Do proper memory freeing to prevent leaks.

* include/freetype/internal/ftobjs.h: Create a new flag named
`FT_GLYPH_OWN_GZIP_SVG' to indicate that `svg_document' in
`slot->other' is GZIP compressed and has to be freed later.

* src/base/ftglyph.c: Minor styling.

* src/base/ftobjs.c: Add code to free memory that was previously
allocated for storing GZIP compressed SVG documents.

* src/sfnt/ttsvg.c: Set the `FT_GLYPH_OWN_GZIP_SVG' flag if the
document is GZIP compressed.

include/freetype/internal/ftobjs.h

@@ -418,7 +418,8 @@ FT_BEGIN_HEADER
    *     initializing the glyph slot.
    */
 
-#define FT_GLYPH_OWN_BITMAP  0x1U
+#define FT_GLYPH_OWN_BITMAP    0x1U
+#define FT_GLYPH_OWN_GZIP_SVG  0x2U
 
   typedef struct  FT_Slot_InternalRec_
   {

src/base/ftglyph.c

@@ -378,10 +378,13 @@
     target->metrics             = source->metrics;
 
     /* allocate space for the svg document */
-    target->svg_document = memory->alloc( memory, target->svg_document_length );
+    target->svg_document = memory->alloc( memory,
+                                          target->svg_document_length );
 
     /* copy the stuff */
-    FT_MEM_COPY( target->svg_document, source->svg_document, target->svg_document_length );
+    FT_MEM_COPY( target->svg_document,
+                 source->svg_document,
+                 target->svg_document_length );
 
     return error;
   }
@@ -396,6 +399,7 @@
 
     FT_SVG_Document  document;
 
+    /* TODO: (OT-SVG) this probably creates a memory leak. Fix it */
     if ( FT_NEW( document ) )
       return error;
 

src/base/ftobjs.c

@@ -561,8 +561,19 @@
     slot->subglyphs     = NULL;
     slot->control_data  = NULL;
     slot->control_len   = 0;
+
     if ( !( slot->face->face_flags & FT_FACE_FLAG_SVG ) )
       slot->other         = NULL;
+    {
+      if ( slot->internal->flags & FT_GLYPH_OWN_GZIP_SVG )
+      {
+        FT_Memory        memory = slot->face->memory;
+        FT_SVG_Document  doc    = (FT_SVG_Document)slot->other;
+        FT_FREE( doc->svg_document );
+        slot->internal->load_flags &= ~FT_GLYPH_OWN_GZIP_SVG;
+      }
+    }
+
     slot->format        = FT_GLYPH_FORMAT_NONE;
 
     slot->linearHoriAdvance = 0;
@@ -582,6 +593,13 @@
 
     if ( slot->face->face_flags & FT_FACE_FLAG_SVG )
     {
+      /* free memory in case svg was there */
+      if ( slot->internal->flags & FT_GLYPH_OWN_GZIP_SVG )
+      {
+        FT_SVG_Document  doc    = (FT_SVG_Document)slot->other;
+        FT_FREE( doc->svg_document );
+        slot->internal->flags &= ~FT_GLYPH_OWN_GZIP_SVG;
+      }
       FT_FREE( slot->other );
     }
 

src/sfnt/ttsvg.c

@@ -26,6 +26,7 @@
 
 #include <ft2build.h>
 #include FT_INTERNAL_STREAM_H
+#include FT_INTERNAL_OBJECTS_H
 #include FT_TRUETYPE_TAGS_H
 #include FT_GZIP_H
 #include FT_SVG_RENDERER_H
@@ -214,8 +215,8 @@
                     (FT_ULong)doc_list[doc_length - 3] << 8  |
                     (FT_ULong)doc_list[doc_length - 4];
 
-      /* TODO: (OT-SVG) memory allocated here needs to be freed somewhere */
       uncomp_buffer = (FT_Byte*) memory->alloc(memory, uncomp_size);
+      glyph->internal->flags |= FT_GLYPH_OWN_GZIP_SVG;
       error = FT_Gzip_Uncompress( memory, uncomp_buffer, &uncomp_size,
                                           doc_list,      doc_length  );
       if ( error != FT_Err_Ok )