busybox/archival/libunarchive/get_header_cpio.c
Denis Vlasenko 3eb91c2e35 cpio: (allegedly) fix bug 0001095:
"cpio hardlink support and possible memory leak fix"
2006-11-21 00:55:46 +00:00

161 lines
4.4 KiB
C

/* vi: set sw=4 ts=4: */
/* Copyright 2002 Laurence Anderson
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
#include "libbb.h"
#include "unarchive.h"
typedef struct hardlinks_s {
char *name;
int inode;
struct hardlinks_s *next;
} hardlinks_t;
char get_header_cpio(archive_handle_t *archive_handle)
{
static hardlinks_t *saved_hardlinks = NULL;
static unsigned short pending_hardlinks = 0;
static int inode;
file_header_t *file_header = archive_handle->file_header;
char cpio_header[110];
int namesize;
char dummy[16];
int major, minor, nlink;
if (pending_hardlinks) { /* Deal with any pending hardlinks */
hardlinks_t *tmp, *oldtmp;
tmp = saved_hardlinks;
oldtmp = NULL;
file_header->link_name = file_header->name;
file_header->size = 0;
while (tmp) {
if (tmp->inode != inode) {
tmp = tmp->next;
continue;
}
file_header->name = tmp->name;
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_data(archive_handle);
archive_handle->action_header(archive_handle->file_header);
}
pending_hardlinks--;
oldtmp = tmp;
tmp = tmp->next;
free(oldtmp->name);
free(oldtmp);
if (oldtmp == saved_hardlinks)
saved_hardlinks = tmp;
}
file_header->name = file_header->link_name;
if (pending_hardlinks > 1) {
bb_error_msg("error resolving hardlink: archive made by GNU cpio 2.0-2.2?");
}
/* No more pending hardlinks, read next file entry */
pending_hardlinks = 0;
}
/* There can be padding before archive header */
data_align(archive_handle, 4);
if (archive_xread_all_eof(archive_handle, (unsigned char*)cpio_header, 110) == 0) {
return EXIT_FAILURE;
}
archive_handle->offset += 110;
if (strncmp(&cpio_header[0], "07070", 5) != 0
|| (cpio_header[5] != '1' && cpio_header[5] != '2')
) {
bb_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;
}
free(file_header->name);
file_header->name = xzalloc(namesize + 1);
/* Read in filename */
xread(archive_handle->src_fd, file_header->name, namesize);
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) {
/* Always round up */
printf("%d blocks\n", (int) (archive_handle->offset % 512 ?
archive_handle->offset / 512 + 1 :
archive_handle->offset / 512
));
if (saved_hardlinks) { /* Bummer - we still have unresolved hardlinks */
hardlinks_t *tmp = saved_hardlinks;
hardlinks_t *oldtmp = NULL;
while (tmp) {
bb_error_msg("%s not created: cannot resolve hardlink", tmp->name);
oldtmp = tmp;
tmp = tmp->next;
free(oldtmp->name);
free(oldtmp);
}
saved_hardlinks = NULL;
pending_hardlinks = 0;
}
return EXIT_FAILURE;
}
if (S_ISLNK(file_header->mode)) {
file_header->link_name = xzalloc(file_header->size + 1);
xread(archive_handle->src_fd, file_header->link_name, file_header->size);
archive_handle->offset += file_header->size;
file_header->size = 0; /* Stop possible seeks in future */
} else {
file_header->link_name = NULL;
}
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;
/* name current allocated, freed later */
new->name = file_header->name;
file_header->name = NULL;
saved_hardlinks = new;
return EXIT_SUCCESS; /* Skip this one */
}
/* Found the file with data in */
pending_hardlinks = nlink;
}
file_header->device = makedev(major, minor);
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_data(archive_handle);
archive_handle->action_header(archive_handle->file_header);
} else {
data_skip(archive_handle);
}
archive_handle->offset += file_header->size;
free(file_header->link_name);
return (EXIT_SUCCESS);
}