Bug #6249: Process.exec doesn't restore the environment if it fails

• Status: Closed
• Assignee: akr (Akira Tanaka)
• Target version: -
• ruby -v: ruby 1.9.3p125 (2012-02-16 revision 34643) [x86_64-darwin11.3.0]

[john_firebaugh (John Firebaugh)]

ENV["foo"]
=> nil
Process.exec({"foo" => "bar"}, "nonexistent")
Errno::ENOENT: No such file or directory - nonexistent
from (irb):2:in exec' from (irb):2 from /Users/john/.rvm/rubies/ruby-1.9.3-p125/bin/irb:16:in '
ENV["foo"]
=> "bar"

I expected that Process.exec would either use execle or execve, or (if it implements environment modification itself), to manually restore the existing environment upon failure.

[akr (Akira Tanaka)]

2012/4/3 john_firebaugh (John Firebaugh) [e-mail]:

ENV["foo"]
=> nil
Process.exec({"foo" => "bar"}, "nonexistent")
Errno::ENOENT: No such file or directory - nonexistent
from (irb):2:in exec' from (irb):2 from /Users/john/.rvm/rubies/ruby-1.9.3-p125/bin/irb:16:in '
ENV["foo"]
=> "bar"

I expected that Process.exec would either use execle or execve, or (if it implements environment modification itself), to manually restore the existing environment upon failure.

I see.

I think Process.exec should use execve.

Tanaka Akira

[mame (Yusuke Endoh)]

• Status changed from Open to Assigned
• Assignee set to akr (Akira Tanaka)

[akr (Akira Tanaka)]

• Status changed from Assigned to Closed
• % Done changed from 0 to 100

This issue was solved with changeset r35882.
John, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

---

• use execve() to preserve environment variables when exec method is
  failed. [ruby-core:44093] [ruby-trunk - Bug #6249]

• include/ruby/intern.h (rb_exec_arg): add envp_str and envp_buf field
  to store envp of execve().

• process.c (proc_exec_v): takes envp_str as an argument and use it
  for execve().
  (rb_proc_exec_ne): extended version of rb_proc_exec_n().
  (rb_proc_exec_n): use rb_proc_exec_ne().
  (rb_proc_exec): follow proc_exec_v() change.
  (fill_envp_buf_i): new function.
  (rb_exec_arg_fixup): set up envp_str and envp_buf.
  (save_env_i): removed.
  (save_env): removed.
  (rb_run_exec_options_err): don't modify environment variables.
  (rb_exec_err): use rb_proc_exec_ne().