reactos/win32ss/user/ntuser/useratom.c

   1 /*
   2  * COPYRIGHT:        See COPYING in the top level directory
   3  * PROJECT:          ReactOS kernel
   4  * PURPOSE:          User Atom helper routines
   5  * FILE:             subsys/win32k/ntuser/useratom.c
   6  * PROGRAMER:        Filip Navara <xnavara@volny.cz>
   7  */
   8
   9 #include <win32k.h>
  10 DBG_DEFAULT_CHANNEL(UserMisc);
  11
  12 RTL_ATOM FASTCALL
  13 IntAddAtom(LPWSTR AtomName)
  14 {
  15    NTSTATUS Status = STATUS_SUCCESS;
  16    PTHREADINFO pti;
  17    RTL_ATOM Atom;
  18
  19    pti = PsGetCurrentThreadWin32Thread();
  20    if (pti->rpdesk == NULL)
  21    {
  22       SetLastNtError(Status);
  23       return (RTL_ATOM)0;
  24    }
  25
  26    Status = RtlAddAtomToAtomTable(gAtomTable, AtomName, &Atom);
  27
  28    if (!NT_SUCCESS(Status))
  29    {
  30       SetLastNtError(Status);
  31       return (RTL_ATOM)0;
  32    }
  33    return Atom;
  34 }
  35
  36 ULONG FASTCALL
  37 IntGetAtomName(RTL_ATOM nAtom, LPWSTR lpBuffer, ULONG cjBufSize)
  38 {
  39    NTSTATUS Status = STATUS_SUCCESS;
  40    PTHREADINFO pti;
  41    ULONG Size = cjBufSize;
  42
  43    pti = PsGetCurrentThreadWin32Thread();
  44    if (pti->rpdesk == NULL)
  45    {
  46       SetLastNtError(Status);
  47       return 0;
  48    }
  49
  50    Status = RtlQueryAtomInAtomTable(gAtomTable, nAtom, NULL, NULL, lpBuffer, &Size);
  51
  52    if (!NT_SUCCESS(Status))
  53    {
  54       SetLastNtError(Status);
  55       return 0;
  56    }
  57
  58    return Size;
  59 }
  60
  61 RTL_ATOM FASTCALL
  62 IntAddGlobalAtom(LPWSTR lpBuffer, BOOL PinAtom)
  63 {
  64    RTL_ATOM Atom;
  65    NTSTATUS Status = STATUS_SUCCESS;
  66
  67    Status = RtlAddAtomToAtomTable(gAtomTable, lpBuffer, &Atom);
  68
  69    if (!NT_SUCCESS(Status))
  70    {
  71       ERR("Error init Global Atom.\n");
  72       return 0;
  73    }
  74
  75    if ( Atom && PinAtom ) RtlPinAtomInAtomTable(gAtomTable, Atom);
  76
  77    return Atom;
  78 }
  79
  80 /*!
  81  * \brief Returns the name of an atom.
  82  *
  83  * \param atom - The atom to be queried.
  84  * \param pustrName - Pointer to an initialized UNICODE_STRING that receives
  85  *                    the name of the atom. The function does not update the
  86                       Length member. The string is always NULL-terminated.
  87  *
  88  * \return The length of the name in characters, or 0 if the function fails.
  89  *
  90  * \note The function does not aquire any global lock, since synchronisation is
  91  *       handled by the RtlAtom function.
  92  */
  93 _Success_(return!=0)
  94 _At_(pustrName->Buffer, _Out_z_bytecap_post_bytecount_(pustrName->MaximumLength, return*2+2))
  95 ULONG
  96 APIENTRY
  97 NtUserGetAtomName(
  98     _In_ ATOM atom,
  99     _Inout_ PUNICODE_STRING pustrName)
 100 {
 101     WCHAR awcBuffer[256];
 102     ULONG cjLength;
 103
 104     /* Retrieve the atom name into a local buffer (max length is 255 chars) */
 105     cjLength = IntGetAtomName((RTL_ATOM)atom, awcBuffer, sizeof(awcBuffer));
 106     if (cjLength != 0)
 107     {
 108         _SEH2_TRY
 109         {
 110             /* Probe the unicode string and the buffer */
 111             ProbeForRead(pustrName, sizeof(*pustrName), 1);
 112             ProbeForWrite(pustrName->Buffer, pustrName->MaximumLength, 1);
 113
 114             /* Check if we have enough space to write the NULL termination */
 115             if (pustrName->MaximumLength >= sizeof(UNICODE_NULL))
 116             {
 117                 /* Limit the length to the buffer size */
 118                 cjLength = min(pustrName->MaximumLength - sizeof(UNICODE_NULL),
 119                                cjLength);
 120
 121                 /* Copy the string and NULL terminate it */
 122                 RtlCopyMemory(pustrName->Buffer, awcBuffer, cjLength);
 123                 pustrName->Buffer[cjLength / sizeof(WCHAR)] = L'\0';
 124             }
 125             else
 126             {
 127                 cjLength = 0;
 128             }
 129         }
 130         _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
 131         {
 132             /* On exception, set last error and fail */
 133             SetLastNtError(_SEH2_GetExceptionCode());
 134             cjLength = 0;
 135         }
 136         _SEH2_END
 137     }
 138
 139     /* Return the length in characters */
 140     return cjLength / sizeof(WCHAR);
 141 }
 142
 143 /* EOF */