Process.euid=/Process.egid= don't accept strings

[djberg96]

Ruby 3.0.2 allows a string for Process.euid=, and will (I assume) do a user lookup in that case:

# OS X
Process.euid = "test" # => can't find user for test (ArgumentError)
Process.euid = "dberger" # => "dberger"

But using Truffleruby 22.0.0.2:

Process.euid = "test" # => undefined method `to_int' for "test":String
Process.euid = "dberger" # => undefined method `to_int' for "dberger":String

[chrisseaton]

Seems an ancient feature.

ruby/ruby@9bf9b3e

But it's never been properly specified - see here it specifies that it raises an error if not given an integer, but then also specifies that you can't set it to root, using the string, but in order to trigger an unrelated error.

https://github.com/ruby/spec/blob/a0f1a08f38d13cc6491cd1192958046bceceaf39/core/process/euid_spec.rb#L17-L45

Implementation would go here.

truffleruby/src/main/ruby/truffleruby/core/process.rb

Lines 404 to 430 in 0e73061

	def self.euid=(uid)
	# the 4 rescue clauses below are needed
	# until respond_to? can be used to query the implementation of methods attached via FFI
	# atm respond_to returns true if a method is attached but not implemented on the platform
	uid = Truffle::Type.coerce_to uid, Integer, :to_int
	begin
	ret = Truffle::POSIX.setresuid(-1, uid, -1)
	rescue NotImplementedError
	begin
	ret = Truffle::POSIX.setreuid(-1, uid)
	rescue NotImplementedError
	begin
	ret = Truffle::POSIX.seteuid(uid)
	rescue NotImplementedError
	if Process.uid == uid
	ret = Truffle::POSIX.setuid(uid)
	else
	raise NotImplementedError
	end
	end
	end
	end
	Errno.handle if ret == -1
	uid
	end

Should be relatively easy to fix, could be a good beginner project. First thing would be specifications and then an implementation.

[eregon]

Converting the user name to a uid can be done with Etc.getpwnam(user).uid, which is what fileutils does:

truffleruby/lib/mri/fileutils.rb

Lines 1110 to 1111 in 0e73061

	require 'etc'
	Etc.getpwnam(user) ? Etc.getpwnam(user).uid : nil

That means it needs require 'etc' but that seems fine since it's a rarely-used method.

[djberg96]

Note that Process.egid= has the same issue.

[andrykonchin]

Looks like the issue is fixed and the PR is merged.