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 static bool arg_quiet = false;
  49 static bool arg_local = false;
  50
  51 static int help(void) {
  52
  53         printf("%s [OPTIONS...] {COMMAND} ...\n\n"
  54                "Send control commands to or query the journal.\n\n"
  55                "  -h --help           Show this help\n"
  56                "     --version        Show package version\n"
  57                "     --no-pager       Do not pipe output into a pager\n"
  58                "  -a --all            Show all fields, including long and unprintable\n"
  59                "  -f --follow         Follow journal\n"
  60                "  -n --lines=INTEGER  Journal entries to show\n"
  61                "     --no-tail        Show all lines, even in follow mode\n"
  62                "  -o --output=STRING  Change journal output mode (short, short-monotonic,\n"
  63                "                      verbose, export, json, cat)\n"
  64                "  -q --quiet          Don't show privilege warning\n"
  65                "     --new-id128      Generate a new 128 Bit id\n"
  66                "  -l --local          Only local entries\n",
  67                program_invocation_short_name);
  68
  69         return 0;
  70 }
  71
  72 static int parse_argv(int argc, char *argv[]) {
  73
  74         enum {
  75                 ARG_VERSION = 0x100,
  76                 ARG_NO_PAGER,
  77                 ARG_NO_TAIL,
  78                 ARG_NEW_ID128
  79         };
  80
  81         static const struct option options[] = {
  82                 { "help",      no_argument,       NULL, 'h'           },
  83                 { "version" ,  no_argument,       NULL, ARG_VERSION   },
  84                 { "no-pager",  no_argument,       NULL, ARG_NO_PAGER  },
  85                 { "follow",    no_argument,       NULL, 'f'           },
  86                 { "output",    required_argument, NULL, 'o'           },
  87                 { "all",       no_argument,       NULL, 'a'           },
  88                 { "lines",     required_argument, NULL, 'n'           },
  89                 { "no-tail",   no_argument,       NULL, ARG_NO_TAIL   },
  90                 { "new-id128", no_argument,       NULL, ARG_NEW_ID128 },
  91                 { "quiet",     no_argument,       NULL, 'q'           },
  92                 { "local",     no_argument,       NULL, 'l'           },
  93                 { NULL,        0,                 NULL, 0             }
  94         };
  95
  96         int c, r;
  97
  98         assert(argc >= 0);
  99         assert(argv);
 100
 101         while ((c = getopt_long(argc, argv, "hfo:an:ql", options, NULL)) >= 0) {
 102
 103                 switch (c) {
 104
 105                 case 'h':
 106                         help();
 107                         return 0;
 108
 109                 case ARG_VERSION:
 110                         puts(PACKAGE_STRING);
 111                         puts(DISTRIBUTION);
 112                         puts(SYSTEMD_FEATURES);
 113                         return 0;
 114
 115                 case ARG_NO_PAGER:
 116                         arg_no_pager = true;
 117                         break;
 118
 119                 case 'f':
 120                         arg_follow = true;
 121                         break;
 122
 123                 case 'o':
 124                         arg_output =  output_mode_from_string(optarg);
 125                         if (arg_output < 0) {
 126                                 log_error("Unknown output '%s'.", optarg);
 127                                 return -EINVAL;
 128                         }
 129
 130                         break;
 131
 132                 case 'a':
 133                         arg_show_all = true;
 134                         break;
 135
 136                 case 'n':
 137                         r = safe_atoi(optarg, &arg_lines);
 138                         if (r < 0 || arg_lines < 0) {
 139                                 log_error("Failed to parse lines '%s'", optarg);
 140                                 return -EINVAL;
 141                         }
 142                         break;
 143
 144                 case ARG_NO_TAIL:
 145                         arg_no_tail = true;
 146                         break;
 147
 148                 case ARG_NEW_ID128:
 149                         arg_new_id128 = true;
 150                         break;
 151
 152                 case 'q':
 153                         arg_quiet = true;
 154                         break;
 155
 156                 case 'l':
 157                         arg_local = true;
 158                         break;
 159
 160                 case '?':
 161                         return -EINVAL;
 162
 163                 default:
 164                         log_error("Unknown option code %c", c);
 165                         return -EINVAL;
 166                 }
 167         }
 168
 169         if (arg_follow && !arg_no_tail && arg_lines < 0)
 170                 arg_lines = 10;
 171
 172         return 1;
 173 }
 174
 175 static int generate_new_id128(void) {
 176         sd_id128_t id;
 177         int r;
 178         unsigned i;
 179
 180         r = sd_id128_randomize(&id);
 181         if (r < 0) {
 182                 log_error("Failed to generate ID: %s", strerror(-r));
 183                 return r;
 184         }
 185
 186         printf("As string:\n"
 187                SD_ID128_FORMAT_STR "\n\n"
 188                "As UUID:\n"
 189                "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x\n\n"
 190                "As macro:\n"
 191               "#define MESSAGE_XYZ SD_ID128_MAKE(",
 192                SD_ID128_FORMAT_VAL(id),
 193                SD_ID128_FORMAT_VAL(id));
 194
 195         for (i = 0; i < 16; i++)
 196                 printf("%02x%s", id.bytes[i], i != 15 ? "," : "");
 197
 198         fputs(")\n", stdout);
 199
 200         return 0;
 201 }
 202
 203 int main(int argc, char *argv[]) {
 204         int r, i, fd;
 205         sd_journal *j = NULL;
 206         unsigned line = 0;
 207         bool need_seek = false;
 208
 209         log_parse_environment();
 210         log_open();
 211
 212         r = parse_argv(argc, argv);
 213         if (r <= 0)
 214                 goto finish;
 215
 216         if (arg_new_id128) {
 217                 r = generate_new_id128();
 218                 goto finish;
 219         }
 220
 221 #ifdef HAVE_ACL
 222         if (!arg_quiet && geteuid() != 0 && in_group("adm") <= 0)
 223                 log_warning("Showing user generated messages only. Users in the group 'adm' can see all messages. Pass -q to turn this message off.");
 224 #endif
 225
 226         r = sd_journal_open(&j, arg_local ? SD_JOURNAL_LOCAL_ONLY : 0);
 227         if (r < 0) {
 228                 log_error("Failed to open journal: %s", strerror(-r));
 229                 goto finish;
 230         }
 231
 232         for (i = optind; i < argc; i++) {
 233                 r = sd_journal_add_match(j, argv[i], strlen(argv[i]));
 234                 if (r < 0) {
 235                         log_error("Failed to add match: %s", strerror(-r));
 236                         goto finish;
 237                 }
 238         }
 239
 240         fd = sd_journal_get_fd(j);
 241         if (fd < 0) {
 242                 log_error("Failed to get wakeup fd: %s", strerror(-fd));
 243                 goto finish;
 244         }
 245
 246         if (arg_lines >= 0) {
 247                 r = sd_journal_seek_tail(j);
 248                 if (r < 0) {
 249                         log_error("Failed to seek to tail: %s", strerror(-r));
 250                         goto finish;
 251                 }
 252
 253                 r = sd_journal_previous_skip(j, arg_lines);
 254         } else {
 255                 r = sd_journal_seek_head(j);
 256                 if (r < 0) {
 257                         log_error("Failed to seek to head: %s", strerror(-r));
 258                         goto finish;
 259                 }
 260
 261                 r = sd_journal_next(j);
 262         }
 263
 264         if (r < 0) {
 265                 log_error("Failed to iterate through journal: %s", strerror(-r));
 266                 goto finish;
 267         }
 268
 269         if (!arg_no_pager && !arg_follow) {
 270                 columns();
 271                 pager_open();
 272         }
 273
 274         if (arg_output == OUTPUT_JSON) {
 275                 fputc('[', stdout);
 276                 fflush(stdout);
 277         }
 278
 279         for (;;) {
 280                 for (;;) {
 281                         if (need_seek) {
 282                                 r = sd_journal_next(j);
 283                                 if (r < 0) {
 284                                         log_error("Failed to iterate through journal: %s", strerror(-r));
 285                                         goto finish;
 286                                 }
 287                         }
 288
 289                         if (r == 0)
 290                                 break;
 291
 292                         line ++;
 293
 294                         r = output_journal(j, arg_output, line, 0, arg_show_all);
 295                         if (r < 0)
 296                                 goto finish;
 297
 298                         need_seek = true;
 299                 }
 300
 301                 if (!arg_follow)
 302                         break;
 303
 304                 r = fd_wait_for_event(fd, POLLIN, (usec_t) -1);
 305                 if (r < 0) {
 306                         log_error("Couldn't wait for event: %s", strerror(-r));
 307                         goto finish;
 308                 }
 309
 310                 r = sd_journal_process(j);
 311                 if (r < 0) {
 312                         log_error("Failed to process: %s", strerror(-r));
 313                         goto finish;
 314                 }
 315         }
 316
 317         if (arg_output == OUTPUT_JSON)
 318                 fputs("\n]\n", stdout);
 319
 320 finish:
 321         if (j)
 322                 sd_journal_close(j);
 323
 324         pager_close();
 325
 326         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 327 }