# processes such as git-apply(1).
package PublicInbox::Qspawn;
-use strict;
-use v5.10.1;
+use v5.12;
use PublicInbox::Spawn qw(popen_rd);
use PublicInbox::GzipFilter;
+use PublicInbox::DS qw(awaitpid);
+use Scalar::Util qw(blessed);
# n.b.: we get EAGAIN with public-inbox-httpd, and EINTR on other PSGI servers
use Errno qw(EAGAIN EINTR);
# $cmd_env is the environ for the child process (not PSGI env)
# $opt can include redirects and perhaps other process spawning options
# {qsp_err} is an optional error buffer callers may access themselves
-sub new ($$$;) {
+sub new {
my ($class, $cmd, $cmd_env, $opt) = @_;
bless { args => [ $cmd, $cmd_env, $opt ] }, $class;
}
}
}
$self->{cmd} = $o{quiet} ? undef : $cmd;
+ $o{cb_arg} = [ \&waitpid_err, $self ];
eval {
# popen_rd may die on EMFILE, ENFILE
- $self->{rpipe} = popen_rd($cmd, $cmd_env, \%o);
-
- die "E: $!" unless defined($self->{rpipe});
-
+ $self->{rpipe} = popen_rd($cmd, $cmd_env, \%o) // die "E: $!";
$limiter->{running}++;
$start_cb->($self); # EPOLL_CTL_ADD may ENOSPC/ENOMEM
};
finish($self, $@) if $@;
}
-sub child_err ($) {
- my ($child_error) = @_; # typically $?
- my $exitstatus = ($child_error >> 8) or return;
- my $sig = $child_error & 127;
- my $msg = "exit status=$exitstatus";
- $msg .= " signal=$sig" if $sig;
- $msg;
-}
-
-sub finalize ($$) {
- my ($self, $err) = @_;
-
- my ($env, $qx_cb, $qx_arg, $qx_buf) =
- delete @$self{qw(psgi_env qx_cb qx_arg qx_buf)};
+sub finalize ($) {
+ my ($self) = @_;
- # done, spawn whatever's in the queue
- my $limiter = $self->{limiter};
+ # process is done, spawn whatever's in the queue
+ my $limiter = delete $self->{limiter} or return;
my $running = --$limiter->{running};
if ($running < $limiter->{max}) {
_do_spawn(@$next, $limiter);
}
}
-
- if ($err) {
+ if (my $err = $self->{_err}) { # set by finish or waitpid_err
utf8::decode($err);
if (my $dst = $self->{qsp_err}) {
$$dst .= $$dst ? " $err" : "; $err";
}
warn "@{$self->{cmd}}: $err" if $self->{cmd};
}
+
+ my ($env, $qx_cb, $qx_arg, $qx_buf) =
+ delete @$self{qw(psgi_env qx_cb qx_arg qx_buf)};
if ($qx_cb) {
eval { $qx_cb->($qx_buf, $qx_arg) };
return unless $@;
warn "E: $@"; # hope qspawn.wcb can handle it
}
+ return if $self->{passed}; # another command chained it
if (my $wcb = delete $env->{'qspawn.wcb'}) {
# have we started writing, yet?
+ my $code = delete $env->{'qspawn.fallback'} // 500;
require PublicInbox::WwwStatic;
- $wcb->(PublicInbox::WwwStatic::r(500));
+ $wcb->(PublicInbox::WwwStatic::r($code));
}
}
-# callback for dwaitpid or ProcessPipe
-sub waitpid_err { finalize($_[0], child_err($?)) }
+sub DESTROY { finalize($_[0]) } # ->finalize is idempotent
+
+sub waitpid_err { # callback for awaitpid
+ my (undef, $self) = @_; # $_[0]: pid
+ $self->{_err} = ''; # for defined check in ->finish
+ if ($?) {
+ my $status = $? >> 8;
+ my $sig = $? & 127;
+ $self->{_err} .= "exit status=$status";
+ $self->{_err} .= " signal=$sig" if $sig;
+ }
+ finalize($self) if !$self->{rpipe};
+}
sub finish ($;$) {
my ($self, $err) = @_;
- my $tied_pp = delete($self->{rpipe}) or return finalize($self, $err);
- my PublicInbox::ProcessPipe $pp = tied *$tied_pp;
- @$pp{qw(cb arg)} = (\&waitpid_err, $self); # for ->DESTROY
+ $self->{_err} //= $err; # only for $@
+
+ # we can safely finalize if pipe was closed before, or if
+ # {_err} is defined by waitpid_err. Deleting {rpipe} will
+ # trigger PublicInbox::ProcessPipe::DESTROY -> waitpid_err,
+ # but it may not fire right away if inside the event loop.
+ my $closed_before = !delete($self->{rpipe});
+ finalize($self) if $closed_before || defined($self->{_err});
}
sub start ($$$) {
}
}
-sub psgi_qx_init_cb {
+sub psgi_qx_init_cb { # this may be PublicInbox::HTTPD::Async {cb}
my ($self) = @_;
my $async = delete $self->{async}; # PublicInbox::HTTPD::Async
my ($r, $buf);
my ($self, $err) = @_; # $err: $!
warn "psgi_{return,qx} $err" if defined($err);
finish($self);
- my ($fh, $qx_fh) = delete(@$self{qw(fh qx_fh)});
+ my ($fh, $qx_fh) = delete(@$self{qw(qfh qx_fh)});
$fh->close if $fh; # async-only (psgi_return)
}
my $total_rd = 0;
my $hdr_buf = $self->{hdr_buf};
my ($ph_cb, $ph_arg) = @{$self->{parse_hdr}};
- do {
+ until (defined($ret)) {
my $r = sysread($self->{rpipe}, $$hdr_buf, 4096,
length($$hdr_buf));
if (defined($r)) {
if ($@) {
warn "parse_hdr: $@";
$ret = [ 500, [], [ "Internal error\n" ] ];
+ } elsif (!defined($ret) && !$r) {
+ my $cmd = $self->{cmd} // [ '(?)' ];
+ warn <<EOM;
+EOF parsing headers from @$cmd ($self->{psgi_env}->{REQUEST_URI})
+EOM
+ $ret = [ 500, [], [ "Internal error\n" ] ];
}
} else {
# caller should notify us when it's ready:
warn "error reading header: $!";
$ret = [ 500, [], [ "Internal error\n" ] ];
}
- } until (defined $ret);
+ }
delete $self->{parse_hdr}; # done parsing headers
$ret;
}
-sub psgi_return_init_cb {
+sub psgi_return_init_cb { # this may be PublicInbox::HTTPD::Async {cb}
my ($self) = @_;
my $r = rd_hdr($self) or return;
my $env = $self->{psgi_env};
- my $filter = delete($env->{'qspawn.filter'}) // (ref($r) eq 'ARRAY' ?
+ my $filter;
+
+ # this is for RepoAtom since that can fire after parse_cgi_headers
+ if (ref($r) eq 'ARRAY' && blessed($r->[2]) && $r->[2]->can('attach')) {
+ $filter = pop @$r;
+ }
+ $filter //= delete($env->{'qspawn.filter'}) // (ref($r) eq 'ARRAY' ?
PublicInbox::GzipFilter::qsp_maybe($r->[1], $env) : undef);
my $wcb = delete $env->{'qspawn.wcb'};
if (ref($r) ne 'ARRAY' || scalar(@$r) == 3) { # error
if ($async) { # calls rpipe->close && ->event_step
$async->close; # PublicInbox::HTTPD::Async::close
- } else {
- $self->{rpipe}->close;
+ } else { # generic PSGI, use PublicInbox::ProcessPipe::CLOSE
+ delete($self->{rpipe})->close;
event_step($self);
}
- $wcb->($r) if ref($r) eq 'ARRAY';
+ if (ref($r) eq 'ARRAY') { # error
+ $wcb->($r)
+ } elsif (ref($r) eq 'CODE') { # chain another command
+ $r->($wcb);
+ $self->{passed} = 1;
+ }
+ # else do nothing
} elsif ($async) {
# done reading headers, handoff to read body
my $fh = $wcb->($r); # scalar @$r == 2
$fh = $filter->attach($fh) if $filter;
- $self->{fh} = $fh;
+ $self->{qfh} = $fh;
$async->async_pass($env->{'psgix.io'}, $fh,
delete($self->{hdr_buf}));
} else { # for synchronous PSGI servers
}
package PublicInbox::Qspawn::Limiter;
-use strict;
-use warnings;
+use v5.12;
sub new {
my ($class, $max) = @_;