API CHANGE: Added increase_memory_limit_to() for increasing but not decreasing memory limit.

git-svn-id: svn://svn.silverstripe.com/silverstripe/open/modules/sapphire/branches/2.3@78632 467b73ca-7a2a-4603-9d3b-597d59a354a9

core/Core.php

@@ -125,26 +125,8 @@ define('PR_LOW',10);
 /**
  * Ensure we have enough memory
  */
-$memString = ini_get("memory_limit");
-switch(strtolower(substr($memString, -1))) {
-case "k":
-	$memory = round(substr($memString, 0, -1)*1024);
-	break;
-case "m":
-	$memory = round(substr($memString, 0, -1)*1024*1024);
-	break;
-case "g":
-	$memory = round(substr($memString, 0, -1)*1024*1024*1024);
-	break;
-default:
-	$memory = round($memString);
-}
 
-// Check we have at least 64M
+increase_memory_limit_to('64M');
-if ($memory < (64 * 1024 * 1024)) {
-	// Increase memory limit
-	ini_set('memory_limit', '64M');
-}
 
 ///////////////////////////////////////////////////////////////////////////////
 // INCLUDES
@@ -298,4 +280,28 @@ function _t($entity, $string = "", $priority = 40, $context = "") {
 	return i18n::_t($entity, $string, $priority, $context);
 }
 
+/**
+ * Increase the memory limit to the given level if it's currently too low.
+ * @param A memory limit string, such as "64M"
+ */
+function increase_memory_limit_to($memoryLimit) {
+	// Increase the memory limit if it's too low
+	if(translate_memstring($memoryLimit) >  translate_memstring(ini_get('memory_limit'))) {
+		ini_set('memory_limit', $memoryLimit);
+	}
+}
+
+/**
+ * Turn a memory string, such as 512M into an actual number of bytes.
+ * @param A memory limit string, such as "64M"
+ */
+function translate_memstring($memString) {
+	switch(strtolower(substr($memString, -1))) {
+		case "k": return round(substr($memString, 0, -1)*1024);
+		case "m": return round(substr($memString, 0, -1)*1024*1024);
+		case "g": return round(substr($memString, 0, -1)*1024*1024*1024);
+		default: return round($memString);
+	}
+}
+
 ?>

dev/BulkLoader.php

@@ -130,7 +130,9 @@ abstract class BulkLoader extends ViewableData {
 	 */
 	public function load($filepath, $memory_limit='512M') {
 		ini_set('max_execution_time', 3600);
-		ini_set('memory_limit', $memory_limit);
+		
+		increase_memory_limit_to($memory_limit);
+		
 		return $this->processAll($filepath);
 	}
 	

tests/MemoryLimitTest.php

@@ -0,0 +1,38 @@
+<?php
+
+class MemoryLimitTest extends SapphireTest {
+	
+	function testIncreaseMemoryLimitTo() {
+		ini_set('memory_limit', '64M');
+		
+		// It can go up
+		increase_memory_limit_to('128M');
+		$this->assertEquals('128M', ini_get('memory_limit'));
+
+		// But not down
+		increase_memory_limit_to('64M');
+		$this->assertEquals('128M', ini_get('memory_limit'));
+		
+		// Test the different kinds of syntaxes
+		increase_memory_limit_to(1024*1024*200);
+		$this->assertEquals(1024*1024*200, ini_get('memory_limit'));
+
+		increase_memory_limit_to('409600K');
+		$this->assertEquals('409600K', ini_get('memory_limit'));
+
+		increase_memory_limit_to('1G');
+		$this->assertEquals('1G', ini_get('memory_limit'));
+	}
+
+
+	///////////////////
+	
+	private $origLimit;
+	
+	function setUp() {
+		$this->origLimit = ini_get('memory_limit');
+	}
+	function tearDown() {
+		ini_set('memory_limit', $this->origLimit);
+	}
+}