From 34fa704df45c5f74aeb5230e4bf3930585cf32fb Mon Sep 17 00:00:00 2001
From: Dimitry Ivanov <dimitry@google.com>
Date: Mon, 22 Feb 2016 13:02:35 -0800
Subject: [PATCH 1/2] nativeloader: refactor FindNamespaceByClassLoader method

FindNamespaceByClassLoader returns android_namespace_t* to make
it suitable for exporting this functionality.

Bug: http://b/27189432
Change-Id: Ifef3de753192178e0184fb114596fe956fde2826
---
 libnativeloader/native_loader.cpp | 33 +++++++++++++++----------------
 1 file changed, 16 insertions(+), 17 deletions(-)

diff --git a/libnativeloader/native_loader.cpp b/libnativeloader/native_loader.cpp
index a7a071387..5d35523f2 100644
--- a/libnativeloader/native_loader.cpp
+++ b/libnativeloader/native_loader.cpp
@@ -79,10 +79,10 @@ class LibraryNamespaces {
 
     std::lock_guard<std::mutex> guard(mutex_);
 
-    auto it = FindNamespaceByClassLoader(env, class_loader);
+    android_namespace_t* ns = FindNamespaceByClassLoader(env, class_loader);
 
-    if (it != namespaces_.end()) {
-      return it->second;
+    if (ns != nullptr) {
+      return ns;
     }
 
     uint64_t namespace_type = ANDROID_NAMESPACE_TYPE_ISOLATED;
@@ -90,14 +90,13 @@ class LibraryNamespaces {
       namespace_type |= ANDROID_NAMESPACE_TYPE_SHARED;
     }
 
-    android_namespace_t* ns =
-            android_create_namespace("classloader-namespace",
-                                     nullptr,
-                                     library_path.c_str(),
-                                     namespace_type,
-                                     java_permitted_path != nullptr ?
-                                        permitted_path.c_str() :
-                                        nullptr);
+    ns = android_create_namespace("classloader-namespace",
+                                  nullptr,
+                                  library_path.c_str(),
+                                  namespace_type,
+                                  java_permitted_path != nullptr ?
+                                      permitted_path.c_str() :
+                                      nullptr);
 
     namespaces_.push_back(std::make_pair(env->NewWeakGlobalRef(class_loader), ns));
 
@@ -122,12 +121,12 @@ class LibraryNamespaces {
     return initialized_;
   }
 
-  std::vector<std::pair<jweak, android_namespace_t*>>::const_iterator
-  FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
-    return std::find_if(namespaces_.begin(), namespaces_.end(),
-            [&](const std::pair<jweak, android_namespace_t*>& value) {
-              return env->IsSameObject(value.first, class_loader);
-            });
+  android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
+    auto it = std::find_if(namespaces_.begin(), namespaces_.end(),
+                [&](const std::pair<jweak, android_namespace_t*>& value) {
+                  return env->IsSameObject(value.first, class_loader);
+                });
+    return it != namespaces_.end() ? it->second : nullptr;
   }
 
   bool initialized_;

From 0cd10d83e4e14300d03a60f28547b90d0c805579 Mon Sep 17 00:00:00 2001
From: Dimitry Ivanov <dimitry@google.com>
Date: Mon, 22 Feb 2016 13:48:22 -0800
Subject: [PATCH 2/2] nativeloader: Export FindNamespaceByClassLoader

Bug: http://b/27189432
Change-Id: Ib80dcce949276ee620f601c47b20f783708e8e85
---
 .../include/nativeloader/native_loader.h      | 10 +++++++++
 libnativeloader/native_loader.cpp             | 22 ++++++++++++-------
 2 files changed, 24 insertions(+), 8 deletions(-)

diff --git a/libnativeloader/include/nativeloader/native_loader.h b/libnativeloader/include/nativeloader/native_loader.h
index da072530e..2dec71f1e 100644
--- a/libnativeloader/include/nativeloader/native_loader.h
+++ b/libnativeloader/include/nativeloader/native_loader.h
@@ -19,6 +19,9 @@
 
 #include "jni.h"
 #include <stdint.h>
+#if defined(__ANDROID__)
+#include <android/dlext.h>
+#endif
 
 namespace android {
 
@@ -27,6 +30,13 @@ void* OpenNativeLibrary(JNIEnv* env, int32_t target_sdk_version, const char* pat
                         jobject class_loader, bool is_shared, jstring library_path,
                         jstring permitted_path);
 
+#if defined(__ANDROID__)
+// Look up linker namespace by class_loader. Returns nullptr if
+// there is no namespace associated with the class_loader.
+__attribute__((visibility("default")))
+android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader);
+#endif
+
 };  // namespace android
 
 #endif  // NATIVE_BRIDGE_H_
diff --git a/libnativeloader/native_loader.cpp b/libnativeloader/native_loader.cpp
index 5d35523f2..a64b9720c 100644
--- a/libnativeloader/native_loader.cpp
+++ b/libnativeloader/native_loader.cpp
@@ -103,6 +103,14 @@ class LibraryNamespaces {
     return ns;
   }
 
+  android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
+    auto it = std::find_if(namespaces_.begin(), namespaces_.end(),
+                [&](const std::pair<jweak, android_namespace_t*>& value) {
+                  return env->IsSameObject(value.first, class_loader);
+                });
+    return it != namespaces_.end() ? it->second : nullptr;
+  }
+
  private:
   void PreloadPublicLibraries() {
     // android_init_namespaces() expects all the public libraries
@@ -121,14 +129,6 @@ class LibraryNamespaces {
     return initialized_;
   }
 
-  android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
-    auto it = std::find_if(namespaces_.begin(), namespaces_.end(),
-                [&](const std::pair<jweak, android_namespace_t*>& value) {
-                  return env->IsSameObject(value.first, class_loader);
-                });
-    return it != namespaces_.end() ? it->second : nullptr;
-  }
-
   bool initialized_;
   std::mutex mutex_;
   std::vector<std::pair<jweak, android_namespace_t*>> namespaces_;
@@ -168,4 +168,10 @@ void* OpenNativeLibrary(JNIEnv* env, int32_t target_sdk_version, const char* pat
 #endif
 }
 
+#if defined(__ANDROID__)
+android_namespace_t* FindNamespaceByClassLoader(JNIEnv* env, jobject class_loader) {
+  return g_namespaces->FindNamespaceByClassLoader(env, class_loader);
+}
+#endif
+
 }; //  android namespace