Remove function level static initializers media library initialization.

Moves media library initialization into a lazy initializer and dedups a
bunch of code.  This will also be the eventual home for global media
initialization routines (YUV and VectorMath).

BUG=224662
TEST=compiles, media library works.

Review URL: https://chromiumcodereview.appspot.com/14891002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198559 0039d316-1c4b-4281-b951-d872f2087c98

7 files changed, 110 insertions, 104 deletions

diff --git a/media/base/media.cc b/media/base/media.cc
new file mode 100644
index 0000000..f70d7ca
--- /dev/null
+++ b/media/base/media.cc
@@ -0,0 +1,74 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/base/media.h"
+
+#include "base/files/file_path.h"
+#include "base/lazy_instance.h"
+#include "base/path_service.h"
+#include "base/synchronization/lock.h"
+#include "build/build_config.h"
+
+namespace media {
+
+namespace internal {
+// Platform specific initialization method.
+extern bool InitializeMediaLibraryInternal(const base::FilePath& module_dir);
+}  // namespace internal
+
+// Media must only be initialized once, so use a LazyInstance to ensure this.
+class MediaInitializer {
+ public:
+  bool Initialize(const base::FilePath& module_dir) {
+    base::AutoLock auto_lock(lock_);
+    if (!tried_initialize_) {
+      tried_initialize_ = true;
+      initialized_ = internal::InitializeMediaLibraryInternal(module_dir);
+    }
+    return initialized_;
+  }
+
+  bool IsInitialized() {
+    base::AutoLock auto_lock(lock_);
+    return initialized_;
+  }
+
+ private:
+  friend struct base::DefaultLazyInstanceTraits<MediaInitializer>;
+
+  MediaInitializer()
+      : initialized_(false),
+        tried_initialize_(false) {
+    // TODO(dalecurtis): Add initialization of YUV and VectorMath libraries.
+  }
+
+  ~MediaInitializer() {
+    NOTREACHED() << "MediaInitializer should be leaky!";
+  }
+
+  base::Lock lock_;
+  bool initialized_;
+  bool tried_initialize_;
+
+  DISALLOW_COPY_AND_ASSIGN(MediaInitializer);
+};
+
+static base::LazyInstance<MediaInitializer>::Leaky g_media_library =
+    LAZY_INSTANCE_INITIALIZER;
+
+bool InitializeMediaLibrary(const base::FilePath& module_dir) {
+  return g_media_library.Get().Initialize(module_dir);
+}
+
+void InitializeMediaLibraryForTesting() {
+  base::FilePath module_dir;
+  CHECK(PathService::Get(base::DIR_EXE, &module_dir));
+  CHECK(g_media_library.Get().Initialize(module_dir));
+}
+
+bool IsMediaLibraryInitialized() {
+  return g_media_library.Get().IsInitialized();
+}
+
+}  // namespace media
diff --git a/media/base/media.h b/media/base/media.h
index 5518961..0eeb092 100644
--- a/media/base/media.h
+++ b/media/base/media.h
@@ -18,7 +18,7 @@ namespace media {
 
 // Attempts to initialize the media library (loading DLLs, DSOs, etc.).
 //
-// If |module_dir| is the emptry string, then the system default library paths
+// If |module_dir| is the empty string, then the system default library paths
 // are searched for the dynamic libraries.  If a |module_dir| is provided, then
 // only the specified |module_dir| will be searched for the dynamic libraries.
 //
diff --git a/media/base/media_android.cc b/media/base/media_android.cc
index 8008d48..090e73a 100644
--- a/media/base/media_android.cc
+++ b/media/base/media_android.cc
@@ -6,31 +6,16 @@
 
 #include <cpu-features.h>
 
-#include "base/android/jni_android.h"
-#include "base/logging.h"
-#include "media/base/android/media_jni_registrar.h"
+#include "base/files/file_path.h"
 
 namespace media {
+namespace internal {
 
-// Caches the result of the check for NEON support.
-static bool g_media_library_is_initialized = false;
-
-bool InitializeMediaLibrary(const base::FilePath& module_dir) {
+bool InitializeMediaLibraryInternal(const base::FilePath& module_dir) {
   // No real initialization is necessary but we do need to check if
   // Neon is supported because the FFT library requires Neon.
-  g_media_library_is_initialized = (android_getCpuFeatures() &
-                                    ANDROID_CPU_ARM_FEATURE_NEON) != 0;
-  return g_media_library_is_initialized;
-}
-
-void InitializeMediaLibraryForTesting() {
-  // Register JNI bindings for android.
-  JNIEnv* env = base::android::AttachCurrentThread();
-  RegisterJni(env);
-}
-
-bool IsMediaLibraryInitialized() {
-  return g_media_library_is_initialized;
+  return (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
 }
 
+}  // namespace internal
 }  // namespace media
diff --git a/media/base/media_posix.cc b/media/base/media_posix.cc
index 01d9e5f..243495a 100644
--- a/media/base/media_posix.cc
+++ b/media/base/media_posix.cc
@@ -22,6 +22,7 @@ using third_party_ffmpeg::StubPathMap;
 #endif  // !defined(USE_SYSTEM_FFMPEG)
 
 namespace media {
+namespace internal {
 
 // Handy to prevent shooting ourselves in the foot with macro wizardry.
 #if !defined(LIBAVCODEC_VERSION_MAJOR) || \
@@ -47,18 +48,11 @@ static const base::FilePath::CharType kSumoLib[] =
 #error "Do not know how to construct DSO name for this OS."
 #endif
 
-// Use a global to indicate whether the library has been initialized or not.  We
-// rely on function level static initialization in InitializeMediaLibrary() to
-// guarantee this is only set once in a thread safe manner.
-static bool g_media_library_is_initialized = false;
-
-static bool InitializeMediaLibraryInternal(const base::FilePath& module_dir) {
-  DCHECK(!g_media_library_is_initialized);
-
+bool InitializeMediaLibraryInternal(const base::FilePath& module_dir) {
 #if defined(USE_SYSTEM_FFMPEG)
   // No initialization is necessary when using system ffmpeg,
   // we just link directly with system ffmpeg libraries.
-  g_media_library_is_initialized = true;
+  return true;
 #else
   StubPathMap paths;
 
@@ -74,26 +68,9 @@ static bool InitializeMediaLibraryInternal(const base::FilePath& module_dir) {
   paths[kModuleFfmpegsumo].push_back(module_dir.Append(
       FILE_PATH_LITERAL(DSO_NAME("avformat", AVFORMAT_VERSION))).value());
 
-  g_media_library_is_initialized = InitializeStubs(paths);
+  return InitializeStubs(paths);
 #endif  // !defined(USE_SYSTEM_FFMPEG)
-  return g_media_library_is_initialized;
-}
-
-bool InitializeMediaLibrary(const base::FilePath& base_path) {
-  static const bool kMediaLibraryInitialized =
-      InitializeMediaLibraryInternal(base_path);
-  DCHECK_EQ(kMediaLibraryInitialized, g_media_library_is_initialized);
-  return kMediaLibraryInitialized;
-}
-
-void InitializeMediaLibraryForTesting() {
-  base::FilePath file_path;
-  CHECK(PathService::Get(base::DIR_EXE, &file_path));
-  CHECK(InitializeMediaLibrary(file_path));
-}
-
-bool IsMediaLibraryInitialized() {
-  return g_media_library_is_initialized;
 }
 
+}  // namespace internal
 }  // namespace media
diff --git a/media/base/media_stub.cc b/media/base/media_stub.cc
index aadfbd1..9efb37e 100644
--- a/media/base/media_stub.cc
+++ b/media/base/media_stub.cc
@@ -4,31 +4,16 @@
 
 #include "media/base/media.h"
 
-#include "base/logging.h"
-
-#if defined(OS_ANDROID)
-#include "base/android/jni_android.h"
-#include "media/base/android/media_jni_registrar.h"
-#endif
+#include "base/files/file_path.h"
 
 // This file is intended for platforms that don't need to load any media
-// libraries (e.g., Android and iOS).
+// libraries (e.g., iOS).
 namespace media {
+namespace internal {
 
-bool InitializeMediaLibrary(const base::FilePath& module_dir) {
-  return true;
-}
-
-void InitializeMediaLibraryForTesting() {
-#if defined(OS_ANDROID)
-  // Register JNI bindings for android.
-  JNIEnv* env = base::android::AttachCurrentThread();
-  RegisterJni(env);
-#endif
-}
-
-bool IsMediaLibraryInitialized() {
+bool InitializeMediaLibraryInternal(const base::FilePath& module_dir) {
   return true;
 }
 
+}  // namespace internal
 }  // namespace media
diff --git a/media/base/media_win.cc b/media/base/media_win.cc
index b6602f9..43bf6a7 100644
--- a/media/base/media_win.cc
+++ b/media/base/media_win.cc
@@ -12,56 +12,28 @@
 #include <delayimp.h>
 
 #include "base/files/file_path.h"
-#include "base/logging.h"
-#include "base/native_library.h"
-#include "base/path_service.h"
 
 #pragma comment(lib, "delayimp.lib")
 
 namespace media {
+namespace internal {
 
-// FFmpeg library name.
-static const char kFFmpegDLL[] = "ffmpegsumo.dll";
-
-// Use a global to indicate whether the library has been initialized or not.  We
-// rely on function level static initialization in InitializeMediaLibrary() to
-// guarantee this is only set once in a thread safe manner.
-static bool g_media_library_is_initialized = false;
-
-static bool InitializeMediaLibraryInternal(const base::FilePath& base_path) {
-  DCHECK(!g_media_library_is_initialized);
-
+bool InitializeMediaLibraryInternal(const base::FilePath& module_dir) {
   // LoadLibraryEx(..., LOAD_WITH_ALTERED_SEARCH_PATH) cannot handle
   // relative path.
-  if (!base_path.IsAbsolute())
+  if (!module_dir.IsAbsolute())
     return false;
 
   // Use alternate DLL search path so we don't load dependencies from the
   // system path.  Refer to http://crbug.com/35857
+  static const char kFFmpegDLL[] = "ffmpegsumo.dll";
   HMODULE lib = ::LoadLibraryEx(
-      base_path.AppendASCII(kFFmpegDLL).value().c_str(), NULL,
+      module_dir.AppendASCII(kFFmpegDLL).value().c_str(), NULL,
       LOAD_WITH_ALTERED_SEARCH_PATH);
 
   // Check that we loaded the library successfully.
-  g_media_library_is_initialized = (lib != NULL);
-  return g_media_library_is_initialized;
-}
-
-bool InitializeMediaLibrary(const base::FilePath& base_path) {
-  static const bool kMediaLibraryInitialized =
-      InitializeMediaLibraryInternal(base_path);
-  DCHECK_EQ(kMediaLibraryInitialized, g_media_library_is_initialized);
-  return kMediaLibraryInitialized;
-}
-
-void InitializeMediaLibraryForTesting() {
-  base::FilePath file_path;
-  CHECK(PathService::Get(base::DIR_EXE, &file_path));
-  CHECK(InitializeMediaLibrary(file_path));
-}
-
-bool IsMediaLibraryInitialized() {
-  return g_media_library_is_initialized;
+  return lib != NULL;
 }
 
+}  // namespace internal
 }  // namespace media
diff --git a/media/base/run_all_unittests.cc b/media/base/run_all_unittests.cc
index c413874..899172b 100644
--- a/media/base/run_all_unittests.cc
+++ b/media/base/run_all_unittests.cc
@@ -4,9 +4,15 @@
 
 #include "base/command_line.h"
 #include "base/test/test_suite.h"
+#include "build/build_config.h"
 #include "media/base/media.h"
 #include "media/base/media_switches.h"
 
+#if defined(OS_ANDROID)
+#include "base/android/jni_android.h"
+#include "media/base/android/media_jni_registrar.h"
+#endif
+
 class TestSuiteNoAtExit : public base::TestSuite {
  public:
   TestSuiteNoAtExit(int argc, char** argv) : TestSuite(argc, argv) {}
@@ -18,6 +24,13 @@ class TestSuiteNoAtExit : public base::TestSuite {
 void TestSuiteNoAtExit::Initialize() {
   // Run TestSuite::Initialize first so that logging is initialized.
   base::TestSuite::Initialize();
+
+#if defined(OS_ANDROID)
+  // Register JNI bindings for android.
+  JNIEnv* env = base::android::AttachCurrentThread();
+  media::RegisterJni(env);
+#endif
+
   // Run this here instead of main() to ensure an AtExitManager is already
   // present.
   media::InitializeMediaLibraryForTesting();