Squashed 'third_party/elfutils/' content from commit 555e15e

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libdw/dwarf_getsrcfiles.c b/libdw/dwarf_getsrcfiles.c
new file mode 100644
index 0000000..5af6f68
--- /dev/null
+++ b/libdw/dwarf_getsrcfiles.c
@@ -0,0 +1,79 @@
+/* Return source file information of CU.
+   Copyright (C) 2004, 2005, 2013, 2015 Red Hat, Inc.
+   This file is part of elfutils.
+   Written by Ulrich Drepper <drepper@redhat.com>, 2004.
+
+   This file is free software; you can redistribute it and/or modify
+   it under the terms of either
+
+     * the GNU Lesser General Public License as published by the Free
+       Software Foundation; either version 3 of the License, or (at
+       your option) any later version
+
+   or
+
+     * the GNU General Public License as published by the Free
+       Software Foundation; either version 2 of the License, or (at
+       your option) any later version
+
+   or both in parallel, as here.
+
+   elfutils is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received copies of the GNU General Public License and
+   the GNU Lesser General Public License along with this program.  If
+   not, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <assert.h>
+#include <dwarf.h>
+#include "libdwP.h"
+
+
+int
+dwarf_getsrcfiles (Dwarf_Die *cudie, Dwarf_Files **files, size_t *nfiles)
+{
+  if (cudie == NULL)
+    return -1;
+  if (! is_cudie (cudie))
+    {
+      __libdw_seterrno (DWARF_E_NOT_CUDIE);
+      return -1;
+    }
+
+  int res = -1;
+
+  /* Get the information if it is not already known.  */
+  struct Dwarf_CU *const cu = cudie->cu;
+  if (cu->lines == NULL)
+    {
+      Dwarf_Lines *lines;
+      size_t nlines;
+
+      /* Let the more generic function do the work.  It'll create more
+	 data but that will be needed in an real program anyway.  */
+      res = INTUSE(dwarf_getsrclines) (cudie, &lines, &nlines);
+    }
+  else if (cu->files != (void *) -1l)
+    /* We already have the information.  */
+    res = 0;
+
+  if (likely (res == 0))
+    {
+      assert (cu->files != NULL && cu->files != (void *) -1l);
+      *files = cu->files;
+      if (nfiles != NULL)
+	*nfiles = cu->files->nfiles;
+    }
+
+  // XXX Eventually: unlocking here.
+
+  return res;
+}
+INTDEF (dwarf_getsrcfiles)