From 812b45c66d04648444a9df3944de8e1e94d32180 Mon Sep 17 00:00:00 2001
From: Rovanion Luckey <rovanion.luckey@gmail.com>
Date: Mon, 29 Mar 2021 15:56:25 +0200
Subject: [PATCH 2/3] gnu: Add libmilter.

* gnu/packages/mail.scm (libmilter): New variable. A Sendmail API library for
  building mail filters.
---
 gnu/packages/mail.scm | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/gnu/packages/mail.scm b/gnu/packages/mail.scm
index 8cb548044e..0a6e710611 100644
--- a/gnu/packages/mail.scm
+++ b/gnu/packages/mail.scm
@@ -2869,6 +2869,32 @@ transfer protocols.")
     (license (license:non-copyleft "file://LICENSE"
                                    "See LICENSE in the distribution."))))
 
+(define-public libmilter
+  (package
+    (inherit sendmail)
+    (name "libmilter")
+    (version "1.0.1")
+    (arguments
+     (substitute-keyword-arguments (package-arguments sendmail)
+       ((#:phases phases)
+        `(modify-phases ,phases
+           (replace 'build
+             (lambda* _
+               (with-directory-excursion "libmilter"
+                 (invoke "sh" "Build"))
+               #t))
+           (delete 'pre-install)
+           (replace 'install
+             (lambda* _
+               (with-directory-excursion "libmilter"
+                 (mkdir-p (string-append (assoc-ref %outputs "out") "/lib"))
+                 (invoke "make" "install"))
+               #t))))))
+    (synopsis "Sendmail library for creating mail filters")
+    (description "The Sendmail Mail Filter API (Milter) is designed to allow
+third-party programs access to mail messages as they are being processed in
+order to filter meta-information(headers) and content.")))
+
 (define-public sieve-connect
   (package
     (name "sieve-connect")
-- 
2.30.0