X-Git-Url: https://git.tokkee.org/?p=sysdb.git;a=blobdiff_plain;f=src%2Ffrontend%2Fsock.c;h=3b9799496df8bf1e70d501393e36b91de0ebd86e;hp=a389a142b94f8a1a609a02a2ae1773239dc0e624;hb=39a45905e0b237e458b1826ff9b4fad1c4a59550;hpb=635debdd1d9f4b4982cdff91fcb244b64ea341fc

diff --git a/src/frontend/sock.c b/src/frontend/sock.c
index a389a14..3b97994 100644
--- a/src/frontend/sock.c
+++ b/src/frontend/sock.c
@@ -25,16 +25,21 @@
  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
+#if HAVE_CONFIG_H
+#	include "config.h"
+#endif /* HAVE_CONFIG_H */
+
 #include "sysdb.h"
-#include "core/error.h"
 #include "core/object.h"
+#include "frontend/connection-private.h"
 #include "frontend/sock.h"
 
 #include "utils/channel.h"
+#include "utils/error.h"
 #include "utils/llist.h"
+#include "utils/strbuf.h"
 
 #include <assert.h>
-
 #include <errno.h>
 
 #include <stdio.h>
@@ -43,8 +48,6 @@
 
 #include <unistd.h>
 
-#include <fcntl.h>
-
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/select.h>
@@ -53,26 +56,10 @@
 
 #include <pthread.h>
 
-/* name of connection objects */
-#define CONN_FD_PREFIX "conn#"
-#define CONN_FD_PLACEHOLDER "XXXXXXX"
-
 /*
  * private data types
  */
 
-typedef struct {
-	int fd;
-	struct sockaddr_storage client_addr;
-	socklen_t client_addr_len;
-} connection_t;
-
-typedef struct {
-	sdb_object_t super;
-	connection_t conn;
-} connection_obj_t;
-#define CONN(obj) ((connection_obj_t *)(obj))
-
 typedef struct {
 	char *address;
 	int   type;
@@ -85,6 +72,7 @@ typedef struct {
 	const char *prefix;
 
 	int (*opener)(listener_t *);
+	void (*closer)(listener_t *);
 } fe_listener_impl_t;
 
 struct sdb_fe_socket {
@@ -92,6 +80,10 @@ 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;
 };
 
 /*
@@ -117,6 +109,13 @@ open_unix_sock(listener_t *listener)
 	strncpy(sa.sun_path, listener->address + strlen("unix:"),
 			sizeof(sa.sun_path));
 
+	if (unlink(listener->address + strlen("unix:")) && (errno != ENOENT)) {
+		char errbuf[1024];
+		sdb_log(SDB_LOG_WARNING, "frontend: Failed to remove stale UNIX "
+				"socket %s: %s", listener->address + strlen("unix:"),
+				sdb_strerror(errno, errbuf, sizeof(errbuf)));
+	}
+
 	status = bind(listener->sock_fd, (struct sockaddr *)&sa, sizeof(sa));
 	if (status) {
 		char buf[1024];
@@ -127,6 +126,20 @@ open_unix_sock(listener_t *listener)
 	return 0;
 } /* open_unix_sock */
 
+static void
+close_unix_sock(listener_t *listener)
+{
+	assert(listener);
+	if (! listener->address)
+		return;
+
+	if (listener->sock_fd >= 0)
+		close(listener->sock_fd);
+	listener->sock_fd = -1;
+
+	unlink(listener->address + strlen("unix:"));
+} /* close_unix_sock */
+
 /*
  * private variables
  */
@@ -137,13 +150,46 @@ enum {
 	LISTENER_UNIXSOCK = 0,
 };
 static fe_listener_impl_t listener_impls[] = {
-	{ LISTENER_UNIXSOCK, "unix", open_unix_sock },
+	{ LISTENER_UNIXSOCK, "unix", open_unix_sock, close_unix_sock },
 };
 
 /*
  * private helper functions
  */
 
+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_impls[listener->type].closer)
+		listener_impls[listener->type].closer(listener);
+
+	if (listener->sock_fd >= 0)
+		close(listener->sock_fd);
+	listener->sock_fd = -1;
+} /* listener_close */
+
 static int
 get_type(const char *address)
 {
@@ -175,11 +221,11 @@ listener_destroy(listener_t *listener)
 	if (! listener)
 		return;
 
-	if (listener->sock_fd >= 0)
-		close(listener->sock_fd);
+	listener_close(listener);
 
 	if (listener->address)
 		free(listener->address);
+	listener->address = NULL;
 } /* listener_destroy */
 
 static listener_t *
@@ -196,7 +242,7 @@ listener_create(sdb_fe_socket_t *sock, const char *address)
 	}
 
 	listener = realloc(sock->listeners,
-			sock->listeners_num * sizeof(*sock->listeners));
+			(sock->listeners_num + 1) * sizeof(*sock->listeners));
 	if (! listener) {
 		char buf[1024];
 		sdb_log(SDB_LOG_ERR, "frontend: Failed to allocate memory: %s",
@@ -228,75 +274,15 @@ listener_create(sdb_fe_socket_t *sock, const char *address)
 	return listener;
 } /* listener_create */
 
-/*
- * private data types
- */
-
-static int
-connection_init(sdb_object_t *obj, va_list ap)
-{
-	connection_t *conn;
-	int sock_fd;
-	int sock_fl;
-
-	assert(obj);
-	conn = &CONN(obj)->conn;
-
-	sock_fd = va_arg(ap, int);
-
-	conn->client_addr_len = sizeof(conn->client_addr);
-	conn->fd = accept(sock_fd, (struct sockaddr *)&conn->client_addr,
-			&conn->client_addr_len);
-
-	if (conn->fd < 0) {
-		char buf[1024];
-		sdb_log(SDB_LOG_ERR, "frontend: Failed to accept remote "
-				"connection: %s", sdb_strerror(errno,
-					buf, sizeof(buf)));
-		return -1;
-	}
-
-	if (conn->client_addr.ss_family != AF_UNIX) {
-		sdb_log(SDB_LOG_ERR, "frontend: Accepted connection using "
-				"unexpected family type %d", conn->client_addr.ss_family);
-		return -1;
-	}
-
-	sock_fl = fcntl(conn->fd, F_GETFL);
-	if (fcntl(conn->fd, F_SETFL, sock_fl | O_NONBLOCK)) {
-		char buf[1024];
-		sdb_log(SDB_LOG_ERR, "frontend: Failed to switch connection conn#%i "
-				"to non-blocking mode: %s", conn->fd,
-				sdb_strerror(errno, buf, sizeof(buf)));
-		return -1;
-	}
-
-	sdb_log(SDB_LOG_DEBUG, "frontend: Accepted connection on fd=%i",
-			conn->fd);
-
-	/* update the object name */
-	snprintf(obj->name + strlen(CONN_FD_PREFIX),
-			strlen(CONN_FD_PLACEHOLDER), "%i", conn->fd);
-	return 0;
-} /* connection_init */
-
 static void
-connection_destroy(sdb_object_t *obj)
+socket_close(sdb_fe_socket_t *sock)
 {
-	connection_t *conn;
-
-	assert(obj);
-	conn = &CONN(obj)->conn;
-
-	close(conn->fd);
-	conn->fd = -1;
-} /* connection_destroy */
+	size_t i;
 
-static sdb_type_t connection_type = {
-	/* size = */ sizeof(connection_obj_t),
-	/* init = */ connection_init,
-	/* destroy = */ connection_destroy,
-};
+	assert(sock);
+	for (i = 0; i < sock->listeners_num; ++i)
+		listener_close(sock->listeners + i);
+} /* socket_close */
 
 /*
  * connection handler functions
@@ -305,17 +291,18 @@ static sdb_type_t connection_type = {
 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 */
-		connection_obj_t *conn;
+		sdb_conn_t *conn;
 		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];
 
@@ -329,37 +316,83 @@ connection_handler(void *data)
 			continue;
 		}
 
-		/* XXX */
-		sdb_log(SDB_LOG_INFO, "frontend: Data available on connection fd=%i\n",
-				conn->conn.fd);
+		status = (int)sdb_connection_read(conn);
+		if (status <= 0) {
+			/* error or EOF -> close connection */
+			sdb_object_deref(SDB_OBJ(conn));
+			continue;
+		}
+
+		/* return the connection to the main loop */
+		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;
+	int status;
 
-	/* the X's 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);
+	obj = SDB_OBJ(sdb_connection_accept(listener->sock_fd));
 	if (! obj)
 		return -1;
 
-	if (sdb_llist_append(sock->open_connections, obj)) {
+	status = sdb_llist_append(sock->open_connections, obj);
+	if (status)
 		sdb_log(SDB_LOG_ERR, "frontend: Failed to append "
 				"connection %s to list of open connections",
 				obj->name);
-		sdb_object_deref(obj);
+
+	/* hand ownership over to the list; or destroy in case of an error */
+	sdb_object_deref(obj);
+	return status;
+} /* 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;
 	}
 
-	/* hand ownership over to the list */
-	sdb_object_deref(obj);
+	while (sdb_llist_iter_has_next(iter)) {
+		sdb_object_t *obj = sdb_llist_iter_get_next(iter);
+
+		if (FD_ISSET(CONN(obj)->fd, exceptions))
+			sdb_log(SDB_LOG_INFO, "Exception on fd %d",
+					CONN(obj)->fd);
+
+		if (FD_ISSET(CONN(obj)->fd, ready)) {
+			sdb_llist_iter_remove_current(iter);
+			sdb_channel_write(sock->chan, &obj);
+		}
+	}
+	sdb_llist_iter_destroy(iter);
 	return 0;
-} /* accept_connection */
+} /* socket_handle_incoming */
 
 /*
  * public API
@@ -419,26 +452,26 @@ 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;
 
-	/* XXX: make the number of threads configurable */
-	pthread_t handler_threads[5];
+	pthread_t handler_threads[loop->num_threads];
+	size_t num_threads;
 
-	if ((! sock) || (! sock->listeners_num) || (! loop))
+	if ((! sock) || (! sock->listeners_num) || sock->chan
+			|| (! loop) || (loop->num_threads <= 0))
 		return -1;
 
-	FD_ZERO(&sockets);
+	if (! loop->do_loop)
+		return 0;
 
+	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;
 		}
 
@@ -447,46 +480,60 @@ 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(sdb_conn_t *));
+	if (! sock->chan) {
+		socket_close(sock);
 		return -1;
+	}
 
+	sdb_log(SDB_LOG_INFO, "frontend: Starting %d connection "
+			"handler thread%s managing %d listener%s",
+			loop->num_threads, loop->num_threads == 1 ? "" : "s",
+			sock->listeners_num, sock->listeners_num == 1 ? "" : "s");
+
+	num_threads = loop->num_threads;
 	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);
+	for (i = 0; i < num_threads; ++i) {
+		errno = 0;
+		if (pthread_create(&handler_threads[i], /* attr = */ NULL,
+					connection_handler, /* arg = */ sock)) {
+			char errbuf[1024];
+			sdb_log(SDB_LOG_ERR, "frontend: Failed to create "
+					"connection handler thread: %s",
+					sdb_strerror(errno, errbuf, sizeof(errbuf)));
+			num_threads = i;
+			break;
+		}
+	}
 
-	while (loop->do_loop) {
+	while (loop->do_loop && num_threads) {
+		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)) {
 			sdb_object_t *obj = sdb_llist_iter_get_next(iter);
-			FD_SET(CONN(obj)->conn.fd, &ready);
-			FD_SET(CONN(obj)->conn.fd, &exceptions);
+			FD_SET(CONN(obj)->fd, &ready);
+			FD_SET(CONN(obj)->fd, &exceptions);
 
-			if (CONN(obj)->conn.fd > max_fd)
-				max_fd = CONN(obj)->conn.fd;
+			if (CONN(obj)->fd > max_fd)
+				max_fd = CONN(obj)->fd;
 		}
 		sdb_llist_iter_destroy(iter);
 
@@ -500,48 +547,30 @@ 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))
-		for (i = 0; i < SDB_STATIC_ARRAY_LEN(handler_threads); ++i)
+	if (! sdb_channel_shutdown(sock->chan))
+		for (i = 0; i < num_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;
+
+	if (! num_threads)
+		return -1;
 	return 0;
 } /* sdb_fe_sock_listen_and_server */