Avoid hanging getStats() when binary protocol and non-blocking are both enabled

Fixes #348.

Author: sodabrew

Diff for: package.xml

@@ -168,6 +168,7 @@ Fixes
     <file role='test' name='session_lazy_warning.phpt'/>
     <file role='test' name='session_regenerate.phpt'/>
     <file role='test' name='stats.phpt'/>
+    <file role='test' name='stats_hang.phpt'/>
     <file role='test' name='default_behavior.phpt'/>
     <file role='test' name='reset_keyprefix.phpt'/>
     <file role='test' name='session_lock-php71.phpt'/>

Diff for: php_memcached.c

@@ -2757,6 +2757,7 @@ PHP_METHOD(Memcached, getStats)
 	memcached_return status;
 	char *args = NULL;
 	zend_string *args_string = NULL;
+	uint64_t orig_no_block, orig_protocol;
 	MEMC_METHOD_INIT_VARS;
 
 	/* "|S!" */
@@ -2770,8 +2771,19 @@ PHP_METHOD(Memcached, getStats)
 	if (args_string)
 		args = ZSTR_VAL(args_string);
 
+	/* stats hangs in nonblocking mode, turn off during the call. Only change the
+	 * value if needed, because libmemcached reconnects for this behavior_set. */
+	orig_no_block = memcached_behavior_get(intern->memc, MEMCACHED_BEHAVIOR_NO_BLOCK);
+	orig_protocol = memcached_behavior_get(intern->memc, MEMCACHED_BEHAVIOR_BINARY_PROTOCOL);
+	if (orig_no_block && orig_protocol)
+		memcached_behavior_set(intern->memc, MEMCACHED_BEHAVIOR_NO_BLOCK, 0);
+
 	array_init(return_value);
 	status = memcached_stat_execute(intern->memc, args, s_stat_execute_cb, return_value);
+
+	if (orig_no_block && orig_protocol)
+		memcached_behavior_set(intern->memc, MEMCACHED_BEHAVIOR_NO_BLOCK, orig_no_block);
+
 	if (s_memc_status_handle_result_code(intern, status) == FAILURE) {
 		zval_ptr_dtor(return_value);
 		RETURN_FALSE;

Diff for: tests/stats_hang.phpt

@@ -0,0 +1,89 @@
+--TEST--
+Check stats does not hang on non-blocking binary protocol
+--SKIPIF--
+<?php include "skipif.inc";?>
+--FILE--
+<?php
+include dirname (__FILE__) . '/config.inc';
+$m = memc_get_instance ();
+
+$key = MEMC_SERVER_HOST . ':' . MEMC_SERVER_PORT;
+
+// Both options set means we have to reconnect to get stats
+$m->setOption(Memcached::OPT_NO_BLOCK, true);
+$m->setOption(Memcached::OPT_BINARY_PROTOCOL, true);
+
+$stats = $m->getStats();
+$conns1 = $stats[$key]['total_connections'];
+
+$stats = $m->getStats();
+$conns2 = $stats[$key]['total_connections'];
+
+var_dump($conns1 == $conns2);
+var_dump($m->getOption(Memcached::OPT_NO_BLOCK));
+var_dump($m->getOption(Memcached::OPT_BINARY_PROTOCOL));
+echo "OK" . PHP_EOL;
+
+// If either or both options are false no need to reconnect
+$m->setOption(Memcached::OPT_NO_BLOCK, false);
+$m->setOption(Memcached::OPT_BINARY_PROTOCOL, true);
+
+$stats = $m->getStats();
+$conns1 = $stats[$key]['total_connections'];
+
+$stats = $m->getStats();
+$conns2 = $stats[$key]['total_connections'];
+
+var_dump($conns1 == $conns2);
+var_dump($m->getOption(Memcached::OPT_NO_BLOCK));
+var_dump($m->getOption(Memcached::OPT_BINARY_PROTOCOL));
+echo "OK" . PHP_EOL;
+
+// If either or both options are false no need to reconnect
+$m->setOption(Memcached::OPT_NO_BLOCK, true);
+$m->setOption(Memcached::OPT_BINARY_PROTOCOL, false);
+
+$stats = $m->getStats();
+$conns1 = $stats[$key]['total_connections'];
+
+$stats = $m->getStats();
+$conns2 = $stats[$key]['total_connections'];
+
+var_dump($conns1 == $conns2);
+var_dump($m->getOption(Memcached::OPT_NO_BLOCK));
+var_dump($m->getOption(Memcached::OPT_BINARY_PROTOCOL));
+echo "OK" . PHP_EOL;
+
+// If either or both options are false no need to reconnect
+$m->setOption(Memcached::OPT_NO_BLOCK, false);
+$m->setOption(Memcached::OPT_BINARY_PROTOCOL, false);
+
+$stats = $m->getStats();
+$conns1 = $stats[$key]['total_connections'];
+
+$stats = $m->getStats();
+$conns2 = $stats[$key]['total_connections'];
+
+var_dump($conns1 == $conns2);
+var_dump($m->getOption(Memcached::OPT_NO_BLOCK));
+var_dump($m->getOption(Memcached::OPT_BINARY_PROTOCOL));
+echo "OK" . PHP_EOL;
+
+?>
+--EXPECT--
+bool(false)
+int(1)
+int(1)
+OK
+bool(true)
+int(0)
+int(1)
+OK
+bool(true)
+int(1)
+int(0)
+OK
+bool(true)
+int(0)
+int(0)
+OK