#include "WinUtil.h"
using namespace std;

SharedMemory::SharedMemory(const string& name)
{
    hMap=OpenFileMapping(FILE_MAP_ALL_ACCESS,FALSE,name.c_str());
    if(hMap!=NULL) pMem=MapViewOfFile(hMap,FILE_MAP_ALL_ACCESS,0,0,0);
    else pMem=nullptr;
}

SharedMemory::SharedMemory(const string& name,int size)
{
    hMap=CreateFileMapping(INVALID_HANDLE_VALUE,NULL,PAGE_READWRITE,0,size,name.c_str());
    if(hMap!=NULL) pMem=MapViewOfFile(hMap,FILE_MAP_ALL_ACCESS,0,0,0);
    else pMem=nullptr;
}

SharedMemory::~SharedMemory()
{
    if(pMem)
    {
        UnmapViewOfFile(pMem);
    }
    if(hMap!=NULL)
    {
        CloseHandle(hMap);
    }
}

bool SharedMemory::isReady() const
{
    return (hMap!=NULL);
}

void* SharedMemory::get()
{
    return pMem;
}


NamedMutex::NamedMutex(const string& name, bool create)
{
    if(create)
    {
        hmtx=CreateMutex(NULL,TRUE,name.c_str());
    }
    else
    {
        hmtx=OpenMutex(MUTEX_ALL_ACCESS,FALSE,name.c_str());
    }
    if(hmtx==NULL)
    {
        errcode=GetLastError();
    }
}

NamedMutex::~NamedMutex()
{
    if(hmtx!=NULL)
    {
        CloseHandle(hmtx);
    }
}

bool NamedMutex::isReady() const
{
    return (hmtx!=NULL);
}

DWORD NamedMutex::getError() const
{
    return errcode;
}

int NamedMutex::wait()
{
    return wait_for(INFINITE);
}

int NamedMutex::wait_for(int ms)
{
    DWORD ret=WaitForSingleObject(hmtx,ms);
    if(ret==WAIT_OBJECT_0)
    {
        return 1;
    }
    else if(ret==WAIT_TIMEOUT)
    {
        return 0;
    }
    else
    {
        // WAIT_ABANDONED
        // WAIT_FAILED
        errcode=GetLastError();
        return -1;
    }
}

void NamedMutex::release()
{
    ReleaseMutex(hmtx);
}