add ops & methods to hb_bimap_t making it more like hb_map_t

moved has () to hb_bimap_t from hb_inc_bimap_t
moved identity () to hb_inc_bimap_t
removed forward()

src/hb-bimap.hh

@@ -47,9 +47,13 @@ struct hb_bimap_t
     back_map.fini ();
   }
 
-  /* returns HB_MAP_VALUE_INVALID if unmapped */
-  hb_codepoint_t forward (hb_codepoint_t lhs) const { return forw_map[lhs]; }
-  hb_codepoint_t backward (hb_codepoint_t rhs) const { return back_map[rhs]; }
+  void reset ()
+  {
+    forw_map.reset ();
+    back_map.reset ();
+  }
+
+  bool in_error () const { return forw_map.in_error () || back_map.in_error (); }
 
   void set (hb_codepoint_t lhs, hb_codepoint_t rhs)
   {
@@ -57,12 +61,16 @@ struct hb_bimap_t
     back_map.set (rhs, lhs);
   }
 
-  /* Create an identity map. */
-  bool identity (unsigned int size)
+  hb_codepoint_t get (hb_codepoint_t lhs) const { return forw_map.get (lhs); }
+  hb_codepoint_t backward (hb_codepoint_t rhs) const { return back_map[rhs]; }
+
+  hb_codepoint_t operator [] (hb_codepoint_t lhs) const { return get (lhs); }
+  bool has (hb_codepoint_t lhs, hb_codepoint_t *vp = nullptr) const { return forw_map.has (lhs, vp); }
+
+  void del (hb_codepoint_t lhs)
   {
-    clear ();
-    for (hb_codepoint_t i = 0; i < size; i++) set (i, i);
-    return forw_map.successful && back_map.successful;
+    back_map.del (get (lhs));
+    forw_map.del (lhs);
   }
 
   void clear ()
@@ -71,11 +79,7 @@ struct hb_bimap_t
     back_map.clear ();
   }
 
-  void reset ()
-  {
-    forw_map.reset ();
-    back_map.reset ();
-  }
+  bool is_empty () const { return get_population () == 0; }
 
   unsigned int get_population () const { return forw_map.get_population (); }
 
@@ -101,7 +105,13 @@ struct hb_inc_bimap_t : hb_bimap_t
     return rhs;
   }
 
-  bool has (hb_codepoint_t lhs) const { return forw_map.has (lhs); }
+  /* Create an identity map. */
+  bool identity (unsigned int size)
+  {
+    clear ();
+    for (hb_codepoint_t i = 0; i < size; i++) set (i, i);
+    return !in_error ();
+  }
 
   protected:
   static int cmp_id (const void* a, const void* b)

src/hb-ot-cff-common.hh

@@ -482,7 +482,7 @@ struct FDArray : CFFIndexOf<COUNT, FontDict>
       if (fdmap.has (i))
       {
 	FontDict *dict = c->start_embed<FontDict> ();
-	if (unlikely (!dict->serialize (c, fontDicts[i], opszr, privateInfos[fdmap.forward (i)])))
+	if (unlikely (!dict->serialize (c, fontDicts[i], opszr, privateInfos[fdmap[i]])))
 	  return_trace (false);
       }
     return_trace (true);

src/hb-ot-cff1-table.hh

@@ -611,7 +611,7 @@ struct CFF1StringIndex : CFF1Index
       return_trace (false);
     for (unsigned int i = 0; i < strings.count; i++)
     {
-      hb_codepoint_t  j = sidmap.forward (i);
+      hb_codepoint_t  j = sidmap[i];
       if (j != CFF_UNDEF_CODE)
 	bytesArray[j] = strings[i];
     }
@@ -630,7 +630,7 @@ struct CFF1StringIndex : CFF1Index
 
     unsigned int dataSize = 0;
     for (unsigned int i = 0; i < count; i++)
-      if (sidmap.forward (i) != CFF_UNDEF_CODE)
+      if (sidmap[i] != CFF_UNDEF_CODE)
 	dataSize += length_at (i);
 
     offSize_ = calcOffSize(dataSize);

src/hb-subset-cff-common.cc

@@ -114,7 +114,7 @@ hb_plan_subset_cff_fdselect (const hb_subset_plan_t *plan,
 
     /* update each font dict index stored as "code" in fdselect_ranges */
     for (unsigned int i = 0; i < fdselect_ranges.length; i++)
-      fdselect_ranges[i].code = fdmap.forward (fdselect_ranges[i].code);
+      fdselect_ranges[i].code = fdmap[fdselect_ranges[i].code];
   }
 
   /* determine which FDSelect format is most compact */

src/hb-subset-cff-common.hh

@@ -563,7 +563,7 @@ struct subr_remap_t : hb_inc_bimap_t
 
   int biased_num (unsigned int old_num) const
   {
-    hb_codepoint_t new_num = forward (old_num);
+    hb_codepoint_t new_num = get (old_num);
     return (int)new_num - bias;
   }
 
@@ -761,7 +761,7 @@ struct subr_subsetter_t
       return false;
     for (unsigned int old_num = 0; old_num < subrs.length; old_num++)
     {
-      hb_codepoint_t new_num = remap.forward (old_num);
+      hb_codepoint_t new_num = remap[old_num];
       if (new_num != CFF_UNDEF_CODE)
       {
 	if (unlikely (!encode_str (subrs[old_num], fd, buffArray[new_num])))

src/hb-subset-cff1.cc

@@ -54,7 +54,7 @@ struct remap_sid_t : hb_inc_bimap_t
     if (is_std_std (sid) || (sid == CFF_UNDEF_SID))
       return sid;
     else
-      return offset_sid (forward (unoffset_sid (sid)));
+      return offset_sid (get (unoffset_sid (sid)));
   }
 
   static const unsigned int num_std_strings = 391;
@@ -1038,7 +1038,7 @@ static inline bool _write_cff1 (const cff_subset_plan &plan,
     {
       PrivateDict  *pd = c.start_embed<PrivateDict> ();
       if (unlikely (pd == nullptr)) return false;
-      unsigned int priv_size = plan.fontdicts_mod[plan.fdmap.forward (i)].privateDictInfo.size;
+      unsigned int priv_size = plan.fontdicts_mod[plan.fdmap[i]].privateDictInfo.size;
       bool result;
       cff_private_dict_op_serializer_t privSzr (plan.desubroutinize, plan.drop_hints);
       /* N.B. local subrs immediately follows its corresponding private dict. i.e., subr offset == private dict size */

src/hb-subset-cff2.cc

@@ -542,7 +542,7 @@ static inline bool _write_cff2 (const cff2_subset_plan &plan,
     {
       PrivateDict  *pd = c.start_embed<PrivateDict> ();
       if (unlikely (pd == nullptr)) return false;
-      unsigned int priv_size = plan.privateDictInfos[plan.fdmap.forward (i)].size;
+      unsigned int priv_size = plan.privateDictInfos[plan.fdmap[i]].size;
       bool result;
       cff_private_dict_op_serializer_t privSzr (plan.desubroutinize, plan.drop_hints);
       /* N.B. local subrs immediately follows its corresponding private dict. i.e., subr offset == private dict size */