Module: Xtendr

Included in:
XtendrProxy
Defined in:
lib/xtendr.rb

Defined Under Namespace

Modules: FFI

Instance Method Summary collapse

Instance Method Details

#getx(attribute, *opts) { ... } ⇒ String?

Get the value of an extended attribute for the current object. Calls ‘#to_s` on self to get the path to the file the attribute is set on.

Yields:

  • Block is run when the attribute is not found.



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# File 'lib/xtendr.rb', line 22

def getx(attribute, *opts)
  getx! attribute, *opts
rescue Errno::ENOATTR
  block_given? ? yield : nil
end

#getx!(attribute, *opts) ⇒ String

Get the value of an extended attribute, raising an error if the attribute is not found.

The bang version of getx works the the same way as ‘getx`, exept that when the attribute is not found. In that case, rather than returning `nil`, an ENOATTR error is raised.

Raises:

  • (Errno::ENOATTR) —

    Describes the attribute that couldn’t be located.



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# File 'lib/xtendr.rb', line 38

def getx!(attribute, *opts)
  options = opts.include?(:no_follow) ? 1 : 0
  len = FFI.getxattr(self.to_s, attribute, nil, 0, 0, options)
  raise_error(attribute, ::FFI::LastError::error) if len < 0
  buffer = ::FFI::Buffer.alloc_out(len)
  FFI.getxattr(self.to_s, attribute, buffer, buffer.size, 0, options)
  buffer.get_string(0, buffer.size)
end

#listx ⇒ Array<String>

List all of the extended attribute for the object.



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# File 'lib/xtendr.rb', line 78

def listx
  len = FFI.listxattr(self.to_s, nil, 0, 0)
  buffer = ::FFI::Buffer.alloc_out(len)
  FFI.listxattr(self.to_s, buffer, buffer.size, 0)
  buffer.get_bytes(0, buffer.size).split("\0")
end

#remove_allx ⇒ Object

Remove all extended file attributes from the object



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# File 'lib/xtendr.rb', line 94

def remove_allx
  listx.each do |attribute|
    removex(attribute)
  end
end

#removex(attribute) ⇒ nil

Removes the given extended attribute from the filesystem object.



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# File 'lib/xtendr.rb', line 89

def removex(attribute)
  FFI.removexattr(self.to_s, attribute, 0)
end

#setx(attribute, value, *opts) ⇒ nil

Set an extended attribute on a filesystem object.

:create

Raises an error if the attribute already exists.



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# File 'lib/xtendr.rb', line 56

def setx(attribute, value, *opts)
  retval = FFI.setxattr(self.to_s, attribute, value, value.size, 0, setx_options(*opts))
  raise_error(nil, ::FFI::LastError::error) if retval < 0
end