base/android/library_loader/library_loader_hooks.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "base/android/library_loader/library_loader_hooks.h"
   6
   7 #include "base/android/command_line_android.h"
   8 #include "base/android/jni_string.h"
   9 #include "base/android/library_loader/library_load_from_apk_status_codes.h"
  10 #include "base/android/library_loader/library_prefetcher.h"
  11 #include "base/at_exit.h"
  12 #include "base/metrics/histogram.h"
  13 #include "jni/LibraryLoader_jni.h"
  14
  15 namespace base {
  16 namespace android {
  17
  18 namespace {
  19
  20 base::AtExitManager* g_at_exit_manager = NULL;
  21 const char* g_library_version_number = "";
  22 LibraryLoadedHook* g_registration_callback = NULL;
  23
  24 enum RendererHistogramCode {
  25   // Renderer load at fixed address success, fail, or not attempted.
  26   // Renderers do not attempt to load at at fixed address if on a
  27   // low-memory device on which browser load at fixed address has already
  28   // failed.
  29   LFA_SUCCESS = 0,
  30   LFA_BACKOFF_USED = 1,
  31   LFA_NOT_ATTEMPTED = 2,
  32
  33   // End sentinel, also used as nothing-pending indicator.
  34   MAX_RENDERER_HISTOGRAM_CODE = 3,
  35   NO_PENDING_HISTOGRAM_CODE = MAX_RENDERER_HISTOGRAM_CODE
  36 };
  37
  38 enum BrowserHistogramCode {
  39   // Non-low-memory random address browser loads.
  40   NORMAL_LRA_SUCCESS = 0,
  41
  42   // Low-memory browser loads at fixed address, success or fail.
  43   LOW_MEMORY_LFA_SUCCESS = 1,
  44   LOW_MEMORY_LFA_BACKOFF_USED = 2,
  45
  46   MAX_BROWSER_HISTOGRAM_CODE = 3,
  47 };
  48
  49 RendererHistogramCode g_renderer_histogram_code = NO_PENDING_HISTOGRAM_CODE;
  50
  51 } // namespace
  52
  53 static void RegisterChromiumAndroidLinkerRendererHistogram(
  54     JNIEnv* env,
  55     jobject jcaller,
  56     jboolean requested_shared_relro,
  57     jboolean load_at_fixed_address_failed) {
  58   // Note a pending histogram value for later recording.
  59   if (requested_shared_relro) {
  60     g_renderer_histogram_code = load_at_fixed_address_failed
  61                                 ? LFA_BACKOFF_USED : LFA_SUCCESS;
  62   } else {
  63     g_renderer_histogram_code = LFA_NOT_ATTEMPTED;
  64   }
  65 }
  66
  67 void RecordChromiumAndroidLinkerRendererHistogram() {
  68   if (g_renderer_histogram_code == NO_PENDING_HISTOGRAM_CODE)
  69     return;
  70   // Record and release the pending histogram value.
  71   UMA_HISTOGRAM_ENUMERATION("ChromiumAndroidLinker.RendererStates",
  72                             g_renderer_histogram_code,
  73                             MAX_RENDERER_HISTOGRAM_CODE);
  74   g_renderer_histogram_code = NO_PENDING_HISTOGRAM_CODE;
  75 }
  76
  77 static void RecordChromiumAndroidLinkerBrowserHistogram(
  78     JNIEnv* env,
  79     jobject jcaller,
  80     jboolean is_using_browser_shared_relros,
  81     jboolean load_at_fixed_address_failed,
  82     jint library_load_from_apk_status) {
  83   // For low-memory devices, record whether or not we successfully loaded the
  84   // browser at a fixed address. Otherwise just record a normal invocation.
  85   BrowserHistogramCode histogram_code;
  86   if (is_using_browser_shared_relros) {
  87     histogram_code = load_at_fixed_address_failed
  88                      ? LOW_MEMORY_LFA_BACKOFF_USED : LOW_MEMORY_LFA_SUCCESS;
  89   } else {
  90     histogram_code = NORMAL_LRA_SUCCESS;
  91   }
  92   UMA_HISTOGRAM_ENUMERATION("ChromiumAndroidLinker.BrowserStates",
  93                             histogram_code,
  94                             MAX_BROWSER_HISTOGRAM_CODE);
  95
  96   // Record the device support for loading a library directly from the APK file.
  97   UMA_HISTOGRAM_ENUMERATION("ChromiumAndroidLinker.LibraryLoadFromApkStatus",
  98                             library_load_from_apk_status,
  99                             LIBRARY_LOAD_FROM_APK_STATUS_CODES_MAX);
 100 }
 101
 102 void SetLibraryLoadedHook(LibraryLoadedHook* func) {
 103   g_registration_callback = func;
 104 }
 105
 106 static void InitCommandLine(JNIEnv* env,
 107                             jobject jcaller,
 108                             jobjectArray init_command_line) {
 109   InitNativeCommandLineFromJavaArray(env, init_command_line);
 110 }
 111
 112 static jboolean LibraryLoaded(JNIEnv* env, jobject jcaller) {
 113   if (g_registration_callback == NULL) {
 114     return true;
 115   }
 116   return g_registration_callback(env, NULL);
 117 }
 118
 119 void LibraryLoaderExitHook() {
 120   if (g_at_exit_manager) {
 121     delete g_at_exit_manager;
 122     g_at_exit_manager = NULL;
 123   }
 124 }
 125
 126 static jboolean ForkAndPrefetchNativeLibrary(JNIEnv* env, jclass clazz) {
 127   return NativeLibraryPrefetcher::ForkAndPrefetchNativeLibrary();
 128 }
 129
 130 bool RegisterLibraryLoaderEntryHook(JNIEnv* env) {
 131   return RegisterNativesImpl(env);
 132 }
 133
 134 void SetVersionNumber(const char* version_number) {
 135   g_library_version_number = strdup(version_number);
 136 }
 137
 138 jstring GetVersionNumber(JNIEnv* env, jobject jcaller) {
 139   return ConvertUTF8ToJavaString(env, g_library_version_number).Release();
 140 }
 141
 142 LibraryProcessType GetLibraryProcessType(JNIEnv* env) {
 143   return static_cast<LibraryProcessType>(
 144       Java_LibraryLoader_getLibraryProcessType(env));
 145 }
 146
 147 void InitAtExitManager() {
 148   g_at_exit_manager = new base::AtExitManager();
 149 }
 150
 151 }  // namespace android
 152 }  // namespace base