The Tor Browser: gfx/harfbuzz/src/hb-ot-map.cc@b8a032363ba2 (annotated)

gfx/harfbuzz/src/hb-ot-map.cc@b8a032363ba2 (annotated)

gfx/harfbuzz/src/hb-ot-map.cc

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
  * Copyright © 2009,2010  Red Hat, Inc.
  * Copyright © 2010,2011,2013  Google, Inc.
  *
  *  This is part of HarfBuzz, a text shaping library.
  *
  * Permission is hereby granted, without written agreement and without
  * license or royalty fees, to use, copy, modify, and distribute this
  * software and its documentation for any purpose, provided that the
  * above copyright notice and the following two paragraphs appear in
  * all copies of this software.
  *
  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  *
  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  *
  * Red Hat Author(s): Behdad Esfahbod
  * Google Author(s): Behdad Esfahbod
  */
 #include "hb-ot-map-private.hh"
 #include "hb-ot-layout-private.hh"
 void
 hb_ot_map_t::add_lookups (hb_face_t    *face,
 			  unsigned int  table_index,
 			  unsigned int  feature_index,
 			  hb_mask_t     mask,
 			  bool          auto_zwj)
 {
   unsigned int lookup_indices[32];
   unsigned int offset, len;
   unsigned int table_lookup_count;
   table_lookup_count = hb_ot_layout_table_get_lookup_count (face, table_tags[table_index]);
   offset = 0;
   do {
     len = ARRAY_LENGTH (lookup_indices);
     hb_ot_layout_feature_get_lookups (face,
 				      table_tags[table_index],
 				      feature_index,
 				      offset, &len,
 				      lookup_indices);
     for (unsigned int i = 0; i < len; i++)
     {
       if (lookup_indices[i] >= table_lookup_count)
 	continue;
       hb_ot_map_t::lookup_map_t *lookup = lookups[table_index].push ();
       if (unlikely (!lookup))
         return;
       lookup->mask = mask;
       lookup->index = lookup_indices[i];
       lookup->auto_zwj = auto_zwj;
     }
     offset += len;
   } while (len == ARRAY_LENGTH (lookup_indices));
 }
 hb_ot_map_builder_t::hb_ot_map_builder_t (hb_face_t *face_,
 					  const hb_segment_properties_t *props_)
 {
   memset (this, 0, sizeof (*this));
   face = face_;
   props = *props_;
   /* Fetch script/language indices for GSUB/GPOS.  We need these later to skip
    * features not available in either table and not waste precious bits for them. */
   hb_tag_t script_tags[3] = {HB_TAG_NONE, HB_TAG_NONE, HB_TAG_NONE};
   hb_tag_t language_tag;
   hb_ot_tags_from_script (props.script, &script_tags[0], &script_tags[1]);
   language_tag = hb_ot_tag_from_language (props.language);
   for (unsigned int table_index = 0; table_index < 2; table_index++) {
     hb_tag_t table_tag = table_tags[table_index];
     found_script[table_index] = hb_ot_layout_table_choose_script (face, table_tag, script_tags, &script_index[table_index], &chosen_script[table_index]);
     hb_ot_layout_script_find_language (face, table_tag, script_index[table_index], language_tag, &language_index[table_index]);
   }
 }
 void hb_ot_map_builder_t::add_feature (hb_tag_t tag, unsigned int value,
 				       hb_ot_map_feature_flags_t flags)
 {
   feature_info_t *info = feature_infos.push();
   if (unlikely (!info)) return;
   info->tag = tag;
   info->seq = feature_infos.len;
   info->max_value = value;
   info->flags = flags;
   info->default_value = (flags & F_GLOBAL) ? value : 0;
   info->stage[0] = current_stage[0];
   info->stage[1] = current_stage[1];
 }
 void hb_ot_map_t::collect_lookups (unsigned int table_index, hb_set_t *lookups_out) const
 {
   for (unsigned int i = 0; i < lookups[table_index].len; i++)
     hb_set_add (lookups_out, lookups[table_index][i].index);
 }
 void hb_ot_map_builder_t::add_pause (unsigned int table_index, hb_ot_map_t::pause_func_t pause_func)
 {
   stage_info_t *s = stages[table_index].push ();
   if (likely (s)) {
     s->index = current_stage[table_index];
     s->pause_func = pause_func;
   }
   current_stage[table_index]++;
 }
 void
 hb_ot_map_builder_t::compile (hb_ot_map_t &m)
 {
   m.global_mask = 1;
   for (unsigned int table_index = 0; table_index < 2; table_index++) {
     m.chosen_script[table_index] = chosen_script[table_index];
     m.found_script[table_index] = found_script[table_index];
   }
   if (!feature_infos.len)
     return;
   /* Sort features and merge duplicates */
   {
     feature_infos.sort ();
     unsigned int j = 0;
     for (unsigned int i = 1; i < feature_infos.len; i++)
       if (feature_infos[i].tag != feature_infos[j].tag)
 	feature_infos[++j] = feature_infos[i];
       else {
 	if (feature_infos[i].flags & F_GLOBAL) {
 	  feature_infos[j].flags |= F_GLOBAL;
 	  feature_infos[j].max_value = feature_infos[i].max_value;
 	  feature_infos[j].default_value = feature_infos[i].default_value;
 	} else {
 	  feature_infos[j].flags &= ~F_GLOBAL;
 	  feature_infos[j].max_value = MAX (feature_infos[j].max_value, feature_infos[i].max_value);
 	  /* Inherit default_value from j */
 	}
 	feature_infos[j].flags |= (feature_infos[i].flags & F_HAS_FALLBACK);
 	feature_infos[j].stage[0] = MIN (feature_infos[j].stage[0], feature_infos[i].stage[0]);
 	feature_infos[j].stage[1] = MIN (feature_infos[j].stage[1], feature_infos[i].stage[1]);
       }
     feature_infos.shrink (j + 1);
   }
   /* Allocate bits now */
   unsigned int next_bit = 1;
   for (unsigned int i = 0; i < feature_infos.len; i++) {
     const feature_info_t *info = &feature_infos[i];
     unsigned int bits_needed;
     if ((info->flags & F_GLOBAL) && info->max_value == 1)
       /* Uses the global bit */
       bits_needed = 0;
     else
       bits_needed = _hb_bit_storage (info->max_value);
     if (!info->max_value || next_bit + bits_needed > 8 * sizeof (hb_mask_t))
       continue; /* Feature disabled, or not enough bits. */
     hb_bool_t found = false;
     unsigned int feature_index[2];
     for (unsigned int table_index = 0; table_index < 2; table_index++)
       found |= hb_ot_layout_language_find_feature (face,
 						   table_tags[table_index],
 						   script_index[table_index],
 						   language_index[table_index],
 						   info->tag,
 						   &feature_index[table_index]);
     if (!found && !(info->flags & F_HAS_FALLBACK))
       continue;
     hb_ot_map_t::feature_map_t *map = m.features.push ();
     if (unlikely (!map))
       break;
     map->tag = info->tag;
     map->index[0] = feature_index[0];
     map->index[1] = feature_index[1];
     map->stage[0] = info->stage[0];
     map->stage[1] = info->stage[1];
     map->auto_zwj = !(info->flags & F_MANUAL_ZWJ);
     if ((info->flags & F_GLOBAL) && info->max_value == 1) {
       /* Uses the global bit */
       map->shift = 0;
       map->mask = 1;
     } else {
       map->shift = next_bit;
       map->mask = (1 << (next_bit + bits_needed)) - (1 << next_bit);
       next_bit += bits_needed;
       m.global_mask |= (info->default_value << map->shift) & map->mask;
     }
     map->_1_mask = (1 << map->shift) & map->mask;
     map->needs_fallback = !found;
   }
   feature_infos.shrink (0); /* Done with these */
   add_gsub_pause (NULL);
   add_gpos_pause (NULL);
   for (unsigned int table_index = 0; table_index < 2; table_index++) {
     hb_tag_t table_tag = table_tags[table_index];
     /* Collect lookup indices for features */
     unsigned int required_feature_index;
     if (hb_ot_layout_language_get_required_feature_index (face,
 							  table_tag,
 							  script_index[table_index],
 							  language_index[table_index],
 							  &required_feature_index))
       m.add_lookups (face, table_index, required_feature_index, 1, true);
     unsigned int stage_index = 0;
     unsigned int last_num_lookups = 0;
     for (unsigned stage = 0; stage < current_stage[table_index]; stage++)
     {
       for (unsigned i = 0; i < m.features.len; i++)
         if (m.features[i].stage[table_index] == stage)
 	  m.add_lookups (face, table_index,
 			 m.features[i].index[table_index],
 			 m.features[i].mask,
 			 m.features[i].auto_zwj);
       /* Sort lookups and merge duplicates */
       if (last_num_lookups < m.lookups[table_index].len)
       {
 	m.lookups[table_index].sort (last_num_lookups, m.lookups[table_index].len);
 	unsigned int j = last_num_lookups;
 	for (unsigned int i = j + 1; i < m.lookups[table_index].len; i++)
 	  if (m.lookups[table_index][i].index != m.lookups[table_index][j].index)
 	    m.lookups[table_index][++j] = m.lookups[table_index][i];
 	  else
 	  {
 	    m.lookups[table_index][j].mask |= m.lookups[table_index][i].mask;
 	    m.lookups[table_index][j].auto_zwj &= m.lookups[table_index][i].auto_zwj;
 	  }
 	m.lookups[table_index].shrink (j + 1);
       }
       last_num_lookups = m.lookups[table_index].len;
       if (stage_index < stages[table_index].len && stages[table_index][stage_index].index == stage) {
 	hb_ot_map_t::stage_map_t *stage_map = m.stages[table_index].push ();
 	if (likely (stage_map)) {
 	  stage_map->last_lookup = last_num_lookups;
 	  stage_map->pause_func = stages[table_index][stage_index].pause_func;
 	}
 	stage_index++;
       }
     }
   }
 }

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gfx/harfbuzz/src/hb-ot-map.cc@b8a032363ba2 (annotated)

gfx/harfbuzz/src/hb-ot-map.cc