Unittest for sem

doc/FUTURE_IDEAS

@@ -2,10 +2,10 @@
 # sem gzip foo ";" echo done
 
 # Allow 7 to run. After then 7th is started, block untill one is dead
-parallel --mutex uniqidentifier -j7 command
+parallel --semaphore --id uniqidentifier -j7 command
-parallel --automutex  -j7 command
+parallel --semaphore  -j7 command
 mdm.screen find dir -execdir mdm-run cmd {} \;
-find dir -execdir parallel --automutex cmd {} \;
+find dir -execdir parallel --semaphore cmd {} \;
 
 fex syntax for splitting fields
 http://www.semicomplete.com/projects/fex/

src/parallel

@@ -12,6 +12,8 @@ B<parallel> [options] [I<command> [arguments]] B<:::> arguments
 
 B<parallel> [options] [I<command> [arguments]] B<::::> argfile(s)
 
+B<parallel> --semaphore [options] I<command>
+
 =head1 DESCRIPTION
 
 GNU B<parallel> is a shell tool for executing jobs in parallel locally
@@ -342,7 +344,10 @@ use B<-I> instead.
 
 =item B<-P> I<N>
 
-Run up to N jobs in parallel.  0 means as many as possible. Default is 9.
+Run up to N jobs in parallel.  0 means as many as possible. Default is
+9.
+
+If B<--semaphore> is set default is 1 thus making a mutex.
 
 
 =item B<--jobs> I<+N>
@@ -580,6 +585,18 @@ operating system and the B<-s> option.  Pipe the input from /dev/null
 to do anything.
 
 
+=item B<--semaphore> (not implemented)
+
+Work as a counting semaphore. B<--semaphore> will cause GNU
+B<parallel> to start I<command> in the background. When the number of
+simultaneous jobs is reached, GNU B<parallel> will wait for one of
+these to complete before starting another command.
+
+Used with B<--fg> and B<--semaphorename>.
+
+The command B<sem> is an alias for B<parallel --semaphore>.
+
+
 =item B<-S> I<[ncpu/]sshlogin[,[ncpu/]sshlogin[,...]]>
 
 =item B<--sshlogin> I<[ncpu/]sshlogin[,[ncpu/]sshlogin[,...]]>
@@ -784,6 +801,11 @@ To compress all html files using B<gzip> run:
 
 B<find . -name '*.html' | parallel gzip>
 
+If the file names may contain a newline use B<-0>. Substitute FOO BAR with
+FUBAR in all files in this dir and subdirs:
+
+B<find . -type f -print0 | parallel -q0 perl -i -pe 's/FOO BAR/FUBAR/g'>
+
 
 =head1 EXAMPLE: Reading arguments from command line
 

src/sem

@@ -36,7 +36,8 @@ Command to execute. The command may be followed by arguments for the command.
 
 =item B<-j> I<N>
 
-Run up to N commands in parallel. Default is 9.
+Run up to N commands in parallel. Default is 1 thus acting like a
+mutex.
 
 
 =item B<--id> I<id>
@@ -91,21 +92,13 @@ Report bugs to <bug-parallel@gnu.org>.
 
 =head1 AUTHOR
 
-Copyright (C) 2007-10-18 Ole Tange, http://ole.tange.dk
-
-Copyright (C) 2008,2009,2010 Ole Tange, http://ole.tange.dk
-
 Copyright (C) 2010 Ole Tange, http://ole.tange.dk and Free Software
 Foundation, Inc.
 
-Parts of the manual concerning B<xargs> compatibility is inspired by
-the manual of B<xargs> from GNU findutils 4.4.2.
-
-
 
 =head1 LICENSE
 
-Copyright (C) 2007,2008,2009,2010 Free Software Foundation, Inc.
+Copyright (C) 2010 Free Software Foundation, Inc.
 
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
@@ -223,10 +216,9 @@ B<parallel>(1)
 
 =cut
 
+use strict;
 use Symbol qw(gensym);
-#use strict;
 use Getopt::Long;
-use Fcntl 'LOCK_EX', 'LOCK_NB';
 
 Getopt::Long::Configure ("bundling","require_order");
 GetOptions("debug|D" => \$::opt_D,
@@ -241,7 +233,7 @@ $Global::debug = $::opt_D;
 $Global::version = 20100814;
 $Global::progname = 'sem';
 
-my $count = 9; # Default 9
+my $count = 1; # Default 1 = mutex
 if($::opt_count) {
     $count = $::opt_count + 1;
 }
@@ -251,6 +243,9 @@ if($::opt_wait) {
 my $id = $::opt_id;
 my $fg = $::opt_fg || $::opt_wait;
 $::opt_timeout = $::opt_timeout;
+if(defined $::opt_version) {
+    version();
+}
 
 if(not defined $id) {
     # $id = getppid(); 
@@ -312,16 +307,28 @@ sub debug {
     # Returns: N/A
     $Global::debug or return;
     @_ = grep { defined $_ ? $_ : "" } @_;
-    print @_;
+    print map {$_,"\n" } @_;
 }
 
 package Semaphore;
 
+# This package provides a counting semaphore
+#
+# If a process dies without releasing the semaphore the next process
+# that needs that entry will clean up dead semaphores
+#
+# The semaphores are stored in ~/.parallel/semaphores/id-<name> Each
+# file in ~/.parallel/semaphores/id-<name>/ is the process ID of the
+# process holding the entry. If the process dies, the entry can be
+# taken by another process.
+
+use Fcntl qw(:DEFAULT :flock);
+
 sub new {
     my $class = shift;
     my $id = shift;
     my $count = shift;
-    my $parallel_locks = $ENV{'HOME'}."/.parallel/locks";
+    my $parallel_locks = $ENV{'HOME'}."/.parallel/semaphores";
     -d $parallel_locks or mkdir $parallel_locks;
     my $lockdir = "$parallel_locks/$id";
     my $lockfile = $lockdir.".lock";
@@ -408,7 +415,7 @@ sub lock {
     open $self->{'lockfh'}, ">", $self->{'lockfile'}
 	or die "Can't open semaphore file $self->{'lockfile'}: $!";
     chmod 0666, $self->{'lockfile'}; # assuming you want it a+rw
-    while(not flock $self->{'lockfh'}, LOCK_EX|LOCK_NB) {
+    while(not flock $self->{'lockfh'}, LOCK_EX()|LOCK_NB()) {
 	::debug("Cannot lock $self->{'lockfile'}");
 	# TODO if timeout: last
 	sleep 1;

unittest/Start.sh

@@ -3,7 +3,7 @@
 export LANG=C
 SHFILE=/tmp/unittest-parallel.sh
 
-ls -t tests-to-run/test*.sh \
+ls -t tests-to-run/*.sh \
 | perl -pe 's:(.*/(.*)).sh:bash $1.sh > actual-results/$2; diff -Naur wanted-results/$2 actual-results/$2:' \
 >$SHFILE
 

unittest/tests-to-run/sem01.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+echo '### Test mutex. This should take 3 seconds'
+sem 'sleep 1; echo foo'
+sem 'sleep 1; echo foo'
+sem 'sleep 1; echo foo'
+sem --wait
+
+

unittest/wanted-results/sem01

@@ -0,0 +1,4 @@
+### Test mutex. This should take 3 seconds
+foo
+foo
+foo