gecko-dev/netwerk/test/TestCacheCollisions.js

292 строки
8.0 KiB
JavaScript

var DEBUG = true;
var clientID = "HTTP";
var nsICache = Components.interfaces.nsICache;
function getEventQueue()
{
var nsIEventQueueService = Components.interfaces.nsIEventQueueService;
var CID = Components.classes["@mozilla.org/event-queue-service;1"];
var service = CID.getService(nsIEventQueueService);
return service.getSpecialEventQueue(nsIEventQueueService.CURRENT_THREAD_EVENT_QUEUE);
}
var eventQueue = getEventQueue();
function getCacheService()
{
var nsCacheService = Components.classes["@mozilla.org/network/cache-service;1"];
var service = nsCacheService.getService(Components.interfaces.nsICacheService);
return service;
}
function createCacheSession(clientID, storagePolicy, streamable)
{
var service = getCacheService();
var session = service.createSession(clientID, storagePolicy, streamable);
return session;
}
function openCacheEntry(url, mode)
{
var session = createCacheSession(clientID, nsICache.STORE_ON_DISK, true);
var entry = session.openCacheEntry(url, mode);
return entry;
}
function wrapInputStream(input)
{
var nsIScriptableInputStream = Components.interfaces.nsIScriptableInputStream;
var factory = Components.classes["@mozilla.org/scriptableinputstream;1"];
var wrapper = factory.createInstance(nsIScriptableInputStream);
wrapper.init(input);
return wrapper;
}
function download(key)
{
var url = new java.net.URL(key);
var data = "";
var buffer = java.lang.reflect.Array.newInstance(java.lang.Byte.TYPE, 65536);
var stream = url.openStream();
while (true) {
var count = stream.read(buffer);
if (count <= 0)
break;
var str = new java.lang.String(buffer, 0, count);
data += str;
}
stream.close();
return data;
}
function write(url, data)
{
var key = url.toString();
var outputEntry = openCacheEntry(key, nsICache.ACCESS_WRITE);
var output = outputEntry.transport.openOutputStream(0, -1, 0);
var count = output.write(data, data.length);
// store some metadata.
outputEntry.setMetaDataElement("size", data.length);
output.close();
outputEntry.markValid();
outputEntry.close();
return count;
}
function CacheListener()
{
this.done = false;
}
CacheListener.prototype = {
QueryInterface : function(iid)
{
if (iid.equals(Components.interfaces.nsICacheListener))
return this;
throw Components.results.NS_NOINTERFACE;
},
onCacheEntryAvailable : function(/* in nsICacheEntryDescriptor */ descriptor,
/* in nsCacheAccessMode */ accessGranted,
/* in nsresult */ status)
{
this.descriptor = descriptor;
this.status = status;
this.done = true;
}
};
function asyncOpenCacheEntry(url, mode)
{
var session = createCacheSession(clientID, nsICache.STORE_ON_DISK, true);
var listener = new CacheListener();
session.asyncOpenCacheEntry(url, mode, listener);
while (!listener.done)
eventQueue.processPendingEvents();
return listener.descriptor;
}
function asyncWrite(key, data)
{
var outputEntry = asyncOpenCacheEntry(key, nsICache.ACCESS_WRITE);
var output = outputEntry.transport.openOutputStream(0, -1, 0);
var count = output.write(data, data.length);
// store some metadata.
outputEntry.setMetaDataElement("size", data.length);
output.close();
outputEntry.markValid();
outputEntry.close();
return count;
}
function StreamListener()
{
this.done = false;
this.data = "";
this.wrapper = null;
}
StreamListener.prototype = {
QueryInterface : function(iid)
{
if (iid.equals(Components.interfaces.nsIStreamListener) ||
iid.equals(Components.interfaces.nsIStreamObserver))
return this;
throw Components.results.NS_NOINTERFACE;
},
onStartRequest : function(request, context)
{
},
onStopRequest : function(request, context, statusCode, statusText)
{
this.statusCode = statusCode;
this.done = true;
},
onDataAvailable : function(request, context, input, offset, count)
{
if (this.wrapper == null)
this.wrapper = wrapInputStream(input);
input = this.wrapper;
this.data += input.read(count);
}
};
function asyncRead(key)
{
var inputEntry = asyncOpenCacheEntry(key, nsICache.ACCESS_READ);
var listener = new StreamListener();
inputEntry.transport.asyncRead(listener, null, 0, inputEntry.dataSize, 0);
while (!listener.done)
eventQueue.processPendingEvents();
inputEntry.close();
return listener.data;
}
function read(key)
{
var inputEntry = openCacheEntry(key, nsICache.ACCESS_READ);
var input = wrapInputStream(inputEntry.transport.openInputStream(0, -1, 0));
var data = input.read(input.available());
input.close();
inputEntry.close();
return data;
}
function readMetaData(key, element)
{
var inputEntry = openCacheEntry(key, nsICache.ACCESS_READ);
var metadata = inputEntry.getMetaDataElement(element);
inputEntry.close();
return metadata;
}
function doom(url)
{
var key = url.toString();
var doomedEntry = openCacheEntry(key, nsICache.ACCESS_READ_WRITE);
doomedEntry.doom();
doomedEntry.close();
}
// two keys which are known to collide right now.
var key1 = "http://a772.g.akamai.net/7/772/51/7648437e551b56/www.apple.com/t/2001/us/en/i/2.gif";
var key2 = "http://a772.g.akamai.net/7/772/51/70601300d0bde6/www.apple.com/t/2001/us/en/i/1right.gif";
function test()
{
// 1. generate a collision, and close the colliding entry first.
var entry1 = asyncOpenCacheEntry(key1, nsICache.ACCESS_READ_WRITE);
var data1 = key1;
entry1.setMetaDataElement("size", data1.length);
entry1.markValid();
var output1 = entry1.transport.openOutputStream(0, -1, 0);
output1.write(data1, data1.length);
var entry2 = asyncOpenCacheEntry(key2, nsICache.ACCESS_READ_WRITE);
var data2 = key2;
entry2.setMetaDataElement("size", data2.length);
entry2.markValid();
var output2 = entry2.transport.openOutputStream(0, -1, 0);
output2.write(data2, data2.length);
output1.close();
output2.close();
entry1.close();
entry2.close();
}
function median(array)
{
var cmp = function(x, y) { return x - y; }
array.sort(cmp);
var middle = Math.floor(array.length / 2);
return array[middle];
}
function sum(array)
{
var s = 0;
var len = array.length;
for (var i = 0; i < len; ++i)
s += array[i];
return s;
}
function time()
{
var N = 50;
var System = java.lang.System;
var url = new java.net.URL("http://www.mozilla.org");
var key = url.toString();
var downloadTimes = new Array();
for (var i = 0; i < N; ++i) {
var begin = System.currentTimeMillis();
download(url);
var end = System.currentTimeMillis();
downloadTimes.push(end - begin);
}
var downloadTotal = sum(downloadTimes);
var downloadMean = downloadTotal / N;
var downloadMedian = median(downloadTimes);
print("" + N + " downloads took " + downloadTotal + " milliseconds.");
print("mean = " + downloadMean + " milliseconds.");
print("median = " + downloadMedian + " milliseconds.");
var readTimes = new Array();
for (var i = 0; i < N; ++i) {
var begin = System.currentTimeMillis();
asyncRead(key);
var end = System.currentTimeMillis();
readTimes.push(end - begin);
}
var readTotal = sum(readTimes);
var readMean = readTotal / N;
var readMedian = median(readTimes);
print("" + N + " reads took " + readTotal + " milliseconds.");
print("mean = " + readMean + " milliseconds.");
print("median = " + readMedian + " milliseconds.");
}
// load the cache service before doing anything with Java...
getCacheService();
if (DEBUG) {
print("cache service loaded.");
} else {
print("running disk cache test.");
test();
print("disk cache test complete.");
}