/*
* ASCIIEncoding.cs - Implementation of the "System.Text.ASCIIEncoding" class.
*
* Copyright (c) 2001 Southern Storm Software, Pty Ltd
* Copyright (C) 2003 Novell, Inc.
* Copyright (C) 2004 Novell, Inc (http://www.novell.com)
*
* 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 ASCIIEncoding : Encoding
{
// Magic number used by Windows for "ASCII".
internal const int ASCII_CODE_PAGE = 20127;
// Constructor.
public ASCIIEncoding () : base(ASCII_CODE_PAGE) {
body_name = header_name = web_name= "us-ascii";
encoding_name = "US-ASCII";
is_mail_news_display = true;
is_mail_news_save = true;
}
[ComVisible (false)]
public override bool IsSingleByte {
get { return true; }
}
// 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;
}
// Convenience wrappers for "GetByteCount".
public override int GetByteCount (String chars)
{
if (chars == null) {
throw new ArgumentNullException ("chars");
}
return chars.Length;
}
// Get the bytes that result from encoding a character buffer.
public override int GetBytes (char[] chars, int charIndex, int charCount,
byte[] bytes, int byteIndex)
{
EncoderFallbackBuffer buffer = null;
char [] fallback_chars = null;
return GetBytes (chars, charIndex, charCount, bytes, byteIndex,
ref buffer, ref fallback_chars);
}
int GetBytes (char[] chars, int charIndex, int charCount,
byte[] bytes, int byteIndex,
ref EncoderFallbackBuffer buffer,
ref char [] fallback_chars)
{
if (chars == null)
throw new ArgumentNullException ("chars");
unsafe {
fixed (char *cptr = chars) {
return InternalGetBytes (cptr, chars.Length, charIndex, charCount, bytes, byteIndex, ref buffer, ref fallback_chars);
}
}
}
// Convenience wrappers for "GetBytes".
public override int GetBytes (String chars, int charIndex, int charCount, byte[] bytes, int byteIndex)
{
EncoderFallbackBuffer buffer = null;
char [] fallback_chars = null;
return GetBytes (chars, charIndex, charCount, bytes, byteIndex,
ref buffer, ref fallback_chars);
}
int GetBytes (String chars, int charIndex, int charCount,
byte[] bytes, int byteIndex,
ref EncoderFallbackBuffer buffer,
ref char [] fallback_chars)
{
if (chars == null)
throw new ArgumentNullException ("chars");
unsafe {
fixed (char *cptr = chars) {
return InternalGetBytes (cptr, chars.Length, charIndex, charCount, bytes, byteIndex, ref buffer, ref fallback_chars);
}
}
}
unsafe int InternalGetBytes (char *chars, int charLength, int charIndex, int charCount,
byte[] bytes, int byteIndex,
ref EncoderFallbackBuffer buffer,
ref char [] fallback_chars)
{
if (bytes == null)
throw new ArgumentNullException ("bytes");
if (charIndex < 0 || charIndex > charLength)
throw new ArgumentOutOfRangeException ("charIndex", _("ArgRange_StringIndex"));
if (charCount < 0 || charCount > (charLength - charIndex))
throw new ArgumentOutOfRangeException ("charCount", _("ArgRange_StringRange"));
if (byteIndex < 0 || byteIndex > bytes.Length)
throw new ArgumentOutOfRangeException ("byteIndex", _("ArgRange_Array"));
if ((bytes.Length - byteIndex) < charCount)
throw new ArgumentException (_("Arg_InsufficientSpace"));
int count = charCount;
char ch;
while (count-- > 0) {
ch = chars [charIndex++];
if (ch < (char)0x80) {
bytes [byteIndex++] = (byte)ch;
} else {
if (buffer == null)
buffer = EncoderFallback.CreateFallbackBuffer ();
if (Char.IsSurrogate (ch) && count > 1 &&
Char.IsSurrogate (chars [charIndex]))
buffer.Fallback (ch, chars [charIndex], charIndex++ - 1);
else
buffer.Fallback (ch, charIndex - 1);
if (fallback_chars == null || fallback_chars.Length < buffer.Remaining)
fallback_chars = new char [buffer.Remaining];
for (int i = 0; i < fallback_chars.Length; i++)
fallback_chars [i] = buffer.GetNextChar ();
byteIndex += GetBytes (fallback_chars, 0,
fallback_chars.Length, bytes, byteIndex,
ref buffer, ref fallback_chars);
}
}
return charCount;
}
// 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;
}
// Get the characters that result from decoding a byte buffer.
public override int GetChars (byte[] bytes, int byteIndex, int byteCount, char[] chars, int charIndex)
{
DecoderFallbackBuffer buffer = null;
return GetChars (bytes, byteIndex, byteCount, chars,
charIndex, ref buffer);
}
int GetChars (byte[] bytes, int byteIndex, int byteCount,
char[] chars, int charIndex,
ref DecoderFallbackBuffer buffer)
{
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 ((chars.Length - charIndex) < byteCount)
throw new ArgumentException (_("Arg_InsufficientSpace"));
int count = byteCount;
while (count-- > 0) {
char c = (char) bytes [byteIndex++];
if (c < '\x80')
chars [charIndex++] = c;
else {
if (buffer == null)
buffer = DecoderFallback.CreateFallbackBuffer ();
buffer.Fallback (bytes, byteIndex);
while (buffer.Remaining > 0)
chars [charIndex++] = buffer.GetNextChar ();
}
}
return byteCount;
}
// 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;
}
// 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;
}
// Decode a buffer of bytes into a string.
public override String GetString (byte[] bytes, int byteIndex, int byteCount)
{
if (bytes == null) {
throw new ArgumentNullException ("bytes");
}
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 (byteCount == 0)
return String.Empty;
unsafe {
fixed (byte* bytePtr = bytes) {
string s = string.InternalAllocateStr (byteCount);
fixed (char* charPtr = s) {
byte* currByte = bytePtr + byteIndex;
byte* lastByte = currByte + byteCount;
char* currChar = charPtr;
while (currByte < lastByte) {
byte b = currByte++ [0];
currChar++ [0] = b <= 0x7F ? (char) b : (char) '?';
}
}
return s;
}
}
}
[CLSCompliantAttribute (false)]
[ComVisible (false)]
public unsafe override int GetBytes (char *chars, int charCount, byte *bytes, int byteCount)
{
if (chars == null)
throw new ArgumentNullException ("chars");
if (bytes == null)
throw new ArgumentNullException ("bytes");
if (charCount < 0)
throw new ArgumentOutOfRangeException ("charCount");
if (byteCount < 0)
throw new ArgumentOutOfRangeException ("byteCount");
if (byteCount < charCount)
throw new ArgumentException ("bytecount is less than the number of bytes required", "byteCount");
for (int i = 0; i < charCount; i++){
char c = chars [i];
bytes [i] = (byte) ((c < (char) 0x80) ? c : '?');
}
return 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");
if (charCount < byteCount)
throw new ArgumentException ("charcount is less than the number of bytes required", "charCount");
for (int i = 0; i < byteCount; i++){
byte b = bytes [i];
chars [i] = b > 127 ? '?' : (char) b;
}
return byteCount;
}
[CLSCompliantAttribute(false)]
[ComVisible (false)]
public unsafe override int GetCharCount (byte *bytes, int count)
{
return count;
}
[CLSCompliantAttribute(false)]
[ComVisible (false)]
public unsafe override int GetByteCount (char *chars, int count)
{
return count;
}
[ComVisible (false)]
public override Decoder GetDecoder ()
{
return base.GetDecoder ();
}
[ComVisible (false)]
public override Encoder GetEncoder ()
{
return base.GetEncoder ();
}
}; // class ASCIIEncoding
}; // namespace System.Text
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