From 6e4e20009b00dc7482c9220bddbbc90375ddc24a Mon Sep 17 00:00:00 2001
From: "rickg%netscape.com"
 <rickg%netscape.com@18797224-902f-48f8-a5cc-f745e15eee43>
Date: Sun, 14 Nov 1999 06:22:52 +0000
Subject: [PATCH] bug18337 and fixes for embedded nulls; r=harishd

git-svn-id: svn://10.0.0.236/trunk@53450 18797224-902f-48f8-a5cc-f745e15eee43
---
 mozilla/string/obsolete/nsStr.cpp           | 30 ++++++---
 mozilla/string/obsolete/nsStr.h             | 29 ++++++---
 mozilla/string/obsolete/nsString.cpp        | 68 +++++++++-----------
 mozilla/string/obsolete/nsString.h          |  5 +-
 mozilla/string/obsolete/nsString2.cpp       | 70 ++++++++++++---------
 mozilla/string/obsolete/nsString2.h         |  9 +--
 mozilla/xpcom/ds/bufferRoutines.h           | 53 ++++++++--------
 mozilla/xpcom/ds/nsCRT.cpp                  | 63 ++++++++++---------
 mozilla/xpcom/ds/nsStr.cpp                  | 30 ++++++---
 mozilla/xpcom/ds/nsStr.h                    | 29 ++++++---
 mozilla/xpcom/ds/nsString.cpp               | 68 +++++++++-----------
 mozilla/xpcom/ds/nsString.h                 |  5 +-
 mozilla/xpcom/ds/nsString2.cpp              | 70 ++++++++++++---------
 mozilla/xpcom/ds/nsString2.h                |  9 +--
 mozilla/xpcom/string/obsolete/nsStr.cpp     | 30 ++++++---
 mozilla/xpcom/string/obsolete/nsStr.h       | 29 ++++++---
 mozilla/xpcom/string/obsolete/nsString.cpp  | 68 +++++++++-----------
 mozilla/xpcom/string/obsolete/nsString.h    |  5 +-
 mozilla/xpcom/string/obsolete/nsString2.cpp | 70 ++++++++++++---------
 mozilla/xpcom/string/obsolete/nsString2.h   |  9 +--
 20 files changed, 420 insertions(+), 329 deletions(-)

diff --git a/mozilla/string/obsolete/nsStr.cpp b/mozilla/string/obsolete/nsStr.cpp
index 211105c4724..dc1a0379c37 100644
--- a/mozilla/string/obsolete/nsStr.cpp
+++ b/mozilla/string/obsolete/nsStr.cpp
@@ -43,6 +43,7 @@
 //static const char* kCallRFindChar = "For better performance, call RFindChar() for targets whose length==1.";
 
 static const PRUnichar gCommonEmptyBuffer[1] = {0};
+static nsresult gStringAcquiredMemory = NS_OK;
 
 /**
  * This method initializes all the members of the nsStr structure 
@@ -303,10 +304,15 @@ void nsStr::ChangeCase(nsStr& aDest,PRBool aToUpper) {
 }
 
 /**
- * 
- * @update	gess1/7/99
- * @param 
- * @return
+ * This method removes characters from the given set from this string.
+ * NOTE: aSet is a char*, and it's length is computed using strlen, which assumes null termination.
+ *
+ * @update	gess 11/7/99
+ * @param aDest
+ * @param aSet
+ * @param aEliminateLeading
+ * @param aEliminateTrailing
+ * @return nothing
  */
 void nsStr::Trim(nsStr& aDest,const char* aSet,PRBool aEliminateLeading,PRBool aEliminateTrailing){
 
@@ -622,12 +628,12 @@ PRBool nsStr::Alloc(nsStr& aDest,PRUint32 aCount) {
   PRUint32 theSize=(theNewCapacity<<aDest.mCharSize);
   aDest.mStr = (char*)nsAllocator::Alloc(theSize);
 
-  PRBool result=PR_FALSE;
   if(aDest.mStr) {
     aDest.mOwnsBuffer=1;
-    result=PR_TRUE;
+    gStringAcquiredMemory=PR_TRUE;
   }
-  return result;
+  else gStringAcquiredMemory=PR_FALSE;
+  return gStringAcquiredMemory;
 }
 
 PRBool nsStr::Free(nsStr& aDest){
@@ -657,6 +663,16 @@ PRBool nsStr::Realloc(nsStr& aDest,PRUint32 aCount){
   return result;
 }
 
+/**
+ * Retrieve last memory error
+ *
+ * @update  gess 10/11/99
+ * @return  memory error (usually returns NS_OK)
+ */
+PRBool nsStr::DidAcquireMemory(void) {
+  return gStringAcquiredMemory;
+}
+
 //----------------------------------------------------------------------------------------
 
 CBufDescriptor::CBufDescriptor(char* aString,PRBool aStackBased,PRUint32 aCapacity,PRInt32 aLength) { 
diff --git a/mozilla/string/obsolete/nsStr.h b/mozilla/string/obsolete/nsStr.h
index 7f5c6c88273..b44eeb01358 100644
--- a/mozilla/string/obsolete/nsStr.h
+++ b/mozilla/string/obsolete/nsStr.h
@@ -45,17 +45,26 @@
 /***********************************************************************
   ASSUMPTIONS:
 
-    1. nsStrings and nsAutoString are always null terminated. 
-    2. If you try to set a null char (via SetChar()) a new length is set
-    3. nsCStrings can be upsampled into nsString without data loss
-    4. Char searching is faster than string searching. Use char interfaces
+    1. nsStrings and nsAutoString are always null terminated. However,
+       since it maintains a length byte, you can store NULL's inside
+       the string. Just be careful passing such buffers to 3rd party
+       API's that assume that NULL always terminate the buffer.
+
+    2. nsCStrings can be upsampled into nsString without data loss
+
+    3. Char searching is faster than string searching. Use char interfaces
        if your needs will allow it.
-    5. It's easy to use the stack for nsAutostring buffer storage (fast too!).
+
+    4. It's easy to use the stack for nsAutostring buffer storage (fast too!).
        See the CBufDescriptor class in this file.
-    6. It's ONLY ok to provide non-null-terminated buffers to Append() and Insert()
-       provided you specify a 0<n value for the optional count argument.
-    7. Downsampling from nsString to nsCString is lossy -- avoid it if possible!
-    8. Calls to ToNewCString() and ToNewUnicode() should be matched with calls to Recycle().
+
+    5. If you don't provide the optional count argument to Append() and Insert(),
+       the method will assume that the given buffer is terminated by the first
+       NULL it encounters.
+
+    6. Downsampling from nsString to nsCString can be lossy -- avoid it if possible!
+
+    7. Calls to ToNewCString() and ToNewUnicode() should be matched with calls to Recycle().
 
  ***********************************************************************/
 
@@ -399,6 +408,8 @@ struct NS_COM nsStr {
   static PRInt32 RFindChar(const nsStr& aDest,PRUnichar aChar, PRBool aIgnoreCase,PRInt32 anOffset);
   static PRInt32 RFindCharInSet(const nsStr& aDest,const nsStr& aSet,PRBool aIgnoreCase,PRInt32 anOffset);
 
+  static PRBool   DidAcquireMemory(void);
+
 
   PRUint32        mLength;
   PRUint32        mCapacity;
diff --git a/mozilla/string/obsolete/nsString.cpp b/mozilla/string/obsolete/nsString.cpp
index 43af1d45da6..cef4a597837 100644
--- a/mozilla/string/obsolete/nsString.cpp
+++ b/mozilla/string/obsolete/nsString.cpp
@@ -87,26 +87,7 @@ nsCString::nsCString(const char* aCString,PRInt32 aLength) {
  */
 nsCString::nsCString(const PRUnichar* aString,PRInt32 aLength)  {  
   nsStr::Initialize(*this,eOneByte);
-
-  if(aString && aLength){
-    nsStr temp;
-    Initialize(temp,eTwoByte);
-    temp.mUStr=(PRUnichar*)aString;
-
-    if(0<aLength) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
-      temp.mLength=aLength;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<(PRInt32)mLength)) {
-        aLength=temp.mLength=pos;
-      }
-    }
-    else aLength=temp.mLength=nsCRT::strlen(aString);
-
-    if(0<aLength)
-      nsStr::Append(*this,temp,0,aLength);
-  }
+  Assign(aString,aLength);
 }
 
 /**
@@ -248,12 +229,12 @@ PRBool nsCString::SetCharAt(PRUnichar aChar,PRUint32 anIndex){
   PRBool result=PR_FALSE;
   if(anIndex<mLength){
     mStr[anIndex]=(char)aChar;
-// SOON!   if(0==aChar) mLength=anIndex;
     result=PR_TRUE;
   }
   return result;
 }
 
+
 /*********************************************************
   append (operator+) METHODS....
  *********************************************************/
@@ -803,19 +784,21 @@ nsCString& nsCString::Assign(const char* aCString,PRInt32 aCount) {
 nsCString& nsCString::Assign(const PRUnichar* aString,PRInt32 aCount) {
   nsStr::Truncate(*this,0);
 
-  if(aString){
+  if(aString && aCount){
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in Assign(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
 
@@ -825,6 +808,7 @@ nsCString& nsCString::Assign(const PRUnichar* aString,PRInt32 aCount) {
   return *this;
 }
 
+
 /**
  * assign given unichar to this string
  * @update  gess 01/04/99
@@ -913,13 +897,15 @@ nsCString& nsCString::Append(const char* aCString,PRInt32 aCount) {
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Append(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
@@ -1099,13 +1085,15 @@ nsCString& nsCString::Insert(const char* aCString,PRUint32 anOffset,PRInt32 aCou
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
diff --git a/mozilla/string/obsolete/nsString.h b/mozilla/string/obsolete/nsString.h
index 27a0421e649..9c25db78800 100644
--- a/mozilla/string/obsolete/nsString.h
+++ b/mozilla/string/obsolete/nsString.h
@@ -398,8 +398,9 @@ public:
    */
   nsCString& operator+=(const nsCString& aString){return Append(aString,aString.mLength);}
   nsCString& operator+=(const char* aCString) {return Append(aCString);}
-  nsCString& operator+=(PRUnichar aChar){return Append(aChar);}
-  nsCString& operator+=(char aChar){return Append(aChar);}
+  nsCString& operator+=(const PRUnichar aChar){return Append(aChar);}
+  nsCString& operator+=(const char aChar){return Append(aChar);}
+  nsCString& operator+=(const int anInt){return Append(anInt,10);}
 
   /*
    *  Appends n characters from given string to this,
diff --git a/mozilla/string/obsolete/nsString2.cpp b/mozilla/string/obsolete/nsString2.cpp
index 83cbc8120f5..27321798c3b 100644
--- a/mozilla/string/obsolete/nsString2.cpp
+++ b/mozilla/string/obsolete/nsString2.cpp
@@ -72,9 +72,9 @@ nsString::nsString() {
  * @param   aCString is a ptr to a 1-byte cstr
  * @param   aLength tells us how many chars to copy from given CString
  */
-nsString::nsString(const char* aCString){  
+nsString::nsString(const char* aCString,PRInt32 aCount){  
   nsStr::Initialize(*this,eTwoByte);
-  Assign(aCString);
+  Assign(aCString,aCount);
 }
 
 /**
@@ -83,9 +83,9 @@ nsString::nsString(const char* aCString){
  * @param   aString is a ptr to a unichar string
  * @param   aLength tells us how many chars to copy from given aString
  */
-nsString::nsString(const PRUnichar* aString) {  
+nsString::nsString(const PRUnichar* aString,PRInt32 aCount) {  
   nsStr::Initialize(*this,eTwoByte);
-  Assign(aString);
+  Assign(aString,aCount);
 }
 
 /**
@@ -270,6 +270,7 @@ PRBool nsString::SetCharAt(PRUnichar aChar,PRUint32 anIndex){
   return result;
 }
 
+
 /*********************************************************
   append (operator+) METHODS....
  *********************************************************/
@@ -1037,13 +1038,15 @@ nsString& nsString::Append(const char* aCString,PRInt32 aCount) {
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in append(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
       
@@ -1067,13 +1070,15 @@ nsString& nsString::Append(const PRUnichar* aString,PRInt32 aCount) {
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in append(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
       
@@ -1255,13 +1260,15 @@ nsString& nsString::Insert(const char* aCString,PRUint32 anOffset,PRInt32 aCount
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
@@ -1288,13 +1295,15 @@ nsString& nsString::Insert(const PRUnichar* aString,PRUint32 anOffset,PRInt32 aC
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
 
@@ -1699,7 +1708,9 @@ PRInt32 nsString::Compare(const char *aCString,PRBool aIgnoreCase,PRInt32 aCount
   if(aCString) {
     nsStr temp;
     nsStr::Initialize(temp,eOneByte);
-    temp.mLength=nsCRT::strlen(aCString);
+
+    temp.mLength= (0<aCount) ? aCount : nsCRT::strlen(aCString);
+
     temp.mStr=(char*)aCString;
     return nsStr::Compare(*this,temp,aCount,aIgnoreCase);
   }
@@ -1792,6 +1803,7 @@ PRBool nsString::EqualsIgnoreCase(const PRUnichar* s1, const PRUnichar* s2) cons
   return Equals(s1,s2,PR_TRUE);
 }
 
+
 /**
  * Compare this to given string; note that we compare full strings here.
  * 
diff --git a/mozilla/string/obsolete/nsString2.h b/mozilla/string/obsolete/nsString2.h
index 9cb0e8fd986..21bcb03461c 100644
--- a/mozilla/string/obsolete/nsString2.h
+++ b/mozilla/string/obsolete/nsString2.h
@@ -69,13 +69,13 @@ public:
    * This constructor accepts an isolatin string
    * @param   aCString is a ptr to a 1-byte cstr
    */
-  nsString(const char* aCString);
+  nsString(const char* aCString,PRInt32 aCount=-1);
 
   /**
    * This constructor accepts a unichar string
    * @param   aCString is a ptr to a 2-byte cstr
    */
-  nsString(const PRUnichar* aString);
+  nsString(const PRUnichar* aString,PRInt32 aCount=-1);
 
   /**
    * This is a copy constructor that accepts an nsStr
@@ -442,9 +442,10 @@ public:
   nsString& operator+=(const nsStr& aString){return Append(aString,aString.mLength);}
   nsString& operator+=(const nsString& aString){return Append(aString,aString.mLength);}
   nsString& operator+=(const char* aCString) {return Append(aCString);}
-  //nsString& operator+=(char aChar){return Append(aChar);}
+  nsString& operator+=(const char aChar) {return Append(PRUnichar(unsigned char(aChar)));}
   nsString& operator+=(const PRUnichar* aUCString) {return Append(aUCString);}
-  nsString& operator+=(PRUnichar aChar){return Append(aChar);}
+  nsString& operator+=(const PRUnichar aChar){return Append(aChar);}
+  nsString& operator+=(const int anInt){return Append(anInt,10);}
 
   /*
    *  Appends n characters from given string to this,
diff --git a/mozilla/xpcom/ds/bufferRoutines.h b/mozilla/xpcom/ds/bufferRoutines.h
index d734d103798..c908fc239c1 100644
--- a/mozilla/xpcom/ds/bufferRoutines.h
+++ b/mozilla/xpcom/ds/bufferRoutines.h
@@ -400,7 +400,7 @@ PRInt32 Compare1To1(const char* aStr1,const char* aStr2,PRUint32 aCount,PRBool a
   PRInt32 result=0;
   if(aIgnoreCase)
     result=nsCRT::strncasecmp(aStr1,aStr2,aCount);
-  else result=strncmp(aStr1,aStr2,aCount);
+  else result=memcmp(aStr1,aStr2,aCount);
   return result;
 }
 
@@ -618,17 +618,16 @@ CaseConverters gCaseConverters[]={&ConvertCase1,&ConvertCase2};
  */
 PRInt32 CompressChars1(char* aString,PRUint32 aLength,const char* aSet){ 
 
-  typedef char  chartype;
-  chartype*  from = aString;
-  chartype*  end =  aString + aLength-1;
-  chartype*  to = from;
+  char*  from = aString;
+  char*  end =  aString + aLength-1;
+  char*  to = from;
 
     //this code converts /n, /t, /r into normal space ' ';
     //it also compresses runs of whitespace down to a single char...
   if(aSet && aString && (0 < aLength)){
     PRUint32 aSetLen=strlen(aSet);
     while (from <= end) {
-      chartype theChar = *from++;
+      char theChar = *from++;
       if(kNotFound!=FindChar1(aSet,aSetLen,0,theChar,PR_FALSE)){
         *to++=theChar;
         while (from <= end) {
@@ -644,7 +643,7 @@ PRInt32 CompressChars1(char* aString,PRUint32 aLength,const char* aSet){
     }
     *to = 0;
   }
-  return to - (chartype*)aString;
+  return to - (char*)aString;
 }
 
 
@@ -661,18 +660,17 @@ PRInt32 CompressChars1(char* aString,PRUint32 aLength,const char* aSet){
  */
 PRInt32 CompressChars2(char* aString,PRUint32 aLength,const char* aSet){ 
 
-  typedef PRUnichar  chartype;
-  chartype*  from = (chartype*)aString;
-  chartype*  end =  from + aLength-1;
-  chartype*  to = from;
+  PRUnichar*  from = (PRUnichar*)aString;
+  PRUnichar*  end =  from + aLength-1;
+  PRUnichar*  to = from;
 
     //this code converts /n, /t, /r into normal space ' ';
     //it also compresses runs of whitespace down to a single char...
   if(aSet && aString && (0 < aLength)){
     PRUint32 aSetLen=strlen(aSet);
     while (from <= end) {
-      chartype theChar = *from++;
-      if(kNotFound!=FindChar1(aSet,aSetLen,0,theChar,PR_FALSE)){
+      PRUnichar theChar = *from++;
+      if((255<theChar) || (kNotFound!=FindChar1(aSet,aSetLen,0,theChar,PR_FALSE))){
         *to++=theChar;
         while (from <= end) {
           theChar = *from++;
@@ -687,7 +685,7 @@ PRInt32 CompressChars2(char* aString,PRUint32 aLength,const char* aSet){
     }
     *to = 0;
   }
-  return to - (chartype*)aString;
+  return to - (PRUnichar*)aString;
 }
 
 typedef PRInt32 (*CompressChars)(char* aString,PRUint32 aCount,const char* aSet);
@@ -706,22 +704,21 @@ CompressChars gCompressChars[]={&CompressChars1,&CompressChars2};
  */
 PRInt32 StripChars1(char* aString,PRUint32 aLength,const char* aSet){ 
 
-  typedef char  chartype;
-  chartype*  to   = aString;
-  chartype*  from = aString-1;
-  chartype*  end  = aString + aLength;
+  char*  to   = aString;
+  char*  from = aString-1;
+  char*  end  = aString + aLength;
 
   if(aSet && aString && (0 < aLength)){
     PRUint32 aSetLen=strlen(aSet);
     while (++from < end) {
-      chartype theChar = *from;
+      char theChar = *from;
       if(kNotFound==FindChar1(aSet,aSetLen,0,theChar,PR_FALSE)){
         *to++ = theChar;
       }
     }
     *to = 0;
   }
-  return to - (chartype*)aString;
+  return to - (char*)aString;
 }
 
 
@@ -738,22 +735,24 @@ PRInt32 StripChars1(char* aString,PRUint32 aLength,const char* aSet){
  */
 PRInt32 StripChars2(char* aString,PRUint32 aLength,const char* aSet){ 
 
-  typedef PRUnichar  chartype;
-  chartype*  to   = (chartype*)aString;
-  chartype*  from = (chartype*)aString-1;
-  chartype*  end  = to + aLength;
+  PRUnichar*  to   = (PRUnichar*)aString;
+  PRUnichar*  from = (PRUnichar*)aString-1;
+  PRUnichar*  end  = to + aLength;
 
   if(aSet && aString && (0 < aLength)){
     PRUint32 aSetLen=strlen(aSet);
     while (++from < end) {
-      chartype theChar = *from;
-      if(kNotFound==FindChar1(aSet,aSetLen,0,theChar,PR_FALSE)){
+      PRUnichar theChar = *from;
+      //Note the test for ascii range below. If you have a real unicode char, 
+      //and you're searching for chars in the (given) ascii string, there's no
+      //point in doing the real search since it's out of the ascii range.
+      if((255<theChar) || (kNotFound==FindChar1(aSet,aSetLen,0,theChar,PR_FALSE))){
         *to++ = theChar;
       }
     }
     *to = 0;
   }
-  return to - (chartype*)aString;
+  return to - (PRUnichar*)aString;
 }
 
 typedef PRInt32 (*StripChars)(char* aString,PRUint32 aCount,const char* aSet);
diff --git a/mozilla/xpcom/ds/nsCRT.cpp b/mozilla/xpcom/ds/nsCRT.cpp
index 1c61de07afd..2ee9a21fdbd 100644
--- a/mozilla/xpcom/ds/nsCRT.cpp
+++ b/mozilla/xpcom/ds/nsCRT.cpp
@@ -236,12 +236,13 @@ PRUint32 nsCRT::strlen(const PRUnichar* s)
 /**
  * Compare unichar string ptrs, stopping at the 1st null 
  * NOTE: If both are null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We terminate the search upon encountering a NULL
+ *
+ * @update  gess 11/10/99
  * @param   s1 and s2 both point to unichar strings
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strcmp(const PRUnichar* s1, const PRUnichar* s2)
-{
+PRInt32 nsCRT::strcmp(const PRUnichar* s1, const PRUnichar* s2) {
   if(s1 && s2) {
     for (;;) {
       PRUnichar c1 = *s1++;
@@ -259,12 +260,13 @@ PRInt32 nsCRT::strcmp(const PRUnichar* s1, const PRUnichar* s2)
 /**
  * Compare unichar string ptrs, stopping at the 1st null or nth char.
  * NOTE: If either is null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We DO NOT terminate the search upon encountering NULL's before N
+ *
+ * @update  gess 11/10/99
  * @param   s1 and s2 both point to unichar strings
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strncmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n)
-{
+PRInt32 nsCRT::strncmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n) {
   if(s1 && s2) { 
     if(n != 0) {
       do {
@@ -274,23 +276,22 @@ PRInt32 nsCRT::strncmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n)
           if (c1 < c2) return -1;
           return 1;
         }
-        if ((0==c1) || (0==c2)) break;
       } while (--n != 0);
     }
   }
   return 0;
 }
 
-
 /**
  * Compare unichar string ptrs without regard to case
  * NOTE: If both are null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We terminate the search upon encountering NULL
+ *
+ * @update  gess 11/10/99
  * @param   s1 and s2 both point to unichar strings
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strcasecmp(const PRUnichar* s1, const PRUnichar* s2)
-{
+PRInt32 nsCRT::strcasecmp(const PRUnichar* s1, const PRUnichar* s2) {
   if(s1 && s2) {
     for (;;) {
       PRUnichar c1 = *s1++;
@@ -313,12 +314,13 @@ PRInt32 nsCRT::strcasecmp(const PRUnichar* s1, const PRUnichar* s2)
  * Compare unichar string ptrs, stopping at the 1st null or nth char;
  * also ignoring the case of characters.
  * NOTE: If both are null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We DO NOT terminate the search upon encountering NULL's before N
+ *
+ * @update  gess 11/10/99
  * @param   s1 and s2 both point to unichar strings
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n)
-{
+PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n) {
   if(s1 && s2) {
     if(n != 0){
       do {
@@ -332,7 +334,6 @@ PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n)
             return 1;
           }
         }
-        if ((0==c1) || (0==c2)) break;
       } while (--n != 0);
     }
   }
@@ -343,13 +344,14 @@ PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const PRUnichar* s2, PRUint32 n)
 /**
  * Compare a unichar string ptr to cstring.
  * NOTE: If both are null, we return 0.
+ * NOTE: We terminate the search upon encountering NULL's
+ *
  * @update  gess7/30/98
  * @param   s1 points to unichar string
  * @param   s2 points to cstring
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strcmp(const PRUnichar* s1, const char* s2)
-{
+PRInt32 nsCRT::strcmp(const PRUnichar* s1, const char* s2) {
   if(s1 && s2) {
     for (;;) {
       PRUnichar c1 = *s1++;
@@ -368,15 +370,16 @@ PRInt32 nsCRT::strcmp(const PRUnichar* s1, const char* s2)
 /**
  * Compare a unichar string ptr to cstring, up to N chars.
  * NOTE: If both are null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We DO NOT terminate the search upon encountering NULL's before N
+ *
+ * @update  gess 11/10/99
  * @param   s1 points to unichar string
  * @param   s2 points to cstring
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strncmp(const PRUnichar* s1, const char* s2, PRUint32 n)
-{
+PRInt32 nsCRT::strncmp(const PRUnichar* s1, const char* s2, PRUint32 n) {
   if(s1 && s2) {
-    if(n != 0){
+    if(0<n){
       do {
         PRUnichar c1 = *s1++;
         PRUnichar c2 = kIsoLatin1ToUCS2[*(const unsigned char*)s2++];
@@ -384,23 +387,24 @@ PRInt32 nsCRT::strncmp(const PRUnichar* s1, const char* s2, PRUint32 n)
           if (c1 < c2) return -1;
           return 1;
         }
-        if ((0==c1) || (0==c2)) break;
       } while (--n != 0);
     }
   }
   return 0;
 }
 
+
 /**
  * Compare a unichar string ptr to cstring without regard to case
  * NOTE: If both are null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We terminate the search upon encountering NULL's 
+ *
+ * @update  gess 11/10/99
  * @param   s1 points to unichar string
  * @param   s2 points to cstring
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strcasecmp(const PRUnichar* s1, const char* s2)
-{
+PRInt32 nsCRT::strcasecmp(const PRUnichar* s1, const char* s2) {
   if(s1 && s2) {
     for (;;) {
       PRUnichar c1 = *s1++;
@@ -422,13 +426,14 @@ PRInt32 nsCRT::strcasecmp(const PRUnichar* s1, const char* s2)
 /**
  * Caseless compare up to N chars between unichar string ptr to cstring.
  * NOTE: If both are null, we return 0.
- * @update  gess7/30/98
+ * NOTE: We DO NOT terminate the search upon encountering NULL's before N
+ *
+ * @update  gess 11/10/99
  * @param   s1 points to unichar string
  * @param   s2 points to cstring
  * @return  0 if they match, -1 if s1<s2; 1 if s1>s2
  */
-PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const char* s2, PRUint32 n)
-{
+PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const char* s2, PRUint32 n) {
   if(s1 && s2){
     if(n != 0){
       do {
@@ -442,13 +447,13 @@ PRInt32 nsCRT::strncasecmp(const PRUnichar* s1, const char* s2, PRUint32 n)
             return 1;
           }
         }
-        if (c1 == 0) break;
       } while (--n != 0);
     }
   }
   return 0;
 }
 
+
 PRUnichar* nsCRT::strdup(const PRUnichar* str)
 {
   PRUint32 len = nsCRT::strlen(str) + 1; // add one for null
diff --git a/mozilla/xpcom/ds/nsStr.cpp b/mozilla/xpcom/ds/nsStr.cpp
index 211105c4724..dc1a0379c37 100644
--- a/mozilla/xpcom/ds/nsStr.cpp
+++ b/mozilla/xpcom/ds/nsStr.cpp
@@ -43,6 +43,7 @@
 //static const char* kCallRFindChar = "For better performance, call RFindChar() for targets whose length==1.";
 
 static const PRUnichar gCommonEmptyBuffer[1] = {0};
+static nsresult gStringAcquiredMemory = NS_OK;
 
 /**
  * This method initializes all the members of the nsStr structure 
@@ -303,10 +304,15 @@ void nsStr::ChangeCase(nsStr& aDest,PRBool aToUpper) {
 }
 
 /**
- * 
- * @update	gess1/7/99
- * @param 
- * @return
+ * This method removes characters from the given set from this string.
+ * NOTE: aSet is a char*, and it's length is computed using strlen, which assumes null termination.
+ *
+ * @update	gess 11/7/99
+ * @param aDest
+ * @param aSet
+ * @param aEliminateLeading
+ * @param aEliminateTrailing
+ * @return nothing
  */
 void nsStr::Trim(nsStr& aDest,const char* aSet,PRBool aEliminateLeading,PRBool aEliminateTrailing){
 
@@ -622,12 +628,12 @@ PRBool nsStr::Alloc(nsStr& aDest,PRUint32 aCount) {
   PRUint32 theSize=(theNewCapacity<<aDest.mCharSize);
   aDest.mStr = (char*)nsAllocator::Alloc(theSize);
 
-  PRBool result=PR_FALSE;
   if(aDest.mStr) {
     aDest.mOwnsBuffer=1;
-    result=PR_TRUE;
+    gStringAcquiredMemory=PR_TRUE;
   }
-  return result;
+  else gStringAcquiredMemory=PR_FALSE;
+  return gStringAcquiredMemory;
 }
 
 PRBool nsStr::Free(nsStr& aDest){
@@ -657,6 +663,16 @@ PRBool nsStr::Realloc(nsStr& aDest,PRUint32 aCount){
   return result;
 }
 
+/**
+ * Retrieve last memory error
+ *
+ * @update  gess 10/11/99
+ * @return  memory error (usually returns NS_OK)
+ */
+PRBool nsStr::DidAcquireMemory(void) {
+  return gStringAcquiredMemory;
+}
+
 //----------------------------------------------------------------------------------------
 
 CBufDescriptor::CBufDescriptor(char* aString,PRBool aStackBased,PRUint32 aCapacity,PRInt32 aLength) { 
diff --git a/mozilla/xpcom/ds/nsStr.h b/mozilla/xpcom/ds/nsStr.h
index 7f5c6c88273..b44eeb01358 100644
--- a/mozilla/xpcom/ds/nsStr.h
+++ b/mozilla/xpcom/ds/nsStr.h
@@ -45,17 +45,26 @@
 /***********************************************************************
   ASSUMPTIONS:
 
-    1. nsStrings and nsAutoString are always null terminated. 
-    2. If you try to set a null char (via SetChar()) a new length is set
-    3. nsCStrings can be upsampled into nsString without data loss
-    4. Char searching is faster than string searching. Use char interfaces
+    1. nsStrings and nsAutoString are always null terminated. However,
+       since it maintains a length byte, you can store NULL's inside
+       the string. Just be careful passing such buffers to 3rd party
+       API's that assume that NULL always terminate the buffer.
+
+    2. nsCStrings can be upsampled into nsString without data loss
+
+    3. Char searching is faster than string searching. Use char interfaces
        if your needs will allow it.
-    5. It's easy to use the stack for nsAutostring buffer storage (fast too!).
+
+    4. It's easy to use the stack for nsAutostring buffer storage (fast too!).
        See the CBufDescriptor class in this file.
-    6. It's ONLY ok to provide non-null-terminated buffers to Append() and Insert()
-       provided you specify a 0<n value for the optional count argument.
-    7. Downsampling from nsString to nsCString is lossy -- avoid it if possible!
-    8. Calls to ToNewCString() and ToNewUnicode() should be matched with calls to Recycle().
+
+    5. If you don't provide the optional count argument to Append() and Insert(),
+       the method will assume that the given buffer is terminated by the first
+       NULL it encounters.
+
+    6. Downsampling from nsString to nsCString can be lossy -- avoid it if possible!
+
+    7. Calls to ToNewCString() and ToNewUnicode() should be matched with calls to Recycle().
 
  ***********************************************************************/
 
@@ -399,6 +408,8 @@ struct NS_COM nsStr {
   static PRInt32 RFindChar(const nsStr& aDest,PRUnichar aChar, PRBool aIgnoreCase,PRInt32 anOffset);
   static PRInt32 RFindCharInSet(const nsStr& aDest,const nsStr& aSet,PRBool aIgnoreCase,PRInt32 anOffset);
 
+  static PRBool   DidAcquireMemory(void);
+
 
   PRUint32        mLength;
   PRUint32        mCapacity;
diff --git a/mozilla/xpcom/ds/nsString.cpp b/mozilla/xpcom/ds/nsString.cpp
index 43af1d45da6..cef4a597837 100644
--- a/mozilla/xpcom/ds/nsString.cpp
+++ b/mozilla/xpcom/ds/nsString.cpp
@@ -87,26 +87,7 @@ nsCString::nsCString(const char* aCString,PRInt32 aLength) {
  */
 nsCString::nsCString(const PRUnichar* aString,PRInt32 aLength)  {  
   nsStr::Initialize(*this,eOneByte);
-
-  if(aString && aLength){
-    nsStr temp;
-    Initialize(temp,eTwoByte);
-    temp.mUStr=(PRUnichar*)aString;
-
-    if(0<aLength) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
-      temp.mLength=aLength;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<(PRInt32)mLength)) {
-        aLength=temp.mLength=pos;
-      }
-    }
-    else aLength=temp.mLength=nsCRT::strlen(aString);
-
-    if(0<aLength)
-      nsStr::Append(*this,temp,0,aLength);
-  }
+  Assign(aString,aLength);
 }
 
 /**
@@ -248,12 +229,12 @@ PRBool nsCString::SetCharAt(PRUnichar aChar,PRUint32 anIndex){
   PRBool result=PR_FALSE;
   if(anIndex<mLength){
     mStr[anIndex]=(char)aChar;
-// SOON!   if(0==aChar) mLength=anIndex;
     result=PR_TRUE;
   }
   return result;
 }
 
+
 /*********************************************************
   append (operator+) METHODS....
  *********************************************************/
@@ -803,19 +784,21 @@ nsCString& nsCString::Assign(const char* aCString,PRInt32 aCount) {
 nsCString& nsCString::Assign(const PRUnichar* aString,PRInt32 aCount) {
   nsStr::Truncate(*this,0);
 
-  if(aString){
+  if(aString && aCount){
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in Assign(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
 
@@ -825,6 +808,7 @@ nsCString& nsCString::Assign(const PRUnichar* aString,PRInt32 aCount) {
   return *this;
 }
 
+
 /**
  * assign given unichar to this string
  * @update  gess 01/04/99
@@ -913,13 +897,15 @@ nsCString& nsCString::Append(const char* aCString,PRInt32 aCount) {
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Append(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
@@ -1099,13 +1085,15 @@ nsCString& nsCString::Insert(const char* aCString,PRUint32 anOffset,PRInt32 aCou
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
diff --git a/mozilla/xpcom/ds/nsString.h b/mozilla/xpcom/ds/nsString.h
index 27a0421e649..9c25db78800 100644
--- a/mozilla/xpcom/ds/nsString.h
+++ b/mozilla/xpcom/ds/nsString.h
@@ -398,8 +398,9 @@ public:
    */
   nsCString& operator+=(const nsCString& aString){return Append(aString,aString.mLength);}
   nsCString& operator+=(const char* aCString) {return Append(aCString);}
-  nsCString& operator+=(PRUnichar aChar){return Append(aChar);}
-  nsCString& operator+=(char aChar){return Append(aChar);}
+  nsCString& operator+=(const PRUnichar aChar){return Append(aChar);}
+  nsCString& operator+=(const char aChar){return Append(aChar);}
+  nsCString& operator+=(const int anInt){return Append(anInt,10);}
 
   /*
    *  Appends n characters from given string to this,
diff --git a/mozilla/xpcom/ds/nsString2.cpp b/mozilla/xpcom/ds/nsString2.cpp
index 83cbc8120f5..27321798c3b 100644
--- a/mozilla/xpcom/ds/nsString2.cpp
+++ b/mozilla/xpcom/ds/nsString2.cpp
@@ -72,9 +72,9 @@ nsString::nsString() {
  * @param   aCString is a ptr to a 1-byte cstr
  * @param   aLength tells us how many chars to copy from given CString
  */
-nsString::nsString(const char* aCString){  
+nsString::nsString(const char* aCString,PRInt32 aCount){  
   nsStr::Initialize(*this,eTwoByte);
-  Assign(aCString);
+  Assign(aCString,aCount);
 }
 
 /**
@@ -83,9 +83,9 @@ nsString::nsString(const char* aCString){
  * @param   aString is a ptr to a unichar string
  * @param   aLength tells us how many chars to copy from given aString
  */
-nsString::nsString(const PRUnichar* aString) {  
+nsString::nsString(const PRUnichar* aString,PRInt32 aCount) {  
   nsStr::Initialize(*this,eTwoByte);
-  Assign(aString);
+  Assign(aString,aCount);
 }
 
 /**
@@ -270,6 +270,7 @@ PRBool nsString::SetCharAt(PRUnichar aChar,PRUint32 anIndex){
   return result;
 }
 
+
 /*********************************************************
   append (operator+) METHODS....
  *********************************************************/
@@ -1037,13 +1038,15 @@ nsString& nsString::Append(const char* aCString,PRInt32 aCount) {
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in append(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
       
@@ -1067,13 +1070,15 @@ nsString& nsString::Append(const PRUnichar* aString,PRInt32 aCount) {
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in append(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
       
@@ -1255,13 +1260,15 @@ nsString& nsString::Insert(const char* aCString,PRUint32 anOffset,PRInt32 aCount
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
@@ -1288,13 +1295,15 @@ nsString& nsString::Insert(const PRUnichar* aString,PRUint32 anOffset,PRInt32 aC
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
 
@@ -1699,7 +1708,9 @@ PRInt32 nsString::Compare(const char *aCString,PRBool aIgnoreCase,PRInt32 aCount
   if(aCString) {
     nsStr temp;
     nsStr::Initialize(temp,eOneByte);
-    temp.mLength=nsCRT::strlen(aCString);
+
+    temp.mLength= (0<aCount) ? aCount : nsCRT::strlen(aCString);
+
     temp.mStr=(char*)aCString;
     return nsStr::Compare(*this,temp,aCount,aIgnoreCase);
   }
@@ -1792,6 +1803,7 @@ PRBool nsString::EqualsIgnoreCase(const PRUnichar* s1, const PRUnichar* s2) cons
   return Equals(s1,s2,PR_TRUE);
 }
 
+
 /**
  * Compare this to given string; note that we compare full strings here.
  * 
diff --git a/mozilla/xpcom/ds/nsString2.h b/mozilla/xpcom/ds/nsString2.h
index 9cb0e8fd986..21bcb03461c 100644
--- a/mozilla/xpcom/ds/nsString2.h
+++ b/mozilla/xpcom/ds/nsString2.h
@@ -69,13 +69,13 @@ public:
    * This constructor accepts an isolatin string
    * @param   aCString is a ptr to a 1-byte cstr
    */
-  nsString(const char* aCString);
+  nsString(const char* aCString,PRInt32 aCount=-1);
 
   /**
    * This constructor accepts a unichar string
    * @param   aCString is a ptr to a 2-byte cstr
    */
-  nsString(const PRUnichar* aString);
+  nsString(const PRUnichar* aString,PRInt32 aCount=-1);
 
   /**
    * This is a copy constructor that accepts an nsStr
@@ -442,9 +442,10 @@ public:
   nsString& operator+=(const nsStr& aString){return Append(aString,aString.mLength);}
   nsString& operator+=(const nsString& aString){return Append(aString,aString.mLength);}
   nsString& operator+=(const char* aCString) {return Append(aCString);}
-  //nsString& operator+=(char aChar){return Append(aChar);}
+  nsString& operator+=(const char aChar) {return Append(PRUnichar(unsigned char(aChar)));}
   nsString& operator+=(const PRUnichar* aUCString) {return Append(aUCString);}
-  nsString& operator+=(PRUnichar aChar){return Append(aChar);}
+  nsString& operator+=(const PRUnichar aChar){return Append(aChar);}
+  nsString& operator+=(const int anInt){return Append(anInt,10);}
 
   /*
    *  Appends n characters from given string to this,
diff --git a/mozilla/xpcom/string/obsolete/nsStr.cpp b/mozilla/xpcom/string/obsolete/nsStr.cpp
index 211105c4724..dc1a0379c37 100644
--- a/mozilla/xpcom/string/obsolete/nsStr.cpp
+++ b/mozilla/xpcom/string/obsolete/nsStr.cpp
@@ -43,6 +43,7 @@
 //static const char* kCallRFindChar = "For better performance, call RFindChar() for targets whose length==1.";
 
 static const PRUnichar gCommonEmptyBuffer[1] = {0};
+static nsresult gStringAcquiredMemory = NS_OK;
 
 /**
  * This method initializes all the members of the nsStr structure 
@@ -303,10 +304,15 @@ void nsStr::ChangeCase(nsStr& aDest,PRBool aToUpper) {
 }
 
 /**
- * 
- * @update	gess1/7/99
- * @param 
- * @return
+ * This method removes characters from the given set from this string.
+ * NOTE: aSet is a char*, and it's length is computed using strlen, which assumes null termination.
+ *
+ * @update	gess 11/7/99
+ * @param aDest
+ * @param aSet
+ * @param aEliminateLeading
+ * @param aEliminateTrailing
+ * @return nothing
  */
 void nsStr::Trim(nsStr& aDest,const char* aSet,PRBool aEliminateLeading,PRBool aEliminateTrailing){
 
@@ -622,12 +628,12 @@ PRBool nsStr::Alloc(nsStr& aDest,PRUint32 aCount) {
   PRUint32 theSize=(theNewCapacity<<aDest.mCharSize);
   aDest.mStr = (char*)nsAllocator::Alloc(theSize);
 
-  PRBool result=PR_FALSE;
   if(aDest.mStr) {
     aDest.mOwnsBuffer=1;
-    result=PR_TRUE;
+    gStringAcquiredMemory=PR_TRUE;
   }
-  return result;
+  else gStringAcquiredMemory=PR_FALSE;
+  return gStringAcquiredMemory;
 }
 
 PRBool nsStr::Free(nsStr& aDest){
@@ -657,6 +663,16 @@ PRBool nsStr::Realloc(nsStr& aDest,PRUint32 aCount){
   return result;
 }
 
+/**
+ * Retrieve last memory error
+ *
+ * @update  gess 10/11/99
+ * @return  memory error (usually returns NS_OK)
+ */
+PRBool nsStr::DidAcquireMemory(void) {
+  return gStringAcquiredMemory;
+}
+
 //----------------------------------------------------------------------------------------
 
 CBufDescriptor::CBufDescriptor(char* aString,PRBool aStackBased,PRUint32 aCapacity,PRInt32 aLength) { 
diff --git a/mozilla/xpcom/string/obsolete/nsStr.h b/mozilla/xpcom/string/obsolete/nsStr.h
index 7f5c6c88273..b44eeb01358 100644
--- a/mozilla/xpcom/string/obsolete/nsStr.h
+++ b/mozilla/xpcom/string/obsolete/nsStr.h
@@ -45,17 +45,26 @@
 /***********************************************************************
   ASSUMPTIONS:
 
-    1. nsStrings and nsAutoString are always null terminated. 
-    2. If you try to set a null char (via SetChar()) a new length is set
-    3. nsCStrings can be upsampled into nsString without data loss
-    4. Char searching is faster than string searching. Use char interfaces
+    1. nsStrings and nsAutoString are always null terminated. However,
+       since it maintains a length byte, you can store NULL's inside
+       the string. Just be careful passing such buffers to 3rd party
+       API's that assume that NULL always terminate the buffer.
+
+    2. nsCStrings can be upsampled into nsString without data loss
+
+    3. Char searching is faster than string searching. Use char interfaces
        if your needs will allow it.
-    5. It's easy to use the stack for nsAutostring buffer storage (fast too!).
+
+    4. It's easy to use the stack for nsAutostring buffer storage (fast too!).
        See the CBufDescriptor class in this file.
-    6. It's ONLY ok to provide non-null-terminated buffers to Append() and Insert()
-       provided you specify a 0<n value for the optional count argument.
-    7. Downsampling from nsString to nsCString is lossy -- avoid it if possible!
-    8. Calls to ToNewCString() and ToNewUnicode() should be matched with calls to Recycle().
+
+    5. If you don't provide the optional count argument to Append() and Insert(),
+       the method will assume that the given buffer is terminated by the first
+       NULL it encounters.
+
+    6. Downsampling from nsString to nsCString can be lossy -- avoid it if possible!
+
+    7. Calls to ToNewCString() and ToNewUnicode() should be matched with calls to Recycle().
 
  ***********************************************************************/
 
@@ -399,6 +408,8 @@ struct NS_COM nsStr {
   static PRInt32 RFindChar(const nsStr& aDest,PRUnichar aChar, PRBool aIgnoreCase,PRInt32 anOffset);
   static PRInt32 RFindCharInSet(const nsStr& aDest,const nsStr& aSet,PRBool aIgnoreCase,PRInt32 anOffset);
 
+  static PRBool   DidAcquireMemory(void);
+
 
   PRUint32        mLength;
   PRUint32        mCapacity;
diff --git a/mozilla/xpcom/string/obsolete/nsString.cpp b/mozilla/xpcom/string/obsolete/nsString.cpp
index 43af1d45da6..cef4a597837 100644
--- a/mozilla/xpcom/string/obsolete/nsString.cpp
+++ b/mozilla/xpcom/string/obsolete/nsString.cpp
@@ -87,26 +87,7 @@ nsCString::nsCString(const char* aCString,PRInt32 aLength) {
  */
 nsCString::nsCString(const PRUnichar* aString,PRInt32 aLength)  {  
   nsStr::Initialize(*this,eOneByte);
-
-  if(aString && aLength){
-    nsStr temp;
-    Initialize(temp,eTwoByte);
-    temp.mUStr=(PRUnichar*)aString;
-
-    if(0<aLength) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
-      temp.mLength=aLength;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<(PRInt32)mLength)) {
-        aLength=temp.mLength=pos;
-      }
-    }
-    else aLength=temp.mLength=nsCRT::strlen(aString);
-
-    if(0<aLength)
-      nsStr::Append(*this,temp,0,aLength);
-  }
+  Assign(aString,aLength);
 }
 
 /**
@@ -248,12 +229,12 @@ PRBool nsCString::SetCharAt(PRUnichar aChar,PRUint32 anIndex){
   PRBool result=PR_FALSE;
   if(anIndex<mLength){
     mStr[anIndex]=(char)aChar;
-// SOON!   if(0==aChar) mLength=anIndex;
     result=PR_TRUE;
   }
   return result;
 }
 
+
 /*********************************************************
   append (operator+) METHODS....
  *********************************************************/
@@ -803,19 +784,21 @@ nsCString& nsCString::Assign(const char* aCString,PRInt32 aCount) {
 nsCString& nsCString::Assign(const PRUnichar* aString,PRInt32 aCount) {
   nsStr::Truncate(*this,0);
 
-  if(aString){
+  if(aString && aCount){
     nsStr temp;
     Initialize(temp,eTwoByte);
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in Assign(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
 
@@ -825,6 +808,7 @@ nsCString& nsCString::Assign(const PRUnichar* aString,PRInt32 aCount) {
   return *this;
 }
 
+
 /**
  * assign given unichar to this string
  * @update  gess 01/04/99
@@ -913,13 +897,15 @@ nsCString& nsCString::Append(const char* aCString,PRInt32 aCount) {
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Append(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
@@ -1099,13 +1085,15 @@ nsCString& nsCString::Insert(const char* aCString,PRUint32 anOffset,PRInt32 aCou
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
diff --git a/mozilla/xpcom/string/obsolete/nsString.h b/mozilla/xpcom/string/obsolete/nsString.h
index 27a0421e649..9c25db78800 100644
--- a/mozilla/xpcom/string/obsolete/nsString.h
+++ b/mozilla/xpcom/string/obsolete/nsString.h
@@ -398,8 +398,9 @@ public:
    */
   nsCString& operator+=(const nsCString& aString){return Append(aString,aString.mLength);}
   nsCString& operator+=(const char* aCString) {return Append(aCString);}
-  nsCString& operator+=(PRUnichar aChar){return Append(aChar);}
-  nsCString& operator+=(char aChar){return Append(aChar);}
+  nsCString& operator+=(const PRUnichar aChar){return Append(aChar);}
+  nsCString& operator+=(const char aChar){return Append(aChar);}
+  nsCString& operator+=(const int anInt){return Append(anInt,10);}
 
   /*
    *  Appends n characters from given string to this,
diff --git a/mozilla/xpcom/string/obsolete/nsString2.cpp b/mozilla/xpcom/string/obsolete/nsString2.cpp
index 83cbc8120f5..27321798c3b 100644
--- a/mozilla/xpcom/string/obsolete/nsString2.cpp
+++ b/mozilla/xpcom/string/obsolete/nsString2.cpp
@@ -72,9 +72,9 @@ nsString::nsString() {
  * @param   aCString is a ptr to a 1-byte cstr
  * @param   aLength tells us how many chars to copy from given CString
  */
-nsString::nsString(const char* aCString){  
+nsString::nsString(const char* aCString,PRInt32 aCount){  
   nsStr::Initialize(*this,eTwoByte);
-  Assign(aCString);
+  Assign(aCString,aCount);
 }
 
 /**
@@ -83,9 +83,9 @@ nsString::nsString(const char* aCString){
  * @param   aString is a ptr to a unichar string
  * @param   aLength tells us how many chars to copy from given aString
  */
-nsString::nsString(const PRUnichar* aString) {  
+nsString::nsString(const PRUnichar* aString,PRInt32 aCount) {  
   nsStr::Initialize(*this,eTwoByte);
-  Assign(aString);
+  Assign(aString,aCount);
 }
 
 /**
@@ -270,6 +270,7 @@ PRBool nsString::SetCharAt(PRUnichar aChar,PRUint32 anIndex){
   return result;
 }
 
+
 /*********************************************************
   append (operator+) METHODS....
  *********************************************************/
@@ -1037,13 +1038,15 @@ nsString& nsString::Append(const char* aCString,PRInt32 aCount) {
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in append(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
       
@@ -1067,13 +1070,15 @@ nsString& nsString::Append(const PRUnichar* aString,PRInt32 aCount) {
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in append(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
       
@@ -1255,13 +1260,15 @@ nsString& nsString::Insert(const char* aCString,PRUint32 anOffset,PRInt32 aCount
     temp.mStr=(char*)aCString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=strlen(aCString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(char*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aCString);
 
@@ -1288,13 +1295,15 @@ nsString& nsString::Insert(const PRUnichar* aString,PRUint32 anOffset,PRInt32 aC
     temp.mUStr=(PRUnichar*)aString;
 
     if(0<aCount) {
-        //this has to be done to make sure someone doesn't tell us
-        //aCount=n but offer a string whose len<aCount
       temp.mLength=aCount;
-      PRInt32 pos=nsStr::FindChar(temp,0,PR_FALSE,0);
-      if((0<=pos) && (pos<aCount)) {
-        aCount=temp.mLength=pos;
-      }
+
+      // If this assertion fires, the caller is probably lying about the length of
+      //   the passed-in string.  File a bug on the caller.
+#ifdef NS_DEBUG
+      PRInt32 len=nsCRT::strlen(aString);
+      NS_ASSERTION(aCount <= len, "potential error in Insert(PRUnichar*)");
+#endif
+
     }
     else aCount=temp.mLength=nsCRT::strlen(aString);
 
@@ -1699,7 +1708,9 @@ PRInt32 nsString::Compare(const char *aCString,PRBool aIgnoreCase,PRInt32 aCount
   if(aCString) {
     nsStr temp;
     nsStr::Initialize(temp,eOneByte);
-    temp.mLength=nsCRT::strlen(aCString);
+
+    temp.mLength= (0<aCount) ? aCount : nsCRT::strlen(aCString);
+
     temp.mStr=(char*)aCString;
     return nsStr::Compare(*this,temp,aCount,aIgnoreCase);
   }
@@ -1792,6 +1803,7 @@ PRBool nsString::EqualsIgnoreCase(const PRUnichar* s1, const PRUnichar* s2) cons
   return Equals(s1,s2,PR_TRUE);
 }
 
+
 /**
  * Compare this to given string; note that we compare full strings here.
  * 
diff --git a/mozilla/xpcom/string/obsolete/nsString2.h b/mozilla/xpcom/string/obsolete/nsString2.h
index 9cb0e8fd986..21bcb03461c 100644
--- a/mozilla/xpcom/string/obsolete/nsString2.h
+++ b/mozilla/xpcom/string/obsolete/nsString2.h
@@ -69,13 +69,13 @@ public:
    * This constructor accepts an isolatin string
    * @param   aCString is a ptr to a 1-byte cstr
    */
-  nsString(const char* aCString);
+  nsString(const char* aCString,PRInt32 aCount=-1);
 
   /**
    * This constructor accepts a unichar string
    * @param   aCString is a ptr to a 2-byte cstr
    */
-  nsString(const PRUnichar* aString);
+  nsString(const PRUnichar* aString,PRInt32 aCount=-1);
 
   /**
    * This is a copy constructor that accepts an nsStr
@@ -442,9 +442,10 @@ public:
   nsString& operator+=(const nsStr& aString){return Append(aString,aString.mLength);}
   nsString& operator+=(const nsString& aString){return Append(aString,aString.mLength);}
   nsString& operator+=(const char* aCString) {return Append(aCString);}
-  //nsString& operator+=(char aChar){return Append(aChar);}
+  nsString& operator+=(const char aChar) {return Append(PRUnichar(unsigned char(aChar)));}
   nsString& operator+=(const PRUnichar* aUCString) {return Append(aUCString);}
-  nsString& operator+=(PRUnichar aChar){return Append(aChar);}
+  nsString& operator+=(const PRUnichar aChar){return Append(aChar);}
+  nsString& operator+=(const int anInt){return Append(anInt,10);}
 
   /*
    *  Appends n characters from given string to this,