1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.server; 18 19 import android.content.ContentResolver; 20 import android.os.DropBoxManager; 21 import android.os.FileObserver; 22 import android.os.Binder; 23 24 import android.util.Slog; 25 import android.content.Context; 26 import android.database.ContentObserver; 27 import android.os.SystemProperties; 28 import android.provider.Settings; 29 import com.android.internal.os.SamplingProfilerIntegration; 30 31 import java.io.File; 32 import java.io.FileDescriptor; 33 import java.io.IOException; 34 import java.io.PrintWriter; 35 36 public class SamplingProfilerService extends Binder { 37 38 private static final String TAG = "SamplingProfilerService"; 39 private static final boolean LOCAL_LOGV = false; 40 public static final String SNAPSHOT_DIR = SamplingProfilerIntegration.SNAPSHOT_DIR; 41 42 private final Context mContext; 43 private FileObserver snapshotObserver; 44 SamplingProfilerService(Context context)45 public SamplingProfilerService(Context context) { 46 mContext = context; 47 registerSettingObserver(context); 48 startWorking(context); 49 } 50 startWorking(Context context)51 private void startWorking(Context context) { 52 if (LOCAL_LOGV) Slog.v(TAG, "starting SamplingProfilerService!"); 53 54 final DropBoxManager dropbox = 55 (DropBoxManager) context.getSystemService(Context.DROPBOX_SERVICE); 56 57 // before FileObserver is ready, there could have already been some snapshots 58 // in the directory, we don't want to miss them 59 File[] snapshotFiles = new File(SNAPSHOT_DIR).listFiles(); 60 for (int i = 0; snapshotFiles != null && i < snapshotFiles.length; i++) { 61 handleSnapshotFile(snapshotFiles[i], dropbox); 62 } 63 64 // detect new snapshot and put it in dropbox 65 // delete it afterwards no matter what happened before 66 // Note: needs listening at event ATTRIB rather than CLOSE_WRITE, because we set the 67 // readability of snapshot files after writing them! 68 snapshotObserver = new FileObserver(SNAPSHOT_DIR, FileObserver.ATTRIB) { 69 @Override 70 public void onEvent(int event, String path) { 71 handleSnapshotFile(new File(SNAPSHOT_DIR, path), dropbox); 72 } 73 }; 74 snapshotObserver.startWatching(); 75 76 if (LOCAL_LOGV) Slog.v(TAG, "SamplingProfilerService activated"); 77 } 78 handleSnapshotFile(File file, DropBoxManager dropbox)79 private void handleSnapshotFile(File file, DropBoxManager dropbox) { 80 try { 81 dropbox.addFile(TAG, file, 0); 82 if (LOCAL_LOGV) Slog.v(TAG, file.getPath() + " added to dropbox"); 83 } catch (IOException e) { 84 Slog.e(TAG, "Can't add " + file.getPath() + " to dropbox", e); 85 } finally { 86 file.delete(); 87 } 88 } 89 registerSettingObserver(Context context)90 private void registerSettingObserver(Context context) { 91 ContentResolver contentResolver = context.getContentResolver(); 92 contentResolver.registerContentObserver( 93 Settings.Global.getUriFor(Settings.Global.SAMPLING_PROFILER_MS), 94 false, new SamplingProfilerSettingsObserver(contentResolver)); 95 } 96 97 @Override dump(FileDescriptor fd, PrintWriter pw, String[] args)98 protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) { 99 mContext.enforceCallingOrSelfPermission(android.Manifest.permission.DUMP, TAG); 100 101 pw.println("SamplingProfilerService:"); 102 pw.println("Watching directory: " + SNAPSHOT_DIR); 103 } 104 105 private class SamplingProfilerSettingsObserver extends ContentObserver { 106 private ContentResolver mContentResolver; SamplingProfilerSettingsObserver(ContentResolver contentResolver)107 public SamplingProfilerSettingsObserver(ContentResolver contentResolver) { 108 super(null); 109 mContentResolver = contentResolver; 110 onChange(false); 111 } 112 @Override onChange(boolean selfChange)113 public void onChange(boolean selfChange) { 114 Integer samplingProfilerMs = Settings.Global.getInt( 115 mContentResolver, Settings.Global.SAMPLING_PROFILER_MS, 0); 116 // setting this secure property will start or stop sampling profiler, 117 // as well as adjust the the time between taking snapshots. 118 SystemProperties.set("persist.sys.profiler_ms", samplingProfilerMs.toString()); 119 } 120 } 121 } 122