1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
|
#include <sys/types.h>
#include <event.h>
#include <hiredis.h>
/* Prototype for the error callback. */
typedef void (redisErrorCallback)(const redisContext*);
typedef struct libeventRedisEvents {
redisContext *context;
redisErrorCallback *err;
struct event rev, wev;
} libeventRedisEvents;
void libeventRedisReadEvent(int fd, short event, void *arg) {
((void)fd); ((void)event);
libeventRedisEvents *e = arg;
/* Always re-schedule read events */
event_add(&e->rev,NULL);
if (redisBufferRead(e->context) == REDIS_ERR) {
e->err(e->context);
} else {
if (redisProcessCallbacks(e->context) == REDIS_ERR) {
e->err(e->context);
}
}
}
void libeventRedisWriteEvent(int fd, short event, void *arg) {
((void)fd); ((void)event);
libeventRedisEvents *e = arg;
int done = 0;
if (redisBufferWrite(e->context,&done) == REDIS_ERR) {
/* Handle error */
e->err(e->context);
} 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 libeventRedisCommandCallback(redisContext *c, void *privdata) {
((void)c);
libeventRedisEvents *e = privdata;
event_add(&e->wev,NULL);
}
/* Remove event handlers when the context gets disconnected. */
void libeventRedisDisconnectCallback(redisContext *c, void *privdata) {
((void)c);
libeventRedisEvents *e = privdata;
event_del(&e->rev);
event_del(&e->wev);
}
/* Free the libeventRedisEvents struct when the context is free'd. */
void libeventRedisFreeCallback(redisContext *c, void *privdata) {
((void)c);
libeventRedisEvents *e = privdata;
free(e);
}
redisContext *libeventRedisConnect(struct event_base *base, redisErrorCallback *err, const char *ip, int port) {
libeventRedisEvents *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->context = c;
e->err = err;
/* Register callbacks */
redisSetDisconnectCallback(c,libeventRedisDisconnectCallback,e);
redisSetCommandCallback(c,libeventRedisCommandCallback,e);
redisSetFreeCallback(c,libeventRedisFreeCallback,e);
/* Initialize and install read/write events */
event_set(&e->rev,c->fd,EV_READ,libeventRedisReadEvent,e);
event_set(&e->wev,c->fd,EV_WRITE,libeventRedisWriteEvent,e);
event_base_set(base,&e->rev);
event_base_set(base,&e->wev);
return c;
}
|