supporting DOS and fake Unix...

I was very, very, tempted to say "sorry; not supported".  Sadly,
prudence won over juvenile glee...

PS: DOS == dominant operating system

src/lib/Gitolite/Triggers/Shell.pm

@@ -0,0 +1,64 @@
+package Gitolite::Triggers::Shell;
+
+# usage notes: this module must be loaded first in the INPUT trigger list.  Or
+# at least before Mirroring::input anyway.
+
+use Gitolite::Rc;
+use Gitolite::Common;
+
+# fedora likes to do things that are a little off the beaten track, compared
+# to typical gitolite usage:
+# - every user has their own login
+# - the forced command may not get the username as an argument.  If it does
+#   not, the gitolite user name is $USER (the unix user name)
+# - and finally, if the first argument to the forced command is '-s', and
+#   $SSH_ORIGINAL_COMMAND is empty or runs a non-git/gitolite command, then
+#   the user gets a shell
+
+sub input {
+    my $shell_allowed = 0;
+    if ( @ARGV and $ARGV[0] eq '-s' ) {
+        shift @ARGV;
+        $shell_allowed++;
+    }
+
+    @ARGV = ( $ENV{USER} ) unless @ARGV;
+
+    return unless $shell_allowed;
+
+    # now determine if this was intended as a shell command or git/gitolite
+    # command
+
+    my $soc = $ENV{SSH_ORIGINAL_COMMAND};
+
+    # no command, just 'ssh alice@host'; doesn't return ('exec's out)
+    shell_out() if $shell_allowed and not $soc;
+
+    return if git_gitolite_command($soc);
+
+    gl_log( 'shell', $ENV{SHELL}, "-c", $soc );
+    exec $ENV{SHELL}, "-c", $soc;
+}
+
+sub shell_out {
+    my $shell = $ENV{SHELL};
+    $shell =~ s/.*\//-/;    # change "/bin/bash" to "-bash"
+    gl_log( 'shell', $shell );
+    exec { $ENV{SHELL} } $shell;
+}
+
+# some duplication with gitolite-shell, factor it out later, if it works fine
+# for fedora and they like it.
+sub git_gitolite_command {
+    my $soc = shift;
+
+    my $git_commands = "git-upload-pack|git-receive-pack|git-upload-archive";
+    return 1 if $soc =~ /^($git_commands) /;
+
+    my @words = split ' ', $soc;
+    return 1 if $rc{COMMANDS}{ $words[0] };
+
+    return 0;
+}
+
+1;