1 files changed, 83 insertions, 0 deletions
diff --git a/libbuild2/rule-adhoc-cxx.hxx b/libbuild2/rule-adhoc-cxx.hxx
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+++ b/libbuild2/rule-adhoc-cxx.hxx
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+// file      : libbuild2/rule-adhoc-cxx.hxx -*- C++ -*-
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef LIBBUILD2_RULE_ADHOC_CXX_HXX
+#define LIBBUILD2_RULE_ADHOC_CXX_HXX
+
+#include <libbuild2/types.hxx>
+#include <libbuild2/forward.hxx>
+#include <libbuild2/utility.hxx>
+
+#include <libbuild2/rule.hxx>
+
+#include <libbuild2/export.hxx>
+
+namespace build2
+{
+  // Ad hoc C++ rule.
+  //
+  // Note: exported but should not be used directly (i.e., registered).
+  //
+  class LIBBUILD2_SYMEXPORT cxx_rule: public rule
+  {
+    // For now this class is provided purely as an alias for rule in case the
+    // implementation (which is also called rule) needs to refer to something
+    // in its base.
+  };
+
+  class LIBBUILD2_SYMEXPORT cxx_rule_v1: public cxx_rule
+  {
+  public:
+    // A robust recipe may want to incorporate the recipe_state into its
+    // up-to-date decision as if the recipe library was a prerequisite (it
+    // cannot be injected as a real prerequisite since it's from a different
+    // build context).
+    //
+    const location     recipe_loc;   // Buildfile location of the recipe.
+    const target_state recipe_state; // State of recipe library target.
+
+    cxx_rule_v1 (const location& l, target_state s)
+      : recipe_loc (l), recipe_state (s) {}
+
+    // Return true by default.
+    //
+    virtual bool
+    match (action, target&, const string&) const override;
+  };
+
+  // Note: not exported.
+  //
+  class adhoc_cxx_rule: public adhoc_rule
+  {
+  public:
+    virtual bool
+    match (action, target&, const string&) const override;
+
+    virtual recipe
+    apply (action, target&) const override;
+
+    adhoc_cxx_rule (const location&, size_t,
+                    uint64_t ver,
+                    optional<string> sep);
+
+    virtual bool
+    recipe_text (context&, const target&, string&& t, attributes&) override;
+
+    virtual
+    ~adhoc_cxx_rule () override;
+
+    virtual void
+    dump_text (ostream&, string&) const override;
+
+  public:
+    // Note that this recipe (rule instance) can be shared between multiple
+    // targets which could all be matched in parallel.
+    //
+    uint64_t                  version;
+    optional<string>          separator;
+    string                    code;
+    mutable atomic<cxx_rule*> impl;
+  };
+}
+
+#endif // LIBBUILD2_RULE_ADHOC_CXX_HXX