Get rid of action rule override semantics

Instead we now have two more or less separate match states for outer and
inner parts of an action.

1 files changed, 156 insertions, 0 deletions

diff --git a/build2/cc/compile-rule.hxx b/build2/cc/compile-rule.hxx
new file mode 100644
index 0000000..6bf63bf
--- /dev/null
+++ b/build2/cc/compile-rule.hxx
@@ -0,0 +1,156 @@
+// file      : build2/cc/compile-rule.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_COMPILE_RULE_HXX
+#define BUILD2_CC_COMPILE_RULE_HXX
+
+#include <libbutl/path-map.mxx>
+
+#include <build2/types.hxx>
+#include <build2/utility.hxx>
+
+#include <build2/rule.hxx>
+#include <build2/filesystem.hxx> // auto_rmfile
+
+#include <build2/cc/types.hxx>
+#include <build2/cc/common.hxx>
+
+namespace build2
+{
+  class depdb;
+
+  namespace cc
+  {
+    // The order is arranged so that their integral values indicate whether
+    // one is a "stronger" than another.
+    //
+    enum class preprocessed: uint8_t {none, includes, modules, all};
+
+    // Positions of the re-exported bmi{}s. See search_modules() for
+    // details.
+    //
+    struct module_positions
+    {
+      size_t start;    // First imported    bmi*{}, 0 if none.
+      size_t exported; // First re-exported bmi*{}, 0 if none.
+      size_t copied;   // First copied-over bmi*{}, 0 if none.
+    };
+
+    class compile_rule: public rule, virtual common
+    {
+    public:
+      compile_rule (data&&);
+
+      virtual bool
+      match (action, target&, const string&) const override;
+
+      virtual recipe
+      apply (action, target&) const override;
+
+      target_state
+      perform_update (action, const target&) const;
+
+      target_state
+      perform_clean (action, const target&) const;
+
+    private:
+      struct match_data;
+      using environment = small_vector<const char*, 2>;
+
+      void
+      append_lib_options (const scope&,
+                          cstrings&,
+                          action,
+                          const target&,
+                          linfo) const;
+
+      void
+      hash_lib_options (const scope&,
+                        sha256&,
+                        action,
+                        const target&,
+                        linfo) const;
+
+      // Mapping of include prefixes (e.g., foo in <foo/bar>) for auto-
+      // generated headers to directories where they will be generated.
+      //
+      // We are using a prefix map of directories (dir_path_map) instead of
+      // just a map in order to also cover sub-paths (e.g., <foo/more/bar> if
+      // we continue with the example). Specifically, we need to make sure we
+      // don't treat foobar as a sub-directory of foo.
+      //
+      // The priority is used to decide who should override whom. Lesser
+      // values are considered higher priority. See append_prefixes() for
+      // details.
+      //
+      // @@ The keys should be normalized.
+      //
+      struct prefix_value
+      {
+        dir_path directory;
+        size_t priority;
+      };
+      using prefix_map = butl::dir_path_map<prefix_value>;
+
+      void
+      append_prefixes (prefix_map&, const target&, const variable&) const;
+
+      void
+      append_lib_prefixes (const scope&,
+                           prefix_map&,
+                           action,
+                           target&,
+                           linfo) const;
+
+      prefix_map
+      build_prefix_map (const scope&, action, target&, linfo) const;
+
+      // Reverse-lookup target type from extension.
+      //
+      const target_type*
+      map_extension (const scope&, const string&, const string&) const;
+
+      pair<auto_rmfile, bool>
+      extract_headers (action, const scope&, file&, linfo,
+                       const file&, const match_data&,
+                       depdb&, bool&, timestamp) const;
+
+      pair<translation_unit, string>
+      parse_unit (action, file&, linfo,
+                  const file&, auto_rmfile&, const match_data&) const;
+
+      void
+      extract_modules (action, const scope&, file&, linfo,
+                       const compile_target_types&,
+                       const file&, match_data&,
+                       module_info&&, depdb&, bool&) const;
+
+      module_positions
+      search_modules (action, const scope&, file&, linfo,
+                      const target_type&,
+                      const file&, module_imports&, sha256&) const;
+
+      const target&
+      make_module_sidebuild (action, const scope&, const target&,
+                             const target&, const string&) const;
+
+      void
+      append_modules (environment&, cstrings&, strings&,
+                      action, const file&, const match_data&) const;
+
+      // Language selection option (for VC) or the value for the -x option.
+      //
+      const char*
+      langopt (const match_data&) const;
+
+      void
+      append_symexport_options (cstrings&, const target&) const;
+
+    private:
+      const string rule_id;
+    };
+  }
+}
+
+#endif // BUILD2_CC_COMPILE_RULE_HXX