MISP/app/Lib/Tools/FileAccessTool.php

<?php

class FileAccessTool
{
    private $__fileErrorMsgPrefix = 'An error has occured while attempting to ';

    public function createTempFile($dir, $prefix = 'MISP')
    {
        $tempFile = tempnam($dir, $prefix);
        $this->__checkForFalse($tempFile, 'create a temporary file in path "' . $dir);
        return $tempFile;
    }

    public function readFromFile($file, $fileSize = -1)
    {
        $this->__checkForFalse($file, 'create file "' . $file);
        $fileHandle = fopen($file, 'rb');
        $this->__checkForFalse($fileHandle, 'access file "' . $file);
        if ($fileSize === -1) {
            $fileSize = filesize($file);
            $this->__checkForFalse($fileHandle, 'get filesize from file "' . $file);
        }
        $readResult = fread($fileHandle, $fileSize);
        $this->__checkForFalse($fileHandle, 'read from file "' . $file);
        fclose($fileHandle);
        return $readResult;
    }

    public function writeToFile($file, $content)
    {
        $this->__checkForFalse($file, 'create file "' . $file);
        $fileHandle = fopen($file, 'wb');
        $this->__checkForFalse($fileHandle, 'access file "' . $file);
        $writeResult = fwrite($fileHandle, $content);
        $this->__checkForFalse($writeResult, 'write to file "' . $file);
        fclose($fileHandle);
        return $file;
    }

    private function __checkForFalse($result, $errorMsgPart)
    {
        if ($result === false) {
            throw new MethodNotAllowedException($this->__fileErrorMsgPrefix . $errorMsgPart . '".');
        }
    }

    public function deleteFile($file)
    {
        unlink($file);
        return true;
    }
}