daemon: timeout structure for IO.

For better or worse, the ccan/timer structure is completely minimal,
and designed to be wrapped inside a container structure.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

daemon/Makefile

@@ -11,7 +11,8 @@ DAEMON_SRC :=					\
 	daemon/json.c				\
 	daemon/lightningd.c			\
 	daemon/log.c				\
-	daemon/pseudorand.c
+	daemon/pseudorand.c			\
+	daemon/timeout.c
 DAEMON_OBJS := $(DAEMON_SRC:.c=.o)
 
 DAEMON_JSMN_OBJS := daemon/jsmn.o
@@ -22,7 +23,8 @@ DAEMON_HEADERS :=				\
 	daemon/json.h				\
 	daemon/lightningd.h			\
 	daemon/log.h				\
-	daemon/pseudorand.h
+	daemon/pseudorand.h			\
+	daemon/timeout.h
 
 $(DAEMON_OBJS): $(DAEMON_HEADERS) $(DAEMON_JSMN_HEADERS) $(BITCOIN_HEADERS) $(CORE_HEADERS) $(GEN_HEADERS) $(CCAN_HEADERS)
 $(DAEMON_JSMN_OBJS): $(DAEMON_JSMN_HEADERS)

daemon/lightningd.c

@@ -20,6 +20,7 @@ static struct lightningd_state *lightningd_state(void)
 	state->base_log = new_log(state, state->log_record,
 				  "lightningd(%u):", (int)getpid());
 
+	timers_init(&state->timers, time_now());
 	return state;
 }
 

daemon/lightningd.h

@@ -1,6 +1,7 @@
 #ifndef LIGHTNING_DAEMON_LIGHTNING_H
 #define LIGHTNING_DAEMON_LIGHTNING_H
 #include "config.h"
+#include <ccan/timer/timer.h>
 #include <stdio.h>
 
 /* Here's where the global variables hide! */
@@ -13,5 +14,8 @@ struct lightningd_state {
 	/* Our config dir, and rpc file */
 	char *config_dir;
 	char *rpc_filename;
+
+	/* Any pending timers. */
+	struct timers timers;	
 };
 #endif /* LIGHTNING_DAEMON_LIGHTNING_H */

daemon/timeout.c

@@ -0,0 +1,18 @@
+#include "lightningd.h"
+#include "timeout.h"
+
+void init_timeout_(struct timeout *t, unsigned int interval,
+		   void (*cb)(void *), void *arg)
+{
+	timer_init(&t->timer);
+	t->interval = time_from_sec(interval);
+	t->cb = cb;
+	t->arg = arg;
+}
+ 
+void refresh_timeout(struct lightningd_state *state, struct timeout *t)
+{
+	timer_del(&state->timers, &t->timer);
+	timer_add(&state->timers, &t->timer,
+		  timeabs_add(time_now(), t->interval));
+}

daemon/timeout.h

@@ -0,0 +1,27 @@
+#ifndef LIGHTNING_DAEMON_TIMEOUT_H
+#define LIGHTNING_DAEMON_TIMEOUT_H
+#include "config.h"
+
+#include <ccan/time/time.h>
+#include <ccan/timer/timer.h>
+#include <ccan/typesafe_cb/typesafe_cb.h>
+
+struct timeout {
+	struct timer timer;
+	struct timerel interval;
+	void (*cb)(void *);
+	void *arg;
+};
+
+struct lightningd_state;
+
+void init_timeout_(struct timeout *t, unsigned int interval,
+		   void (*cb)(void *), void *arg);
+ 
+void refresh_timeout(struct lightningd_state *state, struct timeout *t);
+
+#define init_timeout(t, interval, func, arg)				\
+	init_timeout_((t), (interval),					\
+		     typesafe_cb(void, void *, (func), (arg)), (arg))
+
+#endif /* LIGHTNING_DAEMON_TIMEOUT_H */