You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
320 lines
8.0 KiB
320 lines
8.0 KiB
/* minigzip.c -- simulate gzip using the zlib compression library |
|
* Copyright (C) 1995-2002 Jean-loup Gailly. |
|
* For conditions of distribution and use, see copyright notice in zlib.h |
|
*/ |
|
|
|
/* |
|
* minigzip is a minimal implementation of the gzip utility. This is |
|
* only an example of using zlib and isn't meant to replace the |
|
* full-featured gzip. No attempt is made to deal with file systems |
|
* limiting names to 14 or 8+3 characters, etc... Error checking is |
|
* very limited. So use minigzip only for testing; use gzip for the |
|
* real thing. On MSDOS, use only on file names without extension |
|
* or in pipe mode. |
|
*/ |
|
|
|
/* @(#) $Id$ */ |
|
|
|
#include <stdio.h> |
|
#include "zlib.h" |
|
|
|
#ifdef STDC |
|
# include <string.h> |
|
# include <stdlib.h> |
|
#else |
|
extern void exit OF((int)); |
|
#endif |
|
|
|
#ifdef USE_MMAP |
|
# include <sys/types.h> |
|
# include <sys/mman.h> |
|
# include <sys/stat.h> |
|
#endif |
|
|
|
#if defined(MSDOS) || defined(OS2) || defined(WIN32) |
|
# include <fcntl.h> |
|
# include <io.h> |
|
# define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY) |
|
#else |
|
# define SET_BINARY_MODE(file) |
|
#endif |
|
|
|
#ifdef VMS |
|
# define unlink delete |
|
# define GZ_SUFFIX "-gz" |
|
#endif |
|
#ifdef RISCOS |
|
# define unlink remove |
|
# define GZ_SUFFIX "-gz" |
|
# define fileno(file) file->__file |
|
#endif |
|
#if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os |
|
# include <unix.h> /* for fileno */ |
|
#endif |
|
|
|
#ifndef WIN32 /* unlink already in stdio.h for WIN32 */ |
|
extern int unlink OF((const char *)); |
|
#endif |
|
|
|
#ifndef GZ_SUFFIX |
|
# define GZ_SUFFIX ".gz" |
|
#endif |
|
#define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1) |
|
|
|
#define BUFLEN 16384 |
|
#define MAX_NAME_LEN 1024 |
|
|
|
#ifdef MAXSEG_64K |
|
# define local static |
|
/* Needed for systems with limitation on stack size. */ |
|
#else |
|
# define local |
|
#endif |
|
|
|
char *prog; |
|
|
|
void error OF((const char *msg)); |
|
void gz_compress OF((FILE *in, gzFile out)); |
|
#ifdef USE_MMAP |
|
int gz_compress_mmap OF((FILE *in, gzFile out)); |
|
#endif |
|
void gz_uncompress OF((gzFile in, FILE *out)); |
|
void file_compress OF((char *file, char *mode)); |
|
void file_uncompress OF((char *file)); |
|
int main OF((int argc, char *argv[])); |
|
|
|
/* =========================================================================== |
|
* Display error message and exit |
|
*/ |
|
void error(msg) |
|
const char *msg; |
|
{ |
|
fprintf(stderr, "%s: %s\n", prog, msg); |
|
exit(1); |
|
} |
|
|
|
/* =========================================================================== |
|
* Compress input to output then close both files. |
|
*/ |
|
|
|
void gz_compress(in, out) |
|
FILE *in; |
|
gzFile out; |
|
{ |
|
local char buf[BUFLEN]; |
|
int len; |
|
int err; |
|
|
|
#ifdef USE_MMAP |
|
/* Try first compressing with mmap. If mmap fails (minigzip used in a |
|
* pipe), use the normal fread loop. |
|
*/ |
|
if (gz_compress_mmap(in, out) == Z_OK) return; |
|
#endif |
|
for (;;) { |
|
len = fread(buf, 1, sizeof(buf), in); |
|
if (ferror(in)) { |
|
perror("fread"); |
|
exit(1); |
|
} |
|
if (len == 0) break; |
|
|
|
if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err)); |
|
} |
|
fclose(in); |
|
if (gzclose(out) != Z_OK) error("failed gzclose"); |
|
} |
|
|
|
#ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */ |
|
|
|
/* Try compressing the input file at once using mmap. Return Z_OK if |
|
* if success, Z_ERRNO otherwise. |
|
*/ |
|
int gz_compress_mmap(in, out) |
|
FILE *in; |
|
gzFile out; |
|
{ |
|
int len; |
|
int err; |
|
int ifd = fileno(in); |
|
caddr_t buf; /* mmap'ed buffer for the entire input file */ |
|
off_t buf_len; /* length of the input file */ |
|
struct stat sb; |
|
|
|
/* Determine the size of the file, needed for mmap: */ |
|
if (fstat(ifd, &sb) < 0) return Z_ERRNO; |
|
buf_len = sb.st_size; |
|
if (buf_len <= 0) return Z_ERRNO; |
|
|
|
/* Now do the actual mmap: */ |
|
buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0); |
|
if (buf == (caddr_t)(-1)) return Z_ERRNO; |
|
|
|
/* Compress the whole file at once: */ |
|
len = gzwrite(out, (char *)buf, (unsigned)buf_len); |
|
|
|
if (len != (int)buf_len) error(gzerror(out, &err)); |
|
|
|
munmap(buf, buf_len); |
|
fclose(in); |
|
if (gzclose(out) != Z_OK) error("failed gzclose"); |
|
return Z_OK; |
|
} |
|
#endif /* USE_MMAP */ |
|
|
|
/* =========================================================================== |
|
* Uncompress input to output then close both files. |
|
*/ |
|
void gz_uncompress(in, out) |
|
gzFile in; |
|
FILE *out; |
|
{ |
|
local char buf[BUFLEN]; |
|
int len; |
|
int err; |
|
|
|
for (;;) { |
|
len = gzread(in, buf, sizeof(buf)); |
|
if (len < 0) error (gzerror(in, &err)); |
|
if (len == 0) break; |
|
|
|
if ((int)fwrite(buf, 1, (unsigned)len, out) != len) { |
|
error("failed fwrite"); |
|
} |
|
} |
|
if (fclose(out)) error("failed fclose"); |
|
|
|
if (gzclose(in) != Z_OK) error("failed gzclose"); |
|
} |
|
|
|
|
|
/* =========================================================================== |
|
* Compress the given file: create a corresponding .gz file and remove the |
|
* original. |
|
*/ |
|
void file_compress(file, mode) |
|
char *file; |
|
char *mode; |
|
{ |
|
local char outfile[MAX_NAME_LEN]; |
|
FILE *in; |
|
gzFile out; |
|
|
|
strcpy(outfile, file); |
|
strcat(outfile, GZ_SUFFIX); |
|
|
|
in = fopen(file, "rb"); |
|
if (in == NULL) { |
|
perror(file); |
|
exit(1); |
|
} |
|
out = gzopen(outfile, mode); |
|
if (out == NULL) { |
|
fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile); |
|
exit(1); |
|
} |
|
gz_compress(in, out); |
|
|
|
unlink(file); |
|
} |
|
|
|
|
|
/* =========================================================================== |
|
* Uncompress the given file and remove the original. |
|
*/ |
|
void file_uncompress(file) |
|
char *file; |
|
{ |
|
local char buf[MAX_NAME_LEN]; |
|
char *infile, *outfile; |
|
FILE *out; |
|
gzFile in; |
|
int len = strlen(file); |
|
|
|
strcpy(buf, file); |
|
|
|
if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) { |
|
infile = file; |
|
outfile = buf; |
|
outfile[len-3] = '\0'; |
|
} else { |
|
outfile = file; |
|
infile = buf; |
|
strcat(infile, GZ_SUFFIX); |
|
} |
|
in = gzopen(infile, "rb"); |
|
if (in == NULL) { |
|
fprintf(stderr, "%s: can't gzopen %s\n", prog, infile); |
|
exit(1); |
|
} |
|
out = fopen(outfile, "wb"); |
|
if (out == NULL) { |
|
perror(file); |
|
exit(1); |
|
} |
|
|
|
gz_uncompress(in, out); |
|
|
|
unlink(infile); |
|
} |
|
|
|
|
|
/* =========================================================================== |
|
* Usage: minigzip [-d] [-f] [-h] [-1 to -9] [files...] |
|
* -d : decompress |
|
* -f : compress with Z_FILTERED |
|
* -h : compress with Z_HUFFMAN_ONLY |
|
* -1 to -9 : compression level |
|
*/ |
|
|
|
int main(argc, argv) |
|
int argc; |
|
char *argv[]; |
|
{ |
|
int uncompr = 0; |
|
gzFile file; |
|
char outmode[20]; |
|
|
|
strcpy(outmode, "wb6 "); |
|
|
|
prog = argv[0]; |
|
argc--, argv++; |
|
|
|
while (argc > 0) { |
|
if (strcmp(*argv, "-d") == 0) |
|
uncompr = 1; |
|
else if (strcmp(*argv, "-f") == 0) |
|
outmode[3] = 'f'; |
|
else if (strcmp(*argv, "-h") == 0) |
|
outmode[3] = 'h'; |
|
else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' && |
|
(*argv)[2] == 0) |
|
outmode[2] = (*argv)[1]; |
|
else |
|
break; |
|
argc--, argv++; |
|
} |
|
if (argc == 0) { |
|
SET_BINARY_MODE(stdin); |
|
SET_BINARY_MODE(stdout); |
|
if (uncompr) { |
|
file = gzdopen(fileno(stdin), "rb"); |
|
if (file == NULL) error("can't gzdopen stdin"); |
|
gz_uncompress(file, stdout); |
|
} else { |
|
file = gzdopen(fileno(stdout), outmode); |
|
if (file == NULL) error("can't gzdopen stdout"); |
|
gz_compress(stdin, file); |
|
} |
|
} else { |
|
do { |
|
if (uncompr) { |
|
file_uncompress(*argv); |
|
} else { |
|
file_compress(*argv, outmode); |
|
} |
|
} while (argv++, --argc); |
|
} |
|
exit(0); |
|
return 0; /* to avoid warning */ |
|
}
|
|
|