blob: 8bc9321e666538481cf53d5048bf1a3d4bfc81fd [file] [log] [blame]
/** @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>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#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 The 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;
}