busybox/archival/rpm2cpio.c
Denys Vlasenko 9be166b5dd rpm: code shrink
function                                             old     new   delta
rpm_getstr0                                            -       7      +7
rpm_getstr                                           112     110      -2
rpm_getint                                           120     118      -2
bsearch_rpmtag                                        15      13      -2
shell_builtin_read                                  1334    1320     -14
rpm_main                                            1548    1474     -74
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/5 up/down: 7/-94)             Total: -87 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2017-08-09 18:20:01 +02:00

100 lines
2.6 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini rpm2cpio implementation for busybox
*
* Copyright (C) 2001 by Laurence Anderson
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//config:config RPM2CPIO
//config: bool "rpm2cpio (20 kb)"
//config: default y
//config: help
//config: Converts a RPM file into a CPIO archive.
//applet:IF_RPM2CPIO(APPLET(rpm2cpio, BB_DIR_USR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_RPM2CPIO) += rpm2cpio.o
//usage:#define rpm2cpio_trivial_usage
//usage: "package.rpm"
//usage:#define rpm2cpio_full_usage "\n\n"
//usage: "Output a cpio archive of the rpm file"
#include "libbb.h"
#include "bb_archive.h"
#include "rpm.h"
enum { rpm_fd = STDIN_FILENO };
static unsigned skip_header(void)
{
struct rpm_header header;
unsigned len;
xread(rpm_fd, &header, sizeof(header));
// if (strncmp((char *) &header.magic, RPM_HEADER_MAGIC_STR, 3) != 0) {
// bb_error_msg_and_die("invalid RPM header magic");
// }
// if (header.version != 1) {
// bb_error_msg_and_die("unsupported RPM header version");
// }
if (header.magic_and_ver != htonl(RPM_HEADER_MAGICnVER)) {
bb_error_msg_and_die("invalid RPM header magic or unsupported version");
// ": %x != %x", header.magic_and_ver, htonl(RPM_HEADER_MAGICnVER));
}
/* Seek past index entries, and past store */
len = 16 * ntohl(header.entries) + ntohl(header.size);
seek_by_jump(rpm_fd, len);
return sizeof(header) + len;
}
/* No getopt required */
int rpm2cpio_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int rpm2cpio_main(int argc UNUSED_PARAM, char **argv)
{
struct rpm_lead lead;
unsigned pos;
if (argv[1]) {
xmove_fd(xopen(argv[1], O_RDONLY), rpm_fd);
}
xread(rpm_fd, &lead, sizeof(lead));
/* Just check the magic, the rest is irrelevant */
if (lead.magic != htonl(RPM_LEAD_MAGIC)) {
bb_error_msg_and_die("invalid RPM magic");
}
/* Skip the signature header, align to 8 bytes */
pos = skip_header();
seek_by_jump(rpm_fd, (-(int)pos) & 7);
/* Skip the main header */
skip_header();
//if (SEAMLESS_COMPRESSION) - we do this at the end instead.
// /* We need to know whether child (gzip/bzip/etc) exits abnormally */
// signal(SIGCHLD, check_errors_in_children);
//TODO: look for rpm tag RPMTAG_PAYLOADCOMPRESSOR (dec 1125, hex 0x465),
// if the value is "lzma", set up decompressor without detection
// (lzma can't be detected).
setup_unzip_on_fd(rpm_fd, /*fail_if_not_compressed:*/ 1);
if (bb_copyfd_eof(rpm_fd, STDOUT_FILENO) < 0)
bb_error_msg_and_die("error unpacking");
if (ENABLE_FEATURE_CLEAN_UP) {
close(rpm_fd);
}
if (SEAMLESS_COMPRESSION) {
check_errors_in_children(0);
return bb_got_signal;
}
return EXIT_SUCCESS;
}