Mirroring: Run mirror hook script, if one is provided

diff --git a/infra/dgit-repos-server b/infra/dgit-repos-server
index 1be6e78d26613f27ce3a172cd2bbb0962d5780da..92f197b0b001b31bc5dd11907ab7ab1c1359a00f 100755 (executable)
--- a/infra/dgit-repos-server
+++ b/infra/dgit-repos-server
@@ -9,8 +9,10 @@
 #   --suites=SUITES-FILE       default DISTRO-DIR/suites
 #   --suites-master=SUITES-FILE default DISTRO-DIR/suites-master
 #   --policy-hook=POLICY-HOOK  default DISTRO-DIR/policy-hook
+#   --mirror-hook=MIRROR-HOOK  default DISTRO-DIR/mirror-hook
 #   --dgit-live=DGIT-LIVE-DIR  default DISTRO-DIR/dgit-live
-# (DISTRO-DIR is not used other than as default and to pass to policy hook)
+# (DISTRO-DIR is not used other than as default and to pass to policy
+# and mirror hooks)
 # internal usage:
 #  .../dgit-repos-server --pre-receive-hook PACKAGE
 #
@@ -119,7 +121,7 @@ $SIG{__WARN__} = sub { die $_[0]; };
 #    a stampfile whose presence indicates that there may be
 #    cleanup to do
 #
-# Policy hook script is invoked like this:
+# Policy hook scripts are invoked like this:
 #   POLICY-HOOK-SCRIPT DISTRO DGIT-REPOS-DIR DGIT-LIVE-DIR DISTRO-DIR ACTION...
 # ie.
 #   POLICY-HOOK-SCRIPT ... check-list [...]
@@ -131,7 +133,8 @@ $SIG{__WARN__} = sub { die $_[0]; };
 #
 # DELIBERATELIES is like this: --deliberately-foo,--deliberately-bar,...
 #
-# Exit status is a bitmask.  Bit weight constants are defined in Dgit.pm.
+# Exit status of policy hook is a bitmask.
+# Bit weight constants are defined in Dgit.pm.
 #    NOFFCHECK   (2)
 #         suppress dgit-repos-server's fast-forward check ("push" only)
 #    FRESHREPO   (4)
@@ -168,7 +171,18 @@ $SIG{__WARN__} = sub { die $_[0]; };
 # If policy hook wants to run dgit (or something else in the dgit
 # package), it should use DGIT-LIVE-DIR/dgit (etc.), or if that is
 # ENOENT, use the installed version.
-
+#
+# Mirror hook scripts are invoked like this:
+#   MIRROR-HOOK-SCRIPT DISTRO-DIR ACTION...
+# and currently there is only one action invoked by dgit-repos-server:
+#   MIRROR-HOOK-SCRIPT DISTRO-DIR updated-hook PACKAGE [...]
+#
+# Exit status of the mirror hook is advisory only.  The mirror hook
+# runs too late to do anything useful about a problem, so the only
+# effect of a mirror hook exiting nonzero is a warning message to
+# stderr (which the pushing user should end up seeing).
+#
+# If the mirror hook does not exist, it is silently skipped.
 
 use POSIX;
 use Fcntl qw(:flock);
@@ -186,6 +200,7 @@ our $distro;
 our $suitesfile;
 our $suitesformasterfile;
 our $policyhook;
+our $mirrorhook;
 our $dgitlive;
 our $distrodir;
 our $destrepo;
@@ -278,7 +293,7 @@ sub policyhook {
     # => ($exitstatuspolicybitmap);
     die if $policyallowbits & ~0x3e;
     my @cmd = ($policyhook,$distro,$dgitrepos,$dgitlive,$distrodir,@polargs);
-    debugcmd '+',@cmd;
+    debugcmd '+M',@cmd;
     my $r = system @cmd;
     die "system: $!" if $r < 0;
     die "dgit-repos-server: policy hook failed (or rejected) ($?)\n"
@@ -390,6 +405,23 @@ sub dealwithfreshrepo () {
     $destrepo = $freshrepo;
 }
 
+sub mirrorhook {
+    my @cmd = ($mirrorhook,$distrodir,@_);
+    debugcmd '+',@cmd;
+    return unless stat_exists $mirrorhook;
+    my $r = system @cmd;
+    if ($r) {
+       printf STDERR <<END,
+dgit-repos-server: warning: mirror hook failed: %s
+dgit-repos-server: push complete but may not fully visible.
+END
+            ($r < 0 ? "exec: $!" :
+            $r == (124 << 8) ? "exited status 124 (timeout?)" :
+            !($r & ~0xff00) ? "exited ".($? >> 8) :
+            "wait status $?");
+    }
+}
+
 sub maybeinstallprospective () {
     return if $destrepo eq realdestrepo;
 
@@ -447,6 +479,7 @@ sub main__git_receive_pack () {
     runcmd qw(git receive-pack), $workrepo;
     dealwithfreshrepo();
     maybeinstallprospective();
+    mirrorhook('updated-hook', $package);
 }
 
 #----- stunt post-receive hook -----
@@ -928,11 +961,12 @@ our %indistrodir = (
     'suites' => \$suitesfile,
     'suites-master' => \$suitesformasterfile,
     'policy-hook' => \$policyhook,
+    'mirror-hook' => \$mirrorhook,
     'dgit-live' => \$dgitlive,
     );
 
 our @hookenvs = qw(distro suitesfile suitesformasterfile policyhook
-                   dgitlive keyrings dgitrepos distrodir);
+                   mirrorhook dgitlive keyrings dgitrepos distrodir);
 
 # workrepo and destrepo handled ad-hoc