src/com/android/documentsui/archives/Archive.java - platform/packages/apps/DocumentsUI - Gitiles

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.documentsui.archives;

 import android.content.Context;
 import android.content.res.AssetFileDescriptor;
 import android.database.Cursor;
 import android.database.MatrixCursor;
 import android.graphics.Point;
 import android.net.Uri;
 import android.os.CancellationSignal;
 import android.os.ParcelFileDescriptor;
 import android.provider.DocumentsContract.Document;
 import android.provider.MetadataReader;
 import android.system.ErrnoException;
 import android.system.Os;
 import android.system.OsConstants;
 import android.text.TextUtils;
 import android.webkit.MimeTypeMap;

 import androidx.annotation.GuardedBy;
 import androidx.annotation.Nullable;
 import androidx.core.util.Preconditions;

 import java.io.Closeable;
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;

 import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;

 /**
  * Provides basic implementation for creating, extracting and accessing
  * files within archives exposed by a document provider.
  *
  * <p>This class is thread safe.
  */
 public abstract class Archive implements Closeable {
     private static final String TAG = "Archive";

     public static final String[] DEFAULT_PROJECTION = new String[] {
             Document.COLUMN_DOCUMENT_ID,
             Document.COLUMN_DISPLAY_NAME,
             Document.COLUMN_MIME_TYPE,
             Document.COLUMN_SIZE,
             Document.COLUMN_FLAGS
     };

     final Context mContext;
     final Uri mArchiveUri;
     final int mAccessMode;
     final Uri mNotificationUri;

     // The container as well as values are guarded by mEntries.
     @GuardedBy("mEntries")
     final Map<String, ZipArchiveEntry> mEntries;

     // The container as well as values and elements of values are guarded by mEntries.
     @GuardedBy("mEntries")
     final Map<String, List<ZipArchiveEntry>> mTree;

     Archive(
             Context context,
             Uri archiveUri,
             int accessMode,
             @Nullable Uri notificationUri) {
         mContext = context;
         mArchiveUri = archiveUri;
         mAccessMode = accessMode;
         mNotificationUri = notificationUri;

         mTree = new HashMap<>();
         mEntries = new HashMap<>();
     }

     /**
      * Returns a valid, normalized path for an entry.
      */
     public static String getEntryPath(ZipArchiveEntry entry) {
         Preconditions.checkArgument(entry.isDirectory() == entry.getName().endsWith("/"),
                 "Ill-formated ZIP-file.");
         if (entry.getName().startsWith("/")) {
             return entry.getName();
         } else {
             return "/" + entry.getName();
         }
     }

     /**
      * Returns true if the file descriptor is seekable.
      * @param descriptor File descriptor to check.
      */
     public static boolean canSeek(ParcelFileDescriptor descriptor) {
         try {
             return Os.lseek(descriptor.getFileDescriptor(), 0,
                     OsConstants.SEEK_CUR) == 0;
         } catch (ErrnoException e) {
             return false;
         }
     }

     /**
      * Lists child documents of an archive or a directory within an
      * archive. Must be called only for archives with supported mime type,
      * or for documents within archives.
      *
      * @see DocumentsProvider.queryChildDocuments(String, String[], String)
      */
     public Cursor queryChildDocuments(String documentId, @Nullable String[] projection,
             @Nullable String sortOrder) throws FileNotFoundException {
         final ArchiveId parsedParentId = ArchiveId.fromDocumentId(documentId);
         MorePreconditions.checkArgumentEquals(mArchiveUri, parsedParentId.mArchiveUri,
                 "Mismatching archive Uri. Expected: %s, actual: %s.");

         final MatrixCursor result = new MatrixCursor(
                 projection != null ? projection : DEFAULT_PROJECTION);
         if (mNotificationUri != null) {
             result.setNotificationUri(mContext.getContentResolver(), mNotificationUri);
         }

         synchronized (mEntries) {
             final List<ZipArchiveEntry> parentList = mTree.get(parsedParentId.mPath);
             if (parentList == null) {
                 throw new FileNotFoundException();
             }
             for (final ZipArchiveEntry entry : parentList) {
                 addCursorRow(result, entry);
             }
         }
         return result;
     }

     /**
      * Returns a MIME type of a document within an archive.
      *
      * @see DocumentsProvider.getDocumentType(String)
      */
     public String getDocumentType(String documentId) throws FileNotFoundException {
         final ArchiveId parsedId = ArchiveId.fromDocumentId(documentId);
         MorePreconditions.checkArgumentEquals(mArchiveUri, parsedId.mArchiveUri,
                 "Mismatching archive Uri. Expected: %s, actual: %s.");

         synchronized (mEntries) {
             final ZipArchiveEntry entry = mEntries.get(parsedId.mPath);
             if (entry == null) {
                 throw new FileNotFoundException();
             }
             return getMimeTypeForEntry(entry);
         }
     }

     /**
      * Returns true if a document within an archive is a child or any descendant of the archive
      * document or another document within the archive.
      *
      * @see DocumentsProvider.isChildDocument(String, String)
      */
     public boolean isChildDocument(String parentDocumentId, String documentId) {
         final ArchiveId parsedParentId = ArchiveId.fromDocumentId(parentDocumentId);
         final ArchiveId parsedId = ArchiveId.fromDocumentId(documentId);
         MorePreconditions.checkArgumentEquals(mArchiveUri, parsedParentId.mArchiveUri,
                 "Mismatching archive Uri. Expected: %s, actual: %s.");

         synchronized (mEntries) {
             final ZipArchiveEntry entry = mEntries.get(parsedId.mPath);
             if (entry == null) {
                 return false;
             }

             final ZipArchiveEntry parentEntry = mEntries.get(parsedParentId.mPath);
             if (parentEntry == null || !parentEntry.isDirectory()) {
                 return false;
             }

             // Add a trailing slash even if it's not a directory, so it's easy to check if the
             // entry is a descendant.
             String pathWithSlash = entry.isDirectory() ? getEntryPath(entry)
                     : getEntryPath(entry) + "/";

             return pathWithSlash.startsWith(parsedParentId.mPath) &&
                     !parsedParentId.mPath.equals(pathWithSlash);
         }
     }

     /**
      * Returns metadata of a document within an archive.
      *
      * @see DocumentsProvider.queryDocument(String, String[])
      */
     public Cursor queryDocument(String documentId, @Nullable String[] projection)
             throws FileNotFoundException {
         final ArchiveId parsedId = ArchiveId.fromDocumentId(documentId);
         MorePreconditions.checkArgumentEquals(mArchiveUri, parsedId.mArchiveUri,
                 "Mismatching archive Uri. Expected: %s, actual: %s.");

         synchronized (mEntries) {
             final ZipArchiveEntry entry = mEntries.get(parsedId.mPath);
             if (entry == null) {
                 throw new FileNotFoundException();
             }

             final MatrixCursor result = new MatrixCursor(
                     projection != null ? projection : DEFAULT_PROJECTION);
             if (mNotificationUri != null) {
                 result.setNotificationUri(mContext.getContentResolver(), mNotificationUri);
             }
             addCursorRow(result, entry);
             return result;
         }
     }

     /**
      * Creates a file within an archive.
      *
      * @see DocumentsProvider.createDocument(String, String, String))
      */
     public String createDocument(String parentDocumentId, String mimeType, String displayName)
             throws FileNotFoundException {
         throw new UnsupportedOperationException("Creating documents not supported.");
     }

     /**
      * Opens a file within an archive.
      *
      * @see DocumentsProvider.openDocument(String, String, CancellationSignal))
      */
     public ParcelFileDescriptor openDocument(
             String documentId, String mode, @Nullable final CancellationSignal signal)
             throws FileNotFoundException {
         throw new UnsupportedOperationException("Opening not supported.");
     }

     /**
      * Opens a thumbnail of a file within an archive.
      *
      * @see DocumentsProvider.openDocumentThumbnail(String, Point, CancellationSignal))
      */
     public AssetFileDescriptor openDocumentThumbnail(
             String documentId, Point sizeHint, final CancellationSignal signal)
             throws FileNotFoundException {
         throw new UnsupportedOperationException("Thumbnails not supported.");
     }

     /**
      * Creates an archive id for the passed path.
      */
     public ArchiveId createArchiveId(String path) {
         return new ArchiveId(mArchiveUri, mAccessMode, path);
     }

     /**
      * Not thread safe.
      */
     void addCursorRow(MatrixCursor cursor, ZipArchiveEntry entry) {
         final MatrixCursor.RowBuilder row = cursor.newRow();
         final ArchiveId parsedId = createArchiveId(getEntryPath(entry));
         row.add(Document.COLUMN_DOCUMENT_ID, parsedId.toDocumentId());

         final File file = new File(entry.getName());
         row.add(Document.COLUMN_DISPLAY_NAME, file.getName());
         row.add(Document.COLUMN_SIZE, entry.getSize());

         final String mimeType = getMimeTypeForEntry(entry);
         row.add(Document.COLUMN_MIME_TYPE, mimeType);

         int flags = mimeType.startsWith("image/") ? Document.FLAG_SUPPORTS_THUMBNAIL : 0;
         if (MetadataReader.isSupportedMimeType(mimeType)) {
             flags |= Document.FLAG_SUPPORTS_METADATA;
         }
         row.add(Document.COLUMN_FLAGS, flags);
     }

     static String getMimeTypeForEntry(ZipArchiveEntry entry) {
         if (entry.isDirectory()) {
             return Document.MIME_TYPE_DIR;
         }

         final int lastDot = entry.getName().lastIndexOf('.');
         if (lastDot >= 0) {
             final String extension = entry.getName().substring(lastDot + 1).toLowerCase(Locale.US);
             final String mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
             if (mimeType != null) {
                 return mimeType;
             }
         }

         return "application/octet-stream";
     }

     // TODO: Upstream to the Preconditions class.
     // TODO: Move to a separate file.
     public static class MorePreconditions {
         static void checkArgumentEquals(String expected, @Nullable String actual,
                 String message) {
             if (!TextUtils.equals(expected, actual)) {
                 throw new IllegalArgumentException(String.format(message,
                         String.valueOf(expected), String.valueOf(actual)));
             }
         }

         static void checkArgumentEquals(Uri expected, @Nullable Uri actual,
                 String message) {
             checkArgumentEquals(expected.toString(), actual.toString(), message);
         }
     }
 };
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.documentsui.archives;

	import android.content.Context;
	import android.content.res.AssetFileDescriptor;
	import android.database.Cursor;
	import android.database.MatrixCursor;
	import android.graphics.Point;
	import android.net.Uri;
	import android.os.CancellationSignal;
	import android.os.ParcelFileDescriptor;
	import android.provider.DocumentsContract.Document;
	import android.provider.MetadataReader;
	import android.system.ErrnoException;
	import android.system.Os;
	import android.system.OsConstants;
	import android.text.TextUtils;
	import android.webkit.MimeTypeMap;

	import androidx.annotation.GuardedBy;
	import androidx.annotation.Nullable;
	import androidx.core.util.Preconditions;

	import java.io.Closeable;
	import java.io.File;
	import java.io.FileNotFoundException;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Locale;
	import java.util.Map;

	import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;

	/**
	* Provides basic implementation for creating, extracting and accessing
	* files within archives exposed by a document provider.
	*
	* <p>This class is thread safe.
	*/
	public abstract class Archive implements Closeable {
	private static final String TAG = "Archive";

	public static final String[] DEFAULT_PROJECTION = new String[] {
	Document.COLUMN_DOCUMENT_ID,
	Document.COLUMN_DISPLAY_NAME,
	Document.COLUMN_MIME_TYPE,
	Document.COLUMN_SIZE,
	Document.COLUMN_FLAGS
	};

	final Context mContext;
	final Uri mArchiveUri;
	final int mAccessMode;
	final Uri mNotificationUri;

	// The container as well as values are guarded by mEntries.
	@GuardedBy("mEntries")
	final Map<String, ZipArchiveEntry> mEntries;

	// The container as well as values and elements of values are guarded by mEntries.
	@GuardedBy("mEntries")
	final Map<String, List<ZipArchiveEntry>> mTree;

	Archive(
	Context context,
	Uri archiveUri,
	int accessMode,
	@Nullable Uri notificationUri) {
	mContext = context;
	mArchiveUri = archiveUri;
	mAccessMode = accessMode;
	mNotificationUri = notificationUri;

	mTree = new HashMap<>();
	mEntries = new HashMap<>();
	}

	/**
	* Returns a valid, normalized path for an entry.
	*/
	public static String getEntryPath(ZipArchiveEntry entry) {
	Preconditions.checkArgument(entry.isDirectory() == entry.getName().endsWith("/"),
	"Ill-formated ZIP-file.");
	if (entry.getName().startsWith("/")) {
	return entry.getName();
	} else {
	return "/" + entry.getName();
	}
	}

	/**
	* Returns true if the file descriptor is seekable.
	* @param descriptor File descriptor to check.
	*/
	public static boolean canSeek(ParcelFileDescriptor descriptor) {
	try {
	return Os.lseek(descriptor.getFileDescriptor(), 0,
	OsConstants.SEEK_CUR) == 0;
	} catch (ErrnoException e) {
	return false;
	}
	}

	/**
	* Lists child documents of an archive or a directory within an
	* archive. Must be called only for archives with supported mime type,
	* or for documents within archives.
	*
	* @see DocumentsProvider.queryChildDocuments(String, String[], String)
	*/
	public Cursor queryChildDocuments(String documentId, @Nullable String[] projection,
	@Nullable String sortOrder) throws FileNotFoundException {
	final ArchiveId parsedParentId = ArchiveId.fromDocumentId(documentId);
	MorePreconditions.checkArgumentEquals(mArchiveUri, parsedParentId.mArchiveUri,
	"Mismatching archive Uri. Expected: %s, actual: %s.");

	final MatrixCursor result = new MatrixCursor(
	projection != null ? projection : DEFAULT_PROJECTION);
	if (mNotificationUri != null) {
	result.setNotificationUri(mContext.getContentResolver(), mNotificationUri);
	}

	synchronized (mEntries) {
	final List<ZipArchiveEntry> parentList = mTree.get(parsedParentId.mPath);
	if (parentList == null) {
	throw new FileNotFoundException();
	}
	for (final ZipArchiveEntry entry : parentList) {
	addCursorRow(result, entry);
	}
	}
	return result;
	}

	/**
	* Returns a MIME type of a document within an archive.
	*
	* @see DocumentsProvider.getDocumentType(String)
	*/
	public String getDocumentType(String documentId) throws FileNotFoundException {
	final ArchiveId parsedId = ArchiveId.fromDocumentId(documentId);
	MorePreconditions.checkArgumentEquals(mArchiveUri, parsedId.mArchiveUri,
	"Mismatching archive Uri. Expected: %s, actual: %s.");

	synchronized (mEntries) {
	final ZipArchiveEntry entry = mEntries.get(parsedId.mPath);
	if (entry == null) {
	throw new FileNotFoundException();
	}
	return getMimeTypeForEntry(entry);
	}
	}

	/**
	* Returns true if a document within an archive is a child or any descendant of the archive
	* document or another document within the archive.
	*
	* @see DocumentsProvider.isChildDocument(String, String)
	*/
	public boolean isChildDocument(String parentDocumentId, String documentId) {
	final ArchiveId parsedParentId = ArchiveId.fromDocumentId(parentDocumentId);
	final ArchiveId parsedId = ArchiveId.fromDocumentId(documentId);
	MorePreconditions.checkArgumentEquals(mArchiveUri, parsedParentId.mArchiveUri,
	"Mismatching archive Uri. Expected: %s, actual: %s.");

	synchronized (mEntries) {
	final ZipArchiveEntry entry = mEntries.get(parsedId.mPath);
	if (entry == null) {
	return false;
	}

	final ZipArchiveEntry parentEntry = mEntries.get(parsedParentId.mPath);
	if (parentEntry == null \|\| !parentEntry.isDirectory()) {
	return false;
	}

	// Add a trailing slash even if it's not a directory, so it's easy to check if the
	// entry is a descendant.
	String pathWithSlash = entry.isDirectory() ? getEntryPath(entry)
	: getEntryPath(entry) + "/";

	return pathWithSlash.startsWith(parsedParentId.mPath) &&
	!parsedParentId.mPath.equals(pathWithSlash);
	}
	}

	/**
	* Returns metadata of a document within an archive.
	*
	* @see DocumentsProvider.queryDocument(String, String[])
	*/
	public Cursor queryDocument(String documentId, @Nullable String[] projection)
	throws FileNotFoundException {
	final ArchiveId parsedId = ArchiveId.fromDocumentId(documentId);
	MorePreconditions.checkArgumentEquals(mArchiveUri, parsedId.mArchiveUri,
	"Mismatching archive Uri. Expected: %s, actual: %s.");

	synchronized (mEntries) {
	final ZipArchiveEntry entry = mEntries.get(parsedId.mPath);
	if (entry == null) {
	throw new FileNotFoundException();
	}

	final MatrixCursor result = new MatrixCursor(
	projection != null ? projection : DEFAULT_PROJECTION);
	if (mNotificationUri != null) {
	result.setNotificationUri(mContext.getContentResolver(), mNotificationUri);
	}
	addCursorRow(result, entry);
	return result;
	}
	}

	/**
	* Creates a file within an archive.
	*
	* @see DocumentsProvider.createDocument(String, String, String))
	*/
	public String createDocument(String parentDocumentId, String mimeType, String displayName)
	throws FileNotFoundException {
	throw new UnsupportedOperationException("Creating documents not supported.");
	}

	/**
	* Opens a file within an archive.
	*
	* @see DocumentsProvider.openDocument(String, String, CancellationSignal))
	*/
	public ParcelFileDescriptor openDocument(
	String documentId, String mode, @Nullable final CancellationSignal signal)
	throws FileNotFoundException {
	throw new UnsupportedOperationException("Opening not supported.");
	}

	/**
	* Opens a thumbnail of a file within an archive.
	*
	* @see DocumentsProvider.openDocumentThumbnail(String, Point, CancellationSignal))
	*/
	public AssetFileDescriptor openDocumentThumbnail(
	String documentId, Point sizeHint, final CancellationSignal signal)
	throws FileNotFoundException {
	throw new UnsupportedOperationException("Thumbnails not supported.");
	}

	/**
	* Creates an archive id for the passed path.
	*/
	public ArchiveId createArchiveId(String path) {
	return new ArchiveId(mArchiveUri, mAccessMode, path);
	}

	/**
	* Not thread safe.
	*/
	void addCursorRow(MatrixCursor cursor, ZipArchiveEntry entry) {
	final MatrixCursor.RowBuilder row = cursor.newRow();
	final ArchiveId parsedId = createArchiveId(getEntryPath(entry));
	row.add(Document.COLUMN_DOCUMENT_ID, parsedId.toDocumentId());

	final File file = new File(entry.getName());
	row.add(Document.COLUMN_DISPLAY_NAME, file.getName());
	row.add(Document.COLUMN_SIZE, entry.getSize());

	final String mimeType = getMimeTypeForEntry(entry);
	row.add(Document.COLUMN_MIME_TYPE, mimeType);

	int flags = mimeType.startsWith("image/") ? Document.FLAG_SUPPORTS_THUMBNAIL : 0;
	if (MetadataReader.isSupportedMimeType(mimeType)) {
	flags \|= Document.FLAG_SUPPORTS_METADATA;
	}
	row.add(Document.COLUMN_FLAGS, flags);
	}

	static String getMimeTypeForEntry(ZipArchiveEntry entry) {
	if (entry.isDirectory()) {
	return Document.MIME_TYPE_DIR;
	}

	final int lastDot = entry.getName().lastIndexOf('.');
	if (lastDot >= 0) {
	final String extension = entry.getName().substring(lastDot + 1).toLowerCase(Locale.US);
	final String mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
	if (mimeType != null) {
	return mimeType;
	}
	}

	return "application/octet-stream";
	}

	// TODO: Upstream to the Preconditions class.
	// TODO: Move to a separate file.
	public static class MorePreconditions {
	static void checkArgumentEquals(String expected, @Nullable String actual,
	String message) {
	if (!TextUtils.equals(expected, actual)) {
	throw new IllegalArgumentException(String.format(message,
	String.valueOf(expected), String.valueOf(actual)));
	}
	}

	static void checkArgumentEquals(Uri expected, @Nullable Uri actual,
	String message) {
	checkArgumentEquals(expected.toString(), actual.toString(), message);
	}
	}
	};