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

third_party/crazy_linker/crazy_linker/tests/test_load_library_depends.cpp

+// 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.
+
+// A crazy linker test to:
+// - Load a library (libbar.so) with the linker, which depends on
+//   another library (libfoo.so)
+// - Find the address of the "Bar" function in libbar.so.
+// - Call the Bar() function, which ends up calling Foo() in libfoo.so
+// - Close the library.
+
+#include <crazy_linker.h>
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef void (*FunctionPtr)();
+
+static void Panic(const char* fmt, ...) {
+  va_list args;
+  fprintf(stderr, "PANIC: ");
+  va_start(args, fmt);
+  vfprintf(stderr, fmt, args);
+  va_end(args);
+  exit(1);
+}
+
+int main() {
+  crazy_context_t* context = crazy_context_create();
+  crazy_library_t* library;
+
+  // DEBUG
+  crazy_context_set_load_address(context, 0x20000000);
+
+  // Load libbar.so
+  if (!crazy_library_open(&library,
+                          "libbar.so",
+                          context)) {
+    Panic("Could not open library: %s\n", crazy_context_get_error(context));
+  }
+
+  // Find the "Bar" symbol.
+  FunctionPtr bar_func;
+  if (!crazy_library_find_symbol(library,
+                                 "Bar",
+                                 reinterpret_cast<void**>(&bar_func))) {
+    Panic("Could not find 'Bar' in libbar.so\n");
+  }
+
+  // Call it.
+  (*bar_func)();
+
+  // Find the "Foo" symbol from libbar.so
+  FunctionPtr foo_func;
+  if (!crazy_library_find_symbol(library,
+                                 "Foo",
+                                 reinterpret_cast<void**>(&foo_func))) {
+    Panic("Could not find 'Foo' from libbar.so\n");
+  }
+
+  // Close the library.
+  printf("Closing libbar.so\n");
+  crazy_library_close(library);
+
+  crazy_context_destroy(context);
+
+  return 0;
+}