xref: /aosp_15_r20/external/harfbuzz_ng/src/hb-buffer-deserialize-text-glyphs.rl (revision 2d1272b857b1f7575e6e246373e1cb218663db8a)
1/*
2 * Copyright © 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#ifndef HB_BUFFER_DESERIALIZE_TEXT_GLYPHS_HH
28#define HB_BUFFER_DESERIALIZE_TEXT_GLYPHS_HH
29
30#include "hb.hh"
31
32%%{
33
34machine deserialize_text_glyphs;
35alphtype unsigned char;
36write data;
37
38action clear_item {
39	hb_memset (&info, 0, sizeof (info));
40	hb_memset (&pos , 0, sizeof (pos ));
41}
42
43action add_item {
44	buffer->add_info (info);
45	if (unlikely (!buffer->successful))
46	  return false;
47	buffer->pos[buffer->len - 1] = pos;
48	*end_ptr = p;
49}
50
51action tok {
52	tok = p;
53}
54
55action parse_glyph {
56	/* TODO Unescape delimiters. */
57	if (!hb_font_glyph_from_string (font,
58					tok, p - tok,
59					&info.codepoint))
60	  return false;
61}
62
63action parse_cluster	{ if (!parse_uint (tok, p, &info.cluster )) return false; }
64action parse_x_offset	{ if (!parse_int  (tok, p, &pos.x_offset )) return false; }
65action parse_y_offset	{ if (!parse_int  (tok, p, &pos.y_offset )) return false; }
66action parse_x_advance	{ if (!parse_int  (tok, p, &pos.x_advance)) return false; }
67action parse_y_advance	{ if (!parse_int  (tok, p, &pos.y_advance)) return false; }
68action parse_glyph_flags{ if (!parse_uint (tok, p, &info.mask    )) return false; }
69
70unum  = '0' | [1-9] digit*;
71num	= '-'? unum;
72
73glyph_id = unum;
74glyph_name = ([^\\\]=@+,#|] | '\\' [\\\]=@+,|]) *;
75
76glyph	= (glyph_id | glyph_name) >tok %parse_glyph;
77cluster	= '=' (unum >tok %parse_cluster);
78offsets	= '@' (num >tok %parse_x_offset)   ',' (num >tok %parse_y_offset );
79advances= '+' (num >tok %parse_x_advance) (',' (num >tok %parse_y_advance))?;
80glyphflags= '#' (unum >tok %parse_glyph_flags);
81
82glyph_item	=
83	(
84		glyph
85		cluster?
86		offsets?
87		advances?
88		glyphflags?
89	)
90	>clear_item
91	%add_item
92	;
93
94glyphs = glyph_item (space* '|' space* glyph_item)* space*;
95
96main := space* glyphs;
97
98}%%
99
100static hb_bool_t
101_hb_buffer_deserialize_text_glyphs (hb_buffer_t *buffer,
102				    const char *buf,
103				    unsigned int buf_len,
104				    const char **end_ptr,
105				    hb_font_t *font)
106{
107  const char *p = buf, *pe = buf + buf_len, *eof = pe, *orig_pe = pe;
108
109  /* Ensure we have positions. */
110  (void) hb_buffer_get_glyph_positions (buffer, nullptr);
111
112  while (p < pe && ISSPACE (*p))
113    p++;
114  if (p < pe && *p == (buffer->len ? '|' : '['))
115    *end_ptr = ++p;
116
117  const char *end = strchr ((char *) p, ']');
118  if (end)
119    pe = eof = end;
120  else
121  {
122    end = strrchr ((char *) p, '|');
123    if (end)
124      pe = eof = end;
125    else
126      pe = eof = p;
127  }
128
129  const char *tok = nullptr;
130  int cs;
131  hb_glyph_info_t info = {0};
132  hb_glyph_position_t pos = {0};
133  %%{
134    write init;
135    write exec;
136  }%%
137
138  if (pe < orig_pe && *pe == ']')
139  {
140    pe++;
141    if (p == pe)
142      p++;
143  }
144
145  *end_ptr = p;
146
147  return p == pe;
148}
149
150#endif /* HB_BUFFER_DESERIALIZE_TEXT_GLYPHS_HH */
151