* Tagged current trunk.

remains set.

Makefile.am

@@ -1 +1,3 @@
-SUBDIRS = src scripts
+SUBDIRS = externals src scripts corepkgs
+
+EXTRA_DIST = boost/*.hpp boost/format/*.hpp substitute.mk

boost/format.hpp

@@ -0,0 +1,68 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream
+
+// ----------------------------------------------------------------------------
+// format.hpp :  primary header
+// ----------------------------------------------------------------------------
+
+#ifndef BOOST_FORMAT_HPP
+#define BOOST_FORMAT_HPP
+
+#include <vector>
+#include <string>
+#include <sstream>
+#include <cassert>
+
+#include <locale>
+
+#include <boost/format/macros_default.hpp>
+
+namespace boost 
+{
+    template<class E> void throw_exception(E const & e)
+    {
+        throw e;
+    }
+}
+
+#define BOOST_ASSERT(expr) assert(expr)
+
+
+// ****  Forward declarations ----------------------------------
+#include <boost/format/format_fwd.hpp>           // basic_format<Ch,Tr>, and other frontends
+#include <boost/format/internals_fwd.hpp>        // misc forward declarations for internal use
+
+
+// ****  Auxiliary structs (stream_format_state<Ch,Tr> , and format_item<Ch,Tr> )
+#include <boost/format/internals.hpp>    
+
+// ****  Format  class  interface --------------------------------
+#include <boost/format/format_class.hpp>
+
+// **** Exceptions -----------------------------------------------
+#include <boost/format/exceptions.hpp>
+
+// **** Implementation -------------------------------------------
+#include <boost/format/format_implementation.hpp>   // member functions
+
+#include <boost/format/group.hpp>                   // class for grouping arguments
+
+#include <boost/format/feed_args.hpp>               // argument-feeding functions
+#include <boost/format/parsing.hpp>                 // format-string parsing (member-)functions
+
+// **** Implementation of the free functions ----------------------
+#include <boost/format/free_funcs.hpp>
+
+
+#endif // BOOST_FORMAT_HPP

boost/format/exceptions.hpp

@@ -0,0 +1,96 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// exceptions.hpp 
+// ------------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_EXCEPTIONS_HPP
+#define BOOST_FORMAT_EXCEPTIONS_HPP
+
+
+#include <stdexcept>
+
+
+namespace boost {
+
+namespace io {
+
+// **** exceptions -----------------------------------------------
+
+class format_error : public std::exception
+{
+public:
+  format_error() {}
+  virtual const char *what() const throw()
+  {
+    return "boost::format_error: "
+      "format generic failure";
+  }
+};
+
+class bad_format_string : public format_error
+{
+public:
+  bad_format_string() {}
+  virtual const char *what() const throw()
+  {
+    return "boost::bad_format_string: "
+      "format-string is ill-formed";
+  }
+};
+
+class too_few_args : public format_error
+{
+public:
+  too_few_args() {}
+  virtual const char *what() const throw()
+  {
+    return "boost::too_few_args: "
+      "format-string refered to more arguments than were passed";
+  }
+};
+
+class too_many_args : public format_error
+{
+public:
+  too_many_args() {}
+  virtual const char *what() const throw()
+  {
+    return "boost::too_many_args: "
+      "format-string refered to less arguments than were passed";
+  }
+};
+
+
+class  out_of_range : public format_error
+{
+public:
+  out_of_range() {}
+  virtual const char *what() const throw()
+  {
+    return "boost::out_of_range: "
+      "tried to refer to an argument (or item) number which is out of range, "
+      "according to the format string.";
+  }
+};
+
+
+} // namespace io
+
+} // namespace boost
+
+
+#endif // BOOST_FORMAT_EXCEPTIONS_HPP

boost/format/feed_args.hpp

@@ -0,0 +1,248 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream
+
+// ----------------------------------------------------------------------------
+// feed_args.hpp :  functions for processing each argument 
+//                      (feed, feed_manip, and distribute)
+// ----------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_FEED_ARGS_HPP
+#define BOOST_FORMAT_FEED_ARGS_HPP
+
+#include "boost/format/format_class.hpp"
+#include "boost/format/group.hpp"
+
+//#include "boost/throw_exception.hpp"
+
+namespace boost {
+namespace io {
+namespace detail {
+namespace  { 
+
+  template<class Tr, class Ch> inline
+  void empty_buf(BOOST_IO_STD basic_ostringstream<Ch,Tr> & os) { 
+    static const std::basic_string<Ch, Tr> emptyStr;
+    os.str(emptyStr); 
+  }
+
+  template<class Ch, class Tr>
+  void do_pad( std::basic_string<Ch,Tr> & s, 
+                std::streamsize w, 
+                const Ch c, 
+                std::ios_base::fmtflags f, 
+                bool center) 
+    // applies centered / left / right  padding  to the string s.
+    // Effects : string s is padded.
+  {
+    std::streamsize n=w-s.size();
+    if(n<=0) {
+      return;
+    }
+    if(center) 
+      {
+        s.reserve(w); // allocate once for the 2 inserts
+        const std::streamsize n1 = n /2, n0 = n - n1; 
+        s.insert(s.begin(), n0, c);
+        s.append(n1, c);
+      } 
+    else 
+      {
+        if(f & std::ios_base::left) {
+          s.append(n, c);
+        }
+        else {
+          s.insert(s.begin(), n, c);
+        }
+      }
+  } // -do_pad(..) 
+
+
+  template< class Ch, class Tr, class T> inline
+  void put_head(BOOST_IO_STD basic_ostream<Ch, Tr>& , const T& ) {
+  }
+
+  template< class Ch, class Tr, class T> inline
+  void put_head( BOOST_IO_STD basic_ostream<Ch, Tr>& os, const group1<T>& x ) {
+    os << group_head(x.a1_); // send the first N-1 items, not the last
+  }
+
+  template< class Ch, class Tr, class T> inline
+  void put_last( BOOST_IO_STD basic_ostream<Ch, Tr>& os, const T& x ) {
+    os << x ;
+  }
+
+  template< class Ch, class Tr, class T> inline
+  void put_last( BOOST_IO_STD basic_ostream<Ch, Tr>& os, const group1<T>& x ) {
+    os << group_last(x.a1_); // this selects the last element
+  }
+
+#ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST 
+  template< class Ch, class Tr, class T> inline
+  void put_head( BOOST_IO_STD basic_ostream<Ch, Tr>& , T& ) {
+  }
+
+  template< class Ch, class Tr, class T> inline
+  void put_last( BOOST_IO_STD basic_ostream<Ch, Tr>& os, T& x ) {
+    os << x ;
+  }
+#endif
+
+
+
+  
+template< class Ch, class Tr, class T> 
+void put( T x, 
+          const format_item<Ch, Tr>& specs, 
+          std::basic_string<Ch, Tr> & res, 
+          BOOST_IO_STD basic_ostringstream<Ch, Tr>& oss_ )
+{
+  // does the actual conversion of x, with given params, into a string
+  // using the *supplied* strinstream. (the stream state is important)
+
+  typedef std::basic_string<Ch, Tr> string_t;
+  typedef format_item<Ch, Tr>  format_item_t;
+
+  stream_format_state<Ch, Tr>   prev_state(oss_);
+    
+  specs.state_.apply_on(oss_);
+
+  // in case x is a group, apply the manip part of it, 
+  // in order to find width
+  put_head( oss_, x );
+  empty_buf( oss_);
+
+  const std::streamsize w=oss_.width();
+  const std::ios_base::fmtflags fl=oss_.flags();
+  const bool internal = (fl & std::ios_base::internal) != 0;
+  const bool two_stepped_padding = internal
+    &&  ! ( specs.pad_scheme_ & format_item_t::spacepad ) 
+    && specs.truncate_ < 0 ;
+      
+
+  if(! two_stepped_padding) 
+    {
+      if(w>0) // handle simple padding via do_pad, not natively in stream 
+        oss_.width(0);
+      put_last( oss_, x);
+      res = oss_.str();
+
+      if (specs.truncate_ >= 0)
+        res.erase(specs.truncate_);
+
+      // complex pads :
+      if(specs.pad_scheme_ & format_item_t::spacepad)
+        {
+          if( res.size()==0 ||   ( res[0]!='+' && res[0]!='-'  ))
+            {
+              res.insert(res.begin(), 1, ' '); // insert 1 space at  pos 0
+            }
+        }
+      if(w > 0) // need do_pad
+        {
+          do_pad(res,w,oss_.fill(), fl, (specs.pad_scheme_ & format_item_t::centered) !=0 );
+        }
+    } 
+  else  // 2-stepped padding
+    {
+      put_last( oss_, x); // oss_.width() may result in padding.
+      res = oss_.str();
+      
+      if (specs.truncate_ >= 0)
+        res.erase(specs.truncate_);
+
+      if( res.size() - w > 0)
+        { //   length w exceeded
+          // either it was multi-output with first output padding up all width..
+          // either it was one big arg and we are fine.
+          empty_buf( oss_);
+          oss_.width(0);
+          put_last(oss_, x );
+          string_t tmp = oss_.str();  // minimal-length output
+          std::streamsize d;
+          if( (d=w - tmp.size()) <=0 ) 
+            {
+              // minimal length is already >= w, so no padding  (cool!)
+              res.swap(tmp);
+            }
+          else
+            { // hum..  we need to pad (it was necessarily multi-output)
+              typedef typename string_t::size_type size_type;
+              size_type i = 0;
+              while( i<tmp.size() && tmp[i] == res[i] ) // find where we should pad.
+                ++i;
+              tmp.insert(i, static_cast<size_type>( d ), oss_.fill());
+              res.swap( tmp );
+            }
+        }
+      else 
+        { // okay, only one thing was printed and padded, so res is fine.
+        }
+    }
+
+  prev_state.apply_on(oss_);
+  empty_buf( oss_);
+  oss_.clear();
+} // end- put(..)
+
+
+}  // local namespace
+
+
+
+
+
+template< class Ch, class Tr, class T> 
+void distribute(basic_format<Ch,Tr>& self, T x) 
+  // call put(x, ..) on every occurence of the current argument :
+{
+  if(self.cur_arg_ >= self.num_args_)
+    {
+      if( self.exceptions() & too_many_args_bit )
+        boost::throw_exception(too_many_args()); // too many variables have been supplied !
+      else return;
+    }
+  for(unsigned long i=0; i < self.items_.size(); ++i)
+    {
+      if(self.items_[i].argN_ == self.cur_arg_)
+        {
+          put<Ch, Tr, T> (x, self.items_[i], self.items_[i].res_, self.oss_ );
+        }
+    }
+}
+
+template<class Ch, class Tr, class T> 
+basic_format<Ch, Tr>&  feed(basic_format<Ch,Tr>& self, T x) 
+{
+  if(self.dumped_) self.clear();
+  distribute<Ch, Tr, T> (self, x);
+  ++self.cur_arg_;
+  if(self.bound_.size() != 0)
+    {
+      while( self.cur_arg_ < self.num_args_ && self.bound_[self.cur_arg_] )
+        ++self.cur_arg_;
+    }
+
+  // this arg is finished, reset the stream's format state
+  self.state0_.apply_on(self.oss_);
+  return self;
+}
+    
+
+} // namespace detail
+} // namespace io
+} // namespace boost
+
+
+#endif //  BOOST_FORMAT_FEED_ARGS_HPP

boost/format/format_class.hpp

@@ -0,0 +1,140 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// format_class.hpp :  class interface
+// ------------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_CLASS_HPP
+#define BOOST_FORMAT_CLASS_HPP
+
+#include <vector>
+#include <string>
+
+#include <boost/format/format_fwd.hpp>
+#include <boost/format/internals_fwd.hpp>
+
+#include <boost/format/internals.hpp>
+
+namespace boost {
+
+template<class Ch, class Tr>
+class basic_format 
+{
+public:
+  typedef Ch  CharT;   // those 2 are necessary for borland compatibilty,
+  typedef Tr  Traits;  // in the body of the operator% template.
+
+
+  typedef std::basic_string<Ch, Tr>                string_t;
+  typedef BOOST_IO_STD basic_ostringstream<Ch, Tr> internal_stream_t;
+private:
+  typedef BOOST_IO_STD basic_ostream<Ch, Tr>       stream_t;
+  typedef io::detail::stream_format_state<Ch, Tr>  stream_format_state;
+  typedef io::detail::format_item<Ch, Tr>          format_item_t;
+
+public:
+  basic_format(const Ch* str);
+  basic_format(const string_t& s);
+#ifndef BOOST_NO_STD_LOCALE
+  basic_format(const Ch* str, const std::locale & loc);
+  basic_format(const string_t& s, const std::locale & loc);
+#endif // no locale
+  basic_format(const basic_format& x);
+  basic_format& operator= (const basic_format& x);
+
+  basic_format& clear(); // empty the string buffers (except bound arguments, see clear_binds() )
+
+  // pass arguments through those operators :
+  template<class T>  basic_format&   operator%(const T& x) 
+  { 
+    return io::detail::feed<CharT, Traits, const T&>(*this,x);
+  }
+
+#ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST
+  template<class T>  basic_format&   operator%(T& x) 
+  {
+    return io::detail::feed<CharT, Traits, T&>(*this,x);
+  }
+#endif
+
+
+  // system for binding arguments :
+  template<class T>  
+  basic_format&         bind_arg(int argN, const T& val) 
+  {
+    return io::detail::bind_arg_body(*this, argN, val); 
+  }
+  basic_format&         clear_bind(int argN);
+  basic_format&         clear_binds();
+
+  // modify the params of a directive, by applying a manipulator :
+  template<class T> 
+  basic_format&  modify_item(int itemN, const T& manipulator) 
+  {
+    return io::detail::modify_item_body(*this, itemN, manipulator) ;
+  }
+
+  // Choosing which errors will throw exceptions :
+  unsigned char exceptions() const;
+  unsigned char exceptions(unsigned char newexcept);
+
+  // final output
+  string_t str() const;
+  friend BOOST_IO_STD basic_ostream<Ch, Tr>& 
+  operator<< <Ch, Tr> ( BOOST_IO_STD basic_ostream<Ch, Tr>& , const basic_format& ); 
+                      
+
+  template<class Ch2, class Tr2, class T>  friend basic_format<Ch2, Tr2>&  
+  io::detail::feed(basic_format<Ch2,Tr2>&, T);
+    
+  template<class Ch2, class Tr2, class T>  friend   
+  void io::detail::distribute(basic_format<Ch2,Tr2>&, T);
+  
+  template<class Ch2, class Tr2, class T>  friend
+  basic_format<Ch2, Tr2>&  io::detail::modify_item_body(basic_format<Ch2, Tr2>&, int, const T&);
+
+  template<class Ch2, class Tr2, class T> friend
+  basic_format<Ch2, Tr2>&  io::detail::bind_arg_body(basic_format<Ch2, Tr2>&, int, const T&);
+
+// make the members private only if the friend templates are supported
+private:
+
+  // flag bits, used for style_
+  enum style_values  { ordered = 1,        // set only if all directives are  positional directives
+                       special_needs = 4 };     
+
+  // parse the format string :
+  void parse(const string_t&);
+
+  int                           style_;         // style of format-string :  positional or not, etc
+  int                           cur_arg_;       // keep track of wich argument will come
+  int                           num_args_;      // number of expected arguments
+  mutable bool                  dumped_;        // true only after call to str() or <<
+  std::vector<format_item_t>    items_;         // vector of directives (aka items)
+  string_t                      prefix_;        // piece of string to insert before first item
+
+  std::vector<bool>             bound_;         // stores which arguments were bound
+                                                //   size = num_args OR zero
+  internal_stream_t             oss_;           // the internal stream.
+  stream_format_state           state0_;        // reference state for oss_
+  unsigned char                 exceptions_;
+}; // class basic_format
+
+
+} // namespace boost
+
+
+#endif // BOOST_FORMAT_CLASS_HPP

boost/format/format_fwd.hpp

@@ -0,0 +1,55 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// format_fwd.hpp :  forward declarations, for primary header format.hpp
+// ------------------------------------------------------------------------------
+
+#ifndef BOOST_FORMAT_FWD_HPP
+#define BOOST_FORMAT_FWD_HPP
+
+#include <string>
+#include <iosfwd>
+
+namespace boost {
+
+template<class charT, class Traits = BOOST_IO_STD char_traits<charT> > class basic_format;
+
+typedef basic_format<char >     format;
+
+#if !defined(BOOST_NO_STD_WSTRING) && !defined(BOOST_NO_STD_WSTREAMBUF)
+typedef basic_format<wchar_t >  wformat;
+#endif
+
+namespace io {
+enum format_error_bits { bad_format_string_bit = 1, 
+                         too_few_args_bit = 2, too_many_args_bit = 4,
+                         out_of_range_bit = 8,
+                         all_error_bits = 255, no_error_bits=0 };
+                  
+// Convertion:  format   to   string
+template<class Ch, class Tr> 
+std::basic_string<Ch, Tr>     str(const basic_format<Ch, Tr>& ) ;
+
+} // namespace io
+
+
+template< class Ch, class Tr> 
+BOOST_IO_STD basic_ostream<Ch, Tr>& 
+operator<<( BOOST_IO_STD basic_ostream<Ch, Tr>&, const basic_format<Ch, Tr>&);
+
+
+} // namespace boost
+
+#endif // BOOST_FORMAT_FWD_HPP

boost/format/format_implementation.hpp

@@ -0,0 +1,268 @@
+// -*- C++ -*-
+//  Boost general library format ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream
+
+// ----------------------------------------------------------------------------
+// format_implementation.hpp  Implementation of the basic_format class
+// ----------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_IMPLEMENTATION_HPP
+#define BOOST_FORMAT_IMPLEMENTATION_HPP
+
+//#include <boost/throw_exception.hpp>
+//#include <boost/assert.hpp>
+#include <boost/format/format_class.hpp>
+
+namespace boost {
+
+// --------  format:: -------------------------------------------
+template< class Ch, class Tr>
+basic_format<Ch, Tr> ::basic_format(const Ch* str)
+    : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
+      items_(), oss_(), exceptions_(io::all_error_bits)
+{
+    state0_.set_by_stream(oss_);
+    string_t emptyStr;
+    if( !str) str = emptyStr.c_str();
+    parse( str );
+}
+
+#ifndef BOOST_NO_STD_LOCALE
+template< class Ch, class Tr>
+basic_format<Ch, Tr> ::basic_format(const Ch* str, const std::locale & loc)
+    : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
+      items_(), oss_(), exceptions_(io::all_error_bits)
+{
+    oss_.imbue( loc );
+    state0_.set_by_stream(oss_);
+    string_t emptyStr;
+    if( !str) str = emptyStr.c_str();
+    parse( str );
+}
+
+template< class Ch, class Tr>
+basic_format<Ch, Tr> ::basic_format(const string_t& s, const std::locale & loc)
+    : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
+      items_(),  oss_(), exceptions_(io::all_error_bits)
+{
+    oss_.imbue( loc );
+    state0_.set_by_stream(oss_);
+    parse(s);  
+}
+#endif //BOOST_NO_STD_LOCALE
+
+template< class Ch, class Tr>
+basic_format<Ch, Tr> ::basic_format(const string_t& s)
+    : style_(0), cur_arg_(0), num_args_(0), dumped_(false),
+      items_(),  oss_(), exceptions_(io::all_error_bits)
+{
+    state0_.set_by_stream(oss_);
+    parse(s);  
+}
+
+template< class Ch, class Tr>
+basic_format<Ch, Tr> :: basic_format(const basic_format& x)
+    : style_(x.style_), cur_arg_(x.cur_arg_), num_args_(x.num_args_), dumped_(false), 
+      items_(x.items_), prefix_(x.prefix_), bound_(x.bound_), 
+      oss_(),   // <- we obviously can't copy x.oss_
+      state0_(x.state0_), exceptions_(x.exceptions_)
+{ 
+    state0_.apply_on(oss_);
+} 
+
+template< class Ch, class Tr>
+basic_format<Ch, Tr>& basic_format<Ch, Tr> ::operator= (const basic_format& x)
+{
+    if(this == &x)
+      return *this;
+    state0_ = x.state0_;
+    state0_.apply_on(oss_);
+
+    // plus all the other (trivial) assignments :
+    exceptions_ = x.exceptions_;
+    items_ = x.items_;
+    prefix_ = x.prefix_;
+    bound_=x.bound_;
+    style_=x.style_; 
+    cur_arg_=x.cur_arg_; 
+    num_args_=x.num_args_;
+    dumped_=x.dumped_;
+    return *this;
+}
+
+
+template< class Ch, class Tr>
+unsigned char basic_format<Ch,Tr> ::exceptions() const 
+{
+  return exceptions_; 
+}
+
+template< class Ch, class Tr>
+unsigned char basic_format<Ch,Tr> ::exceptions(unsigned char newexcept) 
+{ 
+  unsigned char swp = exceptions_; 
+  exceptions_ = newexcept; 
+  return swp; 
+}
+
+
+template< class Ch, class Tr>
+basic_format<Ch,Tr>& basic_format<Ch,Tr> ::clear()
+  // empty the string buffers (except bound arguments, see clear_binds() )
+  // and make the format object ready for formatting a new set of arguments
+{
+    BOOST_ASSERT( bound_.size()==0 || num_args_ == static_cast<int>(bound_.size()) );
+
+    for(unsigned long i=0; i<items_.size(); ++i){
+      items_[i].state_ = items_[i].ref_state_;
+      // clear converted strings only if the corresponding argument is not  bound :
+      if( bound_.size()==0 || !bound_[ items_[i].argN_ ] )  items_[i].res_.resize(0);
+    }
+    cur_arg_=0; dumped_=false;
+    // maybe first arg is bound:
+    if(bound_.size() != 0)
+      {
+        while(cur_arg_ < num_args_ && bound_[cur_arg_] )      ++cur_arg_;
+      }
+    return *this;
+}
+
+template< class Ch, class Tr>
+basic_format<Ch,Tr>& basic_format<Ch,Tr> ::clear_binds() 
+  // cancel all bindings, and clear()
+{
+    bound_.resize(0);
+    clear();
+    return *this;
+}
+
+template< class Ch, class Tr>
+basic_format<Ch,Tr>& basic_format<Ch,Tr> ::clear_bind(int argN) 
+  // cancel the binding of ONE argument, and clear()
+{
+    if(argN<1 || argN > num_args_ || bound_.size()==0 || !bound_[argN-1] ) 
+      {
+        if( exceptions() & io::out_of_range_bit )
+          boost::throw_exception(io::out_of_range()); // arg not in range.
+        else return *this;
+      }
+    bound_[argN-1]=false;
+    clear();
+    return *this;
+}
+
+
+
+template< class Ch, class Tr>
+std::basic_string<Ch,Tr> basic_format<Ch,Tr> ::str() const
+{
+  dumped_=true;
+  if(items_.size()==0)
+    return prefix_;
+  if( cur_arg_ < num_args_)
+      if( exceptions() & io::too_few_args_bit )
+        boost::throw_exception(io::too_few_args()); // not enough variables have been supplied !
+
+  unsigned long sz = prefix_.size();
+  unsigned long i;
+  for(i=0; i < items_.size(); ++i) 
+    sz += items_[i].res_.size() + items_[i].appendix_.size();
+  string_t res;
+  res.reserve(sz);
+
+  res += prefix_;
+  for(i=0; i < items_.size(); ++i) 
+  {
+    const format_item_t& item = items_[i];
+    res += item.res_;
+    if( item.argN_ == format_item_t::argN_tabulation) 
+    { 
+      BOOST_ASSERT( item.pad_scheme_ & format_item_t::tabulation);
+      std::streamsize  n = item.state_.width_ - res.size();
+      if( n > 0 )
+        res.append( n, item.state_.fill_ );
+    }
+    res += item.appendix_;
+  }
+  return res;
+}
+
+namespace io {
+namespace detail {
+
+template<class Ch, class Tr, class T> 
+basic_format<Ch, Tr>&  bind_arg_body( basic_format<Ch, Tr>& self, 
+                                      int argN, 
+                                      const T& val)
+  // bind one argument to a fixed value
+  // this is persistent over clear() calls, thus also over str() and <<
+{
+    if(self.dumped_) self.clear(); // needed, because we will modify cur_arg_..
+    if(argN<1 || argN > self.num_args_) 
+      {
+        if( self.exceptions() & io::out_of_range_bit )
+          boost::throw_exception(io::out_of_range()); // arg not in range.
+        else return self;
+      }
+    if(self.bound_.size()==0) 
+      self.bound_.assign(self.num_args_,false);
+    else 
+      BOOST_ASSERT( self.num_args_ == static_cast<signed int>(self.bound_.size()) );
+    int o_cur_arg = self.cur_arg_;
+    self.cur_arg_ = argN-1; // arrays begin at 0
+
+    self.bound_[self.cur_arg_]=false; // if already set, we unset and re-sets..
+    self.operator%(val); // put val at the right place, because cur_arg is set
+    
+
+    // Now re-position cur_arg before leaving :
+    self.cur_arg_ = o_cur_arg; 
+    self.bound_[argN-1]=true;
+    if(self.cur_arg_ == argN-1 )
+      // hum, now this arg is bound, so move to next free arg
+      {
+        while(self.cur_arg_ < self.num_args_ && self.bound_[self.cur_arg_])   ++self.cur_arg_;
+      }
+    // In any case, we either have all args, or are on a non-binded arg :
+    BOOST_ASSERT( self.cur_arg_ >= self.num_args_ || ! self.bound_[self.cur_arg_]);
+    return self;
+}
+
+template<class Ch, class Tr, class T> 
+basic_format<Ch, Tr>&  modify_item_body( basic_format<Ch, Tr>& self,
+                                      int itemN, 
+                                      const T& manipulator)
+  // applies a manipulator to the format_item describing a given directive.
+  // this is a permanent change, clear or clear_binds won't cancel that.
+{
+  if(itemN<1 || itemN >= static_cast<signed int>(self.items_.size() )) 
+    {
+      if( self.exceptions() & io::out_of_range_bit ) 
+        boost::throw_exception(io::out_of_range()); // item not in range.
+      else return self;
+    }
+  self.items_[itemN-1].ref_state_.apply_manip( manipulator );
+  self.items_[itemN-1].state_ = self.items_[itemN-1].ref_state_;
+  return self;
+}
+
+} // namespace detail
+
+} // namespace io
+
+} // namespace boost
+
+
+
+#endif  // BOOST_FORMAT_IMPLEMENTATION_HPP

boost/format/free_funcs.hpp

@@ -0,0 +1,72 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// free_funcs.hpp :  implementation of the free functions declared in namespace format
+// ------------------------------------------------------------------------------
+
+#ifndef BOOST_FORMAT_FUNCS_HPP
+#define BOOST_FORMAT_FUNCS_HPP
+
+#include "boost/format/format_class.hpp"
+//#include "boost/throw_exception.hpp"
+
+namespace boost {
+
+namespace io {
+  template<class Ch, class Tr> inline 
+  std::basic_string<Ch, Tr> str(const basic_format<Ch, Tr>& f) 
+    // adds up all pieces of strings and converted items, and return the formatted string
+  {
+    return f.str();
+  }
+}   // - namespace io
+
+template< class Ch, class Tr>
+BOOST_IO_STD basic_ostream<Ch, Tr>& 
+operator<<( BOOST_IO_STD basic_ostream<Ch, Tr>& os, 
+            const boost::basic_format<Ch, Tr>& f) 
+  // effect: "return os << str(f);" but we can try to do it faster
+{
+  typedef boost::basic_format<Ch, Tr>   format_t;
+  if(f.items_.size()==0) 
+    os << f.prefix_;
+  else {
+    if(f.cur_arg_ < f.num_args_)
+      if( f.exceptions() & io::too_few_args_bit )
+        boost::throw_exception(io::too_few_args()); // not enough variables have been supplied !
+    if(f.style_ & format_t::special_needs) 
+        os << f.str();
+    else {
+    // else we dont have to count chars output, so we dump directly to os :
+      os << f.prefix_;
+      for(unsigned long i=0; i<f.items_.size(); ++i) 
+        {
+          const typename format_t::format_item_t& item = f.items_[i];
+          os << item.res_;
+          os << item.appendix_;
+
+        }
+    }
+  }
+  f.dumped_=true;
+  return os;
+}
+
+
+
+} // namespace boost
+
+
+#endif // BOOST_FORMAT_FUNCS_HPP

boost/format/group.hpp

@@ -0,0 +1,680 @@
+
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream
+
+// ----------------------------------------------------------------------------
+
+// group.hpp :  encapsulates a group of manipulators along with an argument
+//                      
+// group_head : cut the last element of a group out.
+// (is overloaded below on each type of group)
+
+// group_last : returns the last element of a group
+// (is overloaded below on each type of group)
+
+// ----------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_GROUP_HPP
+#define BOOST_FORMAT_GROUP_HPP
+
+
+namespace boost {
+namespace io {
+
+
+namespace detail {
+
+
+// empty group, but useful even though.
+struct group0 
+{
+    group0()      {}
+};
+
+template <class Ch, class Tr>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << ( BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group0& )
+{ 
+   return os; 
+}
+
+template <class T1>
+struct group1
+{
+    T1 a1_;
+    group1(T1 a1)
+      : a1_(a1)
+      {}
+};
+
+template <class Ch, class Tr, class T1>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group1<T1>& x)
+{ 
+   os << x.a1_;  
+   return os; 
+}
+
+
+
+
+template <class T1,class T2>
+struct group2
+{
+    T1 a1_;
+    T2 a2_;
+    group2(T1 a1,T2 a2)
+      : a1_(a1),a2_(a2)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group2<T1,T2>& x)
+{ 
+   os << x.a1_<< x.a2_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3>
+struct group3
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    group3(T1 a1,T2 a2,T3 a3)
+      : a1_(a1),a2_(a2),a3_(a3)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group3<T1,T2,T3>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4>
+struct group4
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    group4(T1 a1,T2 a2,T3 a3,T4 a4)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group4<T1,T2,T3,T4>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4,class T5>
+struct group5
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    T5 a5_;
+    group5(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4),a5_(a5)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4,class T5>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group5<T1,T2,T3,T4,T5>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_<< x.a5_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6>
+struct group6
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    T5 a5_;
+    T6 a6_;
+    group6(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4),a5_(a5),a6_(a6)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4,class T5,class T6>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group6<T1,T2,T3,T4,T5,T6>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_<< x.a5_<< x.a6_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7>
+struct group7
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    T5 a5_;
+    T6 a6_;
+    T7 a7_;
+    group7(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4),a5_(a5),a6_(a6),a7_(a7)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4,class T5,class T6,class T7>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group7<T1,T2,T3,T4,T5,T6,T7>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_<< x.a5_<< x.a6_<< x.a7_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8>
+struct group8
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    T5 a5_;
+    T6 a6_;
+    T7 a7_;
+    T8 a8_;
+    group8(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4),a5_(a5),a6_(a6),a7_(a7),a8_(a8)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group8<T1,T2,T3,T4,T5,T6,T7,T8>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_<< x.a5_<< x.a6_<< x.a7_<< x.a8_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9>
+struct group9
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    T5 a5_;
+    T6 a6_;
+    T7 a7_;
+    T8 a8_;
+    T9 a9_;
+    group9(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8,T9 a9)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4),a5_(a5),a6_(a6),a7_(a7),a8_(a8),a9_(a9)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group9<T1,T2,T3,T4,T5,T6,T7,T8,T9>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_<< x.a5_<< x.a6_<< x.a7_<< x.a8_<< x.a9_;  
+   return os; 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9,class T10>
+struct group10
+{
+    T1 a1_;
+    T2 a2_;
+    T3 a3_;
+    T4 a4_;
+    T5 a5_;
+    T6 a6_;
+    T7 a7_;
+    T8 a8_;
+    T9 a9_;
+    T10 a10_;
+    group10(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8,T9 a9,T10 a10)
+      : a1_(a1),a2_(a2),a3_(a3),a4_(a4),a5_(a5),a6_(a6),a7_(a7),a8_(a8),a9_(a9),a10_(a10)
+      {}
+};
+
+template <class Ch, class Tr, class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9,class T10>
+inline
+BOOST_IO_STD basic_ostream<Ch, Tr>&
+operator << (BOOST_IO_STD basic_ostream<Ch, Tr>& os,
+             const group10<T1,T2,T3,T4,T5,T6,T7,T8,T9,T10>& x)
+{ 
+   os << x.a1_<< x.a2_<< x.a3_<< x.a4_<< x.a5_<< x.a6_<< x.a7_<< x.a8_<< x.a9_<< x.a10_;  
+   return os; 
+}
+
+
+
+
+template <class T1,class T2>
+inline
+group1<T1> 
+group_head( group2<T1,T2> const& x)
+{
+   return group1<T1> (x.a1_); 
+}
+
+template <class T1,class T2>
+inline
+group1<T2> 
+group_last( group2<T1,T2> const& x)
+{
+   return group1<T2> (x.a2_); 
+}
+
+
+
+template <class T1,class T2,class T3>
+inline
+group2<T1,T2> 
+group_head( group3<T1,T2,T3> const& x)
+{
+   return group2<T1,T2> (x.a1_,x.a2_); 
+}
+
+template <class T1,class T2,class T3>
+inline
+group1<T3> 
+group_last( group3<T1,T2,T3> const& x)
+{
+   return group1<T3> (x.a3_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4>
+inline
+group3<T1,T2,T3> 
+group_head( group4<T1,T2,T3,T4> const& x)
+{
+   return group3<T1,T2,T3> (x.a1_,x.a2_,x.a3_); 
+}
+
+template <class T1,class T2,class T3,class T4>
+inline
+group1<T4> 
+group_last( group4<T1,T2,T3,T4> const& x)
+{
+   return group1<T4> (x.a4_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4,class T5>
+inline
+group4<T1,T2,T3,T4> 
+group_head( group5<T1,T2,T3,T4,T5> const& x)
+{
+   return group4<T1,T2,T3,T4> (x.a1_,x.a2_,x.a3_,x.a4_); 
+}
+
+template <class T1,class T2,class T3,class T4,class T5>
+inline
+group1<T5> 
+group_last( group5<T1,T2,T3,T4,T5> const& x)
+{
+   return group1<T5> (x.a5_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4,class T5,class T6>
+inline
+group5<T1,T2,T3,T4,T5> 
+group_head( group6<T1,T2,T3,T4,T5,T6> const& x)
+{
+   return group5<T1,T2,T3,T4,T5> (x.a1_,x.a2_,x.a3_,x.a4_,x.a5_); 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6>
+inline
+group1<T6> 
+group_last( group6<T1,T2,T3,T4,T5,T6> const& x)
+{
+   return group1<T6> (x.a6_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7>
+inline
+group6<T1,T2,T3,T4,T5,T6> 
+group_head( group7<T1,T2,T3,T4,T5,T6,T7> const& x)
+{
+   return group6<T1,T2,T3,T4,T5,T6> (x.a1_,x.a2_,x.a3_,x.a4_,x.a5_,x.a6_); 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7>
+inline
+group1<T7> 
+group_last( group7<T1,T2,T3,T4,T5,T6,T7> const& x)
+{
+   return group1<T7> (x.a7_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8>
+inline
+group7<T1,T2,T3,T4,T5,T6,T7> 
+group_head( group8<T1,T2,T3,T4,T5,T6,T7,T8> const& x)
+{
+   return group7<T1,T2,T3,T4,T5,T6,T7> (x.a1_,x.a2_,x.a3_,x.a4_,x.a5_,x.a6_,x.a7_); 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8>
+inline
+group1<T8> 
+group_last( group8<T1,T2,T3,T4,T5,T6,T7,T8> const& x)
+{
+   return group1<T8> (x.a8_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9>
+inline
+group8<T1,T2,T3,T4,T5,T6,T7,T8> 
+group_head( group9<T1,T2,T3,T4,T5,T6,T7,T8,T9> const& x)
+{
+   return group8<T1,T2,T3,T4,T5,T6,T7,T8> (x.a1_,x.a2_,x.a3_,x.a4_,x.a5_,x.a6_,x.a7_,x.a8_); 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9>
+inline
+group1<T9> 
+group_last( group9<T1,T2,T3,T4,T5,T6,T7,T8,T9> const& x)
+{
+   return group1<T9> (x.a9_); 
+}
+
+
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9,class T10>
+inline
+group9<T1,T2,T3,T4,T5,T6,T7,T8,T9> 
+group_head( group10<T1,T2,T3,T4,T5,T6,T7,T8,T9,T10> const& x)
+{
+   return group9<T1,T2,T3,T4,T5,T6,T7,T8,T9> (x.a1_,x.a2_,x.a3_,x.a4_,x.a5_,x.a6_,x.a7_,x.a8_,x.a9_); 
+}
+
+template <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9,class T10>
+inline
+group1<T10> 
+group_last( group10<T1,T2,T3,T4,T5,T6,T7,T8,T9,T10> const& x)
+{
+   return group1<T10> (x.a10_); 
+}
+
+
+
+
+
+} // namespace detail
+
+
+
+// helper functions
+
+
+inline detail::group1< detail::group0 >  
+group() { return detail::group1< detail::group0 > ( detail::group0() ); }
+
+template  <class T1, class Var> 
+inline
+detail::group1< detail::group2<T1, Var const&> >
+  group(T1 a1, Var const& var)
+{ 
+   return detail::group1< detail::group2<T1, Var const&> >
+                   ( detail::group2<T1, Var const&> 
+                        (a1, var) 
+                  );
+}
+
+template  <class T1,class T2, class Var> 
+inline
+detail::group1< detail::group3<T1,T2, Var const&> >
+  group(T1 a1,T2 a2, Var const& var)
+{ 
+   return detail::group1< detail::group3<T1,T2, Var const&> >
+                   ( detail::group3<T1,T2, Var const&> 
+                        (a1,a2, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3, class Var> 
+inline
+detail::group1< detail::group4<T1,T2,T3, Var const&> >
+  group(T1 a1,T2 a2,T3 a3, Var const& var)
+{ 
+   return detail::group1< detail::group4<T1,T2,T3, Var const&> >
+                   ( detail::group4<T1,T2,T3, Var const&> 
+                        (a1,a2,a3, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4, class Var> 
+inline
+detail::group1< detail::group5<T1,T2,T3,T4, Var const&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4, Var const& var)
+{ 
+   return detail::group1< detail::group5<T1,T2,T3,T4, Var const&> >
+                   ( detail::group5<T1,T2,T3,T4, Var const&> 
+                        (a1,a2,a3,a4, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5, class Var> 
+inline
+detail::group1< detail::group6<T1,T2,T3,T4,T5, Var const&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5, Var const& var)
+{ 
+   return detail::group1< detail::group6<T1,T2,T3,T4,T5, Var const&> >
+                   ( detail::group6<T1,T2,T3,T4,T5, Var const&> 
+                        (a1,a2,a3,a4,a5, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6, class Var> 
+inline
+detail::group1< detail::group7<T1,T2,T3,T4,T5,T6, Var const&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6, Var const& var)
+{ 
+   return detail::group1< detail::group7<T1,T2,T3,T4,T5,T6, Var const&> >
+                   ( detail::group7<T1,T2,T3,T4,T5,T6, Var const&> 
+                        (a1,a2,a3,a4,a5,a6, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6,class T7, class Var> 
+inline
+detail::group1< detail::group8<T1,T2,T3,T4,T5,T6,T7, Var const&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7, Var const& var)
+{ 
+   return detail::group1< detail::group8<T1,T2,T3,T4,T5,T6,T7, Var const&> >
+                   ( detail::group8<T1,T2,T3,T4,T5,T6,T7, Var const&> 
+                        (a1,a2,a3,a4,a5,a6,a7, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8, class Var> 
+inline
+detail::group1< detail::group9<T1,T2,T3,T4,T5,T6,T7,T8, Var const&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8, Var const& var)
+{ 
+   return detail::group1< detail::group9<T1,T2,T3,T4,T5,T6,T7,T8, Var const&> >
+                   ( detail::group9<T1,T2,T3,T4,T5,T6,T7,T8, Var const&> 
+                        (a1,a2,a3,a4,a5,a6,a7,a8, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9, class Var> 
+inline
+detail::group1< detail::group10<T1,T2,T3,T4,T5,T6,T7,T8,T9, Var const&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8,T9 a9, Var const& var)
+{ 
+   return detail::group1< detail::group10<T1,T2,T3,T4,T5,T6,T7,T8,T9, Var const&> >
+                   ( detail::group10<T1,T2,T3,T4,T5,T6,T7,T8,T9, Var const&> 
+                        (a1,a2,a3,a4,a5,a6,a7,a8,a9, var) 
+                  );
+}
+
+
+#ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST
+
+template  <class T1, class Var> 
+inline
+detail::group1< detail::group2<T1, Var&> >
+  group(T1 a1, Var& var)
+{ 
+   return detail::group1< detail::group2<T1, Var&> >
+                   ( detail::group2<T1, Var&> 
+                        (a1, var) 
+                  );
+}
+
+template  <class T1,class T2, class Var> 
+inline
+detail::group1< detail::group3<T1,T2, Var&> >
+  group(T1 a1,T2 a2, Var& var)
+{ 
+   return detail::group1< detail::group3<T1,T2, Var&> >
+                   ( detail::group3<T1,T2, Var&> 
+                        (a1,a2, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3, class Var> 
+inline
+detail::group1< detail::group4<T1,T2,T3, Var&> >
+  group(T1 a1,T2 a2,T3 a3, Var& var)
+{ 
+   return detail::group1< detail::group4<T1,T2,T3, Var&> >
+                   ( detail::group4<T1,T2,T3, Var&> 
+                        (a1,a2,a3, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4, class Var> 
+inline
+detail::group1< detail::group5<T1,T2,T3,T4, Var&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4, Var& var)
+{ 
+   return detail::group1< detail::group5<T1,T2,T3,T4, Var&> >
+                   ( detail::group5<T1,T2,T3,T4, Var&> 
+                        (a1,a2,a3,a4, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5, class Var> 
+inline
+detail::group1< detail::group6<T1,T2,T3,T4,T5, Var&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5, Var& var)
+{ 
+   return detail::group1< detail::group6<T1,T2,T3,T4,T5, Var&> >
+                   ( detail::group6<T1,T2,T3,T4,T5, Var&> 
+                        (a1,a2,a3,a4,a5, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6, class Var> 
+inline
+detail::group1< detail::group7<T1,T2,T3,T4,T5,T6, Var&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6, Var& var)
+{ 
+   return detail::group1< detail::group7<T1,T2,T3,T4,T5,T6, Var&> >
+                   ( detail::group7<T1,T2,T3,T4,T5,T6, Var&> 
+                        (a1,a2,a3,a4,a5,a6, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6,class T7, class Var> 
+inline
+detail::group1< detail::group8<T1,T2,T3,T4,T5,T6,T7, Var&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7, Var& var)
+{ 
+   return detail::group1< detail::group8<T1,T2,T3,T4,T5,T6,T7, Var&> >
+                   ( detail::group8<T1,T2,T3,T4,T5,T6,T7, Var&> 
+                        (a1,a2,a3,a4,a5,a6,a7, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8, class Var> 
+inline
+detail::group1< detail::group9<T1,T2,T3,T4,T5,T6,T7,T8, Var&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8, Var& var)
+{ 
+   return detail::group1< detail::group9<T1,T2,T3,T4,T5,T6,T7,T8, Var&> >
+                   ( detail::group9<T1,T2,T3,T4,T5,T6,T7,T8, Var&> 
+                        (a1,a2,a3,a4,a5,a6,a7,a8, var) 
+                  );
+}
+
+template  <class T1,class T2,class T3,class T4,class T5,class T6,class T7,class T8,class T9, class Var> 
+inline
+detail::group1< detail::group10<T1,T2,T3,T4,T5,T6,T7,T8,T9, Var&> >
+  group(T1 a1,T2 a2,T3 a3,T4 a4,T5 a5,T6 a6,T7 a7,T8 a8,T9 a9, Var& var)
+{ 
+   return detail::group1< detail::group10<T1,T2,T3,T4,T5,T6,T7,T8,T9, Var&> >
+                   ( detail::group10<T1,T2,T3,T4,T5,T6,T7,T8,T9, Var&> 
+                        (a1,a2,a3,a4,a5,a6,a7,a8,a9, var) 
+                  );
+}
+
+
+#endif  //end- #ifndef BOOST_NO_OVERLOAD_FOR_NON_CONST
+
+
+} // namespace io
+
+} // namespace boost
+
+
+#endif   // BOOST_FORMAT_GROUP_HPP

boost/format/internals.hpp

@@ -0,0 +1,169 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream
+
+// ----------------------------------------------------------------------------
+// internals.hpp :  internal structs. included by format.hpp
+//                              stream_format_state, and format_item
+// ----------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_INTERNALS_HPP
+#define BOOST_FORMAT_INTERNALS_HPP
+
+
+#include <string>
+#include <sstream>
+
+namespace boost {
+namespace io {
+namespace detail {
+
+
+// --------------
+// set of params that define the format state of a stream
+
+template<class Ch, class Tr> 
+struct stream_format_state 
+{
+  typedef BOOST_IO_STD basic_ios<Ch, Tr>   basic_ios;
+
+  std::streamsize width_;
+  std::streamsize precision_;
+  Ch fill_; 
+  std::ios_base::fmtflags flags_;
+
+  stream_format_state()       : width_(-1), precision_(-1), fill_(0), flags_(std::ios_base::dec)  {}
+  stream_format_state(basic_ios& os)                  {set_by_stream(os); }
+
+  void apply_on(basic_ios & os) const;                //- applies format_state to the stream
+  template<class T> void apply_manip(T manipulator)   //- modifies state by applying manipulator.
+       { apply_manip_body<Ch, Tr, T>( *this, manipulator) ; }
+  void reset();                                       //- sets to default state.
+  void set_by_stream(const basic_ios& os);            //- sets to os's state.
+};  
+
+
+
+// --------------
+// format_item : stores all parameters that can be defined by directives in the format-string
+
+template<class Ch, class Tr>  
+struct format_item 
+{     
+  enum pad_values { zeropad = 1, spacepad =2, centered=4, tabulation = 8 };
+
+  enum arg_values { argN_no_posit   = -1, // non-positional directive. argN will be set later.
+                    argN_tabulation = -2, // tabulation directive. (no argument read) 
+                    argN_ignored    = -3  // ignored directive. (no argument read)
+  };
+  typedef BOOST_IO_STD basic_ios<Ch, Tr>              basic_ios;
+  typedef detail::stream_format_state<Ch, Tr>         stream_format_state;
+  typedef std::basic_string<Ch, Tr>           string_t;
+  typedef BOOST_IO_STD basic_ostringstream<Ch, Tr>    internal_stream_t;
+
+
+  int         argN_;           //- argument number (starts at 0,  eg : %1 => argN=0)
+                               //  negative values are used for items that don't process
+                               //  an argument
+  string_t    res_;            //- result of the formatting of this item
+  string_t    appendix_;       //- piece of string between this item and the next
+
+  stream_format_state ref_state_;// set by parsing the format_string, is only affected by modify_item
+  stream_format_state state_;  // always same as ref_state, _unless_ modified by manipulators 'group(..)'
+
+  // non-stream format-state parameters
+  signed int truncate_;        //- is >=0 for directives like %.5s (take 5 chars from the string)
+  unsigned int pad_scheme_;    //- several possible padding schemes can mix. see pad_values
+
+  format_item() : argN_(argN_no_posit), truncate_(-1), pad_scheme_(0)  {}
+
+  void compute_states();      // sets states  according to truncate and pad_scheme.
+}; 
+
+
+
+// -----------------------------------------------------------
+// Definitions
+// -----------------------------------------------------------
+
+// --- stream_format_state:: -------------------------------------------
+template<class Ch, class Tr> inline
+void stream_format_state<Ch,Tr> ::apply_on(basic_ios & os) const
+  // set the state of this stream according to our params
+{
+      if(width_ != -1)
+        os.width(width_);
+      if(precision_ != -1)
+        os.precision(precision_);
+      if(fill_ != 0)
+        os.fill(fill_);
+      os.flags(flags_);
+}
+
+template<class Ch, class Tr>      inline
+void stream_format_state<Ch,Tr> ::set_by_stream(const basic_ios& os) 
+  // set our params according to the state of this stream
+{
+      flags_ = os.flags();
+      width_ = os.width();
+      precision_ = os.precision();
+      fill_ = os.fill();
+}
+
+template<class Ch, class Tr, class T>  inline
+void apply_manip_body( stream_format_state<Ch, Tr>& self,
+                       T manipulator) 
+  // modify our params according to the manipulator
+{
+      BOOST_IO_STD basic_stringstream<Ch, Tr>  ss;
+      self.apply_on( ss );
+      ss << manipulator;
+      self.set_by_stream( ss );
+}
+
+template<class Ch, class Tr> inline
+void stream_format_state<Ch,Tr> ::reset() 
+  // set our params to standard's default state
+{
+      width_=-1; precision_=-1; fill_=0; 
+      flags_ = std::ios_base::dec; 
+}
+
+
+// --- format_items:: -------------------------------------------
+template<class Ch, class Tr> inline
+void format_item<Ch, Tr> ::compute_states() 
+  // reflect pad_scheme_   on  state_ and ref_state_ 
+  //   because some pad_schemes has complex consequences on several state params.
+{
+  if(pad_scheme_ & zeropad) 
+  {
+    if(ref_state_.flags_ & std::ios_base::left) 
+    {
+      pad_scheme_ = pad_scheme_ & (~zeropad); // ignore zeropad in left alignment
+    }
+    else 
+    { 
+      ref_state_.fill_='0'; 
+      ref_state_.flags_ |= std::ios_base::internal;
+    }
+  }
+  state_ = ref_state_;
+}
+
+
+} } } // namespaces boost :: io :: detail
+
+
+#endif // BOOST_FORMAT_INTERNALS_HPP

boost/format/internals_fwd.hpp

@@ -0,0 +1,65 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// internals_fwd.hpp :  forward declarations, for internal headers
+// ------------------------------------------------------------------------------
+
+#ifndef BOOST_FORMAT_INTERNAL_FWD_HPP
+#define BOOST_FORMAT_INTERNAL_FWD_HPP
+
+#include "boost/format/format_fwd.hpp"
+
+
+namespace boost {
+namespace io {
+
+namespace detail {
+  template<class Ch, class Tr> struct stream_format_state;
+  template<class Ch, class Tr> struct format_item;
+}
+
+
+namespace detail {
+
+  // these functions were intended as methods, 
+  // but MSVC have problems with template member functions :
+
+  // defined in format_implementation.hpp :
+     template<class Ch, class Tr, class T> 
+     basic_format<Ch, Tr>&  modify_item_body( basic_format<Ch, Tr>& self, 
+                                          int itemN, const T& manipulator);
+
+     template<class Ch, class Tr, class T> 
+     basic_format<Ch, Tr>&  bind_arg_body( basic_format<Ch, Tr>& self,
+                                           int argN, const T& val);
+
+    template<class Ch, class Tr, class T> 
+    void apply_manip_body( stream_format_state<Ch, Tr>& self,
+                           T manipulator);
+
+  // argument feeding (defined in feed_args.hpp ) :
+     template<class Ch, class Tr, class T> 
+     void distribute(basic_format<Ch,Tr>& self, T x);
+
+     template<class Ch, class Tr, class T> 
+     basic_format<Ch, Tr>& feed(basic_format<Ch,Tr>& self, T x);
+ 
+} // namespace detail
+
+} // namespace io
+} // namespace boost
+
+
+#endif //  BOOST_FORMAT_INTERNAL_FWD_HPP

boost/format/macros_default.hpp

@@ -0,0 +1,48 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rüdiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// macros_default.hpp : configuration for the format library
+//                       provides default values for the stl workaround macros
+// ------------------------------------------------------------------------------
+
+#ifndef BOOST_FORMAT_MACROS_DEFAULT_HPP
+#define BOOST_FORMAT_MACROS_DEFAULT_HPP
+
+// *** This should go to "boost/config/suffix.hpp".
+
+#ifndef BOOST_IO_STD
+#  define BOOST_IO_STD std::
+#endif
+
+// **** Workaround for io streams, stlport and msvc.
+#ifdef BOOST_IO_NEEDS_USING_DECLARATION
+namespace boost {
+  using std::char_traits;
+  using std::basic_ostream;
+  using std::basic_ostringstream;
+  namespace io {
+    using std::basic_ostream;
+    namespace detail {
+      using std::basic_ios;
+      using std::basic_ostream;
+      using std::basic_ostringstream;
+    }
+  }
+}
+#endif
+
+// ------------------------------------------------------------------------------
+
+#endif // BOOST_FORMAT_MACROS_DEFAULT_HPP

boost/format/parsing.hpp

@@ -0,0 +1,457 @@
+// -*- C++ -*-
+//  Boost general library 'format'   ---------------------------
+//  See http://www.boost.org for updates, documentation, and revision history.
+
+//  (C) Samuel Krempp 2001
+//                  krempp@crans.ens-cachan.fr
+//  Permission to copy, use, modify, sell and
+//  distribute this software is granted provided this copyright notice appears
+//  in all copies. This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+
+// ideas taken from Rudiger Loos's format class
+// and Karl Nelson's ofstream (also took its parsing code as basis for printf parsing)
+
+// ------------------------------------------------------------------------------
+// parsing.hpp :  implementation of the parsing member functions
+//                      ( parse, parse_printf_directive)
+// ------------------------------------------------------------------------------
+
+
+#ifndef BOOST_FORMAT_PARSING_HPP
+#define BOOST_FORMAT_PARSING_HPP
+
+
+#include <boost/format/format_class.hpp>
+//#include <boost/throw_exception.hpp>
+//#include <boost/assert.hpp>
+
+
+namespace boost {
+namespace io {
+namespace detail {
+
+  template<class Ch, class Stream> inline
+  bool wrap_isdigit(Ch c, Stream &os) 
+  {
+#ifndef BOOST_NO_LOCALE_ISIDIGIT
+    return std::isdigit(c, os.rdbuf()->getloc() );
+# else
+    using namespace std;
+    return isdigit(c); 
+#endif 
+  } //end- wrap_isdigit(..)
+
+  template<class Res, class Ch, class Tr> inline
+  Res str2int(const std::basic_string<Ch, Tr>& s, 
+              typename std::basic_string<Ch, Tr>::size_type start, 
+              BOOST_IO_STD basic_ios<Ch,Tr> &os,
+              const Res = Res(0)  ) 
+    // Input : char string, with starting index
+    //         a basic_ios& merely to call its widen/narrow member function in the desired locale.
+    // Effects : reads s[start:] and converts digits into an integral n, of type Res
+    // Returns : n
+  {
+    Res n = 0;
+    while(start<s.size() && wrap_isdigit(s[start], os) ) {
+      char cur_ch = os.narrow( s[start], 0);
+      BOOST_ASSERT(cur_ch != 0 ); // since we called isdigit, this should not happen.
+      n *= 10;
+      n += cur_ch - '0'; // 22.2.1.1.2 of the C++ standard
+      ++start;
+    }
+    return n;
+  }
+
+  template<class Ch, class Tr>
+  void skip_asterisk(const std::basic_string<Ch,Tr> & buf, 
+                     typename std::basic_string<Ch,Tr>::size_type * pos_p,
+                     BOOST_IO_STD basic_ios<Ch, Tr> &os)
+    // skip printf's "asterisk-fields" directives in the format-string buf
+    // Input : char string, with starting index *pos_p
+    //         a basic_ios& merely to call its widen/narrow member function in the desired locale.
+    // Effects : advance *pos_p by skipping printf's asterisk fields.
+    // Returns : nothing
+  {
+    using namespace std;
+    BOOST_ASSERT( pos_p != 0);
+    if(*pos_p >= buf.size() ) return;
+    if(buf[ *pos_p]==os.widen('*')) {
+      ++ (*pos_p);
+      while (*pos_p < buf.size() && wrap_isdigit(buf[*pos_p],os)) ++(*pos_p);
+      if(buf[*pos_p]==os.widen('$')) ++(*pos_p);
+    }
+  }
+
+
+  inline void maybe_throw_exception( unsigned char exceptions)
+    // auxiliary func called by parse_printf_directive
+    // for centralising error handling
+    // it either throws if user sets the corresponding flag, or does nothing.
+  {
+    if(exceptions & io::bad_format_string_bit)
+          boost::throw_exception(io::bad_format_string());
+  }
+    
+
+
+  template<class Ch, class Tr>
+  bool parse_printf_directive(const std::basic_string<Ch, Tr> & buf,
+                              typename std::basic_string<Ch, Tr>::size_type * pos_p,
+                              detail::format_item<Ch, Tr> * fpar,
+                              BOOST_IO_STD basic_ios<Ch,Tr> &os,
+                              unsigned char exceptions)
+    // Input   : a 'printf-directive' in the format-string, starting at buf[ *pos_p ]
+    //           a basic_ios& merely to call its widen/narrow member function in the desired locale.
+    //           a bitset'excpetions' telling whether to throw exceptions on errors.
+    // Returns : true if parse somehow succeeded (possibly ignoring errors if exceptions disabled) 
+    //           false if it failed so bad that the directive should be printed verbatim
+    // Effects : - *pos_p is incremented so that buf[*pos_p] is the first char after the directive
+    //           - *fpar is set with the parameters read in the directive
+  {
+    typedef format_item<Ch, Tr>  format_item_t;
+    BOOST_ASSERT( pos_p != 0);
+    typename std::basic_string<Ch, Tr>::size_type       &i1 = *pos_p,      
+                                                        i0; 
+    fpar->argN_ = format_item_t::argN_no_posit;  // if no positional-directive
+
+    bool in_brackets=false;
+    if(buf[i1]==os.widen('|'))
+      {
+        in_brackets=true;
+        if( ++i1 >= buf.size() ) {
+          maybe_throw_exception(exceptions);
+          return false;
+        }
+      }
+
+    // the flag '0' would be picked as a digit for argument order, but here it's a flag :
+    if(buf[i1]==os.widen('0')) 
+      goto parse_flags;
+
+    // handle argument order (%2$d)  or possibly width specification: %2d
+    i0 = i1;  // save position before digits
+    while (i1 < buf.size() && wrap_isdigit(buf[i1], os))
+      ++i1;
+    if (i1!=i0) 
+      {
+        if( i1 >= buf.size() ) {
+          maybe_throw_exception(exceptions);
+          return false;
+        }
+        int n=str2int(buf,i0, os, int(0) );
+        
+        // %N% case : this is already the end of the directive
+        if( buf[i1] == os.widen('%') ) 
+          {
+            fpar->argN_ = n-1;
+            ++i1;
+            if( in_brackets) 
+              maybe_throw_exception(exceptions); 
+              // but don't return.  maybe "%" was used in lieu of '$', so we go on.
+            else return true;
+          }
+
+        if ( buf[i1]==os.widen('$') ) 
+          {
+            fpar->argN_ = n-1;
+            ++i1;
+          } 
+        else  
+          {
+            // non-positionnal directive
+            fpar->ref_state_.width_ = n;
+            fpar->argN_  = format_item_t::argN_no_posit;
+            goto parse_precision;
+          }
+      }
+    
+  parse_flags: 
+    // handle flags
+    while ( i1 <buf.size()) // as long as char is one of + - = # 0 l h   or ' '
+      {  
+        // misc switches
+        switch (os.narrow(buf[i1], 0)) 
+          {
+          case '\'' : break; // no effect yet. (painful to implement)
+          case 'l':
+          case 'h':  // short/long modifier : for printf-comaptibility (no action needed)
+             break;
+          case '-':
+            fpar->ref_state_.flags_ |= std::ios_base::left;
+            break;
+          case '=':
+            fpar->pad_scheme_ |= format_item_t::centered;
+            break;
+          case ' ':
+            fpar->pad_scheme_ |= format_item_t::spacepad;
+            break;
+          case '+':
+            fpar->ref_state_.flags_ |= std::ios_base::showpos;
+            break;
+          case '0':
+            fpar->pad_scheme_ |= format_item_t::zeropad; 
+            // need to know alignment before really setting flags,
+            // so just add 'zeropad' flag for now, it will be processed later.
+            break;
+          case '#':
+            fpar->ref_state_.flags_ |= std::ios_base::showpoint | std::ios_base::showbase;
+            break;
+          default:
+            goto parse_width;
+          }
+        ++i1;
+      } // loop on flag.
+    if( i1>=buf.size()) {
+      maybe_throw_exception(exceptions);
+      return true; 
+    }
+
+  parse_width:
+    // handle width spec
+    skip_asterisk(buf, &i1, os); // skips 'asterisk fields' :  *, or *N$
+    i0 = i1;  // save position before digits
+    while (i1<buf.size() && wrap_isdigit(buf[i1], os))
+      i1++;
+    
+    if (i1!=i0) 
+      { fpar->ref_state_.width_ = str2int( buf,i0, os, std::streamsize(0) ); }
+
+  parse_precision:
+    if( i1>=buf.size()) { 
+      maybe_throw_exception(exceptions);
+      return true;
+    }
+    // handle precision spec
+    if (buf[i1]==os.widen('.'))  
+      {
+        ++i1;
+        skip_asterisk(buf, &i1, os);
+        i0 = i1;  // save position before digits
+        while (i1<buf.size() && wrap_isdigit(buf[i1], os))
+          ++i1;
+
+        if(i1==i0)
+          fpar->ref_state_.precision_ = 0;
+        else 
+          fpar->ref_state_.precision_ = str2int(buf,i0, os, std::streamsize(0) );
+      }
+    
+    // handle  formatting-type flags :
+    while( i1<buf.size() && 
+           ( buf[i1]==os.widen('l') || buf[i1]==os.widen('L') || buf[i1]==os.widen('h')) )
+      ++i1;
+    if( i1>=buf.size()) {
+      maybe_throw_exception(exceptions);
+      return true;
+    }
+    
+    if( in_brackets && buf[i1]==os.widen('|') ) 
+      {
+        ++i1;
+        return true;
+      }
+    switch (os.narrow(buf[i1], 0) )  
+      {
+      case 'X':
+        fpar->ref_state_.flags_ |= std::ios_base::uppercase;
+      case 'p': // pointer => set hex.
+      case 'x':
+        fpar->ref_state_.flags_ &= ~std::ios_base::basefield;
+        fpar->ref_state_.flags_ |= std::ios_base::hex;
+        break;
+      
+      case 'o':
+        fpar->ref_state_.flags_ &= ~std::ios_base::basefield;
+        fpar->ref_state_.flags_ |=  std::ios_base::oct;
+        break;
+
+      case 'E':
+        fpar->ref_state_.flags_ |=  std::ios_base::uppercase;
+      case 'e':
+        fpar->ref_state_.flags_ &= ~std::ios_base::floatfield;
+        fpar->ref_state_.flags_ |=  std::ios_base::scientific;
+
+        fpar->ref_state_.flags_ &= ~std::ios_base::basefield;
+        fpar->ref_state_.flags_ |=  std::ios_base::dec;
+        break;
+      
+      case 'f':
+        fpar->ref_state_.flags_ &= ~std::ios_base::floatfield;
+        fpar->ref_state_.flags_ |=  std::ios_base::fixed;
+      case 'u':
+      case 'd':
+      case 'i':
+        fpar->ref_state_.flags_ &= ~std::ios_base::basefield;
+        fpar->ref_state_.flags_ |=  std::ios_base::dec;
+        break;
+
+      case 'T':
+        ++i1;
+        if( i1 >= buf.size())
+          maybe_throw_exception(exceptions);
+        else
+          fpar->ref_state_.fill_ = buf[i1];
+        fpar->pad_scheme_ |= format_item_t::tabulation;
+        fpar->argN_ = format_item_t::argN_tabulation; 
+        break;
+      case 't': 
+        fpar->ref_state_.fill_ = os.widen(' ');
+        fpar->pad_scheme_ |= format_item_t::tabulation;
+        fpar->argN_ = format_item_t::argN_tabulation; 
+        break;
+
+      case 'G':
+        fpar->ref_state_.flags_ |= std::ios_base::uppercase;
+        break;
+      case 'g': // 'g' conversion is default for floats.
+        fpar->ref_state_.flags_ &= ~std::ios_base::basefield;
+        fpar->ref_state_.flags_ |=  std::ios_base::dec;
+
+        // CLEAR all floatield flags, so stream will CHOOSE
+        fpar->ref_state_.flags_ &= ~std::ios_base::floatfield; 
+        break;
+
+      case 'C':
+      case 'c': 
+        fpar->truncate_ = 1;
+        break;
+      case 'S':
+      case 's': 
+        fpar->truncate_ = fpar->ref_state_.precision_;
+        fpar->ref_state_.precision_ = -1;
+        break;
+      case 'n' :  
+        fpar->argN_ = format_item_t::argN_ignored;
+        break;
+      default: 
+        maybe_throw_exception(exceptions);
+      }
+    ++i1;
+
+    if( in_brackets )
+      {
+        if( i1<buf.size() && buf[i1]==os.widen('|') ) 
+          {
+            ++i1;
+            return true;
+          }
+        else  maybe_throw_exception(exceptions);
+      }
+    return true;
+  }
+
+} // detail namespace
+} // io namespace
+
+
+// -----------------------------------------------
+//  format :: parse(..)
+
+template<class Ch, class Traits>
+void basic_format<Ch, Traits> ::parse(const string_t & buf) 
+  // parse the format-string
+{
+    using namespace std;
+    const Ch arg_mark = oss_.widen('%');
+    bool ordered_args=true; 
+    int max_argN=-1;
+    typename string_t::size_type i1=0;
+    int num_items=0;
+    
+    // A: find upper_bound on num_items and allocates arrays
+    i1=0; 
+    while( (i1=buf.find(arg_mark,i1)) != string::npos ) 
+    {
+      if( i1+1 >= buf.size() ) {
+        if(exceptions() & io::bad_format_string_bit)
+          boost::throw_exception(io::bad_format_string()); // must not end in "bla bla %"
+        else break; // stop there, ignore last '%'
+      }
+      if(buf[i1+1] == buf[i1] ) { i1+=2; continue; } // escaped "%%" / "##"
+      ++i1;
+      
+      // in case of %N% directives, dont count it double (wastes allocations..) :
+      while(i1 < buf.size() && io::detail::wrap_isdigit(buf[i1],oss_)) ++i1;
+      if( i1 < buf.size() && buf[i1] == arg_mark ) ++ i1;
+
+      ++num_items;
+    }
+    items_.assign( num_items, format_item_t() );
+    
+    // B: Now the real parsing of the format string :
+    num_items=0;
+    i1 = 0;
+    typename string_t::size_type i0 = i1;
+    bool special_things=false;
+    int cur_it=0;
+    while( (i1=buf.find(arg_mark,i1)) != string::npos ) 
+    {
+      string_t & piece = (cur_it==0) ? prefix_ : items_[cur_it-1].appendix_;
+
+      if( buf[i1+1] == buf[i1] ) // escaped mark, '%%'
+      {
+        piece += buf.substr(i0, i1-i0) + buf[i1]; 
+        i1+=2; i0=i1;
+        continue; 
+      }
+      BOOST_ASSERT(  static_cast<unsigned int>(cur_it) < items_.size() || cur_it==0);
+
+      if(i1!=i0) piece += buf.substr(i0, i1-i0);
+      ++i1;
+      
+      bool parse_ok;
+      parse_ok = io::detail::parse_printf_directive(buf, &i1, &items_[cur_it], oss_, exceptions());
+      if( ! parse_ok ) continue; // the directive will be printed verbatim
+
+      i0=i1;
+      items_[cur_it].compute_states(); // process complex options, like zeropad, into stream params.
+
+      int argN=items_[cur_it].argN_;
+      if(argN == format_item_t::argN_ignored)
+        continue;
+      if(argN ==format_item_t::argN_no_posit)
+        ordered_args=false;
+      else if(argN == format_item_t::argN_tabulation) special_things=true;
+      else if(argN > max_argN) max_argN = argN;
+      ++num_items;
+      ++cur_it;
+    } // loop on %'s
+    BOOST_ASSERT(cur_it == num_items);
+    
+    // store the final piece of string
+    string_t & piece = (cur_it==0) ? prefix_ : items_[cur_it-1].appendix_;
+    piece += buf.substr(i0);
+    
+    if( !ordered_args) 
+    {
+      if(max_argN >= 0 )  // dont mix positional with non-positionnal directives
+        {
+          if(exceptions() & io::bad_format_string_bit)
+            boost::throw_exception(io::bad_format_string());
+          // else do nothing. => positionnal arguments are processed as non-positionnal
+        }
+      // set things like it would have been with positional directives :
+      int non_ordered_items = 0;
+      for(int i=0; i< num_items; ++i)
+        if(items_[i].argN_ == format_item_t::argN_no_posit) 
+          {
+            items_[i].argN_ = non_ordered_items;
+            ++non_ordered_items;
+          }
+      max_argN = non_ordered_items-1;
+    }
+    
+    // C: set some member data :
+    items_.resize(num_items);
+
+    if(special_things) style_ |= special_needs;
+    num_args_ = max_argN + 1;
+    if(ordered_args) style_ |=  ordered;
+    else style_ &= ~ordered;
+}
+
+} // namespace boost
+
+
+#endif //  BOOST_FORMAT_PARSING_HPP

configure.ac

@@ -1,4 +1,4 @@
-AC_INIT(nix, 0.1)
+AC_INIT(nix, 0.2pre1)
 AC_CONFIG_SRCDIR(src/nix.cc)
 AC_CONFIG_AUX_DIR(config)
 AM_INIT_AUTOMAKE
@@ -9,6 +9,12 @@ AC_CANONICAL_HOST
 
 AC_PROG_CC
 AC_PROG_CXX
+AC_PROG_RANLIB
 
-AC_CONFIG_FILES([Makefile src/Makefile scripts/Makefile])
+AC_CHECK_LIB(pthread, pthread_mutex_init)
+
+AM_CONFIG_HEADER([config.h])
+AC_CONFIG_FILES([Makefile externals/Makefile src/Makefile scripts/Makefile
+			  corepkgs/Makefile corepkgs/fetchurl/Makefile
+			  corepkgs/nar/Makefile])
 AC_OUTPUT

corepkgs/Makefile.am

@@ -0,0 +1 @@
+SUBDIRS = fetchurl nar

corepkgs/fetchurl/Makefile.am

@@ -0,0 +1,10 @@
+all-local: fetchurl.sh
+
+install-exec-local:
+	$(INSTALL) -d $(datadir)/fix/fetchurl
+	$(INSTALL_DATA) fetchurl.fix $(datadir)/fix/fetchurl
+	$(INSTALL_PROGRAM) fetchurl.sh $(datadir)/fix/fetchurl
+
+include ../../substitute.mk
+
+EXTRA_DIST = fetchurl.fix fetchurl.sh

corepkgs/fetchurl/fetchurl.fix

@@ -0,0 +1,10 @@
+Function(["url", "md5"],
+  Package(
+    [ ("build", Relative("fetchurl/fetchurl.sh"))
+    , ("url", Var("url"))
+    , ("md5", Var("md5"))
+    , ("name", BaseName(Var("url")))
+    , ("id", Var("md5"))
+    ]
+  )
+)

corepkgs/fetchurl/fetchurl.sh

@@ -0,0 +1,10 @@
+#! /bin/sh
+
+echo "downloading $url into $out..."
+wget "$url" -O "$out" || exit 1
+
+actual=$(md5sum -b $out | cut -c1-32)
+if ! test "$actual" == "$md5"; then
+    echo "hash is $actual, expected $md5"
+    exit 1
+fi

corepkgs/nar/Makefile.am

@@ -0,0 +1,12 @@
+all-local: nar.sh unnar.sh
+
+install-exec-local:
+	$(INSTALL) -d $(datadir)/fix/nar
+	$(INSTALL_DATA) nar.fix $(datadir)/fix/nar
+	$(INSTALL_PROGRAM) nar.sh $(datadir)/fix/nar
+	$(INSTALL_DATA) unnar.fix $(datadir)/fix/nar
+	$(INSTALL_PROGRAM) unnar.sh $(datadir)/fix/nar
+
+include ../../substitute.mk
+
+EXTRA_DIST = nar.fix nar.sh unnar.fix unnar.sh

corepkgs/nar/nar.fix

@@ -0,0 +1,8 @@
+Function(["path"],
+  Package(
+    [ ("name", "nar")
+    , ("build", Relative("nar/nar.sh"))
+    , ("path", Var("path"))
+    ]
+  )
+)

corepkgs/nar/nar.sh.in

@@ -0,0 +1,10 @@
+#! /bin/sh
+
+echo "packing $path into $out..."
+mkdir $out || exit 1
+tmp=$out/tmp
+@bindir@/nix --dump --path "$path" | bzip2 > $out/tmp || exit 1
+
+md5=$(md5sum -b $tmp | cut -c1-32)
+if test $? != 0; then exit 1; fi
+mv $out/tmp $out/$md5-`basename $path`.nar.bz2 || exit 1

corepkgs/nar/unnar.fix

@@ -0,0 +1,9 @@
+Function(["nar", "name"],
+  Package(
+    [ ("name", Var("name"))
+    , ("build", Relative("nar/unnar.sh"))
+    , ("nar", Var("nar"))
+    , ("id", Var("id"))
+    ]
+  )
+)

corepkgs/nar/unnar.sh.in

@@ -0,0 +1,4 @@
+#! /bin/sh
+
+echo "unpacking $nar to $out..."
+bunzip2 < $nar | @bindir@/nix --restore "$out" || exit 1

externals/Makefile.am

@@ -0,0 +1,52 @@
+# Berkeley DB
+
+DB = db-4.0.14
+DB_URL = http://www.sleepycat.com/update/snapshot/db-4.0.14.tar.gz
+
+$(DB).tar.gz:
+	wget $(DB_URL)
+
+$(DB): $(DB).tar.gz
+	gunzip < $(DB).tar.gz | tar xvf -
+
+have-db:
+	$(MAKE) $(DB)
+	touch have-db
+
+build-db: have-db
+	(pfx=`pwd` && \
+	cd $(DB)/build_unix && \
+	CC=$(CC) CXX=$(CXX) ../dist/configure --prefix=$$pfx/inst \
+	 --enable-cxx --disable-shared && \
+	make && \
+	make install)
+	touch build-db
+
+
+# CWI ATerm
+
+ATERM = aterm-2.0
+ATERM_URL = http://www.cwi.nl/projects/MetaEnv/aterm/aterm-2.0.tar.gz
+
+$(ATERM).tar.gz:
+	wget $(ATERM_URL)
+
+$(ATERM): $(ATERM).tar.gz
+	gunzip < $(ATERM).tar.gz | tar xvf -
+
+have-aterm:
+	$(MAKE) $(ATERM)
+	touch have-aterm
+
+build-aterm: have-aterm
+	(pfx=`pwd` && \
+	cd $(ATERM) && \
+	./configure --prefix=$$pfx/inst && \
+	make && \
+	make install)
+	touch build-aterm
+
+
+all: build-db build-aterm
+
+EXTRA_DIST = $(DB).tar.gz $(ATERM).tar.gz

scripts/Makefile.am

@@ -1,9 +1,18 @@
 bin_SCRIPTS = nix-switch nix-collect-garbage \
- nix-pull-prebuilts nix-push-prebuilts
+ nix-pull nix-push
+
+noinst_SCRIPTS = nix-profile.sh
 
 install-exec-local:
 	$(INSTALL) -d $(sysconfdir)/profile.d
 	$(INSTALL_PROGRAM) nix-profile.sh $(sysconfdir)/profile.d/nix.sh
 	$(INSTALL) -d $(sysconfdir)/nix
-    # !!! don't overwrite local modifications
-	$(INSTALL_PROGRAM) prebuilts.conf $(sysconfdir)/nix/prebuilts.conf
+# !!! don't overwrite local modifications
+	$(INSTALL_DATA) prebuilts.conf $(sysconfdir)/nix/prebuilts.conf
+
+include ../substitute.mk
+
+EXTRA_DIST = nix-switch.in nix-collect-garbage.in \
+ nix-pull.in nix-push.in nix-profile.sh.in \
+ prebuilts.conf
+

scripts/nix-collect-garbage

@@ -1,22 +0,0 @@
-#! /usr/bin/perl -w
-
-my $prefix = $ENV{"NIX"} || "/nix"; # !!! use prefix
-my $linkdir = "$prefix/var/nix/links";
-
-my %alive;
-
-open HASHES, "nix closure \$(cat $linkdir/*.hash) |";
-while (<HASHES>) {
-	chomp;
-	$alive{$_} = 1;
-}
-close HASHES;
-
-open HASHES, "nix listinst |";
-while (<HASHES>) {
-	chomp;
-	if (!$alive{$_}) {
-	    print "$_\n";
-	}
-}
-close HASHES;

scripts/nix-collect-garbage.in

@@ -0,0 +1,39 @@
+#! /usr/bin/perl -w
+
+my $linkdir = "@localstatedir@/nix/links";
+my $storedir = "@prefix@/store";
+
+my %alive;
+
+my $keepsuccessors = 0;
+my $invert = 0;
+
+foreach my $arg (@ARGV) {
+    if ($arg eq "--keep-successors") { $keepsuccessors = 1; }
+    elsif ($arg eq "--invert") { $invert = 1; }
+    else { die "unknown argument `$arg'" };
+}
+
+my $extraarg = "";
+if ($keepsuccessors) { $extraarg = "--include-successors"; };
+open HASHES, "nix --query --requisites $extraarg \$(cat $linkdir/*.id) |" or die "in `nix -qrh'";
+while (<HASHES>) {
+	chomp;
+	$alive{$_} = 1;
+	if ($invert) { print "$_\n"; };
+}
+close HASHES;
+
+exit 0 if ($invert);
+
+opendir(DIR, $storedir) or die "cannot opendir $storedir: $!";
+my @names = readdir(DIR);
+closedir DIR;
+
+foreach my $name (@names) {
+    next if ($name eq "." || $name eq "..");
+    $name = "$storedir/$name";
+    if (!$alive{$name}) {
+        print "$name\n";
+    }
+}

scripts/nix-profile.sh

@@ -1,19 +0,0 @@
-if test -z "$NIX_SET"; then
-
-    export NIX_SET=1
-
-    NIX_LINKS=/nix/var/nix/links/current
-
-    export PATH=$NIX_LINKS/bin:/nix/bin:$PATH
-
-    export LD_LIBRARY_PATH=$NIX_LINKS/lib:$LD_LIBRARY_PATH
-
-    export LIBRARY_PATH=$NIX_LINKS/lib:$LIBRARY_PATH
-
-    export C_INCLUDE_PATH=$NIX_LINKS/include:$C_INCLUDE_PATH
-
-    export PKG_CONFIG_PATH=$NIX_LINKS/lib/pkgconfig:$PKG_CONFIG_PATH
-
-#    export MANPATH=$NIX_LINKS/man:$MANPATH
-
-fi

scripts/nix-profile.sh.in

@@ -0,0 +1,20 @@
+#if test -z "$NIX_SET"; then
+
+#    export NIX_SET=1
+
+    NIX_LINKS=@localstatedir@/nix/links/current
+
+    export PATH=$NIX_LINKS/bin:@prefix@/bin:$PATH
+
+#    export LD_LIBRARY_PATH=$NIX_LINKS/lib:$LD_LIBRARY_PATH
+
+    export LIBRARY_PATH=$NIX_LINKS/lib:$LIBRARY_PATH
+
+    export C_INCLUDE_PATH=$NIX_LINKS/include:$C_INCLUDE_PATH
+    export CPLUS_INCLUDE_PATH=$NIX_LINKS/include:$CPLUS_INCLUDE_PATH
+
+    export PKG_CONFIG_PATH=$NIX_LINKS/lib/pkgconfig:$PKG_CONFIG_PATH
+
+#    export MANPATH=$NIX_LINKS/man:$MANPATH
+
+#fi

scripts/nix-pull-prebuilts

@@ -1,83 +0,0 @@
-#! /usr/bin/perl -w
-
-my $prefix = $ENV{"NIX"} || "/nix"; # !!! use prefix
-my $etcdir = "$prefix/etc/nix";
-my $knowns = "$prefix/var/nix/known-prebuilts";
-my $tmpfile = "$prefix/var/nix/prebuilts.tmp";
-
-my $conffile = "$etcdir/prebuilts.conf";
-
-umask 0022;
-
-sub register {
-    my $fn = shift;
-    my $url = shift;
-    return unless $fn =~ /([^\/]*)-([0-9a-z]{32})-([0-9a-z]{32})\.tar\.bz2/;
-    my $id = $1;
-    my $pkghash = $2;
-    my $prebuilthash = $3;
-
-    print "$pkghash => $prebuilthash ($id)\n";
-
-    system "nix regprebuilt $pkghash $prebuilthash";
-    if ($?) { die "`nix regprebuilt' failed"; }
-
-    if ($url =~ /^\//) {
-	system "nix regfile $url";
-	if ($?) { die "`nix regfile' failed"; }
-    } else {
-	system "nix regurl $prebuilthash $url";
-	if ($?) { die "`nix regurl' failed"; }
-    }
-
-    print KNOWNS "$pkghash\n";
-}
-
-open KNOWNS, ">$knowns";
-
-open CONFFILE, "<$conffile";
-
-while (<CONFFILE>) {
-    chomp;
-    if (/^\s*(\S+)\s*(\#.*)?$/) {
-        my $url = $1;
-
-        print "obtaining prebuilt list from $url...\n";
-
-        if ($url =~ /^\//) {
-
-            # It's a local path.
-
-            foreach my $fn (glob "$url/*") {
-                register($fn, $fn);
-            }
-
-        } else {
-
-            # It's a URL.
-
-            system "wget '$url' -O '$tmpfile' 2> /dev/null"; # !!! escape
-            if ($?) { die "`wget' failed"; }
-
-            open INDEX, "<$tmpfile";
-
-            while (<INDEX>) {
-                # Get all links to prebuilts, that is, file names of the
-                # form foo-HASH-HASH.tar.bz2.
-                next unless (/HREF=\"([^\"]*)\"/);
-                my $fn = $1;
-                next if $fn =~ /\.\./;
-                next if $fn =~ /\//;
-                register($fn, "$url/$fn");
-            }
-
-            close INDEX;
-
-            unlink $tmpfile;
-        }
-    }
-}
-
-close CONFFILE;
-
-close KNOWNS;

scripts/nix-pull.in

@@ -0,0 +1,91 @@
+#! /usr/bin/perl -w
+
+my $tmpfile = "@localstatedir@/nix/pull.tmp";
+my $conffile = "@sysconfdir@/nix/prebuilts.conf";
+
+my @subs;
+my @sucs;
+
+open CONFFILE, "<$conffile";
+
+while (<CONFFILE>) {
+
+    chomp;
+    if (/^\s*(\S+)\s*(\#.*)?$/) {
+        my $url = $1;
+
+        print "obtaining list of Nix archives at $url...\n";
+
+        system "wget '$url' -O '$tmpfile' 2> /dev/null"; # !!! escape
+        if ($?) { die "`wget' failed"; }
+        
+        open INDEX, "<$tmpfile";
+
+        while (<INDEX>) {
+            # Get all links to prebuilts, that is, file names of the
+            # form foo-HASH-HASH.tar.bz2.
+            next unless (/HREF=\"([^\"]*)\"/);
+            my $fn = $1;
+            next if $fn =~ /\.\./;
+            next if $fn =~ /\//;
+            next unless $fn =~ /^([0-9a-z]{32})-([0-9a-z]{32})(.*)\.nar\.bz2$/;
+            my $hash = $1;
+            my $id = $2;
+            my $outname = $3;
+            my $fsid;
+            if ($outname =~ /^-/) {
+                next unless $outname =~ /^-((s-([0-9a-z]{32}))?.*)$/;
+                $outname = $1;
+                $fsid = $3;
+            } else {
+                $outname = "unnamed";
+            }
+
+            print "registering $id -> $url/$fn\n";
+
+            # Construct a Fix expression that fetches and unpacks a
+            # Nix archive from the network.
+            my $fetch =
+              "App(IncludeFix(\"fetchurl/fetchurl.fix\"), " .
+              "[(\"url\", \"$url/$fn\"), (\"md5\", \"$hash\")])";
+            my $fixexpr = 
+                "App(IncludeFix(\"nar/unnar.fix\"), " .
+                "[ (\"nar\", $fetch)" .
+                ", (\"name\", \"$outname\")" .
+                ", (\"id\", \"$id\")" .
+                "])";
+            
+            my $fixfile = "/tmp/nix-pull-tmp.fix";
+            open FIX, ">$fixfile";
+            print FIX $fixexpr;
+            close FIX;
+
+            # Instantiate a Nix expression from the Fix expression.
+            my $nid = `fix $fixfile`;
+            $? and die "instantiating Nix archive expression";
+            chomp $nid;
+            die unless $nid =~ /^([0-9a-z]{32})$/;
+
+            push @subs, $id;
+            push @subs, $nid;
+
+            # Does the name encode a successor relation?
+            if (defined $fsid) {
+                print "NORMAL $fsid -> $id\n";
+                push @sucs, $fsid;
+                push @sucs, $id;
+            }
+        }
+
+        close INDEX;
+
+        unlink $tmpfile;
+    }
+
+}
+
+system "nix --substitute @subs";
+if ($?) { die "`nix --substitute' failed"; }
+
+system "nix --successor @sucs";
+if ($?) { die "`nix --successor' failed"; }

scripts/nix-push-prebuilts

@@ -1,44 +0,0 @@
-#! /usr/bin/perl -w
-
-my $prefix = $ENV{"NIX"} || "/nix"; # !!! use prefix
-my $etcdir = "$prefix/etc/nix";
-my $exportdir = "$prefix/var/nix/prebuilts/exports";
-my $knowns = "$prefix/var/nix/known-prebuilts";
-
-umask 0022;
-
-# For performance, put the known hashes in an associative array.
-my %knowns = ();
-open KNOWNS, "<$knowns";
-while (<KNOWNS>) {
-    next unless /([0-9a-z]{32})/;
-    $knowns{$1} = 1;
-}
-close KNOWNS;
-
-# For each installed package, check whether a prebuilt is known.
-
-open PKGS, "nix listinst|";
-
-while (<PKGS>) {
-    chomp;
-    next unless /([0-9a-z]{32})/;
-    my $pkghash = $1;
-    if (!defined $knowns{$1}) {
-        # No known prebuilt exists for this package; so export it.
-        print "exporting $pkghash...\n";
-        system "nix export '$exportdir' $pkghash";
-        if ($?) { die "`nix export' failed"; }
-    }
-}
-
-close PKGS;
-
-# Push the prebuilts to the server. !!! FIXME
-
-system "rsync -av -e ssh '$exportdir'/ eelco\@losser.st-lab.cs.uu.nl:/home/eelco/public_html/nix-prebuilts/";
-
-# Rerun `nix-pull-prebuilts' to rescan the prebuilt source locations.
-
-print "running nix-pull-prebuilts...";
-system "nix-pull-prebuilts";

scripts/nix-push.in

@@ -0,0 +1,81 @@
+#! /usr/bin/perl -w
+
+my @pushlist;
+
+foreach my $id (@ARGV) {
+
+    die unless $id =~ /^([0-9a-z]{32})$/;
+
+    # Get all paths referenced by the normalisation of the given 
+    # fstate expression.
+    system "nix --install $id";
+    if ($?) { die "`nix --install' failed"; }
+
+    my @paths;
+
+    open PATHS, "nix --query --requisites --include-successors $id 2> /dev/null |" or die "nix -qr";
+    while (<PATHS>) {
+        chomp;
+        die "bad: $_" unless /^\//;
+        push @paths, $_;
+    }
+    close PATHS;
+
+    # Also add all normal forms that are contained in these paths.
+#    open PATHS, "nix --query --generators --path @paths |" or die "nix -qg";
+#    while (<PATHS>) {
+#	chomp;
+#        die "bad: $_" unless /^\//;
+#	push @paths, $_;
+#    }
+#    close PATHS;
+
+    # For each path, create a Fix expression that turns the path into
+    # a Nix archive.
+    foreach my $path (@paths) {
+
+	next unless ($path =~ /\/([0-9a-z]{32})[^\/]*/);
+	my $pathid = $1;
+
+        # Construct a name for the Nix archive.  If the file is an
+        # fstate successor, encode this into the name.
+        my $name = $pathid;
+        if ($path =~ /-s-([0-9a-z]{32}).nix$/) {
+            $name = "$name-s-$1";
+        }
+        $name = $name . ".nar.bz2";
+
+        # Construct a Fix expression that creates a Nix archive.
+        my $fixexpr = 
+          "App(IncludeFix(\"nar/nar.fix\"), " .
+          "[ (\"path\", Slice([\"$pathid\"], [(\"$path\", \"$pathid\", [])]))" .
+          "])";
+	
+        my $fixfile = "/tmp/nix-push-tmp.fix";
+        open FIX, ">$fixfile";
+        print FIX $fixexpr;
+        close FIX;
+
+        # Instantiate a Nix expression from the Fix expression.
+        my $nid = `fix $fixfile`;
+        $? and die "instantiating Nix archive expression";
+        chomp $nid;
+        die unless $nid =~ /^([0-9a-z]{32})$/;
+
+        # Realise the Nix expression.
+	system "nix --install $nid";
+	if ($?) { die "`nix --install' failed"; }
+        my $npath = `nix --query --list $nid 2> /dev/null`;
+        $? and die "`nix --query --list' failed";
+        chomp $npath;
+
+        push @pushlist, "$npath/*";
+
+        print "$path -> $npath\n";
+    }
+}
+
+# Push the prebuilts to the server. !!! FIXME
+if (scalar @pushlist > 0) {
+    system "rsync -av -e ssh @pushlist eelco\@losser.st-lab.cs.uu.nl:/home/eelco/public_html/nix-dist/";
+}

scripts/nix-switch

@@ -1,66 +0,0 @@
-#! /usr/bin/perl -w
-
-use strict;
-
-my $keep = 0;
-
-if (scalar @ARGV > 0 && $ARGV[0] eq "--keep") {
-    shift @ARGV;
-    $keep = 1;
-}
-
-my $hash = $ARGV[0];
-$hash || die "no package hash specified";
-
-my $prefix = $ENV{"NIX"} || "/nix"; # !!! use prefix
-my $linkdir = "$prefix/var/nix/links";
-
-# Build the specified package, and all its dependencies.
-my $pkgdir = `nix getpkg $hash`;
-if ($?) { die "`nix getpkg' failed"; }
-chomp $pkgdir;
-
-my $id = `nix info $hash | cut -c 34-`;
-if ($?) { die "`nix info' failed"; }
-chomp $id;
-
-# Figure out a generation number.
-my $nr = 0;
-while (-e "$linkdir/$id-$nr") { $nr++; }
-my $link = "$linkdir/$id-$nr";
-
-# Create a symlink from $link to $pkgdir.
-symlink($pkgdir, $link) or die "cannot create $link: $!";
-
-# Also store the hash of $pkgdir.  This is useful for garbage
-# collection and the like.
-my $hashfile = "$linkdir/$id-$nr.hash";
-open HASH, "> $hashfile" or die "cannot create $hashfile";
-print HASH "$hash\n";
-close HASH;
-
-my $current = "$linkdir/current";
-
-# Read the current generation so that we can delete it (if --keep
-# wasn't specified).
-my $oldlink = readlink($current);
-
-# Make $link the current generation by pointing $linkdir/current to
-# it.  The rename() system call is supposed to be essentially atomic
-# on Unix.  That is, if we have links `current -> X' and `new_current
-# -> Y', and we rename new_current to current, a process accessing
-# current will see X or Y, but never a file-not-found or other error
-# condition.  This is sufficient to atomically switch the current link
-# tree.
-
-print "switching $current to $link\n";
-
-my $tmplink = "$linkdir/new_current";
-symlink($link, $tmplink) or die "cannot create $tmplink";
-rename($tmplink, $current) or die "cannot rename $tmplink";
-
-if (!$keep && defined $oldlink) {
-    print "deleting old $oldlink\n";
-    unlink($oldlink) == 1 || print "cannot delete $oldlink\n";
-    unlink("$oldlink.hash") == 1 || print "cannot delete $oldlink.hash\n";
-}

scripts/nix-switch.in

@@ -0,0 +1,82 @@
+#! /usr/bin/perl -w
+
+use strict;
+
+my $keep = 0;
+my $sourceroot = 0;
+my $srcid;
+
+foreach my $arg (@ARGV) {
+    if ($arg eq "--keep") { $keep = 1; }
+    elsif ($arg eq "--source-root") { $sourceroot = 1; }
+    elsif ($arg =~ /^([0-9a-z]{32})$/) { $srcid = $arg; }
+    else { die "unknown argument `$arg'" };
+}
+
+my $linkdir = "@localstatedir@/nix/links";
+
+# Build the specified package, and all its dependencies.
+my $nfid = `nix --install $srcid`;
+if ($?) { die "`nix --install' failed"; }
+chomp $nfid;
+die unless $nfid =~ /^([0-9a-z]{32})$/;
+
+my $pkgdir = `nix --query --list $nfid`;
+if ($?) { die "`nix --query --list' failed"; }
+chomp $pkgdir;
+
+# Figure out a generation number.
+opendir(DIR, $linkdir);
+my $nr = 0;
+foreach my $n (sort(readdir(DIR))) {
+    next if (!($n =~ /^\d+$/));
+    $nr = $n + 1 if ($n >= $nr);
+}
+closedir(DIR);
+
+my $link = "$linkdir/$nr";
+
+# Create a symlink from $link to $pkgdir.
+symlink($pkgdir, $link) or die "cannot create $link: $!";
+
+# Store the id of the normal form.  This is useful for garbage
+# collection and the like.
+my $idfile = "$linkdir/$nr.id";
+open ID, "> $idfile" or die "cannot create $idfile";
+print ID "$nfid\n";
+close ID;
+
+# Optionally store the source id.
+if ($sourceroot) {
+    $idfile = "$linkdir/$nr-src.id";
+    open ID, "> $idfile" or die "cannot create $idfile";
+    print ID "$srcid\n";
+    close ID;
+}
+
+my $current = "$linkdir/current";
+
+# Read the current generation so that we can delete it (if --keep
+# wasn't specified).
+my $oldlink = readlink($current);
+
+# Make $link the current generation by pointing $linkdir/current to
+# it.  The rename() system call is supposed to be essentially atomic
+# on Unix.  That is, if we have links `current -> X' and `new_current
+# -> Y', and we rename new_current to current, a process accessing
+# current will see X or Y, but never a file-not-found or other error
+# condition.  This is sufficient to atomically switch the current link
+# tree.
+
+print "switching $current to $link\n";
+
+my $tmplink = "$linkdir/new_current";
+symlink($link, $tmplink) or die "cannot create $tmplink";
+rename($tmplink, $current) or die "cannot rename $tmplink";
+
+if (!$keep && defined $oldlink) {
+    print "deleting old $oldlink\n";
+    unlink($oldlink) == 1 or print "cannot delete $oldlink\n";
+    unlink("$oldlink.id") == 1 or print "cannot delete $oldlink.id\n";
+    unlink("$oldlink-src.id");
+}

scripts/prebuilts.conf

@@ -1,4 +1,2 @@
-# A list of URLs or local paths from where we obtain prebuilts.
-/nix/var/nix/prebuilts/imports
-/nix/var/nix/prebuilts/exports
-http://losser.st-lab.cs.uu.nl/~eelco/nix-prebuilts/
+# A list of URLs from where we obtain Nix archives.
+http://losser.st-lab.cs.uu.nl/~eelco/nix-dist/

src/Makefile.am

@@ -1,24 +1,51 @@
-bin_PROGRAMS = nix fix
-noinst_PROGRAMS = test
+bin_PROGRAMS = nix nix-hash fix
+check_PROGRAMS = test
 
-AM_CXXFLAGS = -DSYSTEM=\"@host@\" -Wall
+AM_CXXFLAGS = -DSYSTEM=\"@host@\" -Wall -I.. -I../externals/inst/include $(CXXFLAGS)
+AM_LDFLAGS = -L../externals/inst/lib -ldb_cxx -lATerm $(LDFLAGS)
 
-nix_SOURCES = nix.cc db.cc util.cc hash.cc md5.c
-nix_LDADD = -ldb_cxx-4 -lATerm
+nix_SOURCES = nix.cc
+nix_LDADD = libshared.a libnix.a -ldb_cxx -lATerm
 
-fix_SOURCES = fix.cc util.cc hash.cc md5.c
-fix_LDADD = -lATerm
+nix_hash_SOURCES = nix-hash.cc
+nix_hash_LDADD = libshared.a libnix.a -ldb_cxx -lATerm
 
-test_SOURCES = test.cc util.cc hash.cc md5.c
+fix_SOURCES = fix.cc
+fix_LDADD = libshared.a libnix.a -ldb_cxx -lATerm
+
+TESTS = test
+
+test_SOURCES = test.cc
+test_LDADD = libshared.a libnix.a -ldb_cxx -lATerm
+
+noinst_LIBRARIES = libnix.a libshared.a
+
+libnix_a_SOURCES = util.cc hash.cc archive.cc md5.c \
+ store.cc fstate.cc normalise.cc exec.cc \
+ globals.cc db.cc references.cc
+
+libshared_a_SOURCES = shared.cc
+
+libshared_a_CXXFLAGS = \
+ -DNIX_STORE_DIR=\"$(prefix)/store\" \
+ -DNIX_DATA_DIR=\"$(datadir)\" \
+ -DNIX_STATE_DIR=\"$(localstatedir)/nix\" \
+ -DNIX_LOG_DIR=\"$(localstatedir)/log/nix\" \
+ $(AM_CXXFLAGS)
+
+nix.o: nix-help.txt.hh
+
+%.hh: %
+	echo -n '"' > $@
+	sed 's|\(.*\)|\1\\n\\|' < $< >> $@
+	echo '"' >> $@
 
 install-data-local:
 	$(INSTALL) -d $(localstatedir)/nix
-	$(INSTALL) -d $(localstatedir)/nix/descriptors
-	$(INSTALL) -d $(localstatedir)/nix/sources
 	$(INSTALL) -d $(localstatedir)/nix/links
-	$(INSTALL) -d $(localstatedir)/nix/prebuilts
-	$(INSTALL) -d $(localstatedir)/nix/prebuilts/imports
-	$(INSTALL) -d $(localstatedir)/nix/prebuilts/exports
+	ln -sf $(localstatedir)/nix/links/current $(prefix)/current
 	$(INSTALL) -d $(localstatedir)/log/nix
-	$(INSTALL) -d $(prefix)/pkg
-	$(bindir)/nix init
+	$(INSTALL) -d $(prefix)/store
+	$(bindir)/nix --init
+
+EXTRA_DIST = *.hh *.h

src/archive.cc

@@ -0,0 +1,338 @@
+#include <vector>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <fcntl.h>
+
+#include "archive.hh"
+#include "util.hh"
+
+
+static string archiveVersion1 = "nix-archive-1";
+
+
+static void writePadding(unsigned int len, DumpSink & sink)
+{
+    if (len % 8) {
+        unsigned char zero[8];
+        memset(zero, 0, sizeof(zero));
+        sink(zero, 8 - (len % 8));
+    }
+}
+
+
+static void writeInt(unsigned int n, DumpSink & sink)
+{
+    unsigned char buf[8];
+    memset(buf, 0, sizeof(buf));
+    buf[0] = n & 0xff;
+    buf[1] = (n >> 8) & 0xff;
+    buf[2] = (n >> 16) & 0xff;
+    buf[3] = (n >> 24) & 0xff;
+    sink(buf, sizeof(buf));
+}
+
+
+static void writeString(const string & s, DumpSink & sink)
+{
+    unsigned int len = s.length();
+    writeInt(len, sink);
+    sink((const unsigned char *) s.c_str(), len);
+    writePadding(len, sink);
+}
+
+
+static void dump(const string & path, DumpSink & sink);
+
+
+static void dumpEntries(const string & path, DumpSink & sink)
+{
+    DIR * dir = opendir(path.c_str());
+    if (!dir) throw SysError("opening directory " + path);
+
+    vector<string> names;
+
+    struct dirent * dirent;
+    while (errno = 0, dirent = readdir(dir)) {
+        string name = dirent->d_name;
+        if (name == "." || name == "..") continue;
+        names.push_back(name);
+    }
+    if (errno) throw SysError("reading directory " + path);
+
+    sort(names.begin(), names.end());
+
+    for (vector<string>::iterator it = names.begin();
+         it != names.end(); it++)
+    {
+        writeString("entry", sink);
+        writeString("(", sink);
+        writeString("name", sink);
+        writeString(*it, sink);
+        writeString("node", sink);
+        dump(path + "/" + *it, sink);
+        writeString(")", sink);
+    }
+    
+    closedir(dir); /* !!! close on exception */
+}
+
+
+static void dumpContents(const string & path, unsigned int size, 
+    DumpSink & sink)
+{
+    writeString("contents", sink);
+    writeInt(size, sink);
+
+    int fd = open(path.c_str(), O_RDONLY);
+    if (fd == -1) throw SysError(format("opening file `%1%'") % path);
+    
+    unsigned char buf[65536];
+
+    unsigned int total = 0;
+    ssize_t n;
+    while ((n = read(fd, buf, sizeof(buf)))) {
+        if (n == -1) throw SysError("reading file " + path);
+        total += n;
+        sink(buf, n);
+    }
+
+    if (total != size)
+        throw SysError("file changed while reading it: " + path);
+
+    writePadding(size, sink);
+
+    close(fd); /* !!! close on exception */
+}
+
+
+static void dump(const string & path, DumpSink & sink)
+{
+    struct stat st;
+    if (lstat(path.c_str(), &st))
+        throw SysError(format("getting attributes of path `%1%'") % path);
+
+    writeString("(", sink);
+
+    if (S_ISREG(st.st_mode)) {
+        writeString("type", sink);
+        writeString("regular", sink);
+        if (st.st_mode & S_IXUSR) {
+            writeString("executable", sink);
+            writeString("", sink);
+        }
+        dumpContents(path, st.st_size, sink);
+    } 
+
+    else if (S_ISDIR(st.st_mode)) {
+        writeString("type", sink);
+        writeString("directory", sink);
+        dumpEntries(path, sink);
+    }
+
+    else if (S_ISLNK(st.st_mode)) {
+        writeString("type", sink);
+        writeString("symlink", sink);
+        char buf[st.st_size];
+        if (readlink(path.c_str(), buf, st.st_size) != st.st_size)
+            throw SysError("reading symbolic link " + path);
+        writeString("target", sink);
+        writeString(string(buf, st.st_size), sink);
+    }
+
+    else throw Error("unknown file type: " + path);
+
+    writeString(")", sink);
+}
+
+
+void dumpPath(const string & path, DumpSink & sink)
+{
+    writeString(archiveVersion1, sink);
+    dump(path, sink);
+}
+
+
+static Error badArchive(string s)
+{
+    return Error("bad archive: " + s);
+}
+
+
+static void readPadding(unsigned int len, RestoreSource & source)
+{
+    if (len % 8) {
+        unsigned char zero[8];
+        unsigned int n = 8 - (len % 8);
+        source(zero, n);
+        for (unsigned int i = 0; i < n; i++)
+            if (zero[i]) throw badArchive("non-zero padding");
+    }
+}
+
+static unsigned int readInt(RestoreSource & source)
+{
+    unsigned char buf[8];
+    source(buf, sizeof(buf));
+    if (buf[4] || buf[5] || buf[6] || buf[7])
+        throw Error("implementation cannot deal with > 32-bit integers");
+    return
+        buf[0] |
+        (buf[1] << 8) |
+        (buf[2] << 16) |
+        (buf[3] << 24);
+}
+
+
+static string readString(RestoreSource & source)
+{
+    unsigned int len = readInt(source);
+    char buf[len];
+    source((unsigned char *) buf, len);
+    readPadding(len, source);
+    return string(buf, len);
+}
+
+
+static void skipGeneric(RestoreSource & source)
+{
+    if (readString(source) == "(") {
+        while (readString(source) != ")")
+            skipGeneric(source);
+    }
+}
+
+
+static void restore(const string & path, RestoreSource & source);
+
+
+static void restoreEntry(const string & path, RestoreSource & source)
+{
+    string s, name;
+
+    s = readString(source);
+    if (s != "(") throw badArchive("expected open tag");
+
+    while (1) {
+        s = readString(source);
+
+        if (s == ")") {
+            break;
+        } else if (s == "name") {
+            name = readString(source);
+        } else if (s == "node") {
+            if (s == "") throw badArchive("entry name missing");
+            restore(path + "/" + name, source);
+        } else {
+            throw badArchive("unknown field " + s);
+            skipGeneric(source);
+        }
+    }
+}
+
+
+static void restoreContents(int fd, const string & path, RestoreSource & source)
+{
+    unsigned int size = readInt(source);
+    unsigned int left = size;
+    unsigned char buf[65536];
+
+    while (left) {
+        unsigned int n = sizeof(buf);
+        if (n > left) n = left;
+        source(buf, n);
+        if (write(fd, buf, n) != (ssize_t) n)
+            throw SysError("writing file " + path);
+        left -= n;
+    }
+
+    readPadding(size, source);
+}
+
+
+static void restore(const string & path, RestoreSource & source)
+{
+    string s;
+
+    s = readString(source);
+    if (s != "(") throw badArchive("expected open tag");
+
+    enum { tpUnknown, tpRegular, tpDirectory, tpSymlink } type = tpUnknown;
+    int fd = -1; /* !!! close on exception */
+
+    while (1) {
+        s = readString(source);
+
+        if (s == ")") {
+            break;
+        }
+
+        else if (s == "type") {
+            if (type != tpUnknown)
+                throw badArchive("multiple type fields");
+            string t = readString(source);
+
+            if (t == "regular") {
+                type = tpRegular;
+                fd = open(path.c_str(), O_CREAT | O_EXCL | O_WRONLY, 0666);
+                if (fd == -1)
+                    throw SysError("creating file " + path);
+            }
+
+            else if (t == "directory") {
+                type = tpDirectory;
+                if (mkdir(path.c_str(), 0777) == -1)
+                    throw SysError("creating directory " + path);
+            }
+
+            else if (t == "symlink") {
+                type = tpSymlink;
+            }
+            
+            else throw badArchive("unknown file type " + t);
+            
+        }
+
+        else if (s == "contents" && type == tpRegular) {
+            restoreContents(fd, path, source);
+        }
+
+        else if (s == "executable" && type == tpRegular) {
+            readString(source);
+            struct stat st;
+            if (fstat(fd, &st) == -1)
+                throw SysError("fstat");
+            if (fchmod(fd, st.st_mode | (S_IXUSR | S_IXGRP | S_IXOTH)) == -1)
+                throw SysError("fchmod");
+        }
+
+        else if (s == "entry" && type == tpDirectory) {
+            restoreEntry(path, source);
+        }
+
+        else if (s == "target" && type == tpSymlink) {
+            string target = readString(source);
+            if (symlink(target.c_str(), path.c_str()) == -1)
+                throw SysError("creating symlink " + path);
+        }
+
+        else {
+            throw badArchive("unknown field " + s);
+            skipGeneric(source);
+        }
+        
+    }
+
+    if (fd != -1) close(fd);
+}
+
+
+void restorePath(const string & path, RestoreSource & source)
+{
+    if (readString(source) != archiveVersion1)
+        throw badArchive("expected Nix archive");
+    restore(path, source);
+}
+

src/archive.hh

@@ -0,0 +1,60 @@
+#include <string>
+
+using namespace std;
+
+
+/* dumpPath creates a Nix archive of the specified path.  The format
+   is as follows:
+
+   IF path points to a REGULAR FILE:
+     dump(path) = attrs(
+       [ ("type", "regular")
+       , ("contents", contents(path))
+       ])
+
+   IF path points to a DIRECTORY:
+     dump(path) = attrs(
+       [ ("type", "directory")
+       , ("entries", concat(map(f, sort(entries(path)))))
+       ])
+       where f(fn) = attrs(
+         [ ("name", fn)
+         , ("file", dump(path + "/" + fn))
+         ])
+
+   where:
+
+     attrs(as) = concat(map(attr, as)) + encN(0) 
+     attrs((a, b)) = encS(a) + encS(b)
+
+     encS(s) = encN(len(s)) + s + (padding until next 64-bit boundary)
+
+     encN(n) = 64-bit little-endian encoding of n.
+
+     contents(path) = the contents of a regular file.
+
+     sort(strings) = lexicographic sort by 8-bit value (strcmp).
+
+     entries(path) = the entries of a directory, without `.' and
+     `..'.
+
+     `+' denotes string concatenation. */
+
+struct DumpSink 
+{
+    virtual void operator () (const unsigned char * data, unsigned int len) = 0;
+};
+
+void dumpPath(const string & path, DumpSink & sink);
+
+
+struct RestoreSource
+{
+    /* The callee should store exactly *len bytes in the buffer
+       pointed to by data.  It should block if that much data is not
+       yet available, or throw an error if it is not going to be
+       available. */
+    virtual void operator () (unsigned char * data, unsigned int len) = 0;
+};
+
+void restorePath(const string & path, RestoreSource & source);

src/db.cc

@@ -65,7 +65,10 @@ bool queryDB(const string & filename, const string & dbname,
         err = db->get(0, &kt, &dt, 0);
         if (err) return false;
 
-        data = string((char *) dt.get_data(), dt.get_size());
+        if (!dt.get_data())
+            data = "";
+        else
+            data = string((char *) dt.get_data(), dt.get_size());
     
     } catch (DbException e) { rethrow(e); }
 
@@ -73,6 +76,40 @@ bool queryDB(const string & filename, const string & dbname,
 }
 
 
+bool queryListDB(const string & filename, const string & dbname,
+    const string & key, Strings & data)
+{
+    string d;
+
+    if (!queryDB(filename, dbname, key, d))
+        return false;
+
+    string::iterator it = d.begin();
+    
+    while (it != d.end()) {
+
+        if (it + 4 > d.end())
+            throw Error(format("short db entry: `%1%'") % d);
+        
+        unsigned int len;
+        len = (unsigned char) *it++;
+        len |= ((unsigned char) *it++) << 8;
+        len |= ((unsigned char) *it++) << 16;
+        len |= ((unsigned char) *it++) << 24;
+        
+        if (it + len > d.end())
+            throw Error(format("short db entry: `%1%'") % d);
+
+        string s;
+        while (len--) s += *it++;
+
+        data.push_back(s);
+    }
+
+    return true;
+}
+
+
 void setDB(const string & filename, const string & dbname,
     const string & key, const string & data)
 {
@@ -85,6 +122,29 @@ void setDB(const string & filename, const string & dbname,
 }
 
 
+void setListDB(const string & filename, const string & dbname,
+    const string & key, const Strings & data)
+{
+    string d;
+    
+    for (Strings::const_iterator it = data.begin();
+         it != data.end(); it++)
+    {
+        string s = *it;
+        unsigned int len = s.size();
+
+        d += len & 0xff;
+        d += (len >> 8) & 0xff;
+        d += (len >> 16) & 0xff;
+        d += (len >> 24) & 0xff;
+        
+        d += s;
+    }
+
+    setDB(filename, dbname, key, d);
+}
+
+
 void delDB(const string & filename, const string & dbname,
     const string & key)
 {
@@ -97,7 +157,7 @@ void delDB(const string & filename, const string & dbname,
 
 
 void enumDB(const string & filename, const string & dbname,
-    DBPairs & contents)
+    Strings & keys)
 {
     try {
 
@@ -108,11 +168,9 @@ void enumDB(const string & filename, const string & dbname,
         DbcClose cursorCloser(cursor);
 
         Dbt kt, dt;
-        while (cursor->get(&kt, &dt, DB_NEXT) != DB_NOTFOUND) {
-            string key((char *) kt.get_data(), kt.get_size());
-            string data((char *) dt.get_data(), dt.get_size());
-            contents.push_back(DBPair(key, data));
-        }
+        while (cursor->get(&kt, &dt, DB_NEXT) != DB_NOTFOUND)
+            keys.push_back(
+                string((char *) kt.get_data(), kt.get_size()));
 
     } catch (DbException e) { rethrow(e); }
 }

src/db.hh

@@ -4,23 +4,28 @@
 #include <string>
 #include <list>
 
-using namespace std;
+#include "util.hh"
 
-typedef pair<string, string> DBPair;
-typedef list<DBPair> DBPairs;
+using namespace std;
 
 void createDB(const string & filename, const string & dbname);
 
 bool queryDB(const string & filename, const string & dbname,
     const string & key, string & data);
 
+bool queryListDB(const string & filename, const string & dbname,
+    const string & key, Strings & data);
+
 void setDB(const string & filename, const string & dbname,
     const string & key, const string & data);
 
+void setListDB(const string & filename, const string & dbname,
+    const string & key, const Strings & data);
+
 void delDB(const string & filename, const string & dbname,
     const string & key);
 
 void enumDB(const string & filename, const string & dbname,
-    DBPairs & contents);
+    Strings & keys);
 
 #endif /* !__DB_H */

src/exec.cc

@@ -0,0 +1,119 @@
+#include <iostream>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <fcntl.h>
+
+#include "exec.hh"
+#include "util.hh"
+#include "globals.hh"
+
+
+class AutoDelete
+{
+    string path;
+    bool del;
+public:
+
+    AutoDelete(const string & p) : path(p) 
+    {
+        del = true;
+    }
+
+    ~AutoDelete()
+    {
+        if (del) deletePath(path);
+    }
+
+    void cancel()
+    {
+        del = false;
+    }
+};
+
+
+/* Run a program. */
+void runProgram(const string & program, Environment env)
+{
+    /* Create a log file. */
+    string logFileName = nixLogDir + "/run.log";
+    /* !!! auto-pclose on exit */
+    FILE * logFile = popen(("tee -a " + logFileName + " >&2").c_str(), "w"); /* !!! escaping */
+    if (!logFile)
+        throw SysError(format("creating log file `%1%'") % logFileName);
+
+    /* Create a temporary directory where the build will take
+       place. */
+    static int counter = 0;
+    string tmpDir = (format("/tmp/nix-%1%-%2%") % getpid() % counter++).str();
+
+    if (mkdir(tmpDir.c_str(), 0777) == -1)
+        throw SysError(format("creating directory `%1%'") % tmpDir);
+
+    AutoDelete delTmpDir(tmpDir);
+
+    /* Fork a child to build the package. */
+    pid_t pid;
+    switch (pid = fork()) {
+            
+    case -1:
+        throw SysError("unable to fork");
+
+    case 0: 
+
+        try { /* child */
+
+            if (chdir(tmpDir.c_str()) == -1)
+                throw SysError(format("changing into to `%1%'") % tmpDir);
+
+            /* Fill in the environment.  We don't bother freeing
+               the strings, since we'll exec or die soon
+               anyway. */
+            const char * env2[env.size() + 1];
+            int i = 0;
+            for (Environment::iterator it = env.begin();
+                 it != env.end(); it++, i++)
+                env2[i] = (new string(it->first + "=" + it->second))->c_str();
+            env2[i] = 0;
+
+            /* Dup the log handle into stderr. */
+            if (dup2(fileno(logFile), STDERR_FILENO) == -1)
+                throw SysError("cannot pipe standard error into log file");
+            
+            /* Dup stderr to stdin. */
+            if (dup2(STDERR_FILENO, STDOUT_FILENO) == -1)
+                throw SysError("cannot dup stderr into stdout");
+
+            /* Execute the program.  This should not return. */
+            execle(program.c_str(), baseNameOf(program).c_str(), 0, env2);
+
+            throw SysError(format("unable to execute %1%") % program);
+            
+        } catch (exception & e) {
+            cerr << format("build error: %1%\n") % e.what();
+        }
+        _exit(1);
+
+    }
+
+    /* parent */
+
+    /* Close the logging pipe.  Note that this should not cause
+       the logger to exit until builder exits (because the latter
+       has an open file handle to the former). */
+    pclose(logFile);
+    
+    /* Wait for the child to finish. */
+    int status;
+    if (waitpid(pid, &status, 0) != pid)
+        throw Error("unable to wait for child");
+    
+    if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
+        delTmpDir.cancel();
+        throw Error("unable to build package");
+    }
+}
+
+

src/exec.hh

@@ -0,0 +1,18 @@
+#ifndef __EXEC_H
+#define __EXEC_H
+
+#include <string>
+#include <map>
+
+using namespace std;
+
+
+/* A Unix environment is a mapping from strings to strings. */
+typedef map<string, string> Environment;
+
+
+/* Run a program. */
+void runProgram(const string & program, Environment env);
+
+
+#endif /* !__EXEC_H */

src/fix.cc

@@ -1,368 +1,343 @@
-#include <iostream>
 #include <map>
+#include <iostream>
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/wait.h>
-
-extern "C" {
-#include <aterm2.h>
-}
-
-#include "util.hh"
-#include "hash.hh"
+#include "globals.hh"
+#include "normalise.hh"
+#include "shared.hh"
 
 
-static string nixDescriptorDir;
+typedef ATerm Expr;
 
+typedef map<ATerm, ATerm> NormalForms;
+typedef map<FSId, Hash> PkgHashes;
 
-static bool verbose = false;
-
-
-/* Mapping of Fix file names to the hashes of the resulting Nix
-   descriptors. */
-typedef map<string, Hash> DescriptorMap;
-
-
-void registerFile(string filename)
+struct EvalState 
 {
-    int res = system(("nix regfile " + filename).c_str()); 
-    /* !!! escape */
-    if (WEXITSTATUS(res) != 0)
-        throw Error("cannot register " + filename + " with Nix");
-}
-
-
-void registerURL(Hash hash, string url)
-{
-    int res = system(("nix regurl " + (string) hash + " " + url).c_str());
-    /* !!! escape */
-    if (WEXITSTATUS(res) != 0)
-        throw Error("cannot register " + 
-            (string) hash + " -> " + url + " with Nix");
-}
-
-
-Error badTerm(const string & msg, ATerm e)
-{
-    char * s = ATwriteToString(e);
-    return Error(msg + ", in `" + s + "'");
-}
-
-
-/* Term evaluation. */
-
-typedef map<string, ATerm> BindingsMap;
-
-struct EvalContext
-{
-    string dir;
-    DescriptorMap * done;
-    BindingsMap * vars;
+    Strings searchDirs;
+    NormalForms normalForms;
+    PkgHashes pkgHashes; /* normalised package hashes */
 };
 
 
-ATerm evaluate(ATerm e, EvalContext ctx);
-Hash instantiateDescriptor(string filename, EvalContext ctx);
+static Expr evalFile(EvalState & state, string fileName);
+static Expr evalExpr(EvalState & state, Expr e);
 
 
-string evaluateStr(ATerm e, EvalContext ctx)
+static string searchPath(const Strings & searchDirs, string relPath)
 {
-    e = evaluate(e, ctx);
-    char * s;
-    if (ATmatch(e, "Str(<str>)", &s))
-        return s;
-    else throw badTerm("string value expected", e);
+    if (string(relPath, 0, 1) == "/") return relPath;
+
+    for (Strings::const_iterator i = searchDirs.begin();
+         i != searchDirs.end(); i++)
+    {
+        string path = *i + "/" + relPath;
+        if (pathExists(path)) return path;
+    }
+
+    throw Error(
+        format("path `%1%' not found in any of the search directories")
+        % relPath);
 }
 
 
-bool evaluateBool(ATerm e, EvalContext ctx)
-{
-    e = evaluate(e, ctx);
-    if (ATmatch(e, "Bool(True)"))
-        return true;
-    else if (ATmatch(e, "Bool(False)"))
-        return false;
-    else throw badTerm("boolean value expected", e);
-}
-
-
-ATerm evaluate(ATerm e, EvalContext ctx)
+static Expr substExpr(string x, Expr rep, Expr e)
 {
     char * s;
-    ATerm e2, e3;
-    ATerm eCond, eTrue, eFalse;
+    Expr e2;
 
-    /* Check for normal forms first. */
-
-    if (ATmatch(e, "Str(<str>)", &s) ||
-        ATmatch(e, "Bool(True)") || ATmatch(e, "Bool(False)"))
-        return e;
-    
-    else if (
-        ATmatch(e, "Pkg(<str>)", &s) || 
-        ATmatch(e, "File(<str>)", &s))
-    {
-        parseHash(s);
-        return e;
-    }
-
-    /* Short-hands. */
-
-    else if (ATmatch(e, "<str>", &s))
-        return ATmake("Str(<str>)", s);
-
-    else if (ATmatch(e, "True", &s))
-        return ATmake("Bool(True)", s);
-
-    else if (ATmatch(e, "False", &s))
-        return ATmake("Bool(False)", s);
-
-    /* Functions. */
-
-    /* `Var' looks up a variable. */
-    else if (ATmatch(e, "Var(<str>)", &s)) {
-        string name(s);
-        ATerm e2 = (*ctx.vars)[name];
-        if (!e2) throw Error("undefined variable " + name);
-        return evaluate(e2, ctx); /* !!! update binding */
-    }
-
-    /* `Fix' recursively instantiates a Fix descriptor, returning the
-       hash of the generated Nix descriptor. */
-    else if (ATmatch(e, "Fix(<term>)", &e2)) {
-        string filename = absPath(evaluateStr(e2, ctx), ctx.dir); /* !!! */
-        return ATmake("Pkg(<str>)",
-            ((string) instantiateDescriptor(filename, ctx)).c_str());
-    }
-
-#if 0
-    /* `Source' copies the specified file to nixSourcesDir, registers
-       it with Nix, and returns the hash of the file. */
-    else if (ATmatch(e, "Source(<term>)", &e2)) {
-        string source = absPath(evaluateStr(e2, ctx), ctx.dir); /* !!! */
-        string target = nixSourcesDir + "/" + baseNameOf(source);
-
-        // Don't copy if filename is already in nixSourcesDir.
-        if (source != target) {
-            if (verbose)
-                cerr << "copying source " << source << endl;
-            string cmd = "cp -p " + source + " " + target;
-            int res = system(cmd.c_str());
-            if (WEXITSTATUS(res) != 0)
-                throw Error("cannot copy " + source + " to " + target);
-        }
-        
-        registerFile(target);
-        return ATmake("File(<str>)", hashFile(target).c_str());
-    }
-#endif
-
-    /* `Local' registers a file with Nix, and returns the file's
-       hash. */
-    else if (ATmatch(e, "Local(<term>)", &e2)) {
-        string filename = absPath(evaluateStr(e2, ctx), ctx.dir); /* !!! */
-        Hash hash = hashFile(filename);
-        registerFile(filename); /* !!! */
-        return ATmake("File(<str>)", ((string) hash).c_str());
-    }
-
-    /* `Url' registers a mapping from a hash to an url with Nix, and
-       returns the hash. */
-    else if (ATmatch(e, "Url(<term>, <term>)", &e2, &e3)) {
-        Hash hash = parseHash(evaluateStr(e2, ctx));
-        string url = evaluateStr(e3, ctx);
-        registerURL(hash, url);
-        return ATmake("File(<str>)", ((string) hash).c_str());
-    }
-
-    /* `If' provides conditional evaluation. */
-    else if (ATmatch(e, "If(<term>, <term>, <term>)", 
-                 &eCond, &eTrue, &eFalse)) 
-        return evaluate(evaluateBool(eCond, ctx) ? eTrue : eFalse, ctx);
-
-    else throw badTerm("invalid expression", e);
-}
-
-
-string getStringFromMap(BindingsMap & bindingsMap,
-    const string & name)
-{
-    ATerm e = bindingsMap[name];
-    if (!e) throw Error("binding " + name + " is not set");
-    char * s;
-    if (ATmatch(e, "Str(<str>)", &s))
-        return s;
-    else
-        throw Error("binding " + name + " is not a string");
-}
-
-
-/* Instantiate a Fix descriptors into a Nix descriptor, recursively
-   instantiating referenced descriptors as well. */
-Hash instantiateDescriptor(string filename, EvalContext ctx)
-{
-    /* Already done? */
-    DescriptorMap::iterator isInMap = ctx.done->find(filename);
-    if (isInMap != ctx.done->end()) return isInMap->second;
-
-    /* No. */
-    ctx.dir = dirOf(filename);
-
-    /* Read the Fix descriptor as an ATerm. */
-    ATerm inTerm = ATreadFromNamedFile(filename.c_str());
-    if (!inTerm) throw Error("cannot read aterm " + filename);
-
-    ATerm bindings;
-    if (!ATmatch(inTerm, "Descr(<term>)", &bindings))
-        throw Error("invalid term in " + filename);
-    
-    /* Iterate over the bindings and evaluate them to normal form. */
-    BindingsMap bindingsMap; /* the normal forms */
-    ctx.vars = &bindingsMap;
-
-    char * cname;
-    ATerm value;
-    while (ATmatch(bindings, "[Bind(<str>, <term>), <list>]", 
-               &cname, &value, &bindings)) 
-    {
-        string name(cname);
-        ATerm e = evaluate(value, ctx);
-        bindingsMap[name] = e;
-    }
-
-    /* Construct a descriptor identifier by concatenating the package
-       and release ids. */
-    string pkgId = getStringFromMap(bindingsMap, "pkgId");
-    string releaseId = getStringFromMap(bindingsMap, "releaseId");
-    string id = pkgId + "-" + releaseId;
-    bindingsMap["id"] = ATmake("Str(<str>)", id.c_str());
-
-    /* Add a system name. */
-    bindingsMap["system"] = ATmake("Str(<str>)", thisSystem.c_str());
-         
-    /* Construct the resulting ATerm.  Note that iterating over the
-       map yields the bindings in sorted order, which is exactly the
-       canonical form for Nix descriptors. */
-    ATermList bindingsList = ATempty;
-    for (BindingsMap::iterator it = bindingsMap.begin();
-         it != bindingsMap.end(); it++)
-        /* !!! O(n^2) */
-        bindingsList = ATappend(bindingsList,
-            ATmake("Bind(<str>, <term>)", it->first.c_str(), it->second));
-    ATerm outTerm = ATmake("Descr(<term>)", bindingsList);
-
-    /* Write out the resulting ATerm. */
-    string tmpFilename = nixDescriptorDir + "/tmp";
-    if (!ATwriteToNamedTextFile(outTerm, tmpFilename.c_str()))
-        throw Error("cannot write aterm to " + tmpFilename);
-
-    Hash outHash = hashFile(tmpFilename);
-    string outFilename = nixDescriptorDir + "/" + 
-        id + "-" + (string) outHash + ".nix";
-    if (rename(tmpFilename.c_str(), outFilename.c_str()))
-        throw Error("cannot rename " + tmpFilename + " to " + outFilename);
-
-    /* Register it with Nix. */
-    registerFile(outFilename);
-
-    if (verbose)
-        cerr << "instantiated " << (string) outHash 
-             << " from " << filename << endl;
-
-    (*ctx.done)[filename] = outHash;
-    return outHash;
-}
-
-
-/* Instantiate a set of Fix descriptors into Nix descriptors. */
-void instantiateDescriptors(Strings filenames)
-{
-    DescriptorMap done;
-
-    EvalContext ctx;
-    ctx.done = &done;
-
-    for (Strings::iterator it = filenames.begin();
-         it != filenames.end(); it++)
-    {
-        string filename = absPath(*it);
-        cout << (string) instantiateDescriptor(filename, ctx) << endl;
-    }
-}
-
-
-/* Print help. */
-void printUsage()
-{
-    cerr <<
-"Usage: fix ...\n\
-";
-}
-
-
-/* Parse the command-line arguments, call the right operation. */
-void run(Strings::iterator argCur, Strings::iterator argEnd)
-{
-    umask(0022);
-
-    Strings extraArgs;
-    enum { cmdUnknown, cmdInstantiate } command = cmdUnknown;
-
-    char * homeDir = getenv(nixHomeDirEnvVar.c_str());
-    if (homeDir) nixHomeDir = homeDir;
-
-    nixDescriptorDir = nixHomeDir + "/var/nix/descriptors";
-
-    for ( ; argCur != argEnd; argCur++) {
-        string arg(*argCur);
-        if (arg == "-h" || arg == "--help") {
-            printUsage();
-            return;
-        } else if (arg == "-v" || arg == "--verbose") {
-            verbose = true;
-        } else if (arg == "--instantiate" || arg == "-i") {
-            command = cmdInstantiate;
-        } else if (arg[0] == '-')
-            throw UsageError("invalid option `" + arg + "'");
+    if (ATmatch(e, "Var(<str>)", &s))
+        if (x == s)
+            return rep;
         else
-            extraArgs.push_back(arg);
+            return e;
+
+    if (ATmatch(e, "Lam(<str>, <term>)", &s, &e2))
+        if (x == s)
+            return e;
+    /* !!! unfair substitutions */
+
+    /* Generically substitute in subterms. */
+
+    if (ATgetType(e) == AT_APPL) {
+        AFun fun = ATgetAFun(e);
+        int arity = ATgetArity(fun);
+        ATermList args = ATempty;
+
+        for (int i = arity - 1; i >= 0; i--)
+            args = ATinsert(args, substExpr(x, rep, ATgetArgument(e, i)));
+        
+        return (ATerm) ATmakeApplList(fun, args);
     }
 
-    switch (command) {
+    if (ATgetType(e) == AT_LIST) {
+        ATermList in = (ATermList) e;
+        ATermList out = ATempty;
 
-        case cmdInstantiate:
-            instantiateDescriptors(extraArgs);
-            break;
+        while (!ATisEmpty(in)) {
+            out = ATinsert(out, substExpr(x, rep, ATgetFirst(in)));
+            in = ATgetNext(in);
+        }
 
-        default:
-            throw UsageError("no operation specified");
+        return (ATerm) ATreverse(out);
     }
+
+    throw badTerm("do not know how to substitute", e);
 }
 
 
-int main(int argc, char * * argv)
+static Expr substExprMany(ATermList formals, ATermList args, Expr body)
 {
-    ATerm bottomOfStack;
-    ATinit(argc, argv, &bottomOfStack);
+    char * s;
+    Expr e;
 
-    /* Put the arguments in a vector. */
-    Strings args;
-    while (argc--) args.push_back(*argv++);
-    Strings::iterator argCur = args.begin(), argEnd = args.end();
+    /* !!! check args against formals */
 
-    argCur++;
+    while (!ATisEmpty(args)) {
+        ATerm tup = ATgetFirst(args);
+        if (!ATmatch(tup, "(<str>, <term>)", &s, &e))
+            throw badTerm("expected an argument tuple", tup);
+
+        body = substExpr(s, e, body);
+
+        args = ATgetNext(args);
+    }
+    
+    return body;
+}
+
+
+Hash hashPackage(EvalState & state, FState fs)
+{
+    if (fs.type == FState::fsDerive) {
+        for (FSIds::iterator i = fs.derive.inputs.begin();
+             i != fs.derive.inputs.end(); i++)
+        {
+            PkgHashes::iterator j = state.pkgHashes.find(*i);
+            if (j == state.pkgHashes.end())
+                throw Error(format("unknown package id %1%") % (string) *i);
+            *i = j->second;
+        }
+    }
+    return hashTerm(unparseFState(fs));
+}
+
+
+static Expr evalExpr2(EvalState & state, Expr e)
+{
+    char * s1;
+    Expr e1, e2, e3, e4;
+    ATermList bnds;
+
+    /* Normal forms. */
+    if (ATmatch(e, "<str>", &s1) ||
+        ATmatch(e, "Function([<list>], <term>)", &e1, &e2) ||
+        ATmatch(e, "FSId(<str>)", &s1))
+        return e;
 
     try {
-        run(argCur, argEnd);
-    } catch (UsageError & e) {
-        cerr << "error: " << e.what() << endl
-             << "Try `fix -h' for more information.\n";
-        return 1;
-    } catch (exception & e) {
-        cerr << "error: " << e.what() << endl;
-        return 1;
+        Hash pkgHash = hashPackage(state, parseFState(e));
+        FSId pkgId = writeTerm(e, "");
+        state.pkgHashes[pkgId] = pkgHash;
+        return ATmake("FSId(<str>)", ((string) pkgId).c_str());
+    } catch (...) { /* !!! catch parse errors only */
     }
 
-    return 0;
+    /* Application. */
+    if (ATmatch(e, "App(<term>, [<list>])", &e1, &e2)) {
+        e1 = evalExpr(state, e1);
+        if (!ATmatch(e1, "Function([<list>], <term>)", &e3, &e4))
+            throw badTerm("expecting a function", e1);
+        return evalExpr(state,
+            substExprMany((ATermList) e3, (ATermList) e2, e4));
+    }
+
+    /* Fix inclusion. */
+    if (ATmatch(e, "IncludeFix(<str>)", &s1)) {
+        string fileName(s1);
+        return evalFile(state, s1);
+    }
+
+    /* Relative files. */
+    if (ATmatch(e, "Relative(<str>)", &s1)) {
+        string srcPath = searchPath(state.searchDirs, s1);
+        string dstPath;
+        FSId id;
+        addToStore(srcPath, dstPath, id, true);
+
+        SliceElem elem;
+        elem.path = dstPath;
+        elem.id = id;
+        FState fs;
+        fs.type = FState::fsSlice;
+        fs.slice.roots.push_back(id);
+        fs.slice.elems.push_back(elem);
+
+        Hash pkgHash = hashPackage(state, fs);
+        FSId pkgId = writeTerm(unparseFState(fs), "");
+        state.pkgHashes[pkgId] = pkgHash;
+
+        msg(lvlChatty, format("copied `%1%' -> %2%")
+            % srcPath % (string) pkgId);
+
+        return ATmake("FSId(<str>)", ((string) pkgId).c_str());
+    }
+
+    /* Packages are transformed into Derive fstate expressions. */
+    if (ATmatch(e, "Package([<list>])", &bnds)) {
+
+        /* Evaluate the bindings and put them in a map. */
+        map<string, ATerm> bndMap;
+        bndMap["platform"] = ATmake("<str>", SYSTEM);
+        while (!ATisEmpty(bnds)) {
+            ATerm bnd = ATgetFirst(bnds);
+            if (!ATmatch(bnd, "(<str>, <term>)", &s1, &e1))
+                throw badTerm("binding expected", bnd);
+            bndMap[s1] = evalExpr(state, e1);
+            bnds = ATgetNext(bnds);
+        }
+
+        /* Gather information for building the Derive expression. */
+        FState fs;
+        fs.type = FState::fsDerive;
+        fs.derive.platform = SYSTEM;
+        string name;
+        FSId outId;
+        bool outIdGiven = false;
+        bnds = ATempty;
+
+        for (map<string, ATerm>::iterator it = bndMap.begin();
+             it != bndMap.end(); it++)
+        {
+            string key = it->first;
+            ATerm value = it->second;
+
+            if (ATmatch(value, "FSId(<str>)", &s1)) {
+                FSId id = parseHash(s1);
+                Strings paths = fstatePaths(id);
+                if (paths.size() != 1) abort();
+                string path = *(paths.begin());
+                fs.derive.inputs.push_back(id);
+                fs.derive.env.push_back(StringPair(key, path));
+                if (key == "build") fs.derive.builder = path;
+            }
+            else if (ATmatch(value, "<str>", &s1)) {
+                if (key == "name") name = s1;
+                if (key == "id") { 
+                    outId = parseHash(s1);
+                    outIdGiven = true;
+                }
+                fs.derive.env.push_back(StringPair(key, s1));
+            }
+            else throw badTerm("invalid package argument", value);
+
+            bnds = ATinsert(bnds, 
+                ATmake("(<str>, <term>)", key.c_str(), value));
+        }
+
+        if (fs.derive.builder == "")
+            throw badTerm("no builder specified", e);
+        
+        if (name == "")
+            throw badTerm("no package name specified", e);
+        
+        /* Hash the fstate-expression with no outputs to produce a
+           unique but deterministic path name for this package. */
+        if (!outIdGiven) outId = hashPackage(state, fs);
+        string outPath = 
+            canonPath(nixStore + "/" + ((string) outId).c_str() + "-" + name);
+        fs.derive.env.push_back(StringPair("out", outPath));
+        fs.derive.outputs.push_back(DeriveOutput(outPath, outId));
+
+        /* Write the resulting term into the Nix store directory. */
+        Hash pkgHash = outIdGiven
+            ? hashString((string) outId + outPath)
+            : hashPackage(state, fs);
+        FSId pkgId = writeTerm(unparseFState(fs), "-d-" + name);
+        state.pkgHashes[pkgId] = pkgHash;
+
+        msg(lvlChatty, format("instantiated `%1%' -> %2%")
+            % name % (string) pkgId);
+
+        return ATmake("FSId(<str>)", ((string) pkgId).c_str());
+    }
+
+    /* BaseName primitive function. */
+    if (ATmatch(e, "BaseName(<term>)", &e1)) {
+        e1 = evalExpr(state, e1);
+        if (!ATmatch(e1, "<str>", &s1)) 
+            throw badTerm("string expected", e1);
+        return ATmake("<str>", baseNameOf(s1).c_str());
+    }
+
+    /* Barf. */
+    throw badTerm("invalid expression", e);
 }
+
+
+static Expr evalExpr(EvalState & state, Expr e)
+{
+    /* Consult the memo table to quickly get the normal form of
+       previously evaluated expressions. */
+    NormalForms::iterator i = state.normalForms.find(e);
+    if (i != state.normalForms.end()) return i->second;
+
+    /* Otherwise, evaluate and memoize. */
+    Expr nf = evalExpr2(state, e);
+    state.normalForms[e] = nf;
+    return nf;
+}
+
+
+static Expr evalFile(EvalState & state, string relPath)
+{
+    string path = searchPath(state.searchDirs, relPath);
+    Nest nest(lvlTalkative, format("evaluating file `%1%'") % path);
+    Expr e = ATreadFromNamedFile(path.c_str());
+    if (!e) 
+        throw Error(format("unable to read a term from `%1%'") % path);
+    return evalExpr(state, e);
+}
+
+
+void run(Strings args)
+{
+    EvalState state;
+    Strings files;
+
+    state.searchDirs.push_back(".");
+    state.searchDirs.push_back(nixDataDir + "/fix");
+    
+    for (Strings::iterator it = args.begin();
+         it != args.end(); )
+    {
+        string arg = *it++;
+
+        if (arg == "--includedir" || arg == "-I") {
+            if (it == args.end())
+                throw UsageError(format("argument required in `%1%'") % arg);
+            state.searchDirs.push_back(*it++);
+        }
+        else if (arg == "--verbose" || arg == "-v")
+            verbosity = (Verbosity) ((int) verbosity + 1);
+        else if (arg[0] == '-')
+            throw UsageError(format("unknown flag `%1%`") % arg);
+        else
+            files.push_back(arg);
+    }
+
+    if (files.empty()) throw UsageError("no files specified");
+
+    for (Strings::iterator it = files.begin();
+         it != files.end(); it++)
+    {
+        Expr e = evalFile(state, *it);
+        char * s;
+        if (ATmatch(e, "FSId(<str>)", &s)) {
+            cout << format("%1%\n") % s;
+        }
+        else throw badTerm("top level is not a package", e);
+    }
+}
+
+
+string programId = "fix";

src/fstate.cc

@@ -0,0 +1,227 @@
+#include "fstate.hh"
+#include "globals.hh"
+#include "store.hh"
+
+
+string printTerm(ATerm t)
+{
+    char * s = ATwriteToString(t);
+    return s;
+}
+
+
+Error badTerm(const format & f, ATerm t)
+{
+    return Error(format("%1%, in `%2%'") % f.str() % printTerm(t));
+}
+
+
+Hash hashTerm(ATerm t)
+{
+    return hashString(printTerm(t));
+}
+
+
+ATerm termFromId(const FSId & id)
+{
+    string path = expandId(id);
+    ATerm t = ATreadFromNamedFile(path.c_str());
+    if (!t) throw Error(format("cannot read aterm from `%1%'") % path);
+    return t;
+}
+
+
+FSId writeTerm(ATerm t, const string & suffix, FSId id)
+{
+    /* By default, the id of a term is its hash. */
+    if (id == FSId()) id = hashTerm(t);
+
+    string path = canonPath(nixStore + "/" + 
+        (string) id + suffix + ".nix");
+    if (!ATwriteToNamedTextFile(t, path.c_str()))
+        throw Error(format("cannot write aterm %1%") % path);
+
+//     debug(format("written term %1% = %2%") % (string) id %
+//         printTerm(t));
+
+    registerPath(path, id);
+    return id;
+}
+
+
+static void parseIds(ATermList ids, FSIds & out)
+{
+    while (!ATisEmpty(ids)) {
+        char * s;
+        ATerm id = ATgetFirst(ids);
+        if (!ATmatch(id, "<str>", &s))
+            throw badTerm("not an id", id);
+        out.push_back(parseHash(s));
+        ids = ATgetNext(ids);
+    }
+}
+
+
+static void checkSlice(const Slice & slice)
+{
+    if (slice.elems.size() == 0)
+        throw Error("empty slice");
+
+    FSIdSet decl;
+    for (SliceElems::const_iterator i = slice.elems.begin();
+         i != slice.elems.end(); i++)
+        decl.insert(i->id);
+    
+    for (FSIds::const_iterator i = slice.roots.begin();
+         i != slice.roots.end(); i++)
+        if (decl.find(*i) == decl.end())
+            throw Error(format("undefined id: %1%") % (string) *i);
+    
+    for (SliceElems::const_iterator i = slice.elems.begin();
+         i != slice.elems.end(); i++)
+        for (FSIds::const_iterator j = i->refs.begin();
+             j != i->refs.end(); j++)
+            if (decl.find(*j) == decl.end())
+                throw Error(format("undefined id: %1%") % (string) *j);
+}
+
+
+/* Parse a slice. */
+static bool parseSlice(ATerm t, Slice & slice)
+{
+    ATermList roots, elems;
+    
+    if (!ATmatch(t, "Slice([<list>], [<list>])", &roots, &elems))
+        return false;
+
+    parseIds(roots, slice.roots);
+
+    while (!ATisEmpty(elems)) {
+        char * s1, * s2;
+        ATermList refs;
+        ATerm t = ATgetFirst(elems);
+        if (!ATmatch(t, "(<str>, <str>, [<list>])", &s1, &s2, &refs))
+            throw badTerm("not a slice element", t);
+        SliceElem elem;
+        elem.path = s1;
+        elem.id = parseHash(s2);
+        parseIds(refs, elem.refs);
+        slice.elems.push_back(elem);
+        elems = ATgetNext(elems);
+    }
+
+    checkSlice(slice);
+    return true;
+}
+
+
+static bool parseDerive(ATerm t, Derive & derive)
+{
+    ATermList outs, ins, bnds;
+    char * builder;
+    char * platform;
+
+    if (!ATmatch(t, "Derive([<list>], [<list>], <str>, <str>, [<list>])",
+            &outs, &ins, &builder, &platform, &bnds))
+        return false;
+
+    while (!ATisEmpty(outs)) {
+        char * s1, * s2;
+        ATerm t = ATgetFirst(outs);
+        if (!ATmatch(t, "(<str>, <str>)", &s1, &s2))
+            throw badTerm("not a derive output", t);
+        derive.outputs.push_back(DeriveOutput(s1, parseHash(s2)));
+        outs = ATgetNext(outs);
+    }
+
+    parseIds(ins, derive.inputs);
+
+    derive.builder = builder;
+    derive.platform = platform;
+    
+    while (!ATisEmpty(bnds)) {
+        char * s1, * s2;
+        ATerm bnd = ATgetFirst(bnds);
+        if (!ATmatch(bnd, "(<str>, <str>)", &s1, &s2))
+            throw badTerm("tuple of strings expected", bnd);
+        derive.env.push_back(StringPair(s1, s2));
+        bnds = ATgetNext(bnds);
+    }
+
+    return true;
+}
+
+
+FState parseFState(ATerm t)
+{
+    FState fs;
+    if (parseSlice(t, fs.slice))
+        fs.type = FState::fsSlice;
+    else if (parseDerive(t, fs.derive))
+        fs.type = FState::fsDerive;
+    else throw badTerm("not an fstate-expression", t);
+    return fs;
+}
+
+
+static ATermList unparseIds(const FSIds & ids)
+{
+    ATermList l = ATempty;
+    for (FSIds::const_iterator i = ids.begin();
+         i != ids.end(); i++)
+        l = ATinsert(l,
+            ATmake("<str>", ((string) *i).c_str()));
+    return ATreverse(l);
+}
+
+
+static ATerm unparseSlice(const Slice & slice)
+{
+    ATermList roots = unparseIds(slice.roots);
+    
+    ATermList elems = ATempty;
+    for (SliceElems::const_iterator i = slice.elems.begin();
+         i != slice.elems.end(); i++)
+        elems = ATinsert(elems,
+            ATmake("(<str>, <str>, <term>)",
+                i->path.c_str(),
+                ((string) i->id).c_str(),
+                unparseIds(i->refs)));
+
+    return ATmake("Slice(<term>, <term>)", roots, elems);
+}
+
+
+static ATerm unparseDerive(const Derive & derive)
+{
+    ATermList outs = ATempty;
+    for (DeriveOutputs::const_iterator i = derive.outputs.begin();
+         i != derive.outputs.end(); i++)
+        outs = ATinsert(outs,
+            ATmake("(<str>, <str>)", 
+                i->first.c_str(), ((string) i->second).c_str()));
+    
+    ATermList env = ATempty;
+    for (StringPairs::const_iterator i = derive.env.begin();
+         i != derive.env.end(); i++)
+        env = ATinsert(env,
+            ATmake("(<str>, <str>)", 
+                i->first.c_str(), i->second.c_str()));
+
+    return ATmake("Derive(<term>, <term>, <str>, <str>, <term>)",
+        ATreverse(outs),
+        unparseIds(derive.inputs),
+        derive.builder.c_str(),
+        derive.platform.c_str(),
+        ATreverse(env));
+}
+
+
+ATerm unparseFState(const FState & fs)
+{
+    if (fs.type == FState::fsSlice)
+        return unparseSlice(fs.slice);
+    else if (fs.type == FState::fsDerive)
+        return unparseDerive(fs.derive);
+    else abort();
+}

src/fstate.hh

@@ -0,0 +1,75 @@
+#ifndef __FSTATE_H
+#define __FSTATE_H
+
+extern "C" {
+#include <aterm2.h>
+}
+
+#include "store.hh"
+
+
+/* Abstract syntax of fstate-expressions. */
+
+typedef list<FSId> FSIds;
+
+struct SliceElem
+{
+    string path;
+    FSId id;
+    FSIds refs;
+};
+
+typedef list<SliceElem> SliceElems;
+
+struct Slice
+{
+    FSIds roots;
+    SliceElems elems;
+};
+
+typedef pair<string, FSId> DeriveOutput;
+typedef pair<string, string> StringPair;
+typedef list<DeriveOutput> DeriveOutputs;
+typedef list<StringPair> StringPairs;
+
+struct Derive
+{
+    DeriveOutputs outputs;
+    FSIds inputs;
+    string builder;
+    string platform;
+    StringPairs env;
+};
+
+struct FState
+{
+    enum { fsSlice, fsDerive } type;
+    Slice slice;
+    Derive derive;
+};
+
+
+/* Return a canonical textual representation of an expression. */
+string printTerm(ATerm t);
+
+/* Throw an exception with an error message containing the given
+   aterm. */
+Error badTerm(const format & f, ATerm t);
+
+/* Hash an aterm. */
+Hash hashTerm(ATerm t);
+
+/* Read an aterm from disk, given its id. */
+ATerm termFromId(const FSId & id);
+
+/* Write an aterm to the Nix store directory, and return its hash. */
+FSId writeTerm(ATerm t, const string & suffix, FSId id = FSId());
+
+/* Parse an fstate-expression. */
+FState parseFState(ATerm t);
+
+/* Parse an fstate-expression. */
+ATerm unparseFState(const FState & fs);
+
+
+#endif /* !__FSTATE_H */

src/globals.cc

@@ -0,0 +1,23 @@
+#include "globals.hh"
+#include "db.hh"
+
+
+string dbPath2Id = "path2id";
+string dbId2Paths = "id2paths";
+string dbSuccessors = "successors";
+string dbSubstitutes = "substitutes";
+
+
+string nixStore = "/UNINIT";
+string nixDataDir = "/UNINIT";
+string nixLogDir = "/UNINIT";
+string nixDB = "/UNINIT";
+
+
+void initDB()
+{
+    createDB(nixDB, dbPath2Id);
+    createDB(nixDB, dbId2Paths);
+    createDB(nixDB, dbSuccessors);
+    createDB(nixDB, dbSubstitutes);
+}

src/globals.hh

@@ -0,0 +1,72 @@
+#ifndef __GLOBALS_H
+#define __GLOBALS_H
+
+#include <string>
+
+using namespace std;
+
+
+/* Database names. */
+
+/* dbPath2Id :: Path -> FSId
+
+   Each pair (p, id) records that path $p$ contains an expansion of
+   $id$. */
+extern string dbPath2Id;
+
+
+/* dbId2Paths :: FSId -> [Path]
+
+   A mapping from ids to lists of paths. */
+extern string dbId2Paths;
+
+
+/* dbSuccessors :: FSId -> FSId
+
+   Each pair $(id_1, id_2)$ in this mapping records the fact that a
+   successor of an fstate expression stored in a file with identifier
+   $id_1$ is stored in a file with identifier $id_2$.
+
+   Note that a term $y$ is successor of $x$ iff there exists a
+   sequence of rewrite steps that rewrites $x$ into $y$.
+*/
+extern string dbSuccessors;
+
+
+/* dbSubstitutes :: FSId -> [FSId]
+
+   Each pair $(id, [ids])$ tells Nix that it can realise any of the
+   fstate expressions referenced by the identifiers in $ids$ to
+   generate a path with identifier $id$.
+
+   The main purpose of this is for distributed caching of derivates.
+   One system can compute a derivate with hash $h$ and put it on a
+   website (as a Nix archive), for instance, and then another system
+   can register a substitute for that derivate.  The substitute in
+   this case might be an fstate expression that fetches the Nix
+   archive. 
+*/
+extern string dbSubstitutes;
+
+
+/* Path names. */
+
+/* nixStore is the directory where we generally store atomic and
+   derived files. */
+extern string nixStore;
+
+extern string nixDataDir; /* !!! fix */
+
+/* nixLogDir is the directory where we log various operations. */ 
+extern string nixLogDir;
+
+/* nixDB is the file name of the Berkeley DB database where we
+   maintain the dbXXX mappings. */
+extern string nixDB;
+
+
+/* Initialize the databases. */
+void initDB();
+
+
+#endif /* !__GLOBALS_H */

src/hash.cc

@@ -1,20 +1,20 @@
+#include <iostream>
+
 extern "C" {
 #include "md5.h"
 }
 
 #include "hash.hh"
-#include <iostream>
+#include "archive.hh"
 
 
-/* Create a zeroed hash object. */
 Hash::Hash()
 {
     memset(hash, 0, sizeof(hash));
 }
 
 
-/* Check whether two hash are equal. */
-bool Hash::operator == (Hash & h2)
+bool Hash::operator == (const Hash & h2) const
 {
     for (unsigned int i = 0; i < hashSize; i++)
         if (hash[i] != h2.hash[i]) return false;
@@ -22,14 +22,22 @@ bool Hash::operator == (Hash & h2)
 }
 
 
-/* Check whether two hash are not equal. */
-bool Hash::operator != (Hash & h2)
+bool Hash::operator != (const Hash & h2) const
 {
     return !(*this == h2);
 }
 
 
-/* Convert a hash code into a hexadecimal representation. */
+bool Hash::operator < (const Hash & h) const
+{
+    for (unsigned int i = 0; i < hashSize; i++) {
+        if (hash[i] < h.hash[i]) return true;
+        if (hash[i] > h.hash[i]) return false;
+    }
+    return false;
+}
+
+
 Hash::operator string() const
 {
     ostringstream str;
@@ -42,10 +50,11 @@ Hash::operator string() const
 }
 
     
-/* Parse a hexadecimal representation of a hash code. */
 Hash parseHash(const string & s)
 {
     Hash hash;
+    if (s.length() != Hash::hashSize * 2)
+        throw BadRefError("invalid hash: " + s);
     for (unsigned int i = 0; i < Hash::hashSize; i++) {
         string s2(s, i * 2, 2);
         if (!isxdigit(s2[0]) || !isxdigit(s2[1])) 
@@ -59,7 +68,6 @@ Hash parseHash(const string & s)
 }
 
 
-/* Verify that a reference is valid (that is, is a MD5 hash code). */
 bool isHash(const string & s)
 {
     if (s.length() != 32) return false;
@@ -73,15 +81,44 @@ bool isHash(const string & s)
 }
 
 
-/* Compute the MD5 hash of a file. */
+Hash hashString(const string & s)
+{
+    Hash hash;
+    md5_buffer(s.c_str(), s.length(), hash.hash);
+    return hash;
+}
+
+
 Hash hashFile(const string & fileName)
 {
     Hash hash;
     FILE * file = fopen(fileName.c_str(), "rb");
     if (!file)
-        throw Error("file `" + fileName + "' does not exist");
+        throw SysError("file `" + fileName + "' does not exist");
     int err = md5_stream(file, hash.hash);
     fclose(file);
-    if (err) throw Error("cannot hash file");
+    if (err) throw SysError("cannot hash file " + fileName);
+    return hash;
+}
+
+
+struct HashSink : DumpSink
+{
+    struct md5_ctx ctx;
+    virtual void operator ()
+        (const unsigned char * data, unsigned int len)
+    {
+        md5_process_bytes(data, len, &ctx);
+    }
+};
+
+
+Hash hashPath(const string & path)
+{
+    Hash hash;
+    HashSink sink;
+    md5_init_ctx(&sink.ctx);
+    dumpPath(path, sink);
+    md5_finish_ctx(&sink.ctx, hash.hash);
     return hash;
 }

src/hash.hh

@@ -13,9 +13,19 @@ struct Hash
     static const unsigned int hashSize = 16;
     unsigned char hash[hashSize];
 
+    /* Create a zeroed hash object. */
     Hash();
-    bool operator == (Hash & h2);
-    bool operator != (Hash & h2);
+
+    /* Check whether two hash are equal. */
+    bool operator == (const Hash & h2) const;
+
+    /* Check whether two hash are not equal. */
+    bool operator != (const Hash & h2) const;
+
+    /* For sorting. */
+    bool operator < (const Hash & h) const;
+
+    /* Convert a hash code into a hexadecimal representation. */
     operator string() const;
 };
 
@@ -27,8 +37,22 @@ public:
 };
 
 
+/* Parse a hexadecimal representation of a hash code. */
 Hash parseHash(const string & s);
+
+/* Verify that the given string is a valid hash code. */
 bool isHash(const string & s);
+
+/* Compute the hash of the given string. */
+Hash hashString(const string & s);
+
+/* Compute the hash of the given file. */
 Hash hashFile(const string & fileName);
 
+/* Compute the hash of the given path.  The hash is defined as
+   md5(dump(path)).
+*/
+Hash hashPath(const string & path);
+
+
 #endif /* !__HASH_H */

src/nix-hash.cc

@@ -0,0 +1,16 @@
+#include <iostream>
+
+#include "hash.hh"
+#include "shared.hh"
+
+
+void run(Strings args)
+{
+    for (Strings::iterator it = args.begin();
+         it != args.end(); it++)
+        cout << format("%1%\n") % (string) hashPath(*it);
+}
+
+
+string programId = "nix-hash";
+

src/nix-help.txt

@@ -0,0 +1,36 @@
+nix [OPTIONS...] [ARGUMENTS...]
+
+Operations:
+
+  --install / -i: realise an fstate
+  --delete / -d: delete paths from the Nix store
+  --add / -A: copy a path to the Nix store
+  --query / -q: query information
+
+  --successor: register a successor expression
+  --substitute: register a substitute expression
+
+  --dump: dump a path as a Nix archive
+  --restore: restore a path from a Nix archive
+
+  --init: initialise the Nix database
+  --verify: verify Nix structures
+
+  --version: output version information
+  --help: display help
+
+Source selection for --install, --dump:
+
+  --path / -p: by file name  !!! -> path
+
+Query flags:
+
+  --list / -l: query the output paths (roots) of an fstate (default)
+  --requisites / -r: print all paths necessary to realise expression
+  --generators / -g: find expressions producing a subset of given ids
+  --expansion / -e: print a path containing id
+  --graph: print a dot graph rooted at given ids
+
+Options:
+
+  --verbose / -v: verbose operation (may be repeated)

src/normalise.cc

@@ -0,0 +1,329 @@
+#include <map>
+
+#include "normalise.hh"
+#include "references.hh"
+#include "db.hh"
+#include "exec.hh"
+#include "globals.hh"
+
+
+void registerSuccessor(const FSId & id1, const FSId & id2)
+{
+    setDB(nixDB, dbSuccessors, id1, id2);
+}
+
+
+static FSId storeSuccessor(const FSId & id1, ATerm sc)
+{
+    FSId id2 = writeTerm(sc, "-s-" + (string) id1);
+    registerSuccessor(id1, id2);
+    return id2;
+}
+
+
+typedef set<FSId> FSIdSet;
+
+
+FSId normaliseFState(FSId id, FSIdSet pending)
+{
+    Nest nest(lvlTalkative, format("normalising fstate %1%") % (string) id);
+
+    /* Try to substitute $id$ by any known successors in order to
+       speed up the rewrite process. */
+    string idSucc;
+    while (queryDB(nixDB, dbSuccessors, id, idSucc)) {
+        debug(format("successor %1% -> %2%") % (string) id % idSucc);
+        id = parseHash(idSucc);
+    }
+
+    /* Get the fstate expression. */
+    FState fs = parseFState(termFromId(id));
+
+    /* It this is a normal form (i.e., a slice) we are done. */
+    if (fs.type == FState::fsSlice) return id;
+    
+    /* Otherwise, it's a derivation. */
+
+    /* Right platform? */
+    if (fs.derive.platform != thisSystem)
+        throw Error(format("a `%1%' is required, but I am a `%2%'")
+            % fs.derive.platform % thisSystem);
+        
+    /* Realise inputs (and remember all input paths). */
+    typedef map<string, SliceElem> ElemMap;
+
+    ElemMap inMap;
+
+    for (FSIds::iterator i = fs.derive.inputs.begin();
+         i != fs.derive.inputs.end(); i++) {
+        FSId nf = normaliseFState(*i, pending);
+        realiseSlice(nf, pending);
+        FState fs = parseFState(termFromId(nf));
+        if (fs.type != FState::fsSlice) abort();
+        for (SliceElems::iterator j = fs.slice.elems.begin();
+             j != fs.slice.elems.end(); j++)
+            inMap[j->path] = *j;
+    }
+
+    Strings inPaths;
+    for (ElemMap::iterator i = inMap.begin(); i != inMap.end(); i++)
+        inPaths.push_back(i->second.path);
+
+    /* Build the environment. */
+    Environment env;
+    for (StringPairs::iterator i = fs.derive.env.begin();
+         i != fs.derive.env.end(); i++)
+        env[i->first] = i->second;
+
+    /* Parse the outputs. */
+    typedef map<string, FSId> OutPaths;
+    OutPaths outPaths;
+    for (DeriveOutputs::iterator i = fs.derive.outputs.begin();
+         i != fs.derive.outputs.end(); i++)
+    {
+        debug(format("building %1% in `%2%'") % (string) i->second % i->first);
+        outPaths[i->first] = i->second;
+        inPaths.push_back(i->first);
+    }
+
+    /* We can skip running the builder if we can expand all output
+       paths from their ids. */
+    bool fastBuild = true;
+    for (OutPaths::iterator i = outPaths.begin(); 
+         i != outPaths.end(); i++)
+    {
+        try {
+            expandId(i->second, i->first, "/", pending);
+        } catch (Error & e) {
+            debug(format("fast build failed for `%1%': %2%")
+		  % i->first % e.what());
+            fastBuild = false;
+            break;
+        }
+    }
+
+    if (!fastBuild) {
+
+        /* Check that none of the outputs exist. */
+        for (OutPaths::iterator i = outPaths.begin(); 
+             i != outPaths.end(); i++)
+            if (pathExists(i->first))
+                throw Error(format("path `%1%' exists") % i->first);
+
+        /* Run the builder. */
+        msg(lvlChatty, format("building..."));
+        runProgram(fs.derive.builder, env);
+        msg(lvlChatty, format("build completed"));
+        
+    } else
+        msg(lvlChatty, format("fast build succesful"));
+
+    /* Check whether the output paths were created, and register each
+       one. */
+    FSIdSet used;
+    for (OutPaths::iterator i = outPaths.begin(); 
+         i != outPaths.end(); i++)
+    {
+        string path = i->first;
+        if (!pathExists(path))
+            throw Error(format("path `%1%' does not exist") % path);
+        registerPath(path, i->second);
+        fs.slice.roots.push_back(i->second);
+
+        Strings refs = filterReferences(path, inPaths);
+
+        SliceElem elem;
+        elem.path = path;
+        elem.id = i->second;
+
+        for (Strings::iterator j = refs.begin(); j != refs.end(); j++) {
+            ElemMap::iterator k;
+            OutPaths::iterator l;
+            if ((k = inMap.find(*j)) != inMap.end()) {
+                elem.refs.push_back(k->second.id);
+                used.insert(k->second.id);
+                for (FSIds::iterator m = k->second.refs.begin();
+                     m != k->second.refs.end(); m++)
+                    used.insert(*m);
+            } else if ((l = outPaths.find(*j)) != outPaths.end()) {
+                elem.refs.push_back(l->second);
+                used.insert(l->second);
+            } else 
+                throw Error(format("unknown referenced path `%1%'") % *j);
+        }
+
+        fs.slice.elems.push_back(elem);
+    }
+
+    for (ElemMap::iterator i = inMap.begin();
+         i != inMap.end(); i++)
+    {
+        FSIdSet::iterator j = used.find(i->second.id);
+        if (j == used.end())
+            debug(format("NOT referenced: `%1%'") % i->second.path);
+        else {
+            debug(format("referenced: `%1%'") % i->second.path);
+            fs.slice.elems.push_back(i->second);
+        }
+    }
+
+    fs.type = FState::fsSlice;
+    ATerm nf = unparseFState(fs);
+    msg(lvlVomit, format("normal form: %1%") % printTerm(nf));
+    return storeSuccessor(id, nf);
+}
+
+
+void realiseSlice(const FSId & id, FSIdSet pending)
+{
+    Nest nest(lvlDebug, 
+        format("realising slice %1%") % (string) id);
+
+    FState fs = parseFState(termFromId(id));
+    if (fs.type != FState::fsSlice)
+        throw Error(format("expected slice in %1%") % (string) id);
+    
+    /* Perhaps all paths already contain the right id? */
+
+    bool missing = false;
+    for (SliceElems::const_iterator i = fs.slice.elems.begin();
+         i != fs.slice.elems.end(); i++)
+    {
+        SliceElem elem = *i;
+        string id;
+        if (!queryDB(nixDB, dbPath2Id, elem.path, id)) {
+            if (pathExists(elem.path))
+                throw Error(format("path `%1%' obstructed") % elem.path);
+            missing = true;
+            break;
+        }
+        if (parseHash(id) != elem.id)
+            throw Error(format("path `%1%' obstructed") % elem.path);
+    }
+
+    if (!missing) {
+        debug(format("already installed"));
+        return;
+    }
+
+    /* For each element, expand its id at its path. */
+    for (SliceElems::const_iterator i = fs.slice.elems.begin();
+         i != fs.slice.elems.end(); i++)
+    {
+        SliceElem elem = *i;
+        debug(format("expanding %1% in `%2%'") % (string) elem.id % elem.path);
+        expandId(elem.id, elem.path, "/", pending);
+    }
+}
+
+
+Strings fstatePaths(const FSId & id)
+{
+    Strings paths;
+
+    FState fs = parseFState(termFromId(id));
+
+    if (fs.type == FState::fsSlice) {
+        /* !!! fix complexity */
+        for (FSIds::const_iterator i = fs.slice.roots.begin();
+             i != fs.slice.roots.end(); i++)
+            for (SliceElems::const_iterator j = fs.slice.elems.begin();
+                 j != fs.slice.elems.end(); j++)
+                if (*i == j->id) paths.push_back(j->path);
+    }
+
+    else if (fs.type == FState::fsDerive) {
+        for (DeriveOutputs::iterator i = fs.derive.outputs.begin();
+             i != fs.derive.outputs.end(); i++)
+            paths.push_back(i->first);
+    }
+    
+    else abort();
+
+    return paths;
+}
+
+
+static void fstateRequisitesSet(const FSId & id, 
+    bool includeExprs, bool includeSuccessors, StringSet & paths)
+{
+    FState fs = parseFState(termFromId(id));
+
+    if (fs.type == FState::fsSlice) {
+        for (SliceElems::iterator i = fs.slice.elems.begin();
+             i != fs.slice.elems.end(); i++)
+            paths.insert(i->path);
+    }
+    
+    else if (fs.type == FState::fsDerive) {
+        for (FSIds::iterator i = fs.derive.inputs.begin();
+             i != fs.derive.inputs.end(); i++)
+            fstateRequisitesSet(*i,
+                includeExprs, includeSuccessors, paths);
+    }
+
+    else abort();
+
+    if (includeExprs) 
+        paths.insert(expandId(id));
+
+    string idSucc;
+    if (includeSuccessors &&
+        queryDB(nixDB, dbSuccessors, id, idSucc))
+        fstateRequisitesSet(parseHash(idSucc), 
+            includeExprs, includeSuccessors, paths);
+}
+
+
+Strings fstateRequisites(const FSId & id,
+    bool includeExprs, bool includeSuccessors)
+{
+    StringSet paths;
+    fstateRequisitesSet(id, includeExprs, includeSuccessors, paths);
+    return Strings(paths.begin(), paths.end());
+}
+
+
+FSIds findGenerators(const FSIds & _ids)
+{
+    FSIdSet ids(_ids.begin(), _ids.end());
+    FSIds generators;
+
+    /* !!! hack; for performance, we just look at the rhs of successor
+       mappings, since we know that those are Nix expressions. */
+
+    Strings sucs;
+    enumDB(nixDB, dbSuccessors, sucs);
+
+    for (Strings::iterator i = sucs.begin();
+         i != sucs.end(); i++)
+    {
+        string s;
+        if (!queryDB(nixDB, dbSuccessors, *i, s)) continue;
+        FSId id = parseHash(s);
+
+        FState fs;
+        try {
+            /* !!! should substitutes be used? */
+            fs = parseFState(termFromId(id));
+        } catch (...) { /* !!! only catch parse errors */
+            continue;
+        }
+
+        if (fs.type != FState::fsSlice) continue;
+        
+        bool okay = true;
+        for (SliceElems::const_iterator i = fs.slice.elems.begin();
+             i != fs.slice.elems.end(); i++)
+            if (ids.find(i->id) == ids.end()) {
+                okay = false;
+                break;
+            }
+        
+        if (!okay) continue;
+        
+        generators.push_back(id);
+    }
+
+    return generators;
+}

src/normalise.hh

@@ -0,0 +1,35 @@
+#ifndef __NORMALISE_H
+#define __NORMALISE_H
+
+#include "fstate.hh"
+
+
+/* Normalise an fstate-expression, that is, return an equivalent
+   slice.  (For the meaning of `pending', see expandId()). */
+FSId normaliseFState(FSId id, FSIdSet pending = FSIdSet());
+
+/* Realise a Slice in the file system. */
+void realiseSlice(const FSId & id, FSIdSet pending = FSIdSet());
+
+/* Get the list of root (output) paths of the given
+   fstate-expression. */
+Strings fstatePaths(const FSId & id);
+
+/* Get the list of paths that are required to realise the given
+   expression.  For a derive expression, this is the union of
+   requisites of the inputs; for a slice expression, it is the path of
+   each element in the slice.  If `includeExprs' is true, include the
+   paths of the Nix expressions themselves.  If `includeSuccessors' is
+   true, include the requisites of successors. */
+Strings fstateRequisites(const FSId & id,
+    bool includeExprs, bool includeSuccessors);
+
+/* Return the list of the ids of all known fstate-expressions whose
+   output ids are completely contained in `ids'. */
+FSIds findGenerators(const FSIds & ids);
+
+/* Register a successor. */
+void registerSuccessor(const FSId & id1, const FSId & id2);
+
+
+#endif /* !__NORMALISE_H */

src/references.cc

@@ -0,0 +1,109 @@
+#include <map>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <fcntl.h>
+
+#include "references.hh"
+#include "hash.hh"
+
+
+static void search(const string & s,
+    Strings & ids, Strings & seen)
+{
+    for (Strings::iterator i = ids.begin();
+         i != ids.end(); )
+    {
+        if (s.find(*i) == string::npos)
+            i++;
+        else {
+            debug(format("found reference to `%1%'") % *i);
+            seen.push_back(*i);
+            i = ids.erase(i);
+        }
+    }
+}
+
+
+void checkPath(const string & path,
+    Strings & ids, Strings & seen)
+{
+    struct stat st;
+    if (lstat(path.c_str(), &st))
+        throw SysError(format("getting attributes of path `%1%'") % path);
+
+    if (S_ISDIR(st.st_mode)) {
+        DIR * dir = opendir(path.c_str());
+
+        struct dirent * dirent;
+        while (errno = 0, dirent = readdir(dir)) {
+            string name = dirent->d_name;
+            if (name == "." || name == "..") continue;
+            search(name, ids, seen);
+            checkPath(path + "/" + name, ids, seen);
+        }
+
+        closedir(dir); /* !!! close on exception */
+    }
+
+    else if (S_ISREG(st.st_mode)) {
+        
+        debug(format("checking `%1%'") % path);
+
+        int fd = open(path.c_str(), O_RDONLY);
+        if (fd == -1) throw SysError(format("opening file `%1%'") % path);
+
+        unsigned char * buf = new unsigned char[st.st_size];
+
+        readFull(fd, buf, st.st_size);
+
+        search(string((char *) buf, st.st_size), ids, seen);
+        
+        delete buf; /* !!! autodelete */
+
+        close(fd); /* !!! close on exception */
+    }
+    
+    else if (S_ISLNK(st.st_mode)) {
+        char buf[st.st_size];
+        if (readlink(path.c_str(), buf, st.st_size) != st.st_size)
+            throw SysError(format("reading symbolic link `%1%'") % path);
+        search(string(buf, st.st_size), ids, seen);
+    }
+    
+    else throw Error(format("unknown file type: %1%") % path);
+}
+
+
+Strings filterReferences(const string & path, const Strings & paths)
+{
+    map<string, string> backMap;
+    Strings ids;
+    Strings seen;
+
+    /* For efficiency (and a higher hit rate), just search for the
+       hash part of the file name.  (This assumes that all references
+       have the form `HASH-bla'). */
+    for (Strings::const_iterator i = paths.begin();
+         i != paths.end(); i++)
+    {
+        string s = string(baseNameOf(*i), 0, 32);
+        parseHash(s);
+        ids.push_back(s);
+        backMap[s] = *i;
+    }
+
+    checkPath(path, ids, seen);
+
+    Strings found;
+    for (Strings::iterator i = seen.begin(); i != seen.end(); i++)
+    {
+        map<string, string>::iterator j;
+        if ((j = backMap.find(*i)) == backMap.end()) abort();
+        found.push_back(j->second);
+    }
+
+    return found;
+}

src/references.hh

@@ -0,0 +1,10 @@
+#ifndef __VALUES_H
+#define __VALUES_H
+
+#include "util.hh"
+
+
+Strings filterReferences(const string & path, const Strings & refs);
+
+
+#endif /* !__VALUES_H */

src/shared.cc

@@ -0,0 +1,76 @@
+#include <iostream>
+#include <cctype>
+
+extern "C" {
+#include <aterm2.h>
+}
+
+#include "globals.hh"
+#include "shared.hh"
+
+#include "config.h"
+
+
+/* Initialize and reorder arguments, then call the actual argument
+   processor. */
+static void initAndRun(int argc, char * * argv)
+{
+    /* Setup Nix paths. */
+    nixStore = NIX_STORE_DIR;
+    nixDataDir = NIX_DATA_DIR;
+    nixLogDir = NIX_LOG_DIR;
+    nixDB = (string) NIX_STATE_DIR + "/nixstate.db";
+
+    /* Put the arguments in a vector. */
+    Strings args;
+    while (argc--) args.push_back(*argv++);
+    args.erase(args.begin());
+    
+    /* Expand compound dash options (i.e., `-qlf' -> `-q -l -f'). */
+    for (Strings::iterator it = args.begin();
+         it != args.end(); )
+    {
+        string arg = *it;
+        if (arg.length() > 2 && arg[0] == '-' && arg[1] != '-') {
+            for (unsigned int i = 1; i < arg.length(); i++)
+                if (isalpha(arg[i]))
+                    args.insert(it, (string) "-" + arg[i]);
+                else {
+                    args.insert(it, string(arg, i));
+                    break;
+                }
+            it = args.erase(it);
+        } else it++;
+    }
+
+    run(args);
+}
+
+
+int main(int argc, char * * argv)
+{
+    /* ATerm setup. */
+    ATerm bottomOfStack;
+    ATinit(argc, argv, &bottomOfStack);
+
+    try {
+        initAndRun(argc, argv);
+    } catch (UsageError & e) {
+        msg(lvlError, 
+            format(
+                "error: %1%\n"
+                "Try `%2% --help' for more information.")
+            % e.what() % programId);
+        return 1;
+    } catch (Error & e) {
+        msg(lvlError, format("error: %1%") % e.msg());
+        return 1;
+    } catch (exception & e) {
+        msg(lvlError, format("error: %1%") % e.what());
+        return 1;
+    }
+
+    return 0;
+}
+
+

src/shared.hh

@@ -0,0 +1,15 @@
+#ifndef __SHARED_H
+#define __SHARED_H
+
+#include <string>
+
+#include "util.hh"
+
+
+void run(Strings args);
+
+
+extern string programId;
+
+
+#endif /* !__SHARED_H */

src/store.cc

@@ -0,0 +1,382 @@
+#include <iostream>
+
+#include <sys/types.h>
+#include <sys/wait.h>
+
+#include "store.hh"
+#include "globals.hh"
+#include "db.hh"
+#include "archive.hh"
+#include "normalise.hh"
+
+
+struct CopySink : DumpSink
+{
+    int fd;
+    virtual void operator () (const unsigned char * data, unsigned int len)
+    {
+        writeFull(fd, data, len);
+    }
+};
+
+
+struct CopySource : RestoreSource
+{
+    int fd;
+    virtual void operator () (unsigned char * data, unsigned int len)
+    {
+        readFull(fd, data, len);
+    }
+};
+
+
+void copyPath(string src, string dst)
+{
+    /* Unfortunately C++ doesn't support coprocedures, so we have no
+       nice way to chain CopySink and CopySource together.  Instead we
+       fork off a child to run the sink.  (Fork-less platforms should
+       use a thread). */
+
+    /* Create a pipe. */
+    int fds[2];
+    if (pipe(fds) == -1) throw SysError("creating pipe");
+
+    /* Fork. */
+    pid_t pid;
+    switch (pid = fork()) {
+
+    case -1:
+        throw SysError("unable to fork");
+
+    case 0: /* child */
+        try {
+            close(fds[1]);
+            CopySource source;
+            source.fd = fds[0];
+            restorePath(dst, source);
+            _exit(0);
+        }  catch (exception & e) {
+            cerr << "error: " << e.what() << endl;
+        }
+        _exit(1);        
+    }
+
+    close(fds[0]);
+    
+    /* Parent. */
+
+    CopySink sink;
+    sink.fd = fds[1];
+    dumpPath(src, sink);
+
+    /* Wait for the child to finish. */
+    int status;
+    if (waitpid(pid, &status, 0) != pid)
+        throw SysError("waiting for child");
+
+    if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
+        throw Error("cannot copy file: child died");
+}
+
+
+void registerSubstitute(const FSId & srcId, const FSId & subId)
+{
+#if 0
+    Strings subs;
+    queryListDB(nixDB, dbSubstitutes, srcId, subs); /* non-existence = ok */
+
+    for (Strings::iterator it = subs.begin(); it != subs.end(); it++)
+        if (parseHash(*it) == subId) return;
+    
+    subs.push_back(subId);
+    
+    setListDB(nixDB, dbSubstitutes, srcId, subs);
+#endif
+
+    /* For now, accept only one substitute per id. */
+    Strings subs;
+    subs.push_back(subId);
+    setListDB(nixDB, dbSubstitutes, srcId, subs);
+}
+
+
+void registerPath(const string & _path, const FSId & id)
+{
+    string path(canonPath(_path));
+
+    setDB(nixDB, dbPath2Id, path, id);
+
+    Strings paths;
+    queryListDB(nixDB, dbId2Paths, id, paths); /* non-existence = ok */
+
+    for (Strings::iterator it = paths.begin();
+         it != paths.end(); it++)
+        if (*it == path) return;
+    
+    paths.push_back(path);
+    
+    setListDB(nixDB, dbId2Paths, id, paths);
+}
+
+
+void unregisterPath(const string & _path)
+{
+    string path(canonPath(_path));
+
+    string _id;
+    if (!queryDB(nixDB, dbPath2Id, path, _id))
+        return;
+    FSId id(parseHash(_id));
+
+    delDB(nixDB, dbPath2Id, path);
+
+    /* begin transaction */
+    
+    Strings paths, paths2;
+    queryListDB(nixDB, dbId2Paths, id, paths); /* non-existence = ok */
+
+    bool changed = false;
+    for (Strings::iterator it = paths.begin();
+         it != paths.end(); it++)
+        if (*it != path) paths2.push_back(*it); else changed = true;
+
+    if (changed)
+        setListDB(nixDB, dbId2Paths, id, paths2);
+
+    /* end transaction */
+
+}
+
+
+bool queryPathId(const string & path, FSId & id)
+{
+    string s;
+    if (!queryDB(nixDB, dbPath2Id, absPath(path), s)) return false;
+    id = parseHash(s);
+    return true;
+}
+
+
+bool isInPrefix(const string & path, const string & _prefix)
+{
+    string prefix = canonPath(_prefix + "/");
+    return string(path, 0, prefix.size()) == prefix;
+}
+
+
+string expandId(const FSId & id, const string & target,
+    const string & prefix, FSIdSet pending)
+{
+    Nest nest(lvlDebug, format("expanding %1%") % (string) id);
+
+    Strings paths;
+
+    if (!target.empty() && !isInPrefix(target, prefix))
+        abort();
+
+    queryListDB(nixDB, dbId2Paths, id, paths);
+
+    /* Pick one equal to `target'. */
+    if (!target.empty()) {
+
+        for (Strings::iterator i = paths.begin();
+             i != paths.end(); i++)
+        {
+            string path = *i;
+            if (path == target && pathExists(path))
+                return path;
+        }
+        
+    }
+
+    /* Arbitrarily pick the first one that exists and isn't stale. */
+    for (Strings::iterator it = paths.begin();
+         it != paths.end(); it++)
+    {
+        string path = *it;
+        if (isInPrefix(path, prefix) && pathExists(path)) {
+            if (target.empty())
+                return path;
+            else {
+                copyPath(path, target);
+                registerPath(target, id);
+                return target;
+            }
+        }
+    }
+
+    if (pending.find(id) != pending.end())
+        throw Error(format("id %1% already being expanded") % (string) id);
+    pending.insert(id);
+
+    /* Try to realise the substitutes, but only if this id is not
+       already being realised by a substitute. */
+    Strings subs;
+    queryListDB(nixDB, dbSubstitutes, id, subs); /* non-existence = ok */
+
+    for (Strings::iterator it = subs.begin(); it != subs.end(); it++) {
+        FSId subId = parseHash(*it);
+
+        debug(format("trying substitute %1%") % (string) subId);
+
+        realiseSlice(normaliseFState(subId, pending), pending);
+
+        return expandId(id, target, prefix, pending);
+    }
+    
+    throw Error(format("cannot expand id `%1%'") % (string) id);
+}
+
+    
+void addToStore(string srcPath, string & dstPath, FSId & id,
+    bool deterministicName)
+{
+    srcPath = absPath(srcPath);
+    id = hashPath(srcPath);
+
+    string baseName = baseNameOf(srcPath);
+    dstPath = canonPath(nixStore + "/" + (string) id + "-" + baseName);
+
+    try {
+        /* !!! should not use the substitutes! */
+        dstPath = expandId(id, deterministicName ? dstPath : "", nixStore);
+        return;
+    } catch (...) {
+    }
+    
+    copyPath(srcPath, dstPath);
+    registerPath(dstPath, id);
+}
+
+
+void deleteFromStore(const string & path)
+{
+    string prefix =  + "/";
+    if (!isInPrefix(path, nixStore))
+        throw Error(format("path %1% is not in the store") % path);
+
+    unregisterPath(path);
+
+    deletePath(path);
+}
+
+
+void verifyStore()
+{
+    Strings paths;
+    enumDB(nixDB, dbPath2Id, paths);
+
+    for (Strings::iterator i = paths.begin();
+         i != paths.end(); i++)
+    {
+        bool erase = true;
+        string path = *i;
+
+        if (!pathExists(path)) {
+            debug(format("path `%1%' disappeared") % path);
+        }
+
+        else {
+            string id;
+            if (!queryDB(nixDB, dbPath2Id, path, id)) abort();
+
+            Strings idPaths;
+            queryListDB(nixDB, dbId2Paths, id, idPaths);
+
+            bool found = false;
+            for (Strings::iterator j = idPaths.begin();     
+                 j != idPaths.end(); j++)
+                if (path == *j) {
+                    found = true;
+                    break;
+                }
+
+            if (found)
+                erase = false;
+            else
+                /* !!! perhaps we should add path to idPaths? */
+                debug(format("reverse mapping for path `%1%' missing") % path);
+        }
+
+        if (erase) delDB(nixDB, dbPath2Id, path);
+    }
+
+    Strings ids;
+    enumDB(nixDB, dbId2Paths, ids);
+
+    for (Strings::iterator i = ids.begin();
+         i != ids.end(); i++)
+    {
+        FSId id = parseHash(*i);
+
+        Strings idPaths;
+        queryListDB(nixDB, dbId2Paths, id, idPaths);
+
+        for (Strings::iterator j = idPaths.begin();     
+             j != idPaths.end(); )
+        {
+            string id2;
+            if (!queryDB(nixDB, dbPath2Id, *j, id2) || 
+                id != parseHash(id2)) {
+                debug(format("erasing path `%1%' from mapping for id %2%") 
+                    % *j % (string) id);
+                j = idPaths.erase(j);
+            } else j++;
+        }
+
+        setListDB(nixDB, dbId2Paths, id, idPaths);
+    }
+
+    
+    Strings subs;
+    enumDB(nixDB, dbSubstitutes, subs);
+
+    for (Strings::iterator i = subs.begin();
+         i != subs.end(); i++)
+    {
+        FSId srcId = parseHash(*i);
+
+        Strings subIds;
+        queryListDB(nixDB, dbSubstitutes, srcId, subIds);
+
+        for (Strings::iterator j = subIds.begin();     
+             j != subIds.end(); )
+        {
+            FSId subId = parseHash(*j);
+            
+            Strings subPaths;
+            queryListDB(nixDB, dbId2Paths, subId, subPaths);
+            if (subPaths.size() == 0) {
+                debug(format("erasing substitute %1% for %2%") 
+                    % (string) subId % (string) srcId);
+                j = subIds.erase(j);
+            } else j++;
+        }
+
+        setListDB(nixDB, dbSubstitutes, srcId, subIds);
+    }
+
+    Strings sucs;
+    enumDB(nixDB, dbSuccessors, sucs);
+
+    for (Strings::iterator i = sucs.begin();
+         i != sucs.end(); i++)
+    {
+        FSId id1 = parseHash(*i);
+
+        string id2;
+        if (!queryDB(nixDB, dbSuccessors, id1, id2)) abort();
+        
+        Strings id2Paths;
+        queryListDB(nixDB, dbId2Paths, id2, id2Paths);
+        if (id2Paths.size() == 0) {
+            Strings id2Subs;
+            queryListDB(nixDB, dbSubstitutes, id2, id2Subs);
+            if (id2Subs.size() == 0) {
+                debug(format("successor %1% for %2% missing") 
+                    % id2 % (string) id1);
+                delDB(nixDB, dbSuccessors, (string) id1);
+            }
+        }
+    }
+}

src/store.hh

@@ -0,0 +1,51 @@
+#ifndef __STORE_H
+#define __STORE_H
+
+#include <string>
+
+#include "hash.hh"
+
+using namespace std;
+
+
+typedef Hash FSId;
+
+typedef set<FSId> FSIdSet;
+
+
+/* Copy a path recursively. */
+void copyPath(string src, string dst);
+
+/* Register a substitute. */
+void registerSubstitute(const FSId & srcId, const FSId & subId);
+
+/* Register a path keyed on its id. */
+void registerPath(const string & path, const FSId & id);
+
+/* Query the id of a path. */
+bool queryPathId(const string & path, FSId & id);
+
+/* Return a path whose contents have the given hash.  If target is
+   not empty, ensure that such a path is realised in target (if
+   necessary by copying from another location).  If prefix is not
+   empty, only return a path that is an descendent of prefix.
+
+   The list of pending ids are those that already being expanded.
+   This prevents infinite recursion for ids realised through a
+   substitute (since when we build the substitute, we would first try
+   to expand the id... kaboom!). */
+string expandId(const FSId & id, const string & target = "",
+    const string & prefix = "/", FSIdSet pending = FSIdSet());
+
+/* Copy a file to the nixStore directory and register it in dbRefs.
+   Return the hash code of the value. */
+void addToStore(string srcPath, string & dstPath, FSId & id,
+    bool deterministicName = false);
+
+/* Delete a value from the nixStore directory. */
+void deleteFromStore(const string & path);
+
+void verifyStore();
+
+
+#endif /* !__STORE_H */

src/test-builder-1.sh

@@ -0,0 +1,3 @@
+#! /bin/sh
+
+echo "Hello World" > $out

src/test-builder-2.sh

@@ -0,0 +1,9 @@
+#! /bin/sh
+
+echo "builder 2"
+
+mkdir $out || exit 1
+cd $out || exit 1
+echo "Hallo Wereld" > bla
+echo $builder >> bla
+echo $out >> bla

src/test-expr-1.nix

@@ -0,0 +1 @@
+Str("Hello World")

src/test.cc

@@ -1,16 +1,188 @@
 #include <iostream>
 
+#include <sys/stat.h>
+#include <sys/types.h>
+
 #include "hash.hh"
+#include "archive.hh"
+#include "util.hh"
+#include "normalise.hh"
+#include "globals.hh"
 
-int main(int argc, char * * argv)
+
+void realise(FSId id)
 {
-    Hash h = hashFile("/etc/passwd");
-    
-    cout << (string) h << endl;
-
-    h = parseHash("0b0ffd0538622bfe20b92c4aa57254d9");
-    
-    cout << (string) h << endl;
-
-    return 0;
+    Nest nest(lvlDebug, format("TEST: realising %1%") % (string) id);
+    realiseSlice(normaliseFState(id));
 }
+
+
+#if 0
+void realiseFail(FState fs)
+{
+    try {
+        realiseFState(fs);
+        abort();
+    } catch (Error e) {
+        cout << "error (expected): " << e.what() << endl;
+    }
+}
+#endif
+
+
+struct MySink : DumpSink
+{
+    virtual void operator () (const unsigned char * data, unsigned int len)
+    {
+        /* Don't use cout, it's slow as hell! */
+        writeFull(STDOUT_FILENO, data, len);
+    }
+};
+
+
+struct MySource : RestoreSource
+{
+    virtual void operator () (unsigned char * data, unsigned int len)
+    {
+        readFull(STDIN_FILENO, data, len);
+    }
+};
+
+
+void runTests()
+{
+    /* Hashing. */
+    string s = "0b0ffd0538622bfe20b92c4aa57254d9";
+    Hash h = parseHash(s);
+    if ((string) h != s) abort();
+
+    try {
+        h = parseHash("blah blah");
+        abort();
+    } catch (BadRefError err) { };
+
+    try {
+        h = parseHash("0b0ffd0538622bfe20b92c4aa57254d99");
+        abort();
+    } catch (BadRefError err) { };
+
+    /* Path canonicalisation. */
+    cout << canonPath("/./../././//") << endl;
+    cout << canonPath("/foo/bar") << endl;
+    cout << canonPath("///foo/////bar//") << endl;
+    cout << canonPath("/././/foo/////bar//.") << endl;
+    cout << canonPath("/foo////bar//..///x/") << endl;
+    cout << canonPath("/foo////bar//..//..//x/y/../z/") << endl;
+    cout << canonPath("/foo/bar/../../../..///") << endl;
+
+    /* Dumping. */
+
+#if 0
+    MySink sink;
+    dumpPath("scratch", sink);
+    cout << (string) hashPath("scratch") << endl;
+#endif
+
+    /* Restoring. */
+#if 0
+    MySource source;
+    restorePath("outdir", source);
+    cout << (string) hashPath("outdir") << endl;
+    return;
+#endif
+
+    /* Set up the test environment. */
+
+    mkdir("scratch", 0777);
+
+    string testDir = absPath("scratch");
+    cout << testDir << endl;
+
+    nixStore = testDir;
+    nixLogDir = testDir;
+    nixDB = testDir + "/db";
+
+    initDB();
+
+    /* Expression evaluation. */
+
+    FSId builder1id;
+    string builder1fn;
+    addToStore("./test-builder-1.sh", builder1fn, builder1id);
+
+    ATerm fs1 = ATmake(
+        "Slice([<str>], [(<str>, <str>, [])])",
+        ((string) builder1id).c_str(),
+        builder1fn.c_str(),
+        ((string) builder1id).c_str());
+    FSId fs1id = writeTerm(fs1, "");
+
+    realise(fs1id);
+    realise(fs1id);
+
+    ATerm fs2 = ATmake(
+        "Slice([<str>], [(<str>, <str>, [])])",
+        ((string) builder1id).c_str(),
+        (builder1fn + "_bla").c_str(),
+        ((string) builder1id).c_str());
+    FSId fs2id = writeTerm(fs2, "");
+
+    realise(fs2id);
+    realise(fs2id);
+
+    string out1id = hashString("foo"); /* !!! bad */
+    string out1fn = nixStore + "/" + (string) out1id + "-hello.txt";
+    ATerm fs3 = ATmake(
+        "Derive([(<str>, <str>)], [<str>], <str>, <str>, [(\"out\", <str>)])",
+        out1fn.c_str(),
+        ((string) out1id).c_str(),
+        ((string) fs1id).c_str(),
+        ((string) builder1fn).c_str(),
+        thisSystem.c_str(),
+        out1fn.c_str());
+    debug(printTerm(fs3));
+    FSId fs3id = writeTerm(fs3, "");
+
+    realise(fs3id);
+    realise(fs3id);
+
+
+    FSId builder4id;
+    string builder4fn;
+    addToStore("./test-builder-2.sh", builder4fn, builder4id);
+
+    ATerm fs4 = ATmake(
+        "Slice([<str>], [(<str>, <str>, [])])",
+        ((string) builder4id).c_str(),
+        builder4fn.c_str(),
+        ((string) builder4id).c_str());
+    FSId fs4id = writeTerm(fs4, "");
+
+    realise(fs4id);
+
+    string out5id = hashString("bar"); /* !!! bad */
+    string out5fn = nixStore + "/" + (string) out5id + "-hello2";
+    ATerm fs5 = ATmake(
+        "Derive([(<str>, <str>)], [<str>], <str>, <str>, [(\"out\", <str>), (\"builder\", <str>)])",
+        out5fn.c_str(),
+        ((string) out5id).c_str(),
+        ((string) fs4id).c_str(),
+        ((string) builder4fn).c_str(),
+        thisSystem.c_str(),
+        out5fn.c_str(),
+        ((string) builder4fn).c_str());
+    debug(printTerm(fs5));
+    FSId fs5id = writeTerm(fs5, "");
+
+    realise(fs5id);
+    realise(fs5id);
+}
+
+
+void run(Strings args)
+{
+    runTests();
+}
+
+
+string programId = "test";

src/util.cc

@@ -1,47 +1,192 @@
+#include <iostream>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+
 #include "util.hh"
 
 
 string thisSystem = SYSTEM;
-string nixHomeDir = "/nix";
-string nixHomeDirEnvVar = "NIX";
 
 
-
-string absPath(string filename, string dir)
+Error::Error(const format & f)
 {
-    if (filename[0] != '/') {
+    err = f.str();
+}
+
+
+SysError::SysError(const format & f)
+    : Error(format("%1%: %2%") % f.str() % strerror(errno))
+{
+}
+
+
+string absPath(string path, string dir)
+{
+    if (path[0] != '/') {
         if (dir == "") {
             char buf[PATH_MAX];
             if (!getcwd(buf, sizeof(buf)))
-                throw Error("cannot get cwd");
+                throw SysError("cannot get cwd");
             dir = buf;
         }
-        filename = dir + "/" + filename;
-        /* !!! canonicalise */
-        char resolved[PATH_MAX];
-        if (!realpath(filename.c_str(), resolved))
-            throw Error("cannot canonicalise path " + filename);
-        filename = resolved;
+        path = dir + "/" + path;
     }
-    return filename;
+    return canonPath(path);
 }
 
 
-/* Return the directory part of the given path, i.e., everything
-   before the final `/'. */
-string dirOf(string s)
+string canonPath(const string & path)
 {
-    unsigned int pos = s.rfind('/');
-    if (pos == string::npos) throw Error("invalid file name");
-    return string(s, 0, pos);
+    string s;
+
+    if (path[0] != '/')
+        throw Error(format("not an absolute path: `%1%'") % path);
+
+    string::const_iterator i = path.begin(), end = path.end();
+
+    while (1) {
+
+        /* Skip slashes. */
+        while (i != end && *i == '/') i++;
+        if (i == end) break;
+
+        /* Ignore `.'. */
+        if (*i == '.' && (i + 1 == end || i[1] == '/'))
+            i++;
+
+        /* If `..', delete the last component. */
+        else if (*i == '.' && i + 1 < end && i[1] == '.' && 
+            (i + 2 == end || i[2] == '/'))
+        {
+            if (!s.empty()) s.erase(s.rfind('/'));
+            i += 2;
+        }
+
+        /* Normal component; copy it. */
+        else {
+            s += '/';
+            while (i != end && *i != '/') s += *i++;
+        }
+    }
+
+    return s.empty() ? "/" : s;
 }
 
 
-/* Return the base name of the given path, i.e., everything following
-   the final `/'. */
-string baseNameOf(string s)
+string dirOf(string path)
 {
-    unsigned int pos = s.rfind('/');
-    if (pos == string::npos) throw Error("invalid file name");
-    return string(s, pos + 1);
+    unsigned int pos = path.rfind('/');
+    if (pos == string::npos)
+        throw Error(format("invalid file name: %1%") % path);
+    return string(path, 0, pos);
+}
+
+
+string baseNameOf(string path)
+{
+    unsigned int pos = path.rfind('/');
+    if (pos == string::npos)
+        throw Error(format("invalid file name %1% ") % path);
+    return string(path, pos + 1);
+}
+
+
+bool pathExists(const string & path)
+{
+    int res;
+    struct stat st;
+    res = stat(path.c_str(), &st);
+    if (!res) return true;
+    if (errno != ENOENT)
+        throw SysError(format("getting status of %1%") % path);
+    return false;
+}
+
+
+void deletePath(string path)
+{
+    struct stat st;
+    if (lstat(path.c_str(), &st))
+        throw SysError(format("getting attributes of path %1%") % path);
+
+    if (S_ISDIR(st.st_mode)) {
+        DIR * dir = opendir(path.c_str());
+
+        struct dirent * dirent;
+        while (errno = 0, dirent = readdir(dir)) {
+            string name = dirent->d_name;
+            if (name == "." || name == "..") continue;
+            deletePath(path + "/" + name);
+        }
+
+        closedir(dir); /* !!! close on exception */
+    }
+
+    if (remove(path.c_str()) == -1)
+        throw SysError(format("cannot unlink %1%") % path);
+}
+
+
+Verbosity verbosity = lvlError;
+
+static int nestingLevel = 0;
+
+
+Nest::Nest(Verbosity level, const format & f)
+{
+    if (level > verbosity)
+        nest = false;
+    else {
+        msg(level, f);
+        nest = true;
+        nestingLevel++;
+    }
+}
+
+
+Nest::~Nest()
+{
+    if (nest) nestingLevel--;
+}
+
+
+void msg(Verbosity level, const format & f)
+{
+    if (level > verbosity) return;
+    string spaces;
+    for (int i = 0; i < nestingLevel; i++)
+        spaces += "|   ";
+    cerr << format("%1%%2%\n") % spaces % f.str();
+}
+
+
+void debug(const format & f)
+{
+    msg(lvlDebug, f);
+}
+
+
+void readFull(int fd, unsigned char * buf, size_t count)
+{
+    while (count) {
+        ssize_t res = read(fd, (char *) buf, count);
+        if (res == -1) throw SysError("reading from file");
+        if (res == 0) throw Error("unexpected end-of-file");
+        count -= res;
+        buf += res;
+    }
+}
+
+
+void writeFull(int fd, const unsigned char * buf, size_t count)
+{
+    while (count) {
+        ssize_t res = write(fd, (char *) buf, count);
+        if (res == -1) throw SysError("writing to file");
+        count -= res;
+        buf += res;
+    }
 }

src/util.hh

@@ -2,46 +2,103 @@
 #define __UTIL_H
 
 #include <string>
-#include <vector>
+#include <list>
+#include <set>
 #include <sstream>
 
 #include <unistd.h>
 
+#include <boost/format.hpp>
+
 using namespace std;
+using namespace boost;
 
 
 class Error : public exception
 {
+protected:
     string err;
 public:
-    Error(string _err) { err = _err; }
+    Error(const format & f);
     ~Error() throw () { };
     const char * what() const throw () { return err.c_str(); }
+    const string & msg() const throw () { return err; }
+};
+
+class SysError : public Error
+{
+public:
+    SysError(const format & f);
 };
 
 class UsageError : public Error
 {
 public:
-    UsageError(string _err) : Error(_err) { };
+    UsageError(const format & f) : Error(f) { };
 };
 
 
-typedef vector<string> Strings;
+typedef list<string> Strings;
+typedef set<string> StringSet;
 
 
 /* The canonical system name, as returned by config.guess. */ 
 extern string thisSystem;
 
 
-/* The prefix of the Nix installation, and the environment variable
-   that can be used to override the default. */
-extern string nixHomeDir;
-extern string nixHomeDirEnvVar;
+/* Return an absolutized path, resolving paths relative to the
+   specified directory, or the current directory otherwise.  The path
+   is also canonicalised. */
+string absPath(string path, string dir = "");
+
+/* Canonicalise a path (as in realpath(3)). */
+string canonPath(const string & path);
+
+/* Return the directory part of the given path, i.e., everything
+   before the final `/'. */
+string dirOf(string path);
+
+/* Return the base name of the given path, i.e., everything following
+   the final `/'. */
+string baseNameOf(string path);
+
+/* Return true iff the given path exists. */
+bool pathExists(const string & path);
+
+/* Delete a path; i.e., in the case of a directory, it is deleted
+   recursively.  Don't use this at home, kids. */
+void deletePath(string path);
 
 
-string absPath(string filename, string dir = "");
-string dirOf(string s);
-string baseNameOf(string s);
+/* Messages. */
+
+typedef enum { 
+    lvlError, 
+    lvlTalkative,
+    lvlChatty,
+    lvlDebug,
+    lvlVomit
+} Verbosity;
+
+extern Verbosity verbosity; /* supress msgs > this */
+
+class Nest
+{
+private:
+    bool nest;
+public:
+    Nest(Verbosity level, const format & f);
+    ~Nest();
+};
+
+void msg(Verbosity level, const format & f);
+void debug(const format & f); /* short-hand for msg(lvlDebug, ...) */
+
+
+/* Wrappers arount read()/write() that read/write exactly the
+   requested number of bytes. */
+void readFull(int fd, unsigned char * buf, size_t count);
+void writeFull(int fd, const unsigned char * buf, size_t count);
 
 
 #endif /* !__UTIL_H */

substitute.mk

@@ -0,0 +1,8 @@
+%: %.in Makefile
+	sed \
+	 -e s^@prefix\@^$(prefix)^g \
+	 -e s^@bindir\@^$(bindir)^g \
+	 -e s^@sysconfdir\@^$(sysconfdir)^g \
+	 -e s^@localstatedir\@^$(localstatedir)^g \
+	 < $< > $@ || rm $@
+	chmod +x $@

sys/bootstrap

@@ -1,86 +0,0 @@
-#! /bin/sh
-
-. ./settings
-
-if ! ./mountloop; then
-    exit 1
-fi
-
-# Cleanup.
-rm -rf $target/dev
-rm -rf $target/proc
-
-# Create the basic directory structure.
-mkdir $target
-mkdir $target/dev
-mkdir $target/proc
-mkdir $target/pkg
-mkdir $target/pkg/sys
-mkdir $target/pkg/sys/bin
-mkdir $target/pkg/sys/var
-mkdir $target/mnt
-mkdir $target/mnt/host
-mkdir -m 1777 $target/tmp
-
-# Make package registrations.
-pkgdb=$target/pkg/sys/var/pkginfo
-
-# Copy some programs and its libraries.
-utils="/usr/bin/vi /bin/sh /bin/mount /bin/umount /bin/ls /bin/ln /bin/cp /bin/mv /bin/rm /bin/cat /bin/df /bin/pwd /usr/bin/ld /usr/bin/as /bin/sed /bin/chmod /bin/chown /usr/bin/expr /bin/mkdir /bin/rmdir /usr/bin/sort /usr/bin/uniq /bin/uname /usr/bin/grep /bin/sleep /bin/gzip /usr/bin/make /usr/bin/cmp /bin/date /usr/bin/tr /usr/bin/ar /usr/bin/ranlib /usr/bin/basename /usr/bin/less /usr/bin/md5sum /bin/tar ../src/nix"
-bootlib=/pkg/prog-bootstrap/lib
-bootbin=/pkg/prog-bootstrap/bin
-mkdir -p $target/$bootlib
-mkdir -p $target/$bootbin
-cp -p $utils $target/$bootbin
-libs=`ldd $utils | awk '{ print $3 }' | sort | uniq`
-echo $libs
-cp -p $libs $target/$bootlib
-for i in libc.so.6 libdl.so.2 libpthread.so.0 librt.so.1 libresolv.so.2 ld-linux.so.2; do rm $target/$bootlib/$i; done
-../src/nix -d $pkgdb regpkg 5703121fe19cbeeaee7edd659cf4a25b /pkg/prog-bootstrap
-
-mv $target/$bootbin/nix $target/pkg/sys/bin
-../src/nix -d $pkgdb regpkg 36bcbb801f5052739af8220c6ea51434 /pkg/sys
-
-# Copy the bootstrap gcc.
-echo Copying gcc...
-rsync -a ../bootstrap/gcc/inst/pkg $target
-../src/nix -d $pkgdb regpkg 02212b3dc4e50349376975367d433929 /pkg/gcc-bootstrap
-
-# Copy the bootstrap glibc.
-echo Copying glibc...
-glibcdir=/pkg/glibc-bootstrap
-rsync -a ../bootstrap/glibc/inst/pkg $target
-../src/nix -d $pkgdb regpkg c0ce03ee0bab298babbe7e3b6159d36c $glibcdir
-
-# Copy the bootstrap kernel header files.
-echo Copying kernel headers...
-kerneldir=/pkg/kernel-bootstrap
-rsync -a ../bootstrap/kernel/inst/pkg $target
-../src/nix -d $pkgdb regpkg 3dc8333a2c2b4d627b892755417acf89 $kerneldir
-
-# Compatibility.
-rm -rf $target/lib
-mkdir $target/lib
-ln -sf $glibcdir/lib/ld-linux.so.2 $target/lib/ld-linux.so.2
-
-rm -rf $target/bin
-mkdir $target/bin
-ln -sf $bootbin/sh $target/bin/sh
-
-# Build ld.so.cache.
-ldsoconf=$target/$glibcdir/etc/ld.so.conf
-echo $glibcdir/lib > $ldsoconf
-echo $bootlib >> $ldsoconf
-$target/$glibcdir/sbin/ldconfig -r $target
-
-# Source repository.
-rm -f $target/src
-ln -sf /mnt/host/`pwd`/../pkg $target/src
-
-# Copy boot script.
-cp -p ./start $target/pkg/sys/bin
-
-# Done.
-echo Done!
-umount $target
-rmdir $target

sys/makedisk

@@ -1,11 +0,0 @@
-#! /bin/sh
-
-. ./settings
-
-rm $image
-
-dd if=/dev/zero of=$image bs=1M count=1 seek=256
-
-/sbin/mke2fs -F -j $image
-/sbin/tune2fs -c 0 $image
-/sbin/tune2fs -i 0 $image

sys/mountloop

@@ -1,8 +0,0 @@
-#! /bin/sh
-
-. ./settings
-
-mkdir $target
-if ! mount -o loop -t ext3 $image $target; then
-    exit 1
-fi

sys/runsystem

@@ -1,5 +0,0 @@
-#! /bin/sh
-
-. ./settings
-
-linux ubd0=$image init=/pkg/sys/bin/start

sys/settings

@@ -1,2 +0,0 @@
-image=/var/tmp/nix.img
-target=./loop

sys/start

@@ -1,38 +0,0 @@
-#! /pkg/prog-bootstrap/bin/sh
-
-# This directory contains nix.
-export PATH=/pkg/sys/bin
-
-# Add in the utilities needed for booting.
-export PATH=$PATH:`nix getpkg 5703121fe19cbeeaee7edd659cf4a25b`/bin
-
-echo
-echo Starting up...
-
-echo Mounting file systems...
-mount -n -o remount,rw /dev/root /
-mount -n -t proc none /proc
-mount -n -t hostfs none /mnt/host 
-
-echo Registering available sources...
-( if cd /src; then
-    for i in *; do
-      nix reg $i
-    done
-  fi
-)
-
-export PATH=`nix getpkg coreutils-4.5.7`/bin:$PATH
-
-echo
-echo "=== starting interactive shell ==="
-
-sh
-
-echo
-echo Shutting down...
-
-umount /proc
-#sync
-mount -n -o remount,ro /dev/root /
-#sync