Fixing bug 236595. Making nsAdoptingString not adopt strings that aren't owned by the string that's adopted from. Also un-inlining operator=(const self_type&). r+sr=darin@meer.net

xpcom/build/dlldeps.cpp

@@ -190,4 +190,12 @@ void XXXNeverCalled()
     NS_StringSetData(str1, nsnull, 0);
     NS_StringSetDataRange(str1, 0, 0, nsnull, 0);
     NS_StringCopy(str1, str1);
+    {
+      nsAdoptingCString foo, bar;
+      foo = bar;
+    }
+    {
+      nsAdoptingString foo, bar;
+      foo = bar;
+    }
 }

xpcom/string/public/nsTString.h

@@ -685,9 +685,12 @@ getter_Copies( nsTXPIDLString_CharT& aString )
 
 
   /**
-   * nsTAdoptString extends nsTXPIDString such that:
+   * nsTAdoptingString extends nsTXPIDLString such that:
    *
-   *   (1) Adopt given string on construction or assignment
+   * (1) Adopt given string on construction or assignment, i.e. take
+   * the value of what's given, and make what's given forget its
+   * value. Note that this class violates constness in a few
+   * places. Be careful!
    */
 class nsTAdoptingString_CharT : public nsTXPIDLString_CharT
   {
@@ -697,12 +700,16 @@ class nsTAdoptingString_CharT : public nsTXPIDLString_CharT
 
     public:
 
+      explicit nsTAdoptingString_CharT() {}
       explicit nsTAdoptingString_CharT(char_type* str, size_type length = size_type(-1))
         {
           Adopt(str, length);
         }
 
-        // copy-constructor required to adopt on copy
+        // copy-constructor required to adopt on copy. Note that this
+        // will violate the constness of |str| in the operator=()
+        // call. |str| will be truncated as a side-effect of this
+        // constructor.
       nsTAdoptingString_CharT( const self_type& str )
         {
           *this = str;
@@ -713,25 +720,14 @@ class nsTAdoptingString_CharT : public nsTXPIDLString_CharT
       self_type& operator=( const substring_tuple_type& tuple )                                 { Assign(tuple);    return *this; }
       self_type& operator=( const abstract_string_type& readable )                              { Assign(readable); return *this; }
 
-
-        // Adopt() when assigning to a const self_type&
-      self_type& operator=( const self_type& str )
-        {
-          Adopt(str.mData, str.mLength);
-
-          self_type* mutable_str = NS_CONST_CAST(self_type*, &str);
-
-          // Make str forget the buffer we just took ownership of.
-          new (mutable_str) self_type();
-
-          return *this;
-        }
+        // Adopt(), if possible, when assigning to a self_type&. Note
+        // that this violates the constness of str, str is always
+        // truncated when this operator is called.
+      NS_COM self_type& operator=( const self_type& str );
 
     private:
         // NOT TO BE IMPLEMENTED.
       self_type& operator=( const char_type* data );
       self_type& operator=( char_type* data );
-
-      explicit nsTAdoptingString_CharT() {}
   };
 

xpcom/string/src/Makefile.in

@@ -44,6 +44,7 @@ CPPSRCS		=				\
 		nsReadableUtils.cpp		\
 		nsSubstring.cpp			\
 		nsSubstringTuple.cpp		\
+		nsString.cpp			\
 		nsStringAPI.cpp			\
 		nsStringComparator.cpp		\
 		nsStringObsolete.cpp		\

xpcom/string/src/nsString.cpp

@@ -0,0 +1,49 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla.
+ *
+ * The Initial Developer of the Original Code is IBM Corporation.
+ * Portions created by IBM Corporation are Copyright (C) 2003
+ * IBM Corporation. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Darin Fisher <darin@meer.net>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "nsString.h"
+
+  // define nsString
+#include "string-template-def-unichar.h"
+#include "nsTString.cpp"
+#include "string-template-undef.h"
+
+  // define nsCString
+#include "string-template-def-char.h"
+#include "nsTString.cpp"
+#include "string-template-undef.h"

xpcom/string/src/nsTString.cpp

@@ -0,0 +1,63 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla.
+ *
+ * The Initial Developer of the Original Code is IBM Corporation.
+ * Portions created by IBM Corporation are Copyright (C) 2003
+ * IBM Corporation. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Darin Fisher <darin@meer.net>
+ *   Johnny Stenback <jst@mozilla.jstenback.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+NS_COM nsTAdoptingString_CharT&
+nsTAdoptingString_CharT::operator=( const self_type& str )
+  {
+    // This'll violate the constness of this argument, that's just
+    // the nature of this class...
+    self_type* mutable_str = NS_CONST_CAST(self_type*, &str);
+
+    if (str.mFlags & F_OWNED)
+      {
+        Adopt(str.mData, str.mLength);
+
+        // Make str forget the buffer we just took ownership of.
+        new (mutable_str) self_type();
+      }
+    else
+      {
+        Assign(str);
+
+        mutable_str->Truncate();
+      }
+
+    return *this;
+  }
+