commit b84ff67420c4c7afa2936733cd0c19de0dbeef0b
Author: Heiko Reese <reese@kit.edu>
Date:   Fri Aug 6 23:28:26 2021 +0200

    …

diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..0182df2
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,2 @@
+SUBDIRS = src
+ACLOCAL_AMFLAGS = -I m4
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..5356dd4
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,17 @@
+AC_INIT([exim4_encrypt], [0.1])
+AM_INIT_AUTOMAKE([-Wall -Werror foreign])
+AC_PROG_CC
+AM_PROG_AR
+AC_CONFIG_HEADERS([config.h])
+AC_CONFIG_MACRO_DIRS([m4])
+LT_INIT([shared])
+
+AC_CONFIG_FILES([Makefile
+		 src/Makefile
+])
+
+AC_SEARCH_LIBS([sodium_init], [sodium], [], [
+		AC_MSG_ERROR([unable to find the libsodium library])
+])
+
+AC_OUTPUT
diff --git a/src/Makefile.am b/src/Makefile.am
new file mode 100644
index 0000000..fc4385e
--- /dev/null
+++ b/src/Makefile.am
@@ -0,0 +1,5 @@
+lib_LTLIBRARIES = libexim4encrypt.la
+libexim4encrypt_la_SOURCES = exim4encrypt.c exim4encrypt.h
+libexim4encrypt_la_CPPFLAGS = -I/usr/include/exim4
+libexim4encrypt_la_LDFLAGS = -shared
+include_HEADERS = sodium.h local_scan.h
diff --git a/src/exim4encrypt.c b/src/exim4encrypt.c
new file mode 100644
index 0000000..26e0769
--- /dev/null
+++ b/src/exim4encrypt.c
@@ -0,0 +1,8 @@
+#include "exim4encrypt.h"
+
+__attribute__((constructor)) static void init() {
+    sodium_init();
+}
+
+int dlfunction(uschar **yield, int argc, uschar *argv[]) {
+}
diff --git a/src/exim4encrypt.h b/src/exim4encrypt.h
new file mode 100644
index 0000000..94b2c1a
--- /dev/null
+++ b/src/exim4encrypt.h
@@ -0,0 +1,9 @@
+#include <sodium.h>
+#include <local_scan.h>
+
+#ifndef EXIM_ENCRYPT_LIBRARY_H
+#define EXIM_ENCRYPT_LIBRARY_H
+
+
+#endif //EXIM_ENCRYPT_LIBRARY_H
+