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 <systemd/sd-daemon.h>
  31
  32 #include "strv.h"
  33 #include "util.h"
  34 #include "log.h"
  35 #include "sd-readahead.h"
  36 #include "build.h"
  37
  38 static bool arg_ready = false;
  39 static pid_t arg_pid = 0;
  40 static const char *arg_status = NULL;
  41 static bool arg_booted = false;
  42 static const char *arg_readahead = NULL;
  43
  44 static int help(void) {
  45
  46         printf("%s [OPTIONS...] [VARIABLE=VALUE...]\n\n"
  47                "Notify the init system about service status updates.\n\n"
  48                "  -h --help             Show this help\n"
  49                "     --version          Show package version\n"
  50                "     --ready            Inform the init system about service start-up completion\n"
  51                "     --pid[=PID]        Set main pid of daemon\n"
  52                "     --status=TEXT      Set status text\n"
  53                "     --booted           Returns 0 if the system was booted up with systemd, non-zero otherwise\n"
  54                "     --readahead=ACTION Controls read-ahead operations\n",
  55                program_invocation_short_name);
  56
  57         return 0;
  58 }
  59
  60 static int parse_argv(int argc, char *argv[]) {
  61
  62         enum {
  63                 ARG_READY = 0x100,
  64                 ARG_VERSION,
  65                 ARG_PID,
  66                 ARG_STATUS,
  67                 ARG_BOOTED,
  68                 ARG_READAHEAD
  69         };
  70
  71         static const struct option options[] = {
  72                 { "help",      no_argument,       NULL, 'h'           },
  73                 { "version",   no_argument,       NULL, ARG_VERSION   },
  74                 { "ready",     no_argument,       NULL, ARG_READY     },
  75                 { "pid",       optional_argument, NULL, ARG_PID       },
  76                 { "status",    required_argument, NULL, ARG_STATUS    },
  77                 { "booted",    no_argument,       NULL, ARG_BOOTED    },
  78                 { "readahead", required_argument, NULL, ARG_READAHEAD },
  79                 { NULL,        0,                 NULL, 0             }
  80         };
  81
  82         int c;
  83
  84         assert(argc >= 0);
  85         assert(argv);
  86
  87         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
  88
  89                 switch (c) {
  90
  91                 case 'h':
  92                         help();
  93                         return 0;
  94
  95                 case ARG_VERSION:
  96                         puts(PACKAGE_STRING);
  97                         puts(DISTRIBUTION);
  98                         puts(SYSTEMD_FEATURES);
  99                         return 0;
 100
 101                 case ARG_READY:
 102                         arg_ready = true;
 103                         break;
 104
 105                 case ARG_PID:
 106
 107                         if (optarg) {
 108                                 if (parse_pid(optarg, &arg_pid) < 0) {
 109                                         log_error("Failed to parse PID %s.", optarg);
 110                                         return -EINVAL;
 111                                 }
 112                         } else
 113                                 arg_pid = getppid();
 114
 115                         break;
 116
 117                 case ARG_STATUS:
 118                         arg_status = optarg;
 119                         break;
 120
 121                 case ARG_BOOTED:
 122                         arg_booted = true;
 123                         break;
 124
 125                 case ARG_READAHEAD:
 126                         arg_readahead = optarg;
 127                         break;
 128
 129                 case '?':
 130                         return -EINVAL;
 131
 132                 default:
 133                         log_error("Unknown option code %c", c);
 134                         return -EINVAL;
 135                 }
 136         }
 137
 138         if (optind >= argc &&
 139             !arg_ready &&
 140             !arg_status &&
 141             !arg_pid &&
 142             !arg_booted &&
 143             !arg_readahead) {
 144                 help();
 145                 return -EINVAL;
 146         }
 147
 148         return 1;
 149 }
 150
 151 int main(int argc, char* argv[]) {
 152         char* our_env[4], **final_env = NULL;
 153         unsigned i = 0;
 154         char *status = NULL, *cpid = NULL, *n = NULL;
 155         int r, retval = EXIT_FAILURE;
 156
 157         log_parse_environment();
 158         log_open();
 159
 160         if ((r = parse_argv(argc, argv)) <= 0) {
 161                 retval = r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 162                 goto finish;
 163         }
 164
 165         if (arg_booted)
 166                 return sd_booted() <= 0;
 167
 168         if (arg_readahead) {
 169                 if ((r = sd_readahead(arg_readahead)) < 0) {
 170                         log_error("Failed to issue read-ahead control command: %s", strerror(-r));
 171                         goto finish;
 172                 }
 173         }
 174
 175         if (arg_ready)
 176                 our_env[i++] = (char*) "READY=1";
 177
 178         if (arg_status) {
 179                 if (!(status = strappend("STATUS=", arg_status))) {
 180                         log_error("Failed to allocate STATUS string.");
 181                         goto finish;
 182                 }
 183
 184                 our_env[i++] = status;
 185         }
 186
 187         if (arg_pid > 0) {
 188                 if (asprintf(&cpid, "MAINPID=%lu", (unsigned long) arg_pid) < 0) {
 189                         log_error("Failed to allocate MAINPID string.");
 190                         goto finish;
 191                 }
 192
 193                 our_env[i++] = cpid;
 194         }
 195
 196         our_env[i++] = NULL;
 197
 198         if (!(final_env = strv_env_merge(2, our_env, argv + optind))) {
 199                 log_error("Failed to merge string sets.");
 200                 goto finish;
 201         }
 202
 203         if (strv_length(final_env) <= 0) {
 204                 retval = EXIT_SUCCESS;
 205                 goto finish;
 206         }
 207
 208         if (!(n = strv_join(final_env, "\n"))) {
 209                 log_error("Failed to concatenate strings.");
 210                 goto finish;
 211         }
 212
 213         if ((r = sd_notify(false, n)) < 0) {
 214                 log_error("Failed to notify init system: %s", strerror(-r));
 215                 goto finish;
 216         }
 217
 218         retval = r <= 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 219
 220 finish:
 221         free(status);
 222         free(cpid);
 223         free(n);
 224
 225         strv_free(final_env);
 226
 227         return retval;
 228 }