t/test-terminal.perl

   1 #!/usr/bin/perl
   2 use strict;
   3 use warnings;
   4 use IO::Pty;
   5 use File::Copy;
   6
   7 # Run @$argv in the background with stdio redirected to $out and $err.
   8 sub start_child {
   9         my ($argv, $out, $err) = @_;
  10         my $pid = fork;
  11         if (not defined $pid) {
  12                 die "fork failed: $!"
  13         } elsif ($pid == 0) {
  14                 open STDOUT, ">&", $out;
  15                 open STDERR, ">&", $err;
  16                 close $out;
  17                 exec(@$argv) or die "cannot exec '$argv->[0]': $!"
  18         }
  19         return $pid;
  20 }
  21
  22 # Wait for $pid to finish.
  23 sub finish_child {
  24         # Simplified from wait_or_whine() in run-command.c.
  25         my ($pid) = @_;
  26
  27         my $waiting = waitpid($pid, 0);
  28         if ($waiting < 0) {
  29                 die "waitpid failed: $!";
  30         } elsif ($? & 127) {
  31                 my $code = $? & 127;
  32                 warn "died of signal $code";
  33                 return $code - 128;
  34         } else {
  35                 return $? >> 8;
  36         }
  37 }
  38
  39 sub xsendfile {
  40         my ($out, $in) = @_;
  41
  42         # Note: the real sendfile() cannot read from a terminal.
  43
  44         # It is unspecified by POSIX whether reads
  45         # from a disconnected terminal will return
  46         # EIO (as in AIX 4.x, IRIX, and Linux) or
  47         # end-of-file.  Either is fine.
  48         copy($in, $out, 4096) or $!{EIO} or die "cannot copy from child: $!";
  49 }
  50
  51 sub copy_stdio {
  52         my ($out, $err) = @_;
  53         my $pid = fork;
  54         defined $pid or die "fork failed: $!";
  55         if (!$pid) {
  56                 close($out);
  57                 xsendfile(\*STDERR, $err);
  58                 exit 0;
  59         }
  60         close($err);
  61         xsendfile(\*STDOUT, $out);
  62         finish_child($pid) == 0
  63                 or exit 1;
  64 }
  65
  66 if ($#ARGV < 1) {
  67         die "usage: test-terminal program args";
  68 }
  69 my $master_out = new IO::Pty;
  70 my $master_err = new IO::Pty;
  71 my $pid = start_child(\@ARGV, $master_out->slave, $master_err->slave);
  72 close $master_out->slave;
  73 close $master_err->slave;
  74 copy_stdio($master_out, $master_err);
  75 exit(finish_child($pid));