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#include "messagequeue.h"
#include "storage.h"
#include <QDebug>
#include <log.h>
MessageQueue::MessageQueue(const QString &storageRoot, const QString &name)
: mStorage(storageRoot, name, Akonadi2::Storage::ReadWrite)
{
}
void MessageQueue::enqueue(void const *msg, size_t size)
{
auto transaction = std::move(mStorage.createTransaction(Akonadi2::Storage::ReadWrite));
const qint64 revision = Akonadi2::Storage::maxRevision(transaction) + 1;
const QByteArray key = QString("%1").arg(revision).toUtf8();
transaction.write(key, QByteArray::fromRawData(static_cast<const char*>(msg), size));
Akonadi2::Storage::setMaxRevision(transaction, revision);
transaction.commit();
emit messageReady();
}
void MessageQueue::enqueue(const QByteArray &value)
{
enqueue(value.data(), value.size());
}
void MessageQueue::dequeue(const std::function<void(void *ptr, int size, std::function<void(bool success)>)> &resultHandler,
const std::function<void(const Error &error)> &errorHandler)
{
bool readValue = false;
auto readTransaction = std::move(mStorage.createTransaction(Akonadi2::Storage::ReadOnly));
readTransaction.scan("", [this, resultHandler, errorHandler, &readValue, &readTransaction](const QByteArray &key, const QByteArray &value) -> bool {
if (Akonadi2::Storage::isInternalKey(key)) {
return true;
}
readValue = true;
//We need a copy of the key here, otherwise we can't store it in the lambda (the pointers will become invalid)
const auto keyCopy = QByteArray(key.constData(), key.size());
//TODO The value copy and the early transaction abort is necessary because we don't support parallel read-transactions yet (in case of a synchronous callback)
const auto valueCopy = QByteArray(value.constData(), value.size());
readTransaction.abort();
resultHandler(const_cast<void*>(static_cast<const void*>(valueCopy.data())), valueCopy.size(), [this, keyCopy, errorHandler](bool success) {
if (success) {
mStorage.createTransaction(Akonadi2::Storage::ReadWrite).remove(keyCopy, [errorHandler, keyCopy](const Akonadi2::Storage::Error &error) {
ErrorMsg() << "Error while removing value" << error.message << keyCopy;
//Don't call the errorhandler in here, we already called the result handler
});
mTransaction.commit();
if (isEmpty()) {
emit this->drained();
}
} else {
//TODO re-enqueue?
}
});
return false;
},
[errorHandler](const Akonadi2::Storage::Error &error) {
ErrorMsg() << "Error while retrieving value" << error.message;
errorHandler(Error(error.store, error.code, error.message));
}
);
if (!readValue) {
errorHandler(Error("messagequeue", -1, "No message found"));
}
}
bool MessageQueue::isEmpty()
{
int count = 0;
mStorage.createTransaction(Akonadi2::Storage::ReadOnly).scan("", [&count](const QByteArray &key, const QByteArray &value) -> bool {
if (!Akonadi2::Storage::isInternalKey(key)) {
count++;
return false;
}
return true;
},
[](const Akonadi2::Storage::Error &error) {
qDebug() << "Error while checking if empty" << error.message;
});
return count == 0;
}
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