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-rw-r--r--libevent-example.c97
1 files changed, 97 insertions, 0 deletions
diff --git a/libevent-example.c b/libevent-example.c
new file mode 100644
index 0000000..1f49d29
--- /dev/null
+++ b/libevent-example.c
@@ -0,0 +1,97 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <event.h>
+#include <string.h>
+#include "hiredis.h"
+
+#define NOT_USED(x) ((void)x)
+
+/* This struct enables us to pass both the event and the
+ * redisContext to the read and write handlers. */
+typedef struct redisEvents {
+ redisContext *context;
+ struct event read;
+ struct event write;
+} redisEvents;
+
+void redisLibEventRead(int fd, short event, void *arg) {
+ NOT_USED(fd); NOT_USED(event);
+ redisEvents *re = arg;
+
+ /* Always re-schedule read events */
+ event_add(&re->read,NULL);
+
+ if (redisBufferRead(re->context) == REDIS_ERR) {
+ /* Handle error. */
+ printf("Read error: %s\n", re->context->error);
+ } else {
+ /* Check replies. */
+ redisProcessCallbacks(re->context);
+ }
+}
+
+void redisLibEventWrite(int fd, short event, void *arg) {
+ NOT_USED(fd); NOT_USED(event);
+ redisEvents *re = arg;
+ int done = 0;
+
+ if (redisBufferWrite(re->context, &done) == REDIS_ERR) {
+ /* Handle error */
+ printf("Write error: %s\n", re->context->error);
+ } else {
+ /* Schedule write event again when writing is not done. */
+ if (!done) {
+ event_add(&re->write,NULL);
+ } else {
+ event_add(&re->read,NULL);
+ }
+ }
+}
+
+/* Schedule to be notified on a write event, so the outgoing buffer
+ * can be flushed to the socket. */
+void redisLibEventOnWrite(redisContext *c, void *privdata) {
+ NOT_USED(c);
+ redisEvents *e = privdata;
+ event_add(&e->write,NULL);
+}
+
+/* Free the redisEvents struct when the context is free'd. */
+void redisLibEventOnFree(redisContext *c, void *privdata) {
+ NOT_USED(c);
+ redisEvents *e = privdata;
+ free(e);
+}
+
+redisContext *redisLibEventConnect(const char *ip, int port) {
+ redisEvents *e = malloc(sizeof(*e));
+ e->context = redisConnectNonBlock(ip, port, NULL);
+ redisSetCommandCallback(e->context, redisLibEventOnWrite, e);
+ redisSetFreeCallback(e->context, redisLibEventOnFree, e);
+ event_set(&e->read, e->context->fd, EV_READ, redisLibEventRead, e);
+ event_set(&e->write, e->context->fd, EV_WRITE, redisLibEventWrite, e);
+ return e->context;
+}
+
+void getCallback(redisContext *c, redisReply *reply, void *privdata) {
+ NOT_USED(c); NOT_USED(privdata);
+ printf("argv[end-1]: %s\n", reply->reply);
+ redisFree(c);
+ exit(0);
+}
+
+int main (int argc, char **argv) {
+ signal(SIGPIPE, SIG_IGN);
+ event_init();
+
+ redisContext *c = redisLibEventConnect("127.0.0.1", 6379);
+ if (c->error != NULL) {
+ printf("Connect error: %s\n", c->error);
+ return 1;
+ }
+
+ redisCommand(c, "SET key %b", argv[argc-1], strlen(argv[argc-1]));
+ redisCommandWithCallback(c, getCallback, NULL, "GET key");
+ event_dispatch();
+ return 0;
+}