test_semaphore.cpp

#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#include <stdlib.h>
#include <process.h>

///////////////////////////1//1///111111/! 
// crt_ begthrdex. cpp
// compile with: /MT

#define LOG_INFO(fmt, ...)   { printf(fmt"\n", ##__VA_ARGS__); fflush(stdout); }

HANDLE g_hSem = NULL;
unsigned g_Counter = 0;
const static int THREAD_COUNT = 64;

struct Arguments
{
	int counter;
	int seq;
};
Arguments g_arguments[THREAD_COUNT] = { 0 };

unsigned _stdcall SecondThreadFunc(void* pArguments)
{
	Arguments* pArg = (Arguments*)pArguments;
	pArg->counter++;
	unsigned tid = GetCurrentThreadId();

	HFILE hFile[1024] = { 0 };

	LOG_INFO("[%2d, %6d, %4d] step1, WaitForSingleobject, %p", pArg->seq, tid, pArg->counter, g_hSem);
	WaitForSingleObject(g_hSem, INFINITE);

	LOG_INFO("[%2d, %6d, %4d] setp2, Open", pArg->seq, tid, pArg->counter);
	for (int i = 0; i < sizeof(hFile) / sizeof(HFILE); i++) {
		OFSTRUCT ofstruct;
		hFile[i] = OpenFile("aaa.txt", &ofstruct, OF_READWRITE);
		g_Counter++;
	}
	Sleep(1);
	LOG_INFO("[%2d, %6d, %4d] setp3, release", pArg->seq, tid, pArg->counter);
	ReleaseSemaphore(g_hSem, 1, NULL);
	LOG_INFO("[%2d, %6d, %4d] setp4, closeHandle", pArg->seq, tid, pArg->counter);
	for (int i = 0; i < 1024; i++) {
		if (hFile[i]) {
			CloseHandle((HANDLE)hFile[i]);
		}
	}

	LOG_INFO("[%2d, %6d, %4d] setp5, finished", pArg->seq, tid, pArg->counter);

	_endthreadex(0);
	return 0;
}


int main(int argc, char* argv[])
{
	HANDLE hThread[THREAD_COUNT] = { 0 };
	unsigned threadID[THREAD_COUNT];
	g_hSem = CreateSemaphore(NULL, 0, THREAD_COUNT, _T("mySem"));

	LOG_INFO("main, Createing second thread ...");
	for (unsigned i = 0; i < THREAD_COUNT; i++) {
		g_arguments[i].seq = i;
		g_arguments[i].counter = 0;
		hThread[i] = (HANDLE)_beginthreadex(NULL, 0, &SecondThreadFunc, (unsigned*)&g_arguments[i], 0, &threadID[i]);
	}

	Sleep(3000);
	int release_count = 10;
	LOG_INFO("main, release %d", release_count);
	ReleaseSemaphore(g_hSem, release_count, NULL);


	WaitForMultipleObjects(THREAD_COUNT, hThread, TRUE, INFINITE);
	LOG_INFO("main, Counter should be 1000000; it is -> %d", g_Counter);

	for (int i = 0; i < THREAD_COUNT; i++) {
		if (hThread[i]) {
			CloseHandle(hThread[i]);
		}
	}

	if (g_hSem) {
		CloseHandle(g_hSem);
	}
	return 0;
}