Async-Interrupt-1.25/0000755000000000000000000000000013457035364013220 5ustar rootrootAsync-Interrupt-1.25/t/0000755000000000000000000000000013457035364013463 5ustar rootrootAsync-Interrupt-1.25/t/06_epipe.t0000644000000000000000000000110211373362762015251 0ustar rootroot#! perl no warnings; print "1..6\n"; $|=1; use Async::Interrupt; my $ep = new Async::Interrupt::EventPipe; my $fd = $ep->fileno; print "ok 1\n"; my ($vr, $vR); vec ($vr, $fd, 1) = 1; my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 2 # $n\n"; $ep->signal; my $n = select $vR=$vr, undef, undef, 0; print $n == 1 ? "" : "not ", "ok 3 # $n\n"; $ep->drain; my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 4 # $n\n"; print "ok 5 # ", join " ", $ep->signal_func, "\n"; print "ok 6 # ", join " ", $ep->drain_func, "\n"; Async-Interrupt-1.25/t/00_load.t0000644000000000000000000000017611223114451015052 0ustar rootrootBEGIN { $| = 1; print "1..1\n"; } END {print "not ok 1\n" unless $loaded;} use Async::Interrupt; $loaded = 1; print "ok 1\n"; Async-Interrupt-1.25/t/04_apipe.t0000644000000000000000000000200011227750114015227 0ustar rootroot#! perl no warnings; print "1..14\n"; $|=1; use Async::Interrupt; my $ai = new Async::Interrupt cb => sub { print "ok $_[0]\n" }; my $fd = $ai->pipe_fileno; print "ok 1\n"; $ai->signal (2); print "ok 3\n"; my ($vr, $vR); vec ($vr, $ai->pipe_fileno, 1) = 1; my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 4 # $n\n"; $ai->block; $ai->signal (7); print "ok 5\n"; my $n = select $vR=$vr, undef, undef, 0; print $n == 1 ? "" : "not ", "ok 6 # $n\n"; $ai->unblock; my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 8 # $n\n"; $ai->signal (9); my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 10 # $n\n"; $ai->pipe_disable; $ai->scope_block; $ai->signal (14); my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 11 # $n\n"; $ai->post_fork; print $fd == $ai->pipe_fileno ? "" : "not ", "ok 12\n"; $ai->post_fork; print $fd == $ai->pipe_fileno ? "" : "not ", "ok 13\n"; undef $ai; # will cause signal to be sent Async-Interrupt-1.25/t/01_basic.t0000644000000000000000000000106211223156162015215 0ustar rootrootprint "1..12\n"; $|=1; use Async::Interrupt; my $ai = new Async::Interrupt cb => sub { print "ok $_[0]\n" }; my $ai2 = new Async::Interrupt; print $$ai ? "" : "not ", "ok 1 # $$ai\n"; my ($a, $b) = $ai->signal_func; print $a ? "" : "not ", "ok 2 # $a\n"; print $b ? "" : "not ", "ok 3 # $b\n"; $ai->signal (4); my $ai3 = new Async::Interrupt; print "ok 5\n"; $ai->block; $ai->signal (7); print "ok 6\n"; $ai->unblock; print "ok 8\n"; undef $ai2; print "ok 9\n"; { $ai->scope_block; $ai->signal (11); print "ok 10\n"; } print "ok 12\n"; Async-Interrupt-1.25/t/05_var.t0000644000000000000000000000063411227754440014743 0ustar rootrootprint "1..7\n"; $|=1; use Async::Interrupt; my $var; my $ai = new Async::Interrupt var => \$var, cb => sub { print $var ? "not " : "", "ok $_[0]\n" }; print $$ai ? "" : "not ", "ok 1 # $$ai\n"; print $ai->c_var ? "" : "not ", "ok 2\n"; $ai->signal (3); print $var == 0 ? "" : "not ", "ok 4\n"; $ai->block; $ai->signal (7); print "ok 5\n"; print $var == 7 ? "" : "not ", "ok 6\n"; $ai->unblock; Async-Interrupt-1.25/t/03_signal.t0000644000000000000000000000076711233451105015422 0ustar rootrootunless (exists $SIG{USR1}) { print "1..0 # SKIP no SIGUSR1 - broken platform, skipping tests\n"; exit; } print "1..9\n"; $|=1; use Async::Interrupt; my $three = 3; my $ai = new Async::Interrupt cb => sub { print "ok ", $three++, "\n" }, signal => "CHLD"; print "ok 1\n"; { $ai->scope_block; $ai->scope_block; kill CHLD => $$; print "ok 2\n"; } kill CHLD, $$; $ai->signal_hysteresis (1); kill CHLD, $$; kill CHLD, $$; kill CHLD, $$; kill CHLD, $$; print "ok 9\n"; Async-Interrupt-1.25/t/02_pipe.t0000644000000000000000000000223611226205764015104 0ustar rootroot#! perl no warnings; use Socket; my ($pr, $pw); unless (socketpair $pr, $pw, Socket::AF_UNIX (), Socket::SOCK_STREAM (), 0) { print "1..0 # SKIP socketpair failed - broken platform, skipping tests\n"; exit; } print "1..12\n"; $|=1; use Async::Interrupt; # we ignore the requirement to put handles into nonblocking mode # IN THIS TEST only. never do that in real life. my $ai = new Async::Interrupt pipe => [$pr, $pw], cb => sub { print "ok $_[0]\n" }; print "ok 1\n"; $ai->signal (2); print "ok 3\n"; my ($vr, $vR); vec ($vr, fileno $pr, 1) = 1; my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 4 # $n\n"; $ai->block; $ai->signal (7); print "ok 5\n"; my $n = select $vR=$vr, undef, undef, 0; print $n == 1 ? "" : "not ", "ok 6 # $n\n"; $ai->unblock; my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 8 # $n\n"; $ai->signal (9); my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 10 # $n\n"; $ai->pipe_disable; $ai->scope_block; $ai->signal (12); my $n = select $vR=$vr, undef, undef, 0; print $n == 0 ? "" : "not ", "ok 11 # $n\n"; undef $ai; # will cause signal to be sent Async-Interrupt-1.25/schmorp.h0000644000000000000000000002440613411412371015035 0ustar rootroot#ifndef SCHMORP_PERL_H_ #define SCHMORP_PERL_H_ /* WARNING * This header file is a shared resource between many modules. * perl header files MUST already be included. */ #include #include #if defined(WIN32 ) || defined(_MINIX) # define SCHMORP_H_PREFER_SELECT 1 #endif #if !SCHMORP_H_PREFER_SELECT # include #endif /* useful stuff, used by schmorp mostly */ #include "patchlevel.h" #define PERL_VERSION_ATLEAST(a,b,c) \ (PERL_REVISION > (a) \ || (PERL_REVISION == (a) \ && (PERL_VERSION > (b) \ || (PERL_VERSION == (b) && PERL_SUBVERSION >= (c))))) #ifndef PERL_MAGIC_ext # define PERL_MAGIC_ext '~' #endif #if !PERL_VERSION_ATLEAST (5,6,0) # ifndef PL_ppaddr # define PL_ppaddr ppaddr # endif # ifndef call_sv # define call_sv perl_call_sv # endif # ifndef get_sv # define get_sv perl_get_sv # endif # ifndef get_cv # define get_cv perl_get_cv # endif # ifndef IS_PADGV # define IS_PADGV(v) 0 # endif # ifndef IS_PADCONST # define IS_PADCONST(v) 0 # endif #endif /* use NV for 32 bit perls as it allows larger offsets */ #if IVSIZE >= 8 typedef IV VAL64; # define SvVAL64(sv) SvIV (sv) # define newSVval64(i64) newSViv (i64) #else typedef NV VAL64; # define SvVAL64(sv) SvNV (sv) # define newSVval64(i64) newSVnv (i64) #endif /* typemap for the above */ /* VAL64 T_VAL64 INPUT T_VAL64 $var = ($type)SvVAL64 ($arg); OUTPUT T_VAL64 $arg = newSVval64 ($var); */ /* 5.11 */ #ifndef CxHASARGS # define CxHASARGS(cx) (cx)->blk_sub.hasargs #endif /* 5.10.0 */ #ifndef SvREFCNT_inc_NN # define SvREFCNT_inc_NN(sv) SvREFCNT_inc (sv) #endif /* 5.8.8 */ #ifndef GV_NOTQUAL # define GV_NOTQUAL 0 #endif #ifndef newSV # define newSV(l) NEWSV(0,l) #endif #ifndef CvISXSUB_on # define CvISXSUB_on(cv) (void)cv #endif #ifndef CvISXSUB # define CvISXSUB(cv) (CvXSUB (cv) ? TRUE : FALSE) #endif #ifndef Newx # define Newx(ptr,nitems,type) New (0,ptr,nitems,type) #endif /* 5.8.7 */ #ifndef SvRV_set # define SvRV_set(s,v) SvRV(s) = (v) #endif static int s_signum (SV *sig) { #ifndef SIG_SIZE /* kudos to Slaven Rezic for the idea */ static char sig_size [] = { SIG_NUM }; # define SIG_SIZE (sizeof (sig_size) + 1) #endif dTHX; int signum; SvGETMAGIC (sig); for (signum = 1; signum < SIG_SIZE; ++signum) if (strEQ (SvPV_nolen (sig), PL_sig_name [signum])) return signum; signum = SvIV (sig); if (signum > 0 && signum < SIG_SIZE) return signum; return -1; } static int s_signum_croak (SV *sig) { int signum = s_signum (sig); if (signum < 0) { dTHX; croak ("%s: invalid signal name or number", SvPV_nolen (sig)); } return signum; } static int s_fileno (SV *fh, int wr) { dTHX; SvGETMAGIC (fh); if (SvROK (fh)) { fh = SvRV (fh); SvGETMAGIC (fh); } if (SvTYPE (fh) == SVt_PVGV) return PerlIO_fileno (wr ? IoOFP (sv_2io (fh)) : IoIFP (sv_2io (fh))); if (SvOK (fh) && (SvIV (fh) >= 0) && (SvIV (fh) < 0x7fffffffL)) return SvIV (fh); return -1; } static int s_fileno_croak (SV *fh, int wr) { int fd = s_fileno (fh, wr); if (fd < 0) { dTHX; croak ("%s: illegal fh argument, either not an OS file or read/write mode mismatch", SvPV_nolen (fh)); } return fd; } static SV * s_get_cv (SV *cb_sv) { dTHX; HV *st; GV *gvp; return (SV *)sv_2cv (cb_sv, &st, &gvp, 0); } static SV * s_get_cv_croak (SV *cb_sv) { SV *cv = s_get_cv (cb_sv); if (!cv) { dTHX; croak ("%s: callback must be a CODE reference or another callable object", SvPV_nolen (cb_sv)); } return cv; } /*****************************************************************************/ /* gensub: simple closure generation utility */ #define S_GENSUB_ARG CvXSUBANY (cv).any_ptr /* create a closure from XS, returns a code reference */ /* the arg can be accessed via GENSUB_ARG from the callback */ /* the callback must use dXSARGS/XSRETURN */ static SV * s_gensub (pTHX_ void (*xsub)(pTHX_ CV *), void *arg) { CV *cv = (CV *)newSV (0); sv_upgrade ((SV *)cv, SVt_PVCV); CvANON_on (cv); CvISXSUB_on (cv); CvXSUB (cv) = xsub; S_GENSUB_ARG = arg; return newRV_noinc ((SV *)cv); } /*****************************************************************************/ /* portable pipe/socketpair */ #if defined(USE_SOCKETS_AS_HANDLES) || PERL_VERSION_ATLEAST(5,18,0) # define S_TO_HANDLE(x) ((HANDLE)win32_get_osfhandle (x)) #else # define S_TO_HANDLE(x) ((HANDLE)x) #endif #ifdef _WIN32 /* taken almost verbatim from libev's ev_win32.c */ /* oh, the humanity! */ static int s_pipe (int filedes [2]) { dTHX; struct sockaddr_in addr = { 0 }; int addr_size = sizeof (addr); struct sockaddr_in adr2; int adr2_size = sizeof (adr2); SOCKET listener; SOCKET sock [2] = { -1, -1 }; if ((listener = socket (AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) return -1; addr.sin_family = AF_INET; addr.sin_addr.s_addr = htonl (INADDR_LOOPBACK); addr.sin_port = 0; if (bind (listener, (struct sockaddr *)&addr, addr_size)) goto fail; if (getsockname (listener, (struct sockaddr *)&addr, &addr_size)) goto fail; if (listen (listener, 1)) goto fail; if ((sock [0] = socket (AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) goto fail; if (connect (sock [0], (struct sockaddr *)&addr, addr_size)) goto fail; if ((sock [1] = accept (listener, 0, 0)) < 0) goto fail; /* windows vista returns fantasy port numbers for getpeername. * example for two interconnected tcp sockets: * * (Socket::unpack_sockaddr_in getsockname $sock0)[0] == 53364 * (Socket::unpack_sockaddr_in getpeername $sock0)[0] == 53363 * (Socket::unpack_sockaddr_in getsockname $sock1)[0] == 53363 * (Socket::unpack_sockaddr_in getpeername $sock1)[0] == 53365 * * wow! tridirectional sockets! * * this way of checking ports seems to work: */ if (getpeername (sock [0], (struct sockaddr *)&addr, &addr_size)) goto fail; if (getsockname (sock [1], (struct sockaddr *)&adr2, &adr2_size)) goto fail; errno = WSAEINVAL; if (addr_size != adr2_size || addr.sin_addr.s_addr != adr2.sin_addr.s_addr /* just to be sure, I mean, it's windows */ || addr.sin_port != adr2.sin_port) goto fail; closesocket (listener); #if defined(USE_SOCKETS_AS_HANDLES) || PERL_VERSION_ATLEAST(5,18,0) /* when select isn't winsocket, we also expect socket, connect, accept etc. * to work on fds */ filedes [0] = sock [0]; filedes [1] = sock [1]; #else filedes [0] = _open_osfhandle (sock [0], 0); filedes [1] = _open_osfhandle (sock [1], 0); #endif return 0; fail: closesocket (listener); if (sock [0] != INVALID_SOCKET) closesocket (sock [0]); if (sock [1] != INVALID_SOCKET) closesocket (sock [1]); return -1; } #define s_socketpair(domain,type,protocol,filedes) s_pipe (filedes) static int s_fd_blocking (int fd, int blocking) { u_long nonblocking = !blocking; return ioctlsocket ((SOCKET)S_TO_HANDLE (fd), FIONBIO, &nonblocking); } #define s_fd_prepare(fd) s_fd_blocking (fd, 0) #else #define s_socketpair(domain,type,protocol,filedes) socketpair (domain, type, protocol, filedes) #define s_pipe(filedes) pipe (filedes) static int s_fd_blocking (int fd, int blocking) { return fcntl (fd, F_SETFL, blocking ? 0 : O_NONBLOCK); } static int s_fd_prepare (int fd) { return s_fd_blocking (fd, 0) || fcntl (fd, F_SETFD, FD_CLOEXEC); } #endif #if HAVE_EVENTFD # include #else # if __linux && (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ >= 7)) # define SCHMORP_H_HAVE_EVENTFD 1 /* our minimum requirement is glibc 2.7 which has the stub, but not the header */ # include # ifdef __cplusplus extern "C" { # endif int eventfd (unsigned int initval, int flags); # ifdef __cplusplus } # endif # else # define eventfd(initval,flags) -1 # endif #endif typedef struct { int fd[2]; /* read, write fd, might be equal */ int len; /* write length (1 pipe/socket, 8 eventfd) */ } s_epipe; static int s_epipe_new (s_epipe *epp) { s_epipe ep; ep.fd [0] = ep.fd [1] = eventfd (0, 0); if (ep.fd [0] >= 0) { s_fd_prepare (ep.fd [0]); ep.len = 8; } else { if (s_pipe (ep.fd)) return -1; if (s_fd_prepare (ep.fd [0]) || s_fd_prepare (ep.fd [1])) { dTHX; close (ep.fd [0]); close (ep.fd [1]); return -1; } ep.len = 1; } *epp = ep; return 0; } static void s_epipe_destroy (s_epipe *epp) { dTHX; close (epp->fd [0]); if (epp->fd [1] != epp->fd [0]) close (epp->fd [1]); epp->len = 0; } static void s_epipe_signal (s_epipe *epp) { #ifdef _WIN32 /* perl overrides send with a function that crashes in other threads. * unfortunately, it overrides it with an argument-less macro, so * there is no way to force usage of the real send function. * incompetent windows programmers - is this redundant? */ DWORD dummy; WriteFile (S_TO_HANDLE (epp->fd [1]), (LPCVOID)&dummy, 1, &dummy, 0); #else static uint64_t counter = 1; /* some modules accept fd's from outside, support eventfd here */ if (write (epp->fd [1], &counter, epp->len) < 0 && errno == EINVAL && epp->len != 8) write (epp->fd [1], &counter, (epp->len = 8)); #endif } static void s_epipe_drain (s_epipe *epp) { dTHX; char buf [9]; #ifdef _WIN32 recv (epp->fd [0], buf, sizeof (buf), 0); #else read (epp->fd [0], buf, sizeof (buf)); #endif } /* like new, but dups over old */ static int s_epipe_renew (s_epipe *epp) { dTHX; s_epipe epn; if (epp->fd [1] != epp->fd [0]) close (epp->fd [1]); if (s_epipe_new (&epn)) return -1; if (epp->len) { if (dup2 (epn.fd [0], epp->fd [0]) < 0) croak ("unable to dup over old event pipe"); /* should not croak */ close (epn.fd [0]); if (epn.fd [0] == epn.fd [1]) epn.fd [1] = epp->fd [0]; epn.fd [0] = epp->fd [0]; } *epp = epn; return 0; } #define s_epipe_fd(epp) ((epp)->fd [0]) static int s_epipe_wait (s_epipe *epp) { dTHX; #if SCHMORP_H_PREFER_SELECT fd_set rfd; int fd = s_epipe_fd (epp); FD_ZERO (&rfd); FD_SET (fd, &rfd); return PerlSock_select (fd + 1, &rfd, 0, 0, 0); #else /* poll is preferable on posix systems */ struct pollfd pfd; pfd.fd = s_epipe_fd (epp); pfd.events = POLLIN; return poll (&pfd, 1, -1); #endif } #endif Async-Interrupt-1.25/typemap0000644000000000000000000000020611230156305014602 0ustar rootrootasync_t * T_ASYNC s_epipe * T_EPIPE INPUT T_ASYNC $var = SvASYNC ($arg); T_EPIPE $var = INT2PTR (s_epipe *, SvIVX (SvRV ($arg))) Async-Interrupt-1.25/MANIFEST0000644000000000000000000000053613457035364014355 0ustar rootrootREADME Changes MANIFEST COPYING Makefile.PL schmorp.h Interrupt.pm Interrupt.xs typemap ecb.h t/00_load.t t/01_basic.t t/02_pipe.t t/03_signal.t t/04_apipe.t t/05_var.t t/06_epipe.t META.yml Module YAML meta-data (added by MakeMaker) META.json Module JSON meta-data (added by MakeMaker) Async-Interrupt-1.25/Makefile.PL0000644000000000000000000000111113456573507015171 0ustar rootrootuse ExtUtils::MakeMaker; use Canary::Stability Async::Interrupt => 1, 5.008; # apparently PL_sighandlerp was introduced with 5.008 - correct me if wrong WriteMakefile( dist => { PREOP => 'pod2text Interrupt.pm | tee README >$(DISTVNAME)/README; chmod -R u=rwX,go=rX . ;', COMPRESS => 'gzip -9v', SUFFIX => '.gz', }, PREREQ_PM => { common::sense => 0, }, CONFIGURE_REQUIRES => { ExtUtils::MakeMaker => 6.52, Canary::Stability => 0 }, NAME => "Async::Interrupt", VERSION_FROM => "Interrupt.pm", ); Async-Interrupt-1.25/Changes0000644000000000000000000000665013457035361014517 0ustar rootrootRevision history for Perl extension Async::Interrupt. 1.25 Sat Apr 20 12:42:25 CEST 2019 - fix dependency on Canary::Stability (reported by Ross Opperman). 1.24 Tue Apr 17 21:24:11 CEST 2018 - actually rewnew was missing, not wrongly documented. silly. 1.23 Tue Apr 17 21:18:24 CEST 2018 - ->renew is actually called ->post_fork, fix documentation. - use stability canary. 1.22 Thu Jan 18 17:43:14 CET 2018 - further USE_SOCKETS_AS_HANDLES fixes (Z59). 1.21 Wed Feb 11 20:31:01 CET 2015 - upgrade ecb.h for C11 compatibility. 1.2 Fri Apr 11 06:22:38 CEST 2014 - perl5porters broke Async::Interrupt, BDB, EV, IO::AIO, OpenCL without warning by switching the meaning of USE_SOCKETS_AS_HANDLES in 5.18. What's so attractive about giving a shit about backwards compatibility - I will never understand. 1.1 Wed Apr 25 00:46:08 CEST 2012 - new $async->handle method. - new $async->pipe_drain method. - use memory fences for !x86, and x86 future proofing. use libecb for implementation. 1.05 Sat May 15 02:06:33 CEST 2010 - implement $epipe->signal_func method. 1.04 Wed Mar 31 02:46:49 CEST 2010 - a double fork partially killed the event pipe (great testcase by dormando). affects IO::AIO, BDB and Async::Interrupt. 1.03 Tue Nov 24 14:31:10 CET 2009 - port to loser platform. 1.02 Tue Sep 1 18:41:09 CEST 2009 - prototypes for sig2name/sig2num were missing. 1.01 Wed Aug 5 13:50:59 CEST 2009 - evpipe->wait did immediately return on !windows. 1.0 Thu Jul 30 05:58:55 CEST 2009 - implement signal_hysteresis. - implement scope_block_func. - implement sig2name/sig2num convenience functions. 0.6 Sat Jul 18 07:09:33 CEST 2009 - add autodrain setting. - added Async::Interrupt::EventPipe class. - fixed a potential race issue by removing the internal epipe state. - destroying asyncs inside their handler callback could lead to segfaults. - destroying an interrupt object did not properly remove it from the asyncs list (classical case of side-effect-inside-assert). 0.501 Fri Jul 17 16:58:51 CEST 2009 - do no longer errornously do operations on fd 0 if no pipe is associated with the interrupt object. 0.5 Fri Jul 17 03:53:21 CEST 2009 - INCOMPATIBLE CHANGE: signalling the value 0 is no longer allowed. - added automatic pipe creation code, including post_fork method. - added ->c_var method, and the ability to use a perl scalar as signal checker. 0.042 Tue Jul 14 21:51:04 CEST 2009 - enforce initialisation of perl's signal handling framework, avoiding crashes otherwise. - switched to common::sense. - freely sprinkle around more volatiles. - fix initialisation code (XSLoader). - ported to win32. 0.041 Sun Jul 12 18:32:46 CEST 2009 - oh my, I forgot to include the typemap. - improved documentation. 0.04 Sun Jul 12 00:24:02 CEST 2009 - added ability to block the pipe write temporarily. - added the ability to call signal when the process receives a (POSIX) signal. - removed debugging output in constructor. - support eventfd instead of a pipe (untested). 0.03 Fri Jul 3 23:11:05 CEST 2009 - port to perl <= 5.8.9. 0.02 Thu Jul 2 17:17:30 CEST 2009 - first release, rather untested. 0.01 Thu Jul 2 13:18:00 CEST 2009 - original version; cloned from Convert::Scalar. Async-Interrupt-1.25/ecb.h0000644000000000000000000010523713374401463014125 0ustar rootroot/* * libecb - http://software.schmorp.de/pkg/libecb * * Copyright (©) 2009-2015 Marc Alexander Lehmann * Copyright (©) 2011 Emanuele Giaquinta * All rights reserved. * * Redistribution and use in source and binary forms, with or without modifica- * tion, are permitted provided that the following conditions are met: * * 1. Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER- * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE- * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH- * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED * OF THE POSSIBILITY OF SUCH DAMAGE. * * Alternatively, the contents of this file may be used under the terms of * the GNU General Public License ("GPL") version 2 or any later version, * in which case the provisions of the GPL are applicable instead of * the above. If you wish to allow the use of your version of this file * only under the terms of the GPL and not to allow others to use your * version of this file under the BSD license, indicate your decision * by deleting the provisions above and replace them with the notice * and other provisions required by the GPL. If you do not delete the * provisions above, a recipient may use your version of this file under * either the BSD or the GPL. */ #ifndef ECB_H #define ECB_H /* 16 bits major, 16 bits minor */ #define ECB_VERSION 0x00010005 #ifdef _WIN32 typedef signed char int8_t; typedef unsigned char uint8_t; typedef signed short int16_t; typedef unsigned short uint16_t; typedef signed int int32_t; typedef unsigned int uint32_t; #if __GNUC__ typedef signed long long int64_t; typedef unsigned long long uint64_t; #else /* _MSC_VER || __BORLANDC__ */ typedef signed __int64 int64_t; typedef unsigned __int64 uint64_t; #endif #ifdef _WIN64 #define ECB_PTRSIZE 8 typedef uint64_t uintptr_t; typedef int64_t intptr_t; #else #define ECB_PTRSIZE 4 typedef uint32_t uintptr_t; typedef int32_t intptr_t; #endif #else #include #if (defined INTPTR_MAX ? INTPTR_MAX : ULONG_MAX) > 0xffffffffU #define ECB_PTRSIZE 8 #else #define ECB_PTRSIZE 4 #endif #endif #define ECB_GCC_AMD64 (__amd64 || __amd64__ || __x86_64 || __x86_64__) #define ECB_MSVC_AMD64 (_M_AMD64 || _M_X64) /* work around x32 idiocy by defining proper macros */ #if ECB_GCC_AMD64 || ECB_MSVC_AMD64 #if _ILP32 #define ECB_AMD64_X32 1 #else #define ECB_AMD64 1 #endif #endif /* many compilers define _GNUC_ to some versions but then only implement * what their idiot authors think are the "more important" extensions, * causing enormous grief in return for some better fake benchmark numbers. * or so. * we try to detect these and simply assume they are not gcc - if they have * an issue with that they should have done it right in the first place. */ #if !defined __GNUC_MINOR__ || defined __INTEL_COMPILER || defined __SUNPRO_C || defined __SUNPRO_CC || defined __llvm__ || defined __clang__ #define ECB_GCC_VERSION(major,minor) 0 #else #define ECB_GCC_VERSION(major,minor) (__GNUC__ > (major) || (__GNUC__ == (major) && __GNUC_MINOR__ >= (minor))) #endif #define ECB_CLANG_VERSION(major,minor) (__clang_major__ > (major) || (__clang_major__ == (major) && __clang_minor__ >= (minor))) #if __clang__ && defined __has_builtin #define ECB_CLANG_BUILTIN(x) __has_builtin (x) #else #define ECB_CLANG_BUILTIN(x) 0 #endif #if __clang__ && defined __has_extension #define ECB_CLANG_EXTENSION(x) __has_extension (x) #else #define ECB_CLANG_EXTENSION(x) 0 #endif #define ECB_CPP (__cplusplus+0) #define ECB_CPP11 (__cplusplus >= 201103L) #define ECB_CPP14 (__cplusplus >= 201402L) #define ECB_CPP17 (__cplusplus >= 201703L) #if ECB_CPP #define ECB_C 0 #define ECB_STDC_VERSION 0 #else #define ECB_C 1 #define ECB_STDC_VERSION __STDC_VERSION__ #endif #define ECB_C99 (ECB_STDC_VERSION >= 199901L) #define ECB_C11 (ECB_STDC_VERSION >= 201112L) #define ECB_C17 (ECB_STDC_VERSION >= 201710L) #if ECB_CPP #define ECB_EXTERN_C extern "C" #define ECB_EXTERN_C_BEG ECB_EXTERN_C { #define ECB_EXTERN_C_END } #else #define ECB_EXTERN_C extern #define ECB_EXTERN_C_BEG #define ECB_EXTERN_C_END #endif /*****************************************************************************/ /* ECB_NO_THREADS - ecb is not used by multiple threads, ever */ /* ECB_NO_SMP - ecb might be used in multiple threads, but only on a single cpu */ #if ECB_NO_THREADS #define ECB_NO_SMP 1 #endif #if ECB_NO_SMP #define ECB_MEMORY_FENCE do { } while (0) #endif /* http://www-01.ibm.com/support/knowledgecenter/SSGH3R_13.1.0/com.ibm.xlcpp131.aix.doc/compiler_ref/compiler_builtins.html */ #if __xlC__ && ECB_CPP #include #endif #if 1400 <= _MSC_VER #include /* fence functions _ReadBarrier, also bit search functions _BitScanReverse */ #endif #ifndef ECB_MEMORY_FENCE #if ECB_GCC_VERSION(2,5) || defined __INTEL_COMPILER || (__llvm__ && __GNUC__) || __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110 #if __i386 || __i386__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("lock; orb $0, -1(%%esp)" : : : "memory") #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory") #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("" : : : "memory") #elif ECB_GCC_AMD64 #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mfence" : : : "memory") #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("" : : : "memory") #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("" : : : "memory") #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("sync" : : : "memory") #elif defined __ARM_ARCH_2__ \ || defined __ARM_ARCH_3__ || defined __ARM_ARCH_3M__ \ || defined __ARM_ARCH_4__ || defined __ARM_ARCH_4T__ \ || defined __ARM_ARCH_5__ || defined __ARM_ARCH_5E__ \ || defined __ARM_ARCH_5T__ || defined __ARM_ARCH_5TE__ \ || defined __ARM_ARCH_5TEJ__ /* should not need any, unless running old code on newer cpu - arm doesn't support that */ #elif defined __ARM_ARCH_6__ || defined __ARM_ARCH_6J__ \ || defined __ARM_ARCH_6K__ || defined __ARM_ARCH_6ZK__ \ || defined __ARM_ARCH_6T2__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory") #elif defined __ARM_ARCH_7__ || defined __ARM_ARCH_7A__ \ || defined __ARM_ARCH_7R__ || defined __ARM_ARCH_7M__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb" : : : "memory") #elif __aarch64__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("dmb ish" : : : "memory") #elif (__sparc || __sparc__) && !(__sparc_v8__ || defined __sparcv8) #define ECB_MEMORY_FENCE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad | #StoreStore | #StoreLoad" : : : "memory") #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("membar #LoadStore | #LoadLoad" : : : "memory") #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("membar #LoadStore | #StoreStore") #elif defined __s390__ || defined __s390x__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("bcr 15,0" : : : "memory") #elif defined __mips__ /* GNU/Linux emulates sync on mips1 architectures, so we force its use */ /* anybody else who still uses mips1 is supposed to send in their version, with detection code. */ #define ECB_MEMORY_FENCE __asm__ __volatile__ (".set mips2; sync; .set mips0" : : : "memory") #elif defined __alpha__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mb" : : : "memory") #elif defined __hppa__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory") #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("") #elif defined __ia64__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mf" : : : "memory") #elif defined __m68k__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory") #elif defined __m88k__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("tb1 0,%%r0,128" : : : "memory") #elif defined __sh__ #define ECB_MEMORY_FENCE __asm__ __volatile__ ("" : : : "memory") #endif #endif #endif #ifndef ECB_MEMORY_FENCE #if ECB_GCC_VERSION(4,7) /* see comment below (stdatomic.h) about the C11 memory model. */ #define ECB_MEMORY_FENCE __atomic_thread_fence (__ATOMIC_SEQ_CST) #define ECB_MEMORY_FENCE_ACQUIRE __atomic_thread_fence (__ATOMIC_ACQUIRE) #define ECB_MEMORY_FENCE_RELEASE __atomic_thread_fence (__ATOMIC_RELEASE) #elif ECB_CLANG_EXTENSION(c_atomic) /* see comment below (stdatomic.h) about the C11 memory model. */ #define ECB_MEMORY_FENCE __c11_atomic_thread_fence (__ATOMIC_SEQ_CST) #define ECB_MEMORY_FENCE_ACQUIRE __c11_atomic_thread_fence (__ATOMIC_ACQUIRE) #define ECB_MEMORY_FENCE_RELEASE __c11_atomic_thread_fence (__ATOMIC_RELEASE) #elif ECB_GCC_VERSION(4,4) || defined __INTEL_COMPILER || defined __clang__ #define ECB_MEMORY_FENCE __sync_synchronize () #elif _MSC_VER >= 1500 /* VC++ 2008 */ /* apparently, microsoft broke all the memory barrier stuff in Visual Studio 2008... */ #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) #define ECB_MEMORY_FENCE _ReadWriteBarrier (); MemoryBarrier() #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier (); MemoryBarrier() /* according to msdn, _ReadBarrier is not a load fence */ #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier (); MemoryBarrier() #elif _MSC_VER >= 1400 /* VC++ 2005 */ #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier) #define ECB_MEMORY_FENCE _ReadWriteBarrier () #define ECB_MEMORY_FENCE_ACQUIRE _ReadWriteBarrier () /* according to msdn, _ReadBarrier is not a load fence */ #define ECB_MEMORY_FENCE_RELEASE _WriteBarrier () #elif defined _WIN32 #include #define ECB_MEMORY_FENCE MemoryBarrier () /* actually just xchg on x86... scary */ #elif __SUNPRO_C >= 0x5110 || __SUNPRO_CC >= 0x5110 #include #define ECB_MEMORY_FENCE __machine_rw_barrier () #define ECB_MEMORY_FENCE_ACQUIRE __machine_r_barrier () #define ECB_MEMORY_FENCE_RELEASE __machine_w_barrier () #elif __xlC__ #define ECB_MEMORY_FENCE __sync () #endif #endif #ifndef ECB_MEMORY_FENCE #if ECB_C11 && !defined __STDC_NO_ATOMICS__ /* we assume that these memory fences work on all variables/all memory accesses, */ /* not just C11 atomics and atomic accesses */ #include /* Unfortunately, neither gcc 4.7 nor clang 3.1 generate any instructions for */ /* any fence other than seq_cst, which isn't very efficient for us. */ /* Why that is, we don't know - either the C11 memory model is quite useless */ /* for most usages, or gcc and clang have a bug */ /* I *currently* lean towards the latter, and inefficiently implement */ /* all three of ecb's fences as a seq_cst fence */ /* Update, gcc-4.8 generates mfence for all c++ fences, but nothing */ /* for all __atomic_thread_fence's except seq_cst */ #define ECB_MEMORY_FENCE atomic_thread_fence (memory_order_seq_cst) #endif #endif #ifndef ECB_MEMORY_FENCE #if !ECB_AVOID_PTHREADS /* * if you get undefined symbol references to pthread_mutex_lock, * or failure to find pthread.h, then you should implement * the ECB_MEMORY_FENCE operations for your cpu/compiler * OR provide pthread.h and link against the posix thread library * of your system. */ #include #define ECB_NEEDS_PTHREADS 1 #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1 static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER; #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0) #endif #endif #if !defined ECB_MEMORY_FENCE_ACQUIRE && defined ECB_MEMORY_FENCE #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE #endif #if !defined ECB_MEMORY_FENCE_RELEASE && defined ECB_MEMORY_FENCE #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE #endif /*****************************************************************************/ #if ECB_CPP #define ecb_inline static inline #elif ECB_GCC_VERSION(2,5) #define ecb_inline static __inline__ #elif ECB_C99 #define ecb_inline static inline #else #define ecb_inline static #endif #if ECB_GCC_VERSION(3,3) #define ecb_restrict __restrict__ #elif ECB_C99 #define ecb_restrict restrict #else #define ecb_restrict #endif typedef int ecb_bool; #define ECB_CONCAT_(a, b) a ## b #define ECB_CONCAT(a, b) ECB_CONCAT_(a, b) #define ECB_STRINGIFY_(a) # a #define ECB_STRINGIFY(a) ECB_STRINGIFY_(a) #define ECB_STRINGIFY_EXPR(expr) ((expr), ECB_STRINGIFY_ (expr)) #define ecb_function_ ecb_inline #if ECB_GCC_VERSION(3,1) || ECB_CLANG_VERSION(2,8) #define ecb_attribute(attrlist) __attribute__ (attrlist) #else #define ecb_attribute(attrlist) #endif #if ECB_GCC_VERSION(3,1) || ECB_CLANG_BUILTIN(__builtin_constant_p) #define ecb_is_constant(expr) __builtin_constant_p (expr) #else /* possible C11 impl for integral types typedef struct ecb_is_constant_struct ecb_is_constant_struct; #define ecb_is_constant(expr) _Generic ((1 ? (struct ecb_is_constant_struct *)0 : (void *)((expr) - (expr)), ecb_is_constant_struct *: 0, default: 1)) */ #define ecb_is_constant(expr) 0 #endif #if ECB_GCC_VERSION(3,1) || ECB_CLANG_BUILTIN(__builtin_expect) #define ecb_expect(expr,value) __builtin_expect ((expr),(value)) #else #define ecb_expect(expr,value) (expr) #endif #if ECB_GCC_VERSION(3,1) || ECB_CLANG_BUILTIN(__builtin_prefetch) #define ecb_prefetch(addr,rw,locality) __builtin_prefetch (addr, rw, locality) #else #define ecb_prefetch(addr,rw,locality) #endif /* no emulation for ecb_decltype */ #if ECB_CPP11 // older implementations might have problems with decltype(x)::type, work around it template struct ecb_decltype_t { typedef T type; }; #define ecb_decltype(x) ecb_decltype_t::type #elif ECB_GCC_VERSION(3,0) || ECB_CLANG_VERSION(2,8) #define ecb_decltype(x) __typeof__ (x) #endif #if _MSC_VER >= 1300 #define ecb_deprecated __declspec (deprecated) #else #define ecb_deprecated ecb_attribute ((__deprecated__)) #endif #if _MSC_VER >= 1500 #define ecb_deprecated_message(msg) __declspec (deprecated (msg)) #elif ECB_GCC_VERSION(4,5) #define ecb_deprecated_message(msg) ecb_attribute ((__deprecated__ (msg)) #else #define ecb_deprecated_message(msg) ecb_deprecated #endif #if _MSC_VER >= 1400 #define ecb_noinline __declspec (noinline) #else #define ecb_noinline ecb_attribute ((__noinline__)) #endif #define ecb_unused ecb_attribute ((__unused__)) #define ecb_const ecb_attribute ((__const__)) #define ecb_pure ecb_attribute ((__pure__)) #if ECB_C11 || __IBMC_NORETURN /* http://www-01.ibm.com/support/knowledgecenter/SSGH3R_13.1.0/com.ibm.xlcpp131.aix.doc/language_ref/noreturn.html */ #define ecb_noreturn _Noreturn #elif ECB_CPP11 #define ecb_noreturn [[noreturn]] #elif _MSC_VER >= 1200 /* http://msdn.microsoft.com/en-us/library/k6ktzx3s.aspx */ #define ecb_noreturn __declspec (noreturn) #else #define ecb_noreturn ecb_attribute ((__noreturn__)) #endif #if ECB_GCC_VERSION(4,3) #define ecb_artificial ecb_attribute ((__artificial__)) #define ecb_hot ecb_attribute ((__hot__)) #define ecb_cold ecb_attribute ((__cold__)) #else #define ecb_artificial #define ecb_hot #define ecb_cold #endif /* put around conditional expressions if you are very sure that the */ /* expression is mostly true or mostly false. note that these return */ /* booleans, not the expression. */ #define ecb_expect_false(expr) ecb_expect (!!(expr), 0) #define ecb_expect_true(expr) ecb_expect (!!(expr), 1) /* for compatibility to the rest of the world */ #define ecb_likely(expr) ecb_expect_true (expr) #define ecb_unlikely(expr) ecb_expect_false (expr) /* count trailing zero bits and count # of one bits */ #if ECB_GCC_VERSION(3,4) \ || (ECB_CLANG_BUILTIN(__builtin_clz) && ECB_CLANG_BUILTIN(__builtin_clzll) \ && ECB_CLANG_BUILTIN(__builtin_ctz) && ECB_CLANG_BUILTIN(__builtin_ctzll) \ && ECB_CLANG_BUILTIN(__builtin_popcount)) /* we assume int == 32 bit, long == 32 or 64 bit and long long == 64 bit */ #define ecb_ld32(x) (__builtin_clz (x) ^ 31) #define ecb_ld64(x) (__builtin_clzll (x) ^ 63) #define ecb_ctz32(x) __builtin_ctz (x) #define ecb_ctz64(x) __builtin_ctzll (x) #define ecb_popcount32(x) __builtin_popcount (x) /* no popcountll */ #else ecb_function_ ecb_const int ecb_ctz32 (uint32_t x); ecb_function_ ecb_const int ecb_ctz32 (uint32_t x) { #if 1400 <= _MSC_VER && (_M_IX86 || _M_X64 || _M_IA64 || _M_ARM) unsigned long r; _BitScanForward (&r, x); return (int)r; #else int r = 0; x &= ~x + 1; /* this isolates the lowest bit */ #if ECB_branchless_on_i386 r += !!(x & 0xaaaaaaaa) << 0; r += !!(x & 0xcccccccc) << 1; r += !!(x & 0xf0f0f0f0) << 2; r += !!(x & 0xff00ff00) << 3; r += !!(x & 0xffff0000) << 4; #else if (x & 0xaaaaaaaa) r += 1; if (x & 0xcccccccc) r += 2; if (x & 0xf0f0f0f0) r += 4; if (x & 0xff00ff00) r += 8; if (x & 0xffff0000) r += 16; #endif return r; #endif } ecb_function_ ecb_const int ecb_ctz64 (uint64_t x); ecb_function_ ecb_const int ecb_ctz64 (uint64_t x) { #if 1400 <= _MSC_VER && (_M_X64 || _M_IA64 || _M_ARM) unsigned long r; _BitScanForward64 (&r, x); return (int)r; #else int shift = x & 0xffffffff ? 0 : 32; return ecb_ctz32 (x >> shift) + shift; #endif } ecb_function_ ecb_const int ecb_popcount32 (uint32_t x); ecb_function_ ecb_const int ecb_popcount32 (uint32_t x) { x -= (x >> 1) & 0x55555555; x = ((x >> 2) & 0x33333333) + (x & 0x33333333); x = ((x >> 4) + x) & 0x0f0f0f0f; x *= 0x01010101; return x >> 24; } ecb_function_ ecb_const int ecb_ld32 (uint32_t x); ecb_function_ ecb_const int ecb_ld32 (uint32_t x) { #if 1400 <= _MSC_VER && (_M_IX86 || _M_X64 || _M_IA64 || _M_ARM) unsigned long r; _BitScanReverse (&r, x); return (int)r; #else int r = 0; if (x >> 16) { x >>= 16; r += 16; } if (x >> 8) { x >>= 8; r += 8; } if (x >> 4) { x >>= 4; r += 4; } if (x >> 2) { x >>= 2; r += 2; } if (x >> 1) { r += 1; } return r; #endif } ecb_function_ ecb_const int ecb_ld64 (uint64_t x); ecb_function_ ecb_const int ecb_ld64 (uint64_t x) { #if 1400 <= _MSC_VER && (_M_X64 || _M_IA64 || _M_ARM) unsigned long r; _BitScanReverse64 (&r, x); return (int)r; #else int r = 0; if (x >> 32) { x >>= 32; r += 32; } return r + ecb_ld32 (x); #endif } #endif ecb_function_ ecb_const ecb_bool ecb_is_pot32 (uint32_t x); ecb_function_ ecb_const ecb_bool ecb_is_pot32 (uint32_t x) { return !(x & (x - 1)); } ecb_function_ ecb_const ecb_bool ecb_is_pot64 (uint64_t x); ecb_function_ ecb_const ecb_bool ecb_is_pot64 (uint64_t x) { return !(x & (x - 1)); } ecb_function_ ecb_const uint8_t ecb_bitrev8 (uint8_t x); ecb_function_ ecb_const uint8_t ecb_bitrev8 (uint8_t x) { return ( (x * 0x0802U & 0x22110U) | (x * 0x8020U & 0x88440U)) * 0x10101U >> 16; } ecb_function_ ecb_const uint16_t ecb_bitrev16 (uint16_t x); ecb_function_ ecb_const uint16_t ecb_bitrev16 (uint16_t x) { x = ((x >> 1) & 0x5555) | ((x & 0x5555) << 1); x = ((x >> 2) & 0x3333) | ((x & 0x3333) << 2); x = ((x >> 4) & 0x0f0f) | ((x & 0x0f0f) << 4); x = ( x >> 8 ) | ( x << 8); return x; } ecb_function_ ecb_const uint32_t ecb_bitrev32 (uint32_t x); ecb_function_ ecb_const uint32_t ecb_bitrev32 (uint32_t x) { x = ((x >> 1) & 0x55555555) | ((x & 0x55555555) << 1); x = ((x >> 2) & 0x33333333) | ((x & 0x33333333) << 2); x = ((x >> 4) & 0x0f0f0f0f) | ((x & 0x0f0f0f0f) << 4); x = ((x >> 8) & 0x00ff00ff) | ((x & 0x00ff00ff) << 8); x = ( x >> 16 ) | ( x << 16); return x; } /* popcount64 is only available on 64 bit cpus as gcc builtin */ /* so for this version we are lazy */ ecb_function_ ecb_const int ecb_popcount64 (uint64_t x); ecb_function_ ecb_const int ecb_popcount64 (uint64_t x) { return ecb_popcount32 (x) + ecb_popcount32 (x >> 32); } ecb_inline ecb_const uint8_t ecb_rotl8 (uint8_t x, unsigned int count); ecb_inline ecb_const uint8_t ecb_rotr8 (uint8_t x, unsigned int count); ecb_inline ecb_const uint16_t ecb_rotl16 (uint16_t x, unsigned int count); ecb_inline ecb_const uint16_t ecb_rotr16 (uint16_t x, unsigned int count); ecb_inline ecb_const uint32_t ecb_rotl32 (uint32_t x, unsigned int count); ecb_inline ecb_const uint32_t ecb_rotr32 (uint32_t x, unsigned int count); ecb_inline ecb_const uint64_t ecb_rotl64 (uint64_t x, unsigned int count); ecb_inline ecb_const uint64_t ecb_rotr64 (uint64_t x, unsigned int count); ecb_inline ecb_const uint8_t ecb_rotl8 (uint8_t x, unsigned int count) { return (x >> ( 8 - count)) | (x << count); } ecb_inline ecb_const uint8_t ecb_rotr8 (uint8_t x, unsigned int count) { return (x << ( 8 - count)) | (x >> count); } ecb_inline ecb_const uint16_t ecb_rotl16 (uint16_t x, unsigned int count) { return (x >> (16 - count)) | (x << count); } ecb_inline ecb_const uint16_t ecb_rotr16 (uint16_t x, unsigned int count) { return (x << (16 - count)) | (x >> count); } ecb_inline ecb_const uint32_t ecb_rotl32 (uint32_t x, unsigned int count) { return (x >> (32 - count)) | (x << count); } ecb_inline ecb_const uint32_t ecb_rotr32 (uint32_t x, unsigned int count) { return (x << (32 - count)) | (x >> count); } ecb_inline ecb_const uint64_t ecb_rotl64 (uint64_t x, unsigned int count) { return (x >> (64 - count)) | (x << count); } ecb_inline ecb_const uint64_t ecb_rotr64 (uint64_t x, unsigned int count) { return (x << (64 - count)) | (x >> count); } #if ECB_GCC_VERSION(4,3) || (ECB_CLANG_BUILTIN(__builtin_bswap32) && ECB_CLANG_BUILTIN(__builtin_bswap64)) #if ECB_GCC_VERSION(4,8) || ECB_CLANG_BUILTIN(__builtin_bswap16) #define ecb_bswap16(x) __builtin_bswap16 (x) #else #define ecb_bswap16(x) (__builtin_bswap32 (x) >> 16) #endif #define ecb_bswap32(x) __builtin_bswap32 (x) #define ecb_bswap64(x) __builtin_bswap64 (x) #elif _MSC_VER #include #define ecb_bswap16(x) ((uint16_t)_byteswap_ushort ((uint16_t)(x))) #define ecb_bswap32(x) ((uint32_t)_byteswap_ulong ((uint32_t)(x))) #define ecb_bswap64(x) ((uint64_t)_byteswap_uint64 ((uint64_t)(x))) #else ecb_function_ ecb_const uint16_t ecb_bswap16 (uint16_t x); ecb_function_ ecb_const uint16_t ecb_bswap16 (uint16_t x) { return ecb_rotl16 (x, 8); } ecb_function_ ecb_const uint32_t ecb_bswap32 (uint32_t x); ecb_function_ ecb_const uint32_t ecb_bswap32 (uint32_t x) { return (((uint32_t)ecb_bswap16 (x)) << 16) | ecb_bswap16 (x >> 16); } ecb_function_ ecb_const uint64_t ecb_bswap64 (uint64_t x); ecb_function_ ecb_const uint64_t ecb_bswap64 (uint64_t x) { return (((uint64_t)ecb_bswap32 (x)) << 32) | ecb_bswap32 (x >> 32); } #endif #if ECB_GCC_VERSION(4,5) || ECB_CLANG_BUILTIN(__builtin_unreachable) #define ecb_unreachable() __builtin_unreachable () #else /* this seems to work fine, but gcc always emits a warning for it :/ */ ecb_inline ecb_noreturn void ecb_unreachable (void); ecb_inline ecb_noreturn void ecb_unreachable (void) { } #endif /* try to tell the compiler that some condition is definitely true */ #define ecb_assume(cond) if (!(cond)) ecb_unreachable (); else 0 ecb_inline ecb_const uint32_t ecb_byteorder_helper (void); ecb_inline ecb_const uint32_t ecb_byteorder_helper (void) { /* the union code still generates code under pressure in gcc, */ /* but less than using pointers, and always seems to */ /* successfully return a constant. */ /* the reason why we have this horrible preprocessor mess */ /* is to avoid it in all cases, at least on common architectures */ /* or when using a recent enough gcc version (>= 4.6) */ #if (defined __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) \ || ((__i386 || __i386__ || _M_IX86 || ECB_GCC_AMD64 || ECB_MSVC_AMD64) && !__VOS__) #define ECB_LITTLE_ENDIAN 1 return 0x44332211; #elif (defined __BYTE_ORDER__ && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) \ || ((__AARCH64EB__ || __MIPSEB__ || __ARMEB__) && !__VOS__) #define ECB_BIG_ENDIAN 1 return 0x11223344; #else union { uint8_t c[4]; uint32_t u; } u = { 0x11, 0x22, 0x33, 0x44 }; return u.u; #endif } ecb_inline ecb_const ecb_bool ecb_big_endian (void); ecb_inline ecb_const ecb_bool ecb_big_endian (void) { return ecb_byteorder_helper () == 0x11223344; } ecb_inline ecb_const ecb_bool ecb_little_endian (void); ecb_inline ecb_const ecb_bool ecb_little_endian (void) { return ecb_byteorder_helper () == 0x44332211; } #if ECB_GCC_VERSION(3,0) || ECB_C99 #define ecb_mod(m,n) ((m) % (n) + ((m) % (n) < 0 ? (n) : 0)) #else #define ecb_mod(m,n) ((m) < 0 ? ((n) - 1 - ((-1 - (m)) % (n))) : ((m) % (n))) #endif #if ECB_CPP template static inline T ecb_div_rd (T val, T div) { return val < 0 ? - ((-val + div - 1) / div) : (val ) / div; } template static inline T ecb_div_ru (T val, T div) { return val < 0 ? - ((-val ) / div) : (val + div - 1) / div; } #else #define ecb_div_rd(val,div) ((val) < 0 ? - ((-(val) + (div) - 1) / (div)) : ((val) ) / (div)) #define ecb_div_ru(val,div) ((val) < 0 ? - ((-(val) ) / (div)) : ((val) + (div) - 1) / (div)) #endif #if ecb_cplusplus_does_not_suck /* does not work for local types (http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm) */ template static inline int ecb_array_length (const T (&arr)[N]) { return N; } #else #define ecb_array_length(name) (sizeof (name) / sizeof (name [0])) #endif ecb_function_ ecb_const uint32_t ecb_binary16_to_binary32 (uint32_t x); ecb_function_ ecb_const uint32_t ecb_binary16_to_binary32 (uint32_t x) { unsigned int s = (x & 0x8000) << (31 - 15); int e = (x >> 10) & 0x001f; unsigned int m = x & 0x03ff; if (ecb_expect_false (e == 31)) /* infinity or NaN */ e = 255 - (127 - 15); else if (ecb_expect_false (!e)) { if (ecb_expect_true (!m)) /* zero, handled by code below by forcing e to 0 */ e = 0 - (127 - 15); else { /* subnormal, renormalise */ unsigned int s = 10 - ecb_ld32 (m); m = (m << s) & 0x3ff; /* mask implicit bit */ e -= s - 1; } } /* e and m now are normalised, or zero, (or inf or nan) */ e += 127 - 15; return s | (e << 23) | (m << (23 - 10)); } ecb_function_ ecb_const uint16_t ecb_binary32_to_binary16 (uint32_t x); ecb_function_ ecb_const uint16_t ecb_binary32_to_binary16 (uint32_t x) { unsigned int s = (x >> 16) & 0x00008000; /* sign bit, the easy part */ unsigned int e = ((x >> 23) & 0x000000ff) - (127 - 15); /* the desired exponent */ unsigned int m = x & 0x007fffff; x &= 0x7fffffff; /* if it's within range of binary16 normals, use fast path */ if (ecb_expect_true (0x38800000 <= x && x <= 0x477fefff)) { /* mantissa round-to-even */ m += 0x00000fff + ((m >> (23 - 10)) & 1); /* handle overflow */ if (ecb_expect_false (m >= 0x00800000)) { m >>= 1; e += 1; } return s | (e << 10) | (m >> (23 - 10)); } /* handle large numbers and infinity */ if (ecb_expect_true (0x477fefff < x && x <= 0x7f800000)) return s | 0x7c00; /* handle zero, subnormals and small numbers */ if (ecb_expect_true (x < 0x38800000)) { /* zero */ if (ecb_expect_true (!x)) return s; /* handle subnormals */ /* too small, will be zero */ if (e < (14 - 24)) /* might not be sharp, but is good enough */ return s; m |= 0x00800000; /* make implicit bit explicit */ /* very tricky - we need to round to the nearest e (+10) bit value */ { unsigned int bits = 14 - e; unsigned int half = (1 << (bits - 1)) - 1; unsigned int even = (m >> bits) & 1; /* if this overflows, we will end up with a normalised number */ m = (m + half + even) >> bits; } return s | m; } /* handle NaNs, preserve leftmost nan bits, but make sure we don't turn them into infinities */ m >>= 13; return s | 0x7c00 | m | !m; } /*******************************************************************************/ /* floating point stuff, can be disabled by defining ECB_NO_LIBM */ /* basically, everything uses "ieee pure-endian" floating point numbers */ /* the only noteworthy exception is ancient armle, which uses order 43218765 */ #if 0 \ || __i386 || __i386__ \ || ECB_GCC_AMD64 \ || __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__ \ || defined __s390__ || defined __s390x__ \ || defined __mips__ \ || defined __alpha__ \ || defined __hppa__ \ || defined __ia64__ \ || defined __m68k__ \ || defined __m88k__ \ || defined __sh__ \ || defined _M_IX86 || defined ECB_MSVC_AMD64 || defined _M_IA64 \ || (defined __arm__ && (defined __ARM_EABI__ || defined __EABI__ || defined __VFP_FP__ || defined _WIN32_WCE || defined __ANDROID__)) \ || defined __aarch64__ #define ECB_STDFP 1 #include /* for memcpy */ #else #define ECB_STDFP 0 #endif #ifndef ECB_NO_LIBM #include /* for frexp*, ldexp*, INFINITY, NAN */ /* only the oldest of old doesn't have this one. solaris. */ #ifdef INFINITY #define ECB_INFINITY INFINITY #else #define ECB_INFINITY HUGE_VAL #endif #ifdef NAN #define ECB_NAN NAN #else #define ECB_NAN ECB_INFINITY #endif #if ECB_C99 || _XOPEN_VERSION >= 600 || _POSIX_VERSION >= 200112L #define ecb_ldexpf(x,e) ldexpf ((x), (e)) #define ecb_frexpf(x,e) frexpf ((x), (e)) #else #define ecb_ldexpf(x,e) (float) ldexp ((double) (x), (e)) #define ecb_frexpf(x,e) (float) frexp ((double) (x), (e)) #endif /* convert a float to ieee single/binary32 */ ecb_function_ ecb_const uint32_t ecb_float_to_binary32 (float x); ecb_function_ ecb_const uint32_t ecb_float_to_binary32 (float x) { uint32_t r; #if ECB_STDFP memcpy (&r, &x, 4); #else /* slow emulation, works for anything but -0 */ uint32_t m; int e; if (x == 0e0f ) return 0x00000000U; if (x > +3.40282346638528860e+38f) return 0x7f800000U; if (x < -3.40282346638528860e+38f) return 0xff800000U; if (x != x ) return 0x7fbfffffU; m = ecb_frexpf (x, &e) * 0x1000000U; r = m & 0x80000000U; if (r) m = -m; if (e <= -126) { m &= 0xffffffU; m >>= (-125 - e); e = -126; } r |= (e + 126) << 23; r |= m & 0x7fffffU; #endif return r; } /* converts an ieee single/binary32 to a float */ ecb_function_ ecb_const float ecb_binary32_to_float (uint32_t x); ecb_function_ ecb_const float ecb_binary32_to_float (uint32_t x) { float r; #if ECB_STDFP memcpy (&r, &x, 4); #else /* emulation, only works for normals and subnormals and +0 */ int neg = x >> 31; int e = (x >> 23) & 0xffU; x &= 0x7fffffU; if (e) x |= 0x800000U; else e = 1; /* we distrust ldexpf a bit and do the 2**-24 scaling by an extra multiply */ r = ecb_ldexpf (x * (0.5f / 0x800000U), e - 126); r = neg ? -r : r; #endif return r; } /* convert a double to ieee double/binary64 */ ecb_function_ ecb_const uint64_t ecb_double_to_binary64 (double x); ecb_function_ ecb_const uint64_t ecb_double_to_binary64 (double x) { uint64_t r; #if ECB_STDFP memcpy (&r, &x, 8); #else /* slow emulation, works for anything but -0 */ uint64_t m; int e; if (x == 0e0 ) return 0x0000000000000000U; if (x > +1.79769313486231470e+308) return 0x7ff0000000000000U; if (x < -1.79769313486231470e+308) return 0xfff0000000000000U; if (x != x ) return 0X7ff7ffffffffffffU; m = frexp (x, &e) * 0x20000000000000U; r = m & 0x8000000000000000;; if (r) m = -m; if (e <= -1022) { m &= 0x1fffffffffffffU; m >>= (-1021 - e); e = -1022; } r |= ((uint64_t)(e + 1022)) << 52; r |= m & 0xfffffffffffffU; #endif return r; } /* converts an ieee double/binary64 to a double */ ecb_function_ ecb_const double ecb_binary64_to_double (uint64_t x); ecb_function_ ecb_const double ecb_binary64_to_double (uint64_t x) { double r; #if ECB_STDFP memcpy (&r, &x, 8); #else /* emulation, only works for normals and subnormals and +0 */ int neg = x >> 63; int e = (x >> 52) & 0x7ffU; x &= 0xfffffffffffffU; if (e) x |= 0x10000000000000U; else e = 1; /* we distrust ldexp a bit and do the 2**-53 scaling by an extra multiply */ r = ldexp (x * (0.5 / 0x10000000000000U), e - 1022); r = neg ? -r : r; #endif return r; } /* convert a float to ieee half/binary16 */ ecb_function_ ecb_const uint16_t ecb_float_to_binary16 (float x); ecb_function_ ecb_const uint16_t ecb_float_to_binary16 (float x) { return ecb_binary32_to_binary16 (ecb_float_to_binary32 (x)); } /* convert an ieee half/binary16 to float */ ecb_function_ ecb_const float ecb_binary16_to_float (uint16_t x); ecb_function_ ecb_const float ecb_binary16_to_float (uint16_t x) { return ecb_binary32_to_float (ecb_binary16_to_binary32 (x)); } #endif #endif Async-Interrupt-1.25/README0000644000000000000000000005630513457035364014111 0ustar rootrootNAME Async::Interrupt - allow C/XS libraries to interrupt perl asynchronously SYNOPSIS use Async::Interrupt; DESCRIPTION This module implements a single feature only of interest to advanced perl modules, namely asynchronous interruptions (think "UNIX signals", which are very similar). Sometimes, modules wish to run code asynchronously (in another thread, or from a signal handler), and then signal the perl interpreter on certain events. One common way is to write some data to a pipe and use an event handling toolkit to watch for I/O events. Another way is to send a signal. Those methods are slow, and in the case of a pipe, also not asynchronous - it won't interrupt a running perl interpreter. This module implements asynchronous notifications that enable you to signal running perl code from another thread, asynchronously, and sometimes even without using a single syscall. USAGE SCENARIOS Race-free signal handling There seems to be no way to do race-free signal handling in perl: to catch a signal, you have to execute Perl code, and between entering the interpreter "select" function (or other blocking functions) and executing the select syscall is a small but relevant timespan during which signals will be queued, but perl signal handlers will not be executed and the blocking syscall will not be interrupted. You can use this module to bind a signal to a callback while at the same time activating an event pipe that you can "select" on, fixing the race completely. This can be used to implement the signal hadling in event loops, e.g. AnyEvent, POE, IO::Async::Loop and so on. Background threads want speedy reporting Assume you want very exact timing, and you can spare an extra cpu core for that. Then you can run an extra thread that signals your perl interpreter. This means you can get a very exact timing source while your perl code is number crunching, without even using a syscall to communicate between your threads. For example the deliantra game server uses a variant of this technique to interrupt background processes regularly to send map updates to game clients. Or EV::Loop::Async uses an interrupt object to wake up perl when new events have arrived. IO::AIO and BDB could also use this to speed up result reporting. Speedy event loop invocation One could use this module e.g. in Coro to interrupt a running coro-thread and cause it to enter the event loop. Or one could bind to "SIGIO" and tell some important sockets to send this signal, causing the event loop to be entered to reduce network latency. HOW TO USE You can use this module by creating an "Async::Interrupt" object for each such event source. This object stores a perl and/or a C-level callback that is invoked when the "Async::Interrupt" object gets signalled. It is executed at the next time the perl interpreter is running (i.e. it will interrupt a computation, but not an XS function or a syscall). You can signal the "Async::Interrupt" object either by calling it's "->signal" method, or, more commonly, by calling a C function. There is also the built-in (POSIX) signal source. The "->signal_func" returns the address of the C function that is to be called (plus an argument to be used during the call). The signalling function also takes an integer argument in the range SIG_ATOMIC_MIN to SIG_ATOMIC_MAX (guaranteed to allow at least 0..127). Since this kind of interruption is fast, but can only interrupt a *running* interpreter, there is optional support for signalling a pipe - that means you can also wait for the pipe to become readable (e.g. via EV or AnyEvent). This, of course, incurs the overhead of a "read" and "write" syscall. USAGE EXAMPLES Implementing race-free signal handling This example uses a single event pipe for all signals, and one Async::Interrupt per signal. This code is actually what the AnyEvent module uses itself when Async::Interrupt is available. First, create the event pipe and hook it into the event loop $SIGPIPE = new Async::Interrupt::EventPipe; $SIGPIPE_W = AnyEvent->io ( fh => $SIGPIPE->fileno, poll => "r", cb => \&_signal_check, # defined later ); Then, for each signal to hook, create an Async::Interrupt object. The callback just sets a global variable, as we are only interested in synchronous signals (i.e. when the event loop polls), which is why the pipe draining is not done automatically. my $interrupt = new Async::Interrupt cb => sub { undef $SIGNAL_RECEIVED{$signum} }, signal => $signum, pipe => [$SIGPIPE->filenos], pipe_autodrain => 0, ; Finally, the I/O callback for the event pipe handles the signals: sub _signal_check { # drain the pipe first $SIGPIPE->drain; # two loops, just to be sure while (%SIGNAL_RECEIVED) { for (keys %SIGNAL_RECEIVED) { delete $SIGNAL_RECEIVED{$_}; warn "signal $_ received\n"; } } } Interrupt perl from another thread This example interrupts the Perl interpreter from another thread, via the XS API. This is used by e.g. the EV::Loop::Async module. On the Perl level, a new loop object (which contains the thread) is created, by first calling some XS constructor, querying the C-level callback function and feeding that as the "c_cb" into the Async::Interrupt constructor: my $self = XS_thread_constructor; my ($c_func, $c_arg) = _c_func $self; # return the c callback my $asy = new Async::Interrupt c_cb => [$c_func, $c_arg]; Then the newly created Interrupt object is queried for the signaling function that the newly created thread should call, and this is in turn told to the thread object: _attach $self, $asy->signal_func; So to repeat: first the XS object is created, then it is queried for the callback that should be called when the Interrupt object gets signalled. Then the interrupt object is queried for the callback fucntion that the thread should call to signal the Interrupt object, and this callback is then attached to the thread. You have to be careful that your new thread is not signalling before the signal function was configured, for example by starting the background thread only within "_attach". That concludes the Perl part. The XS part consists of the actual constructor which creates a thread, which is not relevant for this example, and two functions, "_c_func", which returns the Perl-side callback, and "_attach", which configures the signalling functioon that is safe toc all from another thread. For simplicity, we will use global variables to store the functions, normally you would somehow attach them to $self. The "c_func" simply returns the address of a static function and arranges for the object pointed to by $self to be passed to it, as an integer: void _c_func (SV *loop) PPCODE: EXTEND (SP, 2); PUSHs (sv_2mortal (newSViv (PTR2IV (c_func)))); PUSHs (sv_2mortal (newSViv (SvRV (loop)))); This would be the callback (since it runs in a normal Perl context, it is permissible to manipulate Perl values): static void c_func (pTHX_ void *loop_, int value) { SV *loop_object = (SV *)loop_; ... } And this attaches the signalling callback: static void (*my_sig_func) (void *signal_arg, int value); static void *my_sig_arg; void _attach (SV *loop_, IV sig_func, void *sig_arg) CODE: { my_sig_func = sig_func; my_sig_arg = sig_arg; /* now run the thread */ thread_create (&u->tid, l_run, 0); } And "l_run" (the background thread) would eventually call the signaling function: my_sig_func (my_sig_arg, 0); You can have a look at EV::Loop::Async for an actual example using intra-thread communication, locking and so on. THE Async::Interrupt CLASS $async = new Async::Interrupt key => value... Creates a new Async::Interrupt object. You may only use async notifications on this object while it exists, so you need to keep a reference to it at all times while it is used. Optional constructor arguments include (normally you would specify at least one of "cb" or "c_cb"). cb => $coderef->($value) Registers a perl callback to be invoked whenever the async interrupt is signalled. Note that, since this callback can be invoked at basically any time, it must not modify any well-known global variables such as $/ without restoring them again before returning. The exceptions are $! and $@, which are saved and restored by Async::Interrupt. If the callback should throw an exception, then it will be caught, and $Async::Interrupt::DIED will be called with $@ containing the exception. The default will simply "warn" about the message and continue. c_cb => [$c_func, $c_arg] Registers a C callback the be invoked whenever the async interrupt is signalled. The C callback must have the following prototype: void c_func (pTHX_ void *c_arg, int value); Both $c_func and $c_arg must be specified as integers/IVs, and $value is the "value" passed to some earlier call to either $signal or the "signal_func" function. Note that, because the callback can be invoked at almost any time, you have to be careful at saving and restoring global variables that Perl might use (the exception is "errno", which is saved and restored by Async::Interrupt). The callback itself runs as part of the perl context, so you can call any perl functions and modify any perl data structures (in which case the requirements set out for "cb" apply as well). var => $scalar_ref When specified, then the given argument must be a reference to a scalar. The scalar will be set to 0 initially. Signalling the interrupt object will set it to the passed value, handling the interrupt will reset it to 0 again. Note that the only thing you are legally allowed to do is to is to check the variable in a boolean or integer context (e.g. comparing it with a string, or printing it, will *destroy* it and might cause your program to crash or worse). signal => $signame_or_value When this parameter is specified, then the Async::Interrupt will hook the given signal, that is, it will effectively call "->signal (0)" each time the given signal is caught by the process. Only one async can hook a given signal, and the signal will be restored to defaults when the Async::Interrupt object gets destroyed. signal_hysteresis => $boolean Sets the initial signal hysteresis state, see the "signal_hysteresis" method, below. pipe => [$fileno_or_fh_for_reading, $fileno_or_fh_for_writing] Specifies two file descriptors (or file handles) that should be signalled whenever the async interrupt is signalled. This means a single octet will be written to it, and before the callback is being invoked, it will be read again. Due to races, it is unlikely but possible that multiple octets are written. It is required that the file handles are both in nonblocking mode. The object will keep a reference to the file handles. This can be used to ensure that async notifications will interrupt event frameworks as well. Note that "Async::Interrupt" will create a suitable signal fd automatically when your program requests one, so you don't have to specify this argument when all you want is an extra file descriptor to watch. If you want to share a single event pipe between multiple Async::Interrupt objects, you can use the "Async::Interrupt::EventPipe" class to manage those. pipe_autodrain => $boolean Sets the initial autodrain state, see the "pipe_autodrain" method, below. ($signal_func, $signal_arg) = $async->signal_func Returns the address of a function to call asynchronously. The function has the following prototype and needs to be passed the specified $signal_arg, which is a "void *" cast to "IV": void (*signal_func) (void *signal_arg, int value) An example call would look like: signal_func (signal_arg, 0); The function is safe to call from within signal and thread contexts, at any time. The specified "value" is passed to both C and Perl callback. $value must be in the valid range for a "sig_atomic_t", except 0 (1..127 is portable). If the function is called while the Async::Interrupt object is already signaled but before the callbacks are being executed, then the stored "value" is either the old or the new one. Due to the asynchronous nature of the code, the "value" can even be passed to two consecutive invocations of the callback. $address = $async->c_var Returns the address (cast to IV) of an "IV" variable. The variable is set to 0 initially and gets set to the passed value whenever the object gets signalled, and reset to 0 once the interrupt has been handled. Note that it is often beneficial to just call "PERL_ASYNC_CHECK ()" to handle any interrupts. Example: call some XS function to store the address, then show C code waiting for it. my_xs_func $async->c_var; static IV *valuep; void my_xs_func (void *addr) CODE: valuep = (IV *)addr; // code in a loop, waiting while (!*valuep) ; // do something $async->signal ($value=1) This signals the given async object from Perl code. Semi-obviously, this will instantly trigger the callback invocation (it does not, as the name might imply, do anything with POSIX signals). $value must be in the valid range for a "sig_atomic_t", except 0 (1..127 is portable). $async->handle Calls the callback if the object is pending. This method does not need to be called normally, as it will be invoked automatically. However, it can be used to force handling of outstanding interrupts while the object is blocked. One reason why one might want to do that is when you want to switch from asynchronous interruptions to synchronous one, using e.g. an event loop. To do that, one would first "$async->block" the interrupt object, then register a read watcher on the "pipe_fileno" that calls "$async->handle". This disables asynchronous interruptions, but ensures that interrupts are handled by the event loop. $async->signal_hysteresis ($enable) Enables or disables signal hysteresis (default: disabled). If a POSIX signal is used as a signal source for the interrupt object, then enabling signal hysteresis causes Async::Interrupt to reset the signal action to "SIG_IGN" in the signal handler and restore it just before handling the interruption. When you expect a lot of signals (e.g. when using SIGIO), then enabling signal hysteresis can reduce the number of handler invocations considerably, at the cost of two extra syscalls. Note that setting the signal to "SIG_IGN" can have unintended side effects when you fork and exec other programs, as often they do not expect signals to be ignored by default. $async->block $async->unblock Sometimes you need a "critical section" of code that will not be interrupted by an Async::Interrupt. This can be implemented by calling "$async->block" before the critical section, and "$async->unblock" afterwards. Note that there must be exactly one call of "unblock" for every previous call to "block" (i.e. calls can nest). Since ensuring this in the presence of exceptions and threads is usually more difficult than you imagine, I recommend using "$async->scoped_block" instead. $async->scope_block This call "$async->block" and installs a handler that is called when the current scope is exited (via an exception, by canceling the Coro thread, by calling last/goto etc.). This is the recommended (and fastest) way to implement critical sections. ($block_func, $block_arg) = $async->scope_block_func Returns the address of a function that implements the "scope_block" functionality. It has the following prototype and needs to be passed the specified $block_arg, which is a "void *" cast to "IV": void (*block_func) (void *block_arg) An example call would look like: block_func (block_arg); The function is safe to call only from within the toplevel of a perl XS function and will call "LEAVE" and "ENTER" (in this order!). $async->pipe_enable $async->pipe_disable Enable/disable signalling the pipe when the interrupt occurs (default is enabled). Writing to a pipe is relatively expensive, so it can be disabled when you know you are not waiting for it (for example, with EV you could disable the pipe in a check watcher, and enable it in a prepare watcher). Note that currently, while "pipe_disable" is in effect, no attempt to read from the pipe will be done when handling events. This might change as soon as I realize why this is a mistake. $fileno = $async->pipe_fileno Returns the reading side of the signalling pipe. If no signalling pipe is currently attached to the object, it will dynamically create one. Note that the only valid operation on this file descriptor is to wait until it is readable. The fd might belong currently to a pipe, a tcp socket, or an eventfd, depending on the platform, and is guaranteed to be "select"able. $async->pipe_autodrain ($enable) Enables (1) or disables (0) automatic draining of the pipe (default: enabled). When automatic draining is enabled, then Async::Interrupt will automatically clear the pipe. Otherwise the user is responsible for this draining. This is useful when you want to share one pipe among many Async::Interrupt objects. $async->pipe_drain Drains the pipe manually, for example, when autodrain is disabled. Does nothing when no pipe is enabled. $async->post_fork The object will not normally be usable after a fork (as the pipe fd is shared between processes). Calling this method after a fork in the child ensures that the object will work as expected again. It only needs to be called when the async object is used in the child. This only works when the pipe was created by Async::Interrupt. Async::Interrupt ensures that the reading file descriptor does not change it's value. $signum = Async::Interrupt::sig2num $signame_or_number $signame = Async::Interrupt::sig2name $signame_or_number These two convenience functions simply convert a signal name or number to the corresponding name or number. They are not used by this module and exist just because perl doesn't have a nice way to do this on its own. They will return "undef" on illegal names or numbers. THE Async::Interrupt::EventPipe CLASS Pipes are the predominant utility to make asynchronous signals synchronous. However, pipes are hard to come by: they don't exist on the broken windows platform, and on GNU/Linux systems, you might want to use an "eventfd" instead. This class creates selectable event pipes in a portable fashion: on windows, it will try to create a tcp socket pair, on GNU/Linux, it will try to create an eventfd and everywhere else it will try to use a normal pipe. $epipe = new Async::Interrupt::EventPipe This creates and returns an eventpipe object. This object is simply a blessed array reference: ($r_fd, $w_fd) = $epipe->filenos Returns the read-side file descriptor and the write-side file descriptor. Example: pass an eventpipe object as pipe to the Async::Interrupt constructor, and create an AnyEvent watcher for the read side. my $epipe = new Async::Interrupt::EventPipe; my $asy = new Async::Interrupt pipe => [$epipe->filenos]; my $iow = AnyEvent->io (fh => $epipe->fileno, poll => 'r', cb => sub { }); $r_fd = $epipe->fileno Return only the reading/listening side. $epipe->signal Write something to the pipe, in a portable fashion. $epipe->drain Drain (empty) the pipe. ($c_func, $c_arg) = $epipe->signal_func ($c_func, $c_arg) = $epipe->drain_func These two methods returns a function pointer and "void *" argument that can be called to have the effect of "$epipe->signal" or "$epipe->drain", respectively, on the XS level. They both have the following prototype and need to be passed their $c_arg, which is a "void *" cast to an "IV": void (*c_func) (void *c_arg) An example call would look like: c_func (c_arg); $epipe->renew Recreates the pipe (usually required in the child after a fork). The reading side will not change it's file descriptor number, but the writing side might. $epipe->wait This method blocks the process until there are events on the pipe. This is not a very event-based or ncie way of usign an event pipe, but it can be occasionally useful. IMPLEMENTATION DETAILS AND LIMITATIONS This module works by "hijacking" SIGKILL, which is guaranteed to always exist, but also cannot be caught, so is always available. Basically, this module fakes the occurance of a SIGKILL signal and then intercepts the interpreter handling it. This makes normal signal handling slower (probably unmeasurably, though), but has the advantage of not requiring a special runops function, nor slowing down normal perl execution a bit. It assumes that "sig_atomic_t", "int" and "IV" are all async-safe to modify. AUTHOR Marc Lehmann http://home.schmorp.de/ Async-Interrupt-1.25/Interrupt.xs0000644000000000000000000002763713265444627015612 0ustar rootroot#include "EXTERN.h" #include "perl.h" #include "XSUB.h" #define ECB_NO_LIBM 1 #define ECB_NO_THREADS 1 #include "ecb.h" #include "schmorp.h" typedef volatile sig_atomic_t atomic_t; static int *sig_pending, *psig_pend; /* make local copies because of missing THX */ static Sighandler_t old_sighandler; static atomic_t async_pending; #define PERL_VERSION_ATLEAST(a,b,c) \ (PERL_REVISION > (a) \ || (PERL_REVISION == (a) \ && (PERL_VERSION > (b) \ || (PERL_VERSION == (b) && PERL_SUBVERSION >= (c))))) #if defined(HAS_SIGACTION) && defined(SA_SIGINFO) # define HAS_SA_SIGINFO 1 #endif #if !PERL_VERSION_ATLEAST(5,10,0) # undef HAS_SA_SIGINFO #endif /*****************************************************************************/ typedef struct { SV *cb; void (*c_cb)(pTHX_ void *c_arg, int value); void *c_arg; SV *fh_r, *fh_w; SV *value; int signum; int autodrain; ANY *scope_savestack; volatile int blocked; s_epipe ep; int fd_wlen; atomic_t fd_enable; atomic_t pending; volatile IV *valuep; atomic_t hysteresis; } async_t; static AV *asyncs; static async_t *sig_async [SIG_SIZE]; #define SvASYNC_nrv(sv) INT2PTR (async_t *, SvIVX (sv)) #define SvASYNC(rv) SvASYNC_nrv (SvRV (rv)) static void async_signal (void *signal_arg, int value); static void setsig (int signum, void (*handler)(int)) { #if _WIN32 signal (signum, handler); #else struct sigaction sa; sa.sa_handler = handler; sigfillset (&sa.sa_mask); sa.sa_flags = 0; /* if we interrupt a syscall, we might drain the pipe before it became ready */ sigaction (signum, &sa, 0); #endif } static void async_sigsend (int signum) { async_signal (sig_async [signum], 0); } /* the main workhorse to signal */ static void async_signal (void *signal_arg, int value) { static char pipedata [8]; async_t *async = (async_t *)signal_arg; int pending = async->pending; if (async->hysteresis) setsig (async->signum, SIG_IGN); *async->valuep = value ? value : 1; ECB_MEMORY_FENCE_RELEASE; async->pending = 1; ECB_MEMORY_FENCE_RELEASE; async_pending = 1; ECB_MEMORY_FENCE_RELEASE; if (!async->blocked) { psig_pend [9] = 1; ECB_MEMORY_FENCE_RELEASE; *sig_pending = 1; ECB_MEMORY_FENCE_RELEASE; } if (!pending && async->fd_enable && async->ep.len) s_epipe_signal (&async->ep); } static void handle_async (async_t *async) { int old_errno = errno; int value = *async->valuep; *async->valuep = 0; async->pending = 0; /* restore signal */ if (async->hysteresis) setsig (async->signum, async_sigsend); /* drain pipe */ if (async->fd_enable && async->ep.len && async->autodrain) s_epipe_drain (&async->ep); if (async->c_cb) { dTHX; async->c_cb (aTHX_ async->c_arg, value); } if (async->cb) { dSP; SV *saveerr = SvOK (ERRSV) ? sv_mortalcopy (ERRSV) : 0; SV *savedie = PL_diehook; PL_diehook = 0; PUSHSTACKi (PERLSI_SIGNAL); PUSHMARK (SP); XPUSHs (sv_2mortal (newSViv (value))); PUTBACK; call_sv (async->cb, G_VOID | G_DISCARD | G_EVAL); if (SvTRUE (ERRSV)) { SPAGAIN; PUSHMARK (SP); PUTBACK; call_sv (get_sv ("Async::Interrupt::DIED", 1), G_VOID | G_DISCARD | G_EVAL | G_KEEPERR); sv_setpvn (ERRSV, "", 0); } if (saveerr) sv_setsv (ERRSV, saveerr); { SV *oldhook = PL_diehook; PL_diehook = savedie; SvREFCNT_dec (oldhook); } POPSTACK; } errno = old_errno; } static void handle_asyncs (void) { int i; ECB_MEMORY_FENCE_ACQUIRE; async_pending = 0; for (i = AvFILLp (asyncs); i >= 0; --i) { SV *async_sv = AvARRAY (asyncs)[i]; async_t *async = SvASYNC_nrv (async_sv); if (async->pending && !async->blocked) { /* temporarily keep a refcount */ SvREFCNT_inc (async_sv); handle_async (async); SvREFCNT_dec (async_sv); /* the handler could have deleted any number of asyncs */ if (i > AvFILLp (asyncs)) i = AvFILLp (asyncs); } } } #if HAS_SA_SIGINFO static Signal_t async_sighandler (int signum, siginfo_t *si, void *sarg) { if (signum == 9) handle_asyncs (); else old_sighandler (signum, si, sarg); } #else static Signal_t async_sighandler (int signum) { if (signum == 9) handle_asyncs (); else old_sighandler (signum); } #endif #define block(async) ++(async)->blocked static void unblock (async_t *async) { --async->blocked; if (async->pending && !async->blocked) handle_async (async); } static void scope_block_cb (pTHX_ void *async_sv) { async_t *async = SvASYNC_nrv ((SV *)async_sv); async->scope_savestack = 0; unblock (async); SvREFCNT_dec (async_sv); } static void scope_block (SV *async_sv) { async_t *async = SvASYNC_nrv (async_sv); /* as a heuristic, we skip the scope block if we already are blocked */ /* and the existing scope block used the same savestack */ if (!async->scope_savestack || async->scope_savestack != PL_savestack) { async->scope_savestack = PL_savestack; block (async); LEAVE; /* unfortunately, perl sandwiches XS calls into ENTER/LEAVE */ SAVEDESTRUCTOR_X (scope_block_cb, (void *)SvREFCNT_inc (async_sv)); ENTER; /* unfortunately, perl sandwiches XS calls into ENTER/LEAVE */ } } MODULE = Async::Interrupt PACKAGE = Async::Interrupt BOOT: old_sighandler = PL_sighandlerp; PL_sighandlerp = async_sighandler; sig_pending = &PL_sig_pending; psig_pend = PL_psig_pend; asyncs = newAV (); CvNODEBUG_on (get_cv ("Async::Interrupt::scope_block", 0)); /* otherwise calling scope can be the debugger */ PROTOTYPES: DISABLE void _alloc (SV *cb, void *c_cb, void *c_arg, SV *fh_r, SV *fh_w, SV *signl, SV *pvalue) PPCODE: { SV *cv = SvOK (cb) ? SvREFCNT_inc (s_get_cv_croak (cb)) : 0; async_t *async; Newz (0, async, 1, async_t); XPUSHs (sv_2mortal (newSViv (PTR2IV (async)))); /* TODO: need to bless right now to ensure deallocation */ av_push (asyncs, TOPs); SvGETMAGIC (fh_r); SvGETMAGIC (fh_w); if (SvOK (fh_r) || SvOK (fh_w)) { int fd_r = s_fileno_croak (fh_r, 0); int fd_w = s_fileno_croak (fh_w, 1); async->fh_r = newSVsv (fh_r); async->fh_w = newSVsv (fh_w); async->ep.fd [0] = fd_r; async->ep.fd [1] = fd_w; async->ep.len = 1; async->fd_enable = 1; } async->value = SvROK (pvalue) ? SvREFCNT_inc_NN (SvRV (pvalue)) : NEWSV (0, 0); sv_setiv (async->value, 0); SvIOK_only (async->value); /* just to be sure */ SvREADONLY_on (async->value); async->valuep = &(SvIVX (async->value)); async->autodrain = 1; async->cb = cv; async->c_cb = c_cb; async->c_arg = c_arg; async->signum = SvOK (signl) ? s_signum_croak (signl) : 0; if (async->signum) { if (async->signum < 0) croak ("Async::Interrupt::new got passed illegal signal name or number: %s", SvPV_nolen (signl)); sig_async [async->signum] = async; setsig (async->signum, async_sigsend); } } void signal_hysteresis (async_t *async, int enable) CODE: async->hysteresis = enable; void signal_func (async_t *async) PPCODE: EXTEND (SP, 2); PUSHs (sv_2mortal (newSViv (PTR2IV (async_signal)))); PUSHs (sv_2mortal (newSViv (PTR2IV (async)))); void scope_block_func (SV *self) PPCODE: EXTEND (SP, 2); PUSHs (sv_2mortal (newSViv (PTR2IV (scope_block)))); PUSHs (sv_2mortal (newSViv (PTR2IV (SvRV (self))))); IV c_var (async_t *async) CODE: RETVAL = PTR2IV (async->valuep); OUTPUT: RETVAL void handle (async_t *async) CODE: handle_async (async); void signal (async_t *async, int value = 1) CODE: async_signal (async, value); void block (async_t *async) CODE: block (async); void unblock (async_t *async) CODE: unblock (async); void scope_block (SV *self) CODE: scope_block (SvRV (self)); void pipe_enable (async_t *async) ALIAS: pipe_enable = 1 pipe_disable = 0 CODE: async->fd_enable = ix; int pipe_fileno (async_t *async) CODE: if (!async->ep.len) { int res; /*block (async);*//*TODO*/ res = s_epipe_new (&async->ep); async->fd_enable = 1; /*unblock (async);*//*TODO*/ if (res < 0) croak ("Async::Interrupt: unable to initialize event pipe"); } RETVAL = async->ep.fd [0]; OUTPUT: RETVAL int pipe_autodrain (async_t *async, int enable = -1) CODE: RETVAL = async->autodrain; if (enable >= 0) async->autodrain = enable; OUTPUT: RETVAL void pipe_drain (async_t *async) CODE: if (async->ep.len) s_epipe_drain (&async->ep); void post_fork (async_t *async) CODE: if (async->ep.len) { int res; /*block (async);*//*TODO*/ res = s_epipe_renew (&async->ep); /*unblock (async);*//*TODO*/ if (res < 0) croak ("Async::Interrupt: unable to initialize event pipe after fork"); } void DESTROY (SV *self) CODE: { int i; SV *async_sv = SvRV (self); async_t *async = SvASYNC_nrv (async_sv); for (i = AvFILLp (asyncs); i >= 0; --i) if (AvARRAY (asyncs)[i] == async_sv) { AvARRAY (asyncs)[i] = AvARRAY (asyncs)[AvFILLp (asyncs)]; av_pop (asyncs); goto found; } if (!PL_dirty) warn ("Async::Interrupt::DESTROY could not find async object in list of asyncs, please report"); found: if (async->signum) setsig (async->signum, SIG_DFL); if (!async->fh_r && async->ep.len) s_epipe_destroy (&async->ep); SvREFCNT_dec (async->fh_r); SvREFCNT_dec (async->fh_w); SvREFCNT_dec (async->cb); SvREFCNT_dec (async->value); Safefree (async); } SV * sig2num (SV *signame_or_number) ALIAS: sig2num = 0 sig2name = 1 PROTOTYPE: $ CODE: { int signum = s_signum (signame_or_number); if (signum < 0) RETVAL = &PL_sv_undef; else if (ix) RETVAL = newSVpv (PL_sig_name [signum], 0); else RETVAL = newSViv (signum); } OUTPUT: RETVAL MODULE = Async::Interrupt PACKAGE = Async::Interrupt::EventPipe PREFIX = s_epipe_ void new (const char *klass) PPCODE: { s_epipe *epp; Newz (0, epp, 1, s_epipe); XPUSHs (sv_setref_iv (sv_newmortal (), klass, PTR2IV (epp))); if (s_epipe_new (epp) < 0) croak ("Async::Interrupt::EventPipe: unable to create new event pipe"); } void filenos (s_epipe *epp) PPCODE: EXTEND (SP, 2); PUSHs (sv_2mortal (newSViv (epp->fd [0]))); PUSHs (sv_2mortal (newSViv (epp->fd [1]))); int fileno (s_epipe *epp) ALIAS: fileno = 0 fileno_r = 0 fileno_w = 1 CODE: RETVAL = epp->fd [ix]; OUTPUT: RETVAL int type (s_epipe *epp) CODE: RETVAL = epp->len; OUTPUT: RETVAL void s_epipe_signal (s_epipe *epp) void s_epipe_drain (s_epipe *epp) void signal_func (s_epipe *epp) ALIAS: drain_func = 1 PPCODE: EXTEND (SP, 2); PUSHs (sv_2mortal (newSViv (PTR2IV (ix ? s_epipe_drain : s_epipe_signal)))); PUSHs (sv_2mortal (newSViv (PTR2IV (epp)))); void s_epipe_wait (s_epipe *epp) void s_epipe_renew (s_epipe *epp) void DESTROY (s_epipe *epp) CODE: s_epipe_destroy (epp); Async-Interrupt-1.25/COPYING0000644000000000000000000000007610431374667014257 0ustar rootrootThis module is licensed under the same terms as perl itself. Async-Interrupt-1.25/Interrupt.pm0000644000000000000000000005326613456573632015572 0ustar rootroot=head1 NAME Async::Interrupt - allow C/XS libraries to interrupt perl asynchronously =head1 SYNOPSIS use Async::Interrupt; =head1 DESCRIPTION This module implements a single feature only of interest to advanced perl modules, namely asynchronous interruptions (think "UNIX signals", which are very similar). Sometimes, modules wish to run code asynchronously (in another thread, or from a signal handler), and then signal the perl interpreter on certain events. One common way is to write some data to a pipe and use an event handling toolkit to watch for I/O events. Another way is to send a signal. Those methods are slow, and in the case of a pipe, also not asynchronous - it won't interrupt a running perl interpreter. This module implements asynchronous notifications that enable you to signal running perl code from another thread, asynchronously, and sometimes even without using a single syscall. =head2 USAGE SCENARIOS =over 4 =item Race-free signal handling There seems to be no way to do race-free signal handling in perl: to catch a signal, you have to execute Perl code, and between entering the interpreter C on, fixing the race completely. This can be used to implement the signal hadling in event loops, e.g. L, L, L and so on. =item Background threads want speedy reporting Assume you want very exact timing, and you can spare an extra cpu core for that. Then you can run an extra thread that signals your perl interpreter. This means you can get a very exact timing source while your perl code is number crunching, without even using a syscall to communicate between your threads. For example the deliantra game server uses a variant of this technique to interrupt background processes regularly to send map updates to game clients. Or L uses an interrupt object to wake up perl when new events have arrived. L and L could also use this to speed up result reporting. =item Speedy event loop invocation One could use this module e.g. in L to interrupt a running coro-thread and cause it to enter the event loop. Or one could bind to C and tell some important sockets to send this signal, causing the event loop to be entered to reduce network latency. =back =head2 HOW TO USE You can use this module by creating an C object for each such event source. This object stores a perl and/or a C-level callback that is invoked when the C object gets signalled. It is executed at the next time the perl interpreter is running (i.e. it will interrupt a computation, but not an XS function or a syscall). You can signal the C object either by calling it's C<< ->signal >> method, or, more commonly, by calling a C function. There is also the built-in (POSIX) signal source. The C<< ->signal_func >> returns the address of the C function that is to be called (plus an argument to be used during the call). The signalling function also takes an integer argument in the range SIG_ATOMIC_MIN to SIG_ATOMIC_MAX (guaranteed to allow at least 0..127). Since this kind of interruption is fast, but can only interrupt a I interpreter, there is optional support for signalling a pipe - that means you can also wait for the pipe to become readable (e.g. via L or L). This, of course, incurs the overhead of a C and C syscall. =head1 USAGE EXAMPLES =head2 Implementing race-free signal handling This example uses a single event pipe for all signals, and one Async::Interrupt per signal. This code is actually what the L module uses itself when Async::Interrupt is available. First, create the event pipe and hook it into the event loop $SIGPIPE = new Async::Interrupt::EventPipe; $SIGPIPE_W = AnyEvent->io ( fh => $SIGPIPE->fileno, poll => "r", cb => \&_signal_check, # defined later ); Then, for each signal to hook, create an Async::Interrupt object. The callback just sets a global variable, as we are only interested in synchronous signals (i.e. when the event loop polls), which is why the pipe draining is not done automatically. my $interrupt = new Async::Interrupt cb => sub { undef $SIGNAL_RECEIVED{$signum} }, signal => $signum, pipe => [$SIGPIPE->filenos], pipe_autodrain => 0, ; Finally, the I/O callback for the event pipe handles the signals: sub _signal_check { # drain the pipe first $SIGPIPE->drain; # two loops, just to be sure while (%SIGNAL_RECEIVED) { for (keys %SIGNAL_RECEIVED) { delete $SIGNAL_RECEIVED{$_}; warn "signal $_ received\n"; } } } =head2 Interrupt perl from another thread This example interrupts the Perl interpreter from another thread, via the XS API. This is used by e.g. the L module. On the Perl level, a new loop object (which contains the thread) is created, by first calling some XS constructor, querying the C-level callback function and feeding that as the C into the Async::Interrupt constructor: my $self = XS_thread_constructor; my ($c_func, $c_arg) = _c_func $self; # return the c callback my $asy = new Async::Interrupt c_cb => [$c_func, $c_arg]; Then the newly created Interrupt object is queried for the signaling function that the newly created thread should call, and this is in turn told to the thread object: _attach $self, $asy->signal_func; So to repeat: first the XS object is created, then it is queried for the callback that should be called when the Interrupt object gets signalled. Then the interrupt object is queried for the callback fucntion that the thread should call to signal the Interrupt object, and this callback is then attached to the thread. You have to be careful that your new thread is not signalling before the signal function was configured, for example by starting the background thread only within C<_attach>. That concludes the Perl part. The XS part consists of the actual constructor which creates a thread, which is not relevant for this example, and two functions, C<_c_func>, which returns the Perl-side callback, and C<_attach>, which configures the signalling functioon that is safe toc all from another thread. For simplicity, we will use global variables to store the functions, normally you would somehow attach them to C<$self>. The C simply returns the address of a static function and arranges for the object pointed to by C<$self> to be passed to it, as an integer: void _c_func (SV *loop) PPCODE: EXTEND (SP, 2); PUSHs (sv_2mortal (newSViv (PTR2IV (c_func)))); PUSHs (sv_2mortal (newSViv (SvRV (loop)))); This would be the callback (since it runs in a normal Perl context, it is permissible to manipulate Perl values): static void c_func (pTHX_ void *loop_, int value) { SV *loop_object = (SV *)loop_; ... } And this attaches the signalling callback: static void (*my_sig_func) (void *signal_arg, int value); static void *my_sig_arg; void _attach (SV *loop_, IV sig_func, void *sig_arg) CODE: { my_sig_func = sig_func; my_sig_arg = sig_arg; /* now run the thread */ thread_create (&u->tid, l_run, 0); } And C (the background thread) would eventually call the signaling function: my_sig_func (my_sig_arg, 0); You can have a look at L for an actual example using intra-thread communication, locking and so on. =head1 THE Async::Interrupt CLASS =over 4 =cut package Async::Interrupt; use common::sense; BEGIN { # the next line forces initialisation of internal # signal handling variables, otherwise, PL_sig_pending # etc. might be null pointers. $SIG{KILL} = sub { }; our $VERSION = 1.25; require XSLoader; XSLoader::load ("Async::Interrupt", $VERSION); } our $DIED = sub { warn "$@" }; =item $async = new Async::Interrupt key => value... Creates a new Async::Interrupt object. You may only use async notifications on this object while it exists, so you need to keep a reference to it at all times while it is used. Optional constructor arguments include (normally you would specify at least one of C or C). =over 4 =item cb => $coderef->($value) Registers a perl callback to be invoked whenever the async interrupt is signalled. Note that, since this callback can be invoked at basically any time, it must not modify any well-known global variables such as C<$/> without restoring them again before returning. The exceptions are C<$!> and C<$@>, which are saved and restored by Async::Interrupt. If the callback should throw an exception, then it will be caught, and C<$Async::Interrupt::DIED> will be called with C<$@> containing the exception. The default will simply C about the message and continue. =item c_cb => [$c_func, $c_arg] Registers a C callback the be invoked whenever the async interrupt is signalled. The C callback must have the following prototype: void c_func (pTHX_ void *c_arg, int value); Both C<$c_func> and C<$c_arg> must be specified as integers/IVs, and C<$value> is the C passed to some earlier call to either C<$signal> or the C function. Note that, because the callback can be invoked at almost any time, you have to be careful at saving and restoring global variables that Perl might use (the exception is C, which is saved and restored by Async::Interrupt). The callback itself runs as part of the perl context, so you can call any perl functions and modify any perl data structures (in which case the requirements set out for C apply as well). =item var => $scalar_ref When specified, then the given argument must be a reference to a scalar. The scalar will be set to C<0> initially. Signalling the interrupt object will set it to the passed value, handling the interrupt will reset it to C<0> again. Note that the only thing you are legally allowed to do is to is to check the variable in a boolean or integer context (e.g. comparing it with a string, or printing it, will I it and might cause your program to crash or worse). =item signal => $signame_or_value When this parameter is specified, then the Async::Interrupt will hook the given signal, that is, it will effectively call C<< ->signal (0) >> each time the given signal is caught by the process. Only one async can hook a given signal, and the signal will be restored to defaults when the Async::Interrupt object gets destroyed. =item signal_hysteresis => $boolean Sets the initial signal hysteresis state, see the C method, below. =item pipe => [$fileno_or_fh_for_reading, $fileno_or_fh_for_writing] Specifies two file descriptors (or file handles) that should be signalled whenever the async interrupt is signalled. This means a single octet will be written to it, and before the callback is being invoked, it will be read again. Due to races, it is unlikely but possible that multiple octets are written. It is required that the file handles are both in nonblocking mode. The object will keep a reference to the file handles. This can be used to ensure that async notifications will interrupt event frameworks as well. Note that C will create a suitable signal fd automatically when your program requests one, so you don't have to specify this argument when all you want is an extra file descriptor to watch. If you want to share a single event pipe between multiple Async::Interrupt objects, you can use the C class to manage those. =item pipe_autodrain => $boolean Sets the initial autodrain state, see the C method, below. =back =cut sub new { my ($class, %arg) = @_; my $self = bless \(_alloc $arg{cb}, @{$arg{c_cb}}[0,1], @{$arg{pipe}}[0,1], $arg{signal}, $arg{var}), $class; # urgs, reminds me of Event for my $attr (qw(pipe_autodrain signal_hysteresis)) { $self->$attr ($arg{$attr}) if exists $arg{$attr}; } $self } =item ($signal_func, $signal_arg) = $async->signal_func Returns the address of a function to call asynchronously. The function has the following prototype and needs to be passed the specified C<$signal_arg>, which is a C cast to C: void (*signal_func) (void *signal_arg, int value) An example call would look like: signal_func (signal_arg, 0); The function is safe to call from within signal and thread contexts, at any time. The specified C is passed to both C and Perl callback. C<$value> must be in the valid range for a C, except C<0> (1..127 is portable). If the function is called while the Async::Interrupt object is already signaled but before the callbacks are being executed, then the stored C is either the old or the new one. Due to the asynchronous nature of the code, the C can even be passed to two consecutive invocations of the callback. =item $address = $async->c_var Returns the address (cast to IV) of an C variable. The variable is set to C<0> initially and gets set to the passed value whenever the object gets signalled, and reset to C<0> once the interrupt has been handled. Note that it is often beneficial to just call C to handle any interrupts. Example: call some XS function to store the address, then show C code waiting for it. my_xs_func $async->c_var; static IV *valuep; void my_xs_func (void *addr) CODE: valuep = (IV *)addr; // code in a loop, waiting while (!*valuep) ; // do something =item $async->signal ($value=1) This signals the given async object from Perl code. Semi-obviously, this will instantly trigger the callback invocation (it does not, as the name might imply, do anything with POSIX signals). C<$value> must be in the valid range for a C, except C<0> (1..127 is portable). =item $async->handle Calls the callback if the object is pending. This method does not need to be called normally, as it will be invoked automatically. However, it can be used to force handling of outstanding interrupts while the object is blocked. One reason why one might want to do that is when you want to switch from asynchronous interruptions to synchronous one, using e.g. an event loop. To do that, one would first C<< $async->block >> the interrupt object, then register a read watcher on the C that calls C<< $async->handle >>. This disables asynchronous interruptions, but ensures that interrupts are handled by the event loop. =item $async->signal_hysteresis ($enable) Enables or disables signal hysteresis (default: disabled). If a POSIX signal is used as a signal source for the interrupt object, then enabling signal hysteresis causes Async::Interrupt to reset the signal action to C in the signal handler and restore it just before handling the interruption. When you expect a lot of signals (e.g. when using SIGIO), then enabling signal hysteresis can reduce the number of handler invocations considerably, at the cost of two extra syscalls. Note that setting the signal to C can have unintended side effects when you fork and exec other programs, as often they do not expect signals to be ignored by default. =item $async->block =item $async->unblock Sometimes you need a "critical section" of code that will not be interrupted by an Async::Interrupt. This can be implemented by calling C<< $async->block >> before the critical section, and C<< $async->unblock >> afterwards. Note that there must be exactly one call of C for every previous call to C (i.e. calls can nest). Since ensuring this in the presence of exceptions and threads is usually more difficult than you imagine, I recommend using C<< $async->scoped_block >> instead. =item $async->scope_block This call C<< $async->block >> and installs a handler that is called when the current scope is exited (via an exception, by canceling the Coro thread, by calling last/goto etc.). This is the recommended (and fastest) way to implement critical sections. =item ($block_func, $block_arg) = $async->scope_block_func Returns the address of a function that implements the C functionality. It has the following prototype and needs to be passed the specified C<$block_arg>, which is a C cast to C: void (*block_func) (void *block_arg) An example call would look like: block_func (block_arg); The function is safe to call only from within the toplevel of a perl XS function and will call C and C (in this order!). =item $async->pipe_enable =item $async->pipe_disable Enable/disable signalling the pipe when the interrupt occurs (default is enabled). Writing to a pipe is relatively expensive, so it can be disabled when you know you are not waiting for it (for example, with L you could disable the pipe in a check watcher, and enable it in a prepare watcher). Note that currently, while C is in effect, no attempt to read from the pipe will be done when handling events. This might change as soon as I realize why this is a mistake. =item $fileno = $async->pipe_fileno Returns the reading side of the signalling pipe. If no signalling pipe is currently attached to the object, it will dynamically create one. Note that the only valid operation on this file descriptor is to wait until it is readable. The fd might belong currently to a pipe, a tcp socket, or an eventfd, depending on the platform, and is guaranteed to be C