/mcs/class/I18N/Common/ByteEncoding.cs
C# | 495 lines | 295 code | 41 blank | 159 comment | 59 complexity | 4d0e333e3e408263c68517855ed62dfb MD5 | raw file
- /*
- * ByteEncoding.cs - Implementation of the "I18N.Common.ByteEncoding" class.
- *
- * Copyright (c) 2002 Southern Storm Software, Pty Ltd
- *
- * 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 I18N.Common
- {
- using System;
- using System.Runtime.InteropServices;
- using System.Text;
- // This class provides an abstract base for encodings that use a single
- // byte per character. The bulk of the work is done in this class, with
- // subclasses providing implementations of the "ToBytes" methods to perform
- // the char->byte conversion.
- [Serializable]
- public abstract class ByteEncoding : MonoEncoding
- {
- // Internal state.
- protected char[] toChars;
- protected String encodingName;
- protected String bodyName;
- protected String headerName;
- protected String webName;
- protected bool isBrowserDisplay;
- protected bool isBrowserSave;
- protected bool isMailNewsDisplay;
- protected bool isMailNewsSave;
- protected int windowsCodePage;
- static byte [] isNormalized;
- static byte [] isNormalizedComputed;
- static byte [] normalization_bytes;
- // Constructor.
- protected ByteEncoding(int codePage, char[] toChars,
- String encodingName, String bodyName,
- String headerName, String webName,
- bool isBrowserDisplay, bool isBrowserSave,
- bool isMailNewsDisplay, bool isMailNewsSave,
- int windowsCodePage)
- : base(codePage)
- {
- if (toChars.Length != byte.MaxValue + 1)
- throw new ArgumentException("toChars");
- this.toChars = toChars;
- this.encodingName = encodingName;
- this.bodyName = bodyName;
- this.headerName = headerName;
- this.webName = webName;
- this.isBrowserDisplay = isBrowserDisplay;
- this.isBrowserSave = isBrowserSave;
- this.isMailNewsDisplay = isMailNewsDisplay;
- this.isMailNewsSave = isMailNewsSave;
- this.windowsCodePage = windowsCodePage;
- }
- public override bool IsAlwaysNormalized (NormalizationForm form)
- {
- if (form != NormalizationForm.FormC)
- return false;
- if (isNormalized == null)
- isNormalized = new byte [0x10000 / 8];
- if (isNormalizedComputed == null)
- isNormalizedComputed = new byte [0x10000 / 8];
- if (normalization_bytes == null) {
- normalization_bytes = new byte [0x100];
- lock (normalization_bytes) {
- for (int i = 0; i < 0x100; i++)
- normalization_bytes [i] = (byte) i;
- }
- }
- byte offset = (byte) (1 << (CodePage % 8));
- if ((isNormalizedComputed [CodePage / 8] & offset) == 0) {
- Encoding e = Clone () as Encoding;
- e.DecoderFallback = new DecoderReplacementFallback ("");
- string s = e.GetString (normalization_bytes);
- // note that the flag only stores FormC information.
- if (s != s.Normalize (form))
- isNormalized [CodePage / 8] |= offset;
- isNormalizedComputed [CodePage / 8] |= offset;
- }
- return (isNormalized [CodePage / 8] & offset) == 0;
- }
- public override bool IsSingleByte {
- get { return true; }
- }
- public override int GetByteCount(String s)
- {
- if(s == null)
- {
- throw new ArgumentNullException("s");
- }
- return s.Length;
- }
- // Get the number of bytes needed to encode a character buffer.
- public unsafe override int GetByteCountImpl (char* chars, int count)
- {
- return count;
- }
- // Convert an array of characters into a byte buffer,
- // once the parameters have been validated.
- protected unsafe abstract void ToBytes (
- char* chars, int charCount, byte* bytes, int byteCount);
- /*
- protected unsafe virtual void ToBytes (
- char* chars, int charCount, byte* bytes, int byteCount)
- {
- // When it is not overriden, use ToBytes() with arrays.
- char [] carr = new char [charCount];
- Marshal.Copy ((IntPtr) chars, carr, 0, charCount);
- byte [] barr = new byte [byteCount];
- Marshal.Copy ((IntPtr) bytes, barr, 0, byteCount);
- ToBytes (carr, 0, charCount, barr, 0);
- }
- */
- // Convert an array of characters into a byte buffer,
- // once the parameters have been validated.
- protected unsafe virtual void ToBytes(char[] chars, int charIndex, int charCount,
- byte[] bytes, int byteIndex)
- {
- // When it is not overriden, use ToBytes() with pointers
- // (this is the ideal solution)
- if (charCount == 0 || bytes.Length == byteIndex)
- return;
- if (charIndex < 0 || charIndex > chars.Length) {
- throw new ArgumentOutOfRangeException
- ("charIndex", Strings.GetString("ArgRange_Array"));
- }
- if (byteIndex < 0 || byteIndex > bytes.Length) {
- throw new ArgumentOutOfRangeException
- ("byteIndex", Strings.GetString("ArgRange_Array"));
- }
- if (charCount < 0 || charIndex + charCount > chars.Length || byteIndex + charCount > bytes.Length) {
- throw new ArgumentOutOfRangeException
- ("charCount", Strings.GetString("ArgRange_Array"));
- }
- fixed (char* cptr = chars) {
- fixed (byte* bptr = bytes) {
- ToBytes (cptr + charIndex, charCount,
- bptr + byteIndex, bytes.Length - byteIndex);
- }
- }
- }
- /*
- // Convert a string into a byte buffer, once the parameters
- // have been validated.
- protected unsafe virtual void ToBytes(String s, int charIndex, int charCount,
- byte[] bytes, int byteIndex)
- {
- // When it is not overriden, use ToBytes() with pointers
- // (Ideal solution)
- if (s.Length == 0 || bytes.Length == byteIndex)
- return;
- fixed (char* cptr = s) {
- fixed (byte* bptr = bytes) {
- ToBytes (cptr + charIndex, charCount,
- bptr + byteIndex, bytes.Length - byteIndex);
- }
- }
- }
- */
- //[CLSCompliant (false)]
- public unsafe override int GetBytesImpl (char* chars, int charCount, byte* bytes, int byteCount)
- {
- ToBytes (chars, charCount, bytes, byteCount);
- return charCount;
- }
- /*
- // Get the bytes that result from encoding a character buffer.
- public 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", Strings.GetString("ArgRange_Array"));
- }
- if(charCount < 0 || charCount > (chars.Length - charIndex))
- {
- throw new ArgumentOutOfRangeException
- ("charCount", Strings.GetString("ArgRange_Array"));
- }
- if(byteIndex < 0 || byteIndex > bytes.Length)
- {
- throw new ArgumentOutOfRangeException
- ("byteIndex", Strings.GetString("ArgRange_Array"));
- }
- if((bytes.Length - byteIndex) < charCount)
- {
- throw new ArgumentException
- (Strings.GetString("Arg_InsufficientSpace"));
- }
- ToBytes(chars, charIndex, charCount, bytes, byteIndex);
- return charCount;
- }
- // Convenience wrappers for "GetBytes".
- public 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",
- Strings.GetString("ArgRange_StringIndex"));
- }
- if(charCount < 0 || charCount > (s.Length - charIndex))
- {
- throw new ArgumentOutOfRangeException
- ("charCount",
- Strings.GetString("ArgRange_StringRange"));
- }
- if(byteIndex < 0 || byteIndex > bytes.Length)
- {
- throw new ArgumentOutOfRangeException
- ("byteIndex", Strings.GetString("ArgRange_Array"));
- }
- if((bytes.Length - byteIndex) < charCount)
- {
- throw new ArgumentException
- (Strings.GetString("Arg_InsufficientSpace"));
- }
- ToBytes(s, charIndex, charCount, bytes, byteIndex);
- 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", Strings.GetString("ArgRange_Array"));
- }
- if(count < 0 || count > (bytes.Length - index))
- {
- throw new ArgumentOutOfRangeException
- ("count", Strings.GetString("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)
- {
- if(bytes == null)
- {
- throw new ArgumentNullException("bytes");
- }
- if(chars == null)
- {
- throw new ArgumentNullException("chars");
- }
- if(byteIndex < 0 || byteIndex > bytes.Length)
- {
- throw new ArgumentOutOfRangeException
- ("byteIndex", Strings.GetString("ArgRange_Array"));
- }
- if(byteCount < 0 || byteCount > (bytes.Length - byteIndex))
- {
- throw new ArgumentOutOfRangeException
- ("byteCount", Strings.GetString("ArgRange_Array"));
- }
- if(charIndex < 0 || charIndex > chars.Length)
- {
- throw new ArgumentOutOfRangeException
- ("charIndex", Strings.GetString("ArgRange_Array"));
- }
- if((chars.Length - charIndex) < byteCount)
- {
- throw new ArgumentException
- (Strings.GetString("Arg_InsufficientSpace"));
- }
- int count = byteCount;
- char[] cvt = toChars;
- while(count-- > 0)
- {
- chars[charIndex++] = cvt[(int)(bytes[byteIndex++])];
- }
- 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",
- Strings.GetString("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",
- Strings.GetString("ArgRange_NonNegative"));
- }
- return byteCount;
- }
- // Decode a buffer of bytes into a string.
- 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", Strings.GetString("ArgRange_Array"));
- }
- if(count < 0 || count > (bytes.Length - index))
- {
- throw new ArgumentOutOfRangeException
- ("count", Strings.GetString("ArgRange_Array"));
- }
- if (count == 0)
- return string.Empty;
- string s = new string ((char) 0, count);
- fixed (byte* bytePtr = bytes)
- fixed (char* charPtr = s)
- fixed (char* cvt = toChars) {
- byte* b = bytePtr + index;
- char* c = charPtr;
- while(count-- != 0)
- *(c++) = cvt[*(b++)];
- }
- return s;
- }
- public override String GetString(byte[] bytes)
- {
- if(bytes == null)
- {
- throw new ArgumentNullException("bytes");
- }
- return GetString (bytes, 0, bytes.Length);
- }
- #if !ECMA_COMPAT
- // Get the mail body name for this encoding.
- public override String BodyName
- {
- get
- {
- return bodyName;
- }
- }
- // Get the human-readable name for this encoding.
- public override String EncodingName
- {
- get
- {
- return encodingName;
- }
- }
- // Get the mail agent header name for this encoding.
- public override String HeaderName
- {
- get
- {
- return headerName;
- }
- }
- // Determine if this encoding can be displayed in a Web browser.
- public override bool IsBrowserDisplay
- {
- get
- {
- return isBrowserDisplay;
- }
- }
- // Determine if this encoding can be saved from a Web browser.
- public override bool IsBrowserSave
- {
- get
- {
- return isBrowserSave;
- }
- }
- // Determine if this encoding can be displayed in a mail/news agent.
- public override bool IsMailNewsDisplay
- {
- get
- {
- return isMailNewsDisplay;
- }
- }
- // Determine if this encoding can be saved from a mail/news agent.
- public override bool IsMailNewsSave
- {
- get
- {
- return isMailNewsSave;
- }
- }
- // Get the IANA-preferred Web name for this encoding.
- public override String WebName
- {
- get
- {
- return webName;
- }
- }
- // Get the Windows code page represented by this object.
- public override int WindowsCodePage
- {
- get
- {
- return windowsCodePage;
- }
- }
- #endif // !ECMA_COMPAT
- }; // class ByteEncoding
- }; // namespace I18N.Encoding