hiredis/libevent-example.c
2010-10-06 21:23:03 +02:00

97 lines
2.7 KiB
C

#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 rev, wev;
} redisEvents;
void redisLibEventRead(int fd, short event, void *arg) {
NOT_USED(fd); NOT_USED(event);
redisEvents *e = arg;
/* Always re-schedule read events */
event_add(&e->rev,NULL);
if (redisBufferRead(e->context) == REDIS_ERR) {
/* Handle error. */
printf("Read error: %s\n", e->context->error);
} else {
/* Check replies. */
redisProcessCallbacks(e->context);
}
}
void redisLibEventWrite(int fd, short event, void *arg) {
NOT_USED(fd); NOT_USED(event);
redisEvents *e = arg;
int done = 0;
if (redisBufferWrite(e->context, &done) == REDIS_ERR) {
/* Handle error */
printf("Write error: %s\n", e->context->error);
} else {
/* Schedule write event again when writing is not done. */
if (!done) {
event_add(&e->wev,NULL);
} else {
event_add(&e->rev,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->wev,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->rev, e->context->fd, EV_READ, redisLibEventRead, e);
event_set(&e->wev, 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("Connection 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;
}