update copyrights for 2021

[public-inbox.git] / lib / PublicInbox / Syscall.pm

diff --git a/lib/PublicInbox/Syscall.pm b/lib/PublicInbox/Syscall.pm
index e4f00a2a2f736a995072dbac0db320ea49cb925e..a1f532353eab391020be7a94710433839fc2d278 100644 (file)
--- a/lib/PublicInbox/Syscall.pm
+++ b/lib/PublicInbox/Syscall.pm
@@ -5,7 +5,7 @@
 # This license differs from the rest of public-inbox
 #
 # This module is Copyright (c) 2005 Six Apart, Ltd.
-# Copyright (C) 2019-2020 all contributors <meta@public-inbox.org>
+# Copyright (C) 2019-2021 all contributors <meta@public-inbox.org>
 #
 # All rights reserved.
 #
@@ -22,7 +22,7 @@ our @EXPORT_OK = qw(epoll_ctl epoll_create epoll_wait
                   EPOLLIN EPOLLOUT EPOLLET
                   EPOLL_CTL_ADD EPOLL_CTL_DEL EPOLL_CTL_MOD
                   EPOLLONESHOT EPOLLEXCLUSIVE
-                  signalfd $SFD_NONBLOCK);
+                  signalfd SFD_NONBLOCK);
 our %EXPORT_TAGS = (epoll => [qw(epoll_ctl epoll_create epoll_wait
                              EPOLLIN EPOLLOUT
                              EPOLL_CTL_ADD EPOLL_CTL_DEL EPOLL_CTL_MOD
@@ -67,7 +67,7 @@ our (
      );
 
 my $SFD_CLOEXEC = 02000000; # Perl does not expose O_CLOEXEC
-our $SFD_NONBLOCK = O_NONBLOCK;
+sub SFD_NONBLOCK () { O_NONBLOCK }
 our $no_deprecated = 0;
 
 if ($^O eq "linux") {
@@ -227,38 +227,46 @@ sub epoll_ctl_mod8 {
 our $epoll_wait_events;
 our $epoll_wait_size = 0;
 sub epoll_wait_mod4 {
-    # resize our static buffer if requested size is bigger than we've ever done
-    if ($_[1] > $epoll_wait_size) {
-        $epoll_wait_size = $_[1];
-        $epoll_wait_events = "\0" x 12 x $epoll_wait_size;
-    }
-    my $ct = syscall($SYS_epoll_wait, $_[0]+0, $epoll_wait_events, $_[1]+0, $_[2]+0);
-    for (0..$ct-1) {
-        @{$_[3]->[$_]}[1,0] = unpack("LL", substr($epoll_wait_events, 12*$_, 8));
-    }
-    return $ct;
+       my ($epfd, $maxevents, $timeout_msec, $events) = @_;
+       # resize our static buffer if maxevents bigger than we've ever done
+       if ($maxevents > $epoll_wait_size) {
+               $epoll_wait_size = $maxevents;
+               vec($epoll_wait_events, $maxevents * 12 * 8 - 1, 1) = 0;
+       }
+       @$events = ();
+       my $ct = syscall($SYS_epoll_wait, $epfd, $epoll_wait_events,
+                       $maxevents, $timeout_msec);
+       for (0..$ct - 1) {
+               # 12-byte struct epoll_event
+               # 4 bytes uint32_t events mask (skipped, useless to us)
+               # 8 bytes: epoll_data_t union (first 4 bytes are the fd)
+               # So we skip the first 4 bytes and take the middle 4:
+               $events->[$_] = unpack('L', substr($epoll_wait_events,
+                                                       12 * $_ + 4, 4));
+       }
 }
 
 sub epoll_wait_mod8 {
-    # resize our static buffer if requested size is bigger than we've ever done
-    if ($_[1] > $epoll_wait_size) {
-        $epoll_wait_size = $_[1];
-        $epoll_wait_events = "\0" x 16 x $epoll_wait_size;
-    }
-    my $ct;
-    if ($no_deprecated) {
-        $ct = syscall($SYS_epoll_wait, $_[0]+0, $epoll_wait_events, $_[1]+0, $_[2]+0, undef);
-    } else {
-        $ct = syscall($SYS_epoll_wait, $_[0]+0, $epoll_wait_events, $_[1]+0, $_[2]+0);
-    }
-    for (0..$ct-1) {
-        # 16 byte epoll_event structs, with format:
-        #    4 byte mask [idx 1]
-        #    4 byte padding (we put it into idx 2, useless)
-        #    8 byte data (first 4 bytes are fd, into idx 0)
-        @{$_[3]->[$_]}[1,2,0] = unpack("LLL", substr($epoll_wait_events, 16*$_, 12));
-    }
-    return $ct;
+       my ($epfd, $maxevents, $timeout_msec, $events) = @_;
+
+       # resize our static buffer if maxevents bigger than we've ever done
+       if ($maxevents > $epoll_wait_size) {
+               $epoll_wait_size = $maxevents;
+               vec($epoll_wait_events, $maxevents * 16 * 8 - 1, 1) = 0;
+       }
+       @$events = ();
+       my $ct = syscall($SYS_epoll_wait, $epfd, $epoll_wait_events,
+                       $maxevents, $timeout_msec,
+                       $no_deprecated ? undef : ());
+       for (0..$ct - 1) {
+               # 16-byte struct epoll_event
+               # 4 bytes uint32_t events mask (skipped, useless to us)
+               # 4 bytes padding (skipped, useless)
+               # 8 bytes epoll_data_t union (first 4 bytes are the fd)
+               # So skip the first 8 bytes, take 4, and ignore the last 4:
+               $events->[$_] = unpack('L', substr($epoll_wait_events,
+                                                       16 * $_ + 8, 4));
+       }
 }
 
 sub signalfd ($$$) {