708 lines
28 KiB
C#
708 lines
28 KiB
C#
using System;
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using Unity.Collections.LowLevel.Unsafe;
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namespace Unity.Collections
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{
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/// <summary>
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/// Kinds of format errors.
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/// </summary>
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public enum FormatError
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{
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/// <summary>
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/// No error.
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/// </summary>
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None,
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/// <summary>
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/// The target storage does not have sufficient capacity.
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/// Note that the format's write failed. It did not truncate.
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/// </summary>
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Overflow,
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/// <summary>
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/// The source format specifier is not itself correctly formatted, or
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/// a format specifier tokens were found outside of accepted usage.
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/// Note that the format's write failed.
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/// </summary>
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BadFormatSpecifier,
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}
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/// <summary>
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/// Kinds of parse errors.
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/// </summary>
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public enum ParseError
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{
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/// <summary>
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/// No parse error.
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/// </summary>
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None,
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/// <summary>
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/// The text parsed does not form a number.
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/// </summary>
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Syntax,
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/// <summary>
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/// The number exceeds the range of the target type.
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/// The number was either truncated, or failed to write entirely.
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/// </summary>
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Overflow,
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/// <summary>
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/// The number exceeds the precision of the target type.
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/// </summary>
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Underflow,
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}
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/// <summary>
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/// Kinds of copy errors.
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/// </summary>
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public enum CopyError
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{
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/// <summary>
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/// No copy error.
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/// </summary>
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None,
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/// <summary>
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/// The target storage does not have sufficient capacity.
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/// Unless stated in the API comment, assume that the write operation was partially applied.
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/// </summary>
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Truncation,
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}
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/// <summary>
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/// Kinds of conversion errors.
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/// </summary>
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public enum ConversionError
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{
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/// <summary>
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/// No conversion error.
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/// </summary>
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None,
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/// <summary>
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/// The target storage does not have sufficient capacity.
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/// For copy operations; the value was either truncated into the target storage, or failed to write entirely.
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/// </summary>
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Overflow,
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/// <summary>
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/// The bytes do not form a valid character.
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/// </summary>
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Encoding,
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/// <summary>
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/// The rune is not a valid code point.
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/// </summary>
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CodePoint,
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}
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/// <summary>
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/// Provides utility methods for UTF-8, UTF-16, UCS-4 (a.k.a. UTF-32), and WTF-8.
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/// </summary>
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[GenerateTestsForBurstCompatibility]
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public unsafe struct Unicode
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{
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/// <summary>
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/// Representation of a Unicode character as a code point.
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/// </summary>
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[GenerateTestsForBurstCompatibility]
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public struct Rune
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{
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/// <summary>
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/// The code point.
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/// </summary>
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/// <value>The code point.</value>
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public int value;
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/// <summary>
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/// Initializes and returns an instance of Rune.
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/// </summary>
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/// <remarks>You are responsible for the code point being valid.</remarks>
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/// <param name="codepoint">The code point.</param>
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public Rune(int codepoint)
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{
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value = codepoint;
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}
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/// <summary>
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/// Returns a rune.
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/// </summary>
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/// <remarks>Because a char is 16-bit, it can only represent the first 2^16 code points, not all 1.1 million.</remarks>
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/// <param name="codepoint">A code point.</param>
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/// <returns>A rune.</returns>
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public static implicit operator Rune(char codepoint) => new Rune { value = codepoint };
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/// <summary>
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/// Evaluates if one is equal to the other.
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/// </summary>
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/// <param name="lhs">The left-hand side</param>
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/// <param name="rhs">The right-hand side</param>
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/// <returns>True if the left-hand side's is equal to the right-hand side's.</returns>
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public static bool operator ==(Rune lhs, Rune rhs)
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{
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return lhs.value == rhs.value;
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}
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/// <summary>
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/// Returns true if the value stored in this Rune is equal to an object.
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/// </summary>
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/// <remarks>Can only be equal if the object is itself a Rune.</remarks>
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/// <param name="obj">An object to compare with.</param>
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/// <returns>True if the value stored in this Rune is equal to the object.</returns>
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[ExcludeFromBurstCompatTesting("Takes managed object")]
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public override bool Equals(object obj)
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{
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if (obj is Rune)
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{
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return value == ((Rune)obj).value;
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}
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return false;
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}
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/// <summary>
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/// A hash used for comparisons.
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/// </summary>
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/// <returns>A unique hash code.</returns>
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public override int GetHashCode()
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{
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return value;
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}
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/// <summary>
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/// Evaluates if one is not equal to the other.
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/// </summary>
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/// <param name="lhs">The left-hand side</param>
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/// <param name="rhs">The right-hand side</param>
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/// <returns>True if the left-hand side's is not equal to the right-hand side's.</returns>
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public static bool operator !=(Rune lhs, Rune rhs)
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{
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return lhs.value != rhs.value;
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}
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/// <summary>
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/// Returns true if a rune is a numerical digit character.
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/// </summary>
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/// <param name="r">The rune.</param>
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/// <returns>True if the rune is a numerical digit character.</returns>
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public static bool IsDigit(Rune r)
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{
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return r.IsDigit();
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}
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internal bool IsAscii()
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{
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return value < 0x80;
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}
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internal bool IsLatin1()
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{
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return value < 0x100;
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}
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internal bool IsDigit()
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{
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return value >= '0' && value <= '9';
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}
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internal bool IsWhiteSpace()
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{
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// https://en.wikipedia.org/wiki/Whitespace_character#Unicode
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if (IsLatin1())
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{
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return value == ' '
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|| (value >= 0x9 && value <= 0xD) // CHARACTER TABULATION (U+0009), LINE FEED (U+000A), LINE TABULATION (U+000B), FORM FEED (U+000C), CARRIAGE RETURN (U+000D)
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|| value == 0xA0 // NO-BREAK SPACE
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|| value == 0x85 // NEXT LINE
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;
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}
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return value == 0x1680 // OGHAM SPACE MARK
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|| (value >= 0x2000 && value <= 0x200A) // EN QUAD(U+2000)
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// EM QUAD(U+2001)
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// EN SPACE(U+2002)
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// EM SPACE(U+2003)
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// THREE - PER - EM SPACE(U + 2004)
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// FOUR - PER - EM SPACE(U + 2005)
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// SIX - PER - EM SPACE(U + 2006)
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// FIGURE SPACE(U+2007)
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// PUNCTUATION SPACE(U+2008)
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// THIN SPACE(U+2009)
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// HAIR SPACE(U+200A)
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|| value == 0x2028 // LINE SEPARATOR
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|| value == 0x2029 // PARAGRAPH SEPARATOR
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|| value == 0x202F // NARROW NO-BREAK SPACE
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|| value == 0x205F // MEDIUM MATHEMATICAL SPACE
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|| value == 0x3000 // IDEOGRAPHIC SPACE
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;
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}
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internal Rune ToLowerAscii()
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{
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return new Rune(value + (((uint)(value - 'A') <= ('Z' - 'A')) ? 0x20 : 0));
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}
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internal Rune ToUpperAscii()
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{
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return new Rune(value - (((uint)(value - 'a') <= ('z' - 'a')) ? 0x20 : 0));
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}
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/// <summary>
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/// Returns the number of bytes required to encode this rune as UTF-8.
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/// </summary>
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/// <returns>The number of bytes required to encode this rune as UTF-8. If the rune's codepoint
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/// is invalid, returns 4 (the maximum possible encoding length).</returns>
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public int LengthInUtf8Bytes()
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{
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if (value < 0)
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return 4; // invalid codepoint
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if (value <= 0x7F)
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return 1;
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if (value <= 0x7FF)
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return 2;
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if (value <= 0xFFFF)
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return 3;
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if (value <= 0x1FFFFF)
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return 4;
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// invalid codepoint, max size.
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return 4;
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}
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}
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/// <summary>The maximum value of a valid UNICODE code point</summary>
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public const int kMaximumValidCodePoint = 0x10FFFF;
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/// <summary>
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/// Returns true if a code point is valid.
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/// </summary>
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/// <param name="codepoint">A code point.</param>
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/// <returns>True if a code point is valid.</returns>
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public static bool IsValidCodePoint(int codepoint)
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{
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if (codepoint > kMaximumValidCodePoint) // maximum valid code point
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return false;
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// if (codepoint >= 0xD800 && codepoint <= 0xDFFF) // surrogate pair
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// return false;
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if (codepoint < 0) // negative?
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return false;
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return true;
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}
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/// <summary>
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/// Returns true if the byte is not the last byte of a UTF-8 character.
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/// </summary>
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/// <param name="b">The byte.</param>
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/// <returns>True if the byte is not the last byte of a UTF-8 character.</returns>
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public static bool NotTrailer(byte b)
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{
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return (b & 0xC0) != 0x80;
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}
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/// <summary>
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/// The Unicode character <20>.
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/// </summary>
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/// <remarks>This character is used to stand-in for characters that can't be rendered.</remarks>
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/// <value>The Unicode character <20>.</value>
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public static Rune ReplacementCharacter => new Rune { value = 0xFFFD };
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/// <summary>
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/// The null rune value.
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/// </summary>
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/// <remarks>In this package, the "bad rune" is used as a null character. It represents no valid code point.</remarks>
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/// <value>The null rune value.</value>
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public static Rune BadRune => new Rune { value = 0 };
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/// <summary>
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/// Reads a UTF-8 encoded character from a buffer.
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/// </summary>
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/// <param name="rune">Outputs the character read. If the read fails, outputs <see cref="ReplacementCharacter"/>.</param>
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/// <param name="buffer">The buffer of bytes to read.</param>
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/// <param name="index">Reference to a byte index into the buffer. If the read succeeds, index is incremented by the
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/// size in bytes of the character read. If the read fails, index is incremented by 1.</param>
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/// <param name="capacity">The size in bytes of the buffer. Used to check that the read is in bounds.</param>
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/// <returns><see cref="ConversionError.None"/> if the read succeeds. Otherwise, returns <see cref="ConversionError.Overflow"/> or <see cref="ConversionError.Encoding"/>.</returns>
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public static ConversionError Utf8ToUcs(out Rune rune, byte* buffer, ref int index, int capacity)
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{
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int code = 0;
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rune = ReplacementCharacter;
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if (index + 1 > capacity)
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{
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return ConversionError.Overflow;
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}
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if ((buffer[index] & 0b10000000) == 0b00000000) // if high bit is 0, 1 byte
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{
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rune.value = buffer[index + 0];
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index += 1;
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return ConversionError.None;
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}
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if ((buffer[index] & 0b11100000) == 0b11000000) // if high 3 bits are 110, 2 bytes
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{
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if (index + 2 > capacity)
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{
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index += 1;
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return ConversionError.Overflow;
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}
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code = (buffer[index + 0] & 0b00011111);
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code = (code << 6) | (buffer[index + 1] & 0b00111111);
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if (code < (1 << 7) || NotTrailer(buffer[index + 1]))
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{
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index += 1;
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return ConversionError.Encoding;
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}
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rune.value = code;
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index += 2;
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return ConversionError.None;
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}
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if ((buffer[index] & 0b11110000) == 0b11100000) // if high 4 bits are 1110, 3 bytes
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{
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if (index + 3 > capacity)
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{
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index += 1;
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return ConversionError.Overflow;
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}
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code = (buffer[index + 0] & 0b00001111);
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code = (code << 6) | (buffer[index + 1] & 0b00111111);
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code = (code << 6) | (buffer[index + 2] & 0b00111111);
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if (code < (1 << 11) || !IsValidCodePoint(code) || NotTrailer(buffer[index + 1]) || NotTrailer(buffer[index + 2]))
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{
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index += 1;
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return ConversionError.Encoding;
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}
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rune.value = code;
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index += 3;
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return ConversionError.None;
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}
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if ((buffer[index] & 0b11111000) == 0b11110000) // if high 5 bits are 11110, 4 bytes
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{
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if (index + 4 > capacity)
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{
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index += 1;
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return ConversionError.Overflow;
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}
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code = (buffer[index + 0] & 0b00000111);
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code = (code << 6) | (buffer[index + 1] & 0b00111111);
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code = (code << 6) | (buffer[index + 2] & 0b00111111);
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code = (code << 6) | (buffer[index + 3] & 0b00111111);
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if (code < (1 << 16) || !IsValidCodePoint(code) || NotTrailer(buffer[index + 1]) || NotTrailer(buffer[index + 2]) || NotTrailer(buffer[index + 3]))
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{
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index += 1;
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return ConversionError.Encoding;
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}
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rune.value = code;
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index += 4;
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return ConversionError.None;
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}
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index += 1;
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return ConversionError.Encoding;
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}
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static int FindUtf8CharStartInReverse(byte* ptr, ref int index)
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{
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do
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{
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if (index <= 0)
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{
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return 0;
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}
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--index;
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} while ((ptr[index] & 0xC0) == 0x80);
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return index;
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}
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internal static ConversionError Utf8ToUcsReverse(out Rune rune, byte* buffer, ref int index, int capacity)
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{
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var prev = index;
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--index;
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index = FindUtf8CharStartInReverse(buffer, ref index);
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if (index == prev)
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{
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rune = ReplacementCharacter;
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return ConversionError.Overflow;
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}
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var ignore = index;
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return Utf8ToUcs(out rune, buffer, ref ignore, capacity);
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}
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/// <summary>
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/// Returns true if a char is a Unicode leading surrogate.
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/// </summary>
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/// <param name="c">The char.</param>
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/// <returns>True if the char is a Unicode leading surrogate.</returns>
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static bool IsLeadingSurrogate(char c)
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{
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return c >= 0xD800 && c <= 0xDBFF;
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}
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/// <summary>
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/// Returns true if a char is a Unicode trailing surrogate.
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/// </summary>
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/// <param name="c">The char.</param>
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/// <returns>True if the char is a Unicode trailing surrogate.</returns>
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static bool IsTrailingSurrogate(char c)
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{
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return c >= 0xDC00 && c <= 0xDFFF;
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}
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/// <summary>
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/// Reads a UTF-16 encoded character from a buffer.
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/// </summary>
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/// <param name="rune">Outputs the character read. If the read fails, rune is not set.</param>
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/// <param name="buffer">The buffer of chars to read.</param>
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/// <param name="index">Reference to a char index into the buffer. If the read succeeds, index is incremented by the
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/// size in chars of the character read. If the read fails, index is not incremented.</param>
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/// <param name="capacity">The size in chars of the buffer. Used to check that the read is in bounds.</param>
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/// <returns><see cref="ConversionError.None"/> if the read succeeds. Otherwise, returns <see cref="ConversionError.Overflow"/>.</returns>
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public static ConversionError Utf16ToUcs(out Rune rune, char* buffer, ref int index, int capacity)
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{
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int code = 0;
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rune = ReplacementCharacter;
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if (index + 1 > capacity)
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return ConversionError.Overflow;
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if (!IsLeadingSurrogate(buffer[index]) || (index + 2 > capacity))
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{
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rune.value = buffer[index];
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index += 1;
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return ConversionError.None;
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}
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code = (buffer[index + 0] & 0x03FF);
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char next = buffer[index + 1];
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if (!IsTrailingSurrogate(next))
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{
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rune.value = buffer[index];
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index += 1;
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return ConversionError.None;
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}
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code = (code << 10) | (buffer[index + 1] & 0x03FF);
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code += 0x10000;
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rune.value = code;
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index += 2;
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return ConversionError.None;
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}
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internal static ConversionError UcsToUcs(out Rune rune, Rune* buffer, ref int index, int capacity)
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{
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rune = ReplacementCharacter;
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if (index + 1 > capacity)
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return ConversionError.Overflow;
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rune = buffer[index];
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index += 1;
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return ConversionError.None;
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}
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/// <summary>
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/// Writes a rune to a buffer as a UTF-8 encoded character.
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/// </summary>
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/// <param name="rune">The rune to encode.</param>
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/// <param name="buffer">The buffer to write to.</param>
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/// <param name="index">Reference to a byte index into the buffer. If the write succeeds, index is incremented by the
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/// size in bytes of the character written. If the write fails, index is not incremented.</param>
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/// <param name="capacity">The size in bytes of the buffer. Used to check that the write is in bounds.</param>
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/// <returns><see cref="ConversionError.None"/> if the write succeeds. Otherwise, returns <see cref="ConversionError.CodePoint"/>, <see cref="ConversionError.Overflow"/>, or <see cref="ConversionError.Encoding"/>.</returns>
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public static ConversionError UcsToUtf8(byte* buffer, ref int index, int capacity, Rune rune)
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{
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if (!IsValidCodePoint(rune.value))
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{
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return ConversionError.CodePoint;
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}
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if (index + 1 > capacity)
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{
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return ConversionError.Overflow;
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}
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|
||
if (rune.value <= 0x7F)
|
||
{
|
||
buffer[index++] = (byte)rune.value;
|
||
return ConversionError.None;
|
||
}
|
||
|
||
if (rune.value <= 0x7FF)
|
||
{
|
||
if (index + 2 > capacity)
|
||
{
|
||
return ConversionError.Overflow;
|
||
}
|
||
|
||
buffer[index++] = (byte)(0xC0 | (rune.value >> 6));
|
||
buffer[index++] = (byte)(0x80 | ((rune.value >> 0) & 0x3F));
|
||
return ConversionError.None;
|
||
}
|
||
|
||
if (rune.value <= 0xFFFF)
|
||
{
|
||
if (index + 3 > capacity)
|
||
{
|
||
return ConversionError.Overflow;
|
||
}
|
||
|
||
buffer[index++] = (byte)(0xE0 | (rune.value >> 12));
|
||
buffer[index++] = (byte)(0x80 | ((rune.value >> 6) & 0x3F));
|
||
buffer[index++] = (byte)(0x80 | ((rune.value >> 0) & 0x3F));
|
||
return ConversionError.None;
|
||
}
|
||
|
||
if (rune.value <= 0x1FFFFF)
|
||
{
|
||
if (index + 4 > capacity)
|
||
{
|
||
return ConversionError.Overflow;
|
||
}
|
||
|
||
buffer[index++] = (byte)(0xF0 | (rune.value >> 18));
|
||
buffer[index++] = (byte)(0x80 | ((rune.value >> 12) & 0x3F));
|
||
buffer[index++] = (byte)(0x80 | ((rune.value >> 6) & 0x3F));
|
||
buffer[index++] = (byte)(0x80 | ((rune.value >> 0) & 0x3F));
|
||
return ConversionError.None;
|
||
}
|
||
|
||
return ConversionError.Encoding;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Writes a rune to a buffer as a UTF-16 encoded character.
|
||
/// </summary>
|
||
/// <param name="rune">The rune to encode.</param>
|
||
/// <param name="buffer">The buffer of chars to write to.</param>
|
||
/// <param name="index">Reference to a char index into the buffer. If the write succeeds, index is incremented by the
|
||
/// size in chars of the character written. If the write fails, index is not incremented.</param>
|
||
/// <param name="capacity">The size in chars of the buffer. Used to check that the write is in bounds.</param>
|
||
/// <returns><see cref="ConversionError.None"/> if the write succeeds. Otherwise, returns <see cref="ConversionError.CodePoint"/>, <see cref="ConversionError.Overflow"/>, or <see cref="ConversionError.Encoding"/>.</returns>
|
||
public static ConversionError UcsToUtf16(char* buffer, ref int index, int capacity, Rune rune)
|
||
{
|
||
if (!IsValidCodePoint(rune.value))
|
||
{
|
||
return ConversionError.CodePoint;
|
||
}
|
||
|
||
if (index + 1 > capacity)
|
||
{
|
||
return ConversionError.Overflow;
|
||
}
|
||
|
||
if (rune.value >= 0x10000)
|
||
{
|
||
if (index + 2 > capacity)
|
||
{
|
||
return ConversionError.Overflow;
|
||
}
|
||
|
||
int code = rune.value - 0x10000;
|
||
if (code >= (1 << 20))
|
||
{
|
||
return ConversionError.Encoding;
|
||
}
|
||
|
||
buffer[index++] = (char)(0xD800 | (code >> 10));
|
||
buffer[index++] = (char)(0xDC00 | (code & 0x3FF));
|
||
return ConversionError.None;
|
||
}
|
||
|
||
buffer[index++] = (char)rune.value;
|
||
return ConversionError.None;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Copies UTF-16 characters from one buffer to another buffer as UTF-8.
|
||
/// </summary>
|
||
/// <remarks>Assumes the source data is valid UTF-16.</remarks>
|
||
/// <param name="utf16Buffer">The source buffer.</param>
|
||
/// <param name="utf16Length">The number of chars to read from the source.</param>
|
||
/// <param name="utf8Buffer">The destination buffer.</param>
|
||
/// <param name="utf8Length">Outputs the number of bytes written to the destination.</param>
|
||
/// <param name="utf8Capacity">The size in bytes of the destination buffer.</param>
|
||
/// <returns><see cref="ConversionError.None"/> if the copy fully completes. Otherwise, returns <see cref="ConversionError.Overflow"/>.</returns>
|
||
public static ConversionError Utf16ToUtf8(char* utf16Buffer, int utf16Length, byte* utf8Buffer, out int utf8Length, int utf8Capacity)
|
||
{
|
||
utf8Length = 0;
|
||
for (var utf16Offset = 0; utf16Offset < utf16Length;)
|
||
{
|
||
Utf16ToUcs(out var ucs, utf16Buffer, ref utf16Offset, utf16Length);
|
||
if (UcsToUtf8(utf8Buffer, ref utf8Length, utf8Capacity, ucs) == ConversionError.Overflow)
|
||
return ConversionError.Overflow;
|
||
}
|
||
return ConversionError.None;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Copies UTF-8 characters from one buffer to another.
|
||
/// </summary>
|
||
/// <remarks>Assumes the source data is valid UTF-8.</remarks>
|
||
/// <param name="srcBuffer">The source buffer.</param>
|
||
/// <param name="srcLength">The number of bytes to read from the source.</param>
|
||
/// <param name="destBuffer">The destination buffer.</param>
|
||
/// <param name="destLength">Outputs the number of bytes written to the destination.</param>
|
||
/// <param name="destCapacity">The size in bytes of the destination buffer.</param>
|
||
/// <returns><see cref="ConversionError.None"/> if the copy fully completes. Otherwise, returns <see cref="ConversionError.Overflow"/>.</returns>
|
||
public static ConversionError Utf8ToUtf8(byte* srcBuffer, int srcLength, byte* destBuffer, out int destLength, int destCapacity)
|
||
{
|
||
if (destCapacity >= srcLength)
|
||
{
|
||
UnsafeUtility.MemCpy(destBuffer, srcBuffer, srcLength);
|
||
destLength = srcLength;
|
||
return ConversionError.None;
|
||
}
|
||
// TODO even in this case, it's possible to MemCpy all but the last 3 bytes that fit, and then by looking at only
|
||
// TODO the high bits of the last 3 bytes that fit, decide how many of the 3 to append. but that requires a
|
||
// TODO little UNICODE presence of mind that nobody has today.
|
||
destLength = 0;
|
||
for (var srcOffset = 0; srcOffset < srcLength;)
|
||
{
|
||
Utf8ToUcs(out var ucs, srcBuffer, ref srcOffset, srcLength);
|
||
if (UcsToUtf8(destBuffer, ref destLength, destCapacity, ucs) == ConversionError.Overflow)
|
||
return ConversionError.Overflow;
|
||
}
|
||
return ConversionError.None;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Copies UTF-8 characters from one buffer to another as UTF-16.
|
||
/// </summary>
|
||
/// <remarks>Assumes the source data is valid UTF-8.</remarks>
|
||
/// <param name="utf8Buffer">The source buffer.</param>
|
||
/// <param name="utf8Length">The number of bytes to read from the source.</param>
|
||
/// <param name="utf16Buffer">The destination buffer.</param>
|
||
/// <param name="utf16Length">Outputs the number of chars written to the destination.</param>
|
||
/// <param name="utf16Capacity">The size in chars of the destination buffer.</param>
|
||
/// <returns><see cref="ConversionError.None"/> if the copy fully completes. Otherwise, <see cref="ConversionError.Overflow"/>.</returns>
|
||
public static ConversionError Utf8ToUtf16(byte* utf8Buffer, int utf8Length, char* utf16Buffer, out int utf16Length, int utf16Capacity)
|
||
{
|
||
utf16Length = 0;
|
||
for (var utf8Offset
|
||
= 0; utf8Offset < utf8Length;)
|
||
{
|
||
Utf8ToUcs(out var ucs, utf8Buffer, ref utf8Offset, utf8Length);
|
||
if (UcsToUtf16(utf16Buffer, ref utf16Length, utf16Capacity, ucs) == ConversionError.Overflow)
|
||
return ConversionError.Overflow;
|
||
}
|
||
return ConversionError.None;
|
||
}
|
||
|
||
static int CountRunes(byte* utf8Buffer, int utf8Length, int maxRunes = int.MaxValue)
|
||
{
|
||
var numRunes = 0;
|
||
|
||
for (var i = 0; numRunes < maxRunes && i < utf8Length; ++i)
|
||
{
|
||
if ((utf8Buffer[i] & 0xC0) != 0x80)
|
||
numRunes++;
|
||
}
|
||
|
||
return numRunes;
|
||
}
|
||
}
|
||
}
|