archival/rpm2cpio.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini rpm2cpio implementation for busybox
   4  *
   5  * Copyright (C) 2001 by Laurence Anderson
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 //usage:#define rpm2cpio_trivial_usage
  11 //usage:       "package.rpm"
  12 //usage:#define rpm2cpio_full_usage "\n\n"
  13 //usage:       "Output a cpio archive of the rpm file"
  14
  15 #include "libbb.h"
  16 #include "bb_archive.h"
  17 #include "rpm.h"
  18
  19 enum { rpm_fd = STDIN_FILENO };
  20
  21 static unsigned skip_header(void)
  22 {
  23         struct rpm_header header;
  24         unsigned len;
  25
  26         xread(rpm_fd, &header, sizeof(header));
  27 //      if (strncmp((char *) &header.magic, RPM_HEADER_MAGIC_STR, 3) != 0) {
  28 //              bb_error_msg_and_die("invalid RPM header magic");
  29 //      }
  30 //      if (header.version != 1) {
  31 //              bb_error_msg_and_die("unsupported RPM header version");
  32 //      }
  33         if (header.magic_and_ver != htonl(RPM_HEADER_MAGICnVER)) {
  34                 bb_error_msg_and_die("invalid RPM header magic or unsupported version");
  35                 // ": %x != %x", header.magic_and_ver, htonl(RPM_HEADER_MAGICnVER));
  36         }
  37
  38         /* Seek past index entries, and past store */
  39         len = 16 * ntohl(header.entries) + ntohl(header.size);
  40         seek_by_jump(rpm_fd, len);
  41
  42         return sizeof(header) + len;
  43 }
  44
  45 #if SEAMLESS_COMPRESSION
  46 static void handle_SIGCHLD(int signo UNUSED_PARAM)
  47 {
  48         int status;
  49
  50         /* Wait for any child without blocking */
  51         for (;;) {
  52                 if (wait_any_nohang(&status) < 0)
  53                         /* wait failed?! I'm confused... */
  54                         return;
  55                 if (WIFEXITED(status) && WEXITSTATUS(status) == 0)
  56                         /* this child exited with 0 */
  57                         continue;
  58                 /* Cannot happen?
  59                 if (!WIFSIGNALED(status) && !WIFEXITED(status)) ???; */
  60                 bb_got_signal = 1;
  61         }
  62 }
  63 #endif
  64
  65 /* No getopt required */
  66 int rpm2cpio_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  67 int rpm2cpio_main(int argc UNUSED_PARAM, char **argv)
  68 {
  69         struct rpm_lead lead;
  70         unsigned pos;
  71
  72         if (argv[1]) {
  73                 xmove_fd(xopen(argv[1], O_RDONLY), rpm_fd);
  74         }
  75         xread(rpm_fd, &lead, sizeof(lead));
  76
  77         /* Just check the magic, the rest is irrelevant */
  78         if (lead.magic != htonl(RPM_LEAD_MAGIC)) {
  79                 bb_error_msg_and_die("invalid RPM magic");
  80         }
  81
  82         /* Skip the signature header, align to 8 bytes */
  83         pos = skip_header();
  84         seek_by_jump(rpm_fd, (-(int)pos) & 7);
  85
  86         /* Skip the main header */
  87         skip_header();
  88
  89 #if SEAMLESS_COMPRESSION
  90         /* We need to know whether child (gzip/bzip/etc) exits abnormally */
  91         signal(SIGCHLD, handle_SIGCHLD);
  92 #endif
  93
  94         /* This works, but doesn't report uncompress errors (they happen in child) */
  95         setup_unzip_on_fd(rpm_fd, /*fail_if_not_detected:*/ 1);
  96         if (bb_copyfd_eof(rpm_fd, STDOUT_FILENO) < 0)
  97                 bb_error_msg_and_die("error unpacking");
  98
  99         if (ENABLE_FEATURE_CLEAN_UP) {
 100                 close(rpm_fd);
 101         }
 102
 103 #if SEAMLESS_COMPRESSION
 104         return bb_got_signal;
 105 #else
 106         return EXIT_SUCCESS;
 107 #endif
 108 }