1 /*
2  * Copyright (C) 2013 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.provider;
18 
19 import static android.net.TrafficStats.KB_IN_BYTES;
20 import static android.system.OsConstants.SEEK_SET;
21 
22 import android.content.ContentProviderClient;
23 import android.content.ContentResolver;
24 import android.content.Context;
25 import android.content.Intent;
26 import android.content.pm.ResolveInfo;
27 import android.content.res.AssetFileDescriptor;
28 import android.database.Cursor;
29 import android.graphics.Bitmap;
30 import android.graphics.BitmapFactory;
31 import android.graphics.Matrix;
32 import android.graphics.Point;
33 import android.media.ExifInterface;
34 import android.net.Uri;
35 import android.os.Bundle;
36 import android.os.CancellationSignal;
37 import android.os.OperationCanceledException;
38 import android.os.ParcelFileDescriptor;
39 import android.os.ParcelFileDescriptor.OnCloseListener;
40 import android.os.RemoteException;
41 import android.system.ErrnoException;
42 import android.system.Os;
43 import android.util.Log;
44 
45 import libcore.io.IoUtils;
46 
47 import java.io.BufferedInputStream;
48 import java.io.File;
49 import java.io.FileDescriptor;
50 import java.io.FileInputStream;
51 import java.io.FileNotFoundException;
52 import java.io.IOException;
53 import java.util.List;
54 
55 /**
56  * Defines the contract between a documents provider and the platform.
57  * <p>
58  * To create a document provider, extend {@link DocumentsProvider}, which
59  * provides a foundational implementation of this contract.
60  * <p>
61  * All client apps must hold a valid URI permission grant to access documents,
62  * typically issued when a user makes a selection through
63  * {@link Intent#ACTION_OPEN_DOCUMENT}, {@link Intent#ACTION_CREATE_DOCUMENT},
64  * or {@link Intent#ACTION_OPEN_DOCUMENT_TREE}.
65  *
66  * @see DocumentsProvider
67  */
68 public final class DocumentsContract {
69     private static final String TAG = "Documents";
70 
71     // content://com.example/root/
72     // content://com.example/root/sdcard/
73     // content://com.example/root/sdcard/recent/
74     // content://com.example/root/sdcard/search/?query=pony
75     // content://com.example/document/12/
76     // content://com.example/document/12/children/
77     // content://com.example/tree/12/document/24/
78     // content://com.example/tree/12/document/24/children/
79 
DocumentsContract()80     private DocumentsContract() {
81     }
82 
83     /**
84      * Intent action used to identify {@link DocumentsProvider} instances. This
85      * is used in the {@code <intent-filter>} of a {@code <provider>}.
86      */
87     public static final String PROVIDER_INTERFACE = "android.content.action.DOCUMENTS_PROVIDER";
88 
89     /** {@hide} */
90     public static final String EXTRA_PACKAGE_NAME = "android.content.extra.PACKAGE_NAME";
91 
92     /** {@hide} */
93     public static final String EXTRA_SHOW_ADVANCED = "android.content.extra.SHOW_ADVANCED";
94 
95     /**
96      * Set this in a DocumentsUI intent to cause a package's own roots to be
97      * excluded from the roots list.
98      */
99     public static final String EXTRA_EXCLUDE_SELF = "android.provider.extra.EXCLUDE_SELF";
100 
101     /**
102      * Included in {@link AssetFileDescriptor#getExtras()} when returned
103      * thumbnail should be rotated.
104      *
105      * @see MediaStore.Images.ImageColumns#ORIENTATION
106      * @hide
107      */
108     public static final String EXTRA_ORIENTATION = "android.content.extra.ORIENTATION";
109 
110     /**
111      * Overrides the default prompt text in DocumentsUI when set in an intent.
112      */
113     public static final String EXTRA_PROMPT = "android.provider.extra.PROMPT";
114 
115     /** {@hide} */
116     public static final String ACTION_MANAGE_ROOT = "android.provider.action.MANAGE_ROOT";
117     /** {@hide} */
118     public static final String ACTION_MANAGE_DOCUMENT = "android.provider.action.MANAGE_DOCUMENT";
119 
120     /** {@hide} */
121     public static final String
122             ACTION_BROWSE_DOCUMENT_ROOT = "android.provider.action.BROWSE_DOCUMENT_ROOT";
123 
124     /** {@hide} */
125     public static final String
126             ACTION_DOCUMENT_ROOT_SETTINGS = "android.provider.action.DOCUMENT_ROOT_SETTINGS";
127 
128     /**
129      * Buffer is large enough to rewind past any EXIF headers.
130      */
131     private static final int THUMBNAIL_BUFFER_SIZE = (int) (128 * KB_IN_BYTES);
132 
133     /**
134      * Constants related to a document, including {@link Cursor} column names
135      * and flags.
136      * <p>
137      * A document can be either an openable stream (with a specific MIME type),
138      * or a directory containing additional documents (with the
139      * {@link #MIME_TYPE_DIR} MIME type). A directory represents the top of a
140      * subtree containing zero or more documents, which can recursively contain
141      * even more documents and directories.
142      * <p>
143      * All columns are <em>read-only</em> to client applications.
144      */
145     public final static class Document {
Document()146         private Document() {
147         }
148 
149         /**
150          * Unique ID of a document. This ID is both provided by and interpreted
151          * by a {@link DocumentsProvider}, and should be treated as an opaque
152          * value by client applications. This column is required.
153          * <p>
154          * Each document must have a unique ID within a provider, but that
155          * single document may be included as a child of multiple directories.
156          * <p>
157          * A provider must always return durable IDs, since they will be used to
158          * issue long-term URI permission grants when an application interacts
159          * with {@link Intent#ACTION_OPEN_DOCUMENT} and
160          * {@link Intent#ACTION_CREATE_DOCUMENT}.
161          * <p>
162          * Type: STRING
163          */
164         public static final String COLUMN_DOCUMENT_ID = "document_id";
165 
166         /**
167          * Concrete MIME type of a document. For example, "image/png" or
168          * "application/pdf" for openable files. A document can also be a
169          * directory containing additional documents, which is represented with
170          * the {@link #MIME_TYPE_DIR} MIME type. This column is required.
171          * <p>
172          * Type: STRING
173          *
174          * @see #MIME_TYPE_DIR
175          */
176         public static final String COLUMN_MIME_TYPE = "mime_type";
177 
178         /**
179          * Display name of a document, used as the primary title displayed to a
180          * user. This column is required.
181          * <p>
182          * Type: STRING
183          */
184         public static final String COLUMN_DISPLAY_NAME = OpenableColumns.DISPLAY_NAME;
185 
186         /**
187          * Summary of a document, which may be shown to a user. This column is
188          * optional, and may be {@code null}.
189          * <p>
190          * Type: STRING
191          */
192         public static final String COLUMN_SUMMARY = "summary";
193 
194         /**
195          * Timestamp when a document was last modified, in milliseconds since
196          * January 1, 1970 00:00:00.0 UTC. This column is required, and may be
197          * {@code null} if unknown. A {@link DocumentsProvider} can update this
198          * field using events from {@link OnCloseListener} or other reliable
199          * {@link ParcelFileDescriptor} transports.
200          * <p>
201          * Type: INTEGER (long)
202          *
203          * @see System#currentTimeMillis()
204          */
205         public static final String COLUMN_LAST_MODIFIED = "last_modified";
206 
207         /**
208          * Specific icon resource ID for a document. This column is optional,
209          * and may be {@code null} to use a platform-provided default icon based
210          * on {@link #COLUMN_MIME_TYPE}.
211          * <p>
212          * Type: INTEGER (int)
213          */
214         public static final String COLUMN_ICON = "icon";
215 
216         /**
217          * Flags that apply to a document. This column is required.
218          * <p>
219          * Type: INTEGER (int)
220          *
221          * @see #FLAG_SUPPORTS_WRITE
222          * @see #FLAG_SUPPORTS_DELETE
223          * @see #FLAG_SUPPORTS_THUMBNAIL
224          * @see #FLAG_DIR_PREFERS_GRID
225          * @see #FLAG_DIR_PREFERS_LAST_MODIFIED
226          */
227         public static final String COLUMN_FLAGS = "flags";
228 
229         /**
230          * Size of a document, in bytes, or {@code null} if unknown. This column
231          * is required.
232          * <p>
233          * Type: INTEGER (long)
234          */
235         public static final String COLUMN_SIZE = OpenableColumns.SIZE;
236 
237         /**
238          * MIME type of a document which is a directory that may contain
239          * additional documents.
240          *
241          * @see #COLUMN_MIME_TYPE
242          */
243         public static final String MIME_TYPE_DIR = "vnd.android.document/directory";
244 
245         /**
246          * Flag indicating that a document can be represented as a thumbnail.
247          *
248          * @see #COLUMN_FLAGS
249          * @see DocumentsContract#getDocumentThumbnail(ContentResolver, Uri,
250          *      Point, CancellationSignal)
251          * @see DocumentsProvider#openDocumentThumbnail(String, Point,
252          *      android.os.CancellationSignal)
253          */
254         public static final int FLAG_SUPPORTS_THUMBNAIL = 1;
255 
256         /**
257          * Flag indicating that a document supports writing.
258          * <p>
259          * When a document is opened with {@link Intent#ACTION_OPEN_DOCUMENT},
260          * the calling application is granted both
261          * {@link Intent#FLAG_GRANT_READ_URI_PERMISSION} and
262          * {@link Intent#FLAG_GRANT_WRITE_URI_PERMISSION}. However, the actual
263          * writability of a document may change over time, for example due to
264          * remote access changes. This flag indicates that a document client can
265          * expect {@link ContentResolver#openOutputStream(Uri)} to succeed.
266          *
267          * @see #COLUMN_FLAGS
268          */
269         public static final int FLAG_SUPPORTS_WRITE = 1 << 1;
270 
271         /**
272          * Flag indicating that a document is deletable.
273          *
274          * @see #COLUMN_FLAGS
275          * @see DocumentsContract#deleteDocument(ContentResolver, Uri)
276          * @see DocumentsProvider#deleteDocument(String)
277          */
278         public static final int FLAG_SUPPORTS_DELETE = 1 << 2;
279 
280         /**
281          * Flag indicating that a document is a directory that supports creation
282          * of new files within it. Only valid when {@link #COLUMN_MIME_TYPE} is
283          * {@link #MIME_TYPE_DIR}.
284          *
285          * @see #COLUMN_FLAGS
286          * @see DocumentsProvider#createDocument(String, String, String)
287          */
288         public static final int FLAG_DIR_SUPPORTS_CREATE = 1 << 3;
289 
290         /**
291          * Flag indicating that a directory prefers its contents be shown in a
292          * larger format grid. Usually suitable when a directory contains mostly
293          * pictures. Only valid when {@link #COLUMN_MIME_TYPE} is
294          * {@link #MIME_TYPE_DIR}.
295          *
296          * @see #COLUMN_FLAGS
297          */
298         public static final int FLAG_DIR_PREFERS_GRID = 1 << 4;
299 
300         /**
301          * Flag indicating that a directory prefers its contents be sorted by
302          * {@link #COLUMN_LAST_MODIFIED}. Only valid when
303          * {@link #COLUMN_MIME_TYPE} is {@link #MIME_TYPE_DIR}.
304          *
305          * @see #COLUMN_FLAGS
306          */
307         public static final int FLAG_DIR_PREFERS_LAST_MODIFIED = 1 << 5;
308 
309         /**
310          * Flag indicating that a document can be renamed.
311          *
312          * @see #COLUMN_FLAGS
313          * @see DocumentsContract#renameDocument(ContentProviderClient, Uri,
314          *      String)
315          * @see DocumentsProvider#renameDocument(String, String)
316          */
317         public static final int FLAG_SUPPORTS_RENAME = 1 << 6;
318 
319         /**
320          * Flag indicating that document titles should be hidden when viewing
321          * this directory in a larger format grid. For example, a directory
322          * containing only images may want the image thumbnails to speak for
323          * themselves. Only valid when {@link #COLUMN_MIME_TYPE} is
324          * {@link #MIME_TYPE_DIR}.
325          *
326          * @see #COLUMN_FLAGS
327          * @see #FLAG_DIR_PREFERS_GRID
328          * @hide
329          */
330         public static final int FLAG_DIR_HIDE_GRID_TITLES = 1 << 16;
331     }
332 
333     /**
334      * Constants related to a root of documents, including {@link Cursor} column
335      * names and flags. A root is the start of a tree of documents, such as a
336      * physical storage device, or an account. Each root starts at the directory
337      * referenced by {@link Root#COLUMN_DOCUMENT_ID}, which can recursively
338      * contain both documents and directories.
339      * <p>
340      * All columns are <em>read-only</em> to client applications.
341      */
342     public final static class Root {
Root()343         private Root() {
344         }
345 
346         /**
347          * Unique ID of a root. This ID is both provided by and interpreted by a
348          * {@link DocumentsProvider}, and should be treated as an opaque value
349          * by client applications. This column is required.
350          * <p>
351          * Type: STRING
352          */
353         public static final String COLUMN_ROOT_ID = "root_id";
354 
355         /**
356          * Flags that apply to a root. This column is required.
357          * <p>
358          * Type: INTEGER (int)
359          *
360          * @see #FLAG_LOCAL_ONLY
361          * @see #FLAG_SUPPORTS_CREATE
362          * @see #FLAG_SUPPORTS_RECENTS
363          * @see #FLAG_SUPPORTS_SEARCH
364          */
365         public static final String COLUMN_FLAGS = "flags";
366 
367         /**
368          * Icon resource ID for a root. This column is required.
369          * <p>
370          * Type: INTEGER (int)
371          */
372         public static final String COLUMN_ICON = "icon";
373 
374         /**
375          * Title for a root, which will be shown to a user. This column is
376          * required. For a single storage service surfacing multiple accounts as
377          * different roots, this title should be the name of the service.
378          * <p>
379          * Type: STRING
380          */
381         public static final String COLUMN_TITLE = "title";
382 
383         /**
384          * Summary for this root, which may be shown to a user. This column is
385          * optional, and may be {@code null}. For a single storage service
386          * surfacing multiple accounts as different roots, this summary should
387          * be the name of the account.
388          * <p>
389          * Type: STRING
390          */
391         public static final String COLUMN_SUMMARY = "summary";
392 
393         /**
394          * Document which is a directory that represents the top directory of
395          * this root. This column is required.
396          * <p>
397          * Type: STRING
398          *
399          * @see Document#COLUMN_DOCUMENT_ID
400          */
401         public static final String COLUMN_DOCUMENT_ID = "document_id";
402 
403         /**
404          * Number of bytes available in this root. This column is optional, and
405          * may be {@code null} if unknown or unbounded.
406          * <p>
407          * Type: INTEGER (long)
408          */
409         public static final String COLUMN_AVAILABLE_BYTES = "available_bytes";
410 
411         /**
412          * MIME types supported by this root. This column is optional, and if
413          * {@code null} the root is assumed to support all MIME types. Multiple
414          * MIME types can be separated by a newline. For example, a root
415          * supporting audio might return "audio/*\napplication/x-flac".
416          * <p>
417          * Type: STRING
418          */
419         public static final String COLUMN_MIME_TYPES = "mime_types";
420 
421         /** {@hide} */
422         public static final String MIME_TYPE_ITEM = "vnd.android.document/root";
423 
424         /**
425          * Flag indicating that at least one directory under this root supports
426          * creating content. Roots with this flag will be shown when an
427          * application interacts with {@link Intent#ACTION_CREATE_DOCUMENT}.
428          *
429          * @see #COLUMN_FLAGS
430          */
431         public static final int FLAG_SUPPORTS_CREATE = 1;
432 
433         /**
434          * Flag indicating that this root offers content that is strictly local
435          * on the device. That is, no network requests are made for the content.
436          *
437          * @see #COLUMN_FLAGS
438          * @see Intent#EXTRA_LOCAL_ONLY
439          */
440         public static final int FLAG_LOCAL_ONLY = 1 << 1;
441 
442         /**
443          * Flag indicating that this root can be queried to provide recently
444          * modified documents.
445          *
446          * @see #COLUMN_FLAGS
447          * @see DocumentsContract#buildRecentDocumentsUri(String, String)
448          * @see DocumentsProvider#queryRecentDocuments(String, String[])
449          */
450         public static final int FLAG_SUPPORTS_RECENTS = 1 << 2;
451 
452         /**
453          * Flag indicating that this root supports search.
454          *
455          * @see #COLUMN_FLAGS
456          * @see DocumentsContract#buildSearchDocumentsUri(String, String,
457          *      String)
458          * @see DocumentsProvider#querySearchDocuments(String, String,
459          *      String[])
460          */
461         public static final int FLAG_SUPPORTS_SEARCH = 1 << 3;
462 
463         /**
464          * Flag indicating that this root supports testing parent child
465          * relationships.
466          *
467          * @see #COLUMN_FLAGS
468          * @see DocumentsProvider#isChildDocument(String, String)
469          */
470         public static final int FLAG_SUPPORTS_IS_CHILD = 1 << 4;
471 
472         /**
473          * Flag indicating that this root is currently empty. This may be used
474          * to hide the root when opening documents, but the root will still be
475          * shown when creating documents and {@link #FLAG_SUPPORTS_CREATE} is
476          * also set. If the value of this flag changes, such as when a root
477          * becomes non-empty, you must send a content changed notification for
478          * {@link DocumentsContract#buildRootsUri(String)}.
479          *
480          * @see #COLUMN_FLAGS
481          * @see ContentResolver#notifyChange(Uri,
482          *      android.database.ContentObserver, boolean)
483          * @hide
484          */
485         public static final int FLAG_EMPTY = 1 << 16;
486 
487         /**
488          * Flag indicating that this root should only be visible to advanced
489          * users.
490          *
491          * @see #COLUMN_FLAGS
492          * @hide
493          */
494         public static final int FLAG_ADVANCED = 1 << 17;
495 
496         /**
497          * Flag indicating that this root has settings.
498          *
499          * @see #COLUMN_FLAGS
500          * @see DocumentsContract#ACTION_DOCUMENT_ROOT_SETTINGS
501          * @hide
502          */
503         public static final int FLAG_HAS_SETTINGS = 1 << 18;
504     }
505 
506     /**
507      * Optional boolean flag included in a directory {@link Cursor#getExtras()}
508      * indicating that a document provider is still loading data. For example, a
509      * provider has returned some results, but is still waiting on an
510      * outstanding network request. The provider must send a content changed
511      * notification when loading is finished.
512      *
513      * @see ContentResolver#notifyChange(Uri, android.database.ContentObserver,
514      *      boolean)
515      */
516     public static final String EXTRA_LOADING = "loading";
517 
518     /**
519      * Optional string included in a directory {@link Cursor#getExtras()}
520      * providing an informational message that should be shown to a user. For
521      * example, a provider may wish to indicate that not all documents are
522      * available.
523      */
524     public static final String EXTRA_INFO = "info";
525 
526     /**
527      * Optional string included in a directory {@link Cursor#getExtras()}
528      * providing an error message that should be shown to a user. For example, a
529      * provider may wish to indicate that a network error occurred. The user may
530      * choose to retry, resulting in a new query.
531      */
532     public static final String EXTRA_ERROR = "error";
533 
534     /** {@hide} */
535     public static final String METHOD_CREATE_DOCUMENT = "android:createDocument";
536     /** {@hide} */
537     public static final String METHOD_RENAME_DOCUMENT = "android:renameDocument";
538     /** {@hide} */
539     public static final String METHOD_DELETE_DOCUMENT = "android:deleteDocument";
540 
541     /** {@hide} */
542     public static final String EXTRA_URI = "uri";
543 
544     private static final String PATH_ROOT = "root";
545     private static final String PATH_RECENT = "recent";
546     private static final String PATH_DOCUMENT = "document";
547     private static final String PATH_CHILDREN = "children";
548     private static final String PATH_SEARCH = "search";
549     private static final String PATH_TREE = "tree";
550 
551     private static final String PARAM_QUERY = "query";
552     private static final String PARAM_MANAGE = "manage";
553 
554     /**
555      * Build URI representing the roots of a document provider. When queried, a
556      * provider will return one or more rows with columns defined by
557      * {@link Root}.
558      *
559      * @see DocumentsProvider#queryRoots(String[])
560      */
buildRootsUri(String authority)561     public static Uri buildRootsUri(String authority) {
562         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
563                 .authority(authority).appendPath(PATH_ROOT).build();
564     }
565 
566     /**
567      * Build URI representing the given {@link Root#COLUMN_ROOT_ID} in a
568      * document provider.
569      *
570      * @see #getRootId(Uri)
571      */
buildRootUri(String authority, String rootId)572     public static Uri buildRootUri(String authority, String rootId) {
573         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
574                 .authority(authority).appendPath(PATH_ROOT).appendPath(rootId).build();
575     }
576 
577     /**
578      * Build URI representing the recently modified documents of a specific root
579      * in a document provider. When queried, a provider will return zero or more
580      * rows with columns defined by {@link Document}.
581      *
582      * @see DocumentsProvider#queryRecentDocuments(String, String[])
583      * @see #getRootId(Uri)
584      */
buildRecentDocumentsUri(String authority, String rootId)585     public static Uri buildRecentDocumentsUri(String authority, String rootId) {
586         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
587                 .authority(authority).appendPath(PATH_ROOT).appendPath(rootId)
588                 .appendPath(PATH_RECENT).build();
589     }
590 
591     /**
592      * Build URI representing access to descendant documents of the given
593      * {@link Document#COLUMN_DOCUMENT_ID}.
594      *
595      * @see #getTreeDocumentId(Uri)
596      */
buildTreeDocumentUri(String authority, String documentId)597     public static Uri buildTreeDocumentUri(String authority, String documentId) {
598         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(authority)
599                 .appendPath(PATH_TREE).appendPath(documentId).build();
600     }
601 
602     /**
603      * Build URI representing the target {@link Document#COLUMN_DOCUMENT_ID} in
604      * a document provider. When queried, a provider will return a single row
605      * with columns defined by {@link Document}.
606      *
607      * @see DocumentsProvider#queryDocument(String, String[])
608      * @see #getDocumentId(Uri)
609      */
buildDocumentUri(String authority, String documentId)610     public static Uri buildDocumentUri(String authority, String documentId) {
611         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
612                 .authority(authority).appendPath(PATH_DOCUMENT).appendPath(documentId).build();
613     }
614 
615     /**
616      * Build URI representing the target {@link Document#COLUMN_DOCUMENT_ID} in
617      * a document provider. When queried, a provider will return a single row
618      * with columns defined by {@link Document}.
619      * <p>
620      * However, instead of directly accessing the target document, the returned
621      * URI will leverage access granted through a subtree URI, typically
622      * returned by {@link Intent#ACTION_OPEN_DOCUMENT_TREE}. The target document
623      * must be a descendant (child, grandchild, etc) of the subtree.
624      * <p>
625      * This is typically used to access documents under a user-selected
626      * directory tree, since it doesn't require the user to separately confirm
627      * each new document access.
628      *
629      * @param treeUri the subtree to leverage to gain access to the target
630      *            document. The target directory must be a descendant of this
631      *            subtree.
632      * @param documentId the target document, which the caller may not have
633      *            direct access to.
634      * @see Intent#ACTION_OPEN_DOCUMENT_TREE
635      * @see DocumentsProvider#isChildDocument(String, String)
636      * @see #buildDocumentUri(String, String)
637      */
buildDocumentUriUsingTree(Uri treeUri, String documentId)638     public static Uri buildDocumentUriUsingTree(Uri treeUri, String documentId) {
639         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
640                 .authority(treeUri.getAuthority()).appendPath(PATH_TREE)
641                 .appendPath(getTreeDocumentId(treeUri)).appendPath(PATH_DOCUMENT)
642                 .appendPath(documentId).build();
643     }
644 
645     /** {@hide} */
buildDocumentUriMaybeUsingTree(Uri baseUri, String documentId)646     public static Uri buildDocumentUriMaybeUsingTree(Uri baseUri, String documentId) {
647         if (isTreeUri(baseUri)) {
648             return buildDocumentUriUsingTree(baseUri, documentId);
649         } else {
650             return buildDocumentUri(baseUri.getAuthority(), documentId);
651         }
652     }
653 
654     /**
655      * Build URI representing the children of the target directory in a document
656      * provider. When queried, a provider will return zero or more rows with
657      * columns defined by {@link Document}.
658      *
659      * @param parentDocumentId the document to return children for, which must
660      *            be a directory with MIME type of
661      *            {@link Document#MIME_TYPE_DIR}.
662      * @see DocumentsProvider#queryChildDocuments(String, String[], String)
663      * @see #getDocumentId(Uri)
664      */
buildChildDocumentsUri(String authority, String parentDocumentId)665     public static Uri buildChildDocumentsUri(String authority, String parentDocumentId) {
666         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(authority)
667                 .appendPath(PATH_DOCUMENT).appendPath(parentDocumentId).appendPath(PATH_CHILDREN)
668                 .build();
669     }
670 
671     /**
672      * Build URI representing the children of the target directory in a document
673      * provider. When queried, a provider will return zero or more rows with
674      * columns defined by {@link Document}.
675      * <p>
676      * However, instead of directly accessing the target directory, the returned
677      * URI will leverage access granted through a subtree URI, typically
678      * returned by {@link Intent#ACTION_OPEN_DOCUMENT_TREE}. The target
679      * directory must be a descendant (child, grandchild, etc) of the subtree.
680      * <p>
681      * This is typically used to access documents under a user-selected
682      * directory tree, since it doesn't require the user to separately confirm
683      * each new document access.
684      *
685      * @param treeUri the subtree to leverage to gain access to the target
686      *            document. The target directory must be a descendant of this
687      *            subtree.
688      * @param parentDocumentId the document to return children for, which the
689      *            caller may not have direct access to, and which must be a
690      *            directory with MIME type of {@link Document#MIME_TYPE_DIR}.
691      * @see Intent#ACTION_OPEN_DOCUMENT_TREE
692      * @see DocumentsProvider#isChildDocument(String, String)
693      * @see #buildChildDocumentsUri(String, String)
694      */
buildChildDocumentsUriUsingTree(Uri treeUri, String parentDocumentId)695     public static Uri buildChildDocumentsUriUsingTree(Uri treeUri, String parentDocumentId) {
696         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT)
697                 .authority(treeUri.getAuthority()).appendPath(PATH_TREE)
698                 .appendPath(getTreeDocumentId(treeUri)).appendPath(PATH_DOCUMENT)
699                 .appendPath(parentDocumentId).appendPath(PATH_CHILDREN).build();
700     }
701 
702     /**
703      * Build URI representing a search for matching documents under a specific
704      * root in a document provider. When queried, a provider will return zero or
705      * more rows with columns defined by {@link Document}.
706      *
707      * @see DocumentsProvider#querySearchDocuments(String, String, String[])
708      * @see #getRootId(Uri)
709      * @see #getSearchDocumentsQuery(Uri)
710      */
buildSearchDocumentsUri( String authority, String rootId, String query)711     public static Uri buildSearchDocumentsUri(
712             String authority, String rootId, String query) {
713         return new Uri.Builder().scheme(ContentResolver.SCHEME_CONTENT).authority(authority)
714                 .appendPath(PATH_ROOT).appendPath(rootId).appendPath(PATH_SEARCH)
715                 .appendQueryParameter(PARAM_QUERY, query).build();
716     }
717 
718     /**
719      * Test if the given URI represents a {@link Document} backed by a
720      * {@link DocumentsProvider}.
721      *
722      * @see #buildDocumentUri(String, String)
723      * @see #buildDocumentUriUsingTree(Uri, String)
724      */
isDocumentUri(Context context, Uri uri)725     public static boolean isDocumentUri(Context context, Uri uri) {
726         final List<String> paths = uri.getPathSegments();
727         if (paths.size() == 2 && PATH_DOCUMENT.equals(paths.get(0))) {
728             return isDocumentsProvider(context, uri.getAuthority());
729         }
730         if (paths.size() == 4 && PATH_TREE.equals(paths.get(0))
731                 && PATH_DOCUMENT.equals(paths.get(2))) {
732             return isDocumentsProvider(context, uri.getAuthority());
733         }
734         return false;
735     }
736 
737     /** {@hide} */
isTreeUri(Uri uri)738     public static boolean isTreeUri(Uri uri) {
739         final List<String> paths = uri.getPathSegments();
740         return (paths.size() >= 2 && PATH_TREE.equals(paths.get(0)));
741     }
742 
isDocumentsProvider(Context context, String authority)743     private static boolean isDocumentsProvider(Context context, String authority) {
744         final Intent intent = new Intent(PROVIDER_INTERFACE);
745         final List<ResolveInfo> infos = context.getPackageManager()
746                 .queryIntentContentProviders(intent, 0);
747         for (ResolveInfo info : infos) {
748             if (authority.equals(info.providerInfo.authority)) {
749                 return true;
750             }
751         }
752         return false;
753     }
754 
755     /**
756      * Extract the {@link Root#COLUMN_ROOT_ID} from the given URI.
757      */
getRootId(Uri rootUri)758     public static String getRootId(Uri rootUri) {
759         final List<String> paths = rootUri.getPathSegments();
760         if (paths.size() >= 2 && PATH_ROOT.equals(paths.get(0))) {
761             return paths.get(1);
762         }
763         throw new IllegalArgumentException("Invalid URI: " + rootUri);
764     }
765 
766     /**
767      * Extract the {@link Document#COLUMN_DOCUMENT_ID} from the given URI.
768      *
769      * @see #isDocumentUri(Context, Uri)
770      */
getDocumentId(Uri documentUri)771     public static String getDocumentId(Uri documentUri) {
772         final List<String> paths = documentUri.getPathSegments();
773         if (paths.size() >= 2 && PATH_DOCUMENT.equals(paths.get(0))) {
774             return paths.get(1);
775         }
776         if (paths.size() >= 4 && PATH_TREE.equals(paths.get(0))
777                 && PATH_DOCUMENT.equals(paths.get(2))) {
778             return paths.get(3);
779         }
780         throw new IllegalArgumentException("Invalid URI: " + documentUri);
781     }
782 
783     /**
784      * Extract the via {@link Document#COLUMN_DOCUMENT_ID} from the given URI.
785      */
getTreeDocumentId(Uri documentUri)786     public static String getTreeDocumentId(Uri documentUri) {
787         final List<String> paths = documentUri.getPathSegments();
788         if (paths.size() >= 2 && PATH_TREE.equals(paths.get(0))) {
789             return paths.get(1);
790         }
791         throw new IllegalArgumentException("Invalid URI: " + documentUri);
792     }
793 
794     /**
795      * Extract the search query from a URI built by
796      * {@link #buildSearchDocumentsUri(String, String, String)}.
797      */
getSearchDocumentsQuery(Uri searchDocumentsUri)798     public static String getSearchDocumentsQuery(Uri searchDocumentsUri) {
799         return searchDocumentsUri.getQueryParameter(PARAM_QUERY);
800     }
801 
802     /** {@hide} */
setManageMode(Uri uri)803     public static Uri setManageMode(Uri uri) {
804         return uri.buildUpon().appendQueryParameter(PARAM_MANAGE, "true").build();
805     }
806 
807     /** {@hide} */
isManageMode(Uri uri)808     public static boolean isManageMode(Uri uri) {
809         return uri.getBooleanQueryParameter(PARAM_MANAGE, false);
810     }
811 
812     /**
813      * Return thumbnail representing the document at the given URI. Callers are
814      * responsible for their own in-memory caching.
815      *
816      * @param documentUri document to return thumbnail for, which must have
817      *            {@link Document#FLAG_SUPPORTS_THUMBNAIL} set.
818      * @param size optimal thumbnail size desired. A provider may return a
819      *            thumbnail of a different size, but never more than double the
820      *            requested size.
821      * @param signal signal used to indicate if caller is no longer interested
822      *            in the thumbnail.
823      * @return decoded thumbnail, or {@code null} if problem was encountered.
824      * @see DocumentsProvider#openDocumentThumbnail(String, Point,
825      *      android.os.CancellationSignal)
826      */
getDocumentThumbnail( ContentResolver resolver, Uri documentUri, Point size, CancellationSignal signal)827     public static Bitmap getDocumentThumbnail(
828             ContentResolver resolver, Uri documentUri, Point size, CancellationSignal signal) {
829         final ContentProviderClient client = resolver.acquireUnstableContentProviderClient(
830                 documentUri.getAuthority());
831         try {
832             return getDocumentThumbnail(client, documentUri, size, signal);
833         } catch (Exception e) {
834             if (!(e instanceof OperationCanceledException)) {
835                 Log.w(TAG, "Failed to load thumbnail for " + documentUri + ": " + e);
836             }
837             return null;
838         } finally {
839             ContentProviderClient.releaseQuietly(client);
840         }
841     }
842 
843     /** {@hide} */
getDocumentThumbnail( ContentProviderClient client, Uri documentUri, Point size, CancellationSignal signal)844     public static Bitmap getDocumentThumbnail(
845             ContentProviderClient client, Uri documentUri, Point size, CancellationSignal signal)
846             throws RemoteException, IOException {
847         final Bundle openOpts = new Bundle();
848         openOpts.putParcelable(ContentResolver.EXTRA_SIZE, size);
849 
850         AssetFileDescriptor afd = null;
851         Bitmap bitmap = null;
852         try {
853             afd = client.openTypedAssetFileDescriptor(documentUri, "image/*", openOpts, signal);
854 
855             final FileDescriptor fd = afd.getFileDescriptor();
856             final long offset = afd.getStartOffset();
857 
858             // Try seeking on the returned FD, since it gives us the most
859             // optimal decode path; otherwise fall back to buffering.
860             BufferedInputStream is = null;
861             try {
862                 Os.lseek(fd, offset, SEEK_SET);
863             } catch (ErrnoException e) {
864                 is = new BufferedInputStream(new FileInputStream(fd), THUMBNAIL_BUFFER_SIZE);
865                 is.mark(THUMBNAIL_BUFFER_SIZE);
866             }
867 
868             // We requested a rough thumbnail size, but the remote size may have
869             // returned something giant, so defensively scale down as needed.
870             final BitmapFactory.Options opts = new BitmapFactory.Options();
871             opts.inJustDecodeBounds = true;
872             if (is != null) {
873                 BitmapFactory.decodeStream(is, null, opts);
874             } else {
875                 BitmapFactory.decodeFileDescriptor(fd, null, opts);
876             }
877 
878             final int widthSample = opts.outWidth / size.x;
879             final int heightSample = opts.outHeight / size.y;
880 
881             opts.inJustDecodeBounds = false;
882             opts.inSampleSize = Math.min(widthSample, heightSample);
883             if (is != null) {
884                 is.reset();
885                 bitmap = BitmapFactory.decodeStream(is, null, opts);
886             } else {
887                 try {
888                     Os.lseek(fd, offset, SEEK_SET);
889                 } catch (ErrnoException e) {
890                     e.rethrowAsIOException();
891                 }
892                 bitmap = BitmapFactory.decodeFileDescriptor(fd, null, opts);
893             }
894 
895             // Transform the bitmap if requested. We use a side-channel to
896             // communicate the orientation, since EXIF thumbnails don't contain
897             // the rotation flags of the original image.
898             final Bundle extras = afd.getExtras();
899             final int orientation = (extras != null) ? extras.getInt(EXTRA_ORIENTATION, 0) : 0;
900             if (orientation != 0) {
901                 final int width = bitmap.getWidth();
902                 final int height = bitmap.getHeight();
903 
904                 final Matrix m = new Matrix();
905                 m.setRotate(orientation, width / 2, height / 2);
906                 bitmap = Bitmap.createBitmap(bitmap, 0, 0, width, height, m, false);
907             }
908         } finally {
909             IoUtils.closeQuietly(afd);
910         }
911 
912         return bitmap;
913     }
914 
915     /**
916      * Create a new document with given MIME type and display name.
917      *
918      * @param parentDocumentUri directory with
919      *            {@link Document#FLAG_DIR_SUPPORTS_CREATE}
920      * @param mimeType MIME type of new document
921      * @param displayName name of new document
922      * @return newly created document, or {@code null} if failed
923      */
createDocument(ContentResolver resolver, Uri parentDocumentUri, String mimeType, String displayName)924     public static Uri createDocument(ContentResolver resolver, Uri parentDocumentUri,
925             String mimeType, String displayName) {
926         final ContentProviderClient client = resolver.acquireUnstableContentProviderClient(
927                 parentDocumentUri.getAuthority());
928         try {
929             return createDocument(client, parentDocumentUri, mimeType, displayName);
930         } catch (Exception e) {
931             Log.w(TAG, "Failed to create document", e);
932             return null;
933         } finally {
934             ContentProviderClient.releaseQuietly(client);
935         }
936     }
937 
938     /** {@hide} */
createDocument(ContentProviderClient client, Uri parentDocumentUri, String mimeType, String displayName)939     public static Uri createDocument(ContentProviderClient client, Uri parentDocumentUri,
940             String mimeType, String displayName) throws RemoteException {
941         final Bundle in = new Bundle();
942         in.putParcelable(DocumentsContract.EXTRA_URI, parentDocumentUri);
943         in.putString(Document.COLUMN_MIME_TYPE, mimeType);
944         in.putString(Document.COLUMN_DISPLAY_NAME, displayName);
945 
946         final Bundle out = client.call(METHOD_CREATE_DOCUMENT, null, in);
947         return out.getParcelable(DocumentsContract.EXTRA_URI);
948     }
949 
950     /**
951      * Change the display name of an existing document.
952      * <p>
953      * If the underlying provider needs to create a new
954      * {@link Document#COLUMN_DOCUMENT_ID} to represent the updated display
955      * name, that new document is returned and the original document is no
956      * longer valid. Otherwise, the original document is returned.
957      *
958      * @param documentUri document with {@link Document#FLAG_SUPPORTS_RENAME}
959      * @param displayName updated name for document
960      * @return the existing or new document after the rename, or {@code null} if
961      *         failed.
962      */
renameDocument(ContentResolver resolver, Uri documentUri, String displayName)963     public static Uri renameDocument(ContentResolver resolver, Uri documentUri,
964             String displayName) {
965         final ContentProviderClient client = resolver.acquireUnstableContentProviderClient(
966                 documentUri.getAuthority());
967         try {
968             return renameDocument(client, documentUri, displayName);
969         } catch (Exception e) {
970             Log.w(TAG, "Failed to rename document", e);
971             return null;
972         } finally {
973             ContentProviderClient.releaseQuietly(client);
974         }
975     }
976 
977     /** {@hide} */
renameDocument(ContentProviderClient client, Uri documentUri, String displayName)978     public static Uri renameDocument(ContentProviderClient client, Uri documentUri,
979             String displayName) throws RemoteException {
980         final Bundle in = new Bundle();
981         in.putParcelable(DocumentsContract.EXTRA_URI, documentUri);
982         in.putString(Document.COLUMN_DISPLAY_NAME, displayName);
983 
984         final Bundle out = client.call(METHOD_RENAME_DOCUMENT, null, in);
985         final Uri outUri = out.getParcelable(DocumentsContract.EXTRA_URI);
986         return (outUri != null) ? outUri : documentUri;
987     }
988 
989     /**
990      * Delete the given document.
991      *
992      * @param documentUri document with {@link Document#FLAG_SUPPORTS_DELETE}
993      * @return if the document was deleted successfully.
994      */
deleteDocument(ContentResolver resolver, Uri documentUri)995     public static boolean deleteDocument(ContentResolver resolver, Uri documentUri) {
996         final ContentProviderClient client = resolver.acquireUnstableContentProviderClient(
997                 documentUri.getAuthority());
998         try {
999             deleteDocument(client, documentUri);
1000             return true;
1001         } catch (Exception e) {
1002             Log.w(TAG, "Failed to delete document", e);
1003             return false;
1004         } finally {
1005             ContentProviderClient.releaseQuietly(client);
1006         }
1007     }
1008 
1009     /** {@hide} */
deleteDocument(ContentProviderClient client, Uri documentUri)1010     public static void deleteDocument(ContentProviderClient client, Uri documentUri)
1011             throws RemoteException {
1012         final Bundle in = new Bundle();
1013         in.putParcelable(DocumentsContract.EXTRA_URI, documentUri);
1014 
1015         client.call(METHOD_DELETE_DOCUMENT, null, in);
1016     }
1017 
1018     /**
1019      * Open the given image for thumbnail purposes, using any embedded EXIF
1020      * thumbnail if available, and providing orientation hints from the parent
1021      * image.
1022      *
1023      * @hide
1024      */
openImageThumbnail(File file)1025     public static AssetFileDescriptor openImageThumbnail(File file) throws FileNotFoundException {
1026         final ParcelFileDescriptor pfd = ParcelFileDescriptor.open(
1027                 file, ParcelFileDescriptor.MODE_READ_ONLY);
1028         Bundle extras = null;
1029 
1030         try {
1031             final ExifInterface exif = new ExifInterface(file.getAbsolutePath());
1032 
1033             switch (exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, -1)) {
1034                 case ExifInterface.ORIENTATION_ROTATE_90:
1035                     extras = new Bundle(1);
1036                     extras.putInt(EXTRA_ORIENTATION, 90);
1037                     break;
1038                 case ExifInterface.ORIENTATION_ROTATE_180:
1039                     extras = new Bundle(1);
1040                     extras.putInt(EXTRA_ORIENTATION, 180);
1041                     break;
1042                 case ExifInterface.ORIENTATION_ROTATE_270:
1043                     extras = new Bundle(1);
1044                     extras.putInt(EXTRA_ORIENTATION, 270);
1045                     break;
1046             }
1047 
1048             final long[] thumb = exif.getThumbnailRange();
1049             if (thumb != null) {
1050                 return new AssetFileDescriptor(pfd, thumb[0], thumb[1], extras);
1051             }
1052         } catch (IOException e) {
1053         }
1054 
1055         return new AssetFileDescriptor(pfd, 0, AssetFileDescriptor.UNKNOWN_LENGTH, extras);
1056     }
1057 }
1058