src/journal/journald.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2011 Lennart Poettering
   6
   7   systemd is free software; you can redistribute it and/or modify it
   8   under the terms of the GNU Lesser General Public License as published by
   9   the Free Software Foundation; either version 2.1 of the License, or
  10   (at your option) any later version.
  11
  12   systemd is distributed in the hope that it will be useful, but
  13   WITHOUT ANY WARRANTY; without even the implied warranty of
  14   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15   Lesser General Public License for more details.
  16
  17   You should have received a copy of the GNU Lesser General Public License
  18   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  19 ***/
  20
  21 #include <unistd.h>
  22
  23 #include "sd-daemon.h"
  24 #include "sd-messages.h"
  25
  26 #include "format-util.h"
  27 #include "journal-authenticate.h"
  28 #include "journald-kmsg.h"
  29 #include "journald-server.h"
  30 #include "journald-syslog.h"
  31 #include "process-util.h"
  32 #include "sigbus.h"
  33
  34 int main(int argc, char *argv[]) {
  35         Server server;
  36         int r;
  37
  38         if (argc > 1) {
  39                 log_error("This program does not take arguments.");
  40                 return EXIT_FAILURE;
  41         }
  42
  43         log_set_target(LOG_TARGET_SAFE);
  44         log_set_facility(LOG_SYSLOG);
  45         log_parse_environment();
  46         log_open();
  47
  48         umask(0022);
  49
  50         sigbus_install();
  51
  52         r = server_init(&server);
  53         if (r < 0)
  54                 goto finish;
  55
  56         server_vacuum(&server, false);
  57         server_flush_to_var(&server, true);
  58         server_flush_dev_kmsg(&server);
  59
  60         log_debug("systemd-journald running as pid "PID_FMT, getpid_cached());
  61         server_driver_message(&server, 0,
  62                               "MESSAGE_ID=" SD_MESSAGE_JOURNAL_START_STR,
  63                               LOG_MESSAGE("Journal started"),
  64                               NULL);
  65
  66         /* Make sure to send the usage message *after* flushing the
  67          * journal so entries from the runtime journals are ordered
  68          * before this message. See #4190 for some details. */
  69         server_space_usage_message(&server, NULL);
  70
  71         for (;;) {
  72                 usec_t t = USEC_INFINITY, n;
  73
  74                 r = sd_event_get_state(server.event);
  75                 if (r < 0)
  76                         goto finish;
  77                 if (r == SD_EVENT_FINISHED)
  78                         break;
  79
  80                 n = now(CLOCK_REALTIME);
  81
  82                 if (server.max_retention_usec > 0 && server.oldest_file_usec > 0) {
  83
  84                         /* The retention time is reached, so let's vacuum! */
  85                         if (server.oldest_file_usec + server.max_retention_usec < n) {
  86                                 log_info("Retention time reached.");
  87                                 server_rotate(&server);
  88                                 server_vacuum(&server, false);
  89                                 continue;
  90                         }
  91
  92                         /* Calculate when to rotate the next time */
  93                         t = server.oldest_file_usec + server.max_retention_usec - n;
  94                 }
  95
  96 #if HAVE_GCRYPT
  97                 if (server.system_journal) {
  98                         usec_t u;
  99
 100                         if (journal_file_next_evolve_usec(server.system_journal, &u)) {
 101                                 if (n >= u)
 102                                         t = 0;
 103                                 else
 104                                         t = MIN(t, u - n);
 105                         }
 106                 }
 107 #endif
 108
 109                 r = sd_event_run(server.event, t);
 110                 if (r < 0) {
 111                         log_error_errno(r, "Failed to run event loop: %m");
 112                         goto finish;
 113                 }
 114
 115                 server_maybe_append_tags(&server);
 116                 server_maybe_warn_forward_syslog_missed(&server);
 117         }
 118
 119         log_debug("systemd-journald stopped as pid "PID_FMT, getpid_cached());
 120         server_driver_message(&server, 0,
 121                               "MESSAGE_ID=" SD_MESSAGE_JOURNAL_STOP_STR,
 122                               LOG_MESSAGE("Journal stopped"),
 123                               NULL);
 124
 125 finish:
 126         server_done(&server);
 127
 128         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 129 }