* src/sfnt/sfdriver.c, src/sfnt/ttbdf.c: Clean up interface.

Ensure that all driver functions use the signature of the service or driver.
This avoids pointer mismatches, which are technically undefined behaviour.
Recent compilers are more picky in catching them as part of Control Flow
Integrity tests.

* src/sfnt/sfdriver.c (sfnt_load_table): New wrapper function.
(sfnt_service_sfnt_table): Use it.

3 files changed, 66 insertions, 44 deletions

diff --git a/src/sfnt/sfdriver.c b/src/sfnt/sfdriver.c
index 70c63417b..cb8ab440e 100644
--- a/src/sfnt/sfdriver.c
+++ b/src/sfnt/sfdriver.c
@@ -79,41 +79,57 @@
    *
    */
 
-  static void*
-  get_sfnt_table( TT_Face      face,
+  FT_CALLBACK_DEF( FT_Error )
+  sfnt_load_table( FT_Face    face,    /* TT_Face */
+                   FT_ULong   tag,
+                   FT_Long    offset,
+                   FT_Byte*   buffer,
+                   FT_ULong*  length )
+  {
+    TT_Face  ttface = (TT_Face)face;
+
+
+    return tt_face_load_any( ttface, tag, offset, buffer, length );
+  }
+
+
+  FT_CALLBACK_DEF( void* )
+  get_sfnt_table( FT_Face      face,  /* TT_Face */
                   FT_Sfnt_Tag  tag )
   {
+    TT_Face  ttface = (TT_Face)face;
+
     void*  table;
 
 
     switch ( tag )
     {
     case FT_SFNT_HEAD:
-      table = &face->header;
+      table = &ttface->header;
       break;
 
     case FT_SFNT_HHEA:
-      table = &face->horizontal;
+      table = &ttface->horizontal;
       break;
 
     case FT_SFNT_VHEA:
-      table = face->vertical_info ? &face->vertical : NULL;
+      table = ttface->vertical_info ? &ttface->vertical : NULL;
       break;
 
     case FT_SFNT_OS2:
-      table = ( face->os2.version == 0xFFFFU ) ? NULL : &face->os2;
+      table = ( ttface->os2.version == 0xFFFFU ) ? NULL : &ttface->os2;
       break;
 
     case FT_SFNT_POST:
-      table = &face->postscript;
+      table = &ttface->postscript;
       break;
 
     case FT_SFNT_MAXP:
-      table = &face->max_profile;
+      table = &ttface->max_profile;
       break;
 
     case FT_SFNT_PCLT:
-      table = face->pclt.Version ? &face->pclt : NULL;
+      table = ttface->pclt.Version ? &ttface->pclt : NULL;
       break;
 
     default:
@@ -124,26 +140,29 @@
   }
 
 
-  static FT_Error
-  sfnt_table_info( TT_Face    face,
+  FT_CALLBACK_DEF( FT_Error )
+  sfnt_table_info( FT_Face    face,    /* TT_Face */
                    FT_UInt    idx,
                    FT_ULong  *tag,
                    FT_ULong  *offset,
                    FT_ULong  *length )
   {
+    TT_Face  ttface = (TT_Face)face;
+
+
     if ( !offset || !length )
       return FT_THROW( Invalid_Argument );
 
     if ( !tag )
-      *length = face->num_tables;
+      *length = ttface->num_tables;
     else
     {
-      if ( idx >= face->num_tables )
+      if ( idx >= ttface->num_tables )
         return FT_THROW( Table_Missing );
 
-      *tag    = face->dir_tables[idx].Tag;
-      *offset = face->dir_tables[idx].Offset;
-      *length = face->dir_tables[idx].Length;
+      *tag    = ttface->dir_tables[idx].Tag;
+      *offset = ttface->dir_tables[idx].Offset;
+      *length = ttface->dir_tables[idx].Length;
     }
 
     return FT_Err_Ok;
@@ -153,7 +172,7 @@
   FT_DEFINE_SERVICE_SFNT_TABLEREC(
     sfnt_service_sfnt_table,
 
-    (FT_SFNT_TableLoadFunc)tt_face_load_any,     /* load_table */
+    (FT_SFNT_TableLoadFunc)sfnt_load_table,      /* load_table */
     (FT_SFNT_TableGetFunc) get_sfnt_table,       /* get_table  */
     (FT_SFNT_TableInfoFunc)sfnt_table_info       /* table_info */
   )
@@ -166,7 +185,7 @@
    *
    */
 
-  static FT_Error
+  FT_CALLBACK_DEF( FT_Error )
   sfnt_get_glyph_name( FT_Face     face,
                        FT_UInt     glyph_index,
                        FT_Pointer  buffer,
@@ -184,7 +203,7 @@
   }
 
 
-  static FT_UInt
+  FT_CALLBACK_DEF( FT_UInt )
   sfnt_get_name_index( FT_Face           face,
                        const FT_String*  glyph_name )
   {
@@ -600,7 +619,7 @@
   }
 
 
-  static FT_Bool
+  FT_CALLBACK_DEF( FT_Bool )
   sfnt_get_name_id( TT_Face    face,
                     FT_UShort  id,
                     FT_Int    *win,
@@ -1043,47 +1062,49 @@
 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
 
 
-  static const char*
-  sfnt_get_ps_name( TT_Face  face )
+  FT_CALLBACK_DEF( const char* )
+  sfnt_get_ps_name( FT_Face  face )    /* TT_Face */
   {
+    TT_Face  ttface = (TT_Face)face;
+
     FT_Int       found, win, apple;
     const char*  result = NULL;
 
 
-    if ( face->postscript_name )
-      return face->postscript_name;
+    if ( ttface->postscript_name )
+      return ttface->postscript_name;
 
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
-    if ( face->blend                                 &&
-         ( FT_IS_NAMED_INSTANCE( FT_FACE( face ) ) ||
-           FT_IS_VARIATION( FT_FACE( face ) )      ) )
+    if ( ttface->blend                    &&
+         ( FT_IS_NAMED_INSTANCE( face ) ||
+           FT_IS_VARIATION( face )      ) )
     {
-      face->postscript_name = sfnt_get_var_ps_name( face );
-      return face->postscript_name;
+      ttface->postscript_name = sfnt_get_var_ps_name( ttface );
+      return ttface->postscript_name;
     }
 #endif
 
     /* scan the name table to see whether we have a Postscript name here, */
     /* either in Macintosh or Windows platform encodings                  */
-    found = sfnt_get_name_id( face, TT_NAME_ID_PS_NAME, &win, &apple );
+    found = sfnt_get_name_id( ttface, TT_NAME_ID_PS_NAME, &win, &apple );
     if ( !found )
       return NULL;
 
     /* prefer Windows entries over Apple */
     if ( win != -1 )
-      result = get_win_string( face->root.memory,
-                               face->name_table.stream,
-                               face->name_table.names + win,
+      result = get_win_string( FT_FACE_MEMORY( face ),
+                               ttface->name_table.stream,
+                               ttface->name_table.names + win,
                                sfnt_is_postscript,
                                1 );
     if ( !result && apple != -1 )
-      result = get_apple_string( face->root.memory,
-                                 face->name_table.stream,
-                                 face->name_table.names + apple,
+      result = get_apple_string( FT_FACE_MEMORY( face ),
+                                 ttface->name_table.stream,
+                                 ttface->name_table.names + apple,
                                  sfnt_is_postscript,
                                  1 );
 
-    face->postscript_name = result;
+    ttface->postscript_name = result;
 
     return result;
   }
@@ -1109,7 +1130,7 @@
 #ifdef TT_CONFIG_OPTION_BDF
 
   static FT_Error
-  sfnt_get_charset_id( TT_Face       face,
+  sfnt_get_charset_id( FT_Face       face,
                        const char*  *acharset_encoding,
                        const char*  *acharset_registry )
   {
diff --git a/src/sfnt/ttbdf.c b/src/sfnt/ttbdf.c
index c4d0035ea..536fa7467 100644
--- a/src/sfnt/ttbdf.c
+++ b/src/sfnt/ttbdf.c
@@ -136,13 +136,14 @@
 
 
   FT_LOCAL_DEF( FT_Error )
-  tt_face_find_bdf_prop( TT_Face           face,
+  tt_face_find_bdf_prop( FT_Face           face,          /* TT_Face */
                          const char*       property_name,
                          BDF_PropertyRec  *aprop )
   {
-    TT_BDF     bdf   = &face->bdf;
-    FT_Size    size  = FT_FACE( face )->size;
-    FT_Error   error = FT_Err_Ok;
+    TT_Face    ttface = (TT_Face)face;
+    TT_BDF     bdf    = &ttface->bdf;
+    FT_Size    size   = FT_FACE_SIZE( face );
+    FT_Error   error  = FT_Err_Ok;
     FT_Byte*   p;
     FT_UInt    count;
     FT_Byte*   strike;
@@ -153,7 +154,7 @@
 
     if ( bdf->loaded == 0 )
     {
-      error = tt_face_load_bdf_props( face, FT_FACE( face )->stream );
+      error = tt_face_load_bdf_props( ttface, FT_FACE_STREAM( face ) );
       if ( error )
         goto Exit;
     }
diff --git a/src/sfnt/ttbdf.h b/src/sfnt/ttbdf.h
index 595aeb76c..0d7a0acec 100644
--- a/src/sfnt/ttbdf.h
+++ b/src/sfnt/ttbdf.h
@@ -34,7 +34,7 @@ FT_BEGIN_HEADER
 
 
   FT_LOCAL( FT_Error )
-  tt_face_find_bdf_prop( TT_Face           face,
+  tt_face_find_bdf_prop( FT_Face           face,
                          const char*       property_name,
                          BDF_PropertyRec  *aprop );