- Make `descriptorToPath` cross-platform (renamed from
`windows::handleToPath`). Uses `/proc/self/fd` on Linux and
`F_GETPATH` on macOS. Add `HAVE_F_GETPATH` meson check.
This is based on 7226a116a0, which was
removed in 479c356510, but is now
introduced more judiciously.
- Unix error messages in `readFull`, `writeFull`, `readLine` now include
file paths via `descriptorToPath`.
- Convert `std::filesystem::filesystem_error` to `SystemError`
Wrappers like `readLink`, `createDirs`, `DirectoryIterator`, etc. now
catch `std::filesystem::filesystem_error` and rethrow as `SystemError`
with the error code preserved. This ensures consistent exception types
throughout the codebase.
Call sites that previously caught `filesystem_error` and rethrew with
`throw;` now throw `SystemError(e.code(), ...)` instead.
Some call sites can stop catching `filesystem_error` at all,
because they only call the wrapped functions.
- Rework `SystemError` constructors to auto-append error message
The public `SystemError(std::error_code, ...)` constructor now
automatically appends `errorCode.message()` to the error message.
A protected constructor takes an explicit error message string for
subclasses.
`SysError` delegates to the protected constructor with `strerror(errNo)`.
`WinError` delegates with `renderError(lastError)` (now static).
This removes the need to manually append `e.code().message()` at call
sites when converting `filesystem_error` to `SystemError`.
- Use perfect forwarding (`Args &&...` with `std::forward`) consistently
in `BaseError`, `SystemError`, `SysError`, and `WinError` constructors.
Co-authored-by: Sergei Zimmerman <sergei@zimmerman.foo>
In 3df91bea62 I forgot that the header
might get included out-of-tree with -Wundef. Let's make this a public
config option for libutil as it can affect function bodies in headers.
Using nix::unreachable() in getInternalType() and type() turns
out to be quite expensive and prevents inlining. Also Value::type
got compiled to a jump table which has a high overhead from indirect
jumps. Using an explicit lookup table turns out to be more efficient.
This does mean that we lose out on nice diagnostics from nix::unreachable
calls, but this code is probably one of the hottests functions in the whole
evaluator, so I think the tradeoff is worth it. The nixUnreachableWhenHardened
boils down to nix::unreachable when UBSan is enabled so we still have good
coverage there.
`file-descriptor.{cc,hh}` was getting too big, split out
`file-system-at.{cc,hh}` for the FD-based file system stuff,
`file-descriptor.{cc,hh}` will only be for the fundamental primitives
that are file-system agnostic and work on almost all file types.
Review with `git show --color-moved` to see that this is indeed all
moving.
When ref::cast() fails, the error message was cryptic ("null pointer
cast to ref"). Now it throws a proper bad_ref_cast (a std::bad_cast
subclass) with a clear message showing the actual types involved:
ref<nix::Base> cannot be cast to ref<nix::Derived>
This also adds a demangle.hh utility.
ref<Derived> was already implicitly convertible to ref<Base>, but the
mechanism was unclear and error messages for rejected downcasts were
more cryptic than necessary. This change:
- Adds RefImplicitlyUpcastableTo concept to constrain the conversion
operator, making the intent explicit and improving error messages
- Documents .cast() and .dynamic_pointer_cast() as alternatives for
explicit downcasting
- Adds unit tests for covariance behavior
The old check rejected any relative path whose first character was a
dot, producing false negatives for valid descendants like `.ssh` or
`.config`. This commit changes the logic such that now it inspects the
first path component via `path::begin()`, only rejects `.` and `..`
rather than anything dot-prefixed. Fixes#15207.
libutil tests were crashing on Windows due to issues finding `environ`.
Replace process creation of `getEnv` with a new `getEnvOs` function that
uses native windows APIs.
Also convert a bunch of `RunOptions` fields to use `OsString` to better
reflect the underlying interfaces.
Co-authored-by: John Ericson <John.Ericson@Obsidian.Systems>
This is a fairly simple function, isolated from the rest of libmain
and could be useful if new programs are made that are not part of the
main nix-cli subproject.
Diagnosed by UBSan in hydra [1]:
SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /nix/store/m1k4nxs8r0fl0pjxqp5n37vxgms7gdlb-gcc-14.3.0/include/c++/14.3.0/bits/move.h:234:11 in
+(prefetch.sh:6) path=
++(prefetch.sh:6) onError
++(/build/source/tests/functional/common/functions.sh:241) set +x
prefetch.sh: test failed at:
main in prefetch.sh:6
[1]: https://hydra.nixos.org/build/321098757/nixlog/1
This improves the performance of parseNarListing, which is used by commands
like `nix nar ls` when the underlying source allows cheap seeks (like StringSource
or FdSource that does lseek).
For `nix nar ls` of a NAR for linux source tarball this cuts down the runtime almost
in half (from 300ms -> 175ms).
This is purely a fix to use CreateFileW in mingw builds. Also adds some
FIXMEs for suspicious symlink following on truncation that can probably
be tightened down without any problems (other than nix-channel), but for
now this is a no-op change other than consistently using O_CLOEXEC, which
is harmless.
The C++ rule of five suggests that when a custom destructor is needed
then several other functions are as well. The lack of those makes
certain operations challenging
We use a different fstat on posix and windows systems,
and not all fstat users were using the correct one.
Factor out fstat to make the change easier.
See also a13de50df3 for other stat
functions
- Extract destructor logic into named methods (`deletePath()`,
`unmount()`, and `remove()`) that can be called explicitly. These ones
will throw exceptions normally, unlike the destructor which must quash
them to avoid double-exceptions.
- Use `std::filesystem::path` in `AutoUnmount` (changed from `Path`)
- Remove `del` field from `AutoRemoveJail`, using `INVALID_JAIL`
sentinel value instead.
- Add move assignment operators implemented via friend `swap` functions
for all three RAII classes.
- Remove old `reset(...)` methods that took parameters. These were a bit
misleading --- do they cancel or immediately destroy? --- and doing it
explicitly with cancel and then assignment is not hard.
Co-authored-by: Sergei Zimmerman <sergei@zimmerman.foo>
Use wrappers to make error handling easier.
On Windows we are using proper 64-bit time and size info.
We still have the problem of no `lstat` on Windows, but this will be
dealt with in future PRs.
This means that `RestoreSink` can work in the TOCTOU-resilliant way on
Windows too. And it also bodes will for the upcoming OS source accessor
improvements.
A few misc little refactors around error handling and whatnot are done
along the way too. (No more attempt to support pre Windows Vista! lol.)
This cannot be realiably automatically tested until we have a newer
version of Wine, but it does build, so I am inclined to say we just try
it for now.
Use
```
git show --color-moved --patience --color-moved-ws=ignore-all-space
```
to review and see that this is mostly code motion.
Co-Authored-By: John Ericson <John.Ericson@Obsidian.Systems>
