Re: Win32::MMF AP 5.8.7 : Access violation in MMF.dll

[Roger]

Can you show us a little bit of code?

[spaetzle]

The code: It crashes in GlxShMem->put and it has nothing to do with the fact if the child is in zombie state or not. This code works perfect with linux and IPC::Shareable.

I've tried to compress ist a little bit ;-)


sub main {
    my $self = shift;
    my $paddr;
    my $waitedpid = 0;
    sub spawn;
    sub logmsg;
    
    $server = GlxInetServer->new($port{"servd"},1,"servd");

    for ( $waitedpid = 0; ($paddr = $server->accept()) || $waitedpid; 
+$waitedpid = 0, $server->close()) {
        next if $waitedpid and not $paddr;

        spawn sub{

            $client_modd = GlxInetClient->new($port{"modd"},1,"servd")
+;
            $server->write("440 Servd ready for commands");
            my $in=$server->read();
            unless (defined $in) { $self->unexpected; last };

            SWITCH: {
                ($in =~ /^status/) && do {
                    $server->write($ob_modds[0]->status);
                    $server->write("OK connecting statd");
                    last SWITCH;
                };
                
                ($in =~ /^something/ && do {
                    ### snip
                    $client_modd->write($in);
                    ### snip
                    $client_modd->close();
                    last SWITCH;
                };
                
                ($in =~ /^bye$/) && do {
                    $server->write("OK");
                    last SWITCH;
                };

                $server->write("450 No such command");
                $client_modd->close();
            } # SWITCH
        }# spawn
    }# for

    sub spawn {
        my $coderef = shift;
        die unless (@_ == 0 && $coderef && ref($coderef) eq 'CODE');
        my $pid;
        if (!defined($pid = fork)){
            logmsg "cannot fork: $!";
            return;
        } elsif ($pid) {
            logmsg "[$pid] listening for ".$server->get_iname()." [", 
+inet_ntoa($server->get_iaddr()),"]";
            return;
        }
        exit &$coderef();
    }
} #main

and the SysV shm replacement

# GlxShMem
# this is an replacement for an old SysV IPC shm package ported to Win

package GlxShMem;
use Win32::MMF::Shareable;

sub alloc {
    my $class = shift;
    my $value = @_ ? shift : '';

    my $self = bless {
        OWNER => $$,
    } => $class;
    
    my %options = (
        create => 1,
        exclusive => 1,
        mode => 0666,
        destroy => 1,
        reuse => 1,
        autolock => 1,
    );
    
    $self->{SHMKEY} = $self;
    $self->{SHMKEY} =~ s/(\(.+\))/$1/;
    $self->{SHMKEY} = $1;
    $self->{SHMKEY} =~ s/\(|\)//g;
    $self->{SHMKEY} =~ s/0x//;
    
    while ($self->{SHMKEY} =~ s/\D/$1/) {
        my $h = ord($1);
        $self->{SHMKEY} =~ s/\D/$h/;    
    }
    
    tie $self->{DATA}, 'Win32::MMF::Shareable', $self->{SHMKEY}, {%opt
+ions} or die 'GlxShMem->alloc() : Tie failed\n';
    $self->{DATA} = $value;
    
    return $self;
}

sub get {
    my $self = shift;
    return $self->{DATA};
}

sub put {
    my $self = shift;
    if ($debug) {
       my %options = (
          create => 0,
          exclusive => 0,
          mode => 0666,
          destroy => 1,
          reuse => 1,
          autolock => 1,
     );
    my $ns=tie $self->{DATA}, 'Win32::MMF::Shareable', self->{SHMKEY},
+ {%options} or die 'debug : Tie failed\n';
      $ns->debug();
    }       
    $self->{DATA} = shift;
}

sub DESTROY {
    my $self = shift;
    return unless $self->{OWNER} == $$;
    (tied $self->{DATA})->deletevar($self->{DATA});
}

1;

### end GlxShMem

and the example for shm use

package GlxModd;

use strict;
use warnings;
use GlxGlobalVars;
use GlxInetServer;
use GlxShMem;

sub new {

    my $class = shift;
    my $id = shift;
    my $device = shift;
    my $port = shift;
    my $logfile = shift;
    my $debug = shift || 0;
    my $string = shift || '';

    my $self = bless {
        ID => GlxShMem->alloc($id),
        DEVICE => GlxShMem->alloc($device),
        PORT => GlxShMem->alloc($port),
        LOGFILE => GlxShMem->alloc($logfile),
        DEBUG => GlxShMem->alloc($debug),
        STRING => GlxShMem->alloc($string),
        
        STAT => GlxShMem->alloc(0),
    #    MODEM => GlxShMem->alloc(0),
    #    GSM => GlxShMem->alloc(0),
    } => $class;
    
    $self->{STAT}->put(0);
    return $self;
}

sub status {
    my $self=shift;
    return $self->{STAT}->get;
}

sub main {
    my $self = shift;

    my $server = GlxInetServer->new($self->{PORT}->get, $self->{DEBUG}
+->get, $self->{STRING}->get);

    for ( ; $server->accept() ; $server->close()) {
        my $in = $server->read();

        SWITCH: {

            ($in =~ /^something/) && do {
                $server->write("OK");
                
                # FAKE
                my $z=0;
                while (1) {
                $self->{STAT}->put(1);
                    $z++;
                    $server->write($z);
                    sleep 1;
                    last if ($z==20);
                }
                $self->{STAT}->put(0);
            };
        };
    }
} # main

1;

[Roger]

Hi spaetzle I am very busy this morning so I can not take a closer look at the problem, but I will definitely get back to later you on this.

[spaetzle]

Hi Roger,
that doesn't matter. I'm working around the problem yet but I'm really interested in to know what you think about.
Spaetzle