This patch adds a new third-party library that implements an ELF dynamic linker.

third_party/crazy_linker/crazy_linker/src/crazy_linker_library_list.h

Index: third_party/crazy_linker/crazy_linker/src/crazy_linker_library_list.h
diff --git a/third_party/crazy_linker/crazy_linker/src/crazy_linker_library_list.h b/third_party/crazy_linker/crazy_linker/src/crazy_linker_library_list.h
new file mode 100644
index 0000000000000000000000000000000000000000..ff199ca69eb71a6a3f281dc544896376ba48f127
--- /dev/null
+++ b/third_party/crazy_linker/crazy_linker/src/crazy_linker_library_list.h
@@ -0,0 +1,106 @@
+// Copyright (c) 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.
+
+#ifndef CRAZY_LINKER_LIBRARY_LIST_H
+#define CRAZY_LINKER_LIBRARY_LIST_H
+
+#include <link.h>
+
+#include "crazy_linker_error.h"
+#include "crazy_linker_search_path_list.h"
+#include "elf_traits.h"
+
+// This header contains definitions related to the global list of
+// library views maintained by the crazy linker. Each library view
+// points to either a crazy library, or a system one.
+
+namespace crazy {
+
+class SharedLibrary;
+class LibraryView;
+
+// The list of all shared libraries loaded by the crazy linker.
+// IMPORTANT: This class is not thread-safe!
+class LibraryList {
+ public:
+  LibraryList();
+  ~LibraryList();
+
+  // Find a library in the list by its base name.
+  // |base_name| must not contain a directory separator.
+  LibraryView* FindLibraryByName(const char* base_name);
+
+  // Lookup for a given |symbol_name|, starting from |from_lib|
+  // then through its dependencies in breadth-first search order.
+  // On failure, returns NULL.
+  void* FindSymbolFrom(const char* symbol_name,
+                       LibraryView* from_lib);
+
+  // Return the address of a visible given symbol. Used to implement
+  // the dlsym() wrapper. Returns NULL on failure.
+  void* FindAddressForSymbol(const char* symbol_name);
+
+  // Find a SharedLibrary that contains a given address, or NULL if none
+  // could be found. This simply scans all libraries.
+  LibraryView* FindLibraryForAddress(void* address);
+
+#ifdef __arm__
+  // Find the base address of the .ARM.exidx section corresponding
+  // to the address |pc|, as well as the number of 8-byte entries in
+  // the table into |*count|. Used to implement the wrapper for
+  // dl_unwind_find_exidx().
+  _Unwind_Ptr FindArmExIdx(void* pc, int* count);
+#else
+  typedef int (*PhdrIterationCallback)(dl_phdr_info* info,
+                                       size_t info_size,
+                                       void* data);
+
+  // Loop over all loaded libraries and call the |cb| callback
+  // on each iteration. If the function returns 0, stop immediately
+  // and return its value. Used to implement the wrapper for
+  // dl_iterate_phdr().
+  int IteratePhdr(PhdrIterationCallback callback, void* data);
+#endif
+
+  // Try to load a library, possibly at a fixed address.
+  // On failure, returns NULL and sets the |error| message.
+  LibraryView* LoadLibrary(const char* path,
+                           int dlopen_flags,
+                           uintptr_t load_address,
+                           off_t file_offset,
+                           SearchPathList* search_path_list,
+                           Error* error);
+
+  // Unload a given shared library. This really decrements the library's
+  // internal reference count. When it reaches zero, the library's
+  // destructors are run, its dependencies are unloaded, then the
+  // library is removed from memory.
+  void UnloadLibrary(LibraryView* lib);
+
+  // Used internally by the wrappers only.
+  void AddLibrary(LibraryView* lib);
+
+ private:
+  LibraryList(const LibraryList&);
+  LibraryList& operator=(const LibraryList&);
+
+  void ClearError();
+
+  // The list of all known libraries.
+  Vector<LibraryView*> known_libraries_;
+
+  LibraryView* FindKnownLibrary(const char* name);
+
+  // The list of all libraries loaded by the crazy linker.
+  // This does _not_ include system libraries present in known_libraries_.
+  SharedLibrary* head_;
+
+  size_t count_;
+  bool has_error_;
+  char error_buffer_[512];
+};
+
+}  // namespace crazy
+
+#endif  // CRAZY_LINKER_LIBRARY_LIST_H