libpolicy: only export symbols we want to

Only the policy namespace is exported in the policy headers, so make
sure we hide all other symbols.  Otherwise we end up exporting symbols
that we imported from libbase.

BUG=chromium-os:26654
TEST=`emerge-x86-alex libchromeos update_manager metrics` still works
TEST=`libpolicy_unittest` passes
TEST=`cbuildbot arm-generic-full` passes

Change-Id: I9023e9adb9846f9da6c7a04fddd0d60212d18fc0
Reviewed-on: https://gerrit.chromium.org/gerrit/16288
Reviewed-by: Julian Pastarmov <pastarmovj@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Ready: Mike Frysinger <vapier@chromium.org>

2 files changed, 20 insertions, 1 deletions

diff --git a/SConstruct b/SConstruct
index ee96e61..a9fdefd 100644
--- a/SConstruct
+++ b/SConstruct
@@ -171,7 +171,8 @@ env.Append(
     LIBS = [libchromeos, 'protobuf-lite', 'pthread', 'rt'],
     LIBPATH = ['.', '../third_party/chrome'],
     LINKFLAGS = ['-Wl,--as-needed', '-Wl,-z,defs',
-                 '-Wl,-soname,lib%s.so' % libpolicy],
+                 '-Wl,-soname,lib%s.so' % libpolicy,
+                 '-Wl,--version-script,libpolicy.ver'],
   )
 
 # Build the protobuf definitions.
diff --git a/libpolicy.ver b/libpolicy.ver
new file mode 100644
index 0000000..8c01cdf
--- /dev/null
+++ b/libpolicy.ver
@@ -0,0 +1,18 @@
+# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  global:
+    extern "C++" {
+      enterprise_management::*;
+      typeinfo*for*enterprise_management::*;
+      vtable*for*enterprise_management*;
+
+      policy::*;
+      typeinfo*for*policy::*;
+      vtable*for*policy*;
+    };
+
+  local: *;
+};