703 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			703 lines
		
	
	
		
			25 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* gun.c -- simple gunzip to give an example of the use of inflateBack()
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|  * Copyright (C) 2003, 2005, 2008, 2010, 2012 Mark Adler
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|  * For conditions of distribution and use, see copyright notice in zlib.h
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|    Version 1.7  12 August 2012  Mark Adler */
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| 
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| /* Version history:
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|    1.0  16 Feb 2003  First version for testing of inflateBack()
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|    1.1  21 Feb 2005  Decompress concatenated gzip streams
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|                      Remove use of "this" variable (C++ keyword)
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|                      Fix return value for in()
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|                      Improve allocation failure checking
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|                      Add typecasting for void * structures
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|                      Add -h option for command version and usage
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|                      Add a bunch of comments
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|    1.2  20 Mar 2005  Add Unix compress (LZW) decompression
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|                      Copy file attributes from input file to output file
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|    1.3  12 Jun 2005  Add casts for error messages [Oberhumer]
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|    1.4   8 Dec 2006  LZW decompression speed improvements
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|    1.5   9 Feb 2008  Avoid warning in latest version of gcc
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|    1.6  17 Jan 2010  Avoid signed/unsigned comparison warnings
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|    1.7  12 Aug 2012  Update for z_const usage in zlib 1.2.8
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|  */
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| 
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| /*
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|    gun [ -t ] [ name ... ]
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| 
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|    decompresses the data in the named gzip files.  If no arguments are given,
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|    gun will decompress from stdin to stdout.  The names must end in .gz, -gz,
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|    .z, -z, _z, or .Z.  The uncompressed data will be written to a file name
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|    with the suffix stripped.  On success, the original file is deleted.  On
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|    failure, the output file is deleted.  For most failures, the command will
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|    continue to process the remaining names on the command line.  A memory
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|    allocation failure will abort the command.  If -t is specified, then the
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|    listed files or stdin will be tested as gzip files for integrity (without
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|    checking for a proper suffix), no output will be written, and no files
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|    will be deleted.
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| 
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|    Like gzip, gun allows concatenated gzip streams and will decompress them,
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|    writing all of the uncompressed data to the output.  Unlike gzip, gun allows
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|    an empty file on input, and will produce no error writing an empty output
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|    file.
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| 
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|    gun will also decompress files made by Unix compress, which uses LZW
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|    compression.  These files are automatically detected by virtue of their
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|    magic header bytes.  Since the end of Unix compress stream is marked by the
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|    end-of-file, they cannot be concantenated.  If a Unix compress stream is
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|    encountered in an input file, it is the last stream in that file.
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| 
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|    Like gunzip and uncompress, the file attributes of the original compressed
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|    file are maintained in the final uncompressed file, to the extent that the
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|    user permissions allow it.
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| 
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|    On my Mac OS X PowerPC G4, gun is almost twice as fast as gunzip (version
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|    1.2.4) is on the same file, when gun is linked with zlib 1.2.2.  Also the
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|    LZW decompression provided by gun is about twice as fast as the standard
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|    Unix uncompress command.
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|  */
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| 
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| /* external functions and related types and constants */
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| #include <stdio.h>          /* fprintf() */
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| #include <stdlib.h>         /* malloc(), free() */
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| #include <string.h>         /* strerror(), strcmp(), strlen(), memcpy() */
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| #include <errno.h>          /* errno */
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| #include <fcntl.h>          /* open() */
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| #include <unistd.h>         /* read(), write(), close(), chown(), unlink() */
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| #include <sys/types.h>
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| #include <sys/stat.h>       /* stat(), chmod() */
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| #include <utime.h>          /* utime() */
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| #include "zlib.h"           /* inflateBackInit(), inflateBack(), */
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|                             /* inflateBackEnd(), crc32() */
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| 
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| /* function declaration */
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| #define local static
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| 
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| /* buffer constants */
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| #define SIZE 32768U         /* input and output buffer sizes */
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| #define PIECE 16384         /* limits i/o chunks for 16-bit int case */
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| 
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| /* structure for infback() to pass to input function in() -- it maintains the
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|    input file and a buffer of size SIZE */
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| struct ind {
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|     int infile;
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|     unsigned char *inbuf;
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| };
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| 
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| /* Load input buffer, assumed to be empty, and return bytes loaded and a
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|    pointer to them.  read() is called until the buffer is full, or until it
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|    returns end-of-file or error.  Return 0 on error. */
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| local unsigned in(void *in_desc, z_const unsigned char **buf)
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| {
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|     int ret;
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|     unsigned len;
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|     unsigned char *next;
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|     struct ind *me = (struct ind *)in_desc;
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| 
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|     next = me->inbuf;
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|     *buf = next;
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|     len = 0;
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|     do {
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|         ret = PIECE;
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|         if ((unsigned)ret > SIZE - len)
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|             ret = (int)(SIZE - len);
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|         ret = (int)read(me->infile, next, ret);
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|         if (ret == -1) {
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|             len = 0;
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|             break;
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|         }
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|         next += ret;
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|         len += ret;
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|     } while (ret != 0 && len < SIZE);
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|     return len;
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| }
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| 
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| /* structure for infback() to pass to output function out() -- it maintains the
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|    output file, a running CRC-32 check on the output and the total number of
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|    bytes output, both for checking against the gzip trailer.  (The length in
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|    the gzip trailer is stored modulo 2^32, so it's ok if a long is 32 bits and
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|    the output is greater than 4 GB.) */
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| struct outd {
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|     int outfile;
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|     int check;                  /* true if checking crc and total */
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|     unsigned long crc;
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|     unsigned long total;
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| };
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| 
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| /* Write output buffer and update the CRC-32 and total bytes written.  write()
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|    is called until all of the output is written or an error is encountered.
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|    On success out() returns 0.  For a write failure, out() returns 1.  If the
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|    output file descriptor is -1, then nothing is written.
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|  */
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| local int out(void *out_desc, unsigned char *buf, unsigned len)
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| {
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|     int ret;
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|     struct outd *me = (struct outd *)out_desc;
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| 
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|     if (me->check) {
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|         me->crc = crc32(me->crc, buf, len);
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|         me->total += len;
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|     }
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|     if (me->outfile != -1)
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|         do {
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|             ret = PIECE;
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|             if ((unsigned)ret > len)
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|                 ret = (int)len;
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|             ret = (int)write(me->outfile, buf, ret);
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|             if (ret == -1)
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|                 return 1;
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|             buf += ret;
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|             len -= ret;
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|         } while (len != 0);
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|     return 0;
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| }
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| 
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| /* next input byte macro for use inside lunpipe() and gunpipe() */
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| #define NEXT() (have ? 0 : (have = in(indp, &next)), \
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|                 last = have ? (have--, (int)(*next++)) : -1)
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| 
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| /* memory for gunpipe() and lunpipe() --
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|    the first 256 entries of prefix[] and suffix[] are never used, could
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|    have offset the index, but it's faster to waste the memory */
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| unsigned char inbuf[SIZE];              /* input buffer */
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| unsigned char outbuf[SIZE];             /* output buffer */
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| unsigned short prefix[65536];           /* index to LZW prefix string */
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| unsigned char suffix[65536];            /* one-character LZW suffix */
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| unsigned char match[65280 + 2];         /* buffer for reversed match or gzip
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|                                            32K sliding window */
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| 
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| /* throw out what's left in the current bits byte buffer (this is a vestigial
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|    aspect of the compressed data format derived from an implementation that
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|    made use of a special VAX machine instruction!) */
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| #define FLUSHCODE() \
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|     do { \
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|         left = 0; \
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|         rem = 0; \
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|         if (chunk > have) { \
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|             chunk -= have; \
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|             have = 0; \
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|             if (NEXT() == -1) \
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|                 break; \
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|             chunk--; \
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|             if (chunk > have) { \
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|                 chunk = have = 0; \
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|                 break; \
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|             } \
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|         } \
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|         have -= chunk; \
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|         next += chunk; \
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|         chunk = 0; \
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|     } while (0)
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| 
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| /* Decompress a compress (LZW) file from indp to outfile.  The compress magic
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|    header (two bytes) has already been read and verified.  There are have bytes
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|    of buffered input at next.  strm is used for passing error information back
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|    to gunpipe().
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| 
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|    lunpipe() will return Z_OK on success, Z_BUF_ERROR for an unexpected end of
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|    file, read error, or write error (a write error indicated by strm->next_in
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|    not equal to Z_NULL), or Z_DATA_ERROR for invalid input.
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|  */
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| local int lunpipe(unsigned have, z_const unsigned char *next, struct ind *indp,
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|                   int outfile, z_stream *strm)
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| {
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|     int last;                   /* last byte read by NEXT(), or -1 if EOF */
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|     unsigned chunk;             /* bytes left in current chunk */
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|     int left;                   /* bits left in rem */
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|     unsigned rem;               /* unused bits from input */
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|     int bits;                   /* current bits per code */
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|     unsigned code;              /* code, table traversal index */
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|     unsigned mask;              /* mask for current bits codes */
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|     int max;                    /* maximum bits per code for this stream */
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|     unsigned flags;             /* compress flags, then block compress flag */
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|     unsigned end;               /* last valid entry in prefix/suffix tables */
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|     unsigned temp;              /* current code */
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|     unsigned prev;              /* previous code */
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|     unsigned final;             /* last character written for previous code */
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|     unsigned stack;             /* next position for reversed string */
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|     unsigned outcnt;            /* bytes in output buffer */
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|     struct outd outd;           /* output structure */
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|     unsigned char *p;
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| 
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|     /* set up output */
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|     outd.outfile = outfile;
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|     outd.check = 0;
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| 
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|     /* process remainder of compress header -- a flags byte */
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|     flags = NEXT();
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|     if (last == -1)
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|         return Z_BUF_ERROR;
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|     if (flags & 0x60) {
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|         strm->msg = (char *)"unknown lzw flags set";
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|         return Z_DATA_ERROR;
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|     }
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|     max = flags & 0x1f;
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|     if (max < 9 || max > 16) {
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|         strm->msg = (char *)"lzw bits out of range";
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|         return Z_DATA_ERROR;
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|     }
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|     if (max == 9)                           /* 9 doesn't really mean 9 */
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|         max = 10;
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|     flags &= 0x80;                          /* true if block compress */
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| 
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|     /* clear table */
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|     bits = 9;
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|     mask = 0x1ff;
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|     end = flags ? 256 : 255;
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| 
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|     /* set up: get first 9-bit code, which is the first decompressed byte, but
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|        don't create a table entry until the next code */
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|     if (NEXT() == -1)                       /* no compressed data is ok */
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|         return Z_OK;
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|     final = prev = (unsigned)last;          /* low 8 bits of code */
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|     if (NEXT() == -1)                       /* missing a bit */
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|         return Z_BUF_ERROR;
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|     if (last & 1) {                         /* code must be < 256 */
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|         strm->msg = (char *)"invalid lzw code";
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|         return Z_DATA_ERROR;
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|     }
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|     rem = (unsigned)last >> 1;              /* remaining 7 bits */
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|     left = 7;
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|     chunk = bits - 2;                       /* 7 bytes left in this chunk */
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|     outbuf[0] = (unsigned char)final;       /* write first decompressed byte */
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|     outcnt = 1;
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| 
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|     /* decode codes */
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|     stack = 0;
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|     for (;;) {
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|         /* if the table will be full after this, increment the code size */
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|         if (end >= mask && bits < max) {
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|             FLUSHCODE();
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|             bits++;
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|             mask <<= 1;
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|             mask++;
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|         }
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| 
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|         /* get a code of length bits */
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|         if (chunk == 0)                     /* decrement chunk modulo bits */
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|             chunk = bits;
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|         code = rem;                         /* low bits of code */
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|         if (NEXT() == -1) {                 /* EOF is end of compressed data */
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|             /* write remaining buffered output */
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|             if (outcnt && out(&outd, outbuf, outcnt)) {
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|                 strm->next_in = outbuf;     /* signal write error */
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|                 return Z_BUF_ERROR;
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|             }
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|             return Z_OK;
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|         }
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|         code += (unsigned)last << left;     /* middle (or high) bits of code */
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|         left += 8;
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|         chunk--;
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|         if (bits > left) {                  /* need more bits */
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|             if (NEXT() == -1)               /* can't end in middle of code */
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|                 return Z_BUF_ERROR;
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|             code += (unsigned)last << left; /* high bits of code */
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|             left += 8;
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|             chunk--;
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|         }
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|         code &= mask;                       /* mask to current code length */
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|         left -= bits;                       /* number of unused bits */
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|         rem = (unsigned)last >> (8 - left); /* unused bits from last byte */
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| 
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|         /* process clear code (256) */
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|         if (code == 256 && flags) {
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|             FLUSHCODE();
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|             bits = 9;                       /* initialize bits and mask */
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|             mask = 0x1ff;
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|             end = 255;                      /* empty table */
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|             continue;                       /* get next code */
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|         }
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| 
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|         /* special code to reuse last match */
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|         temp = code;                        /* save the current code */
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|         if (code > end) {
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|             /* Be picky on the allowed code here, and make sure that the code
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|                we drop through (prev) will be a valid index so that random
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|                input does not cause an exception.  The code != end + 1 check is
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|                empirically derived, and not checked in the original uncompress
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|                code.  If this ever causes a problem, that check could be safely
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|                removed.  Leaving this check in greatly improves gun's ability
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|                to detect random or corrupted input after a compress header.
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|                In any case, the prev > end check must be retained. */
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|             if (code != end + 1 || prev > end) {
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|                 strm->msg = (char *)"invalid lzw code";
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|                 return Z_DATA_ERROR;
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|             }
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|             match[stack++] = (unsigned char)final;
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|             code = prev;
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|         }
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| 
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|         /* walk through linked list to generate output in reverse order */
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|         p = match + stack;
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|         while (code >= 256) {
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|             *p++ = suffix[code];
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|             code = prefix[code];
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|         }
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|         stack = p - match;
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|         match[stack++] = (unsigned char)code;
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|         final = code;
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| 
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|         /* link new table entry */
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|         if (end < mask) {
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|             end++;
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|             prefix[end] = (unsigned short)prev;
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|             suffix[end] = (unsigned char)final;
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|         }
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| 
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|         /* set previous code for next iteration */
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|         prev = temp;
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| 
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|         /* write output in forward order */
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|         while (stack > SIZE - outcnt) {
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|             while (outcnt < SIZE)
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|                 outbuf[outcnt++] = match[--stack];
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|             if (out(&outd, outbuf, outcnt)) {
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|                 strm->next_in = outbuf; /* signal write error */
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|                 return Z_BUF_ERROR;
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|             }
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|             outcnt = 0;
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|         }
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|         p = match + stack;
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|         do {
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|             outbuf[outcnt++] = *--p;
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|         } while (p > match);
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|         stack = 0;
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| 
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|         /* loop for next code with final and prev as the last match, rem and
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|            left provide the first 0..7 bits of the next code, end is the last
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|            valid table entry */
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|     }
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| }
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| 
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| /* Decompress a gzip file from infile to outfile.  strm is assumed to have been
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|    successfully initialized with inflateBackInit().  The input file may consist
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|    of a series of gzip streams, in which case all of them will be decompressed
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|    to the output file.  If outfile is -1, then the gzip stream(s) integrity is
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|    checked and nothing is written.
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| 
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|    The return value is a zlib error code: Z_MEM_ERROR if out of memory,
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|    Z_DATA_ERROR if the header or the compressed data is invalid, or if the
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|    trailer CRC-32 check or length doesn't match, Z_BUF_ERROR if the input ends
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|    prematurely or a write error occurs, or Z_ERRNO if junk (not a another gzip
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|    stream) follows a valid gzip stream.
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|  */
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| local int gunpipe(z_stream *strm, int infile, int outfile)
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| {
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|     int ret, first, last;
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|     unsigned have, flags, len;
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|     z_const unsigned char *next = NULL;
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|     struct ind ind, *indp;
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|     struct outd outd;
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| 
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|     /* setup input buffer */
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|     ind.infile = infile;
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|     ind.inbuf = inbuf;
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|     indp = &ind;
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| 
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|     /* decompress concatenated gzip streams */
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|     have = 0;                               /* no input data read in yet */
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|     first = 1;                              /* looking for first gzip header */
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|     strm->next_in = Z_NULL;                 /* so Z_BUF_ERROR means EOF */
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|     for (;;) {
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|         /* look for the two magic header bytes for a gzip stream */
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|         if (NEXT() == -1) {
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|             ret = Z_OK;
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|             break;                          /* empty gzip stream is ok */
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|         }
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|         if (last != 31 || (NEXT() != 139 && last != 157)) {
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|             strm->msg = (char *)"incorrect header check";
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|             ret = first ? Z_DATA_ERROR : Z_ERRNO;
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|             break;                          /* not a gzip or compress header */
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|         }
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|         first = 0;                          /* next non-header is junk */
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| 
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|         /* process a compress (LZW) file -- can't be concatenated after this */
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|         if (last == 157) {
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|             ret = lunpipe(have, next, indp, outfile, strm);
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|             break;
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|         }
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| 
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|         /* process remainder of gzip header */
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|         ret = Z_BUF_ERROR;
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|         if (NEXT() != 8) {                  /* only deflate method allowed */
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|             if (last == -1) break;
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|             strm->msg = (char *)"unknown compression method";
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|             ret = Z_DATA_ERROR;
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|             break;
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|         }
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|         flags = NEXT();                     /* header flags */
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|         NEXT();                             /* discard mod time, xflgs, os */
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|         NEXT();
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|         NEXT();
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|         NEXT();
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|         NEXT();
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|         NEXT();
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|         if (last == -1) break;
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|         if (flags & 0xe0) {
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|             strm->msg = (char *)"unknown header flags set";
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|             ret = Z_DATA_ERROR;
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|             break;
 | |
|         }
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|         if (flags & 4) {                    /* extra field */
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|             len = NEXT();
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|             len += (unsigned)(NEXT()) << 8;
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|             if (last == -1) break;
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|             while (len > have) {
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|                 len -= have;
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|                 have = 0;
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|                 if (NEXT() == -1) break;
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|                 len--;
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|             }
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|             if (last == -1) break;
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|             have -= len;
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|             next += len;
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|         }
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|         if (flags & 8)                      /* file name */
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|             while (NEXT() != 0 && last != -1)
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|                 ;
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|         if (flags & 16)                     /* comment */
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|             while (NEXT() != 0 && last != -1)
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|                 ;
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|         if (flags & 2) {                    /* header crc */
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|             NEXT();
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|             NEXT();
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|         }
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|         if (last == -1) break;
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| 
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|         /* set up output */
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|         outd.outfile = outfile;
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|         outd.check = 1;
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|         outd.crc = crc32(0L, Z_NULL, 0);
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|         outd.total = 0;
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| 
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|         /* decompress data to output */
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|         strm->next_in = next;
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|         strm->avail_in = have;
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|         ret = inflateBack(strm, in, indp, out, &outd);
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|         if (ret != Z_STREAM_END) break;
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|         next = strm->next_in;
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|         have = strm->avail_in;
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|         strm->next_in = Z_NULL;             /* so Z_BUF_ERROR means EOF */
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| 
 | |
|         /* check trailer */
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|         ret = Z_BUF_ERROR;
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|         if (NEXT() != (int)(outd.crc & 0xff) ||
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|             NEXT() != (int)((outd.crc >> 8) & 0xff) ||
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|             NEXT() != (int)((outd.crc >> 16) & 0xff) ||
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|             NEXT() != (int)((outd.crc >> 24) & 0xff)) {
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|             /* crc error */
 | |
|             if (last != -1) {
 | |
|                 strm->msg = (char *)"incorrect data check";
 | |
|                 ret = Z_DATA_ERROR;
 | |
|             }
 | |
|             break;
 | |
|         }
 | |
|         if (NEXT() != (int)(outd.total & 0xff) ||
 | |
|             NEXT() != (int)((outd.total >> 8) & 0xff) ||
 | |
|             NEXT() != (int)((outd.total >> 16) & 0xff) ||
 | |
|             NEXT() != (int)((outd.total >> 24) & 0xff)) {
 | |
|             /* length error */
 | |
|             if (last != -1) {
 | |
|                 strm->msg = (char *)"incorrect length check";
 | |
|                 ret = Z_DATA_ERROR;
 | |
|             }
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         /* go back and look for another gzip stream */
 | |
|     }
 | |
| 
 | |
|     /* clean up and return */
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| /* Copy file attributes, from -> to, as best we can.  This is best effort, so
 | |
|    no errors are reported.  The mode bits, including suid, sgid, and the sticky
 | |
|    bit are copied (if allowed), the owner's user id and group id are copied
 | |
|    (again if allowed), and the access and modify times are copied. */
 | |
| local void copymeta(char *from, char *to)
 | |
| {
 | |
|     struct stat was;
 | |
|     struct utimbuf when;
 | |
| 
 | |
|     /* get all of from's Unix meta data, return if not a regular file */
 | |
|     if (stat(from, &was) != 0 || (was.st_mode & S_IFMT) != S_IFREG)
 | |
|         return;
 | |
| 
 | |
|     /* set to's mode bits, ignore errors */
 | |
|     (void)chmod(to, was.st_mode & 07777);
 | |
| 
 | |
|     /* copy owner's user and group, ignore errors */
 | |
|     (void)chown(to, was.st_uid, was.st_gid);
 | |
| 
 | |
|     /* copy access and modify times, ignore errors */
 | |
|     when.actime = was.st_atime;
 | |
|     when.modtime = was.st_mtime;
 | |
|     (void)utime(to, &when);
 | |
| }
 | |
| 
 | |
| /* Decompress the file inname to the file outnname, of if test is true, just
 | |
|    decompress without writing and check the gzip trailer for integrity.  If
 | |
|    inname is NULL or an empty string, read from stdin.  If outname is NULL or
 | |
|    an empty string, write to stdout.  strm is a pre-initialized inflateBack
 | |
|    structure.  When appropriate, copy the file attributes from inname to
 | |
|    outname.
 | |
| 
 | |
|    gunzip() returns 1 if there is an out-of-memory error or an unexpected
 | |
|    return code from gunpipe().  Otherwise it returns 0.
 | |
|  */
 | |
| local int gunzip(z_stream *strm, char *inname, char *outname, int test)
 | |
| {
 | |
|     int ret;
 | |
|     int infile, outfile;
 | |
| 
 | |
|     /* open files */
 | |
|     if (inname == NULL || *inname == 0) {
 | |
|         inname = "-";
 | |
|         infile = 0;     /* stdin */
 | |
|     }
 | |
|     else {
 | |
|         infile = open(inname, O_RDONLY, 0);
 | |
|         if (infile == -1) {
 | |
|             fprintf(stderr, "gun cannot open %s\n", inname);
 | |
|             return 0;
 | |
|         }
 | |
|     }
 | |
|     if (test)
 | |
|         outfile = -1;
 | |
|     else if (outname == NULL || *outname == 0) {
 | |
|         outname = "-";
 | |
|         outfile = 1;    /* stdout */
 | |
|     }
 | |
|     else {
 | |
|         outfile = open(outname, O_CREAT | O_TRUNC | O_WRONLY, 0666);
 | |
|         if (outfile == -1) {
 | |
|             close(infile);
 | |
|             fprintf(stderr, "gun cannot create %s\n", outname);
 | |
|             return 0;
 | |
|         }
 | |
|     }
 | |
|     errno = 0;
 | |
| 
 | |
|     /* decompress */
 | |
|     ret = gunpipe(strm, infile, outfile);
 | |
|     if (outfile > 2) close(outfile);
 | |
|     if (infile > 2) close(infile);
 | |
| 
 | |
|     /* interpret result */
 | |
|     switch (ret) {
 | |
|     case Z_OK:
 | |
|     case Z_ERRNO:
 | |
|         if (infile > 2 && outfile > 2) {
 | |
|             copymeta(inname, outname);          /* copy attributes */
 | |
|             unlink(inname);
 | |
|         }
 | |
|         if (ret == Z_ERRNO)
 | |
|             fprintf(stderr, "gun warning: trailing garbage ignored in %s\n",
 | |
|                     inname);
 | |
|         break;
 | |
|     case Z_DATA_ERROR:
 | |
|         if (outfile > 2) unlink(outname);
 | |
|         fprintf(stderr, "gun data error on %s: %s\n", inname, strm->msg);
 | |
|         break;
 | |
|     case Z_MEM_ERROR:
 | |
|         if (outfile > 2) unlink(outname);
 | |
|         fprintf(stderr, "gun out of memory error--aborting\n");
 | |
|         return 1;
 | |
|     case Z_BUF_ERROR:
 | |
|         if (outfile > 2) unlink(outname);
 | |
|         if (strm->next_in != Z_NULL) {
 | |
|             fprintf(stderr, "gun write error on %s: %s\n",
 | |
|                     outname, strerror(errno));
 | |
|         }
 | |
|         else if (errno) {
 | |
|             fprintf(stderr, "gun read error on %s: %s\n",
 | |
|                     inname, strerror(errno));
 | |
|         }
 | |
|         else {
 | |
|             fprintf(stderr, "gun unexpected end of file on %s\n",
 | |
|                     inname);
 | |
|         }
 | |
|         break;
 | |
|     default:
 | |
|         if (outfile > 2) unlink(outname);
 | |
|         fprintf(stderr, "gun internal error--aborting\n");
 | |
|         return 1;
 | |
|     }
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| /* Process the gun command line arguments.  See the command syntax near the
 | |
|    beginning of this source file. */
 | |
| int main(int argc, char **argv)
 | |
| {
 | |
|     int ret, len, test;
 | |
|     char *outname;
 | |
|     unsigned char *window;
 | |
|     z_stream strm;
 | |
| 
 | |
|     /* initialize inflateBack state for repeated use */
 | |
|     window = match;                         /* reuse LZW match buffer */
 | |
|     strm.zalloc = Z_NULL;
 | |
|     strm.zfree = Z_NULL;
 | |
|     strm.opaque = Z_NULL;
 | |
|     ret = inflateBackInit(&strm, 15, window);
 | |
|     if (ret != Z_OK) {
 | |
|         fprintf(stderr, "gun out of memory error--aborting\n");
 | |
|         return 1;
 | |
|     }
 | |
| 
 | |
|     /* decompress each file to the same name with the suffix removed */
 | |
|     argc--;
 | |
|     argv++;
 | |
|     test = 0;
 | |
|     if (argc && strcmp(*argv, "-h") == 0) {
 | |
|         fprintf(stderr, "gun 1.6 (17 Jan 2010)\n");
 | |
|         fprintf(stderr, "Copyright (C) 2003-2010 Mark Adler\n");
 | |
|         fprintf(stderr, "usage: gun [-t] [file1.gz [file2.Z ...]]\n");
 | |
|         return 0;
 | |
|     }
 | |
|     if (argc && strcmp(*argv, "-t") == 0) {
 | |
|         test = 1;
 | |
|         argc--;
 | |
|         argv++;
 | |
|     }
 | |
|     if (argc)
 | |
|         do {
 | |
|             if (test)
 | |
|                 outname = NULL;
 | |
|             else {
 | |
|                 len = (int)strlen(*argv);
 | |
|                 if (strcmp(*argv + len - 3, ".gz") == 0 ||
 | |
|                     strcmp(*argv + len - 3, "-gz") == 0)
 | |
|                     len -= 3;
 | |
|                 else if (strcmp(*argv + len - 2, ".z") == 0 ||
 | |
|                     strcmp(*argv + len - 2, "-z") == 0 ||
 | |
|                     strcmp(*argv + len - 2, "_z") == 0 ||
 | |
|                     strcmp(*argv + len - 2, ".Z") == 0)
 | |
|                     len -= 2;
 | |
|                 else {
 | |
|                     fprintf(stderr, "gun error: no gz type on %s--skipping\n",
 | |
|                             *argv);
 | |
|                     continue;
 | |
|                 }
 | |
|                 outname = malloc(len + 1);
 | |
|                 if (outname == NULL) {
 | |
|                     fprintf(stderr, "gun out of memory error--aborting\n");
 | |
|                     ret = 1;
 | |
|                     break;
 | |
|                 }
 | |
|                 memcpy(outname, *argv, len);
 | |
|                 outname[len] = 0;
 | |
|             }
 | |
|             ret = gunzip(&strm, *argv, outname, test);
 | |
|             if (outname != NULL) free(outname);
 | |
|             if (ret) break;
 | |
|         } while (argv++, --argc);
 | |
|     else
 | |
|         ret = gunzip(&strm, NULL, NULL, test);
 | |
| 
 | |
|     /* clean up */
 | |
|     inflateBackEnd(&strm);
 | |
|     return ret;
 | |
| }
 | 
