Add "make help" option

Based on kubernetes controller Makefile help.

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/20407)

1 files changed, 25 insertions, 0 deletions

diff --git a/util/help.pl b/util/help.pl
new file mode 100755
index 0000000000..a1614fe8a9
--- /dev/null
+++ b/util/help.pl
@@ -0,0 +1,25 @@
+#! /usr/bin/env perl
+# Copyright 2023 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the Apache License 2.0 (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+die "No input files" if scalar @ARGV == 0;
+$FS = ':.*##';
+printf "\nUsage:\n  make <OPTIONS> \033[36m<target>\033[0m\n";
+
+while (<>) {
+    chomp;	# strip record separator
+    @Fld = split($FS, $_, -1);
+    if (/^[a-zA-Z0-9_\-]+:.*?##/) {
+	printf "  \033[36m%-15s\033[0m %s\n", $Fld[0], $Fld[1]
+    }
+    if (/^##@/) {
+	printf "\n\033[1m%s\033[0m\n", substr($Fld[$_], (5)-1);
+    }
+}
+
+printf "\nNote: This list is not all-inclusive\n";
+