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 "proc-cmdline.h"
  10 #include "raw-reboot.h"
  11 #include "reboot-util.h"
  12 #include "string-util.h"
  13 #include "umask-util.h"
  14 #include "virt.h"
  15
  16 int update_reboot_parameter_and_warn(const char *parameter, bool keep) {
  17         int r;
  18
  19         if (isempty(parameter)) {
  20                 if (keep)
  21                         return 0;
  22
  23                 if (unlink("/run/systemd/reboot-param") < 0) {
  24                         if (errno == ENOENT)
  25                                 return 0;
  26
  27                         return log_warning_errno(errno, "Failed to unlink reboot parameter file: %m");
  28                 }
  29
  30                 return 0;
  31         }
  32
  33         RUN_WITH_UMASK(0022) {
  34                 r = write_string_file("/run/systemd/reboot-param", parameter,
  35                                       WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_ATOMIC);
  36                 if (r < 0)
  37                         return log_warning_errno(r, "Failed to write reboot parameter file: %m");
  38         }
  39
  40         return 0;
  41 }
  42
  43 int read_reboot_parameter(char **parameter) {
  44         int r;
  45
  46         assert(parameter);
  47
  48         r = read_one_line_file("/run/systemd/reboot-param", parameter);
  49         if (r < 0 && r != -ENOENT)
  50                 return log_debug_errno(r, "Failed to read /run/systemd/reboot-param: %m");
  51
  52         return 0;
  53 }
  54
  55 int reboot_with_parameter(RebootFlags flags) {
  56         int r;
  57
  58         /* Reboots the system with a parameter that is read from /run/systemd/reboot-param. Returns 0 if
  59          * REBOOT_DRY_RUN was set and the actual reboot operation was hence skipped. If REBOOT_FALLBACK is
  60          * set and the reboot with parameter doesn't work out a fallback to classic reboot() is attempted. If
  61          * REBOOT_FALLBACK is not set, 0 is returned instead, which should be considered indication for the
  62          * caller to fall back to reboot() on its own, or somehow else deal with this. If REBOOT_LOG is
  63          * specified will log about what it is going to do, as well as all errors. */
  64
  65         if (detect_container() == 0) {
  66                 _cleanup_free_ char *parameter = NULL;
  67
  68                 r = read_one_line_file("/run/systemd/reboot-param", &parameter);
  69                 if (r < 0 && r != -ENOENT)
  70                         log_full_errno(flags & REBOOT_LOG ? LOG_WARNING : LOG_DEBUG, r,
  71                                        "Failed to read reboot parameter file, ignoring: %m");
  72
  73                 if (!isempty(parameter)) {
  74                         log_full(flags & REBOOT_LOG ? LOG_INFO : LOG_DEBUG,
  75                                  "Rebooting with argument '%s'.", parameter);
  76
  77                         if (flags & REBOOT_DRY_RUN)
  78                                 return 0;
  79
  80                         (void) raw_reboot(LINUX_REBOOT_CMD_RESTART2, parameter);
  81
  82                         log_full_errno(flags & REBOOT_LOG ? LOG_WARNING : LOG_DEBUG, errno,
  83                                        "Failed to reboot with parameter, retrying without: %m");
  84                 }
  85         }
  86
  87         if (!(flags & REBOOT_FALLBACK))
  88                 return 0;
  89
  90         log_full(flags & REBOOT_LOG ? LOG_INFO : LOG_DEBUG, "Rebooting.");
  91
  92         if (flags & REBOOT_DRY_RUN)
  93                 return 0;
  94
  95         (void) reboot(RB_AUTOBOOT);
  96
  97         return log_full_errno(flags & REBOOT_LOG ? LOG_ERR : LOG_DEBUG, errno, "Failed to reboot: %m");
  98 }
  99
 100 int shall_restore_state(void) {
 101         bool ret;
 102         int r;
 103
 104         r = proc_cmdline_get_bool("systemd.restore_state", &ret);
 105         if (r < 0)
 106                 return r;
 107
 108         return r > 0 ? ret : true;
 109 }