1 files changed, 39 insertions, 1 deletions
diff --git a/build/context.txx b/build/context.txx
index 53081b1..218c65e 100644
--- a/build/context.txx
+++ b/build/context.txx
@@ -46,7 +46,7 @@ namespace build
 
   template <typename T>
   fs_status<rmdir_status>
-  rmdir (const path& d, const T& t)
+  rmdir (const dir_path& d, const T& t)
   {
     bool w (d == work); // Don't try to remove working directory.
     rmdir_status rs;
@@ -97,4 +97,42 @@ namespace build
 
     return rs;
   }
+
+  template <typename K>
+  basic_path<char, K>
+  relative (const basic_path<char, K>& p)
+  {
+    typedef basic_path<char, K> path;
+
+    const dir_path& b (*relative_base);
+
+    if (b.empty ())
+      return p;
+
+    if (p.sub (b))
+      return p.leaf (b);
+
+    // If base is a sub-path of {src,out}_root and this path is also a
+    // sub-path of it, then use '..' to form a relative path.
+    //
+    // Don't think this is a good heuristic. For example, why shouldn't
+    // we display paths from imported projects as relative if they are
+    // more readable than absolute?
+    //
+    /*
+    if ((work.sub (src_root) && p.sub (src_root)) ||
+        (work.sub (out_root) && p.sub (out_root)))
+      return p.relative (work);
+    */
+
+    if (p.root_directory () == b.root_directory ())
+    {
+      path r (p.relative (b));
+
+      if (r.string ().size () < p.string ().size ())
+        return r;
+    }
+
+    return p;
+  }
 }