use restart, kill-timeout=0, return all group info

config/github302-perlre-server2.bash

@@ -0,0 +1,59 @@
+# ble.sh contrib/config/github302-perlre-server2.bash
+# Copyright 2023 Britton Kerin <https://lists.gnu.org/archive/html/help-bash/2023-03/msg00068.html>
+# Copyright 2023 Koichi Murase <[email protected]>
+
+# This module implements an interface to a perl regex server (a background
+# process which waits to perform regex matches without the overhead of
+# starting a perl interpreter each time).
+
+ble-import util.bgproc
+
+function ble/contrib/config:github302/perlre-server2 {
+  exec perl "${BASH_SOURCE%.bash}.pl"
+}
+
+# restart so user can easily try again if they send a bad regex.
+# kill-timeout=0 because on some terminals ble.sh will end up exiting slowly
+# if we wait before sending SIGTERM.  FIXXME: using deferred here would
+# reduce the start-up time cost a tiny bit but then the startup message
+# could be disruptive, and I think they're more valuable at the moment
+if ble/util/bgproc#open perlre_server2 ble/contrib/config:github302/perlre-server2 restart:kill-timeout=0; then
+  # The main shell can send a request to fd ${perlre_server2_bgproc[1]} and can
+  # read from fd ${perlre_server2_bgproc[0]}.
+  ble/util/print "ble/contrib/config:github30: perlre-server2 (${perlre_server2_bgproc[4]}) has started." >&2
+else
+  ble/util/print 'ble/contrib/config:github30: failed to start perlre-server2' >&2
+  return 1
+fi
+
+## @fn ble/contrib/config:github302/perlre-match2 rex str
+##
+##   Matches the regex REX against the string STR
+##
+##   @param[in] rex
+##     The regex to match in "perlre" syntax.   Must be exactly one line long.
+##   @param[in] str
+##     The string to be matched by REX.  May be multiple lines.
+##   @var[out] ret
+##     A blank line if the match failed, otherwise a single line of the form:
+##       epm eps eml g1m g1s g1l g2m g2s g2l ...
+##     where epm/eps/epl are Entire Pattern Matched (1)/Start/Length and
+##     g1m/g1s/g1l are (capture) Group 1 Matched (0 or 1)/Start/Lengh, etc.
+##     (where Start/Length may be 'undef').  Note that epm is always 1 here
+##     since we return an empty line if the match fails.
+##   @exit 0 if REX successfully matches STR, or otherwise 1.
+##
+function ble/contrib/config:github302/perlre-match2 {
+
+  ble/util/bgproc#use perlre_server2
+
+  local tmp=${2//[!$'\n']}
+  ble/util/print-lines "$1" "$((${#tmp} + 1))" "$2" >&"${perlre_server2_bgproc[1]}"
+
+  # We can read the responses from fd ${perlre_server2_bgproc[0]}.  We set a
+  # timeout to `read' so that it doesn't lock forever in case that the expected
+  # output is not obtained by accident.
+  ble/bash/read-timeout 1 -r -u "${perlre_server2_bgproc[0]}" ret
+
+  [[ $ret ]]
+}

config/github302-perlre-server2.pl

@@ -0,0 +1,67 @@
+#!/usr/bin/perl -w
+
+use strict;
+use warnings FATAL => 'all';
+use 5.10.0;
+
+#use Data::Dumper;
+
+STDOUT->autoflush(1);
+STDERR->autoflush(1);
+
+# ble.sh is eating STDERR at this point so to get feedback we do this:
+$SIG{__WARN__} = sub {
+  print STDERR "in perlre-server2 bgproc: ".$_[0];
+};
+$SIG{__DIE__}  = sub {
+  print STDERR "in perlre-server2 bgproc: ".$_[0]; exit 1;
+};
+
+my $mlf = undef;   # My Log File (leave undef to disable logging)
+#open($mlf, ">>/tmp/mlf") or die; $mlf->autoflush(1);
+
+while ( 1 ) {
+
+  # First line is regex
+  chomp(my $rex = <>);
+  defined($rex) or exit;   # undef might mean end of pipe.  I think
+  defined($mlf) and print $mlf "from perl: \$rex: $rex\n";
+
+  # Next line is number of lines in string to match
+  chomp(my $lc = <>);
+  defined($lc) or exit;    # undef might mean end of pipe.  I think
+  defined($mlf) and print $mlf "from perl: \$lc: $lc\n";
+
+  # Remaining input lines are the input string
+  my $str = '';
+  for ( my $ii = 0 ; $ii < $lc ; $ii++ ) {   # Get Lines
+    my $nsl = <>;            # New String Line
+    defined($nsl) or exit;   # undef might mean end of pipe.  I think
+    $str .= $nsl;
+  }
+  chomp($str);   # Remove trailing "\n" of last line
+  defined($mlf) and print $mlf "from perl: \$str: $str\n";
+
+  # Respond with blank line if the match fails, otherwise with a single
+  # line of the form:
+  #
+  #    epm eps epl g1m g1s g1l g2m g2s g2l ...
+  #
+  # where epm/eps/epl are Entire Pattern Matched (1)/Start/Length and
+  # g1m/g1s/g1l are (capture) Group 1 Matched (0 or 1)/Start/Lengh, etc.
+  # (where Start/Length may be 'undef').  Note that epm is always 1 since
+  # we return an empty line if the match fails.
+  if ( $str =~ m/$rex/ ) {
+    print
+      join(
+        ' ',
+        map {
+          defined($+[$_])
+          ? "1 $-[$_] ".($+[$_] - $-[$_])
+          : '0 undef undef'
+        }
+        (0 .. $#+) );
+  }
+  print "\n";
+
+}