[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_FAIL) ] = "UST create channel failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_NOT_FOUND) ] = "UST channel not found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_DISABLE_FAIL) ] = "Disable UST channel failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_ENABLE_FAIL) ] = "Enable UST channel failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CONTEXT_FAIL) ] = "Add UST context failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_ENABLE_FAIL) ] = "Enable UST event failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_DISABLE_FAIL) ] = "Disable UST event failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_META_FAIL) ] = "Opening metadata failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_START_FAIL) ] = "Starting UST trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_STOP_FAIL) ] = "Stoping UST trace failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CONSUMER_FAIL) ] = "UST consumer start failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_STREAM_FAIL) ] = "UST create stream failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_DIR_FAIL) ] = "UST trace directory creation failed",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_DIR_EXIST) ] = "UST trace directory already exist",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_NO_SESSION) ] = "No UST session found",
	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_LIST_FAIL) ] = "Listing UST events 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_ERROR_RECV_CMD) ] = "consumerd error on receiving command",
	[ 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	77	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_FAIL) ] = "UST create channel failed",
2bdd86d4 MD	78	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_NOT_FOUND) ] = "UST channel not found",
	79	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_DISABLE_FAIL) ] = "Disable UST channel failed",
	80	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CHAN_ENABLE_FAIL) ] = "Enable UST channel failed",
	81	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CONTEXT_FAIL) ] = "Add UST context failed",
	82	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_ENABLE_FAIL) ] = "Enable UST event failed",
	83	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_DISABLE_FAIL) ] = "Disable UST event failed",
	84	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_META_FAIL) ] = "Opening metadata failed",
	85	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_START_FAIL) ] = "Starting UST trace failed",
	86	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_STOP_FAIL) ] = "Stoping UST trace failed",
	87	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_CONSUMER_FAIL) ] = "UST consumer start failed",
	88	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_STREAM_FAIL) ] = "UST create stream failed",
	89	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_DIR_FAIL) ] = "UST trace directory creation failed",
	90	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_DIR_EXIST) ] = "UST trace directory already exist",
	91	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_NO_SESSION) ] = "No UST session found",
	92	[ LTTCOMM_ERR_INDEX(LTTCOMM_UST_LIST_FAIL) ] = "Listing UST events failed",
3bd1e081 MD	93	[ LTTCOMM_ERR_INDEX(CONSUMERD_COMMAND_SOCK_READY) ] = "consumerd command socket ready",
	94	[ LTTCOMM_ERR_INDEX(CONSUMERD_SUCCESS_RECV_FD) ] = "consumerd success on receiving fds",
	95	[ LTTCOMM_ERR_INDEX(CONSUMERD_ERROR_RECV_FD) ] = "consumerd error on receiving fds",
f2fc6720	96	[ LTTCOMM_ERR_INDEX(CONSUMERD_ERROR_RECV_CMD) ] = "consumerd error on receiving command",
3bd1e081 MD	97	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_ERROR) ] = "consumerd error in polling thread",
	98	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_NVAL) ] = "consumerd polling on closed fd",
	99	[ LTTCOMM_ERR_INDEX(CONSUMERD_POLL_HUP) ] = "consumerd all fd hung up",
	100	[ LTTCOMM_ERR_INDEX(CONSUMERD_EXIT_SUCCESS) ] = "consumerd exiting normally",
	101	[ LTTCOMM_ERR_INDEX(CONSUMERD_EXIT_FAILURE) ] = "consumerd exiting on error",
	102	[ LTTCOMM_ERR_INDEX(CONSUMERD_OUTFD_ERROR) ] = "consumerd error opening the tracefile",
	103	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_EBADF) ] = "consumerd splice EBADF",
	104	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_EINVAL) ] = "consumerd splice EINVAL",
	105	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_ENOMEM) ] = "consumerd splice ENOMEM",
	106	[ LTTCOMM_ERR_INDEX(CONSUMERD_SPLICE_ESPIPE) ] = "consumerd splice ESPIPE",
d65106b1	107	[ LTTCOMM_ERR_INDEX(LTTCOMM_NO_EVENT) ] = "Event not found",
fac6795d DG	108	};
	109
	110	/*
917216f6 DG	111	* Return ptr to string representing a human readable error code from the
917216f6 DG	112	* lttcomm_return_code enum.
fac6795d	113	*
917216f6	114	* These code MUST be negative in other to treat that as an error value.
fac6795d DG	115	*/
	116	const char *lttcomm_get_readable_code(enum lttcomm_return_code code)
	117	{
	118	int tmp_code = -code;
	119
	120	if (tmp_code >= LTTCOMM_OK && tmp_code < LTTCOMM_NR) {
	121	return lttcomm_readable_code[LTTCOMM_ERR_INDEX(tmp_code)];
	122	}
	123
	124	return "Unknown error code";
	125	}
	126
	127	/*
917216f6	128	* Connect to unix socket using the path name.
fac6795d DG	129	*/
	130	int lttcomm_connect_unix_sock(const char *pathname)
	131	{
686204ab MD	132	struct sockaddr_un sun;
686204ab MD	133	int fd;
a8afeb4a	134	int ret;
fac6795d	135
686204ab	136	fd = socket(PF_UNIX, SOCK_STREAM, 0);
fac6795d DG	137	if (fd < 0) {
fac6795d DG	138	perror("socket");
a8afeb4a	139	ret = fd;
fac6795d DG	140	goto error;
	141	}
	142
686204ab MD	143	memset(&sun, 0, sizeof(sun));
	144	sun.sun_family = AF_UNIX;
	145	strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
99497cd0	146	sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';
fac6795d	147
686204ab MD	148	ret = connect(fd, (struct sockaddr *) &sun, sizeof(sun));
686204ab MD	149	if (ret < 0) {
a8afeb4a	150	/*
917216f6 DG	151	* Don't print message on connect error, because connect is used in
917216f6 DG	152	* normal execution to detect if sessiond is alive.
a8afeb4a MD	153	*/
a8afeb4a MD	154	goto error_connect;
686204ab	155	}
fac6795d	156
686204ab	157	return fd;
fac6795d	158
a8afeb4a MD	159	error_connect:
a8afeb4a MD	160	close(fd);
fac6795d	161	error:
a8afeb4a	162	return ret;
fac6795d DG	163	}
	164
	165	/*
917216f6 DG	166	* Do an accept(2) on the sock and return the new file descriptor. The socket
917216f6 DG	167	* MUST be bind(2) before.
fac6795d DG	168	*/
	169	int lttcomm_accept_unix_sock(int sock)
	170	{
	171	int new_fd;
	172	struct sockaddr_un sun;
	173	socklen_t len = 0;
	174
	175	/* Blocking call */
	176	new_fd = accept(sock, (struct sockaddr *) &sun, &len);
	177	if (new_fd < 0) {
	178	perror("accept");
	179	goto error;
	180	}
	181
	182	return new_fd;
	183
	184	error:
	185	return -1;
	186	}
	187
	188	/*
917216f6 DG	189	* Creates a AF_UNIX local socket using pathname bind the socket upon creation
917216f6 DG	190	* and return the fd.
fac6795d DG	191	*/
	192	int lttcomm_create_unix_sock(const char *pathname)
	193	{
	194	struct sockaddr_un sun;
	195	int fd;
	196	int ret = -1;
	197
	198	/* Create server socket */
	199	if ((fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) {
	200	perror("socket");
	201	goto error;
	202	}
	203
	204	memset(&sun, 0, sizeof(sun));
	205	sun.sun_family = AF_UNIX;
99497cd0 MD	206	strncpy(sun.sun_path, pathname, sizeof(sun.sun_path));
99497cd0 MD	207	sun.sun_path[sizeof(sun.sun_path) - 1] = '\0';
fac6795d	208
7d8234d9 MD	209	/* Unlink the old file if present */
7d8234d9 MD	210	(void) unlink(pathname);
fac6795d DG	211	ret = bind(fd, (struct sockaddr *) &sun, sizeof(sun));
	212	if (ret < 0) {
	213	perror("bind");
	214	goto error;
	215	}
	216
	217	return fd;
	218
	219	error:
	220	return ret;
	221	}
	222
	223	/*
f158a754	224	* Make the socket listen using LTTNG_SESSIOND_COMM_MAX_LISTEN.
fac6795d DG	225	*/
	226	int lttcomm_listen_unix_sock(int sock)
	227	{
	228	int ret;
	229
f158a754	230	ret = listen(sock, LTTNG_SESSIOND_COMM_MAX_LISTEN);
fac6795d DG	231	if (ret < 0) {
	232	perror("listen");
	233	}
	234
	235	return ret;
	236	}
	237
	238	/*
917216f6 DG	239	* Receive data of size len in put that data into the buf param. Using recvmsg
917216f6 DG	240	* API.
fac6795d	241	*
917216f6	242	* Return the size of received data.
fac6795d DG	243	*/
	244	ssize_t lttcomm_recv_unix_sock(int sock, void *buf, size_t len)
	245	{
159c7ff4	246	struct msghdr msg = { 0 };
fac6795d DG	247	struct iovec iov[1];
	248	ssize_t ret = -1;
	249
fac6795d DG	250	iov[0].iov_base = buf;
	251	iov[0].iov_len = len;
	252	msg.msg_iov = iov;
	253	msg.msg_iovlen = 1;
	254
	255	ret = recvmsg(sock, &msg, 0);
	256	if (ret < 0) {
	257	perror("recvmsg");
	258	}
	259
	260	return ret;
	261	}
	262
	263	/*
917216f6	264	* Send buf data of size len. Using sendmsg API.
fac6795d	265	*
917216f6	266	* Return the size of sent data.
fac6795d DG	267	*/
	268	ssize_t lttcomm_send_unix_sock(int sock, void *buf, size_t len)
	269	{
159c7ff4	270	struct msghdr msg = { 0 };
fac6795d DG	271	struct iovec iov[1];
	272	ssize_t ret = -1;
	273
fac6795d DG	274	iov[0].iov_base = buf;
	275	iov[0].iov_len = len;
	276	msg.msg_iov = iov;
	277	msg.msg_iovlen = 1;
	278
	279	ret = sendmsg(sock, &msg, 0);
	280	if (ret < 0) {
	281	perror("sendmsg");
	282	}
	283
	284	return ret;
	285	}
87378cf5 DG	286
87378cf5 DG	287	/*
917216f6	288	* Shutdown cleanly a unix socket.
87378cf5 DG	289	*/
	290	int lttcomm_close_unix_sock(int sock)
	291	{
	292	int ret;
	293
	294	/* Shutdown receptions and transmissions */
	295	ret = shutdown(sock, SHUT_RDWR);
	296	if (ret < 0) {
	297	perror("shutdown");
	298	}
	299
	300	return ret;
	301	}
8c0faa1d DG	302
8c0faa1d DG	303	/*
3bd1e081 MD	304	* Send a message accompanied by fd(s) over a unix socket.
	305	*
	306	* Returns the size of data sent, or negative error value.
8c0faa1d	307	*/
3bd1e081	308	ssize_t lttcomm_send_fds_unix_sock(int sock, int *fds, size_t nb_fd)
8c0faa1d	309	{
159c7ff4	310	struct msghdr msg = { 0 };
8c0faa1d DG	311	struct cmsghdr *cmptr;
	312	struct iovec iov[1];
	313	ssize_t ret = -1;
	314	unsigned int sizeof_fds = nb_fd * sizeof(int);
	315	char tmp[CMSG_SPACE(sizeof_fds)];
3bd1e081	316	char dummy = 0;
8c0faa1d	317
3bd1e081 MD	318	if (nb_fd > LTTCOMM_MAX_SEND_FDS)
3bd1e081 MD	319	return -EINVAL;
8c0faa1d DG	320
	321	msg.msg_control = (caddr_t)tmp;
	322	msg.msg_controllen = CMSG_LEN(sizeof_fds);
	323
	324	cmptr = CMSG_FIRSTHDR(&msg);
8c0faa1d DG	325	cmptr->cmsg_level = SOL_SOCKET;
8c0faa1d DG	326	cmptr->cmsg_type = SCM_RIGHTS;
159c7ff4	327	cmptr->cmsg_len = CMSG_LEN(sizeof_fds);
8c0faa1d	328	memcpy(CMSG_DATA(cmptr), fds, sizeof_fds);
159c7ff4 MD	329	/* Sum of the length of all control messages in the buffer: */
159c7ff4 MD	330	msg.msg_controllen = cmptr->cmsg_len;
8c0faa1d	331
3bd1e081 MD	332	iov[0].iov_base = &dummy;
3bd1e081 MD	333	iov[0].iov_len = 1;
8c0faa1d DG	334	msg.msg_iov = iov;
	335	msg.msg_iovlen = 1;
	336
	337	ret = sendmsg(sock, &msg, 0);
	338	if (ret < 0) {
	339	perror("sendmsg");
	340	}
8c0faa1d DG	341	return ret;
8c0faa1d DG	342	}
09de5c68 DG	343
09de5c68 DG	344	/*
3bd1e081	345	* Recv a message accompanied by fd(s) from a unix socket.
09de5c68	346	*
3bd1e081 MD	347	* Returns the size of received data, or negative error value.
	348	*
	349	* Expect at most "nb_fd" file descriptors. Returns the number of fd
	350	* actually received in nb_fd.
09de5c68	351	*/
3bd1e081	352	ssize_t lttcomm_recv_fds_unix_sock(int sock, int *fds, size_t nb_fd)
09de5c68 DG	353	{
09de5c68 DG	354	struct iovec iov[1];
3bd1e081	355	ssize_t ret = 0;
09de5c68	356	struct cmsghdr *cmsg;
3bd1e081 MD	357	size_t sizeof_fds = nb_fd * sizeof(int);
3bd1e081 MD	358	char recv_fd[CMSG_SPACE(sizeof_fds)];
09de5c68	359	struct msghdr msg = { 0 };
3bd1e081	360	char dummy;
09de5c68 DG	361
09de5c68 DG	362	/* Prepare to receive the structures */
3bd1e081 MD	363	iov[0].iov_base = &dummy;
3bd1e081 MD	364	iov[0].iov_len = 1;
09de5c68 DG	365	msg.msg_iov = iov;
	366	msg.msg_iovlen = 1;
	367	msg.msg_control = recv_fd;
	368	msg.msg_controllen = sizeof(recv_fd);
	369
	370	ret = recvmsg(sock, &msg, 0);
	371	if (ret < 0) {
	372	perror("recvmsg fds");
	373	goto end;
	374	}
3bd1e081 MD	375	if (ret != 1) {
	376	fprintf(stderr, "Error: Received %zd bytes, expected %d\n",
	377	ret, 1);
	378	goto end;
	379	}
	380	if (msg.msg_flags & MSG_CTRUNC) {
	381	fprintf(stderr, "Error: Control message truncated.\n");
	382	ret = -1;
09de5c68 DG	383	goto end;
09de5c68 DG	384	}
09de5c68 DG	385	cmsg = CMSG_FIRSTHDR(&msg);
09de5c68 DG	386	if (!cmsg) {
3bd1e081	387	fprintf(stderr, "Error: Invalid control message header\n");
09de5c68 DG	388	ret = -1;
	389	goto end;
	390	}
09de5c68	391	if (cmsg->cmsg_level != SOL_SOCKET \|\| cmsg->cmsg_type != SCM_RIGHTS) {
3bd1e081	392	fprintf(stderr, "Didn't received any fd\n");
09de5c68 DG	393	ret = -1;
	394	goto end;
	395	}
3bd1e081 MD	396	if (cmsg->cmsg_len != CMSG_LEN(sizeof_fds)) {
	397	fprintf(stderr, "Error: Received %zu bytes of ancillary data, expected %zu\n",
	398	cmsg->cmsg_len, CMSG_LEN(sizeof_fds));
	399	ret = -1;
	400	goto end;
09de5c68	401	}
3bd1e081 MD	402	memcpy(fds, CMSG_DATA(cmsg), sizeof_fds);
3bd1e081 MD	403	ret = sizeof_fds;
09de5c68 DG	404	end:
	405	return ret;
	406	}