src/notify.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <stdio.h>
  23 #include <getopt.h>
  24 #include <error.h>
  25 #include <errno.h>
  26 #include <unistd.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29
  30 #include "strv.h"
  31 #include "util.h"
  32 #include "log.h"
  33 #include "sd-daemon.h"
  34
  35 static bool arg_ready = false;
  36 static pid_t arg_pid = 0;
  37 static const char *arg_status = NULL;
  38 static bool arg_booted = false;
  39 static const char *arg_readahead = NULL;
  40
  41 static int help(void) {
  42
  43         printf("%s [OPTIONS...] [VARIABLE=VALUE...]\n\n"
  44                "Notify the init system about service status updates.\n\n"
  45                "  -h --help             Show this help\n"
  46                "     --ready            Inform the init system about service start-up completion\n"
  47                "     --pid[=PID]        Set main pid of daemon\n"
  48                "     --status=TEXT      Set status text\n"
  49                "     --booted           Returns 0 if the system was booted up with systemd, non-zero otherwise\n"
  50                "     --readahead=ACTION Controls read-ahead operations\n",
  51                program_invocation_short_name);
  52
  53         return 0;
  54 }
  55
  56 static int parse_argv(int argc, char *argv[]) {
  57
  58         enum {
  59                 ARG_READY = 0x100,
  60                 ARG_PID,
  61                 ARG_STATUS,
  62                 ARG_BOOTED,
  63                 ARG_READAHEAD
  64         };
  65
  66         static const struct option options[] = {
  67                 { "help",      no_argument,       NULL, 'h'           },
  68                 { "ready",     no_argument,       NULL, ARG_READY     },
  69                 { "pid",       optional_argument, NULL, ARG_PID       },
  70                 { "status",    required_argument, NULL, ARG_STATUS    },
  71                 { "booted",    no_argument,       NULL, ARG_BOOTED    },
  72                 { "readahead", required_argument, NULL, ARG_READAHEAD },
  73                 { NULL,        0,                 NULL, 0             }
  74         };
  75
  76         int c;
  77
  78         assert(argc >= 0);
  79         assert(argv);
  80
  81         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
  82
  83                 switch (c) {
  84
  85                 case 'h':
  86                         help();
  87                         return 0;
  88
  89                 case ARG_READY:
  90                         arg_ready = true;
  91                         break;
  92
  93                 case ARG_PID:
  94
  95                         if (optarg) {
  96                                 if (parse_pid(optarg, &arg_pid) < 0) {
  97                                         log_error("Failed to parse PID %s.", optarg);
  98                                         return -EINVAL;
  99                                 }
 100                         } else
 101                                 arg_pid = getppid();
 102
 103                         break;
 104
 105                 case ARG_STATUS:
 106                         arg_status = optarg;
 107                         break;
 108
 109                 case ARG_BOOTED:
 110                         arg_booted = true;
 111                         break;
 112
 113                 case ARG_READAHEAD:
 114                         arg_readahead = optarg;
 115                         break;
 116
 117                 case '?':
 118                         return -EINVAL;
 119
 120                 default:
 121                         log_error("Unknown option code %c", c);
 122                         return -EINVAL;
 123                 }
 124         }
 125
 126         if (optind >= argc &&
 127             !arg_ready &&
 128             !arg_status &&
 129             !arg_pid &&
 130             !arg_booted &&
 131             !arg_readahead) {
 132                 help();
 133                 return -EINVAL;
 134         }
 135
 136         return 1;
 137 }
 138
 139 int main(int argc, char* argv[]) {
 140         char* our_env[4], **final_env = NULL;
 141         unsigned i = 0;
 142         char *status = NULL, *cpid = NULL, *n = NULL;
 143         int r, retval = EXIT_FAILURE;
 144
 145         log_parse_environment();
 146         log_open();
 147
 148         if ((r = parse_argv(argc, argv)) <= 0) {
 149                 retval = r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 150                 goto finish;
 151         }
 152
 153         if (arg_booted)
 154                 return sd_booted() <= 0;
 155
 156         if (arg_readahead) {
 157                 if ((r = sd_readahead(arg_readahead)) < 0) {
 158                         log_error("Failed to issue read-ahead control command: %s", strerror(-r));
 159                         goto finish;
 160                 }
 161         }
 162
 163         if (arg_ready)
 164                 our_env[i++] = (char*) "READY=1";
 165
 166         if (arg_status) {
 167                 if (!(status = strappend("STATUS=", arg_status))) {
 168                         log_error("Failed to allocate STATUS string.");
 169                         goto finish;
 170                 }
 171
 172                 our_env[i++] = status;
 173         }
 174
 175         if (arg_pid > 0) {
 176                 if (asprintf(&cpid, "MAINPID=%lu", (unsigned long) arg_pid) < 0) {
 177                         log_error("Failed to allocate MAINPID string.");
 178                         goto finish;
 179                 }
 180
 181                 our_env[i++] = cpid;
 182         }
 183
 184         our_env[i++] = NULL;
 185
 186         if (!(final_env = strv_env_merge(2, our_env, argv + optind))) {
 187                 log_error("Failed to merge string sets.");
 188                 goto finish;
 189         }
 190
 191         if (strv_length(final_env) <= 0) {
 192                 retval = EXIT_SUCCESS;
 193                 goto finish;
 194         }
 195
 196         if (!(n = strv_join(final_env, "\n"))) {
 197                 log_error("Failed to concatenate strings.");
 198                 goto finish;
 199         }
 200
 201         if ((r = sd_notify(false, n)) < 0) {
 202                 log_error("Failed to notify init system: %s", strerror(-r));
 203                 goto finish;
 204         }
 205
 206         retval = r <= 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 207
 208 finish:
 209         free(status);
 210         free(cpid);
 211         free(n);
 212
 213         strv_free(final_env);
 214
 215         return retval;
 216 }