src/shared/reboot-util.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <unistd.h>
   5
   6 #include "alloc-util.h"
   7 #include "fileio.h"
   8 #include "log.h"
   9 #include "raw-reboot.h"
  10 #include "reboot-util.h"
  11 #include "string-util.h"
  12 #include "umask-util.h"
  13 #include "virt.h"
  14
  15 int update_reboot_parameter_and_warn(const char *parameter, bool keep) {
  16         int r;
  17
  18         if (isempty(parameter)) {
  19                 if (keep)
  20                         return 0;
  21
  22                 if (unlink("/run/systemd/reboot-param") < 0) {
  23                         if (errno == ENOENT)
  24                                 return 0;
  25
  26                         return log_warning_errno(errno, "Failed to unlink reboot parameter file: %m");
  27                 }
  28
  29                 return 0;
  30         }
  31
  32         RUN_WITH_UMASK(0022) {
  33                 r = write_string_file("/run/systemd/reboot-param", parameter,
  34                                       WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
  35                 if (r < 0)
  36                         return log_warning_errno(r, "Failed to write reboot parameter file: %m");
  37         }
  38
  39         return 0;
  40 }
  41
  42 int reboot_with_parameter(RebootFlags flags) {
  43         int r;
  44
  45         /* Reboots the system with a parameter that is read from /run/systemd/reboot-param. Returns 0 if REBOOT_DRY_RUN
  46          * was set and the actual reboot operation was hence skipped. If REBOOT_FALLBACK is set and the reboot with
  47          * parameter doesn't work out a fallback to classic reboot() is attempted. If REBOOT_FALLBACK is not set, 0 is
  48          * returned instead, which should be considered indication for the caller to fall back to reboot() on its own,
  49          * or somehow else deal with this. If REBOOT_LOG is specified will log about what it is going to do, as well as
  50          * all errors. */
  51
  52         if (detect_container() == 0) {
  53                 _cleanup_free_ char *parameter = NULL;
  54
  55                 r = read_one_line_file("/run/systemd/reboot-param", &parameter);
  56                 if (r < 0 && r != -ENOENT)
  57                         log_full_errno(flags & REBOOT_LOG ? LOG_WARNING : LOG_DEBUG, r,
  58                                        "Failed to read reboot parameter file, ignoring: %m");
  59
  60                 if (!isempty(parameter)) {
  61
  62                         log_full(flags & REBOOT_LOG ? LOG_INFO : LOG_DEBUG,
  63                                  "Rebooting with argument '%s'.", parameter);
  64
  65                         if (flags & REBOOT_DRY_RUN)
  66                                 return 0;
  67
  68                         (void) raw_reboot(LINUX_REBOOT_CMD_RESTART2, parameter);
  69
  70                         log_full_errno(flags & REBOOT_LOG ? LOG_WARNING : LOG_DEBUG, errno,
  71                                        "Failed to reboot with parameter, retrying without: %m");
  72                 }
  73         }
  74
  75         if (!(flags & REBOOT_FALLBACK))
  76                 return 0;
  77
  78         log_full(flags & REBOOT_LOG ? LOG_INFO : LOG_DEBUG, "Rebooting.");
  79
  80         if (flags & REBOOT_DRY_RUN)
  81                 return 0;
  82
  83         (void) reboot(RB_AUTOBOOT);
  84
  85         return log_full_errno(flags & REBOOT_LOG ? LOG_ERR : LOG_DEBUG, errno, "Failed to reboot: %m");
  86 }