reactos/subsys/win32k/eng/handle.c

   1 /*
   2  * COPYRIGHT:         See COPYING in the top level directory
   3  * PROJECT:           ReactOS kernel
   4  * PURPOSE:           Manage GDI Handles
   5  * FILE:              subsys/win32k/eng/handle.c
   6  * PROGRAMER:         Jason Filby
   7  * REVISION HISTORY:
   8  *                 29/8/1999: Created
   9  */
  10
  11 #include <ddk/winddi.h>
  12 #include "handle.h"
  13
  14 #define NDEBUG
  15 #include <win32k/debug1.h>
  16
  17 static int LastHandle = MAX_GDI_HANDLES;
  18
  19 ULONG CreateGDIHandle(ULONG InternalSize, ULONG UserSize)
  20 {
  21   ULONG size;
  22   PENGOBJ pObj;
  23   int i;
  24
  25   //size = sizeof( ENGOBJ ) + InternalSize + UserSize;
  26   size = InternalSize;          //internal size includes header and user portions
  27   pObj = EngAllocMem( FL_ZERO_MEMORY, size, 0 );
  28
  29   if( !pObj )
  30         return 0;
  31
  32   pObj->InternalSize = InternalSize;
  33   pObj->UserSize = UserSize;
  34
  35   for( i = (MAX_GDI_HANDLES - 1 <= LastHandle ? 1 : LastHandle + 1); i != LastHandle;
  36        i = (MAX_GDI_HANDLES - 1 <= i ? 1 : i + 1) ){
  37         if( GDIHandles[ i ].pEngObj == NULL ){
  38                 pObj->hObj = i;
  39                 GDIHandles[ i ].pEngObj = pObj;
  40                 DPRINT("CreateGDIHandle: obj: %x, handle: %d, usersize: %d\n", pObj, i, UserSize );
  41                 LastHandle = i;
  42                 return i;
  43         }
  44   }
  45   DPRINT1("CreateGDIHandle: Out of available handles!!!\n");
  46   EngFreeMem( pObj );
  47   return 0;
  48 }
  49
  50 VOID FreeGDIHandle(ULONG Handle)
  51 {
  52   if( Handle == 0 || Handle >= MAX_GDI_HANDLES ){
  53         DPRINT1("FreeGDIHandle: invalid handle!!!!\n");
  54         return;
  55   }
  56   DPRINT("FreeGDIHandle: handle: %d\n", Handle);
  57   EngFreeMem( GDIHandles[Handle].pEngObj );
  58   GDIHandles[Handle].pEngObj = NULL;
  59 }
  60
  61 PVOID AccessInternalObject(ULONG Handle)
  62 {
  63   PENGOBJ pEngObj;
  64
  65   if( Handle == 0 || Handle >= MAX_GDI_HANDLES ){
  66         DPRINT1("AccessInternalObject: invalid handle: %d!!!!\n", Handle);
  67         return NULL;
  68   }
  69
  70   pEngObj = GDIHandles[Handle].pEngObj;
  71   return (PVOID)pEngObj;
  72 }
  73
  74 PVOID AccessUserObject(ULONG Handle)
  75 {
  76   PENGOBJ pEngObj;
  77
  78   if( Handle == 0 || Handle >= MAX_GDI_HANDLES ){
  79         DPRINT1("AccessUserObject: invalid handle: %d!!!!\n", Handle);
  80         return NULL;
  81   }
  82
  83   pEngObj = GDIHandles[Handle].pEngObj;
  84   return (PVOID)( (PCHAR)pEngObj + sizeof( ENGOBJ ) );
  85 }
  86
  87 ULONG AccessHandleFromUserObject(PVOID UserObject)
  88 {
  89   PENGOBJ pEngObj;
  90   ULONG Handle;
  91
  92   if( !UserObject )
  93         return INVALID_HANDLE;
  94
  95   pEngObj = (PENGOBJ)((PCHAR) UserObject - sizeof( ENGOBJ ));
  96   Handle = pEngObj->hObj;
  97
  98   if( Handle == 0 || Handle >= MAX_GDI_HANDLES ){
  99         DPRINT1("AccessHandleFromUserObject: inv handle: %d, obj: %x!!!!\n", Handle, pEngObj);
 100         return INVALID_HANDLE;
 101   }
 102   return Handle;
 103 }
 104
 105 PVOID AccessInternalObjectFromUserObject(PVOID UserObject)
 106 {
 107
 108   return AccessInternalObject( AccessHandleFromUserObject( UserObject ) );
 109 }
 110
 111 VOID InitEngHandleTable( void )
 112 {
 113         ULONG i;
 114         for( i=1; i < MAX_GDI_HANDLES; i++ ){
 115                 GDIHandles[ i ].pEngObj = NULL;
 116         }
 117 }