Class: Bfd::Target

Inherits:
Object
  • Object
show all
Defined in:
lib/BFD.rb

Constant Summary collapse

FORMAT_CORE =

core dump

'core'
FORMAT_OBJECT =

linkable (executable, shared library) or relocatable object file

'object'
FORMAT_ARCHIVE =

library archive (.ar)

'archive'
FORMAT_UNKNOWN =

unrecognized/unsupported file

'unknown'
FORMATS =

BFD object type

[ FORMAT_UNKNOWN, FORMAT_CORE, FORMAT_OBJECT, FORMAT_ARCHIVE ]
FLAVOURS =

BFD file format. Defined in /usr/include/bfd.h : enum bfd_flavour

%w{ unknown aout coff ecoff xcoff elf ieee nlm oasys tekhex srec
verilog ihex som os0k versados msdos ovax evax mmo mach_o
pef pef_xlib sym }
ENDIAN =

Byte order. Defined in /usr/include/bfd.h : enum bfd_endian

%w{ big little unknown }
FLAG_EXEC = 
'EXEC_P'
FLAG_DYNAMIC = 
'DYNAMIC'
FLAGS =

File Format Flags. Defined in /usr/include/bfd.h : struct bfd

{ 0x0001 => 'HAS_RELOC',
0x0002 => FLAG_EXEC,
0x0004 => 'LINEN',
0x0008 => 'DEBUG',
0x0010 => 'SYMS',
0x0020 => 'LOCALS',
0x0040 => FLAG_DYNAMIC,
0x0080 => 'WP_TEXT',
0x0100 => 'D_PAGED',
0x0200 => 'IS_RELAXABLE',
0x0400 => 'TRADITIONAL_FORMAT',
0x0800 => 'IN_MEMORY',
0x1000 => 'HAS_LOAD_PAGE',
0x2000 => 'LINKER_CREATED',
0x4000 => 'DETERMINISTIC_OUTPUT' }

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#temp_file ⇒ Object

Temporary file used if Target is instantiated from a buffer. BFD does not operate on memory locations and requires a file descriptor; a temporary file is therefore created on the filesystem when Target.from_buffer is called. The temp file is deleted when Target.close is called.



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# File 'lib/BFD.rb', line 83

def temp_file
  @temp_file
end

Class Method Details

.from_buffer(buf, args = {}) {|bfd| ... } ⇒ Object

Instantiate target from a buffer instead of from a file. Note: this creates a temporary file which MUST be closed and unlinked by calling Target.close, or by passing a block to this method.

Yields:

  • (bfd) 


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# File 'lib/BFD.rb', line 103

def self.from_buffer(buf, args={})

  f = Tempfile.new( 'bfd_target' )
  path = f.path
  f.close

  f = File.open(path, 'wb')
  f.write(buf)
  f.rewind

  bfd = ext_new(path, args)
  raise "Unable to construct BFD" if not bfd

  if not block_given?
    @temp_file = f
    return bfd
  end

  # yield bfd object, then close temp file
  yield bfd
  f.close
  File.unlink(path)
  nil
end

.new(target, args = {}) {|bfd| ... } ⇒ Object

Create a new Target from a path or IO object. This just wraps for ext_new and provides a default value for args. NOTE: target should either be the path to a file or an IO object with a valid read-only (i.e. opened with ‘rb’ flags) file descriptor returned by fileno(). File descriptors opened for write (‘wb’) will be rejected by libbfd.

Yields:

  • (bfd) 


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# File 'lib/BFD.rb', line 92

def self.new(target, args={})
  bfd = ext_new(target, args)
  yield bfd if (bfd and block_given?)
  return bfd
end

Instance Method Details

#close ⇒ Object

Free any resources used by BFD Target



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# File 'lib/BFD.rb', line 131

def close
  @temp_file ||= nil

  if @temp_file
    path = @temp_file.path
    @temp_file.close
    File.unlink(path)
    @temp_file = nil
  end
end

#endian ⇒ Object

Return the byte order of the target. See raw_endian.



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# File 'lib/BFD.rb', line 204

def endian
  ENDIAN[@raw_endian]
end

#flavour ⇒ Object

Return the target file format. See raw_flavour.



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# File 'lib/BFD.rb', line 196

def flavour
  FLAVOURS[@raw_flavour]
end

#format_flags ⇒ Object

Return an array of the names of the file format flags that are set. See raw_format_flags and type_flags.



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# File 'lib/BFD.rb', line 146

def format_flags
  flag_strings(@raw_format_flags)
end

#inspect ⇒ Object 



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# File 'lib/BFD.rb', line 224

def inspect
  "#{self.to_s} : #{self.flavour} #{@format} (#{@type} #{endian}-endian)"
end

#is_executable? ⇒ Boolean

Is target a standalone executable

Returns:

  • (Boolean) 


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# File 'lib/BFD.rb', line 160

def is_executable?
  @format == FORMAT_OBJECT and format_flags.include? FLAG_EXEC
end

#is_relocatable_object? ⇒ Boolean

Is target a relocatable object (not an executable or .so)

Returns:

  • (Boolean) 


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# File 'lib/BFD.rb', line 175

def is_relocatable_object?
  @format == FORMAT_OBJECT and (not format_flags.include? FLAG_DYNAMIC) and
                               (not format_flags.include? FLAG_EXEC)
end

#is_shared_object? ⇒ Boolean

Is target a shared library file (.so)

Returns:

  • (Boolean) 


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# File 'lib/BFD.rb', line 167

def is_shared_object?
  @format == FORMAT_OBJECT and format_flags.include? FLAG_DYNAMIC and
                               (not format_flags.include? FLAG_EXEC)
end

#section_for_vma(vma) ⇒ Object

Return the Bfd::Section in the target that contains vma, or nil.



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# File 'lib/BFD.rb', line 212

def section_for_vma(vma)
  @sections.values.each do |s|
    return s if (vma >= s.vma and vma < (s.vma + s.size))
  end

  return nil
end

#to_s ⇒ Object 



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# File 'lib/BFD.rb', line 220

def to_s
  "[#{@id}] #{@filename}"
end

#type_flags ⇒ Object

Return an array of the names of the target type flags that are set. Note: These are the ‘backend’ flags for the BFD target type, and seem to be a list of the flags available for the target type, not the list of flags which are set. The format_flags field should always be used to determine the flags which are set for a BFD target. See raw_type_flags and format_flags.



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# File 'lib/BFD.rb', line 188

def type_flags()
  flag_strings(@raw_type_flags)
end

#valid? ⇒ Boolean

Is Target a valid BFD object (i.e. did BFD successfully parse it)

Returns:

  • (Boolean) 


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# File 'lib/BFD.rb', line 153

def valid?
  @format != FORMAT_UNKNOWN
end