From e245ab48ec8f766e589771b976761a0a41b6442d Mon Sep 17 00:00:00 2001
From: Pieter Noordhuis <pcnoordhuis@gmail.com>
Date: Tue, 19 Oct 2010 17:10:01 +0200
Subject: [PATCH] Added header file and example for usage from libev

---
 .gitignore            |  2 +-
 Makefile              |  5 ++-
 extra/hiredis/libev.h | 90 +++++++++++++++++++++++++++++++++++++++++++
 libev-example.c       | 30 +++++++++++++++
 4 files changed, 125 insertions(+), 2 deletions(-)
 create mode 100644 extra/hiredis/libev.h
 create mode 100644 libev-example.c

diff --git a/.gitignore b/.gitignore
index 30e67d9..14bd58c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,6 @@
 /hiredis-test
 /hiredis-example
-/libevent-example
+/*-example
 /*.o
 /*.so
 /*.dylib
diff --git a/Makefile b/Makefile
index d3d4f28..3c1b651 100644
--- a/Makefile
+++ b/Makefile
@@ -61,11 +61,14 @@ test: hiredis-test
 libevent-example: extra/hiredis/libevent.h libevent-example.c ${DYLIBNAME}
 	$(CC) -o $@ $(CCOPT) $(DEBUG) -I. -Iextra -L. -lhiredis -levent libevent-example.c
 
+libev-example: extra/hiredis/libev.h libev-example.c ${DYLIBNAME}
+	$(CC) -o $@ $(CCOPT) $(DEBUG) -I. -Iextra -L. -lhiredis -lev libev-example.c
+
 .c.o:
 	$(CC) -c $(CFLAGS) $(DEBUG) $(COMPILE_TIME) $<
 
 clean:
-	rm -rf ${DYLIBNAME} ${STLIBNAME} $(BINS) libevent-example *.o *.gcda *.gcno *.gcov
+	rm -rf ${DYLIBNAME} ${STLIBNAME} $(BINS) *-example *.o *.gcda *.gcno *.gcov
 
 dep:
 	$(CC) -MM *.c
diff --git a/extra/hiredis/libev.h b/extra/hiredis/libev.h
new file mode 100644
index 0000000..79dde42
--- /dev/null
+++ b/extra/hiredis/libev.h
@@ -0,0 +1,90 @@
+#include <sys/types.h>
+#include <ev.h>
+#include <hiredis.h>
+
+/* Prototype for the error callback. */
+typedef void (redisErrorCallback)(const redisContext*);
+
+typedef struct libevRedisEvents {
+    redisContext *context;
+    redisErrorCallback *err;
+    struct ev_loop *loop;
+    ev_io rev, wev;
+} libevRedisEvents;
+
+void libevRedisReadEvent(struct ev_loop *loop, ev_io *watcher, int revents) {
+    ((void)loop); ((void)revents);
+    libevRedisEvents *e = watcher->data;
+
+    if (redisBufferRead(e->context) == REDIS_ERR) {
+        e->err(e->context);
+    } else {
+        if (redisProcessCallbacks(e->context) == REDIS_ERR) {
+            e->err(e->context);
+        }
+    }
+}
+
+void libevRedisWriteEvent(struct ev_loop *loop, ev_io *watcher, int revents) {
+    ((void)loop); ((void)revents);
+    libevRedisEvents *e = watcher->data;
+    int done = 0;
+
+    if (redisBufferWrite(e->context, &done) == REDIS_ERR) {
+        ev_io_stop(e->loop,&e->wev);
+        e->err(e->context);
+    } else {
+        /* Stop firing the write event when done */
+        if (done) {
+            ev_io_stop(e->loop,&e->wev);
+            ev_io_start(e->loop,&e->rev);
+        }
+    }
+}
+
+void libevRedisCommandCallback(redisContext *c, void *privdata) {
+    ((void)c);
+    libevRedisEvents *e = privdata;
+    ev_io_start(e->loop,&e->wev);
+}
+
+void libevRedisDisconnectCallback(redisContext *c, void *privdata) {
+    ((void)c);
+    libevRedisEvents *e = privdata;
+    ev_io_stop(e->loop,&e->rev);
+    ev_io_stop(e->loop,&e->wev);
+}
+
+void libevRedisFreeCallback(redisContext *c, void *privdata) {
+    ((void)c);
+    libevRedisEvents *e = privdata;
+    free(e);
+}
+
+redisContext *libevRedisConnect(struct ev_loop *loop, redisErrorCallback *err, const char *ip, int port) {
+    libevRedisEvents *e;
+    redisContext *c = redisConnectNonBlock(ip, port, NULL);
+    if (c->error != NULL) {
+        err(c);
+        redisFree(c);
+        return NULL;
+    }
+
+    /* Create container for context and r/w events */
+    e = malloc(sizeof(*e));
+    e->loop = loop;
+    e->context = c;
+    e->err = err;
+    e->rev.data = e;
+    e->wev.data = e;
+
+    /* Register callbacks */
+    redisSetDisconnectCallback(c,libevRedisDisconnectCallback,e);
+    redisSetCommandCallback(c,libevRedisCommandCallback,e);
+    redisSetFreeCallback(c,libevRedisFreeCallback,e);
+
+    /* Initialize read/write events */
+    ev_io_init(&e->rev,libevRedisReadEvent,c->fd,EV_READ);
+    ev_io_init(&e->wev,libevRedisWriteEvent,c->fd,EV_WRITE);
+    return c;
+}
diff --git a/libev-example.c b/libev-example.c
new file mode 100644
index 0000000..8c48121
--- /dev/null
+++ b/libev-example.c
@@ -0,0 +1,30 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <hiredis/libev.h>
+#include <signal.h>
+
+void getCallback(redisContext *c, redisReply *reply, const void *privdata) {
+    printf("argv[%s]: %s\n", (const char*)privdata, reply->reply);
+
+    /* Disconnect after receiving the reply to GET */
+    redisDisconnect(c);
+}
+
+void errorCallback(const redisContext *c) {
+    printf("Error: %s\n", c->error);
+}
+
+int main (int argc, char **argv) {
+    signal(SIGPIPE, SIG_IGN);
+    struct ev_loop *loop = ev_default_loop(0);
+
+    redisContext *c = libevRedisConnect(loop, errorCallback, "127.0.0.1", 6379);
+    if (c == NULL) return 1;
+
+    redisCommand(c, "SET key %b", argv[argc-1], strlen(argv[argc-1]));
+    redisCommandWithCallback(c, getCallback, "end-1", "GET key");
+    ev_loop(loop, 0);
+    redisFree(c);
+    return 0;
+}