gecko-dev/dom/base/ViewportMetaData.cpp

116 строки
3.5 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 "nsContentUtils.h"
#include "nsCRT.h"
#include "ViewportMetaData.h"
using namespace mozilla;
using namespace mozilla::dom;
/*
* Helper function for ViewportMetaData::ProcessViewportInfo.
*
* Handles a single key=value pair. If it corresponds to a valid viewport
* attribute, add it to the document header data. No validation is done on the
* value itself (this is done at display time).
*/
static void ProcessViewportToken(ViewportMetaData& aData,
const nsAString& token) {
/* Iterators. */
nsAString::const_iterator tip, tail, end;
token.BeginReading(tip);
tail = tip;
token.EndReading(end);
/* Move tip to the '='. */
while ((tip != end) && (*tip != '=')) {
++tip;
}
/* If we didn't find an '=', punt. */
if (tip == end) {
return;
}
/* Extract the key and value. */
const nsAString& key = nsContentUtils::TrimWhitespace<nsCRT::IsAsciiSpace>(
Substring(tail, tip), true);
const nsAString& value = nsContentUtils::TrimWhitespace<nsCRT::IsAsciiSpace>(
Substring(++tip, end), true);
/* Check for known keys. If we find a match, insert the appropriate
* information into the document header. */
RefPtr<nsAtom> key_atom = NS_Atomize(key);
if (key_atom == nsGkAtoms::height) {
aData.mHeight.Assign(value);
} else if (key_atom == nsGkAtoms::width) {
aData.mWidth.Assign(value);
} else if (key_atom == nsGkAtoms::initial_scale) {
aData.mInitialScale.Assign(value);
} else if (key_atom == nsGkAtoms::minimum_scale) {
aData.mMinimumScale.Assign(value);
} else if (key_atom == nsGkAtoms::maximum_scale) {
aData.mMaximumScale.Assign(value);
} else if (key_atom == nsGkAtoms::user_scalable) {
aData.mUserScalable.Assign(value);
} else if (key_atom == nsGkAtoms::viewport_fit) {
aData.mViewportFit.Assign(value);
}
}
#define IS_SEPARATOR(c) \
(((c) == '=') || ((c) == ',') || ((c) == ';') || ((c) == '\t') || \
((c) == '\n') || ((c) == '\r'))
ViewportMetaData::ViewportMetaData(const nsAString& aViewportInfo) {
/* Iterators. */
nsAString::const_iterator tip, tail, end;
aViewportInfo.BeginReading(tip);
tail = tip;
aViewportInfo.EndReading(end);
/* Read the tip to the first non-separator character. */
while ((tip != end) && (IS_SEPARATOR(*tip) || nsCRT::IsAsciiSpace(*tip))) {
++tip;
}
/* Read through and find tokens separated by separators. */
while (tip != end) {
/* Synchronize tip and tail. */
tail = tip;
/* Advance tip past non-separator characters. */
while ((tip != end) && !IS_SEPARATOR(*tip)) {
++tip;
}
/* Allow white spaces that surround the '=' character */
if ((tip != end) && (*tip == '=')) {
++tip;
while ((tip != end) && nsCRT::IsAsciiSpace(*tip)) {
++tip;
}
while ((tip != end) &&
!(IS_SEPARATOR(*tip) || nsCRT::IsAsciiSpace(*tip))) {
++tip;
}
}
/* Our token consists of the characters between tail and tip. */
ProcessViewportToken(*this, Substring(tail, tip));
/* Skip separators. */
while ((tip != end) && (IS_SEPARATOR(*tip) || nsCRT::IsAsciiSpace(*tip))) {
++tip;
}
}
}
#undef IS_SEPARATOR