CountdownEvent.c

 
#include <winpr/config.h>
#include <winpr/assert.h>
 
#include <winpr/crt.h>
 
#include <winpr/collections.h>
 
struct CountdownEvent
{
  size_t count;
  CRITICAL_SECTION lock;
  HANDLE event;
  size_t initialCount;
};
 
size_t CountdownEvent_CurrentCount(wCountdownEvent* countdown)
{
  WINPR_ASSERT(countdown);
  EnterCriticalSection(&countdown->lock);
  const size_t rc = countdown->count;
  LeaveCriticalSection(&countdown->lock);
  return rc;
}
 
size_t CountdownEvent_InitialCount(wCountdownEvent* countdown)
{
  WINPR_ASSERT(countdown);
  EnterCriticalSection(&countdown->lock);
  const size_t rc = countdown->initialCount;
  LeaveCriticalSection(&countdown->lock);
  return rc;
}
 
BOOL CountdownEvent_IsSet(wCountdownEvent* countdown)
{
  BOOL status = FALSE;
 
  WINPR_ASSERT(countdown);
  if (WaitForSingleObject(countdown->event, 0) == WAIT_OBJECT_0)
    status = TRUE;
 
  return status;
}
 
HANDLE CountdownEvent_WaitHandle(wCountdownEvent* countdown)
{
  WINPR_ASSERT(countdown);
  return countdown->event;
}
 
void CountdownEvent_AddCount(wCountdownEvent* countdown, size_t signalCount)
{
  WINPR_ASSERT(countdown);
  EnterCriticalSection(&countdown->lock);
 
  const BOOL signalSet = countdown->count == 0;
  countdown->count += signalCount;
 
  if (signalSet)
    (void)ResetEvent(countdown->event);
 
  LeaveCriticalSection(&countdown->lock);
}
 
BOOL CountdownEvent_Signal(wCountdownEvent* countdown, size_t signalCount)
{
  BOOL status = FALSE;
  BOOL newStatus = FALSE;
  BOOL oldStatus = FALSE;
 
  WINPR_ASSERT(countdown);
 
  EnterCriticalSection(&countdown->lock);
 
  if (WaitForSingleObject(countdown->event, 0) == WAIT_OBJECT_0)
    oldStatus = TRUE;
 
  if (signalCount <= countdown->count)
    countdown->count -= signalCount;
  else
    countdown->count = 0;
 
  if (countdown->count == 0)
    newStatus = TRUE;
 
  if (newStatus && (!oldStatus))
  {
    (void)SetEvent(countdown->event);
    status = TRUE;
  }
 
  LeaveCriticalSection(&countdown->lock);
 
  return status;
}
 
void CountdownEvent_Reset(wCountdownEvent* countdown, size_t count)
{
  WINPR_ASSERT(countdown);
  countdown->initialCount = count;
}
 
wCountdownEvent* CountdownEvent_New(size_t initialCount)
{
  wCountdownEvent* countdown = (wCountdownEvent*)calloc(1, sizeof(wCountdownEvent));
 
  if (!countdown)
    return NULL;
 
  countdown->count = initialCount;
  countdown->initialCount = initialCount;
 
  if (!InitializeCriticalSectionAndSpinCount(&countdown->lock, 4000))
    goto fail;
 
  countdown->event = CreateEvent(NULL, TRUE, FALSE, NULL);
  if (!countdown->event)
    goto fail;
 
  if (countdown->count == 0)
  {
    if (!SetEvent(countdown->event))
      goto fail;
  }
 
  return countdown;
 
fail:
  WINPR_PRAGMA_DIAG_PUSH
  WINPR_PRAGMA_DIAG_IGNORED_MISMATCHED_DEALLOC
  CountdownEvent_Free(countdown);
  WINPR_PRAGMA_DIAG_POP
  return NULL;
}
 
void CountdownEvent_Free(wCountdownEvent* countdown)
{
  if (!countdown)
    return;
 
  DeleteCriticalSection(&countdown->lock);
  (void)CloseHandle(countdown->event);
 
  free(countdown);
}