configure.in: Correct the `--enable-<plugin>' code.

The new behavior is documented in the `README' file, too.

diff --git a/README b/README
index 904e7c7..97b66f7 100644 (file)
--- a/README
+++ b/README
@@ -389,9 +389,11 @@ Configuring / Compiling / Installing
   disable all plugins whose requirements cannot be fulfilled (any other plugin
   will be enabled). To enable a plugin, install missing dependencies (see
   section `Prerequisites' above) and rerun `configure'. If you specify the
-  `--enable-<plugin>' configure option, you can force the plugin to be built.
-  This will most likely fail though unless you're working in a very unusual
-  setup and you really know what you're doing.
+  `--enable-<plugin>' configure option, the script will fail if the depen-
+  dencies for the specified plugin are not met. If you specify the
+  `--disable-<plugin>' configure option, the plugin will not be built. Both
+  options are meant for package maintainers and should not be used in everyday
+  situations.
 
   By default, collectd will be installed into `/opt/collectd'. You can adjust
   this setting by specifying the `--prefix' configure option - see INSTALL for

diff --git a/configure.in b/configure.in
index 88b13da..bc4d321 100644 (file)
--- a/configure.in
+++ b/configure.in
@@ -2276,12 +2276,15 @@ AC_DEFUN(
             enable_plugin="no"
      fi
     ])
-    if test "x$enable_plugin" = "xyes" && test "x$2" = "xyes"
+    if test "x$enable_plugin" = "xyes"
     then
-           AC_DEFINE([HAVE_PLUGIN_]my_toupper([$1]), 1, [Define to 1 if the $1 plugin is enabled.])
-    else
-           dependency_error="yes"
-           test "x$enable_plugin" = "xyes" && enable_plugin="failed (missing dependency)"
+           if test "x$2" = "xyes"
+           then
+                   AC_DEFINE([HAVE_PLUGIN_]my_toupper([$1]), 1, [Define to 1 if the $1 plugin is enabled.])
+           else # User passed "yes" but dependency checking yielded "no" => Dependency problem.
+                   dependency_error="yes"
+                   enable_plugin="no (dependency error)"
+           fi
     fi
     AM_CONDITIONAL([BUILD_PLUGIN_]my_toupper([$1]), test "x$enable_plugin" = "xyes")
     enable_$1="$enable_plugin"