nsresult
nsTextEditRules::TruncateInsertionIfNeeded(Selection* aSelection,
const nsAString *aInString,
nsAString *aOutString,
int32_t aMaxLength,
bool *aTruncated)
{
if (!aSelection || !aInString || !aOutString) {return NS_ERROR_NULL_POINTER;}
nsresult res = NS_OK;
*aOutString = *aInString;
if (aTruncated) {
*aTruncated = false;
}
NS_ENSURE_STATE(mEditor);
if ((-1 != aMaxLength) && IsPlaintextEditor() && !mEditor->IsIMEComposing() )
{
// Get the current text length.
// Get the length of inString.
// Get the length of the selection.
// If selection is collapsed, it is length 0.
// Subtract the length of the selection from the len(doc)
// since we'll delete the selection on insert.
// This is resultingDocLength.
// Get old length of IME composing string
// which will be replaced by new one.
// If (resultingDocLength) is at or over max, cancel the insert
// If (resultingDocLength) + (length of input) > max,
// set aOutString to subset of inString so length = max
int32_t docLength;
res = mEditor->GetTextLength(&docLength);
if (NS_FAILED(res)) { return res; }
int32_t start, end;
nsContentUtils::GetSelectionInTextControl(aSelection, mEditor->GetRoot(),
start, end);
TextComposition* composition = mEditor->GetComposition();
int32_t oldCompStrLength = composition ? composition->String().Length() : 0;
const int32_t selectionLength = end - start;
const int32_t resultingDocLength = docLength - selectionLength - oldCompStrLength;
if (resultingDocLength >= aMaxLength)
{
aOutString->Truncate();
if (aTruncated) {
*aTruncated = true;
}
}
else
{
int32_t inCount = aOutString->Length();
if (inCount + resultingDocLength > aMaxLength)
{
aOutString->Truncate(aMaxLength - resultingDocLength);
if (aTruncated) {
*aTruncated = true;
}
}
}
}
return res;
}
nsresult
TextEditRules::TruncateInsertionIfNeeded(Selection* aSelection,
const nsAString* aInString,
nsAString* aOutString,
int32_t aMaxLength,
bool* aTruncated)
{
if (!aSelection || !aInString || !aOutString) {
return NS_ERROR_NULL_POINTER;
}
if (!aOutString->Assign(*aInString, mozilla::fallible)) {
return NS_ERROR_OUT_OF_MEMORY;
}
if (aTruncated) {
*aTruncated = false;
}
NS_ENSURE_STATE(mTextEditor);
if (-1 != aMaxLength && IsPlaintextEditor() &&
!mTextEditor->IsIMEComposing()) {
// Get the current text length.
// Get the length of inString.
// Get the length of the selection.
// If selection is collapsed, it is length 0.
// Subtract the length of the selection from the len(doc)
// since we'll delete the selection on insert.
// This is resultingDocLength.
// Get old length of IME composing string
// which will be replaced by new one.
// If (resultingDocLength) is at or over max, cancel the insert
// If (resultingDocLength) + (length of input) > max,
// set aOutString to subset of inString so length = max
int32_t docLength;
nsresult rv = mTextEditor->GetTextLength(&docLength);
if (NS_FAILED(rv)) {
return rv;
}
uint32_t start, end;
nsContentUtils::GetSelectionInTextControl(aSelection,
mTextEditor->GetRoot(),
start, end);
TextComposition* composition = mTextEditor->GetComposition();
uint32_t oldCompStrLength = composition ? composition->String().Length() : 0;
const uint32_t selectionLength = end - start;
const int32_t resultingDocLength = docLength - selectionLength - oldCompStrLength;
if (resultingDocLength >= aMaxLength) {
// This call is guaranteed to reduce the capacity of the string, so it
// cannot cause an OOM.
aOutString->Truncate();
if (aTruncated) {
*aTruncated = true;
}
} else {
int32_t oldLength = aOutString->Length();
if (oldLength + resultingDocLength > aMaxLength) {
int32_t newLength = aMaxLength - resultingDocLength;
MOZ_ASSERT(newLength > 0);
char16_t newLastChar = aOutString->CharAt(newLength - 1);
char16_t removingFirstChar = aOutString->CharAt(newLength);
// Don't separate the string between a surrogate pair.
if (NS_IS_HIGH_SURROGATE(newLastChar) &&
NS_IS_LOW_SURROGATE(removingFirstChar)) {
newLength--;
}
// XXX What should we do if we're removing IVS and its preceding
// character won't be removed?
// This call is guaranteed to reduce the capacity of the string, so it
// cannot cause an OOM.
aOutString->Truncate(newLength);
if (aTruncated) {
*aTruncated = true;
}
}
}
}
return NS_OK;
}
