solarmutex.cxx

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#include <sal/config.h>

#include <comphelper/solarmutex.hxx>
#include <osl/thread.hxx>

#include <assert.h>
#include <cstdlib>

namespace comphelper {

namespace {
    static SolarMutex* g_pSolarMutex = nullptr;
}

SolarMutex *SolarMutex::get()
{
    return g_pSolarMutex;
}

SolarMutex::SolarMutex()
    : m_nCount( 0 )
    , m_nThreadId( 0 )
    , m_aBeforeReleaseHandler( nullptr )
{
    assert(!g_pSolarMutex);
    g_pSolarMutex = this;
}

SolarMutex::~SolarMutex()
{
    g_pSolarMutex = nullptr;
}

void SolarMutex::doAcquire( const sal_uInt32 nLockCount )
{
    for ( sal_uInt32 n = nLockCount; n ; --n )
        m_aMutex.acquire();
    m_nThreadId = osl::Thread::getCurrentIdentifier();
    m_nCount += nLockCount;
}

sal_uInt32 SolarMutex::doRelease( bool bUnlockAll )
{
    if ( !IsCurrentThread() )
        std::abort();
    if ( m_nCount == 0 )
        std::abort();

    const sal_uInt32 nCount = bUnlockAll ? m_nCount : 1;
    m_nCount -= nCount;

    if ( 0 == m_nCount )
    {
        if ( m_aBeforeReleaseHandler )
            m_aBeforeReleaseHandler();
        m_nThreadId = 0;
    }

    for ( sal_uInt32 n = nCount ; n ; --n )
        m_aMutex.release();

    return nCount;
}

bool SolarMutex::IsCurrentThread() const
{
    return m_nThreadId == osl::Thread::getCurrentIdentifier();
}

bool SolarMutex::tryToAcquire()
{
    if ( m_aMutex.tryToAcquire() )
    {
        m_nThreadId = osl::Thread::getCurrentIdentifier();
        m_nCount++;
        return true;
    }
    else
        return false;
}

} // namespace comphelper

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