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_resume_options = NULL;
  21 static char *arg_root_options = NULL;
  22 static bool arg_noresume = false;
  23
  24 STATIC_DESTRUCTOR_REGISTER(arg_resume_device, freep);
  25 STATIC_DESTRUCTOR_REGISTER(arg_resume_options, freep);
  26 STATIC_DESTRUCTOR_REGISTER(arg_root_options, freep);
  27
  28 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
  29
  30         if (streq(key, "resume")) {
  31                 char *s;
  32
  33                 if (proc_cmdline_value_missing(key, value))
  34                         return 0;
  35
  36                 s = fstab_node_to_udev_node(value);
  37                 if (!s)
  38                         return log_oom();
  39
  40                 free_and_replace(arg_resume_device, s);
  41
  42         } else if (streq(key, "resumeflags")) {
  43
  44                 if (proc_cmdline_value_missing(key, value))
  45                         return 0;
  46
  47                 if (!strextend_with_separator(&arg_resume_options, ",", value, NULL))
  48                         return log_oom();
  49
  50         } else if (streq(key, "rootflags")) {
  51
  52                 if (proc_cmdline_value_missing(key, value))
  53                         return 0;
  54
  55                 if (!strextend_with_separator(&arg_root_options, ",", value, NULL))
  56                         return log_oom();
  57
  58         } else if (streq(key, "noresume")) {
  59                 if (value) {
  60                         log_warning("\"noresume\" kernel command line switch specified with an argument, ignoring.");
  61                         return 0;
  62                 }
  63
  64                 arg_noresume = true;
  65         }
  66
  67         return 0;
  68 }
  69
  70 static int process_resume(void) {
  71         _cleanup_free_ char *name = NULL, *lnk = NULL;
  72         const char *opts;
  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", &name);
  79         if (r < 0)
  80                 return log_error_errno(r, "Failed to generate unit name: %m");
  81
  82         lnk = strjoin(arg_dest, "/" SPECIAL_SYSINIT_TARGET ".wants/", name);
  83         if (!lnk)
  84                 return log_oom();
  85
  86         mkdir_parents_label(lnk, 0755);
  87         if (symlink(SYSTEM_DATA_UNIT_PATH "/systemd-hibernate-resume@.service", lnk) < 0)
  88                 return log_error_errno(errno, "Failed to create symlink %s: %m", lnk);
  89
  90         if (arg_resume_options)
  91                 opts = arg_resume_options;
  92         else
  93                 opts = arg_root_options;
  94
  95         r = generator_write_timeouts(arg_dest, arg_resume_device, arg_resume_device, opts, NULL);
  96         if (r < 0)
  97                 return r;
  98
  99         return 0;
 100 }
 101
 102 static int run(int argc, char *argv[]) {
 103         int r = 0;
 104
 105         log_setup_generator();
 106
 107         if (argc > 1 && argc != 4)
 108                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
 109                                        "This program takes three or no arguments.");
 110
 111         if (argc > 1)
 112                 arg_dest = argv[1];
 113
 114         /* Don't even consider resuming outside of initramfs. */
 115         if (!in_initrd()) {
 116                 log_debug("Not running in an initrd, quitting.");
 117                 return 0;
 118         }
 119
 120         r = proc_cmdline_parse(parse_proc_cmdline_item, NULL, 0);
 121         if (r < 0)
 122                 log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m");
 123
 124         if (arg_noresume) {
 125                 log_notice("Found \"noresume\" on the kernel command line, quitting.");
 126                 return 0;
 127         }
 128
 129         return process_resume();
 130 }
 131
 132 DEFINE_MAIN_FUNCTION(run);