X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=src%2Ffrontend%2Fsock.c;h=414c90775657294c0408ffb1e8c1eaea78ae8f0d;hb=40bc8e8e47d2e171fd0fafe1eeecd2a0241cd33c;hp=a389a142b94f8a1a609a02a2ae1773239dc0e624;hpb=635debdd1d9f4b4982cdff91fcb244b64ea341fc;p=sysdb.git

diff --git a/src/frontend/sock.c b/src/frontend/sock.c
index a389a14..414c907 100644
--- a/src/frontend/sock.c
+++ b/src/frontend/sock.c
@@ -92,6 +92,10 @@ struct sdb_fe_socket {
 	size_t listeners_num;
 
 	sdb_llist_t *open_connections;
+
+	/* channel used for communication between main
+	 * and connection handler threads */
+	sdb_channel_t *chan;
 };
 
 /*
@@ -177,6 +181,7 @@ listener_destroy(listener_t *listener)
 
 	if (listener->sock_fd >= 0)
 		close(listener->sock_fd);
+	listener->sock_fd = -1;
 
 	if (listener->address)
 		free(listener->address);
@@ -228,6 +233,48 @@ listener_create(sdb_fe_socket_t *sock, const char *address)
 	return listener;
 } /* listener_create */
 
+static int
+listener_listen(listener_t *listener)
+{
+	assert(listener);
+
+	/* try to reopen */
+	if (listener->sock_fd < 0)
+		if (listener_impls[listener->type].opener(listener))
+			return -1;
+	assert(listener->sock_fd >= 0);
+
+	if (listen(listener->sock_fd, /* backlog = */ 32)) {
+		char buf[1024];
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to listen on socket %s: %s",
+				listener->address, sdb_strerror(errno, buf, sizeof(buf)));
+		return -1;
+	}
+	return 0;
+} /* listener_listen */
+
+static void
+listener_close(listener_t *listener)
+{
+	assert(listener);
+
+	if (listener->sock_fd < 0)
+		return;
+
+	close(listener->sock_fd);
+	listener->sock_fd = -1;
+} /* listener_close */
+
+static void
+socket_close(sdb_fe_socket_t *sock)
+{
+	size_t i;
+
+	assert(sock);
+	for (i = 0; i < sock->listeners_num; ++i)
+		listener_close(sock->listeners + i);
+} /* socket_close */
+
 /*
  * private data types
  */
@@ -288,6 +335,7 @@ connection_destroy(sdb_object_t *obj)
 	assert(obj);
 	conn = &CONN(obj)->conn;
 
+	sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection on fd=%i", conn->fd);
 	close(conn->fd);
 	conn->fd = -1;
 } /* connection_destroy */
@@ -302,12 +350,41 @@ static sdb_type_t connection_type = {
  * connection handler functions
  */
 
+/* returns negative value on error, 0 on EOF, number of packets else */
+static int
+connection_read(int fd)
+{
+	int n = 0;
+
+	while (42) {
+		int32_t cmd;
+		ssize_t status;
+
+		errno = 0;
+		status = read(fd, &cmd, sizeof(cmd));
+		if (status < 0) {
+			if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
+				return n + 1;
+			return (int)status;
+		}
+		else if (! status) /* EOF */
+			return 0;
+
+		/* XXX */
+		sdb_log(SDB_LOG_DEBUG, "frontend: read command %i from fd=%i",
+				cmd, fd);
+		++n;
+	}
+
+	return n + 1;
+} /* connection_read */
+
 static void *
 connection_handler(void *data)
 {
-	sdb_channel_t *chan = data;
+	sdb_fe_socket_t *sock = data;
 
-	assert(chan);
+	assert(sock);
 
 	while (42) {
 		struct timespec timeout = { 0, 500000000 }; /* .5 seconds */
@@ -315,7 +392,8 @@ connection_handler(void *data)
 		int status;
 
 		errno = 0;
-		status = sdb_channel_select(chan, NULL, &conn, NULL, NULL, &timeout);
+		status = sdb_channel_select(sock->chan, /* read */ NULL, &conn,
+				/* write */ NULL, NULL, &timeout);
 		if (status) {
 			char buf[1024];
 
@@ -329,20 +407,32 @@ connection_handler(void *data)
 			continue;
 		}
 
-		/* XXX */
-		sdb_log(SDB_LOG_INFO, "frontend: Data available on connection fd=%i\n",
-				conn->conn.fd);
+		status = connection_read(conn->conn.fd);
+		if (status <= 0) {
+			/* error or EOF -> close connection */
+			sdb_object_deref(SDB_OBJ(conn));
+		}
+		else {
+			if (sdb_llist_append(sock->open_connections, SDB_OBJ(conn))) {
+				sdb_log(SDB_LOG_ERR, "frontend: Failed to re-append "
+						"connection %s to list of open connections",
+						SDB_OBJ(conn)->name);
+			}
+
+			/* pass ownership back to list; or destroy in case of an error */
+			sdb_object_deref(SDB_OBJ(conn));
+		}
 	}
 	return NULL;
 } /* connection_handler */
 
 static int
-accept_connection(sdb_fe_socket_t *sock, listener_t *listener)
+connection_accept(sdb_fe_socket_t *sock, listener_t *listener)
 {
 	sdb_object_t *obj;
 
-	/* the X's will be replaced with the accepted file descriptor
-	 * when initializing the object */
+	/* the placeholder will be replaced with the accepted file
+	 * descriptor when initializing the object */
 	obj = sdb_object_create(CONN_FD_PREFIX CONN_FD_PLACEHOLDER,
 			connection_type, listener->sock_fd);
 	if (! obj)
@@ -359,7 +449,44 @@ accept_connection(sdb_fe_socket_t *sock, listener_t *listener)
 	/* hand ownership over to the list */
 	sdb_object_deref(obj);
 	return 0;
-} /* accept_connection */
+} /* connection_accept */
+
+static int
+socket_handle_incoming(sdb_fe_socket_t *sock,
+		fd_set *ready, fd_set *exceptions)
+{
+	sdb_llist_iter_t *iter;
+	size_t i;
+
+	for (i = 0; i < sock->listeners_num; ++i) {
+		listener_t *listener = sock->listeners + i;
+		if (FD_ISSET(listener->sock_fd, ready))
+			if (connection_accept(sock, listener))
+				continue;
+	}
+
+	iter = sdb_llist_get_iter(sock->open_connections);
+	if (! iter) {
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to acquire iterator "
+				"for open connections");
+		return -1;
+	}
+
+	while (sdb_llist_iter_has_next(iter)) {
+		sdb_object_t *obj = sdb_llist_iter_get_next(iter);
+
+		if (FD_ISSET(CONN(obj)->conn.fd, exceptions))
+			sdb_log(SDB_LOG_INFO, "Exception on fd %d",
+					CONN(obj)->conn.fd);
+
+		if (FD_ISSET(CONN(obj)->conn.fd, ready)) {
+			sdb_llist_iter_remove_current(iter);
+			sdb_channel_write(sock->chan, &obj);
+		}
+	}
+	sdb_llist_iter_destroy(iter);
+	return 0;
+} /* socket_handle_incoming */
 
 /*
  * public API
@@ -419,7 +546,6 @@ sdb_fe_sock_add_listener(sdb_fe_socket_t *sock, const char *address)
 int
 sdb_fe_sock_listen_and_serve(sdb_fe_socket_t *sock, sdb_fe_loop_t *loop)
 {
-	sdb_channel_t *chan;
 	fd_set sockets;
 	int max_listen_fd = 0;
 	size_t i;
@@ -427,18 +553,15 @@ sdb_fe_sock_listen_and_serve(sdb_fe_socket_t *sock, sdb_fe_loop_t *loop)
 	/* XXX: make the number of threads configurable */
 	pthread_t handler_threads[5];
 
-	if ((! sock) || (! sock->listeners_num) || (! loop))
+	if ((! sock) || (! sock->listeners_num) || (! loop) || sock->chan)
 		return -1;
 
 	FD_ZERO(&sockets);
-
 	for (i = 0; i < sock->listeners_num; ++i) {
 		listener_t *listener = sock->listeners + i;
 
-		if (listen(listener->sock_fd, /* backlog = */ 32)) {
-			char buf[1024];
-			sdb_log(SDB_LOG_ERR, "frontend: Failed to listen on socket %s: %s",
-					listener->address, sdb_strerror(errno, buf, sizeof(buf)));
+		if (listener_listen(listener)) {
+			socket_close(sock);
 			return -1;
 		}
 
@@ -447,37 +570,37 @@ sdb_fe_sock_listen_and_serve(sdb_fe_socket_t *sock, sdb_fe_loop_t *loop)
 			max_listen_fd = listener->sock_fd;
 	}
 
-	chan = sdb_channel_create(1024, sizeof(connection_obj_t *));
-	if (! chan)
+	sock->chan = sdb_channel_create(1024, sizeof(connection_obj_t *));
+	if (! sock->chan) {
+		socket_close(sock);
 		return -1;
+	}
 
 	memset(&handler_threads, 0, sizeof(handler_threads));
 	/* XXX: error handling */
 	for (i = 0; i < SDB_STATIC_ARRAY_LEN(handler_threads); ++i)
 		pthread_create(&handler_threads[i], /* attr = */ NULL,
-				connection_handler, /* arg = */ chan);
+				connection_handler, /* arg = */ sock);
 
 	while (loop->do_loop) {
+		struct timeval timeout = { 1, 0 }; /* one second */
+		sdb_llist_iter_t *iter;
+
+		int max_fd = max_listen_fd;
 		fd_set ready;
 		fd_set exceptions;
-		int max_fd;
 		int n;
 
-		struct timeval timeout = { 1, 0 }; /* one second */
-		sdb_llist_iter_t *iter;
-
 		FD_ZERO(&ready);
 		FD_ZERO(&exceptions);
 
 		ready = sockets;
 
-		max_fd = max_listen_fd;
-
 		iter = sdb_llist_get_iter(sock->open_connections);
 		if (! iter) {
 			sdb_log(SDB_LOG_ERR, "frontend: Failed to acquire iterator "
 					"for open connections");
-			return -1;
+			break;
 		}
 
 		while (sdb_llist_iter_has_next(iter)) {
@@ -500,48 +623,27 @@ sdb_fe_sock_listen_and_serve(sdb_fe_socket_t *sock, sdb_fe_loop_t *loop)
 
 			sdb_log(SDB_LOG_ERR, "frontend: Failed to monitor sockets: %s",
 					sdb_strerror(errno, buf, sizeof(buf)));
-			return -1;
+			break;
 		}
-
-		if (! n)
+		else if (! n)
 			continue;
 
-		for (i = 0; i < sock->listeners_num; ++i) {
-			listener_t *listener = sock->listeners + i;
-			if (FD_ISSET(listener->sock_fd, &ready))
-				if (accept_connection(sock, listener))
-					continue;
-		}
-
-		iter = sdb_llist_get_iter(sock->open_connections);
-		if (! iter) {
-			sdb_log(SDB_LOG_ERR, "frontend: Failed to acquire iterator "
-					"for open connections");
-			return -1;
-		}
-
-		while (sdb_llist_iter_has_next(iter)) {
-			sdb_object_t *obj = sdb_llist_iter_get_next(iter);
-
-			if (FD_ISSET(CONN(obj)->conn.fd, &exceptions))
-				sdb_log(SDB_LOG_INFO, "Exception on fd %d",
-						CONN(obj)->conn.fd);
-
-			if (FD_ISSET(CONN(obj)->conn.fd, &ready)) {
-				sdb_log(SDB_LOG_INFO, "Data on fd %d", CONN(obj)->conn.fd);
-				sdb_llist_iter_remove_current(iter);
-				sdb_channel_write(chan, &obj);
-			}
-		}
-		sdb_llist_iter_destroy(iter);
+		/* handle new and open connections */
+		if (socket_handle_incoming(sock, &ready, &exceptions))
+			break;
 	}
 
+	socket_close(sock);
+
 	sdb_log(SDB_LOG_INFO, "frontend: Waiting for connection handler threads "
 			"to terminate");
-	if (! sdb_channel_shutdown(chan))
+	if (! sdb_channel_shutdown(sock->chan))
 		for (i = 0; i < SDB_STATIC_ARRAY_LEN(handler_threads); ++i)
 			pthread_join(handler_threads[i], NULL);
 	/* else: we tried our best; let the operating system clean up */
+
+	sdb_channel_destroy(sock->chan);
+	sock->chan = NULL;
 	return 0;
 } /* sdb_fe_sock_listen_and_server */