CAssetManager

public function getBasePath()
{
    if($this->_basePath===null)
    {
        $request=Yii::app()->getRequest();
        $this->setBasePath(dirname($request->getScriptFile()).DIRECTORY_SEPARATOR.self::DEFAULT_BASEPATH);
    }
    return $this->_basePath;
}

public function getBaseUrl()
{
    if($this->_baseUrl===null)
    {
        $request=Yii::app()->getRequest();
        $this->setBaseUrl($request->getBaseUrl().'/'.self::DEFAULT_BASEPATH);
    }
    return $this->_baseUrl;
}

public function getPublishedPath($path,$hashByName=false)
{
    if(($path=realpath($path))!==false)
    {
        $base=$this->getBasePath().DIRECTORY_SEPARATOR;
        if(is_file($path))
            return $base . $this->hash($hashByName ? basename($path) : dirname($path).filemtime($path)) . DIRECTORY_SEPARATOR . basename($path);
        else
            return $base . $this->hash($hashByName ? basename($path) : $path.filemtime($path));
    }
    else
        return false;
}

public function getPublishedUrl($path,$hashByName=false)
{
    if(isset($this->_published[$path]))
        return $this->_published[$path];
    if(($path=realpath($path))!==false)
    {
        if(is_file($path))
            return $this->getBaseUrl().'/'.$this->hash($hashByName ? basename($path) : dirname($path).filemtime($path)).'/'.basename($path);
        else
            return $this->getBaseUrl().'/'.$this->hash($hashByName ? basename($path) : $path.filemtime($path));
    }
    else
        return false;
}

protected function hash($path)
{
    return sprintf('%x',crc32($path.Yii::getVersion()));
}

public function publish($path,$hashByName=false,$level=-1,$forceCopy=false)
{
    if(isset($this->_published[$path]))
        return $this->_published[$path];
    else if(($src=realpath($path))!==false)
    {
        if(is_file($src))
        {
            $dir=$this->hash($hashByName ? basename($src) : dirname($src).filemtime($src));
            $fileName=basename($src);
            $dstDir=$this->getBasePath().DIRECTORY_SEPARATOR.$dir;
            $dstFile=$dstDir.DIRECTORY_SEPARATOR.$fileName;

            if($this->linkAssets)
            {
                if(!is_file($dstFile))
                {
                    if(!is_dir($dstDir))
                    {
                        mkdir($dstDir);
                        @chmod($dstDir, $this->newDirMode);
                    }
                    symlink($src,$dstFile);
                }
            }
            else if(@filemtime($dstFile)<@filemtime($src))
            {
                if(!is_dir($dstDir))
                {
                    mkdir($dstDir);
                    @chmod($dstDir, $this->newDirMode);
                }
                copy($src,$dstFile);
                @chmod($dstFile, $this->newFileMode);
            }

            return $this->_published[$path]=$this->getBaseUrl()."/$dir/$fileName";
        }
        else if(is_dir($src))
        {
            $dir=$this->hash($hashByName ? basename($src) : $src.filemtime($src));
            $dstDir=$this->getBasePath().DIRECTORY_SEPARATOR.$dir;

            if($this->linkAssets)
            {
                if(!is_dir($dstDir))
                    symlink($src,$dstDir);
            }
            else if(!is_dir($dstDir) || $forceCopy)
            {
                CFileHelper::copyDirectory($src,$dstDir,array(
                    'exclude'=>$this->excludeFiles,
                    'level'=>$level,
                    'newDirMode'=>$this->newDirMode,
                    'newFileMode'=>$this->newFileMode,
                ));
            }

            return $this->_published[$path]=$this->getBaseUrl().'/'.$dir;
        }
    }
    throw new CException(Yii::t('yii','The asset "{asset}" to be published does not exist.',
        array('{asset}'=>$path)));
}

public function setBasePath($value)
{
    if(($basePath=realpath($value))!==false && is_dir($basePath) && is_writable($basePath))
        $this->_basePath=$basePath;
    else
        throw new CException(Yii::t('yii','CAssetManager.basePath "{path}" is invalid. Please make sure the directory exists and is writable by the Web server process.',
            array('{path}'=>$value)));
}

public function setBaseUrl($value)
{
    $this->_baseUrl=rtrim($value,'/');
}