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_id128 = 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, short-monotonic,\n"
  61                "                      verbose, export, json, cat)\n"
  62                "     --new-id128      Generate a new 128 Bit id\n",
  63                program_invocation_short_name);
  64
  65         return 0;
  66 }
  67
  68 static int parse_argv(int argc, char *argv[]) {
  69
  70         enum {
  71                 ARG_VERSION = 0x100,
  72                 ARG_NO_PAGER,
  73                 ARG_NO_TAIL,
  74                 ARG_NEW_ID128
  75         };
  76
  77         static const struct option options[] = {
  78                 { "help",      no_argument,       NULL, 'h'           },
  79                 { "version" ,  no_argument,       NULL, ARG_VERSION   },
  80                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER  },
  81                 { "follow",    no_argument,       NULL, 'f'           },
  82                 { "output",    required_argument, NULL, 'o'           },
  83                 { "all",       no_argument,       NULL, 'a'           },
  84                 { "lines",     required_argument, NULL, 'n'           },
  85                 { "no-tail",   no_argument,       NULL, ARG_NO_TAIL   },
  86                 { "new-id128", no_argument,       NULL, ARG_NEW_ID128 },
  87                 { NULL,        0,                 NULL, 0             }
  88         };
  89
  90         int c, r;
  91
  92         assert(argc >= 0);
  93         assert(argv);
  94
  95         while ((c = getopt_long(argc, argv, "hfo:an:", options, NULL)) >= 0) {
  96
  97                 switch (c) {
  98
  99                 case 'h':
 100                         help();
 101                         return 0;
 102
 103                 case ARG_VERSION:
 104                         puts(PACKAGE_STRING);
 105                         puts(DISTRIBUTION);
 106                         puts(SYSTEMD_FEATURES);
 107                         return 0;
 108
 109                 case ARG_NO_PAGER:
 110                         arg_no_pager = true;
 111                         break;
 112
 113                 case 'f':
 114                         arg_follow = true;
 115                         break;
 116
 117                 case 'o':
 118                         arg_output =  output_mode_from_string(optarg);
 119                         if (arg_output < 0) {
 120                                 log_error("Unknown output '%s'.", optarg);
 121                                 return -EINVAL;
 122                         }
 123
 124                         break;
 125
 126                 case 'a':
 127                         arg_show_all = true;
 128                         break;
 129
 130                 case 'n':
 131                         r = safe_atoi(optarg, &arg_lines);
 132                         if (r < 0 || arg_lines < 0) {
 133                                 log_error("Failed to parse lines '%s'", optarg);
 134                                 return -EINVAL;
 135                         }
 136                         break;
 137
 138                 case ARG_NO_TAIL:
 139                         arg_no_tail = true;
 140                         break;
 141
 142                 case ARG_NEW_ID128:
 143                         arg_new_id128 = true;
 144                         break;
 145
 146                 case '?':
 147                         return -EINVAL;
 148
 149                 default:
 150                         log_error("Unknown option code %c", c);
 151                         return -EINVAL;
 152                 }
 153         }
 154
 155         if (arg_follow && !arg_no_tail && arg_lines < 0)
 156                 arg_lines = 10;
 157
 158         return 1;
 159 }
 160
 161 static int generate_new_id128(void) {
 162         sd_id128_t id;
 163         int r;
 164         unsigned i;
 165
 166         r = sd_id128_randomize(&id);
 167         if (r < 0) {
 168                 log_error("Failed to generate ID: %s", strerror(-r));
 169                 return r;
 170         }
 171
 172         printf("As string:\n"
 173                SD_ID128_FORMAT_STR "\n\n"
 174                "As UUID:\n"
 175                "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\n\n"
 176                "As macro:\n"
 177               "#define MESSAGE_XYZ SD_ID128_MAKE(",
 178                SD_ID128_FORMAT_VAL(id),
 179                SD_ID128_FORMAT_VAL(id));
 180
 181         for (i = 0; i < 16; i++)
 182                 printf("%02x%s", id.bytes[i], i != 15 ? "," : "");
 183
 184         fputs(")\n", stdout);
 185
 186         return 0;
 187 }
 188
 189 int main(int argc, char *argv[]) {
 190         int r, i, fd;
 191         sd_journal *j = NULL;
 192         unsigned line = 0;
 193         bool need_seek = false;
 194
 195         log_parse_environment();
 196         log_open();
 197
 198         r = parse_argv(argc, argv);
 199         if (r <= 0)
 200                 goto finish;
 201
 202         if (arg_new_id128) {
 203                 r = generate_new_id128();
 204                 goto finish;
 205         }
 206
 207         r = sd_journal_open(&j, 0);
 208         if (r < 0) {
 209                 log_error("Failed to open journal: %s", strerror(-r));
 210                 goto finish;
 211         }
 212
 213         for (i = optind; i < argc; i++) {
 214                 r = sd_journal_add_match(j, argv[i], strlen(argv[i]));
 215                 if (r < 0) {
 216                         log_error("Failed to add match: %s", strerror(-r));
 217                         goto finish;
 218                 }
 219         }
 220
 221         fd = sd_journal_get_fd(j);
 222         if (fd < 0) {
 223                 log_error("Failed to get wakeup fd: %s", strerror(-fd));
 224                 goto finish;
 225         }
 226
 227         if (arg_lines >= 0) {
 228                 r = sd_journal_seek_tail(j);
 229                 if (r < 0) {
 230                         log_error("Failed to seek to tail: %s", strerror(-r));
 231                         goto finish;
 232                 }
 233
 234                 r = sd_journal_previous_skip(j, arg_lines);
 235         } else {
 236                 r = sd_journal_seek_head(j);
 237                 if (r < 0) {
 238                         log_error("Failed to seek to head: %s", strerror(-r));
 239                         goto finish;
 240                 }
 241
 242                 r = sd_journal_next(j);
 243         }
 244
 245         if (r < 0) {
 246                 log_error("Failed to iterate through journal: %s", strerror(-r));
 247                 goto finish;
 248         }
 249
 250         if (!arg_no_pager && !arg_follow) {
 251                 columns();
 252                 pager_open();
 253         }
 254
 255         if (arg_output == OUTPUT_JSON) {
 256                 fputc('[', stdout);
 257                 fflush(stdout);
 258         }
 259
 260         for (;;) {
 261                 for (;;) {
 262                         if (need_seek) {
 263                                 r = sd_journal_next(j);
 264                                 if (r < 0) {
 265                                         log_error("Failed to iterate through journal: %s", strerror(-r));
 266                                         goto finish;
 267                                 }
 268                         }
 269
 270                         if (r == 0)
 271                                 break;
 272
 273                         line ++;
 274
 275                         r = output_journal(j, arg_output, line, arg_show_all);
 276                         if (r < 0)
 277                                 goto finish;
 278
 279                         need_seek = true;
 280                 }
 281
 282                 if (!arg_follow)
 283                         break;
 284
 285                 r = fd_wait_for_event(fd, POLLIN, (usec_t) -1);
 286                 if (r < 0) {
 287                         log_error("Couldn't wait for event: %s", strerror(-r));
 288                         goto finish;
 289                 }
 290
 291                 r = sd_journal_process(j);
 292                 if (r < 0) {
 293                         log_error("Failed to process: %s", strerror(-r));
 294                         goto finish;
 295                 }
 296         }
 297
 298         if (arg_output == OUTPUT_JSON)
 299                 fputs("\n]\n", stdout);
 300
 301 finish:
 302         if (j)
 303                 sd_journal_close(j);
 304
 305         pager_close();
 306
 307         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 308 }