1 /*-*- Mode: C; c-basic-offset: 8 -*-*/
4 This file is part of systemd.
6 Copyright 2010 Lennart Poettering
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.
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.
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/>.
22 #include <sys/socket.h>
23 #include <sys/types.h>
31 #include <sys/epoll.h>
38 #include "sd-daemon.h"
40 #define STREAM_BUFFER 2048
41 #define STREAMS_MAX 256
42 #define SERVER_FD_MAX 16
43 #define TIMEOUT ((int) (10*MSEC_PER_SEC))
45 typedef struct Stream Stream;
47 typedef struct Server {
54 LIST_HEAD(Stream, streams);
58 typedef enum StreamTarget {
63 typedef enum StreamState {
86 char buffer[STREAM_BUFFER];
89 LIST_FIELDS(Stream, stream);
92 static int stream_log(Stream *s, char *p, usec_t timestamp) {
94 char header_priority[16], header_time[64], header_pid[16];
95 struct iovec iovec[5];
101 priority = s->priority;
105 p[1] >= '0' && p[1] <= '7' &&
108 /* Detected priority prefix */
109 priority = LOG_MAKEPRI(LOG_FAC(priority), (p[1] - '0'));
118 * The format glibc uses to talk to the syslog daemon is:
120 * <priority>time process[pid]: msg
122 * The format the kernel uses is:
126 * We extend the latter to include the process name and pid.
129 snprintf(header_priority, sizeof(header_priority), "<%i>",
130 s->target == STREAM_SYSLOG ? priority : LOG_PRI(priority));
131 char_array_0(header_priority);
133 if (s->target == STREAM_SYSLOG) {
137 t = (time_t) (timestamp / USEC_PER_SEC);
138 if (!(tm = localtime(&t)))
141 if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
145 snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) s->pid);
146 char_array_0(header_pid);
149 IOVEC_SET_STRING(iovec[0], header_priority);
151 if (s->target == STREAM_SYSLOG) {
152 struct msghdr msghdr;
154 IOVEC_SET_STRING(iovec[1], header_time);
155 IOVEC_SET_STRING(iovec[2], s->process);
156 IOVEC_SET_STRING(iovec[3], header_pid);
157 IOVEC_SET_STRING(iovec[4], p);
160 msghdr.msg_iov = iovec;
161 msghdr.msg_iovlen = ELEMENTSOF(iovec);
163 if (sendmsg(s->server->syslog_fd, &msghdr, MSG_NOSIGNAL) < 0)
166 } else if (s->target == STREAM_KMSG) {
167 IOVEC_SET_STRING(iovec[1], s->process);
168 IOVEC_SET_STRING(iovec[2], header_pid);
169 IOVEC_SET_STRING(iovec[3], p);
170 IOVEC_SET_STRING(iovec[4], (char*) "\n");
172 if (writev(s->server->kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
175 assert_not_reached("Unknown log target");
180 static int stream_line(Stream *s, char *p, usec_t timestamp) {
191 if (streq(p, "syslog"))
192 s->target = STREAM_SYSLOG;
193 else if (streq(p, "kmsg")) {
195 if (s->server->kmsg_fd >= 0 && s->uid == 0)
196 s->target = STREAM_KMSG;
198 log_warning("/dev/kmsg logging not available.");
202 log_warning("Failed to parse log target line.");
205 s->state = STREAM_PRIORITY;
208 case STREAM_PRIORITY:
209 if ((r = safe_atoi(p, &s->priority)) < 0) {
210 log_warning("Failed to parse log priority line: %s", strerror(errno));
214 if (s->priority < 0) {
215 log_warning("Log priority negative: %s", strerror(errno));
219 s->state = STREAM_PROCESS;
223 if (!(s->process = strdup(p)))
226 s->state = STREAM_PREFIX;
231 if ((r = parse_boolean(p)) < 0)
235 s->state = STREAM_RUNNING;
239 return stream_log(s, p, timestamp);
242 assert_not_reached("Unknown stream state");
245 static int stream_scan(Stream *s, usec_t timestamp) {
253 remaining = s->length;
257 if (!(newline = memchr(p, '\n', remaining)))
262 if ((r = stream_line(s, p, timestamp)) >= 0) {
263 remaining -= newline-p+1;
269 memmove(s->buffer, p, remaining);
270 s->length = remaining;
276 static int stream_process(Stream *s, usec_t timestamp) {
281 if ((l = read(s->fd, s->buffer+s->length, STREAM_BUFFER-s->length)) < 0) {
286 log_warning("Failed to read from stream: %s", strerror(errno));
295 r = stream_scan(s, timestamp);
303 static void stream_free(Stream *s) {
307 assert(s->server->n_streams > 0);
308 s->server->n_streams--;
309 LIST_REMOVE(Stream, stream, s->server->streams, s);
315 epoll_ctl(s->server->epoll_fd, EPOLL_CTL_DEL, s->fd, NULL);
317 close_nointr_nofail(s->fd);
324 static int stream_new(Server *s, int server_fd) {
328 socklen_t len = sizeof(ucred);
329 struct epoll_event ev;
334 if ((fd = accept4(server_fd, NULL, NULL, SOCK_NONBLOCK|SOCK_CLOEXEC)) < 0)
337 if (s->n_streams >= STREAMS_MAX) {
338 log_warning("Too many connections, refusing connection.");
339 close_nointr_nofail(fd);
343 if (!(stream = new0(Stream, 1))) {
344 close_nointr_nofail(fd);
350 if (getsockopt(stream->fd, SOL_SOCKET, SO_PEERCRED, &ucred, &len) < 0) {
355 if (shutdown(fd, SHUT_WR) < 0) {
361 ev.data.ptr = stream;
363 if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {
368 stream->pid = ucred.pid;
369 stream->uid = ucred.uid;
372 LIST_PREPEND(Stream, stream, s->streams, stream);
382 static void server_done(Server *s) {
387 stream_free(s->streams);
389 for (i = 0; i < s->n_server_fd; i++)
390 close_nointr_nofail(SD_LISTEN_FDS_START+i);
392 if (s->syslog_fd >= 0)
393 close_nointr_nofail(s->syslog_fd);
395 if (s->epoll_fd >= 0)
396 close_nointr_nofail(s->epoll_fd);
399 close_nointr_nofail(s->kmsg_fd);
402 static int server_init(Server *s, unsigned n_sockets) {
407 struct sockaddr_un un;
411 assert(n_sockets > 0);
415 s->n_server_fd = n_sockets;
419 if ((s->epoll_fd = epoll_create1(EPOLL_CLOEXEC)) < 0) {
421 log_error("Failed to create epoll object: %s", strerror(errno));
425 for (i = 0; i < n_sockets; i++) {
426 struct epoll_event ev;
429 fd = SD_LISTEN_FDS_START+i;
431 if ((r = sd_is_socket(fd, AF_UNSPEC, SOCK_STREAM, 1)) < 0) {
432 log_error("Failed to determine file descriptor type: %s", strerror(-r));
437 log_error("Wrong file descriptor type.");
444 ev.data.ptr = UINT_TO_PTR(fd);
445 if (epoll_ctl(s->epoll_fd, EPOLL_CTL_ADD, fd, &ev) < 0) {
447 log_error("Failed to add server fd to epoll object: %s", strerror(errno));
452 if ((s->syslog_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) {
454 log_error("Failed to create log fd: %s", strerror(errno));
459 sa.un.sun_family = AF_UNIX;
460 strncpy(sa.un.sun_path, "/dev/log", sizeof(sa.un.sun_path));
462 if (connect(s->syslog_fd, &sa.sa, sizeof(sa)) < 0) {
464 log_error("Failed to connect log socket to /dev/log: %s", strerror(errno));
468 /* /dev/kmsg logging is strictly optional */
469 if ((s->kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0)
470 log_debug("Failed to open /dev/kmsg for logging, disabling kernel log buffer support: %s", strerror(errno));
479 static int process_event(Server *s, struct epoll_event *ev) {
484 /* Yes, this is a bit ugly, we assume that that valid pointers
485 * are > SD_LISTEN_FDS_START+SERVER_FD_MAX. Which is certainly
486 * true on Linux (and probably most other OSes, too, since the
487 * first 4k usually are part of a seperate null pointer
488 * dereference page. */
490 if (PTR_TO_UINT(ev->data.ptr) >= SD_LISTEN_FDS_START &&
491 PTR_TO_UINT(ev->data.ptr) < SD_LISTEN_FDS_START+s->n_server_fd) {
493 if (ev->events != EPOLLIN) {
494 log_info("Got invalid event from epoll. (1)");
498 if ((r = stream_new(s, PTR_TO_UINT(ev->data.ptr))) < 0) {
499 log_info("Failed to accept new connection: %s", strerror(-r));
505 Stream *stream = ev->data.ptr;
507 timestamp = now(CLOCK_REALTIME);
509 if (!(ev->events & EPOLLIN)) {
510 log_info("Got invalid event from epoll. (2)");
515 if ((r = stream_process(stream, timestamp)) <= 0) {
518 log_info("Got error on stream: %s", strerror(-r));
528 int main(int argc, char *argv[]) {
532 log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
533 log_parse_environment();
535 log_info("systemd-logger running as pid %llu", (unsigned long long) getpid());
537 if ((n = sd_listen_fds(true)) < 0) {
538 log_error("Failed to read listening file descriptors from environment: %s", strerror(-r));
542 if (n <= 0 || n > SERVER_FD_MAX) {
543 log_error("No or too many file descriptors passed.");
547 if (server_init(&server, (unsigned) n) < 0)
551 struct epoll_event event;
554 if ((k = epoll_wait(server.epoll_fd,
556 server.n_streams <= 0 ? TIMEOUT : -1)) < 0) {
561 log_error("epoll_wait() failed: %s", strerror(errno));
568 if ((k = process_event(&server, &event)) < 0)
574 server_done(&server);
576 log_info("systemd-logger stopped as pid %llu", (unsigned long long) getpid());