From b1f1c108783a7d9fb3b4e9eaa80053f0d52425bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eric=20Espi=C3=A9?= <eric.espie@combodo.com>
Date: Mon, 2 Oct 2017 07:30:41 +0000
Subject: [PATCH] APC emulation using files when APC or APCu is not installed.

SVN:trunk[4954]
---
 core/apc-compat.php    |   6 ++
 core/apc-emulation.php | 221 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 227 insertions(+)
 create mode 100644 core/apc-emulation.php

diff --git a/core/apc-compat.php b/core/apc-compat.php
index 00f8ff991..0566d04e0 100644
--- a/core/apc-compat.php
+++ b/core/apc-compat.php
@@ -89,4 +89,10 @@ function apc_cache_info_compat()
 		$aCacheUserData = @apc_cache_info('user');
 	}
 	return $aCacheUserData;
+}
+
+// Cache emulation
+if (!function_exists('apc_store'))
+{
+	require_once(APPROOT.'core/apc-emulation.php');
 }
\ No newline at end of file
diff --git a/core/apc-emulation.php b/core/apc-emulation.php
new file mode 100644
index 000000000..409b16ea4
--- /dev/null
+++ b/core/apc-emulation.php
@@ -0,0 +1,221 @@
+<?php
+// Copyright (c) 2010-2017 Combodo SARL
+//
+//   This file is part of iTop.
+//
+//   iTop is free software; you can redistribute it and/or modify
+//   it under the terms of the GNU Affero General Public License as published by
+//   the Free Software Foundation, either version 3 of the License, or
+//   (at your option) any later version.
+//
+//   iTop is distributed in the hope that it will be useful,
+//   but WITHOUT ANY WARRANTY; without even the implied warranty of
+//   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//   GNU Affero General Public License for more details.
+//
+//   You should have received a copy of the GNU Affero General Public License
+//   along with iTop. If not, see <http://www.gnu.org/licenses/>
+//
+
+/**
+ * Date: 27/09/2017
+ */
+
+
+/**
+ * @param array|string $key
+ * @param $var
+ * @param int $ttl
+ * @return array|bool
+ */
+function apc_store($key, $var = NULL, $ttl = 0)
+{
+	if (is_array($key))
+	{
+		$aResult = array();
+		foreach($key as $sKey => $value)
+		{
+			$aResult[] = apc_emul_store_unit($sKey, $value, $ttl);
+		}
+		return $aResult;
+	}
+	return apc_emul_store_unit($key, $var, $ttl);
+}
+
+/**
+ * @param string $sKey
+ * @param $value
+ * @param int $iTTL time to live
+ * @return bool
+ */
+function apc_emul_store_unit($sKey, $value, $iTTL)
+{
+	if ($iTTL > 0)
+	{
+		// hint for ttl management
+		$sKey = '-'.$sKey;
+	}
+
+	$sFilename = apc_emul_get_cache_filename($sKey);
+	// try to create the folder
+	$sDirname = dirname($sFilename);
+	if (!file_exists($sDirname))
+	{
+		if (!@mkdir($sDirname, 0755, true))
+		{
+			return false;
+		}
+	}
+	$bRes = !(@file_put_contents($sFilename, serialize($value), LOCK_EX) === false);
+	apc_emul_manage_ttl();
+	return $bRes;
+}
+
+/**
+ * @param $key string|array
+ * @return mixed
+ */
+function apc_fetch($key)
+{
+	if (is_array($key))
+	{
+		$aResult = array();
+		foreach($key as $sKey)
+		{
+			$aResult[$sKey] = apc_emul_fetch_unit($sKey);
+		}
+		return $aResult;
+	}
+	return apc_emul_fetch_unit($key);
+}
+
+function apc_emul_fetch_unit($sKey)
+{
+	// Try the 'TTLed' version
+	$sValue = apc_emul_readcache_locked(apc_emul_get_cache_filename('-'.$sKey));
+	if ($sValue === false)
+	{
+		$sValue = apc_emul_readcache_locked(apc_emul_get_cache_filename($sKey));
+		if ($sValue === false)
+		{
+			return false;
+		}
+	}
+	$oRes = @unserialize($sValue);
+	return $oRes;
+}
+
+function apc_emul_readcache_locked($sFilename)
+{
+	$file = @fopen($sFilename, 'r');
+	if ($file === false)
+	{
+		return false;
+	}
+	flock($file, LOCK_SH);
+	$sContent = @fread($file, @filesize($sFilename));
+	flock($file, LOCK_UN);
+	fclose($file);
+	return $sContent;
+}
+
+/**
+ * @param string $cache_type
+ * @return bool
+ */
+function apc_clear_cache($cache_type = '')
+{
+	$sRootCacheDir = apc_emul_get_cache_filename('');
+	apc_emul_delete_entry($sRootCacheDir);
+	return true;
+}
+
+function apc_emul_delete_entry($sCache)
+{
+	if (is_dir($sCache))
+	{
+		$aFiles = array_diff(scandir($sCache), array('.', '..'));
+		foreach($aFiles as $sFile)
+		{
+			$sSubFile = $sCache.'/'.$sFile;
+			if (!apc_emul_delete_entry($sSubFile))
+			{
+				return false;
+			}
+		}
+		if (!@rmdir($sCache))
+		{
+			return false;
+		}
+	}
+	else
+	{
+		if (!@unlink($sCache))
+		{
+			return false;
+		}
+	}
+	return true;
+}
+
+/**
+ * @param $key
+ * @return bool|string[]
+ */
+function apc_delete($key)
+{
+	return apc_emul_delete_entry(apc_emul_get_cache_filename($key));
+}
+
+
+function apc_emul_get_cache_filename($sKey)
+{
+	$sPath = str_replace(array(' ', '/', '\\', '.'), '-', $sKey);
+	return utils::GetCachePath().'apc-emul/'.$sPath;
+}
+
+
+function apc_emul_manage_ttl()
+{
+	// Check only once per request
+	static $bAlreadyChecked = false;
+	if ($bAlreadyChecked)
+	{
+		return;
+	}
+	$sRootCacheDir = apc_emul_get_cache_filename('');
+	apc_emul_manage_ttl_dir($sRootCacheDir);
+	$bAlreadyChecked = true;
+}
+
+function apc_emul_manage_ttl_dir($sCheck)
+{
+	$iTTL = MetaModel::GetConfig()->Get('apc_cache.query_ttl');
+	// Garbage collection
+	$aFiles = array_diff(@scandir($sCheck), array('.', '..'));
+	foreach($aFiles as $sFile)
+	{
+		$sSubFile = $sCheck.'/'.$sFile;
+		if (is_dir($sSubFile))
+		{
+			apc_emul_manage_ttl_dir($sSubFile);
+		}
+		else
+		{
+			apc_emul_check_ttl_file($sSubFile, $iTTL);
+		}
+	}
+}
+
+function apc_emul_check_ttl_file($sFilename, $iTTL)
+{
+	$iCurTime = time();
+	if (strpos(basename($sFilename), '-') === 0)
+	{
+		$iLimitTime = @fileatime($sFilename) + $iTTL + rand(-$iTTL / 10, $iTTL / 10);
+		if ($iLimitTime < $iCurTime)
+		{
+			@unlink($sFilename);
+		}
+	}
+}