Change prototype of connect callback

This commit adds a status argument to the connect callback. It will be
called in the event of an unsuccessful connection as well, where the
status argument is set to REDIS_ERR. It is set to REDIS_OK otherwise.

async.c

@@ -34,7 +34,9 @@
 #include <strings.h>
 #include <assert.h>
 #include <ctype.h>
+#include <errno.h>
 #include "async.h"
+#include "net.h"
 #include "dict.c"
 #include "sds.h"
 
@@ -419,12 +421,43 @@ void redisProcessCallbacks(redisAsyncContext *ac) {
         __redisAsyncDisconnect(ac);
 }
 
+/* Internal helper function to detect socket status the first time a read or
+ * write event fires. When connecting was not succesful, the connect callback
+ * is called with a REDIS_ERR status and the context is free'd. */
+static int __redisAsyncHandleConnect(redisAsyncContext *ac) {
+    redisContext *c = &(ac->c);
+
+    if (redisCheckSocketError(c,c->fd) == REDIS_ERR) {
+        /* Try again later when connect(2) is still in progress. */
+        if (errno == EINPROGRESS)
+            return REDIS_OK;
+
+        if (ac->onConnect) ac->onConnect(ac,REDIS_ERR);
+        __redisAsyncDisconnect(ac);
+        return REDIS_ERR;
+    }
+
+    /* Mark context as connected. */
+    c->flags |= REDIS_CONNECTED;
+    if (ac->onConnect) ac->onConnect(ac,REDIS_OK);
+    return REDIS_OK;
+}
+
 /* This function should be called when the socket is readable.
  * It processes all replies that can be read and executes their callbacks.
  */
 void redisAsyncHandleRead(redisAsyncContext *ac) {
     redisContext *c = &(ac->c);
 
+    if (!(c->flags & REDIS_CONNECTED)) {
+        /* Abort connect was not successful. */
+        if (__redisAsyncHandleConnect(ac) != REDIS_OK)
+            return;
+        /* Try again later when the context is still not connected. */
+        if (!(c->flags & REDIS_CONNECTED))
+            return;
+    }
+
     if (redisBufferRead(c) == REDIS_ERR) {
         __redisAsyncDisconnect(ac);
     } else {
@@ -438,6 +471,15 @@ void redisAsyncHandleWrite(redisAsyncContext *ac) {
     redisContext *c = &(ac->c);
     int done = 0;
 
+    if (!(c->flags & REDIS_CONNECTED)) {
+        /* Abort connect was not successful. */
+        if (__redisAsyncHandleConnect(ac) != REDIS_OK)
+            return;
+        /* Try again later when the context is still not connected. */
+        if (!(c->flags & REDIS_CONNECTED))
+            return;
+    }
+
     if (redisBufferWrite(c,&done) == REDIS_ERR) {
         __redisAsyncDisconnect(ac);
     } else {
@@ -449,12 +491,6 @@ void redisAsyncHandleWrite(redisAsyncContext *ac) {
 
         /* Always schedule reads after writes */
         _EL_ADD_READ(ac);
-
-        /* Fire onConnect when this is the first write event. */
-        if (!(c->flags & REDIS_CONNECTED)) {
-            c->flags |= REDIS_CONNECTED;
-            if (ac->onConnect) ac->onConnect(ac);
-        }
     }
 }
 

async.h

@@ -55,7 +55,7 @@ typedef struct redisCallbackList {
 
 /* Connection callback prototypes */
 typedef void (redisDisconnectCallback)(const struct redisAsyncContext*, int status);
-typedef void (redisConnectCallback)(const struct redisAsyncContext*);
+typedef void (redisConnectCallback)(const struct redisAsyncContext*, int status);
 
 /* Context for an async connection to Redis */
 typedef struct redisAsyncContext {