[lttng-tools.git] / liblttng-sessiond-comm / lttng-sessiond-comm.c

/*
 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
 *                      Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; only version 2 of the License.
 * 
 * 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., 59 Temple
 * Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#define _GNU_SOURCE
#include <assert.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/un.h>
#include <unistd.h>
#include <errno.h>

#include <lttng-sessiond-comm.h>

/*
 * Human readable error message.
 */
static const char *lttcomm_readable_code[] = {
	[ LTTCOMM_ERR_INDEX(LTTCOMM_OK) ] = "Success",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_ERR) ] = "Unknown error",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UND) ] = "Undefined command",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_NOT_IMPLEMENTED) ] = "Not implemented",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UNKNOWN_DOMAIN) ] = "Unknown tracing domain",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_SESSION) ] = "No session found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_LIST_FAIL) ] = "Unable to list traceable apps",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_APPS) ] = "No traceable apps found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_SESS_NOT_FOUND) ] = "Session name not found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACE) ] = "No trace found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_FATAL) ] = "Fatal error of the session daemon",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_CREATE_FAIL) ] = "Create trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_START_FAIL) ] = "Start trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_STOP_FAIL) ] = "Stop trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACEABLE) ] = "App is not traceable",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_SELECT_SESS) ] = "A session MUST be selected",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_EXIST_SESS) ] = "Session name already exist",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_CONNECT_FAIL) ] = "Unable to connect to Unix socket",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_APP_NOT_FOUND) ] = "Application not found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_NA) ] = "Kernel tracer not available",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_EVENT_EXIST) ] = "Kernel event already exists",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_SESS_FAIL) ] = "Kernel create session failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_FAIL) ] = "Kernel create channel failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_NOT_FOUND) ] = "Kernel channel not found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_DISABLE_FAIL) ] = "Disable kernel channel failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_ENABLE_FAIL) ] = "Enable kernel channel failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CONTEXT_FAIL) ] = "Add kernel context failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_ENABLE_FAIL) ] = "Enable kernel event failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DISABLE_FAIL) ] = "Disable kernel event failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_META_FAIL) ] = "Opening metadata failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_START_FAIL) ] = "Starting kernel trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_STOP_FAIL) ] = "Stoping kernel trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CONSUMER_FAIL) ] = "Kernel consumer start failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_STREAM_FAIL) ] = "Kernel create stream failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DIR_FAIL) ] = "Kernel trace directory creation failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DIR_EXIST) ] = "Kernel trace directory already exist",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_NO_SESSION) ] = "No kernel session found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_LIST_FAIL) ] = "Listing kernel events failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_SESS_FAIL) ] = "UST create session failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_NOT_FOUND) ] = "UST channel not found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_FAIL) ] = "UST create channel failed",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_COMMAND_SOCK_READY) ] = "consumerd command socket ready",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_SUCCESS_RECV_FD) ] = "consumerd success on receiving fds",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_ERROR_RECV_FD) ] = "consumerd error on receiving fds",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_ERROR) ] = "consumerd error in polling thread",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_NVAL) ] = "consumerd polling on closed fd",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_HUP) ] = "consumerd all fd hung up",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_EXIT_SUCCESS) ] = "consumerd exiting normally",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_EXIT_FAILURE) ] = "consumerd exiting on error",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_OUTFD_ERROR) ] = "consumerd error opening the tracefile",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_EBADF) ] = "consumerd splice EBADF",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_EINVAL) ] = "consumerd splice EINVAL",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_ENOMEM) ] = "consumerd splice ENOMEM",
	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_ESPIPE) ] = "consumerd splice ESPIPE",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_EVENT) ] = "Event not found",
};

/*
 * Return ptr to string representing a human readable error code from the
 * lttcomm_return_code enum.
 *
 * These code MUST be negative in other to treat that as an error value.
 */
const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
{
	int tmp_code = -code;

	if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
		return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
	}

	return "Unknown error code";
}

/*
 * Connect to unix socket using the path name.
 */
int lttcomm_connect_unix_sock(const char *pathname)
{
	struct sockaddr_un sun;
	int fd;
	int ret;

	fd = socket(PF_UNIX, SOCK_STREAM, 0);
	if (fd < 0) {
		perror("socket");
		ret = fd;
		goto error;
	}

	memset(&sun, 0, sizeof(sun));
	sun.sun_family = AF_UNIX;
	strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
	sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';

	ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
	if (ret < 0) {
		/*
		 * Don't print message on connect error, because connect is used in
		 * normal execution to detect if sessiond is alive.
		 */
		goto error_connect;
	}

	return fd;

error_connect:
	close(fd);
error:
	return ret;
}

/*
 * Do an accept(2) on the sock and return the new file descriptor. The socket
 * MUST be bind(2) before.
 */
int lttcomm_accept_unix_sock(int sock)
{
	int new_fd;
	struct sockaddr_un sun;
	socklen_t len = 0;

	/* Blocking call */
	new_fd = accept(sock, (struct sockaddr *) &sun, &len);
	if (new_fd < 0) {
		perror("accept");
		goto error;
	}

	return new_fd;

error:
	return -1;
}

/*
 * Creates a AF_UNIX local socket using pathname bind the socket upon creation
 * and return the fd.
 */
int lttcomm_create_unix_sock(const char *pathname)
{
	struct sockaddr_un sun;
	int fd;
	int ret = -1;

	/* Create server socket */
	if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
		perror("socket");
		goto error;
	}

	memset(&sun, 0, sizeof(sun));
	sun.sun_family = AF_UNIX;
	strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
	sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';

	/* Unlink the old file if present */
	(void) unlink(pathname);
	ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
	if (ret < 0) {
		perror("bind");
		goto error;
	}

	return fd;

error:
	return ret;
}

/*
 * Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
 */
int lttcomm_listen_unix_sock(int sock)
{
	int ret;

	ret = listen(sock, LTTNG_SESSIOND_COMM_MAX_LISTEN);
	if (ret < 0) {
		perror("listen");
	}

	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_recv_unix_sock(int sock, void *buf, size_t len)
{
	struct msghdr msg = { 0 };
	struct iovec iov[1];
	ssize_t ret = -1;

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

	ret = recvmsg(sock, &msg, 0);
	if (ret < 0) {
		perror("recvmsg");
	}

	return ret;
}

/*
 * Send buf data of size len. Using sendmsg API.
 *
 * Return the size of sent data.
 */
ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
{
	struct msghdr msg = { 0 };
	struct iovec iov[1];
	ssize_t ret = -1;

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

	ret = sendmsg(sock, &msg, 0);
	if (ret < 0) {
		perror("sendmsg");
	}

	return ret;
}

/*
 * Shutdown cleanly a unix socket.
 */
int lttcomm_close_unix_sock(int sock)
{
	int ret;

	/* Shutdown receptions and transmissions */
	ret = shutdown(sock, SHUT_RDWR);
	if (ret < 0) {
		perror("shutdown");
	}

	return ret;
}

/*
 * Send a message accompanied by fd(s) over a unix socket.
 *
 * Returns the size of data sent, or negative error value.
 */
ssize_t lttcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd)
{
	struct msghdr msg = { 0 };
	struct cmsghdr *cmptr;
	struct iovec iov[1];
	ssize_t ret = -1;
	unsigned int sizeof_fds = nb_fd * sizeof(int);
	char tmp[CMSG_SPACE(sizeof_fds)];
	char dummy = 0;

	if (nb_fd > LTTCOMM_MAX_SEND_FDS)
		return -EINVAL;

	msg.msg_control = (caddr_t)tmp;
	msg.msg_controllen = CMSG_LEN(sizeof_fds);

	cmptr = CMSG_FIRSTHDR(&msg);
	cmptr->cmsg_level = SOL_SOCKET;
	cmptr->cmsg_type = SCM_RIGHTS;
	cmptr->cmsg_len = CMSG_LEN(sizeof_fds);
	memcpy(CMSG_DATA(cmptr), fds, sizeof_fds);
	/* Sum of the length of all control messages in the buffer: */
	msg.msg_controllen = cmptr->cmsg_len;

	iov[0].iov_base = &dummy;
	iov[0].iov_len = 1;
	msg.msg_iov = iov;
	msg.msg_iovlen = 1;

	ret = sendmsg(sock, &msg, 0);
	if (ret < 0) {
		perror("sendmsg");
	}
	return ret;
}

/*
 * Recv a message accompanied by fd(s) from a unix socket.
 *
 * Returns the size of received data, or negative error value.
 *
 * Expect at most "nb_fd" file descriptors. Returns the number of fd
 * actually received in nb_fd.
 */
ssize_t lttcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd)
{
	struct iovec iov[1];
	ssize_t ret = 0;
	struct cmsghdr *cmsg;
	size_t sizeof_fds = nb_fd * sizeof(int);
	char recv_fd[CMSG_SPACE(sizeof_fds)];
	struct msghdr msg = { 0 };
	char dummy;

	/* Prepare to receive the structures */
	iov[0].iov_base = &dummy;
	iov[0].iov_len = 1;
	msg.msg_iov = iov;
	msg.msg_iovlen = 1;
	msg.msg_control = recv_fd;
	msg.msg_controllen = sizeof(recv_fd);

	ret = recvmsg(sock, &msg, 0);
	if (ret < 0) {
		perror("recvmsg fds");
		goto end;
	}
	if (ret != 1) {
		fprintf(stderr, "Error: Received %zd bytes, expected %d\n",
				ret, 1);
		goto end;
	}
	if (msg.msg_flags & MSG_CTRUNC) {
		fprintf(stderr, "Error: Control message truncated.\n");
		ret = -1;
		goto end;
	}
	cmsg = CMSG_FIRSTHDR(&msg);
	if (!cmsg) {
		fprintf(stderr, "Error: Invalid control message header\n");
		ret = -1;
		goto end;
	}
	if (cmsg->cmsg_level != SOL_SOCKET || cmsg->cmsg_type != SCM_RIGHTS) {
		fprintf(stderr, "Didn't received any fd\n");
		ret = -1;
		goto end;
	}
	if (cmsg->cmsg_len != CMSG_LEN(sizeof_fds)) {
		fprintf(stderr, "Error: Received %zu bytes of ancillary data, expected %zu\n",
				cmsg->cmsg_len, CMSG_LEN(sizeof_fds));
		ret = -1;
		goto end;
	}
	memcpy(fds, CMSG_DATA(cmsg), sizeof_fds);
	ret = sizeof_fds;
end:
	return ret;
}
Commit	Line	Data
826d496d	1	/*
917216f6 DG	2	* Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
917216f6 DG	3	* Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
fac6795d	4	*
917216f6 DG	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of the GNU General Public License as published by the Free
	7	* Software Foundation; only version 2 of the License.
fac6795d	8	*
917216f6 DG	9	* This program is distributed in the hope that it will be useful, but WITHOUT
	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	12	* more details.
fac6795d	13	*
917216f6 DG	14	* You should have received a copy of the GNU General Public License along with
	15	* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
	16	* Place - Suite 330, Boston, MA 02111-1307, USA.
fac6795d DG	17	*/
	18
	19	#define _GNU_SOURCE
1e307fab	20	#include <assert.h>
fac6795d DG	21	#include <limits.h>
	22	#include <stdio.h>
	23	#include <stdlib.h>
	24	#include <string.h>
	25	#include <sys/socket.h>
	26	#include <sys/stat.h>
	27	#include <sys/types.h>
	28	#include <sys/un.h>
	29	#include <unistd.h>
3bd1e081	30	#include <errno.h>
fac6795d	31
e88129fc	32	#include <lttng-sessiond-comm.h>
fac6795d DG	33
	34	/*
	35	* Human readable error message.
	36	*/
	37	static const char *lttcomm_readable_code[] = {
	38	[ LTTCOMM_ERR_INDEX(LTTCOMM_OK) ] = "Success",
	39	[ LTTCOMM_ERR_INDEX(LTTCOMM_ERR) ] = "Unknown error",
	40	[ LTTCOMM_ERR_INDEX(LTTCOMM_UND) ] = "Undefined command",
7d29a247 DG	41	[ LTTCOMM_ERR_INDEX(LTTCOMM_NOT_IMPLEMENTED) ] = "Not implemented",
7d29a247 DG	42	[ LTTCOMM_ERR_INDEX(LTTCOMM_UNKNOWN_DOMAIN) ] = "Unknown tracing domain",
fac6795d DG	43	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_SESSION) ] = "No session found",
fac6795d DG	44	[ LTTCOMM_ERR_INDEX(LTTCOMM_LIST_FAIL) ] = "Unable to list traceable apps",
e065084a	45	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_APPS) ] = "No traceable apps found",
f3ed775e	46	[ LTTCOMM_ERR_INDEX(LTTCOMM_SESS_NOT_FOUND) ] = "Session name not found",
ce3d728c	47	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACE) ] = "No trace found",
ca95a216	48	[ LTTCOMM_ERR_INDEX(LTTCOMM_FATAL) ] = "Fatal error of the session daemon",
df0da139	49	[ LTTCOMM_ERR_INDEX(LTTCOMM_CREATE_FAIL) ] = "Create trace failed",
379473d2	50	[ LTTCOMM_ERR_INDEX(LTTCOMM_START_FAIL) ] = "Start trace failed",
520ff687	51	[ LTTCOMM_ERR_INDEX(LTTCOMM_STOP_FAIL) ] = "Stop trace failed",
379473d2 DG	52	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_TRACEABLE) ] = "App is not traceable",
379473d2 DG	53	[ LTTCOMM_ERR_INDEX(LTTCOMM_SELECT_SESS) ] = "A session MUST be selected",
27673bb6	54	[ LTTCOMM_ERR_INDEX(LTTCOMM_EXIST_SESS) ] = "Session name already exist",
d9800920	55	[ LTTCOMM_ERR_INDEX(LTTCOMM_CONNECT_FAIL) ] = "Unable to connect to Unix socket",
2b0bf864	56	[ LTTCOMM_ERR_INDEX(LTTCOMM_APP_NOT_FOUND) ] = "Application not found",
20fe2104	57	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_NA) ] = "Kernel tracer not available",
7d29a247	58	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_EVENT_EXIST) ] = "Kernel event already exists",
20fe2104 DG	59	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_SESS_FAIL) ] = "Kernel create session failed",
20fe2104 DG	60	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_FAIL) ] = "Kernel create channel failed",
f3ed775e	61	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_NOT_FOUND) ] = "Kernel channel not found",
26cc6b4e	62	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_DISABLE_FAIL) ] = "Disable kernel channel failed",
d36b8583	63	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CHAN_ENABLE_FAIL) ] = "Enable kernel channel failed",
d65106b1	64	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CONTEXT_FAIL) ] = "Add kernel context failed",
f34daff7 DG	65	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_ENABLE_FAIL) ] = "Enable kernel event failed",
f34daff7 DG	66	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DISABLE_FAIL) ] = "Disable kernel event failed",
aaf26714	67	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_META_FAIL) ] = "Opening metadata failed",
8c0faa1d DG	68	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_START_FAIL) ] = "Starting kernel trace failed",
	69	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_STOP_FAIL) ] = "Stoping kernel trace failed",
	70	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_CONSUMER_FAIL) ] = "Kernel consumer start failed",
	71	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_STREAM_FAIL) ] = "Kernel create stream failed",
	72	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DIR_FAIL) ] = "Kernel trace directory creation failed",
	73	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_DIR_EXIST) ] = "Kernel trace directory already exist",
84291629	74	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_NO_SESSION) ] = "No kernel session found",
2ef84c95	75	[ LTTCOMM_ERR_INDEX(LTTCOMM_KERN_LIST_FAIL) ] = "Listing kernel events failed",
0177d773	76	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_SESS_FAIL) ] = "UST create session failed",
2b0bf864 DG	77	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_NOT_FOUND) ] = "UST channel not found",
2b0bf864 DG	78	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_FAIL) ] = "UST create channel failed",
3bd1e081 MD	79	[ LTTCOMM_ERR_INDEX(CONSUMERD_COMMAND_SOCK_READY) ] = "consumerd command socket ready",
	80	[ LTTCOMM_ERR_INDEX(CONSUMERD_SUCCESS_RECV_FD) ] = "consumerd success on receiving fds",
	81	[ LTTCOMM_ERR_INDEX(CONSUMERD_ERROR_RECV_FD) ] = "consumerd error on receiving fds",
	82	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_ERROR) ] = "consumerd error in polling thread",
	83	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_NVAL) ] = "consumerd polling on closed fd",
	84	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_HUP) ] = "consumerd all fd hung up",
	85	[ LTTCOMM_ERR_INDEX(CONSUMERD_EXIT_SUCCESS) ] = "consumerd exiting normally",
	86	[ LTTCOMM_ERR_INDEX(CONSUMERD_EXIT_FAILURE) ] = "consumerd exiting on error",
	87	[ LTTCOMM_ERR_INDEX(CONSUMERD_OUTFD_ERROR) ] = "consumerd error opening the tracefile",
	88	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_EBADF) ] = "consumerd splice EBADF",
	89	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_EINVAL) ] = "consumerd splice EINVAL",
	90	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_ENOMEM) ] = "consumerd splice ENOMEM",
	91	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_ESPIPE) ] = "consumerd splice ESPIPE",
d65106b1	92	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_EVENT) ] = "Event not found",
fac6795d DG	93	};
	94
	95	/*
917216f6 DG	96	* Return ptr to string representing a human readable error code from the
917216f6 DG	97	* lttcomm_return_code enum.
fac6795d	98	*
917216f6	99	* These code MUST be negative in other to treat that as an error value.
fac6795d DG	100	*/
	101	const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
	102	{
	103	int tmp_code = -code;
	104
	105	if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
	106	return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
	107	}
	108
	109	return "Unknown error code";
	110	}
	111
	112	/*
917216f6	113	* Connect to unix socket using the path name.
fac6795d DG	114	*/
	115	int lttcomm_connect_unix_sock(const char *pathname)
	116	{
686204ab MD	117	struct sockaddr_un sun;
686204ab MD	118	int fd;
a8afeb4a	119	int ret;
fac6795d	120
686204ab	121	fd = socket(PF_UNIX, SOCK_STREAM, 0);
fac6795d DG	122	if (fd < 0) {
fac6795d DG	123	perror("socket");
a8afeb4a	124	ret = fd;
fac6795d DG	125	goto error;
	126	}
	127
686204ab MD	128	memset(&sun, 0, sizeof(sun));
	129	sun.sun_family = AF_UNIX;
	130	strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
99497cd0	131	sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';
fac6795d	132
686204ab MD	133	ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
686204ab MD	134	if (ret < 0) {
a8afeb4a	135	/*
917216f6 DG	136	* Don't print message on connect error, because connect is used in
917216f6 DG	137	* normal execution to detect if sessiond is alive.
a8afeb4a MD	138	*/
a8afeb4a MD	139	goto error_connect;
686204ab	140	}
fac6795d	141
686204ab	142	return fd;
fac6795d	143
a8afeb4a MD	144	error_connect:
a8afeb4a MD	145	close(fd);
fac6795d	146	error:
a8afeb4a	147	return ret;
fac6795d DG	148	}
	149
	150	/*
917216f6 DG	151	* Do an accept(2) on the sock and return the new file descriptor. The socket
917216f6 DG	152	* MUST be bind(2) before.
fac6795d DG	153	*/
	154	int lttcomm_accept_unix_sock(int sock)
	155	{
	156	int new_fd;
	157	struct sockaddr_un sun;
	158	socklen_t len = 0;
	159
	160	/* Blocking call */
	161	new_fd = accept(sock, (struct sockaddr *) &sun, &len);
	162	if (new_fd < 0) {
	163	perror("accept");
	164	goto error;
	165	}
	166
	167	return new_fd;
	168
	169	error:
	170	return -1;
	171	}
	172
	173	/*
917216f6 DG	174	* Creates a AF_UNIX local socket using pathname bind the socket upon creation
917216f6 DG	175	* and return the fd.
fac6795d DG	176	*/
	177	int lttcomm_create_unix_sock(const char *pathname)
	178	{
	179	struct sockaddr_un sun;
	180	int fd;
	181	int ret = -1;
	182
	183	/* Create server socket */
	184	if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
	185	perror("socket");
	186	goto error;
	187	}
	188
	189	memset(&sun, 0, sizeof(sun));
	190	sun.sun_family = AF_UNIX;
99497cd0 MD	191	strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
99497cd0 MD	192	sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';
fac6795d	193
7d8234d9 MD	194	/* Unlink the old file if present */
7d8234d9 MD	195	(void) unlink(pathname);
fac6795d DG	196	ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
	197	if (ret < 0) {
	198	perror("bind");
	199	goto error;
	200	}
	201
	202	return fd;
	203
	204	error:
	205	return ret;
	206	}
	207
	208	/*
f158a754	209	* Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
fac6795d DG	210	*/
	211	int lttcomm_listen_unix_sock(int sock)
	212	{
	213	int ret;
	214
f158a754	215	ret = listen(sock, LTTNG_SESSIOND_COMM_MAX_LISTEN);
fac6795d DG	216	if (ret < 0) {
	217	perror("listen");
	218	}
	219
	220	return ret;
	221	}
	222
	223	/*
917216f6 DG	224	* Receive data of size len in put that data into the buf param. Using recvmsg
917216f6 DG	225	* API.
fac6795d	226	*
917216f6	227	* Return the size of received data.
fac6795d DG	228	*/
	229	ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
	230	{
159c7ff4	231	struct msghdr msg = { 0 };
fac6795d DG	232	struct iovec iov[1];
	233	ssize_t ret = -1;
	234
fac6795d DG	235	iov[0].iov_base = buf;
	236	iov[0].iov_len = len;
	237	msg.msg_iov = iov;
	238	msg.msg_iovlen = 1;
	239
	240	ret = recvmsg(sock, &msg, 0);
	241	if (ret < 0) {
	242	perror("recvmsg");
	243	}
	244
	245	return ret;
	246	}
	247
	248	/*
917216f6	249	* Send buf data of size len. Using sendmsg API.
fac6795d	250	*
917216f6	251	* Return the size of sent data.
fac6795d DG	252	*/
	253	ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
	254	{
159c7ff4	255	struct msghdr msg = { 0 };
fac6795d DG	256	struct iovec iov[1];
	257	ssize_t ret = -1;
	258
fac6795d DG	259	iov[0].iov_base = buf;
	260	iov[0].iov_len = len;
	261	msg.msg_iov = iov;
	262	msg.msg_iovlen = 1;
	263
	264	ret = sendmsg(sock, &msg, 0);
	265	if (ret < 0) {
	266	perror("sendmsg");
	267	}
	268
	269	return ret;
	270	}
87378cf5 DG	271
87378cf5 DG	272	/*
917216f6	273	* Shutdown cleanly a unix socket.
87378cf5 DG	274	*/
	275	int lttcomm_close_unix_sock(int sock)
	276	{
	277	int ret;
	278
	279	/* Shutdown receptions and transmissions */
	280	ret = shutdown(sock, SHUT_RDWR);
	281	if (ret < 0) {
	282	perror("shutdown");
	283	}
	284
	285	return ret;
	286	}
8c0faa1d DG	287
8c0faa1d DG	288	/*
3bd1e081 MD	289	* Send a message accompanied by fd(s) over a unix socket.
	290	*
	291	* Returns the size of data sent, or negative error value.
8c0faa1d	292	*/
3bd1e081	293	ssize_t lttcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd)
8c0faa1d	294	{
159c7ff4	295	struct msghdr msg = { 0 };
8c0faa1d DG	296	struct cmsghdr *cmptr;
	297	struct iovec iov[1];
	298	ssize_t ret = -1;
	299	unsigned int sizeof_fds = nb_fd * sizeof(int);
	300	char tmp[CMSG_SPACE(sizeof_fds)];
3bd1e081	301	char dummy = 0;
8c0faa1d	302
3bd1e081 MD	303	if (nb_fd > LTTCOMM_MAX_SEND_FDS)
3bd1e081 MD	304	return -EINVAL;
8c0faa1d DG	305
	306	msg.msg_control = (caddr_t)tmp;
	307	msg.msg_controllen = CMSG_LEN(sizeof_fds);
	308
	309	cmptr = CMSG_FIRSTHDR(&msg);
8c0faa1d DG	310	cmptr->cmsg_level = SOL_SOCKET;
8c0faa1d DG	311	cmptr->cmsg_type = SCM_RIGHTS;
159c7ff4	312	cmptr->cmsg_len = CMSG_LEN(sizeof_fds);
8c0faa1d	313	memcpy(CMSG_DATA(cmptr), fds, sizeof_fds);
159c7ff4 MD	314	/* Sum of the length of all control messages in the buffer: */
159c7ff4 MD	315	msg.msg_controllen = cmptr->cmsg_len;
8c0faa1d	316
3bd1e081 MD	317	iov[0].iov_base = &dummy;
3bd1e081 MD	318	iov[0].iov_len = 1;
8c0faa1d DG	319	msg.msg_iov = iov;
	320	msg.msg_iovlen = 1;
	321
	322	ret = sendmsg(sock, &msg, 0);
	323	if (ret < 0) {
	324	perror("sendmsg");
	325	}
8c0faa1d DG	326	return ret;
8c0faa1d DG	327	}
09de5c68 DG	328
09de5c68 DG	329	/*
3bd1e081	330	* Recv a message accompanied by fd(s) from a unix socket.
09de5c68	331	*
3bd1e081 MD	332	* Returns the size of received data, or negative error value.
	333	*
	334	* Expect at most "nb_fd" file descriptors. Returns the number of fd
	335	* actually received in nb_fd.
09de5c68	336	*/
3bd1e081	337	ssize_t lttcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd)
09de5c68 DG	338	{
09de5c68 DG	339	struct iovec iov[1];
3bd1e081	340	ssize_t ret = 0;
09de5c68	341	struct cmsghdr *cmsg;
3bd1e081 MD	342	size_t sizeof_fds = nb_fd * sizeof(int);
3bd1e081 MD	343	char recv_fd[CMSG_SPACE(sizeof_fds)];
09de5c68	344	struct msghdr msg = { 0 };
3bd1e081	345	char dummy;
09de5c68 DG	346
09de5c68 DG	347	/* Prepare to receive the structures */
3bd1e081 MD	348	iov[0].iov_base = &dummy;
3bd1e081 MD	349	iov[0].iov_len = 1;
09de5c68 DG	350	msg.msg_iov = iov;
	351	msg.msg_iovlen = 1;
	352	msg.msg_control = recv_fd;
	353	msg.msg_controllen = sizeof(recv_fd);
	354
	355	ret = recvmsg(sock, &msg, 0);
	356	if (ret < 0) {
	357	perror("recvmsg fds");
	358	goto end;
	359	}
3bd1e081 MD	360	if (ret != 1) {
	361	fprintf(stderr, "Error: Received %zd bytes, expected %d\n",
	362	ret, 1);
	363	goto end;
	364	}
	365	if (msg.msg_flags & MSG_CTRUNC) {
	366	fprintf(stderr, "Error: Control message truncated.\n");
	367	ret = -1;
09de5c68 DG	368	goto end;
09de5c68 DG	369	}
09de5c68 DG	370	cmsg = CMSG_FIRSTHDR(&msg);
09de5c68 DG	371	if (!cmsg) {
3bd1e081	372	fprintf(stderr, "Error: Invalid control message header\n");
09de5c68 DG	373	ret = -1;
	374	goto end;
	375	}
09de5c68	376	if (cmsg->cmsg_level != SOL_SOCKET \|\| cmsg->cmsg_type != SCM_RIGHTS) {
3bd1e081	377	fprintf(stderr, "Didn't received any fd\n");
09de5c68 DG	378	ret = -1;
	379	goto end;
	380	}
3bd1e081 MD	381	if (cmsg->cmsg_len != CMSG_LEN(sizeof_fds)) {
	382	fprintf(stderr, "Error: Received %zu bytes of ancillary data, expected %zu\n",
	383	cmsg->cmsg_len, CMSG_LEN(sizeof_fds));
	384	ret = -1;
	385	goto end;
09de5c68	386	}
3bd1e081 MD	387	memcpy(fds, CMSG_DATA(cmsg), sizeof_fds);
3bd1e081 MD	388	ret = sizeof_fds;
09de5c68 DG	389	end:
	390	return ret;
	391	}