From ea553b5beecd938ab24e1493ad76bbc24507b598 Mon Sep 17 00:00:00 2001
From: ellie timoney <ellie@fastmail.com>
Date: Wed, 21 Jun 2023 11:59:03 +1000
Subject: [PATCH] Instance: run fakesaslauthd as a wait=y DAEMON

not strictly related to this PR, but I've been wanting to do this
for ages, and now I can, and it shows that the previous commit works
---
 cassandane/Cassandane/Cyrus/Info.pm |  5 +++++
 cassandane/Cassandane/Instance.pm   | 35 ++++++++++++++++++++---------
 cassandane/utils/fakesaslauthd      | 19 +++++++++++++++-
 3 files changed, 47 insertions(+), 12 deletions(-)

diff --git a/cassandane/Cassandane/Cyrus/Info.pm b/cassandane/Cassandane/Cyrus/Info.pm
index 5e9e512ae1..4047246ba2 100644
--- a/cassandane/Cassandane/Cyrus/Info.pm
+++ b/cassandane/Cassandane/Cyrus/Info.pm
@@ -88,6 +88,11 @@ sub run_cyr_info
     my @res = readline(RESULTS);
     close RESULTS;
 
+    if ($args[0] eq 'proc') {
+        # if we see our fakesaslauthd, no we didn't
+        @res = grep { $_ !~ m/\bfakesaslauthd\b/ } @res;
+    }
+
     return @res;
 }
 
diff --git a/cassandane/Cassandane/Instance.pm b/cassandane/Cassandane/Instance.pm
index a9c7f4d98a..00a2964da0 100644
--- a/cassandane/Cassandane/Instance.pm
+++ b/cassandane/Cassandane/Instance.pm
@@ -1200,16 +1200,31 @@ sub start
     }
 
     # arrange for fakesaslauthd to be started by master
-    # XXX make this run as a DAEMON rather than a START
     my $fakesaslauthd_socket = "$self->{basedir}/run/mux";
+    my $fakesaslauthd_isdaemon = 1;
     if ($self->{authdaemon}) {
-        $self->add_start(
-            name => 'fakesaslauthd',
-            argv => [
-                abs_path('utils/fakesaslauthd'),
-                '-p', $fakesaslauthd_socket,
-            ],
-        );
+        my ($maj, $min) = Cassandane::Instance->get_version(
+                            $self->{installation});
+        if ($maj < 3 || ($maj == 3 && $min < 4)) {
+            $self->add_start(
+                name => 'fakesaslauthd',
+                argv => [
+                    abs_path('utils/fakesaslauthd'),
+                    '-p', $fakesaslauthd_socket,
+                ],
+            );
+            $fakesaslauthd_isdaemon = 0;
+        }
+        elsif (not exists $self->{daemons}->{fakesaslauthd}) {
+            $self->add_daemon(
+                name => 'fakesaslauthd',
+                argv => [
+                    abs_path('utils/fakesaslauthd'),
+                    '-p', $fakesaslauthd_socket,
+                ],
+                wait => 'y',
+            );
+        }
     }
 
     if (!$self->{re_use_dir} || ! -d $self->{basedir})
@@ -1243,9 +1258,7 @@ sub start
 
     # give fakesaslauthd a moment (but not more than 2s) to set up its
     # socket before anything starts trying to connect to services
-    # XXX if this were a DAEMON with wait=y, this would be unnecessary,
-    # XXX though those didn't exist until 3.4
-    if ($self->{authdaemon}) {
+    if ($self->{authdaemon} && !$fakesaslauthd_isdaemon) {
         my $tries = 0;
         while (not -S $fakesaslauthd_socket && $tries < 2_000_000) {
             $tries += usleep(10_000); # 10ms as us
diff --git a/cassandane/utils/fakesaslauthd b/cassandane/utils/fakesaslauthd
index 1cdb1a0277..af64fdc68b 100755
--- a/cassandane/utils/fakesaslauthd
+++ b/cassandane/utils/fakesaslauthd
@@ -3,6 +3,7 @@
 # for any user.  Use me for testing!
 
 use Getopt::Std;
+use IO::Handle;
 use IO::Socket::UNIX;
 use Sys::Syslog qw(:standard :macros);
 
@@ -16,13 +17,22 @@ sub get_counted_string
     return unpack("A$size", $data);
 }
 
+# support running as a DAEMON with wait=y:
+# * if fd 3 is already open, then we will need to write to it later to
+#   indicate we're ready.
+# * we must grab this early, before the number gets used for something
+#   else, otherwise we won't be able to differentiate between the fd 3
+#   we care about or some other thing
+# * if fd 3 was not already open, $status_fd will be undef
+my $status_fd = IO::Handle->new_from_fd(3, 'w');
+
 my %opts;
 
 getopts("C:dp:v", \%opts);
 
 die "need a socket path" if not $opts{p};
 
-openlog('fakesaslauthd', '', LOG_LOCAL6)
+openlog('fakesaslauthd', 'pid', LOG_LOCAL6)
     or die "Cannot openlog";
 
 # ok, we're good. background ourselves
@@ -46,6 +56,13 @@ syslog LOG_INFO, "listening on $opts{p}";
 my $shutdown = 0;
 $SIG{HUP} = sub { $shutdown++; };
 
+# okay, now we're ready to accept requests.  inform our parent,
+# if they were waiting to be informed
+if ($ENV{CYRUS_ISDAEMON} && $status_fd) {
+    print $status_fd "ok\r\n";
+    undef $status_fd;
+}
+
 while (my $client = $sock->accept()) {
     my $LoginName = get_counted_string($client);
     my $Password = get_counted_string($client);