src/hibernate-resume/hibernate-resume-generator.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <errno.h>
   4 #include <stdio.h>
   5 #include <unistd.h>
   6
   7 #include "alloc-util.h"
   8 #include "dropin.h"
   9 #include "fstab-util.h"
  10 #include "generator.h"
  11 #include "log.h"
  12 #include "main-func.h"
  13 #include "mkdir.h"
  14 #include "proc-cmdline.h"
  15 #include "special.h"
  16 #include "string-util.h"
  17 #include "unit-name.h"
  18
  19 static const char *arg_dest = "/tmp";
  20 static char *arg_resume_device = NULL;
  21 static char *arg_resume_options = NULL;
  22 static char *arg_root_options = NULL;
  23 static bool arg_noresume = false;
  24
  25 STATIC_DESTRUCTOR_REGISTER(arg_resume_device, freep);
  26 STATIC_DESTRUCTOR_REGISTER(arg_resume_options, freep);
  27 STATIC_DESTRUCTOR_REGISTER(arg_root_options, freep);
  28
  29 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
  30
  31         if (streq(key, "resume")) {
  32                 char *s;
  33
  34                 if (proc_cmdline_value_missing(key, value))
  35                         return 0;
  36
  37                 s = fstab_node_to_udev_node(value);
  38                 if (!s)
  39                         return log_oom();
  40
  41                 free_and_replace(arg_resume_device, s);
  42
  43         } else if (streq(key, "resumeflags")) {
  44
  45                 if (proc_cmdline_value_missing(key, value))
  46                         return 0;
  47
  48                 if (!strextend_with_separator(&arg_resume_options, ",", value, NULL))
  49                         return log_oom();
  50
  51         } else if (streq(key, "rootflags")) {
  52
  53                 if (proc_cmdline_value_missing(key, value))
  54                         return 0;
  55
  56                 if (!strextend_with_separator(&arg_root_options, ",", value, NULL))
  57                         return log_oom();
  58
  59         } else if (streq(key, "noresume")) {
  60                 if (value) {
  61                         log_warning("\"noresume\" kernel command line switch specified with an argument, ignoring.");
  62                         return 0;
  63                 }
  64
  65                 arg_noresume = true;
  66         }
  67
  68         return 0;
  69 }
  70
  71 static int process_resume(void) {
  72         _cleanup_free_ char *service_unit = NULL, *device_unit = NULL, *lnk = NULL;
  73         int r;
  74
  75         if (!arg_resume_device)
  76                 return 0;
  77
  78         r = unit_name_from_path_instance("systemd-hibernate-resume", arg_resume_device, ".service",
  79                                          &service_unit);
  80         if (r < 0)
  81                 return log_error_errno(r, "Failed to generate unit name: %m");
  82
  83         lnk = strjoin(arg_dest, "/" SPECIAL_SYSINIT_TARGET ".wants/", service_unit);
  84         if (!lnk)
  85                 return log_oom();
  86
  87         mkdir_parents_label(lnk, 0755);
  88         if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-hibernate-resume@.service", lnk) < 0)
  89                 return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
  90
  91         r = unit_name_from_path(arg_resume_device, ".device", &device_unit);
  92         if (r < 0)
  93                 return log_error_errno(r, "Failed to generate unit name: %m");
  94
  95         r = write_drop_in(arg_dest, device_unit, 40, "device-timeout",
  96                           "# Automatically generated by systemd-hibernate-resume-generator\n\n"
  97                           "[Unit]\nJobTimeoutSec=0");
  98         if (r < 0)
  99                 log_warning_errno(r, "Failed to write device timeout drop-in: %m");
 100
 101         r = generator_write_timeouts(arg_dest,
 102                                      arg_resume_device,
 103                                      arg_resume_device,
 104                                      arg_resume_options ?: arg_root_options,
 105                                      NULL);
 106         if (r < 0)
 107                 return r;
 108
 109         return 0;
 110 }
 111
 112 static int run(int argc, char *argv[]) {
 113         int r = 0;
 114
 115         log_setup_generator();
 116
 117         if (argc > 1 && argc != 4)
 118                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 119                                        "This program takes three or no arguments.");
 120
 121         if (argc > 1)
 122                 arg_dest = argv[1];
 123
 124         /* Don't even consider resuming outside of initramfs. */
 125         if (!in_initrd()) {
 126                 log_debug("Not running in an initrd, quitting.");
 127                 return 0;
 128         }
 129
 130         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
 131         if (r < 0)
 132                 log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 133
 134         if (arg_noresume) {
 135                 log_notice("Found \"noresume\" on the kernel command line, quitting.");
 136                 return 0;
 137         }
 138
 139         return process_resume();
 140 }
 141
 142 DEFINE_MAIN_FUNCTION(run);