lib/tapost.c

   1 /* tapost.c */
   2
   3 /*
   4  * Copyright (C) 2011-2014 by Werner Lemberg.
   5  *
   6  * This file is part of the ttfautohint library, and may only be used,
   7  * modified, and distributed under the terms given in `COPYING'.  By
   8  * continuing to use, modify, or distribute this file you indicate that you
   9  * have read `COPYING' and understand and accept it fully.
  10  *
  11  * The file `COPYING' mentioned in the previous paragraph is distributed
  12  * with the ttfautohint library.
  13  */
  14
  15
  16 #include <string.h>
  17
  18 #include "ta.h"
  19
  20
  21 FT_Error
  22 TA_sfnt_update_post_table(SFNT* sfnt,
  23                           FONT* font)
  24 {
  25   SFNT_Table* post_table;
  26   FT_Byte* buf;
  27   FT_ULong buf_len;
  28   FT_Byte* buf_new;
  29   FT_ULong buf_new_len;
  30
  31   FT_ULong version;
  32
  33
  34   if (sfnt->post_idx == MISSING)
  35     return TA_Err_Ok;
  36
  37   post_table = &font->tables[sfnt->post_idx];
  38   buf = post_table->buf;
  39   buf_len = post_table->len;
  40
  41   if (post_table->processed)
  42     return TA_Err_Ok;
  43
  44   version = buf[0] << 24;
  45   version += buf[1] << 16;
  46   version += buf[2] << 8;
  47   version += buf[3];
  48
  49   /* since we have to add a non-standard glyph name, */
  50   /* we must convert `name' tables in formats 1.0 and 2.5 into format 2.0 */
  51
  52   if (version == 0x10000)
  53   {
  54     /* XXX */
  55   }
  56   else if (version == 0x20000)
  57   {
  58     FT_UShort num_glyphs;
  59     FT_UShort max_name_idx;
  60     FT_ULong len;
  61     FT_UShort i;
  62     FT_Byte* p;
  63     FT_Byte* p_new;
  64
  65
  66     num_glyphs = buf[32] << 8;
  67     num_glyphs += buf[33];
  68
  69     p = buf + 34;
  70     max_name_idx = 0;
  71
  72     /* get number of glyph names stored in `names' array */
  73     for (i = 0; i < num_glyphs; i++)
  74     {
  75       FT_UShort idx;
  76
  77
  78       idx = *(p++) << 8;
  79       idx += *(p++);
  80       if (idx >= 258)
  81       {
  82         idx -= 257;
  83         if (idx > max_name_idx)
  84           max_name_idx = idx;
  85       }
  86     }
  87
  88     /* we add one entry to the `glyphNameIndex' array, */
  89     /* and append TTFAUTOHINT_GLYPH_LEN bytes to the `names' array */
  90     buf_new_len = post_table->len + 2 + TTFAUTOHINT_GLYPH_LEN;
  91
  92     /* make the allocated buffer length a multiple of 4 */
  93     len = (buf_new_len + 3) & ~3;
  94     buf_new = (FT_Byte*)malloc(len);
  95     if (!buf_new)
  96       return FT_Err_Out_Of_Memory;
  97
  98     /* pad end of buffer with zeros */
  99     buf_new[len - 1] = 0x00;
 100     buf_new[len - 2] = 0x00;
 101     buf_new[len - 3] = 0x00;
 102
 103     /* copy the table and insert the new data */
 104     p = buf;
 105     p_new = buf_new;
 106
 107     memcpy(p_new, p, 32); /* header */
 108     p += 32;
 109     p_new += 32;
 110
 111     *p_new = HIGH(num_glyphs + 1);
 112     *(p_new + 1) = LOW(num_glyphs + 1);
 113     p += 2;
 114     p_new += 2;
 115
 116     memcpy(p_new, p, num_glyphs * 2); /* glyphNameIndex */
 117     p += num_glyphs * 2;
 118     p_new += num_glyphs * 2;
 119
 120     *p_new = HIGH(max_name_idx + 1 + 257); /* new entry */
 121     *(p_new + 1) = LOW(max_name_idx + 1 + 257);
 122     p_new += 2;
 123
 124     memcpy(p_new, p, buf + buf_len - p); /* names */
 125     p_new += buf + buf_len - p;
 126
 127     strncpy((char*)p_new, TTFAUTOHINT_GLYPH_FIRST_BYTE TTFAUTOHINT_GLYPH,
 128             TTFAUTOHINT_GLYPH_LEN); /* new entry */
 129
 130     free(buf);
 131     post_table->buf = buf_new;
 132     post_table->len = buf_new_len;
 133   }
 134   else if (version == 0x28000)
 135   {
 136     /* XXX */
 137   }
 138   else
 139     goto Done; /* nothing to do for format 3.0 */
 140
 141   post_table->checksum = TA_table_compute_checksum(post_table->buf,
 142                                                    post_table->len);
 143 Done:
 144   post_table->processed = 1;
 145
 146   return TA_Err_Ok;
 147 }
 148
 149 /* end of tapost.c */