nsresult imgRequestProxy::ChangeOwner(imgRequest *aNewOwner)
{
if (mCanceled)
return NS_OK;
// Were we decoded before?
PRBool wasDecoded = PR_FALSE;
if (mOwner->GetImageStatus() & imgIRequest::STATUS_FRAME_COMPLETE)
wasDecoded = PR_TRUE;
// If we're holding locks, unlock the old image.
// Note that UnlockImage decrements mLocksHeld each time it's called.
PRUint32 oldLockCount = mLocksHeld;
while (mLocksHeld)
UnlockImage();
// Passing false to aNotify means that mListener will still get
// OnStopRequest, if needed.
mOwner->RemoveProxy(this, NS_IMAGELIB_CHANGING_OWNER, PR_FALSE);
mOwner = aNewOwner;
mOwner->AddProxy(this);
// If we were decoded, or if we'd previously requested a decode, request a
// decode on the new image
if (wasDecoded || mDecodeRequested)
mOwner->RequestDecode();
// If we were locked, apply the locks here
for (PRUint32 i = 0; i < oldLockCount; i++)
LockImage();
return NS_OK;
}
imgRequestProxy::~imgRequestProxy()
{
/* destructor code */
NS_PRECONDITION(!mListener, "Someone forgot to properly cancel this request!");
// Unlock the image the proper number of times if we're holding locks on it.
// Note that UnlockImage() decrements mLocksHeld each time it's called.
if (mOwner) {
while (mLocksHeld)
UnlockImage();
}
// Explicitly set mListener to null to ensure that the RemoveProxy
// call below can't send |this| to an arbitrary listener while |this|
// is being destroyed. This is all belt-and-suspenders in view of the
// above assert.
NullOutListener();
if (mOwner) {
if (!mCanceled) {
mCanceled = PR_TRUE;
/* Call RemoveProxy with a successful status. This will keep the
channel, if still downloading data, from being canceled if 'this' is
the last observer. This allows the image to continue to download and
be cached even if no one is using it currently.
Passing false to aNotify means that we will still get
OnStopRequest, if needed.
*/
mOwner->RemoveProxy(this, NS_OK, PR_FALSE);
}
}
}
EXPORT(IMAGE) CloneImage(IMAGE image)
{
if (!image)
return NULL;
IMAGE clone = CreateImage(image->width, image->height, LockImage(image));
UnlockImage(image, false);
return clone;
}
