This is primarily to allow deb_extract to be independent of the tar applet.
TODO: This function and its conterpart in tar.c should be merged
diff --git a/libbb/untar.c b/libbb/untar.c
new file mode 100644
index 0000000..1542e39
--- /dev/null
+++ b/libbb/untar.c
@@ -0,0 +1,200 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * NOTE: This is used by deb_extract to avoid calling the whole tar applet.
+ * Its functionality should be merged with tar to avoid duplication
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "libbb.h"
+
+extern int untar(FILE *src_tar_file, int untar_function, char *base_path)
+{
+ typedef struct raw_tar_header {
+ char name[100]; /* 0-99 */
+ char mode[8]; /* 100-107 */
+ char uid[8]; /* 108-115 */
+ char gid[8]; /* 116-123 */
+ char size[12]; /* 124-135 */
+ char mtime[12]; /* 136-147 */
+ char chksum[8]; /* 148-155 */
+ char typeflag; /* 156-156 */
+ char linkname[100]; /* 157-256 */
+ char magic[6]; /* 257-262 */
+ char version[2]; /* 263-264 */
+ char uname[32]; /* 265-296 */
+ char gname[32]; /* 297-328 */
+ char devmajor[8]; /* 329-336 */
+ char devminor[8]; /* 337-344 */
+ char prefix[155]; /* 345-499 */
+ char padding[12]; /* 500-512 */
+ } raw_tar_header_t;
+
+// const int dpkg_deb_contents = 1;
+// const int dpkg_deb_control = 2;
+// const int dpkg_deb_info = 4;
+ const int untar_extract = 8;
+// const int dpkg_deb_verbose_extract = 16;
+// const int dpkg_deb_list = 32;
+
+ raw_tar_header_t raw_tar_header;
+ unsigned char *temp = (unsigned char *) &raw_tar_header;
+ long i;
+ long next_header_offset = 0;
+ long uncompressed_count = 0;
+ size_t size;
+ mode_t mode;
+
+// signal(SIGCHLD, child_died);
+
+ while (fread((char *) &raw_tar_header, 1, 512, src_tar_file)==512) {
+ long sum = 0;
+ char *dir;
+
+ uncompressed_count += 512;
+
+ /* Check header has valid magic */
+ if (strncmp(raw_tar_header.magic, "ustar", 5) != 0) {
+ /* Put this pack after TODO (check child still alive) is done */
+// error_msg("Invalid tar magic");
+ break;
+ }
+
+ /* Do checksum on headers */
+ for (i = 0; i < 148 ; i++) {
+ sum += temp[i];
+ }
+ sum += ' ' * 8;
+ for (i = 156; i < 512 ; i++) {
+ sum += temp[i];
+ }
+ if (sum != strtol(raw_tar_header.chksum, NULL, 8)) {
+ error_msg("Invalid tar header checksum");
+ break;
+ }
+
+ /* convert to type'ed variables */
+ size = strtol(raw_tar_header.size, NULL, 8);
+ parse_mode(raw_tar_header.mode, &mode);
+
+ /* start of next header is at */
+ next_header_offset = uncompressed_count + size;
+ if (size % 512 != 0) {
+ next_header_offset += (512 - size % 512);
+ }
+
+ /*
+ * seek to start of control file, return length
+ *
+ if (dpkg_untar_function & dpkg_untar_seek_control) {
+ if ((raw_tar_header.typeflag == '0') || (raw_tar_header.typeflag == '\0')) {
+ char *tar_filename;
+
+ tar_filename = strrchr(raw_tar_header.name, '/');
+ if (tar_filename == NULL) {
+ tar_filename = strdup(raw_tar_header.name);
+ } else {
+ tar_filename++;
+ }
+
+ if (strcmp(tar_filename, "control") == 0) {
+ return(size);
+ }
+ }
+
+ }
+*/
+ /* extract files */
+ dir = xmalloc(strlen(raw_tar_header.name) + strlen(base_path) + 2);
+
+ sprintf(dir, "%s/%s", base_path, raw_tar_header.name);
+ create_path(dir, 0777);
+ switch (raw_tar_header.typeflag ) {
+ case '0':
+ case '\0':
+ /* If the name ends in a '/' then assume it is
+ * supposed to be a directory, and fall through
+ */
+ if (raw_tar_header.name[strlen(raw_tar_header.name)-1] != '/') {
+ if (untar_function & untar_extract) {
+ int out_count=0;
+ FILE *dst_file;
+
+ dst_file = wfopen(dir, "w");
+ if (copy_file_chunk(src_tar_file, dst_file, size) == FALSE) {
+ error_msg_and_die("Couldnt extract file");
+ }
+ uncompressed_count += out_count;
+ fclose(dst_file);
+ break;
+ }
+ }
+ case '5':
+ if (untar_function & untar_extract) {
+ if (create_path(dir, mode) != TRUE) {
+ free(dir);
+ perror_msg("%s: Cannot mkdir", raw_tar_header.name);
+ return(EXIT_FAILURE);
+ }
+ }
+ break;
+ case '1':
+ if (untar_function & untar_extract) {
+ if (link(raw_tar_header.linkname, raw_tar_header.name) < 0) {
+ free(dir);
+ perror_msg("%s: Cannot create hard link to '%s'", raw_tar_header.name, raw_tar_header.linkname);
+ return(EXIT_FAILURE);
+ }
+ }
+ break;
+ case '2':
+ if (untar_function & untar_extract) {
+ if (symlink(raw_tar_header.linkname, raw_tar_header.name) < 0) {
+ free(dir);
+ perror_msg("%s: Cannot create symlink to '%s'", raw_tar_header.name, raw_tar_header.linkname);
+ return(EXIT_FAILURE);
+ }
+ }
+ break;
+ case '3':
+ case '4':
+ case '6':
+// if (tarExtractSpecial( &header, extractFlag, tostdoutFlag)==FALSE)
+// errorFlag=TRUE;
+// break;
+ default:
+ error_msg("Unknown file type '%c' in tar file", raw_tar_header.typeflag);
+ free(dir);
+ return(EXIT_FAILURE);
+ }
+ free(dir);
+ }
+ /* skip to start of next header */
+ while(uncompressed_count < next_header_offset) {
+ char ch[2];
+ if (fread(ch, 1, 1, src_tar_file) != 1) {
+ error_msg("read error\n");
+ getchar();
+ } else {
+ uncompressed_count++;
+ }
+ }
+ /*
+ * TODO: Check that gunzip child hasnt finished
+ */
+ return(EXIT_SUCCESS);
+}