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

Change-Id: I61cde98949e47e5c8c09c33260de17f30921be79
git-subtree-dir: third_party/elfutils
git-subtree-split: 555e15ebe8bf1eb33d00747173cfc80cc65648a4
diff --git a/libelf/elf_version.c b/libelf/elf_version.c
new file mode 100644
index 0000000..7c336ff
--- /dev/null
+++ b/libelf/elf_version.c
@@ -0,0 +1,69 @@
+/* Coordinate ELF library and application versions.
+   Copyright (C) 1998, 1999, 2000, 2002, 2015 Red Hat, Inc.
+   This file is part of elfutils.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 1998.
+
+   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 <libelfP.h>
+
+
+/* Is the version initialized?  */
+int __libelf_version_initialized;
+
+/* Currently selected version.  */
+unsigned int __libelf_version = EV_CURRENT;
+
+
+unsigned int
+elf_version (unsigned int version)
+{
+  if (version == EV_NONE)
+    return __libelf_version;
+
+  if (likely (version < EV_NUM))
+    {
+      /* Phew, we know this version.  */
+      unsigned int last_version = __libelf_version;
+
+      /* Store the new version.  */
+      __libelf_version = version;
+
+      /* Signal that the version is now initialized.  */
+      __libelf_version_initialized = 1;
+
+      /* And return the last version.  */
+      return last_version;
+    }
+
+  /* We cannot handle this version.  */
+  __libelf_seterrno (ELF_E_UNKNOWN_VERSION);
+  return EV_NONE;
+}
+INTDEF(elf_version)