The Android Open Source Project | 9066cfe | 2009-03-03 19:31:44 -0800 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2007-2008 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 com.android.server.am.ActivityManagerService; |
| 20 | import android.app.Notification; |
| 21 | import android.app.NotificationManager; |
| 22 | import android.app.PendingIntent; |
| 23 | import android.content.ContentResolver; |
| 24 | import android.content.Context; |
| 25 | import android.content.Intent; |
| 26 | import android.content.pm.IPackageDataObserver; |
| 27 | import android.content.pm.IPackageManager; |
| 28 | import android.os.Binder; |
| 29 | import android.os.Handler; |
| 30 | import android.os.Message; |
| 31 | import android.os.Process; |
| 32 | import android.os.RemoteException; |
| 33 | import android.os.ServiceManager; |
| 34 | import android.os.StatFs; |
| 35 | import android.os.SystemClock; |
| 36 | import android.os.SystemProperties; |
| 37 | import android.provider.Settings.Gservices; |
| 38 | import android.util.Config; |
| 39 | import android.util.EventLog; |
| 40 | import android.util.Log; |
| 41 | import android.provider.Settings; |
| 42 | |
| 43 | /** |
| 44 | * This class implements a service to monitor the amount of disk storage space |
| 45 | * on the device. If the free storage on device is less than a tunable threshold value |
| 46 | * (default is 10%. this value is a gservices parameter) a low memory notification is |
| 47 | * displayed to alert the user. If the user clicks on the low memory notification the |
| 48 | * Application Manager application gets launched to let the user free storage space. |
| 49 | * Event log events: |
| 50 | * A low memory event with the free storage on device in bytes is logged to the event log |
| 51 | * when the device goes low on storage space. |
| 52 | * The amount of free storage on the device is periodically logged to the event log. The log |
| 53 | * interval is a gservices parameter with a default value of 12 hours |
| 54 | * When the free storage differential goes below a threshold(again a gservices parameter with |
| 55 | * a default value of 2MB), the free memory is logged to the event log |
| 56 | */ |
| 57 | class DeviceStorageMonitorService extends Binder { |
| 58 | private static final String TAG = "DeviceStorageMonitorService"; |
| 59 | private static final boolean DEBUG = false; |
| 60 | private static final boolean localLOGV = DEBUG ? Config.LOGD : Config.LOGV; |
| 61 | private static final int DEVICE_MEMORY_WHAT = 1; |
| 62 | private static final int MONITOR_INTERVAL = 1; //in minutes |
| 63 | private static final int LOW_MEMORY_NOTIFICATION_ID = 1; |
| 64 | private static final int DEFAULT_THRESHOLD_PERCENTAGE = 10; |
| 65 | private static final int DEFAULT_FREE_STORAGE_LOG_INTERVAL_IN_MINUTES = 12*60; //in minutes |
| 66 | private static final int EVENT_LOG_STORAGE_BELOW_THRESHOLD = 2744; |
| 67 | private static final int EVENT_LOG_LOW_STORAGE_NOTIFICATION = 2745; |
| 68 | private static final int EVENT_LOG_FREE_STORAGE_LEFT = 2746; |
| 69 | private static final long DEFAULT_DISK_FREE_CHANGE_REPORTING_THRESHOLD = 2 * 1024 * 1024; // 2MB |
| 70 | private static final long DEFAULT_CHECK_INTERVAL = MONITOR_INTERVAL*60*1000; |
| 71 | private long mFreeMem; |
| 72 | private long mLastReportedFreeMem; |
| 73 | private long mLastReportedFreeMemTime; |
| 74 | private boolean mLowMemFlag=false; |
| 75 | private Context mContext; |
| 76 | private ContentResolver mContentResolver; |
| 77 | int mBlkSize; |
| 78 | long mTotalMemory; |
| 79 | StatFs mFileStats; |
| 80 | private static final String DATA_PATH="/data"; |
| 81 | long mThreadStartTime = -1; |
| 82 | boolean mClearSucceeded = false; |
| 83 | boolean mClearingCache; |
| 84 | private Intent mStorageLowIntent; |
| 85 | private Intent mStorageOkIntent; |
| 86 | private CachePackageDataObserver mClearCacheObserver; |
| 87 | private static final int _TRUE = 1; |
| 88 | private static final int _FALSE = 0; |
| 89 | |
| 90 | /** |
| 91 | * This string is used for ServiceManager access to this class. |
| 92 | */ |
| 93 | static final String SERVICE = "devicestoragemonitor"; |
| 94 | |
| 95 | /** |
| 96 | * Handler that checks the amount of disk space on the device and sends a |
| 97 | * notification if the device runs low on disk space |
| 98 | */ |
| 99 | Handler mHandler = new Handler() { |
| 100 | @Override |
| 101 | public void handleMessage(Message msg) { |
| 102 | //dont handle an invalid message |
| 103 | if (msg.what != DEVICE_MEMORY_WHAT) { |
| 104 | Log.e(TAG, "Will not process invalid message"); |
| 105 | return; |
| 106 | } |
| 107 | checkMemory(msg.arg1 == _TRUE); |
| 108 | } |
| 109 | }; |
| 110 | |
| 111 | class CachePackageDataObserver extends IPackageDataObserver.Stub { |
| 112 | public void onRemoveCompleted(String packageName, boolean succeeded) { |
| 113 | mClearSucceeded = succeeded; |
| 114 | mClearingCache = false; |
| 115 | if(localLOGV) Log.i(TAG, " Clear succeeded:"+mClearSucceeded |
| 116 | +", mClearingCache:"+mClearingCache+" Forcing memory check"); |
| 117 | postCheckMemoryMsg(false, 0); |
| 118 | } |
| 119 | } |
| 120 | |
| 121 | private final void restatDataDir() { |
| 122 | mFileStats.restat(DATA_PATH); |
| 123 | mFreeMem = mFileStats.getAvailableBlocks()*mBlkSize; |
| 124 | // Allow freemem to be overridden by debug.freemem for testing |
| 125 | String debugFreeMem = SystemProperties.get("debug.freemem"); |
| 126 | if (!"".equals(debugFreeMem)) { |
| 127 | mFreeMem = Long.parseLong(debugFreeMem); |
| 128 | } |
| 129 | // Read the log interval from Gservices |
| 130 | long freeMemLogInterval = Gservices.getLong(mContentResolver, |
| 131 | Gservices.SYS_FREE_STORAGE_LOG_INTERVAL, |
| 132 | DEFAULT_FREE_STORAGE_LOG_INTERVAL_IN_MINUTES)*60*1000; |
| 133 | //log the amount of free memory in event log |
| 134 | long currTime = SystemClock.elapsedRealtime(); |
| 135 | if((mLastReportedFreeMemTime == 0) || |
| 136 | (currTime-mLastReportedFreeMemTime) >= freeMemLogInterval) { |
| 137 | mLastReportedFreeMemTime = currTime; |
| 138 | EventLog.writeEvent(EVENT_LOG_FREE_STORAGE_LEFT, mFreeMem); |
| 139 | } |
| 140 | // Read the reporting threshold from Gservices |
| 141 | long threshold = Gservices.getLong(mContentResolver, |
| 142 | Gservices.DISK_FREE_CHANGE_REPORTING_THRESHOLD, |
| 143 | DEFAULT_DISK_FREE_CHANGE_REPORTING_THRESHOLD); |
| 144 | // If mFree changed significantly log the new value |
| 145 | long delta = mFreeMem - mLastReportedFreeMem; |
| 146 | if (delta > threshold || delta < -threshold) { |
| 147 | mLastReportedFreeMem = mFreeMem; |
| 148 | EventLog.writeEvent(EVENT_LOG_STORAGE_BELOW_THRESHOLD, mFreeMem); |
| 149 | } |
| 150 | } |
| 151 | |
| 152 | private final void clearCache() { |
| 153 | if (mClearCacheObserver == null) { |
| 154 | // Lazy instantiation |
| 155 | mClearCacheObserver = new CachePackageDataObserver(); |
| 156 | } |
| 157 | mClearingCache = true; |
| 158 | try { |
| 159 | if (localLOGV) Log.i(TAG, "Clearing cache"); |
| 160 | IPackageManager.Stub.asInterface(ServiceManager.getService("package")). |
| 161 | freeStorageAndNotify(getMemThreshold(), mClearCacheObserver); |
| 162 | } catch (RemoteException e) { |
| 163 | Log.w(TAG, "Failed to get handle for PackageManger Exception: "+e); |
| 164 | mClearingCache = false; |
| 165 | mClearSucceeded = false; |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | private final void checkMemory(boolean checkCache) { |
| 170 | //if the thread that was started to clear cache is still running do nothing till its |
| 171 | //finished clearing cache. Ideally this flag could be modified by clearCache |
| 172 | // and should be accessed via a lock but even if it does this test will fail now and |
| 173 | //hopefully the next time this flag will be set to the correct value. |
| 174 | if(mClearingCache) { |
| 175 | if(localLOGV) Log.i(TAG, "Thread already running just skip"); |
| 176 | //make sure the thread is not hung for too long |
| 177 | long diffTime = System.currentTimeMillis() - mThreadStartTime; |
| 178 | if(diffTime > (10*60*1000)) { |
| 179 | Log.w(TAG, "Thread that clears cache file seems to run for ever"); |
| 180 | } |
| 181 | } else { |
| 182 | restatDataDir(); |
| 183 | if (localLOGV) Log.v(TAG, "freeMemory="+mFreeMem); |
| 184 | |
| 185 | //post intent to NotificationManager to display icon if necessary |
| 186 | long memThreshold = getMemThreshold(); |
| 187 | if (mFreeMem < memThreshold) { |
| 188 | if (!mLowMemFlag) { |
| 189 | if (checkCache) { |
| 190 | // See if clearing cache helps |
| 191 | // Note that clearing cache is asynchronous and so we do a |
| 192 | // memory check again once the cache has been cleared. |
| 193 | mThreadStartTime = System.currentTimeMillis(); |
| 194 | mClearSucceeded = false; |
| 195 | clearCache(); |
| 196 | } else { |
| 197 | Log.i(TAG, "Running low on memory. Sending notification"); |
| 198 | sendNotification(); |
| 199 | mLowMemFlag = true; |
| 200 | } |
| 201 | } else { |
| 202 | if (localLOGV) Log.v(TAG, "Running low on memory " + |
| 203 | "notification already sent. do nothing"); |
| 204 | } |
| 205 | } else { |
| 206 | if (mLowMemFlag) { |
| 207 | Log.i(TAG, "Memory available. Cancelling notification"); |
| 208 | cancelNotification(); |
| 209 | mLowMemFlag = false; |
| 210 | } |
| 211 | } |
| 212 | } |
| 213 | if(localLOGV) Log.i(TAG, "Posting Message again"); |
| 214 | //keep posting messages to itself periodically |
| 215 | postCheckMemoryMsg(true, DEFAULT_CHECK_INTERVAL); |
| 216 | } |
| 217 | |
| 218 | private void postCheckMemoryMsg(boolean clearCache, long delay) { |
| 219 | // Remove queued messages |
| 220 | mHandler.removeMessages(DEVICE_MEMORY_WHAT); |
| 221 | mHandler.sendMessageDelayed(mHandler.obtainMessage(DEVICE_MEMORY_WHAT, |
| 222 | clearCache ?_TRUE : _FALSE, 0), |
| 223 | delay); |
| 224 | } |
| 225 | |
| 226 | /* |
| 227 | * just query settings to retrieve the memory threshold. |
| 228 | * Preferred this over using a ContentObserver since Settings.Gservices caches the value |
| 229 | * any way |
| 230 | */ |
| 231 | private long getMemThreshold() { |
| 232 | int value = Settings.Gservices.getInt( |
| 233 | mContentResolver, |
| 234 | Settings.Gservices.SYS_STORAGE_THRESHOLD_PERCENTAGE, |
| 235 | DEFAULT_THRESHOLD_PERCENTAGE); |
| 236 | if(localLOGV) Log.v(TAG, "Threshold Percentage="+value); |
| 237 | //evaluate threshold value |
| 238 | return mTotalMemory*value; |
| 239 | } |
| 240 | |
| 241 | /** |
| 242 | * Constructor to run service. initializes the disk space threshold value |
| 243 | * and posts an empty message to kickstart the process. |
| 244 | */ |
| 245 | public DeviceStorageMonitorService(Context context) { |
| 246 | mLastReportedFreeMemTime = 0; |
| 247 | mContext = context; |
| 248 | mContentResolver = mContext.getContentResolver(); |
| 249 | //create StatFs object |
| 250 | mFileStats = new StatFs(DATA_PATH); |
| 251 | //initialize block size |
| 252 | mBlkSize = mFileStats.getBlockSize(); |
| 253 | //initialize total storage on device |
| 254 | mTotalMemory = (mFileStats.getBlockCount()*mBlkSize)/100; |
| 255 | mStorageLowIntent = new Intent(Intent.ACTION_DEVICE_STORAGE_LOW); |
| 256 | mStorageOkIntent = new Intent(Intent.ACTION_DEVICE_STORAGE_OK); |
| 257 | checkMemory(true); |
| 258 | } |
| 259 | |
| 260 | |
| 261 | /** |
| 262 | * This method sends a notification to NotificationManager to display |
| 263 | * an error dialog indicating low disk space and launch the Installer |
| 264 | * application |
| 265 | */ |
| 266 | private final void sendNotification() { |
| 267 | if(localLOGV) Log.i(TAG, "Sending low memory notification"); |
| 268 | //log the event to event log with the amount of free storage(in bytes) left on the device |
| 269 | EventLog.writeEvent(EVENT_LOG_LOW_STORAGE_NOTIFICATION, mFreeMem); |
| 270 | // Pack up the values and broadcast them to everyone |
| 271 | Intent lowMemIntent = new Intent(Intent.ACTION_MANAGE_PACKAGE_STORAGE); |
| 272 | lowMemIntent.putExtra("memory", mFreeMem); |
| 273 | lowMemIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); |
| 274 | NotificationManager mNotificationMgr = |
| 275 | (NotificationManager)mContext.getSystemService( |
| 276 | Context.NOTIFICATION_SERVICE); |
| 277 | CharSequence title = mContext.getText( |
| 278 | com.android.internal.R.string.low_internal_storage_view_title); |
| 279 | CharSequence details = mContext.getText( |
| 280 | com.android.internal.R.string.low_internal_storage_view_text); |
| 281 | PendingIntent intent = PendingIntent.getActivity(mContext, 0, lowMemIntent, 0); |
| 282 | Notification notification = new Notification(); |
| 283 | notification.icon = com.android.internal.R.drawable.stat_notify_disk_full; |
| 284 | notification.tickerText = title; |
| 285 | notification.flags |= Notification.FLAG_NO_CLEAR; |
| 286 | notification.setLatestEventInfo(mContext, title, details, intent); |
| 287 | mNotificationMgr.notify(LOW_MEMORY_NOTIFICATION_ID, notification); |
| 288 | mContext.sendStickyBroadcast(mStorageLowIntent); |
| 289 | } |
| 290 | |
| 291 | /** |
| 292 | * Cancels low storage notification and sends OK intent. |
| 293 | */ |
| 294 | private final void cancelNotification() { |
| 295 | if(localLOGV) Log.i(TAG, "Canceling low memory notification"); |
| 296 | NotificationManager mNotificationMgr = |
| 297 | (NotificationManager)mContext.getSystemService( |
| 298 | Context.NOTIFICATION_SERVICE); |
| 299 | //cancel notification since memory has been freed |
| 300 | mNotificationMgr.cancel(LOW_MEMORY_NOTIFICATION_ID); |
| 301 | |
| 302 | mContext.removeStickyBroadcast(mStorageLowIntent); |
| 303 | mContext.sendBroadcast(mStorageOkIntent); |
| 304 | } |
| 305 | |
| 306 | public void updateMemory() { |
| 307 | int callingUid = getCallingUid(); |
| 308 | if(callingUid != Process.SYSTEM_UID) { |
| 309 | return; |
| 310 | } |
| 311 | // force an early check |
| 312 | postCheckMemoryMsg(true, 0); |
| 313 | } |
| 314 | } |