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# -*- encoding: binary -*-

# This class and its members can be considered a stable interface
# and will not change in a backwards-incompatible fashion between
# releases of Unicorn.  You may need to access it in the
# before_fork/after_fork hooks.  See the Unicorn::Configurator RDoc
# for examples.
class Unicorn::Worker < Struct.new(:nr, :tmp, :switched)

  # worker objects may be compared to just plain numbers
  def ==(other_nr)
    self.nr == other_nr
  end

  # Changes the worker process to the specified +user+ and +group+
  # This is only intended to be called from within the worker
  # process from the +after_fork+ hook.  This should be called in
  # the +after_fork+ hook after any priviledged functions need to be
  # run (e.g. to set per-worker CPU affinity, niceness, etc)
  #
  # Any and all errors raised within this method will be propagated
  # directly back to the caller (usually the +after_fork+ hook.
  # These errors commonly include ArgumentError for specifying an
  # invalid user/group and Errno::EPERM for insufficient priviledges
  def user(user, group = nil)
    # we do not protect the caller, checking Process.euid == 0 is
    # insufficient because modern systems have fine-grained
    # capabilities.  Let the caller handle any and all errors.
    uid = Etc.getpwnam(user).uid
    gid = Etc.getgrnam(group).gid if group
    Unicorn::Util.chown_logs(uid, gid)
    tmp.chown(uid, gid)
    if gid && Process.egid != gid
      Process.initgroups(user, gid)
      Process::GID.change_privilege(gid)
    end
    Process.euid != uid and Process::UID.change_privilege(uid)
    self.switched = true
  end
end