Class: Fontisan::Type1::PFBParser

Inherits:
Object
  • Object
show all
Defined in:
lib/fontisan/type1/pfb_parser.rb

Overview

Parser for PFB (Printer Font Binary) format

[‘PFBParser`](lib/fontisan/type1/pfb_parser.rb) parses the binary PFB format used for storing Adobe Type 1 fonts, primarily on Windows systems.

The PFB format consists of binary chunks marked with special codes:

  • 0x8001: ASCII text chunk

  • 0x8002: Binary data chunk (usually encrypted)

  • 0x8003: End of file marker

Each chunk (except EOF) has a 4-byte little-endian length prefix.

Examples:

Parse a PFB file

parser = Fontisan::Type1::PFBParser.new
result = parser.parse(File.binread('font.pfb'))
puts result.ascii_parts    # => ["%!PS-AdobeFont-1.0...", ...]
puts result.binary_parts   # => [encrypted_binary_data, ...]

See Also:

Constant Summary collapse

ASCII_CHUNK =

PFB chunk markers

0x8001
BINARY_CHUNK = 
0x8002
EOF_CHUNK = 
0x8003

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#ascii_parts ⇒ Array<String> (readonly)

Returns ASCII text parts.

Returns:

  • (Array<String>) —

    ASCII text parts



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# File 'lib/fontisan/type1/pfb_parser.rb', line 31

def ascii_parts
  @ascii_parts
end

#binary_parts ⇒ Array<String> (readonly)

Returns Binary data parts.

Returns:

  • (Array<String>) —

    Binary data parts



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# File 'lib/fontisan/type1/pfb_parser.rb', line 34

def binary_parts
  @binary_parts
end

Class Method Details

.pfb_file?(data) ⇒ Boolean

Check if this appears to be a PFB file

Examples:

Check if file is PFB format

if Fontisan::Type1::PFBParser.pfb_file?(data)
  # Handle PFB format
end

Parameters:

  • data (String) —

    Binary data to check

Returns:

  • (Boolean) —

    True if data starts with PFB marker



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# File 'lib/fontisan/type1/pfb_parser.rb', line 120

def self.pfb_file?(data)
  return false if data.nil? || data.length < 2

  # PFB marker is big-endian (first byte is high byte)
  marker = (data.getbyte(0) << 8) | data.getbyte(1)
  [ASCII_CHUNK, BINARY_CHUNK].include?(marker)
end

Instance Method Details

#ascii_text ⇒ String

Get all ASCII parts concatenated

Returns:

  • (String) —

    All ASCII parts joined together



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# File 'lib/fontisan/type1/pfb_parser.rb', line 93

def ascii_text
  @ascii_parts.join
end

#binary_data ⇒ String

Get all binary parts concatenated

Returns:

  • (String) —

    All binary parts joined together



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# File 'lib/fontisan/type1/pfb_parser.rb', line 100

def binary_data
  @binary_parts.join
end

#parse(data) ⇒ PFBParser

Parse PFB format data

Parameters:

  • data (String) —

    Binary PFB data

Returns:

Raises:

  • (ArgumentError) —

    If data is nil or empty

  • (Fontisan::Error) —

    If PFB format is invalid



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# File 'lib/fontisan/type1/pfb_parser.rb', line 42

def parse(data)
  raise ArgumentError, "Data cannot be nil" if data.nil?
  raise ArgumentError, "Data cannot be empty" if data.empty?

  @ascii_parts = []
  @binary_parts = []

  offset = 0
  chunk_index = 0

  while offset < data.length
    # Check for chunk marker (must have at least 2 bytes)
    if offset + 2 > data.length
      raise Fontisan::Error,
            "Invalid PFB: incomplete chunk header at offset #{offset}"
    end

    # Read chunk marker (big-endian)
    marker = (data.getbyte(offset) << 8) |
      data.getbyte(offset + 1)
    offset += 2

    case marker
    when ASCII_CHUNK
      chunk = read_chunk(data, offset, chunk_index, "ASCII")
      @ascii_parts << chunk[:data]
      offset = chunk[:next_offset]
      chunk_index += 1

    when BINARY_CHUNK
      chunk = read_chunk(data, offset, chunk_index, "binary")
      @binary_parts << chunk[:data]
      offset = chunk[:next_offset]
      chunk_index += 1

    when EOF_CHUNK
      # End of file - no more chunks
      break

    else
      raise Fontisan::Error,
            "Invalid PFB: unknown chunk marker 0x#{marker.to_s(16).upcase} at offset #{offset - 2}"
    end
  end

  self
end

#parsed? ⇒ Boolean

Check if parser has parsed data

Returns:

  • (Boolean) —

    True if data has been parsed



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# File 'lib/fontisan/type1/pfb_parser.rb', line 107

def parsed?
  !@ascii_parts.nil? && !@binary_parts.nil?
end