gecko-dev/xpcom/io/nsMediaCacheRemover.cpp

119 строки
4.4 KiB
C++

/* 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/. */
#ifndef XP_WIN
#error nsMediaCacheRemover only needed on Windows.
#endif
#include "nsIObserver.h"
#include "nsIIdleService.h"
#include "nsISimpleEnumerator.h"
#include "nsIFile.h"
#include "nsAppDirectoryServiceDefs.h"
#include "nsDirectoryServiceDefs.h"
#include "nsXULAppAPI.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,
// nsIFile::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_APP_USER_PROFILE_LOCAL_50_DIR,
getter_AddRefs(tmpDir));
if (NS_FAILED(rv))
return;
NS_ABORT_IF_FALSE(XRE_GetProcessType() == GeckoProcessType_Default,
"Need to update media cache file location");
rv = tmpDir->AppendNative(nsDependentCString("mozilla-media-cache"));
if (NS_FAILED(rv))
return;
// Remove the directory recursively.
tmpDir->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;
}