1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
4 This file is part of systemd.
6 Copyright 2011 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>
29 #include "sd-journal.h"
31 #include "socket-util.h"
33 #define SNDBUF_SIZE (8*1024*1024)
35 /* We open a single fd, and we'll share it with the current process,
36 * all its threads, and all its subprocesses. This means we need to
37 * initialize it atomically, and need to operate on it atomically
38 * never assuming we are the only user */
40 static int journal_fd(void) {
42 static int fd_plus_one = 0;
46 return fd_plus_one - 1;
48 fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0);
52 fd_inc_sndbuf(fd, SNDBUF_SIZE);
54 if (!__sync_bool_compare_and_swap(&fd_plus_one, 0, fd+1)) {
55 close_nointr_nofail(fd);
62 _public_ int sd_journal_print(int priority, const char *format, ...) {
67 r = sd_journal_printv(priority, format, ap);
73 _public_ int sd_journal_printv(int priority, const char *format, va_list ap) {
74 char buffer[8 + LINE_MAX], p[11];
77 if (priority < 0 || priority > 7)
83 snprintf(p, sizeof(p), "PRIORITY=%i", priority & LOG_PRIMASK);
86 memcpy(buffer, "MESSAGE=", 8);
87 vsnprintf(buffer+8, sizeof(buffer) - 8, format, ap);
91 IOVEC_SET_STRING(iov[0], buffer);
92 IOVEC_SET_STRING(iov[1], p);
94 return sd_journal_sendv(iov, 2);
97 _public_ int sd_journal_send(const char *format, ...) {
98 int r, n = 0, i = 0, j;
100 struct iovec *iov = NULL;
102 va_start(ap, format);
109 c = realloc(iov, n * sizeof(struct iovec));
118 if (vasprintf(&buffer, format, ap) < 0) {
123 IOVEC_SET_STRING(iov[i++], buffer);
125 format = va_arg(ap, char *);
129 r = sd_journal_sendv(iov, i);
132 for (j = 0; j < i; j++)
133 free(iov[j].iov_base);
140 _public_ int sd_journal_sendv(const struct iovec *iov, int n) {
146 struct sockaddr_un sa;
149 struct cmsghdr cmsghdr;
150 uint8_t buf[CMSG_SPACE(sizeof(int))];
152 struct cmsghdr *cmsg;
153 /* We use /dev/shm instead of /tmp here, since we want this to
154 * be a tmpfs, and one that is available from early boot on
155 * and where unprivileged users can create files. */
156 char path[] = "/dev/shm/journal.XXXXXX";
161 w = alloca(sizeof(struct iovec) * n * 5);
162 l = alloca(sizeof(uint64_t) * n);
164 for (i = 0; i < n; i++) {
167 if (!iov[i].iov_base ||
171 c = memchr(iov[i].iov_base, '=', iov[i].iov_len);
172 if (!c || c == iov[i].iov_base)
175 nl = memchr(iov[i].iov_base, '\n', iov[i].iov_len);
180 /* Already includes a newline? Bummer, then
181 * let's write the variable name, then a
182 * newline, then the size (64bit LE), followed
183 * by the data and a final newline */
185 w[j].iov_base = iov[i].iov_base;
186 w[j].iov_len = c - (char*) iov[i].iov_base;
189 IOVEC_SET_STRING(w[j++], "\n");
191 l[i] = htole64(iov[i].iov_len - (c - (char*) iov[i].iov_base) - 1);
192 w[j].iov_base = &l[i];
193 w[j].iov_len = sizeof(uint64_t);
196 w[j].iov_base = c + 1;
197 w[j].iov_len = iov[i].iov_len - (c - (char*) iov[i].iov_base) - 1;
201 /* Nothing special? Then just add the line and
202 * append a newline */
205 IOVEC_SET_STRING(w[j++], "\n");
213 sa.sun_family = AF_UNIX;
214 strncpy(sa.sun_path, "/run/systemd/journal/socket", sizeof(sa.sun_path));
218 mh.msg_namelen = offsetof(struct sockaddr_un, sun_path) + strlen(sa.sun_path);
222 k = sendmsg(fd, &mh, MSG_NOSIGNAL);
226 if (errno != EMSGSIZE && errno != ENOBUFS)
229 /* Message doesn't fit... Let's dump the data in a temporary
230 * file and just pass a file descriptor of it to the other
233 buffer_fd = mkostemp(path, O_CLOEXEC|O_RDWR);
237 if (unlink(path) < 0) {
238 close_nointr_nofail(buffer_fd);
242 n = writev(buffer_fd, w, j);
244 close_nointr_nofail(buffer_fd);
252 mh.msg_control = &control;
253 mh.msg_controllen = sizeof(control);
255 cmsg = CMSG_FIRSTHDR(&mh);
256 cmsg->cmsg_level = SOL_SOCKET;
257 cmsg->cmsg_type = SCM_RIGHTS;
258 cmsg->cmsg_len = CMSG_LEN(sizeof(int));
259 memcpy(CMSG_DATA(cmsg), &buffer_fd, sizeof(int));
261 mh.msg_controllen = cmsg->cmsg_len;
263 k = sendmsg(fd, &mh, MSG_NOSIGNAL);
264 close_nointr_nofail(buffer_fd);
272 _public_ int sd_journal_stream_fd(const char *identifier, int priority, int level_prefix) {
273 union sockaddr_union sa;
279 if (priority < 0 || priority > 7)
282 fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0);
287 sa.un.sun_family = AF_UNIX;
288 strncpy(sa.un.sun_path, "/run/systemd/journal/stdout", sizeof(sa.un.sun_path));
290 r = connect(fd, &sa.sa, offsetof(union sockaddr_union, un.sun_path) + strlen(sa.un.sun_path));
292 close_nointr_nofail(fd);
296 if (shutdown(fd, SHUT_RD) < 0) {
297 close_nointr_nofail(fd);
301 fd_inc_sndbuf(fd, SNDBUF_SIZE);
306 l = strlen(identifier);
307 header = alloca(l + 1 + 2 + 2 + 2 + 2 + 2);
309 memcpy(header, identifier, l);
311 header[l++] = '0' + priority;
313 header[l++] = '0' + !!level_prefix;
322 r = loop_write(fd, header, l, false);
324 close_nointr_nofail(fd);
328 if ((size_t) r != l) {
329 close_nointr_nofail(fd);