/** @file
Architecture Independent Base Memory Library Implementation.
The following BaseMemoryLib instances contain the same copy of this file:
BaseMemoryLib
PeiMemoryLib
UefiMemoryLib
Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php.
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "MemLibInternals.h"
/**
Fills a target buffer with a 16-bit value, and returns the target buffer.
@param Buffer The pointer to the target buffer to fill.
@param Length The count of 16-bit value to fill.
@param Value The value with which to fill Length bytes of Buffer.
@return Buffer
**/
VOID *
EFIAPI
InternalMemSetMem16 (
OUT VOID *Buffer,
IN UINTN Length,
IN UINT16 Value
)
{
for (; Length != 0; Length--) {
((UINT16*)Buffer)[Length - 1] = Value;
}
return Buffer;
}
/**
Fills a target buffer with a 32-bit value, and returns the target buffer.
@param Buffer The pointer to the target buffer to fill.
@param Length The count of 32-bit value to fill.
@param Value The value with which to fill Length bytes of Buffer.
@return Buffer
**/
VOID *
EFIAPI
InternalMemSetMem32 (
OUT VOID *Buffer,
IN UINTN Length,
IN UINT32 Value
)
{
for (; Length != 0; Length--) {
((UINT32*)Buffer)[Length - 1] = Value;
}
return Buffer;
}
/**
Fills a target buffer with a 64-bit value, and returns the target buffer.
@param Buffer The pointer to the target buffer to fill.
@param Length The count of 64-bit value to fill.
@param Value The value with which to fill Length bytes of Buffer.
@return Buffer
**/
VOID *
EFIAPI
InternalMemSetMem64 (
OUT VOID *Buffer,
IN UINTN Length,
IN UINT64 Value
)
{
for (; Length != 0; Length--) {
((UINT64*)Buffer)[Length - 1] = Value;
}
return Buffer;
}
/**
Set Buffer to 0 for Size bytes.
@param Buffer Memory to set.
@param Length The number of bytes to set
@return Buffer
**/
VOID *
EFIAPI
InternalMemZeroMem (
OUT VOID *Buffer,
IN UINTN Length
)
{
return InternalMemSetMem (Buffer, Length, 0);
}
/**
Compares two memory buffers of a given length.
@param DestinationBuffer The first memory buffer
@param SourceBuffer The second memory buffer
@param Length The length of DestinationBuffer and SourceBuffer memory
regions to compare. Must be non-zero.
@return 0 All Length bytes of the two buffers are identical.
@retval Non-zero The first mismatched byte in SourceBuffer subtracted from the first
mismatched byte in DestinationBuffer.
**/
INTN
EFIAPI
InternalMemCompareMem (
IN CONST VOID *DestinationBuffer,
IN CONST VOID *SourceBuffer,
IN UINTN Length
)
{
while ((--Length != 0) &&
(*(INT8*)DestinationBuffer == *(INT8*)SourceBuffer)) {
DestinationBuffer = (INT8*)DestinationBuffer + 1;
SourceBuffer = (INT8*)SourceBuffer + 1;
}
return (INTN)*(UINT8*)DestinationBuffer - (INTN)*(UINT8*)SourceBuffer;
}
/**
Scans a target buffer for an 8-bit value, and returns a pointer to the
matching 8-bit value in the target buffer.
@param Buffer The pointer to the target buffer to scan.
@param Length The count of 8-bit value to scan. Must be non-zero.
@param Value The value to search for in the target buffer.
@return The pointer to the first occurrence or NULL if not found.
**/
CONST VOID *
EFIAPI
InternalMemScanMem8 (
IN CONST VOID *Buffer,
IN UINTN Length,
IN UINT8 Value
)
{
CONST UINT8 *Pointer;
Pointer = (CONST UINT8*)Buffer;
do {
if (*(Pointer++) == Value) {
return --Pointer;
}
} while (--Length != 0);
return NULL;
}
/**
Scans a target buffer for a 16-bit value, and returns a pointer to the
matching 16-bit value in the target buffer.
@param Buffer The pointer to the target buffer to scan.
@param Length The count of 16-bit value to scan. Must be non-zero.
@param Value The value to search for in the target buffer.
@return The pointer to the first occurrence or NULL if not found.
**/
CONST VOID *
EFIAPI
InternalMemScanMem16 (
IN CONST VOID *Buffer,
IN UINTN Length,
IN UINT16 Value
)
{
CONST UINT16 *Pointer;
Pointer = (CONST UINT16*)Buffer;
do {
if (*(Pointer++) == Value) {
return --Pointer;
}
} while (--Length != 0);
return NULL;
}
/**
Scans a target buffer for a 32-bit value, and returns a pointer to the
matching 32-bit value in the target buffer.
@param Buffer The pointer to the target buffer to scan.
@param Length The count of 32-bit value to scan. Must be non-zero.
@param Value The value to search for in the target buffer.
@return The pointer to the first occurrence or NULL if not found.
**/
CONST VOID *
EFIAPI
InternalMemScanMem32 (
IN CONST VOID *Buffer,
IN UINTN Length,
IN UINT32 Value
)
{
CONST UINT32 *Pointer;
Pointer = (CONST UINT32*)Buffer;
do {
if (*(Pointer++) == Value) {
return --Pointer;
}
} while (--Length != 0);
return NULL;
}
/**
Scans a target buffer for a 64-bit value, and returns a pointer to the
matching 64-bit value in the target buffer.
@param Buffer The pointer to the target buffer to scan.
@param Length The count of 64-bit value to scan. Must be non-zero.
@param Value The value to search for in the target buffer.
@return The pointer to the first occurrence or NULL if not found.
**/
CONST VOID *
EFIAPI
InternalMemScanMem64 (
IN CONST VOID *Buffer,
IN UINTN Length,
IN UINT64 Value
)
{
CONST UINT64 *Pointer;
Pointer = (CONST UINT64*)Buffer;
do {
if (*(Pointer++) == Value) {
return --Pointer;
}
} while (--Length != 0);
return NULL;
}
/**
Checks whether the contents of a buffer are all zeros.
@param Buffer The pointer to the buffer to be checked.
@param Length The size of the buffer (in bytes) to be checked.
@retval TRUE Contents of the buffer are all zeros.
@retval FALSE Contents of the buffer are not all zeros.
**/
BOOLEAN
EFIAPI
InternalMemIsZeroBuffer (
IN CONST VOID *Buffer,
IN UINTN Length
)
{
CONST UINT8 *BufferData;
UINTN Index;
BufferData = Buffer;
for (Index = 0; Index < Length; Index++) {
if (BufferData[Index] != 0) {
return FALSE;
}
}
return TRUE;
}