Class: Cabriolet::Models::HLPHeader

Inherits:
Object
  • Object
show all
Defined in:
lib/cabriolet/models/hlp_header.rb

Overview

QuickHelp database header model

Represents the metadata of a QuickHelp help database (.HLP file). HLP files contain topics, context strings, and optional compression (keyword dictionary and Huffman coding).

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(magic: nil, version: 2, attributes: 0, control_character: 0x3A, topic_count: 0, context_count: 0, display_width: 80, predefined_ctx_count: 0, database_name: "", topic_index_offset: 0, context_strings_offset: 0, context_map_offset: 0, keywords_offset: 0, huffman_tree_offset: 0, topic_text_offset: 0, database_size: 0, filename: nil) ⇒ HLPHeader

Initialize QuickHelp database header

Parameters:

  • magic (String) (defaults to: nil) —

    Magic number (should be 0x4C 0x4E)

  • version (Integer) (defaults to: 2) —

    Format version (should be 2)

  • attributes (Integer) (defaults to: 0) —

    Attribute flags

  • control_character (Integer) (defaults to: 0x3A) —

    Control character (usually ':' or 0xFF)

  • topic_count (Integer) (defaults to: 0) —

    Number of topics

  • context_count (Integer) (defaults to: 0) —

    Number of context strings

  • display_width (Integer) (defaults to: 80) —

    Display width in characters

  • database_name (String) (defaults to: "") —

    Database name for external links



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# File 'lib/cabriolet/models/hlp_header.rb', line 27

def initialize(
  magic: nil,
  version: 2,
  attributes: 0,
  control_character: 0x3A,
  topic_count: 0,
  context_count: 0,
  display_width: 80,
  predefined_ctx_count: 0,
  database_name: "",
  topic_index_offset: 0,
  context_strings_offset: 0,
  context_map_offset: 0,
  keywords_offset: 0,
  huffman_tree_offset: 0,
  topic_text_offset: 0,
  database_size: 0,
  filename: nil
)
  @magic = magic || Binary::HLPStructures::SIGNATURE
  @version = version
  @attributes = attributes
  @control_character = control_character
  @topic_count = topic_count
  @context_count = context_count
  @display_width = display_width
  @predefined_ctx_count = predefined_ctx_count
  @database_name = database_name
  @topic_index_offset = topic_index_offset
  @context_strings_offset = context_strings_offset
  @context_map_offset = context_map_offset
  @keywords_offset = keywords_offset
  @huffman_tree_offset = huffman_tree_offset
  @topic_text_offset = topic_text_offset
  @database_size = database_size
  @filename = filename

  # Collections
  @topics = []
  @contexts = []
  @context_map = []
  @keywords = []
  @huffman_tree = nil
end

Instance Attribute Details

#attributes ⇒ Object

Returns the value of attribute attributes.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def attributes
  @attributes
end

#context_count ⇒ Object

Returns the value of attribute context_count.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def context_count
  @context_count
end

#context_map ⇒ Object

Topics and context data



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# File 'lib/cabriolet/models/hlp_header.rb', line 15

def context_map
  @context_map
end

#context_map_offset ⇒ Object

Returns the value of attribute context_map_offset.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def context_map_offset
  @context_map_offset
end

#context_strings_offset ⇒ Object

Returns the value of attribute context_strings_offset.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def context_strings_offset
  @context_strings_offset
end

#contexts ⇒ Object

Topics and context data



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# File 'lib/cabriolet/models/hlp_header.rb', line 15

def contexts
  @contexts
end

#control_character ⇒ Object

Returns the value of attribute control_character.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def control_character
  @control_character
end

#database_name ⇒ Object

Returns the value of attribute database_name.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def database_name
  @database_name
end

#database_size ⇒ Object

Returns the value of attribute database_size.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def database_size
  @database_size
end

#display_width ⇒ Object

Returns the value of attribute display_width.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def display_width
  @display_width
end

#filename ⇒ Object

Returns the value of attribute filename.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def filename
  @filename
end

#huffman_tree ⇒ Object

Returns the value of attribute huffman_tree.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def huffman_tree
  @huffman_tree
end

#huffman_tree_offset ⇒ Object

Returns the value of attribute huffman_tree_offset.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def huffman_tree_offset
  @huffman_tree_offset
end

#keywords ⇒ Object

Returns the value of attribute keywords.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def keywords
  @keywords
end

#keywords_offset ⇒ Object

Returns the value of attribute keywords_offset.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def keywords_offset
  @keywords_offset
end

#magic ⇒ Object

Returns the value of attribute magic.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def magic
  @magic
end

#predefined_ctx_count ⇒ Object

Returns the value of attribute predefined_ctx_count.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def predefined_ctx_count
  @predefined_ctx_count
end

#topic_count ⇒ Object

Returns the value of attribute topic_count.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def topic_count
  @topic_count
end

#topic_index_offset ⇒ Object

Returns the value of attribute topic_index_offset.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def topic_index_offset
  @topic_index_offset
end

#topic_text_offset ⇒ Object

Returns the value of attribute topic_text_offset.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def topic_text_offset
  @topic_text_offset
end

#topics ⇒ Object

Topics and context data



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# File 'lib/cabriolet/models/hlp_header.rb', line 15

def topics
  @topics
end

#version ⇒ Object

Returns the value of attribute version.



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# File 'lib/cabriolet/models/hlp_header.rb', line 11

def version
  @version
end

Instance Method Details

#case_sensitive? ⇒ Boolean

Check if case-sensitive context strings

Returns:

  • (Boolean) —

    true if case-sensitive



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# File 'lib/cabriolet/models/hlp_header.rb', line 85

def case_sensitive?
  @attributes.anybits?(Binary::HLPStructures::Attributes::CASE_SENSITIVE)
end

#control_char ⇒ String

Get control character as string

Returns:

  • (String) —

    control character



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# File 'lib/cabriolet/models/hlp_header.rb', line 113

def control_char
  @control_character.chr(Encoding::ASCII)
end

#db_name ⇒ String

Get database name without null padding

Returns:

  • (String) —

    trimmed database name



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# File 'lib/cabriolet/models/hlp_header.rb', line 120

def db_name
  @database_name.split("\x00").first || ""
end

#has_huffman? ⇒ Boolean

Check if Huffman compression is used

Returns:

  • (Boolean) —

    true if Huffman tree present



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# File 'lib/cabriolet/models/hlp_header.rb', line 106

def has_huffman?
  @huffman_tree_offset.positive? && !@huffman_tree.nil?
end

#has_keywords? ⇒ Boolean

Check if keyword compression is used

Returns:

  • (Boolean) —

    true if keywords present



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# File 'lib/cabriolet/models/hlp_header.rb', line 99

def has_keywords?
  @keywords_offset.positive? && !@keywords.empty?
end

#locked? ⇒ Boolean

Check if database is locked (cannot be decoded by HELPMAKE)

Returns:

  • (Boolean) —

    true if locked



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# File 'lib/cabriolet/models/hlp_header.rb', line 92

def locked?
  @attributes.anybits?(Binary::HLPStructures::Attributes::LOCKED)
end

#valid? ⇒ Boolean

Check if header is valid

Returns:

  • (Boolean) —

    true if header appears valid



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# File 'lib/cabriolet/models/hlp_header.rb', line 75

def valid?
  @magic == Binary::HLPStructures::SIGNATURE &&
    @version == 2 &&
    @topic_count >= 0 &&
    @context_count >= 0
end