Implement generic task queue to handle handshakes and maintenance

9 files changed, 171 insertions, 42 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 1e6bb83..c92e457 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -40,6 +40,7 @@ add_executable(fastd
   shell.c
   socket.c
   status.c
+  task.c
   vector.c
   verify.c
   ${BISON_fastd_config_parse_OUTPUTS}
diff --git a/src/fastd.c b/src/fastd.c
index 8723add..603def1 100644
--- a/src/fastd.c
+++ b/src/fastd.c
@@ -503,7 +503,7 @@ static inline void init(int argc, char *argv[]) {
 	init_config(&status_fd);
 
 	fastd_update_time();
-	ctx.next_maintenance = ctx.now + MAINTENANCE_INTERVAL;
+	fastd_task_schedule(&ctx.next_maintenance, TASK_TYPE_MAINTENANCE, ctx.now + MAINTENANCE_INTERVAL);
 
 	fastd_receive_unknown_init();
 
@@ -574,17 +574,6 @@ static inline void init(int argc, char *argv[]) {
 }
 
 
-/** Performs periodic maintenance tasks */
-static inline void maintenance(void) {
-	if (!fastd_timed_out(ctx.next_maintenance))
-		return;
-
-	fastd_socket_handle_binds();
-	fastd_peer_maintenance();
-
-	ctx.next_maintenance += MAINTENANCE_INTERVAL;
-}
-
 /** Reaps zombies of asynchronous shell commands. */
 static inline void reap_zombies(void) {
 	size_t i;
@@ -637,10 +626,9 @@ static inline void handle_signals(void) {
 
 /** A single iteration of fastd's main loop */
 static inline void run(void) {
-	fastd_peer_handle_handshake_queue();
+	fastd_task_handle();
 	fastd_poll_handle();
 
-	maintenance();
 	handle_signals();
 }
 
diff --git a/src/fastd.h b/src/fastd.h
index d15033c..9d44b21 100644
--- a/src/fastd.h
+++ b/src/fastd.h
@@ -41,6 +41,7 @@
 #include "poll.h"
 #include "sem.h"
 #include "shell.h"
+#include "task.h"
 #include "util.h"
 #include "vector.h"
 
@@ -312,8 +313,8 @@ struct fastd_context {
 	size_t peer_addr_ht_used;		/**< The current number of entries in the peer address hashtable */
 	VECTOR(fastd_peer_t *) *peer_addr_ht;	/**< An array of hash buckets for the peer hash table */
 
-	fastd_pqueue_t *handshake_queue;	/**< A priority queue of the peers currently queued for handshakes (ordered by the time of the next handshake) */
-	fastd_timeout_t next_maintenance;	/**< The time of the next maintenance call */
+	fastd_pqueue_t *task_queue;		/**< Priority queue of scheduled tasks */
+	fastd_task_t next_maintenance;		/**< Schedules the next maintenance call */
 
 	VECTOR(pid_t) async_pids;		/**< PIDs of asynchronously executed commands which still have to be reaped */
 	fastd_poll_fd_t async_rfd;		/**< The read side of the pipe used to send data from other threads to the main thread */
diff --git a/src/peer.c b/src/peer.c
index 87df22d..7f1ccb5 100644
--- a/src/peer.c
+++ b/src/peer.c
@@ -264,9 +264,7 @@ void fastd_peer_reset_socket(fastd_peer_t *peer) {
 */
 void fastd_peer_schedule_handshake(fastd_peer_t *peer, int delay) {
 	fastd_peer_unschedule_handshake(peer);
-
-	peer->handshake_entry.value = ctx.now + delay;
-	fastd_pqueue_insert(&ctx.handshake_queue, &peer->handshake_entry);
+	fastd_task_schedule(&peer->handshake_task, TASK_TYPE_HANDSHAKE, ctx.now + delay);
 }
 
 /** Checks if the peer group \e group1 lies in \e group2 */
@@ -819,13 +817,8 @@ static void send_handshake(fastd_peer_t *peer, fastd_remote_t *next_remote) {
 }
 
 /** Sends a handshake to one peer, if a scheduled handshake is due */
-void fastd_peer_handle_handshake_queue(void) {
-	if (!ctx.handshake_queue)
-		return;
-	if (!fastd_timed_out(ctx.handshake_queue->value))
-		return;
-
-	fastd_peer_t *peer = container_of(ctx.handshake_queue, fastd_peer_t, handshake_entry);
+void fastd_peer_handle_handshake_task(fastd_task_t *task) {
+	fastd_peer_t *peer = container_of(task, fastd_peer_t, handshake_task);
 
 	fastd_peer_schedule_handshake_default(peer);
 
diff --git a/src/peer.h b/src/peer.h
index 5f5da54..e83859e 100644
--- a/src/peer.h
+++ b/src/peer.h
@@ -91,7 +91,7 @@ struct fastd_peer {
 
 	fastd_peer_state_t state;			/**< The peer's state */
 
-	fastd_pqueue_t handshake_entry;			/**< Entry in the handshake queue */
+	fastd_task_t handshake_task;			/**< Entry in the handshake queue */
 	fastd_timeout_t last_handshake_timeout;		/**< No handshakes are sent to the peer until this timeout has occured to avoid flooding the peer */
 	fastd_timeout_t last_handshake_response_timeout; /**< All handshakes from last_handshake_address will be ignored until this timeout has occured */
 	fastd_timeout_t establish_handshake_timeout;	/**< A timeout during which all handshakes for this peer will be ignored after a new connection has been established */
@@ -175,7 +175,7 @@ static inline void fastd_peer_schedule_handshake_default(fastd_peer_t *peer) {
 
 /** Cancels a scheduled handshake */
 static inline void fastd_peer_unschedule_handshake(fastd_peer_t *peer) {
-	fastd_pqueue_remove(&peer->handshake_entry);
+	fastd_task_unschedule(&peer->handshake_task);
 }
 
 #ifdef WITH_DYNAMIC_PEERS
@@ -192,7 +192,7 @@ static inline void fastd_peer_set_verified(fastd_peer_t *peer, bool ok) {
 
 /** Checks if there's a handshake queued for the peer */
 static inline bool fastd_peer_handshake_scheduled(fastd_peer_t *peer) {
-	return fastd_pqueue_linked(&peer->handshake_entry);
+	return fastd_task_scheduled(&peer->handshake_task);
 }
 
 /** Checks if a peer is floating (is has at least one floating remote or no remotes at all) */
@@ -270,7 +270,7 @@ static inline bool fastd_eth_addr_is_unicast(fastd_eth_addr_t addr) {
 void fastd_peer_eth_addr_add(fastd_peer_t *peer, fastd_eth_addr_t addr);
 bool fastd_peer_find_by_eth_addr(const fastd_eth_addr_t addr, fastd_peer_t **peer);
 
-void fastd_peer_handle_handshake_queue(void);
+void fastd_peer_handle_handshake_task(fastd_task_t *task);
 void fastd_peer_maintenance(void);
 void fastd_peer_reset_all(void);
 
diff --git a/src/poll.c b/src/poll.c
index 0c4dfa9..fed7001 100644
--- a/src/poll.c
+++ b/src/poll.c
@@ -51,12 +51,13 @@
 #endif
 
 
-/** Returns the time to the next handshake or -1 */
-static inline int handshake_timeout(void) {
-	if (!ctx.handshake_queue)
+/** Returns the time to the next task or -1 */
+static inline int task_timeout(void) {
+	fastd_timeout_t timeout;
+	if (!fastd_task_timeout(&timeout))
 		return -1;
 
-	int diff_msec = ctx.handshake_queue->value - ctx.now;
+	int diff_msec = timeout - ctx.now;
 	if (diff_msec < 0)
 		return 0;
 	else
@@ -221,14 +222,7 @@ bool fastd_poll_fd_close(fastd_poll_fd_t *fd) {
 void fastd_poll_handle(void) {
 	size_t i;
 
-	int maintenance_timeout = ctx.next_maintenance - ctx.now;
-
-	if (maintenance_timeout < 0)
-		maintenance_timeout = 0;
-
-	int timeout = handshake_timeout();
-	if (timeout < 0 || timeout > maintenance_timeout)
-		timeout = maintenance_timeout;
+	int timeout = task_timeout();
 
 	if (!VECTOR_LEN(ctx.pollfds)) {
 		for (i = 0; i < VECTOR_LEN(ctx.fds); i++) {
diff --git a/src/task.c b/src/task.c
new file mode 100644
index 0000000..44a8ebf
--- /dev/null
+++ b/src/task.c
@@ -0,0 +1,78 @@
+/*
+  Copyright (c) 2012-2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/**
+   \file
+
+   Task queue
+*/
+
+#include "task.h"
+#include "peer.h"
+
+
+/** Performs periodic maintenance tasks */
+static inline void maintenance(void) {
+	fastd_socket_handle_binds();
+	fastd_peer_maintenance();
+
+	fastd_task_reschedule_relative(&ctx.next_maintenance, MAINTENANCE_INTERVAL);
+}
+
+static void handle_task(void) {
+	fastd_task_t *task = container_of(ctx.task_queue, fastd_task_t, entry);
+	fastd_pqueue_remove(ctx.task_queue);
+
+	switch (task->type) {
+	case TASK_TYPE_MAINTENANCE:
+		maintenance();
+		break;
+
+	case TASK_TYPE_HANDSHAKE:
+		fastd_peer_handle_handshake_task(task);
+		break;
+
+	default:
+		exit_bug("unknown task type");
+	}
+}
+
+void fastd_task_handle(void) {
+	while (ctx.task_queue && fastd_timed_out(ctx.task_queue->value))
+		handle_task();
+}
+
+void fastd_task_reschedule(fastd_task_t *task, fastd_timeout_t timeout) {
+	task->entry.value = timeout;
+	fastd_pqueue_insert(&ctx.task_queue, &task->entry);
+}
+
+bool fastd_task_timeout(fastd_timeout_t *timeout) {
+	if (!ctx.task_queue)
+		return false;
+
+	*timeout = ctx.task_queue->value;
+	return true;
+}
diff --git a/src/task.h b/src/task.h
new file mode 100644
index 0000000..4c00207
--- /dev/null
+++ b/src/task.h
@@ -0,0 +1,66 @@
+/*
+  Copyright (c) 2012-2015, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/**
+   \file
+
+   Task queue
+*/
+
+#pragma once
+
+#include "pqueue.h"
+
+
+struct fastd_task {
+	fastd_pqueue_t entry;
+	fastd_task_type_t type;
+};
+
+
+void fastd_task_handle(void);
+
+void fastd_task_reschedule(fastd_task_t *task, fastd_timeout_t timeout);
+
+
+static inline bool fastd_task_scheduled(fastd_task_t *task) {
+	return fastd_pqueue_linked(&task->entry);
+}
+
+static inline void fastd_task_unschedule(fastd_task_t *task) {
+	fastd_pqueue_remove(&task->entry);
+}
+
+static inline void fastd_task_reschedule_relative(fastd_task_t *task, int64_t delay) {
+	fastd_task_reschedule(task, task->entry.value + delay);
+}
+
+static inline void fastd_task_schedule(fastd_task_t *task, fastd_task_type_t type, fastd_timeout_t timeout) {
+	task->type = type;
+	fastd_task_reschedule(task, timeout);
+}
+
+
+bool fastd_task_timeout(fastd_timeout_t *timeout);
diff --git a/src/types.h b/src/types.h
index d5c8719..5ba6481 100644
--- a/src/types.h
+++ b/src/types.h
@@ -85,6 +85,13 @@ typedef enum fastd_poll_type {
 	POLL_TYPE_SOCKET,	/**< A network socket */
 } fastd_poll_type_t;
 
+/** Task types */
+typedef enum fastd_task_type {
+	TASK_TYPE_UNSPEC = 0,	/**< Unspecified task type */
+	TASK_TYPE_MAINTENANCE,	/**< Scheduled maintenance */
+	TASK_TYPE_HANDSHAKE,	/**< Scheduled handshake */
+} fastd_task_type_t;
+
 
 /** A timestamp used as a timeout */
 typedef int64_t fastd_timeout_t;
@@ -93,6 +100,7 @@ typedef int64_t fastd_timeout_t;
 typedef struct fastd_buffer fastd_buffer_t;
 typedef struct fastd_poll_fd fastd_poll_fd_t;
 typedef struct fastd_pqueue fastd_pqueue_t;
+typedef struct fastd_task fastd_task_t;
 
 typedef union fastd_peer_address fastd_peer_address_t;
 typedef struct fastd_bind_address fastd_bind_address_t;