Proyectos de Subversion Moodle

<?php

/*

pCache - speed up the rendering by caching up the pictures

Version     : 2.1.4

Made by     : Jean-Damien POGOLOTTI

Last Update : 19/01/2014

This file can be distributed under the license you can find at :

http://www.pchart.net/license

You can find the whole class documentation on the pChart web site.

*/

/* pData class definition */

class pCache

{

	var $CacheFolder;

	var $CacheIndex;

	var $CacheDB;

	/* Class creator */

	function __construct(array $Settings = [])

	{

		#if (!is_dir("cache")){

		#	mkdir("cache", 0775);

		#}

		$this->CacheFolder = isset($Settings["CacheFolder"]) ? $Settings["CacheFolder"] : "cache";

		$this->CacheIndex = isset($Settings["CacheIndex"]) ? $Settings["CacheIndex"] : "index.db";

		$this->CacheIndex = $this->CacheFolder . "/" . $this->CacheIndex;

		$this->CacheDB = isset($Settings["CacheDB"]) ? $Settings["CacheDB"] : "cache.db";

		$this->CacheDB = $this->CacheFolder . "/" . $this->CacheDB;

		if (!file_exists($this->CacheIndex)) {

			touch($this->CacheIndex);

		}

		if (!file_exists($this->CacheDB)) {

			touch($this->CacheDB);

		}

	}

	/* Flush the cache contents */

	function flush()

	{

		file_put_contents($this->CacheIndex, "");

		file_put_contents($this->CacheDB, "");

	}

	/* Return the MD5 of the data array to clearly identify the chart */

	function getHash($Data, $Marker = "")

	{

		return (md5($Marker . serialize($Data->Data)));

	}

	/* Write the generated picture to the cache */

	function writeToCache($ID, $pChartObject)

	{

		/* Compute the paths */

		$TemporaryFile = $this->CacheFolder . "/tmp_" . rand(0, 1000) . ".png";

		/* Flush the picture to a temporary file */

		imagepng($pChartObject->Picture, $TemporaryFile);

		/* Retrieve the files size */

		$PictureSize = filesize($TemporaryFile);

		$DBSize = filesize($this->CacheDB);

		/* Save the index */

		$Handle = fopen($this->CacheIndex, "a");

		fwrite($Handle, $ID . "," . $DBSize . "," . $PictureSize . "," . time() . ",0      \r\n");

		fclose($Handle);

		/* Get the picture raw contents */

		$Handle = fopen($TemporaryFile, "r");

		$Raw = fread($Handle, $PictureSize);

		fclose($Handle);

		/* Save the picture in the solid database file */

		$Handle = fopen($this->CacheDB, "a");

		fwrite($Handle, $Raw);

		fclose($Handle);

		/* Remove temporary file */

		unlink($TemporaryFile);

	}

	/* Remove object older than the specified TS */

	function removeOlderThan($Expiry)

	{

		$this->dbRemoval(["Expiry" => $Expiry]);

	}

	/* Remove an object from the cache */

	function remove($ID)

	{

		$this->dbRemoval(["Name" => $ID]);

	}

	/* Remove with specified criterias */

	function dbRemoval($Settings)

	{

		$ID = isset($Settings["Name"]) ? $Settings["Name"] : NULL;

		$Expiry = isset($Settings["Expiry"]) ? $Settings["Expiry"] : -(24 * 60 * 60);

		$TS = time() - $Expiry;

		/* Compute the paths */

		$DatabaseTemp = $this->CacheDB . ".tmp";

		$IndexTemp = $this->CacheIndex . ".tmp";

		/* Single file removal */

		if ($ID != NULL) {

			/* If it's not in the cache DB, go away */

			if (!$this->isInCache($ID, TRUE)) {

				return 0;

			}

		}

		/* Create the temporary files */

		if (!file_exists($DatabaseTemp)) {

			touch($DatabaseTemp);

		}

		if (!file_exists($IndexTemp)) {

			touch($IndexTemp);

		}

		/* Open the file handles */

		$IndexHandle = fopen($this->CacheIndex, "r");

		$IndexTempHandle = fopen($IndexTemp, "w");

		$DBHandle = fopen($this->CacheDB, "r");

		$DBTempHandle = fopen($DatabaseTemp, "w");

		/* Remove the selected ID from the database */

		if ($IndexHandle && $IndexTempHandle && $DBHandle && $DBTempHandle) {

			while (!feof($IndexHandle)) {

				$Entry = fgets($IndexHandle, 4096);

				$Entry = str_replace("\r", "", $Entry);

				$Entry = str_replace("\n", "", $Entry);

				$Settings = explode(",", $Entry);

				if ($Entry != "") {

					$PicID = $Settings[0];

					$DBPos = $Settings[1];

					$PicSize = $Settings[2];

					$GeneratedTS = $Settings[3];

					$Hits = $Settings[4];

					if ($Settings[0] != $ID && $GeneratedTS > $TS) {

						$CurrentPos = ftell($DBTempHandle);

						fwrite($IndexTempHandle, $PicID . "," . $CurrentPos . "," . $PicSize . "," . $GeneratedTS . "," . $Hits . "\r\n");

						fseek($DBHandle, $DBPos);

						$Picture = fread($DBHandle, $PicSize);

						fwrite($DBTempHandle, $Picture);

					}

				}

			}

			/* Close the handles */

			fclose($IndexHandle);

			fclose($IndexTempHandle);

			fclose($DBHandle);

			fclose($DBTempHandle);

		}

		/* Remove the prod files */

		unlink($this->CacheDB);

		unlink($this->CacheIndex);

		/* Swap the temp & prod DB */

		rename($DatabaseTemp, $this->CacheDB);

		rename($IndexTemp, $this->CacheIndex);

	}

	function isInCache($ID, $Verbose = FALSE, $UpdateHitsCount = FALSE)

	{

		/* Search the picture in the index file */

		$Handle = fopen($this->CacheIndex, "r");

		if ($Handle){

			while (!feof($Handle)) {

				$IndexPos = ftell($Handle);

				$Entry = fgets($Handle, 4096);

				if ($Entry != "") {

					$Settings = explode(",", $Entry);

					$PicID = $Settings[0];

					if ($PicID == $ID) {

						fclose($Handle);

						$DBPos = $Settings[1];

						$PicSize = $Settings[2];

						$GeneratedTS = $Settings[3];

						$Hits = intval($Settings[4]);

						if ($UpdateHitsCount) {

							$Hits++;

							if (strlen($Hits) < 7) {

								$Hits = $Hits . str_repeat(" ", 7 - strlen($Hits));

							}

							$Handle = fopen($this->CacheIndex, "r+");

							fseek($Handle, $IndexPos);

							fwrite($Handle, $PicID . "," . $DBPos . "," . $PicSize . "," . $GeneratedTS . "," . $Hits . "\r\n");

							fclose($Handle);

						}

						if ($Verbose) {

							return ["DBPos" => $DBPos,"PicSize" => $PicSize,"GeneratedTS" => $GeneratedTS,"Hits" => $Hits];

						} else {

							return TRUE;

						}

					}

				}

			}

			fclose($Handle);

		}

		/* Picture isn't in the cache */

		return FALSE;

	}

	/* Automatic output method based on the calling interface */

	function autoOutput($ID, $Destination = "output.png")

	{

		if (php_sapi_name() == "cli") {

			$this->saveFromCache($ID, $Destination);

		} else {

			$this->strokeFromCache($ID);

		}

	}

	function strokeFromCache($ID)

	{

		/* Get the raw picture from the cache */

		$Picture = $this->getFromCache($ID);

		/* Do we have a hit? */

		if ($Picture == FALSE) {

			return FALSE;

		}

		header('Content-type: image/png');

		echo $Picture;

	}

	function saveFromCache($ID, $Destination)

	{

		/* Get the raw picture from the cache */

		$Picture = $this->getFromCache($ID);

		/* Do we have a hit? */

		if ($Picture == FALSE) {

			return FALSE;

		}

		/* Flush the picture to a file */

		file_put_contents($Destination, $Picture);

	}

	function getFromCache($ID)

	{

		/* Lookup for the picture in the cache */

		$CacheInfo = $this->isInCache($ID, TRUE, TRUE);

		/* Not in the cache */

		if (!$CacheInfo) {

			# Momchil: fread returns FALSE on failure. Return FALSE here as well and not NULL

			return FALSE;

		}

		/* Get the database extended information */

		$DBPos = $CacheInfo["DBPos"];

		$PicSize = $CacheInfo["PicSize"];

		/* Extract the picture from the solid cache file */

		$Handle = fopen($this->CacheDB, "r");

		fseek($Handle, $DBPos);

		$Picture = fread($Handle, $PicSize);

		fclose($Handle);

		/* Return back the raw picture data */

		return $Picture;

	}

}

?>