src/partition/makefs.c

   1 /***
   2   SPDX-License-Identifier: LGPL-2.1+
   3
   4   Copyright © 2017 Zbigniew Jędrzejewski-Szmek
   5 ***/
   6
   7 #include <fcntl.h>
   8 #include <signal.h>
   9 #include <sys/prctl.h>
  10 #include <sys/stat.h>
  11 #include <sys/types.h>
  12 #include <unistd.h>
  13
  14 #include "alloc-util.h"
  15 #include "dissect-image.h"
  16 #include "process-util.h"
  17 #include "signal-util.h"
  18 #include "string-util.h"
  19
  20 static int makefs(const char *type, const char *device) {
  21         const char *mkfs;
  22         pid_t pid;
  23         int r;
  24
  25         if (streq(type, "swap"))
  26                 mkfs = "/sbin/mkswap";
  27         else
  28                 mkfs = strjoina("/sbin/mkfs.", type);
  29         if (access(mkfs, X_OK) != 0)
  30                 return log_error_errno(errno, "%s is not executable: %m", mkfs);
  31
  32         r = safe_fork("(fsck)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_LOG, &pid);
  33         if (r < 0)
  34                 return r;
  35         if (r == 0) {
  36                 const char *cmdline[3] = { mkfs, device, NULL };
  37
  38                 /* Child */
  39
  40                 execv(cmdline[0], (char**) cmdline);
  41                 _exit(EXIT_FAILURE);
  42         }
  43
  44         return wait_for_terminate_and_check(mkfs, pid, WAIT_LOG);
  45 }
  46
  47 int main(int argc, char *argv[]) {
  48         const char *device, *type;
  49         _cleanup_free_ char *detected = NULL;
  50         struct stat st;
  51         int r;
  52
  53         log_set_target(LOG_TARGET_AUTO);
  54         log_parse_environment();
  55         log_open();
  56
  57         if (argc != 3) {
  58                 log_error("This program expects two arguments.");
  59                 return EXIT_FAILURE;
  60         }
  61
  62         type = argv[1];
  63         device = argv[2];
  64
  65         if (stat(device, &st) < 0) {
  66                 r = log_error_errno(errno, "Failed to stat \"%s\": %m", device);
  67                 goto finish;
  68         }
  69
  70         if (!S_ISBLK(st.st_mode))
  71                 log_info("%s is not a block device.", device);
  72
  73         r = probe_filesystem(device, &detected);
  74         if (r < 0) {
  75                 log_warning_errno(r,
  76                                   r == -EUCLEAN ?
  77                                   "Cannot reliably determine probe \"%s\", refusing to proceed." :
  78                                   "Failed to probe \"%s\": %m",
  79                                   device);
  80                 goto finish;
  81         }
  82
  83         if (detected) {
  84                 log_info("%s is not empty (type %s), exiting", device, detected);
  85                 goto finish;
  86         }
  87
  88         r = makefs(type, device);
  89
  90 finish:
  91         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
  92 }