xref: /aosp_15_r20/external/harfbuzz_ng/src/hb-buffer-deserialize-json.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_JSON_HH
28#define HB_BUFFER_DESERIALIZE_JSON_HH
29
30#include "hb.hh"
31
32%%{
33
34machine deserialize_json;
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 ensure_glyphs { if (unlikely (!buffer->ensure_glyphs ())) return false; }
56action ensure_unicode { if (unlikely (!buffer->ensure_unicode ())) return false; }
57
58action parse_glyph_name {
59	/* TODO Unescape \" and \\ if found. */
60	if (!hb_font_glyph_from_string (font,
61					tok+1, p - tok - 2, /* Skip "" */
62					&info.codepoint))
63	  return false;
64}
65
66action parse_codepoint	{ if (!parse_uint (tok, p, &info.codepoint)) return false; }
67action parse_cluster	{ if (!parse_uint (tok, p, &info.cluster )) return false; }
68action parse_x_offset	{ if (!parse_int  (tok, p, &pos.x_offset )) return false; }
69action parse_y_offset	{ if (!parse_int  (tok, p, &pos.y_offset )) return false; }
70action parse_x_advance	{ if (!parse_int  (tok, p, &pos.x_advance)) return false; }
71action parse_y_advance	{ if (!parse_int  (tok, p, &pos.y_advance)) return false; }
72action parse_glyph_flags{ if (!parse_uint (tok, p, &info.mask    )) return false; }
73
74unum	= '0' | [1-9] digit*;
75num	= '-'? unum;
76
77comma = space* ',' space*;
78colon = space* ':' space*;
79
80codepoint = unum;
81glyph_name = '"' ([^\\"] | '\\' [\\"])* '"';
82
83parse_glyph_name   = (glyph_name >tok %parse_glyph_name);
84parse_codepoint = (codepoint >tok %parse_codepoint);
85
86glyph	=  "\"g\""  colon (parse_glyph_name | parse_codepoint);
87unicode	=  "\"u\""  colon parse_codepoint;
88cluster	=  "\"cl\"" colon (unum >tok %parse_cluster);
89xoffset	=  "\"dx\"" colon (num  >tok %parse_x_offset);
90yoffset	=  "\"dy\"" colon (num  >tok %parse_y_offset);
91xadvance=  "\"ax\"" colon (num  >tok %parse_x_advance);
92yadvance=  "\"ay\"" colon (num  >tok %parse_y_advance);
93glyphflags="\"fl\"" colon (unum >tok %parse_glyph_flags);
94
95element = glyph @ensure_glyphs
96	| unicode @ensure_unicode
97	| cluster
98	| xoffset
99	| yoffset
100	| xadvance
101	| yadvance
102	| glyphflags;
103item	=
104	( '{' space* element (comma element)* space* '}')
105	>clear_item
106	@add_item
107	;
108
109main := space* item (comma item)* space* (','|']');
110
111}%%
112
113static hb_bool_t
114_hb_buffer_deserialize_json (hb_buffer_t *buffer,
115				    const char *buf,
116				    unsigned int buf_len,
117				    const char **end_ptr,
118				    hb_font_t *font)
119{
120  const char *p = buf, *pe = buf + buf_len;
121
122  /* Ensure we have positions. */
123  (void) hb_buffer_get_glyph_positions (buffer, nullptr);
124
125  while (p < pe && ISSPACE (*p))
126    p++;
127  if (p < pe && *p == (buffer->len ? ',' : '['))
128    *end_ptr = ++p;
129
130  const char *tok = nullptr;
131  int cs;
132  hb_glyph_info_t info = {0};
133  hb_glyph_position_t pos = {0};
134  %%{
135    write init;
136    write exec;
137  }%%
138
139  *end_ptr = p;
140
141  return p == pe && *(p-1) != ']';
142}
143
144#endif /* HB_BUFFER_DESERIALIZE_JSON_HH */
145