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Diffstat (limited to 'src/mscorlib/src/System/Text/Decoder.cs')
| -rw-r--r-- | src/mscorlib/src/System/Text/Decoder.cs | 338 |
1 files changed, 0 insertions, 338 deletions
diff --git a/src/mscorlib/src/System/Text/Decoder.cs b/src/mscorlib/src/System/Text/Decoder.cs deleted file mode 100644 index a9fea82a39..0000000000 --- a/src/mscorlib/src/System/Text/Decoder.cs +++ /dev/null @@ -1,338 +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. - -namespace System.Text -{ - using System.Runtime.Serialization; - using System.Text; - using System; - using System.Diagnostics; - using System.Diagnostics.Contracts; - // A Decoder is used to decode a sequence of blocks of bytes into a - // sequence of blocks of characters. Following instantiation of a decoder, - // sequential blocks of bytes are converted into blocks of characters through - // calls to the GetChars method. The decoder maintains state between the - // conversions, allowing it to correctly decode byte sequences that span - // adjacent blocks. - // - // Instances of specific implementations of the Decoder abstract base - // class are typically obtained through calls to the GetDecoder method - // of Encoding objects. - // - [Serializable] - public abstract class Decoder - { - internal DecoderFallback m_fallback = null; - - [NonSerialized] - internal DecoderFallbackBuffer m_fallbackBuffer = null; - - internal void SerializeDecoder(SerializationInfo info) - { - info.AddValue("m_fallback", this.m_fallback); - } - - protected Decoder( ) - { - // We don't call default reset because default reset probably isn't good if we aren't initialized. - } - - public DecoderFallback Fallback - { - get - { - return m_fallback; - } - - set - { - if (value == null) - throw new ArgumentNullException(nameof(value)); - Contract.EndContractBlock(); - - // Can't change fallback if buffer is wrong - if (m_fallbackBuffer != null && m_fallbackBuffer.Remaining > 0) - throw new ArgumentException( - Environment.GetResourceString("Argument_FallbackBufferNotEmpty"), nameof(value)); - - m_fallback = value; - m_fallbackBuffer = null; - } - } - - // Note: we don't test for threading here because async access to Encoders and Decoders - // doesn't work anyway. - public DecoderFallbackBuffer FallbackBuffer - { - get - { - if (m_fallbackBuffer == null) - { - if (m_fallback != null) - m_fallbackBuffer = m_fallback.CreateFallbackBuffer(); - else - m_fallbackBuffer = DecoderFallback.ReplacementFallback.CreateFallbackBuffer(); - } - - return m_fallbackBuffer; - } - } - - internal bool InternalHasFallbackBuffer - { - get - { - return m_fallbackBuffer != null; - } - } - - // Reset the Decoder - // - // Normally if we call GetChars() and an error is thrown we don't change the state of the Decoder. This - // would allow the caller to correct the error condition and try again (such as if they need a bigger buffer.) - // - // If the caller doesn't want to try again after GetChars() throws an error, then they need to call Reset(). - // - // Virtual implimentation has to call GetChars with flush and a big enough buffer to clear a 0 byte string - // We avoid GetMaxCharCount() because a) we can't call the base encoder and b) it might be really big. - public virtual void Reset() - { - byte[] byteTemp = Array.Empty<byte>(); - char[] charTemp = new char[GetCharCount(byteTemp, 0, 0, true)]; - GetChars(byteTemp, 0, 0, charTemp, 0, true); - if (m_fallbackBuffer != null) - m_fallbackBuffer.Reset(); - } - - // Returns the number of characters the next call to GetChars will - // produce if presented with the given range of bytes. The returned value - // takes into account the state in which the decoder was left following the - // last call to GetChars. The state of the decoder is not affected - // by a call to this method. - // - public abstract int GetCharCount(byte[] bytes, int index, int count); - - public virtual int GetCharCount(byte[] bytes, int index, int count, bool flush) - { - return GetCharCount(bytes, index, count); - } - - // We expect this to be the workhorse for NLS Encodings, but for existing - // ones we need a working (if slow) default implimentation) - [CLSCompliant(false)] - public virtual unsafe int GetCharCount(byte* bytes, int count, bool flush) - { - // Validate input parameters - if (bytes == null) - throw new ArgumentNullException(nameof(bytes), - Environment.GetResourceString("ArgumentNull_Array")); - - if (count < 0) - throw new ArgumentOutOfRangeException(nameof(count), - Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum")); - Contract.EndContractBlock(); - - byte[] arrbyte = new byte[count]; - int index; - - for (index = 0; index < count; index++) - arrbyte[index] = bytes[index]; - - return GetCharCount(arrbyte, 0, count); - } - - // Decodes a range of bytes in a byte array into a range of characters - // in a character array. The method decodes byteCount bytes from - // bytes starting at index byteIndex, storing the resulting - // characters in chars starting at index charIndex. The - // decoding takes into account the state in which the decoder was left - // following the last call to this method. - // - // An exception occurs if the character array is not large enough to - // hold the complete decoding of the bytes. The GetCharCount method - // can be used to determine the exact number of characters that will be - // produced for a given range of bytes. Alternatively, the - // GetMaxCharCount method of the Encoding that produced this - // decoder can be used to determine the maximum number of characters that - // will be produced for a given number of bytes, regardless of the actual - // byte values. - // - public abstract int GetChars(byte[] bytes, int byteIndex, int byteCount, - char[] chars, int charIndex); - - public virtual int GetChars(byte[] bytes, int byteIndex, int byteCount, - char[] chars, int charIndex, bool flush) - { - return GetChars(bytes, byteIndex, byteCount, chars, charIndex); - } - - // We expect this to be the workhorse for NLS Encodings, but for existing - // ones we need a working (if slow) default implimentation) - // - // WARNING WARNING WARNING - // - // WARNING: If this breaks it could be a security threat. Obviously we - // call this internally, so you need to make sure that your pointers, counts - // and indexes are correct when you call this method. - // - // In addition, we have internal code, which will be marked as "safe" calling - // this code. However this code is dependent upon the implimentation of an - // external GetChars() method, which could be overridden by a third party and - // the results of which cannot be guaranteed. We use that result to copy - // the char[] to our char* output buffer. If the result count was wrong, we - // could easily overflow our output buffer. Therefore we do an extra test - // when we copy the buffer so that we don't overflow charCount either. - [CLSCompliant(false)] - public virtual unsafe int GetChars(byte* bytes, int byteCount, - char* chars, int charCount, bool flush) - { - // Validate input parameters - if (chars == null || bytes == null) - throw new ArgumentNullException(chars == null ? nameof(chars) : nameof(bytes), - Environment.GetResourceString("ArgumentNull_Array")); - - if (byteCount < 0 || charCount < 0) - throw new ArgumentOutOfRangeException((byteCount<0 ? nameof(byteCount) : nameof(charCount)), - Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum")); - Contract.EndContractBlock(); - - // Get the byte array to convert - byte[] arrByte = new byte[byteCount]; - - int index; - for (index = 0; index < byteCount; index++) - arrByte[index] = bytes[index]; - - // Get the char array to fill - char[] arrChar = new char[charCount]; - - // Do the work - int result = GetChars(arrByte, 0, byteCount, arrChar, 0, flush); - - Debug.Assert(result <= charCount, "Returned more chars than we have space for"); - - // Copy the char array - // WARNING: We MUST make sure that we don't copy too many chars. We can't - // rely on result because it could be a 3rd party implimentation. We need - // to make sure we never copy more than charCount chars no matter the value - // of result - if (result < charCount) - charCount = result; - - // We check both result and charCount so that we don't accidentally overrun - // our pointer buffer just because of an issue in GetChars - for (index = 0; index < charCount; index++) - chars[index] = arrChar[index]; - - return charCount; - } - - // This method is used when the output buffer might not be large enough. - // It will decode until it runs out of bytes, and then it will return - // true if it the entire input was converted. In either case it - // will also return the number of converted bytes and output characters used. - // It will only throw a buffer overflow exception if the entire lenght of chars[] is - // too small to store the next char. (like 0 or maybe 1 or 4 for some encodings) - // We're done processing this buffer only if completed returns true. - // - // Might consider checking Max...Count to avoid the extra counting step. - // - // Note that if all of the input bytes are not consumed, then we'll do a /2, which means - // that its likely that we didn't consume as many bytes as we could have. For some - // applications this could be slow. (Like trying to exactly fill an output buffer from a bigger stream) - public virtual void Convert(byte[] bytes, int byteIndex, int byteCount, - char[] chars, int charIndex, int charCount, bool flush, - out int bytesUsed, out int charsUsed, out bool completed) - { - // Validate parameters - if (bytes == null || chars == null) - throw new ArgumentNullException((bytes == null ? nameof(bytes) : nameof(chars)), - Environment.GetResourceString("ArgumentNull_Array")); - - if (byteIndex < 0 || byteCount < 0) - throw new ArgumentOutOfRangeException((byteIndex<0 ? nameof(byteIndex) : nameof(byteCount)), - Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum")); - - if (charIndex < 0 || charCount < 0) - throw new ArgumentOutOfRangeException((charIndex<0 ? nameof(charIndex) : nameof(charCount)), - Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum")); - - if (bytes.Length - byteIndex < byteCount) - throw new ArgumentOutOfRangeException(nameof(bytes), - Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer")); - - if (chars.Length - charIndex < charCount) - throw new ArgumentOutOfRangeException(nameof(chars), - Environment.GetResourceString("ArgumentOutOfRange_IndexCountBuffer")); - Contract.EndContractBlock(); - - bytesUsed = byteCount; - - // Its easy to do if it won't overrun our buffer. - while (bytesUsed > 0) - { - if (GetCharCount(bytes, byteIndex, bytesUsed, flush) <= charCount) - { - charsUsed = GetChars(bytes, byteIndex, bytesUsed, chars, charIndex, flush); - completed = (bytesUsed == byteCount && - (m_fallbackBuffer == null || m_fallbackBuffer.Remaining == 0)); - return; - } - - // Try again with 1/2 the count, won't flush then 'cause won't read it all - flush = false; - bytesUsed /= 2; - } - - // Oops, we didn't have anything, we'll have to throw an overflow - throw new ArgumentException(Environment.GetResourceString("Argument_ConversionOverflow")); - } - - // This is the version that uses *. - // We're done processing this buffer only if completed returns true. - // - // Might consider checking Max...Count to avoid the extra counting step. - // - // Note that if all of the input bytes are not consumed, then we'll do a /2, which means - // that its likely that we didn't consume as many bytes as we could have. For some - // applications this could be slow. (Like trying to exactly fill an output buffer from a bigger stream) - [CLSCompliant(false)] - public virtual unsafe void Convert(byte* bytes, int byteCount, - char* chars, int charCount, bool flush, - out int bytesUsed, out int charsUsed, out bool completed) - { - // Validate input parameters - if (chars == null || bytes == null) - throw new ArgumentNullException(chars == null ? nameof(chars) : nameof(bytes), - Environment.GetResourceString("ArgumentNull_Array")); - - if (byteCount < 0 || charCount < 0) - throw new ArgumentOutOfRangeException((byteCount<0 ? nameof(byteCount) : nameof(charCount)), - Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegNum")); - Contract.EndContractBlock(); - - // Get ready to do it - bytesUsed = byteCount; - - // Its easy to do if it won't overrun our buffer. - while (bytesUsed > 0) - { - if (GetCharCount(bytes, bytesUsed, flush) <= charCount) - { - charsUsed = GetChars(bytes, bytesUsed, chars, charCount, flush); - completed = (bytesUsed == byteCount && - (m_fallbackBuffer == null || m_fallbackBuffer.Remaining == 0)); - return; - } - - // Try again with 1/2 the count, won't flush then 'cause won't read it all - flush = false; - bytesUsed /= 2; - } - - // Oops, we didn't have anything, we'll have to throw an overflow - throw new ArgumentException(Environment.GetResourceString("Argument_ConversionOverflow")); - } - } -} |