uBlock/js/contentscript-start.js

199 lines
6.3 KiB
JavaScript

/*******************************************************************************
µBlock - a Chromium browser extension to block requests.
Copyright (C) 2014 Raymond Hill
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see {http://www.gnu.org/licenses/}.
Home: https://github.com/gorhill/uBlock
*/
/* jshint multistr: true */
/* global chrome */
// Injected into content pages
/******************************************************************************/
// OK, I keep changing my mind whether a closure should be used or not. This
// will be the rule: if there are any variables directly accessed on a regular
// basis, use a closure so that they are cached. Otherwise I don't think the
// overhead of a closure is worth it. That's my understanding.
(function() {
/******************************************************************************/
/******************************************************************************/
// https://github.com/gorhill/httpswitchboard/issues/345
var messaging = (function(name){
var port = null;
var dangling = false;
var requestId = 1;
var requestIdToCallbackMap = {};
var listenCallback = null;
var onPortMessage = function(details) {
if ( typeof details.id !== 'number' ) {
return;
}
// Announcement?
if ( details.id < 0 ) {
if ( listenCallback ) {
listenCallback(details.msg);
}
return;
}
var callback = requestIdToCallbackMap[details.id];
if ( !callback ) {
return;
}
callback(details.msg);
delete requestIdToCallbackMap[details.id];
checkDisconnect();
};
var start = function(name) {
port = chrome.runtime.connect({
name: name +
'/' +
String.fromCharCode(
Math.random() * 0x7FFF | 0,
Math.random() * 0x7FFF | 0,
Math.random() * 0x7FFF | 0,
Math.random() * 0x7FFF | 0
)
});
port.onMessage.addListener(onPortMessage);
};
if ( typeof name === 'string' && name.length > 0 ) {
start(name);
}
var stop = function() {
listenCallback = null;
dangling = true;
checkDisconnect();
};
var ask = function(msg, callback) {
if ( !callback ) {
tell(msg);
return;
}
var id = requestId++;
port.postMessage({ id: id, msg: msg });
requestIdToCallbackMap[id] = callback;
};
var tell = function(msg) {
port.postMessage({ id: 0, msg: msg });
};
var listen = function(callback) {
listenCallback = callback;
};
var checkDisconnect = function() {
if ( !dangling ) {
return;
}
if ( Object.keys(requestIdToCallbackMap).length ) {
return;
}
port.disconnect();
port = null;
};
return {
start: start,
stop: stop,
ask: ask,
tell: tell,
listen: listen
};
})('contentscript-start.js');
/******************************************************************************/
/******************************************************************************/
// Domain-based ABP cosmetic filters.
// These can be inserted before the DOM is loaded.
var domainCosmeticFilteringHandler = function(selectors) {
if ( !selectors ) {
return;
}
var styleText = [];
if ( selectors.hide.length ) {
var hideStyleText = '{{hideSelectors}} {display:none !important;}'
.replace('{{hideSelectors}}', selectors.hide.join(','));
styleText.push(hideStyleText);
domainCosmeticFilteringApplyCSS(selectors.hide, 'display', 'none');
//console.debug('µBlock> "%s" cosmetic filters: injecting %d CSS rules:', selectors.domain, selectors.hide.length, hideStyleText);
}
if ( selectors.donthide.length ) {
var dontHideStyleText = '{{donthideSelectors}} {display:initial !important;}'
.replace('{{donthideSelectors}}', selectors.donthide.join(','));
styleText.push(dontHideStyleText);
domainCosmeticFilteringApplyCSS(selectors.donthide, 'display', 'initial');
//console.debug('µBlock> "%s" cosmetic filters: injecting %d CSS rules:', selectors.domain, selectors.donthide.length, dontHideStyleText);
}
if ( styleText.length > 0 ) {
var style = document.createElement('style');
style.appendChild(document.createTextNode(styleText.join('\n')));
var parent = document.head || document.documentElement;
if ( parent ) {
parent.appendChild(style);
}
}
};
var domainCosmeticFilteringApplyCSS = function(selectors, prop, value) {
if ( document.body === null ) {
return;
}
var elems = document.querySelectorAll(selectors);
var i = elems.length;
while ( i-- ) {
elems[i].style[prop] = value;
}
};
messaging.ask(
{
what: 'retrieveDomainCosmeticSelectors',
pageURL: window.location.href,
locationURL: window.location.href
},
domainCosmeticFilteringHandler
);
/******************************************************************************/
/******************************************************************************/
// The port will never be used again at this point, disconnecting allows
// the browser to flush this script from memory.
messaging.stop();
/******************************************************************************/
/******************************************************************************/
})();
/******************************************************************************/