Prepend pattern search paths to PATH when running binutils

This way any dependent tools (such as mt.exe that is invoked by link.exe)
are first search for in there.

1 files changed, 47 insertions, 0 deletions

diff --git a/libbuild2/bin/utility.hxx b/libbuild2/bin/utility.hxx
new file mode 100644
index 0000000..cc2b727
--- /dev/null
+++ b/libbuild2/bin/utility.hxx
@@ -0,0 +1,47 @@
+// file      : libbuild2/bin/utility.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2019 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef LIBBUILD2_BIN_UTILITY_HXX
+#define LIBBUILD2_BIN_UTILITY_HXX
+
+#include <libbuild2/types.hxx>
+#include <libbuild2/utility.hxx>
+
+#include <libbuild2/scope.hxx>
+#include <libbuild2/variable.hxx>
+
+namespace build2
+{
+  namespace bin
+  {
+    // Lookup the bin.pattern value and split it into the pattern and the
+    // search paths.
+    //
+    struct pattern_paths
+    {
+      const char* pattern = nullptr;
+      const char* paths   = nullptr;
+    };
+
+    inline pattern_paths
+    lookup_pattern (const scope& rs)
+    {
+      pattern_paths r;
+
+      // Theoretically, we could have both the pattern and the search paths,
+      // for example, the pattern can come first followed by the paths.
+      //
+      if (const string* v = cast_null<string> (rs["bin.pattern"]))
+      {
+        (path::traits_type::is_separator (v->back ())
+         ? r.paths
+         : r.pattern) = v->c_str ();
+      }
+
+      return r;
+    }
+  }
+}
+
+#endif // LIBBUILD2_BIN_UTILITY_HXX