Android: Add chrome-specific dynamic linker.

content/public/android/java/src/org/chromium/content/app/LinkerParams.java

+// Copyright 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.
+
+package org.chromium.content.app;
+
+import android.content.Intent;
+
+/**
+ * A class to hold information passed from the browser process to each
+ * service one when using the Chrome linker. For more information, read the
+ * technical notes in Linker.java.
+ */
+public class LinkerParams {
+    // Use this base address to load native shared libraries. If 0, ignore other members.
+    public final long mBaseLoadAddress;
+
+    // If true, wait for a shared RELRO Bundle just after loading the libraries.
+    public final boolean mWaitForSharedRelro;
+
+    // If not empty, name of Linker.TestRunner implementation that needs to be
+    // registered in the service process.
+    public final String mTestRunnerClassName;
+
+    public LinkerParams(long baseLoadAddress,
+                        boolean waitForSharedRelro,
+                        String testRunnerClassName) {
+        mBaseLoadAddress = baseLoadAddress;
+        mWaitForSharedRelro = waitForSharedRelro;
+        mTestRunnerClassName = testRunnerClassName;
+    }
+
+    private static final String EXTRA_LINKER_PARAMS_BASE_LOAD_ADDRESS =
+        "org.chromium.content.common.linker_params.base_load_address";
+
+    private static final String EXTRA_LINKER_PARAMS_WAIT_FOR_SHARED_RELRO =
+        "org.chromium.content.common.linker_params.wait_for_shared_relro";
+
+    private static final String EXTRA_LINKER_PARAMS_TEST_RUNNER_CLASS_NAME =
+        "org.chromium.content.common.linker_params.test_runner_class_name";
+
+    /**
+     * Ensure this LinkerParams instance is sent to a service process by adding
+     * it to an intent's extras.
+     * @param intent An Intent use to start or connect to the child service process.
+     */
+    public void addIntentExtras(Intent intent) {
+        intent.putExtra(EXTRA_LINKER_PARAMS_BASE_LOAD_ADDRESS, mBaseLoadAddress);
+        intent.putExtra(EXTRA_LINKER_PARAMS_WAIT_FOR_SHARED_RELRO, mWaitForSharedRelro);
+        intent.putExtra(EXTRA_LINKER_PARAMS_TEST_RUNNER_CLASS_NAME, mTestRunnerClassName);
+    }
+
+    /**
+     * Use this constructor to recreate a LinkerParams instance from an Intent.
+     * @param intent An Intent, its content must have been populated by a previous
+     * call to addIntentExtras().
+     */
+    public LinkerParams(Intent intent) {
+        mBaseLoadAddress = intent.getLongExtra(EXTRA_LINKER_PARAMS_BASE_LOAD_ADDRESS, 0);
+        mWaitForSharedRelro = intent.getBooleanExtra(
+                EXTRA_LINKER_PARAMS_WAIT_FOR_SHARED_RELRO, false);
+        mTestRunnerClassName = intent.getStringExtra(
+                EXTRA_LINKER_PARAMS_TEST_RUNNER_CLASS_NAME);
+    }
+
+    // For debugging traces only.
+    public String toString() {
+        return String.format(
+                "LinkerParams(baseLoadAddress:0x%x, waitForSharedRelro:%s, " +
+                        "testRunnerClassName:%s",
+                mBaseLoadAddress,
+                mWaitForSharedRelro ? "true" : "false",
+                mTestRunnerClassName);
+    }
+}