Merge "Restore file truncation where expected." into sc-dev (02b741f8) · Commits · e / os / android_frameworks_base

core/java/android/content/ContentProvider.java

+15 −22

Original line number	Diff line number	Diff line
		@@ -1885,9 +1885,9 @@ public abstract class ContentProvider implements ContentInterface, ComponentCall
		* in {@link android.provider.MediaStore.MediaColumns}.</p>
		*
		* @param uri The URI whose file is to be opened.
		* @param mode Access mode for the file. May be "r" for read-only access,
		* "rw" for read and write access, or "rwt" for read and write access
		* that truncates any existing file.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		*
		* @return Returns a new ParcelFileDescriptor which you can use to access
		* the file.
		@@ -1948,10 +1948,9 @@ public abstract class ContentProvider implements ContentInterface, ComponentCall
		* in {@link android.provider.MediaStore.MediaColumns}.</p>
		*
		* @param uri The URI whose file is to be opened.
		* @param mode Access mode for the file. May be "r" for read-only access,
		* "w" for write-only access, "rw" for read and write access, or
		* "rwt" for read and write access that truncates any existing
		* file.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @param signal A signal to cancel the operation in progress, or
		* {@code null} if none. For example, if you are downloading a
		* file from the network to service a "rw" mode request, you
		@@ -2011,11 +2010,9 @@ public abstract class ContentProvider implements ContentInterface, ComponentCall
		* containing at least the columns specified by {@link android.provider.OpenableColumns}.</p>
		*
		* @param uri The URI whose file is to be opened.
		* @param mode Access mode for the file. May be "r" for read-only access,
		* "w" for write-only access (erasing whatever data is currently in
		* the file), "wa" for write-only access to append to any existing data,
		* "rw" for read and write access on any existing data, and "rwt" for read
		* and write access that truncates any existing file.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		*
		* @return Returns a new AssetFileDescriptor which you can use to access
		* the file.
		@@ -2068,11 +2065,9 @@ public abstract class ContentProvider implements ContentInterface, ComponentCall
		* containing at least the columns specified by {@link android.provider.OpenableColumns}.</p>
		*
		* @param uri The URI whose file is to be opened.
		* @param mode Access mode for the file. May be "r" for read-only access,
		* "w" for write-only access (erasing whatever data is currently in
		* the file), "wa" for write-only access to append to any existing data,
		* "rw" for read and write access on any existing data, and "rwt" for read
		* and write access that truncates any existing file.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @param signal A signal to cancel the operation in progress, or
		* {@code null} if none. For example, if you are downloading a
		* file from the network to service a "rw" mode request, you
		@@ -2103,11 +2098,9 @@ public abstract class ContentProvider implements ContentInterface, ComponentCall
		* by looking up a column named "_data" at the given URI.
		*
		* @param uri The URI to be opened.
		* @param mode The file mode. May be "r" for read-only access,
		* "w" for write-only access (erasing whatever data is currently in
		* the file), "wa" for write-only access to append to any existing data,
		* "rw" for read and write access on any existing data, and "rwt" for read
		* and write access that truncates any existing file.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		*
		* @return Returns a new ParcelFileDescriptor that can be used by the
		* client to access the file.

core/java/android/content/ContentResolver.java

+73 −13

Original line number	Diff line number	Diff line
		@@ -63,7 +63,9 @@ import android.os.RemoteException;
		import android.os.ServiceManager;
		import android.os.SystemClock;
		import android.os.UserHandle;
		import android.system.ErrnoException;
		import android.system.Int64Ref;
		import android.system.Os;
		import android.text.TextUtils;
		import android.util.EventLog;
		import android.util.Log;
		@@ -76,8 +78,10 @@ import com.android.internal.util.MimeIconUtils;
		import dalvik.system.CloseGuard;

		import java.io.File;
		import java.io.FileDescriptor;
		import java.io.FileInputStream;
		import java.io.FileNotFoundException;
		import java.io.FileOutputStream;
		import java.io.IOException;
		import java.io.InputStream;
		import java.io.OutputStream;
		@@ -864,6 +868,20 @@ public abstract class ContentResolver implements ContentInterface {
		return wrap((ContentInterface) wrapped);
		}

		/**
		* Offer to locally truncate the given file when opened using the write-only
		* mode. This is typically used to preserve legacy compatibility behavior.
		*/
		private static void maybeTruncate(FileDescriptor fd, String mode) throws FileNotFoundException {
		if ("w".equals(mode)) {
		try {
		Os.ftruncate(fd, 0);
		} catch (ErrnoException e) {
		throw new FileNotFoundException("Failed to truncate: " + e.getMessage());
		}
		}
		}

		/** @hide */
		@SuppressWarnings("HiddenAbstractMethod")
		@UnsupportedAppUsage
		@@ -1525,8 +1543,20 @@ public abstract class ContentResolver implements ContentInterface {
		}

		/**
		* Synonym for {@link #openOutputStream(Uri, String)
		* openOutputStream(uri, "w")}.
		* Open a stream on to the content associated with a content URI. If there
		* is no data associated with the URI, FileNotFoundException is thrown.
		*
		* <h5>Accepts the following URI schemes:</h5>
		* <ul>
		* <li>content ({@link #SCHEME_CONTENT})</li>
		* <li>file ({@link #SCHEME_FILE})</li>
		* </ul>
		*
		* <p>See {@link #openAssetFileDescriptor(Uri, String)} for more information
		* on these schemes.
		*
		* <p>This method behaves like {@link FileOutputStream} and automatically
		* truncates any existing contents.
		*
		* @param uri The desired URI.
		* @return an OutputStream or {@code null} if the provider recently crashed.
		@@ -1534,7 +1564,16 @@ public abstract class ContentResolver implements ContentInterface {
		*/
		public final @Nullable OutputStream openOutputStream(@NonNull Uri uri)
		throws FileNotFoundException {
		return openOutputStream(uri, "w");
		AssetFileDescriptor fd = openAssetFileDescriptor(uri, "w", null);
		if (fd == null) return null;
		try {
		final FileOutputStream res = fd.createOutputStream();
		// Unconditionally truncate to mirror FileOutputStream behavior
		maybeTruncate(res.getFD(), "w");
		return res;
		} catch (IOException e) {
		throw new FileNotFoundException("Unable to create stream");
		}
		}

		/**
		@@ -1551,7 +1590,9 @@ public abstract class ContentResolver implements ContentInterface {
		* on these schemes.
		*
		* @param uri The desired URI.
		* @param mode May be "w", "wa", "rw", or "rwt".
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @return an OutputStream or {@code null} if the provider recently crashed.
		* @throws FileNotFoundException if the provided URI could not be opened.
		* @see #openAssetFileDescriptor(Uri, String)
		@@ -1559,8 +1600,14 @@ public abstract class ContentResolver implements ContentInterface {
		public final @Nullable OutputStream openOutputStream(@NonNull Uri uri, @NonNull String mode)
		throws FileNotFoundException {
		AssetFileDescriptor fd = openAssetFileDescriptor(uri, mode, null);
		if (fd == null) return null;
		try {
		return fd != null ? fd.createOutputStream() : null;
		final FileOutputStream res = fd.createOutputStream();
		// Preserve legacy behavior by offering to truncate
		if (mTargetSdkVersion < Build.VERSION_CODES.Q) {
		maybeTruncate(res.getFD(), mode);
		}
		return res;
		} catch (IOException e) {
		throw new FileNotFoundException("Unable to create stream");
		}
		@@ -1607,8 +1654,9 @@ public abstract class ContentResolver implements ContentInterface {
		* provider, use {@link ParcelFileDescriptor#closeWithError(String)}.
		*
		* @param uri The desired URI to open.
		* @param mode The file mode to use, as per {@link ContentProvider#openFile
		* ContentProvider.openFile}.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @return Returns a new ParcelFileDescriptor pointing to the file or {@code null} if the
		* provider recently crashed. You own this descriptor and are responsible for closing it
		* when done.
		@@ -1650,8 +1698,9 @@ public abstract class ContentResolver implements ContentInterface {
		* provider, use {@link ParcelFileDescriptor#closeWithError(String)}.
		*
		* @param uri The desired URI to open.
		* @param mode The file mode to use, as per {@link ContentProvider#openFile
		* ContentProvider.openFile}.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @param cancellationSignal A signal to cancel the operation in progress,
		* or null if none. If the operation is canceled, then
		* {@link OperationCanceledException} will be thrown.
		@@ -1744,8 +1793,9 @@ public abstract class ContentResolver implements ContentInterface {
		* from any built-in data conversion that a provider implements.
		*
		* @param uri The desired URI to open.
		* @param mode The file mode to use, as per {@link ContentProvider#openAssetFile
		* ContentProvider.openAssetFile}.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @return Returns a new ParcelFileDescriptor pointing to the file or {@code null} if the
		* provider recently crashed. You own this descriptor and are responsible for closing it
		* when done.
		@@ -1798,8 +1848,9 @@ public abstract class ContentResolver implements ContentInterface {
		* from any built-in data conversion that a provider implements.
		*
		* @param uri The desired URI to open.
		* @param mode The file mode to use, as per {@link ContentProvider#openAssetFile
		* ContentProvider.openAssetFile}.
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt". See
		* {@link ParcelFileDescriptor#parseMode} for more details.
		* @param cancellationSignal A signal to cancel the operation in progress, or null if
		* none. If the operation is canceled, then
		* {@link OperationCanceledException} will be thrown.
		@@ -1835,6 +1886,10 @@ public abstract class ContentResolver implements ContentInterface {
		} else if (SCHEME_FILE.equals(scheme)) {
		ParcelFileDescriptor pfd = ParcelFileDescriptor.open(
		new File(uri.getPath()), ParcelFileDescriptor.parseMode(mode));
		// Preserve legacy behavior by offering to truncate
		if (mTargetSdkVersion < Build.VERSION_CODES.Q) {
		maybeTruncate(pfd.getFileDescriptor(), mode);
		}
		return new AssetFileDescriptor(pfd, 0, -1);
		} else {
		if ("r".equals(mode)) {
		@@ -1892,6 +1947,11 @@ public abstract class ContentResolver implements ContentInterface {
		// ParcelFileDescriptorInner do that when it is closed.
		stableProvider = null;

		// Preserve legacy behavior by offering to truncate
		if (mTargetSdkVersion < Build.VERSION_CODES.Q) {
		maybeTruncate(pfd.getFileDescriptor(), mode);
		}

		return new AssetFileDescriptor(pfd, fd.getStartOffset(),
		fd.getDeclaredLength());

core/java/android/os/ParcelFileDescriptor.java

+49 −9

Original line number	Diff line number	Diff line
		@@ -31,6 +31,7 @@ import static android.system.OsConstants.S_ISLNK;
		import static android.system.OsConstants.S_ISREG;
		import static android.system.OsConstants.S_IWOTH;

		import android.annotation.IntDef;
		import android.annotation.NonNull;
		import android.annotation.SuppressLint;
		import android.annotation.SystemApi;
		@@ -63,6 +64,8 @@ import java.io.FileOutputStream;
		import java.io.IOException;
		import java.io.InterruptedIOException;
		import java.io.UncheckedIOException;
		import java.lang.annotation.Retention;
		import java.lang.annotation.RetentionPolicy;
		import java.net.DatagramSocket;
		import java.net.Socket;
		import java.nio.ByteOrder;
		@@ -110,6 +113,20 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {

		private final CloseGuard mGuard = CloseGuard.get();

		/** @hide */
		@IntDef(prefix = {"MODE_"}, value = {
		MODE_WORLD_READABLE,
		MODE_WORLD_WRITEABLE,
		MODE_READ_ONLY,
		MODE_WRITE_ONLY,
		MODE_READ_WRITE,
		MODE_CREATE,
		MODE_TRUNCATE,
		MODE_APPEND,
		})
		@Retention(RetentionPolicy.SOURCE)
		public @interface Mode { }

		/**
		* For use with {@link #open}: if {@link #MODE_CREATE} has been supplied and
		* this file doesn't already exist, then create the file with permissions
		@@ -227,7 +244,8 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {
		* be opened with the requested mode.
		* @see #parseMode(String)
		*/
		public static ParcelFileDescriptor open(File file, int mode) throws FileNotFoundException {
		public static ParcelFileDescriptor open(File file, @Mode int mode)
		throws FileNotFoundException {
		final FileDescriptor fd = openInternal(file, mode);
		if (fd == null) return null;

		@@ -259,7 +277,7 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {
		// We can't accept a generic Executor here, since we need to use
		// MessageQueue.addOnFileDescriptorEventListener()
		@SuppressLint("ExecutorRegistration")
		public static ParcelFileDescriptor open(File file, int mode, Handler handler,
		public static ParcelFileDescriptor open(File file, @Mode int mode, Handler handler,
		final OnCloseListener listener) throws IOException {
		if (handler == null) {
		throw new IllegalArgumentException("Handler must not be null");
		@@ -330,7 +348,8 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {
		return pfd;
		}

		private static FileDescriptor openInternal(File file, int mode) throws FileNotFoundException {
		private static FileDescriptor openInternal(File file, @Mode int mode)
		throws FileNotFoundException {
		final int flags = FileUtils.translateModePfdToPosix(mode) \| ifAtLeastQ(O_CLOEXEC);

		int realMode = S_IRWXU \| S_IRWXG;
		@@ -623,15 +642,36 @@ public class ParcelFileDescriptor implements Parcelable, Closeable {
		}

		/**
		* Converts a string representing a file mode, such as "rw", into a bitmask suitable for use
		* with {@link #open}.
		* Converts a string representing a file mode, such as "rw", into a bitmask
		* suitable for use with {@link #open}.
		* <p>
		* @param mode The string representation of the file mode. Can be "r", "w", "wt", "wa", "rw"
		* or "rwt".
		* The argument must define at least one of the following base access modes:
		* <ul>
		* <li>"r" indicates the file should be opened in read-only mode, equivalent
		* to {@link OsConstants#O_RDONLY}.
		* <li>"w" indicates the file should be opened in write-only mode,
		* equivalent to {@link OsConstants#O_WRONLY}.
		* <li>"rw" indicates the file should be opened in read-write mode,
		* equivalent to {@link OsConstants#O_RDWR}.
		* </ul>
		* In addition to a base access mode, the following additional modes may
		* requested:
		* <ul>
		* <li>"a" indicates the file should be opened in append mode, equivalent to
		* {@link OsConstants#O_APPEND}. Before each write, the file offset is
		* positioned at the end of the file.
		* <li>"t" indicates the file should be opened in truncate mode, equivalent
		* to {@link OsConstants#O_TRUNC}. If the file already exists and is a
		* regular file and is opened for writing, it will be truncated to length 0.
		* </ul>
		*
		* @param mode The string representation of the file mode. Can be "r", "w",
		* "wt", "wa", "rw" or "rwt".
		* @return A bitmask representing the given file mode.
		* @throws IllegalArgumentException if the given string does not match a known file mode.
		* @throws IllegalArgumentException if the given string does not match a
		* known file mode.
		*/
		public static int parseMode(String mode) {
		public static @Mode int parseMode(String mode) {
		return FileUtils.translateModePosixToPfd(FileUtils.translateModeStringToPosix(mode));
		}