/*!
Converts the variant map \a map to a QJsonObject.
The keys in \a map will be used as the keys in the JSON object,
and the QVariant values will be converted to JSON values.
\sa fromVariantHash(), toVariantMap(), QJsonValue::fromVariant()
*/
QJsonObject QJsonObject::fromVariantMap(const QVariantMap &map)
{
QJsonObject object;
if (map.isEmpty())
return object;
object.detach2(1024);
QVector<QJsonPrivate::offset> offsets;
QJsonPrivate::offset currentOffset;
currentOffset = sizeof(QJsonPrivate::Base);
// the map is already sorted, so we can simply append one entry after the other and
// write the offset table at the end
for (QVariantMap::const_iterator it = map.constBegin(); it != map.constEnd(); ++it) {
QString key = it.key();
QJsonValue val = QJsonValue::fromVariant(it.value());
bool latinOrIntValue;
int valueSize = QJsonPrivate::Value::requiredStorage(val, &latinOrIntValue);
bool latinKey = QJsonPrivate::useCompressed(key);
int valueOffset = sizeof(QJsonPrivate::Entry) + QJsonPrivate::qStringSize(key, latinKey);
int requiredSize = valueOffset + valueSize;
if (!object.detach2(requiredSize + sizeof(QJsonPrivate::offset))) // offset for the new index entry
return QJsonObject();
QJsonPrivate::Entry *e = reinterpret_cast<QJsonPrivate::Entry *>(reinterpret_cast<char *>(object.o) + currentOffset);
e->value.type = val.t;
e->value.latinKey = latinKey;
e->value.latinOrIntValue = latinOrIntValue;
e->value.value = QJsonPrivate::Value::valueToStore(val, (char *)e - (char *)object.o + valueOffset);
QJsonPrivate::copyString((char *)(e + 1), key, latinKey);
if (valueSize)
QJsonPrivate::Value::copyData(val, (char *)e + valueOffset, latinOrIntValue);
offsets << currentOffset;
currentOffset += requiredSize;
object.o->size = currentOffset;
}
// write table
object.o->tableOffset = currentOffset;
if (!object.detach2(sizeof(QJsonPrivate::offset)*offsets.size()))
return QJsonObject();
memcpy(object.o->table(), offsets.constData(), offsets.size()*sizeof(uint));
object.o->length = offsets.size();
object.o->size = currentOffset + sizeof(QJsonPrivate::offset)*offsets.size();
return object;
}
