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1 |
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2 /* pngrutil.c - utilities to read a PNG file |
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3 * |
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4 * Last changed in libpng 1.2.31 [August 19, 2008] |
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5 * For conditions of distribution and use, see copyright notice in png.h |
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6 * Copyright (c) 1998-2008 Glenn Randers-Pehrson |
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7 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) |
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8 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) |
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9 * |
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10 * This file contains routines that are only called from within |
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11 * libpng itself during the course of reading an image. |
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12 */ |
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13 |
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14 #define PNG_INTERNAL |
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15 #include "png.h" |
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16 #if defined(PNG_READ_SUPPORTED) |
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17 |
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18 #if defined(_WIN32_WCE) && (_WIN32_WCE<0x500) |
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19 # define WIN32_WCE_OLD |
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20 #endif |
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21 |
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22 #ifdef PNG_FLOATING_POINT_SUPPORTED |
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23 # if defined(WIN32_WCE_OLD) |
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24 /* strtod() function is not supported on WindowsCE */ |
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25 __inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr, char **endptr) |
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26 { |
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27 double result = 0; |
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28 int len; |
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29 wchar_t *str, *end; |
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30 |
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31 len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0); |
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32 str = (wchar_t *)png_malloc(png_ptr, len * png_sizeof(wchar_t)); |
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33 if ( NULL != str ) |
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34 { |
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35 MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len); |
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36 result = wcstod(str, &end); |
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37 len = WideCharToMultiByte(CP_ACP, 0, end, -1, NULL, 0, NULL, NULL); |
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38 *endptr = (char *)nptr + (png_strlen(nptr) - len + 1); |
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39 png_free(png_ptr, str); |
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40 } |
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41 return result; |
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42 } |
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43 # else |
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44 # define png_strtod(p,a,b) strtod(a,b) |
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45 # endif |
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46 #endif |
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47 |
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48 png_uint_32 PNGAPI |
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49 png_get_uint_31(png_structp png_ptr, png_bytep buf) |
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50 { |
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51 #ifdef PNG_READ_BIG_ENDIAN_SUPPORTED |
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52 png_uint_32 i = png_get_uint_32(buf); |
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53 #else |
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54 /* Avoid an extra function call by inlining the result. */ |
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55 png_uint_32 i = ((png_uint_32)(*buf) << 24) + |
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56 ((png_uint_32)(*(buf + 1)) << 16) + |
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57 ((png_uint_32)(*(buf + 2)) << 8) + |
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58 (png_uint_32)(*(buf + 3)); |
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59 #endif |
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60 if (i > PNG_UINT_31_MAX) |
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61 png_error(png_ptr, "PNG unsigned integer out of range."); |
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62 return (i); |
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63 } |
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64 #ifndef PNG_READ_BIG_ENDIAN_SUPPORTED |
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65 /* Grab an unsigned 32-bit integer from a buffer in big-endian format. */ |
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66 png_uint_32 PNGAPI |
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67 png_get_uint_32(png_bytep buf) |
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68 { |
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69 png_uint_32 i = ((png_uint_32)(*buf) << 24) + |
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70 ((png_uint_32)(*(buf + 1)) << 16) + |
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71 ((png_uint_32)(*(buf + 2)) << 8) + |
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72 (png_uint_32)(*(buf + 3)); |
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73 |
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74 return (i); |
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75 } |
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76 |
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77 /* Grab a signed 32-bit integer from a buffer in big-endian format. The |
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78 * data is stored in the PNG file in two's complement format, and it is |
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79 * assumed that the machine format for signed integers is the same. */ |
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80 png_int_32 PNGAPI |
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81 png_get_int_32(png_bytep buf) |
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82 { |
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83 png_int_32 i = ((png_int_32)(*buf) << 24) + |
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84 ((png_int_32)(*(buf + 1)) << 16) + |
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85 ((png_int_32)(*(buf + 2)) << 8) + |
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86 (png_int_32)(*(buf + 3)); |
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87 |
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88 return (i); |
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89 } |
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90 |
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91 /* Grab an unsigned 16-bit integer from a buffer in big-endian format. */ |
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92 png_uint_16 PNGAPI |
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93 png_get_uint_16(png_bytep buf) |
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94 { |
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95 png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) + |
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96 (png_uint_16)(*(buf + 1))); |
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97 |
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98 return (i); |
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99 } |
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100 #endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */ |
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101 |
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102 /* Read the chunk header (length + type name). |
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103 * Put the type name into png_ptr->chunk_name, and return the length. |
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104 */ |
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105 png_uint_32 /* PRIVATE */ |
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106 png_read_chunk_header(png_structp png_ptr) |
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107 { |
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108 png_byte buf[8]; |
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109 png_uint_32 length; |
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110 |
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111 /* read the length and the chunk name */ |
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112 png_read_data(png_ptr, buf, 8); |
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113 length = png_get_uint_31(png_ptr, buf); |
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114 |
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115 /* put the chunk name into png_ptr->chunk_name */ |
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116 png_memcpy(png_ptr->chunk_name, buf + 4, 4); |
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117 |
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118 png_debug2(0, "Reading %s chunk, length = %lu\n", |
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119 png_ptr->chunk_name, length); |
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120 |
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121 /* reset the crc and run it over the chunk name */ |
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122 png_reset_crc(png_ptr); |
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123 png_calculate_crc(png_ptr, png_ptr->chunk_name, 4); |
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124 |
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125 /* check to see if chunk name is valid */ |
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126 png_check_chunk_name(png_ptr, png_ptr->chunk_name); |
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127 |
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128 return length; |
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129 } |
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130 |
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131 /* Read data, and (optionally) run it through the CRC. */ |
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132 void /* PRIVATE */ |
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133 png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length) |
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134 { |
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135 if (png_ptr == NULL) return; |
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136 png_read_data(png_ptr, buf, length); |
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137 png_calculate_crc(png_ptr, buf, length); |
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138 } |
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139 |
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140 /* Optionally skip data and then check the CRC. Depending on whether we |
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141 are reading a ancillary or critical chunk, and how the program has set |
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142 things up, we may calculate the CRC on the data and print a message. |
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143 Returns '1' if there was a CRC error, '0' otherwise. */ |
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144 int /* PRIVATE */ |
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145 png_crc_finish(png_structp png_ptr, png_uint_32 skip) |
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146 { |
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147 png_size_t i; |
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148 png_size_t istop = png_ptr->zbuf_size; |
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149 |
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150 for (i = (png_size_t)skip; i > istop; i -= istop) |
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151 { |
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152 png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size); |
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153 } |
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154 if (i) |
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155 { |
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156 png_crc_read(png_ptr, png_ptr->zbuf, i); |
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157 } |
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158 |
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159 if (png_crc_error(png_ptr)) |
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160 { |
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161 if (((png_ptr->chunk_name[0] & 0x20) && /* Ancillary */ |
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162 !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) || |
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163 (!(png_ptr->chunk_name[0] & 0x20) && /* Critical */ |
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164 (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE))) |
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165 { |
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166 png_chunk_warning(png_ptr, "CRC error"); |
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167 } |
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168 else |
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169 { |
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170 png_chunk_error(png_ptr, "CRC error"); |
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171 } |
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172 return (1); |
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173 } |
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174 |
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175 return (0); |
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176 } |
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177 |
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178 /* Compare the CRC stored in the PNG file with that calculated by libpng from |
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179 the data it has read thus far. */ |
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180 int /* PRIVATE */ |
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181 png_crc_error(png_structp png_ptr) |
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182 { |
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183 png_byte crc_bytes[4]; |
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184 png_uint_32 crc; |
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185 int need_crc = 1; |
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186 |
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187 if (png_ptr->chunk_name[0] & 0x20) /* ancillary */ |
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188 { |
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189 if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) == |
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190 (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN)) |
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191 need_crc = 0; |
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192 } |
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193 else /* critical */ |
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194 { |
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195 if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE) |
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196 need_crc = 0; |
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197 } |
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198 |
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199 png_read_data(png_ptr, crc_bytes, 4); |
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200 |
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201 if (need_crc) |
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202 { |
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203 crc = png_get_uint_32(crc_bytes); |
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204 return ((int)(crc != png_ptr->crc)); |
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205 } |
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206 else |
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207 return (0); |
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208 } |
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209 |
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210 #if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \ |
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211 defined(PNG_READ_iCCP_SUPPORTED) |
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212 /* |
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213 * Decompress trailing data in a chunk. The assumption is that chunkdata |
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214 * points at an allocated area holding the contents of a chunk with a |
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215 * trailing compressed part. What we get back is an allocated area |
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216 * holding the original prefix part and an uncompressed version of the |
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217 * trailing part (the malloc area passed in is freed). |
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218 */ |
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219 void /* PRIVATE */ |
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220 png_decompress_chunk(png_structp png_ptr, int comp_type, |
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221 png_size_t chunklength, |
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222 png_size_t prefix_size, png_size_t *newlength) |
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223 { |
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224 static PNG_CONST char msg[] = "Error decoding compressed text"; |
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225 png_charp text; |
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226 png_size_t text_size; |
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227 |
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228 if (comp_type == PNG_COMPRESSION_TYPE_BASE) |
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229 { |
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230 int ret = Z_OK; |
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231 png_ptr->zstream.next_in = (png_bytep)(png_ptr->chunkdata + prefix_size); |
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232 png_ptr->zstream.avail_in = (uInt)(chunklength - prefix_size); |
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233 png_ptr->zstream.next_out = png_ptr->zbuf; |
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234 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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235 |
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236 text_size = 0; |
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237 text = NULL; |
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238 |
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239 while (png_ptr->zstream.avail_in) |
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240 { |
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241 ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); |
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242 if (ret != Z_OK && ret != Z_STREAM_END) |
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243 { |
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244 if (png_ptr->zstream.msg != NULL) |
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245 png_warning(png_ptr, png_ptr->zstream.msg); |
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246 else |
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247 png_warning(png_ptr, msg); |
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248 inflateReset(&png_ptr->zstream); |
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249 png_ptr->zstream.avail_in = 0; |
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250 |
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251 if (text == NULL) |
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252 { |
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253 text_size = prefix_size + png_sizeof(msg) + 1; |
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254 text = (png_charp)png_malloc_warn(png_ptr, text_size); |
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255 if (text == NULL) |
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256 { |
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257 png_free(png_ptr, png_ptr->chunkdata); |
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258 png_ptr->chunkdata = NULL; |
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259 png_error(png_ptr, "Not enough memory to decompress chunk"); |
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260 } |
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261 png_memcpy(text, png_ptr->chunkdata, prefix_size); |
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262 } |
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263 |
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264 text[text_size - 1] = 0x00; |
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265 |
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266 /* Copy what we can of the error message into the text chunk */ |
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267 text_size = (png_size_t)(chunklength - |
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268 (text - png_ptr->chunkdata) - 1); |
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269 if (text_size > png_sizeof(msg)) |
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270 text_size = png_sizeof(msg); |
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271 png_memcpy(text + prefix_size, msg, text_size); |
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272 break; |
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273 } |
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274 if (!png_ptr->zstream.avail_out || ret == Z_STREAM_END) |
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275 { |
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276 if (text == NULL) |
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277 { |
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278 text_size = prefix_size + |
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279 png_ptr->zbuf_size - png_ptr->zstream.avail_out; |
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280 text = (png_charp)png_malloc_warn(png_ptr, text_size + 1); |
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281 if (text == NULL) |
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282 { |
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283 png_free(png_ptr, png_ptr->chunkdata); |
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284 png_ptr->chunkdata = NULL; |
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285 png_error(png_ptr, |
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286 "Not enough memory to decompress chunk."); |
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287 } |
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288 png_memcpy(text + prefix_size, png_ptr->zbuf, |
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289 text_size - prefix_size); |
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290 png_memcpy(text, png_ptr->chunkdata, prefix_size); |
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291 *(text + text_size) = 0x00; |
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292 } |
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293 else |
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294 { |
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295 png_charp tmp; |
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296 |
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297 tmp = text; |
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298 text = (png_charp)png_malloc_warn(png_ptr, |
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299 (png_uint_32)(text_size + |
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300 png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1)); |
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301 if (text == NULL) |
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302 { |
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303 png_free(png_ptr, tmp); |
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304 png_free(png_ptr, png_ptr->chunkdata); |
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305 png_ptr->chunkdata = NULL; |
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306 png_error(png_ptr, |
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307 "Not enough memory to decompress chunk.."); |
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308 } |
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309 png_memcpy(text, tmp, text_size); |
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310 png_free(png_ptr, tmp); |
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311 png_memcpy(text + text_size, png_ptr->zbuf, |
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312 (png_ptr->zbuf_size - png_ptr->zstream.avail_out)); |
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313 text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out; |
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314 *(text + text_size) = 0x00; |
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315 } |
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316 if (ret == Z_STREAM_END) |
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317 break; |
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318 else |
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319 { |
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320 png_ptr->zstream.next_out = png_ptr->zbuf; |
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321 png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size; |
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322 } |
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323 } |
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324 } |
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325 if (ret != Z_STREAM_END) |
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326 { |
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327 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
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328 char umsg[52]; |
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329 |
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330 if (ret == Z_BUF_ERROR) |
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331 png_snprintf(umsg, 52, |
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332 "Buffer error in compressed datastream in %s chunk", |
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333 png_ptr->chunk_name); |
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334 else if (ret == Z_DATA_ERROR) |
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335 png_snprintf(umsg, 52, |
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336 "Data error in compressed datastream in %s chunk", |
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337 png_ptr->chunk_name); |
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338 else |
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339 png_snprintf(umsg, 52, |
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340 "Incomplete compressed datastream in %s chunk", |
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341 png_ptr->chunk_name); |
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342 png_warning(png_ptr, umsg); |
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343 #else |
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344 png_warning(png_ptr, |
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345 "Incomplete compressed datastream in chunk other than IDAT"); |
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346 #endif |
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347 text_size = prefix_size; |
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348 if (text == NULL) |
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349 { |
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350 text = (png_charp)png_malloc_warn(png_ptr, text_size+1); |
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351 if (text == NULL) |
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352 { |
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353 png_free(png_ptr, png_ptr->chunkdata); |
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354 png_ptr->chunkdata = NULL; |
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355 png_error(png_ptr, "Not enough memory for text."); |
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356 } |
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357 png_memcpy(text, png_ptr->chunkdata, prefix_size); |
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358 } |
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359 *(text + text_size) = 0x00; |
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360 } |
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361 |
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362 inflateReset(&png_ptr->zstream); |
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363 png_ptr->zstream.avail_in = 0; |
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364 |
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365 png_free(png_ptr, png_ptr->chunkdata); |
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366 png_ptr->chunkdata = text; |
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367 *newlength=text_size; |
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368 } |
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369 else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */ |
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370 { |
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371 #if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE) |
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372 char umsg[50]; |
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373 |
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374 png_snprintf(umsg, 50, "Unknown zTXt compression type %d", comp_type); |
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375 png_warning(png_ptr, umsg); |
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376 #else |
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377 png_warning(png_ptr, "Unknown zTXt compression type"); |
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378 #endif |
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379 |
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380 *(png_ptr->chunkdata + prefix_size) = 0x00; |
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381 *newlength = prefix_size; |
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382 } |
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383 } |
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384 #endif |
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385 |
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386 /* read and check the IDHR chunk */ |
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387 void /* PRIVATE */ |
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388 png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
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389 { |
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390 png_byte buf[13]; |
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391 png_uint_32 width, height; |
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392 int bit_depth, color_type, compression_type, filter_type; |
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393 int interlace_type; |
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394 |
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395 png_debug(1, "in png_handle_IHDR\n"); |
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396 |
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397 if (png_ptr->mode & PNG_HAVE_IHDR) |
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398 png_error(png_ptr, "Out of place IHDR"); |
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399 |
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400 /* check the length */ |
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401 if (length != 13) |
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402 png_error(png_ptr, "Invalid IHDR chunk"); |
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403 |
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404 png_ptr->mode |= PNG_HAVE_IHDR; |
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405 |
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406 png_crc_read(png_ptr, buf, 13); |
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407 png_crc_finish(png_ptr, 0); |
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408 |
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409 width = png_get_uint_31(png_ptr, buf); |
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410 height = png_get_uint_31(png_ptr, buf + 4); |
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411 bit_depth = buf[8]; |
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412 color_type = buf[9]; |
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413 compression_type = buf[10]; |
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414 filter_type = buf[11]; |
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415 interlace_type = buf[12]; |
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416 |
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417 /* set internal variables */ |
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418 png_ptr->width = width; |
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419 png_ptr->height = height; |
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420 png_ptr->bit_depth = (png_byte)bit_depth; |
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421 png_ptr->interlaced = (png_byte)interlace_type; |
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422 png_ptr->color_type = (png_byte)color_type; |
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423 #if defined(PNG_MNG_FEATURES_SUPPORTED) |
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424 png_ptr->filter_type = (png_byte)filter_type; |
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425 #endif |
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426 png_ptr->compression_type = (png_byte)compression_type; |
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427 |
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428 /* find number of channels */ |
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429 switch (png_ptr->color_type) |
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430 { |
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431 case PNG_COLOR_TYPE_GRAY: |
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432 case PNG_COLOR_TYPE_PALETTE: |
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433 png_ptr->channels = 1; |
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434 break; |
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435 case PNG_COLOR_TYPE_RGB: |
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436 png_ptr->channels = 3; |
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437 break; |
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438 case PNG_COLOR_TYPE_GRAY_ALPHA: |
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439 png_ptr->channels = 2; |
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440 break; |
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441 case PNG_COLOR_TYPE_RGB_ALPHA: |
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442 png_ptr->channels = 4; |
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443 break; |
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444 } |
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445 |
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446 /* set up other useful info */ |
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447 png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth * |
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448 png_ptr->channels); |
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449 png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width); |
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450 png_debug1(3, "bit_depth = %d\n", png_ptr->bit_depth); |
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451 png_debug1(3, "channels = %d\n", png_ptr->channels); |
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452 png_debug1(3, "rowbytes = %lu\n", png_ptr->rowbytes); |
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453 png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, |
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454 color_type, interlace_type, compression_type, filter_type); |
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455 } |
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456 |
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457 /* read and check the palette */ |
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458 void /* PRIVATE */ |
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459 png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
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460 { |
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461 png_color palette[PNG_MAX_PALETTE_LENGTH]; |
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462 int num, i; |
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463 #ifndef PNG_NO_POINTER_INDEXING |
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464 png_colorp pal_ptr; |
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465 #endif |
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466 |
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467 png_debug(1, "in png_handle_PLTE\n"); |
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468 |
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469 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
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470 png_error(png_ptr, "Missing IHDR before PLTE"); |
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471 else if (png_ptr->mode & PNG_HAVE_IDAT) |
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472 { |
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473 png_warning(png_ptr, "Invalid PLTE after IDAT"); |
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474 png_crc_finish(png_ptr, length); |
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475 return; |
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476 } |
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477 else if (png_ptr->mode & PNG_HAVE_PLTE) |
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478 png_error(png_ptr, "Duplicate PLTE chunk"); |
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479 |
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480 png_ptr->mode |= PNG_HAVE_PLTE; |
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481 |
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482 if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR)) |
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483 { |
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484 png_warning(png_ptr, |
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485 "Ignoring PLTE chunk in grayscale PNG"); |
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486 png_crc_finish(png_ptr, length); |
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487 return; |
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488 } |
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489 #if !defined(PNG_READ_OPT_PLTE_SUPPORTED) |
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490 if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE) |
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491 { |
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492 png_crc_finish(png_ptr, length); |
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493 return; |
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494 } |
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495 #endif |
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496 |
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497 if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3) |
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498 { |
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499 if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE) |
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500 { |
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501 png_warning(png_ptr, "Invalid palette chunk"); |
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502 png_crc_finish(png_ptr, length); |
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503 return; |
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504 } |
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505 else |
|
506 { |
|
507 png_error(png_ptr, "Invalid palette chunk"); |
|
508 } |
|
509 } |
|
510 |
|
511 num = (int)length / 3; |
|
512 |
|
513 #ifndef PNG_NO_POINTER_INDEXING |
|
514 for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++) |
|
515 { |
|
516 png_byte buf[3]; |
|
517 |
|
518 png_crc_read(png_ptr, buf, 3); |
|
519 pal_ptr->red = buf[0]; |
|
520 pal_ptr->green = buf[1]; |
|
521 pal_ptr->blue = buf[2]; |
|
522 } |
|
523 #else |
|
524 for (i = 0; i < num; i++) |
|
525 { |
|
526 png_byte buf[3]; |
|
527 |
|
528 png_crc_read(png_ptr, buf, 3); |
|
529 /* don't depend upon png_color being any order */ |
|
530 palette[i].red = buf[0]; |
|
531 palette[i].green = buf[1]; |
|
532 palette[i].blue = buf[2]; |
|
533 } |
|
534 #endif |
|
535 |
|
536 /* If we actually NEED the PLTE chunk (ie for a paletted image), we do |
|
537 whatever the normal CRC configuration tells us. However, if we |
|
538 have an RGB image, the PLTE can be considered ancillary, so |
|
539 we will act as though it is. */ |
|
540 #if !defined(PNG_READ_OPT_PLTE_SUPPORTED) |
|
541 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
542 #endif |
|
543 { |
|
544 png_crc_finish(png_ptr, 0); |
|
545 } |
|
546 #if !defined(PNG_READ_OPT_PLTE_SUPPORTED) |
|
547 else if (png_crc_error(png_ptr)) /* Only if we have a CRC error */ |
|
548 { |
|
549 /* If we don't want to use the data from an ancillary chunk, |
|
550 we have two options: an error abort, or a warning and we |
|
551 ignore the data in this chunk (which should be OK, since |
|
552 it's considered ancillary for a RGB or RGBA image). */ |
|
553 if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE)) |
|
554 { |
|
555 if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) |
|
556 { |
|
557 png_chunk_error(png_ptr, "CRC error"); |
|
558 } |
|
559 else |
|
560 { |
|
561 png_chunk_warning(png_ptr, "CRC error"); |
|
562 return; |
|
563 } |
|
564 } |
|
565 /* Otherwise, we (optionally) emit a warning and use the chunk. */ |
|
566 else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) |
|
567 { |
|
568 png_chunk_warning(png_ptr, "CRC error"); |
|
569 } |
|
570 } |
|
571 #endif |
|
572 |
|
573 png_set_PLTE(png_ptr, info_ptr, palette, num); |
|
574 |
|
575 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
576 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
577 { |
|
578 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS)) |
|
579 { |
|
580 if (png_ptr->num_trans > (png_uint_16)num) |
|
581 { |
|
582 png_warning(png_ptr, "Truncating incorrect tRNS chunk length"); |
|
583 png_ptr->num_trans = (png_uint_16)num; |
|
584 } |
|
585 if (info_ptr->num_trans > (png_uint_16)num) |
|
586 { |
|
587 png_warning(png_ptr, "Truncating incorrect info tRNS chunk length"); |
|
588 info_ptr->num_trans = (png_uint_16)num; |
|
589 } |
|
590 } |
|
591 } |
|
592 #endif |
|
593 |
|
594 } |
|
595 |
|
596 void /* PRIVATE */ |
|
597 png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
598 { |
|
599 png_debug(1, "in png_handle_IEND\n"); |
|
600 |
|
601 if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT)) |
|
602 { |
|
603 png_error(png_ptr, "No image in file"); |
|
604 } |
|
605 |
|
606 png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND); |
|
607 |
|
608 if (length != 0) |
|
609 { |
|
610 png_warning(png_ptr, "Incorrect IEND chunk length"); |
|
611 } |
|
612 png_crc_finish(png_ptr, length); |
|
613 |
|
614 info_ptr = info_ptr; /* quiet compiler warnings about unused info_ptr */ |
|
615 } |
|
616 |
|
617 #if defined(PNG_READ_gAMA_SUPPORTED) |
|
618 void /* PRIVATE */ |
|
619 png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
620 { |
|
621 png_fixed_point igamma; |
|
622 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
623 float file_gamma; |
|
624 #endif |
|
625 png_byte buf[4]; |
|
626 |
|
627 png_debug(1, "in png_handle_gAMA\n"); |
|
628 |
|
629 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
630 png_error(png_ptr, "Missing IHDR before gAMA"); |
|
631 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
632 { |
|
633 png_warning(png_ptr, "Invalid gAMA after IDAT"); |
|
634 png_crc_finish(png_ptr, length); |
|
635 return; |
|
636 } |
|
637 else if (png_ptr->mode & PNG_HAVE_PLTE) |
|
638 /* Should be an error, but we can cope with it */ |
|
639 png_warning(png_ptr, "Out of place gAMA chunk"); |
|
640 |
|
641 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA) |
|
642 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
643 && !(info_ptr->valid & PNG_INFO_sRGB) |
|
644 #endif |
|
645 ) |
|
646 { |
|
647 png_warning(png_ptr, "Duplicate gAMA chunk"); |
|
648 png_crc_finish(png_ptr, length); |
|
649 return; |
|
650 } |
|
651 |
|
652 if (length != 4) |
|
653 { |
|
654 png_warning(png_ptr, "Incorrect gAMA chunk length"); |
|
655 png_crc_finish(png_ptr, length); |
|
656 return; |
|
657 } |
|
658 |
|
659 png_crc_read(png_ptr, buf, 4); |
|
660 if (png_crc_finish(png_ptr, 0)) |
|
661 return; |
|
662 |
|
663 igamma = (png_fixed_point)png_get_uint_32(buf); |
|
664 /* check for zero gamma */ |
|
665 if (igamma == 0) |
|
666 { |
|
667 png_warning(png_ptr, |
|
668 "Ignoring gAMA chunk with gamma=0"); |
|
669 return; |
|
670 } |
|
671 |
|
672 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
673 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)) |
|
674 if (PNG_OUT_OF_RANGE(igamma, 45500L, 500)) |
|
675 { |
|
676 png_warning(png_ptr, |
|
677 "Ignoring incorrect gAMA value when sRGB is also present"); |
|
678 #ifndef PNG_NO_CONSOLE_IO |
|
679 fprintf(stderr, "gamma = (%d/100000)\n", (int)igamma); |
|
680 #endif |
|
681 return; |
|
682 } |
|
683 #endif /* PNG_READ_sRGB_SUPPORTED */ |
|
684 |
|
685 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
686 file_gamma = (float)igamma / (float)100000.0; |
|
687 # ifdef PNG_READ_GAMMA_SUPPORTED |
|
688 png_ptr->gamma = file_gamma; |
|
689 # endif |
|
690 png_set_gAMA(png_ptr, info_ptr, file_gamma); |
|
691 #endif |
|
692 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
693 png_set_gAMA_fixed(png_ptr, info_ptr, igamma); |
|
694 #endif |
|
695 } |
|
696 #endif |
|
697 |
|
698 #if defined(PNG_READ_sBIT_SUPPORTED) |
|
699 void /* PRIVATE */ |
|
700 png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
701 { |
|
702 png_size_t truelen; |
|
703 png_byte buf[4]; |
|
704 |
|
705 png_debug(1, "in png_handle_sBIT\n"); |
|
706 |
|
707 buf[0] = buf[1] = buf[2] = buf[3] = 0; |
|
708 |
|
709 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
710 png_error(png_ptr, "Missing IHDR before sBIT"); |
|
711 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
712 { |
|
713 png_warning(png_ptr, "Invalid sBIT after IDAT"); |
|
714 png_crc_finish(png_ptr, length); |
|
715 return; |
|
716 } |
|
717 else if (png_ptr->mode & PNG_HAVE_PLTE) |
|
718 { |
|
719 /* Should be an error, but we can cope with it */ |
|
720 png_warning(png_ptr, "Out of place sBIT chunk"); |
|
721 } |
|
722 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)) |
|
723 { |
|
724 png_warning(png_ptr, "Duplicate sBIT chunk"); |
|
725 png_crc_finish(png_ptr, length); |
|
726 return; |
|
727 } |
|
728 |
|
729 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
730 truelen = 3; |
|
731 else |
|
732 truelen = (png_size_t)png_ptr->channels; |
|
733 |
|
734 if (length != truelen || length > 4) |
|
735 { |
|
736 png_warning(png_ptr, "Incorrect sBIT chunk length"); |
|
737 png_crc_finish(png_ptr, length); |
|
738 return; |
|
739 } |
|
740 |
|
741 png_crc_read(png_ptr, buf, truelen); |
|
742 if (png_crc_finish(png_ptr, 0)) |
|
743 return; |
|
744 |
|
745 if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) |
|
746 { |
|
747 png_ptr->sig_bit.red = buf[0]; |
|
748 png_ptr->sig_bit.green = buf[1]; |
|
749 png_ptr->sig_bit.blue = buf[2]; |
|
750 png_ptr->sig_bit.alpha = buf[3]; |
|
751 } |
|
752 else |
|
753 { |
|
754 png_ptr->sig_bit.gray = buf[0]; |
|
755 png_ptr->sig_bit.red = buf[0]; |
|
756 png_ptr->sig_bit.green = buf[0]; |
|
757 png_ptr->sig_bit.blue = buf[0]; |
|
758 png_ptr->sig_bit.alpha = buf[1]; |
|
759 } |
|
760 png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit)); |
|
761 } |
|
762 #endif |
|
763 |
|
764 #if defined(PNG_READ_cHRM_SUPPORTED) |
|
765 void /* PRIVATE */ |
|
766 png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
767 { |
|
768 png_byte buf[32]; |
|
769 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
770 float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y; |
|
771 #endif |
|
772 png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green, |
|
773 int_y_green, int_x_blue, int_y_blue; |
|
774 |
|
775 png_uint_32 uint_x, uint_y; |
|
776 |
|
777 png_debug(1, "in png_handle_cHRM\n"); |
|
778 |
|
779 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
780 png_error(png_ptr, "Missing IHDR before cHRM"); |
|
781 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
782 { |
|
783 png_warning(png_ptr, "Invalid cHRM after IDAT"); |
|
784 png_crc_finish(png_ptr, length); |
|
785 return; |
|
786 } |
|
787 else if (png_ptr->mode & PNG_HAVE_PLTE) |
|
788 /* Should be an error, but we can cope with it */ |
|
789 png_warning(png_ptr, "Missing PLTE before cHRM"); |
|
790 |
|
791 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM) |
|
792 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
793 && !(info_ptr->valid & PNG_INFO_sRGB) |
|
794 #endif |
|
795 ) |
|
796 { |
|
797 png_warning(png_ptr, "Duplicate cHRM chunk"); |
|
798 png_crc_finish(png_ptr, length); |
|
799 return; |
|
800 } |
|
801 |
|
802 if (length != 32) |
|
803 { |
|
804 png_warning(png_ptr, "Incorrect cHRM chunk length"); |
|
805 png_crc_finish(png_ptr, length); |
|
806 return; |
|
807 } |
|
808 |
|
809 png_crc_read(png_ptr, buf, 32); |
|
810 if (png_crc_finish(png_ptr, 0)) |
|
811 return; |
|
812 |
|
813 uint_x = png_get_uint_32(buf); |
|
814 uint_y = png_get_uint_32(buf + 4); |
|
815 if (uint_x > 80000L || uint_y > 80000L || |
|
816 uint_x + uint_y > 100000L) |
|
817 { |
|
818 png_warning(png_ptr, "Invalid cHRM white point"); |
|
819 return; |
|
820 } |
|
821 int_x_white = (png_fixed_point)uint_x; |
|
822 int_y_white = (png_fixed_point)uint_y; |
|
823 |
|
824 uint_x = png_get_uint_32(buf + 8); |
|
825 uint_y = png_get_uint_32(buf + 12); |
|
826 if (uint_x + uint_y > 100000L) |
|
827 { |
|
828 png_warning(png_ptr, "Invalid cHRM red point"); |
|
829 return; |
|
830 } |
|
831 int_x_red = (png_fixed_point)uint_x; |
|
832 int_y_red = (png_fixed_point)uint_y; |
|
833 |
|
834 uint_x = png_get_uint_32(buf + 16); |
|
835 uint_y = png_get_uint_32(buf + 20); |
|
836 if (uint_x + uint_y > 100000L) |
|
837 { |
|
838 png_warning(png_ptr, "Invalid cHRM green point"); |
|
839 return; |
|
840 } |
|
841 int_x_green = (png_fixed_point)uint_x; |
|
842 int_y_green = (png_fixed_point)uint_y; |
|
843 |
|
844 uint_x = png_get_uint_32(buf + 24); |
|
845 uint_y = png_get_uint_32(buf + 28); |
|
846 if (uint_x + uint_y > 100000L) |
|
847 { |
|
848 png_warning(png_ptr, "Invalid cHRM blue point"); |
|
849 return; |
|
850 } |
|
851 int_x_blue = (png_fixed_point)uint_x; |
|
852 int_y_blue = (png_fixed_point)uint_y; |
|
853 |
|
854 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
855 white_x = (float)int_x_white / (float)100000.0; |
|
856 white_y = (float)int_y_white / (float)100000.0; |
|
857 red_x = (float)int_x_red / (float)100000.0; |
|
858 red_y = (float)int_y_red / (float)100000.0; |
|
859 green_x = (float)int_x_green / (float)100000.0; |
|
860 green_y = (float)int_y_green / (float)100000.0; |
|
861 blue_x = (float)int_x_blue / (float)100000.0; |
|
862 blue_y = (float)int_y_blue / (float)100000.0; |
|
863 #endif |
|
864 |
|
865 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
866 if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB)) |
|
867 { |
|
868 if (PNG_OUT_OF_RANGE(int_x_white, 31270, 1000) || |
|
869 PNG_OUT_OF_RANGE(int_y_white, 32900, 1000) || |
|
870 PNG_OUT_OF_RANGE(int_x_red, 64000L, 1000) || |
|
871 PNG_OUT_OF_RANGE(int_y_red, 33000, 1000) || |
|
872 PNG_OUT_OF_RANGE(int_x_green, 30000, 1000) || |
|
873 PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) || |
|
874 PNG_OUT_OF_RANGE(int_x_blue, 15000, 1000) || |
|
875 PNG_OUT_OF_RANGE(int_y_blue, 6000, 1000)) |
|
876 { |
|
877 png_warning(png_ptr, |
|
878 "Ignoring incorrect cHRM value when sRGB is also present"); |
|
879 #ifndef PNG_NO_CONSOLE_IO |
|
880 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
881 fprintf(stderr, "wx=%f, wy=%f, rx=%f, ry=%f\n", |
|
882 white_x, white_y, red_x, red_y); |
|
883 fprintf(stderr, "gx=%f, gy=%f, bx=%f, by=%f\n", |
|
884 green_x, green_y, blue_x, blue_y); |
|
885 #else |
|
886 fprintf(stderr, "wx=%ld, wy=%ld, rx=%ld, ry=%ld\n", |
|
887 int_x_white, int_y_white, int_x_red, int_y_red); |
|
888 fprintf(stderr, "gx=%ld, gy=%ld, bx=%ld, by=%ld\n", |
|
889 int_x_green, int_y_green, int_x_blue, int_y_blue); |
|
890 #endif |
|
891 #endif /* PNG_NO_CONSOLE_IO */ |
|
892 } |
|
893 return; |
|
894 } |
|
895 #endif /* PNG_READ_sRGB_SUPPORTED */ |
|
896 |
|
897 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
898 png_set_cHRM(png_ptr, info_ptr, |
|
899 white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y); |
|
900 #endif |
|
901 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
902 png_set_cHRM_fixed(png_ptr, info_ptr, |
|
903 int_x_white, int_y_white, int_x_red, int_y_red, int_x_green, |
|
904 int_y_green, int_x_blue, int_y_blue); |
|
905 #endif |
|
906 } |
|
907 #endif |
|
908 |
|
909 #if defined(PNG_READ_sRGB_SUPPORTED) |
|
910 void /* PRIVATE */ |
|
911 png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
912 { |
|
913 int intent; |
|
914 png_byte buf[1]; |
|
915 |
|
916 png_debug(1, "in png_handle_sRGB\n"); |
|
917 |
|
918 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
919 png_error(png_ptr, "Missing IHDR before sRGB"); |
|
920 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
921 { |
|
922 png_warning(png_ptr, "Invalid sRGB after IDAT"); |
|
923 png_crc_finish(png_ptr, length); |
|
924 return; |
|
925 } |
|
926 else if (png_ptr->mode & PNG_HAVE_PLTE) |
|
927 /* Should be an error, but we can cope with it */ |
|
928 png_warning(png_ptr, "Out of place sRGB chunk"); |
|
929 |
|
930 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)) |
|
931 { |
|
932 png_warning(png_ptr, "Duplicate sRGB chunk"); |
|
933 png_crc_finish(png_ptr, length); |
|
934 return; |
|
935 } |
|
936 |
|
937 if (length != 1) |
|
938 { |
|
939 png_warning(png_ptr, "Incorrect sRGB chunk length"); |
|
940 png_crc_finish(png_ptr, length); |
|
941 return; |
|
942 } |
|
943 |
|
944 png_crc_read(png_ptr, buf, 1); |
|
945 if (png_crc_finish(png_ptr, 0)) |
|
946 return; |
|
947 |
|
948 intent = buf[0]; |
|
949 /* check for bad intent */ |
|
950 if (intent >= PNG_sRGB_INTENT_LAST) |
|
951 { |
|
952 png_warning(png_ptr, "Unknown sRGB intent"); |
|
953 return; |
|
954 } |
|
955 |
|
956 #if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED) |
|
957 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)) |
|
958 { |
|
959 png_fixed_point igamma; |
|
960 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
961 igamma=info_ptr->int_gamma; |
|
962 #else |
|
963 # ifdef PNG_FLOATING_POINT_SUPPORTED |
|
964 igamma=(png_fixed_point)(info_ptr->gamma * 100000.); |
|
965 # endif |
|
966 #endif |
|
967 if (PNG_OUT_OF_RANGE(igamma, 45500L, 500)) |
|
968 { |
|
969 png_warning(png_ptr, |
|
970 "Ignoring incorrect gAMA value when sRGB is also present"); |
|
971 #ifndef PNG_NO_CONSOLE_IO |
|
972 # ifdef PNG_FIXED_POINT_SUPPORTED |
|
973 fprintf(stderr, "incorrect gamma=(%d/100000)\n", |
|
974 (int)png_ptr->int_gamma); |
|
975 # else |
|
976 # ifdef PNG_FLOATING_POINT_SUPPORTED |
|
977 fprintf(stderr, "incorrect gamma=%f\n", png_ptr->gamma); |
|
978 # endif |
|
979 # endif |
|
980 #endif |
|
981 } |
|
982 } |
|
983 #endif /* PNG_READ_gAMA_SUPPORTED */ |
|
984 |
|
985 #ifdef PNG_READ_cHRM_SUPPORTED |
|
986 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
987 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)) |
|
988 if (PNG_OUT_OF_RANGE(info_ptr->int_x_white, 31270, 1000) || |
|
989 PNG_OUT_OF_RANGE(info_ptr->int_y_white, 32900, 1000) || |
|
990 PNG_OUT_OF_RANGE(info_ptr->int_x_red, 64000L, 1000) || |
|
991 PNG_OUT_OF_RANGE(info_ptr->int_y_red, 33000, 1000) || |
|
992 PNG_OUT_OF_RANGE(info_ptr->int_x_green, 30000, 1000) || |
|
993 PNG_OUT_OF_RANGE(info_ptr->int_y_green, 60000L, 1000) || |
|
994 PNG_OUT_OF_RANGE(info_ptr->int_x_blue, 15000, 1000) || |
|
995 PNG_OUT_OF_RANGE(info_ptr->int_y_blue, 6000, 1000)) |
|
996 { |
|
997 png_warning(png_ptr, |
|
998 "Ignoring incorrect cHRM value when sRGB is also present"); |
|
999 } |
|
1000 #endif /* PNG_FIXED_POINT_SUPPORTED */ |
|
1001 #endif /* PNG_READ_cHRM_SUPPORTED */ |
|
1002 |
|
1003 png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent); |
|
1004 } |
|
1005 #endif /* PNG_READ_sRGB_SUPPORTED */ |
|
1006 |
|
1007 #if defined(PNG_READ_iCCP_SUPPORTED) |
|
1008 void /* PRIVATE */ |
|
1009 png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1010 /* Note: this does not properly handle chunks that are > 64K under DOS */ |
|
1011 { |
|
1012 png_byte compression_type; |
|
1013 png_bytep pC; |
|
1014 png_charp profile; |
|
1015 png_uint_32 skip = 0; |
|
1016 png_uint_32 profile_size, profile_length; |
|
1017 png_size_t slength, prefix_length, data_length; |
|
1018 |
|
1019 png_debug(1, "in png_handle_iCCP\n"); |
|
1020 |
|
1021 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1022 png_error(png_ptr, "Missing IHDR before iCCP"); |
|
1023 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1024 { |
|
1025 png_warning(png_ptr, "Invalid iCCP after IDAT"); |
|
1026 png_crc_finish(png_ptr, length); |
|
1027 return; |
|
1028 } |
|
1029 else if (png_ptr->mode & PNG_HAVE_PLTE) |
|
1030 /* Should be an error, but we can cope with it */ |
|
1031 png_warning(png_ptr, "Out of place iCCP chunk"); |
|
1032 |
|
1033 if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)) |
|
1034 { |
|
1035 png_warning(png_ptr, "Duplicate iCCP chunk"); |
|
1036 png_crc_finish(png_ptr, length); |
|
1037 return; |
|
1038 } |
|
1039 |
|
1040 #ifdef PNG_MAX_MALLOC_64K |
|
1041 if (length > (png_uint_32)65535L) |
|
1042 { |
|
1043 png_warning(png_ptr, "iCCP chunk too large to fit in memory"); |
|
1044 skip = length - (png_uint_32)65535L; |
|
1045 length = (png_uint_32)65535L; |
|
1046 } |
|
1047 #endif |
|
1048 |
|
1049 png_free(png_ptr, png_ptr->chunkdata); |
|
1050 png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1); |
|
1051 slength = (png_size_t)length; |
|
1052 png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); |
|
1053 |
|
1054 if (png_crc_finish(png_ptr, skip)) |
|
1055 { |
|
1056 png_free(png_ptr, png_ptr->chunkdata); |
|
1057 png_ptr->chunkdata = NULL; |
|
1058 return; |
|
1059 } |
|
1060 |
|
1061 png_ptr->chunkdata[slength] = 0x00; |
|
1062 |
|
1063 for (profile = png_ptr->chunkdata; *profile; profile++) |
|
1064 /* empty loop to find end of name */ ; |
|
1065 |
|
1066 ++profile; |
|
1067 |
|
1068 /* there should be at least one zero (the compression type byte) |
|
1069 following the separator, and we should be on it */ |
|
1070 if ( profile >= png_ptr->chunkdata + slength - 1) |
|
1071 { |
|
1072 png_free(png_ptr, png_ptr->chunkdata); |
|
1073 png_ptr->chunkdata = NULL; |
|
1074 png_warning(png_ptr, "Malformed iCCP chunk"); |
|
1075 return; |
|
1076 } |
|
1077 |
|
1078 /* compression_type should always be zero */ |
|
1079 compression_type = *profile++; |
|
1080 if (compression_type) |
|
1081 { |
|
1082 png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk"); |
|
1083 compression_type = 0x00; /* Reset it to zero (libpng-1.0.6 through 1.0.8 |
|
1084 wrote nonzero) */ |
|
1085 } |
|
1086 |
|
1087 prefix_length = profile - png_ptr->chunkdata; |
|
1088 png_decompress_chunk(png_ptr, compression_type, |
|
1089 slength, prefix_length, &data_length); |
|
1090 |
|
1091 profile_length = data_length - prefix_length; |
|
1092 |
|
1093 if ( prefix_length > data_length || profile_length < 4) |
|
1094 { |
|
1095 png_free(png_ptr, png_ptr->chunkdata); |
|
1096 png_ptr->chunkdata = NULL; |
|
1097 png_warning(png_ptr, "Profile size field missing from iCCP chunk"); |
|
1098 return; |
|
1099 } |
|
1100 |
|
1101 /* Check the profile_size recorded in the first 32 bits of the ICC profile */ |
|
1102 pC = (png_bytep)(png_ptr->chunkdata + prefix_length); |
|
1103 profile_size = ((*(pC ))<<24) | |
|
1104 ((*(pC + 1))<<16) | |
|
1105 ((*(pC + 2))<< 8) | |
|
1106 ((*(pC + 3)) ); |
|
1107 |
|
1108 if (profile_size < profile_length) |
|
1109 profile_length = profile_size; |
|
1110 |
|
1111 if (profile_size > profile_length) |
|
1112 { |
|
1113 png_free(png_ptr, png_ptr->chunkdata); |
|
1114 png_ptr->chunkdata = NULL; |
|
1115 png_warning(png_ptr, "Ignoring truncated iCCP profile."); |
|
1116 return; |
|
1117 } |
|
1118 |
|
1119 png_set_iCCP(png_ptr, info_ptr, png_ptr->chunkdata, |
|
1120 compression_type, png_ptr->chunkdata + prefix_length, profile_length); |
|
1121 png_free(png_ptr, png_ptr->chunkdata); |
|
1122 png_ptr->chunkdata = NULL; |
|
1123 } |
|
1124 #endif /* PNG_READ_iCCP_SUPPORTED */ |
|
1125 |
|
1126 #if defined(PNG_READ_sPLT_SUPPORTED) |
|
1127 void /* PRIVATE */ |
|
1128 png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1129 /* Note: this does not properly handle chunks that are > 64K under DOS */ |
|
1130 { |
|
1131 png_bytep entry_start; |
|
1132 png_sPLT_t new_palette; |
|
1133 #ifdef PNG_NO_POINTER_INDEXING |
|
1134 png_sPLT_entryp pp; |
|
1135 #endif |
|
1136 int data_length, entry_size, i; |
|
1137 png_uint_32 skip = 0; |
|
1138 png_size_t slength; |
|
1139 |
|
1140 png_debug(1, "in png_handle_sPLT\n"); |
|
1141 |
|
1142 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1143 png_error(png_ptr, "Missing IHDR before sPLT"); |
|
1144 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1145 { |
|
1146 png_warning(png_ptr, "Invalid sPLT after IDAT"); |
|
1147 png_crc_finish(png_ptr, length); |
|
1148 return; |
|
1149 } |
|
1150 |
|
1151 #ifdef PNG_MAX_MALLOC_64K |
|
1152 if (length > (png_uint_32)65535L) |
|
1153 { |
|
1154 png_warning(png_ptr, "sPLT chunk too large to fit in memory"); |
|
1155 skip = length - (png_uint_32)65535L; |
|
1156 length = (png_uint_32)65535L; |
|
1157 } |
|
1158 #endif |
|
1159 |
|
1160 png_free(png_ptr, png_ptr->chunkdata); |
|
1161 png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1); |
|
1162 slength = (png_size_t)length; |
|
1163 png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); |
|
1164 |
|
1165 if (png_crc_finish(png_ptr, skip)) |
|
1166 { |
|
1167 png_free(png_ptr, png_ptr->chunkdata); |
|
1168 png_ptr->chunkdata = NULL; |
|
1169 return; |
|
1170 } |
|
1171 |
|
1172 png_ptr->chunkdata[slength] = 0x00; |
|
1173 |
|
1174 for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start; entry_start++) |
|
1175 /* empty loop to find end of name */ ; |
|
1176 ++entry_start; |
|
1177 |
|
1178 /* a sample depth should follow the separator, and we should be on it */ |
|
1179 if (entry_start > (png_bytep)png_ptr->chunkdata + slength - 2) |
|
1180 { |
|
1181 png_free(png_ptr, png_ptr->chunkdata); |
|
1182 png_ptr->chunkdata = NULL; |
|
1183 png_warning(png_ptr, "malformed sPLT chunk"); |
|
1184 return; |
|
1185 } |
|
1186 |
|
1187 new_palette.depth = *entry_start++; |
|
1188 entry_size = (new_palette.depth == 8 ? 6 : 10); |
|
1189 data_length = (slength - (entry_start - (png_bytep)png_ptr->chunkdata)); |
|
1190 |
|
1191 /* integrity-check the data length */ |
|
1192 if (data_length % entry_size) |
|
1193 { |
|
1194 png_free(png_ptr, png_ptr->chunkdata); |
|
1195 png_ptr->chunkdata = NULL; |
|
1196 png_warning(png_ptr, "sPLT chunk has bad length"); |
|
1197 return; |
|
1198 } |
|
1199 |
|
1200 new_palette.nentries = (png_int_32) ( data_length / entry_size); |
|
1201 if ((png_uint_32) new_palette.nentries > |
|
1202 (png_uint_32) (PNG_SIZE_MAX / png_sizeof(png_sPLT_entry))) |
|
1203 { |
|
1204 png_warning(png_ptr, "sPLT chunk too long"); |
|
1205 return; |
|
1206 } |
|
1207 new_palette.entries = (png_sPLT_entryp)png_malloc_warn( |
|
1208 png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry)); |
|
1209 if (new_palette.entries == NULL) |
|
1210 { |
|
1211 png_warning(png_ptr, "sPLT chunk requires too much memory"); |
|
1212 return; |
|
1213 } |
|
1214 |
|
1215 #ifndef PNG_NO_POINTER_INDEXING |
|
1216 for (i = 0; i < new_palette.nentries; i++) |
|
1217 { |
|
1218 png_sPLT_entryp pp = new_palette.entries + i; |
|
1219 |
|
1220 if (new_palette.depth == 8) |
|
1221 { |
|
1222 pp->red = *entry_start++; |
|
1223 pp->green = *entry_start++; |
|
1224 pp->blue = *entry_start++; |
|
1225 pp->alpha = *entry_start++; |
|
1226 } |
|
1227 else |
|
1228 { |
|
1229 pp->red = png_get_uint_16(entry_start); entry_start += 2; |
|
1230 pp->green = png_get_uint_16(entry_start); entry_start += 2; |
|
1231 pp->blue = png_get_uint_16(entry_start); entry_start += 2; |
|
1232 pp->alpha = png_get_uint_16(entry_start); entry_start += 2; |
|
1233 } |
|
1234 pp->frequency = png_get_uint_16(entry_start); entry_start += 2; |
|
1235 } |
|
1236 #else |
|
1237 pp = new_palette.entries; |
|
1238 for (i = 0; i < new_palette.nentries; i++) |
|
1239 { |
|
1240 |
|
1241 if (new_palette.depth == 8) |
|
1242 { |
|
1243 pp[i].red = *entry_start++; |
|
1244 pp[i].green = *entry_start++; |
|
1245 pp[i].blue = *entry_start++; |
|
1246 pp[i].alpha = *entry_start++; |
|
1247 } |
|
1248 else |
|
1249 { |
|
1250 pp[i].red = png_get_uint_16(entry_start); entry_start += 2; |
|
1251 pp[i].green = png_get_uint_16(entry_start); entry_start += 2; |
|
1252 pp[i].blue = png_get_uint_16(entry_start); entry_start += 2; |
|
1253 pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2; |
|
1254 } |
|
1255 pp->frequency = png_get_uint_16(entry_start); entry_start += 2; |
|
1256 } |
|
1257 #endif |
|
1258 |
|
1259 /* discard all chunk data except the name and stash that */ |
|
1260 new_palette.name = png_ptr->chunkdata; |
|
1261 |
|
1262 png_set_sPLT(png_ptr, info_ptr, &new_palette, 1); |
|
1263 |
|
1264 png_free(png_ptr, png_ptr->chunkdata); |
|
1265 png_ptr->chunkdata = NULL; |
|
1266 png_free(png_ptr, new_palette.entries); |
|
1267 } |
|
1268 #endif /* PNG_READ_sPLT_SUPPORTED */ |
|
1269 |
|
1270 #if defined(PNG_READ_tRNS_SUPPORTED) |
|
1271 void /* PRIVATE */ |
|
1272 png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1273 { |
|
1274 png_byte readbuf[PNG_MAX_PALETTE_LENGTH]; |
|
1275 |
|
1276 png_debug(1, "in png_handle_tRNS\n"); |
|
1277 |
|
1278 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1279 png_error(png_ptr, "Missing IHDR before tRNS"); |
|
1280 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1281 { |
|
1282 png_warning(png_ptr, "Invalid tRNS after IDAT"); |
|
1283 png_crc_finish(png_ptr, length); |
|
1284 return; |
|
1285 } |
|
1286 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS)) |
|
1287 { |
|
1288 png_warning(png_ptr, "Duplicate tRNS chunk"); |
|
1289 png_crc_finish(png_ptr, length); |
|
1290 return; |
|
1291 } |
|
1292 |
|
1293 if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) |
|
1294 { |
|
1295 png_byte buf[2]; |
|
1296 |
|
1297 if (length != 2) |
|
1298 { |
|
1299 png_warning(png_ptr, "Incorrect tRNS chunk length"); |
|
1300 png_crc_finish(png_ptr, length); |
|
1301 return; |
|
1302 } |
|
1303 |
|
1304 png_crc_read(png_ptr, buf, 2); |
|
1305 png_ptr->num_trans = 1; |
|
1306 png_ptr->trans_values.gray = png_get_uint_16(buf); |
|
1307 } |
|
1308 else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) |
|
1309 { |
|
1310 png_byte buf[6]; |
|
1311 |
|
1312 if (length != 6) |
|
1313 { |
|
1314 png_warning(png_ptr, "Incorrect tRNS chunk length"); |
|
1315 png_crc_finish(png_ptr, length); |
|
1316 return; |
|
1317 } |
|
1318 png_crc_read(png_ptr, buf, (png_size_t)length); |
|
1319 png_ptr->num_trans = 1; |
|
1320 png_ptr->trans_values.red = png_get_uint_16(buf); |
|
1321 png_ptr->trans_values.green = png_get_uint_16(buf + 2); |
|
1322 png_ptr->trans_values.blue = png_get_uint_16(buf + 4); |
|
1323 } |
|
1324 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
1325 { |
|
1326 if (!(png_ptr->mode & PNG_HAVE_PLTE)) |
|
1327 { |
|
1328 /* Should be an error, but we can cope with it. */ |
|
1329 png_warning(png_ptr, "Missing PLTE before tRNS"); |
|
1330 } |
|
1331 if (length > (png_uint_32)png_ptr->num_palette || |
|
1332 length > PNG_MAX_PALETTE_LENGTH) |
|
1333 { |
|
1334 png_warning(png_ptr, "Incorrect tRNS chunk length"); |
|
1335 png_crc_finish(png_ptr, length); |
|
1336 return; |
|
1337 } |
|
1338 if (length == 0) |
|
1339 { |
|
1340 png_warning(png_ptr, "Zero length tRNS chunk"); |
|
1341 png_crc_finish(png_ptr, length); |
|
1342 return; |
|
1343 } |
|
1344 png_crc_read(png_ptr, readbuf, (png_size_t)length); |
|
1345 png_ptr->num_trans = (png_uint_16)length; |
|
1346 } |
|
1347 else |
|
1348 { |
|
1349 png_warning(png_ptr, "tRNS chunk not allowed with alpha channel"); |
|
1350 png_crc_finish(png_ptr, length); |
|
1351 return; |
|
1352 } |
|
1353 |
|
1354 if (png_crc_finish(png_ptr, 0)) |
|
1355 { |
|
1356 png_ptr->num_trans = 0; |
|
1357 return; |
|
1358 } |
|
1359 |
|
1360 png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans, |
|
1361 &(png_ptr->trans_values)); |
|
1362 } |
|
1363 #endif |
|
1364 |
|
1365 #if defined(PNG_READ_bKGD_SUPPORTED) |
|
1366 void /* PRIVATE */ |
|
1367 png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1368 { |
|
1369 png_size_t truelen; |
|
1370 png_byte buf[6]; |
|
1371 |
|
1372 png_debug(1, "in png_handle_bKGD\n"); |
|
1373 |
|
1374 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1375 png_error(png_ptr, "Missing IHDR before bKGD"); |
|
1376 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1377 { |
|
1378 png_warning(png_ptr, "Invalid bKGD after IDAT"); |
|
1379 png_crc_finish(png_ptr, length); |
|
1380 return; |
|
1381 } |
|
1382 else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE && |
|
1383 !(png_ptr->mode & PNG_HAVE_PLTE)) |
|
1384 { |
|
1385 png_warning(png_ptr, "Missing PLTE before bKGD"); |
|
1386 png_crc_finish(png_ptr, length); |
|
1387 return; |
|
1388 } |
|
1389 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)) |
|
1390 { |
|
1391 png_warning(png_ptr, "Duplicate bKGD chunk"); |
|
1392 png_crc_finish(png_ptr, length); |
|
1393 return; |
|
1394 } |
|
1395 |
|
1396 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
1397 truelen = 1; |
|
1398 else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR) |
|
1399 truelen = 6; |
|
1400 else |
|
1401 truelen = 2; |
|
1402 |
|
1403 if (length != truelen) |
|
1404 { |
|
1405 png_warning(png_ptr, "Incorrect bKGD chunk length"); |
|
1406 png_crc_finish(png_ptr, length); |
|
1407 return; |
|
1408 } |
|
1409 |
|
1410 png_crc_read(png_ptr, buf, truelen); |
|
1411 if (png_crc_finish(png_ptr, 0)) |
|
1412 return; |
|
1413 |
|
1414 /* We convert the index value into RGB components so that we can allow |
|
1415 * arbitrary RGB values for background when we have transparency, and |
|
1416 * so it is easy to determine the RGB values of the background color |
|
1417 * from the info_ptr struct. */ |
|
1418 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
1419 { |
|
1420 png_ptr->background.index = buf[0]; |
|
1421 if (info_ptr && info_ptr->num_palette) |
|
1422 { |
|
1423 if (buf[0] > info_ptr->num_palette) |
|
1424 { |
|
1425 png_warning(png_ptr, "Incorrect bKGD chunk index value"); |
|
1426 return; |
|
1427 } |
|
1428 png_ptr->background.red = |
|
1429 (png_uint_16)png_ptr->palette[buf[0]].red; |
|
1430 png_ptr->background.green = |
|
1431 (png_uint_16)png_ptr->palette[buf[0]].green; |
|
1432 png_ptr->background.blue = |
|
1433 (png_uint_16)png_ptr->palette[buf[0]].blue; |
|
1434 } |
|
1435 } |
|
1436 else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */ |
|
1437 { |
|
1438 png_ptr->background.red = |
|
1439 png_ptr->background.green = |
|
1440 png_ptr->background.blue = |
|
1441 png_ptr->background.gray = png_get_uint_16(buf); |
|
1442 } |
|
1443 else |
|
1444 { |
|
1445 png_ptr->background.red = png_get_uint_16(buf); |
|
1446 png_ptr->background.green = png_get_uint_16(buf + 2); |
|
1447 png_ptr->background.blue = png_get_uint_16(buf + 4); |
|
1448 } |
|
1449 |
|
1450 png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background)); |
|
1451 } |
|
1452 #endif |
|
1453 |
|
1454 #if defined(PNG_READ_hIST_SUPPORTED) |
|
1455 void /* PRIVATE */ |
|
1456 png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1457 { |
|
1458 unsigned int num, i; |
|
1459 png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH]; |
|
1460 |
|
1461 png_debug(1, "in png_handle_hIST\n"); |
|
1462 |
|
1463 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1464 png_error(png_ptr, "Missing IHDR before hIST"); |
|
1465 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1466 { |
|
1467 png_warning(png_ptr, "Invalid hIST after IDAT"); |
|
1468 png_crc_finish(png_ptr, length); |
|
1469 return; |
|
1470 } |
|
1471 else if (!(png_ptr->mode & PNG_HAVE_PLTE)) |
|
1472 { |
|
1473 png_warning(png_ptr, "Missing PLTE before hIST"); |
|
1474 png_crc_finish(png_ptr, length); |
|
1475 return; |
|
1476 } |
|
1477 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)) |
|
1478 { |
|
1479 png_warning(png_ptr, "Duplicate hIST chunk"); |
|
1480 png_crc_finish(png_ptr, length); |
|
1481 return; |
|
1482 } |
|
1483 |
|
1484 num = length / 2 ; |
|
1485 if (num != (unsigned int) png_ptr->num_palette || num > |
|
1486 (unsigned int) PNG_MAX_PALETTE_LENGTH) |
|
1487 { |
|
1488 png_warning(png_ptr, "Incorrect hIST chunk length"); |
|
1489 png_crc_finish(png_ptr, length); |
|
1490 return; |
|
1491 } |
|
1492 |
|
1493 for (i = 0; i < num; i++) |
|
1494 { |
|
1495 png_byte buf[2]; |
|
1496 |
|
1497 png_crc_read(png_ptr, buf, 2); |
|
1498 readbuf[i] = png_get_uint_16(buf); |
|
1499 } |
|
1500 |
|
1501 if (png_crc_finish(png_ptr, 0)) |
|
1502 return; |
|
1503 |
|
1504 png_set_hIST(png_ptr, info_ptr, readbuf); |
|
1505 } |
|
1506 #endif |
|
1507 |
|
1508 #if defined(PNG_READ_pHYs_SUPPORTED) |
|
1509 void /* PRIVATE */ |
|
1510 png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1511 { |
|
1512 png_byte buf[9]; |
|
1513 png_uint_32 res_x, res_y; |
|
1514 int unit_type; |
|
1515 |
|
1516 png_debug(1, "in png_handle_pHYs\n"); |
|
1517 |
|
1518 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1519 png_error(png_ptr, "Missing IHDR before pHYs"); |
|
1520 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1521 { |
|
1522 png_warning(png_ptr, "Invalid pHYs after IDAT"); |
|
1523 png_crc_finish(png_ptr, length); |
|
1524 return; |
|
1525 } |
|
1526 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)) |
|
1527 { |
|
1528 png_warning(png_ptr, "Duplicate pHYs chunk"); |
|
1529 png_crc_finish(png_ptr, length); |
|
1530 return; |
|
1531 } |
|
1532 |
|
1533 if (length != 9) |
|
1534 { |
|
1535 png_warning(png_ptr, "Incorrect pHYs chunk length"); |
|
1536 png_crc_finish(png_ptr, length); |
|
1537 return; |
|
1538 } |
|
1539 |
|
1540 png_crc_read(png_ptr, buf, 9); |
|
1541 if (png_crc_finish(png_ptr, 0)) |
|
1542 return; |
|
1543 |
|
1544 res_x = png_get_uint_32(buf); |
|
1545 res_y = png_get_uint_32(buf + 4); |
|
1546 unit_type = buf[8]; |
|
1547 png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type); |
|
1548 } |
|
1549 #endif |
|
1550 |
|
1551 #if defined(PNG_READ_oFFs_SUPPORTED) |
|
1552 void /* PRIVATE */ |
|
1553 png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1554 { |
|
1555 png_byte buf[9]; |
|
1556 png_int_32 offset_x, offset_y; |
|
1557 int unit_type; |
|
1558 |
|
1559 png_debug(1, "in png_handle_oFFs\n"); |
|
1560 |
|
1561 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1562 png_error(png_ptr, "Missing IHDR before oFFs"); |
|
1563 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1564 { |
|
1565 png_warning(png_ptr, "Invalid oFFs after IDAT"); |
|
1566 png_crc_finish(png_ptr, length); |
|
1567 return; |
|
1568 } |
|
1569 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)) |
|
1570 { |
|
1571 png_warning(png_ptr, "Duplicate oFFs chunk"); |
|
1572 png_crc_finish(png_ptr, length); |
|
1573 return; |
|
1574 } |
|
1575 |
|
1576 if (length != 9) |
|
1577 { |
|
1578 png_warning(png_ptr, "Incorrect oFFs chunk length"); |
|
1579 png_crc_finish(png_ptr, length); |
|
1580 return; |
|
1581 } |
|
1582 |
|
1583 png_crc_read(png_ptr, buf, 9); |
|
1584 if (png_crc_finish(png_ptr, 0)) |
|
1585 return; |
|
1586 |
|
1587 offset_x = png_get_int_32(buf); |
|
1588 offset_y = png_get_int_32(buf + 4); |
|
1589 unit_type = buf[8]; |
|
1590 png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type); |
|
1591 } |
|
1592 #endif |
|
1593 |
|
1594 #if defined(PNG_READ_pCAL_SUPPORTED) |
|
1595 /* read the pCAL chunk (described in the PNG Extensions document) */ |
|
1596 void /* PRIVATE */ |
|
1597 png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1598 { |
|
1599 png_int_32 X0, X1; |
|
1600 png_byte type, nparams; |
|
1601 png_charp buf, units, endptr; |
|
1602 png_charpp params; |
|
1603 png_size_t slength; |
|
1604 int i; |
|
1605 |
|
1606 png_debug(1, "in png_handle_pCAL\n"); |
|
1607 |
|
1608 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1609 png_error(png_ptr, "Missing IHDR before pCAL"); |
|
1610 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1611 { |
|
1612 png_warning(png_ptr, "Invalid pCAL after IDAT"); |
|
1613 png_crc_finish(png_ptr, length); |
|
1614 return; |
|
1615 } |
|
1616 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)) |
|
1617 { |
|
1618 png_warning(png_ptr, "Duplicate pCAL chunk"); |
|
1619 png_crc_finish(png_ptr, length); |
|
1620 return; |
|
1621 } |
|
1622 |
|
1623 png_debug1(2, "Allocating and reading pCAL chunk data (%lu bytes)\n", |
|
1624 length + 1); |
|
1625 png_free(png_ptr, png_ptr->chunkdata); |
|
1626 png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); |
|
1627 if (png_ptr->chunkdata == NULL) |
|
1628 { |
|
1629 png_warning(png_ptr, "No memory for pCAL purpose."); |
|
1630 return; |
|
1631 } |
|
1632 slength = (png_size_t)length; |
|
1633 png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); |
|
1634 |
|
1635 if (png_crc_finish(png_ptr, 0)) |
|
1636 { |
|
1637 png_free(png_ptr, png_ptr->chunkdata); |
|
1638 png_ptr->chunkdata = NULL; |
|
1639 return; |
|
1640 } |
|
1641 |
|
1642 png_ptr->chunkdata[slength] = 0x00; /* null terminate the last string */ |
|
1643 |
|
1644 png_debug(3, "Finding end of pCAL purpose string\n"); |
|
1645 for (buf = png_ptr->chunkdata; *buf; buf++) |
|
1646 /* empty loop */ ; |
|
1647 |
|
1648 endptr = png_ptr->chunkdata + slength; |
|
1649 |
|
1650 /* We need to have at least 12 bytes after the purpose string |
|
1651 in order to get the parameter information. */ |
|
1652 if (endptr <= buf + 12) |
|
1653 { |
|
1654 png_warning(png_ptr, "Invalid pCAL data"); |
|
1655 png_free(png_ptr, png_ptr->chunkdata); |
|
1656 png_ptr->chunkdata = NULL; |
|
1657 return; |
|
1658 } |
|
1659 |
|
1660 png_debug(3, "Reading pCAL X0, X1, type, nparams, and units\n"); |
|
1661 X0 = png_get_int_32((png_bytep)buf+1); |
|
1662 X1 = png_get_int_32((png_bytep)buf+5); |
|
1663 type = buf[9]; |
|
1664 nparams = buf[10]; |
|
1665 units = buf + 11; |
|
1666 |
|
1667 png_debug(3, "Checking pCAL equation type and number of parameters\n"); |
|
1668 /* Check that we have the right number of parameters for known |
|
1669 equation types. */ |
|
1670 if ((type == PNG_EQUATION_LINEAR && nparams != 2) || |
|
1671 (type == PNG_EQUATION_BASE_E && nparams != 3) || |
|
1672 (type == PNG_EQUATION_ARBITRARY && nparams != 3) || |
|
1673 (type == PNG_EQUATION_HYPERBOLIC && nparams != 4)) |
|
1674 { |
|
1675 png_warning(png_ptr, "Invalid pCAL parameters for equation type"); |
|
1676 png_free(png_ptr, png_ptr->chunkdata); |
|
1677 png_ptr->chunkdata = NULL; |
|
1678 return; |
|
1679 } |
|
1680 else if (type >= PNG_EQUATION_LAST) |
|
1681 { |
|
1682 png_warning(png_ptr, "Unrecognized equation type for pCAL chunk"); |
|
1683 } |
|
1684 |
|
1685 for (buf = units; *buf; buf++) |
|
1686 /* Empty loop to move past the units string. */ ; |
|
1687 |
|
1688 png_debug(3, "Allocating pCAL parameters array\n"); |
|
1689 params = (png_charpp)png_malloc_warn(png_ptr, |
|
1690 (png_uint_32)(nparams * png_sizeof(png_charp))) ; |
|
1691 if (params == NULL) |
|
1692 { |
|
1693 png_free(png_ptr, png_ptr->chunkdata); |
|
1694 png_ptr->chunkdata = NULL; |
|
1695 png_warning(png_ptr, "No memory for pCAL params."); |
|
1696 return; |
|
1697 } |
|
1698 |
|
1699 /* Get pointers to the start of each parameter string. */ |
|
1700 for (i = 0; i < (int)nparams; i++) |
|
1701 { |
|
1702 buf++; /* Skip the null string terminator from previous parameter. */ |
|
1703 |
|
1704 png_debug1(3, "Reading pCAL parameter %d\n", i); |
|
1705 for (params[i] = buf; buf <= endptr && *buf != 0x00; buf++) |
|
1706 /* Empty loop to move past each parameter string */ ; |
|
1707 |
|
1708 /* Make sure we haven't run out of data yet */ |
|
1709 if (buf > endptr) |
|
1710 { |
|
1711 png_warning(png_ptr, "Invalid pCAL data"); |
|
1712 png_free(png_ptr, png_ptr->chunkdata); |
|
1713 png_ptr->chunkdata = NULL; |
|
1714 png_free(png_ptr, params); |
|
1715 return; |
|
1716 } |
|
1717 } |
|
1718 |
|
1719 png_set_pCAL(png_ptr, info_ptr, png_ptr->chunkdata, X0, X1, type, nparams, |
|
1720 units, params); |
|
1721 |
|
1722 png_free(png_ptr, png_ptr->chunkdata); |
|
1723 png_ptr->chunkdata = NULL; |
|
1724 png_free(png_ptr, params); |
|
1725 } |
|
1726 #endif |
|
1727 |
|
1728 #if defined(PNG_READ_sCAL_SUPPORTED) |
|
1729 /* read the sCAL chunk */ |
|
1730 void /* PRIVATE */ |
|
1731 png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1732 { |
|
1733 png_charp ep; |
|
1734 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
1735 double width, height; |
|
1736 png_charp vp; |
|
1737 #else |
|
1738 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
1739 png_charp swidth, sheight; |
|
1740 #endif |
|
1741 #endif |
|
1742 png_size_t slength; |
|
1743 |
|
1744 png_debug(1, "in png_handle_sCAL\n"); |
|
1745 |
|
1746 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1747 png_error(png_ptr, "Missing IHDR before sCAL"); |
|
1748 else if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1749 { |
|
1750 png_warning(png_ptr, "Invalid sCAL after IDAT"); |
|
1751 png_crc_finish(png_ptr, length); |
|
1752 return; |
|
1753 } |
|
1754 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL)) |
|
1755 { |
|
1756 png_warning(png_ptr, "Duplicate sCAL chunk"); |
|
1757 png_crc_finish(png_ptr, length); |
|
1758 return; |
|
1759 } |
|
1760 |
|
1761 png_debug1(2, "Allocating and reading sCAL chunk data (%lu bytes)\n", |
|
1762 length + 1); |
|
1763 png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); |
|
1764 if (png_ptr->chunkdata == NULL) |
|
1765 { |
|
1766 png_warning(png_ptr, "Out of memory while processing sCAL chunk"); |
|
1767 return; |
|
1768 } |
|
1769 slength = (png_size_t)length; |
|
1770 png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); |
|
1771 |
|
1772 if (png_crc_finish(png_ptr, 0)) |
|
1773 { |
|
1774 png_free(png_ptr, png_ptr->chunkdata); |
|
1775 png_ptr->chunkdata = NULL; |
|
1776 return; |
|
1777 } |
|
1778 |
|
1779 png_ptr->chunkdata[slength] = 0x00; /* null terminate the last string */ |
|
1780 |
|
1781 ep = png_ptr->chunkdata + 1; /* skip unit byte */ |
|
1782 |
|
1783 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
1784 width = png_strtod(png_ptr, ep, &vp); |
|
1785 if (*vp) |
|
1786 { |
|
1787 png_warning(png_ptr, "malformed width string in sCAL chunk"); |
|
1788 return; |
|
1789 } |
|
1790 #else |
|
1791 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
1792 swidth = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1); |
|
1793 if (swidth == NULL) |
|
1794 { |
|
1795 png_warning(png_ptr, "Out of memory while processing sCAL chunk width"); |
|
1796 return; |
|
1797 } |
|
1798 png_memcpy(swidth, ep, (png_size_t)png_strlen(ep)); |
|
1799 #endif |
|
1800 #endif |
|
1801 |
|
1802 for (ep = png_ptr->chunkdata; *ep; ep++) |
|
1803 /* empty loop */ ; |
|
1804 ep++; |
|
1805 |
|
1806 if (png_ptr->chunkdata + slength < ep) |
|
1807 { |
|
1808 png_warning(png_ptr, "Truncated sCAL chunk"); |
|
1809 #if defined(PNG_FIXED_POINT_SUPPORTED) && \ |
|
1810 !defined(PNG_FLOATING_POINT_SUPPORTED) |
|
1811 png_free(png_ptr, swidth); |
|
1812 #endif |
|
1813 png_free(png_ptr, png_ptr->chunkdata); |
|
1814 png_ptr->chunkdata = NULL; |
|
1815 return; |
|
1816 } |
|
1817 |
|
1818 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
1819 height = png_strtod(png_ptr, ep, &vp); |
|
1820 if (*vp) |
|
1821 { |
|
1822 png_warning(png_ptr, "malformed height string in sCAL chunk"); |
|
1823 return; |
|
1824 } |
|
1825 #else |
|
1826 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
1827 sheight = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1); |
|
1828 if (sheight == NULL) |
|
1829 { |
|
1830 png_warning(png_ptr, "Out of memory while processing sCAL chunk height"); |
|
1831 return; |
|
1832 } |
|
1833 png_memcpy(sheight, ep, (png_size_t)png_strlen(ep)); |
|
1834 #endif |
|
1835 #endif |
|
1836 |
|
1837 if (png_ptr->chunkdata + slength < ep |
|
1838 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
1839 || width <= 0. || height <= 0. |
|
1840 #endif |
|
1841 ) |
|
1842 { |
|
1843 png_warning(png_ptr, "Invalid sCAL data"); |
|
1844 png_free(png_ptr, png_ptr->chunkdata); |
|
1845 png_ptr->chunkdata = NULL; |
|
1846 #if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED) |
|
1847 png_free(png_ptr, swidth); |
|
1848 png_free(png_ptr, sheight); |
|
1849 #endif |
|
1850 return; |
|
1851 } |
|
1852 |
|
1853 |
|
1854 #ifdef PNG_FLOATING_POINT_SUPPORTED |
|
1855 png_set_sCAL(png_ptr, info_ptr, png_ptr->chunkdata[0], width, height); |
|
1856 #else |
|
1857 #ifdef PNG_FIXED_POINT_SUPPORTED |
|
1858 png_set_sCAL_s(png_ptr, info_ptr, png_ptr->chunkdata[0], swidth, sheight); |
|
1859 #endif |
|
1860 #endif |
|
1861 |
|
1862 png_free(png_ptr, png_ptr->chunkdata); |
|
1863 png_ptr->chunkdata = NULL; |
|
1864 #if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED) |
|
1865 png_free(png_ptr, swidth); |
|
1866 png_free(png_ptr, sheight); |
|
1867 #endif |
|
1868 } |
|
1869 #endif |
|
1870 |
|
1871 #if defined(PNG_READ_tIME_SUPPORTED) |
|
1872 void /* PRIVATE */ |
|
1873 png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1874 { |
|
1875 png_byte buf[7]; |
|
1876 png_time mod_time; |
|
1877 |
|
1878 png_debug(1, "in png_handle_tIME\n"); |
|
1879 |
|
1880 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1881 png_error(png_ptr, "Out of place tIME chunk"); |
|
1882 else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)) |
|
1883 { |
|
1884 png_warning(png_ptr, "Duplicate tIME chunk"); |
|
1885 png_crc_finish(png_ptr, length); |
|
1886 return; |
|
1887 } |
|
1888 |
|
1889 if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1890 png_ptr->mode |= PNG_AFTER_IDAT; |
|
1891 |
|
1892 if (length != 7) |
|
1893 { |
|
1894 png_warning(png_ptr, "Incorrect tIME chunk length"); |
|
1895 png_crc_finish(png_ptr, length); |
|
1896 return; |
|
1897 } |
|
1898 |
|
1899 png_crc_read(png_ptr, buf, 7); |
|
1900 if (png_crc_finish(png_ptr, 0)) |
|
1901 return; |
|
1902 |
|
1903 mod_time.second = buf[6]; |
|
1904 mod_time.minute = buf[5]; |
|
1905 mod_time.hour = buf[4]; |
|
1906 mod_time.day = buf[3]; |
|
1907 mod_time.month = buf[2]; |
|
1908 mod_time.year = png_get_uint_16(buf); |
|
1909 |
|
1910 png_set_tIME(png_ptr, info_ptr, &mod_time); |
|
1911 } |
|
1912 #endif |
|
1913 |
|
1914 #if defined(PNG_READ_tEXt_SUPPORTED) |
|
1915 /* Note: this does not properly handle chunks that are > 64K under DOS */ |
|
1916 void /* PRIVATE */ |
|
1917 png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1918 { |
|
1919 png_textp text_ptr; |
|
1920 png_charp key; |
|
1921 png_charp text; |
|
1922 png_uint_32 skip = 0; |
|
1923 png_size_t slength; |
|
1924 int ret; |
|
1925 |
|
1926 png_debug(1, "in png_handle_tEXt\n"); |
|
1927 |
|
1928 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
1929 png_error(png_ptr, "Missing IHDR before tEXt"); |
|
1930 |
|
1931 if (png_ptr->mode & PNG_HAVE_IDAT) |
|
1932 png_ptr->mode |= PNG_AFTER_IDAT; |
|
1933 |
|
1934 #ifdef PNG_MAX_MALLOC_64K |
|
1935 if (length > (png_uint_32)65535L) |
|
1936 { |
|
1937 png_warning(png_ptr, "tEXt chunk too large to fit in memory"); |
|
1938 skip = length - (png_uint_32)65535L; |
|
1939 length = (png_uint_32)65535L; |
|
1940 } |
|
1941 #endif |
|
1942 |
|
1943 key = (png_charp)png_malloc_warn(png_ptr, length + 1); |
|
1944 if (key == NULL) |
|
1945 { |
|
1946 png_warning(png_ptr, "No memory to process text chunk."); |
|
1947 return; |
|
1948 } |
|
1949 slength = (png_size_t)length; |
|
1950 png_crc_read(png_ptr, (png_bytep)key, slength); |
|
1951 |
|
1952 if (png_crc_finish(png_ptr, skip)) |
|
1953 { |
|
1954 png_free(png_ptr, key); |
|
1955 return; |
|
1956 } |
|
1957 |
|
1958 key[slength] = 0x00; |
|
1959 |
|
1960 for (text = key; *text; text++) |
|
1961 /* empty loop to find end of key */ ; |
|
1962 |
|
1963 if (text != key + slength) |
|
1964 text++; |
|
1965 |
|
1966 text_ptr = (png_textp)png_malloc_warn(png_ptr, |
|
1967 (png_uint_32)png_sizeof(png_text)); |
|
1968 if (text_ptr == NULL) |
|
1969 { |
|
1970 png_warning(png_ptr, "Not enough memory to process text chunk."); |
|
1971 png_free(png_ptr, key); |
|
1972 return; |
|
1973 } |
|
1974 text_ptr->compression = PNG_TEXT_COMPRESSION_NONE; |
|
1975 text_ptr->key = key; |
|
1976 #ifdef PNG_iTXt_SUPPORTED |
|
1977 text_ptr->lang = NULL; |
|
1978 text_ptr->lang_key = NULL; |
|
1979 text_ptr->itxt_length = 0; |
|
1980 #endif |
|
1981 text_ptr->text = text; |
|
1982 text_ptr->text_length = png_strlen(text); |
|
1983 |
|
1984 ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); |
|
1985 |
|
1986 png_free(png_ptr, key); |
|
1987 png_free(png_ptr, text_ptr); |
|
1988 if (ret) |
|
1989 png_warning(png_ptr, "Insufficient memory to process text chunk."); |
|
1990 } |
|
1991 #endif |
|
1992 |
|
1993 #if defined(PNG_READ_zTXt_SUPPORTED) |
|
1994 /* note: this does not correctly handle chunks that are > 64K under DOS */ |
|
1995 void /* PRIVATE */ |
|
1996 png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
1997 { |
|
1998 png_textp text_ptr; |
|
1999 png_charp text; |
|
2000 int comp_type; |
|
2001 int ret; |
|
2002 png_size_t slength, prefix_len, data_len; |
|
2003 |
|
2004 png_debug(1, "in png_handle_zTXt\n"); |
|
2005 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
2006 png_error(png_ptr, "Missing IHDR before zTXt"); |
|
2007 |
|
2008 if (png_ptr->mode & PNG_HAVE_IDAT) |
|
2009 png_ptr->mode |= PNG_AFTER_IDAT; |
|
2010 |
|
2011 #ifdef PNG_MAX_MALLOC_64K |
|
2012 /* We will no doubt have problems with chunks even half this size, but |
|
2013 there is no hard and fast rule to tell us where to stop. */ |
|
2014 if (length > (png_uint_32)65535L) |
|
2015 { |
|
2016 png_warning(png_ptr, "zTXt chunk too large to fit in memory"); |
|
2017 png_crc_finish(png_ptr, length); |
|
2018 return; |
|
2019 } |
|
2020 #endif |
|
2021 |
|
2022 png_free(png_ptr,png_ptr->chunkdata); |
|
2023 png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); |
|
2024 if (png_ptr->chunkdata == NULL) |
|
2025 { |
|
2026 png_warning(png_ptr, "Out of memory processing zTXt chunk."); |
|
2027 return; |
|
2028 } |
|
2029 slength = (png_size_t)length; |
|
2030 png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); |
|
2031 if (png_crc_finish(png_ptr, 0)) |
|
2032 { |
|
2033 png_free(png_ptr, png_ptr->chunkdata); |
|
2034 png_ptr->chunkdata = NULL; |
|
2035 return; |
|
2036 } |
|
2037 |
|
2038 png_ptr->chunkdata[slength] = 0x00; |
|
2039 |
|
2040 for (text = png_ptr->chunkdata; *text; text++) |
|
2041 /* empty loop */ ; |
|
2042 |
|
2043 /* zTXt must have some text after the chunkdataword */ |
|
2044 if (text >= png_ptr->chunkdata + slength - 2) |
|
2045 { |
|
2046 png_warning(png_ptr, "Truncated zTXt chunk"); |
|
2047 png_free(png_ptr, png_ptr->chunkdata); |
|
2048 png_ptr->chunkdata = NULL; |
|
2049 return; |
|
2050 } |
|
2051 else |
|
2052 { |
|
2053 comp_type = *(++text); |
|
2054 if (comp_type != PNG_TEXT_COMPRESSION_zTXt) |
|
2055 { |
|
2056 png_warning(png_ptr, "Unknown compression type in zTXt chunk"); |
|
2057 comp_type = PNG_TEXT_COMPRESSION_zTXt; |
|
2058 } |
|
2059 text++; /* skip the compression_method byte */ |
|
2060 } |
|
2061 prefix_len = text - png_ptr->chunkdata; |
|
2062 |
|
2063 png_decompress_chunk(png_ptr, comp_type, |
|
2064 (png_size_t)length, prefix_len, &data_len); |
|
2065 |
|
2066 text_ptr = (png_textp)png_malloc_warn(png_ptr, |
|
2067 (png_uint_32)png_sizeof(png_text)); |
|
2068 if (text_ptr == NULL) |
|
2069 { |
|
2070 png_warning(png_ptr, "Not enough memory to process zTXt chunk."); |
|
2071 png_free(png_ptr, png_ptr->chunkdata); |
|
2072 png_ptr->chunkdata = NULL; |
|
2073 return; |
|
2074 } |
|
2075 text_ptr->compression = comp_type; |
|
2076 text_ptr->key = png_ptr->chunkdata; |
|
2077 #ifdef PNG_iTXt_SUPPORTED |
|
2078 text_ptr->lang = NULL; |
|
2079 text_ptr->lang_key = NULL; |
|
2080 text_ptr->itxt_length = 0; |
|
2081 #endif |
|
2082 text_ptr->text = png_ptr->chunkdata + prefix_len; |
|
2083 text_ptr->text_length = data_len; |
|
2084 |
|
2085 ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); |
|
2086 |
|
2087 png_free(png_ptr, text_ptr); |
|
2088 png_free(png_ptr, png_ptr->chunkdata); |
|
2089 png_ptr->chunkdata = NULL; |
|
2090 if (ret) |
|
2091 png_error(png_ptr, "Insufficient memory to store zTXt chunk."); |
|
2092 } |
|
2093 #endif |
|
2094 |
|
2095 #if defined(PNG_READ_iTXt_SUPPORTED) |
|
2096 /* note: this does not correctly handle chunks that are > 64K under DOS */ |
|
2097 void /* PRIVATE */ |
|
2098 png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
2099 { |
|
2100 png_textp text_ptr; |
|
2101 png_charp key, lang, text, lang_key; |
|
2102 int comp_flag; |
|
2103 int comp_type = 0; |
|
2104 int ret; |
|
2105 png_size_t slength, prefix_len, data_len; |
|
2106 |
|
2107 png_debug(1, "in png_handle_iTXt\n"); |
|
2108 |
|
2109 if (!(png_ptr->mode & PNG_HAVE_IHDR)) |
|
2110 png_error(png_ptr, "Missing IHDR before iTXt"); |
|
2111 |
|
2112 if (png_ptr->mode & PNG_HAVE_IDAT) |
|
2113 png_ptr->mode |= PNG_AFTER_IDAT; |
|
2114 |
|
2115 #ifdef PNG_MAX_MALLOC_64K |
|
2116 /* We will no doubt have problems with chunks even half this size, but |
|
2117 there is no hard and fast rule to tell us where to stop. */ |
|
2118 if (length > (png_uint_32)65535L) |
|
2119 { |
|
2120 png_warning(png_ptr, "iTXt chunk too large to fit in memory"); |
|
2121 png_crc_finish(png_ptr, length); |
|
2122 return; |
|
2123 } |
|
2124 #endif |
|
2125 |
|
2126 png_free(png_ptr, png_ptr->chunkdata); |
|
2127 png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1); |
|
2128 if (png_ptr->chunkdata == NULL) |
|
2129 { |
|
2130 png_warning(png_ptr, "No memory to process iTXt chunk."); |
|
2131 return; |
|
2132 } |
|
2133 slength = (png_size_t)length; |
|
2134 png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength); |
|
2135 if (png_crc_finish(png_ptr, 0)) |
|
2136 { |
|
2137 png_free(png_ptr, png_ptr->chunkdata); |
|
2138 png_ptr->chunkdata = NULL; |
|
2139 return; |
|
2140 } |
|
2141 |
|
2142 png_ptr->chunkdata[slength] = 0x00; |
|
2143 |
|
2144 for (lang = png_ptr->chunkdata; *lang; lang++) |
|
2145 /* empty loop */ ; |
|
2146 lang++; /* skip NUL separator */ |
|
2147 |
|
2148 /* iTXt must have a language tag (possibly empty), two compression bytes, |
|
2149 translated keyword (possibly empty), and possibly some text after the |
|
2150 keyword */ |
|
2151 |
|
2152 if (lang >= png_ptr->chunkdata + slength - 3) |
|
2153 { |
|
2154 png_warning(png_ptr, "Truncated iTXt chunk"); |
|
2155 png_free(png_ptr, png_ptr->chunkdata); |
|
2156 png_ptr->chunkdata = NULL; |
|
2157 return; |
|
2158 } |
|
2159 else |
|
2160 { |
|
2161 comp_flag = *lang++; |
|
2162 comp_type = *lang++; |
|
2163 } |
|
2164 |
|
2165 for (lang_key = lang; *lang_key; lang_key++) |
|
2166 /* empty loop */ ; |
|
2167 lang_key++; /* skip NUL separator */ |
|
2168 |
|
2169 if (lang_key >= png_ptr->chunkdata + slength) |
|
2170 { |
|
2171 png_warning(png_ptr, "Truncated iTXt chunk"); |
|
2172 png_free(png_ptr, png_ptr->chunkdata); |
|
2173 png_ptr->chunkdata = NULL; |
|
2174 return; |
|
2175 } |
|
2176 |
|
2177 for (text = lang_key; *text; text++) |
|
2178 /* empty loop */ ; |
|
2179 text++; /* skip NUL separator */ |
|
2180 if (text >= png_ptr->chunkdata + slength) |
|
2181 { |
|
2182 png_warning(png_ptr, "Malformed iTXt chunk"); |
|
2183 png_free(png_ptr, png_ptr->chunkdata); |
|
2184 png_ptr->chunkdata = NULL; |
|
2185 return; |
|
2186 } |
|
2187 |
|
2188 prefix_len = text - png_ptr->chunkdata; |
|
2189 |
|
2190 key=png_ptr->chunkdata; |
|
2191 if (comp_flag) |
|
2192 png_decompress_chunk(png_ptr, comp_type, |
|
2193 (size_t)length, prefix_len, &data_len); |
|
2194 else |
|
2195 data_len = png_strlen(png_ptr->chunkdata + prefix_len); |
|
2196 text_ptr = (png_textp)png_malloc_warn(png_ptr, |
|
2197 (png_uint_32)png_sizeof(png_text)); |
|
2198 if (text_ptr == NULL) |
|
2199 { |
|
2200 png_warning(png_ptr, "Not enough memory to process iTXt chunk."); |
|
2201 png_free(png_ptr, png_ptr->chunkdata); |
|
2202 png_ptr->chunkdata = NULL; |
|
2203 return; |
|
2204 } |
|
2205 text_ptr->compression = (int)comp_flag + 1; |
|
2206 text_ptr->lang_key = png_ptr->chunkdata + (lang_key - key); |
|
2207 text_ptr->lang = png_ptr->chunkdata + (lang - key); |
|
2208 text_ptr->itxt_length = data_len; |
|
2209 text_ptr->text_length = 0; |
|
2210 text_ptr->key = png_ptr->chunkdata; |
|
2211 text_ptr->text = png_ptr->chunkdata + prefix_len; |
|
2212 |
|
2213 ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1); |
|
2214 |
|
2215 png_free(png_ptr, text_ptr); |
|
2216 png_free(png_ptr, png_ptr->chunkdata); |
|
2217 png_ptr->chunkdata = NULL; |
|
2218 if (ret) |
|
2219 png_error(png_ptr, "Insufficient memory to store iTXt chunk."); |
|
2220 } |
|
2221 #endif |
|
2222 |
|
2223 /* This function is called when we haven't found a handler for a |
|
2224 chunk. If there isn't a problem with the chunk itself (ie bad |
|
2225 chunk name, CRC, or a critical chunk), the chunk is silently ignored |
|
2226 -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which |
|
2227 case it will be saved away to be written out later. */ |
|
2228 void /* PRIVATE */ |
|
2229 png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length) |
|
2230 { |
|
2231 png_uint_32 skip = 0; |
|
2232 |
|
2233 png_debug(1, "in png_handle_unknown\n"); |
|
2234 |
|
2235 if (png_ptr->mode & PNG_HAVE_IDAT) |
|
2236 { |
|
2237 #ifdef PNG_USE_LOCAL_ARRAYS |
|
2238 PNG_CONST PNG_IDAT; |
|
2239 #endif |
|
2240 if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) /* not an IDAT */ |
|
2241 png_ptr->mode |= PNG_AFTER_IDAT; |
|
2242 } |
|
2243 |
|
2244 if (!(png_ptr->chunk_name[0] & 0x20)) |
|
2245 { |
|
2246 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) |
|
2247 if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) != |
|
2248 PNG_HANDLE_CHUNK_ALWAYS |
|
2249 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED) |
|
2250 && png_ptr->read_user_chunk_fn == NULL |
|
2251 #endif |
|
2252 ) |
|
2253 #endif |
|
2254 png_chunk_error(png_ptr, "unknown critical chunk"); |
|
2255 } |
|
2256 |
|
2257 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) |
|
2258 if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) || |
|
2259 (png_ptr->read_user_chunk_fn != NULL)) |
|
2260 { |
|
2261 #ifdef PNG_MAX_MALLOC_64K |
|
2262 if (length > (png_uint_32)65535L) |
|
2263 { |
|
2264 png_warning(png_ptr, "unknown chunk too large to fit in memory"); |
|
2265 skip = length - (png_uint_32)65535L; |
|
2266 length = (png_uint_32)65535L; |
|
2267 } |
|
2268 #endif |
|
2269 png_memcpy((png_charp)png_ptr->unknown_chunk.name, |
|
2270 (png_charp)png_ptr->chunk_name, |
|
2271 png_sizeof(png_ptr->unknown_chunk.name)); |
|
2272 png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name)-1] = '\0'; |
|
2273 png_ptr->unknown_chunk.size = (png_size_t)length; |
|
2274 if (length == 0) |
|
2275 png_ptr->unknown_chunk.data = NULL; |
|
2276 else |
|
2277 { |
|
2278 png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length); |
|
2279 png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length); |
|
2280 } |
|
2281 #if defined(PNG_READ_USER_CHUNKS_SUPPORTED) |
|
2282 if (png_ptr->read_user_chunk_fn != NULL) |
|
2283 { |
|
2284 /* callback to user unknown chunk handler */ |
|
2285 int ret; |
|
2286 ret = (*(png_ptr->read_user_chunk_fn)) |
|
2287 (png_ptr, &png_ptr->unknown_chunk); |
|
2288 if (ret < 0) |
|
2289 png_chunk_error(png_ptr, "error in user chunk"); |
|
2290 if (ret == 0) |
|
2291 { |
|
2292 if (!(png_ptr->chunk_name[0] & 0x20)) |
|
2293 if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) != |
|
2294 PNG_HANDLE_CHUNK_ALWAYS) |
|
2295 png_chunk_error(png_ptr, "unknown critical chunk"); |
|
2296 png_set_unknown_chunks(png_ptr, info_ptr, |
|
2297 &png_ptr->unknown_chunk, 1); |
|
2298 } |
|
2299 } |
|
2300 else |
|
2301 #endif |
|
2302 png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1); |
|
2303 png_free(png_ptr, png_ptr->unknown_chunk.data); |
|
2304 png_ptr->unknown_chunk.data = NULL; |
|
2305 } |
|
2306 else |
|
2307 #endif |
|
2308 skip = length; |
|
2309 |
|
2310 png_crc_finish(png_ptr, skip); |
|
2311 |
|
2312 #if !defined(PNG_READ_USER_CHUNKS_SUPPORTED) |
|
2313 info_ptr = info_ptr; /* quiet compiler warnings about unused info_ptr */ |
|
2314 #endif |
|
2315 } |
|
2316 |
|
2317 /* This function is called to verify that a chunk name is valid. |
|
2318 This function can't have the "critical chunk check" incorporated |
|
2319 into it, since in the future we will need to be able to call user |
|
2320 functions to handle unknown critical chunks after we check that |
|
2321 the chunk name itself is valid. */ |
|
2322 |
|
2323 #define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) |
|
2324 |
|
2325 void /* PRIVATE */ |
|
2326 png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name) |
|
2327 { |
|
2328 png_debug(1, "in png_check_chunk_name\n"); |
|
2329 if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) || |
|
2330 isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3])) |
|
2331 { |
|
2332 png_chunk_error(png_ptr, "invalid chunk type"); |
|
2333 } |
|
2334 } |
|
2335 |
|
2336 /* Combines the row recently read in with the existing pixels in the |
|
2337 row. This routine takes care of alpha and transparency if requested. |
|
2338 This routine also handles the two methods of progressive display |
|
2339 of interlaced images, depending on the mask value. |
|
2340 The mask value describes which pixels are to be combined with |
|
2341 the row. The pattern always repeats every 8 pixels, so just 8 |
|
2342 bits are needed. A one indicates the pixel is to be combined, |
|
2343 a zero indicates the pixel is to be skipped. This is in addition |
|
2344 to any alpha or transparency value associated with the pixel. If |
|
2345 you want all pixels to be combined, pass 0xff (255) in mask. */ |
|
2346 |
|
2347 void /* PRIVATE */ |
|
2348 png_combine_row(png_structp png_ptr, png_bytep row, int mask) |
|
2349 { |
|
2350 png_debug(1, "in png_combine_row\n"); |
|
2351 if (mask == 0xff) |
|
2352 { |
|
2353 png_memcpy(row, png_ptr->row_buf + 1, |
|
2354 PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width)); |
|
2355 } |
|
2356 else |
|
2357 { |
|
2358 switch (png_ptr->row_info.pixel_depth) |
|
2359 { |
|
2360 case 1: |
|
2361 { |
|
2362 png_bytep sp = png_ptr->row_buf + 1; |
|
2363 png_bytep dp = row; |
|
2364 int s_inc, s_start, s_end; |
|
2365 int m = 0x80; |
|
2366 int shift; |
|
2367 png_uint_32 i; |
|
2368 png_uint_32 row_width = png_ptr->width; |
|
2369 |
|
2370 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2371 if (png_ptr->transformations & PNG_PACKSWAP) |
|
2372 { |
|
2373 s_start = 0; |
|
2374 s_end = 7; |
|
2375 s_inc = 1; |
|
2376 } |
|
2377 else |
|
2378 #endif |
|
2379 { |
|
2380 s_start = 7; |
|
2381 s_end = 0; |
|
2382 s_inc = -1; |
|
2383 } |
|
2384 |
|
2385 shift = s_start; |
|
2386 |
|
2387 for (i = 0; i < row_width; i++) |
|
2388 { |
|
2389 if (m & mask) |
|
2390 { |
|
2391 int value; |
|
2392 |
|
2393 value = (*sp >> shift) & 0x01; |
|
2394 *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff); |
|
2395 *dp |= (png_byte)(value << shift); |
|
2396 } |
|
2397 |
|
2398 if (shift == s_end) |
|
2399 { |
|
2400 shift = s_start; |
|
2401 sp++; |
|
2402 dp++; |
|
2403 } |
|
2404 else |
|
2405 shift += s_inc; |
|
2406 |
|
2407 if (m == 1) |
|
2408 m = 0x80; |
|
2409 else |
|
2410 m >>= 1; |
|
2411 } |
|
2412 break; |
|
2413 } |
|
2414 case 2: |
|
2415 { |
|
2416 png_bytep sp = png_ptr->row_buf + 1; |
|
2417 png_bytep dp = row; |
|
2418 int s_start, s_end, s_inc; |
|
2419 int m = 0x80; |
|
2420 int shift; |
|
2421 png_uint_32 i; |
|
2422 png_uint_32 row_width = png_ptr->width; |
|
2423 int value; |
|
2424 |
|
2425 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2426 if (png_ptr->transformations & PNG_PACKSWAP) |
|
2427 { |
|
2428 s_start = 0; |
|
2429 s_end = 6; |
|
2430 s_inc = 2; |
|
2431 } |
|
2432 else |
|
2433 #endif |
|
2434 { |
|
2435 s_start = 6; |
|
2436 s_end = 0; |
|
2437 s_inc = -2; |
|
2438 } |
|
2439 |
|
2440 shift = s_start; |
|
2441 |
|
2442 for (i = 0; i < row_width; i++) |
|
2443 { |
|
2444 if (m & mask) |
|
2445 { |
|
2446 value = (*sp >> shift) & 0x03; |
|
2447 *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff); |
|
2448 *dp |= (png_byte)(value << shift); |
|
2449 } |
|
2450 |
|
2451 if (shift == s_end) |
|
2452 { |
|
2453 shift = s_start; |
|
2454 sp++; |
|
2455 dp++; |
|
2456 } |
|
2457 else |
|
2458 shift += s_inc; |
|
2459 if (m == 1) |
|
2460 m = 0x80; |
|
2461 else |
|
2462 m >>= 1; |
|
2463 } |
|
2464 break; |
|
2465 } |
|
2466 case 4: |
|
2467 { |
|
2468 png_bytep sp = png_ptr->row_buf + 1; |
|
2469 png_bytep dp = row; |
|
2470 int s_start, s_end, s_inc; |
|
2471 int m = 0x80; |
|
2472 int shift; |
|
2473 png_uint_32 i; |
|
2474 png_uint_32 row_width = png_ptr->width; |
|
2475 int value; |
|
2476 |
|
2477 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2478 if (png_ptr->transformations & PNG_PACKSWAP) |
|
2479 { |
|
2480 s_start = 0; |
|
2481 s_end = 4; |
|
2482 s_inc = 4; |
|
2483 } |
|
2484 else |
|
2485 #endif |
|
2486 { |
|
2487 s_start = 4; |
|
2488 s_end = 0; |
|
2489 s_inc = -4; |
|
2490 } |
|
2491 shift = s_start; |
|
2492 |
|
2493 for (i = 0; i < row_width; i++) |
|
2494 { |
|
2495 if (m & mask) |
|
2496 { |
|
2497 value = (*sp >> shift) & 0xf; |
|
2498 *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff); |
|
2499 *dp |= (png_byte)(value << shift); |
|
2500 } |
|
2501 |
|
2502 if (shift == s_end) |
|
2503 { |
|
2504 shift = s_start; |
|
2505 sp++; |
|
2506 dp++; |
|
2507 } |
|
2508 else |
|
2509 shift += s_inc; |
|
2510 if (m == 1) |
|
2511 m = 0x80; |
|
2512 else |
|
2513 m >>= 1; |
|
2514 } |
|
2515 break; |
|
2516 } |
|
2517 default: |
|
2518 { |
|
2519 png_bytep sp = png_ptr->row_buf + 1; |
|
2520 png_bytep dp = row; |
|
2521 png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3); |
|
2522 png_uint_32 i; |
|
2523 png_uint_32 row_width = png_ptr->width; |
|
2524 png_byte m = 0x80; |
|
2525 |
|
2526 |
|
2527 for (i = 0; i < row_width; i++) |
|
2528 { |
|
2529 if (m & mask) |
|
2530 { |
|
2531 png_memcpy(dp, sp, pixel_bytes); |
|
2532 } |
|
2533 |
|
2534 sp += pixel_bytes; |
|
2535 dp += pixel_bytes; |
|
2536 |
|
2537 if (m == 1) |
|
2538 m = 0x80; |
|
2539 else |
|
2540 m >>= 1; |
|
2541 } |
|
2542 break; |
|
2543 } |
|
2544 } |
|
2545 } |
|
2546 } |
|
2547 |
|
2548 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
2549 /* OLD pre-1.0.9 interface: |
|
2550 void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass, |
|
2551 png_uint_32 transformations) |
|
2552 */ |
|
2553 void /* PRIVATE */ |
|
2554 png_do_read_interlace(png_structp png_ptr) |
|
2555 { |
|
2556 png_row_infop row_info = &(png_ptr->row_info); |
|
2557 png_bytep row = png_ptr->row_buf + 1; |
|
2558 int pass = png_ptr->pass; |
|
2559 png_uint_32 transformations = png_ptr->transformations; |
|
2560 #ifdef PNG_USE_LOCAL_ARRAYS |
|
2561 /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
|
2562 /* offset to next interlace block */ |
|
2563 PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
|
2564 #endif |
|
2565 |
|
2566 png_debug(1, "in png_do_read_interlace\n"); |
|
2567 if (row != NULL && row_info != NULL) |
|
2568 { |
|
2569 png_uint_32 final_width; |
|
2570 |
|
2571 final_width = row_info->width * png_pass_inc[pass]; |
|
2572 |
|
2573 switch (row_info->pixel_depth) |
|
2574 { |
|
2575 case 1: |
|
2576 { |
|
2577 png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3); |
|
2578 png_bytep dp = row + (png_size_t)((final_width - 1) >> 3); |
|
2579 int sshift, dshift; |
|
2580 int s_start, s_end, s_inc; |
|
2581 int jstop = png_pass_inc[pass]; |
|
2582 png_byte v; |
|
2583 png_uint_32 i; |
|
2584 int j; |
|
2585 |
|
2586 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2587 if (transformations & PNG_PACKSWAP) |
|
2588 { |
|
2589 sshift = (int)((row_info->width + 7) & 0x07); |
|
2590 dshift = (int)((final_width + 7) & 0x07); |
|
2591 s_start = 7; |
|
2592 s_end = 0; |
|
2593 s_inc = -1; |
|
2594 } |
|
2595 else |
|
2596 #endif |
|
2597 { |
|
2598 sshift = 7 - (int)((row_info->width + 7) & 0x07); |
|
2599 dshift = 7 - (int)((final_width + 7) & 0x07); |
|
2600 s_start = 0; |
|
2601 s_end = 7; |
|
2602 s_inc = 1; |
|
2603 } |
|
2604 |
|
2605 for (i = 0; i < row_info->width; i++) |
|
2606 { |
|
2607 v = (png_byte)((*sp >> sshift) & 0x01); |
|
2608 for (j = 0; j < jstop; j++) |
|
2609 { |
|
2610 *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff); |
|
2611 *dp |= (png_byte)(v << dshift); |
|
2612 if (dshift == s_end) |
|
2613 { |
|
2614 dshift = s_start; |
|
2615 dp--; |
|
2616 } |
|
2617 else |
|
2618 dshift += s_inc; |
|
2619 } |
|
2620 if (sshift == s_end) |
|
2621 { |
|
2622 sshift = s_start; |
|
2623 sp--; |
|
2624 } |
|
2625 else |
|
2626 sshift += s_inc; |
|
2627 } |
|
2628 break; |
|
2629 } |
|
2630 case 2: |
|
2631 { |
|
2632 png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2); |
|
2633 png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2); |
|
2634 int sshift, dshift; |
|
2635 int s_start, s_end, s_inc; |
|
2636 int jstop = png_pass_inc[pass]; |
|
2637 png_uint_32 i; |
|
2638 |
|
2639 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2640 if (transformations & PNG_PACKSWAP) |
|
2641 { |
|
2642 sshift = (int)(((row_info->width + 3) & 0x03) << 1); |
|
2643 dshift = (int)(((final_width + 3) & 0x03) << 1); |
|
2644 s_start = 6; |
|
2645 s_end = 0; |
|
2646 s_inc = -2; |
|
2647 } |
|
2648 else |
|
2649 #endif |
|
2650 { |
|
2651 sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1); |
|
2652 dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1); |
|
2653 s_start = 0; |
|
2654 s_end = 6; |
|
2655 s_inc = 2; |
|
2656 } |
|
2657 |
|
2658 for (i = 0; i < row_info->width; i++) |
|
2659 { |
|
2660 png_byte v; |
|
2661 int j; |
|
2662 |
|
2663 v = (png_byte)((*sp >> sshift) & 0x03); |
|
2664 for (j = 0; j < jstop; j++) |
|
2665 { |
|
2666 *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff); |
|
2667 *dp |= (png_byte)(v << dshift); |
|
2668 if (dshift == s_end) |
|
2669 { |
|
2670 dshift = s_start; |
|
2671 dp--; |
|
2672 } |
|
2673 else |
|
2674 dshift += s_inc; |
|
2675 } |
|
2676 if (sshift == s_end) |
|
2677 { |
|
2678 sshift = s_start; |
|
2679 sp--; |
|
2680 } |
|
2681 else |
|
2682 sshift += s_inc; |
|
2683 } |
|
2684 break; |
|
2685 } |
|
2686 case 4: |
|
2687 { |
|
2688 png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1); |
|
2689 png_bytep dp = row + (png_size_t)((final_width - 1) >> 1); |
|
2690 int sshift, dshift; |
|
2691 int s_start, s_end, s_inc; |
|
2692 png_uint_32 i; |
|
2693 int jstop = png_pass_inc[pass]; |
|
2694 |
|
2695 #if defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2696 if (transformations & PNG_PACKSWAP) |
|
2697 { |
|
2698 sshift = (int)(((row_info->width + 1) & 0x01) << 2); |
|
2699 dshift = (int)(((final_width + 1) & 0x01) << 2); |
|
2700 s_start = 4; |
|
2701 s_end = 0; |
|
2702 s_inc = -4; |
|
2703 } |
|
2704 else |
|
2705 #endif |
|
2706 { |
|
2707 sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2); |
|
2708 dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2); |
|
2709 s_start = 0; |
|
2710 s_end = 4; |
|
2711 s_inc = 4; |
|
2712 } |
|
2713 |
|
2714 for (i = 0; i < row_info->width; i++) |
|
2715 { |
|
2716 png_byte v = (png_byte)((*sp >> sshift) & 0xf); |
|
2717 int j; |
|
2718 |
|
2719 for (j = 0; j < jstop; j++) |
|
2720 { |
|
2721 *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff); |
|
2722 *dp |= (png_byte)(v << dshift); |
|
2723 if (dshift == s_end) |
|
2724 { |
|
2725 dshift = s_start; |
|
2726 dp--; |
|
2727 } |
|
2728 else |
|
2729 dshift += s_inc; |
|
2730 } |
|
2731 if (sshift == s_end) |
|
2732 { |
|
2733 sshift = s_start; |
|
2734 sp--; |
|
2735 } |
|
2736 else |
|
2737 sshift += s_inc; |
|
2738 } |
|
2739 break; |
|
2740 } |
|
2741 default: |
|
2742 { |
|
2743 png_size_t pixel_bytes = (row_info->pixel_depth >> 3); |
|
2744 png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes; |
|
2745 png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes; |
|
2746 |
|
2747 int jstop = png_pass_inc[pass]; |
|
2748 png_uint_32 i; |
|
2749 |
|
2750 for (i = 0; i < row_info->width; i++) |
|
2751 { |
|
2752 png_byte v[8]; |
|
2753 int j; |
|
2754 |
|
2755 png_memcpy(v, sp, pixel_bytes); |
|
2756 for (j = 0; j < jstop; j++) |
|
2757 { |
|
2758 png_memcpy(dp, v, pixel_bytes); |
|
2759 dp -= pixel_bytes; |
|
2760 } |
|
2761 sp -= pixel_bytes; |
|
2762 } |
|
2763 break; |
|
2764 } |
|
2765 } |
|
2766 row_info->width = final_width; |
|
2767 row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width); |
|
2768 } |
|
2769 #if !defined(PNG_READ_PACKSWAP_SUPPORTED) |
|
2770 transformations = transformations; /* silence compiler warning */ |
|
2771 #endif |
|
2772 } |
|
2773 #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
|
2774 |
|
2775 void /* PRIVATE */ |
|
2776 png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row, |
|
2777 png_bytep prev_row, int filter) |
|
2778 { |
|
2779 png_debug(1, "in png_read_filter_row\n"); |
|
2780 png_debug2(2, "row = %lu, filter = %d\n", png_ptr->row_number, filter); |
|
2781 switch (filter) |
|
2782 { |
|
2783 case PNG_FILTER_VALUE_NONE: |
|
2784 break; |
|
2785 case PNG_FILTER_VALUE_SUB: |
|
2786 { |
|
2787 png_uint_32 i; |
|
2788 png_uint_32 istop = row_info->rowbytes; |
|
2789 png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3; |
|
2790 png_bytep rp = row + bpp; |
|
2791 png_bytep lp = row; |
|
2792 |
|
2793 for (i = bpp; i < istop; i++) |
|
2794 { |
|
2795 *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff); |
|
2796 rp++; |
|
2797 } |
|
2798 break; |
|
2799 } |
|
2800 case PNG_FILTER_VALUE_UP: |
|
2801 { |
|
2802 png_uint_32 i; |
|
2803 png_uint_32 istop = row_info->rowbytes; |
|
2804 png_bytep rp = row; |
|
2805 png_bytep pp = prev_row; |
|
2806 |
|
2807 for (i = 0; i < istop; i++) |
|
2808 { |
|
2809 *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff); |
|
2810 rp++; |
|
2811 } |
|
2812 break; |
|
2813 } |
|
2814 case PNG_FILTER_VALUE_AVG: |
|
2815 { |
|
2816 png_uint_32 i; |
|
2817 png_bytep rp = row; |
|
2818 png_bytep pp = prev_row; |
|
2819 png_bytep lp = row; |
|
2820 png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3; |
|
2821 png_uint_32 istop = row_info->rowbytes - bpp; |
|
2822 |
|
2823 for (i = 0; i < bpp; i++) |
|
2824 { |
|
2825 *rp = (png_byte)(((int)(*rp) + |
|
2826 ((int)(*pp++) / 2 )) & 0xff); |
|
2827 rp++; |
|
2828 } |
|
2829 |
|
2830 for (i = 0; i < istop; i++) |
|
2831 { |
|
2832 *rp = (png_byte)(((int)(*rp) + |
|
2833 (int)(*pp++ + *lp++) / 2 ) & 0xff); |
|
2834 rp++; |
|
2835 } |
|
2836 break; |
|
2837 } |
|
2838 case PNG_FILTER_VALUE_PAETH: |
|
2839 { |
|
2840 png_uint_32 i; |
|
2841 png_bytep rp = row; |
|
2842 png_bytep pp = prev_row; |
|
2843 png_bytep lp = row; |
|
2844 png_bytep cp = prev_row; |
|
2845 png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3; |
|
2846 png_uint_32 istop=row_info->rowbytes - bpp; |
|
2847 |
|
2848 for (i = 0; i < bpp; i++) |
|
2849 { |
|
2850 *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff); |
|
2851 rp++; |
|
2852 } |
|
2853 |
|
2854 for (i = 0; i < istop; i++) /* use leftover rp,pp */ |
|
2855 { |
|
2856 int a, b, c, pa, pb, pc, p; |
|
2857 |
|
2858 a = *lp++; |
|
2859 b = *pp++; |
|
2860 c = *cp++; |
|
2861 |
|
2862 p = b - c; |
|
2863 pc = a - c; |
|
2864 |
|
2865 #ifdef PNG_USE_ABS |
|
2866 pa = abs(p); |
|
2867 pb = abs(pc); |
|
2868 pc = abs(p + pc); |
|
2869 #else |
|
2870 pa = p < 0 ? -p : p; |
|
2871 pb = pc < 0 ? -pc : pc; |
|
2872 pc = (p + pc) < 0 ? -(p + pc) : p + pc; |
|
2873 #endif |
|
2874 |
|
2875 /* |
|
2876 if (pa <= pb && pa <= pc) |
|
2877 p = a; |
|
2878 else if (pb <= pc) |
|
2879 p = b; |
|
2880 else |
|
2881 p = c; |
|
2882 */ |
|
2883 |
|
2884 p = (pa <= pb && pa <= pc) ? a : (pb <= pc) ? b : c; |
|
2885 |
|
2886 *rp = (png_byte)(((int)(*rp) + p) & 0xff); |
|
2887 rp++; |
|
2888 } |
|
2889 break; |
|
2890 } |
|
2891 default: |
|
2892 png_warning(png_ptr, "Ignoring bad adaptive filter type"); |
|
2893 *row = 0; |
|
2894 break; |
|
2895 } |
|
2896 } |
|
2897 |
|
2898 void /* PRIVATE */ |
|
2899 png_read_finish_row(png_structp png_ptr) |
|
2900 { |
|
2901 #ifdef PNG_USE_LOCAL_ARRAYS |
|
2902 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
2903 /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
|
2904 |
|
2905 /* start of interlace block */ |
|
2906 PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
|
2907 |
|
2908 /* offset to next interlace block */ |
|
2909 PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
|
2910 |
|
2911 /* start of interlace block in the y direction */ |
|
2912 PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; |
|
2913 |
|
2914 /* offset to next interlace block in the y direction */ |
|
2915 PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; |
|
2916 #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
|
2917 #endif |
|
2918 |
|
2919 png_debug(1, "in png_read_finish_row\n"); |
|
2920 png_ptr->row_number++; |
|
2921 if (png_ptr->row_number < png_ptr->num_rows) |
|
2922 return; |
|
2923 |
|
2924 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
2925 if (png_ptr->interlaced) |
|
2926 { |
|
2927 png_ptr->row_number = 0; |
|
2928 png_memset_check(png_ptr, png_ptr->prev_row, 0, |
|
2929 png_ptr->rowbytes + 1); |
|
2930 do |
|
2931 { |
|
2932 png_ptr->pass++; |
|
2933 if (png_ptr->pass >= 7) |
|
2934 break; |
|
2935 png_ptr->iwidth = (png_ptr->width + |
|
2936 png_pass_inc[png_ptr->pass] - 1 - |
|
2937 png_pass_start[png_ptr->pass]) / |
|
2938 png_pass_inc[png_ptr->pass]; |
|
2939 |
|
2940 png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, |
|
2941 png_ptr->iwidth) + 1; |
|
2942 |
|
2943 if (!(png_ptr->transformations & PNG_INTERLACE)) |
|
2944 { |
|
2945 png_ptr->num_rows = (png_ptr->height + |
|
2946 png_pass_yinc[png_ptr->pass] - 1 - |
|
2947 png_pass_ystart[png_ptr->pass]) / |
|
2948 png_pass_yinc[png_ptr->pass]; |
|
2949 if (!(png_ptr->num_rows)) |
|
2950 continue; |
|
2951 } |
|
2952 else /* if (png_ptr->transformations & PNG_INTERLACE) */ |
|
2953 break; |
|
2954 } while (png_ptr->iwidth == 0); |
|
2955 |
|
2956 if (png_ptr->pass < 7) |
|
2957 return; |
|
2958 } |
|
2959 #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
|
2960 |
|
2961 if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED)) |
|
2962 { |
|
2963 #ifdef PNG_USE_LOCAL_ARRAYS |
|
2964 PNG_CONST PNG_IDAT; |
|
2965 #endif |
|
2966 char extra; |
|
2967 int ret; |
|
2968 |
|
2969 png_ptr->zstream.next_out = (Byte *)&extra; |
|
2970 png_ptr->zstream.avail_out = (uInt)1; |
|
2971 for (;;) |
|
2972 { |
|
2973 if (!(png_ptr->zstream.avail_in)) |
|
2974 { |
|
2975 while (!png_ptr->idat_size) |
|
2976 { |
|
2977 png_byte chunk_length[4]; |
|
2978 |
|
2979 png_crc_finish(png_ptr, 0); |
|
2980 |
|
2981 png_read_data(png_ptr, chunk_length, 4); |
|
2982 png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length); |
|
2983 png_reset_crc(png_ptr); |
|
2984 png_crc_read(png_ptr, png_ptr->chunk_name, 4); |
|
2985 if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) |
|
2986 png_error(png_ptr, "Not enough image data"); |
|
2987 |
|
2988 } |
|
2989 png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size; |
|
2990 png_ptr->zstream.next_in = png_ptr->zbuf; |
|
2991 if (png_ptr->zbuf_size > png_ptr->idat_size) |
|
2992 png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size; |
|
2993 png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in); |
|
2994 png_ptr->idat_size -= png_ptr->zstream.avail_in; |
|
2995 } |
|
2996 ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH); |
|
2997 if (ret == Z_STREAM_END) |
|
2998 { |
|
2999 if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in || |
|
3000 png_ptr->idat_size) |
|
3001 png_warning(png_ptr, "Extra compressed data"); |
|
3002 png_ptr->mode |= PNG_AFTER_IDAT; |
|
3003 png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; |
|
3004 break; |
|
3005 } |
|
3006 if (ret != Z_OK) |
|
3007 png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg : |
|
3008 "Decompression Error"); |
|
3009 |
|
3010 if (!(png_ptr->zstream.avail_out)) |
|
3011 { |
|
3012 png_warning(png_ptr, "Extra compressed data."); |
|
3013 png_ptr->mode |= PNG_AFTER_IDAT; |
|
3014 png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED; |
|
3015 break; |
|
3016 } |
|
3017 |
|
3018 } |
|
3019 png_ptr->zstream.avail_out = 0; |
|
3020 } |
|
3021 |
|
3022 if (png_ptr->idat_size || png_ptr->zstream.avail_in) |
|
3023 png_warning(png_ptr, "Extra compression data"); |
|
3024 |
|
3025 inflateReset(&png_ptr->zstream); |
|
3026 |
|
3027 png_ptr->mode |= PNG_AFTER_IDAT; |
|
3028 } |
|
3029 |
|
3030 void /* PRIVATE */ |
|
3031 png_read_start_row(png_structp png_ptr) |
|
3032 { |
|
3033 #ifdef PNG_USE_LOCAL_ARRAYS |
|
3034 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
3035 /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */ |
|
3036 |
|
3037 /* start of interlace block */ |
|
3038 PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0}; |
|
3039 |
|
3040 /* offset to next interlace block */ |
|
3041 PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1}; |
|
3042 |
|
3043 /* start of interlace block in the y direction */ |
|
3044 PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1}; |
|
3045 |
|
3046 /* offset to next interlace block in the y direction */ |
|
3047 PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2}; |
|
3048 #endif |
|
3049 #endif |
|
3050 |
|
3051 int max_pixel_depth; |
|
3052 png_size_t row_bytes; |
|
3053 |
|
3054 png_debug(1, "in png_read_start_row\n"); |
|
3055 png_ptr->zstream.avail_in = 0; |
|
3056 png_init_read_transformations(png_ptr); |
|
3057 #ifdef PNG_READ_INTERLACING_SUPPORTED |
|
3058 if (png_ptr->interlaced) |
|
3059 { |
|
3060 if (!(png_ptr->transformations & PNG_INTERLACE)) |
|
3061 png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 - |
|
3062 png_pass_ystart[0]) / png_pass_yinc[0]; |
|
3063 else |
|
3064 png_ptr->num_rows = png_ptr->height; |
|
3065 |
|
3066 png_ptr->iwidth = (png_ptr->width + |
|
3067 png_pass_inc[png_ptr->pass] - 1 - |
|
3068 png_pass_start[png_ptr->pass]) / |
|
3069 png_pass_inc[png_ptr->pass]; |
|
3070 |
|
3071 png_ptr->irowbytes = |
|
3072 PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1; |
|
3073 } |
|
3074 else |
|
3075 #endif /* PNG_READ_INTERLACING_SUPPORTED */ |
|
3076 { |
|
3077 png_ptr->num_rows = png_ptr->height; |
|
3078 png_ptr->iwidth = png_ptr->width; |
|
3079 png_ptr->irowbytes = png_ptr->rowbytes + 1; |
|
3080 } |
|
3081 max_pixel_depth = png_ptr->pixel_depth; |
|
3082 |
|
3083 #if defined(PNG_READ_PACK_SUPPORTED) |
|
3084 if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8) |
|
3085 max_pixel_depth = 8; |
|
3086 #endif |
|
3087 |
|
3088 #if defined(PNG_READ_EXPAND_SUPPORTED) |
|
3089 if (png_ptr->transformations & PNG_EXPAND) |
|
3090 { |
|
3091 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
3092 { |
|
3093 if (png_ptr->num_trans) |
|
3094 max_pixel_depth = 32; |
|
3095 else |
|
3096 max_pixel_depth = 24; |
|
3097 } |
|
3098 else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) |
|
3099 { |
|
3100 if (max_pixel_depth < 8) |
|
3101 max_pixel_depth = 8; |
|
3102 if (png_ptr->num_trans) |
|
3103 max_pixel_depth *= 2; |
|
3104 } |
|
3105 else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) |
|
3106 { |
|
3107 if (png_ptr->num_trans) |
|
3108 { |
|
3109 max_pixel_depth *= 4; |
|
3110 max_pixel_depth /= 3; |
|
3111 } |
|
3112 } |
|
3113 } |
|
3114 #endif |
|
3115 |
|
3116 #if defined(PNG_READ_FILLER_SUPPORTED) |
|
3117 if (png_ptr->transformations & (PNG_FILLER)) |
|
3118 { |
|
3119 if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) |
|
3120 max_pixel_depth = 32; |
|
3121 else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY) |
|
3122 { |
|
3123 if (max_pixel_depth <= 8) |
|
3124 max_pixel_depth = 16; |
|
3125 else |
|
3126 max_pixel_depth = 32; |
|
3127 } |
|
3128 else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB) |
|
3129 { |
|
3130 if (max_pixel_depth <= 32) |
|
3131 max_pixel_depth = 32; |
|
3132 else |
|
3133 max_pixel_depth = 64; |
|
3134 } |
|
3135 } |
|
3136 #endif |
|
3137 |
|
3138 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) |
|
3139 if (png_ptr->transformations & PNG_GRAY_TO_RGB) |
|
3140 { |
|
3141 if ( |
|
3142 #if defined(PNG_READ_EXPAND_SUPPORTED) |
|
3143 (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) || |
|
3144 #endif |
|
3145 #if defined(PNG_READ_FILLER_SUPPORTED) |
|
3146 (png_ptr->transformations & (PNG_FILLER)) || |
|
3147 #endif |
|
3148 png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA) |
|
3149 { |
|
3150 if (max_pixel_depth <= 16) |
|
3151 max_pixel_depth = 32; |
|
3152 else |
|
3153 max_pixel_depth = 64; |
|
3154 } |
|
3155 else |
|
3156 { |
|
3157 if (max_pixel_depth <= 8) |
|
3158 { |
|
3159 if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
|
3160 max_pixel_depth = 32; |
|
3161 else |
|
3162 max_pixel_depth = 24; |
|
3163 } |
|
3164 else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA) |
|
3165 max_pixel_depth = 64; |
|
3166 else |
|
3167 max_pixel_depth = 48; |
|
3168 } |
|
3169 } |
|
3170 #endif |
|
3171 |
|
3172 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \ |
|
3173 defined(PNG_USER_TRANSFORM_PTR_SUPPORTED) |
|
3174 if (png_ptr->transformations & PNG_USER_TRANSFORM) |
|
3175 { |
|
3176 int user_pixel_depth = png_ptr->user_transform_depth* |
|
3177 png_ptr->user_transform_channels; |
|
3178 if (user_pixel_depth > max_pixel_depth) |
|
3179 max_pixel_depth=user_pixel_depth; |
|
3180 } |
|
3181 #endif |
|
3182 |
|
3183 /* align the width on the next larger 8 pixels. Mainly used |
|
3184 for interlacing */ |
|
3185 row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7)); |
|
3186 /* calculate the maximum bytes needed, adding a byte and a pixel |
|
3187 for safety's sake */ |
|
3188 row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) + |
|
3189 1 + ((max_pixel_depth + 7) >> 3); |
|
3190 #ifdef PNG_MAX_MALLOC_64K |
|
3191 if (row_bytes > (png_uint_32)65536L) |
|
3192 png_error(png_ptr, "This image requires a row greater than 64KB"); |
|
3193 #endif |
|
3194 |
|
3195 if (row_bytes + 64 > png_ptr->old_big_row_buf_size) |
|
3196 { |
|
3197 png_free(png_ptr, png_ptr->big_row_buf); |
|
3198 png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes+64); |
|
3199 png_ptr->row_buf = png_ptr->big_row_buf+32; |
|
3200 png_ptr->old_big_row_buf_size = row_bytes+64; |
|
3201 } |
|
3202 |
|
3203 #ifdef PNG_MAX_MALLOC_64K |
|
3204 if ((png_uint_32)png_ptr->rowbytes + 1 > (png_uint_32)65536L) |
|
3205 png_error(png_ptr, "This image requires a row greater than 64KB"); |
|
3206 #endif |
|
3207 if ((png_uint_32)png_ptr->rowbytes > (png_uint_32)(PNG_SIZE_MAX - 1)) |
|
3208 png_error(png_ptr, "Row has too many bytes to allocate in memory."); |
|
3209 |
|
3210 if (png_ptr->rowbytes+1 > png_ptr->old_prev_row_size) |
|
3211 { |
|
3212 png_free(png_ptr, png_ptr->prev_row); |
|
3213 png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)( |
|
3214 png_ptr->rowbytes + 1)); |
|
3215 png_ptr->old_prev_row_size = png_ptr->rowbytes+1; |
|
3216 } |
|
3217 |
|
3218 png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1); |
|
3219 |
|
3220 png_debug1(3, "width = %lu,\n", png_ptr->width); |
|
3221 png_debug1(3, "height = %lu,\n", png_ptr->height); |
|
3222 png_debug1(3, "iwidth = %lu,\n", png_ptr->iwidth); |
|
3223 png_debug1(3, "num_rows = %lu\n", png_ptr->num_rows); |
|
3224 png_debug1(3, "rowbytes = %lu,\n", png_ptr->rowbytes); |
|
3225 png_debug1(3, "irowbytes = %lu,\n", png_ptr->irowbytes); |
|
3226 |
|
3227 png_ptr->flags |= PNG_FLAG_ROW_INIT; |
|
3228 } |
|
3229 #endif /* PNG_READ_SUPPORTED */ |