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1 /* gun.c -- simple gunzip to give an example of the use of inflateBack() |
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2 * Copyright (C) 2003, 2005 Mark Adler |
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3 * For conditions of distribution and use, see copyright notice in zlib.h |
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4 Version 1.3 12 June 2005 Mark Adler */ |
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5 |
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6 /* Version history: |
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7 1.0 16 Feb 2003 First version for testing of inflateBack() |
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8 1.1 21 Feb 2005 Decompress concatenated gzip streams |
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9 Remove use of "this" variable (C++ keyword) |
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10 Fix return value for in() |
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11 Improve allocation failure checking |
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12 Add typecasting for void * structures |
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13 Add -h option for command version and usage |
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14 Add a bunch of comments |
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15 1.2 20 Mar 2005 Add Unix compress (LZW) decompression |
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16 Copy file attributes from input file to output file |
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17 1.3 12 Jun 2005 Add casts for error messages [Oberhumer] |
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18 */ |
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19 |
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20 /* |
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21 gun [ -t ] [ name ... ] |
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22 |
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23 decompresses the data in the named gzip files. If no arguments are given, |
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24 gun will decompress from stdin to stdout. The names must end in .gz, -gz, |
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25 .z, -z, _z, or .Z. The uncompressed data will be written to a file name |
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26 with the suffix stripped. On success, the original file is deleted. On |
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27 failure, the output file is deleted. For most failures, the command will |
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28 continue to process the remaining names on the command line. A memory |
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29 allocation failure will abort the command. If -t is specified, then the |
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30 listed files or stdin will be tested as gzip files for integrity (without |
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31 checking for a proper suffix), no output will be written, and no files |
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32 will be deleted. |
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33 |
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34 Like gzip, gun allows concatenated gzip streams and will decompress them, |
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35 writing all of the uncompressed data to the output. Unlike gzip, gun allows |
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36 an empty file on input, and will produce no error writing an empty output |
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37 file. |
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38 |
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39 gun will also decompress files made by Unix compress, which uses LZW |
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40 compression. These files are automatically detected by virtue of their |
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41 magic header bytes. Since the end of Unix compress stream is marked by the |
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42 end-of-file, they cannot be concantenated. If a Unix compress stream is |
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43 encountered in an input file, it is the last stream in that file. |
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44 |
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45 Like gunzip and uncompress, the file attributes of the orignal compressed |
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46 file are maintained in the final uncompressed file, to the extent that the |
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47 user permissions allow it. |
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48 |
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49 On my Mac OS X PowerPC G4, gun is almost twice as fast as gunzip (version |
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50 1.2.4) is on the same file, when gun is linked with zlib 1.2.2. Also the |
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51 LZW decompression provided by gun is about twice as fast as the standard |
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52 Unix uncompress command. |
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53 */ |
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54 |
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55 /* external functions and related types and constants */ |
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56 #include <stdio.h> /* fprintf() */ |
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57 #include <stdlib.h> /* malloc(), free() */ |
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58 #include <string.h> /* strerror(), strcmp(), strlen(), memcpy() */ |
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59 #include <errno.h> /* errno */ |
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60 #include <fcntl.h> /* open() */ |
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61 #include <unistd.h> /* read(), write(), close(), chown(), unlink() */ |
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62 #include <sys/types.h> |
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63 #include <sys/stat.h> /* stat(), chmod() */ |
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64 #include <utime.h> /* utime() */ |
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65 #include "zlib.h" /* inflateBackInit(), inflateBack(), */ |
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66 /* inflateBackEnd(), crc32() */ |
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67 |
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68 /* function declaration */ |
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69 #define local static |
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70 |
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71 /* buffer constants */ |
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72 #define SIZE 32768U /* input and output buffer sizes */ |
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73 #define PIECE 16384 /* limits i/o chunks for 16-bit int case */ |
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74 |
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75 /* structure for infback() to pass to input function in() -- it maintains the |
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76 input file and a buffer of size SIZE */ |
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77 struct ind { |
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78 int infile; |
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79 unsigned char *inbuf; |
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80 }; |
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81 |
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82 /* Load input buffer, assumed to be empty, and return bytes loaded and a |
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83 pointer to them. read() is called until the buffer is full, or until it |
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84 returns end-of-file or error. Return 0 on error. */ |
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85 local unsigned in(void *in_desc, unsigned char **buf) |
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86 { |
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87 int ret; |
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88 unsigned len; |
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89 unsigned char *next; |
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90 struct ind *me = (struct ind *)in_desc; |
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91 |
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92 next = me->inbuf; |
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93 *buf = next; |
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94 len = 0; |
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95 do { |
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96 ret = PIECE; |
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97 if ((unsigned)ret > SIZE - len) |
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98 ret = (int)(SIZE - len); |
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99 ret = (int)read(me->infile, next, ret); |
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100 if (ret == -1) { |
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101 len = 0; |
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102 break; |
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103 } |
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104 next += ret; |
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105 len += ret; |
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106 } while (ret != 0 && len < SIZE); |
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107 return len; |
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108 } |
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109 |
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110 /* structure for infback() to pass to output function out() -- it maintains the |
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111 output file, a running CRC-32 check on the output and the total number of |
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112 bytes output, both for checking against the gzip trailer. (The length in |
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113 the gzip trailer is stored modulo 2^32, so it's ok if a long is 32 bits and |
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114 the output is greater than 4 GB.) */ |
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115 struct outd { |
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116 int outfile; |
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117 int check; /* true if checking crc and total */ |
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118 unsigned long crc; |
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119 unsigned long total; |
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120 }; |
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121 |
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122 /* Write output buffer and update the CRC-32 and total bytes written. write() |
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123 is called until all of the output is written or an error is encountered. |
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124 On success out() returns 0. For a write failure, out() returns 1. If the |
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125 output file descriptor is -1, then nothing is written. |
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126 */ |
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127 local int out(void *out_desc, unsigned char *buf, unsigned len) |
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128 { |
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129 int ret; |
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130 struct outd *me = (struct outd *)out_desc; |
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131 |
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132 if (me->check) { |
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133 me->crc = crc32(me->crc, buf, len); |
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134 me->total += len; |
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135 } |
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136 if (me->outfile != -1) |
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137 do { |
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138 ret = PIECE; |
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139 if ((unsigned)ret > len) |
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140 ret = (int)len; |
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141 ret = (int)write(me->outfile, buf, ret); |
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142 if (ret == -1) |
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143 return 1; |
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144 buf += ret; |
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145 len -= ret; |
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146 } while (len != 0); |
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147 return 0; |
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148 } |
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149 |
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150 /* next input byte macro for use inside lunpipe() and gunpipe() */ |
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151 #define NEXT() (have ? 0 : (have = in(indp, &next)), \ |
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152 last = have ? (have--, (int)(*next++)) : -1) |
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153 |
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154 /* memory for gunpipe() and lunpipe() -- |
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155 the first 256 entries of prefix[] and suffix[] are never used, could |
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156 have offset the index, but it's faster to waste the memory */ |
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157 unsigned char inbuf[SIZE]; /* input buffer */ |
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158 unsigned char outbuf[SIZE]; /* output buffer */ |
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159 unsigned short prefix[65536]; /* index to LZW prefix string */ |
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160 unsigned char suffix[65536]; /* one-character LZW suffix */ |
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161 unsigned char match[65280 + 2]; /* buffer for reversed match or gzip |
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162 32K sliding window */ |
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163 |
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164 /* throw out what's left in the current bits byte buffer (this is a vestigial |
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165 aspect of the compressed data format derived from an implementation that |
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166 made use of a special VAX machine instruction!) */ |
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167 #define FLUSHCODE() \ |
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168 do { \ |
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169 left = 0; \ |
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170 rem = 0; \ |
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171 if (chunk > have) { \ |
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172 chunk -= have; \ |
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173 have = 0; \ |
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174 if (NEXT() == -1) \ |
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175 break; \ |
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176 chunk--; \ |
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177 if (chunk > have) { \ |
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178 chunk = have = 0; \ |
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179 break; \ |
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180 } \ |
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181 } \ |
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182 have -= chunk; \ |
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183 next += chunk; \ |
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184 chunk = 0; \ |
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185 } while (0) |
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186 |
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187 /* Decompress a compress (LZW) file from indp to outfile. The compress magic |
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188 header (two bytes) has already been read and verified. There are have bytes |
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189 of buffered input at next. strm is used for passing error information back |
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190 to gunpipe(). |
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191 |
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192 lunpipe() will return Z_OK on success, Z_BUF_ERROR for an unexpected end of |
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193 file, read error, or write error (a write error indicated by strm->next_in |
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194 not equal to Z_NULL), or Z_DATA_ERROR for invalid input. |
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195 */ |
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196 local int lunpipe(unsigned have, unsigned char *next, struct ind *indp, |
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197 int outfile, z_stream *strm) |
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198 { |
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199 int last; /* last byte read by NEXT(), or -1 if EOF */ |
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200 int chunk; /* bytes left in current chunk */ |
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201 int left; /* bits left in rem */ |
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202 unsigned rem; /* unused bits from input */ |
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203 int bits; /* current bits per code */ |
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204 unsigned code; /* code, table traversal index */ |
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205 unsigned mask; /* mask for current bits codes */ |
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206 int max; /* maximum bits per code for this stream */ |
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207 int flags; /* compress flags, then block compress flag */ |
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208 unsigned end; /* last valid entry in prefix/suffix tables */ |
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209 unsigned temp; /* current code */ |
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210 unsigned prev; /* previous code */ |
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211 unsigned final; /* last character written for previous code */ |
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212 unsigned stack; /* next position for reversed string */ |
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213 unsigned outcnt; /* bytes in output buffer */ |
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214 struct outd outd; /* output structure */ |
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215 |
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216 /* set up output */ |
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217 outd.outfile = outfile; |
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218 outd.check = 0; |
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219 |
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220 /* process remainder of compress header -- a flags byte */ |
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221 flags = NEXT(); |
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222 if (last == -1) |
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223 return Z_BUF_ERROR; |
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224 if (flags & 0x60) { |
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225 strm->msg = (char *)"unknown lzw flags set"; |
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226 return Z_DATA_ERROR; |
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227 } |
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228 max = flags & 0x1f; |
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229 if (max < 9 || max > 16) { |
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230 strm->msg = (char *)"lzw bits out of range"; |
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231 return Z_DATA_ERROR; |
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232 } |
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233 if (max == 9) /* 9 doesn't really mean 9 */ |
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234 max = 10; |
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235 flags &= 0x80; /* true if block compress */ |
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236 |
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237 /* clear table */ |
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238 bits = 9; |
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239 mask = 0x1ff; |
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240 end = flags ? 256 : 255; |
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241 |
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242 /* set up: get first 9-bit code, which is the first decompressed byte, but |
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243 don't create a table entry until the next code */ |
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244 if (NEXT() == -1) /* no compressed data is ok */ |
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245 return Z_OK; |
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246 final = prev = (unsigned)last; /* low 8 bits of code */ |
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247 if (NEXT() == -1) /* missing a bit */ |
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248 return Z_BUF_ERROR; |
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249 if (last & 1) { /* code must be < 256 */ |
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250 strm->msg = (char *)"invalid lzw code"; |
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251 return Z_DATA_ERROR; |
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252 } |
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253 rem = (unsigned)last >> 1; /* remaining 7 bits */ |
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254 left = 7; |
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255 chunk = bits - 2; /* 7 bytes left in this chunk */ |
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256 outbuf[0] = (unsigned char)final; /* write first decompressed byte */ |
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257 outcnt = 1; |
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258 |
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259 /* decode codes */ |
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260 stack = 0; |
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261 for (;;) { |
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262 /* if the table will be full after this, increment the code size */ |
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263 if (end >= mask && bits < max) { |
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264 FLUSHCODE(); |
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265 bits++; |
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266 mask <<= 1; |
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267 mask++; |
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268 } |
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269 |
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270 /* get a code of length bits */ |
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271 if (chunk == 0) /* decrement chunk modulo bits */ |
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272 chunk = bits; |
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273 code = rem; /* low bits of code */ |
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274 if (NEXT() == -1) { /* EOF is end of compressed data */ |
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275 /* write remaining buffered output */ |
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276 if (outcnt && out(&outd, outbuf, outcnt)) { |
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277 strm->next_in = outbuf; /* signal write error */ |
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278 return Z_BUF_ERROR; |
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279 } |
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280 return Z_OK; |
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281 } |
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282 code += (unsigned)last << left; /* middle (or high) bits of code */ |
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283 left += 8; |
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284 chunk--; |
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285 if (bits > left) { /* need more bits */ |
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286 if (NEXT() == -1) /* can't end in middle of code */ |
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287 return Z_BUF_ERROR; |
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288 code += (unsigned)last << left; /* high bits of code */ |
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289 left += 8; |
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290 chunk--; |
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291 } |
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292 code &= mask; /* mask to current code length */ |
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293 left -= bits; /* number of unused bits */ |
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294 rem = (unsigned)last >> (8 - left); /* unused bits from last byte */ |
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295 |
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296 /* process clear code (256) */ |
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297 if (code == 256 && flags) { |
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298 FLUSHCODE(); |
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299 bits = 9; /* initialize bits and mask */ |
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300 mask = 0x1ff; |
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301 end = 255; /* empty table */ |
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302 continue; /* get next code */ |
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303 } |
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304 |
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305 /* special code to reuse last match */ |
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306 temp = code; /* save the current code */ |
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307 if (code > end) { |
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308 /* Be picky on the allowed code here, and make sure that the code |
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309 we drop through (prev) will be a valid index so that random |
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310 input does not cause an exception. The code != end + 1 check is |
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311 empirically derived, and not checked in the original uncompress |
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312 code. If this ever causes a problem, that check could be safely |
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313 removed. Leaving this check in greatly improves gun's ability |
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314 to detect random or corrupted input after a compress header. |
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315 In any case, the prev > end check must be retained. */ |
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316 if (code != end + 1 || prev > end) { |
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317 strm->msg = (char *)"invalid lzw code"; |
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318 return Z_DATA_ERROR; |
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319 } |
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320 match[stack++] = (unsigned char)final; |
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321 code = prev; |
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322 } |
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323 |
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324 /* walk through linked list to generate output in reverse order */ |
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325 while (code >= 256) { |
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326 match[stack++] = suffix[code]; |
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327 code = prefix[code]; |
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328 } |
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329 match[stack++] = (unsigned char)code; |
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330 final = code; |
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331 |
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332 /* link new table entry */ |
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333 if (end < mask) { |
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334 end++; |
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335 prefix[end] = (unsigned short)prev; |
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336 suffix[end] = (unsigned char)final; |
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337 } |
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338 |
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339 /* set previous code for next iteration */ |
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340 prev = temp; |
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341 |
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342 /* write output in forward order */ |
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343 while (stack > SIZE - outcnt) { |
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344 while (outcnt < SIZE) |
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345 outbuf[outcnt++] = match[--stack]; |
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346 if (out(&outd, outbuf, outcnt)) { |
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347 strm->next_in = outbuf; /* signal write error */ |
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348 return Z_BUF_ERROR; |
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349 } |
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350 outcnt = 0; |
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351 } |
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352 do { |
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353 outbuf[outcnt++] = match[--stack]; |
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354 } while (stack); |
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355 |
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356 /* loop for next code with final and prev as the last match, rem and |
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357 left provide the first 0..7 bits of the next code, end is the last |
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358 valid table entry */ |
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359 } |
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360 } |
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361 |
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362 /* Decompress a gzip file from infile to outfile. strm is assumed to have been |
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363 successfully initialized with inflateBackInit(). The input file may consist |
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364 of a series of gzip streams, in which case all of them will be decompressed |
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365 to the output file. If outfile is -1, then the gzip stream(s) integrity is |
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366 checked and nothing is written. |
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367 |
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368 The return value is a zlib error code: Z_MEM_ERROR if out of memory, |
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369 Z_DATA_ERROR if the header or the compressed data is invalid, or if the |
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370 trailer CRC-32 check or length doesn't match, Z_BUF_ERROR if the input ends |
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371 prematurely or a write error occurs, or Z_ERRNO if junk (not a another gzip |
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372 stream) follows a valid gzip stream. |
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373 */ |
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374 local int gunpipe(z_stream *strm, int infile, int outfile) |
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375 { |
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376 int ret, first, last; |
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377 unsigned have, flags, len; |
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378 unsigned char *next; |
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379 struct ind ind, *indp; |
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380 struct outd outd; |
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381 |
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382 /* setup input buffer */ |
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383 ind.infile = infile; |
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384 ind.inbuf = inbuf; |
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385 indp = &ind; |
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386 |
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387 /* decompress concatenated gzip streams */ |
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388 have = 0; /* no input data read in yet */ |
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389 first = 1; /* looking for first gzip header */ |
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390 strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ |
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391 for (;;) { |
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392 /* look for the two magic header bytes for a gzip stream */ |
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393 if (NEXT() == -1) { |
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394 ret = Z_OK; |
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395 break; /* empty gzip stream is ok */ |
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396 } |
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397 if (last != 31 || (NEXT() != 139 && last != 157)) { |
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398 strm->msg = (char *)"incorrect header check"; |
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399 ret = first ? Z_DATA_ERROR : Z_ERRNO; |
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400 break; /* not a gzip or compress header */ |
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401 } |
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402 first = 0; /* next non-header is junk */ |
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403 |
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404 /* process a compress (LZW) file -- can't be concatenated after this */ |
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405 if (last == 157) { |
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406 ret = lunpipe(have, next, indp, outfile, strm); |
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407 break; |
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408 } |
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409 |
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410 /* process remainder of gzip header */ |
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411 ret = Z_BUF_ERROR; |
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412 if (NEXT() != 8) { /* only deflate method allowed */ |
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413 if (last == -1) break; |
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414 strm->msg = (char *)"unknown compression method"; |
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415 ret = Z_DATA_ERROR; |
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416 break; |
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417 } |
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418 flags = NEXT(); /* header flags */ |
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419 NEXT(); /* discard mod time, xflgs, os */ |
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420 NEXT(); |
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421 NEXT(); |
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422 NEXT(); |
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423 NEXT(); |
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424 NEXT(); |
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425 if (last == -1) break; |
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426 if (flags & 0xe0) { |
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427 strm->msg = (char *)"unknown header flags set"; |
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428 ret = Z_DATA_ERROR; |
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429 break; |
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430 } |
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431 if (flags & 4) { /* extra field */ |
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432 len = NEXT(); |
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433 len += (unsigned)(NEXT()) << 8; |
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434 if (last == -1) break; |
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435 while (len > have) { |
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436 len -= have; |
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437 have = 0; |
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438 if (NEXT() == -1) break; |
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439 len--; |
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440 } |
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441 if (last == -1) break; |
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442 have -= len; |
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443 next += len; |
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444 } |
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445 if (flags & 8) /* file name */ |
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446 while (NEXT() != 0 && last != -1) |
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447 ; |
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448 if (flags & 16) /* comment */ |
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449 while (NEXT() != 0 && last != -1) |
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450 ; |
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451 if (flags & 2) { /* header crc */ |
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452 NEXT(); |
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453 NEXT(); |
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454 } |
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455 if (last == -1) break; |
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456 |
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457 /* set up output */ |
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458 outd.outfile = outfile; |
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459 outd.check = 1; |
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460 outd.crc = crc32(0L, Z_NULL, 0); |
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461 outd.total = 0; |
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462 |
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463 /* decompress data to output */ |
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464 strm->next_in = next; |
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465 strm->avail_in = have; |
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466 ret = inflateBack(strm, in, indp, out, &outd); |
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467 if (ret != Z_STREAM_END) break; |
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468 next = strm->next_in; |
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469 have = strm->avail_in; |
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470 strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ |
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471 |
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472 /* check trailer */ |
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473 ret = Z_BUF_ERROR; |
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474 if (NEXT() != (outd.crc & 0xff) || |
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475 NEXT() != ((outd.crc >> 8) & 0xff) || |
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476 NEXT() != ((outd.crc >> 16) & 0xff) || |
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477 NEXT() != ((outd.crc >> 24) & 0xff)) { |
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478 /* crc error */ |
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479 if (last != -1) { |
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480 strm->msg = (char *)"incorrect data check"; |
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481 ret = Z_DATA_ERROR; |
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482 } |
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483 break; |
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484 } |
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485 if (NEXT() != (outd.total & 0xff) || |
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486 NEXT() != ((outd.total >> 8) & 0xff) || |
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487 NEXT() != ((outd.total >> 16) & 0xff) || |
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488 NEXT() != ((outd.total >> 24) & 0xff)) { |
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489 /* length error */ |
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490 if (last != -1) { |
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491 strm->msg = (char *)"incorrect length check"; |
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492 ret = Z_DATA_ERROR; |
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493 } |
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494 break; |
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495 } |
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496 |
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497 /* go back and look for another gzip stream */ |
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498 } |
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499 |
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500 /* clean up and return */ |
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501 return ret; |
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502 } |
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503 |
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504 /* Copy file attributes, from -> to, as best we can. This is best effort, so |
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505 no errors are reported. The mode bits, including suid, sgid, and the sticky |
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506 bit are copied (if allowed), the owner's user id and group id are copied |
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507 (again if allowed), and the access and modify times are copied. */ |
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508 local void copymeta(char *from, char *to) |
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509 { |
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510 struct stat was; |
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511 struct utimbuf when; |
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512 |
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513 /* get all of from's Unix meta data, return if not a regular file */ |
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514 if (stat(from, &was) != 0 || (was.st_mode & S_IFMT) != S_IFREG) |
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515 return; |
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516 |
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517 /* set to's mode bits, ignore errors */ |
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518 (void)chmod(to, was.st_mode & 07777); |
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519 |
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520 /* copy owner's user and group, ignore errors */ |
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521 (void)chown(to, was.st_uid, was.st_gid); |
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522 |
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523 /* copy access and modify times, ignore errors */ |
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524 when.actime = was.st_atime; |
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525 when.modtime = was.st_mtime; |
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526 (void)utime(to, &when); |
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527 } |
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528 |
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529 /* Decompress the file inname to the file outnname, of if test is true, just |
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530 decompress without writing and check the gzip trailer for integrity. If |
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531 inname is NULL or an empty string, read from stdin. If outname is NULL or |
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532 an empty string, write to stdout. strm is a pre-initialized inflateBack |
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533 structure. When appropriate, copy the file attributes from inname to |
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534 outname. |
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535 |
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536 gunzip() returns 1 if there is an out-of-memory error or an unexpected |
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537 return code from gunpipe(). Otherwise it returns 0. |
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538 */ |
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539 local int gunzip(z_stream *strm, char *inname, char *outname, int test) |
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540 { |
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541 int ret; |
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542 int infile, outfile; |
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543 |
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544 /* open files */ |
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545 if (inname == NULL || *inname == 0) { |
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546 inname = "-"; |
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547 infile = 0; /* stdin */ |
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548 } |
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549 else { |
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550 infile = open(inname, O_RDONLY, 0); |
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551 if (infile == -1) { |
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552 fprintf(stderr, "gun cannot open %s\n", inname); |
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553 return 0; |
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554 } |
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555 } |
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556 if (test) |
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557 outfile = -1; |
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558 else if (outname == NULL || *outname == 0) { |
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559 outname = "-"; |
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560 outfile = 1; /* stdout */ |
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561 } |
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562 else { |
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563 outfile = open(outname, O_CREAT | O_TRUNC | O_WRONLY, 0666); |
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564 if (outfile == -1) { |
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565 close(infile); |
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566 fprintf(stderr, "gun cannot create %s\n", outname); |
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567 return 0; |
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568 } |
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569 } |
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570 errno = 0; |
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571 |
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572 /* decompress */ |
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573 ret = gunpipe(strm, infile, outfile); |
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574 if (outfile > 2) close(outfile); |
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575 if (infile > 2) close(infile); |
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576 |
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577 /* interpret result */ |
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578 switch (ret) { |
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579 case Z_OK: |
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580 case Z_ERRNO: |
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581 if (infile > 2 && outfile > 2) { |
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582 copymeta(inname, outname); /* copy attributes */ |
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583 unlink(inname); |
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584 } |
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585 if (ret == Z_ERRNO) |
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586 fprintf(stderr, "gun warning: trailing garbage ignored in %s\n", |
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587 inname); |
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588 break; |
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589 case Z_DATA_ERROR: |
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590 if (outfile > 2) unlink(outname); |
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591 fprintf(stderr, "gun data error on %s: %s\n", inname, strm->msg); |
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592 break; |
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593 case Z_MEM_ERROR: |
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594 if (outfile > 2) unlink(outname); |
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595 fprintf(stderr, "gun out of memory error--aborting\n"); |
|
596 return 1; |
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597 case Z_BUF_ERROR: |
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598 if (outfile > 2) unlink(outname); |
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599 if (strm->next_in != Z_NULL) { |
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600 fprintf(stderr, "gun write error on %s: %s\n", |
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601 outname, strerror(errno)); |
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602 } |
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603 else if (errno) { |
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604 fprintf(stderr, "gun read error on %s: %s\n", |
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605 inname, strerror(errno)); |
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606 } |
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607 else { |
|
608 fprintf(stderr, "gun unexpected end of file on %s\n", |
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609 inname); |
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610 } |
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611 break; |
|
612 default: |
|
613 if (outfile > 2) unlink(outname); |
|
614 fprintf(stderr, "gun internal error--aborting\n"); |
|
615 return 1; |
|
616 } |
|
617 return 0; |
|
618 } |
|
619 |
|
620 /* Process the gun command line arguments. See the command syntax near the |
|
621 beginning of this source file. */ |
|
622 int main(int argc, char **argv) |
|
623 { |
|
624 int ret, len, test; |
|
625 char *outname; |
|
626 unsigned char *window; |
|
627 z_stream strm; |
|
628 |
|
629 /* initialize inflateBack state for repeated use */ |
|
630 window = match; /* reuse LZW match buffer */ |
|
631 strm.zalloc = Z_NULL; |
|
632 strm.zfree = Z_NULL; |
|
633 strm.opaque = Z_NULL; |
|
634 ret = inflateBackInit(&strm, 15, window); |
|
635 if (ret != Z_OK) { |
|
636 fprintf(stderr, "gun out of memory error--aborting\n"); |
|
637 return 1; |
|
638 } |
|
639 |
|
640 /* decompress each file to the same name with the suffix removed */ |
|
641 argc--; |
|
642 argv++; |
|
643 test = 0; |
|
644 if (argc && strcmp(*argv, "-h") == 0) { |
|
645 fprintf(stderr, "gun 1.3 (12 Jun 2005)\n"); |
|
646 fprintf(stderr, "Copyright (c) 2005 Mark Adler\n"); |
|
647 fprintf(stderr, "usage: gun [-t] [file1.gz [file2.Z ...]]\n"); |
|
648 return 0; |
|
649 } |
|
650 if (argc && strcmp(*argv, "-t") == 0) { |
|
651 test = 1; |
|
652 argc--; |
|
653 argv++; |
|
654 } |
|
655 if (argc) |
|
656 do { |
|
657 if (test) |
|
658 outname = NULL; |
|
659 else { |
|
660 len = (int)strlen(*argv); |
|
661 if (strcmp(*argv + len - 3, ".gz") == 0 || |
|
662 strcmp(*argv + len - 3, "-gz") == 0) |
|
663 len -= 3; |
|
664 else if (strcmp(*argv + len - 2, ".z") == 0 || |
|
665 strcmp(*argv + len - 2, "-z") == 0 || |
|
666 strcmp(*argv + len - 2, "_z") == 0 || |
|
667 strcmp(*argv + len - 2, ".Z") == 0) |
|
668 len -= 2; |
|
669 else { |
|
670 fprintf(stderr, "gun error: no gz type on %s--skipping\n", |
|
671 *argv); |
|
672 continue; |
|
673 } |
|
674 outname = malloc(len + 1); |
|
675 if (outname == NULL) { |
|
676 fprintf(stderr, "gun out of memory error--aborting\n"); |
|
677 ret = 1; |
|
678 break; |
|
679 } |
|
680 memcpy(outname, *argv, len); |
|
681 outname[len] = 0; |
|
682 } |
|
683 ret = gunzip(&strm, *argv, outname, test); |
|
684 if (outname != NULL) free(outname); |
|
685 if (ret) break; |
|
686 } while (argv++, --argc); |
|
687 else |
|
688 ret = gunzip(&strm, NULL, NULL, test); |
|
689 |
|
690 /* clean up */ |
|
691 inflateBackEnd(&strm); |
|
692 return ret; |
|
693 } |