[lttng-tools.git] / src / common / sessiond-comm / inet.c

/*
 * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License, version 2 only, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc., 51
 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#define _GNU_SOURCE
#include <assert.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <time.h>
#include <poll.h>

#include <common/common.h>

#include "inet.h"

#define MSEC_PER_SEC	1000
#define NSEC_PER_MSEC	1000000
#define RECONNECT_DELAY	200	/* ms */

/*
 * INET protocol operations.
 */
static const struct lttcomm_proto_ops inet_ops = {
	.bind = lttcomm_bind_inet_sock,
	.close = lttcomm_close_inet_sock,
	.connect = lttcomm_connect_inet_sock,
	.accept = lttcomm_accept_inet_sock,
	.listen = lttcomm_listen_inet_sock,
	.recvmsg = lttcomm_recvmsg_inet_sock,
	.sendmsg = lttcomm_sendmsg_inet_sock,
};

unsigned long lttcomm_inet_tcp_timeout;

/*
 * Creates an PF_INET socket.
 */
LTTNG_HIDDEN
int lttcomm_create_inet_sock(struct lttcomm_sock *sock, int type, int proto)
{
	int val = 1, ret;
	unsigned long timeout;

	/* Create server socket */
	if ((sock->fd = socket(PF_INET, type, proto)) < 0) {
		PERROR("socket inet");
		goto error;
	}

	sock->ops = &inet_ops;

	/*
	 * Set socket option to reuse the address.
	 */
	ret = setsockopt(sock->fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(int));
	if (ret < 0) {
		PERROR("setsockopt inet");
		goto error;
	}
	timeout = lttcomm_get_network_timeout();
	if (timeout) {
		ret = lttcomm_setsockopt_rcv_timeout(sock->fd, timeout);
		if (ret) {
			goto error;
		}
		ret = lttcomm_setsockopt_snd_timeout(sock->fd, timeout);
		if (ret) {
			goto error;
		}
	}

	return 0;

error:
	return -1;
}

/*
 * Bind socket and return.
 */
LTTNG_HIDDEN
int lttcomm_bind_inet_sock(struct lttcomm_sock *sock)
{
	int ret;

	ret = bind(sock->fd, &sock->sockaddr.addr.sin,
			sizeof(sock->sockaddr.addr.sin));
	if (ret < 0) {
		PERROR("bind inet");
	}

	return ret;
}

static
int connect_no_timeout(struct lttcomm_sock *sock)
{
	return connect(sock->fd, (struct sockaddr *) &sock->sockaddr.addr.sin,
			sizeof(sock->sockaddr.addr.sin));
}

/*
 * Return time_a - time_b  in milliseconds.
 */
static
unsigned long time_diff_ms(struct timespec *time_a,
		struct timespec *time_b)
{
	time_t sec_diff;
	long nsec_diff;
	unsigned long result_ms;

	sec_diff = time_a->tv_sec - time_b->tv_sec;
	nsec_diff = time_a->tv_nsec - time_b->tv_nsec;

	result_ms = sec_diff * MSEC_PER_SEC;
	result_ms += nsec_diff / NSEC_PER_MSEC;
	return result_ms;
}

static
int connect_with_timeout(struct lttcomm_sock *sock)
{
	unsigned long timeout = lttcomm_get_network_timeout();
	int ret, flags, connect_ret;
	struct timespec orig_time, cur_time;

	ret = fcntl(sock->fd, F_GETFL, 0);
	if (ret == -1) {
		PERROR("fcntl");
		return -1;
	}
	flags = ret;

	/* Set socket to nonblock */
	ret = fcntl(sock->fd, F_SETFL, flags | O_NONBLOCK);
	if (ret == -1) {
		PERROR("fcntl");
		return -1;
	}

	ret = clock_gettime(CLOCK_MONOTONIC, &orig_time);
	if (ret == -1) {
		PERROR("clock_gettime");
		return -1;
	}

	connect_ret = connect(sock->fd,
		(struct sockaddr *) &sock->sockaddr.addr.sin,
		sizeof(sock->sockaddr.addr.sin));
	if (connect_ret == -1 && errno != EAGAIN
			&& errno != EWOULDBLOCK
			&& errno != EINPROGRESS) {
		goto error;
	} else if (!connect_ret) {
		/* Connect succeeded */
		goto success;
	}

	/*
	 * Perform poll loop following EINPROGRESS recommendation from
	 * connect(2) man page.
	 */
	do {
		struct pollfd fds;

		fds.fd = sock->fd;
		fds.events = POLLOUT;
		fds.revents = 0;
		ret = poll(&fds, 1, RECONNECT_DELAY);
		if (ret < 0) {
			goto error;
		} else if (ret > 0) {
			int optval;
			socklen_t optval_len = sizeof(optval);

			if (!(fds.revents & POLLOUT)) {
				/* Either hup or error */
				errno = EPIPE;
				goto error;
			}
			/* got something */
			ret = getsockopt(sock->fd, SOL_SOCKET,
				SO_ERROR, &optval, &optval_len);
			if (ret) {
				goto error;
			}
			if (!optval) {
				connect_ret = 0;
				goto success;
			} else {
				goto error;
			}
		}
		/* ret == 0: timeout */
		ret = clock_gettime(CLOCK_MONOTONIC, &cur_time);
		if (ret == -1) {
			PERROR("clock_gettime");
			connect_ret = ret;
			goto error;
		}
	} while (time_diff_ms(&cur_time, &orig_time) < timeout);

	/* Timeout */
	errno = ETIMEDOUT;
	connect_ret = -1;

success:
	/* Restore initial flags */
	ret = fcntl(sock->fd, F_SETFL, flags);
	if (ret == -1) {
		PERROR("fcntl");
		/* Continue anyway */
	}
error:
	return connect_ret;
}

/*
 * Connect PF_INET socket.
 */
LTTNG_HIDDEN
int lttcomm_connect_inet_sock(struct lttcomm_sock *sock)
{
	int ret, closeret;

	if (lttcomm_get_network_timeout()) {
		ret = connect_with_timeout(sock);
	} else {
		ret = connect_no_timeout(sock);
	}
	if (ret < 0) {
		PERROR("connect");
		goto error_connect;
	}

	return ret;

error_connect:
	closeret = close(sock->fd);
	if (closeret) {
		PERROR("close inet");
	}

	return ret;
}

/*
 * Do an accept(2) on the sock and return the new lttcomm socket. The socket
 * MUST be bind(2) before.
 */
LTTNG_HIDDEN
struct lttcomm_sock *lttcomm_accept_inet_sock(struct lttcomm_sock *sock)
{
	int new_fd;
	socklen_t len;
	struct lttcomm_sock *new_sock;
	unsigned long timeout;

	if (sock->proto == LTTCOMM_SOCK_UDP) {
		/*
		 * accept(2) does not exist for UDP so simply return the passed socket.
		 */
		new_sock = sock;
		goto end;
	}

	new_sock = lttcomm_alloc_sock(sock->proto);
	if (new_sock == NULL) {
		goto error;
	}

	len = sizeof(new_sock->sockaddr.addr.sin);

	/* Blocking call */
	new_fd = accept(sock->fd, (struct sockaddr *) &new_sock->sockaddr.addr.sin,
			&len);
	if (new_fd < 0) {
		PERROR("accept inet");
		goto error;
	}
	timeout = lttcomm_get_network_timeout();
	if (timeout) {
		int ret;

		ret = lttcomm_setsockopt_rcv_timeout(new_fd, timeout);
		if (ret) {
			goto error;
		}
		ret = lttcomm_setsockopt_snd_timeout(new_fd, timeout);
		if (ret) {
			goto error;
		}
	}

	new_sock->fd = new_fd;
	new_sock->ops = &inet_ops;

end:
	return new_sock;

error:
	free(new_sock);
	return NULL;
}

/*
 * Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
 */
LTTNG_HIDDEN
int lttcomm_listen_inet_sock(struct lttcomm_sock *sock, int backlog)
{
	int ret;

	if (sock->proto == LTTCOMM_SOCK_UDP) {
		/* listen(2) does not exist for UDP so simply return success. */
		ret = 0;
		goto end;
	}

	/* Default listen backlog */
	if (backlog <= 0) {
		backlog = LTTNG_SESSIOND_COMM_MAX_LISTEN;
	}

	ret = listen(sock->fd, backlog);
	if (ret < 0) {
		PERROR("listen inet");
	}

end:
	return ret;
}

/*
 * Receive data of size len in put that data into the buf param. Using recvmsg
 * API.
 *
 * Return the size of received data.
 */
LTTNG_HIDDEN
ssize_t lttcomm_recvmsg_inet_sock(struct lttcomm_sock *sock, void *buf,
		size_t len, int flags)
{
	struct msghdr msg;
	struct iovec iov[1];
	ssize_t ret = -1;
	size_t len_last;

	memset(&msg, 0, sizeof(msg));

	iov[0].iov_base = buf;
	iov[0].iov_len = len;
	msg.msg_iov = iov;
	msg.msg_iovlen = 1;

	msg.msg_name = (struct sockaddr *) &sock->sockaddr.addr.sin;
	msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);

	do {
		len_last = iov[0].iov_len;
		ret = recvmsg(sock->fd, &msg, flags);
		if (ret > 0) {
			iov[0].iov_base += ret;
			iov[0].iov_len -= ret;
			assert(ret <= len_last);
		}
	} while ((ret > 0 && ret < len_last) || (ret < 0 && errno == EINTR));
	if (ret < 0) {
		PERROR("recvmsg inet");
	} else if (ret > 0) {
		ret = len;
	}
	/* Else ret = 0 meaning an orderly shutdown. */

	return ret;
}

/*
 * Send buf data of size len. Using sendmsg API.
 *
 * Return the size of sent data.
 */
LTTNG_HIDDEN
ssize_t lttcomm_sendmsg_inet_sock(struct lttcomm_sock *sock, void *buf,
		size_t len, int flags)
{
	struct msghdr msg;
	struct iovec iov[1];
	ssize_t ret = -1;

	memset(&msg, 0, sizeof(msg));

	iov[0].iov_base = buf;
	iov[0].iov_len = len;
	msg.msg_iov = iov;
	msg.msg_iovlen = 1;

	switch (sock->proto) {
	case LTTCOMM_SOCK_UDP:
		msg.msg_name = (struct sockaddr *) &sock->sockaddr.addr.sin;
		msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
		break;
	default:
		break;
	}

	do {
		ret = sendmsg(sock->fd, &msg, flags);
	} while (ret < 0 && errno == EINTR);
	if (ret < 0) {
		/*
		 * Only warn about EPIPE when quiet mode is deactivated.
		 * We consider EPIPE as expected.
		 */
		if (errno != EPIPE || !lttng_opt_quiet) {
			PERROR("sendmsg inet");
		}
	}

	return ret;
}

/*
 * Shutdown cleanly and close.
 */
LTTNG_HIDDEN
int lttcomm_close_inet_sock(struct lttcomm_sock *sock)
{
	int ret;

	/* Don't try to close an invalid marked socket */
	if (sock->fd == -1) {
		return 0;
	}

	ret = close(sock->fd);
	if (ret) {
		PERROR("close inet");
	}

	/* Mark socket */
	sock->fd = -1;

	return ret;
}

/*
 * Return value read from /proc or else 0 if value is not found.
 */
static unsigned long read_proc_value(const char *path)
{
	int ret, fd;
	ssize_t size_ret;
	long r_val;
	unsigned long val = 0;
	char buf[64];

	fd = open(path, O_RDONLY);
	if (fd < 0) {
		goto error;
	}

	size_ret = lttng_read(fd, buf, sizeof(buf));
	/*
	 * Allow reading a file smaller than buf, but keep space for
	 * final \0.
	 */
	if (size_ret < 0 || size_ret >= sizeof(buf)) {
		PERROR("read proc failed");
		goto error_close;
	}
	buf[size_ret] = '\0';

	errno = 0;
	r_val = strtol(buf, NULL, 10);
	if (errno != 0 || r_val < -1L) {
		val = 0;
		goto error_close;
	} else {
		if (r_val > 0) {
			val = r_val;
		}
	}

error_close:
	ret = close(fd);
	if (ret) {
		PERROR("close /proc value");
	}
error:
	return val;
}

LTTNG_HIDDEN
void lttcomm_inet_init(void)
{
	unsigned long syn_retries, fin_timeout, syn_timeout, env;

	env = lttcomm_get_network_timeout();
	if (env) {
		lttcomm_inet_tcp_timeout = env;
		goto end;
	}

	/* Assign default value and see if we can change it. */
	lttcomm_inet_tcp_timeout = DEFAULT_INET_TCP_TIMEOUT;

	syn_retries = read_proc_value(LTTCOMM_INET_PROC_SYN_RETRIES_PATH);
	fin_timeout = read_proc_value(LTTCOMM_INET_PROC_FIN_TIMEOUT_PATH);

	syn_timeout = syn_retries * LTTCOMM_INET_SYN_TIMEOUT_FACTOR;

	/*
	 * Get the maximum between the two possible timeout value and use that to
	 * get the maximum with the default timeout.
	 */
	lttcomm_inet_tcp_timeout = max_t(unsigned long,
			max_t(unsigned long, syn_timeout, fin_timeout),
			lttcomm_inet_tcp_timeout);

end:
	DBG("TCP inet operation timeout set to %lu sec", lttcomm_inet_tcp_timeout);
}
Commit	Line	Data
6364a07a DG	1	/*
	2	* Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
	3	*
	4	* This program is free software; you can redistribute it and/or modify it
	5	* under the terms of the GNU General Public License, version 2 only, as
	6	* published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful, but WITHOUT
	9	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	10	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	11	* more details.
	12	*
	13	* You should have received a copy of the GNU General Public License along with
	14	* this program; if not, write to the Free Software Foundation, Inc., 51
	15	* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	16	*/
	17
	18	#define _GNU_SOURCE
	19	#include <assert.h>
	20	#include <limits.h>
	21	#include <stdio.h>
	22	#include <stdlib.h>
	23	#include <string.h>
	24	#include <sys/stat.h>
	25	#include <sys/types.h>
	26	#include <unistd.h>
	27	#include <errno.h>
a655f4cf MD	28	#include <fcntl.h>
	29	#include <time.h>
	30	#include <poll.h>
6364a07a	31
90e535ef	32	#include <common/common.h>
6364a07a DG	33
	34	#include "inet.h"
	35
a655f4cf MD	36	#define MSEC_PER_SEC 1000
	37	#define NSEC_PER_MSEC 1000000
	38	#define RECONNECT_DELAY 200 /* ms */
	39
6364a07a DG	40	/*
	41	* INET protocol operations.
	42	*/
	43	static const struct lttcomm_proto_ops inet_ops = {
	44	.bind = lttcomm_bind_inet_sock,
	45	.close = lttcomm_close_inet_sock,
	46	.connect = lttcomm_connect_inet_sock,
	47	.accept = lttcomm_accept_inet_sock,
	48	.listen = lttcomm_listen_inet_sock,
	49	.recvmsg = lttcomm_recvmsg_inet_sock,
	50	.sendmsg = lttcomm_sendmsg_inet_sock,
	51	};
	52
d831c249 DG	53	unsigned long lttcomm_inet_tcp_timeout;
d831c249 DG	54
6364a07a DG	55	/*
	56	* Creates an PF_INET socket.
	57	*/
90e535ef	58	LTTNG_HIDDEN
6364a07a DG	59	int lttcomm_create_inet_sock(struct lttcomm_sock *sock, int type, int proto)
6364a07a DG	60	{
de5e9086	61	int val = 1, ret;
783a3b9a	62	unsigned long timeout;
6364a07a DG	63
	64	/* Create server socket */
	65	if ((sock->fd = socket(PF_INET, type, proto)) < 0) {
	66	PERROR("socket inet");
	67	goto error;
	68	}
	69
	70	sock->ops = &inet_ops;
	71
	72	/*
	73	* Set socket option to reuse the address.
	74	*/
	75	ret = setsockopt(sock->fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(int));
	76	if (ret < 0) {
	77	PERROR("setsockopt inet");
	78	goto error;
	79	}
783a3b9a MD	80	timeout = lttcomm_get_network_timeout();
	81	if (timeout) {
	82	ret = lttcomm_setsockopt_rcv_timeout(sock->fd, timeout);
	83	if (ret) {
	84	goto error;
	85	}
	86	ret = lttcomm_setsockopt_snd_timeout(sock->fd, timeout);
	87	if (ret) {
	88	goto error;
	89	}
	90	}
6364a07a DG	91
	92	return 0;
	93
	94	error:
	95	return -1;
	96	}
	97
	98	/*
	99	* Bind socket and return.
	100	*/
90e535ef	101	LTTNG_HIDDEN
6364a07a DG	102	int lttcomm_bind_inet_sock(struct lttcomm_sock *sock)
	103	{
	104	int ret;
	105
	106	ret = bind(sock->fd, &sock->sockaddr.addr.sin,
	107	sizeof(sock->sockaddr.addr.sin));
	108	if (ret < 0) {
	109	PERROR("bind inet");
	110	}
	111
	112	return ret;
	113	}
	114
a655f4cf MD	115	static
	116	int connect_no_timeout(struct lttcomm_sock *sock)
	117	{
	118	return connect(sock->fd, (struct sockaddr *) &sock->sockaddr.addr.sin,
	119	sizeof(sock->sockaddr.addr.sin));
	120	}
	121
	122	/*
	123	* Return time_a - time_b in milliseconds.
	124	*/
	125	static
	126	unsigned long time_diff_ms(struct timespec *time_a,
	127	struct timespec *time_b)
	128	{
	129	time_t sec_diff;
	130	long nsec_diff;
	131	unsigned long result_ms;
	132
	133	sec_diff = time_a->tv_sec - time_b->tv_sec;
	134	nsec_diff = time_a->tv_nsec - time_b->tv_nsec;
	135
	136	result_ms = sec_diff * MSEC_PER_SEC;
	137	result_ms += nsec_diff / NSEC_PER_MSEC;
	138	return result_ms;
	139	}
	140
	141	static
	142	int connect_with_timeout(struct lttcomm_sock *sock)
	143	{
	144	unsigned long timeout = lttcomm_get_network_timeout();
	145	int ret, flags, connect_ret;
	146	struct timespec orig_time, cur_time;
	147
	148	ret = fcntl(sock->fd, F_GETFL, 0);
	149	if (ret == -1) {
	150	PERROR("fcntl");
	151	return -1;
	152	}
	153	flags = ret;
	154
	155	/* Set socket to nonblock */
	156	ret = fcntl(sock->fd, F_SETFL, flags \| O_NONBLOCK);
	157	if (ret == -1) {
	158	PERROR("fcntl");
	159	return -1;
	160	}
	161
	162	ret = clock_gettime(CLOCK_MONOTONIC, &orig_time);
	163	if (ret == -1) {
	164	PERROR("clock_gettime");
	165	return -1;
	166	}
	167
	168	connect_ret = connect(sock->fd,
	169	(struct sockaddr *) &sock->sockaddr.addr.sin,
	170	sizeof(sock->sockaddr.addr.sin));
	171	if (connect_ret == -1 && errno != EAGAIN
	172	&& errno != EWOULDBLOCK
	173	&& errno != EINPROGRESS) {
	174	goto error;
	175	} else if (!connect_ret) {
	176	/* Connect succeeded */
	177	goto success;
	178	}
179
180	/*
181	* Perform poll loop following EINPROGRESS recommendation from
182	* connect(2) man page.
183	*/
184	do {
185	struct pollfd fds;
186
187	fds.fd = sock->fd;
188	fds.events = POLLOUT;
189	fds.revents = 0;
190	ret = poll(&fds, 1, RECONNECT_DELAY);
191	if (ret < 0) {
192	goto error;
193	} else if (ret > 0) {
194	int optval;
195	socklen_t optval_len = sizeof(optval);
196
197	if (!(fds.revents & POLLOUT)) {
198	/* Either hup or error */
199	errno = EPIPE;
200	goto error;
201	}
202	/* got something */
203	ret = getsockopt(sock->fd, SOL_SOCKET,
204	SO_ERROR, &optval, &optval_len);
205	if (ret) {
206	goto error;
207	}
208	if (!optval) {
209	connect_ret = 0;
210	goto success;
211	} else {
212	goto error;
213	}
214	}
215	/* ret == 0: timeout */
216	ret = clock_gettime(CLOCK_MONOTONIC, &cur_time);
217	if (ret == -1) {
218	PERROR("clock_gettime");
219	connect_ret = ret;
220	goto error;
221	}
222	} while (time_diff_ms(&cur_time, &orig_time) < timeout);
223
224	/* Timeout */
225	errno = ETIMEDOUT;
226	connect_ret = -1;
227
228	success:
229	/* Restore initial flags */
230	ret = fcntl(sock->fd, F_SETFL, flags);
231	if (ret == -1) {
232	PERROR("fcntl");
233	/* Continue anyway */
234	}
235	error:
236	return connect_ret;
237	}
238
6364a07a DG	239	/*
	240	* Connect PF_INET socket.
	241	*/
90e535ef	242	LTTNG_HIDDEN
6364a07a DG	243	int lttcomm_connect_inet_sock(struct lttcomm_sock *sock)
	244	{
	245	int ret, closeret;
	246
a655f4cf MD	247	if (lttcomm_get_network_timeout()) {
	248	ret = connect_with_timeout(sock);
	249	} else {
	250	ret = connect_no_timeout(sock);
	251	}
6364a07a	252	if (ret < 0) {
82c05d47	253	PERROR("connect");
6364a07a DG	254	goto error_connect;
	255	}
	256
	257	return ret;
	258
	259	error_connect:
	260	closeret = close(sock->fd);
	261	if (closeret) {
	262	PERROR("close inet");
	263	}
	264
	265	return ret;
	266	}
	267
	268	/*
	269	* Do an accept(2) on the sock and return the new lttcomm socket. The socket
	270	* MUST be bind(2) before.
	271	*/
90e535ef	272	LTTNG_HIDDEN
6364a07a DG	273	struct lttcomm_sock lttcomm_accept_inet_sock(struct lttcomm_sock sock)
	274	{
	275	int new_fd;
88a5db70	276	socklen_t len;
6364a07a	277	struct lttcomm_sock *new_sock;
71c648d8	278	unsigned long timeout;
6364a07a DG	279
	280	if (sock->proto == LTTCOMM_SOCK_UDP) {
	281	/*
	282	* accept(2) does not exist for UDP so simply return the passed socket.
	283	*/
	284	new_sock = sock;
	285	goto end;
	286	}
	287
de5e9086	288	new_sock = lttcomm_alloc_sock(sock->proto);
6364a07a DG	289	if (new_sock == NULL) {
	290	goto error;
	291	}
	292
88a5db70 DG	293	len = sizeof(new_sock->sockaddr.addr.sin);
88a5db70 DG	294
6364a07a DG	295	/* Blocking call */
	296	new_fd = accept(sock->fd, (struct sockaddr *) &new_sock->sockaddr.addr.sin,
	297	&len);
	298	if (new_fd < 0) {
	299	PERROR("accept inet");
	300	goto error;
	301	}
71c648d8 JG	302	timeout = lttcomm_get_network_timeout();
	303	if (timeout) {
	304	int ret;
	305
	306	ret = lttcomm_setsockopt_rcv_timeout(new_fd, timeout);
	307	if (ret) {
	308	goto error;
	309	}
	310	ret = lttcomm_setsockopt_snd_timeout(new_fd, timeout);
	311	if (ret) {
	312	goto error;
	313	}
	314	}
6364a07a DG	315
6364a07a DG	316	new_sock->fd = new_fd;
de5e9086	317	new_sock->ops = &inet_ops;
6364a07a DG	318
	319	end:
	320	return new_sock;
	321
	322	error:
	323	free(new_sock);
	324	return NULL;
	325	}
	326
	327	/*
	328	* Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
	329	*/
90e535ef	330	LTTNG_HIDDEN
6364a07a DG	331	int lttcomm_listen_inet_sock(struct lttcomm_sock *sock, int backlog)
	332	{
	333	int ret;
	334
	335	if (sock->proto == LTTCOMM_SOCK_UDP) {
	336	/* listen(2) does not exist for UDP so simply return success. */
	337	ret = 0;
	338	goto end;
	339	}
	340
	341	/* Default listen backlog */
	342	if (backlog <= 0) {
	343	backlog = LTTNG_SESSIOND_COMM_MAX_LISTEN;
	344	}
	345
	346	ret = listen(sock->fd, backlog);
	347	if (ret < 0) {
	348	PERROR("listen inet");
	349	}
	350
	351	end:
	352	return ret;
	353	}
	354
	355	/*
	356	* Receive data of size len in put that data into the buf param. Using recvmsg
	357	* API.
	358	*
	359	* Return the size of received data.
	360	*/
90e535ef	361	LTTNG_HIDDEN
6364a07a DG	362	ssize_t lttcomm_recvmsg_inet_sock(struct lttcomm_sock sock, void buf,
	363	size_t len, int flags)
	364	{
	365	struct msghdr msg;
	366	struct iovec iov[1];
	367	ssize_t ret = -1;
7c5aef62	368	size_t len_last;
6364a07a DG	369
	370	memset(&msg, 0, sizeof(msg));
	371
	372	iov[0].iov_base = buf;
	373	iov[0].iov_len = len;
	374	msg.msg_iov = iov;
	375	msg.msg_iovlen = 1;
	376
	377	msg.msg_name = (struct sockaddr *) &sock->sockaddr.addr.sin;
	378	msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
	379
6364a07a	380	do {
7c5aef62	381	len_last = iov[0].iov_len;
6364a07a	382	ret = recvmsg(sock->fd, &msg, flags);
7c5aef62 DG	383	if (ret > 0) {
	384	iov[0].iov_base += ret;
	385	iov[0].iov_len -= ret;
	386	assert(ret <= len_last);
	387	}
	388	} while ((ret > 0 && ret < len_last) \|\| (ret < 0 && errno == EINTR));
6364a07a DG	389	if (ret < 0) {
6364a07a DG	390	PERROR("recvmsg inet");
7c5aef62 DG	391	} else if (ret > 0) {
7c5aef62 DG	392	ret = len;
6364a07a	393	}
7c5aef62	394	/* Else ret = 0 meaning an orderly shutdown. */
6364a07a DG	395
	396	return ret;
	397	}
	398
	399	/*
	400	* Send buf data of size len. Using sendmsg API.
	401	*
	402	* Return the size of sent data.
	403	*/
90e535ef	404	LTTNG_HIDDEN
6364a07a DG	405	ssize_t lttcomm_sendmsg_inet_sock(struct lttcomm_sock sock, void buf,
	406	size_t len, int flags)
	407	{
	408	struct msghdr msg;
	409	struct iovec iov[1];
	410	ssize_t ret = -1;
	411
	412	memset(&msg, 0, sizeof(msg));
	413
	414	iov[0].iov_base = buf;
	415	iov[0].iov_len = len;
	416	msg.msg_iov = iov;
	417	msg.msg_iovlen = 1;
	418
	419	switch (sock->proto) {
	420	case LTTCOMM_SOCK_UDP:
	421	msg.msg_name = (struct sockaddr *) &sock->sockaddr.addr.sin;
	422	msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
	423	break;
	424	default:
	425	break;
	426	}
	427
	428	do {
	429	ret = sendmsg(sock->fd, &msg, flags);
	430	} while (ret < 0 && errno == EINTR);
	431	if (ret < 0) {
	432	/*
	433	* Only warn about EPIPE when quiet mode is deactivated.
	434	* We consider EPIPE as expected.
	435	*/
	436	if (errno != EPIPE \|\| !lttng_opt_quiet) {
	437	PERROR("sendmsg inet");
	438	}
	439	}
	440
	441	return ret;
	442	}
	443
	444	/*
	445	* Shutdown cleanly and close.
	446	*/
90e535ef	447	LTTNG_HIDDEN
6364a07a DG	448	int lttcomm_close_inet_sock(struct lttcomm_sock *sock)
6364a07a DG	449	{
6e742359	450	int ret;
6364a07a	451
de5e9086	452	/* Don't try to close an invalid marked socket */
6364a07a DG	453	if (sock->fd == -1) {
	454	return 0;
	455	}
	456
6e742359 DG	457	ret = close(sock->fd);
6e742359 DG	458	if (ret) {
6364a07a DG	459	PERROR("close inet");
	460	}
	461
	462	/* Mark socket */
	463	sock->fd = -1;
	464
	465	return ret;
	466	}
d831c249 DG	467
	468	/*
	469	* Return value read from /proc or else 0 if value is not found.
	470	*/
	471	static unsigned long read_proc_value(const char *path)
	472	{
	473	int ret, fd;
6cd525e8	474	ssize_t size_ret;
d831c249 DG	475	long r_val;
	476	unsigned long val = 0;
	477	char buf[64];
	478
	479	fd = open(path, O_RDONLY);
	480	if (fd < 0) {
	481	goto error;
	482	}
	483
6cd525e8 MD	484	size_ret = lttng_read(fd, buf, sizeof(buf));
	485	/*
	486	* Allow reading a file smaller than buf, but keep space for
	487	* final \0.
	488	*/
	489	if (size_ret < 0 \|\| size_ret >= sizeof(buf)) {
d831c249 DG	490	PERROR("read proc failed");
	491	goto error_close;
	492	}
6cd525e8	493	buf[size_ret] = '\0';
d831c249 DG	494
	495	errno = 0;
	496	r_val = strtol(buf, NULL, 10);
	497	if (errno != 0 \|\| r_val < -1L) {
	498	val = 0;
	499	goto error_close;
	500	} else {
	501	if (r_val > 0) {
	502	val = r_val;
	503	}
	504	}
	505
	506	error_close:
	507	ret = close(fd);
	508	if (ret) {
	509	PERROR("close /proc value");
	510	}
	511	error:
	512	return val;
	513	}
	514
	515	LTTNG_HIDDEN
	516	void lttcomm_inet_init(void)
	517	{
18eed43f DG	518	unsigned long syn_retries, fin_timeout, syn_timeout, env;
	519
	520	env = lttcomm_get_network_timeout();
	521	if (env) {
	522	lttcomm_inet_tcp_timeout = env;
	523	goto end;
	524	}
d831c249 DG	525
	526	/* Assign default value and see if we can change it. */
	527	lttcomm_inet_tcp_timeout = DEFAULT_INET_TCP_TIMEOUT;
	528
	529	syn_retries = read_proc_value(LTTCOMM_INET_PROC_SYN_RETRIES_PATH);
	530	fin_timeout = read_proc_value(LTTCOMM_INET_PROC_FIN_TIMEOUT_PATH);
	531
	532	syn_timeout = syn_retries * LTTCOMM_INET_SYN_TIMEOUT_FACTOR;
	533
	534	/*
	535	* Get the maximum between the two possible timeout value and use that to
	536	* get the maximum with the default timeout.
	537	*/
	538	lttcomm_inet_tcp_timeout = max_t(unsigned long,
	539	max_t(unsigned long, syn_timeout, fin_timeout),
	540	lttcomm_inet_tcp_timeout);
	541
18eed43f	542	end:
d831c249 DG	543	DBG("TCP inet operation timeout set to %lu sec", lttcomm_inet_tcp_timeout);
d831c249 DG	544	}