tor-browser

hb-ot-post-table.hh (10247B)

---

/*
* Copyright © 2016  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.
*
* Google Author(s): Behdad Esfahbod
*/

#ifndef HB_OT_POST_TABLE_HH
#define HB_OT_POST_TABLE_HH

#include "hb-open-type.hh"
#include "hb-ot-var-mvar-table.hh"

#define HB_STRING_ARRAY_NAME format1_names
#define HB_STRING_ARRAY_LIST "hb-ot-post-macroman.hh"
#include "hb-string-array.hh"
#undef HB_STRING_ARRAY_LIST
#undef HB_STRING_ARRAY_NAME

/*
* post -- PostScript
* https://docs.microsoft.com/en-us/typography/opentype/spec/post
*/
#define HB_OT_TAG_post HB_TAG('p','o','s','t')


namespace OT {


struct postV2Tail
{
 friend struct post;

 bool sanitize (hb_sanitize_context_t *c) const
 {
   TRACE_SANITIZE (this);
   return_trace (glyphNameIndex.sanitize (c));
 }

 template<typename Iterator>
 bool serialize (hb_serialize_context_t *c,
                 Iterator it,
                 const void* _post) const;

 bool subset (hb_subset_context_t *c) const;

 protected:
 Array16Of<HBUINT16>	glyphNameIndex;	/* This is not an offset, but is the
				 * ordinal number of the glyph in 'post'
				 * string tables. */
/*UnsizedArrayOf<HBUINT8>
		namesX;*/	/* Glyph names with length bytes [variable]
				 * (a Pascal string). */

 public:
 DEFINE_SIZE_ARRAY (2, glyphNameIndex);
};

struct post
{
 static constexpr hb_tag_t tableTag = HB_OT_TAG_post;

 bool serialize (hb_serialize_context_t *c, bool glyph_names) const
 {
   TRACE_SERIALIZE (this);
   post *post_prime = c->allocate_min<post> ();
   if (unlikely (!post_prime))  return_trace (false);

   hb_memcpy (post_prime, this, post::min_size);
   if (!glyph_names)
     return_trace (c->check_assign (post_prime->version.major, 3,
                                    HB_SERIALIZE_ERROR_INT_OVERFLOW)); // Version 3 does not have any glyph names.

   return_trace (true);
 }

 bool subset (hb_subset_context_t *c) const
 {
   TRACE_SUBSET (this);
   auto *post_prime = c->serializer->start_embed<post> ();

   bool glyph_names = c->plan->flags & HB_SUBSET_FLAGS_GLYPH_NAMES;
   if (!serialize (c->serializer, glyph_names))
     return_trace (false);

#ifndef HB_NO_VAR
   if (c->plan->normalized_coords)
   {
     auto &MVAR = *c->plan->source->table.MVAR;
     auto *table = post_prime;

     HB_ADD_MVAR_VAR (HB_OT_METRICS_TAG_UNDERLINE_SIZE,   underlineThickness);
     HB_ADD_MVAR_VAR (HB_OT_METRICS_TAG_UNDERLINE_OFFSET, underlinePosition);
   }
#endif

   Triple *axis_range;
   if (c->plan->user_axes_location.has (HB_TAG ('s','l','n','t'), &axis_range))
   {
     float italic_angle = hb_max (-90.0, hb_min (axis_range->middle, 90.0));
     if (post_prime->italicAngle.to_float () != italic_angle)
       post_prime->italicAngle.set_float (italic_angle);
   }

   if (glyph_names && version.major == 2)
   {
     hb_barrier ();
     return_trace (v2X.subset (c));
   }

   return_trace (true);
 }

 struct accelerator_t
 {
   friend struct postV2Tail;

   accelerator_t (hb_face_t *face)
   {
     table = hb_sanitize_context_t ().reference_table<post> (face);
     unsigned int table_length = table.get_length ();

     version = table->version.to_int ();
     if (version != 0x00020000) return;
     hb_barrier ();

     const postV2Tail &v2 = table->v2X;

     glyphNameIndex = &v2.glyphNameIndex;
     pool = &StructAfter<uint8_t> (v2.glyphNameIndex);

     const uint8_t *end = (const uint8_t *) (const void *) table + table_length;
     index_to_offset.alloc (hb_min (face->get_num_glyphs (), table_length / 8));
     for (const uint8_t *data = pool;
   index_to_offset.length < 65535 && data < end && data + *data < end;
   data += 1 + *data)
index_to_offset.push (data - pool);
   }
   ~accelerator_t ()
   {
     hb_free (gids_sorted_by_name.get_acquire ());
     table.destroy ();
   }

   bool get_glyph_name (hb_codepoint_t glyph,
		 char *buf, unsigned int buf_len) const
   {
     hb_bytes_t s = find_glyph_name (glyph);
     if (!s.length) return false;
     if (!buf_len) return true;
     unsigned int len = hb_min (buf_len - 1, s.length);
     strncpy (buf, s.arrayZ, len);
     buf[len] = '\0';
     return true;
   }

   bool get_glyph_from_name (const char *name, int len,
		      hb_codepoint_t *glyph) const
   {
     unsigned int count = get_glyph_count ();
     if (unlikely (!count)) return false;

     if (len < 0) len = strlen (name);

     if (unlikely (!len)) return false;

   retry:
     uint16_t *gids = gids_sorted_by_name.get_acquire ();

     if (unlikely (!gids))
     {
gids = (uint16_t *) hb_malloc (count * sizeof (gids[0]));
if (unlikely (!gids))
  return false; /* Anything better?! */

for (unsigned int i = 0; i < count; i++)
  gids[i] = i;
hb_qsort (gids, count, sizeof (gids[0]), cmp_gids, (void *) this);

if (unlikely (!gids_sorted_by_name.cmpexch (nullptr, gids)))
{
  hb_free (gids);
  goto retry;
}
     }

     hb_bytes_t st (name, len);
     auto* gid = hb_bsearch (st, gids, count, sizeof (gids[0]), cmp_key, (void *) this);
     if (gid)
     {
*glyph = *gid;
return true;
     }

     return false;
   }

   hb_blob_ptr_t<post> table;

   protected:

   unsigned int get_glyph_count () const
   {
     if (version == 0x00010000)
     {
       hb_barrier ();
return format1_names_length;
     }

     if (version == 0x00020000)
     {
       hb_barrier ();
return glyphNameIndex->len;
     }

     return 0;
   }

   static int cmp_gids (const void *pa, const void *pb, void *arg)
   {
     const accelerator_t *thiz = (const accelerator_t *) arg;
     uint16_t a = * (const uint16_t *) pa;
     uint16_t b = * (const uint16_t *) pb;
     return thiz->find_glyph_name (b).cmp (thiz->find_glyph_name (a));
   }

   static int cmp_key (const void *pk, const void *po, void *arg)
   {
     const accelerator_t *thiz = (const accelerator_t *) arg;
     const hb_bytes_t *key = (const hb_bytes_t *) pk;
     uint16_t o = * (const uint16_t *) po;
     return thiz->find_glyph_name (o).cmp (*key);
   }

   hb_bytes_t find_glyph_name (hb_codepoint_t glyph) const
   {
     if (version == 0x00010000)
     {
       hb_barrier ();
if (glyph >= format1_names_length)
  return hb_bytes_t ();

return format1_names (glyph);
     }

     if (version != 0x00020000)
return hb_bytes_t ();
     hb_barrier ();

     if (glyph >= glyphNameIndex->len)
return hb_bytes_t ();

     unsigned int index = glyphNameIndex->arrayZ[glyph];
     if (index < format1_names_length)
return format1_names (index);
     index -= format1_names_length;

     if (index >= index_to_offset.length)
return hb_bytes_t ();
     unsigned int offset = index_to_offset[index];

     const uint8_t *data = pool + offset;
     unsigned int name_length = *data;
     data++;

     return hb_bytes_t ((const char *) data, name_length);
   }

   private:
   uint32_t version;
   const Array16Of<HBUINT16> *glyphNameIndex = nullptr;
   hb_vector_t<uint32_t> index_to_offset;
   const uint8_t *pool = nullptr;
   mutable hb_atomic_t<uint16_t *> gids_sorted_by_name;
 };

 bool has_data () const { return version.to_int (); }

 bool sanitize (hb_sanitize_context_t *c) const
 {
   TRACE_SANITIZE (this);
   return_trace (c->check_struct (this) &&
	  hb_barrier () &&
	  (version.to_int () == 0x00010000 ||
	   (version.to_int () == 0x00020000 && hb_barrier () && v2X.sanitize (c)) ||
	   version.to_int () == 0x00030000));
 }

 public:
 FixedVersion<>version;		/* 0x00010000 for version 1.0
				 * 0x00020000 for version 2.0
				 * 0x00025000 for version 2.5 (deprecated)
				 * 0x00030000 for version 3.0 */
 F16DOT16	italicAngle;		/* Italic angle in counter-clockwise degrees
				 * from the vertical. Zero for upright text,
				 * negative for text that leans to the right
				 * (forward). */
 FWORD		underlinePosition;	/* This is the suggested distance of the top
				 * of the underline from the baseline
				 * (negative values indicate below baseline).
				 * The PostScript definition of this FontInfo
				 * dictionary key (the y coordinate of the
				 * center of the stroke) is not used for
				 * historical reasons. The value of the
				 * PostScript key may be calculated by
				 * subtracting half the underlineThickness
				 * from the value of this field. */
 FWORD		underlineThickness;	/* Suggested values for the underline
				   thickness. */
 HBUINT32	isFixedPitch;		/* Set to 0 if the font is proportionally
				 * spaced, non-zero if the font is not
				 * proportionally spaced (i.e. monospaced). */
 HBUINT32	minMemType42;		/* Minimum memory usage when an OpenType font
				 * is downloaded. */
 HBUINT32	maxMemType42;		/* Maximum memory usage when an OpenType font
				 * is downloaded. */
 HBUINT32	minMemType1;		/* Minimum memory usage when an OpenType font
				 * is downloaded as a Type 1 font. */
 HBUINT32	maxMemType1;		/* Maximum memory usage when an OpenType font
				 * is downloaded as a Type 1 font. */
 postV2Tail	v2X;
 DEFINE_SIZE_MIN (32);
};

struct post_accelerator_t : post::accelerator_t {
 post_accelerator_t (hb_face_t *face) : post::accelerator_t (face) {}
};


} /* namespace OT */


#endif /* HB_OT_POST_TABLE_HH */