#ifndef _RX_OS_SEM_H_
#define _RX_OS_SEM_H_

#include "rx_cc_macro.h"
#include "rx_assert.h"
#include <limits.h>

#if RX_OS_POSIX
#include <pthread.h>
#include <semaphore.h>
#include <memory.h>
#include <errno.h>
//-lpthread
#endif


namespace rx
{
	#if RX_OS_POSIX
	//---------------------------------------------------------
	//对SEM旗标/信号量进行对象化功能封装
	class semp_t
	{
		sem_t   m_handle;
	public:
		//-----------------------------------------------------
		semp_t() { memset(&m_handle, 0, sizeof(m_handle)); }
		semp_t(uint32_t init_value) { memset(&m_handle, 0, sizeof(m_handle)); init(init_value); }
		~semp_t() { uninit(); }
		//-----------------------------------------------------
		//初始化旗标,告知初始值
		bool init(uint32_t init_value = 0) { return 0 == sem_init(&m_handle, 0, init_value); }
		//-----------------------------------------------------
		//解除旗标初始化
		void uninit() { sem_destroy(&m_handle); }
		//-----------------------------------------------------
		//获取计数,可进行超时等待(默认无限等待)
		//返回值:是否正确取得了计数
		bool take(int wait_ms = -1)
		{
			if (wait_ms == 0)
				return 0 == sem_trywait(&m_handle);
			else if (wait_ms == -1)
				return 0 == sem_wait(&m_handle);
			else
			{
				//使用原生超时等待容易被系统时间的调整干扰致死,这里使用多次循环模拟(不太精准)
				for (int i = 0; i < wait_ms; ++i)
				{
					if (0 == sem_trywait(&m_handle))
						return true;
					else if (EINVAL == errno)
						return false;
					usleep(1000);
				}
				return false;
			}
		}
		//-----------------------------------------------------
		//提交计数,可解除对方的等待
		bool post()
		{
			return 0 == sem_post(&m_handle);
		}
	};
	#elif RX_IS_OS_WIN
	//---------------------------------------------------------
	//对SEM旗标/信号量进行对象化功能封装
	class semp_t
	{
		HANDLE      m_handle;
	public:
		//-----------------------------------------------------
		semp_t() :m_handle(NULL) {}
		semp_t(uint32_t init_value) :m_handle(NULL) { init(init_value); }
		~semp_t() { uninit(); }
		//-----------------------------------------------------
		//初始化旗标,告知初始值
		bool init(uint32_t init_value = 0)
		{
			rx_assert(m_handle == NULL);
			m_handle = CreateSemaphore(NULL, (long)init_value, LONG_MAX, NULL);
			return NULL != m_handle;
		}
		//-----------------------------------------------------
		//解除旗标初始化
		void uninit() { CloseHandle(m_handle); m_handle = NULL; }
		//-----------------------------------------------------
		//获取计数,可进行超时等待(默认无限等待)
		//返回值:是否正确取得了计数
		bool take(int wait_ms = -1)
		{
			if (wait_ms == 0)
				return WAIT_OBJECT_0 == WaitForSingleObject(m_handle, 0);
			else if (wait_ms == -1)
				return WAIT_OBJECT_0 == WaitForSingleObject(m_handle, INFINITE);
			else
				return WAIT_OBJECT_0 == WaitForSingleObject(m_handle, wait_ms);
		}
		//-----------------------------------------------------
		//提交计数,可解除对方的等待
		bool post()
		{
			return !!ReleaseSemaphore(m_handle, 1, NULL);
		}
	};
	#endif
}
#endif // _HX_SEM_H_