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mirror of https://github.com/strawberrymusicplayer/strawberry synced 2024-12-15 18:19:33 +01:00
strawberry-audio-player-win.../3rdparty/singleapplication/singlecoreapplication.cpp
2020-06-14 23:54:18 +02:00

198 lines
5.6 KiB
C++

// The MIT License (MIT)
//
// Copyright (c) Itay Grudev 2015 - 2018
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
// W A R N I N G !!!
// -----------------
//
// This is a modified version of SingleApplication,
// The original version is at:
//
// https://github.com/itay-grudev/SingleApplication
//
//
#include <cstdlib>
#include <limits>
#include <QtGlobal>
#include <QCoreApplication>
#include <QThread>
#include <QSharedMemory>
#include <QLocalSocket>
#include <QByteArray>
#include <QElapsedTimer>
#include <QtDebug>
#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
# include <QRandomGenerator>
#else
# include <QDateTime>
#endif
#include "singlecoreapplication.h"
#include "singlecoreapplication_p.h"
/**
* @brief Constructor. Checks and fires up LocalServer or closes the program
* if another instance already exists
* @param argc
* @param argv
* @param {bool} allowSecondaryInstances
*/
SingleCoreApplication::SingleCoreApplication(int &argc, char *argv[], bool allowSecondary, Options options, int timeout)
: app_t(argc, argv), d_ptr(new SingleCoreApplicationPrivate(this)) {
Q_D(SingleCoreApplication);
// Store the current mode of the program
d->options = options;
// Generating an application ID used for identifying the shared memory block and QLocalServer
d->genBlockServerName();
#ifdef Q_OS_UNIX
// By explicitly attaching it and then deleting it we make sure that the
// memory is deleted even after the process has crashed on Unix.
d->memory = new QSharedMemory(d->blockServerName);
d->memory->attach();
delete d->memory;
#endif
// Guarantee thread safe behaviour with a shared memory block.
d->memory = new QSharedMemory(d->blockServerName);
// Create a shared memory block
if (d->memory->create(sizeof(InstancesInfo))) {
// Initialize the shared memory block
d->memory->lock();
d->initializeMemoryBlock();
d->memory->unlock();
}
else {
// Attempt to attach to the memory segment
if (!d->memory->attach()) {
qCritical() << "SingleCoreApplication: Unable to attach to shared memory block.";
qCritical() << d->memory->errorString();
delete d;
::exit(EXIT_FAILURE);
}
}
InstancesInfo* inst = static_cast<InstancesInfo*>(d->memory->data());
QElapsedTimer time;
time.start();
// Make sure the shared memory block is initialised and in consistent state
while (true) {
d->memory->lock();
if(d->blockChecksum() == inst->checksum) break;
if (time.elapsed() > 5000) {
qWarning() << "SingleCoreApplication: Shared memory block has been in an inconsistent state from more than 5s. Assuming primary instance failure.";
d->initializeMemoryBlock();
}
d->memory->unlock();
// Random sleep here limits the probability of a collision between two racing apps
#if QT_VERSION >= QT_VERSION_CHECK(5, 10, 0)
QThread::sleep(QRandomGenerator::global()->bounded(8u, 18u));
#else
qsrand(QDateTime::currentMSecsSinceEpoch() % std::numeric_limits<uint>::max());
QThread::sleep(8 + static_cast<unsigned long>(static_cast <float>(qrand()) / RAND_MAX * 10));
#endif
}
if (inst->primary == false) {
d->startPrimary();
d->memory->unlock();
return;
}
// Check if another instance can be started
if (allowSecondary) {
inst->secondary += 1;
inst->checksum = d->blockChecksum();
d->instanceNumber = inst->secondary;
d->startSecondary();
if(d->options & Mode::SecondaryNotification) {
d->connectToPrimary(timeout, SingleCoreApplicationPrivate::SecondaryInstance);
}
d->memory->unlock();
return;
}
d->memory->unlock();
d->connectToPrimary(timeout, SingleCoreApplicationPrivate::NewInstance);
delete d;
::exit(EXIT_SUCCESS);
}
/**
* @brief Destructor
*/
SingleCoreApplication::~SingleCoreApplication() {
Q_D(SingleCoreApplication);
delete d;
}
bool SingleCoreApplication::isPrimary() {
Q_D(SingleCoreApplication);
return d->server != nullptr;
}
bool SingleCoreApplication::isSecondary() {
Q_D(SingleCoreApplication);
return d->server == nullptr;
}
quint32 SingleCoreApplication::instanceId() {
Q_D(SingleCoreApplication);
return d->instanceNumber;
}
qint64 SingleCoreApplication::primaryPid() {
Q_D(SingleCoreApplication);
return d->primaryPid();
}
bool SingleCoreApplication::sendMessage(QByteArray message, int timeout) {
Q_D(SingleCoreApplication);
// Nobody to connect to
if(isPrimary()) return false;
// Make sure the socket is connected
d->connectToPrimary(timeout, SingleCoreApplicationPrivate::Reconnect);
d->socket->write(message);
bool dataWritten = d->socket->waitForBytesWritten(timeout);
d->socket->flush();
return dataWritten;
}