tar: Add support for -z and -j by invoking external programs

Only extraction is supported at the moment.
This commit is contained in:
sin 2015-01-26 15:07:42 +00:00
parent d00d73fd4a
commit 7fbb858bcd

254
tar.c
View File

@ -1,13 +1,14 @@
/* See LICENSE file for copyright and license details. */
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <grp.h>
#include <limits.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
#include "util.h"
@ -52,104 +53,40 @@ static FILE *tarfile;
static ino_t tarinode;
static dev_t tardev;
static int mflag = 0;
static int mflag;
static char filtermode;
static void
usage(void)
static FILE *
decomp(FILE *fp)
{
eprintf("usage: tar [-f tarfile] [-C dir] [-]x[m]|t\n"
" tar [-f tarfile] [-C dir] [-]c dir\n"
" tar [-C dir] cf tarfile dir\n"
" tar [-C dir] x[m]|tf tarfile\n");
}
int fds[2];
pid_t pid;
int
main(int argc, char *argv[])
{
struct stat st;
char *file = NULL, *dir = ".", *ap;
char mode = '\0';
if (pipe(fds) < 0)
eprintf("pipe:");
ARGBEGIN {
case 'x':
case 'c':
case 't':
if (mode)
usage();
mode = ARGC();
break;
case 'C':
dir = EARGF(usage());
break;
case 'f':
file = EARGF(usage());
break;
case 'm':
mflag = 1;
break;
default:
usage();
} ARGEND;
pid = fork();
if (pid < 0) {
eprintf("fork:");
} else if (!pid) {
dup2(fileno(fp), 0);
dup2(fds[1], 1);
close(fds[0]);
close(fds[1]);
if (!mode) {
if (argc < 1)
usage();
for (ap = argv[0]; *ap; ap++) {
switch (*ap) {
case 'x':
case 'c':
case 't':
if (mode)
usage();
mode = *ap;
break;
case 'f':
if (argc < 2)
usage();
argc--, argv++;
file = argv[0];
break;
case 'C':
if (argc < 2)
usage();
argc--, argv++;
dir = argv[0];
break;
case 'm':
mflag = 1;
break;
default:
usage();
}
switch (filtermode) {
case 'j':
execlp("bzip2", "bzip2", "-cd", (char *)0);
eprintf("execlp bzip2:");
case 'z':
execlp("gzip", "gzip", "-cdf", (char *)0);
eprintf("execlp gzip:");
break;
}
argc--, argv++;
}
if (!mode || argc != (mode == 'c'))
usage();
if (file) {
tarfile = fopen(file, (mode == 'c') ? "wb" : "rb");
if (!tarfile)
eprintf("tar: open '%s':", file);
if (lstat(file, &st) < 0)
eprintf("tar: stat '%s':", file);
tarinode = st.st_ino;
tardev = st.st_dev;
} else {
tarfile = (mode == 'c') ? stdout : stdin;
}
chdir(dir);
if (mode == 'c') {
c(argv[0]);
} else {
xt((mode == 'x') ? unarchive : print);
}
return 0;
close(fds[1]);
return fdopen(fds[0], "r");
}
static void
@ -330,3 +267,134 @@ xt(int (*fn)(char*, int, char[Blksiz]))
fn(fname, strtol(h->size, 0, 8), b);
}
}
static void
usage(void)
{
eprintf("usage: tar [-f tarfile] [-C dir] [-]j|z [-]x[m]|t\n"
" tar [-f tarfile] [-C dir] [-]c dir\n"
" tar [-C dir] cf tarfile dir\n"
" tar [-C dir] j|z x[m]|tf tarfile\n");
}
int
main(int argc, char *argv[])
{
struct stat st;
char *file = NULL, *dir = ".", *ap;
char mode = '\0';
FILE *fp;
ARGBEGIN {
case 'x':
case 'c':
case 't':
if (mode)
usage();
mode = ARGC();
break;
case 'C':
dir = EARGF(usage());
break;
case 'f':
file = EARGF(usage());
break;
case 'm':
mflag = 1;
break;
case 'j':
case 'z':
if (filtermode)
usage();
filtermode = ARGC();
break;
default:
usage();
} ARGEND;
if (!mode) {
if (argc < 1)
usage();
for (ap = argv[0]; *ap; ap++) {
switch (*ap) {
case 'x':
case 'c':
case 't':
if (mode)
usage();
mode = *ap;
break;
case 'f':
if (argc < 2)
usage();
argc--, argv++;
file = argv[0];
break;
case 'C':
if (argc < 2)
usage();
argc--, argv++;
dir = argv[0];
break;
case 'm':
mflag = 1;
break;
case 'j':
case 'z':
if (filtermode)
usage();
filtermode = *ap;
break;
default:
usage();
}
}
argc--, argv++;
}
if (!mode || argc != (mode == 'c'))
usage();
switch (mode) {
case 'c':
if (file) {
if (!(fp = fopen(file, "wb")))
eprintf("fopen %s:", file);
if (lstat(file, &st) < 0)
eprintf("tar: stat '%s':", file);
tarinode = st.st_ino;
tardev = st.st_dev;
tarfile = fp;
} else {
tarfile = stdout;
}
chdir(dir);
c(argv[0]);
break;
case 't':
case 'x':
if (file) {
if (!(fp = fopen(file, "rb")))
eprintf("fopen %s:", file);
} else {
fp = stdin;
}
switch (filtermode) {
case 'j':
case 'z':
tarfile = decomp(fp);
break;
default:
tarfile = fp;
break;
}
chdir(dir);
xt(mode == 'x' ? unarchive : print);
break;
}
return 0;
}