From 5b82660a774380994b5273008c3dbdf657273e50 Mon Sep 17 00:00:00 2001
From: Nicolas Favre-Felix <n.favrefelix@gmail.com>
Date: Fri, 24 Dec 2010 12:16:40 +0100
Subject: [PATCH] Scheduled reconnect.

---
 turnip.c | 92 +++++++++++++++++++++++++++++++++++---------------------
 1 file changed, 58 insertions(+), 34 deletions(-)

diff --git a/turnip.c b/turnip.c
index 6e7613b..5cb4180 100644
--- a/turnip.c
+++ b/turnip.c
@@ -13,12 +13,49 @@
 
 #include "conf.h"
 #include "cmd.h"
+#include "turnip.h"
 
-static struct conf *cfg;
-redisAsyncContext *__redis_context = NULL;
-struct event_base *__base;
+struct turnip *__t = NULL;
+
+static void
+connectCallback(const redisAsyncContext *c);
+
+static void
+disconnectCallback(const redisAsyncContext *c, int status);
 
-static void reconnect();
+
+static void
+reconnect();
+
+static void
+on_timer_reconnect(int fd, short event, void *ctx) {
+
+	(void)fd;
+	(void)event;
+	(void)ctx;
+
+	if(__t->ac) {
+		redisLibeventCleanup(__t->ac->_adapter_data);
+	}
+
+	/* TODO: free AC. */
+
+	if(__t->cfg->redis_host[0] == '/') { /* unix socket */
+		__t->ac = redisAsyncConnectUnix(__t->cfg->redis_host);
+	} else {
+		__t->ac = redisAsyncConnect(__t->cfg->redis_host, __t->cfg->redis_port);
+	}
+	if(__t->ac->err) {
+		/* Let *c leak for now... */
+		printf("Error: %s\n", __t->ac->errstr);
+	}
+
+
+	redisLibeventAttach(__t->ac, __t->base);
+	redisAsyncSetConnectCallback(__t->ac, connectCallback);
+	redisAsyncSetDisconnectCallback(__t->ac, disconnectCallback);
+
+}
 
 static void
 connectCallback(const redisAsyncContext *c) {
@@ -31,34 +68,20 @@ disconnectCallback(const redisAsyncContext *c, int status) {
 	if (status != REDIS_OK) {
 		printf("Error: %s\n", c->errstr);
 	}
-	printf("disconnected...\n");
-	__redis_context = NULL;
+	printf("disconnected, schedule reconnect.\n");
+	__t->ac = NULL;
 
-	/* TODO: schedule reconnect instead to avoid opening too many sockets */
 	reconnect();
 }
 
 static void
 reconnect() {
-
-	if(__redis_context) {
-		redisLibeventCleanup(__redis_context->_adapter_data);
-	}
-
-	if(cfg->redis_host[0] == '/') { /* unix socket */
-		__redis_context = redisAsyncConnectUnix(cfg->redis_host);
-	} else {
-		__redis_context = redisAsyncConnect(cfg->redis_host, cfg->redis_port);
-	}
-	if(__redis_context->err) {
-		/* Let *c leak for now... */
-		printf("Error: %s\n", __redis_context->errstr);
-	}
-
-
-	redisLibeventAttach(__redis_context, __base);
-	redisAsyncSetConnectCallback(__redis_context, connectCallback);
-	redisAsyncSetDisconnectCallback(__redis_context, disconnectCallback);
+	/* schedule reconnect */
+	evtimer_set(&__t->ev_reconnect, on_timer_reconnect, NULL);
+	event_base_set(__t->base, &__t->ev_reconnect);
+	__t->tv_reconnect.tv_sec = 1;
+	__t->tv_reconnect.tv_usec = 0;
+	evtimer_add(&__t->ev_reconnect, &__t->tv_reconnect);
 }
 
 void
@@ -67,18 +90,18 @@ on_request(struct evhttp_request *rq, void *ctx) {
 	const char *uri = evhttp_request_uri(rq);
 	(void)ctx;
 
-	if(!__redis_context) { /* redis is unavailable */
+	if(!__t->ac) { /* redis is unavailable */
 		evhttp_send_reply(rq, 503, "Service Unavailable", NULL);
 		return;
 	}
 
 	switch(rq->type) {
 		case EVHTTP_REQ_GET:
-			cmd_run(__redis_context, rq, 1+uri, strlen(uri)-1);
+			cmd_run(__t->ac, rq, 1+uri, strlen(uri)-1);
 			break;
 
 		case EVHTTP_REQ_POST:
-			cmd_run(__redis_context, rq,
+			cmd_run(__t->ac, rq,
 				(const char*)EVBUFFER_DATA(rq->input_buffer),
 				EVBUFFER_LENGTH(rq->input_buffer));
 			break;
@@ -94,10 +117,11 @@ main(int argc, char *argv[]) {
 	(void)argc;
 	(void)argv;
 
-	__base = event_base_new();
-	struct evhttp *http = evhttp_new(__base);
+	__t = calloc(1, sizeof(struct turnip));
+	__t->base = event_base_new();
+	struct evhttp *http = evhttp_new(__t->base);
 	
-	cfg = conf_read("turnip.conf");
+	__t->cfg = conf_read("turnip.conf");
 
 	/* ignore sigpipe */
 #ifdef SIGPIPE
@@ -105,14 +129,14 @@ main(int argc, char *argv[]) {
 #endif
 
 	/* start http server */
-	evhttp_bind_socket(http, cfg->http_host, cfg->http_port);
+	evhttp_bind_socket(http, __t->cfg->http_host, __t->cfg->http_port);
 	evhttp_set_gencb(http, on_request, NULL);
 
 	/* attach hiredis to libevent base */
 	reconnect();
 
 	/* loop */
-	event_base_dispatch(__base);
+	event_base_dispatch(__t->base);
 
 	return EXIT_SUCCESS;
 }