1
2#line 1 "hb-number-parser.rl"
3/*
4 * Copyright © 2019 Ebrahim Byagowi
5 *
6 * This is part of HarfBuzz, a text shaping library.
7 *
8 * Permission is hereby granted, without written agreement and without
9 * license or royalty fees, to use, copy, modify, and distribute this
10 * software and its documentation for any purpose, provided that the
11 * above copyright notice and the following two paragraphs appear in
12 * all copies of this software.
13 *
14 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
15 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
16 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
17 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
18 * DAMAGE.
19 *
20 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
21 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
22 * FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
23 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
24 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
25 *
26 */
27
28#ifndef HB_NUMBER_PARSER_HH
29#define HB_NUMBER_PARSER_HH
30
31#include "hb.hh"
32
33
34#line 35 "hb-number-parser.hh"
35static const unsigned char _double_parser_trans_keys[] = {
36 0u, 0u, 43u, 57u, 46u, 57u, 48u, 57u, 43u, 57u, 48u, 57u, 48u, 101u, 48u, 57u,
37 46u, 101u, 0
38};
39
40static const char _double_parser_key_spans[] = {
41 0, 15, 12, 10, 15, 10, 54, 10,
42 56
43};
44
45static const unsigned char _double_parser_index_offsets[] = {
46 0, 0, 16, 29, 40, 56, 67, 122,
47 133
48};
49
50static const char _double_parser_indicies[] = {
51 0, 1, 2, 3, 1, 4, 4,
52 4, 4, 4, 4, 4, 4, 4, 4,
53 1, 3, 1, 4, 4, 4, 4, 4,
54 4, 4, 4, 4, 4, 1, 5, 5,
55 5, 5, 5, 5, 5, 5, 5, 5,
56 1, 6, 1, 7, 1, 1, 8, 8,
57 8, 8, 8, 8, 8, 8, 8, 8,
58 1, 8, 8, 8, 8, 8, 8, 8,
59 8, 8, 8, 1, 5, 5, 5, 5,
60 5, 5, 5, 5, 5, 5, 1, 1,
61 1, 1, 1, 1, 1, 1, 1, 1,
62 1, 9, 1, 1, 1, 1, 1, 1,
63 1, 1, 1, 1, 1, 1, 1, 1,
64 1, 1, 1, 1, 1, 1, 1, 1,
65 1, 1, 1, 1, 1, 1, 1, 1,
66 1, 9, 1, 8, 8, 8, 8, 8,
67 8, 8, 8, 8, 8, 1, 3, 1,
68 4, 4, 4, 4, 4, 4, 4, 4,
69 4, 4, 1, 1, 1, 1, 1, 1,
70 1, 1, 1, 1, 1, 9, 1, 1,
71 1, 1, 1, 1, 1, 1, 1, 1,
72 1, 1, 1, 1, 1, 1, 1, 1,
73 1, 1, 1, 1, 1, 1, 1, 1,
74 1, 1, 1, 1, 1, 9, 1, 0
75};
76
77static const char _double_parser_trans_targs[] = {
78 2, 0, 2, 3, 8, 6, 5, 5,
79 7, 4
80};
81
82static const char _double_parser_trans_actions[] = {
83 0, 0, 1, 0, 2, 3, 0, 4,
84 5, 0
85};
86
87static const int double_parser_start = 1;
88static const int double_parser_first_final = 6;
89static const int double_parser_error = 0;
90
91static const int double_parser_en_main = 1;
92
93
94#line 68 "hb-number-parser.rl"
95
96
97/* Works only for n < 512 */
98static inline double
99_pow10 (unsigned exponent)
100{
101 static const double _powers_of_10[] =
102 {
103 1.0e+256,
104 1.0e+128,
105 1.0e+64,
106 1.0e+32,
107 1.0e+16,
108 1.0e+8,
109 10000.,
110 100.,
111 10.
112 };
113 unsigned mask = 1 << (ARRAY_LENGTH (_powers_of_10) - 1);
114 double result = 1;
115 for (const double *power = _powers_of_10; mask; ++power, mask >>= 1)
116 if (exponent & mask) result *= *power;
117 return result;
118}
119
120/* a variant of strtod that also gets end of buffer in its second argument */
121static inline double
122strtod_rl (const char *p, const char **end_ptr /* IN/OUT */)
123{
124 double value = 0;
125 double frac = 0;
126 double frac_count = 0;
127 unsigned exp = 0;
128 bool neg = false, exp_neg = false, exp_overflow = false;
129 const unsigned long long MAX_FRACT = 0xFFFFFFFFFFFFFull; /* 2^52-1 */
130 const unsigned MAX_EXP = 0x7FFu; /* 2^11-1 */
131
132 const char *pe = *end_ptr;
133 while (p < pe && ISSPACE (*p))
134 p++;
135
136 int cs;
137
138#line 139 "hb-number-parser.hh"
139 {
140 cs = double_parser_start;
141 }
142
143#line 144 "hb-number-parser.hh"
144 {
145 int _slen;
146 int _trans;
147 const unsigned char *_keys;
148 const char *_inds;
149 if ( p == pe )
150 goto _test_eof;
151 if ( cs == 0 )
152 goto _out;
153_resume:
154 _keys = _double_parser_trans_keys + (cs<<1);
155 _inds = _double_parser_indicies + _double_parser_index_offsets[cs];
156
157 _slen = _double_parser_key_spans[cs];
158 _trans = _inds[ _slen > 0 && _keys[0] <=(*p) &&
159 (*p) <= _keys[1] ?
160 (*p) - _keys[0] : _slen ];
161
162 cs = _double_parser_trans_targs[_trans];
163
164 if ( _double_parser_trans_actions[_trans] == 0 )
165 goto _again;
166
167 switch ( _double_parser_trans_actions[_trans] ) {
168 case 1:
169#line 37 "hb-number-parser.rl"
170 { neg = true; }
171 break;
172 case 4:
173#line 38 "hb-number-parser.rl"
174 { exp_neg = true; }
175 break;
176 case 2:
177#line 40 "hb-number-parser.rl"
178 {
179 value = value * 10. + ((*p) - '0');
180}
181 break;
182 case 3:
183#line 43 "hb-number-parser.rl"
184 {
185 if (likely (frac <= MAX_FRACT / 10))
186 {
187 frac = frac * 10. + ((*p) - '0');
188 ++frac_count;
189 }
190}
191 break;
192 case 5:
193#line 50 "hb-number-parser.rl"
194 {
195 if (likely (exp * 10 + ((*p) - '0') <= MAX_EXP))
196 exp = exp * 10 + ((*p) - '0');
197 else
198 exp_overflow = true;
199}
200 break;
201#line 202 "hb-number-parser.hh"
202 }
203
204_again:
205 if ( cs == 0 )
206 goto _out;
207 if ( ++p != pe )
208 goto _resume;
209 _test_eof: {}
210 _out: {}
211 }
212
213#line 113 "hb-number-parser.rl"
214
215
216 *end_ptr = p;
217
218 if (frac_count) value += frac / _pow10 (frac_count);
219 if (neg) value *= -1.;
220
221 if (unlikely (exp_overflow))
222 {
223 if (value == 0) return value;
224 if (exp_neg) return neg ? -DBL_MIN : DBL_MIN;
225 else return neg ? -DBL_MAX : DBL_MAX;
226 }
227
228 if (exp)
229 {
230 if (exp_neg) value /= _pow10 (exp);
231 else value *= _pow10 (exp);
232 }
233
234 return value;
235}
236
237#endif /* HB_NUMBER_PARSER_HH */
238