1 files changed, 551 insertions, 0 deletions

diff --git a/libtar/extract.c b/libtar/extract.c
new file mode 100644
index 000000000..554428715
--- /dev/null
+++ b/libtar/extract.c
@@ -0,0 +1,551 @@
+/*
+**  Copyright 1998-2003 University of Illinois Board of Trustees
+**  Copyright 1998-2003 Mark D. Roth
+**  All rights reserved.
+**
+**  extract.c - libtar code to extract a file from a tar archive
+**
+**  Mark D. Roth <roth@uiuc.edu>
+**  Campus Information Technologies and Educational Services
+**  University of Illinois at Urbana-Champaign
+*/
+
+#include <internal.h>
+
+#include <stdio.h>
+#include <sys/param.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <utime.h>
+
+#define DEBUG
+#ifdef STDC_HEADERS
+# include <stdlib.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#define DEBUG
+
+static int
+tar_set_file_perms(TAR *t, char *realname)
+{
+	mode_t mode;
+	uid_t uid;
+	gid_t gid;
+	struct utimbuf ut;
+	char *filename;
+
+	filename = (realname ? realname : th_get_pathname(t));
+	mode = th_get_mode(t);
+	uid = th_get_uid(t);
+	gid = th_get_gid(t);
+	ut.modtime = ut.actime = th_get_mtime(t);
+
+	/* change owner/group */
+	if (geteuid() == 0)
+#ifdef HAVE_LCHOWN
+		if (lchown(filename, uid, gid) == -1)
+		{
+# ifdef DEBUG
+			fprintf(stderr, "lchown(\"%s\", %d, %d): %s\n",
+				filename, uid, gid, strerror(errno));
+# endif
+#else /* ! HAVE_LCHOWN */
+		if (!TH_ISSYM(t) && chown(filename, uid, gid) == -1)
+		{
+# ifdef DEBUG
+			fprintf(stderr, "chown(\"%s\", %d, %d): %s\n",
+				filename, uid, gid, strerror(errno));
+# endif
+#endif /* HAVE_LCHOWN */
+			return -1;
+		}
+
+	/* change access/modification time */
+	if (!TH_ISSYM(t) && utime(filename, &ut) == -1)
+	{
+#ifdef DEBUG
+		perror("utime()");
+#endif
+		return -1;
+	}
+
+	/* change permissions */
+	if (!TH_ISSYM(t) && chmod(filename, mode) == -1)
+	{
+#ifdef DEBUG
+		perror("chmod()");
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+
+/* switchboard */
+int
+tar_extract_file(TAR *t, char *realname)
+{
+	int i;
+	char *lnp;
+	int pathname_len;
+	int realname_len;
+	
+	if (t->options & TAR_NOOVERWRITE)
+	{
+		struct stat s;
+
+		if (lstat(realname, &s) == 0 || errno != ENOENT)
+		{
+			errno = EEXIST;
+			return -1;
+		}
+	}
+
+	if (TH_ISDIR(t))
+	{
+		i = tar_extract_dir(t, realname);
+		if (i == 1)
+			i = 0;
+	}
+	else if (TH_ISLNK(t)) {
+		printf("link\n");
+		i = tar_extract_hardlink(t, realname);
+	}
+	else if (TH_ISSYM(t)) {
+		printf("sym\n");
+		i = tar_extract_symlink(t, realname);
+	}
+	else if (TH_ISCHR(t)) {
+		printf("chr\n");
+		i = tar_extract_chardev(t, realname);
+	}
+	else if (TH_ISBLK(t)) {
+		printf("blk\n");
+		i = tar_extract_blockdev(t, realname);
+	}
+	else if (TH_ISFIFO(t)) {
+		printf("fifo\n");
+		i = tar_extract_fifo(t, realname);
+	}
+	else /* if (TH_ISREG(t)) */ {
+		printf("reg\n");
+		i = tar_extract_regfile(t, realname);
+	}
+
+	if (i != 0) {
+		printf("here i: %d\n", i);
+		return i;
+	}
+
+	i = tar_set_file_perms(t, realname);
+	if (i != 0) {
+		printf("i: %d\n", i);
+		return i;
+	}
+/*
+	pathname_len = strlen(th_get_pathname(t)) + 1;
+	realname_len = strlen(realname) + 1;
+	lnp = (char *)calloc(1, pathname_len + realname_len);
+	if (lnp == NULL)
+		return -1;
+	strcpy(&lnp[0], th_get_pathname(t));
+	strcpy(&lnp[pathname_len], realname);
+#ifdef DEBUG
+	printf("tar_extract_file(): calling libtar_hash_add(): key=\"%s\", "
+	       "value=\"%s\"\n", th_get_pathname(t), realname);
+#endif
+	if (libtar_hash_add(t->h, lnp) != 0)
+		return -1;
+	free(lnp);
+*/
+	return 0;
+}
+
+
+/* extract regular file */
+int
+tar_extract_regfile(TAR *t, char *realname)
+{
+	mode_t mode;
+	size_t size;
+	uid_t uid;
+	gid_t gid;
+	int fdout;
+	int i, k;
+	char buf[T_BLOCKSIZE];
+	char *filename;
+
+	fflush(NULL);
+#ifdef DEBUG
+	printf("==> tar_extract_regfile(t=0x%lx, realname=\"%s\")\n", t,
+	       realname);
+#endif
+
+	if (!TH_ISREG(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	mode = th_get_mode(t);
+	size = th_get_size(t);
+	uid = th_get_uid(t);
+	gid = th_get_gid(t);
+
+	if (mkdirhier(dirname(filename)) == -1)
+		return -1;
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (mode %04o, uid %d, gid %d, %d bytes)\n",
+	       filename, mode, uid, gid, size);
+#endif
+	fdout = open(filename, O_WRONLY | O_CREAT | O_TRUNC
+#ifdef O_BINARY
+		     | O_BINARY
+#endif
+		    , 0666);
+	if (fdout == -1)
+	{
+#ifdef DEBUG
+		perror("open()");
+#endif
+		return -1;
+	}
+
+#if 0
+	/* change the owner.  (will only work if run as root) */
+	if (fchown(fdout, uid, gid) == -1 && errno != EPERM)
+	{
+#ifdef DEBUG
+		perror("fchown()");
+#endif
+		return -1;
+	}
+
+	/* make sure the mode isn't inheritted from a file we're overwriting */
+	if (fchmod(fdout, mode & 07777) == -1)
+	{
+#ifdef DEBUG
+		perror("fchmod()");
+#endif
+		return -1;
+	}
+#endif
+
+	/* extract the file */
+	for (i = size; i > 0; i -= T_BLOCKSIZE)
+	{
+		k = tar_block_read(t, buf);
+		if (k != T_BLOCKSIZE)
+		{
+			if (k != -1)
+				errno = EINVAL;
+			return -1;
+		}
+
+		/* write block to output file */
+		if (write(fdout, buf,
+			  ((i > T_BLOCKSIZE) ? T_BLOCKSIZE : i)) == -1)
+			return -1;
+	}
+
+	/* close output file */
+	if (close(fdout) == -1)
+		return -1;
+
+#ifdef DEBUG
+	printf("### done extracting %s\n", filename);
+#endif
+
+	return 0;
+}
+
+
+/* skip regfile */
+int
+tar_skip_regfile(TAR *t)
+{
+	int i, k;
+	size_t size;
+	char buf[T_BLOCKSIZE];
+
+	if (!TH_ISREG(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	size = th_get_size(t);
+	for (i = size; i > 0; i -= T_BLOCKSIZE)
+	{
+		k = tar_block_read(t, buf);
+		if (k != T_BLOCKSIZE)
+		{
+			if (k != -1)
+				errno = EINVAL;
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+
+/* hardlink */
+int
+tar_extract_hardlink(TAR * t, char *realname)
+{
+	char *filename;
+	char *linktgt = NULL;
+	char *lnp;
+	libtar_hashptr_t hp;
+
+	if (!TH_ISLNK(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	if (mkdirhier(dirname(filename)) == -1)
+		return -1;
+	libtar_hashptr_reset(&hp);
+	if (libtar_hash_getkey(t->h, &hp, th_get_linkname(t),
+			       (libtar_matchfunc_t)libtar_str_match) != 0)
+	{
+		lnp = (char *)libtar_hashptr_data(&hp);
+		linktgt = &lnp[strlen(lnp) + 1];
+	}
+	else
+		linktgt = th_get_linkname(t);
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (link to %s)\n", filename, linktgt);
+#endif
+	if (link(linktgt, filename) == -1)
+	{
+#ifdef DEBUG
+		perror("link()");
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+
+/* symlink */
+int
+tar_extract_symlink(TAR *t, char *realname)
+{
+	char *filename;
+	
+	if (!TH_ISSYM(t))
+	{
+		printf("not a sym\n");
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	printf("file: %s\n", filename);
+	if (mkdirhier(dirname(filename)) == -1) {
+		printf("mkdirhier\n");
+		return -1;
+	}
+
+	if (unlink(filename) == -1 && errno != ENOENT) {
+		printf("unlink\n");
+		return -1;
+	}
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (symlink to %s)\n",
+	       filename, th_get_linkname(t));
+#endif
+	if (symlink(th_get_linkname(t), filename) == -1)
+	{
+#ifdef DEBUG
+		perror("symlink()");
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+
+/* character device */
+int
+tar_extract_chardev(TAR *t, char *realname)
+{
+	mode_t mode;
+	unsigned long devmaj, devmin;
+	char *filename;
+
+	if (!TH_ISCHR(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	mode = th_get_mode(t);
+	devmaj = th_get_devmajor(t);
+	devmin = th_get_devminor(t);
+
+	if (mkdirhier(dirname(filename)) == -1)
+		return -1;
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (character device %ld,%ld)\n",
+	       filename, devmaj, devmin);
+#endif
+	if (mknod(filename, mode | S_IFCHR,
+		  compat_makedev(devmaj, devmin)) == -1)
+	{
+#ifdef DEBUG
+		perror("mknod()");
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+
+/* block device */
+int
+tar_extract_blockdev(TAR *t, char *realname)
+{
+	mode_t mode;
+	unsigned long devmaj, devmin;
+	char *filename;
+
+	if (!TH_ISBLK(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	mode = th_get_mode(t);
+	devmaj = th_get_devmajor(t);
+	devmin = th_get_devminor(t);
+
+	if (mkdirhier(dirname(filename)) == -1)
+		return -1;
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (block device %ld,%ld)\n",
+	       filename, devmaj, devmin);
+#endif
+	if (mknod(filename, mode | S_IFBLK,
+		  compat_makedev(devmaj, devmin)) == -1)
+	{
+#ifdef DEBUG
+		perror("mknod()");
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+
+/* directory */
+int
+tar_extract_dir(TAR *t, char *realname)
+{
+	mode_t mode;
+	char *filename;
+	printf("filename: %s\n", filename);
+	if (!TH_ISDIR(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	mode = th_get_mode(t);
+
+	if (mkdirhier(dirname(filename)) == -1)
+		return -1;
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (mode %04o, directory)\n", filename,
+	       mode);
+#endif
+	if (mkdir(filename, mode) == -1)
+	{
+		if (errno == EEXIST)
+		{
+			if (chmod(filename, mode) == -1)
+			{
+#ifdef DEBUG
+				perror("chmod()");
+#endif
+				return -1;
+			}
+			else
+			{
+#ifdef DEBUG
+				puts("  *** using existing directory");
+#endif
+				return 1;
+			}
+		}
+		else
+		{
+#ifdef DEBUG
+			perror("mkdir()");
+#endif
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+
+/* FIFO */
+int
+tar_extract_fifo(TAR *t, char *realname)
+{
+	mode_t mode;
+	char *filename;
+
+	if (!TH_ISFIFO(t))
+	{
+		errno = EINVAL;
+		return -1;
+	}
+
+	filename = (realname ? realname : th_get_pathname(t));
+	mode = th_get_mode(t);
+
+	if (mkdirhier(dirname(filename)) == -1)
+		return -1;
+
+#ifdef DEBUG
+	printf("  ==> extracting: %s (fifo)\n", filename);
+#endif
+	if (mkfifo(filename, mode) == -1)
+	{
+#ifdef DEBUG
+		perror("mkfifo()");
+#endif
+		return -1;
+	}
+
+	return 0;
+}
+
+