md5, sha1, sha256, sha512: fix link error with partial libcrypto

[gnulib.git] / m4 / gl-openssl.m4

diff --git a/m4/gl-openssl.m4 b/m4/gl-openssl.m4
index f6c55b2..0434c4c 100644 (file)
--- a/m4/gl-openssl.m4
+++ b/m4/gl-openssl.m4
@@ -1,16 +1,31 @@
-# gl-openssl.m4 serial 1
+# gl-openssl.m4 serial 3
 dnl Copyright (C) 2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
+AC_DEFUN([gl_SET_CRYPTO_CHECK_DEFAULT],
+[
+  m4_define([gl_CRYPTO_CHECK_DEFAULT], [$1])
+])
+gl_SET_CRYPTO_CHECK_DEFAULT([no])
+
 AC_DEFUN([gl_CRYPTO_CHECK],
 [
+  dnl gnulib users set this before gl_INIT with gl_SET_CRYPTO_CHECK_DEFAULT()
+  m4_divert_once([DEFAULTS], [with_openssl_default='gl_CRYPTO_CHECK_DEFAULT'])
+
+  dnl Only clear once, so crypto routines can be checked for individually
+  m4_divert_once([DEFAULTS], [LIB_CRYPTO=])
+
   AC_ARG_WITH([openssl],
     [AS_HELP_STRING([--with-openssl],
-      [use libcrypto hash routines if available: default=no])],
+      [use libcrypto hash routines. Valid ARGs are:
+       'yes', 'no', 'auto' => use if available,
+       'optional' => use if available and warn if not available;
+       default is ']gl_CRYPTO_CHECK_DEFAULT['])],
     [],
-    [with_openssl=no])
+    [with_openssl=$with_openssl_default])
 
   if test "x$1" = xMD5; then
     ALG_header=md5.h
@@ -18,16 +33,17 @@ AC_DEFUN([gl_CRYPTO_CHECK],
     ALG_header=sha.h
   fi
 
-  LIB_CRYPTO=
   AC_SUBST([LIB_CRYPTO])
   if test "x$with_openssl" != xno; then
     AC_CHECK_LIB([crypto], [$1],
       [AC_CHECK_HEADERS([openssl/$ALG_header],
-        [LIB_CRYPTO='-lcrypto'
-         AC_DEFINE([HAVE_OPENSSL_$1],[1],
-           [Define to 1 if libcrypto is used for $1])])])
-    if test "x$with_openssl" = xyes; then
-      if test "x$LIB_CRYPTO" = x; then
+         [LIB_CRYPTO=-lcrypto
+          AC_DEFINE([HAVE_OPENSSL_$1], [1],
+            [Define to 1 if libcrypto is used for $1.])])])
+    if test "x$LIB_CRYPTO" = x; then
+      if test "x$with_openssl" = xyes; then
+        AC_MSG_ERROR([openssl development library not found for $1])
+      elif test "x$with_openssl" = xoptional; then
         AC_MSG_WARN([openssl development library not found for $1])
       fi
     fi