342 lines
8.2 KiB
C
342 lines
8.2 KiB
C
/* 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.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#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;
|
|
|
|
if (strlen(file) + strlen(GZ_SUFFIX) >= sizeof(outfile)) {
|
|
fprintf(stderr, "%s: filename too long\n", prog);
|
|
exit(1);
|
|
}
|
|
|
|
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;
|
|
size_t len = strlen(file);
|
|
|
|
if (len + strlen(GZ_SUFFIX) >= sizeof(buf)) {
|
|
fprintf(stderr, "%s: filename too long\n", prog);
|
|
exit(1);
|
|
}
|
|
|
|
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 *bname, outmode[20];
|
|
|
|
strcpy(outmode, "wb6 ");
|
|
|
|
prog = argv[0];
|
|
bname = strrchr(argv[0], '/');
|
|
if (bname)
|
|
bname++;
|
|
else
|
|
bname = argv[0];
|
|
argc--, argv++;
|
|
|
|
if (!strcmp(bname, "gunzip") || !strcmp(bname, "zcat"))
|
|
uncompr = 1;
|
|
|
|
while (argc > 0) {
|
|
if (strcmp(*argv, "-c") == 0)
|
|
; /* Just for compatibility with gzip */
|
|
else 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 */
|
|
}
|