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