Debugger: removes output buffer for Bar, Bluescreen and production error. It decides whether clean or flush output buffers.

- ob_start() without callback & chunk-size is usually used to capture output to string -> clean it
- ob_start() with callback and/or chunk-size is usually used to preprocess (gzip) or branch off (bluescreen) output -> flush it

zlib.output_compression and ob_gzhandler are unremovable in PHP >= 5.4 only after first chunk was sent

Author: dg

src/Tracy/Debugger.php

@@ -38,6 +38,9 @@ class Debugger
 	/** @var string reserved memory; also prevents double rendering */
 	private static $reserved;
 
+	/** @var int initial output buffer level */
+	private static $obLevel;
+
 	/********************* errors and exceptions reporting ****************d*g**/
 
 	/** @var bool|int determines whether any error will cause immediate death; if integer that it's matched against error severity */
@@ -129,6 +132,7 @@ public static function enable($mode = NULL, $logDirectory = NULL, $email = NULL)
 	{
 		self::$reserved = str_repeat('t', 3e5);
 		self::$time = isset($_SERVER['REQUEST_TIME_FLOAT']) ? $_SERVER['REQUEST_TIME_FLOAT'] : microtime(TRUE);
+		self::$obLevel = ob_get_level();
 		error_reporting(E_ALL);
 
 		if ($mode !== NULL || self::$productionMode === NULL) {
@@ -203,6 +207,7 @@ public static function shutdownHandler()
 
 		} elseif (self::$showBar && !connection_aborted() && !self::$productionMode && self::isHtmlMode()) {
 			self::$reserved = NULL;
+			self::removeOutputBuffers();
 			self::getBar()->render();
 		}
 	}
@@ -231,6 +236,7 @@ public static function exceptionHandler($exception, $exit = TRUE)
 		}
 
 		Helpers::improveException($exception);
+		self::removeOutputBuffers();
 
 		if (self::$productionMode) {
 			try {
@@ -339,10 +345,6 @@ public static function errorHandler($severity, $message, $file, $line, $context)
 			$e = new ErrorException($message, 0, $severity, $file, $line);
 			$e->context = $context;
 			$e->skippable = TRUE;
-			do {
-				$level = ob_get_level();
-				@ob_end_clean(); // @ may not exist or is not removable
-			} while ($level !== ob_get_level());
 			self::exceptionHandler($e);
 		}
 
@@ -375,6 +377,21 @@ private static function isHtmlMode()
 	}
 
 
+	private static function removeOutputBuffers()
+	{
+		while (ob_get_level() > self::$obLevel) {
+			$status = ob_get_status();
+			if (in_array($status['name'], ['ob_gzhandler', 'zlib output compression'])) {
+				break;
+			}
+			$fnc = $status['chunk_size'] ? 'ob_end_flush' : 'ob_end_clean';
+			if (!@$fnc()) { // @ may be not removable
+				break;
+			}
+		}
+	}
+
+
 	/********************* services ****************d*g**/
 
 

tests/Tracy/Debugger.E_COMPILE_ERROR.console.phpt

@@ -17,6 +17,7 @@ require __DIR__ . '/../bootstrap.php';
 Debugger::$productionMode = FALSE;
 header('Content-Type: text/plain');
 
+ob_start();
 Debugger::enable();
 
 $onFatalErrorCalled = FALSE;
@@ -47,7 +48,6 @@ Unable to log error: Directory is not specified.
 Debugger::$onFatalError[] = function () use (& $onFatalErrorCalled) {
 	$onFatalErrorCalled = TRUE;
 };
-ob_start();
 
 
 function first($arg1, $arg2)

tests/Tracy/Debugger.E_ERROR.console.phpt

@@ -17,6 +17,7 @@ require __DIR__ . '/../bootstrap.php';
 Debugger::$productionMode = FALSE;
 header('Content-Type: text/plain');
 
+ob_start();
 Debugger::enable();
 
 $onFatalErrorCalled = FALSE;
@@ -55,7 +56,6 @@ Unable to log error: Directory is not specified.
 Debugger::$onFatalError[] = function () use (& $onFatalErrorCalled) {
 	$onFatalErrorCalled = TRUE;
 };
-ob_start();
 
 
 function first($arg1, $arg2)

tests/Tracy/Debugger.E_ERROR.html.phpt

@@ -21,6 +21,7 @@ if (PHP_SAPI === 'cli') {
 Debugger::$productionMode = FALSE;
 header('Content-Type: text/html');
 
+ob_start();
 Debugger::enable();
 
 
@@ -38,7 +39,7 @@ register_shutdown_function(function () use (& $onFatalErrorCalled) {
 Debugger::$onFatalError[] = function () use (& $onFatalErrorCalled) {
 	$onFatalErrorCalled = TRUE;
 };
-ob_start();
+
 
 
 function first($arg1, $arg2)

tests/Tracy/Debugger.barDump().phpt

@@ -19,14 +19,14 @@ if (PHP_SAPI === 'cli') {
 Debugger::$productionMode = FALSE;
 header('Content-Type: text/html');
 
+ob_start();
 Debugger::enable();
 
 register_shutdown_function(function () {
 	preg_match('#debug.innerHTML = (".*");#', ob_get_clean(), $m);
 	Assert::matchFile(__DIR__ . '/Debugger.barDump().expect', json_decode($m[1]));
 	echo 'OK!'; // prevents PHP bug #62725
 });
-ob_start();
 
 
 $arr = [10, 20.2, TRUE, FALSE, NULL, 'hello', ['key1' => 'val1', 'key2' => TRUE], (object) ['key1' => 'val1', 'key2' => TRUE]];

tests/Tracy/Debugger.barDump().showLocation.phpt

@@ -20,6 +20,7 @@ Debugger::$productionMode = FALSE;
 Debugger::$showLocation = TRUE;
 header('Content-Type: text/html');
 
+ob_start();
 Debugger::enable();
 
 register_shutdown_function(function () {
@@ -38,7 +39,6 @@ EOD
 , json_decode($m[1]));
 	echo 'OK!'; // prevents PHP bug #62725
 });
-ob_start();
 
 
 Debugger::barDump('value');

tests/Tracy/Debugger.logging.error.phpt

@@ -21,6 +21,7 @@ Debugger::$logDirectory = TEMP_DIR;
 
 Debugger::getLogger()->mailer = function () {};
 
+ob_start();
 Debugger::enable(Debugger::PRODUCTION, NULL, 'admin@example.com');
 
 
@@ -29,7 +30,6 @@ register_shutdown_function(function () {
 	Assert::true(is_file(Debugger::$logDirectory . '/email-sent'));
 	echo 'OK!'; // prevents PHP bug #62725
 });
-ob_start();
 
 
 missing_function();

tests/Tracy/Debugger.warnings.console.phpt

@@ -14,6 +14,7 @@ require __DIR__ . '/../bootstrap.php';
 Debugger::$productionMode = FALSE;
 header('Content-Type: text/plain');
 
+ob_start();
 Debugger::enable();
 
 
@@ -38,7 +39,6 @@ function third($arg1)
 	require 'E_COMPILE_WARNING.php'; // E_COMPILE_WARNING
 }
 
-ob_start();
 first(10, 'any string');
 Assert::match("
 %a%: mktime(): You should be using the time() function instead in %a% on line %d%

tests/Tracy/Debugger.warnings.html.phpt

@@ -19,6 +19,7 @@ if (PHP_SAPI === 'cli') {
 Debugger::$productionMode = FALSE;
 header('Content-Type: text/html');
 
+ob_start();
 Debugger::enable();
 
 register_shutdown_function(function () {
@@ -47,7 +48,6 @@ Warning: Unsupported declare \'foo\' in %a% on line %d%%A%', $output);
 </div>%A%', json_decode($m[1]));
 	echo 'OK!'; // prevents PHP bug #62725
 });
-ob_start();
 
 
 function first($arg1, $arg2)