[ot-font] Implement hb_ot_get_glyph_name

Turns out we already have support for “post” table, it just needed to be
activated and put in use.

src/hb-ot-font.cc

@@ -38,7 +38,7 @@
 #include "hb-ot-hmtx-table.hh"
 #include "hb-ot-os2-table.hh"
 #include "hb-ot-var-hvar-table.hh"
-//#include "hb-ot-post-table.hh"
+#include "hb-ot-post-table.hh"
 
 
 struct hb_ot_face_metrics_accelerator_t
@@ -301,6 +301,34 @@ struct hb_ot_face_cbdt_accelerator_t
   }
 };
 
+struct hb_ot_face_post_accelerator_t
+{
+  hb_blob_t *post_blob;
+  unsigned int post_len;
+  const OT::post *post;
+
+  inline void init (hb_face_t *face)
+  {
+    this->post_blob = OT::Sanitizer<OT::post>::sanitize (face->reference_table (HB_OT_TAG_post));
+    this->post = OT::Sanitizer<OT::post>::lock_instance (this->post_blob);
+    this->post_len = hb_blob_get_length (this->post_blob);
+  }
+
+  inline void fini (void)
+  {
+    hb_blob_destroy (this->post_blob);
+  }
+
+  inline bool get_glyph_name (hb_codepoint_t glyph,
+                              char *name, unsigned int size) const
+  {
+    if (unlikely (!name) || unlikely(!size))
+      return false;
+
+    return this->post->get_glyph_name (glyph, name, size, this->post_len);
+  }
+};
+
 typedef bool (*hb_cmap_get_glyph_func_t) (const void *obj,
 					  hb_codepoint_t codepoint,
 					  hb_codepoint_t *glyph);
@@ -436,6 +464,7 @@ struct hb_ot_font_t
   hb_ot_face_metrics_accelerator_t v_metrics;
   OT::hb_lazy_loader_t<hb_ot_face_glyf_accelerator_t> glyf;
   OT::hb_lazy_loader_t<hb_ot_face_cbdt_accelerator_t> cbdt;
+  OT::hb_lazy_loader_t<hb_ot_face_post_accelerator_t> post;
 };
 
 
@@ -453,6 +482,7 @@ _hb_ot_font_create (hb_face_t *face)
 			   ot_font->h_metrics.ascender - ot_font->h_metrics.descender); /* TODO Can we do this lazily? */
   ot_font->glyf.init (face);
   ot_font->cbdt.init (face);
+  ot_font->post.init (face);
 
   return ot_font;
 }
@@ -467,6 +497,7 @@ _hb_ot_font_destroy (void *data)
   ot_font->v_metrics.fini ();
   ot_font->glyf.fini ();
   ot_font->cbdt.fini ();
+  ot_font->post.fini ();
 
   free (ot_font);
 }
@@ -535,6 +566,17 @@ hb_ot_get_glyph_extents (hb_font_t *font HB_UNUSED,
   return ret;
 }
 
+static hb_bool_t
+hb_ot_get_glyph_name (hb_font_t *font HB_UNUSED,
+                      void *font_data,
+                      hb_codepoint_t glyph,
+                      char *name, unsigned int size,
+                      void *user_data HB_UNUSED)
+{
+  const hb_ot_font_t *ot_font = (const hb_ot_font_t *) font_data;
+  return ot_font->post->get_glyph_name (glyph, name, size);
+}
+
 static hb_bool_t
 hb_ot_get_font_h_extents (hb_font_t *font HB_UNUSED,
 			  void *font_data,
@@ -595,7 +637,7 @@ retry:
     //hb_font_funcs_set_glyph_v_kerning_func (funcs, hb_ot_get_glyph_v_kerning, nullptr, nullptr);
     hb_font_funcs_set_glyph_extents_func (funcs, hb_ot_get_glyph_extents, nullptr, nullptr);
     //hb_font_funcs_set_glyph_contour_point_func (funcs, hb_ot_get_glyph_contour_point, nullptr, nullptr); TODO
-    //hb_font_funcs_set_glyph_name_func (funcs, hb_ot_get_glyph_name, nullptr, nullptr); TODO
+    hb_font_funcs_set_glyph_name_func (funcs, hb_ot_get_glyph_name, nullptr, nullptr);
     //hb_font_funcs_set_glyph_from_name_func (funcs, hb_ot_get_glyph_from_name, nullptr, nullptr); TODO
 
     hb_font_funcs_make_immutable (funcs);

src/hb-ot-post-table.hh

@@ -29,6 +29,48 @@
 
 #include "hb-open-type-private.hh"
 
+#define NUM_FORMAT1_NAMES 258
+
+static const char* const format1_names[NUM_FORMAT1_NAMES] =
+{
+  ".notdef", ".null", "nonmarkingreturn", "space", "exclam", "quotedbl",
+  "numbersign", "dollar", "percent", "ampersand", "quotesingle", "parenleft",
+  "parenright", "asterisk", "plus", "comma", "hyphen", "period", "slash",
+  "zero", "one", "two", "three", "four", "five", "six", "seven", "eight",
+  "nine", "colon", "semicolon", "less", "equal", "greater", "question", "at",
+  "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O",
+  "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "bracketleft",
+  "backslash", "bracketright", "asciicircum", "underscore", "grave", "a", "b",
+  "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q",
+  "r", "s", "t", "u", "v", "w", "x", "y", "z", "braceleft", "bar",
+  "braceright", "asciitilde", "Adieresis", "Aring", "Ccedilla", "Eacute",
+  "Ntilde", "Odieresis", "Udieresis", "aacute", "agrave", "acircumflex",
+  "adieresis", "atilde", "aring", "ccedilla", "eacute", "egrave",
+  "ecircumflex", "edieresis", "iacute", "igrave", "icircumflex", "idieresis",
+  "ntilde", "oacute", "ograve", "ocircumflex", "odieresis", "otilde", "uacute",
+  "ugrave", "ucircumflex", "udieresis", "dagger", "degree", "cent", "sterling",
+  "section", "bullet", "paragraph", "germandbls", "registered", "copyright",
+  "trademark", "acute", "dieresis", "notequal", "AE", "Oslash", "infinity",
+  "plusminus", "lessequal", "greaterequal", "yen", "mu", "partialdiff",
+  "summation", "product", "pi", "integral", "ordfeminine", "ordmasculine",
+  "Omega", "ae", "oslash", "questiondown", "exclamdown", "logicalnot",
+  "radical", "florin", "approxequal", "Delta", "guillemotleft",
+  "guillemotright", "ellipsis", "nonbreakingspace", "Agrave", "Atilde",
+  "Otilde", "OE", "oe", "endash", "emdash", "quotedblleft", "quotedblright",
+  "quoteleft", "quoteright", "divide", "lozenge", "ydieresis", "Ydieresis",
+  "fraction", "currency", "guilsinglleft", "guilsinglright", "fi", "fl",
+  "daggerdbl", "periodcentered", "quotesinglbase", "quotedblbase",
+  "perthousand", "Acircumflex", "Ecircumflex", "Aacute", "Edieresis", "Egrave",
+  "Iacute", "Icircumflex", "Idieresis", "Igrave", "Oacute", "Ocircumflex",
+  "apple", "Ograve", "Uacute", "Ucircumflex", "Ugrave", "dotlessi",
+  "circumflex", "tilde", "macron", "breve", "dotaccent", "ring", "cedilla",
+  "hungarumlaut", "ogonek", "caron", "Lslash", "lslash", "Scaron", "scaron",
+  "Zcaron", "zcaron", "brokenbar", "Eth", "eth", "Yacute", "yacute", "Thorn",
+  "thorn", "minus", "multiply", "onesuperior", "twosuperior", "threesuperior",
+  "onehalf", "onequarter", "threequarters", "franc", "Gbreve", "gbreve",
+  "Idotaccent", "Scedilla", "scedilla", "Cacute", "cacute", "Ccaron", "ccaron",
+  "dcroat",
+};
 
 namespace OT {
 
@@ -77,6 +119,60 @@ struct post
     return_trace (true);
   }
 
+  inline bool get_glyph_name (hb_codepoint_t glyph,
+                              char *buffer, unsigned int buffer_length,
+                              unsigned int blob_len) const
+  {
+    if (version.to_int () == 0x00010000)
+    {
+      if (glyph >= NUM_FORMAT1_NAMES)
+        return false;
+
+      strncpy(buffer, format1_names[glyph], buffer_length);
+      buffer[buffer_length] = '\0';
+      return true;
+    }
+
+    if (version.to_int () == 0x00020000)
+    {
+      const postV2Tail &v2 = StructAfter<postV2Tail>(*this);
+
+      if (glyph >= v2.numberOfGlyphs)
+        return false;
+
+      unsigned int index = v2.glyphNameIndex[glyph];
+      if (index >= NUM_FORMAT1_NAMES)
+      {
+        unsigned int offset = min_size + v2.min_size + 2 * v2.numberOfGlyphs;
+        char* data = (char*) this + offset;
+        for (unsigned int i = 0; data < (char*) this + blob_len; i++)
+        {
+          unsigned int name_length = data[0];
+          data++;
+          if (i == index - NUM_FORMAT1_NAMES)
+          {
+            unsigned int remaining = (char*) this + blob_len - data;
+            name_length = MIN (name_length, buffer_length);
+            name_length = MIN (name_length, remaining);
+            memcpy (buffer, data, name_length);
+            buffer[name_length] = '\0';
+            return true;
+          }
+          data += name_length;
+        }
+        return false;
+      }
+      else
+      {
+        strncpy(buffer, format1_names[index], buffer_length);
+        buffer[buffer_length] = '\0';
+        return true;
+      }
+    }
+
+    return false;
+  }
+
   public:
   FixedVersion<>version;		/* 0x00010000 for version 1.0
 					 * 0x00020000 for version 2.0

test/shaping/tests/fallback-positioning.tests

@@ -1,2 +1,2 @@
 fonts/sha1sum/7ef276fc886ea502a03b9b0e5c8b547d5dc2b61c.ttf:--font-funcs=ft:U+0078,U+0301,U+0058,U+0301:[x=0+1030|acutecomb=0@-45,-32+0|X=2+1295|acutecomb=2@-171,310+0]
-fonts/sha1sum/7ef276fc886ea502a03b9b0e5c8b547d5dc2b61c.ttf:--font-funcs=ot:U+0078,U+0301,U+0058,U+0301:[gid2=0+1030|gid4=0@-21,-27+0|gid1=2+1295|gid4=2@-147,321+0]
+fonts/sha1sum/7ef276fc886ea502a03b9b0e5c8b547d5dc2b61c.ttf:--font-funcs=ot:U+0078,U+0301,U+0058,U+0301:[x=0+1030|acutecomb=0@-21,-27+0|X=2+1295|acutecomb=2@-147,321+0]

test/shaping/tests/indic-syllable.tests

@@ -1,7 +1,7 @@
 fonts/sha1sum/54674a3111d209fb6be0ed31745314b7a8d2c244.ttf::U+0BA4,U+0BCD,U+00B3:[taprehalftamil=0+1509|uni00B3=2+674]
 fonts/sha1sum/3d0b77a2360aa6faa1385aaa510509ab70dfbeff.ttf::U+0CF1:[gid1=0+1129]
 fonts/sha1sum/3d0b77a2360aa6faa1385aaa510509ab70dfbeff.ttf::U+0CF2:[gid2=0+1539]
-fonts/sha1sum/87f85d17d26f1fe9ad28d7365101958edaefb967.ttf:--font-funcs=ot:U+0980,U+0981:[gid1=0+520|gid2=0+0]
+fonts/sha1sum/87f85d17d26f1fe9ad28d7365101958edaefb967.ttf:--font-funcs=ot:U+0980,U+0981:[anjibeng=0+520|candrabindubeng=0+0]
 fonts/sha1sum/85fe0be440c64ac77699e21c2f1bd933a919167e.ttf::U+0A15,U+0A51,U+0A47:[kaguru=0+1273|udaatguru=0@75,0+0|eematraguru=0@-40,0+0]
 fonts/sha1sum/1735326da89f0818cd8c51a0600e9789812c0f94.ttf::U+0A51:[uni25CC=0+1044|udaatguru=0+0]
 fonts/sha1sum/1735326da89f0818cd8c51a0600e9789812c0f94.ttf::U+25CC,U+0A51:[uni25CC=0+1044|udaatguru=0+0]

test/shaping/tests/use.tests

@@ -1,4 +1,4 @@
 fonts/sha1sum/fbb6c84c9e1fe0c39e152fbe845e51fd81f6748e.ttf::U+1B1B,U+1B44,U+1B13,U+1B3E:[gid3=0+990|gid7=0+2473|gid5=0@-293,-400+0]
 fonts/sha1sum/4cce528e99f600ed9c25a2b69e32eb94a03b4ae8.ttf::U+1A48,U+1A58,U+1A25,U+1A48,U+1A58,U+1A25,U+1A6E,U+1A63:[uni1A48=0+1212|uni1A25=0+1912|uni1A58=0+0|uni1A48=3+1212|uni1A6E=3+0|uni1A25=3+1912|uni1A58=3+0|uni1A63=3+1212]
 fonts/sha1sum/f518eb6f6b5eec2946c9fbbbde44e45d46f5e2ac.ttf::U+1A48,U+1A58,U+1A25,U+1A48,U+1A58,U+1A25,U+1A6E,U+1A63:[uni1A48=0+1212|uni1A25=0+1912|uni1A58=0+0|uni1A48=3+1212|uni1A6E=3+1211|uni1A25=3+1912|uni1A58=3+0|uni1A63=3+1212]
-fonts/sha1sum/6ff0fbead4462d9f229167b4e6839eceb8465058.ttf:--font-funcs=ot:U+11103,U+11128:[gid1=0+837|gid2=0+0]
+fonts/sha1sum/6ff0fbead4462d9f229167b4e6839eceb8465058.ttf:--font-funcs=ot:U+11103,U+11128:[u11103=0+837|u11128=0+0]