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Rev | Author | Line No. | Line |
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4349 | Serge | 1 | |
2 | * |
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3 | * Last changed in libpng 1.6.4 [September 14, 2013] |
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4 | * Copyright (c) 1998-2013 Glenn Randers-Pehrson |
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5 | * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
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6 | * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
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7 | * |
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8 | * This code is released under the libpng license. |
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9 | * For conditions of distribution and use, see the disclaimer |
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10 | * and license in png.h |
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11 | * |
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12 | * This file contains routines that are only called from within |
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13 | * libpng itself during the course of reading an image. |
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14 | */ |
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15 | |||
16 | |||
17 | |||
18 | |||
19 | |||
20 | |||
21 | png_get_uint_31(png_const_structrp png_ptr, png_const_bytep buf) |
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22 | { |
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23 | png_uint_32 uval = png_get_uint_32(buf); |
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24 | |||
25 | |||
26 | png_error(png_ptr, "PNG unsigned integer out of range"); |
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27 | |||
28 | |||
29 | } |
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30 | |||
31 | |||
32 | /* The following is a variation on the above for use with the fixed |
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33 | * point values used for gAMA and cHRM. Instead of png_error it |
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34 | * issues a warning and returns (-1) - an invalid value because both |
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35 | * gAMA and cHRM use *unsigned* integers for fixed point values. |
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36 | */ |
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37 | #define PNG_FIXED_ERROR (-1) |
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38 | |||
39 | |||
40 | png_get_fixed_point(png_structrp png_ptr, png_const_bytep buf) |
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41 | { |
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42 | png_uint_32 uval = png_get_uint_32(buf); |
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43 | |||
44 | |||
45 | return (png_fixed_point)uval; /* known to be in range */ |
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46 | |||
47 | |||
48 | if (png_ptr != NULL) |
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49 | png_warning(png_ptr, "PNG fixed point integer out of range"); |
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50 | |||
51 | |||
52 | } |
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53 | #endif |
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54 | |||
55 | |||
56 | /* NOTE: the read macros will obscure these definitions, so that if |
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57 | * PNG_USE_READ_MACROS is set the library will not use them internally, |
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58 | * but the APIs will still be available externally. |
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59 | * |
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60 | * The parentheses around "PNGAPI function_name" in the following three |
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61 | * functions are necessary because they allow the macros to co-exist with |
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62 | * these (unused but exported) functions. |
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63 | */ |
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64 | |||
65 | |||
66 | png_uint_32 (PNGAPI |
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67 | png_get_uint_32)(png_const_bytep buf) |
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68 | { |
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69 | png_uint_32 uval = |
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70 | ((png_uint_32)(*(buf )) << 24) + |
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71 | ((png_uint_32)(*(buf + 1)) << 16) + |
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72 | ((png_uint_32)(*(buf + 2)) << 8) + |
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73 | ((png_uint_32)(*(buf + 3)) ) ; |
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74 | |||
75 | |||
76 | } |
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77 | |||
78 | |||
79 | * data is stored in the PNG file in two's complement format and there |
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80 | * is no guarantee that a 'png_int_32' is exactly 32 bits, therefore |
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81 | * the following code does a two's complement to native conversion. |
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82 | */ |
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83 | png_int_32 (PNGAPI |
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84 | png_get_int_32)(png_const_bytep buf) |
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85 | { |
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86 | png_uint_32 uval = png_get_uint_32(buf); |
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87 | if ((uval & 0x80000000) == 0) /* non-negative */ |
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88 | return uval; |
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89 | |||
90 | |||
91 | return -(png_int_32)uval; |
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92 | } |
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93 | |||
94 | |||
95 | png_uint_16 (PNGAPI |
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96 | png_get_uint_16)(png_const_bytep buf) |
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97 | { |
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98 | /* ANSI-C requires an int value to accomodate at least 16 bits so this |
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99 | * works and allows the compiler not to worry about possible narrowing |
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100 | * on 32 bit systems. (Pre-ANSI systems did not make integers smaller |
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101 | * than 16 bits either.) |
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102 | */ |
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103 | unsigned int val = |
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104 | ((unsigned int)(*buf) << 8) + |
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105 | ((unsigned int)(*(buf + 1))); |
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106 | |||
107 | |||
108 | } |
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109 | |||
110 | |||
111 | |||
112 | |||
113 | void /* PRIVATE */ |
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114 | png_read_sig(png_structrp png_ptr, png_inforp info_ptr) |
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115 | { |
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116 | png_size_t num_checked, num_to_check; |
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117 | |||
118 | |||
119 | if (png_ptr->sig_bytes >= 8) |
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120 | return; |
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121 | |||
122 | |||
123 | num_to_check = 8 - num_checked; |
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124 | |||
125 | |||
126 | png_ptr->io_state = PNG_IO_READING | PNG_IO_SIGNATURE; |
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127 | #endif |
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128 | |||
129 | |||
130 | png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); |
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131 | png_ptr->sig_bytes = 8; |
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132 | |||
133 | |||
134 | { |
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135 | if (num_checked < 4 && |
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136 | png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) |
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137 | png_error(png_ptr, "Not a PNG file"); |
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138 | else |
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139 | png_error(png_ptr, "PNG file corrupted by ASCII conversion"); |
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140 | } |
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141 | if (num_checked < 3) |
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142 | png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; |
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143 | } |
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144 | |||
145 | |||
146 | * Put the type name into png_ptr->chunk_name, and return the length. |
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147 | */ |
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148 | png_uint_32 /* PRIVATE */ |
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149 | png_read_chunk_header(png_structrp png_ptr) |
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150 | { |
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151 | png_byte buf[8]; |
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152 | png_uint_32 length; |
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153 | |||
154 | |||
155 | png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_HDR; |
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156 | #endif |
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157 | |||
158 | |||
159 | * This must be performed in a single I/O call. |
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160 | */ |
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161 | png_read_data(png_ptr, buf, 8); |
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162 | length = png_get_uint_31(png_ptr, buf); |
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163 | |||
164 | |||
165 | png_ptr->chunk_name = PNG_CHUNK_FROM_STRING(buf+4); |
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166 | |||
167 | |||
168 | (unsigned long)png_ptr->chunk_name, (unsigned long)length); |
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169 | |||
170 | |||
171 | png_reset_crc(png_ptr); |
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172 | png_calculate_crc(png_ptr, buf + 4, 4); |
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173 | |||
174 | |||
175 | png_check_chunk_name(png_ptr, png_ptr->chunk_name); |
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176 | |||
177 | |||
178 | png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_DATA; |
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179 | #endif |
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180 | |||
181 | |||
182 | } |
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183 | |||
184 | |||
185 | void /* PRIVATE */ |
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186 | png_crc_read(png_structrp png_ptr, png_bytep buf, png_uint_32 length) |
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187 | { |
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188 | if (png_ptr == NULL) |
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189 | return; |
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190 | |||
191 | |||
192 | png_calculate_crc(png_ptr, buf, length); |
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193 | } |
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194 | |||
195 | |||
196 | * are reading an ancillary or critical chunk, and how the program has set |
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197 | * things up, we may calculate the CRC on the data and print a message. |
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198 | * Returns '1' if there was a CRC error, '0' otherwise. |
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199 | */ |
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200 | int /* PRIVATE */ |
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201 | png_crc_finish(png_structrp png_ptr, png_uint_32 skip) |
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202 | { |
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203 | /* The size of the local buffer for inflate is a good guess as to a |
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204 | * reasonable size to use for buffering reads from the application. |
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205 | */ |
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206 | while (skip > 0) |
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207 | { |
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208 | png_uint_32 len; |
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209 | png_byte tmpbuf[PNG_INFLATE_BUF_SIZE]; |
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210 | |||
211 | |||
212 | if (len > skip) |
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213 | len = skip; |
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214 | skip -= len; |
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215 | |||
216 | |||
217 | } |
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218 | |||
219 | |||
220 | { |
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221 | if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name) ? |
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222 | !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) : |
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223 | (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE)) |
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224 | { |
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225 | png_chunk_warning(png_ptr, "CRC error"); |
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226 | } |
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227 | |||
228 | |||
229 | { |
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230 | png_chunk_benign_error(png_ptr, "CRC error"); |
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231 | return (0); |
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232 | } |
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233 | |||
234 | |||
235 | } |
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236 | |||
237 | |||
238 | } |
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239 | |||
240 | |||
241 | * the data it has read thus far. |
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242 | */ |
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243 | int /* PRIVATE */ |
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244 | png_crc_error(png_structrp png_ptr) |
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245 | { |
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246 | png_byte crc_bytes[4]; |
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247 | png_uint_32 crc; |
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248 | int need_crc = 1; |
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249 | |||
250 | |||
251 | { |
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252 | if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) == |
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253 | (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN)) |
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254 | need_crc = 0; |
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255 | } |
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256 | |||
257 | |||
258 | { |
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259 | if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE) |
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260 | need_crc = 0; |
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261 | } |
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262 | |||
263 | |||
264 | png_ptr->io_state = PNG_IO_READING | PNG_IO_CHUNK_CRC; |
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265 | #endif |
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266 | |||
267 | |||
268 | png_read_data(png_ptr, crc_bytes, 4); |
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269 | |||
270 | |||
271 | { |
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272 | crc = png_get_uint_32(crc_bytes); |
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273 | return ((int)(crc != png_ptr->crc)); |
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274 | } |
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275 | |||
276 | |||
277 | return (0); |
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278 | } |
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279 | |||
280 | |||
281 | * enough (or if it is not allocated). The routine returns a pointer to the |
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282 | * buffer; if an error occurs and 'warn' is set the routine returns NULL, else |
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283 | * it will call png_error (via png_malloc) on failure. (warn == 2 means |
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284 | * 'silent'). |
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285 | */ |
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286 | static png_bytep |
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287 | png_read_buffer(png_structrp png_ptr, png_alloc_size_t new_size, int warn) |
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288 | { |
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289 | png_bytep buffer = png_ptr->read_buffer; |
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290 | |||
291 | |||
292 | { |
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293 | png_ptr->read_buffer = NULL; |
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294 | png_ptr->read_buffer = NULL; |
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295 | png_ptr->read_buffer_size = 0; |
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296 | png_free(png_ptr, buffer); |
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297 | buffer = NULL; |
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298 | } |
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299 | |||
300 | |||
301 | { |
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302 | buffer = png_voidcast(png_bytep, png_malloc_base(png_ptr, new_size)); |
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303 | |||
304 | |||
305 | { |
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306 | png_ptr->read_buffer = buffer; |
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307 | png_ptr->read_buffer_size = new_size; |
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308 | } |
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309 | |||
310 | |||
311 | { |
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312 | #ifdef PNG_WARNINGS_SUPPORTED |
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313 | if (warn) |
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314 | png_chunk_warning(png_ptr, "insufficient memory to read chunk"); |
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315 | else |
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316 | #endif |
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317 | { |
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318 | #ifdef PNG_ERROR_TEXT_SUPPORTED |
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319 | png_chunk_error(png_ptr, "insufficient memory to read chunk"); |
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320 | #endif |
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321 | } |
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322 | } |
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323 | } |
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324 | |||
325 | |||
326 | } |
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327 | |||
328 | |||
329 | * decompression. Returns Z_OK on success, else a zlib error code. It checks |
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330 | * the owner but, in final release builds, just issues a warning if some other |
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331 | * chunk apparently owns the stream. Prior to release it does a png_error. |
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332 | */ |
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333 | static int |
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334 | png_inflate_claim(png_structrp png_ptr, png_uint_32 owner) |
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335 | { |
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336 | if (png_ptr->zowner != 0) |
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337 | { |
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338 | char msg[64]; |
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339 | |||
340 | |||
341 | /* So the message that results is " |
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342 | * internal error, but is very useful for debugging. i18n requirements |
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343 | * are minimal. |
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344 | */ |
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345 | (void)png_safecat(msg, (sizeof msg), 4, " using zstream"); |
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346 | # if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC |
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347 | png_chunk_warning(png_ptr, msg); |
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348 | png_ptr->zowner = 0; |
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349 | # else |
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350 | png_chunk_error(png_ptr, msg); |
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351 | # endif |
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352 | } |
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353 | |||
354 | |||
355 | * does not take the size of the data as an argument. Some efficiency could |
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356 | * be gained by using this when it is known *if* the zlib stream itself does |
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357 | * not record the number; however, this is an illusion: the original writer |
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358 | * of the PNG may have selected a lower window size, and we really must |
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359 | * follow that because, for systems with with limited capabilities, we |
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360 | * would otherwise reject the application's attempts to use a smaller window |
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361 | * size (zlib doesn't have an interface to say "this or lower"!). |
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362 | * |
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363 | * inflateReset2 was added to zlib 1.2.4; before this the window could not be |
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364 | * reset, therefore it is necessary to always allocate the maximum window |
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365 | * size with earlier zlibs just in case later compressed chunks need it. |
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366 | */ |
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367 | { |
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368 | int ret; /* zlib return code */ |
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369 | # if PNG_ZLIB_VERNUM >= 0x1240 |
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370 | |||
371 | |||
372 | defined(PNG_MAXIMUM_INFLATE_WINDOW) |
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373 | int window_bits; |
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374 | |||
375 | |||
376 | PNG_OPTION_ON) |
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377 | window_bits = 15; |
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378 | |||
379 | |||
380 | window_bits = 0; |
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381 | # else |
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382 | # define window_bits 0 |
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383 | # endif |
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384 | # endif |
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385 | |||
386 | |||
387 | * memory allocations. |
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388 | */ |
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389 | png_ptr->zstream.next_in = NULL; |
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390 | png_ptr->zstream.avail_in = 0; |
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391 | png_ptr->zstream.next_out = NULL; |
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392 | png_ptr->zstream.avail_out = 0; |
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393 | |||
394 | |||
395 | { |
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396 | # if PNG_ZLIB_VERNUM < 0x1240 |
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397 | ret = inflateReset(&png_ptr->zstream); |
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398 | # else |
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399 | ret = inflateReset2(&png_ptr->zstream, window_bits); |
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400 | # endif |
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401 | } |
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402 | |||
403 | |||
404 | { |
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405 | # if PNG_ZLIB_VERNUM < 0x1240 |
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406 | ret = inflateInit(&png_ptr->zstream); |
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407 | # else |
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408 | ret = inflateInit2(&png_ptr->zstream, window_bits); |
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409 | # endif |
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410 | |||
411 | |||
412 | png_ptr->flags |= PNG_FLAG_ZSTREAM_INITIALIZED; |
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413 | } |
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414 | |||
415 | |||
416 | png_ptr->zowner = owner; |
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417 | |||
418 | |||
419 | png_zstream_error(png_ptr, ret); |
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420 | |||
421 | |||
422 | } |
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423 | |||
424 | |||
425 | # undef window_bits |
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426 | # endif |
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427 | } |
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428 | |||
429 | |||
430 | /* png_inflate now returns zlib error codes including Z_OK and Z_STREAM_END to |
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431 | * allow the caller to do multiple calls if required. If the 'finish' flag is |
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432 | * set Z_FINISH will be passed to the final inflate() call and Z_STREAM_END must |
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433 | * be returned or there has been a problem, otherwise Z_SYNC_FLUSH is used and |
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434 | * Z_OK or Z_STREAM_END will be returned on success. |
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435 | * |
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436 | * The input and output sizes are updated to the actual amounts of data consumed |
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437 | * or written, not the amount available (as in a z_stream). The data pointers |
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438 | * are not changed, so the next input is (data+input_size) and the next |
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439 | * available output is (output+output_size). |
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440 | */ |
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441 | static int |
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442 | png_inflate(png_structrp png_ptr, png_uint_32 owner, int finish, |
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443 | /* INPUT: */ png_const_bytep input, png_uint_32p input_size_ptr, |
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444 | /* OUTPUT: */ png_bytep output, png_alloc_size_t *output_size_ptr) |
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445 | { |
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446 | if (png_ptr->zowner == owner) /* Else not claimed */ |
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447 | { |
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448 | int ret; |
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449 | png_alloc_size_t avail_out = *output_size_ptr; |
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450 | png_uint_32 avail_in = *input_size_ptr; |
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451 | |||
452 | |||
453 | * can't even necessarily handle 65536 bytes) because the type uInt is |
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454 | * "16 bits or more". Consequently it is necessary to chunk the input to |
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455 | * zlib. This code uses ZLIB_IO_MAX, from pngpriv.h, as the maximum (the |
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456 | * maximum value that can be stored in a uInt.) It is possible to set |
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457 | * ZLIB_IO_MAX to a lower value in pngpriv.h and this may sometimes have |
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458 | * a performance advantage, because it reduces the amount of data accessed |
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459 | * at each step and that may give the OS more time to page it in. |
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460 | */ |
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461 | png_ptr->zstream.next_in = PNGZ_INPUT_CAST(input); |
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462 | /* avail_in and avail_out are set below from 'size' */ |
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463 | png_ptr->zstream.avail_in = 0; |
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464 | png_ptr->zstream.avail_out = 0; |
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465 | |||
466 | |||
467 | * a local buffer below if output is NULL). |
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468 | */ |
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469 | if (output != NULL) |
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470 | png_ptr->zstream.next_out = output; |
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471 | |||
472 | |||
473 | { |
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474 | uInt avail; |
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475 | Byte local_buffer[PNG_INFLATE_BUF_SIZE]; |
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476 | |||
477 | |||
478 | /* The setting of 'avail_in' used to be outside the loop; by setting it |
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479 | * inside it is possible to chunk the input to zlib and simply rely on |
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480 | * zlib to advance the 'next_in' pointer. This allows arbitrary |
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481 | * amounts of data to be passed through zlib at the unavoidable cost of |
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482 | * requiring a window save (memcpy of up to 32768 output bytes) |
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483 | * every ZLIB_IO_MAX input bytes. |
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484 | */ |
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485 | avail_in += png_ptr->zstream.avail_in; /* not consumed last time */ |
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486 | |||
487 | |||
488 | |||
489 | |||
490 | avail = (uInt)avail_in; /* safe: < than ZLIB_IO_MAX */ |
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491 | |||
492 | |||
493 | png_ptr->zstream.avail_in = avail; |
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494 | |||
495 | |||
496 | avail_out += png_ptr->zstream.avail_out; /* not written last time */ |
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497 | |||
498 | |||
499 | |||
500 | |||
501 | { |
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502 | /* Reset the output buffer each time round if output is NULL and |
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503 | * make available the full buffer, up to 'remaining_space' |
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504 | */ |
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505 | png_ptr->zstream.next_out = local_buffer; |
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506 | if ((sizeof local_buffer) < avail) |
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507 | avail = (sizeof local_buffer); |
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508 | } |
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509 | |||
510 | |||
511 | avail = (uInt)avail_out; /* safe: < ZLIB_IO_MAX */ |
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512 | |||
513 | |||
514 | avail_out -= avail; |
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515 | |||
516 | |||
517 | /* In fact 'avail_out' may be 0 at this point, that happens at the end |
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518 | * of the read when the final LZ end code was not passed at the end of |
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519 | * the previous chunk of input data. Tell zlib if we have reached the |
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520 | * end of the output buffer. |
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521 | */ |
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522 | ret = inflate(&png_ptr->zstream, avail_out > 0 ? Z_NO_FLUSH : |
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523 | (finish ? Z_FINISH : Z_SYNC_FLUSH)); |
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524 | } while (ret == Z_OK); |
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525 | |||
526 | |||
527 | if (output == NULL) |
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528 | png_ptr->zstream.next_out = NULL; |
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529 | |||
530 | |||
531 | avail_in += png_ptr->zstream.avail_in; |
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532 | avail_out += png_ptr->zstream.avail_out; |
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533 | |||
534 | |||
535 | * consumed or written, effectively the inverse of what zlib uses. |
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536 | */ |
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537 | if (avail_out > 0) |
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538 | *output_size_ptr -= avail_out; |
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539 | |||
540 | |||
541 | *input_size_ptr -= avail_in; |
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542 | |||
543 | |||
544 | png_zstream_error(png_ptr, ret); |
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545 | return ret; |
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546 | } |
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547 | |||
548 | |||
549 | { |
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550 | /* This is a bad internal error. The recovery assigns to the zstream msg |
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551 | * pointer, which is not owned by the caller, but this is safe; it's only |
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552 | * used on errors! |
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553 | */ |
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554 | png_ptr->zstream.msg = PNGZ_MSG_CAST("zstream unclaimed"); |
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555 | return Z_STREAM_ERROR; |
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556 | } |
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557 | } |
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558 | |||
559 | |||
560 | * Decompress trailing data in a chunk. The assumption is that read_buffer |
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561 | * points at an allocated area holding the contents of a chunk with a |
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562 | * trailing compressed part. What we get back is an allocated area |
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563 | * holding the original prefix part and an uncompressed version of the |
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564 | * trailing part (the malloc area passed in is freed). |
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565 | */ |
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566 | static int |
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567 | png_decompress_chunk(png_structrp png_ptr, |
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568 | png_uint_32 chunklength, png_uint_32 prefix_size, |
||
569 | png_alloc_size_t *newlength /* must be initialized to the maximum! */, |
||
570 | int terminate /*add a '\0' to the end of the uncompressed data*/) |
||
571 | { |
||
572 | /* TODO: implement different limits for different types of chunk. |
||
573 | * |
||
574 | * The caller supplies *newlength set to the maximum length of the |
||
575 | * uncompressed data, but this routine allocates space for the prefix and |
||
576 | * maybe a '\0' terminator too. We have to assume that 'prefix_size' is |
||
577 | * limited only by the maximum chunk size. |
||
578 | */ |
||
579 | png_alloc_size_t limit = PNG_SIZE_MAX; |
||
580 | |||
581 | |||
582 | if (png_ptr->user_chunk_malloc_max > 0 && |
||
583 | png_ptr->user_chunk_malloc_max < limit) |
||
584 | limit = png_ptr->user_chunk_malloc_max; |
||
585 | # elif PNG_USER_CHUNK_MALLOC_MAX > 0 |
||
586 | if (PNG_USER_CHUNK_MALLOC_MAX < limit) |
||
587 | limit = PNG_USER_CHUNK_MALLOC_MAX; |
||
588 | # endif |
||
589 | |||
590 | |||
591 | { |
||
592 | int ret; |
||
593 | |||
594 | |||
595 | |||
596 | |||
597 | *newlength = limit; |
||
598 | |||
599 | |||
600 | ret = png_inflate_claim(png_ptr, png_ptr->chunk_name); |
||
601 | |||
602 | |||
603 | { |
||
604 | png_uint_32 lzsize = chunklength - prefix_size; |
||
605 | |||
606 | |||
607 | /* input: */ png_ptr->read_buffer + prefix_size, &lzsize, |
||
608 | /* output: */ NULL, newlength); |
||
609 | |||
610 | |||
611 | { |
||
612 | /* Use 'inflateReset' here, not 'inflateReset2' because this |
||
613 | * preserves the previously decided window size (otherwise it would |
||
614 | * be necessary to store the previous window size.) In practice |
||
615 | * this doesn't matter anyway, because png_inflate will call inflate |
||
616 | * with Z_FINISH in almost all cases, so the window will not be |
||
617 | * maintained. |
||
618 | */ |
||
619 | if (inflateReset(&png_ptr->zstream) == Z_OK) |
||
620 | { |
||
621 | /* Because of the limit checks above we know that the new, |
||
622 | * expanded, size will fit in a size_t (let alone an |
||
623 | * png_alloc_size_t). Use png_malloc_base here to avoid an |
||
624 | * extra OOM message. |
||
625 | */ |
||
626 | png_alloc_size_t new_size = *newlength; |
||
627 | png_alloc_size_t buffer_size = prefix_size + new_size + |
||
628 | (terminate != 0); |
||
629 | png_bytep text = png_voidcast(png_bytep, png_malloc_base(png_ptr, |
||
630 | buffer_size)); |
||
631 | |||
632 | |||
633 | { |
||
634 | ret = png_inflate(png_ptr, png_ptr->chunk_name, 1/*finish*/, |
||
635 | png_ptr->read_buffer + prefix_size, &lzsize, |
||
636 | text + prefix_size, newlength); |
||
637 | |||
638 | |||
639 | { |
||
640 | if (new_size == *newlength) |
||
641 | { |
||
642 | if (terminate) |
||
643 | text[prefix_size + *newlength] = 0; |
||
644 | |||
645 | |||
646 | memcpy(text, png_ptr->read_buffer, prefix_size); |
||
647 | |||
648 | |||
649 | png_bytep old_ptr = png_ptr->read_buffer; |
||
650 | |||
651 | |||
652 | png_ptr->read_buffer_size = buffer_size; |
||
653 | text = old_ptr; /* freed below */ |
||
654 | } |
||
655 | } |
||
656 | |||
657 | |||
658 | { |
||
659 | /* The size changed on the second read, there can be no |
||
660 | * guarantee that anything is correct at this point. |
||
661 | * The 'msg' pointer has been set to "unexpected end of |
||
662 | * LZ stream", which is fine, but return an error code |
||
663 | * that the caller won't accept. |
||
664 | */ |
||
665 | ret = PNG_UNEXPECTED_ZLIB_RETURN; |
||
666 | } |
||
667 | } |
||
668 | |||
669 | |||
670 | ret = PNG_UNEXPECTED_ZLIB_RETURN; /* for safety */ |
||
671 | |||
672 | |||
673 | * success) |
||
674 | */ |
||
675 | png_free(png_ptr, text); |
||
676 | |||
677 | |||
678 | * the extra space may otherwise be used as a Trojan Horse. |
||
679 | */ |
||
680 | if (ret == Z_STREAM_END && |
||
681 | chunklength - prefix_size != lzsize) |
||
682 | png_chunk_benign_error(png_ptr, "extra compressed data"); |
||
683 | } |
||
684 | |||
685 | |||
686 | { |
||
687 | /* Out of memory allocating the buffer */ |
||
688 | ret = Z_MEM_ERROR; |
||
689 | png_zstream_error(png_ptr, Z_MEM_ERROR); |
||
690 | } |
||
691 | } |
||
692 | |||
693 | |||
694 | { |
||
695 | /* inflateReset failed, store the error message */ |
||
696 | png_zstream_error(png_ptr, ret); |
||
697 | |||
698 | |||
699 | ret = PNG_UNEXPECTED_ZLIB_RETURN; |
||
700 | } |
||
701 | } |
||
702 | |||
703 | |||
704 | ret = PNG_UNEXPECTED_ZLIB_RETURN; |
||
705 | |||
706 | |||
707 | png_ptr->zowner = 0; |
||
708 | } |
||
709 | |||
710 | |||
711 | ret = PNG_UNEXPECTED_ZLIB_RETURN; |
||
712 | |||
713 | |||
714 | } |
||
715 | |||
716 | |||
717 | { |
||
718 | /* Application/configuration limits exceeded */ |
||
719 | png_zstream_error(png_ptr, Z_MEM_ERROR); |
||
720 | return Z_MEM_ERROR; |
||
721 | } |
||
722 | } |
||
723 | #endif /* PNG_READ_COMPRESSED_TEXT_SUPPORTED */ |
||
724 | |||
725 | |||
726 | /* Perform a partial read and decompress, producing 'avail_out' bytes and |
||
727 | * reading from the current chunk as required. |
||
728 | */ |
||
729 | static int |
||
730 | png_inflate_read(png_structrp png_ptr, png_bytep read_buffer, uInt read_size, |
||
731 | png_uint_32p chunk_bytes, png_bytep next_out, png_alloc_size_t *out_size, |
||
732 | int finish) |
||
733 | { |
||
734 | if (png_ptr->zowner == png_ptr->chunk_name) |
||
735 | { |
||
736 | int ret; |
||
737 | |||
738 | |||
739 | png_ptr->zstream.next_out = next_out; |
||
740 | png_ptr->zstream.avail_out = 0; /* set in the loop */ |
||
741 | |||
742 | |||
743 | { |
||
744 | if (png_ptr->zstream.avail_in == 0) |
||
745 | { |
||
746 | if (read_size > *chunk_bytes) |
||
747 | read_size = (uInt)*chunk_bytes; |
||
748 | *chunk_bytes -= read_size; |
||
749 | |||
750 | |||
751 | png_crc_read(png_ptr, read_buffer, read_size); |
||
752 | |||
753 | |||
754 | png_ptr->zstream.avail_in = read_size; |
||
755 | } |
||
756 | |||
757 | |||
758 | { |
||
759 | uInt avail = ZLIB_IO_MAX; |
||
760 | if (avail > *out_size) |
||
761 | avail = (uInt)*out_size; |
||
762 | *out_size -= avail; |
||
763 | |||
764 | |||
765 | } |
||
766 | |||
767 | |||
768 | * the available output is produced; this allows reading of truncated |
||
769 | * streams. |
||
770 | */ |
||
771 | ret = inflate(&png_ptr->zstream, |
||
772 | *chunk_bytes > 0 ? Z_NO_FLUSH : (finish ? Z_FINISH : Z_SYNC_FLUSH)); |
||
773 | } |
||
774 | while (ret == Z_OK && (*out_size > 0 || png_ptr->zstream.avail_out > 0)); |
||
775 | |||
776 | |||
777 | png_ptr->zstream.avail_out = 0; /* Should not be required, but is safe */ |
||
778 | |||
779 | |||
780 | png_zstream_error(png_ptr, ret); |
||
781 | return ret; |
||
782 | } |
||
783 | |||
784 | |||
785 | { |
||
786 | png_ptr->zstream.msg = PNGZ_MSG_CAST("zstream unclaimed"); |
||
787 | return Z_STREAM_ERROR; |
||
788 | } |
||
789 | } |
||
790 | #endif |
||
791 | |||
792 | |||
793 | void /* PRIVATE */ |
||
794 | png_handle_IHDR(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
795 | { |
||
796 | png_byte buf[13]; |
||
797 | png_uint_32 width, height; |
||
798 | int bit_depth, color_type, compression_type, filter_type; |
||
799 | int interlace_type; |
||
800 | |||
801 | |||
802 | |||
803 | |||
804 | png_chunk_error(png_ptr, "out of place"); |
||
805 | |||
806 | |||
807 | if (length != 13) |
||
808 | png_chunk_error(png_ptr, "invalid"); |
||
809 | |||
810 | |||
811 | |||
812 | |||
813 | png_crc_finish(png_ptr, 0); |
||
814 | |||
815 | |||
816 | height = png_get_uint_31(png_ptr, buf + 4); |
||
817 | bit_depth = buf[8]; |
||
818 | color_type = buf[9]; |
||
819 | compression_type = buf[10]; |
||
820 | filter_type = buf[11]; |
||
821 | interlace_type = buf[12]; |
||
822 | |||
823 | |||
824 | png_ptr->width = width; |
||
825 | png_ptr->height = height; |
||
826 | png_ptr->bit_depth = (png_byte)bit_depth; |
||
827 | png_ptr->interlaced = (png_byte)interlace_type; |
||
828 | png_ptr->color_type = (png_byte)color_type; |
||
829 | #ifdef PNG_MNG_FEATURES_SUPPORTED |
||
830 | png_ptr->filter_type = (png_byte)filter_type; |
||
831 | #endif |
||
832 | png_ptr->compression_type = (png_byte)compression_type; |
||
833 | |||
834 | |||
835 | switch (png_ptr->color_type) |
||
836 | { |
||
837 | default: /* invalid, png_set_IHDR calls png_error */ |
||
838 | case PNG_COLOR_TYPE_GRAY: |
||
839 | case PNG_COLOR_TYPE_PALETTE: |
||
840 | png_ptr->channels = 1; |
||
841 | break; |
||
842 | |||
843 | |||
844 | png_ptr->channels = 3; |
||
845 | break; |
||
846 | |||
847 | |||
848 | png_ptr->channels = 2; |
||
849 | break; |
||
850 | |||
851 | |||
852 | png_ptr->channels = 4; |
||
853 | break; |
||
854 | } |
||
855 | |||
856 | |||
857 | png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth * |
||
858 | png_ptr->channels); |
||
859 | png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width); |
||
860 | png_debug1(3, "bit_depth = %d", png_ptr->bit_depth); |
||
861 | png_debug1(3, "channels = %d", png_ptr->channels); |
||
862 | png_debug1(3, "rowbytes = %lu", (unsigned long)png_ptr->rowbytes); |
||
863 | png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, |
||
864 | color_type, interlace_type, compression_type, filter_type); |
||
865 | } |
||
866 | |||
867 | |||
868 | void /* PRIVATE */ |
||
869 | png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
870 | { |
||
871 | png_color palette[PNG_MAX_PALETTE_LENGTH]; |
||
872 | int num, i; |
||
873 | #ifdef PNG_POINTER_INDEXING_SUPPORTED |
||
874 | png_colorp pal_ptr; |
||
875 | #endif |
||
876 | |||
877 | |||
878 | |||
879 | |||
880 | png_chunk_error(png_ptr, "missing IHDR"); |
||
881 | |||
882 | |||
883 | * PLTE chunks are potentially ignored (the spec says there shall not be more |
||
884 | * than one PLTE, the error is not treated as benign, so this check trumps |
||
885 | * the requirement that PLTE appears before IDAT.) |
||
886 | */ |
||
887 | else if (png_ptr->mode & PNG_HAVE_PLTE) |
||
888 | png_chunk_error(png_ptr, "duplicate"); |
||
889 | |||
890 | |||
891 | { |
||
892 | /* This is benign because the non-benign error happened before, when an |
||
893 | * IDAT was encountered in a color-mapped image with no PLTE. |
||
894 | */ |
||
895 | png_crc_finish(png_ptr, length); |
||
896 | png_chunk_benign_error(png_ptr, "out of place"); |
||
897 | return; |
||
898 | } |
||
899 | |||
900 | |||
901 | |||
902 | |||
903 | { |
||
904 | png_crc_finish(png_ptr, length); |
||
905 | png_chunk_benign_error(png_ptr, "ignored in grayscale PNG"); |
||
906 | return; |
||
907 | } |
||
908 | |||
909 | |||
910 | if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE) |
||
911 | { |
||
912 | png_crc_finish(png_ptr, length); |
||
913 | return; |
||
914 | } |
||
915 | #endif |
||
916 | |||
917 | |||
918 | { |
||
919 | png_crc_finish(png_ptr, length); |
||
920 | |||
921 | |||
922 | png_chunk_benign_error(png_ptr, "invalid"); |
||
923 | |||
924 | |||
925 | png_chunk_error(png_ptr, "invalid"); |
||
926 | |||
927 | |||
928 | } |
||
929 | |||
930 | |||
931 | num = (int)length / 3; |
||
932 | |||
933 | |||
934 | for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++) |
||
935 | { |
||
936 | png_byte buf[3]; |
||
937 | |||
938 | |||
939 | pal_ptr->red = buf[0]; |
||
940 | pal_ptr->green = buf[1]; |
||
941 | pal_ptr->blue = buf[2]; |
||
942 | } |
||
943 | #else |
||
944 | for (i = 0; i < num; i++) |
||
945 | { |
||
946 | png_byte buf[3]; |
||
947 | |||
948 | |||
949 | /* Don't depend upon png_color being any order */ |
||
950 | palette[i].red = buf[0]; |
||
951 | palette[i].green = buf[1]; |
||
952 | palette[i].blue = buf[2]; |
||
953 | } |
||
954 | #endif |
||
955 | |||
956 | |||
957 | * whatever the normal CRC configuration tells us. However, if we |
||
958 | * have an RGB image, the PLTE can be considered ancillary, so |
||
959 | * we will act as though it is. |
||
960 | */ |
||
961 | #ifndef PNG_READ_OPT_PLTE_SUPPORTED |
||
962 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
||
963 | #endif |
||
964 | { |
||
965 | png_crc_finish(png_ptr, 0); |
||
966 | } |
||
967 | |||
968 | |||
969 | else if (png_crc_error(png_ptr)) /* Only if we have a CRC error */ |
||
970 | { |
||
971 | /* If we don't want to use the data from an ancillary chunk, |
||
972 | * we have two options: an error abort, or a warning and we |
||
973 | * ignore the data in this chunk (which should be OK, since |
||
974 | * it's considered ancillary for a RGB or RGBA image). |
||
975 | * |
||
976 | * IMPLEMENTATION NOTE: this is only here because png_crc_finish uses the |
||
977 | * chunk type to determine whether to check the ancillary or the critical |
||
978 | * flags. |
||
979 | */ |
||
980 | if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE)) |
||
981 | { |
||
982 | if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) |
||
983 | { |
||
984 | png_chunk_benign_error(png_ptr, "CRC error"); |
||
985 | } |
||
986 | |||
987 | |||
988 | { |
||
989 | png_chunk_warning(png_ptr, "CRC error"); |
||
990 | return; |
||
991 | } |
||
992 | } |
||
993 | |||
994 | |||
995 | else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) |
||
996 | { |
||
997 | png_chunk_warning(png_ptr, "CRC error"); |
||
998 | } |
||
999 | } |
||
1000 | #endif |
||
1001 | |||
1002 | |||
1003 | * own copy of the palette. This has the side effect that when png_start_row |
||
1004 | * is called (this happens after any call to png_read_update_info) the |
||
1005 | * info_ptr palette gets changed. This is extremely unexpected and |
||
1006 | * confusing. |
||
1007 | * |
||
1008 | * Fix this by not sharing the palette in this way. |
||
1009 | */ |
||
1010 | png_set_PLTE(png_ptr, info_ptr, palette, num); |
||
1011 | |||
1012 | |||
1013 | * IDAT. Prior to 1.6.0 this was not checked; instead the code merely |
||
1014 | * checked the apparent validity of a tRNS chunk inserted before PLTE on a |
||
1015 | * palette PNG. 1.6.0 attempts to rigorously follow the standard and |
||
1016 | * therefore does a benign error if the erroneous condition is detected *and* |
||
1017 | * cancels the tRNS if the benign error returns. The alternative is to |
||
1018 | * amend the standard since it would be rather hypocritical of the standards |
||
1019 | * maintainers to ignore it. |
||
1020 | */ |
||
1021 | #ifdef PNG_READ_tRNS_SUPPORTED |
||
1022 | if (png_ptr->num_trans > 0 || |
||
1023 | (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS) != 0)) |
||
1024 | { |
||
1025 | /* Cancel this because otherwise it would be used if the transforms |
||
1026 | * require it. Don't cancel the 'valid' flag because this would prevent |
||
1027 | * detection of duplicate chunks. |
||
1028 | */ |
||
1029 | png_ptr->num_trans = 0; |
||
1030 | |||
1031 | |||
1032 | info_ptr->num_trans = 0; |
||
1033 | |||
1034 | |||
1035 | } |
||
1036 | #endif |
||
1037 | |||
1038 | |||
1039 | if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST) != 0) |
||
1040 | png_chunk_benign_error(png_ptr, "hIST must be after"); |
||
1041 | #endif |
||
1042 | |||
1043 | |||
1044 | if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD) != 0) |
||
1045 | png_chunk_benign_error(png_ptr, "bKGD must be after"); |
||
1046 | #endif |
||
1047 | } |
||
1048 | |||
1049 | |||
1050 | png_handle_IEND(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1051 | { |
||
1052 | png_debug(1, "in png_handle_IEND"); |
||
1053 | |||
1054 | |||
1055 | png_chunk_error(png_ptr, "out of place"); |
||
1056 | |||
1057 | |||
1058 | |||
1059 | |||
1060 | |||
1061 | |||
1062 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1063 | |||
1064 | |||
1065 | } |
||
1066 | |||
1067 | |||
1068 | void /* PRIVATE */ |
||
1069 | png_handle_gAMA(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1070 | { |
||
1071 | png_fixed_point igamma; |
||
1072 | png_byte buf[4]; |
||
1073 | |||
1074 | |||
1075 | |||
1076 | |||
1077 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1078 | |||
1079 | |||
1080 | { |
||
1081 | png_crc_finish(png_ptr, length); |
||
1082 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1083 | return; |
||
1084 | } |
||
1085 | |||
1086 | |||
1087 | { |
||
1088 | png_crc_finish(png_ptr, length); |
||
1089 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1090 | return; |
||
1091 | } |
||
1092 | |||
1093 | |||
1094 | |||
1095 | |||
1096 | return; |
||
1097 | |||
1098 | |||
1099 | |||
1100 | |||
1101 | png_colorspace_sync(png_ptr, info_ptr); |
||
1102 | } |
||
1103 | #endif |
||
1104 | |||
1105 | |||
1106 | void /* PRIVATE */ |
||
1107 | png_handle_sBIT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1108 | { |
||
1109 | unsigned int truelen; |
||
1110 | png_byte buf[4]; |
||
1111 | |||
1112 | |||
1113 | |||
1114 | |||
1115 | |||
1116 | |||
1117 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1118 | |||
1119 | |||
1120 | { |
||
1121 | png_crc_finish(png_ptr, length); |
||
1122 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1123 | return; |
||
1124 | } |
||
1125 | |||
1126 | |||
1127 | { |
||
1128 | png_crc_finish(png_ptr, length); |
||
1129 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
1130 | return; |
||
1131 | } |
||
1132 | |||
1133 | |||
1134 | truelen = 3; |
||
1135 | |||
1136 | |||
1137 | truelen = png_ptr->channels; |
||
1138 | |||
1139 | |||
1140 | { |
||
1141 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1142 | png_crc_finish(png_ptr, length); |
||
1143 | return; |
||
1144 | } |
||
1145 | |||
1146 | |||
1147 | |||
1148 | |||
1149 | return; |
||
1150 | |||
1151 | |||
1152 | { |
||
1153 | png_ptr->sig_bit.red = buf[0]; |
||
1154 | png_ptr->sig_bit.green = buf[1]; |
||
1155 | png_ptr->sig_bit.blue = buf[2]; |
||
1156 | png_ptr->sig_bit.alpha = buf[3]; |
||
1157 | } |
||
1158 | |||
1159 | |||
1160 | { |
||
1161 | png_ptr->sig_bit.gray = buf[0]; |
||
1162 | png_ptr->sig_bit.red = buf[0]; |
||
1163 | png_ptr->sig_bit.green = buf[0]; |
||
1164 | png_ptr->sig_bit.blue = buf[0]; |
||
1165 | png_ptr->sig_bit.alpha = buf[1]; |
||
1166 | } |
||
1167 | |||
1168 | |||
1169 | } |
||
1170 | #endif |
||
1171 | |||
1172 | |||
1173 | void /* PRIVATE */ |
||
1174 | png_handle_cHRM(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1175 | { |
||
1176 | png_byte buf[32]; |
||
1177 | png_xy xy; |
||
1178 | |||
1179 | |||
1180 | |||
1181 | |||
1182 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1183 | |||
1184 | |||
1185 | { |
||
1186 | png_crc_finish(png_ptr, length); |
||
1187 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1188 | return; |
||
1189 | } |
||
1190 | |||
1191 | |||
1192 | { |
||
1193 | png_crc_finish(png_ptr, length); |
||
1194 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1195 | return; |
||
1196 | } |
||
1197 | |||
1198 | |||
1199 | |||
1200 | |||
1201 | return; |
||
1202 | |||
1203 | |||
1204 | xy.whitey = png_get_fixed_point(NULL, buf + 4); |
||
1205 | xy.redx = png_get_fixed_point(NULL, buf + 8); |
||
1206 | xy.redy = png_get_fixed_point(NULL, buf + 12); |
||
1207 | xy.greenx = png_get_fixed_point(NULL, buf + 16); |
||
1208 | xy.greeny = png_get_fixed_point(NULL, buf + 20); |
||
1209 | xy.bluex = png_get_fixed_point(NULL, buf + 24); |
||
1210 | xy.bluey = png_get_fixed_point(NULL, buf + 28); |
||
1211 | |||
1212 | |||
1213 | xy.whitey == PNG_FIXED_ERROR || |
||
1214 | xy.redx == PNG_FIXED_ERROR || |
||
1215 | xy.redy == PNG_FIXED_ERROR || |
||
1216 | xy.greenx == PNG_FIXED_ERROR || |
||
1217 | xy.greeny == PNG_FIXED_ERROR || |
||
1218 | xy.bluex == PNG_FIXED_ERROR || |
||
1219 | xy.bluey == PNG_FIXED_ERROR) |
||
1220 | { |
||
1221 | png_chunk_benign_error(png_ptr, "invalid values"); |
||
1222 | return; |
||
1223 | } |
||
1224 | |||
1225 | |||
1226 | if (png_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) |
||
1227 | return; |
||
1228 | |||
1229 | |||
1230 | { |
||
1231 | png_ptr->colorspace.flags |= PNG_COLORSPACE_INVALID; |
||
1232 | png_colorspace_sync(png_ptr, info_ptr); |
||
1233 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
1234 | return; |
||
1235 | } |
||
1236 | |||
1237 | |||
1238 | (void)png_colorspace_set_chromaticities(png_ptr, &png_ptr->colorspace, &xy, |
||
1239 | 1/*prefer cHRM values*/); |
||
1240 | png_colorspace_sync(png_ptr, info_ptr); |
||
1241 | } |
||
1242 | #endif |
||
1243 | |||
1244 | |||
1245 | void /* PRIVATE */ |
||
1246 | png_handle_sRGB(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1247 | { |
||
1248 | png_byte intent; |
||
1249 | |||
1250 | |||
1251 | |||
1252 | |||
1253 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1254 | |||
1255 | |||
1256 | { |
||
1257 | png_crc_finish(png_ptr, length); |
||
1258 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1259 | return; |
||
1260 | } |
||
1261 | |||
1262 | |||
1263 | { |
||
1264 | png_crc_finish(png_ptr, length); |
||
1265 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1266 | return; |
||
1267 | } |
||
1268 | |||
1269 | |||
1270 | |||
1271 | |||
1272 | return; |
||
1273 | |||
1274 | |||
1275 | if (png_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) |
||
1276 | return; |
||
1277 | |||
1278 | |||
1279 | * this. |
||
1280 | */ |
||
1281 | if (png_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_INTENT) |
||
1282 | { |
||
1283 | png_ptr->colorspace.flags |= PNG_COLORSPACE_INVALID; |
||
1284 | png_colorspace_sync(png_ptr, info_ptr); |
||
1285 | png_chunk_benign_error(png_ptr, "too many profiles"); |
||
1286 | return; |
||
1287 | } |
||
1288 | |||
1289 | |||
1290 | png_colorspace_sync(png_ptr, info_ptr); |
||
1291 | } |
||
1292 | #endif /* PNG_READ_sRGB_SUPPORTED */ |
||
1293 | |||
1294 | |||
1295 | void /* PRIVATE */ |
||
1296 | png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1297 | /* Note: this does not properly handle profiles that are > 64K under DOS */ |
||
1298 | { |
||
1299 | png_const_charp errmsg = NULL; /* error message output, or no error */ |
||
1300 | int finished = 0; /* crc checked */ |
||
1301 | |||
1302 | |||
1303 | |||
1304 | |||
1305 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1306 | |||
1307 | |||
1308 | { |
||
1309 | png_crc_finish(png_ptr, length); |
||
1310 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1311 | return; |
||
1312 | } |
||
1313 | |||
1314 | |||
1315 | * chunk is just ignored, so does not invalidate the color space. An |
||
1316 | * alternative is to set the 'invalid' flags at the start of this routine |
||
1317 | * and only clear them in they were not set before and all the tests pass. |
||
1318 | * The minimum 'deflate' stream is assumed to be just the 2 byte header and 4 |
||
1319 | * byte checksum. The keyword must be one character and there is a |
||
1320 | * terminator (0) byte and the compression method. |
||
1321 | */ |
||
1322 | if (length < 9) |
||
1323 | { |
||
1324 | png_crc_finish(png_ptr, length); |
||
1325 | png_chunk_benign_error(png_ptr, "too short"); |
||
1326 | return; |
||
1327 | } |
||
1328 | |||
1329 | |||
1330 | if (png_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) |
||
1331 | { |
||
1332 | png_crc_finish(png_ptr, length); |
||
1333 | return; |
||
1334 | } |
||
1335 | |||
1336 | |||
1337 | * this. |
||
1338 | */ |
||
1339 | if ((png_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_INTENT) == 0) |
||
1340 | { |
||
1341 | uInt read_length, keyword_length; |
||
1342 | char keyword[81]; |
||
1343 | |||
1344 | |||
1345 | * bytes can be at most 81 characters long. |
||
1346 | */ |
||
1347 | read_length = 81; /* maximum */ |
||
1348 | if (read_length > length) |
||
1349 | read_length = (uInt)length; |
||
1350 | |||
1351 | |||
1352 | length -= read_length; |
||
1353 | |||
1354 | |||
1355 | while (keyword_length < 80 && keyword_length < read_length && |
||
1356 | keyword[keyword_length] != 0) |
||
1357 | ++keyword_length; |
||
1358 | |||
1359 | |||
1360 | if (keyword_length >= 1 && keyword_length <= 79) |
||
1361 | { |
||
1362 | /* We only understand '0' compression - deflate - so if we get a |
||
1363 | * different value we can't safely decode the chunk. |
||
1364 | */ |
||
1365 | if (keyword_length+1 < read_length && |
||
1366 | keyword[keyword_length+1] == PNG_COMPRESSION_TYPE_BASE) |
||
1367 | { |
||
1368 | read_length -= keyword_length+2; |
||
1369 | |||
1370 | |||
1371 | { |
||
1372 | Byte profile_header[132]; |
||
1373 | Byte local_buffer[PNG_INFLATE_BUF_SIZE]; |
||
1374 | png_alloc_size_t size = (sizeof profile_header); |
||
1375 | |||
1376 | |||
1377 | png_ptr->zstream.avail_in = read_length; |
||
1378 | (void)png_inflate_read(png_ptr, local_buffer, |
||
1379 | (sizeof local_buffer), &length, profile_header, &size, |
||
1380 | 0/*finish: don't, because the output is too small*/); |
||
1381 | |||
1382 | |||
1383 | { |
||
1384 | /* We have the ICC profile header; do the basic header checks. |
||
1385 | */ |
||
1386 | const png_uint_32 profile_length = |
||
1387 | png_get_uint_32(profile_header); |
||
1388 | |||
1389 | |||
1390 | keyword, profile_length)) |
||
1391 | { |
||
1392 | /* The length is apparently ok, so we can check the 132 |
||
1393 | * byte header. |
||
1394 | */ |
||
1395 | if (png_icc_check_header(png_ptr, &png_ptr->colorspace, |
||
1396 | keyword, profile_length, profile_header, |
||
1397 | png_ptr->color_type)) |
||
1398 | { |
||
1399 | /* Now read the tag table; a variable size buffer is |
||
1400 | * needed at this point, allocate one for the whole |
||
1401 | * profile. The header check has already validated |
||
1402 | * that none of these stuff will overflow. |
||
1403 | */ |
||
1404 | const png_uint_32 tag_count = png_get_uint_32( |
||
1405 | profile_header+128); |
||
1406 | png_bytep profile = png_read_buffer(png_ptr, |
||
1407 | profile_length, 2/*silent*/); |
||
1408 | |||
1409 | |||
1410 | { |
||
1411 | memcpy(profile, profile_header, |
||
1412 | (sizeof profile_header)); |
||
1413 | |||
1414 | |||
1415 | |||
1416 | |||
1417 | (sizeof local_buffer), &length, |
||
1418 | profile + (sizeof profile_header), &size, 0); |
||
1419 | |||
1420 | |||
1421 | * there to be some tag data! |
||
1422 | */ |
||
1423 | if (size == 0) |
||
1424 | { |
||
1425 | if (png_icc_check_tag_table(png_ptr, |
||
1426 | &png_ptr->colorspace, keyword, profile_length, |
||
1427 | profile)) |
||
1428 | { |
||
1429 | /* The profile has been validated for basic |
||
1430 | * security issues, so read the whole thing in. |
||
1431 | */ |
||
1432 | size = profile_length - (sizeof profile_header) |
||
1433 | - 12 * tag_count; |
||
1434 | |||
1435 | |||
1436 | (sizeof local_buffer), &length, |
||
1437 | profile + (sizeof profile_header) + |
||
1438 | 12 * tag_count, &size, 1/*finish*/); |
||
1439 | |||
1440 | |||
1441 | PNG_FLAG_BENIGN_ERRORS_WARN)) |
||
1442 | errmsg = "extra compressed data"; |
||
1443 | |||
1444 | |||
1445 | else if (size == 0) |
||
1446 | { |
||
1447 | if (length > 0) |
||
1448 | { |
||
1449 | /* This can be handled completely, so |
||
1450 | * keep going. |
||
1451 | */ |
||
1452 | png_chunk_warning(png_ptr, |
||
1453 | "extra compressed data"); |
||
1454 | } |
||
1455 | |||
1456 | |||
1457 | finished = 1; |
||
1458 | |||
1459 | |||
1460 | /* Check for a match against sRGB */ |
||
1461 | png_icc_set_sRGB(png_ptr, |
||
1462 | &png_ptr->colorspace, profile, |
||
1463 | png_ptr->zstream.adler); |
||
1464 | # endif |
||
1465 | |||
1466 | |||
1467 | if (info_ptr != NULL) |
||
1468 | { |
||
1469 | png_free_data(png_ptr, info_ptr, |
||
1470 | PNG_FREE_ICCP, 0); |
||
1471 | |||
1472 | |||
1473 | png_malloc_base(png_ptr, |
||
1474 | keyword_length+1)); |
||
1475 | if (info_ptr->iccp_name != NULL) |
||
1476 | { |
||
1477 | memcpy(info_ptr->iccp_name, keyword, |
||
1478 | keyword_length+1); |
||
1479 | info_ptr->iccp_proflen = |
||
1480 | profile_length; |
||
1481 | info_ptr->iccp_profile = profile; |
||
1482 | png_ptr->read_buffer = NULL; /*steal*/ |
||
1483 | info_ptr->free_me |= PNG_FREE_ICCP; |
||
1484 | info_ptr->valid |= PNG_INFO_iCCP; |
||
1485 | } |
||
1486 | |||
1487 | |||
1488 | { |
||
1489 | png_ptr->colorspace.flags |= |
||
1490 | PNG_COLORSPACE_INVALID; |
||
1491 | errmsg = "out of memory"; |
||
1492 | } |
||
1493 | } |
||
1494 | |||
1495 | |||
1496 | * buffer which gets reused for subsequent |
||
1497 | * chunks. |
||
1498 | */ |
||
1499 | |||
1500 | |||
1501 | png_colorspace_sync(png_ptr, info_ptr); |
||
1502 | |||
1503 | |||
1504 | { |
||
1505 | png_ptr->zowner = 0; |
||
1506 | return; |
||
1507 | } |
||
1508 | } |
||
1509 | |||
1510 | |||
1511 | errmsg = "truncated"; |
||
1512 | |||
1513 | |||
1514 | errmsg = png_ptr->zstream.msg; |
||
1515 | } |
||
1516 | |||
1517 | |||
1518 | } |
||
1519 | |||
1520 | |||
1521 | errmsg = png_ptr->zstream.msg; |
||
1522 | } |
||
1523 | |||
1524 | |||
1525 | errmsg = "out of memory"; |
||
1526 | } |
||
1527 | |||
1528 | |||
1529 | } |
||
1530 | |||
1531 | |||
1532 | } |
||
1533 | |||
1534 | |||
1535 | errmsg = png_ptr->zstream.msg; |
||
1536 | |||
1537 | |||
1538 | png_ptr->zowner = 0; |
||
1539 | } |
||
1540 | |||
1541 | |||
1542 | errmsg = png_ptr->zstream.msg; |
||
1543 | } |
||
1544 | |||
1545 | |||
1546 | errmsg = "bad compression method"; /* or missing */ |
||
1547 | } |
||
1548 | |||
1549 | |||
1550 | errmsg = "bad keyword"; |
||
1551 | } |
||
1552 | |||
1553 | |||
1554 | errmsg = "too many profiles"; |
||
1555 | |||
1556 | |||
1557 | if (!finished) |
||
1558 | png_crc_finish(png_ptr, length); |
||
1559 | |||
1560 | |||
1561 | png_colorspace_sync(png_ptr, info_ptr); |
||
1562 | if (errmsg != NULL) /* else already output */ |
||
1563 | png_chunk_benign_error(png_ptr, errmsg); |
||
1564 | } |
||
1565 | #endif /* PNG_READ_iCCP_SUPPORTED */ |
||
1566 | |||
1567 | |||
1568 | void /* PRIVATE */ |
||
1569 | png_handle_sPLT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1570 | /* Note: this does not properly handle chunks that are > 64K under DOS */ |
||
1571 | { |
||
1572 | png_bytep entry_start, buffer; |
||
1573 | png_sPLT_t new_palette; |
||
1574 | png_sPLT_entryp pp; |
||
1575 | png_uint_32 data_length; |
||
1576 | int entry_size, i; |
||
1577 | png_uint_32 skip = 0; |
||
1578 | png_uint_32 dl; |
||
1579 | png_size_t max_dl; |
||
1580 | |||
1581 | |||
1582 | |||
1583 | |||
1584 | if (png_ptr->user_chunk_cache_max != 0) |
||
1585 | { |
||
1586 | if (png_ptr->user_chunk_cache_max == 1) |
||
1587 | { |
||
1588 | png_crc_finish(png_ptr, length); |
||
1589 | return; |
||
1590 | } |
||
1591 | |||
1592 | |||
1593 | { |
||
1594 | png_warning(png_ptr, "No space in chunk cache for sPLT"); |
||
1595 | png_crc_finish(png_ptr, length); |
||
1596 | return; |
||
1597 | } |
||
1598 | } |
||
1599 | #endif |
||
1600 | |||
1601 | |||
1602 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1603 | |||
1604 | |||
1605 | { |
||
1606 | png_crc_finish(png_ptr, length); |
||
1607 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1608 | return; |
||
1609 | } |
||
1610 | |||
1611 | |||
1612 | if (length > 65535U) |
||
1613 | { |
||
1614 | png_crc_finish(png_ptr, length); |
||
1615 | png_chunk_benign_error(png_ptr, "too large to fit in memory"); |
||
1616 | return; |
||
1617 | } |
||
1618 | #endif |
||
1619 | |||
1620 | |||
1621 | if (buffer == NULL) |
||
1622 | { |
||
1623 | png_crc_finish(png_ptr, length); |
||
1624 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
1625 | return; |
||
1626 | } |
||
1627 | |||
1628 | |||
1629 | |||
1630 | * that the PNG_MAX_MALLOC_64K test is enabled in this case, but this is a |
||
1631 | * potential breakage point if the types in pngconf.h aren't exactly right. |
||
1632 | */ |
||
1633 | png_crc_read(png_ptr, buffer, length); |
||
1634 | |||
1635 | |||
1636 | return; |
||
1637 | |||
1638 | |||
1639 | |||
1640 | |||
1641 | /* Empty loop to find end of name */ ; |
||
1642 | |||
1643 | |||
1644 | |||
1645 | |||
1646 | if (entry_start > buffer + length - 2) |
||
1647 | { |
||
1648 | png_warning(png_ptr, "malformed sPLT chunk"); |
||
1649 | return; |
||
1650 | } |
||
1651 | |||
1652 | |||
1653 | entry_size = (new_palette.depth == 8 ? 6 : 10); |
||
1654 | /* This must fit in a png_uint_32 because it is derived from the original |
||
1655 | * chunk data length. |
||
1656 | */ |
||
1657 | data_length = length - (png_uint_32)(entry_start - buffer); |
||
1658 | |||
1659 | |||
1660 | if (data_length % entry_size) |
||
1661 | { |
||
1662 | png_warning(png_ptr, "sPLT chunk has bad length"); |
||
1663 | return; |
||
1664 | } |
||
1665 | |||
1666 | |||
1667 | max_dl = PNG_SIZE_MAX / (sizeof (png_sPLT_entry)); |
||
1668 | |||
1669 | |||
1670 | { |
||
1671 | png_warning(png_ptr, "sPLT chunk too long"); |
||
1672 | return; |
||
1673 | } |
||
1674 | |||
1675 | |||
1676 | |||
1677 | |||
1678 | png_ptr, new_palette.nentries * (sizeof (png_sPLT_entry))); |
||
1679 | |||
1680 | |||
1681 | { |
||
1682 | png_warning(png_ptr, "sPLT chunk requires too much memory"); |
||
1683 | return; |
||
1684 | } |
||
1685 | |||
1686 | |||
1687 | for (i = 0; i < new_palette.nentries; i++) |
||
1688 | { |
||
1689 | pp = new_palette.entries + i; |
||
1690 | |||
1691 | |||
1692 | { |
||
1693 | pp->red = *entry_start++; |
||
1694 | pp->green = *entry_start++; |
||
1695 | pp->blue = *entry_start++; |
||
1696 | pp->alpha = *entry_start++; |
||
1697 | } |
||
1698 | |||
1699 | |||
1700 | { |
||
1701 | pp->red = png_get_uint_16(entry_start); entry_start += 2; |
||
1702 | pp->green = png_get_uint_16(entry_start); entry_start += 2; |
||
1703 | pp->blue = png_get_uint_16(entry_start); entry_start += 2; |
||
1704 | pp->alpha = png_get_uint_16(entry_start); entry_start += 2; |
||
1705 | } |
||
1706 | |||
1707 | |||
1708 | } |
||
1709 | #else |
||
1710 | pp = new_palette.entries; |
||
1711 | |||
1712 | |||
1713 | { |
||
1714 | |||
1715 | |||
1716 | { |
||
1717 | pp[i].red = *entry_start++; |
||
1718 | pp[i].green = *entry_start++; |
||
1719 | pp[i].blue = *entry_start++; |
||
1720 | pp[i].alpha = *entry_start++; |
||
1721 | } |
||
1722 | |||
1723 | |||
1724 | { |
||
1725 | pp[i].red = png_get_uint_16(entry_start); entry_start += 2; |
||
1726 | pp[i].green = png_get_uint_16(entry_start); entry_start += 2; |
||
1727 | pp[i].blue = png_get_uint_16(entry_start); entry_start += 2; |
||
1728 | pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2; |
||
1729 | } |
||
1730 | |||
1731 | |||
1732 | } |
||
1733 | #endif |
||
1734 | |||
1735 | |||
1736 | new_palette.name = (png_charp)buffer; |
||
1737 | |||
1738 | |||
1739 | |||
1740 | |||
1741 | } |
||
1742 | #endif /* PNG_READ_sPLT_SUPPORTED */ |
||
1743 | |||
1744 | |||
1745 | void /* PRIVATE */ |
||
1746 | png_handle_tRNS(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1747 | { |
||
1748 | png_byte readbuf[PNG_MAX_PALETTE_LENGTH]; |
||
1749 | |||
1750 | |||
1751 | |||
1752 | |||
1753 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1754 | |||
1755 | |||
1756 | { |
||
1757 | png_crc_finish(png_ptr, length); |
||
1758 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1759 | return; |
||
1760 | } |
||
1761 | |||
1762 | |||
1763 | { |
||
1764 | png_crc_finish(png_ptr, length); |
||
1765 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
1766 | return; |
||
1767 | } |
||
1768 | |||
1769 | |||
1770 | { |
||
1771 | png_byte buf[2]; |
||
1772 | |||
1773 | |||
1774 | { |
||
1775 | png_crc_finish(png_ptr, length); |
||
1776 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1777 | return; |
||
1778 | } |
||
1779 | |||
1780 | |||
1781 | png_ptr->num_trans = 1; |
||
1782 | png_ptr->trans_color.gray = png_get_uint_16(buf); |
||
1783 | } |
||
1784 | |||
1785 | |||
1786 | { |
||
1787 | png_byte buf[6]; |
||
1788 | |||
1789 | |||
1790 | { |
||
1791 | png_crc_finish(png_ptr, length); |
||
1792 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1793 | return; |
||
1794 | } |
||
1795 | |||
1796 | |||
1797 | png_ptr->num_trans = 1; |
||
1798 | png_ptr->trans_color.red = png_get_uint_16(buf); |
||
1799 | png_ptr->trans_color.green = png_get_uint_16(buf + 2); |
||
1800 | png_ptr->trans_color.blue = png_get_uint_16(buf + 4); |
||
1801 | } |
||
1802 | |||
1803 | |||
1804 | { |
||
1805 | if (!(png_ptr->mode & PNG_HAVE_PLTE)) |
||
1806 | { |
||
1807 | /* TODO: is this actually an error in the ISO spec? */ |
||
1808 | png_crc_finish(png_ptr, length); |
||
1809 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1810 | return; |
||
1811 | } |
||
1812 | |||
1813 | |||
1814 | length == 0) |
||
1815 | { |
||
1816 | png_crc_finish(png_ptr, length); |
||
1817 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1818 | return; |
||
1819 | } |
||
1820 | |||
1821 | |||
1822 | png_ptr->num_trans = (png_uint_16)length; |
||
1823 | } |
||
1824 | |||
1825 | |||
1826 | { |
||
1827 | png_crc_finish(png_ptr, length); |
||
1828 | png_chunk_benign_error(png_ptr, "invalid with alpha channel"); |
||
1829 | return; |
||
1830 | } |
||
1831 | |||
1832 | |||
1833 | { |
||
1834 | png_ptr->num_trans = 0; |
||
1835 | return; |
||
1836 | } |
||
1837 | |||
1838 | |||
1839 | * png_struct ends up with a pointer to the tRNS buffer owned by the |
||
1840 | * png_info. Fix this. |
||
1841 | */ |
||
1842 | png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans, |
||
1843 | &(png_ptr->trans_color)); |
||
1844 | } |
||
1845 | #endif |
||
1846 | |||
1847 | |||
1848 | void /* PRIVATE */ |
||
1849 | png_handle_bKGD(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1850 | { |
||
1851 | unsigned int truelen; |
||
1852 | png_byte buf[6]; |
||
1853 | png_color_16 background; |
||
1854 | |||
1855 | |||
1856 | |||
1857 | |||
1858 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1859 | |||
1860 | |||
1861 | (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
||
1862 | !(png_ptr->mode & PNG_HAVE_PLTE))) |
||
1863 | { |
||
1864 | png_crc_finish(png_ptr, length); |
||
1865 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1866 | return; |
||
1867 | } |
||
1868 | |||
1869 | |||
1870 | { |
||
1871 | png_crc_finish(png_ptr, length); |
||
1872 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
1873 | return; |
||
1874 | } |
||
1875 | |||
1876 | |||
1877 | truelen = 1; |
||
1878 | |||
1879 | |||
1880 | truelen = 6; |
||
1881 | |||
1882 | |||
1883 | truelen = 2; |
||
1884 | |||
1885 | |||
1886 | { |
||
1887 | png_crc_finish(png_ptr, length); |
||
1888 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1889 | return; |
||
1890 | } |
||
1891 | |||
1892 | |||
1893 | |||
1894 | |||
1895 | return; |
||
1896 | |||
1897 | |||
1898 | * arbitrary RGB values for background when we have transparency, and |
||
1899 | * so it is easy to determine the RGB values of the background color |
||
1900 | * from the info_ptr struct. |
||
1901 | */ |
||
1902 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
||
1903 | { |
||
1904 | background.index = buf[0]; |
||
1905 | |||
1906 | |||
1907 | { |
||
1908 | if (buf[0] >= info_ptr->num_palette) |
||
1909 | { |
||
1910 | png_chunk_benign_error(png_ptr, "invalid index"); |
||
1911 | return; |
||
1912 | } |
||
1913 | |||
1914 | |||
1915 | background.green = (png_uint_16)png_ptr->palette[buf[0]].green; |
||
1916 | background.blue = (png_uint_16)png_ptr->palette[buf[0]].blue; |
||
1917 | } |
||
1918 | |||
1919 | |||
1920 | background.red = background.green = background.blue = 0; |
||
1921 | |||
1922 | |||
1923 | } |
||
1924 | |||
1925 | |||
1926 | { |
||
1927 | background.index = 0; |
||
1928 | background.red = |
||
1929 | background.green = |
||
1930 | background.blue = |
||
1931 | background.gray = png_get_uint_16(buf); |
||
1932 | } |
||
1933 | |||
1934 | |||
1935 | { |
||
1936 | background.index = 0; |
||
1937 | background.red = png_get_uint_16(buf); |
||
1938 | background.green = png_get_uint_16(buf + 2); |
||
1939 | background.blue = png_get_uint_16(buf + 4); |
||
1940 | background.gray = 0; |
||
1941 | } |
||
1942 | |||
1943 | |||
1944 | } |
||
1945 | #endif |
||
1946 | |||
1947 | |||
1948 | void /* PRIVATE */ |
||
1949 | png_handle_hIST(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
1950 | { |
||
1951 | unsigned int num, i; |
||
1952 | png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH]; |
||
1953 | |||
1954 | |||
1955 | |||
1956 | |||
1957 | png_chunk_error(png_ptr, "missing IHDR"); |
||
1958 | |||
1959 | |||
1960 | { |
||
1961 | png_crc_finish(png_ptr, length); |
||
1962 | png_chunk_benign_error(png_ptr, "out of place"); |
||
1963 | return; |
||
1964 | } |
||
1965 | |||
1966 | |||
1967 | { |
||
1968 | png_crc_finish(png_ptr, length); |
||
1969 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
1970 | return; |
||
1971 | } |
||
1972 | |||
1973 | |||
1974 | |||
1975 | |||
1976 | { |
||
1977 | png_crc_finish(png_ptr, length); |
||
1978 | png_chunk_benign_error(png_ptr, "invalid"); |
||
1979 | return; |
||
1980 | } |
||
1981 | |||
1982 | |||
1983 | { |
||
1984 | png_byte buf[2]; |
||
1985 | |||
1986 | |||
1987 | readbuf[i] = png_get_uint_16(buf); |
||
1988 | } |
||
1989 | |||
1990 | |||
1991 | return; |
||
1992 | |||
1993 | |||
1994 | } |
||
1995 | #endif |
||
1996 | |||
1997 | |||
1998 | void /* PRIVATE */ |
||
1999 | png_handle_pHYs(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2000 | { |
||
2001 | png_byte buf[9]; |
||
2002 | png_uint_32 res_x, res_y; |
||
2003 | int unit_type; |
||
2004 | |||
2005 | |||
2006 | |||
2007 | |||
2008 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2009 | |||
2010 | |||
2011 | { |
||
2012 | png_crc_finish(png_ptr, length); |
||
2013 | png_chunk_benign_error(png_ptr, "out of place"); |
||
2014 | return; |
||
2015 | } |
||
2016 | |||
2017 | |||
2018 | { |
||
2019 | png_crc_finish(png_ptr, length); |
||
2020 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
2021 | return; |
||
2022 | } |
||
2023 | |||
2024 | |||
2025 | { |
||
2026 | png_crc_finish(png_ptr, length); |
||
2027 | png_chunk_benign_error(png_ptr, "invalid"); |
||
2028 | return; |
||
2029 | } |
||
2030 | |||
2031 | |||
2032 | |||
2033 | |||
2034 | return; |
||
2035 | |||
2036 | |||
2037 | res_y = png_get_uint_32(buf + 4); |
||
2038 | unit_type = buf[8]; |
||
2039 | png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type); |
||
2040 | } |
||
2041 | #endif |
||
2042 | |||
2043 | |||
2044 | void /* PRIVATE */ |
||
2045 | png_handle_oFFs(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2046 | { |
||
2047 | png_byte buf[9]; |
||
2048 | png_int_32 offset_x, offset_y; |
||
2049 | int unit_type; |
||
2050 | |||
2051 | |||
2052 | |||
2053 | |||
2054 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2055 | |||
2056 | |||
2057 | { |
||
2058 | png_crc_finish(png_ptr, length); |
||
2059 | png_chunk_benign_error(png_ptr, "out of place"); |
||
2060 | return; |
||
2061 | } |
||
2062 | |||
2063 | |||
2064 | { |
||
2065 | png_crc_finish(png_ptr, length); |
||
2066 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
2067 | return; |
||
2068 | } |
||
2069 | |||
2070 | |||
2071 | { |
||
2072 | png_crc_finish(png_ptr, length); |
||
2073 | png_chunk_benign_error(png_ptr, "invalid"); |
||
2074 | return; |
||
2075 | } |
||
2076 | |||
2077 | |||
2078 | |||
2079 | |||
2080 | return; |
||
2081 | |||
2082 | |||
2083 | offset_y = png_get_int_32(buf + 4); |
||
2084 | unit_type = buf[8]; |
||
2085 | png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type); |
||
2086 | } |
||
2087 | #endif |
||
2088 | |||
2089 | |||
2090 | /* Read the pCAL chunk (described in the PNG Extensions document) */ |
||
2091 | void /* PRIVATE */ |
||
2092 | png_handle_pCAL(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2093 | { |
||
2094 | png_int_32 X0, X1; |
||
2095 | png_byte type, nparams; |
||
2096 | png_bytep buffer, buf, units, endptr; |
||
2097 | png_charpp params; |
||
2098 | int i; |
||
2099 | |||
2100 | |||
2101 | |||
2102 | |||
2103 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2104 | |||
2105 | |||
2106 | { |
||
2107 | png_crc_finish(png_ptr, length); |
||
2108 | png_chunk_benign_error(png_ptr, "out of place"); |
||
2109 | return; |
||
2110 | } |
||
2111 | |||
2112 | |||
2113 | { |
||
2114 | png_crc_finish(png_ptr, length); |
||
2115 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
2116 | return; |
||
2117 | } |
||
2118 | |||
2119 | |||
2120 | length + 1); |
||
2121 | |||
2122 | |||
2123 | |||
2124 | |||
2125 | { |
||
2126 | png_crc_finish(png_ptr, length); |
||
2127 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
2128 | return; |
||
2129 | } |
||
2130 | |||
2131 | |||
2132 | |||
2133 | |||
2134 | return; |
||
2135 | |||
2136 | |||
2137 | |||
2138 | |||
2139 | for (buf = buffer; *buf; buf++) |
||
2140 | /* Empty loop */ ; |
||
2141 | |||
2142 | |||
2143 | |||
2144 | |||
2145 | * in order to get the parameter information. |
||
2146 | */ |
||
2147 | if (endptr <= buf + 12) |
||
2148 | { |
||
2149 | png_chunk_benign_error(png_ptr, "invalid"); |
||
2150 | return; |
||
2151 | } |
||
2152 | |||
2153 | |||
2154 | X0 = png_get_int_32((png_bytep)buf+1); |
||
2155 | X1 = png_get_int_32((png_bytep)buf+5); |
||
2156 | type = buf[9]; |
||
2157 | nparams = buf[10]; |
||
2158 | units = buf + 11; |
||
2159 | |||
2160 | |||
2161 | /* Check that we have the right number of parameters for known |
||
2162 | * equation types. |
||
2163 | */ |
||
2164 | if ((type == PNG_EQUATION_LINEAR && nparams != 2) || |
||
2165 | (type == PNG_EQUATION_BASE_E && nparams != 3) || |
||
2166 | (type == PNG_EQUATION_ARBITRARY && nparams != 3) || |
||
2167 | (type == PNG_EQUATION_HYPERBOLIC && nparams != 4)) |
||
2168 | { |
||
2169 | png_chunk_benign_error(png_ptr, "invalid parameter count"); |
||
2170 | return; |
||
2171 | } |
||
2172 | |||
2173 | |||
2174 | { |
||
2175 | png_chunk_benign_error(png_ptr, "unrecognized equation type"); |
||
2176 | } |
||
2177 | |||
2178 | |||
2179 | /* Empty loop to move past the units string. */ ; |
||
2180 | |||
2181 | |||
2182 | |||
2183 | |||
2184 | nparams * (sizeof (png_charp)))); |
||
2185 | |||
2186 | |||
2187 | { |
||
2188 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
2189 | return; |
||
2190 | } |
||
2191 | |||
2192 | |||
2193 | for (i = 0; i < nparams; i++) |
||
2194 | { |
||
2195 | buf++; /* Skip the null string terminator from previous parameter. */ |
||
2196 | |||
2197 | |||
2198 | |||
2199 | |||
2200 | /* Empty loop to move past each parameter string */ ; |
||
2201 | |||
2202 | |||
2203 | if (buf > endptr) |
||
2204 | { |
||
2205 | png_free(png_ptr, params); |
||
2206 | png_chunk_benign_error(png_ptr, "invalid data"); |
||
2207 | return; |
||
2208 | } |
||
2209 | } |
||
2210 | |||
2211 | |||
2212 | (png_charp)units, params); |
||
2213 | |||
2214 | |||
2215 | } |
||
2216 | #endif |
||
2217 | |||
2218 | |||
2219 | /* Read the sCAL chunk */ |
||
2220 | void /* PRIVATE */ |
||
2221 | png_handle_sCAL(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2222 | { |
||
2223 | png_bytep buffer; |
||
2224 | png_size_t i; |
||
2225 | int state; |
||
2226 | |||
2227 | |||
2228 | |||
2229 | |||
2230 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2231 | |||
2232 | |||
2233 | { |
||
2234 | png_crc_finish(png_ptr, length); |
||
2235 | png_chunk_benign_error(png_ptr, "out of place"); |
||
2236 | return; |
||
2237 | } |
||
2238 | |||
2239 | |||
2240 | { |
||
2241 | png_crc_finish(png_ptr, length); |
||
2242 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
2243 | return; |
||
2244 | } |
||
2245 | |||
2246 | |||
2247 | else if (length < 4) |
||
2248 | { |
||
2249 | png_crc_finish(png_ptr, length); |
||
2250 | png_chunk_benign_error(png_ptr, "invalid"); |
||
2251 | return; |
||
2252 | } |
||
2253 | |||
2254 | |||
2255 | length + 1); |
||
2256 | |||
2257 | |||
2258 | |||
2259 | |||
2260 | { |
||
2261 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
2262 | png_crc_finish(png_ptr, length); |
||
2263 | return; |
||
2264 | } |
||
2265 | |||
2266 | |||
2267 | buffer[length] = 0; /* Null terminate the last string */ |
||
2268 | |||
2269 | |||
2270 | return; |
||
2271 | |||
2272 | |||
2273 | if (buffer[0] != 1 && buffer[0] != 2) |
||
2274 | { |
||
2275 | png_chunk_benign_error(png_ptr, "invalid unit"); |
||
2276 | return; |
||
2277 | } |
||
2278 | |||
2279 | |||
2280 | * a '\0' and they need to fit exactly in the chunk data. |
||
2281 | */ |
||
2282 | i = 1; |
||
2283 | state = 0; |
||
2284 | |||
2285 | |||
2286 | i >= length || buffer[i++] != 0) |
||
2287 | png_chunk_benign_error(png_ptr, "bad width format"); |
||
2288 | |||
2289 | |||
2290 | png_chunk_benign_error(png_ptr, "non-positive width"); |
||
2291 | |||
2292 | |||
2293 | { |
||
2294 | png_size_t heighti = i; |
||
2295 | |||
2296 | |||
2297 | if (!png_check_fp_number((png_const_charp)buffer, length, &state, &i) || |
||
2298 | i != length) |
||
2299 | png_chunk_benign_error(png_ptr, "bad height format"); |
||
2300 | |||
2301 | |||
2302 | png_chunk_benign_error(png_ptr, "non-positive height"); |
||
2303 | |||
2304 | |||
2305 | /* This is the (only) success case. */ |
||
2306 | png_set_sCAL_s(png_ptr, info_ptr, buffer[0], |
||
2307 | (png_charp)buffer+1, (png_charp)buffer+heighti); |
||
2308 | } |
||
2309 | } |
||
2310 | #endif |
||
2311 | |||
2312 | |||
2313 | void /* PRIVATE */ |
||
2314 | png_handle_tIME(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2315 | { |
||
2316 | png_byte buf[7]; |
||
2317 | png_time mod_time; |
||
2318 | |||
2319 | |||
2320 | |||
2321 | |||
2322 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2323 | |||
2324 | |||
2325 | { |
||
2326 | png_crc_finish(png_ptr, length); |
||
2327 | png_chunk_benign_error(png_ptr, "duplicate"); |
||
2328 | return; |
||
2329 | } |
||
2330 | |||
2331 | |||
2332 | png_ptr->mode |= PNG_AFTER_IDAT; |
||
2333 | |||
2334 | |||
2335 | { |
||
2336 | png_crc_finish(png_ptr, length); |
||
2337 | png_chunk_benign_error(png_ptr, "invalid"); |
||
2338 | return; |
||
2339 | } |
||
2340 | |||
2341 | |||
2342 | |||
2343 | |||
2344 | return; |
||
2345 | |||
2346 | |||
2347 | mod_time.minute = buf[5]; |
||
2348 | mod_time.hour = buf[4]; |
||
2349 | mod_time.day = buf[3]; |
||
2350 | mod_time.month = buf[2]; |
||
2351 | mod_time.year = png_get_uint_16(buf); |
||
2352 | |||
2353 | |||
2354 | } |
||
2355 | #endif |
||
2356 | |||
2357 | |||
2358 | /* Note: this does not properly handle chunks that are > 64K under DOS */ |
||
2359 | void /* PRIVATE */ |
||
2360 | png_handle_tEXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2361 | { |
||
2362 | png_text text_info; |
||
2363 | png_bytep buffer; |
||
2364 | png_charp key; |
||
2365 | png_charp text; |
||
2366 | png_uint_32 skip = 0; |
||
2367 | |||
2368 | |||
2369 | |||
2370 | |||
2371 | if (png_ptr->user_chunk_cache_max != 0) |
||
2372 | { |
||
2373 | if (png_ptr->user_chunk_cache_max == 1) |
||
2374 | { |
||
2375 | png_crc_finish(png_ptr, length); |
||
2376 | return; |
||
2377 | } |
||
2378 | |||
2379 | |||
2380 | { |
||
2381 | png_crc_finish(png_ptr, length); |
||
2382 | png_chunk_benign_error(png_ptr, "no space in chunk cache"); |
||
2383 | return; |
||
2384 | } |
||
2385 | } |
||
2386 | #endif |
||
2387 | |||
2388 | |||
2389 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2390 | |||
2391 | |||
2392 | png_ptr->mode |= PNG_AFTER_IDAT; |
||
2393 | |||
2394 | |||
2395 | if (length > 65535U) |
||
2396 | { |
||
2397 | png_crc_finish(png_ptr, length); |
||
2398 | png_chunk_benign_error(png_ptr, "too large to fit in memory"); |
||
2399 | return; |
||
2400 | } |
||
2401 | #endif |
||
2402 | |||
2403 | |||
2404 | |||
2405 | |||
2406 | { |
||
2407 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
2408 | return; |
||
2409 | } |
||
2410 | |||
2411 | |||
2412 | |||
2413 | |||
2414 | return; |
||
2415 | |||
2416 | |||
2417 | key[length] = 0; |
||
2418 | |||
2419 | |||
2420 | /* Empty loop to find end of key */ ; |
||
2421 | |||
2422 | |||
2423 | text++; |
||
2424 | |||
2425 | |||
2426 | text_info.key = key; |
||
2427 | text_info.lang = NULL; |
||
2428 | text_info.lang_key = NULL; |
||
2429 | text_info.itxt_length = 0; |
||
2430 | text_info.text = text; |
||
2431 | text_info.text_length = strlen(text); |
||
2432 | |||
2433 | |||
2434 | png_warning(png_ptr, "Insufficient memory to process text chunk"); |
||
2435 | } |
||
2436 | #endif |
||
2437 | |||
2438 | |||
2439 | /* Note: this does not correctly handle chunks that are > 64K under DOS */ |
||
2440 | void /* PRIVATE */ |
||
2441 | png_handle_zTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2442 | { |
||
2443 | png_const_charp errmsg = NULL; |
||
2444 | png_bytep buffer; |
||
2445 | png_uint_32 keyword_length; |
||
2446 | |||
2447 | |||
2448 | |||
2449 | |||
2450 | if (png_ptr->user_chunk_cache_max != 0) |
||
2451 | { |
||
2452 | if (png_ptr->user_chunk_cache_max == 1) |
||
2453 | { |
||
2454 | png_crc_finish(png_ptr, length); |
||
2455 | return; |
||
2456 | } |
||
2457 | |||
2458 | |||
2459 | { |
||
2460 | png_crc_finish(png_ptr, length); |
||
2461 | png_chunk_benign_error(png_ptr, "no space in chunk cache"); |
||
2462 | return; |
||
2463 | } |
||
2464 | } |
||
2465 | #endif |
||
2466 | |||
2467 | |||
2468 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2469 | |||
2470 | |||
2471 | png_ptr->mode |= PNG_AFTER_IDAT; |
||
2472 | |||
2473 | |||
2474 | |||
2475 | |||
2476 | { |
||
2477 | png_crc_finish(png_ptr, length); |
||
2478 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
2479 | return; |
||
2480 | } |
||
2481 | |||
2482 | |||
2483 | |||
2484 | |||
2485 | return; |
||
2486 | |||
2487 | |||
2488 | for (keyword_length = 0; |
||
2489 | keyword_length < length && buffer[keyword_length] != 0; |
||
2490 | ++keyword_length) |
||
2491 | /* Empty loop to find end of name */ ; |
||
2492 | |||
2493 | |||
2494 | errmsg = "bad keyword"; |
||
2495 | |||
2496 | |||
2497 | * zero bytes; we need a '\0' at the end of the keyword, the compression type |
||
2498 | * then the LZ data: |
||
2499 | */ |
||
2500 | else if (keyword_length + 3 > length) |
||
2501 | errmsg = "truncated"; |
||
2502 | |||
2503 | |||
2504 | errmsg = "unknown compression type"; |
||
2505 | |||
2506 | |||
2507 | { |
||
2508 | png_alloc_size_t uncompressed_length = PNG_SIZE_MAX; |
||
2509 | |||
2510 | |||
2511 | * level memory limit, this should be split to different values for iCCP |
||
2512 | * and text chunks. |
||
2513 | */ |
||
2514 | if (png_decompress_chunk(png_ptr, length, keyword_length+2, |
||
2515 | &uncompressed_length, 1/*terminate*/) == Z_STREAM_END) |
||
2516 | { |
||
2517 | png_text text; |
||
2518 | |||
2519 | |||
2520 | * for the extra compression type byte and the fact that it isn't |
||
2521 | * necessarily '\0' terminated. |
||
2522 | */ |
||
2523 | buffer = png_ptr->read_buffer; |
||
2524 | buffer[uncompressed_length+(keyword_length+2)] = 0; |
||
2525 | |||
2526 | |||
2527 | text.key = (png_charp)buffer; |
||
2528 | text.text = (png_charp)(buffer + keyword_length+2); |
||
2529 | text.text_length = uncompressed_length; |
||
2530 | text.itxt_length = 0; |
||
2531 | text.lang = NULL; |
||
2532 | text.lang_key = NULL; |
||
2533 | |||
2534 | |||
2535 | errmsg = "insufficient memory"; |
||
2536 | } |
||
2537 | |||
2538 | |||
2539 | errmsg = png_ptr->zstream.msg; |
||
2540 | } |
||
2541 | |||
2542 | |||
2543 | png_chunk_benign_error(png_ptr, errmsg); |
||
2544 | } |
||
2545 | #endif |
||
2546 | |||
2547 | |||
2548 | /* Note: this does not correctly handle chunks that are > 64K under DOS */ |
||
2549 | void /* PRIVATE */ |
||
2550 | png_handle_iTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length) |
||
2551 | { |
||
2552 | png_const_charp errmsg = NULL; |
||
2553 | png_bytep buffer; |
||
2554 | png_uint_32 prefix_length; |
||
2555 | |||
2556 | |||
2557 | |||
2558 | |||
2559 | if (png_ptr->user_chunk_cache_max != 0) |
||
2560 | { |
||
2561 | if (png_ptr->user_chunk_cache_max == 1) |
||
2562 | { |
||
2563 | png_crc_finish(png_ptr, length); |
||
2564 | return; |
||
2565 | } |
||
2566 | |||
2567 | |||
2568 | { |
||
2569 | png_crc_finish(png_ptr, length); |
||
2570 | png_chunk_benign_error(png_ptr, "no space in chunk cache"); |
||
2571 | return; |
||
2572 | } |
||
2573 | } |
||
2574 | #endif |
||
2575 | |||
2576 | |||
2577 | png_chunk_error(png_ptr, "missing IHDR"); |
||
2578 | |||
2579 | |||
2580 | png_ptr->mode |= PNG_AFTER_IDAT; |
||
2581 | |||
2582 | |||
2583 | |||
2584 | |||
2585 | { |
||
2586 | png_crc_finish(png_ptr, length); |
||
2587 | png_chunk_benign_error(png_ptr, "out of memory"); |
||
2588 | return; |
||
2589 | } |
||
2590 | |||
2591 | |||
2592 | |||
2593 | |||
2594 | return; |
||
2595 | |||
2596 | |||
2597 | for (prefix_length=0; |
||
2598 | prefix_length < length && buffer[prefix_length] != 0; |
||
2599 | ++prefix_length) |
||
2600 | /* Empty loop */ ; |
||
2601 | |||
2602 | |||
2603 | if (prefix_length > 79 || prefix_length < 1) |
||
2604 | errmsg = "bad keyword"; |
||
2605 | |||
2606 | |||
2607 | * keyword (both may be empty but are 0 terminated) then the text, which may |
||
2608 | * be empty. |
||
2609 | */ |
||
2610 | else if (prefix_length + 5 > length) |
||
2611 | errmsg = "truncated"; |
||
2612 | |||
2613 | |||
2614 | (buffer[prefix_length+1] == 1 && |
||
2615 | buffer[prefix_length+2] == PNG_COMPRESSION_TYPE_BASE)) |
||
2616 | { |
||
2617 | int compressed = buffer[prefix_length+1] != 0; |
||
2618 | png_uint_32 language_offset, translated_keyword_offset; |
||
2619 | png_alloc_size_t uncompressed_length = 0; |
||
2620 | |||
2621 | |||
2622 | prefix_length += 3; |
||
2623 | language_offset = prefix_length; |
||
2624 | |||
2625 | |||
2626 | ++prefix_length) |
||
2627 | /* Empty loop */ ; |
||
2628 | |||
2629 | |||
2630 | translated_keyword_offset = ++prefix_length; |
||
2631 | |||
2632 | |||
2633 | ++prefix_length) |
||
2634 | /* Empty loop */ ; |
||
2635 | |||
2636 | |||
2637 | * keyword, but it may already be over the end. None of this arithmetic |
||
2638 | * can overflow because chunks are at most 2^31 bytes long, but on 16-bit |
||
2639 | * systems the available allocaton may overflow. |
||
2640 | */ |
||
2641 | ++prefix_length; |
||
2642 | |||
2643 | |||
2644 | uncompressed_length = length - prefix_length; |
||
2645 | |||
2646 | |||
2647 | { |
||
2648 | uncompressed_length = PNG_SIZE_MAX; |
||
2649 | |||
2650 | |||
2651 | * level memory limit, this should be split to different values for |
||
2652 | * iCCP and text chunks. |
||
2653 | */ |
||
2654 | if (png_decompress_chunk(png_ptr, length, prefix_length, |
||
2655 | &uncompressed_length, 1/*terminate*/) == Z_STREAM_END) |
||
2656 | buffer = png_ptr->read_buffer; |
||
2657 | |||
2658 | |||
2659 | errmsg = png_ptr->zstream.msg; |
||
2660 | } |
||
2661 | |||
2662 | |||
2663 | errmsg = "truncated"; |
||
2664 | |||
2665 | |||
2666 | { |
||
2667 | png_text text; |
||
2668 | |||
2669 | |||
2670 | |||
2671 | |||
2672 | text.compression = PNG_ITXT_COMPRESSION_NONE; |
||
2673 | |||
2674 | |||
2675 | text.compression = PNG_ITXT_COMPRESSION_zTXt; |
||
2676 | |||
2677 | |||
2678 | text.lang = (png_charp)buffer + language_offset; |
||
2679 | text.lang_key = (png_charp)buffer + translated_keyword_offset; |
||
2680 | text.text = (png_charp)buffer + prefix_length; |
||
2681 | text.text_length = 0; |
||
2682 | text.itxt_length = uncompressed_length; |
||
2683 | |||
2684 | |||
2685 | errmsg = "insufficient memory"; |
||
2686 | } |
||
2687 | } |
||
2688 | |||
2689 | |||
2690 | errmsg = "bad compression info"; |
||
2691 | |||
2692 | |||
2693 | png_chunk_benign_error(png_ptr, errmsg); |
||
2694 | } |
||
2695 | #endif |
||
2696 | |||
2697 | |||
2698 | /* Utility function for png_handle_unknown; set up png_ptr::unknown_chunk */ |
||
2699 | static int |
||
2700 | png_cache_unknown_chunk(png_structrp png_ptr, png_uint_32 length) |
||
2701 | { |
||
2702 | png_alloc_size_t limit = PNG_SIZE_MAX; |
||
2703 | |||
2704 | |||
2705 | { |
||
2706 | png_free(png_ptr, png_ptr->unknown_chunk.data); |
||
2707 | png_ptr->unknown_chunk.data = NULL; |
||
2708 | } |
||
2709 | |||
2710 | |||
2711 | if (png_ptr->user_chunk_malloc_max > 0 && |
||
2712 | png_ptr->user_chunk_malloc_max < limit) |
||
2713 | limit = png_ptr->user_chunk_malloc_max; |
||
2714 | |||
2715 | |||
2716 | if (PNG_USER_CHUNK_MALLOC_MAX < limit) |
||
2717 | limit = PNG_USER_CHUNK_MALLOC_MAX; |
||
2718 | # endif |
||
2719 | |||
2720 | |||
2721 | { |
||
2722 | PNG_CSTRING_FROM_CHUNK(png_ptr->unknown_chunk.name, png_ptr->chunk_name); |
||
2723 | /* The following is safe because of the PNG_SIZE_MAX init above */ |
||
2724 | png_ptr->unknown_chunk.size = (png_size_t)length/*SAFE*/; |
||
2725 | /* 'mode' is a flag array, only the bottom four bits matter here */ |
||
2726 | png_ptr->unknown_chunk.location = (png_byte)png_ptr->mode/*SAFE*/; |
||
2727 | |||
2728 | |||
2729 | png_ptr->unknown_chunk.data = NULL; |
||
2730 | |||
2731 | |||
2732 | { |
||
2733 | /* Do a 'warn' here - it is handled below. */ |
||
2734 | png_ptr->unknown_chunk.data = png_voidcast(png_bytep, |
||
2735 | png_malloc_warn(png_ptr, length)); |
||
2736 | } |
||
2737 | } |
||
2738 | |||
2739 | |||
2740 | { |
||
2741 | /* This is benign because we clean up correctly */ |
||
2742 | png_crc_finish(png_ptr, length); |
||
2743 | png_chunk_benign_error(png_ptr, "unknown chunk exceeds memory limits"); |
||
2744 | return 0; |
||
2745 | } |
||
2746 | |||
2747 | |||
2748 | { |
||
2749 | if (length > 0) |
||
2750 | png_crc_read(png_ptr, png_ptr->unknown_chunk.data, length); |
||
2751 | png_crc_finish(png_ptr, 0); |
||
2752 | return 1; |
||
2753 | } |
||
2754 | } |
||
2755 | #endif /* PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */ |
||
2756 | |||
2757 | |||
2758 | void /* PRIVATE */ |
||
2759 | png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr, |
||
2760 | png_uint_32 length, int keep) |
||
2761 | { |
||
2762 | int handled = 0; /* the chunk was handled */ |
||
2763 | |||
2764 | |||
2765 | |||
2766 | |||
2767 | * the bug which meant that setting a non-default behavior for a specific |
||
2768 | * chunk would be ignored (the default was always used unless a user |
||
2769 | * callback was installed). |
||
2770 | * |
||
2771 | * 'keep' is the value from the png_chunk_unknown_handling, the setting for |
||
2772 | * this specific chunk_name, if PNG_HANDLE_AS_UNKNOWN_SUPPORTED, if not it |
||
2773 | * will always be PNG_HANDLE_CHUNK_AS_DEFAULT and it needs to be set here. |
||
2774 | * This is just an optimization to avoid multiple calls to the lookup |
||
2775 | * function. |
||
2776 | */ |
||
2777 | # ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
||
2778 | keep = png_chunk_unknown_handling(png_ptr, png_ptr->chunk_name); |
||
2779 | # endif |
||
2780 | |||
2781 | |||
2782 | * of these is always defined because this is the only way to switch on |
||
2783 | * PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) |
||
2784 | */ |
||
2785 | #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED |
||
2786 | # ifdef PNG_READ_USER_CHUNKS_SUPPORTED |
||
2787 | /* The user callback takes precedence over the chunk keep value, but the |
||
2788 | * keep value is still required to validate a save of a critical chunk. |
||
2789 | */ |
||
2790 | if (png_ptr->read_user_chunk_fn != NULL) |
||
2791 | { |
||
2792 | if (png_cache_unknown_chunk(png_ptr, length)) |
||
2793 | { |
||
2794 | /* Callback to user unknown chunk handler */ |
||
2795 | int ret = (*(png_ptr->read_user_chunk_fn))(png_ptr, |
||
2796 | &png_ptr->unknown_chunk); |
||
2797 | |||
2798 | |||
2799 | * negative: An error occured, png_chunk_error will be called. |
||
2800 | * zero: The chunk was not handled, the chunk will be discarded |
||
2801 | * unless png_set_keep_unknown_chunks has been used to set |
||
2802 | * a 'keep' behavior for this particular chunk, in which |
||
2803 | * case that will be used. A critical chunk will cause an |
||
2804 | * error at this point unless it is to be saved. |
||
2805 | * positive: The chunk was handled, libpng will ignore/discard it. |
||
2806 | */ |
||
2807 | if (ret < 0) |
||
2808 | png_chunk_error(png_ptr, "error in user chunk"); |
||
2809 | |||
2810 | |||
2811 | { |
||
2812 | /* If the keep value is 'default' or 'never' override it, but |
||
2813 | * still error out on critical chunks unless the keep value is |
||
2814 | * 'always' While this is weird it is the behavior in 1.4.12. |
||
2815 | * A possible improvement would be to obey the value set for the |
||
2816 | * chunk, but this would be an API change that would probably |
||
2817 | * damage some applications. |
||
2818 | * |
||
2819 | * The png_app_warning below catches the case that matters, where |
||
2820 | * the application has not set specific save or ignore for this |
||
2821 | * chunk or global save or ignore. |
||
2822 | */ |
||
2823 | if (keep < PNG_HANDLE_CHUNK_IF_SAFE) |
||
2824 | { |
||
2825 | # ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED |
||
2826 | if (png_ptr->unknown_default < PNG_HANDLE_CHUNK_IF_SAFE) |
||
2827 | { |
||
2828 | png_chunk_warning(png_ptr, "Saving unknown chunk:"); |
||
2829 | png_app_warning(png_ptr, |
||
2830 | "forcing save of an unhandled chunk;" |
||
2831 | " please call png_set_keep_unknown_chunks"); |
||
2832 | /* with keep = PNG_HANDLE_CHUNK_IF_SAFE */ |
||
2833 | } |
||
2834 | # endif |
||
2835 | keep = PNG_HANDLE_CHUNK_IF_SAFE; |
||
2836 | } |
||
2837 | } |
||
2838 | |||
2839 | |||
2840 | { |
||
2841 | handled = 1; |
||
2842 | /* Critical chunks can be safely discarded at this point. */ |
||
2843 | keep = PNG_HANDLE_CHUNK_NEVER; |
||
2844 | } |
||
2845 | } |
||
2846 | |||
2847 | |||
2848 | keep = PNG_HANDLE_CHUNK_NEVER; /* insufficient memory */ |
||
2849 | } |
||
2850 | |||
2851 | |||
2852 | /* Use the SAVE_UNKNOWN_CHUNKS code or skip the chunk */ |
||
2853 | # endif /* PNG_READ_USER_CHUNKS_SUPPORTED */ |
||
2854 | |||
2855 | |||
2856 | { |
||
2857 | /* keep is currently just the per-chunk setting, if there was no |
||
2858 | * setting change it to the global default now (not that this may |
||
2859 | * still be AS_DEFAULT) then obtain the cache of the chunk if required, |
||
2860 | * if not simply skip the chunk. |
||
2861 | */ |
||
2862 | if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT) |
||
2863 | keep = png_ptr->unknown_default; |
||
2864 | |||
2865 | |||
2866 | (keep == PNG_HANDLE_CHUNK_IF_SAFE && |
||
2867 | PNG_CHUNK_ANCILLARY(png_ptr->chunk_name))) |
||
2868 | { |
||
2869 | if (!png_cache_unknown_chunk(png_ptr, length)) |
||
2870 | keep = PNG_HANDLE_CHUNK_NEVER; |
||
2871 | } |
||
2872 | |||
2873 | |||
2874 | png_crc_finish(png_ptr, length); |
||
2875 | } |
||
2876 | # else |
||
2877 | # ifndef PNG_READ_USER_CHUNKS_SUPPORTED |
||
2878 | # error no method to support READ_UNKNOWN_CHUNKS |
||
2879 | # endif |
||
2880 | |||
2881 | |||
2882 | /* If here there is no read callback pointer set and no support is |
||
2883 | * compiled in to just save the unknown chunks, so simply skip this |
||
2884 | * chunk. If 'keep' is something other than AS_DEFAULT or NEVER then |
||
2885 | * the app has erroneously asked for unknown chunk saving when there |
||
2886 | * is no support. |
||
2887 | */ |
||
2888 | if (keep > PNG_HANDLE_CHUNK_NEVER) |
||
2889 | png_app_error(png_ptr, "no unknown chunk support available"); |
||
2890 | |||
2891 | |||
2892 | } |
||
2893 | # endif /* PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED */ |
||
2894 | |||
2895 | |||
2896 | /* Now store the chunk in the chunk list if appropriate, and if the limits |
||
2897 | * permit it. |
||
2898 | */ |
||
2899 | if (keep == PNG_HANDLE_CHUNK_ALWAYS || |
||
2900 | (keep == PNG_HANDLE_CHUNK_IF_SAFE && |
||
2901 | PNG_CHUNK_ANCILLARY(png_ptr->chunk_name))) |
||
2902 | { |
||
2903 | # ifdef PNG_USER_LIMITS_SUPPORTED |
||
2904 | switch (png_ptr->user_chunk_cache_max) |
||
2905 | { |
||
2906 | case 2: |
||
2907 | png_ptr->user_chunk_cache_max = 1; |
||
2908 | png_chunk_benign_error(png_ptr, "no space in chunk cache"); |
||
2909 | /* FALL THROUGH */ |
||
2910 | case 1: |
||
2911 | /* NOTE: prior to 1.6.0 this case resulted in an unknown critical |
||
2912 | * chunk being skipped, now there will be a hard error below. |
||
2913 | */ |
||
2914 | break; |
||
2915 | |||
2916 | |||
2917 | --(png_ptr->user_chunk_cache_max); |
||
2918 | /* FALL THROUGH */ |
||
2919 | case 0: /* no limit */ |
||
2920 | # endif /* PNG_USER_LIMITS_SUPPORTED */ |
||
2921 | /* Here when the limit isn't reached or when limits are compiled |
||
2922 | * out; store the chunk. |
||
2923 | */ |
||
2924 | png_set_unknown_chunks(png_ptr, info_ptr, |
||
2925 | &png_ptr->unknown_chunk, 1); |
||
2926 | handled = 1; |
||
2927 | # ifdef PNG_USER_LIMITS_SUPPORTED |
||
2928 | break; |
||
2929 | } |
||
2930 | # endif |
||
2931 | } |
||
2932 | # else /* no store support! */ |
||
2933 | PNG_UNUSED(info_ptr) |
||
2934 | # error untested code (reading unknown chunks with no store support) |
||
2935 | # endif |
||
2936 | |||
2937 | |||
2938 | * freed now. Notice that the data is not freed if there is a png_error, but |
||
2939 | * it will be freed by destroy_read_struct. |
||
2940 | */ |
||
2941 | if (png_ptr->unknown_chunk.data != NULL) |
||
2942 | png_free(png_ptr, png_ptr->unknown_chunk.data); |
||
2943 | png_ptr->unknown_chunk.data = NULL; |
||
2944 | |||
2945 | |||
2946 | /* There is no support to read an unknown chunk, so just skip it. */ |
||
2947 | png_crc_finish(png_ptr, length); |
||
2948 | PNG_UNUSED(info_ptr) |
||
2949 | PNG_UNUSED(keep) |
||
2950 | #endif /* !PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */ |
||
2951 | |||
2952 | |||
2953 | if (!handled && PNG_CHUNK_CRITICAL(png_ptr->chunk_name)) |
||
2954 | png_chunk_error(png_ptr, "unhandled critical chunk"); |
||
2955 | } |
||
2956 | |||
2957 | |||
2958 | * This function can't have the "critical chunk check" incorporated |
||
2959 | * into it, since in the future we will need to be able to call user |
||
2960 | * functions to handle unknown critical chunks after we check that |
||
2961 | * the chunk name itself is valid. |
||
2962 | */ |
||
2963 | |||
2964 | |||
2965 | * |
||
2966 | * ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) |
||
2967 | */ |
||
2968 | |||
2969 | |||
2970 | png_check_chunk_name(png_structrp png_ptr, png_uint_32 chunk_name) |
||
2971 | { |
||
2972 | int i; |
||
2973 | |||
2974 | |||
2975 | |||
2976 | |||
2977 | { |
||
2978 | int c = chunk_name & 0xff; |
||
2979 | |||
2980 | |||
2981 | png_chunk_error(png_ptr, "invalid chunk type"); |
||
2982 | |||
2983 | |||
2984 | } |
||
2985 | } |
||
2986 | |||
2987 | |||
2988 | * routine takes care of alpha and transparency if requested. This routine also |
||
2989 | * handles the two methods of progressive display of interlaced images, |
||
2990 | * depending on the 'display' value; if 'display' is true then the whole row |
||
2991 | * (dp) is filled from the start by replicating the available pixels. If |
||
2992 | * 'display' is false only those pixels present in the pass are filled in. |
||
2993 | */ |
||
2994 | void /* PRIVATE */ |
||
2995 | png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display) |
||
2996 | { |
||
2997 | unsigned int pixel_depth = png_ptr->transformed_pixel_depth; |
||
2998 | png_const_bytep sp = png_ptr->row_buf + 1; |
||
2999 | png_uint_32 row_width = png_ptr->width; |
||
3000 | unsigned int pass = png_ptr->pass; |
||
3001 | png_bytep end_ptr = 0; |
||
3002 | png_byte end_byte = 0; |
||
3003 | unsigned int end_mask; |
||
3004 | |||
3005 | |||
3006 | |||
3007 | |||
3008 | * least one row has been read from the PNG data and transformed. |
||
3009 | */ |
||
3010 | if (pixel_depth == 0) |
||
3011 | png_error(png_ptr, "internal row logic error"); |
||
3012 | |||
3013 | |||
3014 | * any call to png_read_update_info at this point. Do not continue if we got |
||
3015 | * this wrong. |
||
3016 | */ |
||
3017 | if (png_ptr->info_rowbytes != 0 && png_ptr->info_rowbytes != |
||
3018 | PNG_ROWBYTES(pixel_depth, row_width)) |
||
3019 | png_error(png_ptr, "internal row size calculation error"); |
||
3020 | |||
3021 | |||
3022 | if (row_width == 0) |
||
3023 | png_error(png_ptr, "internal row width error"); |
||
3024 | |||
3025 | |||
3026 | * the multiply below may overflow, we don't care because ANSI-C guarantees |
||
3027 | * we get the low bits. |
||
3028 | */ |
||
3029 | end_mask = (pixel_depth * row_width) & 7; |
||
3030 | if (end_mask != 0) |
||
3031 | { |
||
3032 | /* end_ptr == NULL is a flag to say do nothing */ |
||
3033 | end_ptr = dp + PNG_ROWBYTES(pixel_depth, row_width) - 1; |
||
3034 | end_byte = *end_ptr; |
||
3035 | # ifdef PNG_READ_PACKSWAP_SUPPORTED |
||
3036 | if (png_ptr->transformations & PNG_PACKSWAP) /* little-endian byte */ |
||
3037 | end_mask = 0xff << end_mask; |
||
3038 | |||
3039 | |||
3040 | # endif |
||
3041 | end_mask = 0xff >> end_mask; |
||
3042 | /* end_mask is now the bits to *keep* from the destination row */ |
||
3043 | } |
||
3044 | |||
3045 | |||
3046 | * will also happen if interlacing isn't supported or if the application |
||
3047 | * does not call png_set_interlace_handling(). In the latter cases the |
||
3048 | * caller just gets a sequence of the unexpanded rows from each interlace |
||
3049 | * pass. |
||
3050 | */ |
||
3051 | #ifdef PNG_READ_INTERLACING_SUPPORTED |
||
3052 | if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE) && |
||
3053 | pass < 6 && (display == 0 || |
||
3054 | /* The following copies everything for 'display' on passes 0, 2 and 4. */ |
||
3055 | (display == 1 && (pass & 1) != 0))) |
||
3056 | { |
||
3057 | /* Narrow images may have no bits in a pass; the caller should handle |
||
3058 | * this, but this test is cheap: |
||
3059 | */ |
||
3060 | if (row_width <= PNG_PASS_START_COL(pass)) |
||
3061 | return; |
||
3062 | |||
3063 | |||
3064 | { |
||
3065 | /* For pixel depths up to 4 bpp the 8-pixel mask can be expanded to fit |
||
3066 | * into 32 bits, then a single loop over the bytes using the four byte |
||
3067 | * values in the 32-bit mask can be used. For the 'display' option the |
||
3068 | * expanded mask may also not require any masking within a byte. To |
||
3069 | * make this work the PACKSWAP option must be taken into account - it |
||
3070 | * simply requires the pixels to be reversed in each byte. |
||
3071 | * |
||
3072 | * The 'regular' case requires a mask for each of the first 6 passes, |
||
3073 | * the 'display' case does a copy for the even passes in the range |
||
3074 | * 0..6. This has already been handled in the test above. |
||
3075 | * |
||
3076 | * The masks are arranged as four bytes with the first byte to use in |
||
3077 | * the lowest bits (little-endian) regardless of the order (PACKSWAP or |
||
3078 | * not) of the pixels in each byte. |
||
3079 | * |
||
3080 | * NOTE: the whole of this logic depends on the caller of this function |
||
3081 | * only calling it on rows appropriate to the pass. This function only |
||
3082 | * understands the 'x' logic; the 'y' logic is handled by the caller. |
||
3083 | * |
||
3084 | * The following defines allow generation of compile time constant bit |
||
3085 | * masks for each pixel depth and each possibility of swapped or not |
||
3086 | * swapped bytes. Pass 'p' is in the range 0..6; 'x', a pixel index, |
||
3087 | * is in the range 0..7; and the result is 1 if the pixel is to be |
||
3088 | * copied in the pass, 0 if not. 'S' is for the sparkle method, 'B' |
||
3089 | * for the block method. |
||
3090 | * |
||
3091 | * With some compilers a compile time expression of the general form: |
||
3092 | * |
||
3093 | * (shift >= 32) ? (a >> (shift-32)) : (b >> shift) |
||
3094 | * |
||
3095 | * Produces warnings with values of 'shift' in the range 33 to 63 |
||
3096 | * because the right hand side of the ?: expression is evaluated by |
||
3097 | * the compiler even though it isn't used. Microsoft Visual C (various |
||
3098 | * versions) and the Intel C compiler are known to do this. To avoid |
||
3099 | * this the following macros are used in 1.5.6. This is a temporary |
||
3100 | * solution to avoid destabilizing the code during the release process. |
||
3101 | */ |
||
3102 | # if PNG_USE_COMPILE_TIME_MASKS |
||
3103 | # define PNG_LSR(x,s) ((x)>>((s) & 0x1f)) |
||
3104 | # define PNG_LSL(x,s) ((x)<<((s) & 0x1f)) |
||
3105 | # else |
||
3106 | # define PNG_LSR(x,s) ((x)>>(s)) |
||
3107 | # define PNG_LSL(x,s) ((x)<<(s)) |
||
3108 | # endif |
||
3109 | # define S_COPY(p,x) (((p)<4 ? PNG_LSR(0x80088822,(3-(p))*8+(7-(x))) :\ |
||
3110 | PNG_LSR(0xaa55ff00,(7-(p))*8+(7-(x)))) & 1) |
||
3111 | # define B_COPY(p,x) (((p)<4 ? PNG_LSR(0xff0fff33,(3-(p))*8+(7-(x))) :\ |
||
3112 | PNG_LSR(0xff55ff00,(7-(p))*8+(7-(x)))) & 1) |
||
3113 | |||
3114 | |||
3115 | * little endian - the first pixel is at bit 0 - however the extra |
||
3116 | * parameter 's' can be set to cause the mask position to be swapped |
||
3117 | * within each byte, to match the PNG format. This is done by XOR of |
||
3118 | * the shift with 7, 6 or 4 for bit depths 1, 2 and 4. |
||
3119 | */ |
||
3120 | # define PIXEL_MASK(p,x,d,s) \ |
||
3121 | (PNG_LSL(((PNG_LSL(1U,(d)))-1),(((x)*(d))^((s)?8-(d):0)))) |
||
3122 | |||
3123 | |||
3124 | */ |
||
3125 | # define S_MASKx(p,x,d,s) (S_COPY(p,x)?PIXEL_MASK(p,x,d,s):0) |
||
3126 | # define B_MASKx(p,x,d,s) (B_COPY(p,x)?PIXEL_MASK(p,x,d,s):0) |
||
3127 | |||
3128 | |||
3129 | * cases the result needs replicating, for the 4-bpp case the above |
||
3130 | * generates a full 32 bits. |
||
3131 | */ |
||
3132 | # define MASK_EXPAND(m,d) ((m)*((d)==1?0x01010101:((d)==2?0x00010001:1))) |
||
3133 | |||
3134 | |||
3135 | S_MASKx(p,2,d,s) + S_MASKx(p,3,d,s) + S_MASKx(p,4,d,s) +\ |
||
3136 | S_MASKx(p,5,d,s) + S_MASKx(p,6,d,s) + S_MASKx(p,7,d,s), d) |
||
3137 | |||
3138 | |||
3139 | B_MASKx(p,2,d,s) + B_MASKx(p,3,d,s) + B_MASKx(p,4,d,s) +\ |
||
3140 | B_MASKx(p,5,d,s) + B_MASKx(p,6,d,s) + B_MASKx(p,7,d,s), d) |
||
3141 | |||
3142 | |||
3143 | /* Utility macros to construct all the masks for a depth/swap |
||
3144 | * combination. The 's' parameter says whether the format is PNG |
||
3145 | * (big endian bytes) or not. Only the three odd-numbered passes are |
||
3146 | * required for the display/block algorithm. |
||
3147 | */ |
||
3148 | # define S_MASKS(d,s) { S_MASK(0,d,s), S_MASK(1,d,s), S_MASK(2,d,s),\ |
||
3149 | S_MASK(3,d,s), S_MASK(4,d,s), S_MASK(5,d,s) } |
||
3150 | |||
3151 | |||
3152 | |||
3153 | |||
3154 | |||
3155 | |||
3156 | * then pass: |
||
3157 | */ |
||
3158 | static PNG_CONST png_uint_32 row_mask[2/*PACKSWAP*/][3/*depth*/][6] = |
||
3159 | { |
||
3160 | /* Little-endian byte masks for PACKSWAP */ |
||
3161 | { S_MASKS(1,0), S_MASKS(2,0), S_MASKS(4,0) }, |
||
3162 | /* Normal (big-endian byte) masks - PNG format */ |
||
3163 | { S_MASKS(1,1), S_MASKS(2,1), S_MASKS(4,1) } |
||
3164 | }; |
||
3165 | |||
3166 | |||
3167 | * pass>>1. |
||
3168 | */ |
||
3169 | static PNG_CONST png_uint_32 display_mask[2][3][3] = |
||
3170 | { |
||
3171 | /* Little-endian byte masks for PACKSWAP */ |
||
3172 | { B_MASKS(1,0), B_MASKS(2,0), B_MASKS(4,0) }, |
||
3173 | /* Normal (big-endian byte) masks - PNG format */ |
||
3174 | { B_MASKS(1,1), B_MASKS(2,1), B_MASKS(4,1) } |
||
3175 | }; |
||
3176 | |||
3177 | |||
3178 | ((display)?display_mask[png][DEPTH_INDEX(depth)][pass>>1]:\ |
||
3179 | row_mask[png][DEPTH_INDEX(depth)][pass]) |
||
3180 | |||
3181 | |||
3182 | /* This is the runtime alternative: it seems unlikely that this will |
||
3183 | * ever be either smaller or faster than the compile time approach. |
||
3184 | */ |
||
3185 | # define MASK(pass,depth,display,png)\ |
||
3186 | ((display)?B_MASK(pass,depth,png):S_MASK(pass,depth,png)) |
||
3187 | #endif /* !PNG_USE_COMPILE_TIME_MASKS */ |
||
3188 | |||
3189 | |||
3190 | * the byte mask will be 0 or 0xff, optimize these cases. row_width is |
||
3191 | * the number of pixels, but the code copies bytes, so it is necessary |
||
3192 | * to special case the end. |
||
3193 | */ |
||
3194 | png_uint_32 pixels_per_byte = 8 / pixel_depth; |
||
3195 | png_uint_32 mask; |
||
3196 | |||
3197 | |||
3198 | if (png_ptr->transformations & PNG_PACKSWAP) |
||
3199 | mask = MASK(pass, pixel_depth, display, 0); |
||
3200 | |||
3201 | |||
3202 | # endif |
||
3203 | mask = MASK(pass, pixel_depth, display, 1); |
||
3204 | |||
3205 | |||
3206 | { |
||
3207 | png_uint_32 m; |
||
3208 | |||
3209 | |||
3210 | * 32 bits because the high bits always match those in m<<24; it is, |
||
3211 | * however, essential to use OR here, not +, because of this. |
||
3212 | */ |
||
3213 | m = mask; |
||
3214 | mask = (m >> 8) | (m << 24); /* rotate right to good compilers */ |
||
3215 | m &= 0xff; |
||
3216 | |||
3217 | |||
3218 | { |
||
3219 | if (m != 0xff) |
||
3220 | *dp = (png_byte)((*dp & ~m) | (*sp & m)); |
||
3221 | else |
||
3222 | *dp = *sp; |
||
3223 | } |
||
3224 | |||
3225 | |||
3226 | * is not an exact number of bytes wide; libpng has always done |
||
3227 | * this. |
||
3228 | */ |
||
3229 | if (row_width <= pixels_per_byte) |
||
3230 | break; /* May need to restore part of the last byte */ |
||
3231 | |||
3232 | |||
3233 | ++dp; |
||
3234 | ++sp; |
||
3235 | } |
||
3236 | } |
||
3237 | |||
3238 | |||
3239 | { |
||
3240 | unsigned int bytes_to_copy, bytes_to_jump; |
||
3241 | |||
3242 | |||
3243 | if (pixel_depth & 7) |
||
3244 | png_error(png_ptr, "invalid user transform pixel depth"); |
||
3245 | |||
3246 | |||
3247 | row_width *= pixel_depth; |
||
3248 | |||
3249 | |||
3250 | * fixed number of pixels to copy then to skip. There may be a |
||
3251 | * different number of pixels to skip at the start though. |
||
3252 | */ |
||
3253 | { |
||
3254 | unsigned int offset = PNG_PASS_START_COL(pass) * pixel_depth; |
||
3255 | |||
3256 | |||
3257 | dp += offset; |
||
3258 | sp += offset; |
||
3259 | } |
||
3260 | |||
3261 | |||
3262 | if (display) |
||
3263 | { |
||
3264 | /* When doing the 'block' algorithm the pixel in the pass gets |
||
3265 | * replicated to adjacent pixels. This is why the even (0,2,4,6) |
||
3266 | * passes are skipped above - the entire expanded row is copied. |
||
3267 | */ |
||
3268 | bytes_to_copy = (1<<((6-pass)>>1)) * pixel_depth; |
||
3269 | |||
3270 | |||
3271 | if (bytes_to_copy > row_width) |
||
3272 | bytes_to_copy = row_width; |
||
3273 | } |
||
3274 | |||
3275 | |||
3276 | bytes_to_copy = pixel_depth; |
||
3277 | |||
3278 | |||
3279 | bytes_to_jump = PNG_PASS_COL_OFFSET(pass) * pixel_depth; |
||
3280 | |||
3281 | |||
3282 | * depending on the value of 'bytes_to_copy'. Special case the low |
||
3283 | * byte counts, which we know to be frequent. |
||
3284 | * |
||
3285 | * Notice that these cases all 'return' rather than 'break' - this |
||
3286 | * avoids an unnecessary test on whether to restore the last byte |
||
3287 | * below. |
||
3288 | */ |
||
3289 | switch (bytes_to_copy) |
||
3290 | { |
||
3291 | case 1: |
||
3292 | for (;;) |
||
3293 | { |
||
3294 | *dp = *sp; |
||
3295 | |||
3296 | |||
3297 | return; |
||
3298 | |||
3299 | |||
3300 | sp += bytes_to_jump; |
||
3301 | row_width -= bytes_to_jump; |
||
3302 | } |
||
3303 | |||
3304 | |||
3305 | /* There is a possibility of a partial copy at the end here; this |
||
3306 | * slows the code down somewhat. |
||
3307 | */ |
||
3308 | do |
||
3309 | { |
||
3310 | dp[0] = sp[0], dp[1] = sp[1]; |
||
3311 | |||
3312 | |||
3313 | return; |
||
3314 | |||
3315 | |||
3316 | dp += bytes_to_jump; |
||
3317 | row_width -= bytes_to_jump; |
||
3318 | } |
||
3319 | while (row_width > 1); |
||
3320 | |||
3321 | |||
3322 | *dp = *sp; |
||
3323 | return; |
||
3324 | |||
3325 | |||
3326 | /* This can only be the RGB case, so each copy is exactly one |
||
3327 | * pixel and it is not necessary to check for a partial copy. |
||
3328 | */ |
||
3329 | for(;;) |
||
3330 | { |
||
3331 | dp[0] = sp[0], dp[1] = sp[1], dp[2] = sp[2]; |
||
3332 | |||
3333 | |||
3334 | return; |
||
3335 | |||
3336 | |||
3337 | dp += bytes_to_jump; |
||
3338 | row_width -= bytes_to_jump; |
||
3339 | } |
||
3340 | |||
3341 | |||
3342 | #if PNG_ALIGN_TYPE != PNG_ALIGN_NONE |
||
3343 | /* Check for double byte alignment and, if possible, use a |
||
3344 | * 16-bit copy. Don't attempt this for narrow images - ones that |
||
3345 | * are less than an interlace panel wide. Don't attempt it for |
||
3346 | * wide bytes_to_copy either - use the memcpy there. |
||
3347 | */ |
||
3348 | if (bytes_to_copy < 16 /*else use memcpy*/ && |
||
3349 | png_isaligned(dp, png_uint_16) && |
||
3350 | png_isaligned(sp, png_uint_16) && |
||
3351 | bytes_to_copy % (sizeof (png_uint_16)) == 0 && |
||
3352 | bytes_to_jump % (sizeof (png_uint_16)) == 0) |
||
3353 | { |
||
3354 | /* Everything is aligned for png_uint_16 copies, but try for |
||
3355 | * png_uint_32 first. |
||
3356 | */ |
||
3357 | if (png_isaligned(dp, png_uint_32) && |
||
3358 | png_isaligned(sp, png_uint_32) && |
||
3359 | bytes_to_copy % (sizeof (png_uint_32)) == 0 && |
||
3360 | bytes_to_jump % (sizeof (png_uint_32)) == 0) |
||
3361 | { |
||
3362 | png_uint_32p dp32 = png_aligncast(png_uint_32p,dp); |
||
3363 | png_const_uint_32p sp32 = png_aligncastconst( |
||
3364 | png_const_uint_32p, sp); |
||
3365 | size_t skip = (bytes_to_jump-bytes_to_copy) / |
||
3366 | (sizeof (png_uint_32)); |
||
3367 | |||
3368 | |||
3369 | { |
||
3370 | size_t c = bytes_to_copy; |
||
3371 | do |
||
3372 | { |
||
3373 | *dp32++ = *sp32++; |
||
3374 | c -= (sizeof (png_uint_32)); |
||
3375 | } |
||
3376 | while (c > 0); |
||
3377 | |||
3378 | |||
3379 | return; |
||
3380 | |||
3381 | |||
3382 | sp32 += skip; |
||
3383 | row_width -= bytes_to_jump; |
||
3384 | } |
||
3385 | while (bytes_to_copy <= row_width); |
||
3386 | |||
3387 | |||
3388 | * There will be 1-3 bytes left to copy, so don't try the |
||
3389 | * 16-bit loop below. |
||
3390 | */ |
||
3391 | dp = (png_bytep)dp32; |
||
3392 | sp = (png_const_bytep)sp32; |
||
3393 | do |
||
3394 | *dp++ = *sp++; |
||
3395 | while (--row_width > 0); |
||
3396 | return; |
||
3397 | } |
||
3398 | |||
3399 | |||
3400 | * not too large. |
||
3401 | */ |
||
3402 | else |
||
3403 | { |
||
3404 | png_uint_16p dp16 = png_aligncast(png_uint_16p, dp); |
||
3405 | png_const_uint_16p sp16 = png_aligncastconst( |
||
3406 | png_const_uint_16p, sp); |
||
3407 | size_t skip = (bytes_to_jump-bytes_to_copy) / |
||
3408 | (sizeof (png_uint_16)); |
||
3409 | |||
3410 | |||
3411 | { |
||
3412 | size_t c = bytes_to_copy; |
||
3413 | do |
||
3414 | { |
||
3415 | *dp16++ = *sp16++; |
||
3416 | c -= (sizeof (png_uint_16)); |
||
3417 | } |
||
3418 | while (c > 0); |
||
3419 | |||
3420 | |||
3421 | return; |
||
3422 | |||
3423 | |||
3424 | sp16 += skip; |
||
3425 | row_width -= bytes_to_jump; |
||
3426 | } |
||
3427 | while (bytes_to_copy <= row_width); |
||
3428 | |||
3429 | |||
3430 | dp = (png_bytep)dp16; |
||
3431 | sp = (png_const_bytep)sp16; |
||
3432 | do |
||
3433 | *dp++ = *sp++; |
||
3434 | while (--row_width > 0); |
||
3435 | return; |
||
3436 | } |
||
3437 | } |
||
3438 | #endif /* PNG_ALIGN_ code */ |
||
3439 | |||
3440 | |||
3441 | for (;;) |
||
3442 | { |
||
3443 | memcpy(dp, sp, bytes_to_copy); |
||
3444 | |||
3445 | |||
3446 | return; |
||
3447 | |||
3448 | |||
3449 | dp += bytes_to_jump; |
||
3450 | row_width -= bytes_to_jump; |
||
3451 | if (bytes_to_copy > row_width) |
||
3452 | bytes_to_copy = row_width; |
||
3453 | } |
||
3454 | } |
||
3455 | |||
3456 | |||
3457 | } /* pixel_depth >= 8 */ |
||
3458 | |||
3459 | |||
3460 | } |
||
3461 | else |
||
3462 | #endif |
||
3463 | |||
3464 | |||
3465 | * from the temporary row buffer (notice that this overwrites the end of the |
||
3466 | * destination row if it is a partial byte.) |
||
3467 | */ |
||
3468 | memcpy(dp, sp, PNG_ROWBYTES(pixel_depth, row_width)); |
||
3469 | |||
3470 | |||
3471 | if (end_ptr != NULL) |
||
3472 | *end_ptr = (png_byte)((end_byte & end_mask) | (*end_ptr & ~end_mask)); |
||
3473 | } |
||
3474 | |||
3475 | |||
3476 | void /* PRIVATE */ |
||
3477 | png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, |
||
3478 | png_uint_32 transformations /* Because these may affect the byte layout */) |
||
3479 | { |
||
3480 | /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
||
3481 | /* Offset to next interlace block */ |
||
3482 | static PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
||
3483 | |||
3484 | |||
3485 | if (row != NULL && row_info != NULL) |
||
3486 | { |
||
3487 | png_uint_32 final_width; |
||
3488 | |||
3489 | |||
3490 | |||
3491 | |||
3492 | { |
||
3493 | case 1: |
||
3494 | { |
||
3495 | png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3); |
||
3496 | png_bytep dp = row + (png_size_t)((final_width - 1) >> 3); |
||
3497 | int sshift, dshift; |
||
3498 | int s_start, s_end, s_inc; |
||
3499 | int jstop = png_pass_inc[pass]; |
||
3500 | png_byte v; |
||
3501 | png_uint_32 i; |
||
3502 | int j; |
||
3503 | |||
3504 | |||
3505 | if (transformations & PNG_PACKSWAP) |
||
3506 | { |
||
3507 | sshift = (int)((row_info->width + 7) & 0x07); |
||
3508 | dshift = (int)((final_width + 7) & 0x07); |
||
3509 | s_start = 7; |
||
3510 | s_end = 0; |
||
3511 | s_inc = -1; |
||
3512 | } |
||
3513 | |||
3514 | |||
3515 | #endif |
||
3516 | { |
||
3517 | sshift = 7 - (int)((row_info->width + 7) & 0x07); |
||
3518 | dshift = 7 - (int)((final_width + 7) & 0x07); |
||
3519 | s_start = 0; |
||
3520 | s_end = 7; |
||
3521 | s_inc = 1; |
||
3522 | } |
||
3523 | |||
3524 | |||
3525 | { |
||
3526 | v = (png_byte)((*sp >> sshift) & 0x01); |
||
3527 | for (j = 0; j < jstop; j++) |
||
3528 | { |
||
3529 | unsigned int tmp = *dp & (0x7f7f >> (7 - dshift)); |
||
3530 | tmp |= v << dshift; |
||
3531 | *dp = (png_byte)(tmp & 0xff); |
||
3532 | |||
3533 | |||
3534 | { |
||
3535 | dshift = s_start; |
||
3536 | dp--; |
||
3537 | } |
||
3538 | |||
3539 | |||
3540 | dshift += s_inc; |
||
3541 | } |
||
3542 | |||
3543 | |||
3544 | { |
||
3545 | sshift = s_start; |
||
3546 | sp--; |
||
3547 | } |
||
3548 | |||
3549 | |||
3550 | sshift += s_inc; |
||
3551 | } |
||
3552 | break; |
||
3553 | } |
||
3554 | |||
3555 | |||
3556 | { |
||
3557 | png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2); |
||
3558 | png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2); |
||
3559 | int sshift, dshift; |
||
3560 | int s_start, s_end, s_inc; |
||
3561 | int jstop = png_pass_inc[pass]; |
||
3562 | png_uint_32 i; |
||
3563 | |||
3564 | |||
3565 | if (transformations & PNG_PACKSWAP) |
||
3566 | { |
||
3567 | sshift = (int)(((row_info->width + 3) & 0x03) << 1); |
||
3568 | dshift = (int)(((final_width + 3) & 0x03) << 1); |
||
3569 | s_start = 6; |
||
3570 | s_end = 0; |
||
3571 | s_inc = -2; |
||
3572 | } |
||
3573 | |||
3574 | |||
3575 | #endif |
||
3576 | { |
||
3577 | sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1); |
||
3578 | dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1); |
||
3579 | s_start = 0; |
||
3580 | s_end = 6; |
||
3581 | s_inc = 2; |
||
3582 | } |
||
3583 | |||
3584 | |||
3585 | { |
||
3586 | png_byte v; |
||
3587 | int j; |
||
3588 | |||
3589 | |||
3590 | for (j = 0; j < jstop; j++) |
||
3591 | { |
||
3592 | unsigned int tmp = *dp & (0x3f3f >> (6 - dshift)); |
||
3593 | tmp |= v << dshift; |
||
3594 | *dp = (png_byte)(tmp & 0xff); |
||
3595 | |||
3596 | |||
3597 | { |
||
3598 | dshift = s_start; |
||
3599 | dp--; |
||
3600 | } |
||
3601 | |||
3602 | |||
3603 | dshift += s_inc; |
||
3604 | } |
||
3605 | |||
3606 | |||
3607 | { |
||
3608 | sshift = s_start; |
||
3609 | sp--; |
||
3610 | } |
||
3611 | |||
3612 | |||
3613 | sshift += s_inc; |
||
3614 | } |
||
3615 | break; |
||
3616 | } |
||
3617 | |||
3618 | |||
3619 | { |
||
3620 | png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1); |
||
3621 | png_bytep dp = row + (png_size_t)((final_width - 1) >> 1); |
||
3622 | int sshift, dshift; |
||
3623 | int s_start, s_end, s_inc; |
||
3624 | png_uint_32 i; |
||
3625 | int jstop = png_pass_inc[pass]; |
||
3626 | |||
3627 | |||
3628 | if (transformations & PNG_PACKSWAP) |
||
3629 | { |
||
3630 | sshift = (int)(((row_info->width + 1) & 0x01) << 2); |
||
3631 | dshift = (int)(((final_width + 1) & 0x01) << 2); |
||
3632 | s_start = 4; |
||
3633 | s_end = 0; |
||
3634 | s_inc = -4; |
||
3635 | } |
||
3636 | |||
3637 | |||
3638 | #endif |
||
3639 | { |
||
3640 | sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2); |
||
3641 | dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2); |
||
3642 | s_start = 0; |
||
3643 | s_end = 4; |
||
3644 | s_inc = 4; |
||
3645 | } |
||
3646 | |||
3647 | |||
3648 | { |
||
3649 | png_byte v = (png_byte)((*sp >> sshift) & 0x0f); |
||
3650 | int j; |
||
3651 | |||
3652 | |||
3653 | { |
||
3654 | unsigned int tmp = *dp & (0xf0f >> (4 - dshift)); |
||
3655 | tmp |= v << dshift; |
||
3656 | *dp = (png_byte)(tmp & 0xff); |
||
3657 | |||
3658 | |||
3659 | { |
||
3660 | dshift = s_start; |
||
3661 | dp--; |
||
3662 | } |
||
3663 | |||
3664 | |||
3665 | dshift += s_inc; |
||
3666 | } |
||
3667 | |||
3668 | |||
3669 | { |
||
3670 | sshift = s_start; |
||
3671 | sp--; |
||
3672 | } |
||
3673 | |||
3674 | |||
3675 | sshift += s_inc; |
||
3676 | } |
||
3677 | break; |
||
3678 | } |
||
3679 | |||
3680 | |||
3681 | { |
||
3682 | png_size_t pixel_bytes = (row_info->pixel_depth >> 3); |
||
3683 | |||
3684 | |||
3685 | * pixel_bytes; |
||
3686 | |||
3687 | |||
3688 | |||
3689 | |||
3690 | png_uint_32 i; |
||
3691 | |||
3692 | |||
3693 | { |
||
3694 | png_byte v[8]; /* SAFE; pixel_depth does not exceed 64 */ |
||
3695 | int j; |
||
3696 | |||
3697 | |||
3698 | |||
3699 | |||
3700 | { |
||
3701 | memcpy(dp, v, pixel_bytes); |
||
3702 | dp -= pixel_bytes; |
||
3703 | } |
||
3704 | |||
3705 | |||
3706 | } |
||
3707 | break; |
||
3708 | } |
||
3709 | } |
||
3710 | |||
3711 | |||
3712 | row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width); |
||
3713 | } |
||
3714 | #ifndef PNG_READ_PACKSWAP_SUPPORTED |
||
3715 | PNG_UNUSED(transformations) /* Silence compiler warning */ |
||
3716 | #endif |
||
3717 | } |
||
3718 | #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
||
3719 | |||
3720 | |||
3721 | png_read_filter_row_sub(png_row_infop row_info, png_bytep row, |
||
3722 | png_const_bytep prev_row) |
||
3723 | { |
||
3724 | png_size_t i; |
||
3725 | png_size_t istop = row_info->rowbytes; |
||
3726 | unsigned int bpp = (row_info->pixel_depth + 7) >> 3; |
||
3727 | png_bytep rp = row + bpp; |
||
3728 | |||
3729 | |||
3730 | |||
3731 | |||
3732 | { |
||
3733 | *rp = (png_byte)(((int)(*rp) + (int)(*(rp-bpp))) & 0xff); |
||
3734 | rp++; |
||
3735 | } |
||
3736 | } |
||
3737 | |||
3738 | |||
3739 | png_read_filter_row_up(png_row_infop row_info, png_bytep row, |
||
3740 | png_const_bytep prev_row) |
||
3741 | { |
||
3742 | png_size_t i; |
||
3743 | png_size_t istop = row_info->rowbytes; |
||
3744 | png_bytep rp = row; |
||
3745 | png_const_bytep pp = prev_row; |
||
3746 | |||
3747 | |||
3748 | { |
||
3749 | *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff); |
||
3750 | rp++; |
||
3751 | } |
||
3752 | } |
||
3753 | |||
3754 | |||
3755 | png_read_filter_row_avg(png_row_infop row_info, png_bytep row, |
||
3756 | png_const_bytep prev_row) |
||
3757 | { |
||
3758 | png_size_t i; |
||
3759 | png_bytep rp = row; |
||
3760 | png_const_bytep pp = prev_row; |
||
3761 | unsigned int bpp = (row_info->pixel_depth + 7) >> 3; |
||
3762 | png_size_t istop = row_info->rowbytes - bpp; |
||
3763 | |||
3764 | |||
3765 | { |
||
3766 | *rp = (png_byte)(((int)(*rp) + |
||
3767 | ((int)(*pp++) / 2 )) & 0xff); |
||
3768 | |||
3769 | |||
3770 | } |
||
3771 | |||
3772 | |||
3773 | { |
||
3774 | *rp = (png_byte)(((int)(*rp) + |
||
3775 | (int)(*pp++ + *(rp-bpp)) / 2 ) & 0xff); |
||
3776 | |||
3777 | |||
3778 | } |
||
3779 | } |
||
3780 | |||
3781 | |||
3782 | png_read_filter_row_paeth_1byte_pixel(png_row_infop row_info, png_bytep row, |
||
3783 | png_const_bytep prev_row) |
||
3784 | { |
||
3785 | png_bytep rp_end = row + row_info->rowbytes; |
||
3786 | int a, c; |
||
3787 | |||
3788 | |||
3789 | c = *prev_row++; |
||
3790 | a = *row + c; |
||
3791 | *row++ = (png_byte)a; |
||
3792 | |||
3793 | |||
3794 | while (row < rp_end) |
||
3795 | { |
||
3796 | int b, pa, pb, pc, p; |
||
3797 | |||
3798 | |||
3799 | b = *prev_row++; |
||
3800 | |||
3801 | |||
3802 | pc = a - c; |
||
3803 | |||
3804 | |||
3805 | pa = abs(p); |
||
3806 | pb = abs(pc); |
||
3807 | pc = abs(p + pc); |
||
3808 | # else |
||
3809 | pa = p < 0 ? -p : p; |
||
3810 | pb = pc < 0 ? -pc : pc; |
||
3811 | pc = (p + pc) < 0 ? -(p + pc) : p + pc; |
||
3812 | # endif |
||
3813 | |||
3814 | |||
3815 | * ones in the case of a tie. |
||
3816 | */ |
||
3817 | if (pb < pa) pa = pb, a = b; |
||
3818 | if (pc < pa) a = c; |
||
3819 | |||
3820 | |||
3821 | * for the next time round the loop |
||
3822 | */ |
||
3823 | c = b; |
||
3824 | a += *row; |
||
3825 | *row++ = (png_byte)a; |
||
3826 | } |
||
3827 | } |
||
3828 | |||
3829 | |||
3830 | png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row, |
||
3831 | png_const_bytep prev_row) |
||
3832 | { |
||
3833 | int bpp = (row_info->pixel_depth + 7) >> 3; |
||
3834 | png_bytep rp_end = row + bpp; |
||
3835 | |||
3836 | |||
3837 | * because there is only one candidate predictor for the first row). |
||
3838 | */ |
||
3839 | while (row < rp_end) |
||
3840 | { |
||
3841 | int a = *row + *prev_row++; |
||
3842 | *row++ = (png_byte)a; |
||
3843 | } |
||
3844 | |||
3845 | |||
3846 | rp_end += row_info->rowbytes - bpp; |
||
3847 | |||
3848 | |||
3849 | { |
||
3850 | int a, b, c, pa, pb, pc, p; |
||
3851 | |||
3852 | |||
3853 | a = *(row - bpp); |
||
3854 | b = *prev_row++; |
||
3855 | |||
3856 | |||
3857 | pc = a - c; |
||
3858 | |||
3859 | |||
3860 | pa = abs(p); |
||
3861 | pb = abs(pc); |
||
3862 | pc = abs(p + pc); |
||
3863 | # else |
||
3864 | pa = p < 0 ? -p : p; |
||
3865 | pb = pc < 0 ? -pc : pc; |
||
3866 | pc = (p + pc) < 0 ? -(p + pc) : p + pc; |
||
3867 | # endif |
||
3868 | |||
3869 | |||
3870 | if (pc < pa) a = c; |
||
3871 | |||
3872 | |||
3873 | a += *row; |
||
3874 | *row++ = (png_byte)a; |
||
3875 | } |
||
3876 | } |
||
3877 | |||
3878 | |||
3879 | png_init_filter_functions(png_structrp pp) |
||
3880 | /* This function is called once for every PNG image (except for PNG images |
||
3881 | * that only use PNG_FILTER_VALUE_NONE for all rows) to set the |
||
3882 | * implementations required to reverse the filtering of PNG rows. Reversing |
||
3883 | * the filter is the first transformation performed on the row data. It is |
||
3884 | * performed in place, therefore an implementation can be selected based on |
||
3885 | * the image pixel format. If the implementation depends on image width then |
||
3886 | * take care to ensure that it works correctly if the image is interlaced - |
||
3887 | * interlacing causes the actual row width to vary. |
||
3888 | */ |
||
3889 | { |
||
3890 | unsigned int bpp = (pp->pixel_depth + 7) >> 3; |
||
3891 | |||
3892 | |||
3893 | pp->read_filter[PNG_FILTER_VALUE_UP-1] = png_read_filter_row_up; |
||
3894 | pp->read_filter[PNG_FILTER_VALUE_AVG-1] = png_read_filter_row_avg; |
||
3895 | if (bpp == 1) |
||
3896 | pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = |
||
3897 | png_read_filter_row_paeth_1byte_pixel; |
||
3898 | else |
||
3899 | pp->read_filter[PNG_FILTER_VALUE_PAETH-1] = |
||
3900 | png_read_filter_row_paeth_multibyte_pixel; |
||
3901 | |||
3902 | |||
3903 | /* To use this define PNG_FILTER_OPTIMIZATIONS as the name of a function to |
||
3904 | * call to install hardware optimizations for the above functions; simply |
||
3905 | * replace whatever elements of the pp->read_filter[] array with a hardware |
||
3906 | * specific (or, for that matter, generic) optimization. |
||
3907 | * |
||
3908 | * To see an example of this examine what configure.ac does when |
||
3909 | * --enable-arm-neon is specified on the command line. |
||
3910 | */ |
||
3911 | PNG_FILTER_OPTIMIZATIONS(pp, bpp); |
||
3912 | #endif |
||
3913 | } |
||
3914 | |||
3915 | |||
3916 | png_read_filter_row(png_structrp pp, png_row_infop row_info, png_bytep row, |
||
3917 | png_const_bytep prev_row, int filter) |
||
3918 | { |
||
3919 | /* OPTIMIZATION: DO NOT MODIFY THIS FUNCTION, instead #define |
||
3920 | * PNG_FILTER_OPTIMIZATIONS to a function that overrides the generic |
||
3921 | * implementations. See png_init_filter_functions above. |
||
3922 | */ |
||
3923 | if (filter > PNG_FILTER_VALUE_NONE && filter < PNG_FILTER_VALUE_LAST) |
||
3924 | { |
||
3925 | if (pp->read_filter[0] == NULL) |
||
3926 | png_init_filter_functions(pp); |
||
3927 | |||
3928 | |||
3929 | } |
||
3930 | } |
||
3931 | |||
3932 | |||
3933 | void /* PRIVATE */ |
||
3934 | png_read_IDAT_data(png_structrp png_ptr, png_bytep output, |
||
3935 | png_alloc_size_t avail_out) |
||
3936 | { |
||
3937 | /* Loop reading IDATs and decompressing the result into output[avail_out] */ |
||
3938 | png_ptr->zstream.next_out = output; |
||
3939 | png_ptr->zstream.avail_out = 0; /* safety: set below */ |
||
3940 | |||
3941 | |||
3942 | avail_out = 0; |
||
3943 | |||
3944 | |||
3945 | { |
||
3946 | int ret; |
||
3947 | png_byte tmpbuf[PNG_INFLATE_BUF_SIZE]; |
||
3948 | |||
3949 | |||
3950 | { |
||
3951 | uInt avail_in; |
||
3952 | png_bytep buffer; |
||
3953 | |||
3954 | |||
3955 | { |
||
3956 | png_crc_finish(png_ptr, 0); |
||
3957 | |||
3958 | |||
3959 | /* This is an error even in the 'check' case because the code just |
||
3960 | * consumed a non-IDAT header. |
||
3961 | */ |
||
3962 | if (png_ptr->chunk_name != png_IDAT) |
||
3963 | png_error(png_ptr, "Not enough image data"); |
||
3964 | } |
||
3965 | |||
3966 | |||
3967 | |||
3968 | |||
3969 | avail_in = (uInt)png_ptr->idat_size; |
||
3970 | |||
3971 | |||
3972 | * to minimize memory usage by causing lots of re-allocs, but |
||
3973 | * realistically doing IDAT_read_size re-allocs is not likely to be a |
||
3974 | * big problem. |
||
3975 | */ |
||
3976 | buffer = png_read_buffer(png_ptr, avail_in, 0/*error*/); |
||
3977 | |||
3978 | |||
3979 | png_ptr->idat_size -= avail_in; |
||
3980 | |||
3981 | |||
3982 | png_ptr->zstream.avail_in = avail_in; |
||
3983 | } |
||
3984 | |||
3985 | |||
3986 | if (output != NULL) /* standard read */ |
||
3987 | { |
||
3988 | uInt out = ZLIB_IO_MAX; |
||
3989 | |||
3990 | |||
3991 | out = (uInt)avail_out; |
||
3992 | |||
3993 | |||
3994 | png_ptr->zstream.avail_out = out; |
||
3995 | } |
||
3996 | |||
3997 | |||
3998 | { |
||
3999 | png_ptr->zstream.next_out = tmpbuf; |
||
4000 | png_ptr->zstream.avail_out = (sizeof tmpbuf); |
||
4001 | } |
||
4002 | |||
4003 | |||
4004 | * process. If the LZ stream is truncated the sequential reader will |
||
4005 | * terminally damage the stream, above, by reading the chunk header of the |
||
4006 | * following chunk (it then exits with png_error). |
||
4007 | * |
||
4008 | * TODO: deal more elegantly with truncated IDAT lists. |
||
4009 | */ |
||
4010 | ret = inflate(&png_ptr->zstream, Z_NO_FLUSH); |
||
4011 | |||
4012 | |||
4013 | if (output != NULL) |
||
4014 | avail_out += png_ptr->zstream.avail_out; |
||
4015 | |||
4016 | |||
4017 | avail_out += (sizeof tmpbuf) - png_ptr->zstream.avail_out; |
||
4018 | |||
4019 | |||
4020 | |||
4021 | |||
4022 | { |
||
4023 | /* Do this for safety; we won't read any more into this row. */ |
||
4024 | png_ptr->zstream.next_out = NULL; |
||
4025 | |||
4026 | |||
4027 | png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; |
||
4028 | |||
4029 | |||
4030 | png_chunk_benign_error(png_ptr, "Extra compressed data"); |
||
4031 | break; |
||
4032 | } |
||
4033 | |||
4034 | |||
4035 | { |
||
4036 | png_zstream_error(png_ptr, ret); |
||
4037 | |||
4038 | |||
4039 | png_chunk_error(png_ptr, png_ptr->zstream.msg); |
||
4040 | |||
4041 | |||
4042 | { |
||
4043 | png_chunk_benign_error(png_ptr, png_ptr->zstream.msg); |
||
4044 | return; |
||
4045 | } |
||
4046 | } |
||
4047 | } while (avail_out > 0); |
||
4048 | |||
4049 | |||
4050 | { |
||
4051 | /* The stream ended before the image; this is the same as too few IDATs so |
||
4052 | * should be handled the same way. |
||
4053 | */ |
||
4054 | if (output != NULL) |
||
4055 | png_error(png_ptr, "Not enough image data"); |
||
4056 | |||
4057 | |||
4058 | png_chunk_benign_error(png_ptr, "Too much image data"); |
||
4059 | } |
||
4060 | } |
||
4061 | |||
4062 | |||
4063 | png_read_finish_IDAT(png_structrp png_ptr) |
||
4064 | { |
||
4065 | /* We don't need any more data and the stream should have ended, however the |
||
4066 | * LZ end code may actually not have been processed. In this case we must |
||
4067 | * read it otherwise stray unread IDAT data or, more likely, an IDAT chunk |
||
4068 | * may still remain to be consumed. |
||
4069 | */ |
||
4070 | if (!(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED)) |
||
4071 | { |
||
4072 | /* The NULL causes png_read_IDAT_data to swallow any remaining bytes in |
||
4073 | * the compressed stream, but the stream may be damaged too, so even after |
||
4074 | * this call we may need to terminate the zstream ownership. |
||
4075 | */ |
||
4076 | png_read_IDAT_data(png_ptr, NULL, 0); |
||
4077 | png_ptr->zstream.next_out = NULL; /* safety */ |
||
4078 | |||
4079 | |||
4080 | * done. |
||
4081 | */ |
||
4082 | if (!(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED)) |
||
4083 | { |
||
4084 | png_ptr->mode |= PNG_AFTER_IDAT; |
||
4085 | png_ptr->flags |= PNG_FLAG_ZSTREAM_ENDED; |
||
4086 | } |
||
4087 | } |
||
4088 | |||
4089 | |||
4090 | * of the final IDAT chunk. |
||
4091 | */ |
||
4092 | if (png_ptr->zowner == png_IDAT) |
||
4093 | { |
||
4094 | /* Always do this; the pointers otherwise point into the read buffer. */ |
||
4095 | png_ptr->zstream.next_in = NULL; |
||
4096 | png_ptr->zstream.avail_in = 0; |
||
4097 | |||
4098 | |||
4099 | png_ptr->zowner = 0; |
||
4100 | |||
4101 | |||
4102 | * are always in or at the end of an IDAT chunk, so we always need to do a |
||
4103 | * crc_finish here. If idat_size is non-zero we also need to read the |
||
4104 | * spurious bytes at the end of the chunk now. |
||
4105 | */ |
||
4106 | (void)png_crc_finish(png_ptr, png_ptr->idat_size); |
||
4107 | } |
||
4108 | } |
||
4109 | |||
4110 | |||
4111 | png_read_finish_row(png_structrp png_ptr) |
||
4112 | { |
||
4113 | #ifdef PNG_READ_INTERLACING_SUPPORTED |
||
4114 | /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
||
4115 | |||
4116 | |||
4117 | static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
||
4118 | |||
4119 | |||
4120 | static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
||
4121 | |||
4122 | |||
4123 | static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; |
||
4124 | |||
4125 | |||
4126 | static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; |
||
4127 | #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
||
4128 | |||
4129 | |||
4130 | png_ptr->row_number++; |
||
4131 | if (png_ptr->row_number < png_ptr->num_rows) |
||
4132 | return; |
||
4133 | |||
4134 | |||
4135 | if (png_ptr->interlaced) |
||
4136 | { |
||
4137 | png_ptr->row_number = 0; |
||
4138 | |||
4139 | |||
4140 | * read-ahead of the next row's filter byte. |
||
4141 | */ |
||
4142 | memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1); |
||
4143 | |||
4144 | |||
4145 | { |
||
4146 | png_ptr->pass++; |
||
4147 | |||
4148 | |||
4149 | break; |
||
4150 | |||
4151 | |||
4152 | png_pass_inc[png_ptr->pass] - 1 - |
||
4153 | png_pass_start[png_ptr->pass]) / |
||
4154 | png_pass_inc[png_ptr->pass]; |
||
4155 | |||
4156 | |||
4157 | { |
||
4158 | png_ptr->num_rows = (png_ptr->height + |
||
4159 | png_pass_yinc[png_ptr->pass] - 1 - |
||
4160 | png_pass_ystart[png_ptr->pass]) / |
||
4161 | png_pass_yinc[png_ptr->pass]; |
||
4162 | } |
||
4163 | |||
4164 | |||
4165 | break; /* libpng deinterlacing sees every row */ |
||
4166 | |||
4167 | |||
4168 | |||
4169 | |||
4170 | return; |
||
4171 | } |
||
4172 | #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
||
4173 | |||
4174 | |||
4175 | png_read_finish_IDAT(png_ptr); |
||
4176 | } |
||
4177 | #endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ |
||
4178 | |||
4179 | |||
4180 | png_read_start_row(png_structrp png_ptr) |
||
4181 | { |
||
4182 | #ifdef PNG_READ_INTERLACING_SUPPORTED |
||
4183 | /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
||
4184 | |||
4185 | |||
4186 | static PNG_CONST png_byte png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
||
4187 | |||
4188 | |||
4189 | static PNG_CONST png_byte png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
||
4190 | |||
4191 | |||
4192 | static PNG_CONST png_byte png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; |
||
4193 | |||
4194 | |||
4195 | static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; |
||
4196 | #endif |
||
4197 | |||
4198 | |||
4199 | png_size_t row_bytes; |
||
4200 | |||
4201 | |||
4202 | |||
4203 | |||
4204 | png_init_read_transformations(png_ptr); |
||
4205 | #endif |
||
4206 | #ifdef PNG_READ_INTERLACING_SUPPORTED |
||
4207 | if (png_ptr->interlaced) |
||
4208 | { |
||
4209 | if (!(png_ptr->transformations & PNG_INTERLACE)) |
||
4210 | png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 - |
||
4211 | png_pass_ystart[0]) / png_pass_yinc[0]; |
||
4212 | |||
4213 | |||
4214 | png_ptr->num_rows = png_ptr->height; |
||
4215 | |||
4216 | |||
4217 | png_pass_inc[png_ptr->pass] - 1 - |
||
4218 | png_pass_start[png_ptr->pass]) / |
||
4219 | png_pass_inc[png_ptr->pass]; |
||
4220 | } |
||
4221 | |||
4222 | |||
4223 | #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
||
4224 | { |
||
4225 | png_ptr->num_rows = png_ptr->height; |
||
4226 | png_ptr->iwidth = png_ptr->width; |
||
4227 | } |
||
4228 | |||
4229 | |||
4230 | |||
4231 | |||
4232 | * calculations to calculate the final pixel depth, then |
||
4233 | * png_do_read_transforms actually does the transforms. This means that the |
||
4234 | * code which effectively calculates this value is actually repeated in three |
||
4235 | * separate places. They must all match. Innocent changes to the order of |
||
4236 | * transformations can and will break libpng in a way that causes memory |
||
4237 | * overwrites. |
||
4238 | * |
||
4239 | * TODO: fix this. |
||
4240 | */ |
||
4241 | #ifdef PNG_READ_PACK_SUPPORTED |
||
4242 | if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8) |
||
4243 | max_pixel_depth = 8; |
||
4244 | #endif |
||
4245 | |||
4246 | |||
4247 | if (png_ptr->transformations & PNG_EXPAND) |
||
4248 | { |
||
4249 | if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
||
4250 | { |
||
4251 | if (png_ptr->num_trans) |
||
4252 | max_pixel_depth = 32; |
||
4253 | |||
4254 | |||
4255 | max_pixel_depth = 24; |
||
4256 | } |
||
4257 | |||
4258 | |||
4259 | { |
||
4260 | if (max_pixel_depth < 8) |
||
4261 | max_pixel_depth = 8; |
||
4262 | |||
4263 | |||
4264 | max_pixel_depth *= 2; |
||
4265 | } |
||
4266 | |||
4267 | |||
4268 | { |
||
4269 | if (png_ptr->num_trans) |
||
4270 | { |
||
4271 | max_pixel_depth *= 4; |
||
4272 | max_pixel_depth /= 3; |
||
4273 | } |
||
4274 | } |
||
4275 | } |
||
4276 | #endif |
||
4277 | |||
4278 | |||
4279 | if (png_ptr->transformations & PNG_EXPAND_16) |
||
4280 | { |
||
4281 | # ifdef PNG_READ_EXPAND_SUPPORTED |
||
4282 | /* In fact it is an error if it isn't supported, but checking is |
||
4283 | * the safe way. |
||
4284 | */ |
||
4285 | if (png_ptr->transformations & PNG_EXPAND) |
||
4286 | { |
||
4287 | if (png_ptr->bit_depth < 16) |
||
4288 | max_pixel_depth *= 2; |
||
4289 | } |
||
4290 | else |
||
4291 | # endif |
||
4292 | png_ptr->transformations &= ~PNG_EXPAND_16; |
||
4293 | } |
||
4294 | #endif |
||
4295 | |||
4296 | |||
4297 | if (png_ptr->transformations & (PNG_FILLER)) |
||
4298 | { |
||
4299 | if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) |
||
4300 | { |
||
4301 | if (max_pixel_depth <= 8) |
||
4302 | max_pixel_depth = 16; |
||
4303 | |||
4304 | |||
4305 | max_pixel_depth = 32; |
||
4306 | } |
||
4307 | |||
4308 | |||
4309 | png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
||
4310 | { |
||
4311 | if (max_pixel_depth <= 32) |
||
4312 | max_pixel_depth = 32; |
||
4313 | |||
4314 | |||
4315 | max_pixel_depth = 64; |
||
4316 | } |
||
4317 | } |
||
4318 | #endif |
||
4319 | |||
4320 | |||
4321 | if (png_ptr->transformations & PNG_GRAY_TO_RGB) |
||
4322 | { |
||
4323 | if ( |
||
4324 | #ifdef PNG_READ_EXPAND_SUPPORTED |
||
4325 | (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) || |
||
4326 | #endif |
||
4327 | #ifdef PNG_READ_FILLER_SUPPORTED |
||
4328 | (png_ptr->transformations & (PNG_FILLER)) || |
||
4329 | #endif |
||
4330 | png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
||
4331 | { |
||
4332 | if (max_pixel_depth <= 16) |
||
4333 | max_pixel_depth = 32; |
||
4334 | |||
4335 | |||
4336 | max_pixel_depth = 64; |
||
4337 | } |
||
4338 | |||
4339 | |||
4340 | { |
||
4341 | if (max_pixel_depth <= 8) |
||
4342 | { |
||
4343 | if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
||
4344 | max_pixel_depth = 32; |
||
4345 | |||
4346 | |||
4347 | max_pixel_depth = 24; |
||
4348 | } |
||
4349 | |||
4350 | |||
4351 | max_pixel_depth = 64; |
||
4352 | |||
4353 | |||
4354 | max_pixel_depth = 48; |
||
4355 | } |
||
4356 | } |
||
4357 | #endif |
||
4358 | |||
4359 | |||
4360 | defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) |
||
4361 | if (png_ptr->transformations & PNG_USER_TRANSFORM) |
||
4362 | { |
||
4363 | int user_pixel_depth = png_ptr->user_transform_depth * |
||
4364 | png_ptr->user_transform_channels; |
||
4365 | |||
4366 | |||
4367 | max_pixel_depth = user_pixel_depth; |
||
4368 | } |
||
4369 | #endif |
||
4370 | |||
4371 | |||
4372 | * code. |
||
4373 | */ |
||
4374 | png_ptr->maximum_pixel_depth = (png_byte)max_pixel_depth; |
||
4375 | png_ptr->transformed_pixel_depth = 0; /* calculated on demand */ |
||
4376 | |||
4377 | |||
4378 | * for interlacing |
||
4379 | */ |
||
4380 | row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7)); |
||
4381 | /* Calculate the maximum bytes needed, adding a byte and a pixel |
||
4382 | * for safety's sake |
||
4383 | */ |
||
4384 | row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) + |
||
4385 | 1 + ((max_pixel_depth + 7) >> 3); |
||
4386 | |||
4387 | |||
4388 | if (row_bytes > (png_uint_32)65536L) |
||
4389 | png_error(png_ptr, "This image requires a row greater than 64KB"); |
||
4390 | #endif |
||
4391 | |||
4392 | |||
4393 | { |
||
4394 | png_free(png_ptr, png_ptr->big_row_buf); |
||
4395 | png_free(png_ptr, png_ptr->big_prev_row); |
||
4396 | |||
4397 | |||
4398 | png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr, |
||
4399 | row_bytes + 48); |
||
4400 | |||
4401 | |||
4402 | png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 48); |
||
4403 | |||
4404 | |||
4405 | |||
4406 | |||
4407 | /* Use 16-byte aligned memory for row_buf with at least 16 bytes |
||
4408 | * of padding before and after row_buf; treat prev_row similarly. |
||
4409 | * NOTE: the alignment is to the start of the pixels, one beyond the start |
||
4410 | * of the buffer, because of the filter byte. Prior to libpng 1.5.6 this |
||
4411 | * was incorrect; the filter byte was aligned, which had the exact |
||
4412 | * opposite effect of that intended. |
||
4413 | */ |
||
4414 | { |
||
4415 | png_bytep temp = png_ptr->big_row_buf + 32; |
||
4416 | int extra = (int)((temp - (png_bytep)0) & 0x0f); |
||
4417 | png_ptr->row_buf = temp - extra - 1/*filter byte*/; |
||
4418 | |||
4419 | |||
4420 | extra = (int)((temp - (png_bytep)0) & 0x0f); |
||
4421 | png_ptr->prev_row = temp - extra - 1/*filter byte*/; |
||
4422 | } |
||
4423 | |||
4424 | |||
4425 | /* Use 31 bytes of padding before and 17 bytes after row_buf. */ |
||
4426 | png_ptr->row_buf = png_ptr->big_row_buf + 31; |
||
4427 | png_ptr->prev_row = png_ptr->big_prev_row + 31; |
||
4428 | #endif |
||
4429 | png_ptr->old_big_row_buf_size = row_bytes + 48; |
||
4430 | } |
||
4431 | |||
4432 | |||
4433 | if (png_ptr->rowbytes > 65535) |
||
4434 | png_error(png_ptr, "This image requires a row greater than 64KB"); |
||
4435 | |||
4436 | |||
4437 | if (png_ptr->rowbytes > (PNG_SIZE_MAX - 1)) |
||
4438 | png_error(png_ptr, "Row has too many bytes to allocate in memory"); |
||
4439 | |||
4440 | |||
4441 | |||
4442 | |||
4443 | png_debug1(3, "height = %u,", png_ptr->height); |
||
4444 | png_debug1(3, "iwidth = %u,", png_ptr->iwidth); |
||
4445 | png_debug1(3, "num_rows = %u,", png_ptr->num_rows); |
||
4446 | png_debug1(3, "rowbytes = %lu,", (unsigned long)png_ptr->rowbytes); |
||
4447 | png_debug1(3, "irowbytes = %lu", |
||
4448 | (unsigned long)PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1); |
||
4449 | |||
4450 | |||
4451 | * does not, so free the read buffer now regardless; the sequential reader |
||
4452 | * reallocates it on demand. |
||
4453 | */ |
||
4454 | if (png_ptr->read_buffer) |
||
4455 | { |
||
4456 | png_bytep buffer = png_ptr->read_buffer; |
||
4457 | |||
4458 | |||
4459 | png_ptr->read_buffer = NULL; |
||
4460 | png_free(png_ptr, buffer); |
||
4461 | } |
||
4462 | |||
4463 | |||
4464 | * value from the stream (note that this will result in a fatal error if the |
||
4465 | * IDAT stream has a bogus deflate header window_bits value, but this should |
||
4466 | * not be happening any longer!) |
||
4467 | */ |
||
4468 | if (png_inflate_claim(png_ptr, png_IDAT) != Z_OK) |
||
4469 | png_error(png_ptr, png_ptr->zstream.msg); |
||
4470 | |||
4471 | |||
4472 | } |
||
4473 | #endif /* PNG_READ_SUPPORTED */=>=>=>=>>>>>>>>>>>>>>>>>>>>>>>>>>><>>>><>><>><>><>><>>>><>><>><>><>><>>>>=>=>=>=>=>>=>=>=>((6-pass)><((6-pass)>=>><>24;><24;>4>4>(s)) |
||
4474 | #><(s)) |