$minimized
$minimized
Tells us whether or not an HTML attribute is minimized.
Has no meaning in other contexts.
Validates the HTML attribute style, otherwise known as CSS.
parseCDATA(mixed $string) : mixed
Convenience method that parses a string as if it were CDATA.
This method process a string in the manner specified at http://www.w3.org/TR/html4/types.html#h-6.2 by removing leading and trailing whitespace, ignoring line feeds, and replacing carriage returns and tabs with spaces. While most useful for HTML attributes specified as CDATA, it can also be applied to most CSS values.
| mixed | $string |
<?php
/**
* Validates the HTML attribute style, otherwise known as CSS.
* @note We don't implement the whole CSS specification, so it might be
* difficult to reuse this component in the context of validating
* actual stylesheet declarations.
* @note If we were really serious about validating the CSS, we would
* tokenize the styles and then parse the tokens. Obviously, we
* are not doing that. Doing that could seriously harm performance,
* but would make these components a lot more viable for a CSS
* filtering solution.
*/
class HTMLPurifier_AttrDef_CSS extends HTMLPurifier_AttrDef
{
/**
* @param string $css
* @param HTMLPurifier_Config $config
* @param HTMLPurifier_Context $context
* @return bool|string
*/
public function validate($css, $config, $context)
{
$css = $this->parseCDATA($css);
$definition = $config->getCSSDefinition();
$allow_duplicates = $config->get("CSS.AllowDuplicates");
// According to the CSS2.1 spec, the places where a
// non-delimiting semicolon can appear are in strings
// escape sequences. So here is some dumb hack to
// handle quotes.
$len = strlen($css);
$accum = "";
$declarations = array();
$quoted = false;
for ($i = 0; $i < $len; $i++) {
$c = strcspn($css, ";'\"", $i);
$accum .= substr($css, $i, $c);
$i += $c;
if ($i == $len) break;
$d = $css[$i];
if ($quoted) {
$accum .= $d;
if ($d == $quoted) {
$quoted = false;
}
} else {
if ($d == ";") {
$declarations[] = $accum;
$accum = "";
} else {
$accum .= $d;
$quoted = $d;
}
}
}
if ($accum != "") $declarations[] = $accum;
$propvalues = array();
$new_declarations = '';
/**
* Name of the current CSS property being validated.
*/
$property = false;
$context->register('CurrentCSSProperty', $property);
foreach ($declarations as $declaration) {
if (!$declaration) {
continue;
}
if (!strpos($declaration, ':')) {
continue;
}
list($property, $value) = explode(':', $declaration, 2);
$property = trim($property);
$value = trim($value);
$ok = false;
do {
if (isset($definition->info[$property])) {
$ok = true;
break;
}
if (ctype_lower($property)) {
break;
}
$property = strtolower($property);
if (isset($definition->info[$property])) {
$ok = true;
break;
}
} while (0);
if (!$ok) {
continue;
}
// inefficient call, since the validator will do this again
if (strtolower(trim($value)) !== 'inherit') {
// inherit works for everything (but only on the base property)
$result = $definition->info[$property]->validate(
$value,
$config,
$context
);
} else {
$result = 'inherit';
}
if ($result === false) {
continue;
}
if ($allow_duplicates) {
$new_declarations .= "$property:$result;";
} else {
$propvalues[$property] = $result;
}
}
$context->destroy('CurrentCSSProperty');
// procedure does not write the new CSS simultaneously, so it's
// slightly inefficient, but it's the only way of getting rid of
// duplicates. Perhaps config to optimize it, but not now.
foreach ($propvalues as $prop => $value) {
$new_declarations .= "$prop:$value;";
}
return $new_declarations ? $new_declarations : false;
}
}
// vim: et sw=4 sts=4