|
// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
namespace System.Text
{
using System;
using System.Runtime.Serialization;
using System.Security.Permissions;
using System.Diagnostics.Contracts;
// ASCIIEncoding
//
// Note that ASCIIEncoding is optomized with no best fit and ? for fallback.
// It doesn't come in other flavors.
//
// Note: ASCIIEncoding is the only encoding that doesn't do best fit (windows has best fit).
//
// Note: IsAlwaysNormalized remains false because 1/2 the code points are unassigned, so they'd
// use fallbacks, and we cannot guarantee that fallbacks are normalized.
//
[Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public class ASCIIEncoding : Encoding
{
public ASCIIEncoding() : base(Encoding.CodePageASCII)
{
}
internal override void SetDefaultFallbacks()
{
// For ASCIIEncoding we just use default replacement fallback
this.encoderFallback = EncoderFallback.ReplacementFallback;
this.decoderFallback = DecoderFallback.ReplacementFallback;
}
//
// WARNING: GetByteCount(string chars), GetBytes(string chars,...), and GetString(byte[] byteIndex...)
// WARNING: have different variable names than EncodingNLS.cs, so this can't just be cut & pasted,
// WARNING: or it'll break VB's way of calling these.
//
// The following methods are copied from EncodingNLS.cs.
// Unfortunately EncodingNLS.cs is internal and we're public, so we have to reimpliment them here.
// These should be kept in sync for the following classes:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
//
// Returns the number of bytes required to encode a range of characters in
// a character array.
//
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
// parent method is safe
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetByteCount(char[] chars, int index, int count)
{
// Validate input parameters
if (chars == null)
throw new ArgumentNullException("chars",
Environment.GetResourceString("ArgumentNull_Array"));
if (index < 0 || count < 0)
throw new ArgumentOutOfRangeException((index<0 ? "index" : "count"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (chars.Length - index < count)
throw new ArgumentOutOfRangeException("chars",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
Contract.EndContractBlock();
// If no input, return 0, avoid fixed empty array problem
if (chars.Length == 0)
return 0;
// Just call the pointer version
fixed (char* pChars = chars)
return GetByteCount(pChars + index, count, null);
}
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
// parent method is safe
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetByteCount(String chars)
{
// Validate input
if (chars==null)
throw new ArgumentNullException("chars");
Contract.EndContractBlock();
fixed (char* pChars = chars)
return GetByteCount(pChars, chars.Length, null);
}
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
[System.Security.SecurityCritical] // auto-generated
[CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
public override unsafe int GetByteCount(char* chars, int count)
{
// Validate Parameters
if (chars == null)
throw new ArgumentNullException("chars",
Environment.GetResourceString("ArgumentNull_Array"));
if (count < 0)
throw new ArgumentOutOfRangeException("count",
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
// Call it with empty encoder
return GetByteCount(chars, count, null);
}
// Parent method is safe.
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetBytes(String chars, int charIndex, int charCount,
byte[] bytes, int byteIndex)
{
if (chars == null || bytes == null)
throw new ArgumentNullException((chars == null ? "chars" : "bytes"),
Environment.GetResourceString("ArgumentNull_Array"));
if (charIndex < 0 || charCount < 0)
throw new ArgumentOutOfRangeException((charIndex<0 ? "charIndex" : "charCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (chars.Length - charIndex < charCount)
throw new ArgumentOutOfRangeException("chars",
Environment.GetResourceString("ArgumentOutOfRange_IndexCount"));
if (byteIndex < 0 || byteIndex > bytes.Length)
throw new ArgumentOutOfRangeException("byteIndex",
Environment.GetResourceString("ArgumentOutOfRange_Index"));
Contract.EndContractBlock();
int byteCount = bytes.Length - byteIndex;
// Fixed doesn't like empty byte arrays
if (bytes.Length == 0)
bytes = new byte[1];
fixed (char* pChars = chars)
fixed ( byte* pBytes = bytes)
return GetBytes(pChars + charIndex, charCount,
pBytes + byteIndex, byteCount, null);
}
// 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.
//
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
// parent method is safe
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetBytes(char[] chars, int charIndex, int charCount,
byte[] bytes, int byteIndex)
{
// Validate parameters
if (chars == null || bytes == null)
throw new ArgumentNullException((chars == null ? "chars" : "bytes"),
Environment.GetResourceString("ArgumentNull_Array"));
if (charIndex < 0 || charCount < 0)
throw new ArgumentOutOfRangeException((charIndex<0 ? "charIndex" : "charCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (chars.Length - charIndex < charCount)
throw new ArgumentOutOfRangeException("chars",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
if (byteIndex < 0 || byteIndex > bytes.Length)
throw new ArgumentOutOfRangeException("byteIndex",
Environment.GetResourceString("ArgumentOutOfRange_Index"));
Contract.EndContractBlock();
// If nothing to encode return 0, avoid fixed problem
if (chars.Length == 0)
return 0;
// Just call pointer version
int byteCount = bytes.Length - byteIndex;
// Fixed doesn't like empty byte arrays
if (bytes.Length == 0)
bytes = new byte[1];
fixed (char* pChars = chars)
fixed (byte* pBytes = bytes)
// Remember that byteCount is # to decode, not size of array.
return GetBytes(pChars + charIndex, charCount,
pBytes + byteIndex, byteCount, null);
}
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
[System.Security.SecurityCritical] // auto-generated
[CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
public override unsafe int GetBytes(char* chars, int charCount, byte* bytes, int byteCount)
{
// Validate Parameters
if (bytes == null || chars == null)
throw new ArgumentNullException(bytes == null ? "bytes" : "chars",
Environment.GetResourceString("ArgumentNull_Array"));
if (charCount < 0 || byteCount < 0)
throw new ArgumentOutOfRangeException((charCount<0 ? "charCount" : "byteCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
return GetBytes(chars, charCount, bytes, byteCount, null);
}
// Returns the number of characters produced by decoding a range of bytes
// in a byte array.
//
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
// parent method is safe
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetCharCount(byte[] bytes, int index, int count)
{
// Validate Parameters
if (bytes == null)
throw new ArgumentNullException("bytes",
Environment.GetResourceString("ArgumentNull_Array"));
if (index < 0 || count < 0)
throw new ArgumentOutOfRangeException((index<0 ? "index" : "count"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (bytes.Length - index < count)
throw new ArgumentOutOfRangeException("bytes",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
Contract.EndContractBlock();
// If no input just return 0, fixed doesn't like 0 length arrays
if (bytes.Length == 0)
return 0;
// Just call pointer version
fixed (byte* pBytes = bytes)
return GetCharCount(pBytes + index, count, null);
}
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
[System.Security.SecurityCritical] // auto-generated
[CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
public override unsafe int GetCharCount(byte* bytes, int count)
{
// Validate Parameters
if (bytes == null)
throw new ArgumentNullException("bytes",
Environment.GetResourceString("ArgumentNull_Array"));
if (count < 0)
throw new ArgumentOutOfRangeException("count",
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
return GetCharCount(bytes, count, null);
}
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
// parent method is safe
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetChars(byte[] bytes, int byteIndex, int byteCount,
char[] chars, int charIndex)
{
// Validate Parameters
if (bytes == null || chars == null)
throw new ArgumentNullException(bytes == null ? "bytes" : "chars",
Environment.GetResourceString("ArgumentNull_Array"));
if (byteIndex < 0 || byteCount < 0)
throw new ArgumentOutOfRangeException((byteIndex<0 ? "byteIndex" : "byteCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if ( bytes.Length - byteIndex < byteCount)
throw new ArgumentOutOfRangeException("bytes",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
if (charIndex < 0 || charIndex > chars.Length)
throw new ArgumentOutOfRangeException("charIndex",
Environment.GetResourceString("ArgumentOutOfRange_Index"));
Contract.EndContractBlock();
// If no input, return 0 & avoid fixed problem
if (bytes.Length == 0)
return 0;
// Just call pointer version
int charCount = chars.Length - charIndex;
// Fixed doesn't like empty char arrays
if (chars.Length == 0)
chars = new char[1];
fixed (byte* pBytes = bytes)
fixed (char* pChars = chars)
// Remember that charCount is # to decode, not size of array
return GetChars(pBytes + byteIndex, byteCount,
pChars + charIndex, charCount, null);
}
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
[System.Security.SecurityCritical] // auto-generated
[CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
public unsafe override int GetChars(byte* bytes, int byteCount, char* chars, int charCount)
{
// Validate Parameters
if (bytes == null || chars == null)
throw new ArgumentNullException(bytes == null ? "bytes" : "chars",
Environment.GetResourceString("ArgumentNull_Array"));
if (charCount < 0 || byteCount < 0)
throw new ArgumentOutOfRangeException((charCount<0 ? "charCount" : "byteCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
return GetChars(bytes, byteCount, chars, charCount, null);
}
// Returns a string containing the decoded representation of a range of
// bytes in a byte array.
//
// All of our public Encodings that don't use EncodingNLS must have this (including EncodingNLS)
// So if you fix this, fix the others. Currently those include:
// EncodingNLS, UTF7Encoding, UTF8Encoding, UTF32Encoding, ASCIIEncoding, UnicodeEncoding
// parent method is safe
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe String GetString(byte[] bytes, int byteIndex, int byteCount)
{
// Validate Parameters
if (bytes == null)
throw new ArgumentNullException("bytes",
Environment.GetResourceString("ArgumentNull_Array"));
if (byteIndex < 0 || byteCount < 0)
throw new ArgumentOutOfRangeException((byteIndex < 0 ? "byteIndex" : "byteCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (bytes.Length - byteIndex < byteCount)
throw new ArgumentOutOfRangeException("bytes",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
Contract.EndContractBlock();
// Avoid problems with empty input buffer
if (bytes.Length == 0) return String.Empty;
fixed (byte* pBytes = bytes)
return String.CreateStringFromEncoding(
pBytes + byteIndex, byteCount, this);
}
//
// End of standard methods copied from EncodingNLS.cs
//
// GetByteCount
// Note: We start by assuming that the output will be the same as count. Having
// an encoder or fallback may change that assumption
[System.Security.SecurityCritical] // auto-generated
internal override unsafe int GetByteCount(char* chars, int charCount, EncoderNLS encoder)
{
// Just need to ASSERT, this is called by something else internal that checked parameters already
Contract.Assert(charCount >= 0, "[ASCIIEncoding.GetByteCount]count is negative");
Contract.Assert(chars != null, "[ASCIIEncoding.GetByteCount]chars is null");
// Assert because we shouldn't be able to have a null encoder.
Contract.Assert(encoderFallback != null, "[ASCIIEncoding.GetByteCount]Attempting to use null fallback encoder");
char charLeftOver = (char)0;
EncoderReplacementFallback fallback = null;
// Start by assuming default count, then +/- for fallback characters
char* charEnd = chars + charCount;
// For fallback we may need a fallback buffer, we know we aren't default fallback.
EncoderFallbackBuffer fallbackBuffer = null;
if (encoder != null)
{
charLeftOver = encoder.charLeftOver;
Contract.Assert(charLeftOver == 0 || Char.IsHighSurrogate(charLeftOver),
"[ASCIIEncoding.GetByteCount]leftover character should be high surrogate");
fallback = encoder.Fallback as EncoderReplacementFallback;
// We mustn't have left over fallback data when counting
if (encoder.InternalHasFallbackBuffer)
{
// We always need the fallback buffer in get bytes so we can flush any remaining ones if necessary
fallbackBuffer = encoder.FallbackBuffer;
if (fallbackBuffer.Remaining > 0 && encoder.m_throwOnOverflow)
throw new ArgumentException(Environment.GetResourceString("Argument_EncoderFallbackNotEmpty",
this.EncodingName, encoder.Fallback.GetType()));
// Set our internal fallback interesting things.
fallbackBuffer.InternalInitialize(chars, charEnd, encoder, false);
}
// Verify that we have no fallbackbuffer, for ASCII its always empty, so just assert
Contract.Assert(!encoder.m_throwOnOverflow || !encoder.InternalHasFallbackBuffer ||
encoder.FallbackBuffer.Remaining == 0,
"[ASCIICodePageEncoding.GetByteCount]Expected empty fallback buffer");
// if (encoder.InternalHasFallbackBuffer && encoder.FallbackBuffer.Remaining > 0)
// throw new ArgumentException(Environment.GetResourceString("Argument_EncoderFallbackNotEmpty",
// this.EncodingName, encoder.Fallback.GetType()));
}
else
{
fallback = this.EncoderFallback as EncoderReplacementFallback;
}
// If we have an encoder AND we aren't using default fallback,
// then we may have a complicated count.
if (fallback != null && fallback.MaxCharCount == 1)
{
// Replacement fallback encodes surrogate pairs as two ?? (or two whatever), so return size is always
// same as input size.
// Note that no existing SBCS code pages map code points to supplimentary characters, so this is easy.
// We could however have 1 extra byte if the last call had an encoder and a funky fallback and
// if we don't use the funky fallback this time.
// Do we have an extra char left over from last time?
if (charLeftOver > 0)
charCount++;
return (charCount);
}
// Count is more complicated if you have a funky fallback
// For fallback we may need a fallback buffer, we know we're not default fallback
int byteCount = 0;
// We may have a left over character from last time, try and process it.
if (charLeftOver > 0)
{
Contract.Assert(Char.IsHighSurrogate(charLeftOver), "[ASCIIEncoding.GetByteCount]leftover character should be high surrogate");
Contract.Assert(encoder != null, "[ASCIIEncoding.GetByteCount]Expected encoder");
// Since left over char was a surrogate, it'll have to be fallen back.
// Get Fallback
fallbackBuffer = encoder.FallbackBuffer;
fallbackBuffer.InternalInitialize(chars, charEnd, encoder, false);
// This will fallback a pair if *chars is a low surrogate
fallbackBuffer.InternalFallback(charLeftOver, ref chars);
}
// Now we may have fallback char[] already from the encoder
// Go ahead and do it, including the fallback.
char ch;
while ((ch = (fallbackBuffer == null) ? '\0' : fallbackBuffer.InternalGetNextChar()) != 0 ||
chars < charEnd)
{
// First unwind any fallback
if (ch == 0)
{
// No fallback, just get next char
ch = *chars;
chars++;
}
// Check for fallback, this'll catch surrogate pairs too.
// no chars >= 0x80 are allowed.
if (ch > 0x7f)
{
if (fallbackBuffer == null)
{
// Initialize the buffer
if (encoder == null)
fallbackBuffer = this.encoderFallback.CreateFallbackBuffer();
else
fallbackBuffer = encoder.FallbackBuffer;
fallbackBuffer.InternalInitialize(charEnd - charCount, charEnd, encoder, false);
}
// Get Fallback
fallbackBuffer.InternalFallback(ch, ref chars);
continue;
}
// We'll use this one
byteCount++;
}
Contract.Assert(fallbackBuffer == null || fallbackBuffer.Remaining == 0,
"[ASCIIEncoding.GetByteCount]Expected Empty fallback buffer");
return byteCount;
}
[System.Security.SecurityCritical] // auto-generated
internal override unsafe int GetBytes(char* chars, int charCount,
byte* bytes, int byteCount, EncoderNLS encoder)
{
// Just need to ASSERT, this is called by something else internal that checked parameters already
Contract.Assert(bytes != null, "[ASCIIEncoding.GetBytes]bytes is null");
Contract.Assert(byteCount >= 0, "[ASCIIEncoding.GetBytes]byteCount is negative");
Contract.Assert(chars != null, "[ASCIIEncoding.GetBytes]chars is null");
Contract.Assert(charCount >= 0, "[ASCIIEncoding.GetBytes]charCount is negative");
// Assert because we shouldn't be able to have a null encoder.
Contract.Assert(encoderFallback != null, "[ASCIIEncoding.GetBytes]Attempting to use null encoder fallback");
// Get any left over characters
char charLeftOver = (char)0;
EncoderReplacementFallback fallback = null;
// For fallback we may need a fallback buffer, we know we aren't default fallback.
EncoderFallbackBuffer fallbackBuffer = null;
// prepare our end
char* charEnd = chars + charCount;
byte* byteStart = bytes;
char* charStart = chars;
if (encoder != null)
{
charLeftOver = encoder.charLeftOver;
fallback = encoder.Fallback as EncoderReplacementFallback;
// We mustn't have left over fallback data when counting
if (encoder.InternalHasFallbackBuffer)
{
// We always need the fallback buffer in get bytes so we can flush any remaining ones if necessary
fallbackBuffer = encoder.FallbackBuffer;
if (fallbackBuffer.Remaining > 0 && encoder.m_throwOnOverflow)
throw new ArgumentException(Environment.GetResourceString("Argument_EncoderFallbackNotEmpty",
this.EncodingName, encoder.Fallback.GetType()));
// Set our internal fallback interesting things.
fallbackBuffer.InternalInitialize(charStart, charEnd, encoder, true);
}
Contract.Assert(charLeftOver == 0 || Char.IsHighSurrogate(charLeftOver),
"[ASCIIEncoding.GetBytes]leftover character should be high surrogate");
// Verify that we have no fallbackbuffer, for ASCII its always empty, so just assert
Contract.Assert(!encoder.m_throwOnOverflow || !encoder.InternalHasFallbackBuffer ||
encoder.FallbackBuffer.Remaining == 0,
"[ASCIICodePageEncoding.GetBytes]Expected empty fallback buffer");
// if (encoder.m_throwOnOverflow && encoder.InternalHasFallbackBuffer &&
// encoder.FallbackBuffer.Remaining > 0)
// throw new ArgumentException(Environment.GetResourceString("Argument_EncoderFallbackNotEmpty",
// this.EncodingName, encoder.Fallback.GetType()));
}
else
{
fallback = this.EncoderFallback as EncoderReplacementFallback;
}
// See if we do the fast default or slightly slower fallback
if (fallback != null && fallback.MaxCharCount == 1)
{
// Fast version
char cReplacement = fallback.DefaultString[0];
// Check for replacements in range, otherwise fall back to slow version.
if (cReplacement <= (char)0x7f)
{
// We should have exactly as many output bytes as input bytes, unless there's a left
// over character, in which case we may need one more.
// If we had a left over character will have to add a ? (This happens if they had a funky
// fallback last time, but not this time.) (We can't spit any out though
// because with fallback encoder each surrogate is treated as a seperate code point)
if (charLeftOver > 0)
{
// Have to have room
// Throw even if doing no throw version because this is just 1 char,
// so buffer will never be big enough
if (byteCount == 0)
ThrowBytesOverflow(encoder, true);
// This'll make sure we still have more room and also make sure our return value is correct.
*(bytes++) = (byte)cReplacement;
byteCount--; // We used one of the ones we were counting.
}
// This keeps us from overrunning our output buffer
if (byteCount < charCount)
{
// Throw or make buffer smaller?
ThrowBytesOverflow(encoder, byteCount < 1);
// Just use what we can
charEnd = chars + byteCount;
}
// We just do a quick copy
while (chars < charEnd)
{
char ch2 = *(chars++);
if (ch2 >= 0x0080) *(bytes++) = (byte)cReplacement;
else *(bytes++) = unchecked((byte)(ch2));
}
// Clear encoder
if (encoder != null)
{
encoder.charLeftOver = (char)0;
encoder.m_charsUsed = (int)(chars-charStart);
}
return (int)(bytes - byteStart);
}
}
// Slower version, have to do real fallback.
// prepare our end
byte* byteEnd = bytes + byteCount;
// We may have a left over character from last time, try and process it.
if (charLeftOver > 0)
{
// Initialize the buffer
Contract.Assert(encoder != null,
"[ASCIIEncoding.GetBytes]Expected non null encoder if we have surrogate left over");
fallbackBuffer = encoder.FallbackBuffer;
fallbackBuffer.InternalInitialize(chars, charEnd, encoder, true);
// Since left over char was a surrogate, it'll have to be fallen back.
// Get Fallback
// This will fallback a pair if *chars is a low surrogate
fallbackBuffer.InternalFallback(charLeftOver, ref chars);
}
// Now we may have fallback char[] already from the encoder
// Go ahead and do it, including the fallback.
char ch;
while ((ch = (fallbackBuffer == null) ? '\0' : fallbackBuffer.InternalGetNextChar()) != 0 ||
chars < charEnd)
{
// First unwind any fallback
if (ch == 0)
{
// No fallback, just get next char
ch = *chars;
chars++;
}
// Check for fallback, this'll catch surrogate pairs too.
// All characters >= 0x80 must fall back.
if (ch > 0x7f)
{
// Initialize the buffer
if (fallbackBuffer == null)
{
if (encoder == null)
fallbackBuffer = this.encoderFallback.CreateFallbackBuffer();
else
fallbackBuffer = encoder.FallbackBuffer;
fallbackBuffer.InternalInitialize(charEnd - charCount, charEnd, encoder, true);
}
// Get Fallback
fallbackBuffer.InternalFallback(ch, ref chars);
// Go ahead & continue (& do the fallback)
continue;
}
// We'll use this one
// Bounds check
if (bytes >= byteEnd)
{
// didn't use this char, we'll throw or use buffer
if (fallbackBuffer == null || fallbackBuffer.bFallingBack == false)
{
Contract.Assert(chars > charStart || bytes == byteStart,
"[ASCIIEncoding.GetBytes]Expected chars to have advanced already.");
chars--; // don't use last char
}
else
fallbackBuffer.MovePrevious();
// Are we throwing or using buffer?
ThrowBytesOverflow(encoder, bytes == byteStart); // throw?
break; // don't throw, stop
}
// Go ahead and add it
*bytes = unchecked((byte)ch);
bytes++;
}
// Need to do encoder stuff
if (encoder != null)
{
// Fallback stuck it in encoder if necessary, but we have to clear MustFlush cases
if (fallbackBuffer != null && !fallbackBuffer.bUsedEncoder)
// Clear it in case of MustFlush
encoder.charLeftOver = (char)0;
// Set our chars used count
encoder.m_charsUsed = (int)(chars - charStart);
}
Contract.Assert(fallbackBuffer == null || fallbackBuffer.Remaining == 0 ||
(encoder != null && !encoder.m_throwOnOverflow ),
"[ASCIIEncoding.GetBytes]Expected Empty fallback buffer at end");
return (int)(bytes - byteStart);
}
// This is internal and called by something else,
[System.Security.SecurityCritical] // auto-generated
internal override unsafe int GetCharCount(byte* bytes, int count, DecoderNLS decoder)
{
// Just assert, we're called internally so these should be safe, checked already
Contract.Assert(bytes != null, "[ASCIIEncoding.GetCharCount]bytes is null");
Contract.Assert(count >= 0, "[ASCIIEncoding.GetCharCount]byteCount is negative");
// ASCII doesn't do best fit, so don't have to check for it, find out which decoder fallback we're using
DecoderReplacementFallback fallback = null;
if (decoder == null)
fallback = this.DecoderFallback as DecoderReplacementFallback;
else
{
fallback = decoder.Fallback as DecoderReplacementFallback;
Contract.Assert(!decoder.m_throwOnOverflow || !decoder.InternalHasFallbackBuffer ||
decoder.FallbackBuffer.Remaining == 0,
"[ASCIICodePageEncoding.GetCharCount]Expected empty fallback buffer");
}
if (fallback != null && fallback.MaxCharCount == 1)
{
// Just return length, SBCS stay the same length because they don't map to surrogate
// pairs and we don't have a decoder fallback.
return count;
}
// Only need decoder fallback buffer if not using default replacement fallback, no best fit for ASCII
DecoderFallbackBuffer fallbackBuffer = null;
// Have to do it the hard way.
// Assume charCount will be == count
int charCount = count;
byte[] byteBuffer = new byte[1];
// Do it our fast way
byte* byteEnd = bytes + count;
// Quick loop
while (bytes < byteEnd)
{
// Faster if don't use *bytes++;
byte b = *bytes;
bytes++;
// If unknown we have to do fallback count
if (b >= 0x80)
{
if (fallbackBuffer == null)
{
if (decoder == null)
fallbackBuffer = this.DecoderFallback.CreateFallbackBuffer();
else
fallbackBuffer = decoder.FallbackBuffer;
fallbackBuffer.InternalInitialize(byteEnd - count, null);
}
// Use fallback buffer
byteBuffer[0] = b;
charCount--; // Have to unreserve the one we already allocated for b
charCount += fallbackBuffer.InternalFallback(byteBuffer, bytes);
}
}
// Fallback buffer must be empty
Contract.Assert(fallbackBuffer == null || fallbackBuffer.Remaining == 0,
"[ASCIIEncoding.GetCharCount]Expected Empty fallback buffer");
// Converted sequence is same length as input
return charCount;
}
[System.Security.SecurityCritical] // auto-generated
internal override unsafe int GetChars(byte* bytes, int byteCount,
char* chars, int charCount, DecoderNLS decoder)
{
// Just need to ASSERT, this is called by something else internal that checked parameters already
Contract.Assert(bytes != null, "[ASCIIEncoding.GetChars]bytes is null");
Contract.Assert(byteCount >= 0, "[ASCIIEncoding.GetChars]byteCount is negative");
Contract.Assert(chars != null, "[ASCIIEncoding.GetChars]chars is null");
Contract.Assert(charCount >= 0, "[ASCIIEncoding.GetChars]charCount is negative");
// Do it fast way if using ? replacement fallback
byte* byteEnd = bytes + byteCount;
byte* byteStart = bytes;
char* charStart = chars;
// Note: ASCII doesn't do best fit, but we have to fallback if they use something > 0x7f
// Only need decoder fallback buffer if not using ? fallback.
// ASCII doesn't do best fit, so don't have to check for it, find out which decoder fallback we're using
DecoderReplacementFallback fallback = null;
if (decoder == null)
fallback = this.DecoderFallback as DecoderReplacementFallback;
else
{
fallback = decoder.Fallback as DecoderReplacementFallback;
Contract.Assert(!decoder.m_throwOnOverflow || !decoder.InternalHasFallbackBuffer ||
decoder.FallbackBuffer.Remaining == 0,
"[ASCIICodePageEncoding.GetChars]Expected empty fallback buffer");
}
if (fallback != null && fallback.MaxCharCount == 1)
{
// Try it the fast way
char replacementChar = fallback.DefaultString[0];
// Need byteCount chars, otherwise too small buffer
if (charCount < byteCount)
{
// Need at least 1 output byte, throw if must throw
ThrowCharsOverflow(decoder, charCount < 1);
// Not throwing, use what we can
byteEnd = bytes + charCount;
}
// Quick loop, just do '?' replacement because we don't have fallbacks for decodings.
while (bytes < byteEnd)
{
byte b = *(bytes++);
if (b >= 0x80)
// This is an invalid byte in the ASCII encoding.
*(chars++) = replacementChar;
else
*(chars++) = unchecked((char)b);
}
// bytes & chars used are the same
if (decoder != null)
decoder.m_bytesUsed = (int)(bytes - byteStart);
return (int)(chars - charStart);
}
// Slower way's going to need a fallback buffer
DecoderFallbackBuffer fallbackBuffer = null;
byte[] byteBuffer = new byte[1];
char* charEnd = chars + charCount;
// Not quite so fast loop
while (bytes < byteEnd)
{
// Faster if don't use *bytes++;
byte b = *(bytes);
bytes++;
if (b >= 0x80)
{
// This is an invalid byte in the ASCII encoding.
if (fallbackBuffer == null)
{
if (decoder == null)
fallbackBuffer = this.DecoderFallback.CreateFallbackBuffer();
else
fallbackBuffer = decoder.FallbackBuffer;
fallbackBuffer.InternalInitialize(byteEnd - byteCount, charEnd);
}
// Use fallback buffer
byteBuffer[0] = b;
// Note that chars won't get updated unless this succeeds
if (!fallbackBuffer.InternalFallback(byteBuffer, bytes, ref chars))
{
// May or may not throw, but we didn't get this byte
Contract.Assert(bytes > byteStart || chars == charStart,
"[ASCIIEncoding.GetChars]Expected bytes to have advanced already (fallback case)");
bytes--; // unused byte
fallbackBuffer.InternalReset(); // Didn't fall this back
ThrowCharsOverflow(decoder, chars == charStart); // throw?
break; // don't throw, but stop loop
}
}
else
{
// Make sure we have buffer space
if (chars >= charEnd)
{
Contract.Assert(bytes > byteStart || chars == charStart,
"[ASCIIEncoding.GetChars]Expected bytes to have advanced already (normal case)");
bytes--; // unused byte
ThrowCharsOverflow(decoder, chars == charStart); // throw?
break; // don't throw, but stop loop
}
*(chars) = unchecked((char)b);
chars++;
}
}
// Might have had decoder fallback stuff.
if (decoder != null)
decoder.m_bytesUsed = (int)(bytes - byteStart);
// Expect Empty fallback buffer for GetChars
Contract.Assert(fallbackBuffer == null || fallbackBuffer.Remaining == 0,
"[ASCIIEncoding.GetChars]Expected Empty fallback buffer");
return (int)(chars - charStart);
}
public override int GetMaxByteCount(int charCount)
{
if (charCount < 0)
throw new ArgumentOutOfRangeException("charCount",
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
// Characters would be # of characters + 1 in case high surrogate is ? * max fallback
long byteCount = (long)charCount + 1;
if (EncoderFallback.MaxCharCount > 1)
byteCount *= EncoderFallback.MaxCharCount;
// 1 to 1 for most characters. Only surrogates with fallbacks have less.
if (byteCount > 0x7fffffff)
throw new ArgumentOutOfRangeException("charCount", Environment.GetResourceString("ArgumentOutOfRange_GetByteCountOverflow"));
return (int)byteCount;
}
public override int GetMaxCharCount(int byteCount)
{
if (byteCount < 0)
throw new ArgumentOutOfRangeException("byteCount",
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
// Just return length, SBCS stay the same length because they don't map to surrogate
long charCount = (long)byteCount;
// 1 to 1 for most characters. Only surrogates with fallbacks have less, unknown fallbacks could be longer.
if (DecoderFallback.MaxCharCount > 1)
charCount *= DecoderFallback.MaxCharCount;
if (charCount > 0x7fffffff)
throw new ArgumentOutOfRangeException("byteCount", Environment.GetResourceString("ArgumentOutOfRange_GetCharCountOverflow"));
return (int)charCount;
}
// True if and only if the encoding only uses single byte code points. (Ie, ASCII, 1252, etc)
[System.Runtime.InteropServices.ComVisible(false)]
public override bool IsSingleByte
{
get
{
return true;
}
}
[System.Runtime.InteropServices.ComVisible(false)]
public override Decoder GetDecoder()
{
return new DecoderNLS(this);
}
[System.Runtime.InteropServices.ComVisible(false)]
public override Encoder GetEncoder()
{
return new EncoderNLS(this);
}
}
}
|