summaryrefslogtreecommitdiffstats
path: root/libtar/extract.c
diff options
context:
space:
mode:
Diffstat (limited to '')
-rw-r--r--libtar/extract.c551
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;
+}
+
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-05 23:15:53 +0100