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// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
/*============================================================
**
** Class: BitConverter
**
**
** Purpose: Allows developers to view the base data types as
** an arbitrary array of bits.
**
**
===========================================================*/
namespace System {
using System;
using System.Runtime.CompilerServices;
using System.Diagnostics.Contracts;
using System.Security;
// The BitConverter class contains methods for
// converting an array of bytes to one of the base data
// types, as well as for converting a base data type to an
// array of bytes.
//
// Only statics, does not need to be marked with the serializable attribute
public static class BitConverter {
// This field indicates the "endianess" of the architecture.
// The value is set to true if the architecture is
// little endian; false if it is big endian.
#if BIGENDIAN
public static readonly bool IsLittleEndian /* = false */;
#else
public static readonly bool IsLittleEndian = true;
#endif
// Converts a byte into an array of bytes with length one.
public static byte[] GetBytes(bool value) {
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 1);
byte[] r = new byte[1];
r[0] = (value ? (byte)Boolean.True : (byte)Boolean.False );
return r;
}
// Converts a char into an array of bytes with length two.
public static byte[] GetBytes(char value)
{
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 2);
return GetBytes((short)value);
}
// Converts a short into an array of bytes with length
// two.
[System.Security.SecuritySafeCritical] // auto-generated
public unsafe static byte[] GetBytes(short value)
{
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 2);
byte[] bytes = new byte[2];
fixed(byte* b = bytes)
*((short*)b) = value;
return bytes;
}
// Converts an int into an array of bytes with length
// four.
[System.Security.SecuritySafeCritical] // auto-generated
public unsafe static byte[] GetBytes(int value)
{
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 4);
byte[] bytes = new byte[4];
fixed(byte* b = bytes)
*((int*)b) = value;
return bytes;
}
// Converts a long into an array of bytes with length
// eight.
[System.Security.SecuritySafeCritical] // auto-generated
public unsafe static byte[] GetBytes(long value)
{
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 8);
byte[] bytes = new byte[8];
fixed(byte* b = bytes)
*((long*)b) = value;
return bytes;
}
// Converts an ushort into an array of bytes with
// length two.
[CLSCompliant(false)]
public static byte[] GetBytes(ushort value) {
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 2);
return GetBytes((short)value);
}
// Converts an uint into an array of bytes with
// length four.
[CLSCompliant(false)]
public static byte[] GetBytes(uint value) {
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 4);
return GetBytes((int)value);
}
// Converts an unsigned long into an array of bytes with
// length eight.
[CLSCompliant(false)]
public static byte[] GetBytes(ulong value) {
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 8);
return GetBytes((long)value);
}
// Converts a float into an array of bytes with length
// four.
[System.Security.SecuritySafeCritical] // auto-generated
public unsafe static byte[] GetBytes(float value)
{
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 4);
return GetBytes(*(int*)&value);
}
// Converts a double into an array of bytes with length
// eight.
[System.Security.SecuritySafeCritical] // auto-generated
public unsafe static byte[] GetBytes(double value)
{
Contract.Ensures(Contract.Result<byte[]>() != null);
Contract.Ensures(Contract.Result<byte[]>().Length == 8);
return GetBytes(*(long*)&value);
}
// Converts an array of bytes into a char.
public static char ToChar(byte[] value, int startIndex)
{
if (value == null) {
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
}
if ((uint)startIndex >= value.Length) {
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
}
if (startIndex > value.Length - 2) {
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
}
Contract.EndContractBlock();
return (char)ToInt16(value, startIndex);
}
// Converts an array of bytes into a short.
[System.Security.SecuritySafeCritical] // auto-generated
public static unsafe short ToInt16(byte[] value, int startIndex) {
if( value == null) {
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
}
if ((uint) startIndex >= value.Length) {
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
}
if (startIndex > value.Length -2) {
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
}
Contract.EndContractBlock();
fixed( byte * pbyte = &value[startIndex]) {
if( startIndex % 2 == 0) { // data is aligned
return *((short *) pbyte);
}
else {
if( IsLittleEndian) {
return (short)((*pbyte) | (*(pbyte + 1) << 8)) ;
}
else {
return (short)((*pbyte << 8) | (*(pbyte + 1)));
}
}
}
}
// Converts an array of bytes into an int.
[System.Security.SecuritySafeCritical] // auto-generated
public static unsafe int ToInt32 (byte[] value, int startIndex) {
if( value == null) {
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
}
if ((uint) startIndex >= value.Length) {
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
}
if (startIndex > value.Length -4) {
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
}
Contract.EndContractBlock();
fixed( byte * pbyte = &value[startIndex]) {
if( startIndex % 4 == 0) { // data is aligned
return *((int *) pbyte);
}
else {
if( IsLittleEndian) {
return (*pbyte) | (*(pbyte + 1) << 8) | (*(pbyte + 2) << 16) | (*(pbyte + 3) << 24);
}
else {
return (*pbyte << 24) | (*(pbyte + 1) << 16) | (*(pbyte + 2) << 8) | (*(pbyte + 3));
}
}
}
}
// Converts an array of bytes into a long.
[System.Security.SecuritySafeCritical] // auto-generated
public static unsafe long ToInt64 (byte[] value, int startIndex) {
if (value == null) {
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
}
if ((uint) startIndex >= value.Length) {
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
}
if (startIndex > value.Length -8) {
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
}
Contract.EndContractBlock();
fixed( byte * pbyte = &value[startIndex]) {
if( startIndex % 8 == 0) { // data is aligned
return *((long *) pbyte);
}
else {
if( IsLittleEndian) {
int i1 = (*pbyte) | (*(pbyte + 1) << 8) | (*(pbyte + 2) << 16) | (*(pbyte + 3) << 24);
int i2 = (*(pbyte+4)) | (*(pbyte + 5) << 8) | (*(pbyte + 6) << 16) | (*(pbyte + 7) << 24);
return (uint)i1 | ((long)i2 << 32);
}
else {
int i1 = (*pbyte << 24) | (*(pbyte + 1) << 16) | (*(pbyte + 2) << 8) | (*(pbyte + 3));
int i2 = (*(pbyte+4) << 24) | (*(pbyte + 5) << 16) | (*(pbyte + 6) << 8) | (*(pbyte + 7));
return (uint)i2 | ((long)i1 << 32);
}
}
}
}
// Converts an array of bytes into an ushort.
//
[CLSCompliant(false)]
public static ushort ToUInt16(byte[] value, int startIndex)
{
if (value == null)
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
if ((uint)startIndex >= value.Length)
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
if (startIndex > value.Length - 2)
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
Contract.EndContractBlock();
return (ushort)ToInt16(value, startIndex);
}
// Converts an array of bytes into an uint.
//
[CLSCompliant(false)]
public static uint ToUInt32(byte[] value, int startIndex)
{
if (value == null)
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
if ((uint)startIndex >= value.Length)
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
if (startIndex > value.Length - 4)
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
Contract.EndContractBlock();
return (uint)ToInt32(value, startIndex);
}
// Converts an array of bytes into an unsigned long.
//
[CLSCompliant(false)]
public static ulong ToUInt64(byte[] value, int startIndex)
{
if (value == null)
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
if ((uint)startIndex >= value.Length)
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
if (startIndex > value.Length - 8)
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
Contract.EndContractBlock();
return (ulong)ToInt64(value, startIndex);
}
// Converts an array of bytes into a float.
[System.Security.SecuritySafeCritical] // auto-generated
unsafe public static float ToSingle (byte[] value, int startIndex)
{
if (value == null)
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
if ((uint)startIndex >= value.Length)
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
if (startIndex > value.Length - 4)
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
Contract.EndContractBlock();
int val = ToInt32(value, startIndex);
return *(float*)&val;
}
// Converts an array of bytes into a double.
[System.Security.SecuritySafeCritical] // auto-generated
unsafe public static double ToDouble (byte[] value, int startIndex)
{
if (value == null)
ThrowHelper.ThrowArgumentNullException(ExceptionArgument.value);
if ((uint)startIndex >= value.Length)
ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument.startIndex, ExceptionResource.ArgumentOutOfRange_Index);
if (startIndex > value.Length - 8)
ThrowHelper.ThrowArgumentException(ExceptionResource.Arg_ArrayPlusOffTooSmall);
Contract.EndContractBlock();
long val = ToInt64(value, startIndex);
return *(double*)&val;
}
private static char GetHexValue(int i) {
Contract.Assert( i >=0 && i <16, "i is out of range.");
if (i<10) {
return (char)(i + '0');
}
return (char)(i - 10 + 'A');
}
// Converts an array of bytes into a String.
public static String ToString (byte[] value, int startIndex, int length) {
if (value == null) {
throw new ArgumentNullException("value");
}
if (startIndex < 0 || startIndex >= value.Length && startIndex > 0) { // Don't throw for a 0 length array.
throw new ArgumentOutOfRangeException("startIndex", Environment.GetResourceString("ArgumentOutOfRange_StartIndex"));
}
if (length < 0) {
throw new ArgumentOutOfRangeException("length", Environment.GetResourceString("ArgumentOutOfRange_GenericPositive"));
}
if (startIndex > value.Length - length) {
throw new ArgumentException(Environment.GetResourceString("Arg_ArrayPlusOffTooSmall"));
}
Contract.EndContractBlock();
if (length == 0) {
return string.Empty;
}
if (length > (Int32.MaxValue / 3)) {
// (Int32.MaxValue / 3) == 715,827,882 Bytes == 699 MB
throw new ArgumentOutOfRangeException("length", Environment.GetResourceString("ArgumentOutOfRange_LengthTooLarge", (Int32.MaxValue / 3)));
}
int chArrayLength = length * 3;
char[] chArray = new char[chArrayLength];
int i = 0;
int index = startIndex;
for (i = 0; i < chArrayLength; i += 3) {
byte b = value[index++];
chArray[i]= GetHexValue(b/16);
chArray[i+1] = GetHexValue(b%16);
chArray[i+2] = '-';
}
// We don't need the last '-' character
return new String(chArray, 0, chArray.Length - 1);
}
// Converts an array of bytes into a String.
public static String ToString(byte [] value) {
if (value == null)
throw new ArgumentNullException("value");
Contract.Ensures(Contract.Result<String>() != null);
Contract.EndContractBlock();
return ToString(value, 0, value.Length);
}
// Converts an array of bytes into a String.
public static String ToString (byte [] value, int startIndex) {
if (value == null)
throw new ArgumentNullException("value");
Contract.Ensures(Contract.Result<String>() != null);
Contract.EndContractBlock();
return ToString(value, startIndex, value.Length - startIndex);
}
/*==================================ToBoolean===================================
**Action: Convert an array of bytes to a boolean value. We treat this array
** as if the first 4 bytes were an Int4 an operate on this value.
**Returns: True if the Int4 value of the first 4 bytes is non-zero.
**Arguments: value -- The byte array
** startIndex -- The position within the array.
**Exceptions: See ToInt4.
==============================================================================*/
// Converts an array of bytes into a boolean.
public static bool ToBoolean(byte[] value, int startIndex) {
if (value==null)
throw new ArgumentNullException("value");
if (startIndex < 0)
throw new ArgumentOutOfRangeException("startIndex", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (startIndex > value.Length - 1)
throw new ArgumentOutOfRangeException("startIndex", Environment.GetResourceString("ArgumentOutOfRange_Index"));
Contract.EndContractBlock();
return (value[startIndex]==0)?false:true;
}
[SecuritySafeCritical]
public static unsafe long DoubleToInt64Bits(double value) {
// If we're on a big endian machine, what should this method do? You could argue for
// either big endian or little endian, depending on whether you are writing to a file that
// should be used by other programs on that processor, or for compatibility across multiple
// formats. Because this is ambiguous, we're excluding this from the Portable Library & Win8 Profile.
// If we ever run on big endian machines, produce two versions where endianness is specified.
Contract.Assert(IsLittleEndian, "This method is implemented assuming little endian with an ambiguous spec.");
return *((long *)&value);
}
[SecuritySafeCritical]
public static unsafe double Int64BitsToDouble(long value) {
// If we're on a big endian machine, what should this method do? You could argue for
// either big endian or little endian, depending on whether you are writing to a file that
// should be used by other programs on that processor, or for compatibility across multiple
// formats. Because this is ambiguous, we're excluding this from the Portable Library & Win8 Profile.
// If we ever run on big endian machines, produce two versions where endianness is specified.
Contract.Assert(IsLittleEndian, "This method is implemented assuming little endian with an ambiguous spec.");
return *((double*)&value);
}
}
}
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