Rewrite sls(1) in POSIX Awk

1 files changed, 15 insertions, 34 deletions

diff --git a/bin/sls b/bin/sls
index eb376cbc..278d79b4 100755
--- a/bin/sls
+++ b/bin/sls
@@ -1,37 +1,18 @@
-#!/usr/bin/env bash
+#!/usr/bin/awk -f
 
-#
-# sls(1) -- Print all the non-wildcard Host names (first one per line) from
-# an ssh_config(5) file, defaulting to $HOME/.ssh/config.
-#
-# Author: Tom Ryder <tom@sanctum.geek.nz>
-# Copyright: 2014
-# License: Public domain
-#
+# If no arguments, assume the default config files
+BEGIN {
+    if (ARGC == 1) {
+        ARGV[1] = "/etc/ssh/ssh_config"
+        ARGV[2] = ENVIRON["HOME"] "/.ssh/config"
+        ARGC += 2
+    }
+}
 
-# Start by assuming we should parse all hosts
-declare -i sls
-sls=1
+# Manage the processing flag (starts set)
+NR == 1 || /### sls/ { sls = 1 }
+/### nosls/ { sls = 0 }
 
-# Iterate through the config
-while read -r option value _ ; do
-
-    # "### sls" and "### nosls" toggles parsing
-    case $option in
-        '###')
-            case $value in
-                nosls)
-                    sls=0
-                    ;;
-                sls)
-                    sls=1
-                    ;;
-            esac
-            ;;
-        'Host')
-            if ((sls)) && [[ $value != *[^[:alnum:]_-]*  ]] ; then
-                printf '%s\n' "$value"
-            fi
-            ;;
-    esac
-done < "${1:-$HOME/.ssh/config}"
+# If processing flag set, directive is "Host", and hostname has no wildcards,
+# then print it
+sls && $1 == "Host" && $2 !~ /\*/ { print $2 }