[mosh-devel] [PATCH, 2nd attempt] do not treat remote command options as mosh options

[Michael Tokarev]

Currently, mosh treats any arguments that starts with a minus
sign as its options (up to lone "--" which terminates option
processing explicitly), so, for example, the following is not
accepted:

  mosh remotehost uname -r

(mosh treats -r as its option and complains).  But this is very
natural way of specifying remote commands with options -- all
other utilities that spawns other commands -- eg, ssh, strace,
valgrind, chroot, etc -- all stops their option processing once
the command to run is encountered, leaving the rest of the line
to that command.

Do the same in mosh.  In there, we swallow up to two first
non-option args in @argv, and on eating second we reset @ARGV
so that GetOptions() finishes.  After that, we combine our
up to 2 first args in @argv with the rest of @ARGV, if any.

This allwos to specify options after the "mosh" command itself,
or after the hostname to connect to, but everything which is
specified after the remote command to run is not interpreted
by GetOptions() anymore and passed as-is to the remote side.

This may actually break some unusual workarounds of the original
misdesign: construct like

  mosh remotehost uname -- -r

will not work as it works now, because the "--" terminator is
misplaced.  But it is not how mosh command is documented anyway.

Signed-off-by: Michael Tokarev <mjt at tls.msk.ru>
---
 scripts/mosh |   19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/scripts/mosh b/scripts/mosh
index 829c399..ed7e64c 100755
--- a/scripts/mosh
+++ b/scripts/mosh
@@ -80,6 +80,20 @@ sub predict_check {
   }
 }
 
+# options processing.  We recognize our options right after "mosh" command,
+# or after the hostname to connect to (first non-optional argument), but not
+# after the remote command.  Hence we may eat up to 2 non-options in
+# &handle_nonopt(), and skip the rest.
+my @argv;
+sub handle_nonopt() {
+  print "nonopt: @_\n";
+  push @argv, @_;
+  if (scalar @argv == 2) {
+    push @argv, @ARGV;
+    @ARGV = ();
+  }
+}
+Getopt::Long::Configure('permute');
 GetOptions( 'client=s' => \$client,
 	    'server=s' => \$server,
 	    'predict=s' => \$predict,
@@ -90,7 +104,10 @@ GetOptions( 'client=s' => \$client,
 	    'ssh=s' => \$ssh,
 	    'help' => \$help,
 	    'version' => \$version,
-	    'fake-proxy!' => \my $fake_proxy ) or die $usage;
+	    'fake-proxy!' => \my $fake_proxy,
+	    '<>' => \&handle_nonopt ) or die $usage;
+# in case some args remains in @ARGV, join them with @argv.
+ at ARGV = ( @argv, @ARGV );
 
 die $usage if ( defined $help );
 die $version_message if ( defined $version );
-- 
1.7.10