hb-open-file.c

   1 /*
   2 Port from c++ is protected by a GNU Lesser GPLv3
   3 Copyright © 2013 Sylvain BERTRAND <sylvain.bertrand@gmail.com>
   4                                   <sylware@legeek.net>
   5 */
   6 /*XXX:have to go*/
   7 #define _GNU_SOURCE
   8 #include <endian.h>
   9 #include <stdint.h>
  10 #include <stddef.h>
  11
  12 #include "hb.h"
  13 #include "hb-private.h"
  14 #include "hb-open-file-private.h"
  15
  16 static struct ot_fnt_face *ttc_hdr_ver1_get_face(struct ttc_hdr_ver1
  17                                                  *ttc_hdr_ver1, unsigned i)
  18 {
  19         uint32_t of;
  20         uint8_t *base;          /*the beginning of the file */
  21
  22         if (!ttc_hdr_ver1)
  23                 return NULL;
  24
  25         of = be32toh(ttc_hdr_ver1->of_tbls_ofs[i]);
  26         base = (uint8_t *) ttc_hdr_ver1;
  27         return (struct ot_fnt_face *)(base + of);
  28 }
  29
  30 static struct ot_fnt_face *ttc_hdr_get_face(struct ttc_hdr *ttc_hdr, unsigned i)
  31 {
  32         if (!ttc_hdr)
  33                 return NULL;
  34
  35         switch (ttc_hdr->u.hdr.ver.major) {
  36         case 2:         /*version 2 is compatible with version 1 */
  37         case 1:
  38                 return ttc_hdr_ver1_get_face(&ttc_hdr->u.ver1, i);
  39         default:
  40                 return NULL;
  41         }
  42 }
  43
  44 struct ot_fnt_face *ot_fnt_file_get_face(struct ot_fnt_file *ot_fnt_file,
  45                                          unsigned i)
  46 {
  47         uint32_t tag;
  48
  49         if (!ot_fnt_file)
  50                 return NULL;
  51
  52         tag = be32toh(ot_fnt_file->u.tag);
  53
  54         switch (tag) {
  55                 /*Note: for non-collection SFNT data we ignore index.  This is because
  56                    Apple dfont container is a container of SFNT's.  So each SFNT is a
  57                    non-TTC, but the index is more than zero. */
  58         case CFF_TAG:           /*All the non-collection tags */
  59         case TRUE_TAG:
  60         case TYP1_TAG:
  61         case TRUETYPE_TAG:
  62                 return &ot_fnt_file->u.fnt_face;
  63         case TTC_TAG:
  64                 return ttc_hdr_get_face(&ot_fnt_file->u.ttc_hdr, i);
  65         default:
  66                 return NULL;
  67         }
  68 }
  69
  70 static struct tbl_rec *ot_fnt_face_get_tbl(struct ot_fnt_face *ot_fnt_face,
  71                                            unsigned i)
  72 {
  73         /*XXX:check is useless in known code paths */
  74         if (!ot_fnt_face)
  75                 return NULL;
  76
  77         if (i >= ot_fnt_face->tbls_n)
  78                 return NULL;    /*XXX:original code use a "null" object */
  79         return &ot_fnt_face->tbls[i];
  80 }
  81
  82 static hb_bool_t ot_fnt_face_find_tbl_idx(struct ot_fnt_face *ot_fnt_face,
  83                                           hb_tag_t tag, unsigned *tbl_idx)
  84 {
  85         unsigned cnt;
  86         unsigned i;
  87
  88         /*XXX:check is useless in known code paths */
  89         if (!ot_fnt_face)
  90                 return FALSE;
  91
  92         cnt = ot_fnt_face->tbls_n;
  93         for (i = 0; i < cnt; ++i) {
  94                 uint32_t tbl_tag;
  95
  96                 tbl_tag = be32toh(ot_fnt_face->tbls[i].tag);
  97                 if (tag == tbl_tag) {
  98                         if (tbl_idx)
  99                                 *tbl_idx = i;
 100                         return TRUE;
 101                 }
 102         }
 103         if (tbl_idx)
 104                 *tbl_idx = IDX_NOT_FOUND;
 105         return FALSE;
 106 }
 107
 108 struct tbl_rec *ot_fnt_face_get_tbl_by_tag(struct ot_fnt_face *ot_fnt_face,
 109                                            hb_tag_t tag)
 110 {
 111         unsigned tbl_idx;
 112
 113         if (!ot_fnt_face)
 114                 return NULL;
 115
 116         ot_fnt_face_find_tbl_idx(ot_fnt_face, tag, &tbl_idx);
 117         return ot_fnt_face_get_tbl(ot_fnt_face, tbl_idx);
 118 }