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diff --git a/libnativeloader/include/nativeloader/dlext_namespaces.h b/libnativeloader/include/nativeloader/dlext_namespaces.h
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index 0000000000..8937636cf5
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+++ b/libnativeloader/include/nativeloader/dlext_namespaces.h
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __ANDROID_DLEXT_NAMESPACES_H__
+#define __ANDROID_DLEXT_NAMESPACES_H__
+
+#include <android/dlext.h>
+#include <stdbool.h>
+
+__BEGIN_DECLS
+
+enum {
+  /* A regular namespace is the namespace with a custom search path that does
+   * not impose any restrictions on the location of native libraries.
+   */
+  ANDROID_NAMESPACE_TYPE_REGULAR = 0,
+
+  /* An isolated namespace requires all the libraries to be on the search path
+   * or under permitted_when_isolated_path. The search path is the union of
+   * ld_library_path and default_library_path.
+   */
+  ANDROID_NAMESPACE_TYPE_ISOLATED = 1,
+
+  /* The shared namespace clones the list of libraries of the caller namespace upon creation
+   * which means that they are shared between namespaces - the caller namespace and the new one
+   * will use the same copy of a library if it was loaded prior to android_create_namespace call.
+   *
+   * Note that libraries loaded after the namespace is created will not be shared.
+   *
+   * Shared namespaces can be isolated or regular. Note that they do not inherit the search path nor
+   * permitted_path from the caller's namespace.
+   */
+  ANDROID_NAMESPACE_TYPE_SHARED = 2,
+
+  /* This flag instructs linker to enable grey-list workaround for the namespace.
+   * See http://b/26394120 for details.
+   */
+  ANDROID_NAMESPACE_TYPE_GREYLIST_ENABLED = 0x08000000,
+
+  /* This flag instructs linker to use this namespace as the anonymous
+   * namespace. The anonymous namespace is used in the case when linker cannot
+   * identify the caller of dlopen/dlsym. This happens for the code not loaded
+   * by dynamic linker; for example calls from the mono-compiled code. There can
+   * be only one anonymous namespace in a process. If there already is an
+   * anonymous namespace in the process, using this flag when creating a new
+   * namespace causes an error.
+   */
+  ANDROID_NAMESPACE_TYPE_ALSO_USED_AS_ANONYMOUS = 0x10000000,
+
+  ANDROID_NAMESPACE_TYPE_SHARED_ISOLATED =
+      ANDROID_NAMESPACE_TYPE_SHARED | ANDROID_NAMESPACE_TYPE_ISOLATED,
+};
+
+/*
+ * Creates new linker namespace.
+ * ld_library_path and default_library_path represent the search path
+ * for the libraries in the namespace.
+ *
+ * The libraries in the namespace are searched by folowing order:
+ * 1. ld_library_path (Think of this as namespace-local LD_LIBRARY_PATH)
+ * 2. In directories specified by DT_RUNPATH of the "needed by" binary.
+ * 3. deault_library_path (This of this as namespace-local default library path)
+ *
+ * When type is ANDROID_NAMESPACE_TYPE_ISOLATED the resulting namespace requires all of
+ * the libraries to be on the search path or under the permitted_when_isolated_path;
+ * the search_path is ld_library_path:default_library_path. Note that the
+ * permitted_when_isolated_path path is not part of the search_path and
+ * does not affect the search order. It is a way to allow loading libraries from specific
+ * locations when using absolute path.
+ * If a library or any of its dependencies are outside of the permitted_when_isolated_path
+ * and search_path, and it is not part of the public namespace dlopen will fail.
+ */
+extern struct android_namespace_t* android_create_namespace(
+    const char* name, const char* ld_library_path, const char* default_library_path, uint64_t type,
+    const char* permitted_when_isolated_path, struct android_namespace_t* parent);
+
+/*
+ * Creates a link between namespaces. Every link has list of sonames of
+ * shared libraries. These are the libraries which are accessible from
+ * namespace 'from' but loaded within namespace 'to' context.
+ * When to namespace is nullptr this function establishes a link between
+ * 'from' namespace and the default namespace.
+ *
+ * The lookup order of the libraries in namespaces with links is following:
+ * 1. Look inside current namespace using 'this' namespace search path.
+ * 2. Look in linked namespaces
+ * 2.1. Perform soname check - if library soname is not in the list of shared
+ *      libraries sonames skip this link, otherwise
+ * 2.2. Search library using linked namespace search path. Note that this
+ *      step will not go deeper into linked namespaces for this library but
+ *      will do so for DT_NEEDED libraries.
+ */
+extern bool android_link_namespaces(struct android_namespace_t* from,
+                                    struct android_namespace_t* to,
+                                    const char* shared_libs_sonames);
+
+extern struct android_namespace_t* android_get_exported_namespace(const char* name);
+
+__END_DECLS
+
+#endif /* __ANDROID_DLEXT_NAMESPACES_H__ */