git: show more context info on failures

[public-inbox.git] / lib / PublicInbox / Git.pm

diff --git a/lib/PublicInbox/Git.pm b/lib/PublicInbox/Git.pm
index ffc464eb32d22c11c91bbd4caabdcb883752e203..181026c7bc1b726ff562e1b488f3256a0bf98c87 100644 (file)
--- a/lib/PublicInbox/Git.pm
+++ b/lib/PublicInbox/Git.pm
@@ -17,6 +17,7 @@ use File::Glob qw(bsd_glob GLOB_NOSORT);
 use Time::HiRes qw(stat);
 use PublicInbox::Spawn qw(popen_rd);
 use PublicInbox::Tmpfile;
+use Carp qw(croak);
 our @EXPORT_OK = qw(git_unquote git_quote);
 our $PIPE_BUFSIZ = 65536; # Linux default
 our $in_cleanup;
@@ -319,7 +320,7 @@ sub cat_async_abort ($) {
 sub fail {
        my ($self, $msg) = @_;
        $self->{inflight} ? cat_async_abort($self) : cleanup($self);
-       die $msg;
+       croak("git $self->{git_dir}: $msg");
 }
 
 sub popen {
@@ -410,6 +411,22 @@ sub cat_async ($$$;$) {
        push(@$inflight, $oid, $cb, $arg);
 }
 
+# this is safe to call inside $cb, but not guaranteed to enqueue
+# returns true if successful, undef if not.
+sub async_prefetch {
+       my ($self, $oid, $cb, $arg) = @_;
+       if (defined($self->{async_cat}) && (my $inflight = $self->{inflight})) {
+               # we could use MAX_INFLIGHT here w/o the halving,
+               # but lets not allow one client to monopolize a git process
+               if (scalar(@$inflight) < int(MAX_INFLIGHT/2)) {
+                       print { $self->{out} } $oid, "\n" or
+                                               fail($self, "write error: $!");
+                       return push(@$inflight, $oid, $cb, $arg);
+               }
+       }
+       undef;
+}
+
 sub extract_cmt_time {
        my ($bref, undef, undef, undef, $modified) = @_;