Introducing linker namespaces
Bug: http://b/22548808
Change-Id: Ia3af3c0a167f1d16447a3d83bb045d143319b1e1
diff --git a/libc/include/android/dlext.h b/libc/include/android/dlext.h
index 4af5de3..d59de29 100644
--- a/libc/include/android/dlext.h
+++ b/libc/include/android/dlext.h
@@ -98,6 +98,11 @@
*/
ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS = 0x100,
+ /* This flag used to load library in a different namespace. The namespace is
+ * specified in library_namespace.
+ */
+ ANDROID_DLEXT_USE_NAMESPACE = 0x200,
+
/* Mask of valid bits */
ANDROID_DLEXT_VALID_FLAG_BITS = ANDROID_DLEXT_RESERVED_ADDRESS |
ANDROID_DLEXT_RESERVED_ADDRESS_HINT |
@@ -107,9 +112,12 @@
ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET |
ANDROID_DLEXT_FORCE_LOAD |
ANDROID_DLEXT_FORCE_FIXED_VADDR |
- ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS,
+ ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS |
+ ANDROID_DLEXT_USE_NAMESPACE,
};
+struct android_namespace_t;
+
typedef struct {
uint64_t flags;
void* reserved_addr;
@@ -117,10 +125,40 @@
int relro_fd;
int library_fd;
off64_t library_fd_offset;
+ struct android_namespace_t* library_namespace;
} android_dlextinfo;
extern void* android_dlopen_ext(const char* filename, int flag, const android_dlextinfo* extinfo);
+/*
+ * Initializes public namespace. The path is the list of sonames
+ * separated by colon. Example: "libc.so:libm.so:libdl.so".
+ *
+ * The libraries in this list should be loaded prior to this call.
+ */
+extern bool android_init_public_namespace(const char* path);
+
+/*
+ * 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 is_isolated is true the resulted namespace requires all of the libraries
+ * to be on the search path; the search_path is ld_library_path:default_library_path.
+ *
+ * If a library or any of its dependencies are outside of the search path and 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,
+ bool is_isolated);
+
__END_DECLS
#endif /* __ANDROID_DLEXT_H__ */