src/journal/journald-console.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 Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 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   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <time.h>
  23 #include <fcntl.h>
  24 #include <sys/socket.h>
  25
  26 #include "alloc-util.h"
  27 #include "fd-util.h"
  28 #include "fileio.h"
  29 #include "formats-util.h"
  30 #include "io-util.h"
  31 #include "journald-console.h"
  32 #include "journald-server.h"
  33 #include "parse-util.h"
  34 #include "process-util.h"
  35 #include "stdio-util.h"
  36 #include "terminal-util.h"
  37
  38 static bool prefix_timestamp(void) {
  39
  40         static int cached_printk_time = -1;
  41
  42         if (_unlikely_(cached_printk_time < 0)) {
  43                 _cleanup_free_ char *p = NULL;
  44
  45                 cached_printk_time =
  46                         read_one_line_file("/sys/module/printk/parameters/time", &p) >= 0
  47                         && parse_boolean(p) > 0;
  48         }
  49
  50         return cached_printk_time;
  51 }
  52
  53 void server_forward_console(
  54                 Server *s,
  55                 int priority,
  56                 const char *identifier,
  57                 const char *message,
  58                 const struct ucred *ucred) {
  59
  60         struct iovec iovec[5];
  61         struct timespec ts;
  62         char tbuf[sizeof("[] ")-1 + DECIMAL_STR_MAX(ts.tv_sec) + DECIMAL_STR_MAX(ts.tv_nsec)-3 + 1];
  63         char header_pid[sizeof("[]: ")-1 + DECIMAL_STR_MAX(pid_t)];
  64         int n = 0, fd;
  65         _cleanup_free_ char *ident_buf = NULL;
  66         const char *tty;
  67
  68         assert(s);
  69         assert(message);
  70
  71         if (LOG_PRI(priority) > s->max_level_console)
  72                 return;
  73
  74         /* First: timestamp */
  75         if (prefix_timestamp()) {
  76                 assert_se(clock_gettime(CLOCK_MONOTONIC, &ts) == 0);
  77                 xsprintf(tbuf, "[%5"PRI_TIME".%06ld] ",
  78                          ts.tv_sec,
  79                          ts.tv_nsec / 1000);
  80                 IOVEC_SET_STRING(iovec[n++], tbuf);
  81         }
  82
  83         /* Second: identifier and PID */
  84         if (ucred) {
  85                 if (!identifier) {
  86                         get_process_comm(ucred->pid, &ident_buf);
  87                         identifier = ident_buf;
  88                 }
  89
  90                 xsprintf(header_pid, "["PID_FMT"]: ", ucred->pid);
  91
  92                 if (identifier)
  93                         IOVEC_SET_STRING(iovec[n++], identifier);
  94
  95                 IOVEC_SET_STRING(iovec[n++], header_pid);
  96         } else if (identifier) {
  97                 IOVEC_SET_STRING(iovec[n++], identifier);
  98                 IOVEC_SET_STRING(iovec[n++], ": ");
  99         }
 100
 101         /* Fourth: message */
 102         IOVEC_SET_STRING(iovec[n++], message);
 103         IOVEC_SET_STRING(iovec[n++], "\n");
 104
 105         tty = s->tty_path ? s->tty_path : "/dev/console";
 106
 107         fd = open_terminal(tty, O_WRONLY|O_NOCTTY|O_CLOEXEC);
 108         if (fd < 0) {
 109                 log_debug_errno(fd, "Failed to open %s for logging: %m", tty);
 110                 return;
 111         }
 112
 113         if (writev(fd, iovec, n) < 0)
 114                 log_debug_errno(errno, "Failed to write to %s for logging: %m", tty);
 115
 116         safe_close(fd);
 117 }