Class: PDF::Reader::EncodingUtils

Inherits:
Object
  • Object
show all
Defined in:
lib/pdf/reader/encoding_utils.rb

Overview

Utiliy class for some conversions to utf8 (the standard output encoding for pdf-reader). This is not used for general purpose of encoding management while parsing PDFs, that lives in PDF::Reader::Encoding

Constant Summary collapse

UTF16_BOM =

Signature:

  • Array[Integer]

[254, 255]
PDFDOC_CODEPOINTS =

PDFDocEncoding bytes that map to Unicode codepoints differing from their byte value. All other bytes map directly to their Unicode codepoint value (0x00-0x17/0x20-0x7F: ASCII; 0xA1-0xFF: Latin-1, which PDFDocEncoding matches exactly).

{
  0x18 => 0x02D8, # BREVE
  0x19 => 0x02C7, # CARON
  0x1A => 0x02C6, # MODIFIER LETTER CIRCUMFLEX ACCENT
  0x1B => 0x02D9, # DOT ABOVE
  0x1C => 0x02DD, # DOUBLE ACUTE ACCENT
  0x1D => 0x02DB, # OGONEK
  0x1E => 0x02DA, # RING ABOVE
  0x1F => 0x02DC, # SMALL TILDE
  0x80 => 0x2022, # BULLET
  0x81 => 0x2020, # DAGGER
  0x82 => 0x2021, # DOUBLE DAGGER
  0x83 => 0x2026, # HORIZONTAL ELLIPSIS
  0x84 => 0x2014, # EM DASH
  0x85 => 0x2013, # EN DASH
  0x86 => 0x0192, # LATIN SMALL LETTER F WITH HOOK
  0x87 => 0x2044, # FRACTION SLASH
  0x88 => 0x2039, # SINGLE LEFT-POINTING ANGLE QUOTATION MARK
  0x89 => 0x203A, # SINGLE RIGHT-POINTING ANGLE QUOTATION MARK
  0x8A => 0x2212, # MINUS SIGN
  0x8B => 0x2030, # PER MILLE SIGN
  0x8C => 0x201E, # DOUBLE LOW-9 QUOTATION MARK
  0x8D => 0x201C, # LEFT DOUBLE QUOTATION MARK
  0x8E => 0x201D, # RIGHT DOUBLE QUOTATION MARK
  0x8F => 0x2018, # LEFT SINGLE QUOTATION MARK
  0x90 => 0x2019, # RIGHT SINGLE QUOTATION MARK
  0x91 => 0x201A, # SINGLE LOW-9 QUOTATION MARK
  0x92 => 0x2122, # TRADE MARK SIGN
  0x93 => 0xFB01, # LATIN SMALL LIGATURE FI
  0x94 => 0xFB02, # LATIN SMALL LIGATURE FL
  0x95 => 0x0141, # LATIN CAPITAL LETTER L WITH STROKE
  0x96 => 0x0152, # LATIN CAPITAL LIGATURE OE
  0x97 => 0x0160, # LATIN CAPITAL LETTER S WITH CARON
  0x98 => 0x0178, # LATIN CAPITAL LETTER Y WITH DIAERESIS
  0x99 => 0x017D, # LATIN CAPITAL LETTER Z WITH CARON
  0x9A => 0x0131, # LATIN SMALL LETTER DOTLESS I
  0x9B => 0x0142, # LATIN SMALL LETTER L WITH STROKE
  0x9C => 0x0153, # LATIN SMALL LIGATURE OE
  0x9D => 0x0161, # LATIN SMALL LETTER S WITH CARON
  0x9E => 0x017E, # LATIN SMALL LETTER Z WITH CARON
  0xA0 => 0x20AC, # EURO SIGN
}.freeze

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.obj_to_utf8(obj) ⇒ Object

Signature:

  • (untyped) -> untyped



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# File 'lib/pdf/reader/encoding_utils.rb', line 62

def self.obj_to_utf8(obj)
  new.obj_to_utf8(obj)
end

.string_to_utf8(str) ⇒ Object

Signature:

  • (String) -> String



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# File 'lib/pdf/reader/encoding_utils.rb', line 67

def self.string_to_utf8(str)
  new.string_to_utf8(str)
end

Instance Method Details

#obj_to_utf8(obj) ⇒ Object

Recursively convert Hashes, Arrays, and Strings to UTF-8

Signature:

  • (untyped) -> untyped



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# File 'lib/pdf/reader/encoding_utils.rb', line 74

def obj_to_utf8(obj)
  case obj
  when ::Hash then
    {}.tap { |new_hash|
      obj.each do |key, value|
        new_hash[key] = obj_to_utf8(value)
      end
    }
  when Array then
    obj.map { |item| obj_to_utf8(item) }
  when String then
    string_to_utf8(obj)
  else
    obj
  end
end

#string_to_utf8(str) ⇒ Object

Convert a String to UTF-8

Signature:

  • (String) -> String



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# File 'lib/pdf/reader/encoding_utils.rb', line 94

def string_to_utf8(str)
  if has_utf16_bom?(str)
    utf16_to_utf8(str)
  else
    pdfdoc_to_utf8(str)
  end
end