Class: MachO::Headers::MachHeader

Inherits:
MachOStructure show all
Defined in:
lib/macho/headers.rb

Overview

32-bit Mach-O file header structure

Direct Known Subclasses

MachHeader64

Constant Summary collapse

FORMAT =

This constant is part of a private API. You should avoid using this constant if possible, as it may be removed or be changed in the future.

See Also:

"L=7"
SIZEOF =

This constant is part of a private API. You should avoid using this constant if possible, as it may be removed or be changed in the future.

See Also:

28

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from MachOStructure

bytesize, new_from_bin

Constructor Details

#initialize(magic, cputype, cpusubtype, filetype, ncmds, sizeofcmds, flags) ⇒ MachHeader

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a new instance of MachHeader.



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# File 'lib/macho/headers.rb', line 649

def initialize(magic, cputype, cpusubtype, filetype, ncmds, sizeofcmds,
               flags)
  @magic = magic
  @cputype = cputype
  # For now we're not interested in additional capability bits also to be
  # found in the `cpusubtype` field. We only care about the CPU sub-type.
  @cpusubtype = cpusubtype & ~CPU_SUBTYPE_MASK
  @filetype = filetype
  @ncmds = ncmds
  @sizeofcmds = sizeofcmds
  @flags = flags
end

Instance Attribute Details

#cpusubtype ⇒ Integer (readonly)

Returns the CPU subtype of the Mach-O.

Returns:

  • (Integer) —

    the CPU subtype of the Mach-O



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# File 'lib/macho/headers.rb', line 626

def cpusubtype
  @cpusubtype
end

#cputype ⇒ Integer (readonly)

Returns the CPU type of the Mach-O.

Returns:

  • (Integer) —

    the CPU type of the Mach-O



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# File 'lib/macho/headers.rb', line 623

def cputype
  @cputype
end

#filetype ⇒ Integer (readonly)

Returns the file type of the Mach-O.

Returns:

  • (Integer) —

    the file type of the Mach-O



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# File 'lib/macho/headers.rb', line 629

def filetype
  @filetype
end

#flags ⇒ Integer (readonly)

Returns the header flags associated with the Mach-O.

Returns:

  • (Integer) —

    the header flags associated with the Mach-O



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# File 'lib/macho/headers.rb', line 638

def flags
  @flags
end

#magic ⇒ Integer (readonly)

Returns the magic number.

Returns:

  • (Integer) —

    the magic number



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# File 'lib/macho/headers.rb', line 620

def magic
  @magic
end

#ncmds ⇒ Integer (readonly)

Returns the number of load commands in the Mach-O.

Returns:

  • (Integer) —

    the number of load commands in the Mach-O



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# File 'lib/macho/headers.rb', line 632

def ncmds
  @ncmds
end

#sizeofcmds ⇒ Integer (readonly)

Returns the size of all load commands, in bytes, in the Mach-O.

Returns:

  • (Integer) —

    the size of all load commands, in bytes, in the Mach-O



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# File 'lib/macho/headers.rb', line 635

def sizeofcmds
  @sizeofcmds
end

Instance Method Details

#alignment ⇒ Integer

Returns the file's internal alignment.

Returns:

  • (Integer) —

    the file's internal alignment



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# File 'lib/macho/headers.rb', line 735

def alignment
  magic32? ? 4 : 8
end

#bundle? ⇒ Boolean

Returns whether or not the file is of type MH_BUNDLE.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_BUNDLE



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# File 'lib/macho/headers.rb', line 710

def bundle?
  filetype == Headers::MH_BUNDLE
end

#core? ⇒ Boolean

Returns whether or not the file is of type MH_CORE.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_CORE



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# File 'lib/macho/headers.rb', line 690

def core?
  filetype == Headers::MH_CORE
end

#dsym? ⇒ Boolean

Returns whether or not the file is of type MH_DSYM.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_DSYM



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# File 'lib/macho/headers.rb', line 715

def dsym?
  filetype == Headers::MH_DSYM
end

#dylib? ⇒ Boolean

Returns whether or not the file is of type MH_DYLIB.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_DYLIB



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# File 'lib/macho/headers.rb', line 700

def dylib?
  filetype == Headers::MH_DYLIB
end

#dylinker? ⇒ Boolean

Returns whether or not the file is of type MH_DYLINKER.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_DYLINKER



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# File 'lib/macho/headers.rb', line 705

def dylinker?
  filetype == Headers::MH_DYLINKER
end

#executable? ⇒ Boolean

Returns whether or not the file is of type MH_EXECUTE.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_EXECUTE



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# File 'lib/macho/headers.rb', line 680

def executable?
  filetype == Headers::MH_EXECUTE
end

#flag?(flag) ⇒ Boolean

Returns true if flag is present in the header's flag section.

Examples:

puts "this mach-o has position-independent execution" if header.flag?(:MH_PIE)

Parameters:

  • flag (Symbol) —

    a mach header flag symbol

Returns:

  • (Boolean) —

    true if flag is present in the header's flag section



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# File 'lib/macho/headers.rb', line 666

def flag?(flag)
  flag = MH_FLAGS[flag]

  return false if flag.nil?

  flags & flag == flag
end

#fvmlib? ⇒ Boolean

Returns whether or not the file is of type MH_FVMLIB.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_FVMLIB



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# File 'lib/macho/headers.rb', line 685

def fvmlib?
  filetype == Headers::MH_FVMLIB
end

#kext? ⇒ Boolean

Returns whether or not the file is of type MH_KEXT_BUNDLE.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_KEXT_BUNDLE



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# File 'lib/macho/headers.rb', line 720

def kext?
  filetype == Headers::MH_KEXT_BUNDLE
end

#magic32? ⇒ Boolean

Returns true if the Mach-O has 32-bit magic, false otherwise.

Returns:

  • (Boolean) —

    true if the Mach-O has 32-bit magic, false otherwise



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# File 'lib/macho/headers.rb', line 725

def magic32?
  Utils.magic32?(magic)
end

#magic64? ⇒ Boolean

Returns true if the Mach-O has 64-bit magic, false otherwise.

Returns:

  • (Boolean) —

    true if the Mach-O has 64-bit magic, false otherwise



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# File 'lib/macho/headers.rb', line 730

def magic64?
  Utils.magic64?(magic)
end

#object? ⇒ Boolean

Returns whether or not the file is of type MH_OBJECT.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_OBJECT



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# File 'lib/macho/headers.rb', line 675

def object?
  filetype == Headers::MH_OBJECT
end

#preload? ⇒ Boolean

Returns whether or not the file is of type MH_PRELOAD.

Returns:

  • (Boolean) —

    whether or not the file is of type MH_PRELOAD



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# File 'lib/macho/headers.rb', line 695

def preload?
  filetype == Headers::MH_PRELOAD
end

#to_h ⇒ Hash

Returns a hash representation of this MachO::Headers::MachHeader.

Returns:



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# File 'lib/macho/headers.rb', line 740

def to_h
  {
    "magic" => magic,
    "magic_sym" => MH_MAGICS[magic],
    "cputype" => cputype,
    "cputype_sym" => CPU_TYPES[cputype],
    "cpusubtype" => cpusubtype,
    "cpusubtype_sym" => CPU_SUBTYPES[cputype][cpusubtype],
    "filetype" => filetype,
    "filetype_sym" => MH_FILETYPES[filetype],
    "ncmds" => ncmds,
    "sizeofcmds" => sizeofcmds,
    "flags" => flags,
    "alignment" => alignment,
  }.merge super
end