Deliver/include/Log4CPP/Common.Include/ErrorCodeToString.hpp

#pragma once

#include <string>

//#include "TmplBlockBuffer.tlh"
//#include "TmplBlockBuffer.tli"


//	通过调用 FormtMessage, 把 Win32 错误码转换成字符串
inline std::string ErrorCodeToString (DWORD errorCode)
{
	std::string rc;

	if (errorCode == 0)  errorCode = GetLastError ();

	std::string fs = std::to_string (errorCode);

	rc += "<Error Code=";
	rc += fs;
	rc += "> : ";

	const int nPreAlloc = 2048;

	//ECOM::Utility::TmplUniqueBuffer <char> errmsg;
//	auto pszBuffer = errmsg.GetBufferSetCount (nPreAlloc);
	std::string errmsg;
	errmsg.reserve (nPreAlloc);
	auto pszBuffer = errmsg.data ();

	auto len = ::FormatMessageA (FORMAT_MESSAGE_FROM_SYSTEM,
		NULL,
		errorCode, // GetLastError (),
		MAKELANGID (LANG_NEUTRAL, SUBLANG_DEFAULT),
		(LPTSTR) pszBuffer,
		nPreAlloc,
		NULL);

	rc.append (pszBuffer, len - 2); // -2 : 目的是删除尾部的回车/换行

	return std::move (rc);
}