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