Use path_name_view in location and path_name_value in location_value

11 files changed, 126 insertions, 36 deletions

diff --git a/build2/b.cxx b/build2/b.cxx
index 486b44c..b7e534e 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -741,7 +741,7 @@ main (int argc, char* argv[])
       }
 
       const path p ("<buildspec>");
-      const location l (&p, 0, 0); //@@ TODO
+      const location l (p, 0, 0); //@@ TODO
 
       meta_operation_id mid (0); // Not yet translated.
       const meta_operation_info* mif (nullptr);
diff --git a/libbuild2/cc/parser.cxx b/libbuild2/cc/parser.cxx
index 706dc48..45120e2 100644
--- a/libbuild2/cc/parser.cxx
+++ b/libbuild2/cc/parser.cxx
@@ -197,7 +197,7 @@ namespace build2
       // enter: module keyword
       // leave: semi
 
-      location l (get_location (t));
+      location_value l (get_location (t));
 
       l_->next (t);
 
@@ -208,7 +208,7 @@ namespace build2
       //
       if (!ex && t.type == type::semi)
       {
-        module_marker_ = location_value (move (l));
+        module_marker_ = move (l);
         return;
       }
 
diff --git a/libbuild2/config/init.cxx b/libbuild2/config/init.cxx
index c9c6130..d48e0a8 100644
--- a/libbuild2/config/init.cxx
+++ b/libbuild2/config/init.cxx
@@ -242,7 +242,7 @@ namespace build2
         {
           for (const path& f: cast<paths> (l))
           {
-            location l (&f);
+            location l (f);
 
             const string& s (f.string ());
 
diff --git a/libbuild2/diagnostics.hxx b/libbuild2/diagnostics.hxx
index 4b3af4e..6a37561 100644
--- a/libbuild2/diagnostics.hxx
+++ b/libbuild2/diagnostics.hxx
@@ -300,7 +300,7 @@ namespace build2
     location_prologue_base (const char* type,
                             const char* mod,
                             const char* name,
-                            const path_name& f,
+                            const path_name_view& f,
                             stream_verbosity sverb)
         : type_ (type), mod_ (mod), name_ (name),
           loc_ (f),
@@ -312,7 +312,7 @@ namespace build2
                             path&& f,
                             stream_verbosity sverb)
         : type_ (type), mod_ (mod), name_ (name),
-          file_ (move (f)), loc_ (&file_),
+          file_ (move (f)), loc_ (file_),
           sverb_ (sverb) {}
 
     void
@@ -367,6 +367,18 @@ namespace build2
       return location_prologue (epilogue_, type_, mod_, name_, f, sverb_ ());
     }
 
+    location_prologue
+    operator() (const path_name_view& f) const
+    {
+      return location_prologue (epilogue_, type_, mod_, name_, f, sverb_ ());
+    }
+
+    location_prologue
+    operator() (const path_name_value& f) const
+    {
+      return location_prologue (epilogue_, type_, mod_, name_, f, sverb_ ());
+    }
+
     // fail (relative (src)) << ...
     //
     location_prologue
diff --git a/libbuild2/dist/operation.cxx b/libbuild2/dist/operation.cxx
index eb7cce1..12ae464 100644
--- a/libbuild2/dist/operation.cxx
+++ b/libbuild2/dist/operation.cxx
@@ -144,7 +144,8 @@ namespace build2
       // since the meta operation is dist and we know what we are doing.
       //
       values params;
-      const location loc (path_name ("<dist>")); // Dummy location.
+      path_name pn ("<dist>");
+      const location loc (pn); // Dummy location.
 
       const operations& ops (rs->root_extra->operations);
 
diff --git a/libbuild2/in/rule.cxx b/libbuild2/in/rule.cxx
index de7ad88..593fb6d 100644
--- a/libbuild2/in/rule.cxx
+++ b/libbuild2/in/rule.cxx
@@ -221,7 +221,7 @@ namespace build2
               // can be overriden with custom substitution semantics.
               //
               optional<string> v (
-                substitute (location (&ip, ln), a, t, n, strict));
+                substitute (location (ip, ln), a, t, n, strict));
 
               assert (v); // Rule semantics change without version increment?
 
@@ -302,7 +302,7 @@ namespace build2
 
           // Not tracking column for now (see also depdb above).
           //
-          const location l (&ip, ln);
+          const location l (ip, ln);
 
           // Scan the line looking for substiutions in the $<name>$ form. In
           // the strict mode treat $$ as an escape sequence.
diff --git a/libbuild2/types.hxx b/libbuild2/types.hxx
index 8566c50..b76bbb4 100644
--- a/libbuild2/types.hxx
+++ b/libbuild2/types.hxx
@@ -228,6 +228,7 @@ namespace build2
   //
   using butl::path;
   using butl::path_name;
+  using butl::path_name_view;
   using butl::path_name_value;
   using butl::dir_path;
   using butl::path_cast;
@@ -311,26 +312,37 @@ namespace build2
 
   // Diagnostics location.
   //
-  // Note that location maintains a shallow reference to path. Zero lines or
-  // columns are not printed.
+  // Note that location maintains a shallow reference to path/path_name. Zero
+  // lines or columns are not printed.
   //
   class location
   {
   public:
+    path_name_view file;
+    uint64_t       line;
+    uint64_t       column;
+
+    location (): line (0), column (0) {}
+
+    explicit
+    location (const path& f, uint64_t l = 0, uint64_t c = 0)
+        : file (&f, nullptr /* name */), line (l), column (c) {}
+
     explicit
-    location (const path* f = nullptr, uint64_t l = 0, uint64_t c = 0)
+    location (path&&, uint64_t = 0, uint64_t = 0) = delete;
+
+    explicit
+    location (const path_name_view& f, uint64_t l = 0, uint64_t c = 0)
         : file (f), line (l), column (c) {}
 
     explicit
-    location (path_name f, uint64_t l = 0, uint64_t c = 0)
-        : file (std::move (f)), line (l), column (c) {}
+    location (path_name_view&&, uint64_t = 0, uint64_t = 0) = delete;
 
     bool
-    empty () const {return file.empty ();}
+    empty () const {return file.null () || file.empty ();}
 
-    path_name file;
-    uint64_t  line;
-    uint64_t  column;
+  protected:
+    location (uint64_t l, uint64_t c): line (l), column (c) {}
   };
 
   // Similar (and implicit-convertible) to the above but stores a copy of the
@@ -339,19 +351,17 @@ namespace build2
   class location_value: public location
   {
   public:
-    location_value () = default;
+    path_name_value file;
 
-    explicit
-    location_value (const location& l)
-        : location (path_name (file_value, l.file.name), l.line, l.column),
-          file_value (l.file.path != nullptr ? *l.file.path : path ()) {}
+    location_value ();
 
     explicit
-    location_value (location&& l)
-        : location (path_name (file_value, move (l.file.name)), l.line, l.column),
-          file_value (l.file.path != nullptr ? *l.file.path : path ()) {}
+    location_value (const location&);
 
-    path file_value;
+    location_value (location_value&&);
+    location_value (const location_value&);
+    location_value& operator= (location_value&&);
+    location_value& operator= (const location_value&);
   };
 
   // See context.
@@ -375,7 +385,7 @@ namespace std
   operator<< (ostream&, const ::butl::path&);
 
   LIBBUILD2_SYMEXPORT ostream&
-  operator<< (ostream&, const ::butl::path_name&);
+  operator<< (ostream&, const ::butl::path_name_view&);
 
   // Print as recall[@effect].
   //
@@ -387,4 +397,6 @@ namespace std
 //
 #include <libbuild2/name.hxx>
 
+#include <libbuild2/types.ixx>
+
 #endif // LIBBUILD2_TYPES_HXX
diff --git a/libbuild2/types.ixx b/libbuild2/types.ixx
new file mode 100644
index 0000000..5b30cd4
--- /dev/null
+++ b/libbuild2/types.ixx
@@ -0,0 +1,65 @@
+// file      : libbuild2/types.ixx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+namespace build2
+{
+  // Note that in the constructors we cannot pass the file data member to the
+  // base class constructor as it is not initialized yet (and so its base
+  // path/name pointers are not initialized). Thus, we initialize the path
+  // name view in the constructor body.
+  //
+  inline location_value::
+  location_value ()
+  {
+    location::file = file;
+  }
+
+  inline location_value::
+  location_value (const location& l)
+      : location (l.line, l.column), file (l.file)
+  {
+    location::file = file;
+  }
+
+  inline location_value::
+  location_value (location_value&& l)
+      : location (l.line, l.column),
+        file (std::move (l.file))
+  {
+    location::file = file;
+  }
+
+  inline location_value::
+  location_value (const location_value& l)
+      : location (l.line, l.column), file (l.file)
+  {
+    location::file = file;
+  }
+
+  inline location_value& location_value::
+  operator= (location_value&& l)
+  {
+    if (this != &l)
+    {
+      file = std::move (l.file);
+      line = l.line;
+      column = l.column;
+    }
+
+    return *this;
+  }
+
+  inline location_value& location_value::
+  operator= (const location_value& l)
+  {
+    if (this != &l)
+    {
+      file = l.file;
+      line = l.line;
+      column = l.column;
+    }
+
+    return *this;
+  }
+}
diff --git a/libbuild2/utility.cxx b/libbuild2/utility.cxx
index 8e38213..20f0c22 100644
--- a/libbuild2/utility.cxx
+++ b/libbuild2/utility.cxx
@@ -46,11 +46,11 @@ namespace std
   }
 
   ostream&
-  operator<< (ostream& os, const ::butl::path_name& pn)
+  operator<< (ostream& os, const ::butl::path_name_view& v)
   {
-    assert (!pn.empty ());
+    assert (!v.empty ());
 
-    return pn.name ? (os << *pn.name) : (os << *pn.path);
+    return v.name != nullptr && *v.name ? (os << **v.name) : (os << *v.path);
   }
 
   ostream&
diff --git a/libbuild2/version/init.cxx b/libbuild2/version/init.cxx
index c9d5021..9a56756 100644
--- a/libbuild2/version/init.cxx
+++ b/libbuild2/version/init.cxx
@@ -74,8 +74,8 @@ namespace build2
               if (nv.value != pn.string ())
               {
                 path bf (rs.src_path () / rs.root_extra->bootstrap_file);
-                location ml (&f, nv.value_line, nv.value_column);
-                location bl (&bf);
+                location ml (f, nv.value_line, nv.value_column);
+                location bl (bf);
 
                 fail (ml) << "package name " << nv.value << " does not match "
                           << "build system project name " << pn <<
@@ -164,7 +164,7 @@ namespace build2
         }
         catch (const manifest_parsing& e)
         {
-          location l (&f, e.line, e.column);
+          location l (f, e.line, e.column);
           fail (l) << e.description;
         }
         catch (const io_error& e)
diff --git a/libbuild2/version/utility.cxx b/libbuild2/version/utility.cxx
index 0669da7..867aaa8 100644
--- a/libbuild2/version/utility.cxx
+++ b/libbuild2/version/utility.cxx
@@ -63,12 +63,12 @@ namespace build2
         }
         catch (const manifest_parsing& e)
         {
-          location l (&in, e.line, e.column);
+          location l (in, e.line, e.column);
           fail (l) << e.description;
         }
         catch (const manifest_serialization& e)
         {
-          location l (&r.path);
+          location l (r.path);
           fail (l) << e.description;
         }
         catch (const io_error& e)