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/* vi: set sw=4 ts=4: */
/*
* Copyright 2002 Laurence Anderson
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
#include "libbb.h"
#include "bb_archive.h"
typedef struct hardlinks_t {
struct hardlinks_t *next;
int inode; /* TODO: must match maj/min too! */
int mode ;
int mtime; /* These three are useful only in corner case */
int uid ; /* of hardlinks with zero size body */
int gid ;
char name[1];
} hardlinks_t;
char FAST_FUNC get_header_cpio(archive_handle_t *archive_handle)
{
file_header_t *file_header = archive_handle->file_header;
char cpio_header[110];
int namesize;
int major, minor, nlink, mode, inode;
unsigned size, uid, gid, mtime;
/* There can be padding before archive header */
data_align(archive_handle, 4);
size = full_read(archive_handle->src_fd, cpio_header, 110);
if (size == 0) {
goto create_hardlinks;
}
if (size != 110) {
bb_error_msg_and_die("short read");
}
archive_handle->offset += 110;
if (!is_prefixed_with(&cpio_header[0], "07070")
|| (cpio_header[5] != '1' && cpio_header[5] != '2')
) {
bb_error_msg_and_die("unsupported cpio format, use newc or crc");
}
if (sscanf(cpio_header + 6,
"%8x" "%8x" "%8x" "%8x"
"%8x" "%8x" "%8x" /*maj,min:*/ "%*16c"
/*rmaj,rmin:*/"%8x" "%8x" "%8x" /*chksum: "%*8c"*/,
&inode, &mode, &uid, &gid,
&nlink, &mtime, &size,
&major, &minor, &namesize) != 10)
bb_error_msg_and_die("damaged cpio file");
file_header->mode = mode;
/* "cpio -R USER:GRP" support: */
if (archive_handle->cpio__owner.uid != (uid_t)-1L)
uid = archive_handle->cpio__owner.uid;
if (archive_handle->cpio__owner.gid != (gid_t)-1L)
gid = archive_handle->cpio__owner.gid;
file_header->uid = uid;
file_header->gid = gid;
file_header->mtime = mtime;
file_header->size = size;
namesize &= 0x1fff; /* paranoia: limit names to 8k chars */
file_header->name = xzalloc(namesize + 1);
/* Read in filename */
xread(archive_handle->src_fd, file_header->name, namesize);
if (file_header->name[0] == '/') {
/* Testcase: echo /etc/hosts | cpio -pvd /tmp
* Without this code, it tries to unpack /etc/hosts
* into "/etc/hosts", not "etc/hosts".
*/
char *p = file_header->name;
do p++; while (*p == '/');
overlapping_strcpy(file_header->name, p);
}
archive_handle->offset += namesize;
/* Update offset amount and skip padding before file contents */
data_align(archive_handle, 4);
if (strcmp(file_header->name, cpio_TRAILER) == 0) {
/* Always round up. ">> 9" divides by 512 */
archive_handle->cpio__blocks = (uoff_t)(archive_handle->offset + 511) >> 9;
goto create_hardlinks;
}
file_header->link_target = NULL;
if (S_ISLNK(file_header->mode)) {
file_header->size &= 0x1fff; /* paranoia: limit names to 8k chars */
file_header->link_target = xzalloc(file_header->size + 1);
xread(archive_handle->src_fd, file_header->link_target, file_header->size);
archive_handle->offset += file_header->size;
file_header->size = 0; /* Stop possible seeks in future */
}
// TODO: data_extract_all can't deal with hardlinks to non-files...
// when fixed, change S_ISREG to !S_ISDIR here
if (nlink > 1 && S_ISREG(file_header->mode)) {
hardlinks_t *new = xmalloc(sizeof(*new) + namesize);
new->inode = inode;
new->mode = mode ;
new->mtime = mtime;
new->uid = uid ;
new->gid = gid ;
strcpy(new->name, file_header->name);
/* Put file on a linked list for later */
if (size == 0) {
new->next = archive_handle->cpio__hardlinks_to_create;
archive_handle->cpio__hardlinks_to_create = new;
return EXIT_SUCCESS; /* Skip this one */
/* TODO: this breaks cpio -t (it does not show hardlinks) */
}
new->next = archive_handle->cpio__created_hardlinks;
archive_handle->cpio__created_hardlinks = new;
}
file_header->device = makedev(major, minor);
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS) {
archive_handle->action_data(archive_handle);
//TODO: run "echo /etc/hosts | cpio -pv /tmp" twice. On 2nd run:
//cpio: etc/hosts not created: newer or same age file exists
//etc/hosts <-- should NOT show it
//2 blocks <-- should say "0 blocks"
archive_handle->action_header(file_header);
} else {
data_skip(archive_handle);
}
archive_handle->offset += file_header->size;
free(file_header->link_target);
free(file_header->name);
file_header->link_target = NULL;
file_header->name = NULL;
return EXIT_SUCCESS;
create_hardlinks:
free(file_header->link_target);
free(file_header->name);
while (archive_handle->cpio__hardlinks_to_create) {
hardlinks_t *cur;
hardlinks_t *make_me = archive_handle->cpio__hardlinks_to_create;
archive_handle->cpio__hardlinks_to_create = make_me->next;
memset(file_header, 0, sizeof(*file_header));
file_header->mtime = make_me->mtime;
file_header->name = make_me->name;
file_header->mode = make_me->mode;
file_header->uid = make_me->uid;
file_header->gid = make_me->gid;
/*file_header->size = 0;*/
/*file_header->link_target = NULL;*/
/* Try to find a file we are hardlinked to */
cur = archive_handle->cpio__created_hardlinks;
while (cur) {
/* TODO: must match maj/min too! */
if (cur->inode == make_me->inode) {
file_header->link_target = cur->name;
/* link_target != NULL, size = 0: "I am a hardlink" */
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS)
archive_handle->action_data(archive_handle);
free(make_me);
goto next_link;
}
cur = cur->next;
}
/* Oops... no file with such inode was created... do it now
* (happens when hardlinked files are empty (zero length)) */
if (archive_handle->filter(archive_handle) == EXIT_SUCCESS)
archive_handle->action_data(archive_handle);
/* Move to the list of created hardlinked files */
make_me->next = archive_handle->cpio__created_hardlinks;
archive_handle->cpio__created_hardlinks = make_me;
next_link: ;
}
while (archive_handle->cpio__created_hardlinks) {
hardlinks_t *p = archive_handle->cpio__created_hardlinks;
archive_handle->cpio__created_hardlinks = p->next;
free(p);
}
return EXIT_FAILURE; /* "No more files to process" */
}
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