1 /* 2 * Copyright (C) 2009 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 android.os; 18 19 import android.util.Log; 20 21 import com.android.internal.os.IDropBoxManagerService; 22 23 import java.io.ByteArrayInputStream; 24 import java.io.Closeable; 25 import java.io.File; 26 import java.io.FileInputStream; 27 import java.io.IOException; 28 import java.io.InputStream; 29 import java.util.zip.GZIPInputStream; 30 31 /** 32 * Enqueues chunks of data (from various sources -- application crashes, kernel 33 * log records, etc.). The queue is size bounded and will drop old data if the 34 * enqueued data exceeds the maximum size. You can think of this as a 35 * persistent, system-wide, blob-oriented "logcat". 36 * 37 * <p>You can obtain an instance of this class by calling 38 * {@link android.content.Context#getSystemService} 39 * with {@link android.content.Context#DROPBOX_SERVICE}. 40 * 41 * <p>DropBoxManager entries are not sent anywhere directly, but other system 42 * services and debugging tools may scan and upload entries for processing. 43 */ 44 public class DropBoxManager { 45 private static final String TAG = "DropBoxManager"; 46 private final IDropBoxManagerService mService; 47 48 /** Flag value: Entry's content was deleted to save space. */ 49 public static final int IS_EMPTY = 1; 50 51 /** Flag value: Content is human-readable UTF-8 text (can be combined with IS_GZIPPED). */ 52 public static final int IS_TEXT = 2; 53 54 /** Flag value: Content can be decompressed with {@link java.util.zip.GZIPOutputStream}. */ 55 public static final int IS_GZIPPED = 4; 56 57 /** Flag value for serialization only: Value is a byte array, not a file descriptor */ 58 private static final int HAS_BYTE_ARRAY = 8; 59 60 /** 61 * Broadcast Action: This is broadcast when a new entry is added in the dropbox. 62 * You must hold the {@link android.Manifest.permission#READ_LOGS} permission 63 * in order to receive this broadcast. 64 * 65 * <p class="note">This is a protected intent that can only be sent 66 * by the system. 67 */ 68 public static final String ACTION_DROPBOX_ENTRY_ADDED = 69 "android.intent.action.DROPBOX_ENTRY_ADDED"; 70 71 /** 72 * Extra for {@link android.os.DropBoxManager#ACTION_DROPBOX_ENTRY_ADDED}: 73 * string containing the dropbox tag. 74 */ 75 public static final String EXTRA_TAG = "tag"; 76 77 /** 78 * Extra for {@link android.os.DropBoxManager#ACTION_DROPBOX_ENTRY_ADDED}: 79 * long integer value containing time (in milliseconds since January 1, 1970 00:00:00 UTC) 80 * when the entry was created. 81 */ 82 public static final String EXTRA_TIME = "time"; 83 84 /** 85 * A single entry retrieved from the drop box. 86 * This may include a reference to a stream, so you must call 87 * {@link #close()} when you are done using it. 88 */ 89 public static class Entry implements Parcelable, Closeable { 90 private final String mTag; 91 private final long mTimeMillis; 92 93 private final byte[] mData; 94 private final ParcelFileDescriptor mFileDescriptor; 95 private final int mFlags; 96 97 /** Create a new empty Entry with no contents. */ 98 public Entry(String tag, long millis) { 99 if (tag == null) throw new NullPointerException("tag == null"); 100 101 mTag = tag; 102 mTimeMillis = millis; 103 mData = null; 104 mFileDescriptor = null; 105 mFlags = IS_EMPTY; 106 } 107 108 /** Create a new Entry with plain text contents. */ 109 public Entry(String tag, long millis, String text) { 110 if (tag == null) throw new NullPointerException("tag == null"); 111 if (text == null) throw new NullPointerException("text == null"); 112 113 mTag = tag; 114 mTimeMillis = millis; 115 mData = text.getBytes(); 116 mFileDescriptor = null; 117 mFlags = IS_TEXT; 118 } 119 120 /** 121 * Create a new Entry with byte array contents. 122 * The data array must not be modified after creating this entry. 123 */ 124 public Entry(String tag, long millis, byte[] data, int flags) { 125 if (tag == null) throw new NullPointerException("tag == null"); 126 if (((flags & IS_EMPTY) != 0) != (data == null)) { 127 throw new IllegalArgumentException("Bad flags: " + flags); 128 } 129 130 mTag = tag; 131 mTimeMillis = millis; 132 mData = data; 133 mFileDescriptor = null; 134 mFlags = flags; 135 } 136 137 /** 138 * Create a new Entry with streaming data contents. 139 * Takes ownership of the ParcelFileDescriptor. 140 */ 141 public Entry(String tag, long millis, ParcelFileDescriptor data, int flags) { 142 if (tag == null) throw new NullPointerException("tag == null"); 143 if (((flags & IS_EMPTY) != 0) != (data == null)) { 144 throw new IllegalArgumentException("Bad flags: " + flags); 145 } 146 147 mTag = tag; 148 mTimeMillis = millis; 149 mData = null; 150 mFileDescriptor = data; 151 mFlags = flags; 152 } 153 154 /** 155 * Create a new Entry with the contents read from a file. 156 * The file will be read when the entry's contents are requested. 157 */ 158 public Entry(String tag, long millis, File data, int flags) throws IOException { 159 if (tag == null) throw new NullPointerException("tag == null"); 160 if ((flags & IS_EMPTY) != 0) throw new IllegalArgumentException("Bad flags: " + flags); 161 162 mTag = tag; 163 mTimeMillis = millis; 164 mData = null; 165 mFileDescriptor = ParcelFileDescriptor.open(data, ParcelFileDescriptor.MODE_READ_ONLY); 166 mFlags = flags; 167 } 168 169 /** Close the input stream associated with this entry. */ 170 public void close() { 171 try { if (mFileDescriptor != null) mFileDescriptor.close(); } catch (IOException e) { } 172 } 173 174 /** @return the tag originally attached to the entry. */ 175 public String getTag() { return mTag; } 176 177 /** @return time when the entry was originally created. */ 178 public long getTimeMillis() { return mTimeMillis; } 179 180 /** @return flags describing the content returned by {@link #getInputStream()}. */ 181 public int getFlags() { return mFlags & ~IS_GZIPPED; } // getInputStream() decompresses. 182 183 /** 184 * @param maxBytes of string to return (will truncate at this length). 185 * @return the uncompressed text contents of the entry, null if the entry is not text. 186 */ 187 public String getText(int maxBytes) { 188 if ((mFlags & IS_TEXT) == 0) return null; 189 if (mData != null) return new String(mData, 0, Math.min(maxBytes, mData.length)); 190 191 InputStream is = null; 192 try { 193 is = getInputStream(); 194 if (is == null) return null; 195 byte[] buf = new byte[maxBytes]; 196 int readBytes = 0; 197 int n = 0; 198 while (n >= 0 && (readBytes += n) < maxBytes) { 199 n = is.read(buf, readBytes, maxBytes - readBytes); 200 } 201 return new String(buf, 0, readBytes); 202 } catch (IOException e) { 203 return null; 204 } finally { 205 try { if (is != null) is.close(); } catch (IOException e) {} 206 } 207 } 208 209 /** @return the uncompressed contents of the entry, or null if the contents were lost */ 210 public InputStream getInputStream() throws IOException { 211 InputStream is; 212 if (mData != null) { 213 is = new ByteArrayInputStream(mData); 214 } else if (mFileDescriptor != null) { 215 is = new ParcelFileDescriptor.AutoCloseInputStream(mFileDescriptor); 216 } else { 217 return null; 218 } 219 return (mFlags & IS_GZIPPED) != 0 ? new GZIPInputStream(is) : is; 220 } 221 222 public static final Parcelable.Creator<Entry> CREATOR = new Parcelable.Creator() { 223 public Entry[] newArray(int size) { return new Entry[size]; } 224 public Entry createFromParcel(Parcel in) { 225 String tag = in.readString(); 226 long millis = in.readLong(); 227 int flags = in.readInt(); 228 if ((flags & HAS_BYTE_ARRAY) != 0) { 229 return new Entry(tag, millis, in.createByteArray(), flags & ~HAS_BYTE_ARRAY); 230 } else { 231 return new Entry(tag, millis, in.readFileDescriptor(), flags); 232 } 233 } 234 }; 235 236 public int describeContents() { 237 return mFileDescriptor != null ? Parcelable.CONTENTS_FILE_DESCRIPTOR : 0; 238 } 239 240 public void writeToParcel(Parcel out, int flags) { 241 out.writeString(mTag); 242 out.writeLong(mTimeMillis); 243 if (mFileDescriptor != null) { 244 out.writeInt(mFlags & ~HAS_BYTE_ARRAY); // Clear bit just to be safe 245 mFileDescriptor.writeToParcel(out, flags); 246 } else { 247 out.writeInt(mFlags | HAS_BYTE_ARRAY); 248 out.writeByteArray(mData); 249 } 250 } 251 } 252 253 /** {@hide} */ 254 public DropBoxManager(IDropBoxManagerService service) { mService = service; } 255 256 /** 257 * Create a dummy instance for testing. All methods will fail unless 258 * overridden with an appropriate mock implementation. To obtain a 259 * functional instance, use {@link android.content.Context#getSystemService}. 260 */ 261 protected DropBoxManager() { mService = null; } 262 263 /** 264 * Stores human-readable text. The data may be discarded eventually (or even 265 * immediately) if space is limited, or ignored entirely if the tag has been 266 * blocked (see {@link #isTagEnabled}). 267 * 268 * @param tag describing the type of entry being stored 269 * @param data value to store 270 */ 271 public void addText(String tag, String data) { 272 try { mService.add(new Entry(tag, 0, data)); } catch (RemoteException e) {} 273 } 274 275 /** 276 * Stores binary data, which may be ignored or discarded as with {@link #addText}. 277 * 278 * @param tag describing the type of entry being stored 279 * @param data value to store 280 * @param flags describing the data 281 */ 282 public void addData(String tag, byte[] data, int flags) { 283 if (data == null) throw new NullPointerException("data == null"); 284 try { mService.add(new Entry(tag, 0, data, flags)); } catch (RemoteException e) {} 285 } 286 287 /** 288 * Stores the contents of a file, which may be ignored or discarded as with 289 * {@link #addText}. 290 * 291 * @param tag describing the type of entry being stored 292 * @param file to read from 293 * @param flags describing the data 294 * @throws IOException if the file can't be opened 295 */ 296 public void addFile(String tag, File file, int flags) throws IOException { 297 if (file == null) throw new NullPointerException("file == null"); 298 Entry entry = new Entry(tag, 0, file, flags); 299 try { 300 mService.add(entry); 301 } catch (RemoteException e) { 302 // ignore 303 } finally { 304 entry.close(); 305 } 306 } 307 308 /** 309 * Checks any blacklists (set in system settings) to see whether a certain 310 * tag is allowed. Entries with disabled tags will be dropped immediately, 311 * so you can save the work of actually constructing and sending the data. 312 * 313 * @param tag that would be used in {@link #addText} or {@link #addFile} 314 * @return whether events with that tag would be accepted 315 */ 316 public boolean isTagEnabled(String tag) { 317 try { return mService.isTagEnabled(tag); } catch (RemoteException e) { return false; } 318 } 319 320 /** 321 * Gets the next entry from the drop box <em>after</em> the specified time. 322 * Requires <code>android.permission.READ_LOGS</code>. You must always call 323 * {@link Entry#close()} on the return value! 324 * 325 * @param tag of entry to look for, null for all tags 326 * @param msec time of the last entry seen 327 * @return the next entry, or null if there are no more entries 328 */ 329 public Entry getNextEntry(String tag, long msec) { 330 try { return mService.getNextEntry(tag, msec); } catch (RemoteException e) { return null; } 331 } 332 333 // TODO: It may be useful to have some sort of notification mechanism 334 // when data is added to the dropbox, for demand-driven readers -- 335 // for now readers need to poll the dropbox to find new data. 336 } 337
