From 5b16a482e4da6e549162ffd9a9e3c9f866a2e8cc Mon Sep 17 00:00:00 2001
From: Ole Tange <github.com@tange.dk>
Date: Tue, 30 Jul 2013 17:13:31 +0200
Subject: [PATCH] src/parallel: Inplemented --linebuffer.

---
 src/parallel | 69 ++++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 59 insertions(+), 10 deletions(-)

diff --git a/src/parallel b/src/parallel
index d6414ac1..da026ab6 100755
--- a/src/parallel
+++ b/src/parallel
@@ -585,6 +585,7 @@ sub options_hash {
 	 "group" => \$opt::group,
 	 "g" => \$opt::retired,
 	 "ungroup|u" => \$opt::u,
+	 "linebuffer|linebuffered|line-buffer|line-buffered" => \$opt::linebuffer,
 	 "null|0" => \$opt::0,
 	 "quote|q" => \$opt::q,
 	 "I=s" => \$opt::I,
@@ -2245,6 +2246,11 @@ sub reap_usleep {
 	return $ms/2+0.001;
     } else {
 	usleep($ms);
+	if($opt::linebuffer) {
+	    for my $job (values %Global::running) {
+		$job->print();
+	    }
+	}
 	# Sleep exponentially longer (1.1^n) if a job did not finish
 	# though at most 1000 ms.
 	return (($ms < 1000) ? ($ms * 1.1) : ($ms));
@@ -4454,7 +4460,10 @@ sub print {
     $Global::grouped or return;
     my $command = $self->sshlogin_wrap();
 
-    if(($opt::dryrun or $Global::verbose) and $Global::grouped) {
+    if(($opt::dryrun or $Global::verbose) and $Global::grouped
+       and
+       not $self->{'verbose_printed'}) {
+	$self->{'verbose_printed'}++;
 	if($Global::verbose <= 1) {
 	    print STDOUT $self->replaced(),"\n";
 	} else {
@@ -4472,21 +4481,61 @@ sub print {
 	my $out_fd = $Global::fd{$fdno};
 	my $in_fd = $self->fd($fdno);
 	if(not $in_fd) {
-#	    ::warning("File descriptor $fdno not defined\n");
+	    if(not $Job::file_descriptor_warning_printed{$fdno}++) {
+		::warning("File descriptor $fdno not defined\n");
+	    }
 	    next;
 	}
-	seek $in_fd, 0, 0;
-	if($Global::debug) {
-	    print STDERR "File descriptor $fdno:\n";
-	}
+	::debug("File descriptor $fdno:");
 	if($opt::files) {
 	    $self->fd_file_name($fdno) and print $out_fd $self->fd_file_name($fdno),"\n";
+	} elsif($opt::linebuffer) {
+	    # Line buffered print out
+	    my $partial = \$self->{'partial_line',$fdno};
+	    # This seek will clear EOF
+	    seek $in_fd, tell($in_fd), 0;
+	    while(read($in_fd,substr($$partial,length $$partial),1_000_000)) {
+		# Append to $$partial
+		# Find the last \n
+		my $i = rindex($$partial,"\n");
+		if($i != -1) {
+		    # One or more complete lines were found
+		    if($fdno == 2 and not $self->{'printed_first_line',$fdno}++) {
+			# OpenSSH_3.6.1p2 gives 'tcgetattr: Invalid argument' with -tt
+			# This is a crappy way of ignoring it.
+			$$partial =~ s/^tcgetattr: Invalid argument\n//;
+			# Length of partial line has changed: Find the last \n again
+			$i = rindex($$partial,"\n");
+		    }
+		    if($opt::tag or defined $opt::tagstring) {
+			# Replace ^ with $tag within the full line
+			my $tag = $self->tag();
+			substr($$partial,0,$i+1) =~ s/^/$tag/gm;
+			# Length of partial line has changed: Find the last \n again
+			$i = rindex($$partial,"\n");
+		    }
+		    # Print up to and including the last \n
+		    print $out_fd substr($$partial,0,$i+1);
+		    # Remove the printed part
+		    substr($$partial,0,$i+1)="";
+		}
+	    }
+
+
+	    if(defined $self->{'exitstatus'} and length $$partial > 0) {
+		# If the job is dead: print the remaining partial line
+		if($opt::tag or defined $opt::tagstring) {
+		    my $tag = $self->tag();
+		    $$partial =~ s/^/$tag/gm;
+		}
+		print $out_fd $$partial;
+		$$partial = undef;
+		# then close fd
+		close $in_fd;
+	    }
 	} else {
 	    my $buf;
 	    seek $in_fd, 0, 0;
-	    if($Global::debug) {
-		print STDOUT "OUT:\n";
-	    }
 	    if($opt::tag or defined $opt::tagstring) {
 		my $tag = $self->tag();
 		if($fdno == 2) {
@@ -4516,10 +4565,10 @@ sub print {
 		    print $out_fd $buf;
 		}
 	    }
+	    close $in_fd;   
 	}
 	flush $out_fd;
 	::debug("<<joboutput $command\n");
-	close $in_fd;
     }
 }