FileLoaderProxy.cpp Example File

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    #include "FileLoaderProxy.hpp"

    // The key that is used for the shared memory segment
    static const char *s_sharedKey = "fileloader_shm_key";

    // The size of the shared memory segment
    static const int s_memorySize = 10 * 1024; // 10kB

    FileLoaderProxy::FileLoaderProxy(QObject *parent)
        : QObject(parent)
    {
        // Define the key that identifies this shared memory segment
        m_sharedMemory.setKey(QString::fromLatin1(s_sharedKey));

        // Create the shared memory segment with the given size
        m_sharedMemory.create(s_memorySize);
    }

    QString FileLoaderProxy::fileContent() const
    {
        // Before we access the content of the shared memory we should lock it
        m_sharedMemory.lock();

        // Read out all data
        QString content = QString::fromUtf8(static_cast<char*>(m_sharedMemory.data()));
        if (content.isEmpty())
            content = tr("No file loaded yet, please use sharedmemory_loader sample application to load one.");

        // Unlock the shared memory again
        m_sharedMemory.unlock();

        return content;
    }

    void FileLoaderProxy::loadFile()
    {
        /**
         * We expect that the user has started the sharedmemory_loader example and loaded
         * a file into the shared memory already, so just trigger to read the data from the
         * shared memory.
         */
        emit fileContentChanged();
    }