1/*
2 * Copyright © 2012,2013  Google, Inc.
3 *
4 *  This is part of HarfBuzz, a text shaping library.
5 *
6 * Permission is hereby granted, without written agreement and without
7 * license or royalty fees, to use, copy, modify, and distribute this
8 * software and its documentation for any purpose, provided that the
9 * above copyright notice and the following two paragraphs appear in
10 * all copies of this software.
11 *
12 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16 * DAMAGE.
17 *
18 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23 *
24 * Google Author(s): Behdad Esfahbod
25 */
26
27#include "hb-buffer-private.hh"
28
29
30static const char *serialize_formats[] = {
31  "text",
32  "json",
33  NULL
34};
35
36/**
37 * hb_buffer_serialize_list_formats:
38 *
39 * Returns a list of supported buffer serialization formats.
40 *
41 * Return value: (transfer none):
42 * A string array of buffer serialization formats. Should not be freed.
43 *
44 * Since: 0.9.7
45 **/
46const char **
47hb_buffer_serialize_list_formats (void)
48{
49  return serialize_formats;
50}
51
52/**
53 * hb_buffer_serialize_format_from_string:
54 * @str: (array length=len) (element-type uint8_t): a string to parse
55 * @len: length of @str, or -1 if string is %NULL terminated
56 *
57 * Parses a string into an #hb_buffer_serialize_format_t. Does not check if
58 * @str is a valid buffer serialization format, use
59 * hb_buffer_serialize_list_formats() to get the list of supported formats.
60 *
61 * Return value:
62 * The parsed #hb_buffer_serialize_format_t.
63 *
64 * Since: 0.9.7
65 **/
66hb_buffer_serialize_format_t
67hb_buffer_serialize_format_from_string (const char *str, int len)
68{
69  /* Upper-case it. */
70  return (hb_buffer_serialize_format_t) (hb_tag_from_string (str, len) & ~0x20202020u);
71}
72
73/**
74 * hb_buffer_serialize_format_to_string:
75 * @format: an #hb_buffer_serialize_format_t to convert.
76 *
77 * Converts @format to the string corresponding it, or %NULL if it is not a valid
78 * #hb_buffer_serialize_format_t.
79 *
80 * Return value: (transfer none):
81 * A %NULL terminated string corresponding to @format. Should not be freed.
82 *
83 * Since: 0.9.7
84 **/
85const char *
86hb_buffer_serialize_format_to_string (hb_buffer_serialize_format_t format)
87{
88  switch (format)
89  {
90    case HB_BUFFER_SERIALIZE_FORMAT_TEXT:	return serialize_formats[0];
91    case HB_BUFFER_SERIALIZE_FORMAT_JSON:	return serialize_formats[1];
92    default:
93    case HB_BUFFER_SERIALIZE_FORMAT_INVALID:	return NULL;
94  }
95}
96
97static unsigned int
98_hb_buffer_serialize_glyphs_json (hb_buffer_t *buffer,
99				  unsigned int start,
100				  unsigned int end,
101				  char *buf,
102				  unsigned int buf_size,
103				  unsigned int *buf_consumed,
104				  hb_font_t *font,
105				  hb_buffer_serialize_flags_t flags)
106{
107  hb_glyph_info_t *info = hb_buffer_get_glyph_infos (buffer, NULL);
108  hb_glyph_position_t *pos = (flags & HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS) ?
109			     NULL : hb_buffer_get_glyph_positions (buffer, NULL);
110
111  *buf_consumed = 0;
112  for (unsigned int i = start; i < end; i++)
113  {
114    char b[1024];
115    char *p = b;
116
117    /* In the following code, we know b is large enough that no overflow can happen. */
118
119#define APPEND(s) HB_STMT_START { strcpy (p, s); p += strlen (s); } HB_STMT_END
120
121    if (i)
122      *p++ = ',';
123
124    *p++ = '{';
125
126    APPEND ("\"g\":");
127    if (!(flags & HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES))
128    {
129      char g[128];
130      hb_font_glyph_to_string (font, info[i].codepoint, g, sizeof (g));
131      *p++ = '"';
132      for (char *q = g; *q; q++) {
133        if (*q == '"')
134	  *p++ = '\\';
135	*p++ = *q;
136      }
137      *p++ = '"';
138    }
139    else
140      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), "%u", info[i].codepoint));
141
142    if (!(flags & HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS)) {
143      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), ",\"cl\":%u", info[i].cluster));
144    }
145
146    if (!(flags & HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS))
147    {
148      p += snprintf (p, ARRAY_LENGTH (b) - (p - b), ",\"dx\":%d,\"dy\":%d",
149		     pos[i].x_offset, pos[i].y_offset);
150      p += snprintf (p, ARRAY_LENGTH (b) - (p - b), ",\"ax\":%d,\"ay\":%d",
151		     pos[i].x_advance, pos[i].y_advance);
152    }
153
154    if (flags & HB_BUFFER_SERIALIZE_FLAG_GLYPH_EXTENTS)
155    {
156      hb_glyph_extents_t extents;
157      hb_font_get_glyph_extents(font, info[i].codepoint, &extents);
158      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), ",\"xb\":%d,\"yb\":%d",
159        extents.x_bearing, extents.y_bearing));
160      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), ",\"w\":%d,\"h\":%d",
161        extents.width, extents.height));
162    }
163
164    *p++ = '}';
165
166    unsigned int l = p - b;
167    if (buf_size > l)
168    {
169      memcpy (buf, b, l);
170      buf += l;
171      buf_size -= l;
172      *buf_consumed += l;
173      *buf = '\0';
174    } else
175      return i - start;
176  }
177
178  return end - start;
179}
180
181static unsigned int
182_hb_buffer_serialize_glyphs_text (hb_buffer_t *buffer,
183				  unsigned int start,
184				  unsigned int end,
185				  char *buf,
186				  unsigned int buf_size,
187				  unsigned int *buf_consumed,
188				  hb_font_t *font,
189				  hb_buffer_serialize_flags_t flags)
190{
191  hb_glyph_info_t *info = hb_buffer_get_glyph_infos (buffer, NULL);
192  hb_glyph_position_t *pos = (flags & HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS) ?
193			     NULL : hb_buffer_get_glyph_positions (buffer, NULL);
194
195  *buf_consumed = 0;
196  for (unsigned int i = start; i < end; i++)
197  {
198    char b[1024];
199    char *p = b;
200
201    /* In the following code, we know b is large enough that no overflow can happen. */
202
203    if (i)
204      *p++ = '|';
205
206    if (!(flags & HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES))
207    {
208      hb_font_glyph_to_string (font, info[i].codepoint, p, 128);
209      p += strlen (p);
210    }
211    else
212      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), "%u", info[i].codepoint));
213
214    if (!(flags & HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS)) {
215      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), "=%u", info[i].cluster));
216    }
217
218    if (!(flags & HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS))
219    {
220      if (pos[i].x_offset || pos[i].y_offset)
221	p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), "@%d,%d", pos[i].x_offset, pos[i].y_offset));
222
223      *p++ = '+';
224      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), "%d", pos[i].x_advance));
225      if (pos[i].y_advance)
226	p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), ",%d", pos[i].y_advance));
227    }
228
229    if (flags & HB_BUFFER_SERIALIZE_FLAG_GLYPH_EXTENTS)
230    {
231      hb_glyph_extents_t extents;
232      hb_font_get_glyph_extents(font, info[i].codepoint, &extents);
233      p += MAX (0, snprintf (p, ARRAY_LENGTH (b) - (p - b), "<%d,%d,%d,%d>", extents.x_bearing, extents.y_bearing, extents.width, extents.height));
234    }
235
236    unsigned int l = p - b;
237    if (buf_size > l)
238    {
239      memcpy (buf, b, l);
240      buf += l;
241      buf_size -= l;
242      *buf_consumed += l;
243      *buf = '\0';
244    } else
245      return i - start;
246  }
247
248  return end - start;
249}
250
251/**
252 * hb_buffer_serialize_glyphs:
253 * @buffer: an #hb_buffer_t buffer.
254 * @start: the first item in @buffer to serialize.
255 * @end: the last item in @buffer to serialize.
256 * @buf: (out) (array length=buf_size) (element-type uint8_t): output string to
257 *       write serialized buffer into.
258 * @buf_size: the size of @buf.
259 * @buf_consumed: (out) (allow-none): if not %NULL, will be set to the number of byes written into @buf.
260 * @font: (allow-none): the #hb_font_t used to shape this buffer, needed to
261 *        read glyph names and extents. If %NULL, and empty font will be used.
262 * @format: the #hb_buffer_serialize_format_t to use for formatting the output.
263 * @flags: the #hb_buffer_serialize_flags_t that control what glyph properties
264 *         to serialize.
265 *
266 * Serializes @buffer into a textual representation of its glyph content,
267 * useful for showing the contents of the buffer, for example during debugging.
268 * There are currently two supported serialization formats:
269 *
270 * ## text
271 * A human-readable, plain text format.
272 * The serialized glyphs will look something like:
273 *
274 * ```
275 * [uni0651=0@518,0+0|uni0628=0+1897]
276 * ```
277 * - The serialized glyphs are delimited with `[` and `]`.
278 * - Glyphs are separated with `|`
279 * - Each glyph starts with glyph name, or glyph index if
280 *   #HB_BUFFER_SERIALIZE_FLAG_NO_GLYPH_NAMES flag is set. Then,
281 *   - If #HB_BUFFER_SERIALIZE_FLAG_NO_CLUSTERS is not set, `=` then #hb_glyph_info_t.cluster.
282 *   - If #HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS is not set, the #hb_glyph_position_t in the format:
283 *     - If both #hb_glyph_position_t.x_offset and #hb_glyph_position_t.y_offset are not 0, `@x_offset,y_offset`. Then,
284 *     - `+x_advance`, then `,y_advance` if #hb_glyph_position_t.y_advance is not 0. Then,
285 *   - If #HB_BUFFER_SERIALIZE_FLAG_GLYPH_EXTENTS is set, the
286 *     #hb_glyph_extents_t in the format
287 *     `&lt;x_bearing,y_bearing,width,height&gt;`
288 *
289 * ## json
290 * TODO.
291 *
292 * Return value:
293 * The number of serialized items.
294 *
295 * Since: 0.9.7
296 **/
297unsigned int
298hb_buffer_serialize_glyphs (hb_buffer_t *buffer,
299			    unsigned int start,
300			    unsigned int end,
301			    char *buf,
302			    unsigned int buf_size,
303			    unsigned int *buf_consumed,
304			    hb_font_t *font,
305			    hb_buffer_serialize_format_t format,
306			    hb_buffer_serialize_flags_t flags)
307{
308  assert (start <= end && end <= buffer->len);
309
310  unsigned int sconsumed;
311  if (!buf_consumed)
312    buf_consumed = &sconsumed;
313  *buf_consumed = 0;
314
315  assert ((!buffer->len && buffer->content_type == HB_BUFFER_CONTENT_TYPE_INVALID) ||
316	  buffer->content_type == HB_BUFFER_CONTENT_TYPE_GLYPHS);
317
318  if (!buffer->have_positions)
319    flags |= HB_BUFFER_SERIALIZE_FLAG_NO_POSITIONS;
320
321  if (unlikely (start == end))
322    return 0;
323
324  if (!font)
325    font = hb_font_get_empty ();
326
327  switch (format)
328  {
329    case HB_BUFFER_SERIALIZE_FORMAT_TEXT:
330      return _hb_buffer_serialize_glyphs_text (buffer, start, end,
331					       buf, buf_size, buf_consumed,
332					       font, flags);
333
334    case HB_BUFFER_SERIALIZE_FORMAT_JSON:
335      return _hb_buffer_serialize_glyphs_json (buffer, start, end,
336					       buf, buf_size, buf_consumed,
337					       font, flags);
338
339    default:
340    case HB_BUFFER_SERIALIZE_FORMAT_INVALID:
341      return 0;
342
343  }
344}
345
346
347static hb_bool_t
348parse_uint (const char *pp, const char *end, uint32_t *pv)
349{
350  char buf[32];
351  unsigned int len = MIN (ARRAY_LENGTH (buf) - 1, (unsigned int) (end - pp));
352  strncpy (buf, pp, len);
353  buf[len] = '\0';
354
355  char *p = buf;
356  char *pend = p;
357  uint32_t v;
358
359  errno = 0;
360  v = strtol (p, &pend, 10);
361  if (errno || p == pend || pend - p != end - pp)
362    return false;
363
364  *pv = v;
365  return true;
366}
367
368static hb_bool_t
369parse_int (const char *pp, const char *end, int32_t *pv)
370{
371  char buf[32];
372  unsigned int len = MIN (ARRAY_LENGTH (buf) - 1, (unsigned int) (end - pp));
373  strncpy (buf, pp, len);
374  buf[len] = '\0';
375
376  char *p = buf;
377  char *pend = p;
378  int32_t v;
379
380  errno = 0;
381  v = strtol (p, &pend, 10);
382  if (errno || p == pend || pend - p != end - pp)
383    return false;
384
385  *pv = v;
386  return true;
387}
388
389#include "hb-buffer-deserialize-json.hh"
390#include "hb-buffer-deserialize-text.hh"
391
392/**
393 * hb_buffer_deserialize_glyphs:
394 * @buffer: an #hb_buffer_t buffer.
395 * @buf: (array length=buf_len):
396 * @buf_len:
397 * @end_ptr: (out):
398 * @font:
399 * @format:
400 *
401 *
402 *
403 * Return value:
404 *
405 * Since: 0.9.7
406 **/
407hb_bool_t
408hb_buffer_deserialize_glyphs (hb_buffer_t *buffer,
409			      const char *buf,
410			      int buf_len, /* -1 means nul-terminated */
411			      const char **end_ptr, /* May be NULL */
412			      hb_font_t *font, /* May be NULL */
413			      hb_buffer_serialize_format_t format)
414{
415  const char *end;
416  if (!end_ptr)
417    end_ptr = &end;
418  *end_ptr = buf;
419
420  assert ((!buffer->len && buffer->content_type == HB_BUFFER_CONTENT_TYPE_INVALID) ||
421	  buffer->content_type == HB_BUFFER_CONTENT_TYPE_GLYPHS);
422
423  if (buf_len == -1)
424    buf_len = strlen (buf);
425
426  if (!buf_len)
427  {
428    *end_ptr = buf;
429    return false;
430  }
431
432  hb_buffer_set_content_type (buffer, HB_BUFFER_CONTENT_TYPE_GLYPHS);
433
434  if (!font)
435    font = hb_font_get_empty ();
436
437  switch (format)
438  {
439    case HB_BUFFER_SERIALIZE_FORMAT_TEXT:
440      return _hb_buffer_deserialize_glyphs_text (buffer,
441						 buf, buf_len, end_ptr,
442						 font);
443
444    case HB_BUFFER_SERIALIZE_FORMAT_JSON:
445      return _hb_buffer_deserialize_glyphs_json (buffer,
446						 buf, buf_len, end_ptr,
447						 font);
448
449    default:
450    case HB_BUFFER_SERIALIZE_FORMAT_INVALID:
451      return false;
452
453  }
454}
455