Initial support for ad hoc recipes (still work in progress)

1 files changed, 14 insertions, 5 deletions

diff --git a/libbuild2/context.hxx b/libbuild2/context.hxx
index 573b8d1..2a9c93e 100644
--- a/libbuild2/context.hxx
+++ b/libbuild2/context.hxx
@@ -428,7 +428,7 @@ namespace build2
     //
     const loaded_modules_lock* modules_lock;
 
-    // Nested context for updating build system modules.
+    // Nested context for updating build system modules and ad hoc recipes.
     //
     // Note that such a context itself should normally have modules_context
     // setup to point to itself (see import_module() for details).
@@ -438,9 +438,10 @@ namespace build2
 
   public:
     // If module_context is absent, then automatic updating of build system
-    // modules is disabled. If it is NULL, then the context will be created
-    // lazily if and when necessary. Otherwise, it should be a properly setup
-    // context (including, normally, a self-reference in modules_context).
+    // modules and ad hoc recipes is disabled. If it is NULL, then the context
+    // will be created lazily if and when necessary. Otherwise, it should be a
+    // properly setup context (including, normally, a self-reference in
+    // modules_context).
     //
     explicit
     context (scheduler&,
@@ -553,9 +554,17 @@ namespace build2
   // Assuming we have a lock on the current phase, temporarily switch to a
   // new phase and switch back on destruction.
   //
+  // The second constructor can be used for a switch with an intermittent
+  // unlock:
+  //
+  // phase_unlock pu;
+  // phase_lock pl;
+  // phase_switch ps (move (pu), move (pl));
+  //
   struct LIBBUILD2_SYMEXPORT phase_switch
   {
-    explicit phase_switch (context&, run_phase);
+    phase_switch (context&, run_phase);
+    phase_switch (phase_unlock&&, phase_lock&&);
     ~phase_switch () noexcept (false);
 
     run_phase old_phase, new_phase;