- $env{PATH_TRANSLATED} = "$git_dir/$path";
- my %rdr = ( 0 => fileno($in), 1 => fileno($wpipe) );
- my $pid = spawn([qw(git http-backend)], \%env, \%rdr);
- unless (defined $pid) {
- err($env, "error spawning: $! - going static");
- return;
- }
- $wpipe = $in = undef;
- $buf = '';
- my ($vin, $fh, $res);
- $nr_running++;
-
- # Danga::Socket users, we queue up the read_enable callback to
- # fire after pending writes are complete:
- my $pi_http = $env->{'psgix.io'};
- my $read_enable = sub { $rpipe->watch_read(1) };
- my $read_disable = sub {
- $rpipe->watch_read(0);
- $pi_http->write($read_enable);
- };
-
- my $end = sub {
- if ($fh) {
- $fh->close;
- $fh = undef;
- }
- if ($rpipe) {
- # _may_ be Danga::Socket::close via
- # PublicInbox::HTTPD::Async::close:
- $rpipe->close;
- $rpipe = undef;
- $nr_running--;
- }
- if (defined $pid) {
- my $e = $pid == waitpid($pid, 0) ?
- $? : "PID:$pid still running?";
- err($env, "git http-backend ($git_dir): $e") if $e;
- }
- return unless $res;
- my $dumb = serve_dumb($cgi, $git, $path);
- ref($dumb) eq 'ARRAY' ? $res->($dumb) : $dumb->($res);
- };
- my $fail = sub {
- if ($!{EAGAIN} || $!{EINTR}) {
- select($vin, undef, undef, undef) if defined $vin;
- # $vin is undef on async, so this is a noop on EAGAIN
- return;
- }
- my $e = $!;
- $end->();
- err($env, "git http-backend ($git_dir): $e\n");
- };
- my $cb = sub { # read git-http-backend output and stream to client
- my $r = $rpipe ? $rpipe->sysread($buf, 8192, length($buf)) : 0;
- return $fail->() unless defined $r;
- return $end->() if $r == 0; # EOF
- if ($fh) { # stream body from git-http-backend to HTTP client
- $fh->write($buf);
- $buf = '';
- $read_disable->() if $read_disable;
- } elsif ($buf =~ s/\A(.*?)\r\n\r\n//s) { # parse headers
- my $h = $1;
- my $code = 200;
- my @h;
- foreach my $l (split(/\r\n/, $h)) {
- my ($k, $v) = split(/:\s*/, $l, 2);
- if ($k =~ /\AStatus\z/i) {
- ($code) = ($v =~ /\b(\d+)\b/);
- } else {
- push @h, $k, $v;
- }
- }
- if ($code == 403) {
- # smart cloning disabled, serve dumbly
- # in $end since we never undef $res in here
- } else { # write response header:
- $fh = $res->([ $code, \@h ]);
- $res = undef;
- $fh->write($buf);
- }
- $buf = '';
- } # else { keep reading ... }
- };
- if (my $async = $env->{'pi-httpd.async'}) {
- # $async is PublicInbox::HTTPD::Async->new($rpipe, $cb)
- $rpipe = $async->($rpipe, $cb);
- sub { ($res) = @_ } # let Danga::Socket handle the rest.
- } else { # synchronous loop for other PSGI servers
- $read_enable = $read_disable = undef;
- $vin = '';
- vec($vin, fileno($rpipe), 1) = 1;
- sub {
- ($res) = @_;
- while ($rpipe) { $cb->() }
- }
- }