NameTable.cs

namespace System.Xml
{
    [global::__DynamicallyInvokable]
    public class NameTable : XmlNameTable
    {
        private class Entry
        {
            internal string str;

            internal int hashCode;

            internal Entry next;

            internal Entry(string str, int hashCode, Entry next)
            {
                this.str = str;
                this.hashCode = hashCode;
                this.next = next;
            }
        }

        private Entry[] entries;

        private int count;

        private int mask;

        private int hashCodeRandomizer;

        [global::__DynamicallyInvokable]
        public NameTable()
        {
            mask = 31;
            entries = new Entry[mask + 1];
            hashCodeRandomizer = Environment.TickCount;
        }

        [global::__DynamicallyInvokable]
        public override string Add(string key)
        {
            if (key == null)
            {
                throw new ArgumentNullException("key");
            }
            int length = key.Length;
            if (length == 0)
            {
                return string.Empty;
            }
            int num = length + hashCodeRandomizer;
            for (int i = 0; i < key.Length; i++)
            {
                num += ((num << 7) ^ key[i]);
            }
            num -= num >> 17;
            num -= num >> 11;
            num -= num >> 5;
            for (Entry entry = entries[num & mask]; entry != null; entry = entry.next)
            {
                if (entry.hashCode == num && entry.str.Equals(key))
                {
                    return entry.str;
                }
            }
            return AddEntry(key, num);
        }

        [global::__DynamicallyInvokable]
        public override string Add(char[] key, int start, int len)
        {
            if (len == 0)
            {
                return string.Empty;
            }
            int num = len + hashCodeRandomizer;
            num += ((num << 7) ^ key[start]);
            int num2 = start + len;
            for (int i = start + 1; i < num2; i++)
            {
                num += ((num << 7) ^ key[i]);
            }
            num -= num >> 17;
            num -= num >> 11;
            num -= num >> 5;
            for (Entry entry = entries[num & mask]; entry != null; entry = entry.next)
            {
                if (entry.hashCode == num && TextEquals(entry.str, key, start, len))
                {
                    return entry.str;
                }
            }
            return AddEntry(new string(key, start, len), num);
        }

        [global::__DynamicallyInvokable]
        public override string Get(string value)
        {
            if (value == null)
            {
                throw new ArgumentNullException("value");
            }
            if (value.Length == 0)
            {
                return string.Empty;
            }
            int num = value.Length + hashCodeRandomizer;
            int num2 = num;
            for (int i = 0; i < value.Length; i++)
            {
                num2 += ((num2 << 7) ^ value[i]);
            }
            num2 -= num2 >> 17;
            num2 -= num2 >> 11;
            num2 -= num2 >> 5;
            for (Entry entry = entries[num2 & mask]; entry != null; entry = entry.next)
            {
                if (entry.hashCode == num2 && entry.str.Equals(value))
                {
                    return entry.str;
                }
            }
            return null;
        }

        [global::__DynamicallyInvokable]
        public override string Get(char[] key, int start, int len)
        {
            if (len == 0)
            {
                return string.Empty;
            }
            int num = len + hashCodeRandomizer;
            num += ((num << 7) ^ key[start]);
            int num2 = start + len;
            for (int i = start + 1; i < num2; i++)
            {
                num += ((num << 7) ^ key[i]);
            }
            num -= num >> 17;
            num -= num >> 11;
            num -= num >> 5;
            for (Entry entry = entries[num & mask]; entry != null; entry = entry.next)
            {
                if (entry.hashCode == num && TextEquals(entry.str, key, start, len))
                {
                    return entry.str;
                }
            }
            return null;
        }

        private string AddEntry(string str, int hashCode)
        {
            int num = hashCode & mask;
            Entry entry = new Entry(str, hashCode, entries[num]);
            entries[num] = entry;
            if (count++ == mask)
            {
                Grow();
            }
            return entry.str;
        }

        private void Grow()
        {
            int num = mask * 2 + 1;
            Entry[] array = entries;
            Entry[] array2 = new Entry[num + 1];
            for (int i = 0; i < array.Length; i++)
            {
                Entry next;
                for (Entry entry = array[i]; entry != null; entry = next)
                {
                    int num2 = entry.hashCode & num;
                    next = entry.next;
                    entry.next = array2[num2];
                    array2[num2] = entry;
                }
            }
            entries = array2;
            mask = num;
        }

        private static bool TextEquals(string str1, char[] str2, int str2Start, int str2Length)
        {
            if (str1.Length != str2Length)
            {
                return false;
            }
            for (int i = 0; i < str1.Length; i++)
            {
                if (str1[i] != str2[str2Start + i])
                {
                    return false;
                }
            }
            return true;
        }
    }
}