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Diffstat (limited to 'sysdeps/unix/sysv/linux/dl-vdso.c')
-rw-r--r--sysdeps/unix/sysv/linux/dl-vdso.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/dl-vdso.c b/sysdeps/unix/sysv/linux/dl-vdso.c
new file mode 100644
index 0000000000..e1be097734
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/dl-vdso.c
@@ -0,0 +1,59 @@
+/* ELF symbol resolve functions for VDSO objects.
+   Copyright (C) 2005 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "config.h"
+#include <dl-hash.h>
+#include <ldsodefs.h>
+
+
+void *
+internal_function
+_dl_vdso_vsym (const char *name, const char *version)
+{
+  struct link_map *map = GLRO (dl_sysinfo_map);
+  void *value = NULL;
+
+
+  if (map != NULL)
+    {
+      /* Use a WEAK REF so we don't error out if the symbol is not found.  */
+      ElfW (Sym) wsym;
+      memset (&wsym, 0, sizeof (ElfW (Sym)));
+      wsym.st_info = (unsigned char) ELFW (ST_INFO (STB_WEAK, STT_NOTYPE));
+
+      /* Compute hash value to the version string.  */
+      struct r_found_version vers;
+      vers.name = version;
+      vers.hidden = 1;
+      vers.hash = _dl_elf_hash (version);
+      /* We don't have a specific file where the symbol can be found.  */
+      vers.filename = NULL;
+
+      /* Search the scope of the vdso map.  */
+      const ElfW (Sym) *ref = &wsym;
+      lookup_t result = GLRO (dl_lookup_symbol_x) (name, map, &ref,
+						   map->l_local_scope,
+						   &vers, 0, 0, NULL);
+
+      if (ref != NULL)
+	value = DL_SYMBOL_ADDRESS (result, ref);
+    }
+
+  return value;
+}