mirror of
https://github.com/ezyang/htmlpurifier.git
synced 2024-09-19 18:55:19 +00:00
Profusely comment FixNesting.
git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@183 48356398-32a2-884e-a903-53898d9a118a
This commit is contained in:
Edward Z. Yang
parent
7e2693fdea
commit
9cec089f97
@ -42,31 +42,53 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
|
||||
function execute($tokens) {
|
||||
|
||||
// insert implicit "parent" node, will be removed at end
|
||||
//####################################################################//
|
||||
// Pre-processing
|
||||
|
||||
// insert implicit "parent" node, will be removed at end.
|
||||
// ! we might want to move this to configuration
|
||||
// DEFINITION CALL
|
||||
$parent_name = $this->definition->info_parent;
|
||||
array_unshift($tokens, new HTMLPurifier_Token_Start($parent_name));
|
||||
$tokens[] = new HTMLPurifier_Token_End($parent_name);
|
||||
|
||||
//####################################################################//
|
||||
// Loop initialization
|
||||
|
||||
// stack that contains the indexes of all parents,
|
||||
// $stack[count($stack)-1] being the current parent
|
||||
$stack = array();
|
||||
|
||||
// stack that contains all elements that are excluded
|
||||
// same structure as $stack, but it is only populated when an element
|
||||
// with exclusions is processed, i.e. there won't be empty exclusions.
|
||||
$exclude_stack = array();
|
||||
|
||||
//####################################################################//
|
||||
// Loop
|
||||
|
||||
// iterate through all start nodes. Determining the start node
|
||||
// is complicated so it has been omitted from the loop construct
|
||||
for ($i = 0, $size = count($tokens) ; $i < $size; ) {
|
||||
|
||||
//################################################################//
|
||||
// Gather information on children
|
||||
|
||||
// child token accumulator
|
||||
$child_tokens = array();
|
||||
|
||||
// scroll to the end of this node, and report number
|
||||
// scroll to the end of this node, report number, and collect
|
||||
// all children
|
||||
for ($j = $i, $depth = 0; ; $j++) {
|
||||
if ($tokens[$j]->type == 'start') {
|
||||
$depth++;
|
||||
// skip token assignment on first iteration
|
||||
// skip token assignment on first iteration, this is the
|
||||
// token we currently are on
|
||||
if ($depth == 1) continue;
|
||||
} elseif ($tokens[$j]->type == 'end') {
|
||||
$depth--;
|
||||
// skip token assignment on last iteration
|
||||
// skip token assignment on last iteration, this is the
|
||||
// end token of the token we're currently on
|
||||
if ($depth == 0) break;
|
||||
}
|
||||
$child_tokens[] = $tokens[$j];
|
||||
@ -75,12 +97,16 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
// $i is index of start token
|
||||
// $j is index of end token
|
||||
|
||||
//################################################################//
|
||||
// Gather information on parent
|
||||
|
||||
// calculate parent information
|
||||
if ($count = count($stack)) {
|
||||
$parent_index = $stack[$count-1];
|
||||
$parent_name = $tokens[$parent_index]->name;
|
||||
$parent_def = $this->definition->info[$parent_name];
|
||||
} else {
|
||||
// unknown info, it won't be used anyway
|
||||
$parent_index = $parent_name = $parent_def = null;
|
||||
}
|
||||
|
||||
@ -88,26 +114,36 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
if (isset($parent_def)) {
|
||||
$context = $parent_def->type;
|
||||
} else {
|
||||
// generally found in specialized elements like UL
|
||||
$context = 'unknown';
|
||||
}
|
||||
|
||||
// determine whether or not element is excluded
|
||||
//################################################################//
|
||||
// Determine whether element is explicitly excluded SGML-style
|
||||
|
||||
// determine whether or not element is excluded by checking all
|
||||
// parent exclusions. The array should not be very large, two
|
||||
// elements at most.
|
||||
$excluded = false;
|
||||
if (!empty($exclude_stack)) {
|
||||
foreach ($exclude_stack as $lookup) {
|
||||
if (isset($lookup[$tokens[$i]->name])) {
|
||||
$excluded = true;
|
||||
// no need to continue processing
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
//################################################################//
|
||||
// Perform child validation
|
||||
|
||||
if ($excluded) {
|
||||
// there is an exclusion, remove the entire node
|
||||
$result = false;
|
||||
} else {
|
||||
// DEFINITION CALL
|
||||
$def = $this->definition->info[$tokens[$i]->name];
|
||||
|
||||
$child_def = $def->child;
|
||||
|
||||
// have DTD child def validate children
|
||||
@ -117,9 +153,12 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
$excludes = $def->excludes;
|
||||
}
|
||||
|
||||
// process result
|
||||
// $result is now a bool or array
|
||||
|
||||
//################################################################//
|
||||
// Process result by interpreting $result
|
||||
|
||||
if ($result === true) {
|
||||
|
||||
// leave the node as is
|
||||
|
||||
// register start token as a parental node start
|
||||
@ -132,13 +171,15 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
$i++;
|
||||
|
||||
} elseif($result === false) {
|
||||
// remove entire node
|
||||
|
||||
// calculate length of inner tokens and current tokens
|
||||
$length = $j - $i + 1;
|
||||
|
||||
// remove entire node
|
||||
// perform removal
|
||||
array_splice($tokens, $i, $length);
|
||||
|
||||
// change size
|
||||
// update size
|
||||
$size -= $length;
|
||||
|
||||
// there is no start token to register,
|
||||
@ -150,14 +191,19 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
$i = $parent_index;
|
||||
}
|
||||
|
||||
} else {
|
||||
// PROJECTED OPTIMIZATION: Process all children elements before
|
||||
// reprocessing parent node.
|
||||
|
||||
} else {
|
||||
// replace node with $result
|
||||
|
||||
// calculate length of inner tokens
|
||||
$length = $j - $i - 1;
|
||||
|
||||
// replace node with $result
|
||||
// perform replacement
|
||||
array_splice($tokens, $i + 1, $length, $result);
|
||||
|
||||
// change size
|
||||
// update size
|
||||
$size -= $length;
|
||||
$size += count($result);
|
||||
|
||||
@ -172,6 +218,9 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
|
||||
}
|
||||
|
||||
//################################################################//
|
||||
// Scroll to next start node
|
||||
|
||||
// We assume, at this point, that $i is the index of the token
|
||||
// that is the first possible new start point for a node.
|
||||
|
||||
@ -192,10 +241,16 @@ class HTMLPurifier_Strategy_FixNesting extends HTMLPurifier_Strategy
|
||||
|
||||
}
|
||||
|
||||
// remove implicit divs
|
||||
//####################################################################//
|
||||
// Post-processing
|
||||
|
||||
// remove implicit parent tokens at the beginning and end
|
||||
array_shift($tokens);
|
||||
array_pop($tokens);
|
||||
|
||||
//####################################################################//
|
||||
// Return
|
||||
|
||||
return $tokens;
|
||||
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user