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Diffstat (limited to 'archival/libunarchive/get_header_cpio.c')
-rw-r--r--archival/libunarchive/get_header_cpio.c136
1 files changed, 136 insertions, 0 deletions
diff --git a/archival/libunarchive/get_header_cpio.c b/archival/libunarchive/get_header_cpio.c
new file mode 100644
index 0000000..a2136e4
--- /dev/null
+++ b/archival/libunarchive/get_header_cpio.c
@@ -0,0 +1,136 @@
+/*
+ * 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.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "unarchive.h"
+#include "libbb.h"
+
+struct hardlinks {
+ file_header_t *entry;
+ int inode;
+ struct hardlinks *next;
+};
+
+file_header_t *get_header_cpio(FILE *src_stream)
+{
+ file_header_t *cpio_entry = NULL;
+ char cpio_header[110];
+ int namesize;
+ char dummy[16];
+ int major, minor, nlink, inode;
+ static struct hardlinks *saved_hardlinks = NULL;
+ static int pending_hardlinks = 0;
+
+ if (pending_hardlinks) { /* Deal with any pending hardlinks */
+ struct hardlinks *tmp = saved_hardlinks, *oldtmp = NULL;
+ while (tmp) {
+ if (tmp->entry->link_name) { /* Found a hardlink ready to be extracted */
+ cpio_entry = tmp->entry;
+ if (oldtmp) oldtmp->next = tmp->next; /* Remove item from linked list */
+ else saved_hardlinks = tmp->next;
+ free(tmp);
+ return (cpio_entry);
+ }
+ oldtmp = tmp;
+ tmp = tmp->next;
+ }
+ pending_hardlinks = 0; /* No more pending hardlinks, read next file entry */
+ }
+
+ /* There can be padding before archive header */
+ seek_sub_file(src_stream, (4 - (archive_offset % 4)) % 4);
+ if (fread(cpio_header, 1, 110, src_stream) == 110) {
+ archive_offset += 110;
+ if (strncmp(cpio_header, "07070", 5) != 0) {
+ error_msg("Unsupported format or invalid magic");
+ return(NULL);
+ }
+ switch (cpio_header[5]) {
+ case '2': /* "crc" header format */
+ /* Doesnt do the crc check yet */
+ case '1': /* "newc" header format */
+ cpio_entry = (file_header_t *) xcalloc(1, sizeof(file_header_t));
+ sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c",
+ dummy, &inode, (unsigned int*)&cpio_entry->mode,
+ (unsigned int*)&cpio_entry->uid, (unsigned int*)&cpio_entry->gid,
+ &nlink, &cpio_entry->mtime, &cpio_entry->size,
+ dummy, &major, &minor, &namesize, dummy);
+
+ cpio_entry->name = (char *) xcalloc(1, namesize);
+ fread(cpio_entry->name, 1, namesize, src_stream); /* Read in filename */
+ archive_offset += namesize;
+ /* Skip padding before file contents */
+ seek_sub_file(src_stream, (4 - (archive_offset % 4)) % 4);
+ if (strcmp(cpio_entry->name, "TRAILER!!!") == 0) {
+ printf("%d blocks\n", (int) (archive_offset % 512 ? (archive_offset / 512) + 1 : archive_offset / 512)); /* Always round up */
+ if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
+ struct hardlinks *tmp = saved_hardlinks, *oldtmp = NULL;
+ while (tmp) {
+ error_msg("%s not created: cannot resolve hardlink", tmp->entry->name);
+ oldtmp = tmp;
+ tmp = tmp->next;
+ free (oldtmp->entry->name);
+ free (oldtmp->entry);
+ free (oldtmp);
+ }
+ saved_hardlinks = NULL;
+ pending_hardlinks = 0;
+ }
+ return(NULL);
+ }
+
+ if (S_ISLNK(cpio_entry->mode)) {
+ cpio_entry->link_name = (char *) xcalloc(1, cpio_entry->size + 1);
+ fread(cpio_entry->link_name, 1, cpio_entry->size, src_stream);
+ archive_offset += cpio_entry->size;
+ cpio_entry->size = 0; /* Stop possiable seeks in future */
+ }
+ if (nlink > 1 && !S_ISDIR(cpio_entry->mode)) {
+ if (cpio_entry->size == 0) { /* Put file on a linked list for later */
+ struct hardlinks *new = xmalloc(sizeof(struct hardlinks));
+ new->next = saved_hardlinks;
+ new->inode = inode;
+ new->entry = cpio_entry;
+ saved_hardlinks = new;
+ return(get_header_cpio(src_stream)); /* Recurse to next file */
+ } else { /* Found the file with data in */
+ struct hardlinks *tmp = saved_hardlinks;
+ pending_hardlinks = 1;
+ while (tmp) {
+ if (tmp->inode == inode) {
+ tmp->entry->link_name = xstrdup(cpio_entry->name);
+ nlink--;
+ }
+ tmp = tmp->next;
+ }
+ if (nlink > 1) error_msg("error resolving hardlink: did you create the archive with GNU cpio 2.0-2.2?");
+ }
+ }
+ cpio_entry->device = (major << 8) | minor;
+ break;
+ default:
+ error_msg("Unsupported format");
+ return(NULL);
+ }
+ if (ferror(src_stream) || feof(src_stream)) {
+ perror_msg("Stream error");
+ return(NULL);
+ }
+ }
+ return(cpio_entry);
+} \ No newline at end of file