linux: unexport as many symbols as possible

See discussion on http://code.google.com/p/chromium/issues/detail?id=17557
On linux, exported symbols from a shared library can be overridden by another unit (e.g. the browser) if it exports the same ones. So compile everything with -fvisibility=hidden to make every symbol private by default, and explicitly export the ones that we care about. Also make sure that third-party deps (e.g. icu) don't explicitly export symbols.

Review URL: http://codereview.chromium.org/160317


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21992 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 27 insertions, 12 deletions

diff --git a/o3d/base/icu38_o3d.scons b/o3d/base/icu38_o3d.scons
index 701e511..f7d5a33 100644
--- a/o3d/base/icu38_o3d.scons
+++ b/o3d/base/icu38_o3d.scons
@@ -397,6 +397,14 @@ def MakeObject(env, source, extra_defines):
 
 if CombinedLib:
 
+  if env.Bit('linux'):
+    # U_STATIC_IMPLEMENTATION gets overridden by U_COMBINED_IMPLEMENTATION,
+    # which on linux causes all the symbols to be exported from the shared
+    # library, conflicting with the browser's definition if it uses icu as well
+    # (e.g.  Chrome).
+    combined_flag = []
+  else:
+    combined_flag = ['U_COMBINED_IMPLEMENTATION']
   # These empirically fail to build when U_COMMON_IMPLEMENTATION
   # isn't defined in addition to U_COMBINED_IMPLEMENTATION.  Remove
   # them from the source file list and re-append them with Nodes
@@ -410,13 +418,11 @@ if CombinedLib:
   objects = []
   for n in need_common_implementation:
     common_input_files.remove(n)
-    o = MakeObject(env, n, ['U_COMMON_IMPLEMENTATION',
-                            'U_COMBINED_IMPLEMENTATION'])
+    o = MakeObject(env, n, ['U_COMMON_IMPLEMENTATION'] + combined_flag)
     objects.append(o)
 
   sources = common_input_files + i18n_input_files + stubdata_input_files
-  objects += [MakeObject(env, n, ['U_COMBINED_IMPLEMENTATION'])
-              for n in sources]
+  objects += [MakeObject(env, n, combined_flag) for n in sources]
 
   icu_lib = env.ComponentLibrary('icu', objects);
 
diff --git a/o3d/main.scons b/o3d/main.scons
index d241908..27c52f8 100644
--- a/o3d/main.scons
+++ b/o3d/main.scons
@@ -684,7 +684,7 @@ linux_env.Append(
         ['NACL_LINUX', '1'],
         'SK_BUILD_FOR_UNIX'
     ],
-    CCFLAGS = ['-Wstrict-aliasing', '-m32'],
+    CCFLAGS = ['-Wstrict-aliasing', '-fvisibility=hidden', '-m32'],
     LINKFLAGS = ['-m32'],
     LIBS = ['pthread', 'rt', 'dl'],
     NACL_HTP_LIBS = ['ssl', 'crypto'],
diff --git a/o3d/plugin/cross/main.cc b/o3d/plugin/cross/main.cc
index d6144ca..da16756 100644
--- a/o3d/plugin/cross/main.cc
+++ b/o3d/plugin/cross/main.cc
@@ -148,7 +148,7 @@ namespace o3d {
 extern "C" {
 #endif
 
-NPError OSCALL NP_GetEntryPoints(NPPluginFuncs *pluginFuncs) {
+NPError EXPORT_SYMBOL OSCALL NP_GetEntryPoints(NPPluginFuncs *pluginFuncs) {
   HANDLE_CRASHES;
   pluginFuncs->version = 11;
   pluginFuncs->size = sizeof(*pluginFuncs);
@@ -169,7 +169,7 @@ NPError OSCALL NP_GetEntryPoints(NPPluginFuncs *pluginFuncs) {
   return NPERR_NO_ERROR;
 }
 
-char *NP_GetMIMEDescription(void) {
+char * EXPORT_SYMBOL NP_GetMIMEDescription(void) {
   return O3D_PLUGIN_MIME_TYPE "::O3D MIME";
 }
 
@@ -177,7 +177,8 @@ char *NP_GetMIMEDescription(void) {
 
 #if !defined(O3D_INTERNAL_PLUGIN)
 extern "C" {
-NPError NP_GetValue(void *instance, NPPVariable variable, void *value) {
+NPError EXPORT_SYMBOL NP_GetValue(void *instance, NPPVariable variable,
+                                  void *value) {
   return o3d::NP_GetValue(instance, variable, value);
 }
 }
diff --git a/o3d/plugin/cross/main.h b/o3d/plugin/cross/main.h
index 29e386a..049c688 100644
--- a/o3d/plugin/cross/main.h
+++ b/o3d/plugin/cross/main.h
@@ -59,6 +59,12 @@
 #define HANDLE_CRASHES void(0)
 #else  // O3D_INTERNAL_PLUGIN
 
+#if defined(OS_LINUX)
+#define EXPORT_SYMBOL __attribute__((visibility ("default")))
+#else
+#define EXPORT_SYMBOL
+#endif
+
 extern ExceptionManager *g_exception_manager;
 
 // BreakpadEnabler is a simple class to keep track of whether or not
diff --git a/o3d/plugin/linux/main_linux.cc b/o3d/plugin/linux/main_linux.cc
index 55096db..b91c9d8 100644
--- a/o3d/plugin/linux/main_linux.cc
+++ b/o3d/plugin/linux/main_linux.cc
@@ -622,15 +622,15 @@ namespace o3d {
 extern "C" {
 #endif
 
-NPError OSCALL NP_Initialize(NPNetscapeFuncs *browserFuncs,
-                             NPPluginFuncs *pluginFuncs) {
+NPError EXPORT_SYMBOL OSCALL NP_Initialize(NPNetscapeFuncs *browserFuncs,
+                                           NPPluginFuncs *pluginFuncs) {
   NPError retval = InitializeNPNApi(browserFuncs);
   if (retval != NPERR_NO_ERROR) return retval;
   NP_GetEntryPoints(pluginFuncs);
   return InitializePlugin();
 }
 
-NPError OSCALL NP_Shutdown(void) {
+NPError EXPORT_SYMBOL OSCALL NP_Shutdown(void) {
   HANDLE_CRASHES;
   DLOG(INFO) << "NP_Shutdown";
 
diff --git a/o3d/v8/build.scons b/o3d/v8/build.scons
index 6fd51cc..43e332f 100644
--- a/o3d/v8/build.scons
+++ b/o3d/v8/build.scons
@@ -50,7 +50,7 @@ env = env.Clone(
     V8_MODE = 'release',
     V8_MODE_DIR = '$V8_SRC_DIR/obj/$V8_MODE',
     V8_SCONS_COM = '$PYTHON $SCONS -C $V8_SRC_DIR -f SConstruct '
-                   '$DEBUG_OPTS mode=$V8_MODE importenv=INCLUDE,LIB',
+                   '$DEBUG_OPTS mode=$V8_MODE importenv=INCLUDE,LIB,CCFLAGS',
     SCONS = '$SCONS_DIR/scons.py',
     DEBUG_OPTS = ['--debug=%s' % item for item in GetOption('debug')]
 )
@@ -109,6 +109,8 @@ if v8_env.Bit('windows'):
     v8_env['ENV']['LIB'] =  lib_path  + ";" + v8_env['ENV']['LIB']
   except KeyError:
     v8_env['ENV']['LIB'] = lib_path
+elif v8_env.Bit('linux'):
+  v8_env['ENV']['CCFLAGS'] = '-fvisibility=hidden'
 
 v8_no_snapshot = v8_env.Command(
     v8_scons_targets_no_snapshot,