From: Mathieu Desnoyers Date: Thu, 8 Aug 2013 09:01:53 +0000 (-0400) Subject: Implement timeout for connect ipv4/ipv6 X-Git-Tag: v2.3.0-rc3~53 X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=a655f4cf59f557aef3f0a975988d87bdd3b199fd;p=lttng-tools.git Implement timeout for connect ipv4/ipv6 Signed-off-by: Mathieu Desnoyers Signed-off-by: David Goulet --- diff --git a/src/common/sessiond-comm/Makefile.am b/src/common/sessiond-comm/Makefile.am index 24063f862..72375c0e9 100644 --- a/src/common/sessiond-comm/Makefile.am +++ b/src/common/sessiond-comm/Makefile.am @@ -6,3 +6,4 @@ noinst_LTLIBRARIES = libsessiond-comm.la libsessiond_comm_la_SOURCES = sessiond-comm.c sessiond-comm.h \ unix.c unix.h inet.c inet.h inet6.c inet6.h \ relayd.h +libsessiond_comm_la_LIBADD = -lrt diff --git a/src/common/sessiond-comm/inet.c b/src/common/sessiond-comm/inet.c index b2bd65d90..6d729238a 100644 --- a/src/common/sessiond-comm/inet.c +++ b/src/common/sessiond-comm/inet.c @@ -25,11 +25,18 @@ #include #include #include +#include +#include +#include #include #include "inet.h" +#define MSEC_PER_SEC 1000 +#define NSEC_PER_MSEC 1000000 +#define RECONNECT_DELAY 200 /* ms */ + /* * INET protocol operations. */ @@ -91,6 +98,130 @@ int lttcomm_bind_inet_sock(struct lttcomm_sock *sock) 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. */ @@ -99,8 +230,11 @@ int lttcomm_connect_inet_sock(struct lttcomm_sock *sock) { int ret, closeret; - ret = connect(sock->fd, (struct sockaddr *) &sock->sockaddr.addr.sin, - sizeof(sock->sockaddr.addr.sin)); + if (lttcomm_get_network_timeout()) { + ret = connect_with_timeout(sock); + } else { + ret = connect_no_timeout(sock); + } if (ret < 0) { PERROR("connect"); goto error_connect; diff --git a/src/common/sessiond-comm/inet6.c b/src/common/sessiond-comm/inet6.c index 8d8837404..52e2f8e58 100644 --- a/src/common/sessiond-comm/inet6.c +++ b/src/common/sessiond-comm/inet6.c @@ -25,11 +25,18 @@ #include #include #include +#include +#include +#include #include #include "inet6.h" +#define MSEC_PER_SEC 1000 +#define NSEC_PER_MSEC 1000000 +#define RECONNECT_DELAY 200 /* ms */ + /* * INET protocol operations. */ @@ -91,6 +98,130 @@ int lttcomm_bind_inet6_sock(struct lttcomm_sock *sock) return ret; } +static +int connect_no_timeout(struct lttcomm_sock *sock) +{ + return connect(sock->fd, (struct sockaddr *) &sock->sockaddr.addr.sin6, + sizeof(sock->sockaddr.addr.sin6)); +} + +/* + * 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.sin6, + sizeof(sock->sockaddr.addr.sin6)); + 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. */ @@ -99,8 +230,11 @@ int lttcomm_connect_inet6_sock(struct lttcomm_sock *sock) { int ret, closeret; - ret = connect(sock->fd, (struct sockaddr *) &sock->sockaddr.addr.sin6, - sizeof(sock->sockaddr.addr.sin6)); + if (lttcomm_get_network_timeout()) { + ret = connect_with_timeout(sock); + } else { + ret = connect_no_timeout(sock); + } if (ret < 0) { PERROR("connect inet6"); goto error_connect;