daemon: dev-mocktime command

Useful for precise timing control for testing.

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

daemon/Makefile

@@ -15,6 +15,7 @@ DAEMON_LIB_OBJS := $(DAEMON_LIB_SRC:.c=.o)
 
 DAEMON_SRC :=					\
 	daemon/bitcoind.c			\
+	daemon/controlled_time.c		\
 	daemon/cryptopkt.c			\
 	daemon/dns.c				\
 	daemon/jsonrpc.c			\
@@ -39,6 +40,7 @@ DAEMON_JSMN_HEADERS := daemon/jsmn/jsmn.h
 DAEMON_HEADERS :=				\
 	daemon/bitcoind.h			\
 	daemon/configdir.h			\
+	daemon/controlled_time.h		\
 	daemon/cryptopkt.h			\
 	daemon/dns.h				\
 	daemon/json.h				\

daemon/controlled_time.c

@@ -0,0 +1,52 @@
+#include "controlled_time.h"
+#include "jsonrpc.h"
+#include "lightningd.h"
+#include "log.h"
+#include <inttypes.h>
+#include <stdio.h>
+
+static struct timeabs mock_time;
+
+struct timeabs controlled_time(void)
+{
+	if (mock_time.ts.tv_sec)
+		return mock_time;
+	return time_now();
+}
+
+static void json_mocktime(struct command *cmd,
+			  const char *buffer, const jsmntok_t *params)
+{
+	struct json_result *response = new_json_result(cmd);
+	jsmntok_t *mocktimetok;
+	u64 prev_time, mocktime;
+	char mocktimestr[STR_MAX_CHARS(int64_t)];
+
+	json_get_params(buffer, params,
+			"mocktime", &mocktimetok,
+			NULL);
+
+	prev_time = controlled_time().ts.tv_sec;
+	if (!mocktimetok || !json_tok_u64(buffer, mocktimetok, &mocktime)) {
+		command_fail(cmd, "Need valid mocktime");
+		return;
+	}
+	mock_time.ts.tv_sec = mocktime;
+
+	json_object_start(response, NULL);
+	sprintf(mocktimestr, "%"PRIi64,
+		(s64)controlled_time().ts.tv_sec - prev_time);
+	json_add_string(response, "offset", mocktimestr);
+	json_object_end(response);
+
+	log_unusual(cmd->dstate->base_log,
+		    "mocktime set to %"PRIu64, (u64)mock_time.ts.tv_sec);
+	command_success(cmd, response);
+}
+
+const struct json_command mocktime_command = {
+	"dev-mocktime",
+	json_mocktime,
+	"Set current time to {mocktime} seconds (0 to return to normal)",
+	"Returns the offset on success"
+};

daemon/controlled_time.h

@@ -0,0 +1,9 @@
+#ifndef LIGHTNING_DAEMON_CONTROLLED_TIME_H
+#define LIGHTNING_DAEMON_CONTROLLED_TIME_H
+#include "config.h"
+#include <ccan/short_types/short_types.h>
+#include <ccan/time/time.h>
+
+struct timeabs controlled_time(void);
+
+#endif /* LIGHTNING_DAEMON_CONTROLLED_TIME_H */

daemon/jsonrpc.c

@@ -244,6 +244,7 @@ static const struct json_command *cmdlist[] = {
 	/* Developer/debugging options. */
 	&echo_command,
 	&rhash_command,
+	&mocktime_command
 };
 
 static void json_help(struct command *cmd,

daemon/jsonrpc.h

@@ -61,4 +61,5 @@ extern const struct json_command getpeers_command;
 extern const struct json_command newhtlc_command;
 extern const struct json_command fulfillhtlc_command;
 extern const struct json_command failhtlc_command;
+extern const struct json_command mocktime_command;
 #endif /* LIGHTNING_DAEMON_JSONRPC_H */

daemon/lightning-cli.c

@@ -2,6 +2,7 @@
  * Helper to submit via JSON-RPC and get back response.
  */
 #include "configdir.h"
+#include "controlled_time.h"
 #include "json.h"
 #include "version.h"
 #include <ccan/err/err.h>
@@ -39,6 +40,11 @@ static void tal_freefn(void *ptr)
 	tal_free(ptr);
 }
 
+struct timeabs controlled_time(void)
+{
+	return time_now();
+}
+
 int main(int argc, char *argv[])
 {
 	int fd, i, off;

daemon/lightningd.c

@@ -1,5 +1,6 @@
 #include "bitcoind.h"
 #include "configdir.h"
+#include "controlled_time.h"
 #include "jsonrpc.h"
 #include "lightningd.h"
 #include "log.h"
@@ -147,7 +148,7 @@ static struct lightningd_state *lightningd_state(void)
 				   "lightningd(%u):", (int)getpid());
 
 	list_head_init(&dstate->peers);
-	timers_init(&dstate->timers, time_now());
+	timers_init(&dstate->timers, controlled_time());
 	txwatch_hash_init(&dstate->txwatches);
 	txowatch_hash_init(&dstate->txowatches);
 	dstate->secpctx = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY
@@ -240,6 +241,9 @@ int main(int argc, char *argv[])
 	/* Create timer to do watches. */
 	setup_watch_timer(dstate);
 
+	/* Make sure we use the artificially-controlled time for timers */
+	io_time_override(controlled_time);
+	
 	log_info(dstate->base_log, "Hello world!");
 
 	/* If io_loop returns NULL, either a timer expired, or all fds closed */

daemon/log.c

@@ -1,3 +1,4 @@
+#include "controlled_time.h"
 #include "log.h"
 #include "pseudorand.h"
 #include <ccan/array_size/array_size.h>
@@ -102,7 +103,7 @@ struct log_record *new_log_record(const tal_t *ctx,
 	lr->max_mem = max_mem;
 	lr->print = log_default_print;
 	lr->print_level = printlevel;
-	lr->init_time = time_now();
+	lr->init_time = controlled_time();
 	list_head_init(&lr->log);
 
 	return lr;
@@ -183,7 +184,7 @@ static struct log_entry *new_log_entry(struct log *log, enum log_level level)
 {
 	struct log_entry *l = tal(log->lr, struct log_entry);
 
-	l->time = time_now();
+	l->time = controlled_time();
 	l->level = level;
 	l->skipped = 0;
 	l->prefix = log->prefix;

daemon/timeout.c

@@ -1,3 +1,4 @@
+#include "controlled_time.h"
 #include "lightningd.h"
 #include "timeout.h"
 
@@ -14,7 +15,7 @@ void refresh_timeout(struct lightningd_state *dstate, struct timeout *t)
 {
 	timer_del(&dstate->timers, &t->timer);
 	timer_add(&dstate->timers, &t->timer,
-		  timeabs_add(time_now(), t->interval));
+		  timeabs_add(controlled_time(), t->interval));
 }
 
 /* FIXME: Make all timers one-shot! */