summaryrefslogtreecommitdiff
path: root/Build/source/texk/web2c/luatexdir/font/sfnt.w
blob: ace1b82233dc1668363126f49a8568440af63ca5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
% sfnt.w
%
% Copyright 2002 by Jin-Hwan Cho and Shunsaku Hirata,
% the dvipdfmx project team <dvipdfmx@@project.ktug.or.kr>
% Copyright 2006-2008 Taco Hoekwater <taco@@luatex.org>
%
% This file is part of LuaTeX.
%
% LuaTeX is free software; you can redistribute it and/or modify it under
% the terms of the GNU General Public License as published by the Free
% Software Foundation; either version 2 of the License, or (at your
% option) any later version.
%
% LuaTeX is distributed in the hope that it will be useful, but WITHOUT
% ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
% FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
% License for more details.
%
% You should have received a copy of the GNU General Public License along
% with LuaTeX; if not, see <http://www.gnu.org/licenses/>.

@ Based on dvipdfmx-0.13.2c
@c
static const char _svn_version[] =
    "$Id: sfnt.w 4457 2012-07-13 13:16:19Z taco $"
    "$URL: http://foundry.supelec.fr/svn/luatex/trunk/source/texk/web2c/luatexdir/font/sfnt.w $";

#if  HAVE_CONFIG_H
#  include <w2c/config.h>
#endif                          /* |HAVE_CONFIG_H_| */

#include <string.h>

#  include "ptexlib.h"
#include "font/sfnt.h"

@ type:

 `true' (0x74727565): TrueType (Mac)

 `typ1' (0x74797031) (Mac): PostScript font housed in a sfnt wrapper

 0x00010000: TrueType (Win)/OpenType

 `OTTO': PostScript CFF font with OpenType wrapper

 `ttcf': TrueType Collection

@c
#define SFNT_TRUETYPE   0x00010000UL
#define SFNT_MAC_TRUE 0x74727565UL
#define SFNT_OPENTYPE   0x00010000UL
#define SFNT_POSTSCRIPT 0x4f54544fUL
#define SFNT_TTC        0x74746366UL

sfnt *sfnt_open(unsigned char *buff, int buflen)
{
    sfnt *sfont;
    ULONG type;

    sfont = xmalloc(sizeof(sfnt));
    sfont->loc = 0;
    sfont->buffer = buff;
    sfont->buflen = buflen;

    type = sfnt_get_ulong(sfont);

    if (type == SFNT_TRUETYPE || type == SFNT_MAC_TRUE) {
        sfont->type = SFNT_TYPE_TRUETYPE;
    } else if (type == SFNT_OPENTYPE) {
        sfont->type = SFNT_TYPE_OPENTYPE;
    } else if (type == SFNT_POSTSCRIPT) {
        sfont->type = SFNT_TYPE_POSTSCRIPT;
    } else if (type == SFNT_TTC) {
        sfont->type = SFNT_TYPE_TTC;
    }

    sfont->loc = 0;
    sfont->directory = NULL;
    return sfont;
}

static void release_directory(struct sfnt_table_directory *td)
{
    long i;

    if (td) {
        if (td->tables) {
            for (i = 0; i < td->num_tables; i++) {
                if (td->tables[i].data)
                    RELEASE(td->tables[i].data);
            }
            RELEASE(td->tables);
        }
        if (td->flags)
            RELEASE(td->flags);
        RELEASE(td);
    }

    return;
}

void sfnt_close(sfnt * sfont)
{

    if (sfont) {
        if (sfont->directory)
            release_directory(sfont->directory);
        RELEASE(sfont);
    }

    return;
}

int put_big_endian(void *s, LONG q, int n)
{
    int i;
    char *p;

    p = (char *) s;
    for (i = n - 1; i >= 0; i--) {
        p[i] = (char) (q & 0xff);
        q >>= 8;
    }

    return n;
}

@ Convert four-byte number to big endianess in a machine independent way.

@c
static void convert_tag(char *tag, unsigned long u_tag)
{
    int i;

    for (i = 3; i >= 0; i--) {
        tag[i] = (char) (u_tag % 256);
        u_tag /= 256;
    }

    return;
}


@ Computes the max power of 2 <= n
 
@c
static unsigned max2floor(unsigned n)
{
    int val = 1;

    while (n > 1) {
        n /= 2;
        val *= 2;
    }

    return (unsigned) val;
}


@ Computes the log2 of the max power of 2 <= n

@c
static unsigned log2floor(unsigned n)
{
    unsigned val = 0;

    while (n > 1) {
        n /= 2;
        val++;
    }

    return val;
}

@ @c
static ULONG sfnt_calc_checksum(void *data, ULONG length)
{
    ULONG chksum = 0;
    BYTE *p, *endptr;
    ULONG count = 0;

    p = (BYTE *) data;
    endptr = p + length;
    while (p < endptr) {
        chksum = chksum + (ULONG) (p[0] << (8 * (3 - count)));
        count = ((count + 1) & 3);
        p++;
    }

    return chksum;
}

@ @c
static int find_table_index(struct sfnt_table_directory *td, const char *tag)
{
    int idx;

    if (!td)
        return -1;

    for (idx = 0; idx < td->num_tables; idx++) {
        if (!memcmp(td->tables[idx].tag, tag, 4))
            return idx;
    }

    return -1;
}

@ @c
void sfnt_set_table(sfnt * sfont, const char *tag, void *data, ULONG length)
{
    struct sfnt_table_directory *td;
    int idx;

    ASSERT(sfont);

    td = sfont->directory;
    idx = find_table_index(td, tag);

    if (idx < 0) {
        idx = td->num_tables;
        td->num_tables++;
        td->tables = RENEW(td->tables, td->num_tables, struct sfnt_table);
        memcpy(td->tables[idx].tag, tag, 4);
    }

    td->tables[idx].check_sum = sfnt_calc_checksum(data, length);
    td->tables[idx].offset = 0L;
    td->tables[idx].length = length;
    td->tables[idx].data = data;

    return;
}

@ @c
ULONG sfnt_find_table_len(sfnt * sfont, const char *tag)
{
    ULONG length;
    struct sfnt_table_directory *td;
    int idx;

    ASSERT(sfont && tag);

    td = sfont->directory;
    idx = find_table_index(td, tag);
    if (idx < 0)
        length = 0;
    else {
        length = td->tables[idx].length;
    }

    return length;
}

@ @c
ULONG sfnt_find_table_pos(sfnt * sfont, const char *tag)
{
    ULONG offset;
    struct sfnt_table_directory *td;
    int idx;

    ASSERT(sfont && tag);

    td = sfont->directory;
    idx = find_table_index(td, tag);
    if (idx < 0)
        offset = 0;
    else {
        offset = td->tables[idx].offset;
    }

    return offset;
}

@ @c
ULONG sfnt_locate_table(sfnt * sfont, const char *tag)
{
    ULONG offset;

    ASSERT(sfont && tag);

    offset = sfnt_find_table_pos(sfont, tag);
    if (offset == 0)
        TT_ERROR("sfnt: table not found...");

    sfnt_seek_set(sfont, (long) offset);

    return offset;
}

@ @c
int sfnt_read_table_directory(sfnt * sfont, ULONG offset)
{
    struct sfnt_table_directory *td;
    unsigned long i, u_tag;

    ASSERT(sfont);

    if (sfont->directory)
        release_directory(sfont->directory);
    sfont->directory = td = NEW(1, struct sfnt_table_directory);

    ASSERT(sfont->buffer);
    sfnt_seek_set(sfont, (long) offset);

    td->version = sfnt_get_ulong(sfont);
    td->num_tables = sfnt_get_ushort(sfont);
    td->search_range = sfnt_get_ushort(sfont);
    td->entry_selector = sfnt_get_ushort(sfont);
    td->range_shift = sfnt_get_ushort(sfont);

    td->flags = NEW(td->num_tables, char);
    td->tables = NEW(td->num_tables, struct sfnt_table);

    for (i = 0; i < td->num_tables; i++) {
        u_tag = sfnt_get_ulong(sfont);

        convert_tag(td->tables[i].tag, u_tag);
        td->tables[i].check_sum = sfnt_get_ulong(sfont);
        td->tables[i].offset = sfnt_get_ulong(sfont);
        td->tables[i].length = sfnt_get_ulong(sfont);
        td->tables[i].data = NULL;

        td->flags[i] = 0;
    }

    td->num_kept_tables = 0;

    return 0;
}

@ @c
int sfnt_require_table(sfnt * sfont, const char *tag, int must_exist)
{
    struct sfnt_table_directory *td;
    int idx;

    ASSERT(sfont && sfont->directory);

    td = sfont->directory;
    idx = find_table_index(td, tag);
    if (idx < 0) {
        if (must_exist)
            return -1;
    } else {
        td->flags[idx] |= SFNT_TABLE_REQUIRED;
        td->num_kept_tables++;
    }

    return 0;
}



@ All tables begin on four byte boundries, and pad any remaining space
  between tables with zeros

  Entries in the Table Directory must be sorted in ascending order by tag

  The head table contains checksum of the whole font file.
  To compute:  first set it to 0, sum the entire font as ULONG,
  then store 0xB1B0AFBA - sum.

@c
#  include "font/luatexfont.h"
#  undef MIN
#  define MIN(a, b) (((a) < (b)) ? (a) : (b))
#  define STREAM_COMPRESS

static unsigned char wbuf[1024], padbytes[4] = { 0, 0, 0, 0 };

pdf_obj *sfnt_create_FontFile_stream(sfnt * sfont)
{
    pdf_obj *stream;
    struct sfnt_table_directory *td;
    long offset, nb_read, length;
    int i, sr;
    char *p;

    ASSERT(sfont && sfont->directory);

    stream = pdf_new_stream(STREAM_COMPRESS);

    td = sfont->directory;

    /* Header */
    p = (char *) wbuf;
    p += sfnt_put_ulong(p, (LONG) td->version);
    p += sfnt_put_ushort(p, td->num_kept_tables);
    sr = (int) (max2floor(td->num_kept_tables) * 16);
    p += sfnt_put_ushort(p, sr);
    p += sfnt_put_ushort(p, log2floor(td->num_kept_tables));
    p += sfnt_put_ushort(p, td->num_kept_tables * 16 - sr);

    pdf_add_stream(stream, wbuf, 12);

    /*
     Compute start of actual tables (after headers).
     */
    offset = 12 + 16 * td->num_kept_tables;
    for (i = 0; i < td->num_tables; i++) {
        /* This table must exist in FontFile */
        if (td->flags[i] & SFNT_TABLE_REQUIRED) {
            if ((offset % 4) != 0) {
                offset += 4 - (offset % 4);
            }

            p = (char *) wbuf;
            memcpy(p, td->tables[i].tag, 4);
            p += 4;
            p += sfnt_put_ulong(p, (LONG) td->tables[i].check_sum);
            p += sfnt_put_ulong(p, offset);
            p += sfnt_put_ulong(p, (LONG) td->tables[i].length);
            pdf_add_stream(stream, wbuf, 16);

            offset = (long) (offset + (long) td->tables[i].length);
        }
    }

    offset = 12 + 16 * td->num_kept_tables;
    for (i = 0; i < td->num_tables; i++) {
        if (td->flags[i] & SFNT_TABLE_REQUIRED) {
            if ((offset % 4) != 0) {
                length = 4 - (offset % 4);
                pdf_add_stream(stream, padbytes, length);
                offset += length;
            }
            if (!td->tables[i].data) {
                if (!sfont->buffer)
                {
                    pdf_release_obj(stream);
                    TT_ERROR("Font file not opened or already closed...");
                    return NULL;
                }

                length = (long) td->tables[i].length;
                sfnt_seek_set(sfont, (long) td->tables[i].offset);
                while (length > 0) {
                    nb_read = sfnt_read(wbuf, (int) MIN(length, 1024), sfont);
                    if (nb_read < 0) {
                        pdf_release_obj(stream);
                        TT_ERROR("Reading file failed...");
                        return NULL;
                    } else if (nb_read > 0) {
                        pdf_add_stream(stream, wbuf, nb_read);
                    }
                    length -= nb_read;
                }
            } else {
                pdf_add_stream(stream,
                               (unsigned char *) td->tables[i].data,
                               (long) td->tables[i].length);
                RELEASE(td->tables[i].data);
                td->tables[i].data = NULL;
            }
            /* Set offset for next table */
            offset = (long) (offset + (long) td->tables[i].length);
        }
    }

    return stream;
}