2 This file is part of systemd.
4 Copyright 2010 Lennart Poettering
6 systemd is free software; you can redistribute it and/or modify it
7 under the terms of the GNU Lesser General Public License as published by
8 the Free Software Foundation; either version 2.1 of the License, or
9 (at your option) any later version.
11 systemd is distributed in the hope that it will be useful, but
12 WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public License
17 along with systemd; If not, see <http://www.gnu.org/licenses/>.
28 #include <sys/signalfd.h>
29 #include <sys/socket.h>
36 #include "sd-messages.h"
38 #include "alloc-util.h"
40 #include "format-util.h"
45 #include "parse-util.h"
46 #include "proc-cmdline.h"
47 #include "process-util.h"
48 #include "signal-util.h"
49 #include "socket-util.h"
50 #include "stdio-util.h"
51 #include "string-table.h"
52 #include "string-util.h"
53 #include "syslog-util.h"
54 #include "terminal-util.h"
55 #include "time-util.h"
58 #define SNDBUF_SIZE (8*1024*1024)
60 static LogTarget log_target = LOG_TARGET_CONSOLE;
61 static int log_max_level = LOG_INFO;
62 static int log_facility = LOG_DAEMON;
64 static int console_fd = STDERR_FILENO;
65 static int syslog_fd = -1;
66 static int kmsg_fd = -1;
67 static int journal_fd = -1;
69 static bool syslog_is_stream = false;
71 static bool show_color = false;
72 static bool show_location = false;
74 #if 0 /// UNNEEDED by elogind
75 static bool upgrade_syslog_to_journal = false;
78 /* Akin to glibc's __abort_msg; which is private and we hence cannot
80 static char *log_abort_msg = NULL;
82 void log_close_console(void) {
89 safe_close(console_fd);
95 static int log_open_console(void) {
101 console_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC);
105 console_fd = STDERR_FILENO;
110 void log_close_kmsg(void) {
111 kmsg_fd = safe_close(kmsg_fd);
114 static int log_open_kmsg(void) {
119 kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC);
126 void log_close_syslog(void) {
127 syslog_fd = safe_close(syslog_fd);
130 static int create_log_socket(int type) {
134 fd = socket(AF_UNIX, type|SOCK_CLOEXEC, 0);
138 (void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
140 /* We need a blocking fd here since we'd otherwise lose
141 messages way too early. However, let's not hang forever in the
142 unlikely case of a deadlock. */
144 timeval_store(&tv, 10 * USEC_PER_MSEC);
146 timeval_store(&tv, 10 * USEC_PER_SEC);
147 (void) setsockopt(fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv));
152 static int log_open_syslog(void) {
154 static const union sockaddr_union sa = {
155 .un.sun_family = AF_UNIX,
156 .un.sun_path = "/dev/log",
164 syslog_fd = create_log_socket(SOCK_DGRAM);
170 if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
171 safe_close(syslog_fd);
173 /* Some legacy syslog systems still use stream
174 * sockets. They really shouldn't. But what can we
176 syslog_fd = create_log_socket(SOCK_STREAM);
182 if (connect(syslog_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
187 syslog_is_stream = true;
189 syslog_is_stream = false;
198 void log_close_journal(void) {
199 #if 0 /// elogind does not support journald
200 journal_fd = safe_close(journal_fd);
204 #if 0 /// UNNEEDED by elogind
205 static int log_open_journal(void) {
207 static const union sockaddr_union sa = {
208 .un.sun_family = AF_UNIX,
209 .un.sun_path = "/run/systemd/journal/socket",
217 journal_fd = create_log_socket(SOCK_DGRAM);
218 if (journal_fd < 0) {
223 if (connect(journal_fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0) {
239 /* If we don't use the console we close it here, to not get
240 * killed by SAK. If we don't use syslog we close it here so
241 * that we are not confused by somebody deleting the socket in
242 * the fs. If we don't use /dev/kmsg we still keep it open,
243 * because there is no reason to close it. */
245 if (log_target == LOG_TARGET_NULL) {
252 if ((log_target != LOG_TARGET_AUTO && log_target != LOG_TARGET_SAFE) ||
254 isatty(STDERR_FILENO) <= 0) {
256 #if 0 /// elogind does not support logging to systemd-journald
257 if (log_target == LOG_TARGET_AUTO ||
258 log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
259 log_target == LOG_TARGET_JOURNAL) {
260 r = log_open_journal();
269 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
270 log_target == LOG_TARGET_SYSLOG) {
271 r = log_open_syslog();
279 if (log_target == LOG_TARGET_AUTO ||
280 log_target == LOG_TARGET_SAFE ||
281 log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
282 log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
283 log_target == LOG_TARGET_KMSG) {
297 return log_open_console();
300 void log_set_target(LogTarget target) {
302 assert(target < _LOG_TARGET_MAX);
304 #if 0 /// elogind does not support logging to systemd-journald
305 if (upgrade_syslog_to_journal) {
306 if (target == LOG_TARGET_SYSLOG)
307 target = LOG_TARGET_JOURNAL;
308 else if (target == LOG_TARGET_SYSLOG_OR_KMSG)
309 target = LOG_TARGET_JOURNAL_OR_KMSG;
316 void log_close(void) {
323 #if 0 /// UNNEEDED by elogind
324 void log_forget_fds(void) {
325 console_fd = kmsg_fd = syslog_fd = journal_fd = -1;
329 void log_set_max_level(int level) {
330 assert((level & LOG_PRIMASK) == level);
332 log_max_level = level;
335 void log_set_facility(int facility) {
336 log_facility = facility;
339 static int write_to_console(
345 const char *buffer) {
347 char location[256], prefix[1 + DECIMAL_STR_MAX(int) + 2];
348 struct iovec iovec[6] = {};
355 if (log_target == LOG_TARGET_CONSOLE_PREFIXED) {
356 xsprintf(prefix, "<%i>", level);
357 IOVEC_SET_STRING(iovec[n++], prefix);
360 highlight = LOG_PRI(level) <= LOG_ERR && show_color;
363 snprintf(location, sizeof(location), "(%s:%i) ", file, line);
364 IOVEC_SET_STRING(iovec[n++], location);
368 IOVEC_SET_STRING(iovec[n++], ANSI_HIGHLIGHT_RED);
369 IOVEC_SET_STRING(iovec[n++], buffer);
371 IOVEC_SET_STRING(iovec[n++], ANSI_NORMAL);
372 IOVEC_SET_STRING(iovec[n++], "\n");
374 if (writev(console_fd, iovec, n) < 0) {
376 if (errno == EIO && getpid() == 1) {
378 /* If somebody tried to kick us from our
379 * console tty (via vhangup() or suchlike),
380 * try to reconnect */
388 if (writev(console_fd, iovec, n) < 0)
397 static int write_to_syslog(
403 const char *buffer) {
405 char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
407 header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
408 struct iovec iovec[5] = {};
409 struct msghdr msghdr = {
411 .msg_iovlen = ELEMENTSOF(iovec),
419 xsprintf(header_priority, "<%i>", level);
421 t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC);
426 if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
429 xsprintf(header_pid, "["PID_FMT"]: ", getpid());
431 IOVEC_SET_STRING(iovec[0], header_priority);
432 IOVEC_SET_STRING(iovec[1], header_time);
433 IOVEC_SET_STRING(iovec[2], program_invocation_short_name);
434 IOVEC_SET_STRING(iovec[3], header_pid);
435 IOVEC_SET_STRING(iovec[4], buffer);
437 /* When using syslog via SOCK_STREAM separate the messages by NUL chars */
438 if (syslog_is_stream)
444 n = sendmsg(syslog_fd, &msghdr, MSG_NOSIGNAL);
448 if (!syslog_is_stream ||
449 (size_t) n >= IOVEC_TOTAL_SIZE(iovec, ELEMENTSOF(iovec)))
452 IOVEC_INCREMENT(iovec, ELEMENTSOF(iovec), n);
458 static int write_to_kmsg(
464 const char *buffer) {
466 char header_priority[2 + DECIMAL_STR_MAX(int) + 1],
467 header_pid[4 + DECIMAL_STR_MAX(pid_t) + 1];
468 struct iovec iovec[5] = {};
473 xsprintf(header_priority, "<%i>", level);
474 xsprintf(header_pid, "["PID_FMT"]: ", getpid());
476 IOVEC_SET_STRING(iovec[0], header_priority);
477 IOVEC_SET_STRING(iovec[1], program_invocation_short_name);
478 IOVEC_SET_STRING(iovec[2], header_pid);
479 IOVEC_SET_STRING(iovec[3], buffer);
480 IOVEC_SET_STRING(iovec[4], "\n");
482 if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
488 #if 0 /// UNNEEDED by elogind
489 static int log_do_header(
494 const char *file, int line, const char *func,
495 const char *object_field, const char *object,
496 const char *extra_field, const char *extra) {
498 snprintf(header, size,
500 "SYSLOG_FACILITY=%i\n"
507 "SYSLOG_IDENTIFIER=%s\n",
510 isempty(file) ? "" : "CODE_FILE=",
511 isempty(file) ? "" : file,
512 isempty(file) ? "" : "\n",
513 line ? "CODE_LINE=" : "",
514 line ? 1 : 0, line, /* %.0d means no output too, special case for 0 */
516 isempty(func) ? "" : "CODE_FUNCTION=",
517 isempty(func) ? "" : func,
518 isempty(func) ? "" : "\n",
519 error ? "ERRNO=" : "",
520 error ? 1 : 0, error,
522 isempty(object) ? "" : object_field,
523 isempty(object) ? "" : object,
524 isempty(object) ? "" : "\n",
525 isempty(extra) ? "" : extra_field,
526 isempty(extra) ? "" : extra,
527 isempty(extra) ? "" : "\n",
528 program_invocation_short_name);
533 static int write_to_journal(
539 const char *object_field,
541 const char *extra_field,
543 const char *buffer) {
545 char header[LINE_MAX];
546 struct iovec iovec[4] = {};
547 struct msghdr mh = {};
552 log_do_header(header, sizeof(header), level, error, file, line, func, object_field, object, extra_field, extra);
554 IOVEC_SET_STRING(iovec[0], header);
555 IOVEC_SET_STRING(iovec[1], "MESSAGE=");
556 IOVEC_SET_STRING(iovec[2], buffer);
557 IOVEC_SET_STRING(iovec[3], "\n");
560 mh.msg_iovlen = ELEMENTSOF(iovec);
562 if (sendmsg(journal_fd, &mh, MSG_NOSIGNAL) < 0)
569 static int log_dispatch(
575 const char *object_field,
578 const char *extra_field,
586 if (log_target == LOG_TARGET_NULL)
589 /* Patch in LOG_DAEMON facility if necessary */
590 if ((level & LOG_FACMASK) == 0)
591 level = log_facility | LOG_PRI(level);
597 buffer += strspn(buffer, NEWLINE);
602 if ((e = strpbrk(buffer, NEWLINE)))
605 #if 0 /// elogind does not support logging to systemd-journald
606 if (log_target == LOG_TARGET_AUTO ||
607 log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
608 log_target == LOG_TARGET_JOURNAL) {
610 k = write_to_journal(level, error, file, line, func, object_field, object, extra_field, extra, buffer);
619 if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
620 log_target == LOG_TARGET_SYSLOG) {
622 k = write_to_syslog(level, error, file, line, func, buffer);
631 (log_target == LOG_TARGET_AUTO ||
632 log_target == LOG_TARGET_SAFE ||
633 log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
634 log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
635 log_target == LOG_TARGET_KMSG)) {
637 k = write_to_kmsg(level, error, file, line, func, buffer);
645 (void) write_to_console(level, error, file, line, func, buffer);
653 int log_dump_internal(
663 /* This modifies the buffer... */
668 if (_likely_(LOG_PRI(level) > log_max_level))
671 return log_dispatch(level, error, file, line, func, NULL, NULL, NULL, NULL, buffer);
684 char buffer[LINE_MAX];
689 if (_likely_(LOG_PRI(level) > log_max_level))
692 /* Make sure that %m maps to the specified error */
696 vsnprintf(buffer, sizeof(buffer), format, ap);
698 return log_dispatch(level, error, file, line, func, NULL, NULL, NULL, NULL, buffer);
707 const char *format, ...) {
712 va_start(ap, format);
713 r = log_internalv(level, error, file, line, func, format, ap);
719 int log_object_internalv(
725 const char *object_field,
727 const char *extra_field,
739 if (_likely_(LOG_PRI(level) > log_max_level))
742 /* Make sure that %m maps to the specified error */
746 /* Prepend the object name before the message */
751 l = n + 2 + LINE_MAX;
753 buffer = newa(char, l);
754 b = stpcpy(stpcpy(buffer, object), ": ");
757 b = buffer = newa(char, l);
760 vsnprintf(b, l, format, ap);
762 return log_dispatch(level, error, file, line, func, object_field, object, extra_field, extra, buffer);
765 int log_object_internal(
771 const char *object_field,
773 const char *extra_field,
775 const char *format, ...) {
780 va_start(ap, format);
781 r = log_object_internalv(level, error, file, line, func, object_field, object, extra_field, extra, format, ap);
787 static void log_assert(
793 const char *format) {
795 static char buffer[LINE_MAX];
797 if (_likely_(LOG_PRI(level) > log_max_level))
800 DISABLE_WARNING_FORMAT_NONLITERAL;
801 snprintf(buffer, sizeof buffer, format, text, file, line, func);
804 log_abort_msg = buffer;
806 log_dispatch(level, 0, file, line, func, NULL, NULL, NULL, NULL, buffer);
809 noreturn void log_assert_failed(const char *text, const char *file, int line, const char *func) {
810 log_assert(LOG_CRIT, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Aborting.");
814 noreturn void log_assert_failed_unreachable(const char *text, const char *file, int line, const char *func) {
815 log_assert(LOG_CRIT, text, file, line, func, "Code should not be reached '%s' at %s:%u, function %s(). Aborting.");
819 void log_assert_failed_return(const char *text, const char *file, int line, const char *func) {
821 log_assert(LOG_DEBUG, text, file, line, func, "Assertion '%s' failed at %s:%u, function %s(). Ignoring.");
824 int log_oom_internal(const char *file, int line, const char *func) {
825 log_internal(LOG_ERR, ENOMEM, file, line, func, "Out of memory.");
829 int log_format_iovec(
833 bool newline_separator,
838 static const char nl = '\n';
840 while (format && *n + 1 < iovec_len) {
845 /* We need to copy the va_list structure,
846 * since vasprintf() leaves it afterwards at
847 * an undefined location */
853 r = vasprintf(&m, format, aq);
858 /* Now, jump enough ahead, so that we point to
859 * the next format string */
860 VA_FORMAT_ADVANCE(format, ap);
862 IOVEC_SET_STRING(iovec[(*n)++], m);
864 if (newline_separator) {
865 iovec[*n].iov_base = (char*) &nl;
866 iovec[*n].iov_len = 1;
870 format = va_arg(ap, char *);
875 int log_struct_internal(
881 const char *format, ...) {
891 if (_likely_(LOG_PRI(level) > log_max_level))
894 if (log_target == LOG_TARGET_NULL)
897 if ((level & LOG_FACMASK) == 0)
898 level = log_facility | LOG_PRI(level);
900 #if 0 /// elogind does not support logging to systemd-journald
901 if ((log_target == LOG_TARGET_AUTO ||
902 log_target == LOG_TARGET_JOURNAL_OR_KMSG ||
903 log_target == LOG_TARGET_JOURNAL) &&
905 char header[LINE_MAX];
906 struct iovec iovec[17] = {};
912 bool fallback = false;
914 /* If the journal is available do structured logging */
915 log_do_header(header, sizeof(header), level, error, file, line, func, NULL, NULL, NULL, NULL);
916 IOVEC_SET_STRING(iovec[n++], header);
918 va_start(ap, format);
919 r = log_format_iovec(iovec, ELEMENTSOF(iovec), &n, true, error, format, ap);
924 (void) sendmsg(journal_fd, &mh, MSG_NOSIGNAL);
928 for (i = 1; i < n; i += 2)
929 free(iovec[i].iov_base);
936 /* Fallback if journal logging is not available or didn't work. */
938 va_start(ap, format);
946 vsnprintf(buf, sizeof(buf), format, aq);
949 if (startswith(buf, "MESSAGE=")) {
954 VA_FORMAT_ADVANCE(format, ap);
956 format = va_arg(ap, char *);
963 return log_dispatch(level, error, file, line, func, NULL, NULL, NULL, NULL, buf + 8);
966 int log_set_target_from_string(const char *e) {
969 t = log_target_from_string(e);
977 int log_set_max_level_from_string(const char *e) {
980 t = log_level_from_string(e);
984 log_set_max_level(t);
988 static int parse_proc_cmdline_item(const char *key, const char *value, void *data) {
991 * The systemd.log_xyz= settings are parsed by all tools, and
994 * However, "quiet" is only parsed by PID 1, and only turns of
995 * status output to /dev/console, but does not alter the log
999 if (streq(key, "debug") && !value)
1000 log_set_max_level(LOG_DEBUG);
1002 else if (streq(key, "systemd.log_target") && value) {
1004 if (log_set_target_from_string(value) < 0)
1005 log_warning("Failed to parse log target '%s'. Ignoring.", value);
1007 } else if (streq(key, "systemd.log_level") && value) {
1009 if (log_set_max_level_from_string(value) < 0)
1010 log_warning("Failed to parse log level '%s'. Ignoring.", value);
1012 } else if (streq(key, "systemd.log_color") && value) {
1014 if (log_show_color_from_string(value) < 0)
1015 log_warning("Failed to parse log color setting '%s'. Ignoring.", value);
1017 } else if (streq(key, "systemd.log_location") && value) {
1019 if (log_show_location_from_string(value) < 0)
1020 log_warning("Failed to parse log location setting '%s'. Ignoring.", value);
1026 void log_parse_environment(void) {
1029 if (get_ctty_devnr(0, NULL) < 0)
1030 /* Only try to read the command line in daemons.
1031 We assume that anything that has a controlling
1032 tty is user stuff. */
1033 (void) parse_proc_cmdline(parse_proc_cmdline_item, NULL, true);
1035 e = secure_getenv("SYSTEMD_LOG_TARGET");
1036 if (e && log_set_target_from_string(e) < 0)
1037 log_warning("Failed to parse log target '%s'. Ignoring.", e);
1039 e = secure_getenv("SYSTEMD_LOG_LEVEL");
1040 if (e && log_set_max_level_from_string(e) < 0)
1041 log_warning("Failed to parse log level '%s'. Ignoring.", e);
1043 e = secure_getenv("SYSTEMD_LOG_COLOR");
1044 if (e && log_show_color_from_string(e) < 0)
1045 log_warning("Failed to parse bool '%s'. Ignoring.", e);
1047 e = secure_getenv("SYSTEMD_LOG_LOCATION");
1048 if (e && log_show_location_from_string(e) < 0)
1049 log_warning("Failed to parse bool '%s'. Ignoring.", e);
1052 LogTarget log_get_target(void) {
1056 int log_get_max_level(void) {
1057 return log_max_level;
1060 void log_show_color(bool b) {
1064 bool log_get_show_color(void) {
1068 void log_show_location(bool b) {
1072 bool log_get_show_location(void) {
1073 return show_location;
1076 int log_show_color_from_string(const char *e) {
1079 t = parse_boolean(e);
1087 int log_show_location_from_string(const char *e) {
1090 t = parse_boolean(e);
1094 log_show_location(t);
1098 bool log_on_console(void) {
1099 if (log_target == LOG_TARGET_CONSOLE ||
1100 log_target == LOG_TARGET_CONSOLE_PREFIXED)
1103 return syslog_fd < 0 && kmsg_fd < 0 && journal_fd < 0;
1106 static const char *const log_target_table[_LOG_TARGET_MAX] = {
1107 [LOG_TARGET_CONSOLE] = "console",
1108 [LOG_TARGET_CONSOLE_PREFIXED] = "console-prefixed",
1109 [LOG_TARGET_KMSG] = "kmsg",
1110 #if 0 /// elogind does not support logging to systemd-journald
1111 [LOG_TARGET_JOURNAL] = "journal",
1112 [LOG_TARGET_JOURNAL_OR_KMSG] = "journal-or-kmsg",
1114 [LOG_TARGET_SYSLOG] = "syslog",
1115 [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg",
1116 [LOG_TARGET_AUTO] = "auto",
1117 [LOG_TARGET_SAFE] = "safe",
1118 [LOG_TARGET_NULL] = "null"
1121 DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget);
1123 #if 0 /// UNNEEDED by elogind
1124 void log_received_signal(int level, const struct signalfd_siginfo *si) {
1125 if (si->ssi_pid > 0) {
1126 _cleanup_free_ char *p = NULL;
1128 get_process_comm(si->ssi_pid, &p);
1131 "Received SIG%s from PID %"PRIu32" (%s).",
1132 signal_to_string(si->ssi_signo),
1133 si->ssi_pid, strna(p));
1137 signal_to_string(si->ssi_signo));
1141 void log_set_upgrade_syslog_to_journal(bool b) {
1142 upgrade_syslog_to_journal = b;
1146 int log_syntax_internal(
1149 const char *config_file,
1150 unsigned config_line,
1155 const char *format, ...) {
1158 char buffer[LINE_MAX];
1160 const char *unit_fmt = NULL;
1165 if (_likely_(LOG_PRI(level) > log_max_level))
1168 if (log_target == LOG_TARGET_NULL)
1174 va_start(ap, format);
1175 vsnprintf(buffer, sizeof(buffer), format, ap);
1179 unit_fmt = getpid() == 1 ? "UNIT=%s" : "USER_UNIT=%s";
1181 return log_struct_internal(
1184 LOG_MESSAGE_ID(SD_MESSAGE_INVALID_CONFIGURATION),
1185 "CONFIG_FILE=%s", config_file,
1186 "CONFIG_LINE=%u", config_line,
1187 LOG_MESSAGE("%s:%u: %s", config_file, config_line, buffer),