diff options
Diffstat (limited to 'lib/PublicInbox/Syscall.pm')
-rw-r--r-- | lib/PublicInbox/Syscall.pm | 576 |
1 files changed, 391 insertions, 185 deletions
diff --git a/lib/PublicInbox/Syscall.pm b/lib/PublicInbox/Syscall.pm index c00385b9..4cbe9623 100644 --- a/lib/PublicInbox/Syscall.pm +++ b/lib/PublicInbox/Syscall.pm @@ -2,34 +2,34 @@ # specifically the Debian libsys-syscall-perl 0.25-6 version to # fix upstream regressions in 0.25. # +# See devel/sysdefs-list in the public-inbox source tree for maintenance +# <https://80x24.org/public-inbox.git>, and machines from the GCC Farm: +# <https://portal.cfarm.net/> +# # This license differs from the rest of public-inbox # # This module is Copyright (c) 2005 Six Apart, Ltd. -# Copyright (C) 2019-2021 all contributors <meta@public-inbox.org> +# Copyright (C) all contributors <meta@public-inbox.org> # # All rights reserved. # # You may distribute under the terms of either the GNU General Public # License or the Artistic License, as specified in the Perl README file. package PublicInbox::Syscall; -use strict; -use v5.10.1; +use v5.12; use parent qw(Exporter); -use POSIX qw(ENOENT EEXIST ENOSYS O_NONBLOCK); +use POSIX qw(ENOENT ENOSYS EINVAL O_NONBLOCK); +use Socket qw(SOL_SOCKET SCM_RIGHTS); use Config; +our %SIGNUM = (WINCH => 28); # most Linux, {Free,Net,Open}BSD, *Darwin +our ($INOTIFY, %PACK); # $VERSION = '0.25'; # Sys::Syscall version our @EXPORT_OK = qw(epoll_ctl epoll_create epoll_wait - EPOLLIN EPOLLOUT EPOLLET - EPOLL_CTL_ADD EPOLL_CTL_DEL EPOLL_CTL_MOD - EPOLLONESHOT EPOLLEXCLUSIVE - signalfd rename_noreplace); -our %EXPORT_TAGS = (epoll => [qw(epoll_ctl epoll_create epoll_wait - EPOLLIN EPOLLOUT - EPOLL_CTL_ADD EPOLL_CTL_DEL EPOLL_CTL_MOD - EPOLLONESHOT EPOLLEXCLUSIVE)], - ); - + EPOLLIN EPOLLOUT EPOLLET + EPOLL_CTL_ADD EPOLL_CTL_DEL EPOLL_CTL_MOD + EPOLLONESHOT EPOLLEXCLUSIVE + signalfd rename_noreplace %SIGNUM $F_SETPIPE_SZ); use constant { EPOLLIN => 1, EPOLLOUT => 4, @@ -42,182 +42,289 @@ use constant { EPOLL_CTL_ADD => 1, EPOLL_CTL_DEL => 2, EPOLL_CTL_MOD => 3, + SIZEOF_int => $Config{intsize}, + SIZEOF_size_t => $Config{sizesize}, + SIZEOF_ptr => $Config{ptrsize}, + NUL => "\0", }; -our $loaded_syscall = 0; - -sub _load_syscall { - # props to Gaal for this! - return if $loaded_syscall++; - my $clean = sub { - delete @INC{qw<syscall.ph asm/unistd.ph bits/syscall.ph - _h2ph_pre.ph sys/syscall.ph>}; - }; - $clean->(); # don't trust modules before us - my $rv = eval { require 'syscall.ph'; 1 } || eval { require 'sys/syscall.ph'; 1 }; - $clean->(); # don't require modules after us trust us - $rv; -} - +use constant TMPL_size_t => SIZEOF_size_t == 8 ? 'Q' : 'L'; -our ( - $SYS_epoll_create, - $SYS_epoll_ctl, - $SYS_epoll_wait, - $SYS_signalfd4, - $SYS_renameat2, - ); +our ($SYS_epoll_create, + $SYS_epoll_ctl, + $SYS_epoll_wait, + $SYS_signalfd4, + $SYS_renameat2, + $F_SETPIPE_SZ, + $SYS_sendmsg, + $SYS_recvmsg); +my $SYS_fstatfs; # don't need fstatfs64, just statfs.f_type +my ($FS_IOC_GETFLAGS, $FS_IOC_SETFLAGS); my $SFD_CLOEXEC = 02000000; # Perl does not expose O_CLOEXEC our $no_deprecated = 0; if ($^O eq "linux") { - my (undef, undef, $release, undef, $machine) = POSIX::uname(); - my ($maj, $min) = ($release =~ /\A([0-9]+)\.([0-9]+)/); - $SYS_renameat2 = 0 if "$maj.$min" < 3.15; - # whether the machine requires 64-bit numbers to be on 8-byte - # boundaries. - my $u64_mod_8 = 0; - - # if we're running on an x86_64 kernel, but a 32-bit process, - # we need to use the x32 or i386 syscall numbers. - if ($machine eq "x86_64" && $Config{ptrsize} == 4) { - $machine = $Config{cppsymbols} =~ /\b__ILP32__=1\b/ ? 'x32' : 'i386'; - } + $F_SETPIPE_SZ = 1031; + my (undef, undef, $release, undef, $machine) = POSIX::uname(); + my ($maj, $min) = ($release =~ /\A([0-9]+)\.([0-9]+)/); + $SYS_renameat2 = 0 if "$maj.$min" < 3.15; + # whether the machine requires 64-bit numbers to be on 8-byte + # boundaries. + my $u64_mod_8 = 0; - # Similarly for mips64 vs mips - if ($machine eq "mips64" && $Config{ptrsize} == 4) { - $machine = "mips"; - } - - if ($machine =~ m/^i[3456]86$/) { - $SYS_epoll_create = 254; - $SYS_epoll_ctl = 255; - $SYS_epoll_wait = 256; - $SYS_signalfd4 = 327; - $SYS_renameat2 //= 353; - } elsif ($machine eq "x86_64") { - $SYS_epoll_create = 213; - $SYS_epoll_ctl = 233; - $SYS_epoll_wait = 232; - $SYS_signalfd4 = 289; - $SYS_renameat2 //= 316; - } elsif ($machine eq 'x32') { - $SYS_epoll_create = 1073742037; - $SYS_epoll_ctl = 1073742057; - $SYS_epoll_wait = 1073742056; - $SYS_signalfd4 = 1073742113; - $SYS_renameat2 //= 0x40000000 + 316; - } elsif ($machine eq 'sparc64') { - $SYS_epoll_create = 193; - $SYS_epoll_ctl = 194; - $SYS_epoll_wait = 195; - $u64_mod_8 = 1; - $SYS_signalfd4 = 317; - $SYS_renameat2 //= 345; - $SFD_CLOEXEC = 020000000; - } elsif ($machine =~ m/^parisc/) { - $SYS_epoll_create = 224; - $SYS_epoll_ctl = 225; - $SYS_epoll_wait = 226; - $u64_mod_8 = 1; - $SYS_signalfd4 = 309; - } elsif ($machine =~ m/^ppc64/) { - $SYS_epoll_create = 236; - $SYS_epoll_ctl = 237; - $SYS_epoll_wait = 238; - $u64_mod_8 = 1; - $SYS_signalfd4 = 313; - $SYS_renameat2 //= 357; - } elsif ($machine eq "ppc") { - $SYS_epoll_create = 236; - $SYS_epoll_ctl = 237; - $SYS_epoll_wait = 238; - $u64_mod_8 = 1; - $SYS_signalfd4 = 313; - $SYS_renameat2 //= 357; - } elsif ($machine =~ m/^s390/) { - $SYS_epoll_create = 249; - $SYS_epoll_ctl = 250; - $SYS_epoll_wait = 251; - $u64_mod_8 = 1; - $SYS_signalfd4 = 322; - $SYS_renameat2 //= 347; - } elsif ($machine eq "ia64") { - $SYS_epoll_create = 1243; - $SYS_epoll_ctl = 1244; - $SYS_epoll_wait = 1245; - $u64_mod_8 = 1; - $SYS_signalfd4 = 289; - } elsif ($machine eq "alpha") { - # natural alignment, ints are 32-bits - $SYS_epoll_create = 407; - $SYS_epoll_ctl = 408; - $SYS_epoll_wait = 409; - $u64_mod_8 = 1; - $SYS_signalfd4 = 484; - $SFD_CLOEXEC = 010000000; - } elsif ($machine eq "aarch64") { - $SYS_epoll_create = 20; # (sys_epoll_create1) - $SYS_epoll_ctl = 21; - $SYS_epoll_wait = 22; # (sys_epoll_pwait) - $u64_mod_8 = 1; - $no_deprecated = 1; - $SYS_signalfd4 = 74; - $SYS_renameat2 //= 276; - } elsif ($machine =~ m/arm(v\d+)?.*l/) { - # ARM OABI - $SYS_epoll_create = 250; - $SYS_epoll_ctl = 251; - $SYS_epoll_wait = 252; - $u64_mod_8 = 1; - $SYS_signalfd4 = 355; - $SYS_renameat2 //= 382; - } elsif ($machine =~ m/^mips64/) { - $SYS_epoll_create = 5207; - $SYS_epoll_ctl = 5208; - $SYS_epoll_wait = 5209; - $u64_mod_8 = 1; - $SYS_signalfd4 = 5283; - $SYS_renameat2 //= 5311; - } elsif ($machine =~ m/^mips/) { - $SYS_epoll_create = 4248; - $SYS_epoll_ctl = 4249; - $SYS_epoll_wait = 4250; - $u64_mod_8 = 1; - $SYS_signalfd4 = 4324; - $SYS_renameat2 //= 4351; - } else { - # as a last resort, try using the *.ph files which may not - # exist or may be wrong - _load_syscall(); - $SYS_epoll_create = eval { &SYS_epoll_create; } || 0; - $SYS_epoll_ctl = eval { &SYS_epoll_ctl; } || 0; - $SYS_epoll_wait = eval { &SYS_epoll_wait; } || 0; + if (SIZEOF_ptr == 4) { + # if we're running on an x86_64 kernel, but a 32-bit process, + # we need to use the x32 or i386 syscall numbers. + if ($machine eq 'x86_64') { + my $s = $Config{cppsymbols}; + $machine = ($s =~ /\b__ILP32__=1\b/ && + $s =~ /\b__x86_64__=1\b/) ? + 'x32' : 'i386' + } elsif ($machine eq 'mips64') { # similarly for mips64 vs mips + $machine = 'mips'; + } + } + if ($machine =~ m/^i[3456]86$/) { + $SYS_epoll_create = 254; + $SYS_epoll_ctl = 255; + $SYS_epoll_wait = 256; + $SYS_signalfd4 = 327; + $SYS_renameat2 //= 353; + $SYS_fstatfs = 100; + $SYS_sendmsg = 370; + $SYS_recvmsg = 372; + $INOTIFY = { # usage: `use constant $PublicInbox::Syscall::INOTIFY' + SYS_inotify_init1 => 332, + SYS_inotify_add_watch => 292, + SYS_inotify_rm_watch => 293, + }; + $FS_IOC_GETFLAGS = 0x80046601; + $FS_IOC_SETFLAGS = 0x40046602; + } elsif ($machine eq "x86_64") { + $SYS_epoll_create = 213; + $SYS_epoll_ctl = 233; + $SYS_epoll_wait = 232; + $SYS_signalfd4 = 289; + $SYS_renameat2 //= 316; + $SYS_fstatfs = 138; + $SYS_sendmsg = 46; + $SYS_recvmsg = 47; + $INOTIFY = { + SYS_inotify_init1 => 294, + SYS_inotify_add_watch => 254, + SYS_inotify_rm_watch => 255, + }; + $FS_IOC_GETFLAGS = 0x80086601; + $FS_IOC_SETFLAGS = 0x40086602; + } elsif ($machine eq 'x32') { + $SYS_epoll_create = 1073742037; + $SYS_epoll_ctl = 1073742057; + $SYS_epoll_wait = 1073742056; + $SYS_signalfd4 = 1073742113; + $SYS_renameat2 //= 0x40000000 + 316; + $SYS_fstatfs = 138; + $SYS_sendmsg = 0x40000206; + $SYS_recvmsg = 0x40000207; + $FS_IOC_GETFLAGS = 0x80046601; + $FS_IOC_SETFLAGS = 0x40046602; + $INOTIFY = { + SYS_inotify_init1 => 1073742118, + SYS_inotify_add_watch => 1073742078, + SYS_inotify_rm_watch => 1073742079, + }; + } elsif ($machine eq 'sparc64') { + $SYS_epoll_create = 193; + $SYS_epoll_ctl = 194; + $SYS_epoll_wait = 195; + $u64_mod_8 = 1; + $SYS_signalfd4 = 317; + $SYS_renameat2 //= 345; + $SFD_CLOEXEC = 020000000; + $SYS_fstatfs = 158; + $SYS_sendmsg = 114; + $SYS_recvmsg = 113; + $FS_IOC_GETFLAGS = 0x40086601; + $FS_IOC_SETFLAGS = 0x80086602; + } elsif ($machine =~ m/^parisc/) { # untested, no machine on cfarm + $SYS_epoll_create = 224; + $SYS_epoll_ctl = 225; + $SYS_epoll_wait = 226; + $u64_mod_8 = 1; + $SYS_signalfd4 = 309; + $SIGNUM{WINCH} = 23; + } elsif ($machine =~ m/^ppc64/) { + $SYS_epoll_create = 236; + $SYS_epoll_ctl = 237; + $SYS_epoll_wait = 238; + $u64_mod_8 = 1; + $SYS_signalfd4 = 313; + $SYS_renameat2 //= 357; + $SYS_fstatfs = 100; + $SYS_sendmsg = 341; + $SYS_recvmsg = 342; + $FS_IOC_GETFLAGS = 0x40086601; + $FS_IOC_SETFLAGS = 0x80086602; + $INOTIFY = { + SYS_inotify_init1 => 318, + SYS_inotify_add_watch => 276, + SYS_inotify_rm_watch => 277, + }; + } elsif ($machine eq "ppc") { # untested, no machine on cfarm + $SYS_epoll_create = 236; + $SYS_epoll_ctl = 237; + $SYS_epoll_wait = 238; + $u64_mod_8 = 1; + $SYS_signalfd4 = 313; + $SYS_renameat2 //= 357; + $SYS_fstatfs = 100; + $FS_IOC_GETFLAGS = 0x40086601; + $FS_IOC_SETFLAGS = 0x80086602; + } elsif ($machine =~ m/^s390/) { # untested, no machine on cfarm + $SYS_epoll_create = 249; + $SYS_epoll_ctl = 250; + $SYS_epoll_wait = 251; + $u64_mod_8 = 1; + $SYS_signalfd4 = 322; + $SYS_renameat2 //= 347; + $SYS_fstatfs = 100; + $SYS_sendmsg = 370; + $SYS_recvmsg = 372; + } elsif ($machine eq 'ia64') { # untested, no machine on cfarm + $SYS_epoll_create = 1243; + $SYS_epoll_ctl = 1244; + $SYS_epoll_wait = 1245; + $u64_mod_8 = 1; + $SYS_signalfd4 = 289; + } elsif ($machine eq "alpha") { # untested, no machine on cfarm + # natural alignment, ints are 32-bits + $SYS_epoll_create = 407; + $SYS_epoll_ctl = 408; + $SYS_epoll_wait = 409; + $u64_mod_8 = 1; + $SYS_signalfd4 = 484; + $SFD_CLOEXEC = 010000000; + } elsif ($machine =~ /\A(?:loong|a)arch64\z/ || $machine eq 'riscv64') { + $SYS_epoll_create = 20; # (sys_epoll_create1) + $SYS_epoll_ctl = 21; + $SYS_epoll_wait = 22; # (sys_epoll_pwait) + $u64_mod_8 = 1; + $no_deprecated = 1; + $SYS_signalfd4 = 74; + $SYS_renameat2 //= 276; + $SYS_fstatfs = 44; + $SYS_sendmsg = 211; + $SYS_recvmsg = 212; + $INOTIFY = { + SYS_inotify_init1 => 26, + SYS_inotify_add_watch => 27, + SYS_inotify_rm_watch => 28, + }; + $FS_IOC_GETFLAGS = 0x80086601; + $FS_IOC_SETFLAGS = 0x40086602; + } elsif ($machine =~ m/arm(v\d+)?.*l/) { # ARM OABI (untested on cfarm) + $SYS_epoll_create = 250; + $SYS_epoll_ctl = 251; + $SYS_epoll_wait = 252; + $u64_mod_8 = 1; + $SYS_signalfd4 = 355; + $SYS_renameat2 //= 382; + $SYS_fstatfs = 100; + $SYS_sendmsg = 296; + $SYS_recvmsg = 297; + } elsif ($machine =~ m/^mips64/) { # cfarm only has 32-bit userspace + $SYS_epoll_create = 5207; + $SYS_epoll_ctl = 5208; + $SYS_epoll_wait = 5209; + $u64_mod_8 = 1; + $SYS_signalfd4 = 5283; + $SYS_renameat2 //= 5311; + $SYS_fstatfs = 5135; + $SYS_sendmsg = 5045; + $SYS_recvmsg = 5046; + $FS_IOC_GETFLAGS = 0x40046601; + $FS_IOC_SETFLAGS = 0x80046602; + } elsif ($machine =~ m/^mips/) { # 32-bit, tested on mips64 cfarm host + $SYS_epoll_create = 4248; + $SYS_epoll_ctl = 4249; + $SYS_epoll_wait = 4250; + $u64_mod_8 = 1; + $SYS_signalfd4 = 4324; + $SYS_renameat2 //= 4351; + $SYS_fstatfs = 4100; + $SYS_sendmsg = 4179; + $SYS_recvmsg = 4177; + $FS_IOC_GETFLAGS = 0x40046601; + $FS_IOC_SETFLAGS = 0x80046602; + $SIGNUM{WINCH} = 20; + $INOTIFY = { + SYS_inotify_init1 => 4329, + SYS_inotify_add_watch => 4285, + SYS_inotify_rm_watch => 4286, + }; + } else { + warn <<EOM; +machine=$machine ptrsize=$Config{ptrsize} has no syscall definitions +git clone https://80x24.org/public-inbox.git and +Send the output of ./devel/sysdefs-list to meta\@public-inbox.org +EOM + } + if ($u64_mod_8) { + *epoll_wait = \&epoll_wait_mod8; + *epoll_ctl = \&epoll_ctl_mod8; + } else { + *epoll_wait = \&epoll_wait_mod4; + *epoll_ctl = \&epoll_ctl_mod4; + } +} elsif ($^O =~ /\A(?:freebsd|openbsd|netbsd|dragonfly)\z/) { +# don't use syscall.ph here, name => number mappings are not stable on *BSD +# but the actual numbers are. +# OpenBSD perl redirects syscall perlop to libc functions +# https://cvsweb.openbsd.org/src/gnu/usr.bin/perl/gen_syscall_emulator.pl +# https://www.netbsd.org/docs/internals/en/chap-processes.html#syscall_versioning +# https://wiki.freebsd.org/AddingSyscalls#Backward_compatibily +# (I'm assuming Dragonfly copies FreeBSD, here, too) + $SYS_recvmsg = 27; + $SYS_sendmsg = 28; +} - # Note: do NOT add new syscalls to depend on *.ph, here. - # Better to miss syscalls (so we can fallback to IO::Poll) - # than to use wrong ones, since the names are not stable - # (at least not on FreeBSD), if the actual numbers are. - } +BEGIN { + if ($^O eq 'linux') { + %PACK = ( + TMPL_cmsg_len => TMPL_size_t, + # cmsg_len, cmsg_level, cmsg_type + SIZEOF_cmsghdr => SIZEOF_int * 2 + SIZEOF_size_t, + CMSG_DATA_off => '', + TMPL_msghdr => 'PL' . # msg_name, msg_namelen + '@'.(2 * SIZEOF_ptr).'P'. # msg_iov + 'i'. # msg_iovlen + '@'.(4 * SIZEOF_ptr).'P'. # msg_control + 'L'. # msg_controllen (socklen_t) + 'i', # msg_flags + ); + } elsif ($^O =~ /\A(?:freebsd|openbsd|netbsd|dragonfly)\z/) { + %PACK = ( + TMPL_cmsg_len => 'L', # socklen_t + SIZEOF_cmsghdr => SIZEOF_int * 3, + CMSG_DATA_off => SIZEOF_ptr == 8 ? '@16' : '', + TMPL_msghdr => 'PL' . # msg_name, msg_namelen + '@'.(2 * SIZEOF_ptr).'P'. # msg_iov + TMPL_size_t. # msg_iovlen + '@'.(4 * SIZEOF_ptr).'P'. # msg_control + TMPL_size_t. # msg_controllen + 'i', # msg_flags - if ($u64_mod_8) { - *epoll_wait = \&epoll_wait_mod8; - *epoll_ctl = \&epoll_ctl_mod8; - } else { - *epoll_wait = \&epoll_wait_mod4; - *epoll_ctl = \&epoll_ctl_mod4; - } + ) + } + $PACK{CMSG_ALIGN_size} = SIZEOF_size_t; + $PACK{SIZEOF_cmsghdr} //= 0; + $PACK{TMPL_cmsg_len} //= undef; + $PACK{CMSG_DATA_off} //= undef; + $PACK{TMPL_msghdr} //= undef; } -# use Inline::C for *BSD-only or general POSIX stuff. -# Linux guarantees stable syscall numbering, BSDs only offer a stable libc -# use scripts/syscall-list on Linux to detect new syscall numbers - -############################################################################ -# epoll functions -############################################################################ -sub epoll_defined { $SYS_epoll_create ? 1 : 0; } +# SFD_CLOEXEC is arch-dependent, so IN_CLOEXEC may be, too +$INOTIFY->{IN_CLOEXEC} //= 0x80000 if $INOTIFY; sub epoll_create { syscall($SYS_epoll_create, $no_deprecated ? 0 : 100); @@ -226,10 +333,13 @@ sub epoll_create { # epoll_ctl wrapper # ARGS: (epfd, op, fd, events_mask) sub epoll_ctl_mod4 { - syscall($SYS_epoll_ctl, $_[0]+0, $_[1]+0, $_[2]+0, pack("LLL", $_[3], $_[2], 0)); + syscall($SYS_epoll_ctl, $_[0]+0, $_[1]+0, $_[2]+0, + pack("LLL", $_[3], $_[2], 0)); } + sub epoll_ctl_mod8 { - syscall($SYS_epoll_ctl, $_[0]+0, $_[1]+0, $_[2]+0, pack("LLLL", $_[3], 0, $_[2], 0)); + syscall($SYS_epoll_ctl, $_[0]+0, $_[1]+0, $_[2]+0, + pack("LLLL", $_[3], 0, $_[2], 0)); } # epoll_wait wrapper @@ -242,7 +352,7 @@ sub epoll_wait_mod4 { # resize our static buffer if maxevents bigger than we've ever done if ($maxevents > $epoll_wait_size) { $epoll_wait_size = $maxevents; - vec($epoll_wait_events, $maxevents * 12 * 8 - 1, 1) = 0; + vec($epoll_wait_events, $maxevents * 12 - 1, 8) = 0; } @$events = (); my $ct = syscall($SYS_epoll_wait, $epfd, $epoll_wait_events, @@ -263,7 +373,7 @@ sub epoll_wait_mod8 { # resize our static buffer if maxevents bigger than we've ever done if ($maxevents > $epoll_wait_size) { $epoll_wait_size = $maxevents; - vec($epoll_wait_events, $maxevents * 16 * 8 - 1, 1) = 0; + vec($epoll_wait_events, $maxevents * 16 - 1, 8) = 0; } @$events = (); my $ct = syscall($SYS_epoll_wait, $epfd, $epoll_wait_events, @@ -280,15 +390,15 @@ sub epoll_wait_mod8 { } } -sub signalfd ($$) { - my ($signos, $nonblock) = @_; +sub signalfd ($) { + my ($signos) = @_; if ($SYS_signalfd4) { my $set = POSIX::SigSet->new(@$signos); syscall($SYS_signalfd4, -1, "$$set", # $Config{sig_count} is NSIG, so this is NSIG/8: int($Config{sig_count}/8), # SFD_NONBLOCK == O_NONBLOCK for every architecture - ($nonblock ? O_NONBLOCK : 0) |$SFD_CLOEXEC); + O_NONBLOCK|$SFD_CLOEXEC); } else { $! = ENOSYS; undef; @@ -312,7 +422,7 @@ sub rename_noreplace ($$) { my $ret = syscall($SYS_renameat2, -100, $old, -100, $new, 1); if ($ret == 0) { 1; # like rename() perlop - } elsif ($! == ENOSYS) { + } elsif ($! == ENOSYS || $! == EINVAL) { undef $SYS_renameat2; _rename_noreplace_racy($old, $new); } else { @@ -323,6 +433,102 @@ sub rename_noreplace ($$) { } } +sub nodatacow_fh ($) { + my ($fh) = @_; + my $buf = "\0" x 120; + syscall($SYS_fstatfs // return, fileno($fh), $buf) == 0 or + return warn("fstatfs: $!\n"); + my $f_type = unpack('l!', $buf); # statfs.f_type is a signed word + return if $f_type != 0x9123683E; # BTRFS_SUPER_MAGIC + + $FS_IOC_GETFLAGS // + return warn('FS_IOC_GETFLAGS undefined for platform'); + ioctl($fh, $FS_IOC_GETFLAGS, $buf) // + return warn("FS_IOC_GETFLAGS: $!\n"); + my $attr = unpack('l!', $buf); + return if ($attr & 0x00800000); # FS_NOCOW_FL; + ioctl($fh, $FS_IOC_SETFLAGS, pack('l', $attr | 0x00800000)) // + warn("FS_IOC_SETFLAGS: $!\n"); +} + +sub nodatacow_dir { + if (open my $fh, '<', $_[0]) { nodatacow_fh($fh) } +} + +use constant \%PACK; +sub CMSG_ALIGN ($) { ($_[0] + CMSG_ALIGN_size - 1) & ~(CMSG_ALIGN_size - 1) } +use constant CMSG_ALIGN_SIZEOF_cmsghdr => CMSG_ALIGN(SIZEOF_cmsghdr); +sub CMSG_SPACE ($) { CMSG_ALIGN($_[0]) + CMSG_ALIGN_SIZEOF_cmsghdr } +sub CMSG_LEN ($) { CMSG_ALIGN_SIZEOF_cmsghdr + $_[0] } +use constant msg_controllen_max => + CMSG_SPACE(10 * SIZEOF_int) + SIZEOF_cmsghdr; # space for 10 FDs + +if (defined($SYS_sendmsg) && defined($SYS_recvmsg)) { +no warnings 'once'; +require PublicInbox::CmdIPC4; + +*send_cmd4 = sub ($$$$;$) { + my ($sock, $fds, undef, $flags, $tries) = @_; + my $iov = pack('P'.TMPL_size_t, + $_[2] // NUL, length($_[2] // NUL) || 1); + my $fd_space = scalar(@$fds) * SIZEOF_int; + my $msg_controllen = CMSG_SPACE($fd_space); + my $cmsghdr = pack(TMPL_cmsg_len . + 'LL' . # cmsg_level, cmsg_type, + CMSG_DATA_off.('i' x scalar(@$fds)). # CMSG_DATA + '@'.($msg_controllen - 1).'x1', # pad to space, not len + CMSG_LEN($fd_space), # cmsg_len + SOL_SOCKET, SCM_RIGHTS, # cmsg_{level,type} + @$fds); # CMSG_DATA + my $mh = pack(TMPL_msghdr, + undef, 0, # msg_name, msg_namelen (unused) + $iov, 1, # msg_iov, msg_iovlen + $cmsghdr, # msg_control + $msg_controllen, + 0); # msg_flags + my $s; + $tries //= 50; + do { + $s = syscall($SYS_sendmsg, fileno($sock), $mh, $flags); + } while ($s < 0 && PublicInbox::CmdIPC4::sendmsg_retry($tries)); + $s >= 0 ? $s : undef; +}; + +*recv_cmd4 = sub ($$$) { + my ($sock, undef, $len) = @_; + vec($_[1] //= '', $len - 1, 8) = 0; + my $cmsghdr = "\0" x msg_controllen_max; # 10 * sizeof(int) + my $iov = pack('P'.TMPL_size_t, $_[1], $len); + my $mh = pack(TMPL_msghdr, + undef, 0, # msg_name, msg_namelen (unused) + $iov, 1, # msg_iov, msg_iovlen + $cmsghdr, # msg_control + msg_controllen_max, + 0); # msg_flags + my $r; + do { + $r = syscall($SYS_recvmsg, fileno($sock), $mh, 0); + } while ($r < 0 && $!{EINTR}); + if ($r < 0) { + $_[1] = ''; + return (undef); + } + substr($_[1], $r, length($_[1]), ''); + my @ret; + if ($r > 0) { + my ($len, $lvl, $type, @fds) = unpack(TMPL_cmsg_len. + 'LL'. # cmsg_level, cmsg_type + CMSG_DATA_off.'i*', # @fds + $cmsghdr); + if ($lvl == SOL_SOCKET && $type == SCM_RIGHTS) { + $len -= CMSG_ALIGN_SIZEOF_cmsghdr; + @ret = @fds[0..(($len / SIZEOF_int) - 1)]; + } + } + @ret; +}; +} + 1; =head1 WARRANTY |