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, 166 insertions, 0 deletions

diff --git a/build2/cc/link-rule.hxx b/build2/cc/link-rule.hxx
new file mode 100644
index 0000000..ba40410
--- /dev/null
+++ b/build2/cc/link-rule.hxx
@@ -0,0 +1,166 @@
+// file      : build2/cc/link-rule.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BUILD2_CC_LINK_RULE_HXX
+#define BUILD2_CC_LINK_RULE_HXX
+
+#include <set>
+
+#include <build2/types.hxx>
+#include <build2/utility.hxx>
+
+#include <build2/rule.hxx>
+
+#include <build2/cc/types.hxx>
+#include <build2/cc/common.hxx>
+
+namespace build2
+{
+  namespace cc
+  {
+    class link_rule: public rule, virtual common
+    {
+    public:
+      link_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:
+      friend class install_rule;
+      friend class libux_install_rule;
+
+      // Shared library paths.
+      //
+      struct libs_paths
+      {
+        // If any (except real) is empty, then it is the same as the next
+        // one. Except for intermediate, for which empty indicates that it is
+        // not used.
+        //
+        // The libs{} path is always the real path. On Windows the link path
+        // is the import library.
+        //
+        path        link;   // What we link: libfoo.so
+        path        soname; // SONAME:       libfoo-1.so, libfoo.so.1
+        path        interm; // Intermediate: libfoo.so.1.2
+        const path* real;   // Real:         libfoo.so.1.2.3
+
+        inline const path&
+        effect_link () const {return link.empty () ? effect_soname () : link;}
+
+        inline const path&
+        effect_soname () const {return soname.empty () ? *real : soname;}
+
+        // Cleanup pattern used to remove previous versions. If empty, no
+        // cleanup is performed. The above (current) names are automatically
+        // filtered out.
+        //
+        path clean;
+      };
+
+      libs_paths
+      derive_libs_paths (file&, const char*, const char*) const;
+
+      struct match_data
+      {
+        // The "for install" condition is signalled to us by install_rule when
+        // it is matched for the update operation. It also verifies that if we
+        // have already been executed, then it was for install.
+        //
+        // This has an interesting implication: it means that this rule cannot
+        // be used to update targets during match. Specifically, we cannot be
+        // executed for group resolution purposes (not a problem) nor as part
+        // of the generated source update. The latter case can be a problem:
+        // imagine a code generator that itself may need to be updated before
+        // it can be used to re-generate some out-of-date source code. As an
+        // aside, note that even if we were somehow able to communicate the
+        // "for install" in this case, the result of such an update may not
+        // actually be "usable" (e.g., not runnable because of the missing
+        // rpaths). There is another prominent case where the result may not
+        // be usable: cross-compilation.
+        //
+        // So the current (admittedly fuzzy) thinking is that a project shall
+        // not try to use its own build for update since it may not be usable
+        // (because of cross-compilations, being "for install", etc). Instead,
+        // it should rely on another, "usable" build of itself (this, BTW, is
+        // related to bpkg's build-time vs run-time dependencies).
+        //
+        optional<bool> for_install;
+
+        libs_paths libs_data;
+      };
+
+      // Library handling.
+      //
+      void
+      append_libraries (strings&,
+                        const file&, bool, lflags,
+                        const scope&, action, linfo) const;
+
+      void
+      hash_libraries (sha256&,
+                      bool&, timestamp,
+                      const file&, bool, lflags,
+                      const scope&, action, linfo) const;
+
+      void
+      rpath_libraries (strings&,
+                       const target&,
+                       const scope&, action, linfo,
+                       bool) const;
+
+      // Windows rpath emulation (windows-rpath.cxx).
+      //
+      struct windows_dll
+      {
+        const string& dll;
+        const string* pdb; // NULL if none.
+        string pdb_storage;
+
+        bool operator< (const windows_dll& y) const {return dll < y.dll;}
+      };
+
+      using windows_dlls = std::set<windows_dll>;
+
+      timestamp
+      windows_rpath_timestamp (const file&,
+                               const scope&,
+                               action, linfo) const;
+
+      windows_dlls
+      windows_rpath_dlls (const file&, const scope&, action, linfo) const;
+
+      void
+      windows_rpath_assembly (const file&, const scope&, action, linfo,
+                              const string&,
+                              timestamp,
+                              bool) const;
+
+      // Windows-specific (windows-manifest.cxx).
+      //
+      pair<path, bool>
+      windows_manifest (const file&, bool rpath_assembly) const;
+
+      // pkg-config's .pc file generation (pkgconfig.cxx).
+      //
+      void
+      pkgconfig_save (action, const file&, bool) const;
+
+    private:
+      const string rule_id;
+    };
+  }
+}
+
+#endif // BUILD2_CC_LINK_RULE_HXX