not yet part of the build, this new class provides a more consistent and flexible answer to the need for functions like |AppendInt| and |AppendFloat|. It is a short readable string produced with printf.

string/public/nsPrintfCString.h

@@ -0,0 +1,92 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 
+ * 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.org code.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are 
+ * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
+ * Rights Reserved.
+ * 
+ * Original Author:
+ *   Scott Collins <scc@mozilla.org>
+ *
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the
+ * terms of the GNU General Public License Version 2 or later (the
+ * "GPL"), in which case the provisions of the GPL are applicable 
+ * instead of those above.  If you wish to allow use of your 
+ * version of this file only under the terms of the GPL and not to
+ * allow others to use your version of this file under the MPL,
+ * indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by
+ * the GPL.  If you do not delete the provisions above, a recipient
+ * may use your version of this file under either the MPL or the
+ * GPL.
+ */
+
+#ifndef nsPrintfCString_h___
+#define nsPrintfCString_h___
+ 
+#include "nsAWritableString.h"
+
+
+  /**
+   * |nsPrintfCString| lets you use a formated |printf| string as an |nsAReadableCString|.
+   *
+   *   myCStr += nsPrintfCString("%f", 13.917);
+   *     // ...a general purpose substitute for |AppendFloat|
+   *
+   * For longer patterns, you'll want to use the constructor that takes a length
+   *
+   *   nsPrintfCString(128, "%f, %f, %f, %f, %f, %f, %f, %i, %f", x, y, z, 3.2, j, k, l, 3, 3.1);
+   *
+   * Exceding the default size (which you must specify in the constructor, it is not determined)
+   * causes an allocation, so avoid that.  If your formatted string exceeds the allocated space, it is
+   * cut off at the size of the buffer, no error is reported (and no out-of-bounds writing occurs).
+   * This class is intended to be useful for numbers and short
+   * strings, not arbitrary formatting of other strings (e.g., with %s).  There is currently no
+   * wide version of this class, since wide |printf| is not generally available.  That means
+   * to get a wide version of your formatted data, you must, e.g.,
+   *
+   *   CopyASCIItoUCS2(nsPrintfCString("%f", 13.917"), myStr);
+   *
+   * That's another good reason to avoid this class for anything but numbers ... as strings can be
+   * much more efficiently handled with |NS_LITERAL_[C]STRING| and |nsLiteral[C]String|.
+   */
+
+class nsPrintfCString
+    : public nsAReadableCString
+  {
+    static const int kLocalBufferSize = 15;
+      // ought to be large enough for most things ... a |long long| needs at most 20 (so you'd better ask)
+      //  pinkerton suggests 7.  We should measure and decide what's appropriate
+
+
+    public:
+      explicit nsPrintfCString( const char* format, ... );
+      nsPrintfCString( size_t n, const char* format, ...);
+     ~nsPrintfCString();
+
+      virtual PRUint32 Length() const;
+
+    protected:
+      virtual PRBool GetReadableFragment( nsReadableFragment<char>& aFragment, nsFragmentRequest aRequest ) const;
+
+    private:
+      char*     mStart;
+      PRUint32  mLength;
+      char      mLocalBuffer[ kLocalBufferSize + 1 ];
+  };
+
+#endif // !defined(nsPrintfCString_h___)

string/src/nsPrintfCString.cpp

@@ -0,0 +1,114 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 
+ * 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.org code.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are 
+ * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
+ * Rights Reserved.
+ * 
+ * Original Author:
+ *   Scott Collins <scc@mozilla.org>
+ *
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the
+ * terms of the GNU General Public License Version 2 or later (the
+ * "GPL"), in which case the provisions of the GPL are applicable 
+ * instead of those above.  If you wish to allow use of your 
+ * version of this file only under the terms of the GPL and not to
+ * allow others to use your version of this file under the MPL,
+ * indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by
+ * the GPL.  If you do not delete the provisions above, a recipient
+ * may use your version of this file under either the MPL or the
+ * GPL.
+ */
+
+#include "nsPrintfCString.h"
+#include <stdarg.h>
+#include "prprf.h"
+
+
+nsPrintfCString::nsPrintfCString( const char* format, ... )
+    : mStart(mLocalBuffer),
+      mLength(0)
+  {
+    va_list ap;
+
+    size_t logical_capacity = kLocalBufferSize;
+    size_t physical_capacity = logical_capacity + 1;
+
+    va_start(ap, format);
+    mLength = PR_vsnprintf(mStart, physical_capacity, format, ap);
+    va_end(ap);
+  }
+
+nsPrintfCString::nsPrintfCString( size_t n, const char* format, ... )
+    : mStart(mLocalBuffer),
+      mLength(0)
+  {
+    va_list ap;
+
+      // make sure there's at least |n| space
+    size_t logical_capacity = kLocalBufferSize;
+    if ( n > logical_capacity )
+      {
+        char* nonlocal_buffer = new char[n];
+
+          // if we got something, use it
+        if ( nonlocal_buffer )
+          {
+            mStart = nonlocal_buffer;
+            logical_capacity = n;
+          }
+        // else, it's the error case ... we'll use what space we have
+        //  (since we can't throw)
+      }
+    size_t physical_capacity = logical_capacity + 1;
+
+    va_start(ap, format);
+    mLength = PR_vsnprintf(mStart, physical_capacity, format, ap);
+    va_end(ap);
+  }
+
+nsPrintfCString::~nsPrintfCString()
+  {
+    if ( mStart != mLocalBuffer )
+      delete [] mStart;
+  }
+
+PRUint32
+nsPrintfCString::Length() const
+  {
+    return mLength;
+  }
+
+PRBool
+nsPrintfCString::GetReadableFragment( nsReadableFragment<char>& aFragment, nsFragmentRequest aRequest ) const
+  {
+    switch ( aRequest )
+      {
+        case kFirstFragment:
+        case kLastFragment:
+          aFragment.mFragmentIdentifier = this;
+          // fall through
+        case kThisFragment:
+          aFragment.mStart = mStart;
+          aFragment.mEnd = mStart + mLength;
+          return PR_TRUE;
+
+        default:
+          return PR_FALSE;
+      }
+  }

xpcom/ds/nsPrintfCString.cpp

@@ -0,0 +1,114 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 
+ * 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.org code.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are 
+ * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
+ * Rights Reserved.
+ * 
+ * Original Author:
+ *   Scott Collins <scc@mozilla.org>
+ *
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the
+ * terms of the GNU General Public License Version 2 or later (the
+ * "GPL"), in which case the provisions of the GPL are applicable 
+ * instead of those above.  If you wish to allow use of your 
+ * version of this file only under the terms of the GPL and not to
+ * allow others to use your version of this file under the MPL,
+ * indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by
+ * the GPL.  If you do not delete the provisions above, a recipient
+ * may use your version of this file under either the MPL or the
+ * GPL.
+ */
+
+#include "nsPrintfCString.h"
+#include <stdarg.h>
+#include "prprf.h"
+
+
+nsPrintfCString::nsPrintfCString( const char* format, ... )
+    : mStart(mLocalBuffer),
+      mLength(0)
+  {
+    va_list ap;
+
+    size_t logical_capacity = kLocalBufferSize;
+    size_t physical_capacity = logical_capacity + 1;
+
+    va_start(ap, format);
+    mLength = PR_vsnprintf(mStart, physical_capacity, format, ap);
+    va_end(ap);
+  }
+
+nsPrintfCString::nsPrintfCString( size_t n, const char* format, ... )
+    : mStart(mLocalBuffer),
+      mLength(0)
+  {
+    va_list ap;
+
+      // make sure there's at least |n| space
+    size_t logical_capacity = kLocalBufferSize;
+    if ( n > logical_capacity )
+      {
+        char* nonlocal_buffer = new char[n];
+
+          // if we got something, use it
+        if ( nonlocal_buffer )
+          {
+            mStart = nonlocal_buffer;
+            logical_capacity = n;
+          }
+        // else, it's the error case ... we'll use what space we have
+        //  (since we can't throw)
+      }
+    size_t physical_capacity = logical_capacity + 1;
+
+    va_start(ap, format);
+    mLength = PR_vsnprintf(mStart, physical_capacity, format, ap);
+    va_end(ap);
+  }
+
+nsPrintfCString::~nsPrintfCString()
+  {
+    if ( mStart != mLocalBuffer )
+      delete [] mStart;
+  }
+
+PRUint32
+nsPrintfCString::Length() const
+  {
+    return mLength;
+  }
+
+PRBool
+nsPrintfCString::GetReadableFragment( nsReadableFragment<char>& aFragment, nsFragmentRequest aRequest ) const
+  {
+    switch ( aRequest )
+      {
+        case kFirstFragment:
+        case kLastFragment:
+          aFragment.mFragmentIdentifier = this;
+          // fall through
+        case kThisFragment:
+          aFragment.mStart = mStart;
+          aFragment.mEnd = mStart + mLength;
+          return PR_TRUE;
+
+        default:
+          return PR_FALSE;
+      }
+  }

xpcom/ds/nsPrintfCString.h

@@ -0,0 +1,92 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 
+ * 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.org code.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are 
+ * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
+ * Rights Reserved.
+ * 
+ * Original Author:
+ *   Scott Collins <scc@mozilla.org>
+ *
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the
+ * terms of the GNU General Public License Version 2 or later (the
+ * "GPL"), in which case the provisions of the GPL are applicable 
+ * instead of those above.  If you wish to allow use of your 
+ * version of this file only under the terms of the GPL and not to
+ * allow others to use your version of this file under the MPL,
+ * indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by
+ * the GPL.  If you do not delete the provisions above, a recipient
+ * may use your version of this file under either the MPL or the
+ * GPL.
+ */
+
+#ifndef nsPrintfCString_h___
+#define nsPrintfCString_h___
+ 
+#include "nsAWritableString.h"
+
+
+  /**
+   * |nsPrintfCString| lets you use a formated |printf| string as an |nsAReadableCString|.
+   *
+   *   myCStr += nsPrintfCString("%f", 13.917);
+   *     // ...a general purpose substitute for |AppendFloat|
+   *
+   * For longer patterns, you'll want to use the constructor that takes a length
+   *
+   *   nsPrintfCString(128, "%f, %f, %f, %f, %f, %f, %f, %i, %f", x, y, z, 3.2, j, k, l, 3, 3.1);
+   *
+   * Exceding the default size (which you must specify in the constructor, it is not determined)
+   * causes an allocation, so avoid that.  If your formatted string exceeds the allocated space, it is
+   * cut off at the size of the buffer, no error is reported (and no out-of-bounds writing occurs).
+   * This class is intended to be useful for numbers and short
+   * strings, not arbitrary formatting of other strings (e.g., with %s).  There is currently no
+   * wide version of this class, since wide |printf| is not generally available.  That means
+   * to get a wide version of your formatted data, you must, e.g.,
+   *
+   *   CopyASCIItoUCS2(nsPrintfCString("%f", 13.917"), myStr);
+   *
+   * That's another good reason to avoid this class for anything but numbers ... as strings can be
+   * much more efficiently handled with |NS_LITERAL_[C]STRING| and |nsLiteral[C]String|.
+   */
+
+class nsPrintfCString
+    : public nsAReadableCString
+  {
+    static const int kLocalBufferSize = 15;
+      // ought to be large enough for most things ... a |long long| needs at most 20 (so you'd better ask)
+      //  pinkerton suggests 7.  We should measure and decide what's appropriate
+
+
+    public:
+      explicit nsPrintfCString( const char* format, ... );
+      nsPrintfCString( size_t n, const char* format, ...);
+     ~nsPrintfCString();
+
+      virtual PRUint32 Length() const;
+
+    protected:
+      virtual PRBool GetReadableFragment( nsReadableFragment<char>& aFragment, nsFragmentRequest aRequest ) const;
+
+    private:
+      char*     mStart;
+      PRUint32  mLength;
+      char      mLocalBuffer[ kLocalBufferSize + 1 ];
+  };
+
+#endif // !defined(nsPrintfCString_h___)

xpcom/string/public/nsPrintfCString.h

@@ -0,0 +1,92 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 
+ * 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.org code.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are 
+ * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
+ * Rights Reserved.
+ * 
+ * Original Author:
+ *   Scott Collins <scc@mozilla.org>
+ *
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the
+ * terms of the GNU General Public License Version 2 or later (the
+ * "GPL"), in which case the provisions of the GPL are applicable 
+ * instead of those above.  If you wish to allow use of your 
+ * version of this file only under the terms of the GPL and not to
+ * allow others to use your version of this file under the MPL,
+ * indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by
+ * the GPL.  If you do not delete the provisions above, a recipient
+ * may use your version of this file under either the MPL or the
+ * GPL.
+ */
+
+#ifndef nsPrintfCString_h___
+#define nsPrintfCString_h___
+ 
+#include "nsAWritableString.h"
+
+
+  /**
+   * |nsPrintfCString| lets you use a formated |printf| string as an |nsAReadableCString|.
+   *
+   *   myCStr += nsPrintfCString("%f", 13.917);
+   *     // ...a general purpose substitute for |AppendFloat|
+   *
+   * For longer patterns, you'll want to use the constructor that takes a length
+   *
+   *   nsPrintfCString(128, "%f, %f, %f, %f, %f, %f, %f, %i, %f", x, y, z, 3.2, j, k, l, 3, 3.1);
+   *
+   * Exceding the default size (which you must specify in the constructor, it is not determined)
+   * causes an allocation, so avoid that.  If your formatted string exceeds the allocated space, it is
+   * cut off at the size of the buffer, no error is reported (and no out-of-bounds writing occurs).
+   * This class is intended to be useful for numbers and short
+   * strings, not arbitrary formatting of other strings (e.g., with %s).  There is currently no
+   * wide version of this class, since wide |printf| is not generally available.  That means
+   * to get a wide version of your formatted data, you must, e.g.,
+   *
+   *   CopyASCIItoUCS2(nsPrintfCString("%f", 13.917"), myStr);
+   *
+   * That's another good reason to avoid this class for anything but numbers ... as strings can be
+   * much more efficiently handled with |NS_LITERAL_[C]STRING| and |nsLiteral[C]String|.
+   */
+
+class nsPrintfCString
+    : public nsAReadableCString
+  {
+    static const int kLocalBufferSize = 15;
+      // ought to be large enough for most things ... a |long long| needs at most 20 (so you'd better ask)
+      //  pinkerton suggests 7.  We should measure and decide what's appropriate
+
+
+    public:
+      explicit nsPrintfCString( const char* format, ... );
+      nsPrintfCString( size_t n, const char* format, ...);
+     ~nsPrintfCString();
+
+      virtual PRUint32 Length() const;
+
+    protected:
+      virtual PRBool GetReadableFragment( nsReadableFragment<char>& aFragment, nsFragmentRequest aRequest ) const;
+
+    private:
+      char*     mStart;
+      PRUint32  mLength;
+      char      mLocalBuffer[ kLocalBufferSize + 1 ];
+  };
+
+#endif // !defined(nsPrintfCString_h___)

xpcom/string/src/nsPrintfCString.cpp

@@ -0,0 +1,114 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 
+ * 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.org code.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are 
+ * Copyright (C) 1994-2000 Netscape Communications Corporation.  All
+ * Rights Reserved.
+ * 
+ * Original Author:
+ *   Scott Collins <scc@mozilla.org>
+ *
+ * Contributor(s):
+ * 
+ * Alternatively, the contents of this file may be used under the
+ * terms of the GNU General Public License Version 2 or later (the
+ * "GPL"), in which case the provisions of the GPL are applicable 
+ * instead of those above.  If you wish to allow use of your 
+ * version of this file only under the terms of the GPL and not to
+ * allow others to use your version of this file under the MPL,
+ * indicate your decision by deleting the provisions above and
+ * replace them with the notice and other provisions required by
+ * the GPL.  If you do not delete the provisions above, a recipient
+ * may use your version of this file under either the MPL or the
+ * GPL.
+ */
+
+#include "nsPrintfCString.h"
+#include <stdarg.h>
+#include "prprf.h"
+
+
+nsPrintfCString::nsPrintfCString( const char* format, ... )
+    : mStart(mLocalBuffer),
+      mLength(0)
+  {
+    va_list ap;
+
+    size_t logical_capacity = kLocalBufferSize;
+    size_t physical_capacity = logical_capacity + 1;
+
+    va_start(ap, format);
+    mLength = PR_vsnprintf(mStart, physical_capacity, format, ap);
+    va_end(ap);
+  }
+
+nsPrintfCString::nsPrintfCString( size_t n, const char* format, ... )
+    : mStart(mLocalBuffer),
+      mLength(0)
+  {
+    va_list ap;
+
+      // make sure there's at least |n| space
+    size_t logical_capacity = kLocalBufferSize;
+    if ( n > logical_capacity )
+      {
+        char* nonlocal_buffer = new char[n];
+
+          // if we got something, use it
+        if ( nonlocal_buffer )
+          {
+            mStart = nonlocal_buffer;
+            logical_capacity = n;
+          }
+        // else, it's the error case ... we'll use what space we have
+        //  (since we can't throw)
+      }
+    size_t physical_capacity = logical_capacity + 1;
+
+    va_start(ap, format);
+    mLength = PR_vsnprintf(mStart, physical_capacity, format, ap);
+    va_end(ap);
+  }
+
+nsPrintfCString::~nsPrintfCString()
+  {
+    if ( mStart != mLocalBuffer )
+      delete [] mStart;
+  }
+
+PRUint32
+nsPrintfCString::Length() const
+  {
+    return mLength;
+  }
+
+PRBool
+nsPrintfCString::GetReadableFragment( nsReadableFragment<char>& aFragment, nsFragmentRequest aRequest ) const
+  {
+    switch ( aRequest )
+      {
+        case kFirstFragment:
+        case kLastFragment:
+          aFragment.mFragmentIdentifier = this;
+          // fall through
+        case kThisFragment:
+          aFragment.mStart = mStart;
+          aFragment.mEnd = mStart + mLength;
+          return PR_TRUE;
+
+        default:
+          return PR_FALSE;
+      }
+  }