Add ability to initialize bootstrapped modules after loading root.build

8 files changed, 64 insertions, 34 deletions

diff --git a/libbuild2/config/init.cxx b/libbuild2/config/init.cxx
index 69da09c..df71fae 100644
--- a/libbuild2/config/init.cxx
+++ b/libbuild2/config/init.cxx
@@ -28,7 +28,7 @@ namespace build2
     void
     functions (function_map&); // functions.cxx
 
-    bool
+    void
     boot (scope& rs, const location&, module_boot_extra& extra)
     {
       tracer trace ("config::boot");
@@ -139,7 +139,9 @@ namespace build2
       rs.insert_meta_operation (configure_id, mo_configure);
       rs.insert_meta_operation (disfigure_id, mo_disfigure);
 
-      return true; // Initialize first (load config.build).
+      // Initialize first (load config.build).
+      //
+      extra.init = module_boot_init::before_first;
     }
 
     // host-config.cxx.in
diff --git a/libbuild2/dist/init.cxx b/libbuild2/dist/init.cxx
index a95f768..a96d10e 100644
--- a/libbuild2/dist/init.cxx
+++ b/libbuild2/dist/init.cxx
@@ -22,7 +22,7 @@ namespace build2
   {
     static const rule rule_;
 
-    bool
+    void
     boot (scope& rs, const location&, module_boot_extra& extra)
     {
       tracer trace ("dist::boot");
@@ -74,8 +74,6 @@ namespace build2
       // Create the module.
       //
       extra.set_module (new module (v_d_p));
-
-      return false;
     }
 
     bool
diff --git a/libbuild2/file.cxx b/libbuild2/file.cxx
index 171d136..252f885 100644
--- a/libbuild2/file.cxx
+++ b/libbuild2/file.cxx
@@ -1446,17 +1446,25 @@ namespace build2
     if (scope* rs = root.parent_scope ()->root_scope ())
       load_root (*rs);
 
-    // Finish off initializing bootstrapped modules.
+    // Finish off initializing bootstrapped modules (before mode).
     //
-    for (auto& s: root.root_extra->modules)
+    // Note that init() can load additional modules invalidating iterators.
+    //
+    size_t boot_mods (root.root_extra->modules.size ());
+
+    for (size_t i (0); i != boot_mods; ++i)
     {
-      if (s.boot && s.first)
+      module_state& s (root.root_extra->modules[i]);
+
+      if (s.boot_init && *s.boot_init == module_boot_init::before_first)
         init_module (root, root, s.name, s.loc);
     }
 
-    for (auto& s: root.root_extra->modules)
+    for (size_t i (0); i != boot_mods; ++i)
     {
-      if (s.boot && !s.first)
+      module_state& s (root.root_extra->modules[i]);
+
+      if (s.boot_init && *s.boot_init == module_boot_init::before)
         init_module (root, root, s.name, s.loc);
     }
 
@@ -1482,6 +1490,16 @@ namespace build2
     if (fe) {source_once (p, root, root, f, root);}
     if (he) {p.reset (); source_hooks (p, root, hd, false /* pre */);}
 
+    // Finish off initializing bootstrapped modules (after mode).
+    //
+    for (size_t i (0); i != boot_mods; ++i)
+    {
+      module_state& s (root.root_extra->modules[i]);
+
+      if (s.boot_init && *s.boot_init == module_boot_init::after)
+        init_module (root, root, s.name, s.loc);
+    }
+
     // Print the project configuration report, similar to how we do it in
     // build system modules.
     //
diff --git a/libbuild2/install/init.cxx b/libbuild2/install/init.cxx
index e8ca982..769b106 100644
--- a/libbuild2/install/init.cxx
+++ b/libbuild2/install/init.cxx
@@ -227,7 +227,7 @@ namespace build2
     void
     functions (function_map&); // functions.cxx
 
-    bool
+    void
     boot (scope& rs, const location&, module_boot_extra&)
     {
       tracer trace ("install::boot");
@@ -246,8 +246,6 @@ namespace build2
       rs.insert_operation (install_id,            op_install);
       rs.insert_operation (uninstall_id,          op_uninstall);
       rs.insert_operation (update_for_install_id, op_update_for_install);
-
-      return false;
     }
 
     static const path cmd ("install");
diff --git a/libbuild2/module.cxx b/libbuild2/module.cxx
index bb877d9..02ea64d 100644
--- a/libbuild2/module.cxx
+++ b/libbuild2/module.cxx
@@ -581,7 +581,7 @@ namespace build2
       // The only valid situation here is if the module has already been
       // bootstrapped.
       //
-      assert (i->boot);
+      assert (i->boot_init);
       return;
     }
 
@@ -594,22 +594,22 @@ namespace build2
       fail (loc) << "build system module " << mod << " should not be loaded "
                  << "during bootstrap";
 
-    lm.push_back (module_state {true, false, mod, mf.init, nullptr, loc});
+    lm.push_back (module_state {loc, mod, mf.init, nullptr, nullopt});
     i = lm.end () - 1;
 
     {
-      module_boot_extra e;
+      module_boot_extra e {nullptr, module_boot_init::before};
 
       // Note: boot() can load additional modules invalidating the iterator.
       //
       size_t j (i - lm.begin ());
-      bool f (mf.boot (rs, loc, e));
+      mf.boot (rs, loc, e);
       i = lm.begin () + j;
 
-      i->first = f;
-
       if (e.module != nullptr)
         i->module = move (e.module);
+
+      i->boot_init = e.init;
     }
 
     rs.assign (rs.var_pool ().insert (mod + ".booted")) = true;
@@ -640,7 +640,7 @@ namespace build2
           fail (loc) << "build system module " << mod << " should be loaded "
                      << "during bootstrap";
 
-        lm.push_back (module_state {false, false, mod, mf->init, nullptr, loc});
+        lm.push_back (module_state {loc, mod, mf->init, nullptr, nullopt});
         i = lm.end () - 1;
       }
     }
@@ -648,9 +648,9 @@ namespace build2
     {
       module_state& s (*i);
 
-      if (s.boot)
+      if (s.boot_init)
       {
-        s.boot = false;
+        s.boot_init = nullopt;
         f = true; // This is a first call to init.
       }
     }
diff --git a/libbuild2/module.hxx b/libbuild2/module.hxx
index 0305e2c..4110682 100644
--- a/libbuild2/module.hxx
+++ b/libbuild2/module.hxx
@@ -40,9 +40,27 @@ namespace build2
   // way for us to later pass more information without breaking source
   // compatibility.
   //
+  // By default a booted module is initialized before loading root.build.
+  //
+  // The module should specify the before_first initialization mode if it
+  // should be initialized first (within the resulting two groups the modules
+  // are initializated in the order loaded).
+  //
+  // The module should specify the after initialization mode if it should be
+  // initialized after loading root.build. Note that in this case the module
+  // is also allowed to be initialized explicitly from root.build.
+  //
+  enum class module_boot_init
+  {
+    before_first,
+    before,
+    after
+  };
+
   struct module_boot_extra
   {
     shared_ptr<build2::module> module; // Module instance (out).
+    module_boot_init           init;   // Init mode (out).
 
     // Convenience functions.
     //
@@ -53,11 +71,8 @@ namespace build2
     T& module_as () {assert (module); return static_cast<T&> (*module);}
   };
 
-  // Return true if the module should be initialized first (within the
-  // resulting two groups the modules are initializated in the order loaded).
-  //
   using module_boot_function =
-    bool (scope& root,
+    void (scope& root,
           const location&,
           module_boot_extra&);
 
@@ -122,12 +137,11 @@ namespace build2
   //
   struct module_state
   {
-    bool boot;  // True if the module boot'ed but not yet init'ed.
-    bool first; // True if the boot'ed module must be init'ed first.
+    location_value loc; // Load location.
     const string name;
     module_init_function* init;
     shared_ptr<build2::module> module;
-    location_value loc; // Boot location.
+    optional<module_boot_init> boot_init;
   };
 
   struct module_map: vector<module_state>
diff --git a/libbuild2/test/init.cxx b/libbuild2/test/init.cxx
index b6b18d9..aaacdc6 100644
--- a/libbuild2/test/init.cxx
+++ b/libbuild2/test/init.cxx
@@ -21,7 +21,7 @@ namespace build2
 {
   namespace test
   {
-    bool
+    void
     boot (scope& rs, const location&, module_boot_extra& extra)
     {
       tracer trace ("test::boot");
@@ -112,8 +112,6 @@ namespace build2
       }
 
       extra.set_module (new module (move (d)));
-
-      return false;
     }
 
     bool
diff --git a/libbuild2/version/init.cxx b/libbuild2/version/init.cxx
index 681b6a4..7cb5a48 100644
--- a/libbuild2/version/init.cxx
+++ b/libbuild2/version/init.cxx
@@ -30,7 +30,7 @@ namespace build2
     static const in_rule in_rule_;
     static const manifest_install_rule manifest_install_rule_;
 
-    bool
+    void
     boot (scope& rs, const location& l, module_boot_extra& extra)
     {
       tracer trace ("version::boot");
@@ -279,7 +279,9 @@ namespace build2
                     rewritten,
                     move (ds)));
 
-      return true; // Init first (dist.package, etc).
+      // Initialize first (dist.package, etc).
+      //
+      extra.init = module_boot_init::before_first;
     }
 
     static void