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 <systemd/sd-journal.h>
  34
  35 #include "log.h"
  36 #include "util.h"
  37 #include "build.h"
  38 #include "pager.h"
  39 #include "logs-show.h"
  40
  41 static OutputMode arg_output = OUTPUT_SHORT;
  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 static bool arg_no_tail = false;
  47 static bool arg_new_id = false;
  48
  49 static int help(void) {
  50
  51         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
  52                "Send control commands to or query the journal.\n\n"
  53                "  -h --help           Show this help\n"
  54                "     --version        Show package version\n"
  55                "     --no-pager       Do not pipe output into a pager\n"
  56                "  -a --all            Show all properties, including long and unprintable\n"
  57                "  -f --follow         Follow journal\n"
  58                "  -n --lines=INTEGER  Journal entries to show\n"
  59                "     --no-tail        Show all lines, even in follow mode\n"
  60                "  -o --output=STRING  Change journal output mode (short, verbose, export, json)\n"
  61                "     --new-id         Generate a new 128 Bit id\n",
  62                program_invocation_short_name);
  63
  64         return 0;
  65 }
  66
  67 static int parse_argv(int argc, char *argv[]) {
  68
  69         enum {
  70                 ARG_VERSION = 0x100,
  71                 ARG_NO_PAGER,
  72                 ARG_NO_TAIL,
  73                 ARG_NEW_ID
  74         };
  75
  76         static const struct option options[] = {
  77                 { "help",      no_argument,       NULL, 'h'           },
  78                 { "version" ,  no_argument,       NULL, ARG_VERSION   },
  79                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER  },
  80                 { "follow",    no_argument,       NULL, 'f'           },
  81                 { "output",    required_argument, NULL, 'o'           },
  82                 { "all",       no_argument,       NULL, 'a'           },
  83                 { "lines",     required_argument, NULL, 'n'           },
  84                 { "no-tail",   no_argument,       NULL, ARG_NO_TAIL   },
  85                 { "new-id",    no_argument,       NULL, ARG_NEW_ID    },
  86                 { NULL,        0,                 NULL, 0             }
  87         };
  88
  89         int c, r;
  90
  91         assert(argc >= 0);
  92         assert(argv);
  93
  94         while ((c = getopt_long(argc, argv, "hfo:an:", options, NULL)) >= 0) {
  95
  96                 switch (c) {
  97
  98                 case 'h':
  99                         help();
 100                         return 0;
 101
 102                 case ARG_VERSION:
 103                         puts(PACKAGE_STRING);
 104                         puts(DISTRIBUTION);
 105                         puts(SYSTEMD_FEATURES);
 106                         return 0;
 107
 108                 case ARG_NO_PAGER:
 109                         arg_no_pager = true;
 110                         break;
 111
 112                 case 'f':
 113                         arg_follow = true;
 114                         break;
 115
 116                 case 'o':
 117                         arg_output =  output_mode_from_string(optarg);
 118                         if (arg_output < 0) {
 119                                 log_error("Unknown output '%s'.", optarg);
 120                                 return -EINVAL;
 121                         }
 122
 123                         break;
 124
 125                 case 'a':
 126                         arg_show_all = true;
 127                         break;
 128
 129                 case 'n':
 130                         r = safe_atoi(optarg, &arg_lines);
 131                         if (r < 0 || arg_lines < 0) {
 132                                 log_error("Failed to parse lines '%s'", optarg);
 133                                 return -EINVAL;
 134                         }
 135                         break;
 136
 137                 case ARG_NO_TAIL:
 138                         arg_no_tail = true;
 139                         break;
 140
 141                 case ARG_NEW_ID:
 142                         arg_new_id = true;
 143                         break;
 144
 145                 case '?':
 146                         return -EINVAL;
 147
 148                 default:
 149                         log_error("Unknown option code %c", c);
 150                         return -EINVAL;
 151                 }
 152         }
 153
 154         if (arg_follow && !arg_no_tail)
 155                 arg_lines = 10;
 156
 157         return 1;
 158 }
 159
 160 static int generate_new_id(void) {
 161         sd_id128_t id;
 162         int r;
 163         unsigned i;
 164
 165         r = sd_id128_randomize(&id);
 166         if (r < 0) {
 167                 log_error("Failed to generate ID: %s", strerror(-r));
 168                 return r;
 169         }
 170
 171         printf("As string:\n"
 172                SD_ID128_FORMAT_STR "\n\n"
 173                "As UUID:\n"
 174                "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\n\n"
 175                "As macro:\n"
 176               "#define MESSAGE_XYZ SD_ID128_MAKE(",
 177                SD_ID128_FORMAT_VAL(id),
 178                SD_ID128_FORMAT_VAL(id));
 179
 180         for (i = 0; i < 16; i++)
 181                 printf("%02x%s", id.bytes[i], i != 15 ? "," : "");
 182
 183         fputs(")\n", stdout);
 184
 185         return 0;
 186 }
 187
 188 int main(int argc, char *argv[]) {
 189         int r, i, fd;
 190         sd_journal *j = NULL;
 191         unsigned line = 0;
 192         bool need_seek = false;
 193
 194         log_parse_environment();
 195         log_open();
 196
 197         r = parse_argv(argc, argv);
 198         if (r <= 0)
 199                 goto finish;
 200
 201         if (arg_new_id) {
 202                 r = generate_new_id();
 203                 goto finish;
 204         }
 205
 206         r = sd_journal_open(&j, 0);
 207         if (r < 0) {
 208                 log_error("Failed to open journal: %s", strerror(-r));
 209                 goto finish;
 210         }
 211
 212         for (i = optind; i < argc; i++) {
 213                 r = sd_journal_add_match(j, argv[i], strlen(argv[i]));
 214                 if (r < 0) {
 215                         log_error("Failed to add match: %s", strerror(-r));
 216                         goto finish;
 217                 }
 218         }
 219
 220         fd = sd_journal_get_fd(j);
 221         if (fd < 0) {
 222                 log_error("Failed to get wakeup fd: %s", strerror(-fd));
 223                 goto finish;
 224         }
 225
 226         if (arg_lines >= 0) {
 227                 r = sd_journal_seek_tail(j);
 228                 if (r < 0) {
 229                         log_error("Failed to seek to tail: %s", strerror(-r));
 230                         goto finish;
 231                 }
 232
 233                 r = sd_journal_previous_skip(j, arg_lines);
 234         } else {
 235                 r = sd_journal_seek_head(j);
 236                 if (r < 0) {
 237                         log_error("Failed to seek to head: %s", strerror(-r));
 238                         goto finish;
 239                 }
 240
 241                 r = sd_journal_next(j);
 242         }
 243
 244         if (r < 0) {
 245                 log_error("Failed to iterate through journal: %s", strerror(-r));
 246                 goto finish;
 247         }
 248
 249         if (!arg_no_pager && !arg_follow) {
 250                 columns();
 251                 pager_open();
 252         }
 253
 254         if (arg_output == OUTPUT_JSON) {
 255                 fputc('[', stdout);
 256                 fflush(stdout);
 257         }
 258
 259         for (;;) {
 260                 for (;;) {
 261                         if (need_seek) {
 262                                 r = sd_journal_next(j);
 263                                 if (r < 0) {
 264                                         log_error("Failed to iterate through journal: %s", strerror(-r));
 265                                         goto finish;
 266                                 }
 267                         }
 268
 269                         if (r == 0)
 270                                 break;
 271
 272                         line ++;
 273
 274                         r = output_journal(j, arg_output, line, arg_show_all);
 275                         if (r < 0)
 276                                 goto finish;
 277
 278                         need_seek = true;
 279                 }
 280
 281                 if (!arg_follow)
 282                         break;
 283
 284                 r = fd_wait_for_event(fd, POLLIN);
 285                 if (r < 0) {
 286                         log_error("Couldn't wait for event: %s", strerror(-r));
 287                         goto finish;
 288                 }
 289
 290                 r = sd_journal_process(j);
 291                 if (r < 0) {
 292                         log_error("Failed to process: %s", strerror(-r));
 293                         goto finish;
 294                 }
 295         }
 296
 297         if (arg_output == OUTPUT_JSON)
 298                 fputs("\n]\n", stdout);
 299
 300 finish:
 301         if (j)
 302                 sd_journal_close(j);
 303
 304         pager_close();
 305
 306         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 307 }