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Diffstat (limited to 'source4/lib/zlib/examples/gun.c')
| -rw-r--r-- | source4/lib/zlib/examples/gun.c | 693 |
1 files changed, 0 insertions, 693 deletions
diff --git a/source4/lib/zlib/examples/gun.c b/source4/lib/zlib/examples/gun.c deleted file mode 100644 index bfec590a00..0000000000 --- a/source4/lib/zlib/examples/gun.c +++ /dev/null @@ -1,693 +0,0 @@ -/* gun.c -- simple gunzip to give an example of the use of inflateBack() - * Copyright (C) 2003, 2005 Mark Adler - * For conditions of distribution and use, see copyright notice in zlib.h - Version 1.3 12 June 2005 Mark Adler */ - -/* Version history: - 1.0 16 Feb 2003 First version for testing of inflateBack() - 1.1 21 Feb 2005 Decompress concatenated gzip streams - Remove use of "this" variable (C++ keyword) - Fix return value for in() - Improve allocation failure checking - Add typecasting for void * structures - Add -h option for command version and usage - Add a bunch of comments - 1.2 20 Mar 2005 Add Unix compress (LZW) decompression - Copy file attributes from input file to output file - 1.3 12 Jun 2005 Add casts for error messages [Oberhumer] - */ - -/* - gun [ -t ] [ name ... ] - - decompresses the data in the named gzip files. If no arguments are given, - gun will decompress from stdin to stdout. The names must end in .gz, -gz, - .z, -z, _z, or .Z. The uncompressed data will be written to a file name - with the suffix stripped. On success, the original file is deleted. On - failure, the output file is deleted. For most failures, the command will - continue to process the remaining names on the command line. A memory - allocation failure will abort the command. If -t is specified, then the - listed files or stdin will be tested as gzip files for integrity (without - checking for a proper suffix), no output will be written, and no files - will be deleted. - - Like gzip, gun allows concatenated gzip streams and will decompress them, - writing all of the uncompressed data to the output. Unlike gzip, gun allows - an empty file on input, and will produce no error writing an empty output - file. - - gun will also decompress files made by Unix compress, which uses LZW - compression. These files are automatically detected by virtue of their - magic header bytes. Since the end of Unix compress stream is marked by the - end-of-file, they cannot be concantenated. If a Unix compress stream is - encountered in an input file, it is the last stream in that file. - - Like gunzip and uncompress, the file attributes of the orignal compressed - file are maintained in the final uncompressed file, to the extent that the - user permissions allow it. - - On my Mac OS X PowerPC G4, gun is almost twice as fast as gunzip (version - 1.2.4) is on the same file, when gun is linked with zlib 1.2.2. Also the - LZW decompression provided by gun is about twice as fast as the standard - Unix uncompress command. - */ - -/* external functions and related types and constants */ -#include <stdio.h> /* fprintf() */ -#include <stdlib.h> /* malloc(), free() */ -#include <string.h> /* strerror(), strcmp(), strlen(), memcpy() */ -#include <errno.h> /* errno */ -#include <fcntl.h> /* open() */ -#include <unistd.h> /* read(), write(), close(), chown(), unlink() */ -#include <sys/types.h> -#include <sys/stat.h> /* stat(), chmod() */ -#include <utime.h> /* utime() */ -#include "zlib.h" /* inflateBackInit(), inflateBack(), */ - /* inflateBackEnd(), crc32() */ - -/* function declaration */ -#define local static - -/* buffer constants */ -#define SIZE 32768U /* input and output buffer sizes */ -#define PIECE 16384 /* limits i/o chunks for 16-bit int case */ - -/* structure for infback() to pass to input function in() -- it maintains the - input file and a buffer of size SIZE */ -struct ind { - int infile; - unsigned char *inbuf; -}; - -/* Load input buffer, assumed to be empty, and return bytes loaded and a - pointer to them. read() is called until the buffer is full, or until it - returns end-of-file or error. Return 0 on error. */ -local unsigned in(void *in_desc, unsigned char **buf) -{ - int ret; - unsigned len; - unsigned char *next; - struct ind *me = (struct ind *)in_desc; - - next = me->inbuf; - *buf = next; - len = 0; - do { - ret = PIECE; - if ((unsigned)ret > SIZE - len) - ret = (int)(SIZE - len); - ret = (int)read(me->infile, next, ret); - if (ret == -1) { - len = 0; - break; - } - next += ret; - len += ret; - } while (ret != 0 && len < SIZE); - return len; -} - -/* structure for infback() to pass to output function out() -- it maintains the - output file, a running CRC-32 check on the output and the total number of - bytes output, both for checking against the gzip trailer. (The length in - the gzip trailer is stored modulo 2^32, so it's ok if a long is 32 bits and - the output is greater than 4 GB.) */ -struct outd { - int outfile; - int check; /* true if checking crc and total */ - unsigned long crc; - unsigned long total; -}; - -/* Write output buffer and update the CRC-32 and total bytes written. write() - is called until all of the output is written or an error is encountered. - On success out() returns 0. For a write failure, out() returns 1. If the - output file descriptor is -1, then nothing is written. - */ -local int out(void *out_desc, unsigned char *buf, unsigned len) -{ - int ret; - struct outd *me = (struct outd *)out_desc; - - if (me->check) { - me->crc = crc32(me->crc, buf, len); - me->total += len; - } - if (me->outfile != -1) - do { - ret = PIECE; - if ((unsigned)ret > len) - ret = (int)len; - ret = (int)write(me->outfile, buf, ret); - if (ret == -1) - return 1; - buf += ret; - len -= ret; - } while (len != 0); - return 0; -} - -/* next input byte macro for use inside lunpipe() and gunpipe() */ -#define NEXT() (have ? 0 : (have = in(indp, &next)), \ - last = have ? (have--, (int)(*next++)) : -1) - -/* memory for gunpipe() and lunpipe() -- - the first 256 entries of prefix[] and suffix[] are never used, could - have offset the index, but it's faster to waste the memory */ -unsigned char inbuf[SIZE]; /* input buffer */ -unsigned char outbuf[SIZE]; /* output buffer */ -unsigned short prefix[65536]; /* index to LZW prefix string */ -unsigned char suffix[65536]; /* one-character LZW suffix */ -unsigned char match[65280 + 2]; /* buffer for reversed match or gzip - 32K sliding window */ - -/* throw out what's left in the current bits byte buffer (this is a vestigial - aspect of the compressed data format derived from an implementation that - made use of a special VAX machine instruction!) */ -#define FLUSHCODE() \ - do { \ - left = 0; \ - rem = 0; \ - if (chunk > have) { \ - chunk -= have; \ - have = 0; \ - if (NEXT() == -1) \ - break; \ - chunk--; \ - if (chunk > have) { \ - chunk = have = 0; \ - break; \ - } \ - } \ - have -= chunk; \ - next += chunk; \ - chunk = 0; \ - } while (0) - -/* Decompress a compress (LZW) file from indp to outfile. The compress magic - header (two bytes) has already been read and verified. There are have bytes - of buffered input at next. strm is used for passing error information back - to gunpipe(). - - lunpipe() will return Z_OK on success, Z_BUF_ERROR for an unexpected end of - file, read error, or write error (a write error indicated by strm->next_in - not equal to Z_NULL), or Z_DATA_ERROR for invalid input. - */ -local int lunpipe(unsigned have, unsigned char *next, struct ind *indp, - int outfile, z_stream *strm) -{ - int last; /* last byte read by NEXT(), or -1 if EOF */ - int chunk; /* bytes left in current chunk */ - int left; /* bits left in rem */ - unsigned rem; /* unused bits from input */ - int bits; /* current bits per code */ - unsigned code; /* code, table traversal index */ - unsigned mask; /* mask for current bits codes */ - int max; /* maximum bits per code for this stream */ - int flags; /* compress flags, then block compress flag */ - unsigned end; /* last valid entry in prefix/suffix tables */ - unsigned temp; /* current code */ - unsigned prev; /* previous code */ - unsigned final; /* last character written for previous code */ - unsigned stack; /* next position for reversed string */ - unsigned outcnt; /* bytes in output buffer */ - struct outd outd; /* output structure */ - - /* set up output */ - outd.outfile = outfile; - outd.check = 0; - - /* process remainder of compress header -- a flags byte */ - flags = NEXT(); - if (last == -1) - return Z_BUF_ERROR; - if (flags & 0x60) { - strm->msg = (char *)"unknown lzw flags set"; - return Z_DATA_ERROR; - } - max = flags & 0x1f; - if (max < 9 || max > 16) { - strm->msg = (char *)"lzw bits out of range"; - return Z_DATA_ERROR; - } - if (max == 9) /* 9 doesn't really mean 9 */ - max = 10; - flags &= 0x80; /* true if block compress */ - - /* clear table */ - bits = 9; - mask = 0x1ff; - end = flags ? 256 : 255; - - /* set up: get first 9-bit code, which is the first decompressed byte, but - don't create a table entry until the next code */ - if (NEXT() == -1) /* no compressed data is ok */ - return Z_OK; - final = prev = (unsigned)last; /* low 8 bits of code */ - if (NEXT() == -1) /* missing a bit */ - return Z_BUF_ERROR; - if (last & 1) { /* code must be < 256 */ - strm->msg = (char *)"invalid lzw code"; - return Z_DATA_ERROR; - } - rem = (unsigned)last >> 1; /* remaining 7 bits */ - left = 7; - chunk = bits - 2; /* 7 bytes left in this chunk */ - outbuf[0] = (unsigned char)final; /* write first decompressed byte */ - outcnt = 1; - - /* decode codes */ - stack = 0; - for (;;) { - /* if the table will be full after this, increment the code size */ - if (end >= mask && bits < max) { - FLUSHCODE(); - bits++; - mask <<= 1; - mask++; - } - - /* get a code of length bits */ - if (chunk == 0) /* decrement chunk modulo bits */ - chunk = bits; - code = rem; /* low bits of code */ - if (NEXT() == -1) { /* EOF is end of compressed data */ - /* write remaining buffered output */ - if (outcnt && out(&outd, outbuf, outcnt)) { - strm->next_in = outbuf; /* signal write error */ - return Z_BUF_ERROR; - } - return Z_OK; - } - code += (unsigned)last << left; /* middle (or high) bits of code */ - left += 8; - chunk--; - if (bits > left) { /* need more bits */ - if (NEXT() == -1) /* can't end in middle of code */ - return Z_BUF_ERROR; - code += (unsigned)last << left; /* high bits of code */ - left += 8; - chunk--; - } - code &= mask; /* mask to current code length */ - left -= bits; /* number of unused bits */ - rem = (unsigned)last >> (8 - left); /* unused bits from last byte */ - - /* process clear code (256) */ - if (code == 256 && flags) { - FLUSHCODE(); - bits = 9; /* initialize bits and mask */ - mask = 0x1ff; - end = 255; /* empty table */ - continue; /* get next code */ - } - - /* special code to reuse last match */ - temp = code; /* save the current code */ - if (code > end) { - /* Be picky on the allowed code here, and make sure that the code - we drop through (prev) will be a valid index so that random - input does not cause an exception. The code != end + 1 check is - empirically derived, and not checked in the original uncompress - code. If this ever causes a problem, that check could be safely - removed. Leaving this check in greatly improves gun's ability - to detect random or corrupted input after a compress header. - In any case, the prev > end check must be retained. */ - if (code != end + 1 || prev > end) { - strm->msg = (char *)"invalid lzw code"; - return Z_DATA_ERROR; - } - match[stack++] = (unsigned char)final; - code = prev; - } - - /* walk through linked list to generate output in reverse order */ - while (code >= 256) { - match[stack++] = suffix[code]; - code = prefix[code]; - } - match[stack++] = (unsigned char)code; - final = code; - - /* link new table entry */ - if (end < mask) { - end++; - prefix[end] = (unsigned short)prev; - suffix[end] = (unsigned char)final; - } - - /* set previous code for next iteration */ - prev = temp; - - /* write output in forward order */ - while (stack > SIZE - outcnt) { - while (outcnt < SIZE) - outbuf[outcnt++] = match[--stack]; - if (out(&outd, outbuf, outcnt)) { - strm->next_in = outbuf; /* signal write error */ - return Z_BUF_ERROR; - } - outcnt = 0; - } - do { - outbuf[outcnt++] = match[--stack]; - } while (stack); - - /* loop for next code with final and prev as the last match, rem and - left provide the first 0..7 bits of the next code, end is the last - valid table entry */ - } -} - -/* Decompress a gzip file from infile to outfile. strm is assumed to have been - successfully initialized with inflateBackInit(). The input file may consist - of a series of gzip streams, in which case all of them will be decompressed - to the output file. If outfile is -1, then the gzip stream(s) integrity is - checked and nothing is written. - - The return value is a zlib error code: Z_MEM_ERROR if out of memory, - Z_DATA_ERROR if the header or the compressed data is invalid, or if the - trailer CRC-32 check or length doesn't match, Z_BUF_ERROR if the input ends - prematurely or a write error occurs, or Z_ERRNO if junk (not a another gzip - stream) follows a valid gzip stream. - */ -local int gunpipe(z_stream *strm, int infile, int outfile) -{ - int ret, first, last; - unsigned have, flags, len; - unsigned char *next; - struct ind ind, *indp; - struct outd outd; - - /* setup input buffer */ - ind.infile = infile; - ind.inbuf = inbuf; - indp = &ind; - - /* decompress concatenated gzip streams */ - have = 0; /* no input data read in yet */ - first = 1; /* looking for first gzip header */ - strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ - for (;;) { - /* look for the two magic header bytes for a gzip stream */ - if (NEXT() == -1) { - ret = Z_OK; - break; /* empty gzip stream is ok */ - } - if (last != 31 || (NEXT() != 139 && last != 157)) { - strm->msg = (char *)"incorrect header check"; - ret = first ? Z_DATA_ERROR : Z_ERRNO; - break; /* not a gzip or compress header */ - } - first = 0; /* next non-header is junk */ - - /* process a compress (LZW) file -- can't be concatenated after this */ - if (last == 157) { - ret = lunpipe(have, next, indp, outfile, strm); - break; - } - - /* process remainder of gzip header */ - ret = Z_BUF_ERROR; - if (NEXT() != 8) { /* only deflate method allowed */ - if (last == -1) break; - strm->msg = (char *)"unknown compression method"; - ret = Z_DATA_ERROR; - break; - } - flags = NEXT(); /* header flags */ - NEXT(); /* discard mod time, xflgs, os */ - NEXT(); - NEXT(); - NEXT(); - NEXT(); - NEXT(); - if (last == -1) break; - if (flags & 0xe0) { - strm->msg = (char *)"unknown header flags set"; - ret = Z_DATA_ERROR; - break; - } - if (flags & 4) { /* extra field */ - len = NEXT(); - len += (unsigned)(NEXT()) << 8; - if (last == -1) break; - while (len > have) { - len -= have; - have = 0; - if (NEXT() == -1) break; - len--; - } - if (last == -1) break; - have -= len; - next += len; - } - if (flags & 8) /* file name */ - while (NEXT() != 0 && last != -1) - ; - if (flags & 16) /* comment */ - while (NEXT() != 0 && last != -1) - ; - if (flags & 2) { /* header crc */ - NEXT(); - NEXT(); - } - if (last == -1) break; - - /* set up output */ - outd.outfile = outfile; - outd.check = 1; - outd.crc = crc32(0L, Z_NULL, 0); - outd.total = 0; - - /* decompress data to output */ - strm->next_in = next; - strm->avail_in = have; - ret = inflateBack(strm, in, indp, out, &outd); - if (ret != Z_STREAM_END) break; - next = strm->next_in; - have = strm->avail_in; - strm->next_in = Z_NULL; /* so Z_BUF_ERROR means EOF */ - - /* check trailer */ - ret = Z_BUF_ERROR; - if (NEXT() != (outd.crc & 0xff) || - NEXT() != ((outd.crc >> 8) & 0xff) || - NEXT() != ((outd.crc >> 16) & 0xff) || - NEXT() != ((outd.crc >> 24) & 0xff)) { - /* crc error */ - if (last != -1) { - strm->msg = (char *)"incorrect data check"; - ret = Z_DATA_ERROR; - } - break; - } - if (NEXT() != (outd.total & 0xff) || - NEXT() != ((outd.total >> 8) & 0xff) || - NEXT() != ((outd.total >> 16) & 0xff) || - NEXT() != ((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 1.3 (12 Jun 2005)\n"); - fprintf(stderr, "Copyright (c) 2005 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; -} |