source: MondoRescue/branches/2.2.9/mindi-busybox/archival/rpm2cpio.c@ 2887

/* 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.
 */
#include "libbb.h"
#include "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 0
    /* This works, but doesn't report uncompress errors (they happen in child) */
    setup_unzip_on_fd(rpm_fd /*fail_if_not_detected: 1*/);
    if (bb_copyfd_eof(rpm_fd, STDOUT_FILENO) < 0)
        bb_error_msg_and_die("error unpacking");
#else
    /* BLOAT */
    {
        union {
            uint8_t b[4];
            uint16_t b16[2];
            uint32_t b32[1];
        } magic;
        IF_DESKTOP(long long) int FAST_FUNC (*unpack)(int src_fd, int dst_fd);

        xread(rpm_fd, magic.b16, sizeof(magic.b16[0]));
        if (magic.b16[0] == GZIP_MAGIC) {
            unpack = unpack_gz_stream;
        } else
        if (ENABLE_FEATURE_SEAMLESS_BZ2
         && magic.b16[0] == BZIP2_MAGIC
        ) {
            unpack = unpack_bz2_stream;
        } else
        if (ENABLE_FEATURE_SEAMLESS_XZ
         && magic.b16[0] == XZ_MAGIC1
        ) {
            xread(rpm_fd, magic.b32, sizeof(magic.b32[0]));
            if (magic.b32[0] != XZ_MAGIC2)
                goto no_magic;
            /* unpack_xz_stream wants fd at position 6, no need to seek */
            //xlseek(rpm_fd, -6, SEEK_CUR);
            unpack = unpack_xz_stream;
        } else {
 no_magic:
            bb_error_msg_and_die("no gzip"
                    IF_FEATURE_SEAMLESS_BZ2("/bzip2")
                    IF_FEATURE_SEAMLESS_XZ("/xz")
                    " magic");
        }
        if (unpack(rpm_fd, STDOUT_FILENO) < 0)
            bb_error_msg_and_die("error unpacking");
    }
#endif

    if (ENABLE_FEATURE_CLEAN_UP) {
        close(rpm_fd);
    }

    return 0;
}