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-rw-r--r--src/mscorlib/src/System/Text/UTF32Encoding.cs1003
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diff --git a/src/mscorlib/src/System/Text/UTF32Encoding.cs b/src/mscorlib/src/System/Text/UTF32Encoding.cs
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--- a/src/mscorlib/src/System/Text/UTF32Encoding.cs
+++ /dev/null
@@ -1,1003 +0,0 @@
-// Licensed to the .NET Foundation under one or more agreements.
-// The .NET Foundation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
-
-//
-// Don't override IsAlwaysNormalized because it is just a Unicode Transformation and could be confused.
-//
-
-namespace System.Text
-{
-
- using System;
- using System.Diagnostics;
- using System.Diagnostics.Contracts;
- using System.Globalization;
- // Encodes text into and out of UTF-32. UTF-32 is a way of writing
- // Unicode characters with a single storage unit (32 bits) per character,
- //
- // The UTF-32 byte order mark is simply the Unicode byte order mark
- // (0x00FEFF) written in UTF-32 (0x0000FEFF or 0xFFFE0000). The byte order
- // mark is used mostly to distinguish UTF-32 text from other encodings, and doesn't
- // switch the byte orderings.
-
- [Serializable]
- public sealed class UTF32Encoding : Encoding
- {
- /*
- words bits UTF-32 representation
- ----- ---- -----------------------------------
- 1 16 00000000 00000000 xxxxxxxx xxxxxxxx
- 2 21 00000000 000xxxxx hhhhhhll llllllll
- ----- ---- -----------------------------------
-
- Surrogate:
- Real Unicode value = (HighSurrogate - 0xD800) * 0x400 + (LowSurrogate - 0xDC00) + 0x10000
- */
-
- // Used by Encoding.UTF32/BigEndianUTF32 for lazy initialization
- // The initialization code will not be run until a static member of the class is referenced
- internal static readonly UTF32Encoding s_default = new UTF32Encoding(bigEndian: false, byteOrderMark: true);
- internal static readonly UTF32Encoding s_bigEndianDefault = new UTF32Encoding(bigEndian: true, byteOrderMark: true);
-
- private bool emitUTF32ByteOrderMark = false;
- private bool isThrowException = false;
- private bool bigEndian = false;
-
-
- public UTF32Encoding(): this(false, true, false)
- {
- }
-
-
- public UTF32Encoding(bool bigEndian, bool byteOrderMark):
- this(bigEndian, byteOrderMark, false)
- {
- }
-
-
- public UTF32Encoding(bool bigEndian, bool byteOrderMark, bool throwOnInvalidCharacters):
- base(bigEndian ? 12001 : 12000)
- {
- this.bigEndian = bigEndian;
- this.emitUTF32ByteOrderMark = byteOrderMark;
- this.isThrowException = throwOnInvalidCharacters;
-
- // Encoding's constructor already did this, but it'll be wrong if we're throwing exceptions
- if (this.isThrowException)
- SetDefaultFallbacks();
- }
-
- internal override void SetDefaultFallbacks()
- {
- // For UTF-X encodings, we use a replacement fallback with an empty string
- if (this.isThrowException)
- {
- this.encoderFallback = EncoderFallback.ExceptionFallback;
- this.decoderFallback = DecoderFallback.ExceptionFallback;
- }
- else
- {
- this.encoderFallback = new EncoderReplacementFallback("\xFFFD");
- this.decoderFallback = new DecoderReplacementFallback("\xFFFD");
- }
- }
-
- // NOTE: Many methods in this class forward to EncodingForwarder for
- // validating arguments/wrapping the unsafe methods in this class
- // which do the actual work. That class contains
- // shared logic for doing this which is used by
- // ASCIIEncoding, EncodingNLS, UnicodeEncoding, UTF32Encoding,
- // UTF7Encoding, and UTF8Encoding.
- // The reason the code is separated out into a static class, rather
- // than a base class which overrides all of these methods for us
- // (which is what EncodingNLS is for internal Encodings) is because
- // that's really more of an implementation detail so it's internal.
- // At the same time, C# doesn't allow a public class subclassing an
- // internal/private one, so we end up having to re-override these
- // methods in all of the public Encodings + EncodingNLS.
-
- // Returns the number of bytes required to encode a range of characters in
- // a character array.
-
- public override int GetByteCount(char[] chars, int index, int count)
- {
- return EncodingForwarder.GetByteCount(this, chars, index, count);
- }
-
- public override int GetByteCount(String s)
- {
- return EncodingForwarder.GetByteCount(this, s);
- }
-
- [CLSCompliant(false)]
- public override unsafe int GetByteCount(char* chars, int count)
- {
- return EncodingForwarder.GetByteCount(this, chars, count);
- }
-
- public override int GetBytes(String s, int charIndex, int charCount,
- byte[] bytes, int byteIndex)
- {
- return EncodingForwarder.GetBytes(this, s, charIndex, charCount, bytes, byteIndex);
- }
-
- // Encodes a range of characters in a character array into a range of bytes
- // in a byte array. An exception occurs if the byte array is not large
- // enough to hold the complete encoding of the characters. The
- // GetByteCount method can be used to determine the exact number of
- // bytes that will be produced for a given range of characters.
- // Alternatively, the GetMaxByteCount method can be used to
- // determine the maximum number of bytes that will be produced for a given
- // number of characters, regardless of the actual character values.
-
- public override int GetBytes(char[] chars, int charIndex, int charCount,
- byte[] bytes, int byteIndex)
- {
- return EncodingForwarder.GetBytes(this, chars, charIndex, charCount, bytes, byteIndex);
- }
-
- [CLSCompliant(false)]
- public override unsafe int GetBytes(char* chars, int charCount, byte* bytes, int byteCount)
- {
- return EncodingForwarder.GetBytes(this, chars, charCount, bytes, byteCount);
- }
-
- // Returns the number of characters produced by decoding a range of bytes
- // in a byte array.
-
- public override int GetCharCount(byte[] bytes, int index, int count)
- {
- return EncodingForwarder.GetCharCount(this, bytes, index, count);
- }
-
- [CLSCompliant(false)]
- public override unsafe int GetCharCount(byte* bytes, int count)
- {
- return EncodingForwarder.GetCharCount(this, bytes, count);
- }
-
- public override int GetChars(byte[] bytes, int byteIndex, int byteCount,
- char[] chars, int charIndex)
- {
- return EncodingForwarder.GetChars(this, bytes, byteIndex, byteCount, chars, charIndex);
- }
-
- [CLSCompliant(false)]
- public unsafe override int GetChars(byte* bytes, int byteCount, char* chars, int charCount)
- {
- return EncodingForwarder.GetChars(this, bytes, byteCount, chars, charCount);
- }
-
- // Returns a string containing the decoded representation of a range of
- // bytes in a byte array.
-
- public override String GetString(byte[] bytes, int index, int count)
- {
- return EncodingForwarder.GetString(this, bytes, index, count);
- }
-
- // End of overridden methods which use EncodingForwarder
-
- internal override unsafe int GetByteCount(char *chars, int count, EncoderNLS encoder)
- {
- Debug.Assert(chars!=null, "[UTF32Encoding.GetByteCount]chars!=null");
- Debug.Assert(count >=0, "[UTF32Encoding.GetByteCount]count >=0");
-
- char* end = chars + count;
- char* charStart = chars;
- int byteCount = 0;
-
- char highSurrogate = '\0';
-
- // For fallback we may need a fallback buffer
- EncoderFallbackBuffer fallbackBuffer = null;
- if (encoder != null)
- {
- highSurrogate = encoder.charLeftOver;
- fallbackBuffer = encoder.FallbackBuffer;
-
- // We mustn't have left over fallback data when counting
- if (fallbackBuffer.Remaining > 0)
- throw new ArgumentException(Environment.GetResourceString("Argument_EncoderFallbackNotEmpty",
- this.EncodingName, encoder.Fallback.GetType()));
- }
- else
- {
- fallbackBuffer = this.encoderFallback.CreateFallbackBuffer();
- }
-
- // Set our internal fallback interesting things.
- fallbackBuffer.InternalInitialize(charStart, end, encoder, false);
-
- char ch;
- TryAgain:
-
- while (((ch = fallbackBuffer.InternalGetNextChar()) != 0) || chars < end)
- {
- // First unwind any fallback
- if (ch == 0)
- {
- // No fallback, just get next char
- ch = *chars;
- chars++;
- }
-
- // Do we need a low surrogate?
- if (highSurrogate != '\0')
- {
- //
- // In previous char, we encounter a high surrogate, so we are expecting a low surrogate here.
- //
- if (Char.IsLowSurrogate(ch))
- {
- // They're all legal
- highSurrogate = '\0';
-
- //
- // One surrogate pair will be translated into 4 bytes UTF32.
- //
-
- byteCount += 4;
- continue;
- }
-
- // We are missing our low surrogate, decrement chars and fallback the high surrogate
- // The high surrogate may have come from the encoder, but nothing else did.
- Debug.Assert(chars > charStart,
- "[UTF32Encoding.GetByteCount]Expected chars to have advanced if no low surrogate");
- chars--;
-
- // Do the fallback
- fallbackBuffer.InternalFallback(highSurrogate, ref chars);
-
- // We're going to fallback the old high surrogate.
- highSurrogate = '\0';
- continue;
-
- }
-
- // Do we have another high surrogate?
- if (Char.IsHighSurrogate(ch))
- {
- //
- // We'll have a high surrogate to check next time.
- //
- highSurrogate = ch;
- continue;
- }
-
- // Check for illegal characters
- if (Char.IsLowSurrogate(ch))
- {
- // We have a leading low surrogate, do the fallback
- fallbackBuffer.InternalFallback(ch, ref chars);
-
- // Try again with fallback buffer
- continue;
- }
-
- // We get to add the character (4 bytes UTF32)
- byteCount += 4;
- }
-
- // May have to do our last surrogate
- if ((encoder == null || encoder.MustFlush) && highSurrogate > 0)
- {
- // We have to do the fallback for the lonely high surrogate
- fallbackBuffer.InternalFallback(highSurrogate, ref chars);
- highSurrogate = (char)0;
- goto TryAgain;
- }
-
- // Check for overflows.
- if (byteCount < 0)
- throw new ArgumentOutOfRangeException(nameof(count), Environment.GetResourceString(
- "ArgumentOutOfRange_GetByteCountOverflow"));
-
- // Shouldn't have anything in fallback buffer for GetByteCount
- // (don't have to check m_throwOnOverflow for count)
- Debug.Assert(fallbackBuffer.Remaining == 0,
- "[UTF32Encoding.GetByteCount]Expected empty fallback buffer at end");
-
- // Return our count
- return byteCount;
- }
-
- internal override unsafe int GetBytes(char *chars, int charCount,
- byte* bytes, int byteCount, EncoderNLS encoder)
- {
- Debug.Assert(chars!=null, "[UTF32Encoding.GetBytes]chars!=null");
- Debug.Assert(bytes!=null, "[UTF32Encoding.GetBytes]bytes!=null");
- Debug.Assert(byteCount >=0, "[UTF32Encoding.GetBytes]byteCount >=0");
- Debug.Assert(charCount >=0, "[UTF32Encoding.GetBytes]charCount >=0");
-
- char* charStart = chars;
- char* charEnd = chars + charCount;
- byte* byteStart = bytes;
- byte* byteEnd = bytes + byteCount;
-
- char highSurrogate = '\0';
-
- // For fallback we may need a fallback buffer
- EncoderFallbackBuffer fallbackBuffer = null;
- if (encoder != null)
- {
- highSurrogate = encoder.charLeftOver;
- fallbackBuffer = encoder.FallbackBuffer;
-
- // We mustn't have left over fallback data when not converting
- if (encoder.m_throwOnOverflow && fallbackBuffer.Remaining > 0)
- throw new ArgumentException(Environment.GetResourceString("Argument_EncoderFallbackNotEmpty",
- this.EncodingName, encoder.Fallback.GetType()));
- }
- else
- {
- fallbackBuffer = this.encoderFallback.CreateFallbackBuffer();
- }
-
- // Set our internal fallback interesting things.
- fallbackBuffer.InternalInitialize(charStart, charEnd, encoder, true);
-
- char ch;
- TryAgain:
-
- while (((ch = fallbackBuffer.InternalGetNextChar()) != 0) || chars < charEnd)
- {
- // First unwind any fallback
- if (ch == 0)
- {
- // No fallback, just get next char
- ch = *chars;
- chars++;
- }
-
- // Do we need a low surrogate?
- if (highSurrogate != '\0')
- {
- //
- // In previous char, we encountered a high surrogate, so we are expecting a low surrogate here.
- //
- if (Char.IsLowSurrogate(ch))
- {
- // Is it a legal one?
- uint iTemp = GetSurrogate(highSurrogate, ch);
- highSurrogate = '\0';
-
- //
- // One surrogate pair will be translated into 4 bytes UTF32.
- //
- if (bytes+3 >= byteEnd)
- {
- // Don't have 4 bytes
- if (fallbackBuffer.bFallingBack)
- {
- fallbackBuffer.MovePrevious(); // Aren't using these 2 fallback chars
- fallbackBuffer.MovePrevious();
- }
- else
- {
- // If we don't have enough room, then either we should've advanced a while
- // or we should have bytes==byteStart and throw below
- Debug.Assert(chars > charStart + 1 || bytes == byteStart,
- "[UnicodeEncoding.GetBytes]Expected chars to have when no room to add surrogate pair");
- chars-=2; // Aren't using those 2 chars
- }
- ThrowBytesOverflow(encoder, bytes == byteStart); // Throw maybe (if no bytes written)
- highSurrogate = (char)0; // Nothing left over (we backed up to start of pair if supplimentary)
- break;
- }
-
- if (bigEndian)
- {
- *(bytes++) = (byte)(0x00);
- *(bytes++) = (byte)(iTemp >> 16); // Implies & 0xFF, which isn't needed cause high are all 0
- *(bytes++) = (byte)(iTemp >> 8); // Implies & 0xFF
- *(bytes++) = (byte)(iTemp); // Implies & 0xFF
- }
- else
- {
- *(bytes++) = (byte)(iTemp); // Implies & 0xFF
- *(bytes++) = (byte)(iTemp >> 8); // Implies & 0xFF
- *(bytes++) = (byte)(iTemp >> 16); // Implies & 0xFF, which isn't needed cause high are all 0
- *(bytes++) = (byte)(0x00);
- }
- continue;
- }
-
- // We are missing our low surrogate, decrement chars and fallback the high surrogate
- // The high surrogate may have come from the encoder, but nothing else did.
- Debug.Assert(chars > charStart,
- "[UTF32Encoding.GetBytes]Expected chars to have advanced if no low surrogate");
- chars--;
-
- // Do the fallback
- fallbackBuffer.InternalFallback(highSurrogate, ref chars);
-
- // We're going to fallback the old high surrogate.
- highSurrogate = '\0';
- continue;
- }
-
- // Do we have another high surrogate?, if so remember it
- if (Char.IsHighSurrogate(ch))
- {
- //
- // We'll have a high surrogate to check next time.
- //
- highSurrogate = ch;
- continue;
- }
-
- // Check for illegal characters (low surrogate)
- if (Char.IsLowSurrogate(ch))
- {
- // We have a leading low surrogate, do the fallback
- fallbackBuffer.InternalFallback(ch, ref chars);
-
- // Try again with fallback buffer
- continue;
- }
-
- // We get to add the character, yippee.
- if (bytes+3 >= byteEnd)
- {
- // Don't have 4 bytes
- if (fallbackBuffer.bFallingBack)
- fallbackBuffer.MovePrevious(); // Aren't using this fallback char
- else
- {
- // Must've advanced already
- Debug.Assert(chars > charStart,
- "[UTF32Encoding.GetBytes]Expected chars to have advanced if normal character");
- chars--; // Aren't using this char
- }
- ThrowBytesOverflow(encoder, bytes == byteStart); // Throw maybe (if no bytes written)
- break; // Didn't throw, stop
- }
-
- if (bigEndian)
- {
- *(bytes++) = (byte)(0x00);
- *(bytes++) = (byte)(0x00);
- *(bytes++) = (byte)((uint)ch >> 8); // Implies & 0xFF
- *(bytes++) = (byte)(ch); // Implies & 0xFF
- }
- else
- {
- *(bytes++) = (byte)(ch); // Implies & 0xFF
- *(bytes++) = (byte)((uint)ch >> 8); // Implies & 0xFF
- *(bytes++) = (byte)(0x00);
- *(bytes++) = (byte)(0x00);
- }
- }
-
- // May have to do our last surrogate
- if ((encoder == null || encoder.MustFlush) && highSurrogate > 0)
- {
- // We have to do the fallback for the lonely high surrogate
- fallbackBuffer.InternalFallback(highSurrogate, ref chars);
- highSurrogate = (char)0;
- goto TryAgain;
- }
-
- // Fix our encoder if we have one
- Debug.Assert(highSurrogate == 0 || (encoder != null && !encoder.MustFlush),
- "[UTF32Encoding.GetBytes]Expected encoder to be flushed.");
-
- if (encoder != null)
- {
- // Remember our left over surrogate (or 0 if flushing)
- encoder.charLeftOver = highSurrogate;
-
- // Need # chars used
- encoder.m_charsUsed = (int)(chars-charStart);
- }
-
- // return the new length
- return (int)(bytes - byteStart);
- }
-
- internal override unsafe int GetCharCount(byte* bytes, int count, DecoderNLS baseDecoder)
- {
- Debug.Assert(bytes!=null, "[UTF32Encoding.GetCharCount]bytes!=null");
- Debug.Assert(count >=0, "[UTF32Encoding.GetCharCount]count >=0");
-
- UTF32Decoder decoder = (UTF32Decoder)baseDecoder;
-
- // None so far!
- int charCount = 0;
- byte* end = bytes + count;
- byte* byteStart = bytes;
-
- // Set up decoder
- int readCount = 0;
- uint iChar = 0;
-
- // For fallback we may need a fallback buffer
- DecoderFallbackBuffer fallbackBuffer = null;
-
- // See if there's anything in our decoder
- if (decoder != null)
- {
- readCount = decoder.readByteCount;
- iChar = (uint)decoder.iChar;
- fallbackBuffer = decoder.FallbackBuffer;
-
- // Shouldn't have anything in fallback buffer for GetCharCount
- // (don't have to check m_throwOnOverflow for chars or count)
- Debug.Assert(fallbackBuffer.Remaining == 0,
- "[UTF32Encoding.GetCharCount]Expected empty fallback buffer at start");
- }
- else
- {
- fallbackBuffer = this.decoderFallback.CreateFallbackBuffer();
- }
-
- // Set our internal fallback interesting things.
- fallbackBuffer.InternalInitialize(byteStart, null);
-
- // Loop through our input, 4 characters at a time!
- while (bytes < end && charCount >= 0)
- {
- // Get our next character
- if(bigEndian)
- {
- // Scoot left and add it to the bottom
- iChar <<= 8;
- iChar += *(bytes++);
- }
- else
- {
- // Scoot right and add it to the top
- iChar >>= 8;
- iChar += (uint)(*(bytes++)) << 24;
- }
-
- readCount++;
-
- // See if we have all the bytes yet
- if (readCount < 4)
- continue;
-
- // Have the bytes
- readCount = 0;
-
- // See if its valid to encode
- if ( iChar > 0x10FFFF || (iChar >= 0xD800 && iChar <= 0xDFFF))
- {
- // Need to fall back these 4 bytes
- byte[] fallbackBytes;
- if (this.bigEndian)
- {
- fallbackBytes = new byte[] {
- unchecked((byte)(iChar>>24)), unchecked((byte)(iChar>>16)),
- unchecked((byte)(iChar>>8)), unchecked((byte)(iChar)) };
- }
- else
- {
- fallbackBytes = new byte[] {
- unchecked((byte)(iChar)), unchecked((byte)(iChar>>8)),
- unchecked((byte)(iChar>>16)), unchecked((byte)(iChar>>24)) };
- }
-
- charCount += fallbackBuffer.InternalFallback(fallbackBytes, bytes);
-
- // Ignore the illegal character
- iChar = 0;
- continue;
- }
-
- // Ok, we have something we can add to our output
- if (iChar >= 0x10000)
- {
- // Surrogates take 2
- charCount++;
- }
-
- // Add the rest of the surrogate or our normal character
- charCount++;
-
- // iChar is back to 0
- iChar = 0;
- }
-
- // See if we have something left over that has to be decoded
- if (readCount > 0 && (decoder == null || decoder.MustFlush))
- {
- // Oops, there's something left over with no place to go.
- byte[] fallbackBytes = new byte[readCount];
- if (this.bigEndian)
- {
- while(readCount > 0)
- {
- fallbackBytes[--readCount] = unchecked((byte)iChar);
- iChar >>= 8;
- }
- }
- else
- {
- while (readCount > 0)
- {
- fallbackBytes[--readCount] = unchecked((byte)(iChar>>24));
- iChar <<= 8;
- }
- }
-
- charCount += fallbackBuffer.InternalFallback(fallbackBytes, bytes);
- }
-
- // Check for overflows.
- if (charCount < 0)
- throw new ArgumentOutOfRangeException(nameof(count), Environment.GetResourceString("ArgumentOutOfRange_GetByteCountOverflow"));
-
- // Shouldn't have anything in fallback buffer for GetCharCount
- // (don't have to check m_throwOnOverflow for chars or count)
- Debug.Assert(fallbackBuffer.Remaining == 0,
- "[UTF32Encoding.GetCharCount]Expected empty fallback buffer at end");
-
- // Return our count
- return charCount;
- }
-
- internal override unsafe int GetChars(byte* bytes, int byteCount,
- char* chars, int charCount, DecoderNLS baseDecoder)
- {
- Debug.Assert(chars!=null, "[UTF32Encoding.GetChars]chars!=null");
- Debug.Assert(bytes!=null, "[UTF32Encoding.GetChars]bytes!=null");
- Debug.Assert(byteCount >=0, "[UTF32Encoding.GetChars]byteCount >=0");
- Debug.Assert(charCount >=0, "[UTF32Encoding.GetChars]charCount >=0");
-
- UTF32Decoder decoder = (UTF32Decoder)baseDecoder;
-
- // None so far!
- char* charStart = chars;
- char* charEnd = chars + charCount;
-
- byte* byteStart = bytes;
- byte* byteEnd = bytes + byteCount;
-
- // See if there's anything in our decoder (but don't clear it yet)
- int readCount = 0;
- uint iChar = 0;
-
- // For fallback we may need a fallback buffer
- DecoderFallbackBuffer fallbackBuffer = null;
-
- // See if there's anything in our decoder
- if (decoder != null)
- {
- readCount = decoder.readByteCount;
- iChar = (uint)decoder.iChar;
- fallbackBuffer = baseDecoder.FallbackBuffer;
-
- // Shouldn't have anything in fallback buffer for GetChars
- // (don't have to check m_throwOnOverflow for chars)
- Debug.Assert(fallbackBuffer.Remaining == 0,
- "[UTF32Encoding.GetChars]Expected empty fallback buffer at start");
- }
- else
- {
- fallbackBuffer = this.decoderFallback.CreateFallbackBuffer();
- }
-
- // Set our internal fallback interesting things.
- fallbackBuffer.InternalInitialize(bytes, chars + charCount);
-
- // Loop through our input, 4 characters at a time!
- while (bytes < byteEnd)
- {
- // Get our next character
- if(bigEndian)
- {
- // Scoot left and add it to the bottom
- iChar <<= 8;
- iChar += *(bytes++);
- }
- else
- {
- // Scoot right and add it to the top
- iChar >>= 8;
- iChar += (uint)(*(bytes++)) << 24;
- }
-
- readCount++;
-
- // See if we have all the bytes yet
- if (readCount < 4)
- continue;
-
- // Have the bytes
- readCount = 0;
-
- // See if its valid to encode
- if ( iChar > 0x10FFFF || (iChar >= 0xD800 && iChar <= 0xDFFF))
- {
- // Need to fall back these 4 bytes
- byte[] fallbackBytes;
- if (this.bigEndian)
- {
- fallbackBytes = new byte[] {
- unchecked((byte)(iChar>>24)), unchecked((byte)(iChar>>16)),
- unchecked((byte)(iChar>>8)), unchecked((byte)(iChar)) };
- }
- else
- {
- fallbackBytes = new byte[] {
- unchecked((byte)(iChar)), unchecked((byte)(iChar>>8)),
- unchecked((byte)(iChar>>16)), unchecked((byte)(iChar>>24)) };
- }
-
- // Chars won't be updated unless this works.
- if (!fallbackBuffer.InternalFallback(fallbackBytes, bytes, ref chars))
- {
- // Couldn't fallback, throw or wait til next time
- // We either read enough bytes for bytes-=4 to work, or we're
- // going to throw in ThrowCharsOverflow because chars == charStart
- Debug.Assert(bytes >= byteStart + 4 || chars == charStart,
- "[UTF32Encoding.GetChars]Expected to have consumed bytes or throw (bad surrogate)");
- bytes-=4; // get back to where we were
- iChar=0; // Remembering nothing
- fallbackBuffer.InternalReset();
- ThrowCharsOverflow(decoder, chars == charStart);// Might throw, if no chars output
- break; // Stop here, didn't throw
- }
-
- // Ignore the illegal character
- iChar = 0;
- continue;
- }
-
-
- // Ok, we have something we can add to our output
- if (iChar >= 0x10000)
- {
- // Surrogates take 2
- if (chars >= charEnd - 1)
- {
- // Throwing or stopping
- // We either read enough bytes for bytes-=4 to work, or we're
- // going to throw in ThrowCharsOverflow because chars == charStart
- Debug.Assert(bytes >= byteStart + 4 || chars == charStart,
- "[UTF32Encoding.GetChars]Expected to have consumed bytes or throw (surrogate)");
- bytes-=4; // get back to where we were
- iChar=0; // Remembering nothing
- ThrowCharsOverflow(decoder, chars == charStart);// Might throw, if no chars output
- break; // Stop here, didn't throw
- }
-
- *(chars++) = GetHighSurrogate(iChar);
- iChar = GetLowSurrogate(iChar);
- }
- // Bounds check for normal character
- else if (chars >= charEnd)
- {
- // Throwing or stopping
- // We either read enough bytes for bytes-=4 to work, or we're
- // going to throw in ThrowCharsOverflow because chars == charStart
- Debug.Assert(bytes >= byteStart + 4 || chars == charStart,
- "[UTF32Encoding.GetChars]Expected to have consumed bytes or throw (normal char)");
- bytes-=4; // get back to where we were
- iChar=0; // Remembering nothing
- ThrowCharsOverflow(decoder, chars == charStart);// Might throw, if no chars output
- break; // Stop here, didn't throw
- }
-
- // Add the rest of the surrogate or our normal character
- *(chars++) = (char)iChar;
-
- // iChar is back to 0
- iChar = 0;
- }
-
- // See if we have something left over that has to be decoded
- if (readCount > 0 && (decoder == null || decoder.MustFlush))
- {
- // Oops, there's something left over with no place to go.
- byte[] fallbackBytes = new byte[readCount];
- int tempCount = readCount;
- if (this.bigEndian)
- {
- while(tempCount > 0)
- {
- fallbackBytes[--tempCount] = unchecked((byte)iChar);
- iChar >>= 8;
- }
- }
- else
- {
- while (tempCount > 0)
- {
- fallbackBytes[--tempCount] = unchecked((byte)(iChar>>24));
- iChar <<= 8;
- }
- }
-
- if (!fallbackBuffer.InternalFallback(fallbackBytes, bytes, ref chars))
- {
- // Couldn't fallback.
- fallbackBuffer.InternalReset();
- ThrowCharsOverflow(decoder, chars == charStart);// Might throw, if no chars output
- // Stop here, didn't throw, backed up, so still nothing in buffer
- }
- else
- {
- // Don't clear our decoder unless we could fall it back.
- // If we caught the if above, then we're a convert() and will catch this next time.
- readCount = 0;
- iChar = 0;
- }
- }
-
- // Remember any left over stuff, clearing buffer as well for MustFlush
- if (decoder != null)
- {
- decoder.iChar = (int)iChar;
- decoder.readByteCount = readCount;
- decoder.m_bytesUsed = (int)(bytes - byteStart);
- }
-
- // Shouldn't have anything in fallback buffer for GetChars
- // (don't have to check m_throwOnOverflow for chars)
- Debug.Assert(fallbackBuffer.Remaining == 0,
- "[UTF32Encoding.GetChars]Expected empty fallback buffer at end");
-
- // Return our count
- return (int)(chars - charStart);
- }
-
-
- private uint GetSurrogate(char cHigh, char cLow)
- {
- return (((uint)cHigh - 0xD800) * 0x400) + ((uint)cLow - 0xDC00) + 0x10000;
- }
-
- private char GetHighSurrogate(uint iChar)
- {
- return (char)((iChar - 0x10000) / 0x400 + 0xD800);
- }
-
- private char GetLowSurrogate(uint iChar)
- {
- return (char)((iChar - 0x10000) % 0x400 + 0xDC00);
- }
-
-
- public override Decoder GetDecoder()
- {
- return new UTF32Decoder(this);
- }
-
-
- public override Encoder GetEncoder()
- {
- return new EncoderNLS(this);
- }
-
-
- public override int GetMaxByteCount(int charCount)
- {
- if (charCount < 0)
- throw new ArgumentOutOfRangeException(nameof(charCount),
- Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
- Contract.EndContractBlock();
-
- // Characters would be # of characters + 1 in case left over high surrogate is ? * max fallback
- long byteCount = (long)charCount + 1;
-
- if (EncoderFallback.MaxCharCount > 1)
- byteCount *= EncoderFallback.MaxCharCount;
-
- // 4 bytes per char
- byteCount *= 4;
-
- if (byteCount > 0x7fffffff)
- throw new ArgumentOutOfRangeException(nameof(charCount), Environment.GetResourceString("ArgumentOutOfRange_GetByteCountOverflow"));
-
- return (int)byteCount;
- }
-
-
- public override int GetMaxCharCount(int byteCount)
- {
- if (byteCount < 0)
- throw new ArgumentOutOfRangeException(nameof(byteCount),
- Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
- Contract.EndContractBlock();
-
- // A supplementary character becomes 2 surrogate characters, so 4 input bytes becomes 2 chars,
- // plus we may have 1 surrogate char left over if the decoder has 3 bytes in it already for a non-bmp char.
- // Have to add another one because 1/2 == 0, but 3 bytes left over could be 2 char surrogate pair
- int charCount = (byteCount / 2) + 2;
-
- // Also consider fallback because our input bytes could be out of range of unicode.
- // Since fallback would fallback 4 bytes at a time, we'll only fall back 1/2 of MaxCharCount.
- if (DecoderFallback.MaxCharCount > 2)
- {
- // Multiply time fallback size
- charCount *= DecoderFallback.MaxCharCount;
-
- // We were already figuring 2 chars per 4 bytes, but fallback will be different #
- charCount /= 2;
- }
-
- if (charCount > 0x7fffffff)
- throw new ArgumentOutOfRangeException(nameof(byteCount), Environment.GetResourceString("ArgumentOutOfRange_GetCharCountOverflow"));
-
- return (int)charCount;
- }
-
-
- public override byte[] GetPreamble()
- {
- if (emitUTF32ByteOrderMark)
- {
- // Allocate new array to prevent users from modifying it.
- if (bigEndian)
- {
- return new byte[4] { 0x00, 0x00, 0xFE, 0xFF };
- }
- else
- {
- return new byte[4] { 0xFF, 0xFE, 0x00, 0x00 }; // 00 00 FE FF
- }
- }
- else
- return EmptyArray<Byte>.Value;
- }
-
-
- public override bool Equals(Object value)
- {
- UTF32Encoding that = value as UTF32Encoding;
- if (that != null)
- {
- return (emitUTF32ByteOrderMark == that.emitUTF32ByteOrderMark) &&
- (bigEndian == that.bigEndian) &&
-// (isThrowException == that.isThrowException) && // same as encoder/decoderfallback being exceptions
- (EncoderFallback.Equals(that.EncoderFallback)) &&
- (DecoderFallback.Equals(that.DecoderFallback));
- }
- return (false);
- }
-
-
- public override int GetHashCode()
- {
- //Not great distribution, but this is relatively unlikely to be used as the key in a hashtable.
- return this.EncoderFallback.GetHashCode() + this.DecoderFallback.GetHashCode() +
- CodePage + (emitUTF32ByteOrderMark?4:0) + (bigEndian?8:0);
- }
-
- [Serializable]
- internal class UTF32Decoder : DecoderNLS
- {
- // Need a place to store any extra bytes we may have picked up
- internal int iChar = 0;
- internal int readByteCount = 0;
-
- public UTF32Decoder(UTF32Encoding encoding) : base(encoding)
- {
- // base calls reset
- }
-
- public override void Reset()
- {
- this.iChar = 0;
- this.readByteCount = 0;
- if (m_fallbackBuffer != null)
- m_fallbackBuffer.Reset();
- }
-
- // Anything left in our decoder?
- internal override bool HasState
- {
- get
- {
- // ReadByteCount is our flag. (iChar==0 doesn't mean much).
- return (this.readByteCount != 0);
- }
- }
- }
- }
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-16 17:53:42 +0000