Redis的Client设计

最新推荐文章于 2022-07-05 21:12:09 发布

Daemon_1994

最新推荐文章于 2022-07-05 21:12:09 发布

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Redis的client设计如下：

/* With multiplexing we need to take per-clinet state.
 * Clients are taken in a liked list. */
typedef struct redisClient {
  int fd;
  redisDb *db;
  int dictid;
  sds querybuf;
  robj **argv, **mbargv;
  int argc, mbargc;
  int bulklen;			/* bulk read len. -1 if not in bulk read mode */
  int multibulk;		  /* multi bulk command format active */
  list *reply;
  int sentlen;
  time_t lastinteraction; /* time of the last interaction, used for timeout */
  int flags;			  /* REDIS_CLOSE | REDIS_SLAVE | REDIS_MONITOR */
  int slaveseldb;		 /* slave selected db, if this client is a slave */
  int authenticated;	  /* when requirepass is non-NULL */
  int replstate;		  /* replication state if this is a slave */
  int repldbfd;		   /* replication DB file descriptor */
  long repldboff;		  /* replication DB file offset */
  off_t repldbsize;	   /* replication DB file size */
} redisClient;

在accpet后，开始创建一个client。

代码如下：

static client createClient(void) {
  client c = zmalloc(sizeof(struct _client));
  char err[ANET_ERR_LEN];

  c->fd = anetTcpNonBlockConnect(err,config.hostip,config.hostport);
  if (c->fd == ANET_ERR) {
    zfree(c);
    fprintf(stderr,"Connect: %s\n",err);
    return NULL;
  }
  anetTcpNoDelay(NULL,c->fd);
  c->obuf = sdsempty();
  c->ibuf = sdsempty();
  c->mbulk = -1;
  c->readlen = 0;
  c->written = 0;
  c->totreceived = 0;
  c->state = CLIENT_CONNECTING;
  aeCreateFileEvent(config.el, c->fd, AE_WRITABLE, writeHandler, c);
  config.liveclients++;
  listAddNodeTail(config.clients,c);
  return c;
}