solver: switch patch application to use a callback

A bit messy at the moment, but we need to break this up
into smaller steps for fairness with other clients, as
applying dozens of patches can take several hundred
milliseconds.

diff --git a/lib/PublicInbox/SolverGit.pm b/lib/PublicInbox/SolverGit.pm
index 71494e07b5426f9e656c5adeccdcb37daf9dbf86..70d8a93426d161a0aba73c0f0bb64b561038562c 100644 (file)
--- a/lib/PublicInbox/SolverGit.pm
+++ b/lib/PublicInbox/SolverGit.pm
@@ -290,16 +290,35 @@ sub di_url ($) {
        defined($url) ? "$url$mid/" : "<$mid>";
 }
 
-sub apply_patches ($$$$$) {
-       my ($self, $out, $wt, $found, $patches) = @_;
+sub apply_patches_cb ($$$$$) {
+       my ($self, $out, $found, $patches, $oid_b) = @_;
+       my $wt = do_git_init_wt($self);
        my $wt_dir = $wt->dirname;
        my $wt_git = PublicInbox::Git->new("$wt_dir/.git");
        $wt_git->{-wt} = $wt;
 
        my $cur = 0;
        my $tot = scalar @$patches;
+       my ($apply_pid, $rd, $di);
+
+       # returns an empty string if in progress, undef if not found,
+       # or the final [ ::Git, oid_full, type, size, $di ] arrayref
+       # if found
+       sub {
+               if ($rd) {
+                       $found->{$di->{oid_b}} =
+                                       do_apply_end($out, $wt_git, $rd, $di);
+                       $rd = undef;
+                       # continue to shift @$patches
+               } elsif ($apply_pid) {
+                       $rd = do_apply_continue($wt_dir, $apply_pid);
+                       $apply_pid = undef;
+                       return ''; # $rd => do_apply_ned
+               }
+
+               # may return undef here
+               $di = shift @$patches or return $found->{$oid_b};
 
-       foreach my $di (@$patches) {
                my $i = ++$cur;
                my $oid_a = $di->{oid_a};
                my $existing = $found->{$oid_a};
@@ -321,29 +340,10 @@ sub apply_patches ($$$$$) {
                           join('', @{$di->{hdr_lines}}), "\n"
                        or die "print \$out failed: $!";
 
-               # apply the patch!
-               my $apply_pid = do_apply_begin($out, $wt_dir, $di);
-               my $rd = do_apply_continue($wt_dir, $apply_pid);
-               $found->{$di->{oid_b}} = do_apply_end($out, $wt_git, $rd, $di);
-       }
-}
-
-sub dump_found ($$) {
-       my ($out, $found) = @_;
-       foreach my $oid (sort keys %$found) {
-               my ($git, $oid, undef, undef, $di) = @{$found->{$oid}};
-               my $loc = $di ? di_url($di) : $git->src_blob_url($oid);
-               print $out "$oid from $loc\n";
-       }
-}
-
-sub dump_patches ($$) {
-       my ($out, $patches) = @_;
-       my $tot = scalar(@$patches);
-       my $i = 0;
-       foreach my $di (@$patches) {
-               ++$i;
-               print $out "[$i/$tot] ", di_url($di), "\n";
+               # begin the patch application patch!
+               $apply_pid = do_apply_begin($out, $wt_dir, $di);
+               # next call to this callback will call do_apply_continue
+               '';
        }
 }
 
@@ -415,24 +415,16 @@ sub solve ($$$$) {
 
        unless (scalar(@$patches)) {
                print $out "no patch(es) for $oid_b\n";
-               dump_found($out, $found);
                return;
        }
 
        # reconstruct the oid_b blob using patches we found:
-       eval {
-               my $wt = do_git_init_wt($self);
-               apply_patches($self, $out, $wt, $found, $patches);
-       };
-       if ($@) {
-               print $out "E: $@\nfound: ";
-               dump_found($out, $found);
-               print $out "patches: ";
-               dump_patches($out, $patches);
-               return;
+       my $cb = apply_patches_cb($self, $out, $found, $patches, $oid_b);
+       my $ret;
+       while (1) {
+               $ret = $cb->();
+               return $ret if (ref($ret) || !defined($ret));
        }
-
-       $found->{$oid_b};
 }
 
 1;