# $NetBSD: plist-subst.awk,v 1.2 2006/01/22 16:54:13 jlam Exp $
#
# Copyright (c) 2006 The NetBSD Foundation, Inc.
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#
# This code is derived from software contributed to The NetBSD Foundation
# by Johnny C. Lam.
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###
### Build an array "substitute" of <regexp, value> pairs, that may be used
### to do variable substitutions in PLIST entries.  The variables which
### will be substituted are passed in the environment variable
### PLIST_SUBST_VARS, and the named variables should be found in the
### shell environment.
###
BEGIN {
	PLIST_SUBST_VARS = ENVIRON["PLIST_SUBST_VARS"]

	split(PLIST_SUBST_VARS, vars, " ")
	for (i in vars) {
		value = ENVIRON[vars[i]]
		var = vars[i]
		sub("^PLIST_", "", var)
		regexp = "\\${" var "}"
		substitute[regexp] = value
	}
}

###
### For each entry, replace all ${...} variables with their respective
### values taken from the environment.
###
{
	for (regexp in substitute) {
		gsub(regexp, substitute[regexp])
	}
}