Add $config.export() function

This is similar to the config.export variable functionality except it can be
called from within buildfiles.

Note that this function can only be used during configure unless the config
module creation was forced for other meta-operations with config.module=true
in bootstrap.build.

1 files changed, 18 insertions, 30 deletions

diff --git a/libbuild2/config/utility.cxx b/libbuild2/config/utility.cxx
index 355e896..8a99a8b 100644
--- a/libbuild2/config/utility.cxx
+++ b/libbuild2/config/utility.cxx
@@ -18,12 +18,12 @@ namespace build2
   namespace config
   {
     pair<lookup, bool>
-    omitted (scope& r, const variable& var)
+    omitted (scope& rs, const variable& var)
     {
       // This is a stripped-down version of the required() twisted
       // implementation.
 
-      pair<lookup, size_t> org (r.find_original (var));
+      pair<lookup, size_t> org (rs.find_original (var));
 
       bool n (false); // New flag.
       lookup l (org.first);
@@ -35,7 +35,7 @@ namespace build2
 
       if (var.overrides != nullptr)
       {
-        pair<lookup, size_t> ovr (r.find_override (var, move (org)));
+        pair<lookup, size_t> ovr (rs.find_override (var, move (org)));
 
         if (l != ovr.first) // Overriden?
         {
@@ -46,26 +46,25 @@ namespace build2
         }
       }
 
-      if (l.defined () && r.ctx.current_mif->id == configure_id)
-        save_variable (r, var);
+      if (l.defined ())
+        save_variable (rs, var);
 
       return pair<lookup, bool> (l, n);
     }
 
     lookup
-    optional (scope& r, const variable& var)
+    optional (scope& rs, const variable& var)
     {
-      if (r.ctx.current_mif->id == configure_id)
-        save_variable (r, var);
+      save_variable (rs, var);
 
-      auto l (r[var]);
+      auto l (rs[var]);
       return l.defined ()
         ? l
-        : lookup (r.assign (var), var, r); // NULL.
+        : lookup (rs.assign (var), var, rs); // NULL.
     }
 
     bool
-    specified (scope& r, const string& n)
+    specified (scope& rs, const string& n)
     {
       // Search all outer scopes for any value in this namespace.
       //
@@ -75,8 +74,8 @@ namespace build2
       // any original values, they will be "visible"; see find_override() for
       // details.
       //
-      const variable& vns (r.ctx.var_pool.rw (r).insert ("config." + n));
-      for (scope* s (&r); s != nullptr; s = s->parent_scope ())
+      const variable& vns (rs.ctx.var_pool.rw (rs).insert ("config." + n));
+      for (scope* s (&rs); s != nullptr; s = s->parent_scope ())
       {
         for (auto p (s->vars.find_namespace (vns));
              p.first != p.second;
@@ -103,8 +102,7 @@ namespace build2
       const variable& var (
         rs.ctx.var_pool.rw (rs).insert ("config." + n + ".configured"));
 
-      if (rs.ctx.current_mif->id == configure_id)
-        save_variable (rs, var);
+      save_variable (rs, var);
 
       auto l (rs[var]); // Include inherited values.
       return l && !cast<bool> (l);
@@ -118,8 +116,7 @@ namespace build2
       const variable& var (
         rs.ctx.var_pool.rw (rs).insert ("config." + n + ".configured"));
 
-      if (rs.ctx.current_mif->id == configure_id)
-        save_variable (rs, var);
+      save_variable (rs, var);
 
       value& x (rs.assign (var));
 
@@ -133,25 +130,16 @@ namespace build2
     }
 
     void
-    save_variable (scope& r, const variable& var, uint64_t flags)
+    save_variable (scope& rs, const variable& var, uint64_t flags)
     {
-      if (r.ctx.current_mif->id != configure_id)
-        return;
-
-      // The project might not be using the config module. But then how
-      // could we be configuring it? Good question.
-      //
-      if (module* m = r.lookup_module<module> (module::name))
+      if (module* m = rs.lookup_module<module> (module::name))
         m->save_variable (var, flags);
     }
 
     void
-    save_module (scope& r, const char* name, int prio)
+    save_module (scope& rs, const char* name, int prio)
     {
-      if (r.ctx.current_mif->id != configure_id)
-        return;
-
-      if (module* m = r.lookup_module<module> (module::name))
+      if (module* m = rs.lookup_module<module> (module::name))
         m->save_module (name, prio);
     }