CAPThread.cpp

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//=============================================================================
//  Includes
//=============================================================================

//  Self Include
#include "CAPThread.h"

//  PublicUtility Includes
#include "CADebugMacros.h"
#include "CAException.h"

//  System Includes
#if TARGET_OS_MAC
    #include <mach/mach.h>
#endif

//  Standard Library Includes
#include <stdio.h>

//==================================================================================================
//  CAPThread
//==================================================================================================

// returns the thread's priority as it was last set by the API
#define CAPTHREAD_SET_PRIORITY              0
// returns the thread's priority as it was last scheduled by the Kernel
#define CAPTHREAD_SCHEDULED_PRIORITY        1

//#define   Log_SetPriority                     1

CAPThread::CAPThread(ThreadRoutine inThreadRoutine, void* inParameter, UInt32 inPriority, bool inFixedPriority, bool inAutoDelete)
:
#if TARGET_OS_MAC
    mPThread(0),
    mSpawningThreadPriority(getScheduledPriority(pthread_self(), CAPTHREAD_SET_PRIORITY)),
#elif TARGET_OS_WIN32
    mThreadHandle(NULL),
    mThreadID(0),
#endif
    mThreadRoutine(inThreadRoutine),
    mThreadParameter(inParameter),
    mPriority(inPriority),
    mPeriod(0),
    mComputation(0),
    mConstraint(0),
    mIsPreemptible(true),
    mTimeConstraintSet(false),
    mFixedPriority(inFixedPriority),
    mAutoDelete(inAutoDelete)
{
}

CAPThread::CAPThread(ThreadRoutine inThreadRoutine, void* inParameter, UInt32 inPeriod, UInt32 inComputation, UInt32 inConstraint, bool inIsPreemptible, bool inAutoDelete)
:
#if TARGET_OS_MAC
    mPThread(0),
    mSpawningThreadPriority(getScheduledPriority(pthread_self(), CAPTHREAD_SET_PRIORITY)),
#elif TARGET_OS_WIN32
    mThreadHandle(NULL),
    mThreadID(0),
#endif
    mThreadRoutine(inThreadRoutine),
    mThreadParameter(inParameter),
    mPriority(kDefaultThreadPriority),
    mPeriod(inPeriod),
    mComputation(inComputation),
    mConstraint(inConstraint),
    mIsPreemptible(inIsPreemptible),
    mTimeConstraintSet(true),
    mFixedPriority(false),
    mAutoDelete(inAutoDelete)
{
}

CAPThread::~CAPThread()
{
}

UInt32  CAPThread::GetScheduledPriority()
{
#if TARGET_OS_MAC
    return CAPThread::getScheduledPriority( mPThread, CAPTHREAD_SCHEDULED_PRIORITY );
#elif TARGET_OS_WIN32
    UInt32 theAnswer = 0;
    if(mThreadHandle != NULL)
    {
        theAnswer = GetThreadPriority(mThreadHandle);
    }
    return theAnswer;
#endif
}

void    CAPThread::SetPriority(UInt32 inPriority, bool inFixedPriority)
{
    mPriority = inPriority;
    mTimeConstraintSet = false;
    mFixedPriority = inFixedPriority;
#if TARGET_OS_MAC
    if(mPThread != 0)
    {
        kern_return_t theError = 0;
        
        //  set whether or not this is a fixed priority thread
        if (mFixedPriority)
        {
            thread_extended_policy_data_t theFixedPolicy = { false };
            theError = thread_policy_set(pthread_mach_thread_np(mPThread), THREAD_EXTENDED_POLICY, (thread_policy_t)&theFixedPolicy, THREAD_EXTENDED_POLICY_COUNT);
            AssertNoKernelError(theError, "CAPThread::SetPriority: failed to set the fixed-priority policy");
        }
        
        //  set the thread's absolute priority which is relative to the priority on which thread_policy_set() is called
        UInt32 theCurrentThreadPriority = getScheduledPriority(pthread_self(), CAPTHREAD_SET_PRIORITY);
        thread_precedence_policy_data_t thePrecedencePolicy = { mPriority - theCurrentThreadPriority };
        theError = thread_policy_set(pthread_mach_thread_np(mPThread), THREAD_PRECEDENCE_POLICY, (thread_policy_t)&thePrecedencePolicy, THREAD_PRECEDENCE_POLICY_COUNT);
        AssertNoKernelError(theError, "CAPThread::SetPriority: failed to set the precedence policy");
        
        #if Log_SetPriority
            DebugMessageN4("CAPThread::SetPriority: requsted: %lu spawning: %lu current: %lu assigned: %d", mPriority, mSpawningThreadPriority, theCurrentThreadPriority, thePrecedencePolicy.importance);
        #endif
    } 
#elif TARGET_OS_WIN32
    if(mThreadHandle != NULL)
    {
        SetThreadPriority(mThreadHandle, mPriority);
    }
#endif
}

void    CAPThread::SetTimeConstraints(UInt32 inPeriod, UInt32 inComputation, UInt32 inConstraint, bool inIsPreemptible)
{
    mPeriod = inPeriod;
    mComputation = inComputation;
    mConstraint = inConstraint;
    mIsPreemptible = inIsPreemptible;
    mTimeConstraintSet = true;
#if TARGET_OS_MAC
    if(mPThread != 0)
    {
        thread_time_constraint_policy_data_t thePolicy;
        thePolicy.period = mPeriod;
        thePolicy.computation = mComputation;
        thePolicy.constraint = mConstraint;
        thePolicy.preemptible = mIsPreemptible;
        AssertNoError(thread_policy_set(pthread_mach_thread_np(mPThread), THREAD_TIME_CONSTRAINT_POLICY, (thread_policy_t)&thePolicy, THREAD_TIME_CONSTRAINT_POLICY_COUNT), "CAPThread::SetTimeConstraints: thread_policy_set failed");
    }
#elif TARGET_OS_WIN32
    if(mThreadHandle != NULL)
    {
        SetThreadPriority(mThreadHandle, THREAD_PRIORITY_TIME_CRITICAL);
    }
#endif
}

void    CAPThread::Start()
{
#if TARGET_OS_MAC
    Assert(mPThread == 0, "CAPThread::Start: can't start because the thread is already running");
    if(mPThread == 0)
    {
        OSStatus            theResult;
        pthread_attr_t      theThreadAttributes;
        
        theResult = pthread_attr_init(&theThreadAttributes);
        ThrowIf(theResult != 0, CAException(theResult), "CAPThread::Start: Thread attributes could not be created.");
        
        theResult = pthread_attr_setdetachstate(&theThreadAttributes, PTHREAD_CREATE_DETACHED);
        ThrowIf(theResult != 0, CAException(theResult), "CAPThread::Start: A thread could not be created in the detached state.");
        
        theResult = pthread_create(&mPThread, &theThreadAttributes, (ThreadRoutine)CAPThread::Entry, this);
        ThrowIf(theResult != 0 || !mPThread, CAException(theResult), "CAPThread::Start: Could not create a thread.");
        
        pthread_attr_destroy(&theThreadAttributes);
        
    }
#elif TARGET_OS_WIN32
    Assert(mThreadID == 0, "CAPThread::Start: can't start because the thread is already running");
    if(mThreadID == 0)
    {
        //  clean up the existing thread handle
        if(mThreadHandle != NULL)
        {
            CloseHandle(mThreadHandle);
            mThreadHandle = NULL;
        }
        
        //  create a new thread
        mThreadHandle = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)Entry, this, 0, &mThreadID);
        ThrowIf(mThreadHandle == NULL, CAException(GetLastError()), "CAPThread::Start: Could not create a thread.");
    }
#endif
}

#if TARGET_OS_MAC

void*   CAPThread::Entry(CAPThread* inCAPThread)
{
    void* theAnswer = NULL;

    try 
    {
        if(inCAPThread->mTimeConstraintSet)
        {
            inCAPThread->SetTimeConstraints(inCAPThread->mPeriod, inCAPThread->mComputation, inCAPThread->mConstraint, inCAPThread->mIsPreemptible);
        }
        else
        {
            inCAPThread->SetPriority(inCAPThread->mPriority, inCAPThread->mFixedPriority);
        }

        if(inCAPThread->mThreadRoutine != NULL)
        {
            theAnswer = inCAPThread->mThreadRoutine(inCAPThread->mThreadParameter);
        }
    }
    catch (...)
    {
        // what should be done here?
    }
    inCAPThread->mPThread = 0;
    if (inCAPThread->mAutoDelete)
        delete inCAPThread;
    return theAnswer;
}

UInt32 CAPThread::getScheduledPriority(pthread_t inThread, int inPriorityKind)
{
    thread_basic_info_data_t            threadInfo;
    policy_info_data_t                  thePolicyInfo;
    unsigned int                        count;

    if (inThread == NULL)
        return 0;
    
    // get basic info
    count = THREAD_BASIC_INFO_COUNT;
    thread_info (pthread_mach_thread_np (inThread), THREAD_BASIC_INFO, (thread_info_t)&threadInfo, &count);
    
    switch (threadInfo.policy) {
        case POLICY_TIMESHARE:
            count = POLICY_TIMESHARE_INFO_COUNT;
            thread_info(pthread_mach_thread_np (inThread), THREAD_SCHED_TIMESHARE_INFO, (thread_info_t)&(thePolicyInfo.ts), &count);
            if (inPriorityKind == CAPTHREAD_SCHEDULED_PRIORITY) {
                return thePolicyInfo.ts.cur_priority;
            }
            return thePolicyInfo.ts.base_priority;
            break;
            
        case POLICY_FIFO:
            count = POLICY_FIFO_INFO_COUNT;
            thread_info(pthread_mach_thread_np (inThread), THREAD_SCHED_FIFO_INFO, (thread_info_t)&(thePolicyInfo.fifo), &count);
            if ( (thePolicyInfo.fifo.depressed) && (inPriorityKind == CAPTHREAD_SCHEDULED_PRIORITY) ) {
                return thePolicyInfo.fifo.depress_priority;
            }
            return thePolicyInfo.fifo.base_priority;
            break;
            
        case POLICY_RR:
            count = POLICY_RR_INFO_COUNT;
            thread_info(pthread_mach_thread_np (inThread), THREAD_SCHED_RR_INFO, (thread_info_t)&(thePolicyInfo.rr), &count);
            if ( (thePolicyInfo.rr.depressed) && (inPriorityKind == CAPTHREAD_SCHEDULED_PRIORITY) ) {
                return thePolicyInfo.rr.depress_priority;
            }
            return thePolicyInfo.rr.base_priority;
            break;
    }
    
    return 0;
}

#elif TARGET_OS_WIN32

UInt32 WINAPI   CAPThread::Entry(CAPThread* inCAPThread)
{
    UInt32 theAnswer = 0;

    try 
    {
        if(inCAPThread->mTimeConstraintSet)
        {
            inCAPThread->SetTimeConstraints(inCAPThread->mPeriod, inCAPThread->mComputation, inCAPThread->mConstraint, inCAPThread->mIsPreemptible);
        }
        else
        {
            inCAPThread->SetPriority(inCAPThread->mPriority, inCAPThread->mFixedPriority);
        }

        if(inCAPThread->mThreadRoutine != NULL)
        {
            theAnswer = reinterpret_cast<UInt32>(inCAPThread->mThreadRoutine(inCAPThread->mThreadParameter));
        }
        inCAPThread->mThreadID = 0;
    }
    catch (...)
    {
        // what should be done here?
    }
    CloseHandle(inCAPThread->mThreadHandle);
    inCAPThread->mThreadHandle = NULL;
    if (inCAPThread->mAutoDelete)
        delete inCAPThread;
    return theAnswer;
}

extern "C"
Boolean CompareAndSwap(UInt32 inOldValue, UInt32 inNewValue, UInt32* inOldValuePtr)
{
    return InterlockedCompareExchange((volatile LONG*)inOldValuePtr, inNewValue, inOldValue) == inOldValue;
}

#endif

#if CoreAudio_Debug
void    CAPThread::DebugPriority(const char *label)
{
#if !TARGET_OS_WIN32
    if (mTimeConstraintSet)
        printf("CAPThread::%s %p: pri=<time constraint>, spawning pri=%d, scheduled pri=%d\n", label, this, 
        (int)mSpawningThreadPriority, (mPThread != NULL) ? (int)GetScheduledPriority() : -1);
    else
        printf("CAPThread::%s %p: pri=%d%s, spawning pri=%d, scheduled pri=%d\n", label, this, (int)mPriority, mFixedPriority ? " fixed" : "", 
        (int)mSpawningThreadPriority, (mPThread != NULL) ? (int)GetScheduledPriority() : -1);
#else
    if (mTimeConstraintSet)
    {
        printf("CAPThread::%s %p: pri=<time constraint>, spawning pri=%d, scheduled pri=%d\n", label, this, 
        (int)mPriority, (mThreadHandle != NULL) ? (int)GetScheduledPriority() : -1);
    }
    else
    {
        printf("CAPThread::%s %p: pri=%d%s, spawning pri=%d, scheduled pri=%d\n", label, this, (int)mPriority, mFixedPriority ? " fixed" : "", 
        (int)mPriority, (mThreadHandle != NULL) ? (int)GetScheduledPriority() : -1);
    }
#endif
}
#endif