ext/ldap: Allow default host from ldap.conf to work.

This fixes an regression introduced in
e7af0fe. Previously, calling
ldap_connect() with no parameters would pass NULL to ldap_init(),
which causes it to use the default host specified in
/etc/ldap/ldap.conf (on Ubuntu).

When the code changed to use ldap_initialize(), it initialized a uri,
even if there were no parameters passed to ldap_connect(). Because of
this, there's no way to pass a NULL into ldap_initialize(), making it
impossible to use the default uri from ldap.conf.

This commit bypasses the uri creation when there is no host argument,
passing on a NULL to ldap_initialize() which restores the old PHP 5.5
behavior.

Author: caldwell

ext/ldap/ldap.c

@@ -366,7 +366,7 @@ PHP_FUNCTION(ldap_connect)
 	{
 		int rc = LDAP_SUCCESS;
 		char	*url = host;
-		if (!ldap_is_ldap_url(url)) {
+		if (url && !ldap_is_ldap_url(url)) {
 			int	urllen = hostlen + sizeof( "ldap://:65535" );
 
 			if (port <= 0 || port > 65535) {
@@ -376,7 +376,7 @@ PHP_FUNCTION(ldap_connect)
 			}
 
 			url = emalloc(urllen);
-			snprintf( url, urllen, "ldap://%s:%ld", host ? host : "", port );
+			snprintf( url, urllen, "ldap://%s:%ld", host, port );
 		}
 
 #ifdef LDAP_API_FEATURE_X_OPENLDAP