/*
* UnicodeEncoding.cs - Implementation of the
* "System.Text.UnicodeEncoding" class.
*
* Copyright (c) 2001, 2002 Southern Storm Software, Pty Ltd
* Copyright (C) 2003, 2004 Novell, Inc.
* Copyright (C) 2006 Kornl Pl <http://www.kornelpal.hu/>
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
namespace System.Text{
using System;
using System.Runtime.InteropServices;
[Serializable]
[ComVisible (true)]
[MonoLimitation ("Serialization format not compatible with .NET")]
public class UnicodeEncoding : Encoding
{
// Magic numbers used by Windows for Unicode.
internal const int UNICODE_CODE_PAGE = 1200;
internal const int BIG_UNICODE_CODE_PAGE = 1201;
#if !ECMA_COMPAT
// Size of characters in this encoding.
public const int CharSize = 2;
#endif
// Internal state.
private bool bigEndian;
private bool byteOrderMark;
// Constructors.
public UnicodeEncoding () : this (false, true)
{
bigEndian = false;
byteOrderMark = true;
}
public UnicodeEncoding (bool bigEndian, bool byteOrderMark)
: this (bigEndian, byteOrderMark, false)
{
}
public UnicodeEncoding (bool bigEndian, bool byteOrderMark, bool throwOnInvalidBytes)
: base ((bigEndian ? BIG_UNICODE_CODE_PAGE : UNICODE_CODE_PAGE))
{
if (throwOnInvalidBytes)
SetFallbackInternal (null, new DecoderExceptionFallback ());
else
SetFallbackInternal (null, new DecoderReplacementFallback ("\uFFFD"));
this.bigEndian = bigEndian;
this.byteOrderMark = byteOrderMark;
if (bigEndian){
body_name = "unicodeFFFE";
encoding_name = "Unicode (Big-Endian)";
header_name = "unicodeFFFE";
is_browser_save = false;
web_name = "unicodeFFFE";
} else {
body_name = "utf-16";
encoding_name = "Unicode";
header_name = "utf-16";
is_browser_save = true;
web_name = "utf-16";
}
// Windows reports the same code page number for
// both the little-endian and big-endian forms.
windows_code_page = UNICODE_CODE_PAGE;
}
// Get the number of bytes needed to encode a character buffer.
public override int GetByteCount (char[] chars, int index, int count)
{
if (chars == null) {
throw new ArgumentNullException ("chars");
}
if (index < 0 || index > chars.Length) {
throw new ArgumentOutOfRangeException ("index", _("ArgRange_Array"));
}
if (count < 0 || count > (chars.Length - index)) {
throw new ArgumentOutOfRangeException ("count", _("ArgRange_Array"));
}
return count * 2;
}
public override int GetByteCount (String s)
{
if (s == null) {
throw new ArgumentNullException ("s");
}
return s.Length * 2;
}
[CLSCompliantAttribute (false)]
[ComVisible (false)]
public unsafe override int GetByteCount (char* chars, int count)
{
if (chars == null)
throw new ArgumentNullException ("chars");
if (count < 0)
throw new ArgumentOutOfRangeException ("count");
return count * 2;
}
// Get the bytes that result from encoding a character buffer.
public unsafe override int GetBytes (char [] chars, int charIndex, int charCount,
byte [] bytes, int byteIndex)
{
if (chars == null) {
throw new ArgumentNullException ("chars");
}
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
if (charIndex < 0 || charIndex > chars.Length) {
throw new ArgumentOutOfRangeException ("charIndex", _("ArgRange_Array"));
}
if (charCount < 0 || charCount > (chars.Length - charIndex)) {
throw new ArgumentOutOfRangeException ("charCount", _("ArgRange_Array"));
}
if (byteIndex < 0 || byteIndex > bytes.Length) {
throw new ArgumentOutOfRangeException ("byteIndex", _("ArgRange_Array"));
}
if (charCount == 0)
return 0;
int byteCount = bytes.Length - byteIndex;
if (bytes.Length == 0)
bytes = new byte [1];
fixed (char* charPtr = chars)
fixed (byte* bytePtr = bytes)
return GetBytesInternal (charPtr + charIndex, charCount, bytePtr + byteIndex, byteCount);
}
public unsafe override int GetBytes (String s, int charIndex, int charCount,
byte [] bytes, int byteIndex)
{
if (s == null) {
throw new ArgumentNullException ("s");
}
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
if (charIndex < 0 || charIndex > s.Length) {
throw new ArgumentOutOfRangeException ("charIndex", _("ArgRange_StringIndex"));
}
if (charCount < 0 || charCount > (s.Length - charIndex)) {
throw new ArgumentOutOfRangeException ("charCount", _("ArgRange_StringRange"));
}
if (byteIndex < 0 || byteIndex > bytes.Length) {
throw new ArgumentOutOfRangeException ("byteIndex", _("ArgRange_Array"));
}
// For consistency
if (charCount == 0)
return 0;
int byteCount = bytes.Length - byteIndex;
if (bytes.Length == 0)
bytes = new byte [1];
fixed (char* charPtr = s)
fixed (byte* bytePtr = bytes)
return GetBytesInternal (charPtr + charIndex, charCount, bytePtr + byteIndex, byteCount);
}
[CLSCompliantAttribute (false)]
[ComVisible (false)]
public unsafe override int GetBytes (char* chars, int charCount,
byte* bytes, int byteCount)
{
if (bytes == null)
throw new ArgumentNullException ("bytes");
if (chars == null)
throw new ArgumentNullException ("chars");
if (charCount < 0)
throw new ArgumentOutOfRangeException ("charCount");
if (byteCount < 0)
throw new ArgumentOutOfRangeException ("byteCount");
return GetBytesInternal (chars, charCount, bytes, byteCount);
}
private unsafe int GetBytesInternal (char* chars, int charCount,
byte* bytes, int byteCount)
{
int count = charCount * 2;
if (byteCount < count)
throw new ArgumentException (_("Arg_InsufficientSpace"));
CopyChars ((byte*) chars, bytes, count, bigEndian);
return count;
}
// Get the number of characters needed to decode a byte buffer.
public override int GetCharCount (byte[] bytes, int index, int count)
{
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
if (index < 0 || index > bytes.Length) {
throw new ArgumentOutOfRangeException ("index", _("ArgRange_Array"));
}
if (count < 0 || count > (bytes.Length - index)) {
throw new ArgumentOutOfRangeException ("count", _("ArgRange_Array"));
}
return count / 2;
}
[CLSCompliantAttribute (false)]
[ComVisible (false)]
public unsafe override int GetCharCount (byte* bytes, int count)
{
if (bytes == null)
throw new ArgumentNullException ("bytes");
if (count < 0)
throw new ArgumentOutOfRangeException ("count");
return count / 2;
}
// Get the characters that result from decoding a byte buffer.
public unsafe override int GetChars (byte [] bytes, int byteIndex, int byteCount,
char [] chars, int charIndex)
{
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
if (chars == null) {
throw new ArgumentNullException ("chars");
}
if (byteIndex < 0 || byteIndex > bytes.Length) {
throw new ArgumentOutOfRangeException ("byteIndex", _("ArgRange_Array"));
}
if (byteCount < 0 || byteCount > (bytes.Length - byteIndex)) {
throw new ArgumentOutOfRangeException ("byteCount", _("ArgRange_Array"));
}
if (charIndex < 0 || charIndex > chars.Length) {
throw new ArgumentOutOfRangeException ("charIndex", _("ArgRange_Array"));
}
if (byteCount == 0)
return 0;
int charCount = chars.Length - charIndex;
if (chars.Length == 0)
chars = new char [1];
fixed (byte* bytePtr = bytes)
fixed (char* charPtr = chars)
return GetCharsInternal (bytePtr + byteIndex, byteCount, charPtr + charIndex, charCount);
}
[CLSCompliantAttribute (false)]
[ComVisible (false)]
public unsafe override int GetChars (byte* bytes, int byteCount,
char* chars, int charCount)
{
if (bytes == null)
throw new ArgumentNullException ("bytes");
if (chars == null)
throw new ArgumentNullException ("chars");
if (charCount < 0)
throw new ArgumentOutOfRangeException ("charCount");
if (byteCount < 0)
throw new ArgumentOutOfRangeException ("byteCount");
return GetCharsInternal (bytes, byteCount, chars, charCount);
}
// Decode a buffer of bytes into a string.
[ComVisible (false)]
public unsafe override String GetString (byte [] bytes, int index, int count)
{
if (bytes == null)
throw new ArgumentNullException ("bytes");
if (index < 0 || index > bytes.Length)
throw new ArgumentOutOfRangeException ("index", _("ArgRange_Array"));
if (count < 0 || count > (bytes.Length - index))
throw new ArgumentOutOfRangeException ("count", _("ArgRange_Array"));
if (count == 0)
return string.Empty;
// GetCharCountInternal
int charCount = count / 2;
string s = string.InternalAllocateStr (charCount);
fixed (byte* bytePtr = bytes)
fixed (char* charPtr = s)
GetCharsInternal (bytePtr + index, count, charPtr, charCount);
return s;
}
private unsafe int GetCharsInternal (byte* bytes, int byteCount,
char* chars, int charCount)
{
int count = byteCount / 2;
// Validate that we have sufficient space in "chars".
if (charCount < count)
throw new ArgumentException (_("Arg_InsufficientSpace"));
CopyChars (bytes, (byte*) chars, byteCount, bigEndian);
return count;
}
[ComVisible (false)]
public override Encoder GetEncoder ()
{
return(base.GetEncoder ());
}
// Get the maximum number of bytes needed to encode a
// specified number of characters.
public override int GetMaxByteCount (int charCount)
{
if (charCount < 0) {
throw new ArgumentOutOfRangeException ("charCount", _("ArgRange_NonNegative"));
}
return charCount * 2;
}
// Get the maximum number of characters needed to decode a
// specified number of bytes.
public override int GetMaxCharCount (int byteCount)
{
if (byteCount < 0) {
throw new ArgumentOutOfRangeException
("byteCount", _("ArgRange_NonNegative"));
}
return byteCount / 2;
}
// Get a Unicode-specific decoder that is attached to this instance.
public override Decoder GetDecoder ()
{
return new UnicodeDecoder (bigEndian);
}
// Get the Unicode preamble.
public override byte[] GetPreamble ()
{
if (byteOrderMark) {
byte[] preamble = new byte[2];
if (bigEndian) {
preamble[0] = (byte)0xFE;
preamble[1] = (byte)0xFF;
} else {
preamble[0] = (byte)0xFF;
preamble[1] = (byte)0xFE;
}
return preamble;
} else {
return new byte [0];
}
}
// Determine if this object is equal to another.
public override bool Equals (Object value)
{
UnicodeEncoding enc = (value as UnicodeEncoding);
if (enc != null) {
return (codePage == enc.codePage &&
bigEndian == enc.bigEndian &&
byteOrderMark == enc.byteOrderMark);
} else {
return false;
}
}
// Get the hash code for this object.
public override int GetHashCode ()
{
return base.GetHashCode ();
}
private unsafe static void CopyChars (byte* src, byte* dest, int count, bool bigEndian)
{
if (BitConverter.IsLittleEndian != bigEndian) {
string.memcpy (dest, src, count & unchecked ((int) 0xFFFFFFFE));
return;
}
switch (count) {
case 0:
return;
case 1:
return;
case 2:
goto Count2;
case 3:
goto Count2;
case 4:
goto Count4;
case 5:
goto Count4;
case 6:
goto Count4;
case 7:
goto Count4;
case 8:
goto Count8;
case 9:
goto Count8;
case 10:
goto Count8;
case 11:
goto Count8;
case 12:
goto Count8;
case 13:
goto Count8;
case 14:
goto Count8;
case 15:
goto Count8;
}
do {
dest [0] = src [1];
dest [1] = src [0];
dest [2] = src [3];
dest [3] = src [2];
dest [4] = src [5];
dest [5] = src [4];
dest [6] = src [7];
dest [7] = src [6];
dest [8] = src [9];
dest [9] = src [8];
dest [10] = src [11];
dest [11] = src [10];
dest [12] = src [13];
dest [13] = src [12];
dest [14] = src [15];
dest [15] = src [14];
dest += 16;
src += 16;
count -= 16;
} while ((count & unchecked ((int) 0xFFFFFFF0)) != 0);
switch (count) {
case 0:
return;
case 1:
return;
case 2:
goto Count2;
case 3:
goto Count2;
case 4:
goto Count4;
case 5:
goto Count4;
case 6:
goto Count4;
case 7:
goto Count4;
}
Count8:;
dest [0] = src [1];
dest [1] = src [0];
dest [2] = src [3];
dest [3] = src [2];
dest [4] = src [5];
dest [5] = src [4];
dest [6] = src [7];
dest [7] = src [6];
dest += 8;
src += 8;
if ((count & 4) == 0)
goto TestCount2;
Count4:;
dest [0] = src [1];
dest [1] = src [0];
dest [2] = src [3];
dest [3] = src [2];
dest += 4;
src += 4;
TestCount2:;
if ((count & 2) == 0)
return;
Count2:;
dest [0] = src [1];
dest [1] = src [0];
}
// Unicode decoder implementation.
private sealed class UnicodeDecoder : Decoder
{
private bool bigEndian;
private int leftOverByte;
// Constructor.
public UnicodeDecoder (bool bigEndian)
{
this.bigEndian = bigEndian;
leftOverByte = -1;
}
// Override inherited methods.
public override int GetCharCount (byte[] bytes, int index, int count)
{
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
if (index < 0 || index > bytes.Length) {
throw new ArgumentOutOfRangeException ("index", _("ArgRange_Array"));
}
if (count < 0 || count > (bytes.Length - index)) {
throw new ArgumentOutOfRangeException ("count", _("ArgRange_Array"));
}
if (leftOverByte != -1) {
return (count + 1) / 2;
} else {
return count / 2;
}
}
public unsafe override int GetChars (byte [] bytes, int byteIndex,
int byteCount, char [] chars,
int charIndex)
{
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
if (chars == null) {
throw new ArgumentNullException ("chars");
}
if (byteIndex < 0 || byteIndex > bytes.Length) {
throw new ArgumentOutOfRangeException ("byteIndex", _("ArgRange_Array"));
}
if (byteCount < 0 || byteCount > (bytes.Length - byteIndex)) {
throw new ArgumentOutOfRangeException ("byteCount", _("ArgRange_Array"));
}
if (charIndex < 0 || charIndex > chars.Length) {
throw new ArgumentOutOfRangeException ("charIndex", _("ArgRange_Array"));
}
if (byteCount == 0)
return 0;
int leftOver = leftOverByte;
int count;
if (leftOver != -1)
count = (byteCount + 1) / 2;
else
count = byteCount / 2;
if (chars.Length - charIndex < count)
throw new ArgumentException (_("Arg_InsufficientSpace"));
if (leftOver != -1) {
if (bigEndian)
chars [charIndex] = unchecked ((char) ((leftOver << 8) | (int) bytes [byteIndex]));
else
chars [charIndex] = unchecked ((char) (((int) bytes [byteIndex] << 8) | leftOver));
charIndex++;
byteIndex++;
byteCount--;
}
if ((byteCount & unchecked ((int) 0xFFFFFFFE)) != 0)
fixed (byte* bytePtr = bytes)
fixed (char* charPtr = chars)
CopyChars (bytePtr + byteIndex, (byte*) (charPtr + charIndex), byteCount, bigEndian);
if ((byteCount & 1) == 0)
leftOverByte = -1;
else
leftOverByte = bytes [byteCount + byteIndex - 1];
return count;
}
} // class UnicodeDecoder
}; // class UnicodeEncoding
}; // namespace System.Text
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