test_common: hoist out tail_f sub

We'll be reusing this in more places.  While we're at it, allow
it to tail all run_script() users, including lei() in TestCommon.

1 files changed, 37 insertions, 26 deletions

diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index cd706e0e..57f1db95 100644
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -12,13 +12,14 @@ use IO::Socket::INET;
 use File::Spec;
 our @EXPORT;
 my $lei_loud = $ENV{TEST_LEI_ERR_LOUD};
+my $tail_cmd = $ENV{TAIL};
 our ($lei_opt, $lei_out, $lei_err, $lei_cwdfh);
 BEGIN {
         @EXPORT = qw(tmpdir tcp_server tcp_connect require_git require_mods
                 run_script start_script key2sub xsys xsys_e xqx eml_load tick
                 have_xapian_compact json_utf8 setup_public_inboxes create_inbox
                 tcp_host_port test_lei lei lei_ok $lei_out $lei_err $lei_opt
-                test_httpd xbail require_cmd is_xdeeply);
+                test_httpd xbail require_cmd is_xdeeply tail_f);
         require Test::More;
         my @methods = grep(!/\W/, @Test::More::EXPORT);
         eval(join('', map { "*$_=\\&Test::More::$_;" } @methods));
@@ -280,11 +281,20 @@ sub run_script ($;$$) {
         my $sub = $run_mode == 0 ? undef : key2sub($key);
         my $fhref = [];
         my $spawn_opt = {};
+        my @tail_paths;
         for my $fd (0..2) {
                 my $redir = $opt->{$fd};
                 my $ref = ref($redir);
                 if ($ref eq 'SCALAR') {
-                        open my $fh, '+>', undef or die "open: $!";
+                        my $fh;
+                        if ($tail_cmd && $ENV{TAIL_ALL} && $fd > 0) {
+                                require File::Temp;
+                                $fh = File::Temp->new("fd.$fd-XXXX", TMPDIR=>1);
+                                push @tail_paths, $fh->filename;
+                        } else {
+                                open $fh, '+>', undef;
+                        }
+                        $fh or xbail $!;
                         $fhref->[$fd] = $fh;
                         $spawn_opt->{$fd} = $fh;
                         next if $fd > 0;
@@ -297,6 +307,7 @@ sub run_script ($;$$) {
                         die "unable to deal with $ref $redir";
                 }
         }
+        my $tail = @tail_paths ? tail_f(@tail_paths) : undef;
         if ($key =~ /-(index|convert|extindex|convert|xcpdb)\z/) {
                 unshift @argv, '--no-fsync';
         }
@@ -337,6 +348,7 @@ sub run_script ($;$$) {
                 umask($umask);
         }
 
+        { local $?; undef $tail };
         # slurp the redirects back into user-supplied strings
         for my $fd (1..2) {
                 my $fh = $fhref->[$fd] or next;
@@ -355,13 +367,13 @@ sub tick (;$) {
         1;
 }
 
-sub wait_for_tail ($;$) {
+sub wait_for_tail {
         my ($tail_pid, $want) = @_;
-        my $wait = 2;
+        my $wait = 2; # "tail -F" sleeps 1.0s at-a-time w/o inotify/kevent
         if ($^O eq 'linux') { # GNU tail may use inotify
                 state $tail_has_inotify;
-                return tick if $want < 0 && $tail_has_inotify;
-                my $end = time + $wait;
+                return tick if !$want && $tail_has_inotify; # before TERM
+                my $end = time + $wait; # wait for startup:
                 my @ino;
                 do {
                         @ino = grep {
@@ -410,13 +422,23 @@ sub xqx {
         wantarray ? split(/^/m, $out) : $out;
 }
 
+sub tail_f (@) {
+        $tail_cmd or return; # "tail -F" or "tail -f"
+        for (@_) { open(my $fh, '>>', $_) or die $! };
+        my $cmd = [ split(/ /, $tail_cmd), @_ ];
+        require PublicInbox::Spawn;
+        my $pid = PublicInbox::Spawn::spawn($cmd, undef, { 1 => 2 });
+        wait_for_tail($pid, scalar @_);
+        PublicInboxTestProcess->new($pid, \&wait_for_tail);
+}
+
 sub start_script {
         my ($cmd, $env, $opt) = @_;
         my ($key, @argv) = @$cmd;
         my $run_mode = $ENV{TEST_RUN_MODE} // $opt->{run_mode} // 2;
         my $sub = $run_mode == 0 ? undef : key2sub($key);
-        my $tail_pid;
-        if (my $tail_cmd = $ENV{TAIL}) {
+        my $tail;
+        if ($tail_cmd) {
                 my @paths;
                 for (@argv) {
                         next unless /\A--std(?:err|out)=(.+)\z/;
@@ -434,17 +456,7 @@ sub start_script {
                                 }
                         }
                 }
-                if (@paths) {
-                        $tail_pid = fork // die "fork: $!";
-                        if ($tail_pid == 0) {
-                                # make sure files exist, first
-                                open my $fh, '>>', $_ for @paths;
-                                open(STDOUT, '>&STDERR') or die "1>&2: $!";
-                                exec(split(' ', $tail_cmd), @paths);
-                                die "$tail_cmd failed: $!";
-                        }
-                        wait_for_tail($tail_pid, scalar @paths);
-                }
+                $tail = tail_f(@paths);
         }
         my $pid = fork // die "fork: $!\n";
         if ($pid == 0) {
@@ -480,7 +492,9 @@ sub start_script {
                         die "FAIL: ",join(' ', $key, @argv), ": $!\n";
                 }
         }
-        PublicInboxTestProcess->new($pid, $tail_pid);
+        my $td = PublicInboxTestProcess->new($pid);
+        $td->{-extra} = $tail;
+        $td;
 }
 
 # favor lei() or lei_ok() over $lei for new code
@@ -735,8 +749,8 @@ use strict;
 sub CLONE_SKIP { 1 }
 
 sub new {
-        my ($klass, $pid, $tail_pid) = @_;
-        bless { pid => $pid, tail_pid => $tail_pid, owner => $$ }, $klass;
+        my ($cls, $pid, $cb) = @_;
+        bless { pid => $pid, cb => $cb, owner => $$ }, $cls;
 }
 
 sub kill {
@@ -747,6 +761,7 @@ sub kill {
 sub join {
         my ($self, $sig) = @_;
         my $pid = delete $self->{pid} or return;
+        $self->{cb}->() if defined $self->{cb};
         CORE::kill($sig, $pid) if defined $sig;
         my $ret = waitpid($pid, 0) // die "waitpid($pid): $!";
         $ret == $pid or die "waitpid($pid) != $ret";
@@ -755,10 +770,6 @@ sub join {
 sub DESTROY {
         my ($self) = @_;
         return if $self->{owner} != $$;
-        if (my $tail_pid = delete $self->{tail_pid}) {
-                PublicInbox::TestCommon::wait_for_tail($tail_pid, -1);
-                CORE::kill('TERM', $tail_pid);
-        }
         $self->join('TERM');
 }