src/ac-power/ac-power.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <getopt.h>
   4
   5 #include "main-func.h"
   6 #include "util.h"
   7
   8 static bool arg_verbose = false;
   9
  10 static void help(void) {
  11         printf("%s\n\n"
  12                "Report whether we are connected to an external power source.\n\n"
  13                "  -h --help             Show this help\n"
  14                "     --version          Show package version\n"
  15                "  -v --verbose          Show state as text\n"
  16                , program_invocation_short_name);
  17 }
  18
  19 static int parse_argv(int argc, char *argv[]) {
  20
  21         enum {
  22                 ARG_VERSION = 0x100,
  23         };
  24
  25         static const struct option options[] = {
  26                 { "help",    no_argument, NULL, 'h'         },
  27                 { "version", no_argument, NULL, ARG_VERSION },
  28                 { "verbose", no_argument, NULL, 'v'         },
  29                 {}
  30         };
  31
  32         int c;
  33
  34         assert(argc >= 0);
  35         assert(argv);
  36
  37         while ((c = getopt_long(argc, argv, "hv", options, NULL)) >= 0)
  38
  39                 switch (c) {
  40
  41                 case 'h':
  42                         help();
  43                         return 0;
  44
  45                 case ARG_VERSION:
  46                         return version();
  47
  48                 case 'v':
  49                         arg_verbose = true;
  50                         break;
  51
  52                 case '?':
  53                         return -EINVAL;
  54
  55                 default:
  56                         assert_not_reached("Unhandled option");
  57                 }
  58
  59         if (optind < argc)
  60                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
  61                                        "%s takes no arguments.",
  62                                        program_invocation_short_name);
  63
  64         return 1;
  65 }
  66
  67 static int run(int argc, char *argv[]) {
  68         int r;
  69
  70         /* This is mostly intended to be used for scripts which want
  71          * to detect whether AC power is plugged in or not. */
  72
  73         log_parse_environment();
  74         log_open();
  75
  76         r = parse_argv(argc, argv);
  77         if (r <= 0)
  78                 return r;
  79
  80         r = on_ac_power();
  81         if (r < 0)
  82                 return log_error_errno(r, "Failed to read AC status: %m");
  83
  84         if (arg_verbose)
  85                 puts(yes_no(r));
  86
  87         return r == 0;
  88 }
  89
  90 DEFINE_MAIN_FUNCTION_WITH_POSITIVE_FAILURE(run);