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