/* Threads.c -- multithreading library
2023-03-04 : Igor Pavlov : Public domain */

#include "Precomp.h"

#ifdef _WIN32

#ifndef USE_THREADS_CreateThread
#include <process.h>
#endif

#include "Threads.h"

static WRes GetError(void)
{
  const DWORD res = GetLastError();
  return res ? (WRes)res : 1;
}

static WRes HandleToWRes(HANDLE h) { return (h != NULL) ? 0 : GetError(); }
static WRes BOOLToWRes(BOOL v) { return v ? 0 : GetError(); }

WRes HandlePtr_Close(HANDLE *p)
{
  if (*p != NULL)
  {
    if (!CloseHandle(*p))
      return GetError();
    *p = NULL;
  }
  return 0;
}

WRes Handle_WaitObject(HANDLE h)
{
  DWORD dw = WaitForSingleObject(h, INFINITE);
  /*
    (dw) result:
    WAIT_OBJECT_0  // 0
    WAIT_ABANDONED // 0x00000080 : is not compatible with Win32 Error space
    WAIT_TIMEOUT   // 0x00000102 : is     compatible with Win32 Error space
    WAIT_FAILED    // 0xFFFFFFFF
  */
  if (dw == WAIT_FAILED)
  {
    dw = GetLastError();
    if (dw == 0)
      return WAIT_FAILED;
  }
  return (WRes)dw;
}

#define Thread_Wait(p) Handle_WaitObject(*(p))

WRes Thread_Wait_Close(CThread *p)
{
  WRes res = Thread_Wait(p);
  WRes res2 = Thread_Close(p);
  return (res != 0 ? res : res2);
}

WRes Thread_Create(CThread *p, THREAD_FUNC_TYPE func, LPVOID param)
{
  /* Windows Me/98/95: threadId parameter may not be NULL in _beginthreadex/CreateThread functions */

  #ifdef USE_THREADS_CreateThread

  DWORD threadId;
  *p = CreateThread(NULL, 0, func, param, 0, &threadId);
  
  #else
  
  unsigned threadId;
  *p = (HANDLE)(_beginthreadex(NULL, 0, func, param, 0, &threadId));
  
  #endif

  /* maybe we must use errno here, but probably GetLastError() is also OK. */
  return HandleToWRes(*p);
}


WRes Thread_Create_With_Affinity(CThread *p, THREAD_FUNC_TYPE func, LPVOID param, CAffinityMask affinity)
{
  #ifdef USE_THREADS_CreateThread

  UNUSED_VAR(affinity)
  return Thread_Create(p, func, param);
  
  #else
  
  /* Windows Me/98/95: threadId parameter may not be NULL in _beginthreadex/CreateThread functions */
  HANDLE h;
  WRes wres;
  unsigned threadId;
  h = (HANDLE)(_beginthreadex(NULL, 0, func, param, CREATE_SUSPENDED, &threadId));
  *p = h;
  wres = HandleToWRes(h);
  if (h)
  {
    {
      // DWORD_PTR prevMask =
      SetThreadAffinityMask(h, (DWORD_PTR)affinity);
      /*
      if (prevMask == 0)
      {
        // affinity change is non-critical error, so we can ignore it
        // wres = GetError();
      }
      */
    }
    {
      DWORD prevSuspendCount = ResumeThread(h);
      /* ResumeThread() returns:
         0 : was_not_suspended
         1 : was_resumed
        -1 : error
      */
      if (prevSuspendCount == (DWORD)-1)
        wres = GetError();
    }
  }

  /* maybe we must use errno here, but probably GetLastError() is also OK. */
  return wres;

  #endif
}


static WRes Event_Create(CEvent *p, BOOL manualReset, int signaled)
{
  *p = CreateEvent(NULL, manualReset, (signaled ? TRUE : FALSE), NULL);
  return HandleToWRes(*p);
}

WRes Event_Set(CEvent *p) { return BOOLToWRes(SetEvent(*p)); }
WRes Event_Reset(CEvent *p) { return BOOLToWRes(ResetEvent(*p)); }

WRes ManualResetEvent_Create(CManualResetEvent *p, int signaled) { return Event_Create(p, TRUE, signaled); }
WRes AutoResetEvent_Create(CAutoResetEvent *p, int signaled) { return Event_Create(p, FALSE, signaled); }
WRes ManualResetEvent_CreateNotSignaled(CManualResetEvent *p) { return ManualResetEvent_Create(p, 0); }
WRes AutoResetEvent_CreateNotSignaled(CAutoResetEvent *p) { return AutoResetEvent_Create(p, 0); }


WRes Semaphore_Create(CSemaphore *p, UInt32 initCount, UInt32 maxCount)
{
  // negative ((LONG)maxCount) is not supported in WIN32::CreateSemaphore()
  *p = CreateSemaphore(NULL, (LONG)initCount, (LONG)maxCount, NULL);
  return HandleToWRes(*p);
}

WRes Semaphore_OptCreateInit(CSemaphore *p, UInt32 initCount, UInt32 maxCount)
{
  // if (Semaphore_IsCreated(p))
  {
    WRes wres = Semaphore_Close(p);
    if (wres != 0)
      return wres;
  }
  return Semaphore_Create(p, initCount, maxCount);
}

static WRes Semaphore_Release(CSemaphore *p, LONG releaseCount, LONG *previousCount)
  { return BOOLToWRes(ReleaseSemaphore(*p, releaseCount, previousCount)); }
WRes Semaphore_ReleaseN(CSemaphore *p, UInt32 num)
  { return Semaphore_Release(p, (LONG)num, NULL); }
WRes Semaphore_Release1(CSemaphore *p) { return Semaphore_ReleaseN(p, 1); }

WRes CriticalSection_Init(CCriticalSection *p)
{
  /* InitializeCriticalSection() can raise exception:
     Windows XP, 2003 : can raise a STATUS_NO_MEMORY exception
     Windows Vista+   : no exceptions */
  #ifdef _MSC_VER
  #ifdef __clang__
    #pragma GCC diagnostic ignored "-Wlanguage-extension-token"
  #endif
  __try
  #endif
  {
    InitializeCriticalSection(p);
    /* InitializeCriticalSectionAndSpinCount(p, 0); */
  }
  #ifdef _MSC_VER
  __except (EXCEPTION_EXECUTE_HANDLER) { return ERROR_NOT_ENOUGH_MEMORY; }
  #endif
  return 0;
}




#else // _WIN32

// ---------- POSIX ----------

#ifndef __APPLE__
#ifndef Z7_AFFINITY_DISABLE
// _GNU_SOURCE can be required for pthread_setaffinity_np() / CPU_ZERO / CPU_SET
// clang < 3.6       : unknown warning group '-Wreserved-id-macro'
// clang 3.6 - 12.01 : gives warning "macro name is a reserved identifier"
// clang >= 13       : do not give warning
#if !defined(_GNU_SOURCE)
  #if defined(__clang__) && (__clang_major__ >= 4) && (__clang_major__ <= 12)
    #pragma GCC diagnostic ignored "-Wreserved-id-macro"
  #endif
#define _GNU_SOURCE
#endif // !defined(_GNU_SOURCE)
#endif // Z7_AFFINITY_DISABLE
#endif // __APPLE__

#include "Threads.h"

#include <errno.h>
#include <stdlib.h>
#include <string.h>
#ifdef Z7_AFFINITY_SUPPORTED
// #include <sched.h>
#endif


// #include <stdio.h>
// #define PRF(p) p
#define PRF(p)
#define Print(s) PRF(printf("\n%s\n", s);)

WRes Thread_Create_With_CpuSet(CThread *p, THREAD_FUNC_TYPE func, LPVOID param, const CCpuSet *cpuSet)
{
  // new thread in Posix probably inherits affinity from parrent thread
  Print("Thread_Create_With_CpuSet")

  pthread_attr_t attr;
  int ret;
  // int ret2;

  p->_created = 0;

  RINOK(pthread_attr_init(&attr))

  ret = pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);

  if (!ret)
  {
    if (cpuSet)
    {
      #ifdef Z7_AFFINITY_SUPPORTED
      
      /*
      printf("\n affinity :");
      unsigned i;
      for (i = 0; i < sizeof(*cpuSet) && i < 8; i++)
      {
        Byte b = *((const Byte *)cpuSet + i);
        char temp[32];
        #define GET_HEX_CHAR(t) ((char)(((t < 10) ? ('0' + t) : ('A' + (t - 10)))))
        temp[0] = GET_HEX_CHAR((b & 0xF));
        temp[1] = GET_HEX_CHAR((b >> 4));
        // temp[0] = GET_HEX_CHAR((b >> 4));  // big-endian
        // temp[1] = GET_HEX_CHAR((b & 0xF));  // big-endian
        temp[2] = 0;
        printf("%s", temp);
      }
      printf("\n");
      */

      // ret2 =
      pthread_attr_setaffinity_np(&attr, sizeof(*cpuSet), cpuSet);
      // if (ret2) ret = ret2;
      #endif
    }
    
    ret = pthread_create(&p->_tid, &attr, func, param);
    
    if (!ret)
    {
      p->_created = 1;
      /*
      if (cpuSet)
      {
        // ret2 =
        pthread_setaffinity_np(p->_tid, sizeof(*cpuSet), cpuSet);
        // if (ret2) ret = ret2;
      }
      */
    }
  }
  // ret2 =
  pthread_attr_destroy(&attr);
  // if (ret2 != 0) ret = ret2;
  return ret;
}


WRes Thread_Create(CThread *p, THREAD_FUNC_TYPE func, LPVOID param)
{
  return Thread_Create_With_CpuSet(p, func, param, NULL);
}


WRes Thread_Create_With_Affinity(CThread *p, THREAD_FUNC_TYPE func, LPVOID param, CAffinityMask affinity)
{
  Print("Thread_Create_WithAffinity")
  CCpuSet cs;
  unsigned i;
  CpuSet_Zero(&cs);
  for (i = 0; i < sizeof(affinity) * 8; i++)
  {
    if (affinity == 0)
      break;
    if (affinity & 1)
    {
      CpuSet_Set(&cs, i);
    }
    affinity >>= 1;
  }
  return Thread_Create_With_CpuSet(p, func, param, &cs);
}


WRes Thread_Close(CThread *p)
{
  // Print("Thread_Close")
  int ret;
  if (!p->_created)
    return 0;
    
  ret = pthread_detach(p->_tid);
  p->_tid = 0;
  p->_created = 0;
  return ret;
}


WRes Thread_Wait_Close(CThread *p)
{
  // Print("Thread_Wait_Close")
  void *thread_return;
  int ret;
  if (!p->_created)
    return EINVAL;

  ret = pthread_join(p->_tid, &thread_return);
  // probably we can't use that (_tid) after pthread_join(), so we close thread here
  p->_created = 0;
  p->_tid = 0;
  return ret;
}



static WRes Event_Create(CEvent *p, int manualReset, int signaled)
{
  RINOK(pthread_mutex_init(&p->_mutex, NULL))
  RINOK(pthread_cond_init(&p->_cond, NULL))
  p->_manual_reset = manualReset;
  p->_state = (signaled ? True : False);
  p->_created = 1;
  return 0;
}

WRes ManualResetEvent_Create(CManualResetEvent *p, int signaled)
  { return Event_Create(p, True, signaled); }
WRes ManualResetEvent_CreateNotSignaled(CManualResetEvent *p)
  { return ManualResetEvent_Create(p, 0); }
WRes AutoResetEvent_Create(CAutoResetEvent *p, int signaled)
  { return Event_Create(p, False, signaled); }
WRes AutoResetEvent_CreateNotSignaled(CAutoResetEvent *p)
  { return AutoResetEvent_Create(p, 0); }


WRes Event_Set(CEvent *p)
{
  RINOK(pthread_mutex_lock(&p->_mutex))
  p->_state = True;
  int res1 = pthread_cond_broadcast(&p->_cond);
  int res2 = pthread_mutex_unlock(&p->_mutex);
  return (res2 ? res2 : res1);
}

WRes Event_Reset(CEvent *p)
{
  RINOK(pthread_mutex_lock(&p->_mutex))
  p->_state = False;
  return pthread_mutex_unlock(&p->_mutex);
}
 
WRes Event_Wait(CEvent *p)
{
  RINOK(pthread_mutex_lock(&p->_mutex))
  while (p->_state == False)
  {
    // ETIMEDOUT
    // ret =
    pthread_cond_wait(&p->_cond, &p->_mutex);
    // if (ret != 0) break;
  }
  if (p->_manual_reset == False)
  {
    p->_state = False;
  }
  return pthread_mutex_unlock(&p->_mutex);
}

WRes Event_Close(CEvent *p)
{
  if (!p->_created)
    return 0;
  p->_created = 0;
  {
    int res1 = pthread_mutex_destroy(&p->_mutex);
    int res2 = pthread_cond_destroy(&p->_cond);
    return (res1 ? res1 : res2);
  }
}


WRes Semaphore_Create(CSemaphore *p, UInt32 initCount, UInt32 maxCount)
{
  if (initCount > maxCount || maxCount < 1)
    return EINVAL;
  RINOK(pthread_mutex_init(&p->_mutex, NULL))
  RINOK(pthread_cond_init(&p->_cond, NULL))
  p->_count = initCount;
  p->_maxCount = maxCount;
  p->_created = 1;
  return 0;
}


WRes Semaphore_OptCreateInit(CSemaphore *p, UInt32 initCount, UInt32 maxCount)
{
  if (Semaphore_IsCreated(p))
  {
    /*
    WRes wres = Semaphore_Close(p);
    if (wres != 0)
      return wres;
    */
    if (initCount > maxCount || maxCount < 1)
      return EINVAL;
    // return EINVAL; // for debug
    p->_count = initCount;
    p->_maxCount = maxCount;
    return 0;
  }
  return Semaphore_Create(p, initCount, maxCount);
}


WRes Semaphore_ReleaseN(CSemaphore *p, UInt32 releaseCount)
{
  UInt32 newCount;
  int ret;

  if (releaseCount < 1)
    return EINVAL;

  RINOK(pthread_mutex_lock(&p->_mutex))

  newCount = p->_count + releaseCount;
  if (newCount > p->_maxCount)
    ret = ERROR_TOO_MANY_POSTS; // EINVAL;
  else
  {
    p->_count = newCount;
    ret = pthread_cond_broadcast(&p->_cond);
  }
  RINOK(pthread_mutex_unlock(&p->_mutex))
  return ret;
}

WRes Semaphore_Wait(CSemaphore *p)
{
  RINOK(pthread_mutex_lock(&p->_mutex))
  while (p->_count < 1)
  {
    pthread_cond_wait(&p->_cond, &p->_mutex);
  }
  p->_count--;
  return pthread_mutex_unlock(&p->_mutex);
}

WRes Semaphore_Close(CSemaphore *p)
{
  if (!p->_created)
    return 0;
  p->_created = 0;
  {
    int res1 = pthread_mutex_destroy(&p->_mutex);
    int res2 = pthread_cond_destroy(&p->_cond);
    return (res1 ? res1 : res2);
  }
}



WRes CriticalSection_Init(CCriticalSection *p)
{
  // Print("CriticalSection_Init")
  if (!p)
    return EINTR;
  return pthread_mutex_init(&p->_mutex, NULL);
}

void CriticalSection_Enter(CCriticalSection *p)
{
  // Print("CriticalSection_Enter")
  if (p)
  {
    // int ret =
    pthread_mutex_lock(&p->_mutex);
  }
}

void CriticalSection_Leave(CCriticalSection *p)
{
  // Print("CriticalSection_Leave")
  if (p)
  {
    // int ret =
    pthread_mutex_unlock(&p->_mutex);
  }
}

void CriticalSection_Delete(CCriticalSection *p)
{
  // Print("CriticalSection_Delete")
  if (p)
  {
    // int ret =
    pthread_mutex_destroy(&p->_mutex);
  }
}

LONG InterlockedIncrement(LONG volatile *addend)
{
  // Print("InterlockedIncrement")
  #ifdef USE_HACK_UNSAFE_ATOMIC
    LONG val = *addend + 1;
    *addend = val;
    return val;
  #else

  #if defined(__clang__) && (__clang_major__ >= 8)
    #pragma GCC diagnostic ignored "-Watomic-implicit-seq-cst"
  #endif
    return __sync_add_and_fetch(addend, 1);
  #endif
}

#endif // _WIN32

WRes AutoResetEvent_OptCreate_And_Reset(CAutoResetEvent *p)
{
  if (Event_IsCreated(p))
    return Event_Reset(p);
  return AutoResetEvent_CreateNotSignaled(p);
}

#undef PRF
#undef Print
