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