From: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Date: Tue, 4 Oct 2011 00:25:10 +0000 (+1100)
Subject: Autoreconnect: autoreconnect was completely broken. Reimplement it so that it reconne... 
X-Git-Tag: upstream/1.9.6^2~293
X-Git-Url: https://git.piment-noir.org/?a=commitdiff_plain;h=1744ef90110e99efc5b3c10953ff664b7276517c;p=deb_libnfs.git

Autoreconnect: autoreconnect was completely broken. Reimplement it so that it reconnects properly on session failure.
---

diff --git a/include/libnfs-private.h b/include/libnfs-private.h
index 4c8594c..85cc8f9 100644
--- a/include/libnfs-private.h
+++ b/include/libnfs-private.h
@@ -45,6 +45,10 @@ struct rpc_context {
        int is_udp;
        struct sockaddr *udp_dest;
        int is_broadcast;
+
+       /* track the address we connect to so we can auto-reconnect on session failure */
+       struct sockaddr_storage s;
+       int auto_reconnect;
 };
 
 struct rpc_pdu {
@@ -85,3 +89,6 @@ int rpc_set_udp_destination(struct rpc_context *rpc, char *addr, int port, int i
 struct rpc_context *rpc_init_udp_context(void);
 struct sockaddr *rpc_get_recv_sockaddr(struct rpc_context *rpc);
 
+void rpc_set_autoreconnect(struct rpc_context *rpc);
+void rpc_unset_autoreconnect(struct rpc_context *rpc);
+
diff --git a/lib/libnfs-sync.c b/lib/libnfs-sync.c
index 97d5a61..0340eda 100644
--- a/lib/libnfs-sync.c
+++ b/lib/libnfs-sync.c
@@ -105,19 +105,6 @@ static void wait_for_nfs_reply(struct nfs_context *nfs, struct sync_cb_data *cb_
 			cb_data->status = -EIO;
 			break;
 		}
-		if (nfs_get_fd(nfs) == -1) {
-			char *server = strdup(nfs_get_server(nfs));
-			char *export = strdup(nfs_get_export(nfs));
-
-			if (nfs_mount(nfs, server, export) != 0) {
-				nfs_set_error(nfs, "Failed to reconnect to nfs server %s", nfs_get_error(nfs));
-				free(server);
-				free(export);
-				break;
-			}
-			free(server);
-			free(export);
-		}
 	}
 }
 
diff --git a/lib/libnfs.c b/lib/libnfs.c
index c1b4962..2f7ce09 100644
--- a/lib/libnfs.c
+++ b/lib/libnfs.c
@@ -352,6 +352,8 @@ static void nfs_mount_6_cb(struct rpc_context *rpc, int status, void *command_da
 		free_nfs_cb_data(data);
 		return;
 	}
+	/* NFS TCP connections we want to autoreconnect after sessions are torn down (due to inactivity or error) */
+	rpc_set_autoreconnect(rpc);
 }
 
 
@@ -499,12 +501,10 @@ int nfs_mount_async(struct nfs_context *nfs, const char *server, const char *exp
 	new_export = strdup(export);
 	if (nfs->server != NULL) {
 		free(nfs->server);
-		nfs->server = NULL;
 	}
 	nfs->server        = new_server;
 	if (nfs->export != NULL) {
 		free(nfs->export);
-		nfs->export = NULL;
 	}
 	nfs->export        = new_export;
 	data->nfs          = nfs;
diff --git a/lib/socket.c b/lib/socket.c
index bc101e7..00c65dd 100644
--- a/lib/socket.c
+++ b/lib/socket.c
@@ -53,7 +53,8 @@
 #endif
 
 
-static int rpc_disconnect_requeue(struct rpc_context *rpc);
+static int rpc_reconnect_requeue(struct rpc_context *rpc);
+static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s);
 
 static void set_nonblocking(int fd)
 {
@@ -310,7 +311,7 @@ int rpc_service(struct rpc_context *rpc, int revents)
 
 	if (revents & POLLIN) {
 		if (rpc_read_from_socket(rpc) != 0) {
-		  	rpc_disconnect_requeue(rpc);
+		  	rpc_reconnect_requeue(rpc);
 			return 0;
 		}
 	}
@@ -325,37 +326,28 @@ int rpc_service(struct rpc_context *rpc, int revents)
 	return 0;
 }
 
-int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
+void rpc_set_autoreconnect(struct rpc_context *rpc)
 {
-	struct sockaddr_storage s;
-	struct sockaddr_in *sin = (struct sockaddr_in *)&s;
-	int socksize;
-
-	if (rpc->fd != -1) {
-		rpc_set_error(rpc, "Trying to connect while already connected");
-		return -1;
-	}
+	rpc->auto_reconnect = 1;
+}
 
-	if (rpc->is_udp != 0) {
-		rpc_set_error(rpc, "Trying to connect on UDP socket");
-		return -1;
-	}
+void rpc_unset_autoreconnect(struct rpc_context *rpc)
+{
+	rpc->auto_reconnect = 0;
+}
 
-	sin->sin_family = AF_INET;
-	sin->sin_port   = htons(port);
-	if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
-		rpc_set_error(rpc, "Not a valid server ip address");
-		return -1;
-	}
+static int rpc_connect_sockaddr_async(struct rpc_context *rpc, struct sockaddr_storage *s)
+{
+	int socksize;
 
-	switch (s.ss_family) {
+	switch (s->ss_family) {
 	case AF_INET:
 		socksize = sizeof(struct sockaddr_in);
-#ifdef HAVE_SOCKADDR_LEN
-		sin->sin_len = socksize;
-#endif
 		rpc->fd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 		break;
+	default:
+		rpc_set_error(rpc, "Can not handle AF_FAMILY:%d", s->ss_family);
+		return -1;
 	}
 
 	if (rpc->fd == -1) {
@@ -363,9 +355,6 @@ int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc
 		return -1;
 	}
 
-	rpc->connect_cb  = cb;
-	rpc->connect_data = private_data;
-
 
 #if !defined(WIN32)
 	/* Some systems allow you to set capabilities on an executable
@@ -409,9 +398,9 @@ int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc
 	set_nonblocking(rpc->fd);
 
 #if defined(WIN32)
-	if (connect(rpc->fd, (struct sockaddr *)&s, socksize) == 0 && errno != EINPROGRESS   )
+	if (connect(rpc->fd, (struct sockaddr *)s, socksize) == 0 && errno != EINPROGRESS   )
 #else
-	if (connect(rpc->fd, (struct sockaddr *)&s, socksize) != 0 && errno != EINPROGRESS) 
+	if (connect(rpc->fd, (struct sockaddr *)s, socksize) != 0 && errno != EINPROGRESS) 
 #endif
 	{
 		rpc_set_error(rpc, "connect() to server failed");
@@ -421,8 +410,52 @@ int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc
 	return 0;
 }	    
 
+int rpc_connect_async(struct rpc_context *rpc, const char *server, int port, rpc_cb cb, void *private_data)
+{
+	struct sockaddr_in *sin = (struct sockaddr_in *)&rpc->s;
+
+	if (rpc->fd != -1) {
+		rpc_set_error(rpc, "Trying to connect while already connected");
+		return -1;
+	}
+
+	if (rpc->is_udp != 0) {
+		rpc_set_error(rpc, "Trying to connect on UDP socket");
+		return -1;
+	}
+
+	rpc->auto_reconnect = 0;
+
+	sin->sin_family = AF_INET;
+	sin->sin_port   = htons(port);
+	if (inet_pton(AF_INET, server, &sin->sin_addr) != 1) {
+		rpc_set_error(rpc, "Not a valid server ip address");
+		return -1;
+	}
+
+
+	switch (rpc->s.ss_family) {
+	case AF_INET:
+#ifdef HAVE_SOCKADDR_LEN
+		sin->sin_len = sizeof(struct sockaddr_in);
+#endif
+		break;
+	}
+
+	rpc->connect_cb  = cb;
+	rpc->connect_data = private_data;
+
+	if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
+		return -1;
+	}
+
+	return 0;
+}	    
+
 int rpc_disconnect(struct rpc_context *rpc, char *error)
 {
+	rpc_unset_autoreconnect(rpc);
+
 	if (rpc->fd != -1) {
 #if defined(WIN32)
 		closesocket(rpc->fd);
@@ -439,8 +472,18 @@ int rpc_disconnect(struct rpc_context *rpc, char *error)
 	return 0;
 }
 
-/* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue */
-static int rpc_disconnect_requeue(struct rpc_context *rpc)
+static void reconnect_cb(struct rpc_context *rpc, int status, void *data _U_, void *private_data)
+{
+	if (status != RPC_STATUS_SUCCESS) {
+		rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
+		return;
+	}
+
+	rpc->is_connected = 1;
+}
+
+/* disconnect but do not error all PDUs, just move pdus in-flight back to the outqueue and reconnect */
+static int rpc_reconnect_requeue(struct rpc_context *rpc)
 {
 	struct rpc_pdu *pdu;
 
@@ -461,6 +504,17 @@ static int rpc_disconnect_requeue(struct rpc_context *rpc)
 	for (pdu=rpc->waitpdu; pdu; pdu=pdu->next) {
 		SLIST_REMOVE(&rpc->waitpdu, pdu);
 		SLIST_ADD(&rpc->outqueue, pdu);
+		/* we have to re-send the whole pdu again */
+		pdu->written = 0;
+	}
+
+	if (rpc->auto_reconnect != 0) {
+		rpc->connect_cb  = reconnect_cb;
+
+		if (rpc_connect_sockaddr_async(rpc, &rpc->s) != 0) {
+			rpc_error_all_pdus(rpc, "RPC ERROR: Failed to reconnect async");
+			return -1;
+		}
 	}
 
 	return 0;