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	memset (&info, 0, sizeof (info));
40	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, p - tok,
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; }
72
73unum	= '0' | [1-9] digit*;
74num	= '-'? unum;
75
76comma = space* ',' space*;
77colon = space* ':' space*;
78
79codepoint = unum;
80glyph_name = '"' ([^\\"] | '\\' [\\"])* '"';
81
82parse_glyph_name   = (glyph_name >tok %parse_glyph_name);
83parse_codepoint = (codepoint >tok %parse_codepoint);
84
85glyph	= "\"g\""  colon (parse_glyph_name | parse_codepoint);
86unicode	= "\"u\""  colon parse_codepoint;
87cluster	= "\"cl\"" colon (unum >tok %parse_cluster);
88xoffset	= "\"dx\"" colon (num >tok %parse_x_offset);
89yoffset	= "\"dy\"" colon (num >tok %parse_y_offset);
90xadvance= "\"ax\"" colon (num >tok %parse_x_advance);
91yadvance= "\"ay\"" colon (num >tok %parse_y_advance);
92
93element = glyph @ensure_glyphs
94	| unicode @ensure_unicode
95	| cluster
96	| xoffset
97	| yoffset
98	| xadvance
99	| yadvance;
100item	=
101	( '{' space* element (comma element)* space* '}')
102	>clear_item
103	@add_item
104	;
105
106main := space* item (comma item)* space* (','|']')?;
107
108}%%
109
110static hb_bool_t
111_hb_buffer_deserialize_json (hb_buffer_t *buffer,
112				    const char *buf,
113				    unsigned int buf_len,
114				    const char **end_ptr,
115				    hb_font_t *font)
116{
117  const char *p = buf, *pe = buf + buf_len;
118
119  /* Ensure we have positions. */
120  (void) hb_buffer_get_glyph_positions (buffer, nullptr);
121
122  while (p < pe && ISSPACE (*p))
123    p++;
124  if (p < pe && *p == (buffer->len ? ',' : '['))
125  {
126    *end_ptr = ++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  *end_ptr = p;
139
140  return p == pe && *(p-1) != ']';
141}
142
143#endif /* HB_BUFFER_DESERIALIZE_JSON_HH */
144