1 files changed, 88 insertions, 0 deletions
diff --git a/libbuild2/dist/rule.cxx b/libbuild2/dist/rule.cxx
new file mode 100644
index 0000000..357d70e
--- /dev/null
+++ b/libbuild2/dist/rule.cxx
@@ -0,0 +1,88 @@
+// file      : libbuild2/dist/rule.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <libbuild2/dist/rule.hxx>
+
+#include <libbuild2/scope.hxx>
+#include <libbuild2/target.hxx>
+#include <libbuild2/algorithm.hxx>
+#include <libbuild2/diagnostics.hxx>
+
+using namespace std;
+
+namespace build2
+{
+  namespace dist
+  {
+    bool rule::
+    match (action, target&, const string&) const
+    {
+      return true; // We always match.
+    }
+
+    recipe rule::
+    apply (action a, target& t) const
+    {
+      const dir_path& out_root (t.root_scope ().out_path ());
+
+      // If we can, go inside see-through groups.
+      //
+      for (prerequisite_member p:
+             group_prerequisite_members (a, t, members_mode::maybe))
+      {
+        // Note: no exclusion tests, we want all of them (and see also the
+        // dist_include() override).
+
+        // Skip prerequisites imported from other projects.
+        //
+        if (p.proj ())
+          continue;
+
+        // We used to always search and match but that resulted in the
+        // undesirable behavior in case one of the "source" files is
+        // missing. In this case we would enter a target as "output", this
+        // rule would match it, and then dist_execute() would ignore it by
+        // default.
+        //
+        // So now if this is a file target (we still want to always "see
+        // through" other targets like aliases), we will only match it if (1)
+        // it exists in src or (2) it exists as a target. It feels like we
+        // don't need the stronger "... and not implied" condition since if it
+        // is mentioned as a target, then it is in out (we don't do the same
+        // target in both src/out).
+        //
+        // @@ Note that this is still an issue in a custom dist rule.
+        //
+        const target* pt (nullptr);
+        if (p.is_a<file> ())
+        {
+          pt = p.load ();
+
+          if (pt == nullptr)
+          {
+            // Search for an existing target or existing file in src.
+            //
+            const prerequisite_key& k (p.key ());
+            pt = k.tk.type->search (t, k);
+
+            if (pt == nullptr)
+              fail << "prerequisite " << k << " is not existing source file "
+                   << "nor known output target" << endf;
+
+            search_custom (p.prerequisite, *pt); // Cache.
+          }
+        }
+        else
+          pt = &p.search (t);
+
+        // Don't match targets that are outside of our project.
+        //
+        if (pt->dir.sub (out_root))
+          build2::match (a, *pt);
+      }
+
+      return noop_recipe; // We will never be executed.
+    }
+  }
+}