actionlockguard.hxx

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#pragma once
 
#include <com/sun/star/document/XActionLockable.hpp>
#include <mutex>
 
namespace framework{
 
class ActionLockGuard final
{
 
    // member
 
    private:
        std::mutex m_mutex;
 
        css::uno::Reference< css::document::XActionLockable > m_xActionLock;
 
        bool m_bActionLocked;
 
    // interface
 
    public:
 
        ActionLockGuard()
            : m_bActionLocked(false)
        {
        }
 
        ~ActionLockGuard()
        {
            unlock();
        }
 
        bool setResource(const css::uno::Reference< css::document::XActionLockable >& xLock)
        {
            std::unique_lock g(m_mutex);
 
            if (m_bActionLocked || !xLock.is())
                return false;
 
            m_xActionLock = xLock;
            m_xActionLock->addActionLock();
            m_bActionLocked = m_xActionLock->isActionLocked();
 
            return true;
        }
 
        void freeResource()
        {
            // SAFE -> ..........................
            std::unique_lock aMutexLock(m_mutex);
 
            css::uno::Reference< css::document::XActionLockable > xLock   = m_xActionLock;
            bool                                                  bLocked = m_bActionLocked;
 
            m_xActionLock.clear();
            m_bActionLocked = false;
 
            aMutexLock.unlock();
            // <- SAFE ..........................
 
            if (bLocked && xLock.is())
                xLock->removeActionLock();
        }
 
        void unlock()
        {
            std::unique_lock g(m_mutex);
            if (m_bActionLocked && m_xActionLock.is())
            {
                m_xActionLock->removeActionLock();
                // don't check for any locks here ...
                // May another guard use the same lock object :-(
                m_bActionLocked = false;
            }
        }
};
 
} // namespace framework
 
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