Add Mac OS encodings

[joachimmetz]

Add Mac OS encodings

Defined by Unicode.org - http://www.unicode.org/Public/MAPPINGS/VENDORS/APPLE/

• MacArabic
  • Digits 0x30 - 0x39 are currently not adjusted for use in Arabic-script context
• MacCeltic
• MacCentralEurRoman
• MacChineseSimp (MBC encoding)
• MacChineseTrad (MBC encoding)
• MacCroatian
• MacCyrillic (MacOS >= 9.0)
• MacDevanagari (MBC encoding)
• MacDingbats
• MacFarsi
  • Digits 0x30 - 0x39 are currently not adjusted for use in Arabic-script context
• MacGaelic
• MacGreek
• MacGujarati (MBC encoding)
• MacGurmukhi (MBC encoding)
• MacHebrew (+/-)
  • Unicode characters for private usage currently not supported
  • 0x81 maps to U+05F2, U+05B7 though Unicode defines U+FB1F
  • 0xde maps to U+05C7, HEBREW.TXT indicates 0x05B8+0xF87F but also hints at alternate form "qamats qatan"
• MacIcelandic
• MacInuit
• MacJapanese (MBC encoding)
• MacKorean (MBC encoding)
• MacRoman (MacOS >= 8.5)
• MacRomanian
• MacRussian (MacCyrillicCurrSignStdVariant) - superseded by MacCyrillic (MacOS >= 9.0)
• MacSymbol (+/-)
  • Unicode characters for private usage currently not supported
• MacThai (+/-)
  • Unicode characters for private usage currently not supported
• MacTurkish
• MacUkrainian (MacCyrillicCurrSignUkrVariant) - superseded by MacCyrillic (MacOS >= 9.0)

Notes:

• <LR> <CHAR> is encoded as U+202d <CHAR> U+202c
• <RL> <CHAR> is encoded as U+202e <CHAR> U+202c
• MacOS seems to use Unicode characters for private usage to tag different "variants" of the same character

TODO: unknown, not defined by Unicode.org, also no mapping data generated by https://github.com/dfirlabs/macos-measurements/blob/main/maccodepage.sh

• MacArmenian
• MacBengali
• MacBurmese
• MacEthiopic
• MacExtArabic
• MacGeorgian
• MacKannada
• MacKhmer
• MacLaotian
• MacMalayalam
• MacMongolian
• MacOriya
• MacSinhalese
• MacTamil
• MacTelugu
• MacTibetan
• MacVietnamese

Notes:

• MacOS does not seem to encode stand-alone versions of Unicode characters into the unknown encodings

TODO, consider adding support for:

• Before Mac OS 8.5, the codepage character 0xDB was mapped to Unicode character U+00A4 (currency sign).

Keeping notes here: https://forensicswiki.xyz/wiki/index.php?title=Mac_OS_X#Codepages