Initial modularization with both Clang and VC hacks

Note: gave up on VC about half way though.

1 files changed, 164 insertions, 0 deletions

diff --git a/libbutl/path-map.mxx b/libbutl/path-map.mxx
new file mode 100644
index 0000000..c526a89
--- /dev/null
+++ b/libbutl/path-map.mxx
@@ -0,0 +1,164 @@
+// file      : libbutl/path-map.mxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef __cpp_modules
+#pragma once
+#endif
+
+// C includes.
+
+#ifndef __cpp_lib_modules
+#include <algorithm> // min()
+#endif
+
+// Other includes.
+
+#ifdef __cpp_modules
+export module butl.path_map;
+#ifdef __cpp_lib_modules
+import std.core;
+#endif
+import butl.path;
+import butl.prefix_map;
+#else
+#include <libbutl/path.mxx>
+#include <libbutl/prefix-map.mxx>
+#endif
+
+#include <libbutl/export.hxx>
+
+LIBBUTL_MODEXPORT namespace butl
+{
+  // prefix_map for filesystem paths
+  //
+  // Important: the paths should be normalized but can use different directory
+  // separators and different case on case-insensitive platforms.
+  //
+  // Note that the path's representation of POSIX root ('/') is inconsistent
+  // in that we have a trailing delimiter at the end of the path (its "proper"
+  // representation would have been an empty string but that would have
+  // clashed with empty paths). To work around this snag, this implementation,
+  // during key comparison, detects '/' and treats it as empty. Note that the
+  // map will still store the key as you have first inserted it. So if you
+  // want a particular representation (i.e., empty or '/'), pre- populate the
+  // map with it.
+  //
+  template <typename C, typename K>
+  struct compare_prefix<basic_path<C, K>>
+  {
+    typedef basic_path<C, K> key_type;
+
+    typedef C delimiter_type;
+    typedef typename key_type::string_type string_type;
+    typedef typename key_type::size_type size_type;
+    typedef typename key_type::traits traits_type;
+
+    explicit
+    compare_prefix (delimiter_type) {}
+
+    bool
+    operator() (const key_type& x, const key_type& y) const
+    {
+      const string_type& xs (x.string ());
+      const string_type& ys (y.string ());
+
+      return compare (xs.c_str (),
+                      root (xs) ? 0 : xs.size (),
+                      ys.c_str (),
+                      root (ys) ? 0 : ys.size ()) < 0;
+    }
+
+    bool
+    prefix (const key_type& p, const key_type& k) const
+    {
+      const string_type& ps (p.string ());
+      const string_type& ks (k.string ());
+
+      return prefix (root (ps) ? string_type () : ps,
+                     root (ks) ? string_type () : ks);
+    }
+
+  protected:
+    bool
+    prefix (const string_type& p, const string_type& k) const
+    {
+      // The same code as in prefix_map but using our compare().
+      //
+      size_type pn (p.size ()), kn (k.size ());
+      return pn == 0 || // Empty key is always a prefix.
+        (pn <= kn &&
+         compare (p.c_str (), pn, k.c_str (), pn == kn ? pn : pn + 1) == 0);
+    }
+
+    int
+    compare (const C* x, size_type xn,
+             const C* y, size_type yn) const
+    {
+      size_type n (std::min (xn, yn));
+      int r (traits_type::compare (x, n, y, n));
+
+      if (r == 0)
+      {
+        // Pretend there is a delimiter characters at the end of the
+        // shorter string.
+        //
+        char xc (xn > n ? x[n] : (xn++, traits_type::directory_separator));
+        char yc (yn > n ? y[n] : (yn++, traits_type::directory_separator));
+        r = traits_type::compare (&xc, 1, &yc, 1);
+
+        // If we are still equal, then compare the lengths.
+        //
+        if (r == 0)
+          r = (xn == yn ? 0 : (xn < yn ? -1 : 1));
+      }
+
+      return r;
+    }
+
+    static bool
+    root (const string_type& p)
+    {
+      return p.size () == 1 && key_type::traits::is_separator (p[0]);
+    }
+  };
+
+  // Note that the delimiter character is not used (is_delimiter() from
+  // path_traits is used instead).
+  //
+  template <typename P, typename T>
+  struct path_map_impl: prefix_map<P, T, P::traits::directory_separator>
+  {
+    using base = prefix_map<P, T, P::traits::directory_separator>;
+    using base::base;
+
+    using iterator = typename base::iterator;
+    using const_iterator = typename base::const_iterator;
+
+    // Find the most qualified entry that is a superpath of this path.
+    //
+    iterator
+    find_sup (const P& p)
+    {
+      // Get the greatest less than, if any. We might still not be a sub. Note
+      // also that we still have to check the last element if upper_bound()
+      // returned end().
+      //
+      auto i (this->upper_bound (p));
+      return i == this->begin () || !p.sub ((--i)->first) ? this->end () : i;
+    }
+
+    const_iterator
+    find_sup (const P& p) const
+    {
+      auto i (this->upper_bound (p));
+      return i == this->begin () || !p.sub ((--i)->first) ? this->end () : i;
+    }
+  };
+
+  template <typename T>
+  using path_map = path_map_impl<path, T>;
+
+  template <typename T>
+  using dir_path_map = path_map_impl<dir_path, T>;
+}