From 82ea1815fd2c24414e207597207d185c3c646c10 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@skiff.com>
Date: Sun, 4 Feb 2024 14:45:32 +0100
Subject: [PATCH 01/11] Refactor cache driver

---
 inc/cache.php               |   2 +-
 inc/driver/cache-driver.php | 266 ++++++++++++++++++++++++++++++++++++
 2 files changed, 267 insertions(+), 1 deletion(-)
 create mode 100644 inc/driver/cache-driver.php

diff --git a/inc/cache.php b/inc/cache.php
index c4053610..ae788bc1 100644
--- a/inc/cache.php
+++ b/inc/cache.php
@@ -25,7 +25,7 @@ class Cache {
 				self::$cache->select($config['cache']['redis'][3]) or die('cache select failure');
 				break;
 			case 'php':
-				self::$cache = array();
+				self::$cache = [];
 				break;
 		}
 	}
diff --git a/inc/driver/cache-driver.php b/inc/driver/cache-driver.php
new file mode 100644
index 00000000..b5279d82
--- /dev/null
+++ b/inc/driver/cache-driver.php
@@ -0,0 +1,266 @@
+<?php
+namespace Vichan\Driver;
+
+use RuntimeException;
+
+defined('TINYBOARD') or exit;
+
+/**
+ * PHP has no nested or private classes support.
+ */
+class CacheDrivers {
+	public static function memcached(string $prefix, string $memcached_server) {
+		$memcached = new Memcached();
+		if (!$memcached->setOption(Memcached::OPT_BINARY_PROTOCOL, true)) {
+			throw new RuntimeException('Unable to set the memcached protocol!');
+		}
+		if (!$memcached->setOption(Memcached::OPT_PREFIX_KEY, $prefix)) {
+			throw new RuntimeException('Unable to set the memcached prefix!');
+		}
+		if (!$memcached->addServers($memcached_server)) {
+			throw new RuntimeException('Unable to add the memcached server!');
+		}
+
+		return new class($memcached) implements CacheDriver {
+			private Memcached $inner;
+
+			public function __construct(Memcached $inner) {
+				$this->inner = $inner;
+			}
+
+			public function get(string $key): mixed {
+				$ret = $this->inner->get($key);
+				// If the returned value is false but the retrival was a success, then the value stored was a boolean false.
+				if ($ret === false && $this->inner->getResultCode() !== Memcached::RES_SUCCESS) {
+					return null;
+				}
+				return $ret;
+			}
+
+			public function set(string $key, mixed $value, mixed $expires = false): void {
+				$this->inner->set($key, $value, (int)$expires);
+			}
+
+			public function delete(string $key): void {
+				$this->inner->delete($key);
+			}
+
+			public function flush(): void {
+				$this->inner->flush();
+			}
+		};
+	}
+
+	public static function redis(string $prefix, string $host, int $port, string $password, string $database) {
+		$redis = new Redis();
+		$redis->connect($host, $port);
+		if ($password) {
+			$redis->auth($password);
+		}
+		if (!$redis->select($database)) {
+			throw new RuntimeException('Unable to connect to Redis!');
+		}
+
+		return new class($prefix, $redis) implements CacheDriver {
+			private string $prefix;
+			private Redis $inner;
+
+			public function __construct(string $prefix, Redis $inner) {
+				$$this->prefix = $prefix;
+				$this->inner = $inner;
+			}
+
+			public function get(string $key): mixed {
+				$ret = $this->inner->get($this->prefix . $key);
+				if ($ret === false) {
+					return null;
+				}
+				return json_decode($ret, true);
+			}
+
+			public function set(string $key, mixed $value, mixed $expires = false): void {
+				if ($expires === false) {
+					$this->inner->set($this->prefix . $key, json_encode($value));
+				} else {
+					$expires = $expires * 1000; // Seconds to milliseconds.
+					$this->inner->setex($this->prefix . $key, $expires, json_encode($value));
+				}
+			}
+
+			public function delete(string $key): void {
+				$this->inner->del($this->prefix . $key);
+			}
+
+			public function flush(): void {
+				$this->inner->flushDB();
+			}
+		};
+	}
+
+	public static function apcu() {
+		return new class implements CacheDriver {
+			public function get(string $key): mixed {
+				$success = false;
+				$ret = apcu_fetch($key, $success);
+				if ($success === false) {
+					return null;
+				}
+				return $ret;
+			}
+
+			public function set(string $key, mixed $value, mixed $expires = false): void {
+				apcu_store($key, $value, (int)$expires);
+			}
+
+			public function delete(string $key): void {
+				apcu_delete($key);
+			}
+
+			public function flush(): void {
+				apcu_clear_cache();
+			}
+		};
+	}
+
+	public static function filesystem(string $prefix, string $base_path) {
+		if ($base_path[strlen($base_path) - 1] !== '/') {
+			$base_path = "$base_path/";
+		}
+
+		if (!is_dir($base_path)) {
+			throw new RuntimeException("$base_path is not a directory!");
+		}
+
+		if (!is_writable($base_path)) {
+			throw new RuntimeException("$base_path is not writable!");
+		}
+
+		return new class($prefix, $base_path) implements CacheDriver {
+			private string $prefix;
+			private string $base_path;
+
+
+			private function prepareKey(string $key): string {
+				$key = str_replace('/', '::', $key);
+				$key = str_replace("\0", '', $key);
+				return $this->prefix . $key;
+			}
+
+			public function __construct(string $prefix, string $base_path) {
+				$this->prefix = $prefix;
+				$this->base_path = $base_path;
+			}
+
+			public function get(string $key): mixed {
+				$key = $this->prepareKey($key);
+
+				$fd = fopen("$this->base_path/$key", 'r');
+				if ($fd === false) {
+					return null;
+				}
+
+				$data = stream_get_contents("$this->base_path/$key");
+				fclose($fd);
+				return json_decode($data, true);
+			}
+
+			public function set(string $key, mixed $value, mixed $expires = false): void {
+				$key = $this->prepareKey($key);
+
+				$data = json_encode($value);
+				file_put_contents("$this->base_path/$key", $data);
+			}
+
+			public function delete(string $key): void {
+				$key = $this->prepareKey($key);
+
+				@unlink("$this->base_path/$key");
+			}
+
+			public function flush(): void {
+				$files = glob("$this->base_path/$this->prefix*");
+				foreach ($files as $file) {
+					@unlink($file);
+				}
+			}
+		};
+	}
+
+	public static function phpArray() {
+		return new class implements CacheDriver {
+			private static array $inner = [];
+
+			public function get(string $key): mixed {
+				return isset(self::$inner[$key]) ? self::$inner[$key] : null;
+			}
+
+			public function set(string $key, mixed $value, mixed $expires = false): void {
+				self::$inner[$key] = $value;
+			}
+
+			public function delete(string $key): void {
+				unset(self::$inner[$key]);
+			}
+
+			public function flush(): void {
+				self::$inner = [];
+			}
+		};
+	}
+
+	/**
+	 * No-op cache. Useful for testing.
+	 */
+	public static function none() {
+		return new class implements CacheDriver {
+			public function get(string $key): mixed {
+				return null;
+			}
+
+			public function set(string $key, mixed $value, mixed $expires = false): void {
+				// No-op.
+			}
+
+			public function delete(string $key): void {
+				// No-op.
+			}
+
+			public function flush(): void {
+				// No-op.
+			}
+		};
+	}
+}
+
+interface CacheDriver {
+	/**
+	 * Get the value of associated with the key.
+	 *
+	 * @param string $key The key of the value.
+	 * @return mixed|null The value associated with the key, or null if there is none.
+	 */
+	public function get(string $key): mixed;
+
+	/**
+	 * Set a key-value pair.
+	 *
+	 * @param string $key The key.
+	 * @param mixed $value The value.
+	 * @param int|false $expires After how many seconds the pair will expire. Use false or ignore this parameter to keep
+	 *                           the value until it gets evicted to make space for more items. Some drivers will always
+	 *                           ignore this parameter and store the pair until it's removed.
+	 */
+	public function set(string $key, mixed $value, mixed $expires = false): void;
+
+	/**
+	 * Delete a key-value pair.
+	 *
+	 * @param string $key The key.
+	 */
+	public function delete(string $key): void;
+
+	/**
+	 * Delete all the key-value pairs.
+	 */
+	public function flush(): void;
+}

From b57d9bfbb3b581cf63f34c831c760b632d903c8c Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@mailu.io>
Date: Thu, 11 Apr 2024 19:20:19 +0200
Subject: [PATCH 02/11] cache: implement cache locking for filesystem cache and
 give it multiprocess support

---
 inc/driver/cache-driver.php | 55 +++++++++++++++++++++++++++++++------
 1 file changed, 47 insertions(+), 8 deletions(-)

diff --git a/inc/driver/cache-driver.php b/inc/driver/cache-driver.php
index b5279d82..0718ad86 100644
--- a/inc/driver/cache-driver.php
+++ b/inc/driver/cache-driver.php
@@ -122,7 +122,7 @@ class CacheDrivers {
 		};
 	}
 
-	public static function filesystem(string $prefix, string $base_path) {
+	public static function filesystem(string $prefix, string $base_path, string $lock_file) {
 		if ($base_path[strlen($base_path) - 1] !== '/') {
 			$base_path = "$base_path/";
 		}
@@ -135,9 +135,17 @@ class CacheDrivers {
 			throw new RuntimeException("$base_path is not writable!");
 		}
 
-		return new class($prefix, $base_path) implements CacheDriver {
+		$lock_file = $base_path . $lock_file;
+
+		$lock_fd = fopen($lock_file, 'w');
+		if ($lock_fd === false) {
+			throw new RuntimeException('Unable to open the lock file!');
+		}
+
+		$ret = new class($prefix, $base_path, $lock_file) implements CacheDriver {
 			private string $prefix;
 			private string $base_path;
+			private mixed $lock_fd;
 
 
 			private function prepareKey(string $key): string {
@@ -146,21 +154,38 @@ class CacheDrivers {
 				return $this->prefix . $key;
 			}
 
-			public function __construct(string $prefix, string $base_path) {
+			private function sharedLockCache(): void {
+				flock($this->lock_fd, LOCK_SH);
+			}
+
+			private function exclusiveLockCache(): void {
+				flock($this->lock_fd, LOCK_EX);
+			}
+
+			private function unlockCache(): void {
+				flock($this->lock_fd, LOCK_UN);
+			}
+
+			public function __construct(string $prefix, string $base_path, mixed $lock_fd) {
 				$this->prefix = $prefix;
 				$this->base_path = $base_path;
+				$this->lock_fd = $lock_fd;
 			}
 
 			public function get(string $key): mixed {
 				$key = $this->prepareKey($key);
 
-				$fd = fopen("$this->base_path/$key", 'r');
+				$this->sharedLockCache();
+
+				$fd = fopen($this->base_path . $key, 'r');
 				if ($fd === false) {
+					$this->unlockCache();
 					return null;
 				}
 
-				$data = stream_get_contents("$this->base_path/$key");
+				$data = stream_get_contents($fd);
 				fclose($fd);
+				$this->unlockCache();
 				return json_decode($data, true);
 			}
 
@@ -168,22 +193,36 @@ class CacheDrivers {
 				$key = $this->prepareKey($key);
 
 				$data = json_encode($value);
-				file_put_contents("$this->base_path/$key", $data);
+				$this->exclusiveLockCache();
+				file_put_contents($this->base_path . $key, $data);
+				$this->unlockCache();
 			}
 
 			public function delete(string $key): void {
 				$key = $this->prepareKey($key);
 
-				@unlink("$this->base_path/$key");
+				$this->exclusiveLockCache();
+				@unlink($this->base_path . $key);
+				$this->unlockCache();
 			}
 
 			public function flush(): void {
-				$files = glob("$this->base_path/$this->prefix*");
+				$this->exclusiveLockCache();
+				$files = glob($this->base_path . $this->prefix . '*', GLOB_NOSORT);
 				foreach ($files as $file) {
 					@unlink($file);
 				}
+				$this->unlockCache();
+			}
+
+			public function close() {
+				fclose($this->lock_fd);
 			}
 		};
+
+		register_shutdown_function([$ret, 'close']);
+
+		return $ret;
 	}
 
 	public static function phpArray() {

From 5ea42fa0e2bb3c61c711a0461774e5d3b1b8f875 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@mailu.io>
Date: Thu, 11 Apr 2024 18:19:18 +0200
Subject: [PATCH 03/11] config.php: update cache documentation

---
 inc/config.php | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/inc/config.php b/inc/config.php
index 11ac8809..d958d617 100644
--- a/inc/config.php
+++ b/inc/config.php
@@ -139,17 +139,26 @@
 
 	/*
 	 * On top of the static file caching system, you can enable the additional caching system which is
-	 * designed to minimize SQL queries and can significantly increase speed when posting or using the
-	 * moderator interface. APC is the recommended method of caching.
+	 * designed to minimize request processing can significantly increase speed when posting or using
+	 * the moderator interface.
 	 *
 	 * https://github.com/vichan-devel/vichan/wiki/cache
 	 */
 
+	// Uses a PHP array. MUST NOT be used in multiprocess environments.
 	$config['cache']['enabled'] = 'php';
+	// The recommended in-memory method of caching. Requires the extension. Due to how APCu works, this should be
+	// disabled when you run tools from the cli.
 	// $config['cache']['enabled'] = 'apcu';
+	// The Memcache server. Requires the memcached extension, with a final D.
 	// $config['cache']['enabled'] = 'memcached';
+	// The Redis server. Requires the extension.
 	// $config['cache']['enabled'] = 'redis';
+	// Use the local cache folder. Slower than native but available out of the box and compatible with multiprocess
+	// environments. You can mount a ram-based filesystem in the cache directory to improve performance.
 	// $config['cache']['enabled'] = 'fs';
+	// Technically available, offers a no-op fake cache. Don't use this outside of testing or debugging.
+	// $config['cache']['enabled'] = 'none';
 
 	// Timeout for cached objects such as posts and HTML.
 	$config['cache']['timeout'] = 60 * 60 * 48; // 48 hours

From 66d2f901718dcdb3e88cb9683b3cd02e5f9a3100 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@skiff.com>
Date: Fri, 20 Sep 2024 19:44:50 +0200
Subject: [PATCH 04/11] cache-driver.php: filesystem handle expired values.

---
 inc/driver/cache-driver.php | 55 ++++++++++++++++++++++++++++++++++---
 1 file changed, 51 insertions(+), 4 deletions(-)

diff --git a/inc/driver/cache-driver.php b/inc/driver/cache-driver.php
index 0718ad86..672d7b92 100644
--- a/inc/driver/cache-driver.php
+++ b/inc/driver/cache-driver.php
@@ -122,7 +122,7 @@ class CacheDrivers {
 		};
 	}
 
-	public static function filesystem(string $prefix, string $base_path, string $lock_file) {
+	public static function filesystem(string $prefix, string $base_path, string $lock_file, int|false $collect_chance_den) {
 		if ($base_path[strlen($base_path) - 1] !== '/') {
 			$base_path = "$base_path/";
 		}
@@ -146,6 +146,7 @@ class CacheDrivers {
 			private string $prefix;
 			private string $base_path;
 			private mixed $lock_fd;
+			private int|false $collect_chance_den;
 
 
 			private function prepareKey(string $key): string {
@@ -166,10 +167,34 @@ class CacheDrivers {
 				flock($this->lock_fd, LOCK_UN);
 			}
 
-			public function __construct(string $prefix, string $base_path, mixed $lock_fd) {
+			private function collectImpl(): int {
+				// A read lock is ok, since it's alright if we delete expired items from under the feet of other processes.
+				$files = glob($this->base_path . $this->prefix . '*', GLOB_NOSORT);
+				$count = 0;
+				foreach ($files as $file) {
+					$data = file_get_contents($file);
+					$wrapped = json_decode($data, true, 512, JSON_THROW_ON_ERROR);
+					if ($wrapped['expires'] !== false && $wrapped['expires'] <= time()) {
+						if (@unlink($file)) {
+							$count++;
+						}
+					}
+				}
+				return $count;
+			}
+
+			private function maybeCollect() {
+				if ($this->collect_chance_den !== false && rand(0, $this->collect_chance_den) === 0) {
+					$this->collect_chance_den = false; // Collect only once per instance (aka process$this->collect_chance_den !== false$this->collect_chance_den !== false).
+					$this->collectImpl();
+				}
+			}
+
+			public function __construct(string $prefix, string $base_path, mixed $lock_fd, int|false $collect_chance_den) {
 				$this->prefix = $prefix;
 				$this->base_path = $base_path;
 				$this->lock_fd = $lock_fd;
+				$this->collect_chance_den = $collect_chance_den;
 			}
 
 			public function get(string $key): mixed {
@@ -185,16 +210,30 @@ class CacheDrivers {
 
 				$data = stream_get_contents($fd);
 				fclose($fd);
+				$this->maybeCollect();
 				$this->unlockCache();
-				return json_decode($data, true);
+				$wrapped = json_decode($data, true, 512, JSON_THROW_ON_ERROR);
+
+				if ($wrapped['expires'] !== false && $wrapped['expires'] <= time()) {
+					// Already, expired, pretend it doesn't exist.
+					return null;
+				} else {
+					return $wrapped['inner'];
+				}
 			}
 
 			public function set(string $key, mixed $value, mixed $expires = false): void {
 				$key = $this->prepareKey($key);
 
-				$data = json_encode($value);
+				$wrapped = [
+					'expires' => $expires ? time() + $expires : false,
+					'inner' => $value
+				];
+
+				$data = json_encode($wrapped);
 				$this->exclusiveLockCache();
 				file_put_contents($this->base_path . $key, $data);
+				$this->maybeCollect();
 				$this->unlockCache();
 			}
 
@@ -203,9 +242,17 @@ class CacheDrivers {
 
 				$this->exclusiveLockCache();
 				@unlink($this->base_path . $key);
+				$this->maybeCollect();
 				$this->unlockCache();
 			}
 
+			public function collect() {
+				$this->sharedLockCache();
+				$count = $this->collectImpl();
+				$this->unlockCache();
+				return $count;
+			}
+
 			public function flush(): void {
 				$this->exclusiveLockCache();
 				$files = glob($this->base_path . $this->prefix . '*', GLOB_NOSORT);

From 3d406aeab2343c23b694d5d84b20fc359a7254e5 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@mailu.io>
Date: Wed, 2 Oct 2024 21:36:28 +0200
Subject: [PATCH 05/11] cache-driver.php: move to Data

---
 inc/{driver => Data/Driver}/cache-driver.php | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
 rename inc/{driver => Data/Driver}/cache-driver.php (99%)

diff --git a/inc/driver/cache-driver.php b/inc/Data/Driver/cache-driver.php
similarity index 99%
rename from inc/driver/cache-driver.php
rename to inc/Data/Driver/cache-driver.php
index 672d7b92..b943ee71 100644
--- a/inc/driver/cache-driver.php
+++ b/inc/Data/Driver/cache-driver.php
@@ -1,5 +1,5 @@
 <?php
-namespace Vichan\Driver;
+namespace Vichan\Data\Driver;
 
 use RuntimeException;
 

From ace2f2e83b21972da252e06b856d8d2a97e5de68 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@mailu.io>
Date: Wed, 2 Oct 2024 21:49:51 +0200
Subject: [PATCH 06/11] driver: break up cache drivers

---
 inc/Data/Driver/ApcuCacheDriver.php     |  28 ++
 inc/Data/Driver/ArrayCacheDriver.php    |  28 ++
 inc/Data/Driver/CacheDriver.php         |  38 +++
 inc/Data/Driver/FsCachedriver.php       | 150 ++++++++++
 inc/Data/Driver/MemcacheCacheDriver.php |  43 +++
 inc/Data/Driver/NoneCacheDriver.php     |  26 ++
 inc/Data/Driver/RedisCacheDriver.php    |  48 ++++
 inc/Data/Driver/cache-driver.php        | 352 ------------------------
 8 files changed, 361 insertions(+), 352 deletions(-)
 create mode 100644 inc/Data/Driver/ApcuCacheDriver.php
 create mode 100644 inc/Data/Driver/ArrayCacheDriver.php
 create mode 100644 inc/Data/Driver/CacheDriver.php
 create mode 100644 inc/Data/Driver/FsCachedriver.php
 create mode 100644 inc/Data/Driver/MemcacheCacheDriver.php
 create mode 100644 inc/Data/Driver/NoneCacheDriver.php
 create mode 100644 inc/Data/Driver/RedisCacheDriver.php
 delete mode 100644 inc/Data/Driver/cache-driver.php

diff --git a/inc/Data/Driver/ApcuCacheDriver.php b/inc/Data/Driver/ApcuCacheDriver.php
new file mode 100644
index 00000000..a39bb656
--- /dev/null
+++ b/inc/Data/Driver/ApcuCacheDriver.php
@@ -0,0 +1,28 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+class ApcuCacheDriver implements CacheDriver {
+	public function get(string $key): mixed {
+		$success = false;
+		$ret = \apcu_fetch($key, $success);
+		if ($success === false) {
+			return null;
+		}
+		return $ret;
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		\apcu_store($key, $value, (int)$expires);
+	}
+
+	public function delete(string $key): void {
+		\apcu_delete($key);
+	}
+
+	public function flush(): void {
+		\apcu_clear_cache();
+	}
+}
diff --git a/inc/Data/Driver/ArrayCacheDriver.php b/inc/Data/Driver/ArrayCacheDriver.php
new file mode 100644
index 00000000..bb0cd310
--- /dev/null
+++ b/inc/Data/Driver/ArrayCacheDriver.php
@@ -0,0 +1,28 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+/**
+ * A simple process-wide PHP array.
+ */
+class ArrayCacheDriver implements CacheDriver {
+	private static array $inner = [];
+
+	public function get(string $key): mixed {
+		return isset(self::$inner[$key]) ? self::$inner[$key] : null;
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		self::$inner[$key] = $value;
+	}
+
+	public function delete(string $key): void {
+		unset(self::$inner[$key]);
+	}
+
+	public function flush(): void {
+		self::$inner = [];
+	}
+}
diff --git a/inc/Data/Driver/CacheDriver.php b/inc/Data/Driver/CacheDriver.php
new file mode 100644
index 00000000..083ed652
--- /dev/null
+++ b/inc/Data/Driver/CacheDriver.php
@@ -0,0 +1,38 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+interface CacheDriver {
+	/**
+	 * Get the value of associated with the key.
+	 *
+	 * @param string $key The key of the value.
+	 * @return mixed|null The value associated with the key, or null if there is none.
+	 */
+	public function get(string $key): mixed;
+
+	/**
+	 * Set a key-value pair.
+	 *
+	 * @param string $key The key.
+	 * @param mixed $value The value.
+	 * @param int|false $expires After how many seconds the pair will expire. Use false or ignore this parameter to keep
+	 *                           the value until it gets evicted to make space for more items. Some drivers will always
+	 *                           ignore this parameter and store the pair until it's removed.
+	 */
+	public function set(string $key, mixed $value, mixed $expires = false): void;
+
+	/**
+	 * Delete a key-value pair.
+	 *
+	 * @param string $key The key.
+	 */
+	public function delete(string $key): void;
+
+	/**
+	 * Delete all the key-value pairs.
+	 */
+	public function flush(): void;
+}
diff --git a/inc/Data/Driver/FsCachedriver.php b/inc/Data/Driver/FsCachedriver.php
new file mode 100644
index 00000000..f7f0e028
--- /dev/null
+++ b/inc/Data/Driver/FsCachedriver.php
@@ -0,0 +1,150 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+class FsCacheDriver implements CacheDriver {
+	private string $prefix;
+	private string $base_path;
+	private mixed $lock_fd;
+	private int|false $collect_chance_den;
+
+
+	private function prepareKey(string $key): string {
+		$key = \str_replace('/', '::', $key);
+		$key = \str_replace("\0", '', $key);
+		return $this->prefix . $key;
+	}
+
+	private function sharedLockCache(): void {
+		\flock($this->lock_fd, LOCK_SH);
+	}
+
+	private function exclusiveLockCache(): void {
+		\flock($this->lock_fd, LOCK_EX);
+	}
+
+	private function unlockCache(): void {
+		\flock($this->lock_fd, LOCK_UN);
+	}
+
+	private function collectImpl(): int {
+		// A read lock is ok, since it's alright if we delete expired items from under the feet of other processes.
+		$files = \glob($this->base_path . $this->prefix . '*', \GLOB_NOSORT);
+		$count = 0;
+		foreach ($files as $file) {
+			$data = \file_get_contents($file);
+			$wrapped = \json_decode($data, true, 512, \JSON_THROW_ON_ERROR);
+			if ($wrapped['expires'] !== false && $wrapped['expires'] <= \time()) {
+				if (@\unlink($file)) {
+					$count++;
+				}
+			}
+		}
+		return $count;
+	}
+
+	private function maybeCollect(): void {
+		if ($this->collect_chance_den !== false && \mt_rand(0, $this->collect_chance_den - 1) === 0) {
+			$this->collect_chance_den = false; // Collect only once per instance (aka process).
+			$this->collectImpl();
+		}
+	}
+
+	public function __construct(string $prefix, string $base_path, string $lock_file, int|false $collect_chance_den) {
+		if ($base_path[\strlen($base_path) - 1] !== '/') {
+			$base_path = "$base_path/";
+		}
+
+		if (!\is_dir($base_path)) {
+			throw new \RuntimeException("$base_path is not a directory!");
+		}
+
+		if (!\is_writable($base_path)) {
+			throw new \RuntimeException("$base_path is not writable!");
+		}
+
+		$this->lock_fd = \fopen($base_path . $lock_file, 'w');
+		if ($this->lock_fd === false) {
+			throw new \RuntimeException('Unable to open the lock file!');
+		}
+
+		$this->prefix = $prefix;
+		$this->base_path = $base_path;
+		$this->collect_chance_den = $collect_chance_den;
+	}
+
+	public function __destruct() {
+		$this->close();
+	}
+
+	public function get(string $key): mixed {
+		$key = $this->prepareKey($key);
+
+		$this->sharedLockCache();
+
+		$fd = \fopen($this->base_path . $key, 'r');
+		if ($fd === false) {
+			$this->unlockCache();
+			return null;
+		}
+
+		$data = \stream_get_contents($fd);
+		\fclose($fd);
+		$this->maybeCollect();
+		$this->unlockCache();
+		$wrapped = \json_decode($data, true, 512, \JSON_THROW_ON_ERROR);
+
+		if ($wrapped['expires'] !== false && $wrapped['expires'] <= \time()) {
+			// Already expired, leave it there since we already released the lock and pretend it doesn't exist.
+			return null;
+		} else {
+			return $wrapped['inner'];
+		}
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		$key = $this->prepareKey($key);
+
+		$wrapped = [
+			'expires' => $expires ? \time() + $expires : false,
+			'inner' => $value
+		];
+
+		$data = \json_encode($wrapped);
+		$this->exclusiveLockCache();
+		\file_put_contents($this->base_path . $key, $data);
+		$this->maybeCollect();
+		$this->unlockCache();
+	}
+
+	public function delete(string $key): void {
+		$key = $this->prepareKey($key);
+
+		$this->exclusiveLockCache();
+		@\unlink($this->base_path . $key);
+		$this->maybeCollect();
+		$this->unlockCache();
+	}
+
+	public function collect(): int {
+		$this->sharedLockCache();
+		$count = $this->collectImpl();
+		$this->unlockCache();
+		return $count;
+	}
+
+	public function flush(): void {
+		$this->exclusiveLockCache();
+		$files = \glob($this->base_path . $this->prefix . '*', \GLOB_NOSORT);
+		foreach ($files as $file) {
+			@\unlink($file);
+		}
+		$this->unlockCache();
+	}
+
+	public function close(): void {
+		\fclose($this->lock_fd);
+	}
+}
diff --git a/inc/Data/Driver/MemcacheCacheDriver.php b/inc/Data/Driver/MemcacheCacheDriver.php
new file mode 100644
index 00000000..04f62895
--- /dev/null
+++ b/inc/Data/Driver/MemcacheCacheDriver.php
@@ -0,0 +1,43 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+class MemcachedCacheDriver implements CacheDriver {
+	private \Memcached $inner;
+
+	public function __construct(string $prefix, string $memcached_server) {
+		$this->inner = new \Memcached();
+		if (!$this->inner->setOption(\Memcached::OPT_BINARY_PROTOCOL, true)) {
+			throw new \RuntimeException('Unable to set the memcached protocol!');
+		}
+		if (!$this->inner->setOption(\Memcached::OPT_PREFIX_KEY, $prefix)) {
+			throw new \RuntimeException('Unable to set the memcached prefix!');
+		}
+		if (!$this->inner->addServers($memcached_server)) {
+			throw new \RuntimeException('Unable to add the memcached server!');
+		}
+	}
+
+	public function get(string $key): mixed {
+		$ret = $this->inner->get($key);
+		// If the returned value is false but the retrival was a success, then the value stored was a boolean false.
+		if ($ret === false && $this->inner->getResultCode() !== \Memcached::RES_SUCCESS) {
+			return null;
+		}
+		return $ret;
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		$this->inner->set($key, $value, (int)$expires);
+	}
+
+	public function delete(string $key): void {
+		$this->inner->delete($key);
+	}
+
+	public function flush(): void {
+		$this->inner->flush();
+	}
+}
diff --git a/inc/Data/Driver/NoneCacheDriver.php b/inc/Data/Driver/NoneCacheDriver.php
new file mode 100644
index 00000000..8b260a50
--- /dev/null
+++ b/inc/Data/Driver/NoneCacheDriver.php
@@ -0,0 +1,26 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+/**
+ * No-op cache. Useful for testing.
+ */
+class NoneCacheDriver implements CacheDriver {
+	public function get(string $key): mixed {
+		return null;
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		// No-op.
+	}
+
+	public function delete(string $key): void {
+		// No-op.
+	}
+
+	public function flush(): void {
+		// No-op.
+	}
+}
diff --git a/inc/Data/Driver/RedisCacheDriver.php b/inc/Data/Driver/RedisCacheDriver.php
new file mode 100644
index 00000000..46e602d4
--- /dev/null
+++ b/inc/Data/Driver/RedisCacheDriver.php
@@ -0,0 +1,48 @@
+<?php
+namespace Vichan\Data\Driver;
+
+defined('TINYBOARD') or exit;
+
+
+class RedisCacheDriver implements CacheDriver {
+	private string $prefix;
+	private \Redis $inner;
+
+	public function __construct(string $prefix, string $host, int $port, ?string $password, string $database) {
+		$this->inner = new \Redis();
+		$this->inner->connect($host, $port);
+		if ($password) {
+			$this->inner->auth($password);
+		}
+		if (!$this->inner->select($database)) {
+			throw new \RuntimeException('Unable to connect to Redis!');
+		}
+
+		$$this->prefix = $prefix;
+	}
+
+	public function get(string $key): mixed {
+		$ret = $this->inner->get($this->prefix . $key);
+		if ($ret === false) {
+			return null;
+		}
+		return \json_decode($ret, true);
+	}
+
+	public function set(string $key, mixed $value, mixed $expires = false): void {
+		if ($expires === false) {
+			$this->inner->set($this->prefix . $key, \json_encode($value));
+		} else {
+			$expires = $expires * 1000; // Seconds to milliseconds.
+			$this->inner->setex($this->prefix . $key, $expires, \json_encode($value));
+		}
+	}
+
+	public function delete(string $key): void {
+		$this->inner->del($this->prefix . $key);
+	}
+
+	public function flush(): void {
+		$this->inner->flushDB();
+	}
+}
diff --git a/inc/Data/Driver/cache-driver.php b/inc/Data/Driver/cache-driver.php
deleted file mode 100644
index b943ee71..00000000
--- a/inc/Data/Driver/cache-driver.php
+++ /dev/null
@@ -1,352 +0,0 @@
-<?php
-namespace Vichan\Data\Driver;
-
-use RuntimeException;
-
-defined('TINYBOARD') or exit;
-
-/**
- * PHP has no nested or private classes support.
- */
-class CacheDrivers {
-	public static function memcached(string $prefix, string $memcached_server) {
-		$memcached = new Memcached();
-		if (!$memcached->setOption(Memcached::OPT_BINARY_PROTOCOL, true)) {
-			throw new RuntimeException('Unable to set the memcached protocol!');
-		}
-		if (!$memcached->setOption(Memcached::OPT_PREFIX_KEY, $prefix)) {
-			throw new RuntimeException('Unable to set the memcached prefix!');
-		}
-		if (!$memcached->addServers($memcached_server)) {
-			throw new RuntimeException('Unable to add the memcached server!');
-		}
-
-		return new class($memcached) implements CacheDriver {
-			private Memcached $inner;
-
-			public function __construct(Memcached $inner) {
-				$this->inner = $inner;
-			}
-
-			public function get(string $key): mixed {
-				$ret = $this->inner->get($key);
-				// If the returned value is false but the retrival was a success, then the value stored was a boolean false.
-				if ($ret === false && $this->inner->getResultCode() !== Memcached::RES_SUCCESS) {
-					return null;
-				}
-				return $ret;
-			}
-
-			public function set(string $key, mixed $value, mixed $expires = false): void {
-				$this->inner->set($key, $value, (int)$expires);
-			}
-
-			public function delete(string $key): void {
-				$this->inner->delete($key);
-			}
-
-			public function flush(): void {
-				$this->inner->flush();
-			}
-		};
-	}
-
-	public static function redis(string $prefix, string $host, int $port, string $password, string $database) {
-		$redis = new Redis();
-		$redis->connect($host, $port);
-		if ($password) {
-			$redis->auth($password);
-		}
-		if (!$redis->select($database)) {
-			throw new RuntimeException('Unable to connect to Redis!');
-		}
-
-		return new class($prefix, $redis) implements CacheDriver {
-			private string $prefix;
-			private Redis $inner;
-
-			public function __construct(string $prefix, Redis $inner) {
-				$$this->prefix = $prefix;
-				$this->inner = $inner;
-			}
-
-			public function get(string $key): mixed {
-				$ret = $this->inner->get($this->prefix . $key);
-				if ($ret === false) {
-					return null;
-				}
-				return json_decode($ret, true);
-			}
-
-			public function set(string $key, mixed $value, mixed $expires = false): void {
-				if ($expires === false) {
-					$this->inner->set($this->prefix . $key, json_encode($value));
-				} else {
-					$expires = $expires * 1000; // Seconds to milliseconds.
-					$this->inner->setex($this->prefix . $key, $expires, json_encode($value));
-				}
-			}
-
-			public function delete(string $key): void {
-				$this->inner->del($this->prefix . $key);
-			}
-
-			public function flush(): void {
-				$this->inner->flushDB();
-			}
-		};
-	}
-
-	public static function apcu() {
-		return new class implements CacheDriver {
-			public function get(string $key): mixed {
-				$success = false;
-				$ret = apcu_fetch($key, $success);
-				if ($success === false) {
-					return null;
-				}
-				return $ret;
-			}
-
-			public function set(string $key, mixed $value, mixed $expires = false): void {
-				apcu_store($key, $value, (int)$expires);
-			}
-
-			public function delete(string $key): void {
-				apcu_delete($key);
-			}
-
-			public function flush(): void {
-				apcu_clear_cache();
-			}
-		};
-	}
-
-	public static function filesystem(string $prefix, string $base_path, string $lock_file, int|false $collect_chance_den) {
-		if ($base_path[strlen($base_path) - 1] !== '/') {
-			$base_path = "$base_path/";
-		}
-
-		if (!is_dir($base_path)) {
-			throw new RuntimeException("$base_path is not a directory!");
-		}
-
-		if (!is_writable($base_path)) {
-			throw new RuntimeException("$base_path is not writable!");
-		}
-
-		$lock_file = $base_path . $lock_file;
-
-		$lock_fd = fopen($lock_file, 'w');
-		if ($lock_fd === false) {
-			throw new RuntimeException('Unable to open the lock file!');
-		}
-
-		$ret = new class($prefix, $base_path, $lock_file) implements CacheDriver {
-			private string $prefix;
-			private string $base_path;
-			private mixed $lock_fd;
-			private int|false $collect_chance_den;
-
-
-			private function prepareKey(string $key): string {
-				$key = str_replace('/', '::', $key);
-				$key = str_replace("\0", '', $key);
-				return $this->prefix . $key;
-			}
-
-			private function sharedLockCache(): void {
-				flock($this->lock_fd, LOCK_SH);
-			}
-
-			private function exclusiveLockCache(): void {
-				flock($this->lock_fd, LOCK_EX);
-			}
-
-			private function unlockCache(): void {
-				flock($this->lock_fd, LOCK_UN);
-			}
-
-			private function collectImpl(): int {
-				// A read lock is ok, since it's alright if we delete expired items from under the feet of other processes.
-				$files = glob($this->base_path . $this->prefix . '*', GLOB_NOSORT);
-				$count = 0;
-				foreach ($files as $file) {
-					$data = file_get_contents($file);
-					$wrapped = json_decode($data, true, 512, JSON_THROW_ON_ERROR);
-					if ($wrapped['expires'] !== false && $wrapped['expires'] <= time()) {
-						if (@unlink($file)) {
-							$count++;
-						}
-					}
-				}
-				return $count;
-			}
-
-			private function maybeCollect() {
-				if ($this->collect_chance_den !== false && rand(0, $this->collect_chance_den) === 0) {
-					$this->collect_chance_den = false; // Collect only once per instance (aka process$this->collect_chance_den !== false$this->collect_chance_den !== false).
-					$this->collectImpl();
-				}
-			}
-
-			public function __construct(string $prefix, string $base_path, mixed $lock_fd, int|false $collect_chance_den) {
-				$this->prefix = $prefix;
-				$this->base_path = $base_path;
-				$this->lock_fd = $lock_fd;
-				$this->collect_chance_den = $collect_chance_den;
-			}
-
-			public function get(string $key): mixed {
-				$key = $this->prepareKey($key);
-
-				$this->sharedLockCache();
-
-				$fd = fopen($this->base_path . $key, 'r');
-				if ($fd === false) {
-					$this->unlockCache();
-					return null;
-				}
-
-				$data = stream_get_contents($fd);
-				fclose($fd);
-				$this->maybeCollect();
-				$this->unlockCache();
-				$wrapped = json_decode($data, true, 512, JSON_THROW_ON_ERROR);
-
-				if ($wrapped['expires'] !== false && $wrapped['expires'] <= time()) {
-					// Already, expired, pretend it doesn't exist.
-					return null;
-				} else {
-					return $wrapped['inner'];
-				}
-			}
-
-			public function set(string $key, mixed $value, mixed $expires = false): void {
-				$key = $this->prepareKey($key);
-
-				$wrapped = [
-					'expires' => $expires ? time() + $expires : false,
-					'inner' => $value
-				];
-
-				$data = json_encode($wrapped);
-				$this->exclusiveLockCache();
-				file_put_contents($this->base_path . $key, $data);
-				$this->maybeCollect();
-				$this->unlockCache();
-			}
-
-			public function delete(string $key): void {
-				$key = $this->prepareKey($key);
-
-				$this->exclusiveLockCache();
-				@unlink($this->base_path . $key);
-				$this->maybeCollect();
-				$this->unlockCache();
-			}
-
-			public function collect() {
-				$this->sharedLockCache();
-				$count = $this->collectImpl();
-				$this->unlockCache();
-				return $count;
-			}
-
-			public function flush(): void {
-				$this->exclusiveLockCache();
-				$files = glob($this->base_path . $this->prefix . '*', GLOB_NOSORT);
-				foreach ($files as $file) {
-					@unlink($file);
-				}
-				$this->unlockCache();
-			}
-
-			public function close() {
-				fclose($this->lock_fd);
-			}
-		};
-
-		register_shutdown_function([$ret, 'close']);
-
-		return $ret;
-	}
-
-	public static function phpArray() {
-		return new class implements CacheDriver {
-			private static array $inner = [];
-
-			public function get(string $key): mixed {
-				return isset(self::$inner[$key]) ? self::$inner[$key] : null;
-			}
-
-			public function set(string $key, mixed $value, mixed $expires = false): void {
-				self::$inner[$key] = $value;
-			}
-
-			public function delete(string $key): void {
-				unset(self::$inner[$key]);
-			}
-
-			public function flush(): void {
-				self::$inner = [];
-			}
-		};
-	}
-
-	/**
-	 * No-op cache. Useful for testing.
-	 */
-	public static function none() {
-		return new class implements CacheDriver {
-			public function get(string $key): mixed {
-				return null;
-			}
-
-			public function set(string $key, mixed $value, mixed $expires = false): void {
-				// No-op.
-			}
-
-			public function delete(string $key): void {
-				// No-op.
-			}
-
-			public function flush(): void {
-				// No-op.
-			}
-		};
-	}
-}
-
-interface CacheDriver {
-	/**
-	 * Get the value of associated with the key.
-	 *
-	 * @param string $key The key of the value.
-	 * @return mixed|null The value associated with the key, or null if there is none.
-	 */
-	public function get(string $key): mixed;
-
-	/**
-	 * Set a key-value pair.
-	 *
-	 * @param string $key The key.
-	 * @param mixed $value The value.
-	 * @param int|false $expires After how many seconds the pair will expire. Use false or ignore this parameter to keep
-	 *                           the value until it gets evicted to make space for more items. Some drivers will always
-	 *                           ignore this parameter and store the pair until it's removed.
-	 */
-	public function set(string $key, mixed $value, mixed $expires = false): void;
-
-	/**
-	 * Delete a key-value pair.
-	 *
-	 * @param string $key The key.
-	 */
-	public function delete(string $key): void;
-
-	/**
-	 * Delete all the key-value pairs.
-	 */
-	public function flush(): void;
-}

From f138b4b88799f051a5a60bc70c806d600ed25263 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@skiff.com>
Date: Fri, 26 Apr 2024 13:55:58 +0200
Subject: [PATCH 07/11] cache.php: wrap new cache drivers

---
 inc/cache.php | 177 +++++++++++++++-----------------------------------
 1 file changed, 51 insertions(+), 126 deletions(-)

diff --git a/inc/cache.php b/inc/cache.php
index ae788bc1..293660fd 100644
--- a/inc/cache.php
+++ b/inc/cache.php
@@ -4,164 +4,89 @@
  *  Copyright (c) 2010-2013 Tinyboard Development Group
  */
 
+use Vichan\Data\Driver\{CacheDriver, ApcuCacheDriver, ArrayCacheDriver, FsCacheDriver, MemcachedCacheDriver, NoneCacheDriver, RedisCacheDriver};
+
 defined('TINYBOARD') or exit;
 
+
 class Cache {
-	private static $cache;
-	public static function init() {
+	private static function buildCache(): CacheDriver {
 		global $config;
 
 		switch ($config['cache']['enabled']) {
 			case 'memcached':
-				self::$cache = new Memcached();
-				self::$cache->addServers($config['cache']['memcached']);
-				break;
+				return new MemcachedCacheDriver(
+					$config['cache']['prefix'],
+					$config['cache']['memcached']
+				);
 			case 'redis':
-				self::$cache = new Redis();
-				self::$cache->connect($config['cache']['redis'][0], $config['cache']['redis'][1]);
-				if ($config['cache']['redis'][2]) {
-					self::$cache->auth($config['cache']['redis'][2]);
-				}
-				self::$cache->select($config['cache']['redis'][3]) or die('cache select failure');
-				break;
+				return new RedisCacheDriver(
+					$config['cache']['prefix'],
+					$config['cache']['redis'][0],
+					$config['cache']['redis'][1],
+					$config['cache']['redis'][2],
+					$config['cache']['redis'][3]
+				);
+			case 'apcu':
+				return new ApcuCacheDriver;
+			case 'fs':
+				return new FsCacheDriver(
+					$config['cache']['prefix'],
+					"tmp/cache/{$config['cache']['prefix']}",
+					'.lock',
+					$config['auto_maintenance'] ? 1000 : false
+				);
+			case 'none':
+				return new NoneCacheDriver();
 			case 'php':
-				self::$cache = [];
-				break;
+			default:
+				return new ArrayCacheDriver();
 		}
 	}
+
+	public static function getCache(): CacheDriver {
+		static $cache;
+		return $cache ??= self::buildCache();
+	}
+
 	public static function get($key) {
 		global $config, $debug;
 
-		$key = $config['cache']['prefix'] . $key;
-
-		$data = false;
-		switch ($config['cache']['enabled']) {
-			case 'memcached':
-				if (!self::$cache)
-					self::init();
-				$data = self::$cache->get($key);
-				break;
-			case 'apcu':
-				$data = apcu_fetch($key);
-				break;
-			case 'php':
-				$data = isset(self::$cache[$key]) ? self::$cache[$key] : false;
-				break;
-			case 'fs':
-				$key = str_replace('/', '::', $key);
-				$key = str_replace("\0", '', $key);
-				if (!file_exists('tmp/cache/'.$key)) {
-					$data = false;
-				}
-				else {
-					$data = file_get_contents('tmp/cache/'.$key);
-					$data = json_decode($data, true);
-				}
-				break;
-			case 'redis':
-				if (!self::$cache)
-					self::init();
-				$data = json_decode(self::$cache->get($key), true);
-				break;
+		$ret = self::getCache()->get($key);
+		if ($ret === null) {
+			$ret = false;
 		}
 
-		if ($config['debug'])
-			$debug['cached'][] = $key . ($data === false ? ' (miss)' : ' (hit)');
+		if ($config['debug']) {
+			$debug['cached'][] = $config['cache']['prefix'] . $key . ($ret === false ? ' (miss)' : ' (hit)');
+		}
 
-		return $data;
+		return $ret;
 	}
 	public static function set($key, $value, $expires = false) {
 		global $config, $debug;
 
-		$key = $config['cache']['prefix'] . $key;
-
-		if (!$expires)
+		if (!$expires) {
 			$expires = $config['cache']['timeout'];
-
-		switch ($config['cache']['enabled']) {
-			case 'memcached':
-				if (!self::$cache)
-					self::init();
-				self::$cache->set($key, $value, $expires);
-				break;
-			case 'redis':
-				if (!self::$cache)
-					self::init();
-				self::$cache->setex($key, $expires, json_encode($value));
-				break;
-			case 'apcu':
-				apcu_store($key, $value, $expires);
-				break;
-			case 'fs':
-				$key = str_replace('/', '::', $key);
-				$key = str_replace("\0", '', $key);
-				file_put_contents('tmp/cache/'.$key, json_encode($value));
-				break;
-			case 'php':
-				self::$cache[$key] = $value;
-				break;
 		}
 
-		if ($config['debug'])
-			$debug['cached'][] = $key . ' (set)';
+		self::getCache()->set($key, $value, $expires);
+
+		if ($config['debug']) {
+			$debug['cached'][] = $config['cache']['prefix'] . $key . ' (set)';
+		}
 	}
 	public static function delete($key) {
 		global $config, $debug;
 
-		$key = $config['cache']['prefix'] . $key;
+		self::getCache()->delete($key);
 
-		switch ($config['cache']['enabled']) {
-			case 'memcached':
-				if (!self::$cache)
-					self::init();
-				self::$cache->delete($key);
-				break;
-			case 'redis':
-				if (!self::$cache)
-					self::init();
-				self::$cache->del($key);
-				break;
-			case 'apcu':
-				apcu_delete($key);
-				break;
-			case 'fs':
-				$key = str_replace('/', '::', $key);
-				$key = str_replace("\0", '', $key);
-				@unlink('tmp/cache/'.$key);
-				break;
-			case 'php':
-				unset(self::$cache[$key]);
-				break;
+		if ($config['debug']) {
+			$debug['cached'][] = $config['cache']['prefix'] . $key . ' (deleted)';
 		}
-
-		if ($config['debug'])
-			$debug['cached'][] = $key . ' (deleted)';
 	}
 	public static function flush() {
-		global $config;
-
-		switch ($config['cache']['enabled']) {
-			case 'memcached':
-				if (!self::$cache)
-					self::init();
-				return self::$cache->flush();
-			case 'apcu':
-				return apcu_clear_cache('user');
-			case 'php':
-				self::$cache = array();
-				break;
-			case 'fs':
-				$files = glob('tmp/cache/*');
-				foreach ($files as $file) {
-					unlink($file);
-				}
-				break;
-			case 'redis':
-				if (!self::$cache)
-					self::init();
-				return self::$cache->flushDB();
-		}
-
+		self::getCache()->flush();
 		return false;
 	}
 }

From 589435b667626a43c9f79df45621ed23f0b919a8 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@skiff.com>
Date: Sun, 7 Apr 2024 21:10:39 +0200
Subject: [PATCH 08/11] context.php: use shared cache driver

---
 inc/context.php | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/inc/context.php b/inc/context.php
index c3ebef04..e747a68d 100644
--- a/inc/context.php
+++ b/inc/context.php
@@ -83,6 +83,10 @@ function build_context(array $config): Context {
 				$config['captcha']['native']['provider_check'],
 				$config['captcha']['native']['extra']
 			);
+		},
+		CacheDriver::class => function($c) {
+			// Use the global for backwards compatibility.
+			return \cache::getCache();
 		}
 	]);
 }

From 243e4894fa61917bce70dd58409f2a6aa61d09b8 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@skiff.com>
Date: Sun, 7 Apr 2024 23:14:31 +0200
Subject: [PATCH 09/11] Use CacheDriver and Context for mod.php and mod pages

---
 inc/mod/pages.php | 88 ++++++++++++++++++++++++-----------------------
 1 file changed, 45 insertions(+), 43 deletions(-)

diff --git a/inc/mod/pages.php b/inc/mod/pages.php
index ef41da70..8a549481 100644
--- a/inc/mod/pages.php
+++ b/inc/mod/pages.php
@@ -4,8 +4,8 @@
  */
 use Vichan\Context;
 use Vichan\Functions\Format;
-
 use Vichan\Functions\Net;
+use Vichan\Data\Driver\CacheDriver;
 
 defined('TINYBOARD') or exit;
 
@@ -112,25 +112,23 @@ function mod_dashboard(Context $ctx) {
 	$args['boards'] = listBoards();
 
 	if (hasPermission($config['mod']['noticeboard'])) {
-		if (!$config['cache']['enabled'] || !$args['noticeboard'] = cache::get('noticeboard_preview')) {
+		if (!$args['noticeboard'] = $ctx->get(CacheDriver::class)->get('noticeboard_preview')) {
 			$query = prepare("SELECT ``noticeboard``.*, `username` FROM ``noticeboard`` LEFT JOIN ``mods`` ON ``mods``.`id` = `mod` ORDER BY `id` DESC LIMIT :limit");
 			$query->bindValue(':limit', $config['mod']['noticeboard_dashboard'], PDO::PARAM_INT);
 			$query->execute() or error(db_error($query));
 			$args['noticeboard'] = $query->fetchAll(PDO::FETCH_ASSOC);
 
-			if ($config['cache']['enabled'])
-				cache::set('noticeboard_preview', $args['noticeboard']);
+			$ctx->get(CacheDriver::class)->set('noticeboard_preview', $args['noticeboard']);
 		}
 	}
 
-	if (!$config['cache']['enabled'] || ($args['unread_pms'] = cache::get('pm_unreadcount_' . $mod['id'])) === false) {
+	if ($args['unread_pms'] = $ctx->get(CacheDriver::class)->get('pm_unreadcount_' . $mod['id']) === false) {
 		$query = prepare('SELECT COUNT(*) FROM ``pms`` WHERE `to` = :id AND `unread` = 1');
 		$query->bindValue(':id', $mod['id']);
 		$query->execute() or error(db_error($query));
 		$args['unread_pms'] = $query->fetchColumn();
 
-		if ($config['cache']['enabled'])
-			cache::set('pm_unreadcount_' . $mod['id'], $args['unread_pms']);
+		$ctx->get(CacheDriver::class)->set('pm_unreadcount_' . $mod['id'], $args['unread_pms']);
 	}
 
 	$query = query('SELECT COUNT(*) FROM ``reports``') or error(db_error($query));
@@ -384,6 +382,8 @@ function mod_search(Context $ctx, $type, $search_query_escaped, $page_no = 1) {
 function mod_edit_board(Context $ctx, $boardName) {
 	global $board, $config, $mod;
 
+	$cache = $ctx->get(CacheDriver::class);
+
 	if (!openBoard($boardName))
 		error($config['error']['noboard']);
 
@@ -399,10 +399,8 @@ function mod_edit_board(Context $ctx, $boardName) {
 			$query->bindValue(':uri', $board['uri']);
 			$query->execute() or error(db_error($query));
 
-			if ($config['cache']['enabled']) {
-				cache::delete('board_' . $board['uri']);
-				cache::delete('all_boards');
-			}
+			$cache->delete('board_' . $board['uri']);
+			$cache->delete('all_boards');
 
 			modLog('Deleted board: ' . sprintf($config['board_abbreviation'], $board['uri']), false);
 
@@ -467,10 +465,9 @@ function mod_edit_board(Context $ctx, $boardName) {
 			modLog('Edited board information for ' . sprintf($config['board_abbreviation'], $board['uri']), false);
 		}
 
-		if ($config['cache']['enabled']) {
-			cache::delete('board_' . $board['uri']);
-			cache::delete('all_boards');
-		}
+		$cache->delete('board_' . $board['uri']);
+		$cache->delete('all_boards');
+
 
 		Vichan\Functions\Theme\rebuild_themes('boards');
 
@@ -505,6 +502,8 @@ function mod_new_board(Context $ctx) {
 		if (!preg_match('/^' . $config['board_regex'] . '$/u', $_POST['uri']))
 			error(sprintf($config['error']['invalidfield'], 'URI'));
 
+		$cache = $ctx->get(CacheDriver::class);
+
 		$bytes = 0;
 		$chars = preg_split('//u', $_POST['uri'], -1, PREG_SPLIT_NO_EMPTY);
 		foreach ($chars as $char) {
@@ -544,8 +543,8 @@ function mod_new_board(Context $ctx) {
 
 		query($query) or error(db_error());
 
-		if ($config['cache']['enabled'])
-			cache::delete('all_boards');
+		$cache = $ctx->get(CacheDriver::class);
+		$cache->delete('all_boards');
 
 		// Build the board
 		buildIndex();
@@ -590,8 +589,8 @@ function mod_noticeboard(Context $ctx, $page_no = 1) {
 		$query->bindValue(':body', $_POST['body']);
 		$query->execute() or error(db_error($query));
 
-		if ($config['cache']['enabled'])
-			cache::delete('noticeboard_preview');
+		$cache = $ctx->get(CacheDriver::class);
+		$cache->delete('noticeboard_preview');
 
 		modLog('Posted a noticeboard entry');
 
@@ -631,7 +630,7 @@ function mod_noticeboard_delete(Context $ctx, $id) {
 	$config = $ctx->get('config');
 
 	if (!hasPermission($config['mod']['noticeboard_delete']))
-			error($config['error']['noaccess']);
+		error($config['error']['noaccess']);
 
 	$query = prepare('DELETE FROM ``noticeboard`` WHERE `id` = :id');
 	$query->bindValue(':id', $id);
@@ -639,8 +638,8 @@ function mod_noticeboard_delete(Context $ctx, $id) {
 
 	modLog('Deleted a noticeboard entry');
 
-	if ($config['cache']['enabled'])
-		cache::delete('noticeboard_preview');
+	$cache = $ctx->get(CacheDriver::class);
+	$cache->delete('noticeboard_preview');
 
 	header('Location: ?/noticeboard', true, $config['redirect_http']);
 }
@@ -706,7 +705,7 @@ function mod_news_delete(Context $ctx, $id) {
 	$config = $ctx->get('config');
 
 	if (!hasPermission($config['mod']['news_delete']))
-			error($config['error']['noaccess']);
+		error($config['error']['noaccess']);
 
 	$query = prepare('DELETE FROM ``news`` WHERE `id` = :id');
 	$query->bindValue(':id', $id);
@@ -843,7 +842,7 @@ function mod_view_board(Context $ctx, $boardName, $page_no = 1) {
 	}
 
 	$page['pages'] = getPages(true);
-	$page['pages'][$page_no-1]['selected'] = true;
+	$page['pages'][$page_no - 1]['selected'] = true;
 	$page['btn'] = getPageButtons($page['pages'], true);
 	$page['mod'] = true;
 	$page['config'] = $config;
@@ -1042,7 +1041,6 @@ function mod_edit_ban(Context $ctx, $ban_id) {
 		Bans::delete($ban_id);
 
 		header('Location: ?/', true, $config['redirect_http']);
-
 	}
 
 	$args['token'] = make_secure_link_token('edit_ban/' . $ban_id);
@@ -2235,10 +2233,9 @@ function mod_pm(Context $ctx, $id, $reply = false) {
 		$query->bindValue(':id', $id);
 		$query->execute() or error(db_error($query));
 
-		if ($config['cache']['enabled']) {
-			cache::delete('pm_unread_' . $mod['id']);
-			cache::delete('pm_unreadcount_' . $mod['id']);
-		}
+		$cache = $ctx->get(CacheDriver::class);
+		$cache->delete('pm_unread_' . $mod['id']);
+		$cache->delete('pm_unreadcount_' . $mod['id']);
 
 		header('Location: ?/', true, $config['redirect_http']);
 		return;
@@ -2249,10 +2246,9 @@ function mod_pm(Context $ctx, $id, $reply = false) {
 		$query->bindValue(':id', $id);
 		$query->execute() or error(db_error($query));
 
-		if ($config['cache']['enabled']) {
-			cache::delete('pm_unread_' . $mod['id']);
-			cache::delete('pm_unreadcount_' . $mod['id']);
-		}
+		$cache = $ctx->get(CacheDriver::class);
+		$cache->delete('pm_unread_' . $mod['id']);
+		$cache->delete('pm_unreadcount_' . $mod['id']);
 
 		modLog('Read a PM');
 	}
@@ -2339,10 +2335,10 @@ function mod_new_pm(Context $ctx, $username) {
 		$query->bindValue(':time', time());
 		$query->execute() or error(db_error($query));
 
-		if ($config['cache']['enabled']) {
-			cache::delete('pm_unread_' . $id);
-			cache::delete('pm_unreadcount_' . $id);
-		}
+		$cache = $ctx->get(CacheDriver::class);
+
+		$cache->delete('pm_unread_' . $id);
+		$cache->delete('pm_unreadcount_' . $id);
 
 		modLog('Sent a PM to ' . utf8tohtml($username));
 
@@ -2368,6 +2364,8 @@ function mod_rebuild(Context $ctx) {
 	if (!hasPermission($config['mod']['rebuild']))
 		error($config['error']['noaccess']);
 
+	$cache = $ctx->get(CacheDriver::class);
+
 	if (isset($_POST['rebuild'])) {
 		@set_time_limit($config['mod']['rebuild_timelimit']);
 
@@ -2378,7 +2376,7 @@ function mod_rebuild(Context $ctx) {
 		if (isset($_POST['rebuild_cache'])) {
 			if ($config['cache']['enabled']) {
 				$log[] = 'Flushing cache';
-				Cache::flush();
+				$cache->flush();
 			}
 
 			$log[] = 'Clearing template cache';
@@ -2840,6 +2838,8 @@ function mod_theme_configure(Context $ctx, $theme_name) {
 		error($config['error']['invalidtheme']);
 	}
 
+	$cache = $ctx->get(CacheDriver::class);
+
 	if (isset($_POST['install'])) {
 		// Check if everything is submitted
 		foreach ($theme['config'] as &$conf) {
@@ -2868,8 +2868,8 @@ function mod_theme_configure(Context $ctx, $theme_name) {
 		$query->execute() or error(db_error($query));
 
 		// Clean cache
-		Cache::delete("themes");
-		Cache::delete("theme_settings_".$theme_name);
+		$cache->delete("themes");
+		$cache->delete("theme_settings_$theme_name");
 
 		$result = true;
 		$message = false;
@@ -2928,13 +2928,15 @@ function mod_theme_uninstall(Context $ctx, $theme_name) {
 	if (!hasPermission($config['mod']['themes']))
 		error($config['error']['noaccess']);
 
+	$cache = $ctx->get(CacheDriver::class);
+
 	$query = prepare("DELETE FROM ``theme_settings`` WHERE `theme` = :theme");
 	$query->bindValue(':theme', $theme_name);
 	$query->execute() or error(db_error($query));
 
 	// Clean cache
-	Cache::delete("themes");
-	Cache::delete("theme_settings_".$theme_name);
+	$cache->delete("themes");
+	$cache->delete("theme_settings_$theme_name");
 
 	header('Location: ?/themes', true, $config['redirect_http']);
 }
@@ -2959,7 +2961,7 @@ function mod_theme_rebuild(Context $ctx, $theme_name) {
 }
 
 // This needs to be done for `secure` CSRF prevention compatibility, otherwise the $board will be read in as the token if editing global pages.
-function delete_page_base($page = '', $board = false) {
+function delete_page_base(Context $ctx, $page = '', $board = false) {
 	global $config, $mod;
 
 	if (empty($board))

From 003e8f6d3b0a645ccaa4b131fee31e7dc8b91278 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@skiff.com>
Date: Fri, 20 Sep 2024 22:41:51 +0200
Subject: [PATCH 10/11] maintenance.php: delete expired filesystem cache

---
 tools/maintenance.php | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tools/maintenance.php b/tools/maintenance.php
index 33c0a4d4..a869e2fa 100644
--- a/tools/maintenance.php
+++ b/tools/maintenance.php
@@ -21,5 +21,20 @@ echo "Deleted $deleted_count expired antispam in $delta seconds!\n";
 $time_tot = $delta;
 $deleted_tot = $deleted_count;
 
+if ($config['cache']['enabled'] === 'fs') {
+	$fs_cache = new Vichan\Data\Driver\FsCacheDriver(
+		$config['cache']['prefix'],
+		"tmp/cache/{$config['cache']['prefix']}",
+		'.lock',
+		false
+	);
+	$start = microtime(true);
+	$fs_cache->collect();
+	$delta = microtime(true) - $start;
+	echo "Deleted $deleted_count expired filesystem cache items in $delta seconds!\n";
+	$time_tot = $delta;
+	$deleted_tot = $deleted_count;
+}
+
 $time_tot = number_format((float)$time_tot, 4, '.', '');
 modLog("Deleted $deleted_tot expired entries in {$time_tot}s with maintenance tool");

From 115f28807a614b816a6f519a1bfa5160ff95cc38 Mon Sep 17 00:00:00 2001
From: Zankaria <zankaria.auxa@mailu.io>
Date: Sat, 5 Oct 2024 17:31:41 +0200
Subject: [PATCH 11/11] FsCacheDriver.php: collect expired cache items before
 operating on the cache

---
 inc/Data/Driver/FsCachedriver.php | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/inc/Data/Driver/FsCachedriver.php b/inc/Data/Driver/FsCachedriver.php
index f7f0e028..b543cfa6 100644
--- a/inc/Data/Driver/FsCachedriver.php
+++ b/inc/Data/Driver/FsCachedriver.php
@@ -30,7 +30,10 @@ class FsCacheDriver implements CacheDriver {
 	}
 
 	private function collectImpl(): int {
-		// A read lock is ok, since it's alright if we delete expired items from under the feet of other processes.
+		/*
+		 * A read lock is ok, since it's alright if we delete expired items from under the feet of other processes, and
+		 * no other process add new cache items or refresh existing ones.
+		 */
 		$files = \glob($this->base_path . $this->prefix . '*', \GLOB_NOSORT);
 		$count = 0;
 		foreach ($files as $file) {
@@ -84,6 +87,9 @@ class FsCacheDriver implements CacheDriver {
 
 		$this->sharedLockCache();
 
+		// Collect expired items first so if the target key is expired we shortcut to failure in the next lines.
+		$this->maybeCollect();
+
 		$fd = \fopen($this->base_path . $key, 'r');
 		if ($fd === false) {
 			$this->unlockCache();
@@ -92,7 +98,6 @@ class FsCacheDriver implements CacheDriver {
 
 		$data = \stream_get_contents($fd);
 		\fclose($fd);
-		$this->maybeCollect();
 		$this->unlockCache();
 		$wrapped = \json_decode($data, true, 512, \JSON_THROW_ON_ERROR);
 
@@ -114,8 +119,8 @@ class FsCacheDriver implements CacheDriver {
 
 		$data = \json_encode($wrapped);
 		$this->exclusiveLockCache();
-		\file_put_contents($this->base_path . $key, $data);
 		$this->maybeCollect();
+		\file_put_contents($this->base_path . $key, $data);
 		$this->unlockCache();
 	}