b083a233d8
This patch adds the CharacterData subclass of Node, which is now the parent class of Text and a new Comment class. A Comment node is one of these in HTML: <!--hello friends--> Since these occur somewhat frequently on the web, we need to be able to parse them. This patch also adds a child rejection mechanism to the DOM tree. Nodes can now override is_child_allowed(Node) and return false if they don't want a particular Node to become a child of theirs. This is used to prevent Document from taking on unwanted children.
325 lines
9.6 KiB
C++
325 lines
9.6 KiB
C++
#include <AK/Function.h>
|
|
#include <AK/NonnullRefPtrVector.h>
|
|
#include <AK/StringBuilder.h>
|
|
#include <LibHTML/DOM/Comment.h>
|
|
#include <LibHTML/DOM/DocumentType.h>
|
|
#include <LibHTML/DOM/Element.h>
|
|
#include <LibHTML/DOM/ElementFactory.h>
|
|
#include <LibHTML/DOM/Text.h>
|
|
#include <LibHTML/Parser/HTMLParser.h>
|
|
#include <ctype.h>
|
|
#include <stdio.h>
|
|
|
|
static bool is_valid_in_attribute_name(char ch)
|
|
{
|
|
return isalnum(ch) || ch == '_' || ch == '-';
|
|
}
|
|
|
|
static bool is_self_closing_tag(const StringView& tag_name)
|
|
{
|
|
return tag_name == "area"
|
|
|| tag_name == "base"
|
|
|| tag_name == "br"
|
|
|| tag_name == "col"
|
|
|| tag_name == "embed"
|
|
|| tag_name == "hr"
|
|
|| tag_name == "img"
|
|
|| tag_name == "input"
|
|
|| tag_name == "link"
|
|
|| tag_name == "meta"
|
|
|| tag_name == "param"
|
|
|| tag_name == "source"
|
|
|| tag_name == "track"
|
|
|| tag_name == "wbr";
|
|
}
|
|
|
|
NonnullRefPtr<Document> parse_html(const StringView& html, const URL& url)
|
|
{
|
|
NonnullRefPtrVector<ParentNode> node_stack;
|
|
|
|
auto document = adopt(*new Document);
|
|
document->set_url(url);
|
|
node_stack.append(document);
|
|
|
|
enum class State {
|
|
Free = 0,
|
|
BeforeTagName,
|
|
InTagName,
|
|
InDoctype,
|
|
InComment,
|
|
InAttributeList,
|
|
InAttributeName,
|
|
BeforeAttributeValue,
|
|
InAttributeValueNoQuote,
|
|
InAttributeValueSingleQuote,
|
|
InAttributeValueDoubleQuote,
|
|
};
|
|
|
|
auto state = State::Free;
|
|
|
|
StringBuilder text_buffer;
|
|
|
|
Vector<char, 32> tag_name_buffer;
|
|
|
|
Vector<Attribute> attributes;
|
|
Vector<char, 256> attribute_name_buffer;
|
|
Vector<char, 256> attribute_value_buffer;
|
|
|
|
bool is_slash_tag = false;
|
|
bool is_exclamation_tag = false;
|
|
|
|
auto move_to_state = [&](State new_state) {
|
|
if (new_state == State::BeforeTagName) {
|
|
is_slash_tag = false;
|
|
is_exclamation_tag = false;
|
|
tag_name_buffer.clear();
|
|
attributes.clear();
|
|
}
|
|
if (new_state == State::InAttributeName)
|
|
attribute_name_buffer.clear();
|
|
if (new_state == State::BeforeAttributeValue)
|
|
attribute_value_buffer.clear();
|
|
if (state == State::Free && !text_buffer.string_view().is_empty()) {
|
|
auto text_node = adopt(*new Text(document, text_buffer.to_string()));
|
|
node_stack.last().append_child(text_node, false);
|
|
}
|
|
state = new_state;
|
|
text_buffer.clear();
|
|
};
|
|
|
|
auto close_tag = [&] {
|
|
if (node_stack.size() > 1)
|
|
node_stack.take_last();
|
|
};
|
|
|
|
auto open_tag = [&] {
|
|
auto new_element = create_element(document, String::copy(tag_name_buffer));
|
|
tag_name_buffer.clear();
|
|
new_element->set_attributes(move(attributes));
|
|
node_stack.append(new_element);
|
|
if (node_stack.size() != 1)
|
|
node_stack[node_stack.size() - 2].append_child(new_element, false);
|
|
|
|
if (is_self_closing_tag(new_element->tag_name()))
|
|
close_tag();
|
|
};
|
|
|
|
auto commit_doctype = [&] {
|
|
node_stack.last().append_child(adopt(*new DocumentType(document)), false);
|
|
};
|
|
|
|
auto commit_comment = [&] {
|
|
node_stack.last().append_child(adopt(*new Comment(document, text_buffer.to_string())), false);
|
|
};
|
|
|
|
auto commit_tag = [&] {
|
|
if (is_slash_tag)
|
|
close_tag();
|
|
else
|
|
open_tag();
|
|
};
|
|
|
|
auto commit_attribute = [&] {
|
|
attributes.append({ String::copy(attribute_name_buffer), String::copy(attribute_value_buffer) });
|
|
};
|
|
|
|
for (int i = 0; i < html.length(); ++i) {
|
|
auto peek = [&](int offset) -> char {
|
|
if (i + offset >= html.length())
|
|
return '\0';
|
|
return html[i + offset];
|
|
};
|
|
char ch = html[i];
|
|
switch (state) {
|
|
case State::Free:
|
|
if (ch == '<') {
|
|
is_slash_tag = false;
|
|
move_to_state(State::BeforeTagName);
|
|
break;
|
|
}
|
|
if (ch != '&') {
|
|
text_buffer.append(ch);
|
|
} else {
|
|
struct Escape {
|
|
const char* code;
|
|
const char* value;
|
|
};
|
|
static Escape escapes[] = {
|
|
{ "<", "<" },
|
|
{ ">", ">" },
|
|
{ "&", "&" }
|
|
};
|
|
auto rest_of_html = html.substring_view(i, html.length() - i);
|
|
bool found = false;
|
|
for (auto& escape : escapes) {
|
|
if (rest_of_html.starts_with(escape.code)) {
|
|
text_buffer.append(escape.value);
|
|
found = true;
|
|
i += strlen(escape.code) - 1;
|
|
break;
|
|
}
|
|
}
|
|
if (!found)
|
|
dbg() << "Unhandled escape sequence";
|
|
}
|
|
break;
|
|
case State::BeforeTagName:
|
|
if (ch == '/') {
|
|
is_slash_tag = true;
|
|
break;
|
|
}
|
|
if (ch == '!') {
|
|
if (peek(1) == 'D'
|
|
&& peek(2) == 'O'
|
|
&& peek(3) == 'C'
|
|
&& peek(4) == 'T'
|
|
&& peek(5) == 'Y'
|
|
&& peek(6) == 'P'
|
|
&& peek(7) == 'E') {
|
|
i += 7;
|
|
move_to_state(State::InDoctype);
|
|
break;
|
|
}
|
|
if (peek(1) == '-' && peek(2) == '-') {
|
|
i += 2;
|
|
move_to_state(State::InComment);
|
|
break;
|
|
}
|
|
break;
|
|
}
|
|
if (ch == '>') {
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
if (!isalpha(ch))
|
|
break;
|
|
move_to_state(State::InTagName);
|
|
[[fallthrough]];
|
|
case State::InTagName:
|
|
if (isspace(ch)) {
|
|
move_to_state(State::InAttributeList);
|
|
break;
|
|
}
|
|
if (ch == '>') {
|
|
commit_tag();
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
tag_name_buffer.append(ch);
|
|
break;
|
|
case State::InDoctype:
|
|
if (ch == '>') {
|
|
commit_doctype();
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
break;
|
|
case State::InComment:
|
|
if (ch == '-' && peek(1) == '-' && peek(2) == '>') {
|
|
commit_comment();
|
|
i += 2;
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
text_buffer.append(ch);
|
|
break;
|
|
case State::InAttributeList:
|
|
if (ch == '>') {
|
|
commit_tag();
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
if (!isalpha(ch))
|
|
break;
|
|
move_to_state(State::InAttributeName);
|
|
[[fallthrough]];
|
|
case State::InAttributeName:
|
|
if (is_valid_in_attribute_name(ch)) {
|
|
attribute_name_buffer.append(ch);
|
|
break;
|
|
}
|
|
if (isspace(ch)) {
|
|
commit_attribute();
|
|
break;
|
|
}
|
|
|
|
if (ch == '>') {
|
|
commit_tag();
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
|
|
if (ch == '=') {
|
|
move_to_state(State::BeforeAttributeValue);
|
|
break;
|
|
}
|
|
break;
|
|
case State::BeforeAttributeValue:
|
|
if (ch == '\'') {
|
|
move_to_state(State::InAttributeValueSingleQuote);
|
|
break;
|
|
}
|
|
if (ch == '"') {
|
|
move_to_state(State::InAttributeValueDoubleQuote);
|
|
break;
|
|
}
|
|
if (ch == '>') {
|
|
commit_tag();
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
if (isspace(ch)) {
|
|
commit_attribute();
|
|
move_to_state(State::InAttributeList);
|
|
break;
|
|
}
|
|
break;
|
|
case State::InAttributeValueSingleQuote:
|
|
if (ch == '\'') {
|
|
commit_attribute();
|
|
move_to_state(State::InAttributeList);
|
|
break;
|
|
}
|
|
attribute_value_buffer.append(ch);
|
|
break;
|
|
case State::InAttributeValueDoubleQuote:
|
|
if (ch == '"') {
|
|
commit_attribute();
|
|
move_to_state(State::InAttributeList);
|
|
break;
|
|
}
|
|
attribute_value_buffer.append(ch);
|
|
break;
|
|
case State::InAttributeValueNoQuote:
|
|
if (isspace(ch)) {
|
|
commit_attribute();
|
|
move_to_state(State::InAttributeList);
|
|
break;
|
|
}
|
|
if (ch == '>') {
|
|
commit_tag();
|
|
move_to_state(State::Free);
|
|
break;
|
|
}
|
|
attribute_value_buffer.append(ch);
|
|
break;
|
|
default:
|
|
fprintf(stderr, "Unhandled state %d\n", (int)state);
|
|
ASSERT_NOT_REACHED();
|
|
}
|
|
}
|
|
|
|
Function<void(Node&)> fire_insertion_callbacks = [&](Node& node) {
|
|
for (auto* child = node.first_child(); child; child = child->next_sibling()) {
|
|
fire_insertion_callbacks(*child);
|
|
}
|
|
if (node.parent())
|
|
node.inserted_into(*node.parent());
|
|
};
|
|
|
|
fire_insertion_callbacks(*document);
|
|
|
|
document->fixup();
|
|
|
|
return document;
|
|
}
|