# $Id$

package PerlACE::Process;

use strict;
use POSIX "sys_wait_h";
use Cwd;
use File::Basename;
use Config;

###############################################################################

###  Grab signal names

my @signame;

if (defined $Config{sig_name}) {
    my $i = 0;
    foreach my $name (split (' ', $Config{sig_name})) {
        $signame[$i] = $name;
        $i++;
    }
}
else {
    my $i;
    for ($i = 0; $i < 255; ++$i) {
        $signame[$i] = $i;
    }
}

###############################################################################

### Constructor and Destructor

sub new
{
    my $proto = shift;
    my $class = ref ($proto) || $proto;
    my $self = {};

    $self->{RUNNING} = 0;
    $self->{IGNOREEXESUBDIR} = 0;
    $self->{PROCESS} = undef;
    $self->{EXECUTABLE} = shift;
    $self->{ARGUMENTS} = shift;
    $self->{VALGRIND_CMD} = $ENV{"ACE_RUN_VALGRIND_CMD"};

    if (!defined $PerlACE::Process::WAIT_DELAY_FACTOR) {
         if (defined $self->{PURIFY_CMD}) {
           $PerlACE::Process::WAIT_DELAY_FACTOR = 10;
         }
         elsif (defined $self->{VALGRIND_CMD}) {
           $PerlACE::Process::WAIT_DELAY_FACTOR = 5;
         }
         else {
           $PerlACE::Process::WAIT_DELAY_FACTOR = 1;
        }
    }

    bless ($self, $class);
    return $self;
}

sub DESTROY
{
    my $self = shift;

    if ($self->{RUNNING} == 1) {
        print STDERR "ERROR: <", $self->{EXECUTABLE},
                     "> still running upon object destruction\n";
        $self->Kill ();
    }
}

###############################################################################

### Some Accessors

sub Executable
{
    my $self = shift;

    if (@_ != 0) {
        $self->{EXECUTABLE} = shift;
    }

    my $executable = $self->{EXECUTABLE};

    if ($self->{IGNOREEXESUBDIR}) {
        return $executable;
    }

    my $basename = basename ($executable);
    my $dirname = dirname ($executable). '/';

    $executable = $dirname.$PerlACE::Process::ExeSubDir.$basename;

    return $executable;
}

sub Arguments
{
    my $self = shift;

    if (@_ != 0) {
        $self->{ARGUMENTS} = shift;
    }

    return $self->{ARGUMENTS};
}

sub CommandLine ()
{
    my $self = shift;

    my $commandline = $self->Executable ();

    if (defined $self->{REMOTEINFO}) {
      my($method)   = $self->{REMOTEINFO}->{method};
      my($username) = $self->{REMOTEINFO}->{username};
      my($remote)   = $self->{REMOTEINFO}->{hostname};
      my($exepath)  = $self->{REMOTEINFO}->{exepath};
      my($libpath)  = $self->{REMOTEINFO}->{libpath};
      my($exe)      = (defined $exepath ?
                        "$exepath/" . basename($commandline) : $commandline);
      $commandline  = "$method -l $username $remote \"";
      if (defined $libpath) {
        my($csh) = (defined $self->{REMOTEINFO}->{shell} &&
                            $self->{REMOTEINFO}->{shell} =~ /csh/);
        foreach my $pvar ('LD_LIBRARY_PATH', 'LIBPATH', 'SHLIB_PATH') {
          if ($csh) {
            $commandline .= "if (! \\\$?$pvar) setenv $pvar; " .
                            "setenv $pvar $libpath:\\\$$pvar; ";
          }
          else {
            $commandline .= "$pvar=$libpath:\\\$$pvar; export $pvar; ";
          }
        }
        my($env) = $self->{REMOTEINFO}->{env};
        if (defined $env) {
          foreach my $pvar (keys %$env) {
            if ($csh) {
              $commandline .= "setenv $pvar $$env{$pvar}; ";
            }
            else {
              $commandline .= "$pvar=$$env{$pvar}; export $pvar; ";
            }
          }
        }
      }
      $commandline .= $exe;
    }

    if (defined $self->{ARGUMENTS}) {
        $commandline .= ' '.$self->{ARGUMENTS};
    }

    # Avoid modifying TAO/tests run_test.pl scripts by using the
    # ACE_RUNTEST_ARGS environment variable to append command line
    # arguments.
    if ($^O eq "nonstop_kernel") {
        my $global_args = $ENV{"ACE_RUNTEST_ARGS"};
        if ((length($global_args) > 0)
            && ($commandline !~ /tao_idl/)) {
            $commandline = $commandline
                           . ' '
                           . $global_args;
        }
    }

    if (defined $self->{REMOTEINFO}) {
      $commandline .= '"';
    }

    return $commandline;
}

sub IgnoreExeSubDir
{
    my $self = shift;

    if (@_ != 0) {
        $self->{IGNOREEXESUBDIR} = shift;
    }

    return $self->{IGNOREEXESUBDIR};
}

sub RemoteInformation
{
  my($self)   = shift;
  my(%params) = @_;

  ## Valid keys for %params
  ##  hostname - The remote hostname
  ##  method   - either rsh or ssh
  ##  username - The remote user name
  ##  exepath  - The remote path to the executable
  ##  shell    - The shell of the remote user
  ##  libpath  - A library path for libraries required by the executable
  ##  env      - A hash reference of name value pairs to be set in the
  ##             environment prior to executing the executable.
  ##
  ## At a minimum, the user must provide the remote hostname.

  if (defined $params{'hostname'}) {
    my(@pwd) = getpwuid($<);
    $self->{REMOTEINFO} = \%params;
    if (!defined $self->{REMOTEINFO}->{'method'}) {
      $self->{REMOTEINFO}->{'method'} = 'ssh';
    }
    if (!defined $self->{REMOTEINFO}->{'username'}) {
      $self->{REMOTEINFO}->{'username'} = $pwd[0] ||
                                          $ENV{LOGNAME} || $ENV{USERNAME};
    }
    if (!defined $self->{REMOTEINFO}->{'shell'}) {
      $self->{REMOTEINFO}->{'shell'} = basename($pwd[8]);
    }
  }
}

###############################################################################

# Spawn the process and continue;

sub Normalize_Executable_Name
{
    my $executable = shift;

    my $basename = basename ($executable);
    my $dirname = dirname ($executable). '/';

    $executable = $dirname.$PerlACE::Process::ExeSubDir.$basename;

    return $executable;
}

sub Spawn ()
{
    my $self = shift;

    if ($self->{RUNNING} == 1) {
        print STDERR "ERROR: Cannot Spawn: <", $self->Executable (),
                     "> already running\n";
        return -1;
    }

    if (!defined $self->{EXECUTABLE}) {
        print STDERR "ERROR: Cannot Spawn: No executable specified\n";
        return -1;
    }

    if ($self->{IGNOREEXESUBDIR} == 0) {
        if (!defined $self->{REMOTEINFO} && !-f $self->Executable ()) {
            print STDERR "ERROR: Cannot Spawn: <", $self->Executable (),
                         "> not found\n";
            return -1;
        }
    }

    my $cmdline = "";
    my $executable = "";

    if (defined $self->{VALGRIND_CMD}) {
        my $orig_cmdline = $self->CommandLine();
        $executable = $self->{VALGRIND_CMD};
        my $basename = basename ($self->{EXECUTABLE});

        $cmdline = "$executable $orig_cmdline";
    }
    elsif (defined $ENV{'ACE_TEST_WINDOW'}) {
      $cmdline = $ENV{'ACE_TEST_WINDOW'} . ' ' . $self->CommandLine();
    }
    else {
        $executable = $self->Executable();
        $cmdline = $self->CommandLine();
    }

    FORK:
    {
        if ($self->{PROCESS} = fork) {
            #parent here
            bless $self;
        }
        elsif (defined $self->{PROCESS}) {
            #child here
            if (defined $ENV{'ACE_TEST_VERBOSE'}) {
              print "$cmdline\n";
            }
            exec $cmdline;
            die "ERROR: exec failed for <" . $cmdline . ">";
        }
        elsif ($! =~ /No more process/) {
            #EAGAIN, supposedly recoverable fork error
            sleep 5;
            redo FORK;
        }
        else {
            # weird fork error
            print STDERR "ERROR: Can't fork <" . $cmdline . ">: $!\n";
        }
    }
    $self->{RUNNING} = 1;
    return 0;
}

sub WaitKill ($)
{
    my $self = shift;
    my $timeout = shift;

    my $status = $self->TimedWait ($timeout);

    if ($status == -1) {
        print STDERR "ERROR: $self->{EXECUTABLE} timedout\n";
        $self->Kill ();
    }

    $self->{RUNNING} = 0;

    return $status;
}


# Do a Spawn and immediately WaitKill

sub SpawnWaitKill ($)
{
    my $self = shift;
    my $timeout = shift;

    if ($self->Spawn () == -1) {
        return -1;
    }

    return $self->WaitKill ($timeout);
}

sub TerminateWaitKill ($)
{
    my $self = shift;
    my $timeout = shift;

    if ($self->{RUNNING}) {
        print STDERR "INFO: $self->{EXECUTABLE} being killed.\n";
        kill ('TERM', $self->{PROCESS});
    }

    return $self->WaitKill ($timeout);
}

# really only for internal use
sub check_return_value ($)
{
    my $self = shift;
    my $rc = shift;

    # NSK OSS has a 32-bit waitpid() status
    my $is_NSK = ($^O eq "nonstop_kernel");
    my $CC_MASK = $is_NSK ? 0xffff00 : 0xff00;

    # Exit code processing
    if ($rc == 0) {
        return 0;
    }
    elsif ($rc == $CC_MASK) {
        print STDERR "ERROR: <", $self->{EXECUTABLE},
                     "> failed: $!\n";
        return ($rc >> 8);
    }
    elsif (($rc & 0xff) == 0) {
        $rc >>= 8;
        return $rc;
    }

    # Ignore NSK 16-bit completion code
    $rc &= 0xff if $is_NSK;

    # Remember Core dump flag
    my $dump = 0;

    if ($rc & 0x80) {
        $rc &= ~0x80;
        $dump = 1;
    }

    # check for ABRT, KILL or TERM
    if ($rc == 6 || $rc == 9 || $rc == 15) {
        return 0;
    }

    print STDERR "ERROR: <", $self->{EXECUTABLE},
                 "> exited with ";

    print STDERR "coredump from " if ($dump == 1);

    print STDERR "signal $rc : ", $signame[$rc], "\n";

    return 0;
}

sub Kill ($)
{
    my $self = shift;
    my $ignore_return_value = shift;

    if ($self->{RUNNING} && !defined $ENV{'ACE_TEST_WINDOW'}) {
        kill ('KILL', $self->{PROCESS});
        waitpid ($self->{PROCESS}, 0);
        if (! $ignore_return_value) {
            $self->check_return_value ($?);
        }
    }

    $self->{RUNNING} = 0;
}

# Wait until a process exits.
# return -1 if the process is still alive.
sub Wait ($)
{
    my $self = shift;
    my $timeout = shift;
    if (!defined $timeout || $timeout < 0) {
    waitpid ($self->{PROCESS}, 0);
    } else {
      return TimedWait($self, $timeout);
    }

}

sub TimedWait ($)
{
    my $self = shift;
    my $timeout = shift;

    $timeout *= $PerlACE::Process::WAIT_DELAY_FACTOR;

    while ($timeout-- != 0) {
        my $pid = waitpid ($self->{PROCESS}, &WNOHANG);
        if ($pid != 0 && $? != -1) {
            return $self->check_return_value ($?);
        }
        sleep 1;
    }

    return -1;
}

1;