From a83f240ed793e6ae5a27fae75ce029e98e7164d0 Mon Sep 17 00:00:00 2001
From: Eric Loyd <eric@bitnetix.com>
Date: Wed, 7 Aug 2024 13:17:09 -0400
Subject: [PATCH] ENV now supports HOST SERVICE and CONTACT custom macro
 double-decode.

---
 ENV | 78 ++++++++++++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 62 insertions(+), 16 deletions(-)

diff --git a/ENV b/ENV
index e83e1ce..a0e46b5 100755
--- a/ENV
+++ b/ENV
@@ -1,26 +1,32 @@
 #!/bin/bash
 
-varName="novalue"
+varName="servicedesc"
 varDefault=""
-myDelim=" "
+myDelim="[ :-]"
 myField=""
+myHost=""
+myService=""
+myContact=""
+doUpper=""
 
 do_help() {
 cat << HELP_EOF
 This utility is designed to be called by the ARGx parameters of a Nagios configuration as follows:
 
-  \$\$(\$USER1\$/env -n <var> [-t <default>] [-f <field>] [-d <delim>]
+  \$\$(\$USER1\$/env -n <var> [-t <default>] [-f <field>] [-d <delim>] [-u] [-H|-S|-C <suffix>]
 
 Where:
 
-  var     is the name of a NAGIOS_variable (see https://assets.nagios.com/downloads/nagioscore/docs/nagioscore/4/en/macrolist.html) (case insensitive)
-  default is a default value if \$NAGIOS_var\$ is blank (case sensitive)
-  word    is an awk-compatible field number (potentially to use with <delim>)
-  delim   is an awk-compatible field delimiter (defaults to space)
+  var     the name of a case-insensitive NAGIOS_variable (defaults to "servicedesc")
+  default a default value if \$NAGIOS_var\$ is blank (case sensitive)
+  field   an awk-compatible field number (potentially to use with <delim>)
+  delim   an awk-compatible field delimiter (defaults to space, dash, and colon)
+  -u      Convert the output to uppercase (useful for further levels of indirection)
+  suffix  Take var result and use the it to get NAGIOS__[HOST|SERVICE|CONTACT]<result><suffix>
 
 The value will always be trimmed of leading and/or trailing spaces/tabs.
 
-If -f is used, then the result will be as if the request were:
+If -f is used, then the result will be as if the request were as follows, unless the field starts with a negative, in which case it will read from the last word forward:
 
   eche \$NAGIOS_var\$ | awk -F <delim> '{print $<field>}'
 
@@ -32,30 +38,70 @@ Examples:
     Will return "localhost" (or whatever the name of the host is that ran the check)
   .../env -n SERVICESTATE -t 0
     Will return the current state of the service (0, 1, 2) or 0 if the state is not defined
+  .../env -n servicedesc -f 2
+    If the service name is "MySQL Check: myDatabase performance" then it will return "Check" (watch out for defaults!)
+  .../env -n servicedesc -f 4
+    If the service name is "MySQL Check: myDatabase performance" then it will return "myDatabase" (watch out for defaults!)
   .../env -n servicedesc -d : -f 2
-    If the service name is "MySQL Check: myDatabase" then it will return "myDatabase" (trimmed)
+    If the service name is "MySQL Check: myDatabase performance" then it will return "myDatabase performance"
+  .../env -n servicedesc -d : -f -2 
+    If the service name is "MySQL Check: myDatabase performance" then it will return "MySQL Check" (2nd field from right, split by :)*
+  .../env -n servicedesc -f -2 -H pass
+    If the service name is "MySQL Check: myDatabase performance" it will return the value of \$NAGIOS__HOSTNAGIOSXIPASS\$
 
+see https://assets.nagios.com/downloads/nagioscore/docs/nagioscore/4/en/macrolist.html for possible macro names.
+*0 for this field will print the entire line
 HELP_EOF
+  exit
 }
 
 while [ -n "$1" ]; do
   case "$1" in
-    -n) varName=`echo "NAGIOS_$2" | tr "a-z" "A-Z"`; shift 2;;
+    -h|--help) do_help;;
+    -n) varName="$2"; shift 2;;
     -t) varDefault="$2"; shift 2;;
     -d) myDelim="$2"; shift 2;;
     -f) myField="$2"; shift 2;;
+    -H) myHost="$2"; shift 2;;
+    -S) myService="$2"; shift 2;;
+    -C) myContact="$2"; shift 2;;
+    -u) doUpper="true"; shift 1;;
     *) shift 1;;
   esac
 done
 
-# If we don't have a config file, then we don't have variables
-if [ -f "$NAGIOS_MAINCONFIGFILE" ]; then
-  varValue="${!varName}"
-  [ -n "$varValue" -a -n "$myField" ] && varValue=`echo "$varValue" | awk -F "$myDelim" --assign f="$myField" '{print $f}'`
+varName=`echo "NAGIOS_$varName" | tr "a-z" "A-Z"`
+varValue="${!varName}"
+if [ -n "$myField" ]; then
+  if [ "$myField" -lt 0 ]; then
+    varValue=`echo "$varValue" | rev | awk -F "$myDelim" -v f="${myField:1}" '{print $f}' | rev`
+  else
+    varValue=`echo "$varValue" | awk -F "$myDelim" -v f="$myField" '{print $(f)}'`
+  fi
 fi
-[ -z "$varValue" ] && varValue="$varDefault"
 varValue=`echo $varValue | sed -e "s/^[ \t]*//" -e "s/[ \t]*$//"`
-  
+
+[ -n "$doUpper" ] && varValue=`echo "$varValue" | tr "a-z" "A-Z"`
+
+# Check for myHost
+if [ -n "$myHost" ]; then
+  myHost=`echo "NAGIOS__HOST${varValue}${myHost}" | tr "a-z" "A-Z"`
+  varValue=${!myHost}
+fi
+
+# Check for myService
+if [ -n "$myService" ]; then
+  myService=`echo "NAGIOS__SERVICE${varValue}${myService}" | tr "a-z" "A-Z"`
+  varValue=${!myService}
+fi
+
+# Check for myContact
+if [ -n "$myContact" ]; then
+  myContact=`echo "NAGIOS__CONTACT${varValue}${myContact}" | tr "a-z" "A-Z"`
+  varValue=${!myContact}
+fi
+
+[ -z "$varValue" ] && varValue="$varDefault"
 echo "$varValue"
 
 exit 0