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 static int arg_lines = -1;
  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                "  -n --lines=INTEGER  Lines to show\n"
  57                "  -o --output=STRING  Change output mode (short, verbose, export, json)\n",
  58                program_invocation_short_name);
  59
  60         return 0;
  61 }
  62
  63 static int parse_argv(int argc, char *argv[]) {
  64
  65         enum {
  66                 ARG_VERSION = 0x100,
  67                 ARG_NO_PAGER
  68         };
  69
  70         static const struct option options[] = {
  71                 { "help",      no_argument,       NULL, 'h'           },
  72                 { "version" ,  no_argument,       NULL, ARG_VERSION   },
  73                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER  },
  74                 { "follow",    no_argument,       NULL, 'f'           },
  75                 { "output",    required_argument, NULL, 'o'           },
  76                 { "all",       no_argument,       NULL, 'a'           },
  77                 { "lines",     required_argument, NULL, 'n'           },
  78                 { NULL,        0,                 NULL, 0             }
  79         };
  80
  81         int c, r;
  82
  83         assert(argc >= 0);
  84         assert(argv);
  85
  86         while ((c = getopt_long(argc, argv, "hfo:an:", options, NULL)) >= 0) {
  87
  88                 switch (c) {
  89
  90                 case 'h':
  91                         help();
  92                         return 0;
  93
  94                 case ARG_VERSION:
  95                         puts(PACKAGE_STRING);
  96                         puts(DISTRIBUTION);
  97                         puts(SYSTEMD_FEATURES);
  98                         return 0;
  99
 100                 case ARG_NO_PAGER:
 101                         arg_no_pager = true;
 102                         break;
 103
 104                 case 'f':
 105                         arg_follow = true;
 106                         break;
 107
 108                 case 'o':
 109                         if (streq(optarg, "short"))
 110                                 arg_output = OUTPUT_SHORT;
 111                         else if (streq(optarg, "verbose"))
 112                                 arg_output = OUTPUT_VERBOSE;
 113                         else if (streq(optarg, "export"))
 114                                 arg_output = OUTPUT_EXPORT;
 115                         else if (streq(optarg, "json"))
 116                                 arg_output = OUTPUT_JSON;
 117                         else {
 118                                 log_error("Unknown output '%s'.", optarg);
 119                                 return -EINVAL;
 120                         }
 121                         break;
 122
 123                 case 'a':
 124                         arg_show_all = true;
 125                         break;
 126
 127                 case 'n':
 128                         r = safe_atoi(optarg, &arg_lines);
 129                         if (r < 0) {
 130                                 log_error("Failed to parse lines '%s'", optarg);
 131                                 return -EINVAL;
 132                         }
 133                         break;
 134
 135                 case '?':
 136                         return -EINVAL;
 137
 138                 default:
 139                         log_error("Unknown option code %c", c);
 140                         return -EINVAL;
 141                 }
 142         }
 143
 144         return 1;
 145 }
 146
 147 int main(int argc, char *argv[]) {
 148         int r, i, fd;
 149         sd_journal *j = NULL;
 150         unsigned line = 0;
 151
 152         log_parse_environment();
 153         log_open();
 154
 155         r = parse_argv(argc, argv);
 156         if (r <= 0)
 157                 goto finish;
 158
 159         r = sd_journal_open(&j, 0);
 160         if (r < 0) {
 161                 log_error("Failed to open journal: %s", strerror(-r));
 162                 goto finish;
 163         }
 164
 165         for (i = optind; i < argc; i++) {
 166                 r = sd_journal_add_match(j, argv[i], strlen(argv[i]));
 167                 if (r < 0) {
 168                         log_error("Failed to add match: %s", strerror(-r));
 169                         goto finish;
 170                 }
 171         }
 172
 173         fd = sd_journal_get_fd(j);
 174         if (fd < 0) {
 175                 log_error("Failed to get wakeup fd: %s", strerror(-fd));
 176                 goto finish;
 177         }
 178
 179         if (arg_lines >= 0) {
 180                 r = sd_journal_seek_tail(j);
 181                 if (r < 0) {
 182                         log_error("Failed to seek to tail: %s", strerror(-r));
 183                         goto finish;
 184                 }
 185
 186                 r = sd_journal_previous_skip(j, arg_lines);
 187                 if (r < 0) {
 188                         log_error("Failed to iterate through journal: %s", strerror(-r));
 189                         goto finish;
 190                 }
 191         } else {
 192                 r = sd_journal_seek_head(j);
 193                 if (r < 0) {
 194                         log_error("Failed to seek to head: %s", strerror(-r));
 195                         goto finish;
 196                 }
 197         }
 198
 199         if (!arg_no_pager && !arg_follow) {
 200                 columns();
 201                 pager_open();
 202         }
 203
 204         if (arg_output == OUTPUT_JSON) {
 205                 fputc('[', stdout);
 206                 fflush(stdout);
 207         }
 208
 209         for (;;) {
 210                 struct pollfd pollfd;
 211
 212                 for (;;) {
 213                         r = sd_journal_next(j);
 214
 215                         if (r < 0) {
 216                                 log_error("Failed to iterate through journal: %s", strerror(-r));
 217                                 goto finish;
 218                         }
 219
 220                         if (r == 0)
 221                                 break;
 222
 223                         line ++;
 224
 225                         r = output_journal(j, arg_output, line, arg_show_all);
 226                         if (r < 0)
 227                                 goto finish;
 228                 }
 229
 230                 if (!arg_follow)
 231                         break;
 232
 233                 zero(pollfd);
 234                 pollfd.fd = fd;
 235                 pollfd.events = POLLIN;
 236
 237                 if (poll(&pollfd, 1, -1) < 0) {
 238                         if (errno == EINTR)
 239                                 break;
 240
 241                         log_error("poll(): %m");
 242                         r = -errno;
 243                         goto finish;
 244                 }
 245
 246                 r = sd_journal_process(j);
 247                 if (r < 0) {
 248                         log_error("Failed to process: %s", strerror(-r));
 249                         goto finish;
 250                 }
 251         }
 252
 253         if (arg_output == OUTPUT_JSON)
 254                 fputs("\n]\n", stdout);
 255
 256 finish:
 257         if (j)
 258                 sd_journal_close(j);
 259
 260         pager_close();
 261
 262         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 263 }