gecko-dev/dom/media/doctor/DDLifetime.h

73 строки
2.6 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* 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 DDLifetime_h_
#define DDLifetime_h_
#include "DDLogObject.h"
#include "DDMessageIndex.h"
#include "DDTimeStamp.h"
namespace mozilla {
namespace dom {
class HTMLMediaElement;
} // namespace dom
// This struct records the lifetime of one C++ object.
// Note that multiple objects may have the same address and type (at different
// times), so the recorded construction/destruction times should be used to
// distinguish them.
struct DDLifetime {
const DDLogObject mObject;
const DDMessageIndex mConstructionIndex;
const DDTimeStamp mConstructionTimeStamp;
// Only valid when mDestructionTimeStamp is not null.
DDMessageIndex mDestructionIndex;
DDTimeStamp mDestructionTimeStamp;
// Associated HTMLMediaElement, initially nullptr until this object can be
// linked to its HTMLMediaElement.
const dom::HTMLMediaElement* mMediaElement;
// If not null, derived object for which this DDLifetime is a base class.
// This is used to link messages from the same object, even when they
// originate from a method on a base class.
// Note: We assume a single-inheritance hierarchy.
DDLogObject mDerivedObject;
DDMessageIndex mDerivedObjectLinkingIndex;
// Unique tag used to identify objects in a log, easier to read than object
// pointers.
// Negative and unique for unassociated objects.
// Positive for associated objects, and unique for that HTMLMediaElement
// group.
int32_t mTag;
DDLifetime(DDLogObject aObject, DDMessageIndex aConstructionIndex,
DDTimeStamp aConstructionTimeStamp, int32_t aTag)
: mObject(aObject),
mConstructionIndex(aConstructionIndex),
mConstructionTimeStamp(aConstructionTimeStamp),
mDestructionIndex(0),
mMediaElement(nullptr),
mDerivedObjectLinkingIndex(0),
mTag(aTag) {}
// Is this lifetime alive at the given index?
// I.e.: Constructed before, and destroyed later or not yet.
bool IsAliveAt(DDMessageIndex aIndex) const {
return aIndex >= mConstructionIndex &&
(!mDestructionTimeStamp || aIndex <= mDestructionIndex);
}
// Print the object's pointer, tag and class name (and derived class). E.g.:
// "dom::HTMLVideoElement[134073800]#1 (as dom::HTMLMediaElement)"
void AppendPrintf(nsCString& aString) const;
nsCString Printf() const;
};
} // namespace mozilla
#endif // DDLifetime_h_