--- Coro/Coro.pm	2001/07/21 18:21:45	1.20
+++ Coro/Coro.pm	2001/10/03 01:09:56	1.38
@@ -16,7 +16,7 @@
     # some more async code
  }
 
- yield;
+ cede;
 
 =head1 DESCRIPTION
 
@@ -26,25 +26,31 @@
 This module is still experimental, see the BUGS section below.
 
 In this module, coroutines are defined as "callchain + lexical variables
-+ @_ + $_ + $@ + $^W), that is, a coroutine has it's own callchain, it's
-own set of lexicals and it's own set of perl's most important global
-variables.
++ @_ + $_ + $@ + $^W + C stack), that is, a coroutine has it's own
+callchain, it's own set of lexicals and it's own set of perl's most
+important global variables.
 
 =cut
 
 package Coro;
 
+no warnings qw(uninitialized);
+
 use Coro::State;
 
 use base Exporter;
 
-$VERSION = 0.10;
+$VERSION = 0.51;
 
-@EXPORT = qw(async yield schedule terminate current);
-@EXPORT_OK = qw($current);
+@EXPORT = qw(async cede schedule terminate current);
+%EXPORT_TAGS = (
+      prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
+);
+@EXPORT_OK = @{$EXPORT_TAGS{prio}};
 
 {
    my @async;
+   my $init;
 
    # this way of handling attributes simply is NOT scalable ;()
    sub import {
@@ -56,6 +62,13 @@
          for (@_) {
             if ($_ eq "Coro") {
                push @async, $ref;
+               unless ($init++) {
+                  eval q{
+                     sub INIT {
+                        &async(pop @async) while @async;
+                     }
+                  };
+               }
             } else {
                push @attrs, $_;
             }
@@ -64,9 +77,6 @@
       };
    }
 
-   sub INIT {
-      &async(pop @async) while @async;
-   }
 }
 
 =item $main
@@ -105,8 +115,21 @@
    exit(51);
 };
 
-# we really need priorities...
-my @ready; # the ready queue. hehe, rather broken ;)
+# this coroutine is necessary because a coroutine
+# cannot destroy itself.
+my @destroy;
+my $manager;
+$manager = new Coro sub {
+   while() {
+      # by overwriting the state object with the manager we destroy it
+      # while still being able to schedule this coroutine (in case it has
+      # been readied multiple times. this is harmless since the manager
+      # can be called as many times as neccessary and will always
+      # remove itself from the runqueue
+      (pop @destroy)->{_coro_state} = $manager->{_coro_state} while @destroy;
+      &schedule;
+   }
+};
 
 # static methods. not really.
 
@@ -134,6 +157,7 @@
 
 sub async(&@) {
    my $pid = new Coro @_;
+   $manager->ready; # this ensures that the stack is cloned from the manager
    $pid->ready;
    $pid;
 }
@@ -146,26 +170,14 @@
 
 =cut
 
-my $prev;
+=item cede
 
-sub schedule {
-   # should be done using priorities :(
-   ($prev, $current) = ($current, shift @ready || $idle);
-   Coro::State::transfer($prev, $current);
-}
-
-=item yield
-
-Yield to other processes. This function puts the current process into the
-ready queue and calls C<schedule>.
+"Cede" to other processes. This function puts the current process into the
+ready queue and calls C<schedule>, which has the effect of giving up the
+current "timeslice" to other coroutines of the same or higher priority.
 
 =cut
 
-sub yield {
-   $current->ready;
-   &schedule;
-}
-
 =item terminate
 
 Terminates the current process.
@@ -175,8 +187,9 @@
 =cut
 
 sub terminate {
-   $current->{_results} = [@_];
+   $current->cancel;
    &schedule;
+   die; # NORETURN
 }
 
 =back
@@ -217,8 +230,56 @@
 
 =cut
 
-sub ready {
-   push @ready, $_[0];
+=item $process->cancel
+
+Like C<terminate>, but terminates the specified process instead.
+
+=cut
+
+sub cancel {
+   push @destroy, $_[0];
+   $manager->ready;
+   &schedule if $current == $_[0];
+}
+
+=item $oldprio = $process->prio($newprio)
+
+Sets the priority of the process. Higher priority processes get run before
+lower priority processes. Priorities are smalled signed integer (currently
+-4 .. +3), that you can refer to using PRIO_xxx constants (use the import
+tag :prio to get then):
+
+   PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
+       3    >     1     >      0      >    -1    >    -3     >    -4
+
+   # set priority to HIGH
+   current->prio(PRIO_HIGH);
+
+The idle coroutine ($Coro::idle) always has a lower priority than any
+existing coroutine.
+
+Changing the priority of the current process will take effect immediately,
+but changing the priority of processes in the ready queue (but not
+running) will only take effect after the next schedule (of that
+process). This is a bug that will be fixed in some future version.
+
+=cut
+
+sub prio {
+   my $old = $_[0]{prio};
+   $_[0]{prio} = $_[1] if @_ > 1;
+   $old;
+}
+
+=item $newprio = $process->nice($change)
+
+Similar to C<prio>, but subtract the given value from the priority (i.e.
+higher values mean lower priority, just as in unix).
+
+=cut
+
+sub nice {
+   $_[0]{prio} -= $_[1];
 }
 
 =back
@@ -229,14 +290,8 @@
 
 =head1 BUGS/LIMITATIONS
 
- - could be faster, especially when the core would introduce special
-   support for coroutines (like it does for threads).
- - there is still a memleak on coroutine termination that I could not
-   identify. Could be as small as a single SV.
- - this module is not well-tested.
- - if variables or arguments "disappear" (become undef) or become
-   corrupted please contact the author so he cen iron out the
-   remaining bugs.
+ - you must make very sure that no coro is still active on global destruction.
+   very bad things might happen otherwise (usually segfaults).
  - this module is not thread-safe. You must only ever use this module from
    the same thread (this requirement might be loosened in the future to
    allow per-thread schedulers, but Coro::State does not yet allow this).
@@ -244,7 +299,8 @@
 =head1 SEE ALSO
 
 L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>,
-L<Coro::Signal>, L<Coro::State>, L<Coro::Event>.
+L<Coro::Signal>, L<Coro::State>, L<Coro::Event>, L<Coro::RWLock>,
+L<Coro::Handle>, L<Coro::Socket>.
 
 =head1 AUTHOR