lei q: support reading queries from stdin

This will be useful on shared machines when a user doesn't want
search queries visible to other users looking at the ps(1)
output or similar.

7 files changed, 88 insertions, 11 deletions

diff --git a/MANIFEST b/MANIFEST
index bcb9d08e..6922f9b1 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -173,6 +173,7 @@ lib/PublicInbox/In2Tie.pm
 lib/PublicInbox/Inbox.pm
 lib/PublicInbox/InboxIdle.pm
 lib/PublicInbox/InboxWritable.pm
+lib/PublicInbox/InputPipe.pm
 lib/PublicInbox/Isearch.pm
 lib/PublicInbox/KQNotify.pm
 lib/PublicInbox/LEI.pm
diff --git a/lib/PublicInbox/InputPipe.pm b/lib/PublicInbox/InputPipe.pm
new file mode 100644
index 00000000..a8bdf031
--- /dev/null
+++ b/lib/PublicInbox/InputPipe.pm
@@ -0,0 +1,37 @@
+# Copyright (C) 2021 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+
+# for reading pipes and sockets off the DS event loop
+package PublicInbox::InputPipe;
+use strict;
+use v5.10.1;
+use parent qw(PublicInbox::DS);
+use PublicInbox::Syscall qw(EPOLLIN EPOLLET);
+
+sub consume {
+        my ($in, $cb, @args) = @_;
+        my $self = bless { cb => $cb, sock => $in, args => \@args },__PACKAGE__;
+        if ($PublicInbox::DS::in_loop) {
+                eval { $self->SUPER::new($in, EPOLLIN|EPOLLET) };
+                return $in->blocking(0) unless $@; # regular file sets $@
+        }
+        event_step($self) while $self->{sock};
+}
+
+sub event_step {
+        my ($self) = @_;
+        my ($r, $rbuf);
+        while (($r = sysread($self->{sock}, $rbuf, 65536))) {
+                $self->{cb}->(@{$self->{args} // []}, $rbuf);
+        }
+        if (defined($r)) { # EOF
+                $self->{cb}->(@{$self->{args} // []}, '');
+        } elsif ($!{EAGAIN}) {
+                return;
+        } else {
+                $self->{cb}->(@{$self->{args} // []}, undef)
+        }
+        $self->{sock}->blocking ? delete($self->{sock}) : $self->close
+}
+
+1;
diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index 28dce0c5..49deed13 100644
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -101,10 +101,10 @@ sub _config_path ($) {
 # TODO: generate shell completion + help using %CMD and %OPTDESC
 # command => [ positional_args, 1-line description, Getopt::Long option spec ]
 our %CMD = ( # sorted in order of importance/use:
-'q' => [ 'SEARCH_TERMS...', 'search for messages matching terms', qw(
+'q' => [ '--stdin|SEARCH_TERMS...', 'search for messages matching terms', qw(
         save-as=s output|mfolder|o=s format|f=s dedupe|d=s thread|t augment|a
         sort|s=s reverse|r offset=i remote! local! external! pretty
-        include|I=s@ exclude=s@ only=s@ jobs|j=s globoff|g
+        include|I=s@ exclude=s@ only=s@ jobs|j=s globoff|g stdin|
         mua-cmd|mua=s no-torsocks torsocks=s verbose|v quiet|q
         received-after=s received-before=s sent-after=s sent-since=s),
         PublicInbox::LeiQuery::curl_opt(), opt_dash('limit|n=i', '[0-9]+') ],
@@ -554,12 +554,13 @@ sub optparse ($$$) {
                 } elsif ($var =~ /\A\[-?$POS_ARG\]\z/) { # one optional arg
                         $i++;
                 } elsif ($var =~ /\A.+?\|/) { # required FOO|--stdin
+                        $inf = 1 if index($var, '...') > 0;
                         my @or = split(/\|/, $var);
                         my $ok;
                         for my $o (@or) {
                                 if ($o =~ /\A--([a-z0-9\-]+)/) {
                                         $ok = defined($OPT->{$1});
-                                        last;
+                                        last if $ok;
                                 } elsif (defined($argv->[$i])) {
                                         $ok = 1;
                                         $i++;
diff --git a/lib/PublicInbox/LeiOverview.pm b/lib/PublicInbox/LeiOverview.pm
index 88034ada..e33d63a2 100644
--- a/lib/PublicInbox/LeiOverview.pm
+++ b/lib/PublicInbox/LeiOverview.pm
@@ -81,7 +81,6 @@ sub new {
         my ($isatty, $seekable);
         if ($dst eq '/dev/stdout') {
                 $isatty = -t $lei->{1};
-                $lei->start_pager if $isatty;
                 $opt->{pretty} //= $isatty;
                 if (!$isatty && -f _) {
                         my $fl = fcntl($lei->{1}, F_GETFL, 0) //
diff --git a/lib/PublicInbox/LeiQuery.pm b/lib/PublicInbox/LeiQuery.pm
index 8015ecec..4fe40400 100644
--- a/lib/PublicInbox/LeiQuery.pm
+++ b/lib/PublicInbox/LeiQuery.pm
@@ -12,6 +12,16 @@ sub prep_ext { # externals_each callback
         $lxs->prepare_external($loc) unless $exclude->{$loc};
 }
 
+sub qstr_add { # for --stdin
+        my ($self) = @_; # $_[1] = $rbuf
+        if (defined($_[1])) {
+                return eval { $self->{lxs}->do_query($self) } if $_[1] eq '';
+                $self->{mset_opt}->{qstr} .= $_[1];
+        } else {
+                $self->fail("error reading stdin: $!");
+        }
+}
+
 # the main "lei q SEARCH_TERMS" method
 sub lei_q {
         my ($self, @argv) = @_;
@@ -84,12 +94,6 @@ sub lei_q {
         my %mset_opt = map { $_ => $opt->{$_} } qw(thread limit offset);
         $mset_opt{asc} = $opt->{'reverse'} ? 1 : 0;
         $mset_opt{limit} //= 10000;
-        $mset_opt{qstr} = join(' ', map {;
-                # Consider spaces in argv to be for phrase search in Xapian.
-                # In other words, the users should need only care about
-                # normal shell quotes and not have to learn Xapian quoting.
-                /\s/ ? (s/\A(\w+:)// ? qq{$1"$_"} : qq{"$_"}) : $_
-        } @argv);
         if (defined(my $sort = $opt->{'sort'})) {
                 if ($sort eq 'relevance') {
                         $mset_opt{relevance} = 1;
@@ -104,7 +108,21 @@ sub lei_q {
         # descending docid order
         $mset_opt{relevance} //= -2 if $opt->{thread};
         $self->{mset_opt} = \%mset_opt;
-        $self->{ovv}->ovv_begin($self);
+
+        if ($opt->{stdin}) {
+                return $self->fail(<<'') if @argv;
+no query allowed on command-line with --stdin
+
+                require PublicInbox::InputPipe;
+                PublicInbox::InputPipe::consume($self->{0}, \&qstr_add, $self);
+                return;
+        }
+        # Consider spaces in argv to be for phrase search in Xapian.
+        # In other words, the users should need only care about
+        # normal shell quotes and not have to learn Xapian quoting.
+        $mset_opt{qstr} = join(' ', map {;
+                /\s/ ? (s/\A(\w+:)// ? qq{$1"$_"} : qq{"$_"}) : $_
+        } @argv);
         $lxs->do_query($self);
 }
 
diff --git a/lib/PublicInbox/LeiXSearch.pm b/lib/PublicInbox/LeiXSearch.pm
index d33064bb..965617b5 100644
--- a/lib/PublicInbox/LeiXSearch.pm
+++ b/lib/PublicInbox/LeiXSearch.pm
@@ -402,6 +402,8 @@ sub sigpipe_handler { # handles SIGPIPE from l2m/lxs workers
 sub do_query {
         my ($self, $lei) = @_;
         $lei->{1}->autoflush(1);
+        $lei->start_pager if -t $lei->{1};
+        $lei->{ovv}->ovv_begin($lei);
         my ($au_done, $zpipe);
         my $l2m = $lei->{l2m};
         if ($l2m) {
diff --git a/t/lei.t b/t/lei.t
index 03bbb078..01eed1da 100644
--- a/t/lei.t
+++ b/t/lei.t
@@ -275,6 +275,25 @@ my $test_external = sub {
         my $pretty = $json->decode($out);
         is_deeply($res, $pretty, '--pretty is identical after decode');
 
+        {
+                open my $fh, '+>', undef or BAIL_OUT $!;
+                $fh->autoflush(1);
+                print $fh 's:use' or BAIL_OUT $!;
+                seek($fh, 0, SEEK_SET) or BAIL_OUT $!;
+                ok($lei->([qw(q -q --stdin)], undef, { %$opt, 0 => $fh }),
+                                '--stdin on regular file works');
+                like($out, qr/use boolean prefix/, '--stdin on regular file');
+        }
+        {
+                pipe(my ($r, $w)) or BAIL_OUT $!;
+                print $w 's:use' or BAIL_OUT $!;
+                close $w or BAIL_OUT $!;
+                ok($lei->([qw(q -q --stdin)], undef, { %$opt, 0 => $r }),
+                                '--stdin on pipe file works');
+                like($out, qr/use boolean prefix/, '--stdin on pipe');
+        }
+        ok(!$lei->(qw(q -q --stdin s:use)), "--stdin and argv don't mix");
+
         for my $fmt (qw(ldjson ndjson jsonl)) {
                 $lei->('q', '-f', $fmt, 's:use boolean prefix');
                 is($out, $json->encode($pretty->[0])."\n", "-f $fmt");