EncodingProvider.cs

using System.Runtime.InteropServices;

namespace System.Text
{
    [ComVisible(true)]
    [__DynamicallyInvokable]
    public abstract class EncodingProvider
    {
        private static object s_InternalSyncObject = new object();

        private static volatile EncodingProvider[] s_providers;

        [__DynamicallyInvokable]
        public EncodingProvider()
        {
        }

        [__DynamicallyInvokable]
        public abstract Encoding GetEncoding(string name);

        [__DynamicallyInvokable]
        public abstract Encoding GetEncoding(int codepage);

        [__DynamicallyInvokable]
        public virtual Encoding GetEncoding(string name, EncoderFallback encoderFallback, DecoderFallback decoderFallback)
        {
            Encoding encoding = GetEncoding(name);
            if (encoding != null)
            {
                encoding = (Encoding)GetEncoding(name).Clone();
                encoding.EncoderFallback = encoderFallback;
                encoding.DecoderFallback = decoderFallback;
            }
            return encoding;
        }

        [__DynamicallyInvokable]
        public virtual Encoding GetEncoding(int codepage, EncoderFallback encoderFallback, DecoderFallback decoderFallback)
        {
            Encoding encoding = GetEncoding(codepage);
            if (encoding != null)
            {
                encoding = (Encoding)GetEncoding(codepage).Clone();
                encoding.EncoderFallback = encoderFallback;
                encoding.DecoderFallback = decoderFallback;
            }
            return encoding;
        }

        internal static void AddProvider(EncodingProvider provider)
        {
            if (provider == null)
            {
                throw new ArgumentNullException("provider");
            }
            lock (s_InternalSyncObject)
            {
                if (s_providers == null)
                {
                    s_providers = new EncodingProvider[1]
                    {
                        provider
                    };
                }
                else if (Array.IndexOf(s_providers, provider) < 0)
                {
                    EncodingProvider[] array = new EncodingProvider[s_providers.Length + 1];
                    Array.Copy(s_providers, array, s_providers.Length);
                    array[array.Length - 1] = provider;
                    s_providers = array;
                }
            }
        }

        internal static Encoding GetEncodingFromProvider(int codepage)
        {
            if (s_providers == null)
            {
                return null;
            }
            EncodingProvider[] array = s_providers;
            EncodingProvider[] array2 = array;
            foreach (EncodingProvider encodingProvider in array2)
            {
                Encoding encoding = encodingProvider.GetEncoding(codepage);
                if (encoding != null)
                {
                    return encoding;
                }
            }
            return null;
        }

        internal static Encoding GetEncodingFromProvider(string encodingName)
        {
            if (s_providers == null)
            {
                return null;
            }
            EncodingProvider[] array = s_providers;
            EncodingProvider[] array2 = array;
            foreach (EncodingProvider encodingProvider in array2)
            {
                Encoding encoding = encodingProvider.GetEncoding(encodingName);
                if (encoding != null)
                {
                    return encoding;
                }
            }
            return null;
        }

        internal static Encoding GetEncodingFromProvider(int codepage, EncoderFallback enc, DecoderFallback dec)
        {
            if (s_providers == null)
            {
                return null;
            }
            EncodingProvider[] array = s_providers;
            EncodingProvider[] array2 = array;
            foreach (EncodingProvider encodingProvider in array2)
            {
                Encoding encoding = encodingProvider.GetEncoding(codepage, enc, dec);
                if (encoding != null)
                {
                    return encoding;
                }
            }
            return null;
        }

        internal static Encoding GetEncodingFromProvider(string encodingName, EncoderFallback enc, DecoderFallback dec)
        {
            if (s_providers == null)
            {
                return null;
            }
            EncodingProvider[] array = s_providers;
            EncodingProvider[] array2 = array;
            foreach (EncodingProvider encodingProvider in array2)
            {
                Encoding encoding = encodingProvider.GetEncoding(encodingName, enc, dec);
                if (encoding != null)
                {
                    return encoding;
                }
            }
            return null;
        }
    }
}