X-Git-Url: http://git.efficios.com/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Flib%2Flttng-ctl%2Fchannel.c;h=f2a65885d74416c08885ffe7ebcf5793f683fb09;hp=5271aa13fbd76218fca47b8984c6a055fc84b35f;hb=25357057de5ae4dd2a572e8f9b893c1b90cbd60a;hpb=a57a7f22e21b8b5dbb32e6b0096c81e869543aa2 diff --git a/src/lib/lttng-ctl/channel.c b/src/lib/lttng-ctl/channel.c index 5271aa13f..f2a65885d 100644 --- a/src/lib/lttng-ctl/channel.c +++ b/src/lib/lttng-ctl/channel.c @@ -1,18 +1,8 @@ /* - * Copyright (C) 2017 - Jérémie Galarneau + * Copyright (C) 2017 Jérémie Galarneau * - * This library is free software; you can redistribute it and/or modify it - * under the terms of the GNU Lesser General Public License, version 2.1 only, - * as published by the Free Software Foundation. + * SPDX-License-Identifier: LGPL-2.1-only * - * This library 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 Lesser General Public License - * for more details. - * - * You should have received a copy of the GNU Lesser General Public License - * along with this library; if not, write to the Free Software Foundation, - * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include @@ -26,8 +16,7 @@ #include #include #include "lttng-ctl-helper.h" -#include -#include +#include static int handshake(struct lttng_notification_channel *channel); @@ -211,7 +200,7 @@ lttng_notification_channel_get_next_notification( struct lttng_notification *notification = NULL; enum lttng_notification_channel_status status = LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; - fd_set read_fds; + struct lttng_poll_event events; if (!channel || !_notification) { status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; @@ -241,9 +230,9 @@ lttng_notification_channel_get_next_notification( } /* - * Block on select() instead of the message reception itself as the - * recvmsg() wrappers always restard on EINTR. We choose to wait - * using select() in order to: + * Block on interruptible epoll/poll() instead of the message reception + * itself as the recvmsg() wrappers always restart on EINTR. We choose + * to wait using interruptible epoll/poll() in order to: * 1) Return if a signal occurs, * 2) Not deal with partially received messages. * @@ -252,20 +241,28 @@ lttng_notification_channel_get_next_notification( * announced length, receive_message() will block on recvmsg() * and never return (even if a signal is received). */ - FD_ZERO(&read_fds); - FD_SET(channel->socket, &read_fds); - ret = select(channel->socket + 1, &read_fds, NULL, NULL, NULL); - if (ret == -1) { - status = errno == EINTR ? + ret = lttng_poll_create(&events, 1, LTTNG_CLOEXEC); + if (ret < 0) { + status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; + goto end_unlock; + } + ret = lttng_poll_add(&events, channel->socket, LPOLLIN | LPOLLERR); + if (ret < 0) { + status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; + goto end_clean_poll; + } + ret = lttng_poll_wait_interruptible(&events, -1); + if (ret <= 0) { + status = (ret == -1 && errno == EINTR) ? LTTNG_NOTIFICATION_CHANNEL_STATUS_INTERRUPTED : LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } ret = receive_message(channel); if (ret) { status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } switch (get_current_message_type(channel)) { @@ -274,7 +271,7 @@ lttng_notification_channel_get_next_notification( channel); if (!notification) { status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } break; case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED: @@ -284,9 +281,11 @@ lttng_notification_channel_get_next_notification( default: /* Protocol error. */ status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } +end_clean_poll: + lttng_poll_clean(&events); end_unlock: pthread_mutex_unlock(&channel->lock); *_notification = notification; @@ -387,11 +386,7 @@ lttng_notification_channel_has_pending_notification( int ret; enum lttng_notification_channel_status status = LTTNG_NOTIFICATION_CHANNEL_STATUS_OK; - fd_set read_fds; - struct timeval timeout; - - FD_ZERO(&read_fds); - memset(&timeout, 0, sizeof(timeout)); + struct lttng_poll_event events; if (!channel || !_notification_pending) { status = LTTNG_NOTIFICATION_CHANNEL_STATUS_INVALID; @@ -426,48 +421,57 @@ lttng_notification_channel_has_pending_notification( * message if we see data available on the socket. If the peer does * not respect the protocol, this may block indefinitely. */ - FD_SET(channel->socket, &read_fds); - do { - ret = select(channel->socket + 1, &read_fds, NULL, NULL, &timeout); - } while (ret < 0 && errno == EINTR); - + ret = lttng_poll_create(&events, 1, LTTNG_CLOEXEC); + if (ret < 0) { + status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; + goto end_unlock; + } + ret = lttng_poll_add(&events, channel->socket, LPOLLIN | LPOLLERR); + if (ret < 0) { + status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; + goto end_clean_poll; + } + /* timeout = 0: return immediately. */ + ret = lttng_poll_wait_interruptible(&events, 0); if (ret == 0) { /* No data available. */ *_notification_pending = false; - goto end_unlock; + goto end_clean_poll; } else if (ret < 0) { status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } /* Data available on socket. */ ret = receive_message(channel); if (ret) { status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } switch (get_current_message_type(channel)) { case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION: ret = enqueue_notification_from_current_message(channel); if (ret) { - goto end_unlock; + goto end_clean_poll; } *_notification_pending = true; break; case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED: ret = enqueue_dropped_notification(channel); if (ret) { - goto end_unlock; + goto end_clean_poll; } *_notification_pending = true; break; default: /* Protocol error. */ status = LTTNG_NOTIFICATION_CHANNEL_STATUS_ERROR; - goto end_unlock; + goto end_clean_poll; } +end_clean_poll: + lttng_poll_clean(&events); end_unlock: pthread_mutex_unlock(&channel->lock); end: