busybox/archival/libunarchive/get_header_cpio.c

190 lines
5.8 KiB
C

/*
* 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 <unistd.h>
#include "unarchive.h"
#include "libbb.h"
typedef struct hardlinks_s {
file_header_t *entry;
int inode;
struct hardlinks_s *next;
} hardlinks_t;
extern char get_header_cpio(archive_handle_t *archive_handle)
{
static hardlinks_t *saved_hardlinks = NULL;
static unsigned short pending_hardlinks = 0;
file_header_t *file_header = archive_handle->file_header;
char cpio_header[110];
int namesize;
char dummy[16];
int major, minor, nlink, inode;
char extract_flag;
if (pending_hardlinks) { /* Deal with any pending hardlinks */
hardlinks_t *tmp;
hardlinks_t *oldtmp;
tmp = saved_hardlinks;
oldtmp = NULL;
while (tmp) {
error_msg_and_die("need to fix this\n");
if (tmp->entry->link_name) { /* Found a hardlink ready to be extracted */
file_header = tmp->entry;
if (oldtmp) {
oldtmp->next = tmp->next; /* Remove item from linked list */
} else {
saved_hardlinks = tmp->next;
}
free(tmp);
continue;
}
oldtmp = tmp;
tmp = tmp->next;
}
pending_hardlinks = 0; /* No more pending hardlinks, read next file entry */
}
/* There can be padding before archive header */
data_align(archive_handle, 4);
if (archive_xread_all_eof(archive_handle, cpio_header, 110) == 0) {
return(EXIT_FAILURE);
}
archive_handle->offset += 110;
if (strncmp(&cpio_header[0], "07070", 5) != 0) {
printf("cpio header is %x-%x-%x-%x-%x\n",
cpio_header[0],
cpio_header[1],
cpio_header[2],
cpio_header[3],
cpio_header[4]);
error_msg_and_die("Unsupported cpio format");
}
if ((cpio_header[5] != '1') && (cpio_header[5] != '2')) {
error_msg_and_die("Unsupported cpio format, use newc or crc");
}
{
unsigned long tmpsize;
sscanf(cpio_header, "%6c%8x%8x%8x%8x%8x%8lx%8lx%16c%8x%8x%8x%8c",
dummy, &inode, (unsigned int*)&file_header->mode,
(unsigned int*)&file_header->uid, (unsigned int*)&file_header->gid,
&nlink, &file_header->mtime, &tmpsize,
dummy, &major, &minor, &namesize, dummy);
file_header->size = tmpsize;
}
file_header->name = (char *) xmalloc(namesize + 1);
archive_xread_all(archive_handle, file_header->name, namesize); /* Read in filename */
file_header->name[namesize] = '\0';
archive_handle->offset += namesize;
/* Update offset amount and skip padding before file contents */
data_align(archive_handle, 4);
if (strcmp(file_header->name, "TRAILER!!!") == 0) {
printf("%d blocks\n", (int) (archive_handle->offset % 512 ? (archive_handle->offset / 512) + 1 : archive_handle->offset / 512)); /* Always round up */
if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
hardlinks_t *tmp = saved_hardlinks;
hardlinks_t *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(EXIT_FAILURE);
}
if (S_ISLNK(file_header->mode)) {
file_header->link_name = (char *) xmalloc(file_header->size + 1);
archive_xread_all(archive_handle, file_header->link_name, file_header->size);
file_header->link_name[file_header->size] = '\0';
archive_handle->offset += file_header->size;
file_header->size = 0; /* Stop possible seeks in future */
}
if (nlink > 1 && !S_ISDIR(file_header->mode)) {
if (file_header->size == 0) { /* Put file on a linked list for later */
hardlinks_t *new = xmalloc(sizeof(hardlinks_t));
new->next = saved_hardlinks;
new->inode = inode;
new->entry = file_header;
saved_hardlinks = new;
return(EXIT_SUCCESS); // Skip this one
} else { /* Found the file with data in */
hardlinks_t *tmp = saved_hardlinks;
pending_hardlinks = 1;
while (tmp) {
if (tmp->inode == inode) {
tmp->entry->link_name = xstrdup(file_header->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?");
}
}
}
file_header->device = (major << 8) | minor;
extract_flag = FALSE;
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
struct stat statbuf;
extract_flag = TRUE;
/* Check if the file already exists */
if (lstat (file_header->name, &statbuf) == 0) {
if ((archive_handle->flags & ARCHIVE_EXTRACT_UNCONDITIONAL) || (statbuf.st_mtime < file_header->mtime)) {
/* Remove file if flag set or its older than the file to be extracted */
if (unlink(file_header->name) == -1) {
perror_msg_and_die("Couldnt remove old file");
}
} else {
if (! archive_handle->flags & ARCHIVE_EXTRACT_QUIET) {
error_msg("%s not created: newer or same age file exists", file_header->name);
}
extract_flag = FALSE;
}
}
archive_handle->action_header(file_header);
}
archive_handle->action_header(file_header);
if (extract_flag) {
archive_handle->action_data(archive_handle);
} else {
data_skip(archive_handle);
}
archive_handle->offset += file_header->size;
return (EXIT_SUCCESS);
}