src/partition/makefs.c

   1 /***
   2   SPDX-License-Identifier: LGPL-2.1+
   3
   4   This file is part of systemd.
   5
   6   Copyright 2017 Zbigniew Jędrzejewski-Szmek
   7 ***/
   8
   9 #include <fcntl.h>
  10 #include <signal.h>
  11 #include <sys/prctl.h>
  12 #include <sys/stat.h>
  13 #include <sys/types.h>
  14 #include <unistd.h>
  15
  16 #include "alloc-util.h"
  17 #include "dissect-image.h"
  18 #include "process-util.h"
  19 #include "signal-util.h"
  20 #include "string-util.h"
  21
  22 static int makefs(const char *type, const char *device) {
  23         const char *mkfs;
  24         pid_t pid;
  25         int r;
  26
  27         if (streq(type, "swap"))
  28                 mkfs = "/sbin/mkswap";
  29         else
  30                 mkfs = strjoina("/sbin/mkfs.", type);
  31         if (access(mkfs, X_OK) != 0)
  32                 return log_error_errno(errno, "%s is not executable: %m", mkfs);
  33
  34         r = safe_fork("(fsck)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_LOG, &pid);
  35         if (r < 0)
  36                 return r;
  37         if (r == 0) {
  38                 const char *cmdline[3] = { mkfs, device, NULL };
  39
  40                 /* Child */
  41
  42                 execv(cmdline[0], (char**) cmdline);
  43                 _exit(EXIT_FAILURE);
  44         }
  45
  46         return wait_for_terminate_and_check(mkfs, pid, WAIT_LOG);
  47 }
  48
  49 int main(int argc, char *argv[]) {
  50         const char *device, *type;
  51         _cleanup_free_ char *detected = NULL;
  52         struct stat st;
  53         int r;
  54
  55         log_set_target(LOG_TARGET_AUTO);
  56         log_parse_environment();
  57         log_open();
  58
  59         if (argc != 3) {
  60                 log_error("This program expects two arguments.");
  61                 return EXIT_FAILURE;
  62         }
  63
  64         type = argv[1];
  65         device = argv[2];
  66
  67         if (stat(device, &st) < 0) {
  68                 r = log_error_errno(errno, "Failed to stat \"%s\": %m", device);
  69                 goto finish;
  70         }
  71
  72         if (!S_ISBLK(st.st_mode))
  73                 log_info("%s is not a block device.", device);
  74
  75         r = probe_filesystem(device, &detected);
  76         if (r < 0) {
  77                 log_warning_errno(r,
  78                                   r == -EUCLEAN ?
  79                                   "Cannot reliably determine probe \"%s\", refusing to proceed." :
  80                                   "Failed to probe \"%s\": %m",
  81                                   device);
  82                 goto finish;
  83         }
  84
  85         if (detected) {
  86                 log_info("%s is not empty (type %s), exiting", device, detected);
  87                 goto finish;
  88         }
  89
  90         r = makefs(type, device);
  91
  92 finish:
  93         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
  94 }