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// ==++==
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// ==--==
namespace System.Text
{
using System.Runtime.Serialization;
using System.Security.Permissions;
using System.Text;
using System;
using System.Diagnostics.Contracts;
// An Encoder is used to encode a sequence of blocks of characters into
// a sequence of blocks of bytes. Following instantiation of an encoder,
// sequential blocks of characters are converted into blocks of bytes through
// calls to the GetBytes method. The encoder maintains state between the
// conversions, allowing it to correctly encode character sequences that span
// adjacent blocks.
//
// Instances of specific implementations of the Encoder abstract base
// class are typically obtained through calls to the GetEncoder method
// of Encoding objects.
//
[Serializable]
internal class EncoderNLS : Encoder, ISerializable
{
// Need a place for the last left over character, most of our encodings use this
internal char charLeftOver;
protected Encoding m_encoding;
[NonSerialized] protected bool m_mustFlush;
[NonSerialized] internal bool m_throwOnOverflow;
[NonSerialized] internal int m_charsUsed;
#region Serialization
// Constructor called by serialization. called during deserialization.
internal EncoderNLS(SerializationInfo info, StreamingContext context)
{
throw new NotSupportedException(
String.Format(
System.Globalization.CultureInfo.CurrentCulture,
Environment.GetResourceString("NotSupported_TypeCannotDeserialized"), this.GetType()));
}
#if FEATURE_SERIALIZATION
// ISerializable implementation. called during serialization.
[System.Security.SecurityCritical] // auto-generated_required
void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
{
SerializeEncoder(info);
info.AddValue("encoding", this.m_encoding);
info.AddValue("charLeftOver", this.charLeftOver);
info.SetType(typeof(Encoding.DefaultEncoder));
}
#endif
#endregion Serialization
internal EncoderNLS(Encoding encoding)
{
this.m_encoding = encoding;
this.m_fallback = this.m_encoding.EncoderFallback;
this.Reset();
}
// This one is used when deserializing (like UTF7Encoding.Encoder)
internal EncoderNLS()
{
this.m_encoding = null;
this.Reset();
}
public override void Reset()
{
this.charLeftOver = (char)0;
if (m_fallbackBuffer != null)
m_fallbackBuffer.Reset();
}
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetByteCount(char[] chars, int index, int count, bool flush)
{
// 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();
// Avoid empty input problem
if (chars.Length == 0)
chars = new char[1];
// Just call the pointer version
int result = -1;
fixed (char* pChars = chars)
{
result = GetByteCount(pChars + index, count, flush);
}
return result;
}
[System.Security.SecurityCritical] // auto-generated
public unsafe override int GetByteCount(char* chars, int count, bool flush)
{
// Validate input 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();
this.m_mustFlush = flush;
this.m_throwOnOverflow = true;
return m_encoding.GetByteCount(chars, count, this);
}
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe int GetBytes(char[] chars, int charIndex, int charCount,
byte[] bytes, int byteIndex, bool flush)
{
// 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 (chars.Length == 0)
chars = new char[1];
int byteCount = bytes.Length - byteIndex;
if (bytes.Length == 0)
bytes = new byte[1];
// Just call pointer version
fixed (char* pChars = chars)
fixed (byte* pBytes = bytes)
// Remember that charCount is # to decode, not size of array.
return GetBytes(pChars + charIndex, charCount,
pBytes + byteIndex, byteCount, flush);
}
[System.Security.SecurityCritical] // auto-generated
public unsafe override int GetBytes(char* chars, int charCount, byte* bytes, int byteCount, bool flush)
{
// Validate parameters
if (chars == null || bytes == null)
throw new ArgumentNullException((chars == null ? "chars" : "bytes"),
Environment.GetResourceString("ArgumentNull_Array"));
if (byteCount < 0 || charCount < 0)
throw new ArgumentOutOfRangeException((byteCount<0 ? "byteCount" : "charCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
Contract.EndContractBlock();
this.m_mustFlush = flush;
this.m_throwOnOverflow = true;
return m_encoding.GetBytes(chars, charCount, bytes, byteCount, this);
}
// This method is used when your output buffer might not be large enough for the entire result.
// Just call the pointer version. (This gets bytes)
[System.Security.SecuritySafeCritical] // auto-generated
public override unsafe void Convert(char[] chars, int charIndex, int charCount,
byte[] bytes, int byteIndex, int byteCount, bool flush,
out int charsUsed, out int bytesUsed, out bool completed)
{
// 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 (byteIndex < 0 || byteCount < 0)
throw new ArgumentOutOfRangeException((byteIndex<0 ? "byteIndex" : "byteCount"),
Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum"));
if (chars.Length - charIndex < charCount)
throw new ArgumentOutOfRangeException("chars",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
if (bytes.Length - byteIndex < byteCount)
throw new ArgumentOutOfRangeException("bytes",
Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer"));
Contract.EndContractBlock();
// Avoid empty input problem
if (chars.Length == 0)
chars = new char[1];
if (bytes.Length == 0)
bytes = new byte[1];
// Just call the pointer version (can't do this for non-msft encoders)
fixed (char* pChars = chars)
{
fixed (byte* pBytes = bytes)
{
Convert(pChars + charIndex, charCount, pBytes + byteIndex, byteCount, flush,
out charsUsed, out bytesUsed, out completed);
}
}
}
// This is the version that uses pointers. We call the base encoding worker function
// after setting our appropriate internal variables. This is getting bytes
[System.Security.SecurityCritical] // auto-generated
public override unsafe void Convert(char* chars, int charCount,
byte* bytes, int byteCount, bool flush,
out int charsUsed, out int bytesUsed, out bool completed)
{
// Validate input 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();
// We don't want to throw
this.m_mustFlush = flush;
this.m_throwOnOverflow = false;
this.m_charsUsed = 0;
// Do conversion
bytesUsed = this.m_encoding.GetBytes(chars, charCount, bytes, byteCount, this);
charsUsed = this.m_charsUsed;
// Its completed if they've used what they wanted AND if they didn't want flush or if we are flushed
completed = (charsUsed == charCount) && (!flush || !this.HasState) &&
(m_fallbackBuffer == null || m_fallbackBuffer.Remaining == 0);
// Our data thingys are now full, we can return
}
public Encoding Encoding
{
get
{
return m_encoding;
}
}
public bool MustFlush
{
get
{
return m_mustFlush;
}
}
// Anything left in our encoder?
internal virtual bool HasState
{
get
{
return (this.charLeftOver != (char)0);
}
}
// Allow encoding to clear our must flush instead of throwing (in ThrowBytesOverflow)
internal void ClearMustFlush()
{
m_mustFlush = false;
}
}
}
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