Evaluates a string of PHP code.
This is a wrapper around PHP's eval(). It uses output buffering to capture both returned and printed text. Unlike eval(), we require code to be surrounded by <?php ?> tags; in other words, we evaluate the code as if it were a stand-alone PHP file.
Using this wrapper also ensures that the PHP code which is evaluated can not overwrite any variables in the calling code, unlike a regular eval() call.
This function is also used as an implementation of callback_filter_process().
$code: The code to evaluate.
A string containing the printed output of the code, followed by the returned output of the code.
function php_eval($code) {
global $theme_path, $theme_info, $conf;
// Store current theme path.
$old_theme_path = $theme_path;
// Restore theme_path to the theme, as long as php_eval() executes,
// so code evaluated will not see the caller module as the current theme.
// If theme info is not initialized get the path from theme_default.
if (!isset($theme_info)) {
$theme_path = drupal_get_path('theme', $conf['theme_default']);
}
else {
$theme_path = dirname($theme_info->filename);
}
ob_start();
print eval('?>' . $code);
$output = ob_get_contents();
ob_end_clean();
// Recover original theme path.
$theme_path = $old_theme_path;
return $output;
}