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Diffstat (limited to 'Utilities/cmtar/extract.c')
| -rw-r--r-- | Utilities/cmtar/extract.c | 561 |
1 files changed, 561 insertions, 0 deletions
diff --git a/Utilities/cmtar/extract.c b/Utilities/cmtar/extract.c new file mode 100644 index 0000000..4314325 --- /dev/null +++ b/Utilities/cmtar/extract.c @@ -0,0 +1,561 @@ +/* +** 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 <libtarint/internal.h> + +#include <stdio.h> +#include <libtar/compat.h> +#include <sys/types.h> +#include <fcntl.h> +#include <errno.h> +#ifdef _MSC_VER +#include <sys/utime.h> +#include <io.h> +#include <direct.h> +#else +#include <utime.h> +#include <sys/param.h> +#endif +#ifdef STDC_HEADERS +# include <stdlib.h> +# include <string.h> +#endif + +#ifdef HAVE_UNISTD_H +# include <unistd.h> +#endif + + +struct linkname +{ + char ln_save[MAXPATHLEN]; + char ln_real[MAXPATHLEN]; +}; +typedef struct linkname linkname_t; + + +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 */ +#ifndef WIN32 + 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; + } + +#endif /* WIN32 */ + + return 0; +} + + +/* switchboard */ +int +tar_extract_file(TAR *t, char *realname) +{ + int i; + linkname_t *lnp; + + if (t->options & TAR_NOOVERWRITE) + { + struct stat s; + +#ifdef WIN32 + if (stat(realname, &s) == 0 || errno != ENOENT) +#else + if (lstat(realname, &s) == 0 || errno != ENOENT) +#endif + { + errno = EEXIST; + return -1; + } + } + + if (TH_ISDIR(t)) + { + i = tar_extract_dir(t, realname); + if (i == 1) + i = 0; + } +#ifndef _WIN32 + else if (TH_ISLNK(t)) + i = tar_extract_hardlink(t, realname); + else if (TH_ISSYM(t)) + i = tar_extract_symlink(t, realname); + else if (TH_ISCHR(t)) + i = tar_extract_chardev(t, realname); + else if (TH_ISBLK(t)) + i = tar_extract_blockdev(t, realname); + else if (TH_ISFIFO(t)) + i = tar_extract_fifo(t, realname); +#endif + else /* if (TH_ISREG(t)) */ + i = tar_extract_regfile(t, realname); + + if (i != 0) + return i; + + i = tar_set_file_perms(t, realname); + if (i != 0) + return i; + + lnp = (linkname_t *)calloc(1, sizeof(linkname_t)); + if (lnp == NULL) + return -1; + strlcpy(lnp->ln_save, th_get_pathname(t), sizeof(lnp->ln_save)); + strlcpy(lnp->ln_real, realname, sizeof(lnp->ln_real)); +#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; + + 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; + +#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; + linkname_t *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 = (linkname_t *)libtar_hashptr_data(&hp); + linktgt = lnp->ln_real; + } + else + linktgt = th_get_linkname(t); + +#ifdef DEBUG + printf(" ==> extracting: %s (link to %s)\n", filename, linktgt); +#endif +#ifndef WIN32 + if (link(linktgt, filename) == -1) +#endif + { +#ifdef DEBUG + perror("link()"); +#endif + return -1; + } + + return 0; +} + + +/* symlink */ +int +tar_extract_symlink(TAR *t, char *realname) +{ + char *filename; + +#ifndef _WIN32 + if (!TH_ISSYM(t)) + { + errno = EINVAL; + return -1; + } +#endif + + filename = (realname ? realname : th_get_pathname(t)); + if (mkdirhier(dirname(filename)) == -1) + return -1; + + if (unlink(filename) == -1 && errno != ENOENT) + return -1; + +#ifdef DEBUG + printf(" ==> extracting: %s (symlink to %s)\n", + filename, th_get_linkname(t)); +#endif +#ifndef WIN32 + if (symlink(th_get_linkname(t), filename) == -1) +#endif + { +#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; + +#ifndef _WIN32 + if (!TH_ISCHR(t)) + { + errno = EINVAL; + return -1; + } +#endif + 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 +#ifndef WIN32 + if (mknod(filename, mode | S_IFCHR, + compat_makedev(devmaj, devmin)) == -1) +#endif + { +#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 +#ifndef WIN32 + if (mknod(filename, mode | S_IFBLK, + compat_makedev(devmaj, devmin)) == -1) +#endif + { +#ifdef DEBUG + perror("mknod()"); +#endif + return -1; + } + + return 0; +} + + +/* directory */ +int +tar_extract_dir(TAR *t, char *realname) +{ + mode_t mode; + char *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 +#ifdef WIN32 + if (mkdir(filename) == -1) +#else + if (mkdir(filename, mode) == -1) +#endif + { + 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 +#ifndef WIN32 + if (mkfifo(filename, mode) == -1) +#endif + { +#ifdef DEBUG + perror("mkfifo()"); +#endif + return -1; + } + + return 0; +} + + |