# Copyright (C) all contributors
# License: AGPL-3.0+
# Just-ahead-of-time builder for the lib/PublicInbox/xap_helper.h shim.
# I never want users to be without source code for repairs, so this
# aims to replicate the feel of a scripting language using C++.
# The resulting executable is not linked to Perl in any way.
package PublicInbox::XapHelperCxx;
use v5.12;
use PublicInbox::Spawn qw(run_die run_qx run_wait which);
use PublicInbox::IO qw(try_cat write_file);
use PublicInbox::Search;
use Fcntl qw(SEEK_SET);
use Config;
use autodie;
my $cxx = which($ENV{CXX} // 'c++') // which('clang') // die 'no C++ compiler';
my $dir = substr("$cxx-$Config{archname}", 1); # drop leading '/'
$dir =~ tr!/!-!;
my $idir;
if ((defined($ENV{XDG_CACHE_HOME}) && -d $ENV{XDG_CACHE_HOME}) ||
(defined($ENV{HOME}) && -d $ENV{HOME})) {
$idir = ($ENV{XDG_CACHE_HOME} //
(($ENV{HOME} // die('HOME unset')).'/.cache')
).'/public-inbox/jaot';
}
$idir //= $ENV{PERL_INLINE_DIRECTORY} //
die 'HOME and PERL_INLINE_DIRECTORY unset';
substr($dir, 0, 0) = "$idir/";
my $bin = "$dir/xap_helper";
my ($srcpfx) = (__FILE__ =~ m!\A(.+/)[^/]+\z!);
my @srcs = map { $srcpfx.$_ } qw(xh_mset.h xh_cidx.h xap_helper.h);
my @pm_dep = map { $srcpfx.$_ } qw(Search.pm CodeSearch.pm);
my $ldflags = '-Wl,-O1';
$ldflags .= ' -Wl,--compress-debug-sections=zlib' if $^O ne 'openbsd';
my $xflags = ($ENV{CXXFLAGS} // '-Wall -ggdb3 -pipe') . ' ' .
' -DTHREADID=' . PublicInbox::Search::THREADID .
' -DXH_SPEC="'.join('',
map { s/=.*/:/; $_ } @PublicInbox::Search::XH_SPEC) . '" ' .
($ENV{LDFLAGS} // $ldflags);
substr($xflags, 0, 0, '-O2 ') if !defined($ENV{CXXFLAGS}) && !-w __FILE__;
my $xap_modversion;
sub xap_cfg (@) {
my $cmd = [ $ENV{PKG_CONFIG} // 'pkg-config', @_, 'xapian-core' ];
chomp(my $ret = run_qx($cmd, undef, { 2 => \(my $err) }));
return $ret if !$?;
die <new("$dir/$prog.lock")->lock_for_scope;
write_file '>', "$dir/$prog.cpp", qq{#include "xap_helper.h"\n},
PublicInbox::Search::generate_cxx(),
PublicInbox::CodeSearch::generate_cxx();
# xap_modversion may be set by needs_rebuild
$xap_modversion //= xap_cfg('--modversion');
my $fl = xap_cfg(qw(--libs --cflags));
# Using rpath seems acceptable/encouraged in the NetBSD packaging world
# since /usr/pkg/lib isn't searched by the dynamic loader by default.
# Not sure if other OSes need this, but rpath seems fine for JAOT
# binaries (like this one) even if other distros discourage it for
# distributed packages.
$^O eq 'netbsd' and $fl =~ s/(\A|[ \t])\-L([^ \t]+)([ \t]|\z)/
"$1-L$2 -Wl,-rpath=$2$3"/egsx;
my @xflags = split(' ', "$fl $xflags"); # ' ' awk-mode eats leading WS
my @cflags = ('-I', $srcpfx, grep(!/\A-(?:Wl|l|L)/, @xflags));
run_die([$cxx, '-o', "$dir/$prog.o", '-c', "$dir/$prog.cpp", @cflags]);
# xapian on Alpine Linux (tested 3.19.0) is linked against libstdc++,
# and clang needs to be told to use it (rather than libc++):
my @try = rindex($cxx, 'clang') >= 0 ? qw(-lstdc++) : ();
my @cmd = ($cxx, '-o', "$dir/$prog.tmp", "$dir/$prog.o", @xflags);
while (run_wait(\@cmd) and @try) {
warn("# attempting to link again with $try[0]...\n");
push(@cmd, shift(@try));
}
die "# @cmd failed: \$?=$?" if $?;
unlink "$dir/$prog.cpp", "$dir/$prog.o";
write_file '>', "$dir/XFLAGS.tmp", $xflags, "\n";
write_file '>', "$dir/xap_modversion.tmp", $xap_modversion, "\n";
undef $xap_modversion; # do we ever build() twice?
# not quite atomic, but close enough :P
rename("$dir/$_.tmp", "$dir/$_") for ($prog, qw(XFLAGS xap_modversion));
}
sub check_build () {
use Time::HiRes qw(stat);
my $ctime = 0;
my @bin = stat($bin) or return build();
for (@srcs, @pm_dep) {
my @st = stat($_) or die "stat $_: $!";
if ($st[10] > $ctime) {
$ctime = $st[10];
return build() if $ctime > $bin[10];
}
}
needs_rebuild() ? build() : 0;
}
# returns spawn arg
sub cmd {
die 'PI_NO_CXX set' if $ENV{PI_NO_CXX};
check_build();
my @cmd;
if (my $v = $ENV{VALGRIND}) {
$v = 'valgrind -v' if $v eq '1';
@cmd = split(/\s+/, $v);
}
push @cmd, $bin;
\@cmd;
}
1;