Add X13 WebP module for image conversion to next-generation formats

- Implemented the X13Webp class with core functionalities for converting images to WebP format.
- Added support for different PHP versions and defined constants for versioning.
- Included translation strings for various user interface elements and messages.
- Created XML file for module versioning.

modules/x13webp/vendor/rosell-dk/file-util/src/FileExists.php

@@ -0,0 +1,96 @@
+<?php
+
+namespace FileUtil;
+
+use FileUtil\FileExistsUsingExec;
+
+/**
+ * A fileExist function free of deception
+ *
+ * @package    FileUtil
+ * @author     Bjørn Rosell <it@rosell.dk>
+ */
+class FileExists
+{
+
+    private static $lastWarning;
+
+    /**
+     * A warning handler that registers that a warning has occured and suppresses it.
+     *
+     * The function is a callback used with "set_error_handler".
+     * It is declared public because it needs to be accessible from the point where the warning is triggered.
+     *
+     * @param  integer  $errno
+     * @param  string   $errstr
+     * @param  string   $errfile
+     * @param  integer  $errline
+     *
+     * @return void
+     */
+    public static function warningHandler($errno, $errstr, $errfile, $errline)
+    {
+        self::$lastWarning = [$errstr, $errno];
+
+        // Suppress the warning by returning void
+        return;
+    }
+
+    /**
+     * A well behaved replacement for file_exist that throws upon failure rather than emitting a warning.
+     *
+     * @throws \Exception Throws an exception in case file_exists emits a warning
+     * @return boolean  True if file exists. False if it doesn't.
+     */
+    public static function fileExists($path)
+    {
+        // There is a challenges here:
+        // We want to suppress warnings, but at the same time we want to know that it happened.
+        // We achieve this by registering an error handler
+        set_error_handler(
+            array('FileUtil\FileExists', "warningHandler"),
+            E_WARNING | E_USER_WARNING | E_NOTICE | E_USER_NOTICE
+        );
+        self::$lastWarning = null;
+        $found = @file_exists($path);
+
+        // restore previous error handler immediately
+        restore_error_handler();
+
+        // If file_exists returns true, we can rely on there being a file there
+        if ($found) {
+            return true;
+        }
+
+        // file_exists returned false.
+        // this result is only trustworthy if no warning was emitted.
+        if (is_null(self::$lastWarning)) {
+            return false;
+        }
+
+        list($errstr, $errno) = self::$lastWarning;
+        throw new \Exception($errstr, $errno);
+    }
+
+    /**
+     * A fileExist doing the best it can.
+     *
+     * @throws \Exception  If it cannot be determined if the file exists
+     * @return boolean|null  True if file exists. False if it doesn't.
+     */
+    public static function fileExistsTryHarder($path)
+    {
+        try {
+            $result = self::fileExists($path);
+        } catch (\Exception $e) {
+            try {
+                $result = FileExistsUsingExec::fileExists($path);
+            } catch (\Exception $e) {
+                throw new \Exception('Cannot determine if file exists or not');
+            } catch (\Throwable $e) {
+                throw new \Exception('Cannot determine if file exists or not');
+            }
+        }
+        return $result;
+    }
+}

modules/x13webp/vendor/rosell-dk/file-util/src/FileExistsUsingExec.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace FileUtil;
+
+use ExecWithFallback\ExecWithFallback;
+
+/**
+ * A fileExist implementation using exec()
+ *
+ * @package    FileUtil
+ * @author     Bjørn Rosell <it@rosell.dk>
+ */
+class FileExistsUsingExec
+{
+
+    /**
+     * A fileExist based on an exec call.
+     *
+     * @throws \Exception  If exec cannot be called
+     * @return boolean|null  True if file exists. False if it doesn't.
+     */
+    public static function fileExists($path)
+    {
+        if (!ExecWithFallback::anyAvailable()) {
+            throw new \Exception(
+                'cannot determine if file exists using exec() or similar - the function is unavailable'
+            );
+        }
+
+        // Lets try to find out by executing "ls path/to/cwebp"
+        ExecWithFallback::exec('ls ' . $path, $output, $returnCode);
+        if (($returnCode == 0) && (isset($output[0]))) {
+            return true;
+        }
+
+        // We assume that "ls" command is general available!
+        // As that failed, we can conclude the file does not exist.
+        return false;
+    }
+}

modules/x13webp/vendor/rosell-dk/file-util/src/PathValidator.php

@@ -0,0 +1,70 @@
+<?php
+
+namespace FileUtil;
+
+use FileUtil\FileExists;
+
+/**
+ *
+ *
+ * @package    FileUtil
+ * @author     Bjørn Rosell <it@rosell.dk>
+ */
+class PathValidator
+{
+    /**
+     * Check if path looks valid and doesn't contain suspecious patterns.
+
+     * The path must meet the following criteria:
+     *
+     * - It must be a string
+     * - No NUL character
+     * - No control characters between 0-20
+     * - No phar stream wrapper
+     * - No php stream wrapper
+     * - No glob stream wrapper
+     * - Not empty path
+     *
+     * @throws \Exception  In case the path doesn't meet all criteria
+     */
+    public static function checkPath($path)
+    {
+        if (gettype($path) !== 'string') {
+            throw new \Exception('File path must be string');
+        }
+        if (strpos($path, chr(0)) !== false) {
+            throw new \Exception('NUL character is not allowed in file path!');
+        }
+        if (preg_match('#[\x{0}-\x{1f}]#', $path)) {
+            // prevents line feed, new line, tab, charater return, tab, ets.
+            throw new \Exception('Control characters #0-#20 not allowed in file path!');
+        }
+        // Prevent phar stream wrappers (security threat)
+        if (preg_match('#^phar://#', $path)) {
+            throw new \Exception('phar stream wrappers are not allowed in file path');
+        }
+        if (preg_match('#^(php|glob)://#', $path)) {
+            throw new \Exception('php and glob stream wrappers are not allowed in file path');
+        }
+        if (empty($path)) {
+            throw new \Exception('File path is empty!');
+        }
+    }
+
+    /**
+     * Check if path points to a regular file (and doesnt match suspecious patterns).
+     *
+     * @throws \Exception  In case the path doesn't point to a regular file or matches suspecious patterns
+     */
+    public static function checkFilePathIsRegularFile($path)
+    {
+        self::checkPath($path);
+
+        if (!FileExists::fileExists($path)) {
+            throw new \Exception('File does not exist');
+        }
+        if (@is_dir($path)) {
+            throw new \Exception('Expected a regular file, not a dir');
+        }
+    }
+}