1 files changed, 90 insertions, 0 deletions
diff --git a/build2/config/module.cxx b/build2/config/module.cxx
new file mode 100644
index 0000000..3d03a51
--- /dev/null
+++ b/build2/config/module.cxx
@@ -0,0 +1,90 @@
+// file      : build2/config/module.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2015 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <build2/config/module>
+
+#include <butl/filesystem>
+
+#include <build2/file>
+#include <build2/rule>
+#include <build2/scope>
+#include <build2/diagnostics>
+
+#include <build2/config/operation>
+
+using namespace std;
+using namespace butl;
+
+namespace build2
+{
+  namespace config
+  {
+    //@@ Same as in operation.cxx
+    //
+    static const path config_file ("build/config.build");
+
+    extern "C" void
+    config_boot (scope& root, const location&, unique_ptr<module>&)
+    {
+      tracer trace ("config::boot");
+
+      const dir_path& out_root (root.out_path ());
+      level5 ([&]{trace << "for " << out_root;});
+
+      // Register meta-operations.
+      //
+      root.meta_operations.insert (configure_id, configure);
+      root.meta_operations.insert (disfigure_id, disfigure);
+
+      // Load config.build if one exists.
+      //
+      // Note that we have to do this during bootstrap since the order in
+      // which the modules will be initialized is unspecified. So it is
+      // possible that some module which needs the configuration will get
+      // called first.
+      //
+      path f (out_root / config_file);
+
+      if (file_exists (f))
+        source (f, root, root);
+    }
+
+    extern "C" bool
+    config_init (scope& root,
+                 scope&,
+                 const location& l,
+                 std::unique_ptr<module>&,
+                 bool first,
+                 bool)
+    {
+      tracer trace ("config::init");
+
+      if (!first)
+      {
+        warn (l) << "multiple config module initializations";
+        return true;
+      }
+
+      level5 ([&]{trace << "for " << root.out_path ();});
+
+      // Register alias and fallback rule for the configure meta-operation.
+      //
+      {
+        // We need this rule for out-of-any-project dependencies (e.g.,
+        // libraries imported from /usr/lib).
+        //
+        global_scope->rules.insert<file> (
+          configure_id, 0, "config.file", file_rule::instance);
+
+        auto& r (root.rules);
+
+        r.insert<target> (configure_id, 0, "config", fallback_rule::instance);
+        r.insert<file> (configure_id, 0, "config.file", fallback_rule::instance);
+        r.insert<alias> (configure_id, 0, "config.alias", alias_rule::instance);
+      }
+
+      return true;
+    }
+  }
+}