NS_IMETHODIMP
nsTransactionManager::PeekRedoStack(nsITransaction **aTransaction)
{
nsRefPtr<nsTransactionItem> tx;
nsresult result;
NS_ENSURE_TRUE(aTransaction, NS_ERROR_NULL_POINTER);
*aTransaction = 0;
LOCK_TX_MANAGER(this);
result = mRedoStack.Peek(getter_AddRefs(tx));
if (NS_FAILED(result) || !tx) {
UNLOCK_TX_MANAGER(this);
return result;
}
result = tx->GetTransaction(aTransaction);
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::EndBatch()
{
nsRefPtr<nsTransactionItem> tx;
nsCOMPtr<nsITransaction> ti;
nsresult result;
LOCK_TX_MANAGER(this);
// XXX: Need to add some mechanism to detect the case where the transaction
// at the top of the do stack isn't the dummy transaction, so we can
// throw an error!! This can happen if someone calls EndBatch() within
// the DoTransaction() method of a transaction.
//
// For now, we can detect this case by checking the value of the
// dummy transaction's mTransaction field. If it is our dummy
// transaction, it should be NULL. This may not be true in the
// future when we allow users to execute a transaction when beginning
// a batch!!!!
result = mDoStack.Peek(getter_AddRefs(tx));
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (tx)
tx->GetTransaction(getter_AddRefs(ti));
if (!tx || ti) {
UNLOCK_TX_MANAGER(this);
return NS_ERROR_FAILURE;
}
PRBool doInterrupt = PR_FALSE;
result = WillEndBatchNotify(&doInterrupt);
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (doInterrupt) {
UNLOCK_TX_MANAGER(this);
return NS_OK;
}
result = EndTransaction();
nsresult result2 = DidEndBatchNotify(result);
if (NS_SUCCEEDED(result))
result = result2;
UNLOCK_TX_MANAGER(this);
return result;
}
nsresult
nsTransactionManager::ClearRedoStack()
{
nsresult result;
LOCK_TX_MANAGER(this);
result = mRedoStack.Clear();
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::GetMaxTransactionCount(PRInt32 *aMaxCount)
{
NS_ENSURE_TRUE(aMaxCount, NS_ERROR_NULL_POINTER);
LOCK_TX_MANAGER(this);
*aMaxCount = mMaxTransactionCount;
UNLOCK_TX_MANAGER(this);
return NS_OK;
}
NS_IMETHODIMP
nsTransactionManager::GetNumberOfRedoItems(PRInt32 *aNumItems)
{
nsresult result;
LOCK_TX_MANAGER(this);
result = mRedoStack.GetSize(aNumItems);
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::RemoveListener(nsITransactionListener *aListener)
{
NS_ENSURE_TRUE(aListener, NS_ERROR_NULL_POINTER);
LOCK_TX_MANAGER(this);
nsresult rv = mListeners.RemoveObject(aListener) ? NS_OK : NS_ERROR_FAILURE;
UNLOCK_TX_MANAGER(this);
return rv;
}
NS_IMETHODIMP
nsTransactionManager::AddListener(nsITransactionListener *aListener)
{
if (!aListener)
return NS_ERROR_NULL_POINTER;
LOCK_TX_MANAGER(this);
nsresult rv = mListeners.AppendObject(aListener) ? NS_OK : NS_ERROR_FAILURE;
UNLOCK_TX_MANAGER(this);
return rv;
}
NS_IMETHODIMP
nsTransactionManager::DoTransaction(nsITransaction *aTransaction)
{
nsresult result;
if (!aTransaction)
return NS_ERROR_NULL_POINTER;
LOCK_TX_MANAGER(this);
PRBool doInterrupt = PR_FALSE;
result = WillDoNotify(aTransaction, &doInterrupt);
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (doInterrupt) {
UNLOCK_TX_MANAGER(this);
return NS_OK;
}
result = BeginTransaction(aTransaction);
if (NS_FAILED(result)) {
DidDoNotify(aTransaction, result);
UNLOCK_TX_MANAGER(this);
return result;
}
result = EndTransaction();
nsresult result2 = DidDoNotify(aTransaction, result);
if (NS_SUCCEEDED(result))
result = result2;
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::Clear()
{
nsresult result;
LOCK_TX_MANAGER(this);
result = ClearRedoStack();
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
result = ClearUndoStack();
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::BeginBatch()
{
nsresult result;
// We can batch independent transactions together by simply pushing
// a dummy transaction item on the do stack. This dummy transaction item
// will be popped off the do stack, and then pushed on the undo stack
// in EndBatch().
LOCK_TX_MANAGER(this);
PRBool doInterrupt = PR_FALSE;
result = WillBeginBatchNotify(&doInterrupt);
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (doInterrupt) {
UNLOCK_TX_MANAGER(this);
return NS_OK;
}
result = BeginTransaction(0);
nsresult result2 = DidBeginBatchNotify(result);
if (NS_SUCCEEDED(result))
result = result2;
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::SetMaxTransactionCount(PRInt32 aMaxCount)
{
PRInt32 numUndoItems = 0, numRedoItems = 0, total = 0;
nsRefPtr<nsTransactionItem> tx;
nsresult result;
LOCK_TX_MANAGER(this);
// It is illegal to call SetMaxTransactionCount() while the transaction
// manager is executing a transaction's DoTransaction() method because
// the undo and redo stacks might get pruned! If this happens, the
// SetMaxTransactionCount() request is ignored, and we return
// NS_ERROR_FAILURE.
result = mDoStack.Peek(getter_AddRefs(tx));
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (tx) {
UNLOCK_TX_MANAGER(this);
return NS_ERROR_FAILURE;
}
// If aMaxCount is less than zero, the user wants unlimited
// levels of undo! No need to prune the undo or redo stacks!
if (aMaxCount < 0) {
mMaxTransactionCount = -1;
UNLOCK_TX_MANAGER(this);
return result;
}
result = mUndoStack.GetSize(&numUndoItems);
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
result = mRedoStack.GetSize(&numRedoItems);
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
total = numUndoItems + numRedoItems;
// If aMaxCount is greater than the number of transactions that currently
// exist on the undo and redo stack, there is no need to prune the
// undo or redo stacks!
if (aMaxCount > total ) {
mMaxTransactionCount = aMaxCount;
UNLOCK_TX_MANAGER(this);
return result;
}
// Try getting rid of some transactions on the undo stack! Start at
// the bottom of the stack and pop towards the top.
while (numUndoItems > 0 && (numRedoItems + numUndoItems) > aMaxCount) {
result = mUndoStack.PopBottom(getter_AddRefs(tx));
if (NS_FAILED(result) || !tx) {
UNLOCK_TX_MANAGER(this);
return result;
}
--numUndoItems;
}
// If necessary, get rid of some transactions on the redo stack! Start at
// the bottom of the stack and pop towards the top.
while (numRedoItems > 0 && (numRedoItems + numUndoItems) > aMaxCount) {
result = mRedoStack.PopBottom(getter_AddRefs(tx));
if (NS_FAILED(result) || !tx) {
UNLOCK_TX_MANAGER(this);
return result;
}
--numRedoItems;
}
mMaxTransactionCount = aMaxCount;
UNLOCK_TX_MANAGER(this);
return result;
}
NS_IMETHODIMP
nsTransactionManager::RedoTransaction()
{
nsresult result = NS_OK;
nsRefPtr<nsTransactionItem> tx;
LOCK_TX_MANAGER(this);
// It is illegal to call RedoTransaction() while the transaction manager is
// executing a transaction's DoTransaction() method! If this happens,
// the RedoTransaction() request is ignored, and we return NS_ERROR_FAILURE.
result = mDoStack.Peek(getter_AddRefs(tx));
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (tx) {
UNLOCK_TX_MANAGER(this);
return NS_ERROR_FAILURE;
}
// Peek at the top of the redo stack. Don't remove the transaction
// until it has successfully completed.
result = mRedoStack.Peek(getter_AddRefs(tx));
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
// Bail if there's nothing on the stack.
if (!tx) {
UNLOCK_TX_MANAGER(this);
return NS_OK;
}
nsCOMPtr<nsITransaction> t;
result = tx->GetTransaction(getter_AddRefs(t));
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
PRBool doInterrupt = PR_FALSE;
result = WillRedoNotify(t, &doInterrupt);
if (NS_FAILED(result)) {
UNLOCK_TX_MANAGER(this);
return result;
}
if (doInterrupt) {
UNLOCK_TX_MANAGER(this);
return NS_OK;
}
result = tx->RedoTransaction(this);
if (NS_SUCCEEDED(result)) {
result = mRedoStack.Pop(getter_AddRefs(tx));
if (NS_SUCCEEDED(result))
result = mUndoStack.Push(tx);
}
nsresult result2 = DidRedoNotify(t, result);
if (NS_SUCCEEDED(result))
result = result2;
UNLOCK_TX_MANAGER(this);
return result;
}
