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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "nsHTMLTags.h"
#include "nsCRT.h"
#include "nsElementTable.h"
#include "nsReadableUtils.h"
#include "nsString.h"
#include "nsUnicharUtils.h"
#include "mozilla/HashFunctions.h"
#include <algorithm>
using namespace mozilla;
// static array of unicode tag names
#define HTML_TAG(_tag, _classname, _interfacename) (u"" #_tag),
#define HTML_OTHER(_tag)
const char16_t* const nsHTMLTags::sTagNames[] = {
#include "nsHTMLTagList.h"
};
#undef HTML_TAG
#undef HTML_OTHER
int32_t nsHTMLTags::gTableRefCount;
nsHTMLTags::TagStringHash* nsHTMLTags::gTagTable;
nsHTMLTags::TagAtomHash* nsHTMLTags::gTagAtomTable;
#define NS_HTMLTAG_NAME_MAX_LENGTH 10
// static
nsresult nsHTMLTags::AddRefTable(void) {
if (gTableRefCount++ == 0) {
NS_ASSERTION(!gTagTable && !gTagAtomTable, "pre existing hash!");
gTagTable = new TagStringHash(64);
gTagAtomTable = new TagAtomHash(64);
// Fill in gTagTable with the above static char16_t strings as
// keys and the value of the corresponding enum as the value in
// the table.
for (int32_t i = 0; i < NS_HTML_TAG_MAX; ++i) {
const char16_t* tagName = sTagNames[i];
const nsHTMLTag tagValue = static_cast<nsHTMLTag>(i + 1);
// We use AssignLiteral here to avoid a string copy. This is okay
// because this is truly static data.
nsString tmp;
tmp.AssignLiteral(tagName, nsString::char_traits::length(tagName));
gTagTable->InsertOrUpdate(tmp, tagValue);
// All the HTML tag names are static atoms within nsGkAtoms, and they are
// registered before this code is reached.
nsStaticAtom* atom = NS_GetStaticAtom(tmp);
MOZ_ASSERT(atom);
gTagAtomTable->InsertOrUpdate(atom, tagValue);
}
#ifdef DEBUG
// Check all tagNames are lowercase, and that NS_HTMLTAG_NAME_MAX_LENGTH is
// correct.
uint32_t maxTagNameLength = 0;
for (int i = 0; i < NS_HTML_TAG_MAX; ++i) {
const char16_t* tagName = sTagNames[i];
nsAutoString lowerTagName(tagName);
ToLowerCase(lowerTagName);
MOZ_ASSERT(lowerTagName.Equals(tagName));
maxTagNameLength = std::max(NS_strlen(tagName), maxTagNameLength);
}
MOZ_ASSERT(maxTagNameLength == NS_HTMLTAG_NAME_MAX_LENGTH);
CheckElementTable();
TestTagTable();
#endif
}
return NS_OK;
}
// static
void nsHTMLTags::ReleaseTable(void) {
if (0 == --gTableRefCount) {
delete gTagTable;
delete gTagAtomTable;
gTagTable = nullptr;
gTagAtomTable = nullptr;
}
}
// static
nsHTMLTag nsHTMLTags::StringTagToId(const nsAString& aTagName) {
uint32_t length = aTagName.Length();
if (length > NS_HTMLTAG_NAME_MAX_LENGTH) {
return eHTMLTag_userdefined;
}
// Setup a stack allocated string buffer with the appropriate length.
nsAutoString lowerCase;
lowerCase.SetLength(length);
// Operate on the raw buffers to avoid bounds checks.
auto src = aTagName.BeginReading();
auto dst = lowerCase.BeginWriting();
// Fast lowercasing-while-copying of ASCII characters into a
// nsString buffer.
for (uint32_t i = 0; i < length; i++) {
char16_t c = src[i];
if (c <= 'Z' && c >= 'A') {
c |= 0x20; // Lowercase the ASCII character.
}
dst[i] = c; // Copy ASCII character.
}
return CaseSensitiveStringTagToId(lowerCase);
}
#ifdef DEBUG
void nsHTMLTags::TestTagTable() {
const char16_t* tag;
nsHTMLTag id;
RefPtr<nsAtom> atom;
nsHTMLTags::AddRefTable();
// Make sure we can find everything we are supposed to
for (int i = 0; i < NS_HTML_TAG_MAX; ++i) {
tag = sTagNames[i];
const nsAString& tagString = nsDependentString(tag);
id = StringTagToId(tagString);
NS_ASSERTION(id != eHTMLTag_userdefined, "can't find tag id");
nsAutoString uname(tagString);
ToUpperCase(uname);
NS_ASSERTION(id == StringTagToId(uname), "wrong id");
NS_ASSERTION(id == CaseSensitiveStringTagToId(tagString), "wrong id");
atom = NS_Atomize(tag);
NS_ASSERTION(id == CaseSensitiveAtomTagToId(atom), "wrong id");
}
// Make sure we don't find things that aren't there
id = StringTagToId(u"@"_ns);
NS_ASSERTION(id == eHTMLTag_userdefined, "found @");
id = StringTagToId(u"zzzzz"_ns);
NS_ASSERTION(id == eHTMLTag_userdefined, "found zzzzz");
atom = NS_Atomize("@");
id = CaseSensitiveAtomTagToId(atom);
NS_ASSERTION(id == eHTMLTag_userdefined, "found @");
atom = NS_Atomize("zzzzz");
id = CaseSensitiveAtomTagToId(atom);
NS_ASSERTION(id == eHTMLTag_userdefined, "found zzzzz");
ReleaseTable();
}
#endif // DEBUG