* src/cff/*: 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.

4 files changed, 173 insertions, 155 deletions

diff --git a/src/cff/cffdrivr.c b/src/cff/cffdrivr.c
index 6d96e4abe..3d08f8d5b 100644
--- a/src/cff/cffdrivr.c
+++ b/src/cff/cffdrivr.c
@@ -108,20 +108,20 @@
    *   They can be implemented by format-specific interfaces.
    */
   FT_CALLBACK_DEF( FT_Error )
-  cff_get_kerning( FT_Face     ttface,          /* TT_Face */
+  cff_get_kerning( FT_Face     face,          /* CFF_Face */
                    FT_UInt     left_glyph,
                    FT_UInt     right_glyph,
                    FT_Vector*  kerning )
   {
-    TT_Face       face = (TT_Face)ttface;
-    SFNT_Service  sfnt = (SFNT_Service)face->sfnt;
+    CFF_Face      cffface = (CFF_Face)face;
+    SFNT_Service  sfnt    = (SFNT_Service)cffface->sfnt;
 
 
     kerning->x = 0;
     kerning->y = 0;
 
     if ( sfnt )
-      kerning->x = sfnt->get_kerning( face, left_glyph, right_glyph );
+      kerning->x = sfnt->get_kerning( cffface, left_glyph, right_glyph );
 
     return FT_Err_Ok;
   }
@@ -158,38 +158,38 @@
    *   FreeType error code.  0 means success.
    */
   FT_CALLBACK_DEF( FT_Error )
-  cff_glyph_load( FT_GlyphSlot  cffslot,      /* CFF_GlyphSlot */
-                  FT_Size       cffsize,      /* CFF_Size      */
+  cff_glyph_load( FT_GlyphSlot  slot,        /* CFF_GlyphSlot */
+                  FT_Size       size,        /* CFF_Size      */
                   FT_UInt       glyph_index,
                   FT_Int32      load_flags )
   {
     FT_Error       error;
-    CFF_GlyphSlot  slot = (CFF_GlyphSlot)cffslot;
-    CFF_Size       size = (CFF_Size)cffsize;
+    CFF_GlyphSlot  cffslot = (CFF_GlyphSlot)slot;
+    CFF_Size       cffsize = (CFF_Size)size;
 
 
-    if ( !slot )
+    if ( !cffslot )
       return FT_THROW( Invalid_Slot_Handle );
 
     FT_TRACE1(( "cff_glyph_load: glyph index %d\n", glyph_index ));
 
     /* check whether we want a scaled outline or bitmap */
-    if ( !size )
+    if ( !cffsize )
       load_flags |= FT_LOAD_NO_SCALE | FT_LOAD_NO_HINTING;
 
     /* reset the size object if necessary */
     if ( load_flags & FT_LOAD_NO_SCALE )
       size = NULL;
 
-    if ( size )
+    if ( cffsize )
     {
       /* these two objects must have the same parent */
-      if ( cffsize->face != cffslot->face )
+      if ( size->face != slot->face )
         return FT_THROW( Invalid_Face_Handle );
     }
 
     /* now load the glyph outline if necessary */
-    error = cff_slot_load( slot, size, glyph_index, load_flags );
+    error = cff_slot_load( cffslot, cffsize, glyph_index, load_flags );
 
     /* force drop-out mode to 2 - irrelevant now */
     /* slot->outline.dropout_mode = 2; */
@@ -216,7 +216,7 @@
       /* it is no longer necessary that those values are identical to   */
       /* the values in the `CFF' table                                  */
 
-      TT_Face   ttface = (TT_Face)face;
+      CFF_Face  cffface = (CFF_Face)face;
       FT_Short  dummy;
 
 
@@ -225,7 +225,7 @@
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
         /* no fast retrieval for blended MM fonts without VVAR table */
         if ( ( FT_IS_NAMED_INSTANCE( face ) || FT_IS_VARIATION( face ) ) &&
-             !( ttface->variation_support & TT_FACE_FLAG_VAR_VADVANCE )  )
+             !( cffface->variation_support & TT_FACE_FLAG_VAR_VADVANCE ) )
           return FT_THROW( Unimplemented_Feature );
 #endif
 
@@ -233,7 +233,7 @@
         /* otherwise we extract the info from the CFF glyphstrings  */
         /* (instead of synthesizing a global value using the `OS/2' */
         /* table)                                                   */
-        if ( !ttface->vertical_info )
+        if ( !cffface->vertical_info )
           goto Missing_Table;
 
         for ( nn = 0; nn < count; nn++ )
@@ -241,11 +241,11 @@
           FT_UShort  ah;
 
 
-          ( (SFNT_Service)ttface->sfnt )->get_metrics( ttface,
-                                                       1,
-                                                       start + nn,
-                                                       &dummy,
-                                                       &ah );
+          ( (SFNT_Service)cffface->sfnt )->get_metrics( cffface,
+                                                        1,
+                                                        start + nn,
+                                                        &dummy,
+                                                        &ah );
 
           FT_TRACE5(( "  idx %d: advance height %d font unit%s\n",
                       start + nn,
@@ -259,12 +259,12 @@
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
         /* no fast retrieval for blended MM fonts without HVAR table */
         if ( ( FT_IS_NAMED_INSTANCE( face ) || FT_IS_VARIATION( face ) ) &&
-             !( ttface->variation_support & TT_FACE_FLAG_VAR_HADVANCE )  )
+             !( cffface->variation_support & TT_FACE_FLAG_VAR_HADVANCE ) )
           return FT_THROW( Unimplemented_Feature );
 #endif
 
         /* check whether we have data from the `hmtx' table at all */
-        if ( !ttface->horizontal.number_Of_HMetrics )
+        if ( !cffface->horizontal.number_Of_HMetrics )
           goto Missing_Table;
 
         for ( nn = 0; nn < count; nn++ )
@@ -272,11 +272,11 @@
           FT_UShort  aw;
 
 
-          ( (SFNT_Service)ttface->sfnt )->get_metrics( ttface,
-                                                       0,
-                                                       start + nn,
-                                                       &dummy,
-                                                       &aw );
+          ( (SFNT_Service)cffface->sfnt )->get_metrics( cffface,
+                                                        0,
+                                                        start + nn,
+                                                        &dummy,
+                                                        &aw );
 
           FT_TRACE5(( "  idx %d: advance width %d font unit%s\n",
                       start + nn,
@@ -312,13 +312,14 @@
    *
    */
 
-  static FT_Error
-  cff_get_glyph_name( CFF_Face    face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_glyph_name( FT_Face     face,        /* CFF_Face */
                       FT_UInt     glyph_index,
                       FT_Pointer  buffer,
                       FT_UInt     buffer_max )
   {
-    CFF_Font    font   = (CFF_Font)face->extra.data;
+    CFF_Face    cffface = (CFF_Face)face;
+    CFF_Font    font    = (CFF_Font)cffface->extra.data;
     FT_String*  gname;
     FT_UShort   sid;
     FT_Error    error;
@@ -338,10 +339,7 @@
 
 
       if ( service && service->get_name )
-        return service->get_name( FT_FACE( face ),
-                                  glyph_index,
-                                  buffer,
-                                  buffer_max );
+        return service->get_name( face, glyph_index, buffer, buffer_max );
       else
       {
         FT_ERROR(( "cff_get_glyph_name:"
@@ -366,7 +364,7 @@
     /* first, locate the sid in the charset table */
     sid = font->charset.sids[glyph_index];
 
-    /* now, lookup the name itself */
+    /* now, look up the name itself */
     gname = cff_index_get_sid_string( font, sid );
 
     if ( gname )
@@ -379,21 +377,19 @@
   }
 
 
-  static FT_UInt
-  cff_get_name_index( CFF_Face          face,
+  FT_CALLBACK_DEF( FT_UInt )
+  cff_get_name_index( FT_Face           face,        /* CFF_Face */
                       const FT_String*  glyph_name )
   {
-    CFF_Font            cff;
-    CFF_Charset         charset;
+    CFF_Face            cffface = (CFF_Face)face;
+    CFF_Font            cff     = (CFF_Font)cffface->extra.data;
+    CFF_Charset         charset = &cff->charset;
     FT_Service_PsCMaps  psnames;
     FT_String*          name;
     FT_UShort           sid;
     FT_UInt             i;
 
 
-    cff     = (CFF_FontRec *)face->extra.data;
-    charset = &cff->charset;
-
     /* CFF2 table does not have glyph names; */
     /* we need to use `post' table method    */
     if ( cff->version_major == 2 )
@@ -408,7 +404,7 @@
 
 
       if ( service && service->name_index )
-        return service->name_index( FT_FACE( face ), glyph_name );
+        return service->name_index( face, glyph_name );
       else
       {
         FT_ERROR(( "cff_get_name_index:"
@@ -456,22 +452,23 @@
    *
    */
 
-  static FT_Int
+  FT_CALLBACK_DEF( FT_Int )
   cff_ps_has_glyph_names( FT_Face  face )
   {
     return ( face->face_flags & FT_FACE_FLAG_GLYPH_NAMES ) > 0;
   }
 
 
-  static FT_Error
-  cff_ps_get_font_info( CFF_Face         face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_ps_get_font_info( FT_Face          face,        /* CFF_Face */
                         PS_FontInfoRec*  afont_info )
   {
-    CFF_Font  cff   = (CFF_Font)face->extra.data;
-    FT_Error  error = FT_Err_Ok;
+    CFF_Face  cffface = (CFF_Face)face;
+    CFF_Font  cff     = (CFF_Font)cffface->extra.data;
+    FT_Error  error   = FT_Err_Ok;
 
 
-    if ( face->is_cff2 )
+    if ( cffface->is_cff2 )
     {
       error = FT_THROW( Invalid_Argument );
       goto Fail;
@@ -480,7 +477,7 @@
     if ( cff && !cff->font_info )
     {
       CFF_FontRecDict  dict      = &cff->top_font.font_dict;
-      FT_Memory        memory    = face->root.memory;
+      FT_Memory        memory    = FT_FACE_MEMORY( face );
       PS_FontInfoRec*  font_info = NULL;
 
 
@@ -513,18 +510,19 @@
   }
 
 
-  static FT_Error
-  cff_ps_get_font_extra( CFF_Face          face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_ps_get_font_extra( FT_Face           face,         /* CFF_Face */
                          PS_FontExtraRec*  afont_extra )
   {
-    CFF_Font  cff   = (CFF_Font)face->extra.data;
-    FT_Error  error = FT_Err_Ok;
+    CFF_Face  cffface = (CFF_Face)face;
+    CFF_Font  cff     = (CFF_Font)cffface->extra.data;
+    FT_Error  error   = FT_Err_Ok;
 
 
     if ( cff && !cff->font_extra )
     {
       CFF_FontRecDict   dict       = &cff->top_font.font_dict;
-      FT_Memory         memory     = face->root.memory;
+      FT_Memory         memory     = FT_FACE_MEMORY( face );
       PS_FontExtraRec*  font_extra = NULL;
       FT_String*        embedded_postscript;
 
@@ -609,17 +607,18 @@
    *
    */
 
-  static const char*
-  cff_get_ps_name( CFF_Face  face )
+  FT_CALLBACK_DEF( const char* )
+  cff_get_ps_name( FT_Face  face )    /* CFF_Face */
   {
-    CFF_Font      cff  = (CFF_Font)face->extra.data;
-    SFNT_Service  sfnt = (SFNT_Service)face->sfnt;
+    CFF_Face      cffface = (CFF_Face)face;
+    CFF_Font      cff     = (CFF_Font)cffface->extra.data;
+    SFNT_Service  sfnt    = (SFNT_Service)cffface->sfnt;
 
 
     /* following the OpenType specification 1.7, we return the name stored */
     /* in the `name' table for a CFF wrapped into an SFNT container        */
 
-    if ( FT_IS_SFNT( FT_FACE( face ) ) && sfnt )
+    if ( FT_IS_SFNT( face ) && sfnt )
     {
       FT_Library             library     = FT_FACE_LIBRARY( face );
       FT_Module              sfnt_module = FT_Get_Module( library, "sfnt" );
@@ -631,7 +630,7 @@
 
 
       if ( service && service->get_ps_font_name )
-        return service->get_ps_font_name( FT_FACE( face ) );
+        return service->get_ps_font_name( face );
     }
 
     return cff ? (const char*)cff->font_name : NULL;
@@ -655,7 +654,7 @@
    * Otherwise call the service function in the sfnt module.
    *
    */
-  static FT_Error
+  FT_CALLBACK_DEF( FT_Error )
   cff_get_cmap_info( FT_CharMap    charmap,
                      TT_CMapInfo  *cmap_info )
   {
@@ -697,14 +696,15 @@
    * CID INFO SERVICE
    *
    */
-  static FT_Error
-  cff_get_ros( CFF_Face      face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_ros( FT_Face       face,        /* FT_Face */
                const char*  *registry,
                const char*  *ordering,
                FT_Int       *supplement )
   {
-    FT_Error  error = FT_Err_Ok;
-    CFF_Font  cff   = (CFF_Font)face->extra.data;
+    FT_Error  error   = FT_Err_Ok;
+    CFF_Face  cffface = (CFF_Face)face;
+    CFF_Font  cff     = (CFF_Font)cffface->extra.data;
 
 
     if ( cff )
@@ -754,12 +754,13 @@
   }
 
 
-  static FT_Error
-  cff_get_is_cid( CFF_Face  face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_is_cid( FT_Face   face,    /* CFF_Face */
                   FT_Bool  *is_cid )
   {
-    FT_Error  error = FT_Err_Ok;
-    CFF_Font  cff   = (CFF_Font)face->extra.data;
+    FT_Error  error   = FT_Err_Ok;
+    CFF_Face  cffface = (CFF_Face)face;
+    CFF_Font  cff     = (CFF_Font)cffface->extra.data;
 
 
     *is_cid = 0;
@@ -777,17 +778,16 @@
   }
 
 
-  static FT_Error
-  cff_get_cid_from_glyph_index( CFF_Face  face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_cid_from_glyph_index( FT_Face   face,        /* CFF_Face */
                                 FT_UInt   glyph_index,
                                 FT_UInt  *cid )
   {
-    FT_Error  error = FT_Err_Ok;
-    CFF_Font  cff;
+    FT_Error  error   = FT_Err_Ok;
+    CFF_Face  cffface = (CFF_Face)face;
+    CFF_Font  cff     = (CFF_Font)cffface->extra.data;
 
 
-    cff = (CFF_Font)face->extra.data;
-
     if ( cff )
     {
       FT_UInt          c;
@@ -848,181 +848,195 @@
    *
    */
 
-  static FT_Error
-  cff_set_mm_blend( CFF_Face   face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_set_mm_blend( FT_Face    face,        /* CFF_Face */
                     FT_UInt    num_coords,
                     FT_Fixed*  coords )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->set_mm_blend( FT_FACE( face ), num_coords, coords );
+    return mm->set_mm_blend( face, num_coords, coords );
   }
 
 
-  static FT_Error
-  cff_get_mm_blend( CFF_Face   face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_mm_blend( FT_Face    face,       /* CFF_Face */
                     FT_UInt    num_coords,
                     FT_Fixed*  coords )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_mm_blend( FT_FACE( face ), num_coords, coords );
+    return mm->get_mm_blend( face, num_coords, coords );
   }
 
 
-  static FT_Error
-  cff_set_mm_weightvector( CFF_Face   face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_set_mm_weightvector( FT_Face    face,          /* CFF_Face */
                            FT_UInt    len,
                            FT_Fixed*  weightvector )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->set_mm_weightvector( FT_FACE( face ), len, weightvector );
+    return mm->set_mm_weightvector( face, len, weightvector );
   }
 
 
-  static FT_Error
-  cff_get_mm_weightvector( CFF_Face   face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_mm_weightvector( FT_Face    face,          /* CFF_Face */
                            FT_UInt*   len,
                            FT_Fixed*  weightvector )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_mm_weightvector( FT_FACE( face ), len, weightvector );
+    return mm->get_mm_weightvector( face, len, weightvector );
   }
 
 
-  static void
-  cff_construct_ps_name( CFF_Face  face )
+  FT_CALLBACK_DEF( void )
+  cff_construct_ps_name( FT_Face  face )  /* CFF_Face */
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    mm->construct_ps_name( FT_FACE( face ) );
+    mm->construct_ps_name( face );
   }
 
 
-  static FT_Error
-  cff_get_mm_var( CFF_Face     face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_mm_var( FT_Face      face,    /* CFF_Face */
                   FT_MM_Var*  *master )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_mm_var( FT_FACE( face ), master );
+    return mm->get_mm_var( face, master );
   }
 
 
-  static FT_Error
-  cff_set_var_design( CFF_Face   face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_set_var_design( FT_Face    face,       /* CFF_Face */
                       FT_UInt    num_coords,
                       FT_Fixed*  coords )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->set_var_design( FT_FACE( face ), num_coords, coords );
+    return mm->set_var_design( face, num_coords, coords );
   }
 
 
-  static FT_Error
-  cff_get_var_design( CFF_Face   face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_var_design( FT_Face    face,       /* CFF_Face */
                       FT_UInt    num_coords,
                       FT_Fixed*  coords )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_var_design( FT_FACE( face ), num_coords, coords );
+    return mm->get_var_design( face, num_coords, coords );
   }
 
 
-  static FT_Error
-  cff_set_named_instance( CFF_Face  face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_set_named_instance( FT_Face   face,            /* CFF_Face */
                           FT_UInt   instance_index )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->set_named_instance( FT_FACE( face ), instance_index );
+    return mm->set_named_instance( face, instance_index );
   }
 
 
-  static FT_Error
-  cff_get_default_named_instance( CFF_Face  face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_get_default_named_instance( FT_Face   face,            /* CFF_Face */
                                   FT_UInt  *instance_index )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_default_named_instance( FT_FACE( face ), instance_index );
+    return mm->get_default_named_instance( face, instance_index );
   }
 
 
-  static FT_Error
-  cff_load_item_variation_store( CFF_Face         face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_load_item_variation_store( FT_Face          face,       /* CFF_Face */
                                  FT_ULong         offset,
                                  GX_ItemVarStore  itemStore )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->load_item_var_store( FT_FACE(face), offset, itemStore );
+    return mm->load_item_var_store( face, offset, itemStore );
   }
 
 
-  static FT_Error
-  cff_load_delta_set_index_mapping( CFF_Face           face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_load_delta_set_index_mapping( FT_Face            face,   /* CFF_Face */
                                     FT_ULong           offset,
                                     GX_DeltaSetIdxMap  map,
                                     GX_ItemVarStore    itemStore,
                                     FT_ULong           table_len )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->load_delta_set_idx_map( FT_FACE( face ), offset, map,
+    return mm->load_delta_set_idx_map( face, offset, map,
                                        itemStore, table_len );
   }
 
 
-  static FT_Int
-  cff_get_item_delta( CFF_Face         face,
+  FT_CALLBACK_DEF( FT_Int )
+  cff_get_item_delta( FT_Face          face,        /* CFF_Face */
                       GX_ItemVarStore  itemStore,
                       FT_UInt          outerIndex,
                       FT_UInt          innerIndex )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_item_delta( FT_FACE( face ), itemStore,
-                               outerIndex, innerIndex );
+    return mm->get_item_delta( face, itemStore, outerIndex, innerIndex );
   }
 
 
-  static void
-  cff_done_item_variation_store( CFF_Face          face,
+  FT_CALLBACK_DEF( void )
+  cff_done_item_variation_store( FT_Face          face,       /* CFF_Face */
                                  GX_ItemVarStore  itemStore )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    mm->done_item_var_store( FT_FACE( face ), itemStore );
+    mm->done_item_var_store( face, itemStore );
   }
 
 
-  static void
-  cff_done_delta_set_index_map( CFF_Face           face,
+  FT_CALLBACK_DEF( void )
+  cff_done_delta_set_index_map( FT_Face            face,       /* CFF_Face */
                                 GX_DeltaSetIdxMap  deltaSetIdxMap )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    mm->done_delta_set_idx_map( FT_FACE ( face ), deltaSetIdxMap );
+    mm->done_delta_set_idx_map( face, deltaSetIdxMap );
   }
 
 
@@ -1077,27 +1091,29 @@
    *
    */
 
-  static FT_Error
-  cff_hadvance_adjust( CFF_Face  face,
+  FT_CALLBACK_DEF( FT_Error )
+  cff_hadvance_adjust( FT_Face   face,    /* CFF_Face */
                        FT_UInt   gindex,
                        FT_Int   *avalue )
   {
+    CFF_Face  cffface = (CFF_Face)face;
     FT_Service_MetricsVariations
-      var = (FT_Service_MetricsVariations)face->tt_var;
+              var     = (FT_Service_MetricsVariations)cffface->tt_var;
 
 
-    return var->hadvance_adjust( FT_FACE( face ), gindex, avalue );
+    return var->hadvance_adjust( face, gindex, avalue );
   }
 
 
-  static void
-  cff_metrics_adjust( CFF_Face  face )
+  FT_CALLBACK_DEF( void )
+  cff_metrics_adjust( FT_Face  face )    /* CFF_Face */
   {
+    CFF_Face  cffface = (CFF_Face)face;
     FT_Service_MetricsVariations
-      var = (FT_Service_MetricsVariations)face->tt_var;
+              var     = (FT_Service_MetricsVariations)cffface->tt_var;
 
 
-    var->metrics_adjust( FT_FACE( face ) );
+    var->metrics_adjust( face );
   }
 
 
diff --git a/src/cff/cffload.c b/src/cff/cffload.c
index a090111e3..f96002ec0 100644
--- a/src/cff/cffload.c
+++ b/src/cff/cffload.c
@@ -1589,16 +1589,17 @@
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
 
   FT_LOCAL_DEF( FT_Error )
-  cff_get_var_blend( CFF_Face     face,
+  cff_get_var_blend( FT_Face      face,             /* CFF_Face */
                      FT_UInt     *num_coords,
                      FT_Fixed*   *coords,
                      FT_Fixed*   *normalizedcoords,
                      FT_MM_Var*  *mm_var )
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
-    return mm->get_var_blend( FT_FACE( face ),
+    return mm->get_var_blend( face,
                               num_coords,
                               coords,
                               normalizedcoords,
@@ -1607,13 +1608,14 @@
 
 
   FT_LOCAL_DEF( void )
-  cff_done_blend( CFF_Face  face )
+  cff_done_blend( FT_Face  face )    /* CFF_Face */
   {
-    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+    CFF_Face                 cffface = (CFF_Face)face;
+    FT_Service_MultiMasters  mm      = (FT_Service_MultiMasters)cffface->mm;
 
 
     if ( mm )
-      mm->done_blend( FT_FACE( face ) );
+      mm->done_blend( face );
   }
 
 #endif /* TT_CONFIG_OPTION_GX_VAR_SUPPORT */
diff --git a/src/cff/cffload.h b/src/cff/cffload.h
index 5a41cdebc..b5286b0c8 100644
--- a/src/cff/cffload.h
+++ b/src/cff/cffload.h
@@ -105,14 +105,14 @@ FT_BEGIN_HEADER
 
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
   FT_LOCAL( FT_Error )
-  cff_get_var_blend( CFF_Face     face,
+  cff_get_var_blend( FT_Face      face,
                      FT_UInt     *num_coords,
                      FT_Fixed*   *coords,
                      FT_Fixed*   *normalizedcoords,
                      FT_MM_Var*  *mm_var );
 
   FT_LOCAL( void )
-  cff_done_blend( CFF_Face  face );
+  cff_done_blend( FT_Face  face );
 #endif
 
 
diff --git a/src/cff/cffobjs.c b/src/cff/cffobjs.c
index 1f24f3d91..6d08620c4 100644
--- a/src/cff/cffobjs.c
+++ b/src/cff/cffobjs.c
@@ -1150,7 +1150,7 @@
     }
 
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
-    cff_done_blend( face );
+    cff_done_blend( cffface );
     face->blend = NULL;
 #endif
   }