qspawn: improve variable naming and commenting

Naming $start_cb consistently helps avoid confusing new readers,
and some comments will help with understanding flow

diff --git a/lib/PublicInbox/GitHTTPBackend.pm b/lib/PublicInbox/GitHTTPBackend.pm
index c9a7cff88cc419bc71241006511d42ac7b4ec4d5..ec8e651699f4d3e521489483e7d337055fd0b75e 100644 (file)
--- a/lib/PublicInbox/GitHTTPBackend.pm
+++ b/lib/PublicInbox/GitHTTPBackend.pm
@@ -204,7 +204,7 @@ sub serve_smart {
        $env{PATH_TRANSLATED} = "$git->{git_dir}/$path";
        my $rdr = input_prepare($env) or return r(500);
        my $qsp = PublicInbox::Qspawn->new([qw(git http-backend)], \%env, $rdr);
-       $qsp->psgi_return($env, $limiter, sub {
+       $qsp->psgi_return($env, $limiter, sub { # parse_hdr
                my ($r, $bref) = @_;
                my $res = parse_cgi_headers($r, $bref) or return; # incomplete
                $res->[0] == 403 ? serve_dumb($env, $git, $path) : $res;

diff --git a/lib/PublicInbox/Qspawn.pm b/lib/PublicInbox/Qspawn.pm
index 10fe534112b5d29e5c75ada28fa9b337f9d1e176..5a300644fe3df0b3ad49d5d22b904eef77e89385 100644 (file)
--- a/lib/PublicInbox/Qspawn.pm
+++ b/lib/PublicInbox/Qspawn.pm
@@ -44,7 +44,7 @@ sub new ($$$;) {
 }
 
 sub _do_spawn {
-       my ($self, $cb, $limiter) = @_;
+       my ($self, $start_cb, $limiter) = @_;
        my $err;
        my ($cmd, $env, $opts) = @{$self->{args}};
        my %opts = %{$opts || {}};
@@ -66,7 +66,7 @@ sub _do_spawn {
        } else {
                $self->{err} = $!;
        }
-       $cb->($self->{rpipe});
+       $start_cb->($self->{rpipe});
 }
 
 sub child_err ($) {
@@ -135,11 +135,11 @@ sub finish ($;$) {
 }
 
 sub start {
-       my ($self, $limiter, $cb) = @_;
+       my ($self, $limiter, $start_cb) = @_;
        if ($limiter->{running} < $limiter->{max}) {
-               _do_spawn($self, $cb, $limiter);
+               _do_spawn($self, $start_cb, $limiter);
        } else {
-               push @{$limiter->{run_queue}}, [ $self, $cb ];
+               push @{$limiter->{run_queue}}, [ $self, $start_cb ];
        }
 }
 
@@ -175,11 +175,12 @@ reread:
                }
        };
        $limiter ||= $def_limiter ||= PublicInbox::Qspawn::Limiter->new(32);
-       $self->start($limiter, sub { # may run later, much later...
+       $self->start($limiter, sub { # start_cb, may run later, much later...
                ($rpipe) = @_; # popen_rd result
                if ($async) {
                # PublicInbox::HTTPD::Async->new($rpipe, $cb, $end)
                        $async = $async->($rpipe, $cb, $end);
+                       # $cb will call ->async_pass or ->close
                } else { # generic PSGI
                        $cb->() while $qx;
                }
@@ -254,7 +255,7 @@ sub psgi_return {
                $ret;
        };
 
-       my $wcb = delete $env->{'qspawn.wcb'};
+       my $wcb = delete $env->{'qspawn.wcb'}; # or PSGI server supplies it
        my $async = $env->{'pi-httpd.async'};
 
        my $cb = sub {
@@ -287,6 +288,7 @@ sub psgi_return {
                if ($async) {
                        # PublicInbox::HTTPD::Async->new($rpipe, $cb, $end)
                        $async = $async->($rpipe, $cb, $end);
+                       # $cb will call ->async_pass or ->close
                } else { # generic PSGI
                        $cb->() while $rd_hdr;
                }