src/journal/journalctl.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2011 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 <fcntl.h>
  23 #include <errno.h>
  24 #include <stddef.h>
  25 #include <string.h>
  26 #include <stdio.h>
  27 #include <unistd.h>
  28 #include <stdlib.h>
  29 #include <sys/poll.h>
  30 #include <time.h>
  31 #include <getopt.h>
  32
  33 #include "sd-journal.h"
  34 #include "log.h"
  35 #include "util.h"
  36 #include "build.h"
  37 #include "pager.h"
  38 #include "logs-show.h"
  39
  40 static output_mode arg_output = OUTPUT_SHORT;
  41
  42 static bool arg_follow = false;
  43 static bool arg_show_all = false;
  44 static bool arg_no_pager = false;
  45
  46
  47 static int help(void) {
  48
  49         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
  50                "Send control commands to or query the login manager.\n\n"
  51                "  -h --help           Show this help\n"
  52                "     --version        Show package version\n"
  53                "     --no-pager       Do not pipe output into a pager\n"
  54                "  -a --all            Show all properties, including long and unprintable\n"
  55                "  -f --follow         Follow journal\n"
  56                "  -o --output=STRING  Change output mode (short, verbose, export, json)\n",
  57                program_invocation_short_name);
  58
  59         return 0;
  60 }
  61
  62 static int parse_argv(int argc, char *argv[]) {
  63
  64         enum {
  65                 ARG_VERSION = 0x100,
  66                 ARG_NO_PAGER
  67         };
  68
  69         static const struct option options[] = {
  70                 { "help",      no_argument,       NULL, 'h'           },
  71                 { "version" ,  no_argument,       NULL, ARG_VERSION   },
  72                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER  },
  73                 { "follow",    no_argument,       NULL, 'f'           },
  74                 { "output",    required_argument, NULL, 'o'           },
  75                 { "all",       no_argument,       NULL, 'a'           },
  76                 { NULL,        0,                 NULL, 0             }
  77         };
  78
  79         int c;
  80
  81         assert(argc >= 0);
  82         assert(argv);
  83
  84         while ((c = getopt_long(argc, argv, "hfo:a", options, NULL)) >= 0) {
  85
  86                 switch (c) {
  87
  88                 case 'h':
  89                         help();
  90                         return 0;
  91
  92                 case ARG_VERSION:
  93                         puts(PACKAGE_STRING);
  94                         puts(DISTRIBUTION);
  95                         puts(SYSTEMD_FEATURES);
  96                         return 0;
  97
  98                 case ARG_NO_PAGER:
  99                         arg_no_pager = true;
 100                         break;
 101
 102                 case 'f':
 103                         arg_follow = true;
 104                         break;
 105
 106                 case 'o':
 107                         if (streq(optarg, "short"))
 108                                 arg_output = OUTPUT_SHORT;
 109                         else if (streq(optarg, "verbose"))
 110                                 arg_output = OUTPUT_VERBOSE;
 111                         else if (streq(optarg, "export"))
 112                                 arg_output = OUTPUT_EXPORT;
 113                         else if (streq(optarg, "json"))
 114                                 arg_output = OUTPUT_JSON;
 115                         else {
 116                                 log_error("Unknown output '%s'.", optarg);
 117                                 return -EINVAL;
 118                         }
 119                         break;
 120
 121                 case 'a':
 122                         arg_show_all = true;
 123                         break;
 124
 125                 case '?':
 126                         return -EINVAL;
 127
 128                 default:
 129                         log_error("Unknown option code %c", c);
 130                         return -EINVAL;
 131                 }
 132         }
 133
 134         return 1;
 135 }
 136
 137 int main(int argc, char *argv[]) {
 138         int r, i, fd;
 139         sd_journal *j = NULL;
 140         unsigned line = 0;
 141
 142         log_parse_environment();
 143         log_open();
 144
 145         r = parse_argv(argc, argv);
 146         if (r <= 0)
 147                 goto finish;
 148
 149         r = sd_journal_open(&j, 0);
 150         if (r < 0) {
 151                 log_error("Failed to open journal: %s", strerror(-r));
 152                 goto finish;
 153         }
 154
 155         for (i = optind; i < argc; i++) {
 156                 r = sd_journal_add_match(j, argv[i], strlen(argv[i]));
 157                 if (r < 0) {
 158                         log_error("Failed to add match: %s", strerror(-r));
 159                         goto finish;
 160                 }
 161         }
 162
 163         fd = sd_journal_get_fd(j);
 164         if (fd < 0) {
 165                 log_error("Failed to get wakeup fd: %s", strerror(-fd));
 166                 goto finish;
 167         }
 168
 169         r = sd_journal_seek_head(j);
 170         if (r < 0) {
 171                 log_error("Failed to seek to head: %s", strerror(-r));
 172                 goto finish;
 173         }
 174
 175         if (!arg_no_pager && !arg_follow) {
 176                 columns();
 177                 pager_open();
 178         }
 179
 180         if (arg_output == OUTPUT_JSON) {
 181                 fputc('[', stdout);
 182                 fflush(stdout);
 183         }
 184
 185         for (;;) {
 186                 struct pollfd pollfd;
 187
 188                 for (;;) {
 189                         r = sd_journal_next(j);
 190
 191                         if (r < 0) {
 192                                 log_error("Failed to iterate through journal: %s", strerror(-r));
 193                                 goto finish;
 194                         }
 195
 196                         if (r == 0)
 197                                 break;
 198
 199                         line ++;
 200
 201                         r = output_journal(j, arg_output, line, arg_show_all);
 202                         if (r < 0)
 203                                 goto finish;
 204                 }
 205
 206                 if (!arg_follow)
 207                         break;
 208
 209                 zero(pollfd);
 210                 pollfd.fd = fd;
 211                 pollfd.events = POLLIN;
 212
 213                 if (poll(&pollfd, 1, -1) < 0) {
 214                         if (errno == EINTR)
 215                                 break;
 216
 217                         log_error("poll(): %m");
 218                         r = -errno;
 219                         goto finish;
 220                 }
 221
 222                 r = sd_journal_process(j);
 223                 if (r < 0) {
 224                         log_error("Failed to process: %s", strerror(-r));
 225                         goto finish;
 226                 }
 227         }
 228
 229         if (arg_output == OUTPUT_JSON)
 230                 fputs("\n]\n", stdout);
 231
 232 finish:
 233         if (j)
 234                 sd_journal_close(j);
 235
 236         pager_close();
 237
 238         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 239 }