Update to Chromium //base at Chromium commit 01cb97b2e09618bbc3a60c7348f0a844eea20547.

android/linker/linker_jni.h

+// Copyright 2015 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.
+
+// This is the Android-specific Chromium linker, a tiny shared library
+// implementing a custom dynamic linker that can be used to load the
+// real Chromium libraries.
+
+// The main point of this linker is to be able to share the RELRO
+// section of libcontentshell.so (or equivalent) between the browser and
+// renderer process.
+
+// This source code *cannot* depend on anything from base/ or the C++
+// STL, to keep the final library small, and avoid ugly dependency issues.
+
+#ifndef BASE_ANDROID_LINKER_LINKER_JNI_H_
+#define BASE_ANDROID_LINKER_LINKER_JNI_H_
+
+#include <android/log.h>
+#include <jni.h>
+#include <stdlib.h>
+
+// Set this to 1 to enable debug traces to the Android log.
+// Note that LOG() from "base/logging.h" cannot be used, since it is
+// in base/ which hasn't been loaded yet.
+#define DEBUG 0
+
+#define TAG "cr.chromium_android_linker"
+
+#if DEBUG
+#define LOG_INFO(FORMAT, ...)                                             \
+  __android_log_print(ANDROID_LOG_INFO, TAG, "%s: " FORMAT, __FUNCTION__, \
+                      ##__VA_ARGS__)
+#else
+#define LOG_INFO(FORMAT, ...) ((void)0)
+#endif
+#define LOG_ERROR(FORMAT, ...)                                             \
+  __android_log_print(ANDROID_LOG_ERROR, TAG, "%s: " FORMAT, __FUNCTION__, \
+                      ##__VA_ARGS__)
+
+#define UNUSED __attribute__((unused))
+
+// See commentary in crazy_linker_elf_loader.cpp for the effect of setting
+// this. If changing there, change here also.
+//
+// For more, see:
+//   https://crbug.com/504410
+#define RESERVE_BREAKPAD_GUARD_REGION 1
+
+namespace chromium_android_linker {
+
+// Larger than the largest library we might attempt to load.
+static const size_t kAddressSpaceReservationSize = 192 * 1024 * 1024;
+
+// Size of any Breakpad guard region. 16MB is comfortably larger than the
+// ~6MB relocation packing of the current 64-bit libchrome.so, the largest we
+// expect to encounter.
+#if RESERVE_BREAKPAD_GUARD_REGION
+static const size_t kBreakpadGuardRegionBytes = 16 * 1024 * 1024;
+#endif
+
+// A simple scoped UTF String class that can be initialized from
+// a Java jstring handle. Modeled like std::string, which cannot
+// be used here.
+class String {
+ public:
+  String(JNIEnv* env, jstring str);
+
+  inline ~String() { ::free(ptr_); }
+
+  inline const char* c_str() const { return ptr_ ? ptr_ : ""; }
+  inline size_t size() const { return size_; }
+
+ private:
+  char* ptr_;
+  size_t size_;
+};
+
+// Return true iff |address| is a valid address for the target CPU.
+inline bool IsValidAddress(jlong address) {
+  return static_cast<jlong>(static_cast<size_t>(address)) == address;
+}
+
+// Find the jclass JNI reference corresponding to a given |class_name|.
+// |env| is the current JNI environment handle.
+// On success, return true and set |*clazz|.
+extern bool InitClassReference(JNIEnv* env,
+                               const char* class_name,
+                               jclass* clazz);
+
+// Initialize a jfieldID corresponding to the field of a given |clazz|,
+// with name |field_name| and signature |field_sig|.
+// |env| is the current JNI environment handle.
+// On success, return true and set |*field_id|.
+extern bool InitFieldId(JNIEnv* env,
+                        jclass clazz,
+                        const char* field_name,
+                        const char* field_sig,
+                        jfieldID* field_id);
+
+// Initialize a jmethodID corresponding to the static method of a given
+// |clazz|, with name |method_name| and signature |method_sig|.
+// |env| is the current JNI environment handle.
+// On success, return true and set |*method_id|.
+extern bool InitStaticMethodId(JNIEnv* env,
+                               jclass clazz,
+                               const char* method_name,
+                               const char* method_sig,
+                               jmethodID* method_id);
+
+// Initialize a jfieldID corresponding to the static field of a given |clazz|,
+// with name |field_name| and signature |field_sig|.
+// |env| is the current JNI environment handle.
+// On success, return true and set |*field_id|.
+extern bool InitStaticFieldId(JNIEnv* env,
+                              jclass clazz,
+                              const char* field_name,
+                              const char* field_sig,
+                              jfieldID* field_id);
+
+// Initialize a jint corresponding to the static integer field of a class
+// with class name |class_name| and field name |field_name|.
+// |env| is the current JNI environment handle.
+// On success, return true and set |*value|.
+extern bool InitStaticInt(JNIEnv* env,
+                          const char* class_name,
+                          const char* field_name,
+                          jint* value);
+
+// Use Android ASLR to create a random library load address.
+// |env| is the current JNI environment handle, and |clazz| a class.
+// Returns the address selected by ASLR.
+extern jlong GetRandomBaseLoadAddress(JNIEnv* env, jclass clazz);
+
+// A class used to model the field IDs of the org.chromium.base.Linker
+// LibInfo inner class, used to communicate data with the Java side
+// of the linker.
+struct LibInfo_class {
+  jfieldID load_address_id;
+  jfieldID load_size_id;
+  jfieldID relro_start_id;
+  jfieldID relro_size_id;
+  jfieldID relro_fd_id;
+
+  // Initialize an instance.
+  bool Init(JNIEnv* env) {
+    jclass clazz;
+    if (!InitClassReference(
+            env, "org/chromium/base/library_loader/Linker$LibInfo", &clazz)) {
+      return false;
+    }
+
+    return InitFieldId(env, clazz, "mLoadAddress", "J", &load_address_id) &&
+           InitFieldId(env, clazz, "mLoadSize", "J", &load_size_id) &&
+           InitFieldId(env, clazz, "mRelroStart", "J", &relro_start_id) &&
+           InitFieldId(env, clazz, "mRelroSize", "J", &relro_size_id) &&
+           InitFieldId(env, clazz, "mRelroFd", "I", &relro_fd_id);
+  }
+
+  void SetLoadInfo(JNIEnv* env,
+                   jobject library_info_obj,
+                   size_t load_address,
+                   size_t load_size) {
+    env->SetLongField(library_info_obj, load_address_id, load_address);
+    env->SetLongField(library_info_obj, load_size_id, load_size);
+  }
+
+  void SetRelroInfo(JNIEnv* env,
+                    jobject library_info_obj,
+                    size_t relro_start,
+                    size_t relro_size,
+                    int relro_fd) {
+    env->SetLongField(library_info_obj, relro_start_id, relro_start);
+    env->SetLongField(library_info_obj, relro_size_id, relro_size);
+    env->SetIntField(library_info_obj, relro_fd_id, relro_fd);
+  }
+
+  // Use this instance to convert a RelroInfo reference into
+  // a crazy_library_info_t.
+  void GetRelroInfo(JNIEnv* env,
+                    jobject library_info_obj,
+                    size_t* relro_start,
+                    size_t* relro_size,
+                    int* relro_fd) {
+    if (relro_start) {
+      *relro_start = static_cast<size_t>(
+          env->GetLongField(library_info_obj, relro_start_id));
+    }
+
+    if (relro_size) {
+      *relro_size = static_cast<size_t>(
+          env->GetLongField(library_info_obj, relro_size_id));
+    }
+
+    if (relro_fd) {
+      *relro_fd = env->GetIntField(library_info_obj, relro_fd_id);
+    }
+  }
+};
+
+// Variable containing LibInfo for the loaded library.
+extern LibInfo_class s_lib_info_fields;
+
+}  // namespace chromium_android_linker
+
+#endif  // BASE_ANDROID_LINKER_LINKER_JNI_H_