fixed a potential memory leak when loading embedded bitmaps

CHANGES

@@ -53,6 +53,9 @@ LATEST CHANGES -
   - updated the tutorial (not finished though).
   - updated the top-level BUILD  document
 
+  - fixed a potential memory leak that could occur when loading embedded
+    bitmaps.
+
   - added the declaration of FT_New_Memory_Face in <freetype/freetype.h>, as
     it was missing from the public header (the implementation was already
     in "ftobjs.c").

include/freetype/freetype.h

@@ -1304,10 +1304,17 @@
   /*                returned by FT_Load_Glyph().                           */
   /*                                                                       */
   /*                                                                       */
+  
+  enum
+  {
+    ft_glyph_own_bitmap = 1
+  };
+  
   typedef struct  FT_GlyphSlotRec_
   {
     FT_Face           face;
     FT_GlyphSlot      next;
+    FT_UInt           flags;
 
     FT_Glyph_Metrics  metrics;
     FT_Glyph_Metrics  metrics2;

src/sfnt/ttsbit.c

@@ -1403,7 +1403,9 @@
     ebdt_pos = FILE_Pos();
 
     /* clear the bitmap & load the bitmap */
+    if (face->root.glyph->flags & ft_glyph_own_bitmap)
       FREE( map->buffer );
+      
     map->rows = map->pitch = map->width = 0;
 
     error = Load_SBit_Image( strike, range, ebdt_pos, glyph_offset,
@@ -1411,6 +1413,9 @@
     if ( error )
       goto Exit;
 
+    /* the glyph slot owns this bitmap buffer */
+    face->root.glyph->flags |= ft_glyph_own_bitmap;
+    
     /* setup vertical metrics if needed */
     if ( strike->flags & 1 )
     {

src/truetype/ttobjs.c

@@ -806,7 +806,10 @@
   void  TT_Done_GlyphSlot( TT_GlyphSlot  slot )
   {
     FT_Library  library = slot->face->driver->library;
+    FT_Memory   memory  = library->memory;
 
+    if (slot->flags & ft_glyph_own_bitmap)
+      FREE( slot->bitmap.buffer );
 
     FT_Outline_Done( library, &slot->outline );
     return;