/*
 * NT basis DLL
 *
 * This file contains the Rtl* API functions. These should be implementable.
 *
 * Copyright 1996-1998 Marcus Meissner
 *		  1999 Alex Korobka
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "windef.h"
#include "winerror.h"
#include "winternl.h"
#include "winreg.h"
#include "wine/unicode.h"
#include "wine/debug.h"

WINE_DEFAULT_DEBUG_CHANNEL(ntdll);


static RTL_CRITICAL_SECTION peb_lock = CRITICAL_SECTION_INIT("peb_lock");

/*
 *	resource functions
 */

/***********************************************************************
 *           RtlInitializeResource	(NTDLL.@)
 *
 * xxxResource() functions implement multiple-reader-single-writer lock.
 * The code is based on information published in WDJ January 1999 issue.
 */
void WINAPI RtlInitializeResource(LPRTL_RWLOCK rwl)
{
    if( rwl )
    {
	rwl->iNumberActive = 0;
	rwl->uExclusiveWaiters = 0;
	rwl->uSharedWaiters = 0;
	rwl->hOwningThreadId = 0;
	rwl->dwTimeoutBoost = 0; /* no info on this one, default value is 0 */
	RtlInitializeCriticalSection( &rwl->rtlCS );
        NtCreateSemaphore( &rwl->hExclusiveReleaseSemaphore, 0, NULL, 0, 65535 );
        NtCreateSemaphore( &rwl->hSharedReleaseSemaphore, 0, NULL, 0, 65535 );
    }
}


/***********************************************************************
 *           RtlDeleteResource		(NTDLL.@)
 */
void WINAPI RtlDeleteResource(LPRTL_RWLOCK rwl)
{
    if( rwl )
    {
	RtlEnterCriticalSection( &rwl->rtlCS );
	if( rwl->iNumberActive || rwl->uExclusiveWaiters || rwl->uSharedWaiters )
	    MESSAGE("Deleting active MRSW lock (%p), expect failure\n", rwl );
	rwl->hOwningThreadId = 0;
	rwl->uExclusiveWaiters = rwl->uSharedWaiters = 0;
	rwl->iNumberActive = 0;
	NtClose( rwl->hExclusiveReleaseSemaphore );
	NtClose( rwl->hSharedReleaseSemaphore );
	RtlLeaveCriticalSection( &rwl->rtlCS );
	RtlDeleteCriticalSection( &rwl->rtlCS );
    }
}


/***********************************************************************
 *          RtlAcquireResourceExclusive	(NTDLL.@)
 */
BYTE WINAPI RtlAcquireResourceExclusive(LPRTL_RWLOCK rwl, BYTE fWait)
{
    BYTE retVal = 0;
    if( !rwl ) return 0;

start:
    RtlEnterCriticalSection( &rwl->rtlCS );
    if( rwl->iNumberActive == 0 ) /* lock is free */
    {
	rwl->iNumberActive = -1;
	retVal = 1;
    }
    else if( rwl->iNumberActive < 0 ) /* exclusive lock in progress */
    {
	 if( rwl->hOwningThreadId == (HANDLE)GetCurrentThreadId() )
	 {
	     retVal = 1;
	     rwl->iNumberActive--;
	     goto done;
	 }
wait:
	 if( fWait )
	 {
	     rwl->uExclusiveWaiters++;

	     RtlLeaveCriticalSection( &rwl->rtlCS );
	     if( WaitForSingleObject( rwl->hExclusiveReleaseSemaphore, INFINITE ) == WAIT_FAILED )
		 goto done;
	     goto start; /* restart the acquisition to avoid deadlocks */
	 }
    }
    else  /* one or more shared locks are in progress */
	 if( fWait )
	     goto wait;

    if( retVal == 1 )
	rwl->hOwningThreadId = (HANDLE)GetCurrentThreadId();
done:
    RtlLeaveCriticalSection( &rwl->rtlCS );
    return retVal;
}

/***********************************************************************
 *          RtlAcquireResourceShared	(NTDLL.@)
 */
BYTE WINAPI RtlAcquireResourceShared(LPRTL_RWLOCK rwl, BYTE fWait)
{
    DWORD dwWait = WAIT_FAILED;
    BYTE retVal = 0;
    if( !rwl ) return 0;

start:
    RtlEnterCriticalSection( &rwl->rtlCS );
    if( rwl->iNumberActive < 0 )
    {
	if( rwl->hOwningThreadId == (HANDLE)GetCurrentThreadId() )
	{
	    rwl->iNumberActive--;
	    retVal = 1;
	    goto done;
	}

	if( fWait )
	{
	    rwl->uSharedWaiters++;
	    RtlLeaveCriticalSection( &rwl->rtlCS );
	    if( (dwWait = WaitForSingleObject( rwl->hSharedReleaseSemaphore, INFINITE )) == WAIT_FAILED )
		goto done;
	    goto start;
	}
    }
    else
    {
	if( dwWait != WAIT_OBJECT_0 ) /* otherwise RtlReleaseResource() has already done it */
	    rwl->iNumberActive++;
	retVal = 1;
    }
done:
    RtlLeaveCriticalSection( &rwl->rtlCS );
    return retVal;
}


/***********************************************************************
 *           RtlReleaseResource		(NTDLL.@)
 */
void WINAPI RtlReleaseResource(LPRTL_RWLOCK rwl)
{
    RtlEnterCriticalSection( &rwl->rtlCS );

    if( rwl->iNumberActive > 0 ) /* have one or more readers */
    {
	if( --rwl->iNumberActive == 0 )
	{
	    if( rwl->uExclusiveWaiters )
	    {
wake_exclusive:
		rwl->uExclusiveWaiters--;
		NtReleaseSemaphore( rwl->hExclusiveReleaseSemaphore, 1, NULL );
	    }
	}
    }
    else
    if( rwl->iNumberActive < 0 ) /* have a writer, possibly recursive */
    {
	if( ++rwl->iNumberActive == 0 )
	{
	    rwl->hOwningThreadId = 0;
	    if( rwl->uExclusiveWaiters )
		goto wake_exclusive;
	    else
		if( rwl->uSharedWaiters )
		{
		    UINT n = rwl->uSharedWaiters;
		    rwl->iNumberActive = rwl->uSharedWaiters; /* prevent new writers from joining until
							       * all queued readers have done their thing */
		    rwl->uSharedWaiters = 0;
		    NtReleaseSemaphore( rwl->hSharedReleaseSemaphore, n, NULL );
		}
	}
    }
    RtlLeaveCriticalSection( &rwl->rtlCS );
}


/***********************************************************************
 *           RtlDumpResource		(NTDLL.@)
 */
void WINAPI RtlDumpResource(LPRTL_RWLOCK rwl)
{
    if( rwl )
    {
	MESSAGE("RtlDumpResource(%p):\n\tactive count = %i\n\twaiting readers = %i\n\twaiting writers = %i\n",
		rwl, rwl->iNumberActive, rwl->uSharedWaiters, rwl->uExclusiveWaiters );
	if( rwl->iNumberActive )
	    MESSAGE("\towner thread = %p\n", rwl->hOwningThreadId );
    }
}

/*
 *	misc functions
 */

/******************************************************************************
 *	DbgPrint	[NTDLL.@]
 */
void WINAPIV DbgPrint(LPCSTR fmt, ...)
{
       char buf[512];
       va_list args;

       va_start(args, fmt);
       vsprintf(buf,fmt, args);
       va_end(args);

	MESSAGE("DbgPrint says: %s",buf);
	/* hmm, raise exception? */
}

/******************************************************************************
 *  RtlAcquirePebLock		[NTDLL.@]
 */
VOID WINAPI RtlAcquirePebLock(void)
{
    RtlEnterCriticalSection( &peb_lock );
}

/******************************************************************************
 *  RtlReleasePebLock		[NTDLL.@]
 */
VOID WINAPI RtlReleasePebLock(void)
{
    RtlLeaveCriticalSection( &peb_lock );
}

/******************************************************************************
 *  RtlIntegerToChar	[NTDLL.@]
 */
DWORD WINAPI RtlIntegerToChar(DWORD x1,DWORD x2,DWORD x3,DWORD x4) {
	FIXME("(0x%08lx,0x%08lx,0x%08lx,0x%08lx),stub!\n",x1,x2,x3,x4);
	return 0;
}
/******************************************************************************
 *  RtlSetEnvironmentVariable		[NTDLL.@]
 */
DWORD WINAPI RtlSetEnvironmentVariable(DWORD x1,PUNICODE_STRING key,PUNICODE_STRING val) {
	FIXME("(0x%08lx,%s,%s),stub!\n",x1,debugstr_w(key->Buffer),debugstr_w(val->Buffer));
	return 0;
}

/******************************************************************************
 *  RtlNewSecurityObject		[NTDLL.@]
 */
DWORD WINAPI RtlNewSecurityObject(DWORD x1,DWORD x2,DWORD x3,DWORD x4,DWORD x5,DWORD x6) {
	FIXME("(0x%08lx,0x%08lx,0x%08lx,0x%08lx,0x%08lx,0x%08lx),stub!\n",x1,x2,x3,x4,x5,x6);
	return 0;
}

/******************************************************************************
 *  RtlDeleteSecurityObject		[NTDLL.@]
 */
DWORD WINAPI RtlDeleteSecurityObject(DWORD x1) {
	FIXME("(0x%08lx),stub!\n",x1);
	return 0;
}

/**************************************************************************
 *                 RtlNormalizeProcessParams		[NTDLL.@]
 */
LPVOID WINAPI RtlNormalizeProcessParams(LPVOID x)
{
    FIXME("(%p), stub\n",x);
    return x;
}

/**************************************************************************
 *                 RtlGetNtProductType			[NTDLL.@]
 */
BOOLEAN WINAPI RtlGetNtProductType(LPDWORD type)
{
    FIXME("(%p): stub\n", type);
    *type=3; /* dunno. 1 for client, 3 for server? */
    return 1;
}

/**************************************************************************
 *                 _chkstk				[NTDLL.@]
 *
 * Glorified "enter xxxx".
 */
void WINAPI NTDLL_chkstk( CONTEXT86 *context )
{
    context->Esp -= context->Eax;
}

/**************************************************************************
 *                 _alloca_probe		        [NTDLL.@]
 *
 * Glorified "enter xxxx".
 */
void WINAPI NTDLL_alloca_probe( CONTEXT86 *context )
{
    context->Esp -= context->Eax;
}

/**************************************************************************
 *                 RtlDosPathNameToNtPathName_U		[NTDLL.@]
 *
 * szwDosPath: a fully qualified DOS path name
 * ntpath:     pointer to a UNICODE_STRING to hold the converted
 *              path name
 *
 * FIXME: Should we not allocate the ntpath buffer under some
 *         circumstances?
 *        Are the conversions static? (always prepend '\??\' ?)
 *        Not really sure about the last two arguments.
 */
BOOLEAN  WINAPI RtlDosPathNameToNtPathName_U(
	LPWSTR szwDosPath,PUNICODE_STRING ntpath,
	DWORD x2,DWORD x3)
{
    ULONG length;
    UNICODE_STRING pathprefix;
    WCHAR szPrefix[] = { '\\', '?', '?', '\\', 0 };

    FIXME("(%s,%p,%08lx,%08lx) partial stub\n",
        debugstr_w(szwDosPath),ntpath,x2,x3);

    if ( !szwDosPath )
        return FALSE;

    if ( !szwDosPath[0] )
        return FALSE;
 
    if ( szwDosPath[1]!= ':' )
        return FALSE;

    length = strlenW(szwDosPath) * sizeof (WCHAR) + sizeof szPrefix;
 
    ntpath->Buffer = RtlAllocateHeap(GetProcessHeap(), 0, length);
    ntpath->Length = 0;
    ntpath->MaximumLength = length;

    if ( !ntpath->Buffer )
        return FALSE;

    RtlInitUnicodeString( &pathprefix, szPrefix );
    RtlCopyUnicodeString( ntpath, &pathprefix );
    RtlAppendUnicodeToString( ntpath, szwDosPath );

    return TRUE;
}


/******************************************************************************
 *  RtlCreateEnvironment		[NTDLL.@]
 */
DWORD WINAPI RtlCreateEnvironment(DWORD x1,DWORD x2) {
	FIXME("(0x%08lx,0x%08lx),stub!\n",x1,x2);
	return 0;
}


/******************************************************************************
 *  RtlDestroyEnvironment		[NTDLL.@]
 */
DWORD WINAPI RtlDestroyEnvironment(DWORD x) {
	FIXME("(0x%08lx),stub!\n",x);
	return 0;
}

/******************************************************************************
 *  RtlQueryEnvironmentVariable_U		[NTDLL.@]
 */
DWORD WINAPI RtlQueryEnvironmentVariable_U(DWORD x1,PUNICODE_STRING key,PUNICODE_STRING val) {
	FIXME("(0x%08lx,%s,%p),stub!\n",x1,debugstr_w(key->Buffer),val);
	return 0;
}
/******************************************************************************
 *  RtlInitializeGenericTable		[NTDLL.@]
 */
DWORD WINAPI RtlInitializeGenericTable(void)
{
	FIXME("\n");
	return 0;
}

/******************************************************************************
 *  RtlCopyMemory   [NTDLL]
 *
 */
#undef RtlCopyMemory
VOID WINAPI RtlCopyMemory( VOID *Destination, CONST VOID *Source, SIZE_T Length )
{
    memcpy(Destination, Source, Length);
}

/******************************************************************************
 *  RtlMoveMemory   [NTDLL.@]
 */
#undef RtlMoveMemory
VOID WINAPI RtlMoveMemory( VOID *Destination, CONST VOID *Source, SIZE_T Length )
{
    memmove(Destination, Source, Length);
}

/******************************************************************************
 *  RtlFillMemory   [NTDLL.@]
 */
#undef RtlFillMemory
VOID WINAPI RtlFillMemory( VOID *Destination, SIZE_T Length, BYTE Fill )
{
    memset(Destination, Fill, Length);
}

/******************************************************************************
 *  RtlZeroMemory   [NTDLL.@]
 */
#undef RtlZeroMemory
VOID WINAPI RtlZeroMemory( VOID *Destination, SIZE_T Length )
{
    memset(Destination, 0, Length);
}

/******************************************************************************
 *  RtlCompareMemory   [NTDLL.@]
 */
SIZE_T WINAPI RtlCompareMemory( const VOID *Source1, const VOID *Source2, SIZE_T Length)
{
    int i;
    for(i=0; (i<Length) && (((LPBYTE)Source1)[i]==((LPBYTE)Source2)[i]); i++);
    return i;
}

/******************************************************************************
 *  RtlAssert                           [NTDLL.@]
 *
 * Not implemented in non-debug versions.
 */
void WINAPI RtlAssert(LPVOID x1,LPVOID x2,DWORD x3, DWORD x4)
{
	FIXME("(%p,%p,0x%08lx,0x%08lx),stub\n",x1,x2,x3,x4);
}

/******************************************************************************
 *  RtlGetNtVersionNumbers       [NTDLL.@]
 *
 * Introduced in Windows XP (NT5.1)
 */
void WINAPI RtlGetNtVersionNumbers(LPDWORD major, LPDWORD minor, LPDWORD build)
{
	OSVERSIONINFOEXW versionInfo;
	versionInfo.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEXW);
	GetVersionExW((OSVERSIONINFOW*)&versionInfo);

	if (major)
	{
		*major = versionInfo.dwMajorVersion;
	}

	if (minor)
	{
		*minor = versionInfo.dwMinorVersion;
	}

	if (build)
	{
		/* FIXME: Does anybody know the real formula? */
		*build = (0xF0000000 | versionInfo.dwBuildNumber);
	}
}

/*************************************************************************
 * RtlFillMemoryUlong   [NTDLL.@]
 *
 * Fill memory with a 32 bit (dword) value.
 *
 * PARAMS
 *  lpDest  [I] Bitmap pointer
 *  ulCount [I] Number of dwords to write
 *  ulValue [I] Value to fill with
 *
 * RETURNS
 *  Nothing.
 */
VOID WINAPI RtlFillMemoryUlong(ULONG* lpDest, ULONG ulCount, ULONG ulValue)
{
  TRACE("(%p,%ld,%ld)\n", lpDest, ulCount, ulValue);

  while(ulCount--)
    *lpDest++ = ulValue;
}

/*************************************************************************
 * RtlGetLongestNtPathLength    [NTDLL.@]
 *
 * Get the longest allowed path length
 *
 * PARAMS
 *  None.
 *
 * RETURNS
 *  The longest allowed path length (277 characters under Win2k).
 */
DWORD WINAPI RtlGetLongestNtPathLength(void)
{
  TRACE("()\n");
  return 277;
}