/** * WinPR: Windows Portable Runtime * Countdown Event * * Copyright 2012 Marc-Andre Moreau * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #ifdef HAVE_UNISTD_H #include #endif #include #include /** * C equivalent of the C# CountdownEvent Class * http://msdn.microsoft.com/en-us/library/dd235708/ */ /** * Properties */ /** * Gets the number of remaining signals required to set the event. */ DWORD CountdownEvent_CurrentCount(wCountdownEvent* countdown) { return countdown->count; } /** * Gets the numbers of signals initially required to set the event. */ DWORD CountdownEvent_InitialCount(wCountdownEvent* countdown) { return countdown->initialCount; } /** * Determines whether the event is set. */ BOOL CountdownEvent_IsSet(wCountdownEvent* countdown) { BOOL status = FALSE; if (WaitForSingleObject(countdown->event, 0) == WAIT_OBJECT_0) status = TRUE; return status; } /** * Gets a WaitHandle that is used to wait for the event to be set. */ HANDLE CountdownEvent_WaitHandle(wCountdownEvent* countdown) { return countdown->event; } /** * Methods */ /** * Increments the CountdownEvent's current count by a specified value. */ void CountdownEvent_AddCount(wCountdownEvent* countdown, DWORD signalCount) { EnterCriticalSection(&countdown->lock); countdown->count += signalCount; if (countdown->count > 0) ResetEvent(countdown->event); LeaveCriticalSection(&countdown->lock); } /** * Registers multiple signals with the CountdownEvent, decrementing the value of CurrentCount by the specified amount. */ BOOL CountdownEvent_Signal(wCountdownEvent* countdown, DWORD signalCount) { BOOL status; BOOL newStatus; BOOL oldStatus; status = newStatus = oldStatus = FALSE; 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)) { SetEvent(countdown->event); status = TRUE; } LeaveCriticalSection(&countdown->lock); return status; } /** * Resets the InitialCount property to a specified value. */ void CountdownEvent_Reset(wCountdownEvent* countdown, DWORD count) { countdown->initialCount = count; } /** * Construction, Destruction */ wCountdownEvent* CountdownEvent_New(DWORD initialCount) { wCountdownEvent* countdown = NULL; countdown = (wCountdownEvent*) malloc(sizeof(wCountdownEvent)); if (countdown) { countdown->count = initialCount; countdown->initialCount = initialCount; InitializeCriticalSectionAndSpinCount(&countdown->lock, 4000); countdown->event = CreateEvent(NULL, TRUE, FALSE, NULL); if (countdown->count == 0) SetEvent(countdown->event); } return countdown; } void CountdownEvent_Free(wCountdownEvent* countdown) { DeleteCriticalSection(&countdown->lock); CloseHandle(countdown->event); free(countdown); }