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1 |
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2 /* pngread.c - read a PNG file |
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3 * |
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4 * Last changed in libpng 1.2.37 [June 4, 2009] |
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5 * Copyright (c) 1998-2009 Glenn Randers-Pehrson |
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6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
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7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
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8 * |
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9 * This code is released under the libpng license. |
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10 * For conditions of distribution and use, see the disclaimer |
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11 * and license in png.h |
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12 * |
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13 * This file contains routines that an application calls directly to |
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14 * read a PNG file or stream. |
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15 */ |
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16 |
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17 #define PNG_INTERNAL |
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18 #include "png.h" |
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19 #if defined(PNG_READ_SUPPORTED) |
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20 |
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21 /* Create a PNG structure for reading, and allocate any memory needed. */ |
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22 png_structp PNGAPI |
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23 png_create_read_struct(png_const_charp user_png_ver, png_voidp error_ptr, |
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24 png_error_ptr error_fn, png_error_ptr warn_fn) |
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25 { |
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26 |
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27 #ifdef PNG_USER_MEM_SUPPORTED |
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28 return (png_create_read_struct_2(user_png_ver, error_ptr, error_fn, |
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29 warn_fn, png_voidp_NULL, png_malloc_ptr_NULL, png_free_ptr_NULL)); |
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30 } |
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31 |
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32 /* Alternate create PNG structure for reading, and allocate any memory needed. */ |
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33 png_structp PNGAPI |
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34 png_create_read_struct_2(png_const_charp user_png_ver, png_voidp error_ptr, |
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35 png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, |
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36 png_malloc_ptr malloc_fn, png_free_ptr free_fn) |
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37 { |
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38 #endif /* PNG_USER_MEM_SUPPORTED */ |
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39 |
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40 #ifdef PNG_SETJMP_SUPPORTED |
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41 volatile |
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42 #endif |
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43 png_structp png_ptr; |
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44 |
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45 #ifdef PNG_SETJMP_SUPPORTED |
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46 #ifdef USE_FAR_KEYWORD |
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47 jmp_buf jmpbuf; |
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48 #endif |
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49 #endif |
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50 |
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51 int i; |
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52 |
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53 png_debug(1, "in png_create_read_struct"); |
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54 #ifdef PNG_USER_MEM_SUPPORTED |
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55 png_ptr = (png_structp)png_create_struct_2(PNG_STRUCT_PNG, |
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56 (png_malloc_ptr)malloc_fn, (png_voidp)mem_ptr); |
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57 #else |
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58 png_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); |
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59 #endif |
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60 if (png_ptr == NULL) |
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61 return (NULL); |
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62 |
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63 /* Added at libpng-1.2.6 */ |
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64 #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
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65 png_ptr->user_width_max=PNG_USER_WIDTH_MAX; |
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66 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; |
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67 #endif |
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68 |
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69 #ifdef PNG_SETJMP_SUPPORTED |
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70 #ifdef USE_FAR_KEYWORD |
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71 if (setjmp(jmpbuf)) |
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72 #else |
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73 if (setjmp(png_ptr->jmpbuf)) |
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74 #endif |
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75 { |
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76 png_free(png_ptr, png_ptr->zbuf); |
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77 png_ptr->zbuf = NULL; |
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78 #ifdef PNG_USER_MEM_SUPPORTED |
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79 png_destroy_struct_2((png_voidp)png_ptr, |
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80 (png_free_ptr)free_fn, (png_voidp)mem_ptr); |
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81 #else |
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82 png_destroy_struct((png_voidp)png_ptr); |
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83 #endif |
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84 return (NULL); |
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85 } |
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86 #ifdef USE_FAR_KEYWORD |
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87 png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf)); |
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88 #endif |
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89 #endif |
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90 |
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91 #ifdef PNG_USER_MEM_SUPPORTED |
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92 png_set_mem_fn(png_ptr, mem_ptr, malloc_fn, free_fn); |
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93 #endif |
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94 |
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95 png_set_error_fn(png_ptr, error_ptr, error_fn, warn_fn); |
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96 |
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97 if (user_png_ver) |
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98 { |
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99 i = 0; |
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100 do |
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101 { |
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102 if (user_png_ver[i] != png_libpng_ver[i]) |
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103 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
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104 } while (png_libpng_ver[i++]); |
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105 } |
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106 else |
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107 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
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108 |
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109 |
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110 if (png_ptr->flags & PNG_FLAG_LIBRARY_MISMATCH) |
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111 { |
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112 /* Libpng 0.90 and later are binary incompatible with libpng 0.89, so |
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113 * we must recompile any applications that use any older library version. |
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114 * For versions after libpng 1.0, we will be compatible, so we need |
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115 * only check the first digit. |
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116 */ |
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117 if (user_png_ver == NULL || user_png_ver[0] != png_libpng_ver[0] || |
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118 (user_png_ver[0] == '1' && user_png_ver[2] != png_libpng_ver[2]) || |
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119 (user_png_ver[0] == '0' && user_png_ver[2] < '9')) |
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120 { |
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121 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
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122 char msg[80]; |
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123 if (user_png_ver) |
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124 { |
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125 png_snprintf(msg, 80, |
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126 "Application was compiled with png.h from libpng-%.20s", |
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127 user_png_ver); |
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128 png_warning(png_ptr, msg); |
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129 } |
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130 png_snprintf(msg, 80, |
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131 "Application is running with png.c from libpng-%.20s", |
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132 png_libpng_ver); |
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133 png_warning(png_ptr, msg); |
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134 #endif |
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135 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
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136 png_ptr->flags = 0; |
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137 #endif |
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138 png_error(png_ptr, |
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139 "Incompatible libpng version in application and library"); |
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140 } |
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141 } |
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142 |
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143 /* Initialize zbuf - compression buffer */ |
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144 png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
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145 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
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146 (png_uint_32)png_ptr->zbuf_size); |
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147 png_ptr->zstream.zalloc = png_zalloc; |
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148 png_ptr->zstream.zfree = png_zfree; |
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149 png_ptr->zstream.opaque = (voidpf)png_ptr; |
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150 |
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151 switch (inflateInit(&png_ptr->zstream)) |
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152 { |
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153 case Z_OK: /* Do nothing */ break; |
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154 case Z_MEM_ERROR: |
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155 case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory error"); break; |
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156 case Z_VERSION_ERROR: png_error(png_ptr, "zlib version error"); break; |
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157 default: png_error(png_ptr, "Unknown zlib error"); |
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158 } |
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159 |
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160 png_ptr->zstream.next_out = png_ptr->zbuf; |
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161 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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162 |
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163 png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); |
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164 |
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165 #ifdef PNG_SETJMP_SUPPORTED |
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166 /* Applications that neglect to set up their own setjmp() and then encounter |
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167 a png_error() will longjmp here. Since the jmpbuf is then meaningless we |
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168 abort instead of returning. */ |
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169 #ifdef USE_FAR_KEYWORD |
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170 if (setjmp(jmpbuf)) |
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171 PNG_ABORT(); |
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172 png_memcpy(png_ptr->jmpbuf, jmpbuf, png_sizeof(jmp_buf)); |
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173 #else |
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174 if (setjmp(png_ptr->jmpbuf)) |
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175 PNG_ABORT(); |
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176 #endif |
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177 #endif |
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178 return (png_ptr); |
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179 } |
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180 |
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181 #if defined(PNG_1_0_X) || defined(PNG_1_2_X) |
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182 /* Initialize PNG structure for reading, and allocate any memory needed. |
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183 This interface is deprecated in favour of the png_create_read_struct(), |
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184 and it will disappear as of libpng-1.3.0. */ |
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185 #undef png_read_init |
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186 void PNGAPI |
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187 png_read_init(png_structp png_ptr) |
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188 { |
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189 /* We only come here via pre-1.0.7-compiled applications */ |
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190 png_read_init_2(png_ptr, "1.0.6 or earlier", 0, 0); |
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191 } |
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192 |
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193 void PNGAPI |
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194 png_read_init_2(png_structp png_ptr, png_const_charp user_png_ver, |
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195 png_size_t png_struct_size, png_size_t png_info_size) |
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196 { |
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197 /* We only come here via pre-1.0.12-compiled applications */ |
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198 if (png_ptr == NULL) |
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199 return; |
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200 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
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201 if (png_sizeof(png_struct) > png_struct_size || |
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202 png_sizeof(png_info) > png_info_size) |
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203 { |
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204 char msg[80]; |
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205 png_ptr->warning_fn = NULL; |
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206 if (user_png_ver) |
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207 { |
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208 png_snprintf(msg, 80, |
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209 "Application was compiled with png.h from libpng-%.20s", |
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210 user_png_ver); |
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211 png_warning(png_ptr, msg); |
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212 } |
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213 png_snprintf(msg, 80, |
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214 "Application is running with png.c from libpng-%.20s", |
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215 png_libpng_ver); |
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216 png_warning(png_ptr, msg); |
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217 } |
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218 #endif |
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219 if (png_sizeof(png_struct) > png_struct_size) |
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220 { |
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221 png_ptr->error_fn = NULL; |
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222 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
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223 png_ptr->flags = 0; |
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224 #endif |
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225 png_error(png_ptr, |
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226 "The png struct allocated by the application for reading is too small."); |
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227 } |
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228 if (png_sizeof(png_info) > png_info_size) |
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229 { |
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230 png_ptr->error_fn = NULL; |
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231 #ifdef PNG_ERROR_NUMBERS_SUPPORTED |
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232 png_ptr->flags = 0; |
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233 #endif |
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234 png_error(png_ptr, |
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235 "The info struct allocated by application for reading is too small."); |
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236 } |
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237 png_read_init_3(&png_ptr, user_png_ver, png_struct_size); |
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238 } |
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239 #endif /* PNG_1_0_X || PNG_1_2_X */ |
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240 |
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241 void PNGAPI |
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242 png_read_init_3(png_structpp ptr_ptr, png_const_charp user_png_ver, |
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243 png_size_t png_struct_size) |
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244 { |
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245 #ifdef PNG_SETJMP_SUPPORTED |
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246 jmp_buf tmp_jmp; /* to save current jump buffer */ |
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247 #endif |
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248 |
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249 int i = 0; |
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250 |
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251 png_structp png_ptr=*ptr_ptr; |
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252 |
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253 if (png_ptr == NULL) |
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254 return; |
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255 |
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256 do |
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257 { |
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258 if (user_png_ver[i] != png_libpng_ver[i]) |
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259 { |
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260 #ifdef PNG_LEGACY_SUPPORTED |
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261 png_ptr->flags |= PNG_FLAG_LIBRARY_MISMATCH; |
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262 #else |
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263 png_ptr->warning_fn = NULL; |
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264 png_warning(png_ptr, |
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265 "Application uses deprecated png_read_init() and should be recompiled."); |
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266 break; |
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267 #endif |
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268 } |
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269 } while (png_libpng_ver[i++]); |
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270 |
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271 png_debug(1, "in png_read_init_3"); |
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272 |
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273 #ifdef PNG_SETJMP_SUPPORTED |
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274 /* Save jump buffer and error functions */ |
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275 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf)); |
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276 #endif |
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277 |
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278 if (png_sizeof(png_struct) > png_struct_size) |
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279 { |
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280 png_destroy_struct(png_ptr); |
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281 *ptr_ptr = (png_structp)png_create_struct(PNG_STRUCT_PNG); |
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282 png_ptr = *ptr_ptr; |
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283 } |
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284 |
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285 /* Reset all variables to 0 */ |
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286 png_memset(png_ptr, 0, png_sizeof(png_struct)); |
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287 |
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288 #ifdef PNG_SETJMP_SUPPORTED |
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289 /* Restore jump buffer */ |
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290 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); |
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291 #endif |
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292 |
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293 /* Added at libpng-1.2.6 */ |
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294 #ifdef PNG_SET_USER_LIMITS_SUPPORTED |
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295 png_ptr->user_width_max=PNG_USER_WIDTH_MAX; |
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296 png_ptr->user_height_max=PNG_USER_HEIGHT_MAX; |
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297 #endif |
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298 |
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299 /* Initialize zbuf - compression buffer */ |
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300 png_ptr->zbuf_size = PNG_ZBUF_SIZE; |
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301 png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, |
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302 (png_uint_32)png_ptr->zbuf_size); |
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303 png_ptr->zstream.zalloc = png_zalloc; |
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304 png_ptr->zstream.zfree = png_zfree; |
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305 png_ptr->zstream.opaque = (voidpf)png_ptr; |
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306 |
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307 switch (inflateInit(&png_ptr->zstream)) |
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308 { |
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309 case Z_OK: /* Do nothing */ break; |
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310 case Z_MEM_ERROR: |
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311 case Z_STREAM_ERROR: png_error(png_ptr, "zlib memory"); break; |
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312 case Z_VERSION_ERROR: png_error(png_ptr, "zlib version"); break; |
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313 default: png_error(png_ptr, "Unknown zlib error"); |
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314 } |
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315 |
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316 png_ptr->zstream.next_out = png_ptr->zbuf; |
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317 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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318 |
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319 png_set_read_fn(png_ptr, png_voidp_NULL, png_rw_ptr_NULL); |
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320 } |
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321 |
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322 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
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323 /* Read the information before the actual image data. This has been |
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324 * changed in v0.90 to allow reading a file that already has the magic |
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325 * bytes read from the stream. You can tell libpng how many bytes have |
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326 * been read from the beginning of the stream (up to the maximum of 8) |
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327 * via png_set_sig_bytes(), and we will only check the remaining bytes |
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328 * here. The application can then have access to the signature bytes we |
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329 * read if it is determined that this isn't a valid PNG file. |
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330 */ |
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331 void PNGAPI |
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332 png_read_info(png_structp png_ptr, png_infop info_ptr) |
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333 { |
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334 if (png_ptr == NULL || info_ptr == NULL) |
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335 return; |
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336 png_debug(1, "in png_read_info"); |
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337 /* If we haven't checked all of the PNG signature bytes, do so now. */ |
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338 if (png_ptr->sig_bytes < 8) |
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339 { |
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340 png_size_t num_checked = png_ptr->sig_bytes, |
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341 num_to_check = 8 - num_checked; |
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342 |
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343 png_read_data(png_ptr, &(info_ptr->signature[num_checked]), num_to_check); |
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344 png_ptr->sig_bytes = 8; |
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345 |
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346 if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check)) |
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347 { |
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348 if (num_checked < 4 && |
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349 png_sig_cmp(info_ptr->signature, num_checked, num_to_check - 4)) |
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350 png_error(png_ptr, "Not a PNG file"); |
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351 else |
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352 png_error(png_ptr, "PNG file corrupted by ASCII conversion"); |
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353 } |
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354 if (num_checked < 3) |
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355 png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE; |
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356 } |
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357 |
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358 for (;;) |
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359 { |
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360 #ifdef PNG_USE_LOCAL_ARRAYS |
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361 PNG_CONST PNG_IHDR; |
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362 PNG_CONST PNG_IDAT; |
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363 PNG_CONST PNG_IEND; |
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364 PNG_CONST PNG_PLTE; |
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365 #if defined(PNG_READ_bKGD_SUPPORTED) |
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366 PNG_CONST PNG_bKGD; |
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367 #endif |
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368 #if defined(PNG_READ_cHRM_SUPPORTED) |
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369 PNG_CONST PNG_cHRM; |
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370 #endif |
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371 #if defined(PNG_READ_gAMA_SUPPORTED) |
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372 PNG_CONST PNG_gAMA; |
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373 #endif |
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374 #if defined(PNG_READ_hIST_SUPPORTED) |
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375 PNG_CONST PNG_hIST; |
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376 #endif |
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377 #if defined(PNG_READ_iCCP_SUPPORTED) |
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378 PNG_CONST PNG_iCCP; |
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379 #endif |
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380 #if defined(PNG_READ_iTXt_SUPPORTED) |
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381 PNG_CONST PNG_iTXt; |
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382 #endif |
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383 #if defined(PNG_READ_oFFs_SUPPORTED) |
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384 PNG_CONST PNG_oFFs; |
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385 #endif |
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386 #if defined(PNG_READ_pCAL_SUPPORTED) |
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387 PNG_CONST PNG_pCAL; |
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388 #endif |
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389 #if defined(PNG_READ_pHYs_SUPPORTED) |
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390 PNG_CONST PNG_pHYs; |
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391 #endif |
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392 #if defined(PNG_READ_sBIT_SUPPORTED) |
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393 PNG_CONST PNG_sBIT; |
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394 #endif |
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395 #if defined(PNG_READ_sCAL_SUPPORTED) |
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396 PNG_CONST PNG_sCAL; |
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397 #endif |
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398 #if defined(PNG_READ_sPLT_SUPPORTED) |
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399 PNG_CONST PNG_sPLT; |
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400 #endif |
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401 #if defined(PNG_READ_sRGB_SUPPORTED) |
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402 PNG_CONST PNG_sRGB; |
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403 #endif |
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404 #if defined(PNG_READ_tEXt_SUPPORTED) |
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405 PNG_CONST PNG_tEXt; |
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406 #endif |
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407 #if defined(PNG_READ_tIME_SUPPORTED) |
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408 PNG_CONST PNG_tIME; |
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409 #endif |
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410 #if defined(PNG_READ_tRNS_SUPPORTED) |
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411 PNG_CONST PNG_tRNS; |
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412 #endif |
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413 #if defined(PNG_READ_zTXt_SUPPORTED) |
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414 PNG_CONST PNG_zTXt; |
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415 #endif |
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416 #endif /* PNG_USE_LOCAL_ARRAYS */ |
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417 png_uint_32 length = png_read_chunk_header(png_ptr); |
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418 PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; |
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419 |
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420 /* This should be a binary subdivision search or a hash for |
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421 * matching the chunk name rather than a linear search. |
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422 */ |
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423 if (!png_memcmp(chunk_name, png_IDAT, 4)) |
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424 if (png_ptr->mode & PNG_AFTER_IDAT) |
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425 png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT; |
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426 |
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427 if (!png_memcmp(chunk_name, png_IHDR, 4)) |
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428 png_handle_IHDR(png_ptr, info_ptr, length); |
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429 else if (!png_memcmp(chunk_name, png_IEND, 4)) |
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430 png_handle_IEND(png_ptr, info_ptr, length); |
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431 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
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432 else if (png_handle_as_unknown(png_ptr, chunk_name)) |
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433 { |
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434 if (!png_memcmp(chunk_name, png_IDAT, 4)) |
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435 png_ptr->mode |= PNG_HAVE_IDAT; |
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436 png_handle_unknown(png_ptr, info_ptr, length); |
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437 if (!png_memcmp(chunk_name, png_PLTE, 4)) |
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438 png_ptr->mode |= PNG_HAVE_PLTE; |
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439 else if (!png_memcmp(chunk_name, png_IDAT, 4)) |
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440 { |
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441 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
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442 png_error(png_ptr, "Missing IHDR before IDAT"); |
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443 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
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444 !(png_ptr->mode & PNG_HAVE_PLTE)) |
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445 png_error(png_ptr, "Missing PLTE before IDAT"); |
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446 break; |
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447 } |
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448 } |
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449 #endif |
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450 else if (!png_memcmp(chunk_name, png_PLTE, 4)) |
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451 png_handle_PLTE(png_ptr, info_ptr, length); |
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452 else if (!png_memcmp(chunk_name, png_IDAT, 4)) |
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453 { |
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454 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
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455 png_error(png_ptr, "Missing IHDR before IDAT"); |
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456 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
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457 !(png_ptr->mode & PNG_HAVE_PLTE)) |
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458 png_error(png_ptr, "Missing PLTE before IDAT"); |
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459 |
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460 png_ptr->idat_size = length; |
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461 png_ptr->mode |= PNG_HAVE_IDAT; |
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462 break; |
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463 } |
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464 #if defined(PNG_READ_bKGD_SUPPORTED) |
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465 else if (!png_memcmp(chunk_name, png_bKGD, 4)) |
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466 png_handle_bKGD(png_ptr, info_ptr, length); |
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467 #endif |
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468 #if defined(PNG_READ_cHRM_SUPPORTED) |
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469 else if (!png_memcmp(chunk_name, png_cHRM, 4)) |
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470 png_handle_cHRM(png_ptr, info_ptr, length); |
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471 #endif |
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472 #if defined(PNG_READ_gAMA_SUPPORTED) |
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473 else if (!png_memcmp(chunk_name, png_gAMA, 4)) |
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474 png_handle_gAMA(png_ptr, info_ptr, length); |
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475 #endif |
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476 #if defined(PNG_READ_hIST_SUPPORTED) |
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477 else if (!png_memcmp(chunk_name, png_hIST, 4)) |
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478 png_handle_hIST(png_ptr, info_ptr, length); |
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479 #endif |
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480 #if defined(PNG_READ_oFFs_SUPPORTED) |
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481 else if (!png_memcmp(chunk_name, png_oFFs, 4)) |
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482 png_handle_oFFs(png_ptr, info_ptr, length); |
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483 #endif |
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484 #if defined(PNG_READ_pCAL_SUPPORTED) |
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485 else if (!png_memcmp(chunk_name, png_pCAL, 4)) |
|
486 png_handle_pCAL(png_ptr, info_ptr, length); |
|
487 #endif |
|
488 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
489 else if (!png_memcmp(chunk_name, png_sCAL, 4)) |
|
490 png_handle_sCAL(png_ptr, info_ptr, length); |
|
491 #endif |
|
492 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
493 else if (!png_memcmp(chunk_name, png_pHYs, 4)) |
|
494 png_handle_pHYs(png_ptr, info_ptr, length); |
|
495 #endif |
|
496 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
497 else if (!png_memcmp(chunk_name, png_sBIT, 4)) |
|
498 png_handle_sBIT(png_ptr, info_ptr, length); |
|
499 #endif |
|
500 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
501 else if (!png_memcmp(chunk_name, png_sRGB, 4)) |
|
502 png_handle_sRGB(png_ptr, info_ptr, length); |
|
503 #endif |
|
504 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
505 else if (!png_memcmp(chunk_name, png_iCCP, 4)) |
|
506 png_handle_iCCP(png_ptr, info_ptr, length); |
|
507 #endif |
|
508 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
509 else if (!png_memcmp(chunk_name, png_sPLT, 4)) |
|
510 png_handle_sPLT(png_ptr, info_ptr, length); |
|
511 #endif |
|
512 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
513 else if (!png_memcmp(chunk_name, png_tEXt, 4)) |
|
514 png_handle_tEXt(png_ptr, info_ptr, length); |
|
515 #endif |
|
516 #if defined(PNG_READ_tIME_SUPPORTED) |
|
517 else if (!png_memcmp(chunk_name, png_tIME, 4)) |
|
518 png_handle_tIME(png_ptr, info_ptr, length); |
|
519 #endif |
|
520 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
521 else if (!png_memcmp(chunk_name, png_tRNS, 4)) |
|
522 png_handle_tRNS(png_ptr, info_ptr, length); |
|
523 #endif |
|
524 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
525 else if (!png_memcmp(chunk_name, png_zTXt, 4)) |
|
526 png_handle_zTXt(png_ptr, info_ptr, length); |
|
527 #endif |
|
528 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
529 else if (!png_memcmp(chunk_name, png_iTXt, 4)) |
|
530 png_handle_iTXt(png_ptr, info_ptr, length); |
|
531 #endif |
|
532 else |
|
533 png_handle_unknown(png_ptr, info_ptr, length); |
|
534 } |
|
535 } |
|
536 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
537 |
|
538 /* Optional call to update the users info_ptr structure */ |
|
539 void PNGAPI |
|
540 png_read_update_info(png_structp png_ptr, png_infop info_ptr) |
|
541 { |
|
542 png_debug(1, "in png_read_update_info"); |
|
543 if (png_ptr == NULL) |
|
544 return; |
|
545 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
|
546 png_read_start_row(png_ptr); |
|
547 else |
|
548 png_warning(png_ptr, |
|
549 "Ignoring extra png_read_update_info() call; row buffer not reallocated"); |
|
550 png_read_transform_info(png_ptr, info_ptr); |
|
551 } |
|
552 |
|
553 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
554 /* Initialize palette, background, etc, after transformations |
|
555 * are set, but before any reading takes place. This allows |
|
556 * the user to obtain a gamma-corrected palette, for example. |
|
557 * If the user doesn't call this, we will do it ourselves. |
|
558 */ |
|
559 void PNGAPI |
|
560 png_start_read_image(png_structp png_ptr) |
|
561 { |
|
562 png_debug(1, "in png_start_read_image"); |
|
563 if (png_ptr == NULL) |
|
564 return; |
|
565 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
|
566 png_read_start_row(png_ptr); |
|
567 } |
|
568 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
569 |
|
570 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
571 void PNGAPI |
|
572 png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row) |
|
573 { |
|
574 #ifdef PNG_USE_LOCAL_ARRAYS |
|
575 PNG_CONST PNG_IDAT; |
|
576 PNG_CONST int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, |
|
577 0xff}; |
|
578 PNG_CONST int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff}; |
|
579 #endif |
|
580 int ret; |
|
581 if (png_ptr == NULL) |
|
582 return; |
|
583 png_debug2(1, "in png_read_row (row %lu, pass %d)", |
|
584 png_ptr->row_number, png_ptr->pass); |
|
585 if (!(png_ptr->flags & PNG_FLAG_ROW_INIT)) |
|
586 png_read_start_row(png_ptr); |
|
587 if (png_ptr->row_number == 0 && png_ptr->pass == 0) |
|
588 { |
|
589 /* Check for transforms that have been set but were defined out */ |
|
590 #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED) |
|
591 if (png_ptr->transformations & PNG_INVERT_MONO) |
|
592 png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined."); |
|
593 #endif |
|
594 #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED) |
|
595 if (png_ptr->transformations & PNG_FILLER) |
|
596 png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined."); |
|
597 #endif |
|
598 #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && !defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
599 if (png_ptr->transformations & PNG_PACKSWAP) |
|
600 png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined."); |
|
601 #endif |
|
602 #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED) |
|
603 if (png_ptr->transformations & PNG_PACK) |
|
604 png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined."); |
|
605 #endif |
|
606 #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED) |
|
607 if (png_ptr->transformations & PNG_SHIFT) |
|
608 png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined."); |
|
609 #endif |
|
610 #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED) |
|
611 if (png_ptr->transformations & PNG_BGR) |
|
612 png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined."); |
|
613 #endif |
|
614 #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED) |
|
615 if (png_ptr->transformations & PNG_SWAP_BYTES) |
|
616 png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined."); |
|
617 #endif |
|
618 } |
|
619 |
|
620 #if defined(PNG_READ_INTERLACING_SUPPORTED) |
|
621 /* If interlaced and we do not need a new row, combine row and return */ |
|
622 if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE)) |
|
623 { |
|
624 switch (png_ptr->pass) |
|
625 { |
|
626 case 0: |
|
627 if (png_ptr->row_number & 0x07) |
|
628 { |
|
629 if (dsp_row != NULL) |
|
630 png_combine_row(png_ptr, dsp_row, |
|
631 png_pass_dsp_mask[png_ptr->pass]); |
|
632 png_read_finish_row(png_ptr); |
|
633 return; |
|
634 } |
|
635 break; |
|
636 case 1: |
|
637 if ((png_ptr->row_number & 0x07) || png_ptr->width < 5) |
|
638 { |
|
639 if (dsp_row != NULL) |
|
640 png_combine_row(png_ptr, dsp_row, |
|
641 png_pass_dsp_mask[png_ptr->pass]); |
|
642 png_read_finish_row(png_ptr); |
|
643 return; |
|
644 } |
|
645 break; |
|
646 case 2: |
|
647 if ((png_ptr->row_number & 0x07) != 4) |
|
648 { |
|
649 if (dsp_row != NULL && (png_ptr->row_number & 4)) |
|
650 png_combine_row(png_ptr, dsp_row, |
|
651 png_pass_dsp_mask[png_ptr->pass]); |
|
652 png_read_finish_row(png_ptr); |
|
653 return; |
|
654 } |
|
655 break; |
|
656 case 3: |
|
657 if ((png_ptr->row_number & 3) || png_ptr->width < 3) |
|
658 { |
|
659 if (dsp_row != NULL) |
|
660 png_combine_row(png_ptr, dsp_row, |
|
661 png_pass_dsp_mask[png_ptr->pass]); |
|
662 png_read_finish_row(png_ptr); |
|
663 return; |
|
664 } |
|
665 break; |
|
666 case 4: |
|
667 if ((png_ptr->row_number & 3) != 2) |
|
668 { |
|
669 if (dsp_row != NULL && (png_ptr->row_number & 2)) |
|
670 png_combine_row(png_ptr, dsp_row, |
|
671 png_pass_dsp_mask[png_ptr->pass]); |
|
672 png_read_finish_row(png_ptr); |
|
673 return; |
|
674 } |
|
675 break; |
|
676 case 5: |
|
677 if ((png_ptr->row_number & 1) || png_ptr->width < 2) |
|
678 { |
|
679 if (dsp_row != NULL) |
|
680 png_combine_row(png_ptr, dsp_row, |
|
681 png_pass_dsp_mask[png_ptr->pass]); |
|
682 png_read_finish_row(png_ptr); |
|
683 return; |
|
684 } |
|
685 break; |
|
686 case 6: |
|
687 if (!(png_ptr->row_number & 1)) |
|
688 { |
|
689 png_read_finish_row(png_ptr); |
|
690 return; |
|
691 } |
|
692 break; |
|
693 } |
|
694 } |
|
695 #endif |
|
696 |
|
697 if (!(png_ptr->mode & PNG_HAVE_IDAT)) |
|
698 png_error(png_ptr, "Invalid attempt to read row data"); |
|
699 |
|
700 png_ptr->zstream.next_out = png_ptr->row_buf; |
|
701 png_ptr->zstream.avail_out = (uInt)png_ptr->irowbytes; |
|
702 do |
|
703 { |
|
704 if (!(png_ptr->zstream.avail_in)) |
|
705 { |
|
706 while (!png_ptr->idat_size) |
|
707 { |
|
708 png_crc_finish(png_ptr, 0); |
|
709 |
|
710 png_ptr->idat_size = png_read_chunk_header(png_ptr); |
|
711 if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
|
712 png_error(png_ptr, "Not enough image data"); |
|
713 } |
|
714 png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; |
|
715 png_ptr->zstream.next_in = png_ptr->zbuf; |
|
716 if (png_ptr->zbuf_size > png_ptr->idat_size) |
|
717 png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; |
|
718 png_crc_read(png_ptr, png_ptr->zbuf, |
|
719 (png_size_t)png_ptr->zstream.avail_in); |
|
720 png_ptr->idat_size -= png_ptr->zstream.avail_in; |
|
721 } |
|
722 ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); |
|
723 if (ret == Z_STREAM_END) |
|
724 { |
|
725 if (png_ptr->zstream.avail_out || png_ptr->zstream.avail_in || |
|
726 png_ptr->idat_size) |
|
727 png_error(png_ptr, "Extra compressed data"); |
|
728 png_ptr->mode |= PNG_AFTER_IDAT; |
|
729 png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; |
|
730 break; |
|
731 } |
|
732 if (ret != Z_OK) |
|
733 png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : |
|
734 "Decompression error"); |
|
735 |
|
736 } while (png_ptr->zstream.avail_out); |
|
737 |
|
738 png_ptr->row_info.color_type = png_ptr->color_type; |
|
739 png_ptr->row_info.width = png_ptr->iwidth; |
|
740 png_ptr->row_info.channels = png_ptr->channels; |
|
741 png_ptr->row_info.bit_depth = png_ptr->bit_depth; |
|
742 png_ptr->row_info.pixel_depth = png_ptr->pixel_depth; |
|
743 png_ptr->row_info.rowbytes = PNG_ROWBYTES(png_ptr->row_info.pixel_depth, |
|
744 png_ptr->row_info.width); |
|
745 |
|
746 if (png_ptr->row_buf[0]) |
|
747 png_read_filter_row(png_ptr, &(png_ptr->row_info), |
|
748 png_ptr->row_buf + 1, png_ptr->prev_row + 1, |
|
749 (int)(png_ptr->row_buf[0])); |
|
750 |
|
751 png_memcpy_check(png_ptr, png_ptr->prev_row, png_ptr->row_buf, |
|
752 png_ptr->rowbytes + 1); |
|
753 |
|
754 #if defined(PNG_MNG_FEATURES_SUPPORTED) |
|
755 if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) && |
|
756 (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING)) |
|
757 { |
|
758 /* Intrapixel differencing */ |
|
759 png_do_read_intrapixel(&(png_ptr->row_info), png_ptr->row_buf + 1); |
|
760 } |
|
761 #endif |
|
762 |
|
763 |
|
764 if (png_ptr->transformations || (png_ptr->flags&PNG_FLAG_STRIP_ALPHA)) |
|
765 png_do_read_transformations(png_ptr); |
|
766 |
|
767 #if defined(PNG_READ_INTERLACING_SUPPORTED) |
|
768 /* Blow up interlaced rows to full size */ |
|
769 if (png_ptr->interlaced && |
|
770 (png_ptr->transformations & PNG_INTERLACE)) |
|
771 { |
|
772 if (png_ptr->pass < 6) |
|
773 /* Old interface (pre-1.0.9): |
|
774 * png_do_read_interlace(&(png_ptr->row_info), |
|
775 * png_ptr->row_buf + 1, png_ptr->pass, png_ptr->transformations); |
|
776 */ |
|
777 png_do_read_interlace(png_ptr); |
|
778 |
|
779 if (dsp_row != NULL) |
|
780 png_combine_row(png_ptr, dsp_row, |
|
781 png_pass_dsp_mask[png_ptr->pass]); |
|
782 if (row != NULL) |
|
783 png_combine_row(png_ptr, row, |
|
784 png_pass_mask[png_ptr->pass]); |
|
785 } |
|
786 else |
|
787 #endif |
|
788 { |
|
789 if (row != NULL) |
|
790 png_combine_row(png_ptr, row, 0xff); |
|
791 if (dsp_row != NULL) |
|
792 png_combine_row(png_ptr, dsp_row, 0xff); |
|
793 } |
|
794 png_read_finish_row(png_ptr); |
|
795 |
|
796 if (png_ptr->read_row_fn != NULL) |
|
797 (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass); |
|
798 } |
|
799 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
800 |
|
801 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
802 /* Read one or more rows of image data. If the image is interlaced, |
|
803 * and png_set_interlace_handling() has been called, the rows need to |
|
804 * contain the contents of the rows from the previous pass. If the |
|
805 * image has alpha or transparency, and png_handle_alpha()[*] has been |
|
806 * called, the rows contents must be initialized to the contents of the |
|
807 * screen. |
|
808 * |
|
809 * "row" holds the actual image, and pixels are placed in it |
|
810 * as they arrive. If the image is displayed after each pass, it will |
|
811 * appear to "sparkle" in. "display_row" can be used to display a |
|
812 * "chunky" progressive image, with finer detail added as it becomes |
|
813 * available. If you do not want this "chunky" display, you may pass |
|
814 * NULL for display_row. If you do not want the sparkle display, and |
|
815 * you have not called png_handle_alpha(), you may pass NULL for rows. |
|
816 * If you have called png_handle_alpha(), and the image has either an |
|
817 * alpha channel or a transparency chunk, you must provide a buffer for |
|
818 * rows. In this case, you do not have to provide a display_row buffer |
|
819 * also, but you may. If the image is not interlaced, or if you have |
|
820 * not called png_set_interlace_handling(), the display_row buffer will |
|
821 * be ignored, so pass NULL to it. |
|
822 * |
|
823 * [*] png_handle_alpha() does not exist yet, as of this version of libpng |
|
824 */ |
|
825 |
|
826 void PNGAPI |
|
827 png_read_rows(png_structp png_ptr, png_bytepp row, |
|
828 png_bytepp display_row, png_uint_32 num_rows) |
|
829 { |
|
830 png_uint_32 i; |
|
831 png_bytepp rp; |
|
832 png_bytepp dp; |
|
833 |
|
834 png_debug(1, "in png_read_rows"); |
|
835 if (png_ptr == NULL) |
|
836 return; |
|
837 rp = row; |
|
838 dp = display_row; |
|
839 if (rp != NULL && dp != NULL) |
|
840 for (i = 0; i < num_rows; i++) |
|
841 { |
|
842 png_bytep rptr = *rp++; |
|
843 png_bytep dptr = *dp++; |
|
844 |
|
845 png_read_row(png_ptr, rptr, dptr); |
|
846 } |
|
847 else if (rp != NULL) |
|
848 for (i = 0; i < num_rows; i++) |
|
849 { |
|
850 png_bytep rptr = *rp; |
|
851 png_read_row(png_ptr, rptr, png_bytep_NULL); |
|
852 rp++; |
|
853 } |
|
854 else if (dp != NULL) |
|
855 for (i = 0; i < num_rows; i++) |
|
856 { |
|
857 png_bytep dptr = *dp; |
|
858 png_read_row(png_ptr, png_bytep_NULL, dptr); |
|
859 dp++; |
|
860 } |
|
861 } |
|
862 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
863 |
|
864 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
865 /* Read the entire image. If the image has an alpha channel or a tRNS |
|
866 * chunk, and you have called png_handle_alpha()[*], you will need to |
|
867 * initialize the image to the current image that PNG will be overlaying. |
|
868 * We set the num_rows again here, in case it was incorrectly set in |
|
869 * png_read_start_row() by a call to png_read_update_info() or |
|
870 * png_start_read_image() if png_set_interlace_handling() wasn't called |
|
871 * prior to either of these functions like it should have been. You can |
|
872 * only call this function once. If you desire to have an image for |
|
873 * each pass of a interlaced image, use png_read_rows() instead. |
|
874 * |
|
875 * [*] png_handle_alpha() does not exist yet, as of this version of libpng |
|
876 */ |
|
877 void PNGAPI |
|
878 png_read_image(png_structp png_ptr, png_bytepp image) |
|
879 { |
|
880 png_uint_32 i, image_height; |
|
881 int pass, j; |
|
882 png_bytepp rp; |
|
883 |
|
884 png_debug(1, "in png_read_image"); |
|
885 if (png_ptr == NULL) |
|
886 return; |
|
887 |
|
888 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
889 pass = png_set_interlace_handling(png_ptr); |
|
890 #else |
|
891 if (png_ptr->interlaced) |
|
892 png_error(png_ptr, |
|
893 "Cannot read interlaced image -- interlace handler disabled."); |
|
894 pass = 1; |
|
895 #endif |
|
896 |
|
897 |
|
898 image_height=png_ptr->height; |
|
899 png_ptr->num_rows = image_height; /* Make sure this is set correctly */ |
|
900 |
|
901 for (j = 0; j < pass; j++) |
|
902 { |
|
903 rp = image; |
|
904 for (i = 0; i < image_height; i++) |
|
905 { |
|
906 png_read_row(png_ptr, *rp, png_bytep_NULL); |
|
907 rp++; |
|
908 } |
|
909 } |
|
910 } |
|
911 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
912 |
|
913 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
914 /* Read the end of the PNG file. Will not read past the end of the |
|
915 * file, will verify the end is accurate, and will read any comments |
|
916 * or time information at the end of the file, if info is not NULL. |
|
917 */ |
|
918 void PNGAPI |
|
919 png_read_end(png_structp png_ptr, png_infop info_ptr) |
|
920 { |
|
921 png_debug(1, "in png_read_end"); |
|
922 if (png_ptr == NULL) |
|
923 return; |
|
924 png_crc_finish(png_ptr, 0); /* Finish off CRC from last IDAT chunk */ |
|
925 |
|
926 do |
|
927 { |
|
928 #ifdef PNG_USE_LOCAL_ARRAYS |
|
929 PNG_CONST PNG_IHDR; |
|
930 PNG_CONST PNG_IDAT; |
|
931 PNG_CONST PNG_IEND; |
|
932 PNG_CONST PNG_PLTE; |
|
933 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
934 PNG_CONST PNG_bKGD; |
|
935 #endif |
|
936 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
937 PNG_CONST PNG_cHRM; |
|
938 #endif |
|
939 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
940 PNG_CONST PNG_gAMA; |
|
941 #endif |
|
942 #if defined(PNG_READ_hIST_SUPPORTED) |
|
943 PNG_CONST PNG_hIST; |
|
944 #endif |
|
945 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
946 PNG_CONST PNG_iCCP; |
|
947 #endif |
|
948 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
949 PNG_CONST PNG_iTXt; |
|
950 #endif |
|
951 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
952 PNG_CONST PNG_oFFs; |
|
953 #endif |
|
954 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
955 PNG_CONST PNG_pCAL; |
|
956 #endif |
|
957 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
958 PNG_CONST PNG_pHYs; |
|
959 #endif |
|
960 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
961 PNG_CONST PNG_sBIT; |
|
962 #endif |
|
963 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
964 PNG_CONST PNG_sCAL; |
|
965 #endif |
|
966 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
967 PNG_CONST PNG_sPLT; |
|
968 #endif |
|
969 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
970 PNG_CONST PNG_sRGB; |
|
971 #endif |
|
972 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
973 PNG_CONST PNG_tEXt; |
|
974 #endif |
|
975 #if defined(PNG_READ_tIME_SUPPORTED) |
|
976 PNG_CONST PNG_tIME; |
|
977 #endif |
|
978 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
979 PNG_CONST PNG_tRNS; |
|
980 #endif |
|
981 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
982 PNG_CONST PNG_zTXt; |
|
983 #endif |
|
984 #endif /* PNG_USE_LOCAL_ARRAYS */ |
|
985 png_uint_32 length = png_read_chunk_header(png_ptr); |
|
986 PNG_CONST png_bytep chunk_name = png_ptr->chunk_name; |
|
987 |
|
988 if (!png_memcmp(chunk_name, png_IHDR, 4)) |
|
989 png_handle_IHDR(png_ptr, info_ptr, length); |
|
990 else if (!png_memcmp(chunk_name, png_IEND, 4)) |
|
991 png_handle_IEND(png_ptr, info_ptr, length); |
|
992 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
|
993 else if (png_handle_as_unknown(png_ptr, chunk_name)) |
|
994 { |
|
995 if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
996 { |
|
997 if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) |
|
998 png_error(png_ptr, "Too many IDAT's found"); |
|
999 } |
|
1000 png_handle_unknown(png_ptr, info_ptr, length); |
|
1001 if (!png_memcmp(chunk_name, png_PLTE, 4)) |
|
1002 png_ptr->mode |= PNG_HAVE_PLTE; |
|
1003 } |
|
1004 #endif |
|
1005 else if (!png_memcmp(chunk_name, png_IDAT, 4)) |
|
1006 { |
|
1007 /* Zero length IDATs are legal after the last IDAT has been |
|
1008 * read, but not after other chunks have been read. |
|
1009 */ |
|
1010 if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT)) |
|
1011 png_error(png_ptr, "Too many IDAT's found"); |
|
1012 png_crc_finish(png_ptr, length); |
|
1013 } |
|
1014 else if (!png_memcmp(chunk_name, png_PLTE, 4)) |
|
1015 png_handle_PLTE(png_ptr, info_ptr, length); |
|
1016 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
1017 else if (!png_memcmp(chunk_name, png_bKGD, 4)) |
|
1018 png_handle_bKGD(png_ptr, info_ptr, length); |
|
1019 #endif |
|
1020 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
1021 else if (!png_memcmp(chunk_name, png_cHRM, 4)) |
|
1022 png_handle_cHRM(png_ptr, info_ptr, length); |
|
1023 #endif |
|
1024 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
1025 else if (!png_memcmp(chunk_name, png_gAMA, 4)) |
|
1026 png_handle_gAMA(png_ptr, info_ptr, length); |
|
1027 #endif |
|
1028 #if defined(PNG_READ_hIST_SUPPORTED) |
|
1029 else if (!png_memcmp(chunk_name, png_hIST, 4)) |
|
1030 png_handle_hIST(png_ptr, info_ptr, length); |
|
1031 #endif |
|
1032 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
1033 else if (!png_memcmp(chunk_name, png_oFFs, 4)) |
|
1034 png_handle_oFFs(png_ptr, info_ptr, length); |
|
1035 #endif |
|
1036 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
1037 else if (!png_memcmp(chunk_name, png_pCAL, 4)) |
|
1038 png_handle_pCAL(png_ptr, info_ptr, length); |
|
1039 #endif |
|
1040 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
1041 else if (!png_memcmp(chunk_name, png_sCAL, 4)) |
|
1042 png_handle_sCAL(png_ptr, info_ptr, length); |
|
1043 #endif |
|
1044 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
1045 else if (!png_memcmp(chunk_name, png_pHYs, 4)) |
|
1046 png_handle_pHYs(png_ptr, info_ptr, length); |
|
1047 #endif |
|
1048 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
1049 else if (!png_memcmp(chunk_name, png_sBIT, 4)) |
|
1050 png_handle_sBIT(png_ptr, info_ptr, length); |
|
1051 #endif |
|
1052 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
1053 else if (!png_memcmp(chunk_name, png_sRGB, 4)) |
|
1054 png_handle_sRGB(png_ptr, info_ptr, length); |
|
1055 #endif |
|
1056 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
1057 else if (!png_memcmp(chunk_name, png_iCCP, 4)) |
|
1058 png_handle_iCCP(png_ptr, info_ptr, length); |
|
1059 #endif |
|
1060 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
1061 else if (!png_memcmp(chunk_name, png_sPLT, 4)) |
|
1062 png_handle_sPLT(png_ptr, info_ptr, length); |
|
1063 #endif |
|
1064 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
1065 else if (!png_memcmp(chunk_name, png_tEXt, 4)) |
|
1066 png_handle_tEXt(png_ptr, info_ptr, length); |
|
1067 #endif |
|
1068 #if defined(PNG_READ_tIME_SUPPORTED) |
|
1069 else if (!png_memcmp(chunk_name, png_tIME, 4)) |
|
1070 png_handle_tIME(png_ptr, info_ptr, length); |
|
1071 #endif |
|
1072 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
1073 else if (!png_memcmp(chunk_name, png_tRNS, 4)) |
|
1074 png_handle_tRNS(png_ptr, info_ptr, length); |
|
1075 #endif |
|
1076 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
1077 else if (!png_memcmp(chunk_name, png_zTXt, 4)) |
|
1078 png_handle_zTXt(png_ptr, info_ptr, length); |
|
1079 #endif |
|
1080 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
1081 else if (!png_memcmp(chunk_name, png_iTXt, 4)) |
|
1082 png_handle_iTXt(png_ptr, info_ptr, length); |
|
1083 #endif |
|
1084 else |
|
1085 png_handle_unknown(png_ptr, info_ptr, length); |
|
1086 } while (!(png_ptr->mode & PNG_HAVE_IEND)); |
|
1087 } |
|
1088 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
1089 |
|
1090 /* Free all memory used by the read */ |
|
1091 void PNGAPI |
|
1092 png_destroy_read_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr, |
|
1093 png_infopp end_info_ptr_ptr) |
|
1094 { |
|
1095 png_structp png_ptr = NULL; |
|
1096 png_infop info_ptr = NULL, end_info_ptr = NULL; |
|
1097 #ifdef PNG_USER_MEM_SUPPORTED |
|
1098 png_free_ptr free_fn = NULL; |
|
1099 png_voidp mem_ptr = NULL; |
|
1100 #endif |
|
1101 |
|
1102 png_debug(1, "in png_destroy_read_struct"); |
|
1103 if (png_ptr_ptr != NULL) |
|
1104 png_ptr = *png_ptr_ptr; |
|
1105 if (png_ptr == NULL) |
|
1106 return; |
|
1107 |
|
1108 #ifdef PNG_USER_MEM_SUPPORTED |
|
1109 free_fn = png_ptr->free_fn; |
|
1110 mem_ptr = png_ptr->mem_ptr; |
|
1111 #endif |
|
1112 |
|
1113 if (info_ptr_ptr != NULL) |
|
1114 info_ptr = *info_ptr_ptr; |
|
1115 |
|
1116 if (end_info_ptr_ptr != NULL) |
|
1117 end_info_ptr = *end_info_ptr_ptr; |
|
1118 |
|
1119 png_read_destroy(png_ptr, info_ptr, end_info_ptr); |
|
1120 |
|
1121 if (info_ptr != NULL) |
|
1122 { |
|
1123 #if defined(PNG_TEXT_SUPPORTED) |
|
1124 png_free_data(png_ptr, info_ptr, PNG_FREE_TEXT, -1); |
|
1125 #endif |
|
1126 |
|
1127 #ifdef PNG_USER_MEM_SUPPORTED |
|
1128 png_destroy_struct_2((png_voidp)info_ptr, (png_free_ptr)free_fn, |
|
1129 (png_voidp)mem_ptr); |
|
1130 #else |
|
1131 png_destroy_struct((png_voidp)info_ptr); |
|
1132 #endif |
|
1133 *info_ptr_ptr = NULL; |
|
1134 } |
|
1135 |
|
1136 if (end_info_ptr != NULL) |
|
1137 { |
|
1138 #if defined(PNG_READ_TEXT_SUPPORTED) |
|
1139 png_free_data(png_ptr, end_info_ptr, PNG_FREE_TEXT, -1); |
|
1140 #endif |
|
1141 #ifdef PNG_USER_MEM_SUPPORTED |
|
1142 png_destroy_struct_2((png_voidp)end_info_ptr, (png_free_ptr)free_fn, |
|
1143 (png_voidp)mem_ptr); |
|
1144 #else |
|
1145 png_destroy_struct((png_voidp)end_info_ptr); |
|
1146 #endif |
|
1147 *end_info_ptr_ptr = NULL; |
|
1148 } |
|
1149 |
|
1150 if (png_ptr != NULL) |
|
1151 { |
|
1152 #ifdef PNG_USER_MEM_SUPPORTED |
|
1153 png_destroy_struct_2((png_voidp)png_ptr, (png_free_ptr)free_fn, |
|
1154 (png_voidp)mem_ptr); |
|
1155 #else |
|
1156 png_destroy_struct((png_voidp)png_ptr); |
|
1157 #endif |
|
1158 *png_ptr_ptr = NULL; |
|
1159 } |
|
1160 } |
|
1161 |
|
1162 /* Free all memory used by the read (old method) */ |
|
1163 void /* PRIVATE */ |
|
1164 png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr) |
|
1165 { |
|
1166 #ifdef PNG_SETJMP_SUPPORTED |
|
1167 jmp_buf tmp_jmp; |
|
1168 #endif |
|
1169 png_error_ptr error_fn; |
|
1170 png_error_ptr warning_fn; |
|
1171 png_voidp error_ptr; |
|
1172 #ifdef PNG_USER_MEM_SUPPORTED |
|
1173 png_free_ptr free_fn; |
|
1174 #endif |
|
1175 |
|
1176 png_debug(1, "in png_read_destroy"); |
|
1177 if (info_ptr != NULL) |
|
1178 png_info_destroy(png_ptr, info_ptr); |
|
1179 |
|
1180 if (end_info_ptr != NULL) |
|
1181 png_info_destroy(png_ptr, end_info_ptr); |
|
1182 |
|
1183 png_free(png_ptr, png_ptr->zbuf); |
|
1184 png_free(png_ptr, png_ptr->big_row_buf); |
|
1185 png_free(png_ptr, png_ptr->prev_row); |
|
1186 png_free(png_ptr, png_ptr->chunkdata); |
|
1187 #if defined(PNG_READ_DITHER_SUPPORTED) |
|
1188 png_free(png_ptr, png_ptr->palette_lookup); |
|
1189 png_free(png_ptr, png_ptr->dither_index); |
|
1190 #endif |
|
1191 #if defined(PNG_READ_GAMMA_SUPPORTED) |
|
1192 png_free(png_ptr, png_ptr->gamma_table); |
|
1193 #endif |
|
1194 #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
|
1195 png_free(png_ptr, png_ptr->gamma_from_1); |
|
1196 png_free(png_ptr, png_ptr->gamma_to_1); |
|
1197 #endif |
|
1198 #ifdef PNG_FREE_ME_SUPPORTED |
|
1199 if (png_ptr->free_me & PNG_FREE_PLTE) |
|
1200 png_zfree(png_ptr, png_ptr->palette); |
|
1201 png_ptr->free_me &= ~PNG_FREE_PLTE; |
|
1202 #else |
|
1203 if (png_ptr->flags & PNG_FLAG_FREE_PLTE) |
|
1204 png_zfree(png_ptr, png_ptr->palette); |
|
1205 png_ptr->flags &= ~PNG_FLAG_FREE_PLTE; |
|
1206 #endif |
|
1207 #if defined(PNG_tRNS_SUPPORTED) || \ |
|
1208 defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) |
|
1209 #ifdef PNG_FREE_ME_SUPPORTED |
|
1210 if (png_ptr->free_me & PNG_FREE_TRNS) |
|
1211 png_free(png_ptr, png_ptr->trans); |
|
1212 png_ptr->free_me &= ~PNG_FREE_TRNS; |
|
1213 #else |
|
1214 if (png_ptr->flags & PNG_FLAG_FREE_TRNS) |
|
1215 png_free(png_ptr, png_ptr->trans); |
|
1216 png_ptr->flags &= ~PNG_FLAG_FREE_TRNS; |
|
1217 #endif |
|
1218 #endif |
|
1219 #if defined(PNG_READ_hIST_SUPPORTED) |
|
1220 #ifdef PNG_FREE_ME_SUPPORTED |
|
1221 if (png_ptr->free_me & PNG_FREE_HIST) |
|
1222 png_free(png_ptr, png_ptr->hist); |
|
1223 png_ptr->free_me &= ~PNG_FREE_HIST; |
|
1224 #else |
|
1225 if (png_ptr->flags & PNG_FLAG_FREE_HIST) |
|
1226 png_free(png_ptr, png_ptr->hist); |
|
1227 png_ptr->flags &= ~PNG_FLAG_FREE_HIST; |
|
1228 #endif |
|
1229 #endif |
|
1230 #if defined(PNG_READ_GAMMA_SUPPORTED) |
|
1231 if (png_ptr->gamma_16_table != NULL) |
|
1232 { |
|
1233 int i; |
|
1234 int istop = (1 << (8 - png_ptr->gamma_shift)); |
|
1235 for (i = 0; i < istop; i++) |
|
1236 { |
|
1237 png_free(png_ptr, png_ptr->gamma_16_table[i]); |
|
1238 } |
|
1239 png_free(png_ptr, png_ptr->gamma_16_table); |
|
1240 } |
|
1241 #if defined(PNG_READ_BACKGROUND_SUPPORTED) |
|
1242 if (png_ptr->gamma_16_from_1 != NULL) |
|
1243 { |
|
1244 int i; |
|
1245 int istop = (1 << (8 - png_ptr->gamma_shift)); |
|
1246 for (i = 0; i < istop; i++) |
|
1247 { |
|
1248 png_free(png_ptr, png_ptr->gamma_16_from_1[i]); |
|
1249 } |
|
1250 png_free(png_ptr, png_ptr->gamma_16_from_1); |
|
1251 } |
|
1252 if (png_ptr->gamma_16_to_1 != NULL) |
|
1253 { |
|
1254 int i; |
|
1255 int istop = (1 << (8 - png_ptr->gamma_shift)); |
|
1256 for (i = 0; i < istop; i++) |
|
1257 { |
|
1258 png_free(png_ptr, png_ptr->gamma_16_to_1[i]); |
|
1259 } |
|
1260 png_free(png_ptr, png_ptr->gamma_16_to_1); |
|
1261 } |
|
1262 #endif |
|
1263 #endif |
|
1264 #if defined(PNG_TIME_RFC1123_SUPPORTED) |
|
1265 png_free(png_ptr, png_ptr->time_buffer); |
|
1266 #endif |
|
1267 |
|
1268 inflateEnd(&png_ptr->zstream); |
|
1269 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
1270 png_free(png_ptr, png_ptr->save_buffer); |
|
1271 #endif |
|
1272 |
|
1273 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED |
|
1274 #ifdef PNG_TEXT_SUPPORTED |
|
1275 png_free(png_ptr, png_ptr->current_text); |
|
1276 #endif /* PNG_TEXT_SUPPORTED */ |
|
1277 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ |
|
1278 |
|
1279 /* Save the important info out of the png_struct, in case it is |
|
1280 * being used again. |
|
1281 */ |
|
1282 #ifdef PNG_SETJMP_SUPPORTED |
|
1283 png_memcpy(tmp_jmp, png_ptr->jmpbuf, png_sizeof(jmp_buf)); |
|
1284 #endif |
|
1285 |
|
1286 error_fn = png_ptr->error_fn; |
|
1287 warning_fn = png_ptr->warning_fn; |
|
1288 error_ptr = png_ptr->error_ptr; |
|
1289 #ifdef PNG_USER_MEM_SUPPORTED |
|
1290 free_fn = png_ptr->free_fn; |
|
1291 #endif |
|
1292 |
|
1293 png_memset(png_ptr, 0, png_sizeof(png_struct)); |
|
1294 |
|
1295 png_ptr->error_fn = error_fn; |
|
1296 png_ptr->warning_fn = warning_fn; |
|
1297 png_ptr->error_ptr = error_ptr; |
|
1298 #ifdef PNG_USER_MEM_SUPPORTED |
|
1299 png_ptr->free_fn = free_fn; |
|
1300 #endif |
|
1301 |
|
1302 #ifdef PNG_SETJMP_SUPPORTED |
|
1303 png_memcpy(png_ptr->jmpbuf, tmp_jmp, png_sizeof(jmp_buf)); |
|
1304 #endif |
|
1305 |
|
1306 } |
|
1307 |
|
1308 void PNGAPI |
|
1309 png_set_read_status_fn(png_structp png_ptr, png_read_status_ptr read_row_fn) |
|
1310 { |
|
1311 if (png_ptr == NULL) |
|
1312 return; |
|
1313 png_ptr->read_row_fn = read_row_fn; |
|
1314 } |
|
1315 |
|
1316 |
|
1317 #ifndef PNG_NO_SEQUENTIAL_READ_SUPPORTED |
|
1318 #if defined(PNG_INFO_IMAGE_SUPPORTED) |
|
1319 void PNGAPI |
|
1320 png_read_png(png_structp png_ptr, png_infop info_ptr, |
|
1321 int transforms, |
|
1322 voidp params) |
|
1323 { |
|
1324 int row; |
|
1325 |
|
1326 if (png_ptr == NULL) |
|
1327 return; |
|
1328 #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) |
|
1329 /* Invert the alpha channel from opacity to transparency |
|
1330 */ |
|
1331 if (transforms & PNG_TRANSFORM_INVERT_ALPHA) |
|
1332 png_set_invert_alpha(png_ptr); |
|
1333 #endif |
|
1334 |
|
1335 /* png_read_info() gives us all of the information from the |
|
1336 * PNG file before the first IDAT (image data chunk). |
|
1337 */ |
|
1338 png_read_info(png_ptr, info_ptr); |
|
1339 if (info_ptr->height > PNG_UINT_32_MAX/png_sizeof(png_bytep)) |
|
1340 png_error(png_ptr, "Image is too high to process with png_read_png()"); |
|
1341 |
|
1342 /* -------------- image transformations start here ------------------- */ |
|
1343 |
|
1344 #if defined(PNG_READ_16_TO_8_SUPPORTED) |
|
1345 /* Tell libpng to strip 16 bit/color files down to 8 bits per color. |
|
1346 */ |
|
1347 if (transforms & PNG_TRANSFORM_STRIP_16) |
|
1348 png_set_strip_16(png_ptr); |
|
1349 #endif |
|
1350 |
|
1351 #if defined(PNG_READ_STRIP_ALPHA_SUPPORTED) |
|
1352 /* Strip alpha bytes from the input data without combining with |
|
1353 * the background (not recommended). |
|
1354 */ |
|
1355 if (transforms & PNG_TRANSFORM_STRIP_ALPHA) |
|
1356 png_set_strip_alpha(png_ptr); |
|
1357 #endif |
|
1358 |
|
1359 #if defined(PNG_READ_PACK_SUPPORTED) && !defined(PNG_READ_EXPAND_SUPPORTED) |
|
1360 /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single |
|
1361 * byte into separate bytes (useful for paletted and grayscale images). |
|
1362 */ |
|
1363 if (transforms & PNG_TRANSFORM_PACKING) |
|
1364 png_set_packing(png_ptr); |
|
1365 #endif |
|
1366 |
|
1367 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
1368 /* Change the order of packed pixels to least significant bit first |
|
1369 * (not useful if you are using png_set_packing). |
|
1370 */ |
|
1371 if (transforms & PNG_TRANSFORM_PACKSWAP) |
|
1372 png_set_packswap(png_ptr); |
|
1373 #endif |
|
1374 |
|
1375 #if defined(PNG_READ_EXPAND_SUPPORTED) |
|
1376 /* Expand paletted colors into true RGB triplets |
|
1377 * Expand grayscale images to full 8 bits from 1, 2, or 4 bits/pixel |
|
1378 * Expand paletted or RGB images with transparency to full alpha |
|
1379 * channels so the data will be available as RGBA quartets. |
|
1380 */ |
|
1381 if (transforms & PNG_TRANSFORM_EXPAND) |
|
1382 if ((png_ptr->bit_depth < 8) || |
|
1383 (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) || |
|
1384 (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))) |
|
1385 png_set_expand(png_ptr); |
|
1386 #endif |
|
1387 |
|
1388 /* We don't handle background color or gamma transformation or dithering. |
|
1389 */ |
|
1390 |
|
1391 #if defined(PNG_READ_INVERT_SUPPORTED) |
|
1392 /* Invert monochrome files to have 0 as white and 1 as black |
|
1393 */ |
|
1394 if (transforms & PNG_TRANSFORM_INVERT_MONO) |
|
1395 png_set_invert_mono(png_ptr); |
|
1396 #endif |
|
1397 |
|
1398 #if defined(PNG_READ_SHIFT_SUPPORTED) |
|
1399 /* If you want to shift the pixel values from the range [0,255] or |
|
1400 * [0,65535] to the original [0,7] or [0,31], or whatever range the |
|
1401 * colors were originally in: |
|
1402 */ |
|
1403 if ((transforms & PNG_TRANSFORM_SHIFT) |
|
1404 && png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT)) |
|
1405 { |
|
1406 png_color_8p sig_bit; |
|
1407 |
|
1408 png_get_sBIT(png_ptr, info_ptr, &sig_bit); |
|
1409 png_set_shift(png_ptr, sig_bit); |
|
1410 } |
|
1411 #endif |
|
1412 |
|
1413 #if defined(PNG_READ_BGR_SUPPORTED) |
|
1414 /* Flip the RGB pixels to BGR (or RGBA to BGRA) |
|
1415 */ |
|
1416 if (transforms & PNG_TRANSFORM_BGR) |
|
1417 png_set_bgr(png_ptr); |
|
1418 #endif |
|
1419 |
|
1420 #if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) |
|
1421 /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) |
|
1422 */ |
|
1423 if (transforms & PNG_TRANSFORM_SWAP_ALPHA) |
|
1424 png_set_swap_alpha(png_ptr); |
|
1425 #endif |
|
1426 |
|
1427 #if defined(PNG_READ_SWAP_SUPPORTED) |
|
1428 /* Swap bytes of 16 bit files to least significant byte first |
|
1429 */ |
|
1430 if (transforms & PNG_TRANSFORM_SWAP_ENDIAN) |
|
1431 png_set_swap(png_ptr); |
|
1432 #endif |
|
1433 |
|
1434 /* We don't handle adding filler bytes */ |
|
1435 |
|
1436 /* Optional call to gamma correct and add the background to the palette |
|
1437 * and update info structure. REQUIRED if you are expecting libpng to |
|
1438 * update the palette for you (i.e., you selected such a transform above). |
|
1439 */ |
|
1440 png_read_update_info(png_ptr, info_ptr); |
|
1441 |
|
1442 /* -------------- image transformations end here ------------------- */ |
|
1443 |
|
1444 #ifdef PNG_FREE_ME_SUPPORTED |
|
1445 png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); |
|
1446 #endif |
|
1447 if (info_ptr->row_pointers == NULL) |
|
1448 { |
|
1449 info_ptr->row_pointers = (png_bytepp)png_malloc(png_ptr, |
|
1450 info_ptr->height * png_sizeof(png_bytep)); |
|
1451 png_memset(info_ptr->row_pointers, 0, info_ptr->height |
|
1452 * png_sizeof(png_bytep)); |
|
1453 #ifdef PNG_FREE_ME_SUPPORTED |
|
1454 info_ptr->free_me |= PNG_FREE_ROWS; |
|
1455 #endif |
|
1456 for (row = 0; row < (int)info_ptr->height; row++) |
|
1457 info_ptr->row_pointers[row] = (png_bytep)png_malloc(png_ptr, |
|
1458 png_get_rowbytes(png_ptr, info_ptr)); |
|
1459 } |
|
1460 |
|
1461 png_read_image(png_ptr, info_ptr->row_pointers); |
|
1462 info_ptr->valid |= PNG_INFO_IDAT; |
|
1463 |
|
1464 /* Read rest of file, and get additional chunks in info_ptr - REQUIRED */ |
|
1465 png_read_end(png_ptr, info_ptr); |
|
1466 |
|
1467 transforms = transforms; /* Quiet compiler warnings */ |
|
1468 params = params; |
|
1469 |
|
1470 } |
|
1471 #endif /* PNG_INFO_IMAGE_SUPPORTED */ |
|
1472 #endif /* PNG_NO_SEQUENTIAL_READ_SUPPORTED */ |
|
1473 #endif /* PNG_READ_SUPPORTED */ |