gecko/xpcom/io/nsMediaCacheRemover.cpp
2011-10-17 10:59:28 -04:00

151 lines
5.8 KiB
C++

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla code.
*
* The Initial Developer of the Original Code is
* the Mozilla Foundation.
* Portions created by the Initial Developer are Copyright (C) 2010
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Chris Pearce <chris@pearce.org.nz>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef XP_WIN
#error nsMediaCacheRemover only needed on Windows.
#endif
#include "nsIObserver.h"
#include "nsIIdleService.h"
#include "nsISimpleEnumerator.h"
#include "nsILocalFile.h"
#include "nsAppDirectoryServiceDefs.h"
#include "nsDirectoryServiceDefs.h"
#include "nsString.h"
#include "nsAutoPtr.h"
#include "nsITimer.h"
// Duration of idle time before we'll get a callback whereupon we attempt to
// remove any stray and unused media cache temp files.
#define TEMP_FILE_IDLE_TIME 30
// The nsMediaCacheRemover is created in a timer, which sets an idle observer.
// This is expiration time (in ms) which initial timer is set for (3 minutes).
#define SCHEDULE_TIMEOUT 3 * 60 * 1000
// This class adds itself as an idle observer. When the application has
// been idle for about 30 seconds we'll get a notification, whereupon we'll
// attempt to delete ${TempDir}/mozilla-media-cache/. This is to ensure all
// media cache temp files which were supposed to be deleted on application
// exit were actually deleted as they may not be if we previously crashed.
// See bug 572579. This is only needed on some versions of Windows,
// nsILocalFile::DELETE_ON_CLOSE works on other platforms.
class nsMediaCacheRemover : public nsIObserver {
public:
NS_DECL_ISUPPORTS
nsMediaCacheRemover() {
MOZ_COUNT_CTOR(nsMediaCacheRemover);
}
~nsMediaCacheRemover() {
MOZ_COUNT_DTOR(nsMediaCacheRemover);
}
NS_IMETHODIMP Observe(nsISupports *subject,
const char *topic,
const PRUnichar *data)
{
if (strcmp(topic, "idle") == 0) {
// The user has been idle for a while, clean up the temp files.
// The idle service will drop its reference to this object after
// we exit, destroying this object.
RemoveMediaCacheFiles();
}
return NS_OK;
}
nsresult RegisterIdleObserver() {
// Add this as an idle observer. When we've been idle for
// TEMP_FILE_IDLE_TIME seconds, we'll get a notification, and we'll then
// try to delete any stray media cache temp files.
nsCOMPtr<nsIIdleService> idleSvc =
do_GetService("@mozilla.org/widget/idleservice;1");
if (!idleSvc)
return NS_ERROR_FAILURE;
return idleSvc->AddIdleObserver(this, TEMP_FILE_IDLE_TIME);
}
void RemoveMediaCacheFiles() {
nsCOMPtr<nsIIdleService> idleSvc =
do_GetService("@mozilla.org/widget/idleservice;1");
if (idleSvc)
idleSvc->RemoveIdleObserver(this, TEMP_FILE_IDLE_TIME);
nsCOMPtr<nsIFile> tmpDir;
nsresult rv = NS_GetSpecialDirectory(NS_OS_TEMP_DIR,
getter_AddRefs(tmpDir));
if (NS_FAILED(rv))
return;
rv = tmpDir->AppendNative(nsDependentCString("mozilla-media-cache"));
if (NS_FAILED(rv))
return;
nsCOMPtr<nsILocalFile> tmpFile = do_QueryInterface(tmpDir);
if (!tmpFile)
return;
// Remove the directory recursively.
tmpFile->Remove(true);
}
};
NS_IMPL_ISUPPORTS1(nsMediaCacheRemover, nsIObserver)
void CreateMediaCacheRemover(nsITimer* aTimer, void* aClosure) {
// Create a new nsMediaCacheRemover, and register it as an idle observer.
// If it is successfully registered as an idle observer, its owning reference
// will be held by the idle service, otherwise it will be destroyed by the
// refptr here when it goes out of scope.
nsRefPtr<nsMediaCacheRemover> t = new nsMediaCacheRemover();
t->RegisterIdleObserver();
}
nsresult ScheduleMediaCacheRemover() {
// We create the nsMediaCacheRemover in a timer, so that the app has enough
// time to start up before we add the idle observer. If we register the
// idle observer too early, it will be registered before the fake idle
// service is installed when running in xpcshell, and this interferes with
// the fake idle service, causing xpcshell-test failures.
nsCOMPtr<nsITimer> t = do_CreateInstance(NS_TIMER_CONTRACTID);
nsresult res = t->InitWithFuncCallback(CreateMediaCacheRemover,
0,
SCHEDULE_TIMEOUT,
nsITimer::TYPE_ONE_SHOT);
return res;
}