From 4bf40df770e2e2e268449852e6e16b02fa9a485d Mon Sep 17 00:00:00 2001
From: "Dylan K. Taylor" <odigiman@gmail.com>
Date: Sun, 31 May 2020 15:10:28 +0100
Subject: [PATCH] tools: added a script to remove garbage from region files

---
 tools/compact-regions.php | 178 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 178 insertions(+)
 create mode 100644 tools/compact-regions.php

diff --git a/tools/compact-regions.php b/tools/compact-regions.php
new file mode 100644
index 000000000..90d3f8ee8
--- /dev/null
+++ b/tools/compact-regions.php
@@ -0,0 +1,178 @@
+<?php
+
+/*
+ *
+ *  ____            _        _   __  __ _                  __  __ ____
+ * |  _ \ ___   ___| | _____| |_|  \/  (_)_ __   ___      |  \/  |  _ \
+ * | |_) / _ \ / __| |/ / _ \ __| |\/| | | '_ \ / _ \_____| |\/| | |_) |
+ * |  __/ (_) | (__|   <  __/ |_| |  | | | | | |  __/_____| |  | |  __/
+ * |_|   \___/ \___|_|\_\___|\__|_|  |_|_|_| |_|\___|     |_|  |_|_|
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * @author PocketMine Team
+ * @link http://www.pocketmine.net/
+ *
+ *
+*/
+
+declare(strict_types=1);
+
+namespace pocketmine\tools\compact_regions;
+
+use pocketmine\world\format\io\exception\CorruptedChunkException;
+use pocketmine\world\format\io\region\CorruptedRegionException;
+use pocketmine\world\format\io\region\RegionLoader;
+use function array_sum;
+use function arsort;
+use function clearstatcache;
+use function count;
+use function defined;
+use function dirname;
+use function file_exists;
+use function filesize;
+use function in_array;
+use function is_dir;
+use function is_file;
+use function number_format;
+use function pathinfo;
+use function rename;
+use function round;
+use function scandir;
+use function unlink;
+use function zlib_decode;
+use function zlib_encode;
+
+require dirname(__DIR__) . '/vendor/autoload.php';
+
+const SUPPORTED_EXTENSIONS = [
+	"mcr",
+	"mca",
+	"mcapm"
+];
+
+/**
+ * @param int[] $files
+ * @phpstan-param array<string, int> $files
+ */
+function find_regions_recursive(string $dir, array &$files) : void{
+	foreach(scandir($dir, SCANDIR_SORT_NONE) as $file){
+		if($file === "." or $file === ".."){
+			continue;
+		}
+		$fullPath = $dir . "/" . $file;
+		if(
+			in_array(pathinfo($fullPath, PATHINFO_EXTENSION), SUPPORTED_EXTENSIONS, true) and
+			is_file($fullPath)
+		){
+			$files[$fullPath] = filesize($fullPath);
+		}elseif(is_dir($fullPath)){
+			find_regions_recursive($fullPath, $files);
+		}
+	}
+}
+
+/**
+ * @param string[] $argv
+ */
+function main(array $argv) : int{
+	if(!isset($argv[1])){
+		echo "Usage: " . PHP_BINARY . " " . __FILE__ . " <path to region folder or file>\n";
+		return 1;
+	}
+
+	$logger = \GlobalLogger::get();
+
+	/** @phpstan-var array<string, int> $files */
+	$files = [];
+	if(is_file($argv[1])){
+		$files[$argv[1]] = filesize($argv[1]);
+	}elseif(is_dir($argv[1])){
+		find_regions_recursive($argv[1], $files);
+	}
+	if(count($files) === 0){
+		echo "No supported files found\n";
+		return 1;
+	}
+
+	arsort($files, SORT_NUMERIC);
+	$currentSize = array_sum($files);
+	$logger->info("Discovered " . count($files) . " files totalling " . number_format($currentSize) . " bytes");
+	$logger->warning("Please DO NOT forcibly kill the compactor, or your files may be damaged.");
+
+	$corruptedFiles = [];
+	$doneCount = 0;
+	$totalCount = count($files);
+	foreach($files as $file => $size){
+		$oldRegion = new RegionLoader($file);
+		try{
+			$oldRegion->open();
+		}catch(CorruptedRegionException $e){
+			$logger->error("Damaged region in file $file (" . $e->getMessage() . "), skipping");
+			$corruptedFiles[] = $file;
+			$doneCount++;
+			continue;
+		}
+
+		$newFile = $file . ".compacted";
+		$newRegion = new RegionLoader($newFile);
+		$newRegion->open();
+
+		$emptyRegion = true;
+		$corruption = false;
+		for($x = 0; $x < 32; $x++){
+			for($z = 0; $z < 32; $z++){
+				try{
+					$data = $oldRegion->readChunk($x, $z);
+				}catch(CorruptedChunkException $e){
+					$logger->error("Damaged chunk $x $z in file $file (" . $e->getMessage() . "), skipping");
+					$corruption = true;
+					continue;
+				}
+				if($data !== null){
+					$emptyRegion = false;
+					$newRegion->writeChunk($x, $z, $data);
+				}
+			}
+		}
+
+		$oldRegion->close();
+		$newRegion->close();
+		if(!$corruption){
+			unlink($file);
+		}else{
+			rename($file, $file . ".bak");
+			$corruptedFiles[] = $file . ".bak";
+		}
+		if(!$emptyRegion){
+			rename($newFile, $file);
+		}else{
+			unlink($newFile);
+		}
+		$doneCount++;
+		$logger->info("Compacted region $file ($doneCount/$totalCount, " . round(($doneCount / $totalCount) * 100, 2) . "%)");
+	}
+
+	clearstatcache();
+	$newSize = 0;
+	foreach($files as $file => $oldSize){
+		$newSize += file_exists($file) ? filesize($file) : 0;
+	}
+	$diff = $currentSize - $newSize;
+	$logger->info("Finished compaction of " . count($files) . " files. Freed " . number_format($diff) . " bytes of space (" . round(($diff / $currentSize) * 100, 2) . "% reduction).");
+	if(count($corruptedFiles) > 0){
+		$logger->error("The following backup files were not removed due to corruption detected:");
+		foreach($corruptedFiles as $file){
+			echo $file . "\n";
+		}
+		return 1;
+	}
+	return 0;
+}
+
+if(!defined('pocketmine\_PHPSTAN_ANALYSIS')){
+	exit(main($argv));
+}