nagios-plugins/gl/m4/gl-openssl.m4

# gl-openssl.m4 serial 3
dnl Copyright (C) 2013-2015 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. 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=$with_openssl_default])

  if test "x$1" = xMD5; then
    ALG_header=md5.h
  else
    ALG_header=sha.h
  fi

  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 $1.])])])
    if test "x$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
  fi
])