From 1a3e2ef16d3d6915a126a3fbb3eb527f3b9d8a3f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Fri, 16 Oct 2015 17:20:04 +0100
Subject: [PATCH 1/2] Fix assertion when calling IO::Poll::_poll() with an
 empty fd array
MIME-Version: 1.0
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  perl: IO.xs:322: XS_IO__Poll__poll: Assertion
  `PL_valid_types_PVX[((svtype)((_svpvx)->sv_flags & 0xff)) & 0xf]'
  failed.

This is because NEWSV(…, 0) returns undef, with a grabage pointer in
the PV slot.  This doesn't seem to matter in practice, since nothing
actually dereferences the pointer when nfds is zero, but to be safe we
should pass in _some_ valid pointer, so just use the SV* itself;
---
 dist/IO/IO.pm | 2 +-
 dist/IO/IO.xs | 5 ++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/dist/IO/IO.pm b/dist/IO/IO.pm
index 2762958..de3e991 100644
--- a/dist/IO/IO.pm
+++ b/dist/IO/IO.pm
@@ -7,7 +7,7 @@ package IO;
 use strict;
 use warnings;
 
-our $VERSION = "1.35";
+our $VERSION = "1.36";
 XSLoader::load 'IO', $VERSION;
 
 sub import {
diff --git a/dist/IO/IO.xs b/dist/IO/IO.xs
index 1f546b9..fe749a6 100644
--- a/dist/IO/IO.xs
+++ b/dist/IO/IO.xs
@@ -319,7 +319,10 @@ _poll(timeout,...)
 #ifdef HAS_POLL
     const int nfd = (items - 1) / 2;
     SV *tmpsv = NEWSV(999,nfd * sizeof(struct pollfd));
-    struct pollfd *fds = (struct pollfd *)SvPVX(tmpsv);
+    /* We should pass _some_ valid pointer even if nfd is zero, but it
+     * doesn't matter what it is, since we're telling it to not check any fds.
+     */
+    struct pollfd *fds = nfd ? (struct pollfd *)SvPVX(tmpsv) : (struct pollfd *)tmpsv;
     int i,j,ret;
     for(i=1, j=0  ; j < nfd ; j++) {
 	fds[j].fd = SvIV(ST(i));
-- 
2.6.1

From 8255ee3a96bbc4b3f237eecabefa546c82b8520d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dagfinn=20Ilmari=20Manns=C3=A5ker?= <ilmari@ilmari.org>
Date: Fri, 16 Oct 2015 17:23:40 +0100
Subject: [PATCH 2/2] Make IO::Poll->poll call _poll even with an empty fd
 array

Now that _poll() properly handles an empty array, this fixes
[rt.cpan.org #25049].  The commit referenced in that ticket never made
it to CPAN nor blead.
---
 dist/IO/lib/IO/Poll.pm |  4 ++--
 dist/IO/t/io_poll.t    | 11 ++++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/dist/IO/lib/IO/Poll.pm b/dist/IO/lib/IO/Poll.pm
index 47f1a13..a02dc3d 100644
--- a/dist/IO/lib/IO/Poll.pm
+++ b/dist/IO/lib/IO/Poll.pm
@@ -13,7 +13,7 @@ package IO::Poll;
 our(@ISA, @EXPORT_OK, @EXPORT, $VERSION);
 
 @ISA = qw(Exporter);
-$VERSION = "0.09";
+$VERSION = "0.10";
 
 @EXPORT = qw( POLLIN
 	      POLLOUT
@@ -83,7 +83,7 @@ sub poll {
 	push(@poll,$fd => $mask);
     }
 
-    my $ret = @poll ? _poll(defined($timeout) ? $timeout * 1000 : -1,@poll) : 0;
+    my $ret = _poll(defined($timeout) ? $timeout * 1000 : -1,@poll);
 
     return $ret
 	unless $ret > 0;
diff --git a/dist/IO/t/io_poll.t b/dist/IO/t/io_poll.t
index 364d346..c58467c 100644
--- a/dist/IO/t/io_poll.t
+++ b/dist/IO/t/io_poll.t
@@ -8,7 +8,7 @@
 select(STDERR); $| = 1;
 select(STDOUT); $| = 1;
 
-print "1..10\n";
+print "1..12\n";
 
 use IO::Handle;
 use IO::Poll qw(/POLL/);
@@ -81,3 +81,12 @@
 print "not "
     if $poll->poll(0.1);
 print "ok 10\n";
+
+my $wait = IO::Poll->new;
+my $now = time;
+my $zero = $wait->poll(2);
+my $diff = time - $now;
+print "not " if !defined($zero) or $zero;
+print "ok 11\n";
+print "not " unless $diff >= 2;
+print "ok 12\n";
-- 
2.6.1