--- deliantra/server/lib/cf.pm	2007/01/02 08:26:42	1.119
+++ deliantra/server/lib/cf.pm	2007/01/02 11:08:36	1.120
@@ -183,6 +183,70 @@
    JSON::Syck::Dump $_[0]
 }
 
+=item my $guard = cf::guard { BLOCK }
+
+Run the given callback when the guard object gets destroyed (useful for
+coroutine cancellations).
+
+You can call C<< ->cancel >> on the guard object to stop the block from
+being executed.
+
+=cut
+
+sub guard(&) {
+   bless \(my $cb = $_[0]), cf::guard::;
+}
+
+sub cf::guard::cancel {
+   ${$_[0]} = sub { };
+}
+
+sub cf::guard::DESTROY {
+   ${$_[0]}->();
+}
+
+=item cf::lock_wait $string
+
+Wait until the given lock is available. See cf::lock_acquire. 
+
+=item my $lock = cf::lock_acquire $string
+
+Wait until the given lock is available and then acquires it and returns
+a guard object. If the guard object gets destroyed (goes out of scope,
+for example when the coroutine gets canceled), the lock is automatically
+returned.
+
+Lock names should begin with a unique identifier (for example, find_map
+uses map_find and load_map uses map_load).
+
+=cut
+
+our %LOCK;
+
+sub lock_wait($) {
+   my ($key) = @_;
+
+   # wait for lock, if any
+   while ($LOCK{$key}) {
+      push @{ $LOCK{$key} }, $Coro::current;
+      Coro::schedule;
+   }
+}
+
+sub lock_acquire($) {
+   my ($key) = @_;
+
+   # wait, to be sure we are not locked
+   lock_wait $key;
+
+   $LOCK{$key} = [];
+
+   cf::guard {
+      # wake up all waiters, to be on the safe side
+      $_->ready for @{ delete $LOCK{$key} };
+   }
+}
+
 =item cf::sync_job { BLOCK }
 
 The design of crossfire+ requires that the main coro ($Coro::main) is
@@ -1120,7 +1184,11 @@
    $path = new cf::path $path, $origin && $origin->path;
    my $key = $path->as_string;
 
+   cf::lock_wait "map_find:$key";
+
    $cf::MAP{$key} || do {
+      my $guard = cf::lock_acquire "map_find:$key";
+
       # do it the slow way
       my $map = try_load_header $path->save_path;
 
@@ -1163,12 +1231,13 @@
 sub load {
    my ($self) = @_;
 
+   my $path = $self->{path};
+   my $guard = cf::lock_acquire "map_load:" . $path->as_string;
+
    return if $self->in_memory != cf::MAP_SWAPPED;
 
    $self->in_memory (cf::MAP_LOADING);
 
-   my $path = $self->{path};
-
    $self->alloc;
    $self->load_objects ($self->{load_path}, 1)
       or return;
@@ -1410,13 +1479,14 @@
 sub cf::object::player::enter_link {
    my ($self) = @_;
 
+   $self->deactivate_recursive;
+
    return if $self->map == $LINK_MAP;
 
-   $self->{_link_pos} = [$self->map->{path}, $self->x, $self->y]
+   $self->{_link_pos} ||= [$self->map->{path}, $self->x, $self->y]
       if $self->map;
 
    $self->enter_map ($LINK_MAP, 20, 20);
-   $self->deactivate_recursive;
 }
 
 sub cf::object::player::leave_link {
@@ -1449,6 +1519,34 @@
    $self->enter_map ($map, $x, $y);
 }
 
+cf::player->attach (
+   on_logout => sub {
+      my ($pl) = @_;
+
+      # abort map switching before logout
+      if ($pl->ob->{_link_pos}) {
+         cf::sync_job {
+            $pl->ob->leave_link
+         };
+      }
+   },
+   on_login => sub {
+      my ($pl) = @_;
+
+      # try to abort aborted map switching on player login :)
+      # should happen only on crashes
+      if ($pl->ob->{_link_pos}) {
+         $pl->ob->enter_link;
+         Coro::async {
+            # we need this sleep as the login has a concurrent enter_exit running
+            # and this sleep increases chances of the player not ending up in scorn
+            Coro::Timer::sleep 1;
+            $pl->ob->leave_link;
+         };
+      }
+   },
+);
+
 =item $player_object->goto_map ($path, $x, $y)
 
 =cut