UserHandle.java revision a73b8fd1f4faaad00d8a49d6e496aaf249fa7003
1/* 2 * Copyright (C) 2011 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 17package android.os; 18 19import android.annotation.SystemApi; 20import android.annotation.TestApi; 21 22import java.io.PrintWriter; 23 24/** 25 * Representation of a user on the device. 26 */ 27public final class UserHandle implements Parcelable { 28 /** 29 * @hide Range of uids allocated for a user. 30 */ 31 public static final int PER_USER_RANGE = 100000; 32 33 /** @hide A user id to indicate all users on the device */ 34 public static final int USER_ALL = -1; 35 36 /** @hide A user handle to indicate all users on the device */ 37 public static final UserHandle ALL = new UserHandle(USER_ALL); 38 39 /** @hide A user id to indicate the currently active user */ 40 public static final int USER_CURRENT = -2; 41 42 /** @hide A user handle to indicate the current user of the device */ 43 public static final UserHandle CURRENT = new UserHandle(USER_CURRENT); 44 45 /** @hide A user id to indicate that we would like to send to the current 46 * user, but if this is calling from a user process then we will send it 47 * to the caller's user instead of failing with a security exception */ 48 public static final int USER_CURRENT_OR_SELF = -3; 49 50 /** @hide A user handle to indicate that we would like to send to the current 51 * user, but if this is calling from a user process then we will send it 52 * to the caller's user instead of failing with a security exception */ 53 public static final UserHandle CURRENT_OR_SELF = new UserHandle(USER_CURRENT_OR_SELF); 54 55 /** @hide An undefined user id */ 56 public static final int USER_NULL = -10000; 57 58 /** 59 * @hide A user id constant to indicate the "owner" user of the device 60 * @deprecated Consider using either {@link UserHandle#USER_SYSTEM} constant or 61 * check the target user's flag {@link android.content.pm.UserInfo#isAdmin}. 62 */ 63 public static final int USER_OWNER = 0; 64 65 /** 66 * @hide A user handle to indicate the primary/owner user of the device 67 * @deprecated Consider using either {@link UserHandle#SYSTEM} constant or 68 * check the target user's flag {@link android.content.pm.UserInfo#isAdmin}. 69 */ 70 public static final UserHandle OWNER = new UserHandle(USER_OWNER); 71 72 /** @hide A user id constant to indicate the "system" user of the device */ 73 public static final int USER_SYSTEM = 0; 74 75 /** @hide A user handle to indicate the "system" user of the device */ 76 public static final UserHandle SYSTEM = new UserHandle(USER_SYSTEM); 77 78 /** 79 * @hide Enable multi-user related side effects. Set this to false if 80 * there are problems with single user use-cases. 81 */ 82 public static final boolean MU_ENABLED = true; 83 84 final int mHandle; 85 86 /** 87 * Checks to see if the user id is the same for the two uids, i.e., they belong to the same 88 * user. 89 * @hide 90 */ 91 public static boolean isSameUser(int uid1, int uid2) { 92 return getUserId(uid1) == getUserId(uid2); 93 } 94 95 /** 96 * Checks to see if both uids are referring to the same app id, ignoring the user id part of the 97 * uids. 98 * @param uid1 uid to compare 99 * @param uid2 other uid to compare 100 * @return whether the appId is the same for both uids 101 * @hide 102 */ 103 public static boolean isSameApp(int uid1, int uid2) { 104 return getAppId(uid1) == getAppId(uid2); 105 } 106 107 /** @hide */ 108 public static boolean isIsolated(int uid) { 109 if (uid > 0) { 110 final int appId = getAppId(uid); 111 return appId >= Process.FIRST_ISOLATED_UID && appId <= Process.LAST_ISOLATED_UID; 112 } else { 113 return false; 114 } 115 } 116 117 /** @hide */ 118 public static boolean isApp(int uid) { 119 if (uid > 0) { 120 final int appId = getAppId(uid); 121 return appId >= Process.FIRST_APPLICATION_UID && appId <= Process.LAST_APPLICATION_UID; 122 } else { 123 return false; 124 } 125 } 126 127 /** 128 * Returns the user id for a given uid. 129 * @hide 130 */ 131 public static int getUserId(int uid) { 132 if (MU_ENABLED) { 133 return uid / PER_USER_RANGE; 134 } else { 135 return UserHandle.USER_SYSTEM; 136 } 137 } 138 139 /** @hide */ 140 public static int getCallingUserId() { 141 return getUserId(Binder.getCallingUid()); 142 } 143 144 /** @hide */ 145 public static UserHandle of(int userId) { 146 return userId == USER_SYSTEM ? SYSTEM : new UserHandle(userId); 147 } 148 149 /** 150 * Returns the uid that is composed from the userId and the appId. 151 * @hide 152 */ 153 public static int getUid(int userId, int appId) { 154 if (MU_ENABLED) { 155 return userId * PER_USER_RANGE + (appId % PER_USER_RANGE); 156 } else { 157 return appId; 158 } 159 } 160 161 /** 162 * Returns the app id (or base uid) for a given uid, stripping out the user id from it. 163 * @hide 164 */ 165 @TestApi 166 public static int getAppId(int uid) { 167 return uid % PER_USER_RANGE; 168 } 169 170 /** 171 * Returns the gid shared between all apps with this userId. 172 * @hide 173 */ 174 public static int getUserGid(int userId) { 175 return getUid(userId, Process.SHARED_USER_GID); 176 } 177 178 /** 179 * Returns the shared app gid for a given uid or appId. 180 * @hide 181 */ 182 public static int getSharedAppGid(int id) { 183 return Process.FIRST_SHARED_APPLICATION_GID + (id % PER_USER_RANGE) 184 - Process.FIRST_APPLICATION_UID; 185 } 186 187 /** 188 * Returns the app id for a given shared app gid. Returns -1 if the ID is invalid. 189 * @hide 190 */ 191 public static int getAppIdFromSharedAppGid(int gid) { 192 final int appId = getAppId(gid) + Process.FIRST_APPLICATION_UID 193 - Process.FIRST_SHARED_APPLICATION_GID; 194 if (appId < 0 || appId >= Process.FIRST_SHARED_APPLICATION_GID) { 195 return -1; 196 } 197 return appId; 198 } 199 200 /** 201 * Generate a text representation of the uid, breaking out its individual 202 * components -- user, app, isolated, etc. 203 * @hide 204 */ 205 public static void formatUid(StringBuilder sb, int uid) { 206 if (uid < Process.FIRST_APPLICATION_UID) { 207 sb.append(uid); 208 } else { 209 sb.append('u'); 210 sb.append(getUserId(uid)); 211 final int appId = getAppId(uid); 212 if (appId >= Process.FIRST_ISOLATED_UID && appId <= Process.LAST_ISOLATED_UID) { 213 sb.append('i'); 214 sb.append(appId - Process.FIRST_ISOLATED_UID); 215 } else if (appId >= Process.FIRST_APPLICATION_UID) { 216 sb.append('a'); 217 sb.append(appId - Process.FIRST_APPLICATION_UID); 218 } else { 219 sb.append('s'); 220 sb.append(appId); 221 } 222 } 223 } 224 225 /** 226 * Generate a text representation of the uid, breaking out its individual 227 * components -- user, app, isolated, etc. 228 * @hide 229 */ 230 public static String formatUid(int uid) { 231 StringBuilder sb = new StringBuilder(); 232 formatUid(sb, uid); 233 return sb.toString(); 234 } 235 236 /** 237 * Generate a text representation of the uid, breaking out its individual 238 * components -- user, app, isolated, etc. 239 * @hide 240 */ 241 public static void formatUid(PrintWriter pw, int uid) { 242 if (uid < Process.FIRST_APPLICATION_UID) { 243 pw.print(uid); 244 } else { 245 pw.print('u'); 246 pw.print(getUserId(uid)); 247 final int appId = getAppId(uid); 248 if (appId >= Process.FIRST_ISOLATED_UID && appId <= Process.LAST_ISOLATED_UID) { 249 pw.print('i'); 250 pw.print(appId - Process.FIRST_ISOLATED_UID); 251 } else if (appId >= Process.FIRST_APPLICATION_UID) { 252 pw.print('a'); 253 pw.print(appId - Process.FIRST_APPLICATION_UID); 254 } else { 255 pw.print('s'); 256 pw.print(appId); 257 } 258 } 259 } 260 261 /** @hide */ 262 public static int parseUserArg(String arg) { 263 int userId; 264 if ("all".equals(arg)) { 265 userId = UserHandle.USER_ALL; 266 } else if ("current".equals(arg) || "cur".equals(arg)) { 267 userId = UserHandle.USER_CURRENT; 268 } else { 269 try { 270 userId = Integer.parseInt(arg); 271 } catch (NumberFormatException e) { 272 throw new IllegalArgumentException("Bad user number: " + arg); 273 } 274 } 275 return userId; 276 } 277 278 /** 279 * Returns the user id of the current process 280 * @return user id of the current process 281 * @hide 282 */ 283 @SystemApi 284 public static int myUserId() { 285 return getUserId(Process.myUid()); 286 } 287 288 /** 289 * Returns true if this UserHandle refers to the owner user; false otherwise. 290 * @return true if this UserHandle refers to the owner user; false otherwise. 291 * @hide 292 * @deprecated please use {@link #isSystem()} or check for 293 * {@link android.content.pm.UserInfo#isPrimary()} 294 * {@link android.content.pm.UserInfo#isAdmin()} based on your particular use case. 295 */ 296 @SystemApi 297 public boolean isOwner() { 298 return this.equals(OWNER); 299 } 300 301 /** 302 * @return true if this UserHandle refers to the system user; false otherwise. 303 * @hide 304 */ 305 @SystemApi 306 public boolean isSystem() { 307 return this.equals(SYSTEM); 308 } 309 310 /** @hide */ 311 public UserHandle(int h) { 312 mHandle = h; 313 } 314 315 /** 316 * Returns the userId stored in this UserHandle. 317 * @hide 318 */ 319 @SystemApi 320 public int getIdentifier() { 321 return mHandle; 322 } 323 324 @Override 325 public String toString() { 326 return "UserHandle{" + mHandle + "}"; 327 } 328 329 @Override 330 public boolean equals(Object obj) { 331 try { 332 if (obj != null) { 333 UserHandle other = (UserHandle)obj; 334 return mHandle == other.mHandle; 335 } 336 } catch (ClassCastException e) { 337 } 338 return false; 339 } 340 341 @Override 342 public int hashCode() { 343 return mHandle; 344 } 345 346 public int describeContents() { 347 return 0; 348 } 349 350 public void writeToParcel(Parcel out, int flags) { 351 out.writeInt(mHandle); 352 } 353 354 /** 355 * Write a UserHandle to a Parcel, handling null pointers. Must be 356 * read with {@link #readFromParcel(Parcel)}. 357 * 358 * @param h The UserHandle to be written. 359 * @param out The Parcel in which the UserHandle will be placed. 360 * 361 * @see #readFromParcel(Parcel) 362 */ 363 public static void writeToParcel(UserHandle h, Parcel out) { 364 if (h != null) { 365 h.writeToParcel(out, 0); 366 } else { 367 out.writeInt(USER_NULL); 368 } 369 } 370 371 /** 372 * Read a UserHandle from a Parcel that was previously written 373 * with {@link #writeToParcel(UserHandle, Parcel)}, returning either 374 * a null or new object as appropriate. 375 * 376 * @param in The Parcel from which to read the UserHandle 377 * @return Returns a new UserHandle matching the previously written 378 * object, or null if a null had been written. 379 * 380 * @see #writeToParcel(UserHandle, Parcel) 381 */ 382 public static UserHandle readFromParcel(Parcel in) { 383 int h = in.readInt(); 384 return h != USER_NULL ? new UserHandle(h) : null; 385 } 386 387 public static final Parcelable.Creator<UserHandle> CREATOR 388 = new Parcelable.Creator<UserHandle>() { 389 public UserHandle createFromParcel(Parcel in) { 390 return new UserHandle(in); 391 } 392 393 public UserHandle[] newArray(int size) { 394 return new UserHandle[size]; 395 } 396 }; 397 398 /** 399 * Instantiate a new UserHandle from the data in a Parcel that was 400 * previously written with {@link #writeToParcel(Parcel, int)}. Note that you 401 * must not use this with data written by 402 * {@link #writeToParcel(UserHandle, Parcel)} since it is not possible 403 * to handle a null UserHandle here. 404 * 405 * @param in The Parcel containing the previously written UserHandle, 406 * positioned at the location in the buffer where it was written. 407 */ 408 public UserHandle(Parcel in) { 409 mHandle = in.readInt(); 410 } 411} 412