Class: Webloc

Inherits:
Object
  • Object
show all
Defined in:
lib/webloc.rb,
lib/webloc/version.rb

Defined Under Namespace

Classes: CorruptedFileError, EmptyFileError, FileNotFoundError, InvalidFormatError, WeblocError

Constant Summary collapse

VERSION = 
"0.3.1"

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(url) ⇒ Webloc

Returns a new instance of Webloc.

Raises:

  • (ArgumentError) 


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# File 'lib/webloc.rb', line 12

def initialize(url)
  raise ArgumentError, "URL cannot be nil or empty" if url.nil? || url.empty?
  @url = url
end

Instance Attribute Details

#url ⇒ Object

Returns the value of attribute url.



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# File 'lib/webloc.rb', line 10

def url
  @url
end

Class Method Details

.load(filename) ⇒ Object

Raises:



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# File 'lib/webloc.rb', line 17

def self.load(filename)
  raise FileNotFoundError, "File not found: #{filename}" unless File.exist?(filename)
  
  begin
    data = File.read(filename)
  rescue => e
    raise FileNotFoundError, "Unable to read file '#{filename}': #{e.message}"
  end
  
  raise EmptyFileError, "File is empty: #{filename}" if data.empty?
  
  data = data.force_encoding('binary') rescue data
  url = nil
  
  if data !~ /\<plist/
    # Handle binary plist format
    url = parse_binary_format(data, filename)
  else
    # Handle XML plist format
    url = parse_xml_format(filename)
  end
  
  raise CorruptedFileError, "No URL found in webloc file: #{filename}" if url.nil? || url.empty?
  new(url)
end

Instance Method Details

#data ⇒ Object 



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# File 'lib/webloc.rb', line 95

def data
  # PLIST HEADER
  @data = "bplist\x30\x30".bytes

  # PLIST OBJECT TABLE
  @data += "\xD1\x01\x02".bytes   # object 1 is a dictionary
  @data += "SURL".bytes           # object 2

  length_suffix = @url.length > 255 ? "\x11" : "\x10"
  @data += ("\x5f" + length_suffix).bytes       # object 3 is an ASCII string with a variable length length encoding (I know..)
                            #   .. the '0' in \x10 denotes the length can be encoded within 2**0 bytes (i.e. 1)
                            #   .. the '1' in \x11 denotes the length can be encoded within 2**1 bytes (i.e. 2)
  
  if @url.length > 255
    @data += [@url.length].pack('S>').bytes
  else
    @data += [@url.length].pack('C').bytes
  end
  @data += @url.bytes             # and finally the URL itself

  # This is the offset table
  @data += "\x08\x0B\x0F".bytes   # so objects at 0x08, 0x0b and 0x0f

  # PLIST TRAILER
  # Bytes 0-4 are unused
  @data += "\x00\x00\x00\x00\x00".bytes
  # Byte 5 is the sort version
  @data += "\x00".bytes
  # Byte 6 is how many bytes are needed for each offset table offset
  @data += "\x01".bytes
  @data += "\x01".bytes
  # Bytes 8-15 are how many objects are contained in the plist
  @data += "\x00\x00\x00\x00\x00\x00\x00\x03".bytes
  # Bytes 16-23 are for an offset from the offset table
  @data += "\x00\x00\x00\x00\x00\x00\x00\x00".bytes
  # Bytes 24-31 denote the position of the offset table from the start of the file
  @data += "\x00\x00\x00\x00\x00\x00".bytes + [@url.length + 18].pack('S>').bytes

  @data = @data.pack('C*')
end

#save(filename) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/webloc.rb', line 136

def save(filename)
  raise ArgumentError, "Filename cannot be nil or empty" if filename.nil? || filename.empty?
  
  begin
    File.open(filename, 'wb') { |f| f.write data }
  rescue => e
    raise WeblocError, "Failed to save webloc file '#{filename}': #{e.message}"
  end
end