*/
#include <string.h>
+#include <strings.h>
#include <assert.h>
+#include <ctype.h>
#include "async.h"
+#include "dict.c"
#include "sds.h"
#include "util.h"
/* Forward declaration of function in hiredis.c */
void __redisAppendCommand(redisContext *c, char *cmd, size_t len);
+/* Functions managing dictionary of callbacks for pub/sub. */
+static unsigned int callbackHash(const void *key) {
+ return dictGenHashFunction((unsigned char*)key,sdslen((char*)key));
+}
+
+static void *callbackValDup(void *privdata, const void *src) {
+ ((void) privdata);
+ redisCallback *dup = malloc(sizeof(*dup));
+ memcpy(dup,src,sizeof(*dup));
+ return dup;
+}
+
+static int callbackKeyCompare(void *privdata, const void *key1, const void *key2) {
+ int l1, l2;
+ ((void) privdata);
+
+ l1 = sdslen((sds)key1);
+ l2 = sdslen((sds)key2);
+ if (l1 != l2) return 0;
+ return memcmp(key1,key2,l1) == 0;
+}
+
+static void callbackKeyDestructor(void *privdata, void *key) {
+ ((void) privdata);
+ sdsfree((sds)key);
+}
+
+static void callbackValDestructor(void *privdata, void *val) {
+ ((void) privdata);
+ free(val);
+}
+
+static dictType callbackDict = {
+ callbackHash,
+ NULL,
+ callbackValDup,
+ callbackKeyCompare,
+ callbackKeyDestructor,
+ callbackValDestructor
+};
+
static redisAsyncContext *redisAsyncInitialize(redisContext *c) {
redisAsyncContext *ac = realloc(c,sizeof(redisAsyncContext));
c = &(ac->c);
ac->err = 0;
ac->errstr = NULL;
ac->data = NULL;
- ac->_adapter_data = NULL;
- ac->evAddRead = NULL;
- ac->evDelRead = NULL;
- ac->evAddWrite = NULL;
- ac->evDelWrite = NULL;
- ac->evCleanup = NULL;
+ ac->ev.data = NULL;
+ ac->ev.addRead = NULL;
+ ac->ev.delRead = NULL;
+ ac->ev.addWrite = NULL;
+ ac->ev.delWrite = NULL;
+ ac->ev.cleanup = NULL;
ac->onConnect = NULL;
ac->onDisconnect = NULL;
ac->replies.head = NULL;
ac->replies.tail = NULL;
+ ac->sub.invalid.head = NULL;
+ ac->sub.invalid.tail = NULL;
+ ac->sub.channels = dictCreate(&callbackDict,NULL);
+ ac->sub.patterns = dictCreate(&callbackDict,NULL);
return ac;
}
int redisAsyncSetConnectCallback(redisAsyncContext *ac, redisConnectCallback *fn) {
if (ac->onConnect == NULL) {
ac->onConnect = fn;
+
+ /* The common way to detect an established connection is to wait for
+ * the first write event to be fired. This assumes the related event
+ * library functions are already set. */
+ if (ac->ev.addWrite) ac->ev.addWrite(ac->ev.data);
return REDIS_OK;
}
return REDIS_ERR;
redisCallback *cb;
/* Copy callback from stack to heap */
- cb = calloc(1,sizeof(*cb));
+ cb = malloc(sizeof(*cb));
if (!cb) redisOOM();
if (source != NULL) {
- cb->fn = source->fn;
- cb->privdata = source->privdata;
+ memcpy(cb,source,sizeof(*cb));
+ cb->next = NULL;
}
/* Store callback in list */
return REDIS_ERR;
}
-/* Tries to do a clean disconnect from Redis, meaning it stops new commands
- * from being issued, but tries to flush the output buffer and execute
- * callbacks for all remaining replies.
- *
- * This functions is generally called from within a callback, so the
- * processCallbacks function will pick up the flag when there are no
- * more replies. */
-void redisAsyncDisconnect(redisAsyncContext *ac) {
+static void __redisRunCallback(redisAsyncContext *ac, redisCallback *cb, redisReply *reply) {
redisContext *c = &(ac->c);
- c->flags |= REDIS_DISCONNECTING;
+ if (cb->fn != NULL) {
+ c->flags |= REDIS_IN_CALLBACK;
+ cb->fn(ac,reply,cb->privdata);
+ c->flags &= ~REDIS_IN_CALLBACK;
+ }
+}
+
+/* Helper function to free the context. */
+static void __redisAsyncFree(redisAsyncContext *ac) {
+ redisContext *c = &(ac->c);
+ redisCallback cb;
+ dictIterator *it;
+ dictEntry *de;
+
+ /* Execute pending callbacks with NULL reply. */
+ while (__redisShiftCallback(&ac->replies,&cb) == REDIS_OK)
+ __redisRunCallback(ac,&cb,NULL);
+
+ /* Execute callbacks for invalid commands */
+ while (__redisShiftCallback(&ac->sub.invalid,&cb) == REDIS_OK)
+ __redisRunCallback(ac,&cb,NULL);
+
+ /* Run subscription callbacks callbacks with NULL reply */
+ it = dictGetIterator(ac->sub.channels);
+ while ((de = dictNext(it)) != NULL)
+ __redisRunCallback(ac,dictGetEntryVal(de),NULL);
+ dictReleaseIterator(it);
+ dictRelease(ac->sub.channels);
+
+ it = dictGetIterator(ac->sub.patterns);
+ while ((de = dictNext(it)) != NULL)
+ __redisRunCallback(ac,dictGetEntryVal(de),NULL);
+ dictReleaseIterator(it);
+ dictRelease(ac->sub.patterns);
+
+ /* Signal event lib to clean up */
+ if (ac->ev.cleanup) ac->ev.cleanup(ac->ev.data);
+
+ /* Execute disconnect callback. When redisAsyncFree() initiated destroying
+ * this context, the status will always be REDIS_OK. */
+ if (ac->onDisconnect && (c->flags & REDIS_CONNECTED)) {
+ if (c->flags & REDIS_FREEING) {
+ ac->onDisconnect(ac,REDIS_OK);
+ } else {
+ ac->onDisconnect(ac,(ac->err == 0) ? REDIS_OK : REDIS_ERR);
+ }
+ }
+
+ /* Cleanup self */
+ redisFree(c);
+}
+
+/* Free the async context. When this function is called from a callback,
+ * control needs to be returned to redisProcessCallbacks() before actual
+ * free'ing. To do so, a flag is set on the context which is picked up by
+ * redisProcessCallbacks(). Otherwise, the context is immediately free'd. */
+void redisAsyncFree(redisAsyncContext *ac) {
+ redisContext *c = &(ac->c);
+ c->flags |= REDIS_FREEING;
+ if (!(c->flags & REDIS_IN_CALLBACK))
+ __redisAsyncFree(ac);
}
/* Helper function to make the disconnect happen and clean up. */
static void __redisAsyncDisconnect(redisAsyncContext *ac) {
redisContext *c = &(ac->c);
- redisCallback cb;
- int status;
/* Make sure error is accessible if there is any */
__redisAsyncCopyError(ac);
- status = (ac->err == 0) ? REDIS_OK : REDIS_ERR;
- if (status == REDIS_OK) {
- /* When the connection is cleanly disconnected, there should not
- * be pending callbacks. */
+ if (ac->err == 0) {
+ /* For clean disconnects, there should be no pending callbacks. */
assert(__redisShiftCallback(&ac->replies,NULL) == REDIS_ERR);
} else {
- /* Callbacks should not be able to issue new commands. */
+ /* Disconnection is caused by an error, make sure that pending
+ * callbacks cannot call new commands. */
c->flags |= REDIS_DISCONNECTING;
-
- /* Execute pending callbacks with NULL reply. */
- while (__redisShiftCallback(&ac->replies,&cb) == REDIS_OK) {
- if (cb.fn != NULL)
- cb.fn(ac,NULL,cb.privdata);
- }
}
- /* Signal event lib to clean up */
- if (ac->evCleanup) ac->evCleanup(ac->_adapter_data);
+ /* For non-clean disconnects, __redisAsyncFree() will execute pending
+ * callbacks with a NULL-reply. */
+ __redisAsyncFree(ac);
+}
- /* Execute callback with proper status */
- if (ac->onDisconnect) ac->onDisconnect(ac,status);
+/* Tries to do a clean disconnect from Redis, meaning it stops new commands
+ * from being issued, but tries to flush the output buffer and execute
+ * callbacks for all remaining replies. When this function is called from a
+ * callback, there might be more replies and we can safely defer disconnecting
+ * to redisProcessCallbacks(). Otherwise, we can only disconnect immediately
+ * when there are no pending callbacks. */
+void redisAsyncDisconnect(redisAsyncContext *ac) {
+ redisContext *c = &(ac->c);
+ c->flags |= REDIS_DISCONNECTING;
+ if (!(c->flags & REDIS_IN_CALLBACK) && ac->replies.head == NULL)
+ __redisAsyncDisconnect(ac);
+}
- /* Cleanup self */
- redisFree(c);
+static int __redisGetSubscribeCallback(redisAsyncContext *ac, redisReply *reply, redisCallback *dstcb) {
+ redisContext *c = &(ac->c);
+ dict *callbacks;
+ dictEntry *de;
+ int pvariant;
+ char *stype;
+ sds sname;
+
+ /* Custom reply functions are not supported for pub/sub. This will fail
+ * very hard when they are used... */
+ if (reply->type == REDIS_REPLY_ARRAY) {
+ assert(reply->elements >= 2);
+ assert(reply->element[0]->type == REDIS_REPLY_STRING);
+ stype = reply->element[0]->str;
+ pvariant = (tolower(stype[0]) == 'p') ? 1 : 0;
+
+ if (pvariant)
+ callbacks = ac->sub.patterns;
+ else
+ callbacks = ac->sub.channels;
+
+ /* Locate the right callback */
+ assert(reply->element[1]->type == REDIS_REPLY_STRING);
+ sname = sdsnewlen(reply->element[1]->str,reply->element[1]->len);
+ de = dictFind(callbacks,sname);
+ if (de != NULL) {
+ memcpy(dstcb,dictGetEntryVal(de),sizeof(*dstcb));
+
+ /* If this is an unsubscribe message, remove it. */
+ if (strcasecmp(stype+pvariant,"unsubscribe") == 0) {
+ dictDelete(callbacks,sname);
+
+ /* If this was the last unsubscribe message, revert to
+ * non-subscribe mode. */
+ assert(reply->element[2]->type == REDIS_REPLY_INTEGER);
+ if (reply->element[2]->integer == 0)
+ c->flags &= ~REDIS_SUBSCRIBED;
+ }
+ }
+ sdsfree(sname);
+ } else {
+ /* Shift callback for invalid commands. */
+ __redisShiftCallback(&ac->sub.invalid,dstcb);
+ }
+ return REDIS_OK;
}
void redisProcessCallbacks(redisAsyncContext *ac) {
break;
}
- /* Shift callback and execute it */
- assert(__redisShiftCallback(&ac->replies,&cb) == REDIS_OK);
+ /* Even if the context is subscribed, pending regular callbacks will
+ * get a reply before pub/sub messages arrive. */
+ if (__redisShiftCallback(&ac->replies,&cb) != REDIS_OK) {
+ /* No more regular callbacks, the context *must* be subscribed. */
+ assert(c->flags & REDIS_SUBSCRIBED);
+ __redisGetSubscribeCallback(ac,reply,&cb);
+ }
+
if (cb.fn != NULL) {
- cb.fn(ac,reply,cb.privdata);
+ __redisRunCallback(ac,&cb,reply);
+ c->fn->freeObject(reply);
+
+ /* Proceed with free'ing when redisAsyncFree() was called. */
+ if (c->flags & REDIS_FREEING) {
+ __redisAsyncFree(ac);
+ return;
+ }
} else {
+ /* No callback for this reply. This can either be a NULL callback,
+ * or there were no callbacks to begin with. Either way, don't
+ * abort with an error, but simply ignore it because the client
+ * doesn't know what the server will spit out over the wire. */
c->fn->freeObject(reply);
}
}
__redisAsyncDisconnect(ac);
} else {
/* Always re-schedule reads */
- if (ac->evAddRead) ac->evAddRead(ac->_adapter_data);
+ if (ac->ev.addRead) ac->ev.addRead(ac->ev.data);
redisProcessCallbacks(ac);
}
}
} else {
/* Continue writing when not done, stop writing otherwise */
if (!done) {
- if (ac->evAddWrite) ac->evAddWrite(ac->_adapter_data);
+ if (ac->ev.addWrite) ac->ev.addWrite(ac->ev.data);
} else {
- if (ac->evDelWrite) ac->evDelWrite(ac->_adapter_data);
+ if (ac->ev.delWrite) ac->ev.delWrite(ac->ev.data);
}
/* Always schedule reads after writes */
- if (ac->evAddRead) ac->evAddRead(ac->_adapter_data);
+ if (ac->ev.addRead) ac->ev.addRead(ac->ev.data);
/* Fire onConnect when this is the first write event. */
if (!(c->flags & REDIS_CONNECTED)) {
}
}
-/* Helper function for the redisAsyncCommand* family of functions.
- *
- * Write a formatted command to the output buffer and register the provided
- * callback function with the context.
- */
+/* Sets a pointer to the first argument and its length starting at p. Returns
+ * the number of bytes to skip to get to the following argument. */
+static char *nextArgument(char *start, char **str, size_t *len) {
+ char *p = start;
+ if (p[0] != '$') {
+ p = strchr(p,'$');
+ if (p == NULL) return NULL;
+ }
+
+ *len = (int)strtol(p+1,NULL,10);
+ p = strchr(p,'\r');
+ assert(p);
+ *str = p+2;
+ return p+2+(*len)+2;
+}
+
+/* Helper function for the redisAsyncCommand* family of functions. Writes a
+ * formatted command to the output buffer and registers the provided callback
+ * function with the context. */
static int __redisAsyncCommand(redisAsyncContext *ac, redisCallbackFn *fn, void *privdata, char *cmd, size_t len) {
redisContext *c = &(ac->c);
redisCallback cb;
+ int pvariant, hasnext;
+ char *cstr, *astr;
+ size_t clen, alen;
+ char *p;
+ sds sname;
- /* Don't accept new commands when the connection is lazily closed. */
- if (c->flags & REDIS_DISCONNECTING) return REDIS_ERR;
- __redisAppendCommand(c,cmd,len);
+ /* Don't accept new commands when the connection is about to be closed. */
+ if (c->flags & (REDIS_DISCONNECTING | REDIS_FREEING)) return REDIS_ERR;
- /* Store callback */
+ /* Setup callback */
cb.fn = fn;
cb.privdata = privdata;
- __redisPushCallback(&ac->replies,&cb);
+
+ /* Find out which command will be appended. */
+ p = nextArgument(cmd,&cstr,&clen);
+ assert(p != NULL);
+ hasnext = (p[0] == '$');
+ pvariant = (tolower(cstr[0]) == 'p') ? 1 : 0;
+ cstr += pvariant;
+ clen -= pvariant;
+
+ if (hasnext && strncasecmp(cstr,"subscribe\r\n",11) == 0) {
+ c->flags |= REDIS_SUBSCRIBED;
+
+ /* Add every channel/pattern to the list of subscription callbacks. */
+ while ((p = nextArgument(p,&astr,&alen)) != NULL) {
+ sname = sdsnewlen(astr,alen);
+ if (pvariant)
+ dictReplace(ac->sub.patterns,sname,&cb);
+ else
+ dictReplace(ac->sub.channels,sname,&cb);
+ }
+ } else if (strncasecmp(cstr,"unsubscribe\r\n",13) == 0) {
+ /* It is only useful to call (P)UNSUBSCRIBE when the context is
+ * subscribed to one or more channels or patterns. */
+ if (!(c->flags & REDIS_SUBSCRIBED)) return REDIS_ERR;
+
+ /* (P)UNSUBSCRIBE does not have its own response: every channel or
+ * pattern that is unsubscribed will receive a message. This means we
+ * should not append a callback function for this command. */
+ } else {
+ if (c->flags & REDIS_SUBSCRIBED)
+ /* This will likely result in an error reply, but it needs to be
+ * received and passed to the callback. */
+ __redisPushCallback(&ac->sub.invalid,&cb);
+ else
+ __redisPushCallback(&ac->replies,&cb);
+ }
+
+ __redisAppendCommand(c,cmd,len);
/* Always schedule a write when the write buffer is non-empty */
- if (ac->evAddWrite) ac->evAddWrite(ac->_adapter_data);
+ if (ac->ev.addWrite) ac->ev.addWrite(ac->ev.data);
return REDIS_OK;
}