Search sub topics, don't iterate (where possible).

src/subs.c

@@ -387,38 +387,55 @@ static int sub__remove_recurse(struct mosquitto_db *db, struct mosquitto *contex
 static int sub__search(struct mosquitto_db *db, struct mosquitto__subhier *subhier, struct sub__token *tokens, const char *source_id, const char *topic, int qos, int retain, struct mosquitto_msg_store *stored, bool set_retain)
 {
 	/* FIXME - need to take into account source_id if the client is a bridge */
-	struct mosquitto__subhier *branch, *branch_tmp;
-	bool sr;
+	struct mosquitto__subhier *branch;
 	int rc;
 	bool have_subscribers = false;
 
-	HASH_ITER(hh, subhier->children, branch, branch_tmp){
-		sr = set_retain;
-
-		if(tokens && tokens->topic
-					&& (!strcmp(branch->topic, tokens->topic)
-					|| !strcmp(branch->topic, "+"))){
-			/* The topic matches this subscription.
-			 * Doesn't include # wildcards */
-			if(!strcmp(branch->topic, "+")){
-				/* Don't set a retained message where + is in the hierarchy. */
-				sr = false;
-			}
-			rc = sub__search(db, branch, tokens->next, source_id, topic, qos, retain, stored, sr);
+	if(tokens){
+		/* Check for literal match */
+		HASH_FIND(hh, subhier->children, tokens->topic, tokens->topic_len, branch);
+
+		if(branch){
+			rc = sub__search(db, branch, tokens->next, source_id, topic, qos, retain, stored, set_retain);
+			if(rc == MOSQ_ERR_SUCCESS){
+				have_subscribers = true;
+			}else if(rc != MOSQ_ERR_NO_SUBSCRIBERS){
+				return rc;
+			}
+			if(!tokens->next){
+				rc = subs__process(db, branch, source_id, topic, qos, retain, stored, set_retain);
+				if(rc == MOSQ_ERR_SUCCESS){
+					have_subscribers = true;
+				}else if(rc != MOSQ_ERR_NO_SUBSCRIBERS){
+					return rc;
+				}
+			}
+		}
+
+		/* Check for + match */
+		HASH_FIND(hh, subhier->children, "+", 1, branch);
+
+		if(branch){
+			rc = sub__search(db, branch, tokens->next, source_id, topic, qos, retain, stored, false);
 			if(rc == MOSQ_ERR_SUCCESS){
 				have_subscribers = true;
 			}else if(rc != MOSQ_ERR_NO_SUBSCRIBERS){
 				return rc;
 			}
 			if(!tokens->next){
-				rc = subs__process(db, branch, source_id, topic, qos, retain, stored, sr);
+				rc = subs__process(db, branch, source_id, topic, qos, retain, stored, false);
 				if(rc == MOSQ_ERR_SUCCESS){
 					have_subscribers = true;
 				}else if(rc != MOSQ_ERR_NO_SUBSCRIBERS){
 					return rc;
 				}
 			}
-		}else if(!strcmp(branch->topic, "#") && !branch->children){
+		}
+	}
+
+	/* Check for # match */
+	HASH_FIND(hh, subhier->children, "#", 1, branch);
+	if(branch && !branch->children){
 		/* The topic matches due to a # wildcard - process the
 		 * subscriptions but *don't* return. Although this branch has ended
 		 * there may still be other subscriptions to deal with.
@@ -430,7 +447,7 @@ static int sub__search(struct mosquitto_db *db, struct mosquitto__subhier *subhi
 			return rc;
 		}
 	}
-	}
+
 	if(have_subscribers){
 		return MOSQ_ERR_SUCCESS;
 	}else{
@@ -739,11 +756,8 @@ static int retain__search(struct mosquitto_db *db, struct mosquitto__subhier *su
 	struct mosquitto__subhier *branch, *branch_tmp;
 	int flag = 0;
 
-	HASH_ITER(hh, subhier->children, branch, branch_tmp){
-		/* Subscriptions with wildcards in aren't really valid topics to publish to
-		 * so they can't have retained messages.
-		 */
 	if(!strcmp(tokens->topic, "#") && !tokens->next){
+		HASH_ITER(hh, subhier->children, branch, branch_tmp){
 			/* Set flag to indicate that we should check for retained messages
 			 * on "foo" when we are subscribing to e.g. "foo/#" and then exit
 			 * this function and return to an earlier retain__search().
@@ -755,12 +769,13 @@ static int retain__search(struct mosquitto_db *db, struct mosquitto__subhier *su
 			if(branch->children){
 				retain__search(db, branch, tokens, context, sub, sub_qos, subscription_identifier, now, level+1);
 			}
-		}else if(strcmp(branch->topic, "+")
-					&& (!strcmp(branch->topic, tokens->topic)
-					|| !strcmp(tokens->topic, "+"))){
+		}
+	}else{
+		if(!strcmp(tokens->topic, "+")){
+			HASH_ITER(hh, subhier->children, branch, branch_tmp){
 				if(tokens->next){
 					if(retain__search(db, branch, tokens->next, context, sub, sub_qos, subscription_identifier, now, level+1) == -1
-						|| (!branch_tmp && tokens->next && !strcmp(tokens->next->topic, "#") && level>0)){
+							|| (tokens->next && !strcmp(tokens->next->topic, "#") && level>0)){
 
 						if(branch->retained){
 							retain__process(db, branch, context, sub_qos, subscription_identifier, now);
@@ -772,6 +787,24 @@ static int retain__search(struct mosquitto_db *db, struct mosquitto__subhier *su
 					}
 				}
 			}
+		}else{
+			HASH_FIND(hh, subhier->children, tokens->topic, tokens->topic_len, branch);
+			if(branch){
+				if(tokens->next){
+					if(retain__search(db, branch, tokens->next, context, sub, sub_qos, subscription_identifier, now, level+1) == -1
+							|| (tokens->next && !strcmp(tokens->next->topic, "#") && level>0)){
+
+						if(branch->retained){
+							retain__process(db, branch, context, sub_qos, subscription_identifier, now);
+						}
+					}
+				}else{
+					if(branch->retained){
+						retain__process(db, branch, context, sub_qos, subscription_identifier, now);
+					}
+				}
+			}
+		}
 	}
 	return flag;
 }