configure.ac: Fix AC_ARG_ENABLE/AC_ARG_WITH macros

Multiple tests in configure.ac are flawed:

[--snip--]
    AC_ARG_ENABLE([pthreads],
            [AS_HELP_STRING([--disable-pthreads],
                            [Disable support for pthreads])],
            [pthreads_on=1],
            [pthreads_on=0])
[--snip--]

The third argument is "action-if-given" and the fourth argument
is "action-if-not-given" [0]. Which means that, whether you pass
--enable-pthreads or --disable-pthreads, the third argument will be
executed, that is "pthreads_on=1". And if you pass neither, the fourth
argument will be executed, i.e. "pthreads_on=0".

We want `--enable-pthreads` and `--disable-pthreads` flags to do their job.
The right way to do that will be to eliminate "action-if-given" and replace
the user-defined `FEATURE_on=0|1` shell variables with the `enable_FEATURE`
and `with_PACKAGE` shell variables provided by Autotools.

[0] https://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.69/autoconf.html#Package-Options

Signed-off-by: Aleksandr Makarov <[email protected]>

Author: Aleksandr Makarov

configure.ac

@@ -43,9 +43,9 @@ AM_CONDITIONAL([JAVA_HOME_SET], [test ! -z "$JAVA_HOME"])
 AC_ARG_ENABLE([client-only], 
 	       [AS_HELP_STRING([--enable-client-only],
 			       [Enable the building of only the client mode of libEST])],
-		[clientonly_on=1],
-		[clientonly_on=0])
-AM_CONDITIONAL([ENABLE_CLIENT_ONLY], [test x$clientonly_on = x1])
+		[],
+		[enable_client_only="no"])
+AM_CONDITIONAL([ENABLE_CLIENT_ONLY], [test "$enable_client_only" = "yes"])
 AM_COND_IF([ENABLE_CLIENT_ONLY], 
 	   AC_MSG_RESULT([Client only build enabled])
 	   AC_DEFINE([ENABLE_CLIENT_ONLY]),
@@ -54,9 +54,9 @@ AM_COND_IF([ENABLE_CLIENT_ONLY],
 AC_ARG_ENABLE([brski], 
 	       [AS_HELP_STRING([--enable-brski],
 			       [Enable support for brski bootstrap functionality])],
-		[brski_on=1],
-		[brski_on=0])
-AM_CONDITIONAL([ENABLE_BRSKI], [test x$brski_on = x1])
+		[],
+		[enable_brski="no"])
+AM_CONDITIONAL([ENABLE_BRSKI], [test "$enable_brski" = "yes"])
 AM_COND_IF([ENABLE_BRSKI], 
 	   AC_MSG_RESULT([BRSKI support enabled])
 	   AC_DEFINE([ENABLE_BRSKI]),
@@ -65,9 +65,9 @@ AM_COND_IF([ENABLE_BRSKI],
 AC_ARG_ENABLE([pthreads], 
 	       [AS_HELP_STRING([--disable-pthreads],
 			       [Disable support for pthreads])],
-		[pthreads_on=1],
-		[pthreads_on=0])
-AM_CONDITIONAL([DISABLE_PTHREAD], [test x$pthreads_on = x1])
+		[],
+		[enable_pthreads="yes"])
+AM_CONDITIONAL([DISABLE_PTHREAD], [test "$enable_pthreads" = "no"])
 AM_COND_IF([DISABLE_PTHREAD], 
 	   AC_MSG_RESULT([pthread support disabled])
 	   AC_DEFINE([DISABLE_PTHREADS]), 
@@ -88,13 +88,13 @@ AM_COND_IF([ENABLE_EXAMPLES], AC_MSG_RESULT([yes]), AC_MSG_RESULT([no]))
 AC_ARG_WITH([ssl-dir],
 	    [AS_HELP_STRING([--with-ssl-dir],
 		[location of OpenSSL install folder, defaults to /usr/local/ssl])],
-	    [ssldir="$withval"],
-	    [ssldir="/usr/local/ssl"])
-AC_SUBST([SSL_CFLAGS], "$ssldir/include")
-AC_SUBST([SSL_LDFLAGS], "$ssldir/lib")
+	    [],
+	    [with_ssl_dir="/usr/local/ssl"])
+AC_SUBST([SSL_CFLAGS], "$with_ssl_dir/include")
+AC_SUBST([SSL_LDFLAGS], "$with_ssl_dir/lib")
 
-CFLAGS="$CFLAGS -Wall -I$ssldir/include"
-LDFLAGS="$LDFLAGS -L$ssldir/lib"
+CFLAGS="$CFLAGS -Wall -I$with_ssl_dir/include"
+LDFLAGS="$LDFLAGS -L$with_ssl_dir/lib"
 if test "$is_freebsd" = "1" ; then
 AC_CHECK_LIB([crypto], [EVP_EncryptInit], [],
              [AC_MSG_FAILURE([can't find openssl crypto lib])]
@@ -120,13 +120,13 @@ AC_CHECK_LIB([crypto], [EVP_CIPHER_CTX_reset], [],
 AC_ARG_WITH([libcurl-dir],
  [AS_HELP_STRING([--with-libcurl-dir],
 				 [enable support for client proxy using libcurl])],
- [libcurldir="$withval"],
- [with_libcurldir=no])
+ [],
+ [with_libcurl_dir=no])
 
   AS_IF(
-        [test "x$with_libcurldir" != xno],
-        [[CFLAGS="$CFLAGS -I$libcurldir/include"]
-         [LDFLAGS="$LDFLAGS -L$libcurldir/lib -lcurl"]
+        [test "$with_libcurl_dir" != "no"],
+        [[CFLAGS="$CFLAGS -I$with_libcurl_dir/include"]
+         [LDFLAGS="$LDFLAGS -L$with_libcurl_dir/lib -lcurl"]
          AC_CHECK_LIB(
               [curl],
               [curl_easy_init],
@@ -143,17 +143,17 @@ AC_ARG_WITH([libcurl-dir],
 AC_ARG_WITH([uriparser-dir],
  [AS_HELP_STRING([--with-uriparser-dir],
 				 [enable support for path segments using uriparser])],
- [uriparserdir="$withval"],
- [with_uriparserdir=no])
+ [],
+ [with_uriparser_dir=no])
 
  dnl CFLAGS="$CFLAGS -Wall -I$uriparserdir/include"
  dnl CPPFLAGS="$CPPFLAGS -I$uriparser/include"
  dnl LDFLAGS="$LDFLAGS -L$uriparserdir/lib -luriparser"
 
   AS_IF(
-        [test "x$with_uriparserdir" != xno],
-        [[CFLAGS="$CFLAGS -I$uriparserdir/include"]
-         [LDFLAGS="$LDFLAGS -L$uriparserdir/lib -luriparser"]
+        [test "$with_uriparser_dir" != "no"],
+        [[CFLAGS="$CFLAGS -I$with_uriparser_dir/include"]
+         [LDFLAGS="$LDFLAGS -L$with_uriparser_dir/lib -luriparser"]
          AC_CHECK_LIB(
               [uriparser], 
               [uriParseUriA],
@@ -170,13 +170,13 @@ AC_ARG_WITH([uriparser-dir],
 AC_ARG_WITH([libcoap-dir],
  [AS_HELP_STRING([--with-libcoap-dir],
 				 [enable support for ESToCoAP using libcoap library])],
- [libcoapdir="$withval"],
- [with_libcoapdir=no])          
+ [],
+ [with_libcoap_dir=no])
 
   AS_IF(
-        [test "x$with_libcoapdir" != xno],
-        [[CFLAGS="$CFLAGS -I$libcoapdir/include"]
-         [LDFLAGS="$LDFLAGS -L$libcoapdir/lib -lcoap-2-openssl"]
+        [test "$with_libcoap_dir" != "no"],
+        [[CFLAGS="$CFLAGS -I$with_libcoap_dir/include"]
+         [LDFLAGS="$LDFLAGS -L$with_libcoap_dir/lib -lcoap-2-openssl"]
          AC_CHECK_LIB(
               [coap-2-openssl], 
               [coap_startup],