/*------
 * Module:			xalibname.c
 *
 * Description:
 *		This module gets the (path) name of xalib.
 *
 *-------
 */

#ifdef	_HANDLE_ENLIST_IN_DTC_

#ifndef	_WIN32_WINNT
#define	_WIN32_WINNT	0x0400
#endif	/* _WIN32_WINNT */

#define	WIN32_LEAN_AND_MEAN

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

extern HMODULE	s_hModule;

static char	xalibpath[_MAX_PATH] = "";
static char	xalibname[_MAX_FNAME] = "";

static const char * const PGMFILES = "Program Files";
static const char * const PGMFILESX86 = "Program Files (x86)";

typedef BOOL (WINAPI *LPFN_ISWOW64PROCESS) (HANDLE, PBOOL);
LPFN_ISWOW64PROCESS fnIsWow64Process;

BOOL IsWow64()
{
	static BOOL bCalled = FALSE;
	static BOOL bIsWow64 = FALSE;

	if (bCalled)
		return bIsWow64;
	fnIsWow64Process = (LPFN_ISWOW64PROCESS) GetProcAddress(
		GetModuleHandle("kernel32"), "IsWow64Process");

	if (NULL != fnIsWow64Process)
	{
		if (!fnIsWow64Process(GetCurrentProcess(), &bIsWow64))
		{
			//handle error
		}
	}
	bCalled = TRUE;
	return bIsWow64;
}

const char *GetXaLibName(void)
{
	char	dllpath[_MAX_PATH], drive[_MAX_DRIVE], dir[_MAX_DIR],
		fname[_MAX_FNAME], ext[_MAX_EXT];
	if (!xalibpath[0])
	{
		size_t	pgmflen = strlen(PGMFILESX86);
		char	*ptr;

		GetModuleFileName(s_hModule, dllpath, sizeof(dllpath));
		/* In Windows XP SP2, the dllname should be specified */
		/* instead of the dll path name, because it looks up */
		/* the HKLM\Microfost\MSDTC\XADLL\(dllname) registry */
		/* entry for security reason. */
		_splitpath(dllpath, drive, dir, fname, ext);
		strncpy(xalibname, "pgxalib.dll", sizeof(xalibname));
		if (IsWow64())
		{
			if ('\\' == *dir &&
		    	    0 == _strnicmp(dir + 1, PGMFILESX86, pgmflen))
			{
				ptr = dir + 1 + pgmflen;
				if ('\\' == *ptr)
					_snprintf(xalibpath, sizeof(xalibpath), "%s\\%s%s%s", drive, PGMFILES, ptr, xalibname);
			}
		}
		else 	
			_snprintf(xalibpath, sizeof(xalibpath), "%s%s%s", drive, dir, xalibname);
	}
	return xalibname;
}

const char *GetXaLibPath(void)
{
	GetXaLibName();
	return xalibpath;
}
#endif /* _HANDLE_ENLIST_IN_DTC_ */