X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=src%2Ffrontend%2Fsock.c;h=53a8a860d6f5a811181f0e4ba831d9e58704165f;hb=c58c4edb82a8f5ee35b7fa3e47610ed86ed544ce;hp=e2c52ce31b2cbf3a0dba089187de4efd8ceac5fb;hpb=4a0488a16be1c6aa0e8552b35a91094c36e84f20;p=sysdb.git

diff --git a/src/frontend/sock.c b/src/frontend/sock.c
index e2c52ce..53a8a86 100644
--- a/src/frontend/sock.c
+++ b/src/frontend/sock.c
@@ -27,19 +27,24 @@
 
 #include "sysdb.h"
 #include "core/error.h"
+#include "core/object.h"
 #include "frontend/sock.h"
 
 #include "utils/channel.h"
+#include "utils/llist.h"
 
 #include <assert.h>
 
 #include <errno.h>
 
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include <unistd.h>
 
+#include <fcntl.h>
+
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/select.h>
@@ -48,15 +53,22 @@
 
 #include <pthread.h>
 
+/* name of connection objects */
+#define CONN_FD_PREFIX "conn#"
+#define CONN_FD_PLACEHOLDER "XXXXXXX"
+
 /*
  * private data types
  */
 
 typedef struct {
+	sdb_object_t super;
+
 	int fd;
 	struct sockaddr_storage client_addr;
 	socklen_t client_addr_len;
-} connection_t;
+} connection_obj_t;
+#define CONN(obj) ((connection_obj_t *)(obj))
 
 typedef struct {
 	char *address;
@@ -75,6 +87,12 @@ typedef struct {
 struct sdb_fe_socket {
 	listener_t *listeners;
 	size_t listeners_num;
+
+	sdb_llist_t *open_connections;
+
+	/* channel used for communication between main
+	 * and connection handler threads */
+	sdb_channel_t *chan;
 };
 
 /*
@@ -90,7 +108,7 @@ open_unix_sock(listener_t *listener)
 	listener->sock_fd = socket(AF_UNIX, SOCK_STREAM, 0);
 	if (listener->sock_fd < 0) {
 		char buf[1024];
-		sdb_log(SDB_LOG_ERR, "sock: Failed to open UNIX socket %s: %s",
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to open UNIX socket %s: %s",
 				listener->address, sdb_strerror(errno, buf, sizeof(buf)));
 		return -1;
 	}
@@ -103,7 +121,7 @@ open_unix_sock(listener_t *listener)
 	status = bind(listener->sock_fd, (struct sockaddr *)&sa, sizeof(sa));
 	if (status) {
 		char buf[1024];
-		sdb_log(SDB_LOG_ERR, "sock: Failed to bind to UNIX socket %s: %s",
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to bind to UNIX socket %s: %s",
 				listener->address, sdb_strerror(errno, buf, sizeof(buf)));
 		return -1;
 	}
@@ -160,6 +178,7 @@ listener_destroy(listener_t *listener)
 
 	if (listener->sock_fd >= 0)
 		close(listener->sock_fd);
+	listener->sock_fd = -1;
 
 	if (listener->address)
 		free(listener->address);
@@ -173,7 +192,7 @@ listener_create(sdb_fe_socket_t *sock, const char *address)
 
 	type = get_type(address);
 	if (type < 0) {
-		sdb_log(SDB_LOG_ERR, "sock: Unsupported address type specified "
+		sdb_log(SDB_LOG_ERR, "frontend: Unsupported address type specified "
 				"in listen address '%s'", address);
 		return NULL;
 	}
@@ -182,7 +201,7 @@ listener_create(sdb_fe_socket_t *sock, const char *address)
 			sock->listeners_num * sizeof(*sock->listeners));
 	if (! listener) {
 		char buf[1024];
-		sdb_log(SDB_LOG_ERR, "sock: Failed to allocate memory: %s",
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to allocate memory: %s",
 				sdb_strerror(errno, buf, sizeof(buf)));
 		return NULL;
 	}
@@ -194,7 +213,7 @@ listener_create(sdb_fe_socket_t *sock, const char *address)
 	listener->address = strdup(address);
 	if (! listener->address) {
 		char buf[1024];
-		sdb_log(SDB_LOG_ERR, "sock: Failed to allocate memory: %s",
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to allocate memory: %s",
 				sdb_strerror(errno, buf, sizeof(buf)));
 		listener_destroy(listener);
 		return NULL;
@@ -211,24 +230,167 @@ 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
+ */
+
+static int
+connection_init(sdb_object_t *obj, va_list ap)
+{
+	connection_obj_t *conn;
+	int sock_fd;
+	int sock_fl;
+
+	assert(obj);
+	conn = CONN(obj);
+
+	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)
+{
+	connection_obj_t *conn;
+
+	assert(obj);
+	conn = CONN(obj);
+
+	sdb_log(SDB_LOG_DEBUG, "frontend: Closing connection on fd=%i", conn->fd);
+	close(conn->fd);
+	conn->fd = -1;
+} /* connection_destroy */
+
+static sdb_type_t connection_type = {
+	/* size = */ sizeof(connection_obj_t),
+	/* init = */ connection_init,
+	/* destroy = */ connection_destroy,
+};
+
 /*
  * 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 */
-		connection_t conn;
+		connection_obj_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];
 
@@ -237,27 +399,92 @@ connection_handler(void *data)
 			if (errno == EBADF) /* channel shut down */
 				break;
 
-			sdb_log(SDB_LOG_ERR, "sock: Failed to read from channel: %s",
+			sdb_log(SDB_LOG_ERR, "frontend: Failed to read from channel: %s",
 					sdb_strerror(errno, buf, sizeof(buf)));
 			continue;
 		}
 
-		if (conn.fd < 0)
-			continue;
-
-		if (conn.client_addr.ss_family != AF_UNIX) {
-			sdb_log(SDB_LOG_ERR, "sock: Accepted connection using unexpected "
-					"family type %d", conn.client_addr.ss_family);
-			continue;
+		status = connection_read(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);
+			}
 
-		/* XXX */
-		sdb_log(SDB_LOG_INFO, "Accepted connection on fd=%i\n", conn.fd);
-		close(conn.fd);
+			/* pass ownership back to list; or destroy in case of an error */
+			sdb_object_deref(SDB_OBJ(conn));
+		}
 	}
 	return NULL;
 } /* connection_handler */
 
+static int
+connection_accept(sdb_fe_socket_t *sock, listener_t *listener)
+{
+	sdb_object_t *obj;
+
+	/* 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)
+		return -1;
+
+	if (sdb_llist_append(sock->open_connections, obj)) {
+		sdb_log(SDB_LOG_ERR, "frontend: Failed to append "
+				"connection %s to list of open connections",
+				obj->name);
+		sdb_object_deref(obj);
+		return -1;
+	}
+
+	/* hand ownership over to the list */
+	sdb_object_deref(obj);
+	return 0;
+} /* 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)->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;
+} /* socket_handle_incoming */
+
 /*
  * public API
  */
@@ -270,6 +497,12 @@ sdb_fe_sock_create(void)
 	sock = calloc(1, sizeof(*sock));
 	if (! sock)
 		return NULL;
+
+	sock->open_connections = sdb_llist_create();
+	if (! sock->open_connections) {
+		sdb_fe_sock_destroy(sock);
+		return NULL;
+	}
 	return sock;
 } /* sdb_fe_sock_create */
 
@@ -286,6 +519,10 @@ sdb_fe_sock_destroy(sdb_fe_socket_t *sock)
 	}
 	if (sock->listeners)
 		free(sock->listeners);
+	sock->listeners = NULL;
+
+	sdb_llist_destroy(sock->open_connections);
+	sock->open_connections = NULL;
 	free(sock);
 } /* sdb_fe_sock_destroy */
 
@@ -306,98 +543,104 @@ 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_fd = 0;
+	int max_listen_fd = 0;
 	size_t i;
 
 	/* 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, "sock: Failed to listen on socket %s: %s",
-					listener->address, sdb_strerror(errno, buf, sizeof(buf)));
+		if (listener_listen(listener)) {
+			socket_close(sock);
 			return -1;
 		}
 
 		FD_SET(listener->sock_fd, &sockets);
-		if (listener->sock_fd > max_fd)
-			max_fd = listener->sock_fd;
+		if (listener->sock_fd > max_listen_fd)
+			max_listen_fd = listener->sock_fd;
 	}
 
-	chan = sdb_channel_create(1024, sizeof(connection_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) {
-		fd_set ready = sockets;
+		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 n;
 
-		struct timeval timeout = { 1, 0 }; /* one second */
+		FD_ZERO(&ready);
+		FD_ZERO(&exceptions);
+
+		ready = sockets;
+
+		iter = sdb_llist_get_iter(sock->open_connections);
+		if (! iter) {
+			sdb_log(SDB_LOG_ERR, "frontend: Failed to acquire iterator "
+					"for open connections");
+			break;
+		}
+
+		while (sdb_llist_iter_has_next(iter)) {
+			sdb_object_t *obj = sdb_llist_iter_get_next(iter);
+			FD_SET(CONN(obj)->fd, &ready);
+			FD_SET(CONN(obj)->fd, &exceptions);
+
+			if (CONN(obj)->fd > max_fd)
+				max_fd = CONN(obj)->fd;
+		}
+		sdb_llist_iter_destroy(iter);
 
 		errno = 0;
-		n = select(max_fd + 1, &ready, NULL, NULL, &timeout);
+		n = select(max_fd + 1, &ready, NULL, &exceptions, &timeout);
 		if (n < 0) {
 			char buf[1024];
 
 			if (errno == EINTR)
 				continue;
 
-			sdb_log(SDB_LOG_ERR, "sock: Failed to monitor sockets: %s",
+			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)) {
-				connection_t conn;
-
-				memset(&conn, 0, sizeof(conn));
-				conn.client_addr_len = sizeof(conn.client_addr);
-
-				conn.fd = accept(listener->sock_fd,
-						(struct sockaddr *)&conn.client_addr,
-						&conn.client_addr_len);
-
-				if (conn.fd < 0) {
-					char buf[1024];
-					sdb_log(SDB_LOG_ERR, "sock: Failed to accept remote "
-							"connection: %s", sdb_strerror(errno,
-								buf, sizeof(buf)));
-					continue;
-				}
-
-				sdb_channel_write(chan, &conn);
-			}
-		}
+		/* handle new and open connections */
+		if (socket_handle_incoming(sock, &ready, &exceptions))
+			break;
 	}
 
-	sdb_log(SDB_LOG_INFO, "sock: Waiting for connection handler threads "
+	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 */