1 | /* gun.c -- simple gunzip to give an example of the use of inflateBack() |
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2 | * Copyright (C) 2003, 2005, 2008, 2010 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 1.6 17 January 2010 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 | 1.4 8 Dec 2006 LZW decompression speed improvements |
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19 | 1.5 9 Feb 2008 Avoid warning in latest version of gcc |
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20 | 1.6 17 Jan 2010 Avoid signed/unsigned comparison warnings |
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21 | */ |
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22 | |
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23 | /* |
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24 | gun [ -t ] [ name ... ] |
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25 | |
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26 | decompresses the data in the named gzip files. If no arguments are given, |
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27 | gun will decompress from stdin to stdout. The names must end in .gz, -gz, |
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28 | .z, -z, _z, or .Z. The uncompressed data will be written to a file name |
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29 | with the suffix stripped. On success, the original file is deleted. On |
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30 | failure, the output file is deleted. For most failures, the command will |
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31 | continue to process the remaining names on the command line. A memory |
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32 | allocation failure will abort the command. If -t is specified, then the |
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33 | listed files or stdin will be tested as gzip files for integrity (without |
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34 | checking for a proper suffix), no output will be written, and no files |
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35 | will be deleted. |
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36 | |
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37 | Like gzip, gun allows concatenated gzip streams and will decompress them, |
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38 | writing all of the uncompressed data to the output. Unlike gzip, gun allows |
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39 | an empty file on input, and will produce no error writing an empty output |
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40 | file. |
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41 | |
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42 | gun will also decompress files made by Unix compress, which uses LZW |
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43 | compression. These files are automatically detected by virtue of their |
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44 | magic header bytes. Since the end of Unix compress stream is marked by the |
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45 | end-of-file, they cannot be concantenated. If a Unix compress stream is |
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46 | encountered in an input file, it is the last stream in that file. |
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47 | |
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48 | Like gunzip and uncompress, the file attributes of the orignal compressed |
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49 | file are maintained in the final uncompressed file, to the extent that the |
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50 | user permissions allow it. |
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51 | |
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52 | On my Mac OS X PowerPC G4, gun is almost twice as fast as gunzip (version |
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53 | 1.2.4) is on the same file, when gun is linked with zlib 1.2.2. Also the |
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54 | LZW decompression provided by gun is about twice as fast as the standard |
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55 | Unix uncompress command. |
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56 | */ |
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57 | |
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58 | /* external functions and related types and constants */ |
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59 | #include <stdio.h> /* fprintf() */ |
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60 | #include <stdlib.h> /* malloc(), free() */ |
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61 | #include <string.h> /* strerror(), strcmp(), strlen(), memcpy() */ |
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62 | #include <errno.h> /* errno */ |
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63 | #include <fcntl.h> /* open() */ |
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64 | #include <unistd.h> /* read(), write(), close(), chown(), unlink() */ |
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65 | #include <sys/types.h> |
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66 | #include <sys/stat.h> /* stat(), chmod() */ |
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67 | #include <utime.h> /* utime() */ |
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68 | #include "zlib.h" /* inflateBackInit(), inflateBack(), */ |
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69 | /* inflateBackEnd(), crc32() */ |
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70 | |
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71 | /* function declaration */ |
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72 | #define local static |
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73 | |
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74 | /* buffer constants */ |
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75 | #define SIZE 32768U /* input and output buffer sizes */ |
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76 | #define PIECE 16384 /* limits i/o chunks for 16-bit int case */ |
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77 | |
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78 | /* structure for infback() to pass to input function in() -- it maintains the |
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79 | input file and a buffer of size SIZE */ |
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80 | struct ind { |
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81 | int infile; |
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82 | unsigned char *inbuf; |
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83 | }; |
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84 | |
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85 | /* Load input buffer, assumed to be empty, and return bytes loaded and a |
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86 | pointer to them. read() is called until the buffer is full, or until it |
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87 | returns end-of-file or error. Return 0 on error. */ |
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88 | local unsigned in(void *in_desc, unsigned char **buf) |
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89 | { |
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90 | int ret; |
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91 | unsigned len; |
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92 | unsigned char *next; |
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93 | struct ind *me = (struct ind *)in_desc; |
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94 | |
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95 | next = me->inbuf; |
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96 | *buf = next; |
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97 | len = 0; |
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98 | do { |
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99 | ret = PIECE; |
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100 | if ((unsigned)ret > SIZE - len) |
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101 | ret = (int)(SIZE - len); |
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102 | ret = (int)read(me->infile, next, ret); |
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103 | if (ret == -1) { |
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104 | len = 0; |
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105 | break; |
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106 | } |
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107 | next += ret; |
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108 | len += ret; |
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109 | } while (ret != 0 && len < SIZE); |
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110 | return len; |
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111 | } |
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112 | |
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113 | /* structure for infback() to pass to output function out() -- it maintains the |
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114 | output file, a running CRC-32 check on the output and the total number of |
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115 | bytes output, both for checking against the gzip trailer. (The length in |
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116 | the gzip trailer is stored modulo 2^32, so it's ok if a long is 32 bits and |
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117 | the output is greater than 4 GB.) */ |
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118 | struct outd { |
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119 | int outfile; |
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120 | int check; /* true if checking crc and total */ |
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121 | unsigned long crc; |
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122 | unsigned long total; |
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123 | }; |
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124 | |
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125 | /* Write output buffer and update the CRC-32 and total bytes written. write() |
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126 | is called until all of the output is written or an error is encountered. |
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127 | On success out() returns 0. For a write failure, out() returns 1. If the |
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128 | output file descriptor is -1, then nothing is written. |
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129 | */ |
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130 | local int out(void *out_desc, unsigned char *buf, unsigned len) |
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131 | { |
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132 | int ret; |
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133 | struct outd *me = (struct outd *)out_desc; |
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134 | |
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135 | if (me->check) { |
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136 | me->crc = crc32(me->crc, buf, len); |
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137 | me->total += len; |
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138 | } |
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139 | if (me->outfile != -1) |
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140 | do { |
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141 | ret = PIECE; |
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142 | if ((unsigned)ret > len) |
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143 | ret = (int)len; |
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144 | ret = (int)write(me->outfile, buf, ret); |
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145 | if (ret == -1) |
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146 | return 1; |
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147 | buf += ret; |
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148 | len -= ret; |
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149 | } while (len != 0); |
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150 | return 0; |
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151 | } |
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152 | |
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153 | /* next input byte macro for use inside lunpipe() and gunpipe() */ |
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154 | #define NEXT() (have ? 0 : (have = in(indp, &next)), \ |
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155 | last = have ? (have--, (int)(*next++)) : -1) |
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156 | |
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157 | /* memory for gunpipe() and lunpipe() -- |
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158 | the first 256 entries of prefix[] and suffix[] are never used, could |
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159 | have offset the index, but it's faster to waste the memory */ |
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160 | unsigned char inbuf[SIZE]; /* input buffer */ |
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161 | unsigned char outbuf[SIZE]; /* output buffer */ |
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162 | unsigned short prefix[65536]; /* index to LZW prefix string */ |
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163 | unsigned char suffix[65536]; /* one-character LZW suffix */ |
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164 | unsigned char match[65280 + 2]; /* buffer for reversed match or gzip |
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165 | 32K sliding window */ |
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166 | |
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167 | /* throw out what's left in the current bits byte buffer (this is a vestigial |
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168 | aspect of the compressed data format derived from an implementation that |
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169 | made use of a special VAX machine instruction!) */ |
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170 | #define FLUSHCODE() \ |
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171 | do { \ |
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172 | left = 0; \ |
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173 | rem = 0; \ |
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174 | if (chunk > have) { \ |
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175 | chunk -= have; \ |
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176 | have = 0; \ |
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177 | if (NEXT() == -1) \ |
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178 | break; \ |
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179 | chunk--; \ |
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180 | if (chunk > have) { \ |
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181 | chunk = have = 0; \ |
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182 | break; \ |
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183 | } \ |
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184 | } \ |
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185 | have -= chunk; \ |
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186 | next += chunk; \ |
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187 | chunk = 0; \ |
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188 | } while (0) |
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189 | |
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190 | /* Decompress a compress (LZW) file from indp to outfile. The compress magic |
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191 | header (two bytes) has already been read and verified. There are have bytes |
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192 | of buffered input at next. strm is used for passing error information back |
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193 | to gunpipe(). |
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194 | |
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195 | lunpipe() will return Z_OK on success, Z_BUF_ERROR for an unexpected end of |
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196 | file, read error, or write error (a write error indicated by strm->next_in |
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197 | not equal to Z_NULL), or Z_DATA_ERROR for invalid input. |
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198 | */ |
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199 | local int lunpipe(unsigned have, unsigned char *next, struct ind *indp, |
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200 | int outfile, z_stream *strm) |
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201 | { |
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202 | int last; /* last byte read by NEXT(), or -1 if EOF */ |
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203 | unsigned chunk; /* bytes left in current chunk */ |
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204 | int left; /* bits left in rem */ |
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205 | unsigned rem; /* unused bits from input */ |
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206 | int bits; /* current bits per code */ |
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207 | unsigned code; /* code, table traversal index */ |
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208 | unsigned mask; /* mask for current bits codes */ |
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209 | int max; /* maximum bits per code for this stream */ |
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210 | unsigned flags; /* compress flags, then block compress flag */ |
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211 | unsigned end; /* last valid entry in prefix/suffix tables */ |
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212 | unsigned temp; /* current code */ |
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213 | unsigned prev; /* previous code */ |
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214 | unsigned final; /* last character written for previous code */ |
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215 | unsigned stack; /* next position for reversed string */ |
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216 | unsigned outcnt; /* bytes in output buffer */ |
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217 | struct outd outd; /* output structure */ |
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218 | unsigned char *p; |
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219 | |
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220 | /* set up output */ |
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221 | outd.outfile = outfile; |
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222 | outd.check = 0; |
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223 | |
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224 | /* process remainder of compress header -- a flags byte */ |
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225 | flags = NEXT(); |
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226 | if (last == -1) |
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227 | return Z_BUF_ERROR; |
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228 | if (flags & 0x60) { |
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229 | strm->msg = (char *)"unknown lzw flags set"; |
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230 | return Z_DATA_ERROR; |
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231 | } |
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232 | max = flags & 0x1f; |
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233 | if (max < 9 || max > 16) { |
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234 | strm->msg = (char *)"lzw bits out of range"; |
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235 | return Z_DATA_ERROR; |
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236 | } |
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237 | if (max == 9) /* 9 doesn't really mean 9 */ |
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238 | max = 10; |
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239 | flags &= 0x80; /* true if block compress */ |
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240 | |
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241 | /* clear table */ |
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242 | bits = 9; |
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243 | mask = 0x1ff; |
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244 | end = flags ? 256 : 255; |
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245 | |
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246 | /* set up: get first 9-bit code, which is the first decompressed byte, but |
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247 | don't create a table entry until the next code */ |
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248 | if (NEXT() == -1) /* no compressed data is ok */ |
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249 | return Z_OK; |
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250 | final = prev = (unsigned)last; /* low 8 bits of code */ |
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251 | if (NEXT() == -1) /* missing a bit */ |
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252 | return Z_BUF_ERROR; |
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253 | if (last & 1) { /* code must be < 256 */ |
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254 | strm->msg = (char *)"invalid lzw code"; |
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255 | return Z_DATA_ERROR; |
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256 | } |
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257 | rem = (unsigned)last >> 1; /* remaining 7 bits */ |
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258 | left = 7; |
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259 | chunk = bits - 2; /* 7 bytes left in this chunk */ |
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260 | outbuf[0] = (unsigned char)final; /* write first decompressed byte */ |
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261 | outcnt = 1; |
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262 | |
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263 | /* decode codes */ |
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264 | stack = 0; |
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265 | for (;;) { |
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266 | /* if the table will be full after this, increment the code size */ |
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267 | if (end >= mask && bits < max) { |
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268 | FLUSHCODE(); |
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269 | bits++; |
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270 | mask <<= 1; |
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271 | mask++; |
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272 | } |
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273 | |
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274 | /* get a code of length bits */ |
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275 | if (chunk == 0) /* decrement chunk modulo bits */ |
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276 | chunk = bits; |
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277 | code = rem; /* low bits of code */ |
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278 | if (NEXT() == -1) { /* EOF is end of compressed data */ |
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279 | /* write remaining buffered output */ |
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280 | if (outcnt && out(&outd, outbuf, outcnt)) { |
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281 | strm->next_in = outbuf; /* signal write error */ |
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282 | return Z_BUF_ERROR; |
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283 | } |
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284 | return Z_OK; |
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285 | } |
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286 | code += (unsigned)last << left; /* middle (or high) bits of code */ |
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287 | left += 8; |
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288 | chunk--; |
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289 | if (bits > left) { /* need more bits */ |
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290 | if (NEXT() == -1) /* can't end in middle of code */ |
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291 | return Z_BUF_ERROR; |
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292 | code += (unsigned)last << left; /* high bits of code */ |
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293 | left += 8; |
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294 | chunk--; |
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295 | } |
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296 | code &= mask; /* mask to current code length */ |
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297 | left -= bits; /* number of unused bits */ |
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298 | rem = (unsigned)last >> (8 - left); /* unused bits from last byte */ |
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299 | |
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300 | /* process clear code (256) */ |
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301 | if (code == 256 && flags) { |
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302 | FLUSHCODE(); |
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303 | bits = 9; /* initialize bits and mask */ |
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304 | mask = 0x1ff; |
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305 | end = 255; /* empty table */ |
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306 | continue; /* get next code */ |
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307 | } |
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308 | |
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309 | /* special code to reuse last match */ |
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310 | temp = code; /* save the current code */ |
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311 | if (code > end) { |
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312 | /* Be picky on the allowed code here, and make sure that the code |
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313 | we drop through (prev) will be a valid index so that random |
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314 | input does not cause an exception. The code != end + 1 check is |
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315 | empirically derived, and not checked in the original uncompress |
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316 | code. If this ever causes a problem, that check could be safely |
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317 | removed. Leaving this check in greatly improves gun's ability |
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318 | to detect random or corrupted input after a compress header. |
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319 | In any case, the prev > end check must be retained. */ |
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320 | if (code != end + 1 || prev > end) { |
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321 | strm->msg = (char *)"invalid lzw code"; |
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322 | return Z_DATA_ERROR; |
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323 | } |
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324 | match[stack++] = (unsigned char)final; |
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325 | code = prev; |
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326 | } |
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327 | |
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328 | /* walk through linked list to generate output in reverse order */ |
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329 | p = match + stack; |
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330 | while (code >= 256) { |
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331 | *p++ = suffix[code]; |
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332 | code = prefix[code]; |
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333 | } |
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334 | stack = p - match; |
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335 | match[stack++] = (unsigned char)code; |
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336 | final = code; |
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337 | |
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338 | /* link new table entry */ |
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339 | if (end < mask) { |
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340 | end++; |
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341 | prefix[end] = (unsigned short)prev; |
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342 | suffix[end] = (unsigned char)final; |
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343 | } |
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344 | |
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345 | /* set previous code for next iteration */ |
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346 | prev = temp; |
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347 | |
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348 | /* write output in forward order */ |
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349 | while (stack > SIZE - outcnt) { |
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350 | while (outcnt < SIZE) |
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351 | outbuf[outcnt++] = match[--stack]; |
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352 | if (out(&outd, outbuf, outcnt)) { |
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353 | strm->next_in = outbuf; /* signal write error */ |
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354 | return Z_BUF_ERROR; |
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355 | } |
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356 | outcnt = 0; |
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357 | } |
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358 | p = match + stack; |
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359 | do { |
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360 | outbuf[outcnt++] = *--p; |
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361 | } while (p > match); |
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362 | stack = 0; |
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363 | |
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364 | /* loop for next code with final and prev as the last match, rem and |
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365 | left provide the first 0..7 bits of the next code, end is the last |
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366 | valid table entry */ |
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367 | } |
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368 | } |
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369 | |
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370 | /* Decompress a gzip file from infile to outfile. strm is assumed to have been |
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371 | successfully initialized with inflateBackInit(). The input file may consist |
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372 | of a series of gzip streams, in which case all of them will be decompressed |
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373 | to the output file. If outfile is -1, then the gzip stream(s) integrity is |
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374 | checked and nothing is written. |
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375 | |
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376 | The return value is a zlib error code: Z_MEM_ERROR if out of memory, |
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377 | Z_DATA_ERROR if the header or the compressed data is invalid, or if the |
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378 | trailer CRC-32 check or length doesn't match, Z_BUF_ERROR if the input ends |
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379 | prematurely or a write error occurs, or Z_ERRNO if junk (not a another gzip |
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380 | stream) follows a valid gzip stream. |
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381 | */ |
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382 | local int gunpipe(z_stream *strm, int infile, int outfile) |
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383 | { |
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384 | int ret, first, last; |
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385 | unsigned have, flags, len; |
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386 | unsigned char *next = NULL; |
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387 | struct ind ind, *indp; |
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388 | struct outd outd; |
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389 | |
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390 | /* setup input buffer */ |
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391 | ind.infile = infile; |
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392 | ind.inbuf = inbuf; |
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393 | indp = &ind; |
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394 | |
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395 | /* decompress concatenated gzip streams */ |
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396 | have = 0; /* no input data read in yet */ |
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397 | first = 1; /* looking for first gzip header */ |
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398 | strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ |
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399 | for (;;) { |
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400 | /* look for the two magic header bytes for a gzip stream */ |
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401 | if (NEXT() == -1) { |
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402 | ret = Z_OK; |
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403 | break; /* empty gzip stream is ok */ |
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404 | } |
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405 | if (last != 31 || (NEXT() != 139 && last != 157)) { |
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406 | strm->msg = (char *)"incorrect header check"; |
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407 | ret = first ? Z_DATA_ERROR : Z_ERRNO; |
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408 | break; /* not a gzip or compress header */ |
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409 | } |
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410 | first = 0; /* next non-header is junk */ |
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411 | |
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412 | /* process a compress (LZW) file -- can't be concatenated after this */ |
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413 | if (last == 157) { |
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414 | ret = lunpipe(have, next, indp, outfile, strm); |
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415 | break; |
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416 | } |
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417 | |
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418 | /* process remainder of gzip header */ |
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419 | ret = Z_BUF_ERROR; |
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420 | if (NEXT() != 8) { /* only deflate method allowed */ |
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421 | if (last == -1) break; |
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422 | strm->msg = (char *)"unknown compression method"; |
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423 | ret = Z_DATA_ERROR; |
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424 | break; |
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425 | } |
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426 | flags = NEXT(); /* header flags */ |
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427 | NEXT(); /* discard mod time, xflgs, os */ |
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428 | NEXT(); |
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429 | NEXT(); |
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430 | NEXT(); |
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431 | NEXT(); |
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432 | NEXT(); |
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433 | if (last == -1) break; |
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434 | if (flags & 0xe0) { |
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435 | strm->msg = (char *)"unknown header flags set"; |
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436 | ret = Z_DATA_ERROR; |
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437 | break; |
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438 | } |
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439 | if (flags & 4) { /* extra field */ |
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440 | len = NEXT(); |
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441 | len += (unsigned)(NEXT()) << 8; |
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442 | if (last == -1) break; |
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443 | while (len > have) { |
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444 | len -= have; |
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445 | have = 0; |
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446 | if (NEXT() == -1) break; |
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447 | len--; |
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448 | } |
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449 | if (last == -1) break; |
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450 | have -= len; |
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451 | next += len; |
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452 | } |
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453 | if (flags & 8) /* file name */ |
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454 | while (NEXT() != 0 && last != -1) |
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455 | ; |
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456 | if (flags & 16) /* comment */ |
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457 | while (NEXT() != 0 && last != -1) |
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458 | ; |
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459 | if (flags & 2) { /* header crc */ |
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460 | NEXT(); |
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461 | NEXT(); |
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462 | } |
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463 | if (last == -1) break; |
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464 | |
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465 | /* set up output */ |
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466 | outd.outfile = outfile; |
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467 | outd.check = 1; |
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468 | outd.crc = crc32(0L, Z_NULL, 0); |
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469 | outd.total = 0; |
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470 | |
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471 | /* decompress data to output */ |
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472 | strm->next_in = next; |
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473 | strm->avail_in = have; |
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474 | ret = inflateBack(strm, in, indp, out, &outd); |
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475 | if (ret != Z_STREAM_END) break; |
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476 | next = strm->next_in; |
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477 | have = strm->avail_in; |
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478 | strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ |
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479 | |
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480 | /* check trailer */ |
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481 | ret = Z_BUF_ERROR; |
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482 | if (NEXT() != (int)(outd.crc & 0xff) || |
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483 | NEXT() != (int)((outd.crc >> 8) & 0xff) || |
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484 | NEXT() != (int)((outd.crc >> 16) & 0xff) || |
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485 | NEXT() != (int)((outd.crc >> 24) & 0xff)) { |
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486 | /* crc error */ |
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487 | if (last != -1) { |
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488 | strm->msg = (char *)"incorrect data check"; |
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489 | ret = Z_DATA_ERROR; |
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490 | } |
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491 | break; |
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492 | } |
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493 | if (NEXT() != (int)(outd.total & 0xff) || |
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494 | NEXT() != (int)((outd.total >> 8) & 0xff) || |
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495 | NEXT() != (int)((outd.total >> 16) & 0xff) || |
---|
496 | NEXT() != (int)((outd.total >> 24) & 0xff)) { |
---|
497 | /* length error */ |
---|
498 | if (last != -1) { |
---|
499 | strm->msg = (char *)"incorrect length check"; |
---|
500 | ret = Z_DATA_ERROR; |
---|
501 | } |
---|
502 | break; |
---|
503 | } |
---|
504 | |
---|
505 | /* go back and look for another gzip stream */ |
---|
506 | } |
---|
507 | |
---|
508 | /* clean up and return */ |
---|
509 | return ret; |
---|
510 | } |
---|
511 | |
---|
512 | /* Copy file attributes, from -> to, as best we can. This is best effort, so |
---|
513 | no errors are reported. The mode bits, including suid, sgid, and the sticky |
---|
514 | bit are copied (if allowed), the owner's user id and group id are copied |
---|
515 | (again if allowed), and the access and modify times are copied. */ |
---|
516 | local void copymeta(char *from, char *to) |
---|
517 | { |
---|
518 | struct stat was; |
---|
519 | struct utimbuf when; |
---|
520 | |
---|
521 | /* get all of from's Unix meta data, return if not a regular file */ |
---|
522 | if (stat(from, &was) != 0 || (was.st_mode & S_IFMT) != S_IFREG) |
---|
523 | return; |
---|
524 | |
---|
525 | /* set to's mode bits, ignore errors */ |
---|
526 | (void)chmod(to, was.st_mode & 07777); |
---|
527 | |
---|
528 | /* copy owner's user and group, ignore errors */ |
---|
529 | (void)chown(to, was.st_uid, was.st_gid); |
---|
530 | |
---|
531 | /* copy access and modify times, ignore errors */ |
---|
532 | when.actime = was.st_atime; |
---|
533 | when.modtime = was.st_mtime; |
---|
534 | (void)utime(to, &when); |
---|
535 | } |
---|
536 | |
---|
537 | /* Decompress the file inname to the file outnname, of if test is true, just |
---|
538 | decompress without writing and check the gzip trailer for integrity. If |
---|
539 | inname is NULL or an empty string, read from stdin. If outname is NULL or |
---|
540 | an empty string, write to stdout. strm is a pre-initialized inflateBack |
---|
541 | structure. When appropriate, copy the file attributes from inname to |
---|
542 | outname. |
---|
543 | |
---|
544 | gunzip() returns 1 if there is an out-of-memory error or an unexpected |
---|
545 | return code from gunpipe(). Otherwise it returns 0. |
---|
546 | */ |
---|
547 | local int gunzip(z_stream *strm, char *inname, char *outname, int test) |
---|
548 | { |
---|
549 | int ret; |
---|
550 | int infile, outfile; |
---|
551 | |
---|
552 | /* open files */ |
---|
553 | if (inname == NULL || *inname == 0) { |
---|
554 | inname = "-"; |
---|
555 | infile = 0; /* stdin */ |
---|
556 | } |
---|
557 | else { |
---|
558 | infile = open(inname, O_RDONLY, 0); |
---|
559 | if (infile == -1) { |
---|
560 | fprintf(stderr, "gun cannot open %s\n", inname); |
---|
561 | return 0; |
---|
562 | } |
---|
563 | } |
---|
564 | if (test) |
---|
565 | outfile = -1; |
---|
566 | else if (outname == NULL || *outname == 0) { |
---|
567 | outname = "-"; |
---|
568 | outfile = 1; /* stdout */ |
---|
569 | } |
---|
570 | else { |
---|
571 | outfile = open(outname, O_CREAT | O_TRUNC | O_WRONLY, 0666); |
---|
572 | if (outfile == -1) { |
---|
573 | close(infile); |
---|
574 | fprintf(stderr, "gun cannot create %s\n", outname); |
---|
575 | return 0; |
---|
576 | } |
---|
577 | } |
---|
578 | errno = 0; |
---|
579 | |
---|
580 | /* decompress */ |
---|
581 | ret = gunpipe(strm, infile, outfile); |
---|
582 | if (outfile > 2) close(outfile); |
---|
583 | if (infile > 2) close(infile); |
---|
584 | |
---|
585 | /* interpret result */ |
---|
586 | switch (ret) { |
---|
587 | case Z_OK: |
---|
588 | case Z_ERRNO: |
---|
589 | if (infile > 2 && outfile > 2) { |
---|
590 | copymeta(inname, outname); /* copy attributes */ |
---|
591 | unlink(inname); |
---|
592 | } |
---|
593 | if (ret == Z_ERRNO) |
---|
594 | fprintf(stderr, "gun warning: trailing garbage ignored in %s\n", |
---|
595 | inname); |
---|
596 | break; |
---|
597 | case Z_DATA_ERROR: |
---|
598 | if (outfile > 2) unlink(outname); |
---|
599 | fprintf(stderr, "gun data error on %s: %s\n", inname, strm->msg); |
---|
600 | break; |
---|
601 | case Z_MEM_ERROR: |
---|
602 | if (outfile > 2) unlink(outname); |
---|
603 | fprintf(stderr, "gun out of memory error--aborting\n"); |
---|
604 | return 1; |
---|
605 | case Z_BUF_ERROR: |
---|
606 | if (outfile > 2) unlink(outname); |
---|
607 | if (strm->next_in != Z_NULL) { |
---|
608 | fprintf(stderr, "gun write error on %s: %s\n", |
---|
609 | outname, strerror(errno)); |
---|
610 | } |
---|
611 | else if (errno) { |
---|
612 | fprintf(stderr, "gun read error on %s: %s\n", |
---|
613 | inname, strerror(errno)); |
---|
614 | } |
---|
615 | else { |
---|
616 | fprintf(stderr, "gun unexpected end of file on %s\n", |
---|
617 | inname); |
---|
618 | } |
---|
619 | break; |
---|
620 | default: |
---|
621 | if (outfile > 2) unlink(outname); |
---|
622 | fprintf(stderr, "gun internal error--aborting\n"); |
---|
623 | return 1; |
---|
624 | } |
---|
625 | return 0; |
---|
626 | } |
---|
627 | |
---|
628 | /* Process the gun command line arguments. See the command syntax near the |
---|
629 | beginning of this source file. */ |
---|
630 | int main(int argc, char **argv) |
---|
631 | { |
---|
632 | int ret, len, test; |
---|
633 | char *outname; |
---|
634 | unsigned char *window; |
---|
635 | z_stream strm; |
---|
636 | |
---|
637 | /* initialize inflateBack state for repeated use */ |
---|
638 | window = match; /* reuse LZW match buffer */ |
---|
639 | strm.zalloc = Z_NULL; |
---|
640 | strm.zfree = Z_NULL; |
---|
641 | strm.opaque = Z_NULL; |
---|
642 | ret = inflateBackInit(&strm, 15, window); |
---|
643 | if (ret != Z_OK) { |
---|
644 | fprintf(stderr, "gun out of memory error--aborting\n"); |
---|
645 | return 1; |
---|
646 | } |
---|
647 | |
---|
648 | /* decompress each file to the same name with the suffix removed */ |
---|
649 | argc--; |
---|
650 | argv++; |
---|
651 | test = 0; |
---|
652 | if (argc && strcmp(*argv, "-h") == 0) { |
---|
653 | fprintf(stderr, "gun 1.6 (17 Jan 2010)\n"); |
---|
654 | fprintf(stderr, "Copyright (C) 2003-2010 Mark Adler\n"); |
---|
655 | fprintf(stderr, "usage: gun [-t] [file1.gz [file2.Z ...]]\n"); |
---|
656 | return 0; |
---|
657 | } |
---|
658 | if (argc && strcmp(*argv, "-t") == 0) { |
---|
659 | test = 1; |
---|
660 | argc--; |
---|
661 | argv++; |
---|
662 | } |
---|
663 | if (argc) |
---|
664 | do { |
---|
665 | if (test) |
---|
666 | outname = NULL; |
---|
667 | else { |
---|
668 | len = (int)strlen(*argv); |
---|
669 | if (strcmp(*argv + len - 3, ".gz") == 0 || |
---|
670 | strcmp(*argv + len - 3, "-gz") == 0) |
---|
671 | len -= 3; |
---|
672 | else if (strcmp(*argv + len - 2, ".z") == 0 || |
---|
673 | strcmp(*argv + len - 2, "-z") == 0 || |
---|
674 | strcmp(*argv + len - 2, "_z") == 0 || |
---|
675 | strcmp(*argv + len - 2, ".Z") == 0) |
---|
676 | len -= 2; |
---|
677 | else { |
---|
678 | fprintf(stderr, "gun error: no gz type on %s--skipping\n", |
---|
679 | *argv); |
---|
680 | continue; |
---|
681 | } |
---|
682 | outname = malloc(len + 1); |
---|
683 | if (outname == NULL) { |
---|
684 | fprintf(stderr, "gun out of memory error--aborting\n"); |
---|
685 | ret = 1; |
---|
686 | break; |
---|
687 | } |
---|
688 | memcpy(outname, *argv, len); |
---|
689 | outname[len] = 0; |
---|
690 | } |
---|
691 | ret = gunzip(&strm, *argv, outname, test); |
---|
692 | if (outname != NULL) free(outname); |
---|
693 | if (ret) break; |
---|
694 | } while (argv++, --argc); |
---|
695 | else |
---|
696 | ret = gunzip(&strm, NULL, NULL, test); |
---|
697 | |
---|
698 | /* clean up */ |
---|
699 | inflateBackEnd(&strm); |
---|
700 | return ret; |
---|
701 | } |
---|