1/*
2 * Copyright (c) 2020 - 2023 the ThorVG project. All rights reserved.
3
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10
11 * The above copyright notice and this permission notice shall be included in all
12 * copies or substantial portions of the Software.
13
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20 * SOFTWARE.
21 */
22
23#include <cstring>
24#include <math.h>
25#include <memory.h>
26#include "tvgSvgUtil.h"
27
28/************************************************************************/
29/* Internal Class Implementation */
30/************************************************************************/
31
32static inline bool _floatExact(float a, float b)
33{
34 return memcmp(&a, &b, sizeof(float)) == 0;
35}
36
37static uint8_t _hexCharToDec(const char c)
38{
39 if (c >= 'a') return c - 'a' + 10;
40 else if (c >= 'A') return c - 'A' + 10;
41 else return c - '0';
42}
43
44static uint8_t _base64Value(const char chr)
45{
46 if (chr >= 'A' && chr <= 'Z') return chr - 'A';
47 else if (chr >= 'a' && chr <= 'z') return chr - 'a' + ('Z' - 'A') + 1;
48 else if (chr >= '0' && chr <= '9') return chr - '0' + ('Z' - 'A') + ('z' - 'a') + 2;
49 else if (chr == '+' || chr == '-') return 62;
50 else return 63;
51}
52
53
54/************************************************************************/
55/* External Class Implementation */
56/************************************************************************/
57
58
59/*
60 * https://docs.microsoft.com/en-us/cpp/c-runtime-library/reference/strtof-strtof-l-wcstof-wcstof-l?view=msvc-160
61 *
62 * src should be one of the following form :
63 *
64 * [whitespace] [sign] {digits [radix digits] | radix digits} [{e | E} [sign] digits]
65 * [whitespace] [sign] {INF | INFINITY}
66 * [whitespace] [sign] NAN [sequence]
67 *
68 * No hexadecimal form supported
69 * no sequence supported after NAN
70 */
71float svgUtilStrtof(const char *nPtr, char **endPtr)
72{
73 if (endPtr) *endPtr = (char*)(nPtr);
74 if (!nPtr) return 0.0f;
75
76 auto a = nPtr;
77 auto iter = nPtr;
78 auto val = 0.0f;
79 unsigned long long integerPart = 0;
80 int minus = 1;
81
82 //ignore leading whitespaces
83 while (isspace(*iter)) iter++;
84
85 //signed or not
86 if (*iter == '-') {
87 minus = -1;
88 iter++;
89 } else if (*iter == '+') {
90 iter++;
91 }
92
93 if (tolower(*iter) == 'i') {
94 if ((tolower(*(iter + 1)) == 'n') && (tolower(*(iter + 2)) == 'f')) iter += 3;
95 else goto error;
96
97 if (tolower(*(iter)) == 'i') {
98 if ((tolower(*(iter + 1)) == 'n') && (tolower(*(iter + 2)) == 'i') && (tolower(*(iter + 3)) == 't') && (tolower(*(iter + 4)) == 'y')) iter += 5;
99 else goto error;
100 }
101 if (endPtr) *endPtr = (char *)(iter);
102 return (minus == -1) ? -INFINITY : INFINITY;
103 }
104
105 if (tolower(*iter) == 'n') {
106 if ((tolower(*(iter + 1)) == 'a') && (tolower(*(iter + 2)) == 'n')) iter += 3;
107 else goto error;
108
109 if (endPtr) *endPtr = (char *)(iter);
110 return (minus == -1) ? -NAN : NAN;
111 }
112
113 //Optional: integer part before dot
114 if (isdigit(*iter)) {
115 for (; isdigit(*iter); iter++) {
116 integerPart = integerPart * 10ULL + (unsigned long long)(*iter - '0');
117 }
118 a = iter;
119 } else if (*iter != '.') {
120 goto success;
121 }
122
123 val = static_cast<float>(integerPart);
124
125 //Optional: decimal part after dot
126 if (*iter == '.') {
127 unsigned long long decimalPart = 0;
128 unsigned long long pow10 = 1;
129 int count = 0;
130
131 iter++;
132
133 if (isdigit(*iter)) {
134 for (; isdigit(*iter); iter++, count++) {
135 if (count < 19) {
136 decimalPart = decimalPart * 10ULL + + static_cast<unsigned long long>(*iter - '0');
137 pow10 *= 10ULL;
138 }
139 }
140 } else if (isspace(*iter)) { //skip if there is a space after the dot.
141 a = iter;
142 goto success;
143 }
144
145 val += static_cast<float>(decimalPart) / static_cast<float>(pow10);
146 a = iter;
147 }
148
149 //Optional: exponent
150 if (*iter == 'e' || *iter == 'E') {
151 ++iter;
152
153 //Exception: svg may have 'em' unit for fonts. ex) 5em, 10.5em
154 if ((*iter == 'm') || (*iter == 'M')) {
155 //TODO: We don't support font em unit now, but has to multiply val * font size later...
156 a = iter + 1;
157 goto success;
158 }
159
160 //signed or not
161 int minus_e = 1;
162
163 if (*iter == '-') {
164 minus_e = -1;
165 ++iter;
166 } else if (*iter == '+') {
167 iter++;
168 }
169
170 unsigned int exponentPart = 0;
171
172 if (isdigit(*iter)) {
173 while (*iter == '0') iter++;
174 for (; isdigit(*iter); iter++) {
175 exponentPart = exponentPart * 10U + static_cast<unsigned int>(*iter - '0');
176 }
177 } else if (!isdigit(*(a - 1))) {
178 a = nPtr;
179 goto success;
180 } else if (*iter == 0) {
181 goto success;
182 }
183
184 //if ((_floatExact(val, 2.2250738585072011f)) && ((minus_e * static_cast<int>(exponentPart)) <= -308)) {
185 if ((_floatExact(val, 1.175494351f)) && ((minus_e * static_cast<int>(exponentPart)) <= -38)) {
186 //val *= 1.0e-308f;
187 val *= 1.0e-38f;
188 a = iter;
189 goto success;
190 }
191
192 a = iter;
193 auto scale = 1.0f;
194
195 while (exponentPart >= 8U) {
196 scale *= 1E8;
197 exponentPart -= 8U;
198 }
199 while (exponentPart > 0U) {
200 scale *= 10.0f;
201 exponentPart--;
202 }
203 val = (minus_e == -1) ? (val / scale) : (val * scale);
204 } else if ((iter > nPtr) && !isdigit(*(iter - 1))) {
205 a = nPtr;
206 goto success;
207 }
208
209success:
210 if (endPtr) *endPtr = (char*)(a);
211 return minus * val;
212
213error:
214 if (endPtr) *endPtr = (char*)(nPtr);
215 return 0.0f;
216}
217
218
219string svgUtilURLDecode(const char *src)
220{
221 if (!src) return nullptr;
222
223 auto length = strlen(src);
224 if (length == 0) return nullptr;
225
226 string decoded;
227 decoded.reserve(length);
228
229 char a, b;
230 while (*src) {
231 if (*src == '%' &&
232 ((a = src[1]) && (b = src[2])) &&
233 (isxdigit(a) && isxdigit(b))) {
234 decoded += (_hexCharToDec(a) << 4) + _hexCharToDec(b);
235 src+=3;
236 } else if (*src == '+') {
237 decoded += ' ';
238 src++;
239 } else {
240 decoded += *src++;
241 }
242 }
243 return decoded;
244}
245
246
247string svgUtilBase64Decode(const char *src)
248{
249 if (!src) return nullptr;
250
251 auto length = strlen(src);
252 if (length == 0) return nullptr;
253
254 string decoded;
255 decoded.reserve(3*(1+(length >> 2)));
256
257 while (*src && *(src+1)) {
258 if (*src <= 0x20) {
259 ++src;
260 continue;
261 }
262
263 auto value1 = _base64Value(src[0]);
264 auto value2 = _base64Value(src[1]);
265 decoded += (value1 << 2) + ((value2 & 0x30) >> 4);
266
267 if (!src[2] || src[2] == '=' || src[2] == '.') break;
268 auto value3 = _base64Value(src[2]);
269 decoded += ((value2 & 0x0f) << 4) + ((value3 & 0x3c) >> 2);
270
271 if (!src[3] || src[3] == '=' || src[3] == '.') break;
272 auto value4 = _base64Value(src[3]);
273 decoded += ((value3 & 0x03) << 6) + value4;
274 src += 4;
275 }
276 return decoded;
277}
278
279
280char* svgUtilStrndup(const char* str, size_t n)
281{
282 auto len = strlen(str);
283 if (len < n) n = len;
284
285 auto ret = (char*)malloc(n + 1);
286 if (!ret) return nullptr;
287 ret[n] = '\0';
288
289 return (char*)memcpy(ret, str, n);
290}
291