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

/*
 * Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
 *
 * SPDX-License-Identifier: GPL-2.0-only
 *
 */

#define _LGPL_SOURCE
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
#include <common/compat/time.h>
#include <poll.h>

#include <common/common.h>
#include <common/time.h>
#include <common/compat/errno.h>

#include "inet.h"

#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.
 */
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.
 */
int lttcomm_bind_inet_sock(struct lttcomm_sock *sock)
{
	return bind(sock->fd,
			(const struct sockaddr *) ALIGNED_CONST_PTR(
					sock->sockaddr.addr.sin),
			sizeof(sock->sockaddr.addr.sin));
}

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

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;
	unsigned long diff_ms;

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

	connect_ret = connect(sock->fd,
			(const struct sockaddr *) ALIGNED_CONST_PTR(
					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;
	}

	DBG("Asynchronous connect for sock %d, performing polling with"
			" timeout: %lums", sock->fd, timeout);
	/*
	 * 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) {
				PERROR("getsockopt");
				goto error;
			}
			if (!optval) {
				connect_ret = 0;
				goto success;
			} else {
				/* Get actual connect() errno from opt_val */
				errno = optval;
				goto error;
			}
		}
		/* ret == 0: timeout */
		ret = lttng_clock_gettime(CLOCK_MONOTONIC, &cur_time);
		if (ret == -1) {
			PERROR("clock_gettime");
			connect_ret = ret;
			goto error;
		}
		if (timespec_to_ms(timespec_abs_diff(cur_time, orig_time), &diff_ms) < 0) {
			ERR("timespec_to_ms input overflows milliseconds output");
			connect_ret = -1;
			goto error;
		}
	} while (diff_ms < 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.
 */
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.
 */
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;
	struct sockaddr_in new_addr = {};

	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_addr);

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

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

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

end:
	return new_sock;

error_close:
	if (close(new_fd) < 0) {
		PERROR("accept inet close fd");
	}

error:
	free(new_sock);
	return NULL;
}

/*
 * Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
 */
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.
 */
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;
	struct sockaddr_in addr = sock->sockaddr.addr.sin;

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

	do {
		len_last = iov[0].iov_len;
		ret = recvmsg(sock->fd, &msg, flags);
		if (ret > 0) {
			if (flags & MSG_DONTWAIT) {
				goto end;
			}
			iov[0].iov_base += ret;
			iov[0].iov_len -= ret;
			LTTNG_ASSERT(ret <= len_last);
		}
	} while ((ret > 0 && ret < len_last) || (ret < 0 && errno == EINTR));

	if (ret < 0) {
		if (errno == EAGAIN && flags & MSG_DONTWAIT) {
			/*
			 * EAGAIN is expected in non-blocking mode and should
			 * not be reported as an error. Moreover, if no data
			 * was read, 0 must not be returned as it would be
			 * interpreted as an orderly shutdown of the socket.
			 */
			goto end;
		}
		PERROR("recvmsg inet");
	} else if (ret > 0) {
		ret = len;
	}
	/* Else ret = 0 meaning an orderly shutdown. */
end:
	return ret;
}

/*
 * Send buf data of size len. Using sendmsg API.
 *
 * Return the size of sent data.
 */
ssize_t lttcomm_sendmsg_inet_sock(struct lttcomm_sock *sock, const 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 = (void *) buf;
	iov[0].iov_len = len;
	msg.msg_iov = iov;
	msg.msg_iovlen = 1;

	switch (sock->proto) {
	case LTTCOMM_SOCK_UDP:
	{
		struct sockaddr_in addr = sock->sockaddr.addr.sin;

		msg.msg_name = (struct sockaddr *) &addr;
		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.
 */
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;
}

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	1	/*
ab5be9fa	2	* Copyright (C) 2012 David Goulet <dgoulet@efficios.com>
6364a07a	3	*
ab5be9fa	4	* SPDX-License-Identifier: GPL-2.0-only
6364a07a	5	*
6364a07a DG	6	*/
6364a07a DG	7
6c1c0768	8	#define _LGPL_SOURCE
6364a07a DG	9	#include <limits.h>
	10	#include <stdio.h>
	11	#include <stdlib.h>
	12	#include <string.h>
	13	#include <sys/stat.h>
	14	#include <sys/types.h>
	15	#include <unistd.h>
a655f4cf	16	#include <fcntl.h>
389fbf04	17	#include <common/compat/time.h>
a655f4cf	18	#include <poll.h>
6364a07a	19
90e535ef	20	#include <common/common.h>
395d6b02	21	#include <common/time.h>
edf4b93e	22	#include <common/compat/errno.h>
6364a07a DG	23
	24	#include "inet.h"
	25
a655f4cf MD	26	#define RECONNECT_DELAY 200 /* ms */
a655f4cf MD	27
6364a07a DG	28	/*
	29	* INET protocol operations.
	30	*/
	31	static const struct lttcomm_proto_ops inet_ops = {
	32	.bind = lttcomm_bind_inet_sock,
	33	.close = lttcomm_close_inet_sock,
	34	.connect = lttcomm_connect_inet_sock,
	35	.accept = lttcomm_accept_inet_sock,
	36	.listen = lttcomm_listen_inet_sock,
	37	.recvmsg = lttcomm_recvmsg_inet_sock,
	38	.sendmsg = lttcomm_sendmsg_inet_sock,
	39	};
	40
d831c249 DG	41	unsigned long lttcomm_inet_tcp_timeout;
d831c249 DG	42
6364a07a DG	43	/*
	44	* Creates an PF_INET socket.
	45	*/
	46	int lttcomm_create_inet_sock(struct lttcomm_sock *sock, int type, int proto)
	47	{
de5e9086	48	int val = 1, ret;
783a3b9a	49	unsigned long timeout;
6364a07a DG	50
	51	/* Create server socket */
	52	if ((sock->fd = socket(PF_INET, type, proto)) < 0) {
	53	PERROR("socket inet");
	54	goto error;
	55	}
	56
	57	sock->ops = &inet_ops;
	58
	59	/*
	60	* Set socket option to reuse the address.
	61	*/
	62	ret = setsockopt(sock->fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(int));
	63	if (ret < 0) {
	64	PERROR("setsockopt inet");
	65	goto error;
	66	}
783a3b9a MD	67	timeout = lttcomm_get_network_timeout();
	68	if (timeout) {
	69	ret = lttcomm_setsockopt_rcv_timeout(sock->fd, timeout);
	70	if (ret) {
	71	goto error;
	72	}
	73	ret = lttcomm_setsockopt_snd_timeout(sock->fd, timeout);
	74	if (ret) {
	75	goto error;
	76	}
	77	}
6364a07a DG	78
	79	return 0;
	80
	81	error:
	82	return -1;
	83	}
	84
	85	/*
	86	* Bind socket and return.
	87	*/
	88	int lttcomm_bind_inet_sock(struct lttcomm_sock *sock)
	89	{
2288467f	90	return bind(sock->fd,
1a65bbb8 JG	91	(const struct sockaddr *) ALIGNED_CONST_PTR(
1a65bbb8 JG	92	sock->sockaddr.addr.sin),
6364a07a	93	sizeof(sock->sockaddr.addr.sin));
6364a07a DG	94	}
6364a07a DG	95
a655f4cf MD	96	static
	97	int connect_no_timeout(struct lttcomm_sock *sock)
	98	{
1a65bbb8 JG	99	return connect(sock->fd,
	100	(const struct sockaddr *) ALIGNED_CONST_PTR(
	101	sock->sockaddr.addr.sin),
a655f4cf MD	102	sizeof(sock->sockaddr.addr.sin));
	103	}
	104
a655f4cf MD	105	static
	106	int connect_with_timeout(struct lttcomm_sock *sock)
	107	{
	108	unsigned long timeout = lttcomm_get_network_timeout();
	109	int ret, flags, connect_ret;
	110	struct timespec orig_time, cur_time;
2daf6502	111	unsigned long diff_ms;
a655f4cf MD	112
	113	ret = fcntl(sock->fd, F_GETFL, 0);
	114	if (ret == -1) {
	115	PERROR("fcntl");
	116	return -1;
	117	}
	118	flags = ret;
	119
	120	/* Set socket to nonblock */
	121	ret = fcntl(sock->fd, F_SETFL, flags \| O_NONBLOCK);
	122	if (ret == -1) {
	123	PERROR("fcntl");
	124	return -1;
	125	}
	126
389fbf04	127	ret = lttng_clock_gettime(CLOCK_MONOTONIC, &orig_time);
a655f4cf MD	128	if (ret == -1) {
	129	PERROR("clock_gettime");
	130	return -1;
	131	}
	132
	133	connect_ret = connect(sock->fd,
1a65bbb8 JG	134	(const struct sockaddr *) ALIGNED_CONST_PTR(
	135	sock->sockaddr.addr.sin),
	136	sizeof(sock->sockaddr.addr.sin));
	137	if (connect_ret == -1 && errno != EAGAIN && errno != EWOULDBLOCK &&
	138	errno != EINPROGRESS) {
a655f4cf MD	139	goto error;
	140	} else if (!connect_ret) {
	141	/* Connect succeeded */
	142	goto success;
	143	}
	144
48ac9596 JR	145	DBG("Asynchronous connect for sock %d, performing polling with"
48ac9596 JR	146	" timeout: %lums", sock->fd, timeout);
a655f4cf MD	147	/*
	148	* Perform poll loop following EINPROGRESS recommendation from
	149	* connect(2) man page.
	150	*/
	151	do {
	152	struct pollfd fds;
	153
	154	fds.fd = sock->fd;
	155	fds.events = POLLOUT;
	156	fds.revents = 0;
	157	ret = poll(&fds, 1, RECONNECT_DELAY);
	158	if (ret < 0) {
	159	goto error;
	160	} else if (ret > 0) {
	161	int optval;
	162	socklen_t optval_len = sizeof(optval);
	163
	164	if (!(fds.revents & POLLOUT)) {
	165	/* Either hup or error */
	166	errno = EPIPE;
	167	goto error;
	168	}
	169	/* got something */
	170	ret = getsockopt(sock->fd, SOL_SOCKET,
	171	SO_ERROR, &optval, &optval_len);
	172	if (ret) {
48ac9596	173	PERROR("getsockopt");
a655f4cf MD	174	goto error;
	175	}
	176	if (!optval) {
	177	connect_ret = 0;
	178	goto success;
	179	} else {
48ac9596 JR	180	/* Get actual connect() errno from opt_val */
48ac9596 JR	181	errno = optval;
a655f4cf MD	182	goto error;
	183	}
	184	}
	185	/* ret == 0: timeout */
389fbf04	186	ret = lttng_clock_gettime(CLOCK_MONOTONIC, &cur_time);
a655f4cf MD	187	if (ret == -1) {
	188	PERROR("clock_gettime");
	189	connect_ret = ret;
	190	goto error;
	191	}
2daf6502 MD	192	if (timespec_to_ms(timespec_abs_diff(cur_time, orig_time), &diff_ms) < 0) {
	193	ERR("timespec_to_ms input overflows milliseconds output");
	194	connect_ret = -1;
	195	goto error;
	196	}
	197	} while (diff_ms < timeout);
a655f4cf MD	198
	199	/* Timeout */
	200	errno = ETIMEDOUT;
	201	connect_ret = -1;
	202
	203	success:
	204	/* Restore initial flags */
	205	ret = fcntl(sock->fd, F_SETFL, flags);
	206	if (ret == -1) {
	207	PERROR("fcntl");
	208	/* Continue anyway */
	209	}
	210	error:
	211	return connect_ret;
	212	}
	213
6364a07a DG	214	/*
	215	* Connect PF_INET socket.
	216	*/
	217	int lttcomm_connect_inet_sock(struct lttcomm_sock *sock)
	218	{
	219	int ret, closeret;
	220
a655f4cf MD	221	if (lttcomm_get_network_timeout()) {
	222	ret = connect_with_timeout(sock);
	223	} else {
	224	ret = connect_no_timeout(sock);
	225	}
6364a07a	226	if (ret < 0) {
82c05d47	227	PERROR("connect");
6364a07a DG	228	goto error_connect;
	229	}
	230
	231	return ret;
	232
	233	error_connect:
	234	closeret = close(sock->fd);
	235	if (closeret) {
	236	PERROR("close inet");
	237	}
	238
	239	return ret;
	240	}
	241
	242	/*
	243	* Do an accept(2) on the sock and return the new lttcomm socket. The socket
	244	* MUST be bind(2) before.
	245	*/
	246	struct lttcomm_sock lttcomm_accept_inet_sock(struct lttcomm_sock sock)
	247	{
	248	int new_fd;
88a5db70	249	socklen_t len;
6364a07a	250	struct lttcomm_sock *new_sock;
71c648d8	251	unsigned long timeout;
1a65bbb8	252	struct sockaddr_in new_addr = {};
6364a07a DG	253
	254	if (sock->proto == LTTCOMM_SOCK_UDP) {
	255	/*
	256	* accept(2) does not exist for UDP so simply return the passed socket.
	257	*/
	258	new_sock = sock;
	259	goto end;
	260	}
	261
de5e9086	262	new_sock = lttcomm_alloc_sock(sock->proto);
6364a07a DG	263	if (new_sock == NULL) {
	264	goto error;
	265	}
	266
1a65bbb8	267	len = sizeof(new_addr);
88a5db70	268
6364a07a	269	/* Blocking call */
1a65bbb8	270	new_fd = accept(sock->fd, (struct sockaddr *) &new_addr, &len);
6364a07a DG	271	if (new_fd < 0) {
	272	PERROR("accept inet");
	273	goto error;
	274	}
1a65bbb8	275	new_sock->sockaddr.addr.sin = new_addr;
71c648d8 JG	276	timeout = lttcomm_get_network_timeout();
	277	if (timeout) {
	278	int ret;
	279
	280	ret = lttcomm_setsockopt_rcv_timeout(new_fd, timeout);
	281	if (ret) {
475cd9fa	282	goto error_close;
71c648d8 JG	283	}
	284	ret = lttcomm_setsockopt_snd_timeout(new_fd, timeout);
	285	if (ret) {
475cd9fa	286	goto error_close;
71c648d8 JG	287	}
71c648d8 JG	288	}
6364a07a DG	289
6364a07a DG	290	new_sock->fd = new_fd;
de5e9086	291	new_sock->ops = &inet_ops;
6364a07a DG	292
	293	end:
	294	return new_sock;
	295
475cd9fa DG	296	error_close:
	297	if (close(new_fd) < 0) {
	298	PERROR("accept inet close fd");
	299	}
	300
6364a07a DG	301	error:
	302	free(new_sock);
	303	return NULL;
	304	}
	305
	306	/*
	307	* Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
	308	*/
	309	int lttcomm_listen_inet_sock(struct lttcomm_sock *sock, int backlog)
	310	{
	311	int ret;
	312
	313	if (sock->proto == LTTCOMM_SOCK_UDP) {
	314	/* listen(2) does not exist for UDP so simply return success. */
	315	ret = 0;
	316	goto end;
	317	}
	318
	319	/* Default listen backlog */
	320	if (backlog <= 0) {
	321	backlog = LTTNG_SESSIOND_COMM_MAX_LISTEN;
	322	}
	323
	324	ret = listen(sock->fd, backlog);
	325	if (ret < 0) {
	326	PERROR("listen inet");
	327	}
	328
	329	end:
	330	return ret;
	331	}
	332
	333	/*
	334	* Receive data of size len in put that data into the buf param. Using recvmsg
	335	* API.
	336	*
	337	* Return the size of received data.
	338	*/
	339	ssize_t lttcomm_recvmsg_inet_sock(struct lttcomm_sock sock, void buf,
	340	size_t len, int flags)
	341	{
	342	struct msghdr msg;
	343	struct iovec iov[1];
	344	ssize_t ret = -1;
7c5aef62	345	size_t len_last;
1a65bbb8	346	struct sockaddr_in addr = sock->sockaddr.addr.sin;
6364a07a DG	347
	348	memset(&msg, 0, sizeof(msg));
	349
	350	iov[0].iov_base = buf;
	351	iov[0].iov_len = len;
	352	msg.msg_iov = iov;
	353	msg.msg_iovlen = 1;
	354
1a65bbb8	355	msg.msg_name = (struct sockaddr *) &addr;
6364a07a DG	356	msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
6364a07a DG	357
6364a07a	358	do {
7c5aef62	359	len_last = iov[0].iov_len;
6364a07a	360	ret = recvmsg(sock->fd, &msg, flags);
7c5aef62	361	if (ret > 0) {
5312a3ed JG	362	if (flags & MSG_DONTWAIT) {
	363	goto end;
	364	}
7c5aef62 DG	365	iov[0].iov_base += ret;
7c5aef62 DG	366	iov[0].iov_len -= ret;
a0377dfe	367	LTTNG_ASSERT(ret <= len_last);
7c5aef62 DG	368	}
7c5aef62 DG	369	} while ((ret > 0 && ret < len_last) \|\| (ret < 0 && errno == EINTR));
5312a3ed	370
6364a07a	371	if (ret < 0) {
c2e8c366 JG	372	if (errno == EAGAIN && flags & MSG_DONTWAIT) {
	373	/*
	374	* EAGAIN is expected in non-blocking mode and should
	375	* not be reported as an error. Moreover, if no data
	376	* was read, 0 must not be returned as it would be
	377	* interpreted as an orderly shutdown of the socket.
	378	*/
	379	goto end;
	380	}
6364a07a	381	PERROR("recvmsg inet");
7c5aef62 DG	382	} else if (ret > 0) {
7c5aef62 DG	383	ret = len;
6364a07a	384	}
7c5aef62	385	/* Else ret = 0 meaning an orderly shutdown. */
5312a3ed	386	end:
6364a07a DG	387	return ret;
	388	}
	389
	390	/*
	391	* Send buf data of size len. Using sendmsg API.
	392	*
	393	* Return the size of sent data.
	394	*/
c2d69327	395	ssize_t lttcomm_sendmsg_inet_sock(struct lttcomm_sock sock, const void buf,
6364a07a DG	396	size_t len, int flags)
	397	{
	398	struct msghdr msg;
	399	struct iovec iov[1];
	400	ssize_t ret = -1;
	401
	402	memset(&msg, 0, sizeof(msg));
	403
c2d69327	404	iov[0].iov_base = (void *) buf;
6364a07a DG	405	iov[0].iov_len = len;
	406	msg.msg_iov = iov;
	407	msg.msg_iovlen = 1;
	408
	409	switch (sock->proto) {
	410	case LTTCOMM_SOCK_UDP:
1a65bbb8 JG	411	{
	412	struct sockaddr_in addr = sock->sockaddr.addr.sin;
	413
	414	msg.msg_name = (struct sockaddr *) &addr;
6364a07a DG	415	msg.msg_namelen = sizeof(sock->sockaddr.addr.sin);
6364a07a DG	416	break;
1a65bbb8	417	}
6364a07a DG	418	default:
	419	break;
	420	}
	421
	422	do {
	423	ret = sendmsg(sock->fd, &msg, flags);
	424	} while (ret < 0 && errno == EINTR);
	425	if (ret < 0) {
	426	/*
	427	* Only warn about EPIPE when quiet mode is deactivated.
	428	* We consider EPIPE as expected.
	429	*/
	430	if (errno != EPIPE \|\| !lttng_opt_quiet) {
	431	PERROR("sendmsg inet");
	432	}
	433	}
	434
	435	return ret;
	436	}
	437
	438	/*
	439	* Shutdown cleanly and close.
	440	*/
	441	int lttcomm_close_inet_sock(struct lttcomm_sock *sock)
	442	{
6e742359	443	int ret;
6364a07a	444
de5e9086	445	/* Don't try to close an invalid marked socket */
6364a07a DG	446	if (sock->fd == -1) {
	447	return 0;
	448	}
	449
6e742359 DG	450	ret = close(sock->fd);
6e742359 DG	451	if (ret) {
6364a07a DG	452	PERROR("close inet");
	453	}
	454
	455	/* Mark socket */
	456	sock->fd = -1;
	457
	458	return ret;
	459	}
d831c249 DG	460
	461	/*
	462	* Return value read from /proc or else 0 if value is not found.
	463	*/
	464	static unsigned long read_proc_value(const char *path)
	465	{
	466	int ret, fd;
6cd525e8	467	ssize_t size_ret;
d831c249 DG	468	long r_val;
	469	unsigned long val = 0;
	470	char buf[64];
	471
	472	fd = open(path, O_RDONLY);
	473	if (fd < 0) {
	474	goto error;
	475	}
	476
6cd525e8 MD	477	size_ret = lttng_read(fd, buf, sizeof(buf));
	478	/*
	479	* Allow reading a file smaller than buf, but keep space for
	480	* final \0.
	481	*/
	482	if (size_ret < 0 \|\| size_ret >= sizeof(buf)) {
d831c249 DG	483	PERROR("read proc failed");
	484	goto error_close;
	485	}
6cd525e8	486	buf[size_ret] = '\0';
d831c249 DG	487
	488	errno = 0;
	489	r_val = strtol(buf, NULL, 10);
	490	if (errno != 0 \|\| r_val < -1L) {
	491	val = 0;
	492	goto error_close;
	493	} else {
	494	if (r_val > 0) {
	495	val = r_val;
	496	}
	497	}
	498
	499	error_close:
	500	ret = close(fd);
	501	if (ret) {
	502	PERROR("close /proc value");
	503	}
	504	error:
	505	return val;
	506	}
	507
d831c249 DG	508	void lttcomm_inet_init(void)
d831c249 DG	509	{
18eed43f DG	510	unsigned long syn_retries, fin_timeout, syn_timeout, env;
	511
	512	env = lttcomm_get_network_timeout();
	513	if (env) {
	514	lttcomm_inet_tcp_timeout = env;
	515	goto end;
	516	}
d831c249 DG	517
	518	/* Assign default value and see if we can change it. */
	519	lttcomm_inet_tcp_timeout = DEFAULT_INET_TCP_TIMEOUT;
	520
	521	syn_retries = read_proc_value(LTTCOMM_INET_PROC_SYN_RETRIES_PATH);
	522	fin_timeout = read_proc_value(LTTCOMM_INET_PROC_FIN_TIMEOUT_PATH);
	523
	524	syn_timeout = syn_retries * LTTCOMM_INET_SYN_TIMEOUT_FACTOR;
	525
	526	/*
	527	* Get the maximum between the two possible timeout value and use that to
	528	* get the maximum with the default timeout.
	529	*/
	530	lttcomm_inet_tcp_timeout = max_t(unsigned long,
	531	max_t(unsigned long, syn_timeout, fin_timeout),
	532	lttcomm_inet_tcp_timeout);
	533
18eed43f	534	end:
d831c249 DG	535	DBG("TCP inet operation timeout set to %lu sec", lttcomm_inet_tcp_timeout);
d831c249 DG	536	}