MdePkg/Library/BaseMemoryLib/ScanMem16Wrapper.c

   1 /** @file
   2   ScanMem16() implementation.
   3
   4   Copyright (c) 2006, Intel Corporation<BR>
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13   Module Name:  ScanMem16Wrapper.c
  14
  15   The following BaseMemoryLib instances share the same version of this file:
  16
  17     BaseMemoryLib
  18     BaseMemoryLibMmx
  19     BaseMemoryLibSse2
  20     BaseMemoryLibRepStr
  21     PeiMemoryLib
  22     DxeMemoryLib
  23
  24 **/
  25
  26 #include "MemLibInternals.h"
  27
  28 /**
  29   Scans a target buffer for a 16-bit value, and returns a pointer to the matching 16-bit value
  30   in the target buffer.
  31
  32   This function searches target the buffer specified by Buffer and Length from the lowest
  33   address to the highest address for a 16-bit value that matches Value.  If a match is found,
  34   then a pointer to the matching byte in the target buffer is returned.  If no match is found,
  35   then NULL is returned.  If Length is 0, then NULL is returned.
  36   If Length > 0 and Buffer is NULL, then ASSERT().
  37   If Buffer is not aligned on a 16-bit boundary, then ASSERT().
  38   If Length is not aligned on a 16-bit boundary, then ASSERT().
  39   If Length is greater than (MAX_ADDRESS ? Buffer + 1), then ASSERT().
  40
  41   @param  Buffer      Pointer to the target buffer to scan.
  42   @param  Length      Number of bytes in Buffer to scan.
  43   @param  Value       Value to search for in the target buffer.
  44
  45   @return A pointer to the matching byte in the target buffer or NULL otherwise.
  46
  47 **/
  48 VOID *
  49 EFIAPI
  50 ScanMem16 (
  51   IN CONST VOID  *Buffer,
  52   IN UINTN       Length,
  53   IN UINT16      Value
  54   )
  55 {
  56   if (Length == 0) {
  57     return NULL;
  58   }
  59
  60   ASSERT (Buffer != NULL);
  61   ASSERT (((UINTN)Buffer & (sizeof (Value) - 1)) == 0);
  62   ASSERT ((Length - 1) <= (MAX_ADDRESS - (UINTN)Buffer));
  63   ASSERT ((Length & (sizeof (Value) - 1)) == 0);
  64
  65   return (VOID*)InternalMemScanMem16 (Buffer, Length / sizeof (Value), Value);
  66 }