The main theme of this change is encapsulation. This change
preserves all existing functionality but the implementation
is now much cleaner.
Instead of a "database lock", access to the database is treated
as a resource acquisition problem. If a thread's owns a database
connection, then it can access the database; otherwise, it must
acquire a database connection first, and potentially wait for other
threads to give up theirs. The SQLiteConnectionPool encapsulates
the details of how connections are created, configured, acquired,
released and disposed.
One new feature is that SQLiteConnectionPool can make scheduling
decisions about which thread should next acquire a database
connection when there is contention among threads. The factors
considered include wait queue ordering (fairness among peers),
whether the connection is needed for an interactive operation
(unfairness on behalf of the UI), and whether the primary connection
is needed or if any old connection will do. Thus one goal of the
new SQLiteConnectionPool is to improve the utilization of
database connections.
To emulate some quirks of the old "database lock," we introduce
the concept of the primary database connection. The primary
database connection is the one that is typically used to perform
write operations to the database. When a thread holds the primary
database connection, it effectively prevents other threads from
modifying the database (although they can still read). What's
more, those threads will block when they try to acquire the primary
connection, which provides the same kind of mutual exclusion
features that the old "database lock" had. (In truth, we
probably don't need to be requiring use of the primary database
connection in as many places as we do now, but we can seek to refine
that behavior in future patches.)
Another significant change is that native sqlite3_stmt objects
(prepared statements) are fully encapsulated by the SQLiteConnection
object that owns them. This ensures that the connection can
finalize (destroy) all extant statements that belong to a database
connection when the connection is closed. (In the original code,
this was very complicated because the sqlite3_stmt objects were
managed by SQLiteCompiledSql objects which had different lifetime
from the original SQLiteDatabase that created them. Worse, the
SQLiteCompiledSql finalizer method couldn't actually destroy the
sqlite3_stmt objects because it ran on the finalizer thread and
therefore could not guarantee that it could acquire the database
lock in order to do the work. This resulted in some rather
tortured logic involving a list of pending finalizable statements
and a high change of deadlocks or leaks.)
Because sqlite3_stmt objects never escape the confines of the
SQLiteConnection that owns them, we can also greatly simplify
the design of the SQLiteProgram, SQLiteQuery and SQLiteStatement
objects. They no longer have to wrangle a native sqlite3_stmt
object pointer and manage its lifecycle. So now all they do
is hold bind arguments and provide a fancy API.
All of the JNI glue related to managing database connections
and performing transactions is now bound to SQLiteConnection
(rather than being scattered everywhere). This makes sense because
SQLiteConnection owns the native sqlite3 object, so it is the
only class in the system that can interact with the native
SQLite database directly. Encapsulation for the win.
One particularly tricky part of this change is managing the
ownership of SQLiteConnection objects. At any given time,
a SQLiteConnection is either owned by a SQLiteConnectionPool
or by a SQLiteSession. SQLiteConnections should never be leaked,
but we handle that case too (and yell about it with CloseGuard).
A SQLiteSession object is responsible for acquiring and releasing
a SQLiteConnection object on behalf of a single thread as needed.
For example, the session acquires a connection when a transaction
begins and releases it when finished. If the session cannot
acquire a connection immediately, then the requested operation
blocks until a connection becomes available.
SQLiteSessions are thread-local. A SQLiteDatabase assigns a
distinct session to each thread that performs database operations.
This is very very important. First, it prevents two threads
from trying to use the same SQLiteConnection at the same time
(because two threads can't share the same session).
Second, it prevents a single thread from trying to acquire two
SQLiteConnections simultaneously from the same database (because
a single thread can't have two sessions for the same database which,
in addition to being greedy, could result in a deadlock).
There is strict layering between the various database objects,
objects at lower layers are not aware of objects at higher layers.
Moreover, objects at higher layers generally own objects at lower
layers and are responsible for ensuring they are properly disposed
when no longer needed (good for the environment).
API layer: SQLiteDatabase, SQLiteProgram, SQLiteQuery, SQLiteStatement.
Session layer: SQLiteSession.
Connection layer: SQLiteConnectionPool, SQLiteConnection.
Native layer: JNI glue.
By avoiding cyclic dependencies between layers, we make the
architecture much more intelligible, maintainable and robust.
Finally, this change adds a great deal of new debugging information.
It is now possible to view a list of the most recent database
operations including how long they took to run using
"adb shell dumpsys dbinfo". (Because most of the interesting
work happens in SQLiteConnection, it is easy to add debugging
instrumentation to track all database operations in one place.)
Change-Id: Iffb4ce72d8bcf20b4e087d911da6aa84d2f15297
o Lots of documentation fixes.
o Add NdefMessage(NdefRecord ... records) ctor
o Add NdefRecord.createMime()
o Add NdefRecord.createExternal()
o Add toString(), equals() and hashCode() implementations
o Deprecate NdefRecord(byte[]) and NdefRecord.toByteArray()
o Remove framework dependency on libnfc_ndef.so
o Remove NfcAdapter.getDefaultAdapter(), its been deprecated a while
next step:
o Attempt to move NdefMessage -> Intent conversion into NDEF, and
make it CTS tested. This will ensure consistent NDEF -> Intent
mapping across all Android devices.
Change-Id: Ifed4910caa9a1d6bad32dbf0a507ab22bca35e22
This change simplifies the code associated with receiving input
events from input channels and makes it more robust. It also
does a better job of ensuring that input events are properly
recycled (sometimes we dropped them on the floor).
This change also adds a sequence number to all events, which is
handy for determining whether we are looking at the same event or a
new one, particularly when events are recycled.
Change-Id: I4ebd88f73b5f77f3e150778cd550e7f91956aac2
* Instead of javaland trying to write commands to
/proc/net/xt_qtaguid/ctrl
use the libcutils/qtaguid.c support via JNI.
* Get rid of tagToKernel() handled by qtaguid library.
Requires libcutils changes from c/132538/
Change-Id: I9de5b3fa4a596c56835024c6d376769a0eea7db1
This removes the ParcelSurfaceTexture class since that functionality has been
folded into Surface.java. The change also updates the MediaPlayer to get rid
of setParcelSurfaceTexture() and modifies setTexture() to use the new Surface
functionality in order to simplify the code.
Change-Id: Iafa75ea3188263928128325d8a726786971b4de4
The built-in ZipFile class was quite a long time to find an unpack
libraries. Move everything to using the libutils ZipFileRO class that
goes quite a bit faster. Initial measurements are 6 times faster than
the Java code.
Also, read files off the disk and compare their CRC against the APK's
CRC to see if we need to write the new file to disk. This also cuts down
the bootup time by up to a second per APK that has native files.
Change-Id: Ic464a7969a17368fb6a6b81d026888c4136c7603
This adds a new ParcelSurfaceTexture.java class that can be instantiated with
a SurfaceTexture and used to send the corresponding ISurfaceTexture interface
to another process via Binder. The ParcelSurfaceTexture java object can then
be used to create an ANativeWindow based on the SurfaceTextureClient interface.
Change-Id: Ie38ea948b866e52f36a6d0f6cde19b54a8546817
This is the basic infrastructure for pulling a full(*) backup of the
device's data over an adb(**) connection to the local device. The
basic process consists of these interacting pieces:
1. The framework's BackupManagerService, which coordinates the
collection of app data and routing to the destination.
2. A new framework-provided BackupAgent implementation called
FullBackupAgent, which is instantiated in the target applications'
processes in turn, and knows how to emit a datastream that contains
all of the app's saved data files.
3. A new shell-level program called "bu" that is used to bridge from
adb to the framework's Backup Manager.
4. adb itself, which now knows how to use 'bu' to kick off a backup
operation and pull the resulting data stream to the desktop host.
5. A system-provided application that verifies with the user that
an attempted backup/restore operation is in fact expected and to
be allowed.
The full agent implementation is not used during normal operation of
the delta-based app-customized remote backup process. Instead it's
used during user-confirmed *full* backup of applications and all their
data to a local destination, e.g. via the adb connection.
The output format is 'tar'. This makes it very easy for the end
user to examine the resulting dataset, e.g. for purpose of extracting
files for debug purposes; as well as making it easy to contemplate
adding things like a direct gzip stage to the data pipeline during
backup/restore. It also makes it convenient to construct and maintain
synthetic backup datasets for testing purposes.
Within the tar format, certain artificial conventions are used.
All files are stored within top-level directories according to
their semantic origin:
apps/pkgname/a/ : Application .apk file itself
apps/pkgname/obb/: The application's associated .obb containers
apps/pkgname/f/ : The subtree rooted at the getFilesDir() location
apps/pkgname/db/ : The subtree rooted at the getDatabasePath() parent
apps/pkgname/sp/ : The subtree rooted at the getSharedPrefsFile() parent
apps/pkgname/r/ : Files stored relative to the root of the app's file tree
apps/pkgname/c/ : Reserved for the app's getCacheDir() tree; not stored.
For each package, the first entry in the tar stream is a file called
"_manifest", nominally rooted at apps/pkgname. This file contains some
metadata about the package whose data is stored in the archive.
The contents of shared storage can optionally be included in the tar
stream. It is placed in the synthetic location:
shared/...
uid/gid are ignored; app uids are assigned at install time, and the
app's data is handled from within its own execution environment, so
will automatically have the app's correct uid.
Forward-locked .apk files are never backed up. System-partition
.apk files are not backed up unless they have been overridden by a
post-factory upgrade, in which case the current .apk *is* backed up --
i.e. the .apk that matches the on-disk data. The manifest preceding
each application's portion of the tar stream provides version numbers
and signature blocks for version checking, as well as an indication
of whether the restore logic should expect to install the .apk before
extracting the data.
System packages can designate their own full backup agents. This is
to manage things like the settings provider which (a) cannot be shut
down on the fly in order to do a clean snapshot of their file trees,
and (b) manage data that is not only irrelevant but actively hostile
to non-identical devices -- CDMA telephony settings would seriously
mess up a GSM device if emplaced there blind, for example.
When a full backup or restore is initiated from adb, the system will
present a confirmation UI that the user must explicitly respond to
within a short [~ 30 seconds] timeout. This is to avoid the
possibility of malicious desktop-side software secretly grabbing a copy
of all the user's data for nefarious purposes.
(*) The backup is not strictly a full mirror. In particular, the
settings database is not cloned; it is handled the same way that
it is in cloud backup/restore. This is because some settings
are actively destructive if cloned onto a different (or
especially a different-model) device: telephony settings and
AndroidID are good examples of this.
(**) On the framework side it doesn't care that it's adb; it just
sends the tar stream to a file descriptor. This can easily be
retargeted around whatever transport we might decide to use
in the future.
KNOWN ISSUES:
* the security UI is desperately ugly; no proper designs have yet
been done for it
* restore is not yet implemented
* shared storage backup is not yet implemented
* symlinks aren't yet handled, though some infrastructure for
dealing with them has been put in place.
Change-Id: Ia8347611e23b398af36ea22c36dff0a276b1ce91
Added a new PointerIcon API (hidden for now) for loading
pointer icons.
Fixed a starvation problem in the native Looper's sendMessage
implementation which caused new messages to be posted ahead
of old messages sent with sendMessageDelayed.
Redesigned the touch pad gestures to be defined in terms of
more fluid finger / spot movements. The objective is to reinforce
the natural mapping between fingers and spots which means there
must not be any discontinuities in spot motion relative to
the fingers.
Removed the SpotController stub and folded its responsibilities
into PointerController.
Change-Id: I5126b1e69d95252fda7f2a684c9287e239a57163
This seems simpler and more contained, and I think the comment explaining
why hoop-jumping is necessary is a bit clearer now.
Change-Id: Ief4afd7cbb42188ed835fce23e497520bdb753a8
In addition to the primary change in the subject, also some minor cleanup of javadoc, typos, CloseGuard warning, etc found while working on a new AbstractAccountAuthenticator.
Change-Id: I73f3408773a43a0021a15f8d051fd3dbbdf898a5
Replaced VelocityTracker with a faster and more accurate
native implementation. This avoids the duplicate maintenance
overhead of having two implementations.
The new algorithm requires that the sample duration be at least
10ms in order to contribute to the velocity calculation. This
ensures that the velocity is not severely overestimated when
samples arrive in bursts.
The new algorithm computes the exponentially weighted moving
average using weights based on the relative duration of successive
sample periods.
The new algorithm is also more careful about how it handles
individual pointers going down or up and their effects on the
collected movement traces. The intent is to preserve the last
known velocity of pointers as they go up while also ensuring
that other motion samples do not count twice in that case.
Bug: 4086785
Change-Id: I2632321232c64d6b8faacdb929e33f60e64dcdd3
UsbDevice is now just an immutable parcelable object like UsbInterface and
UsbEndpoint.
All IO related functionality is now contained in UsbDeviceConnection
and UsbRequest.
Bug: 4067029
Change-Id: Ia84da0b512a697acc940eee0c3566711c62e1a68
Signed-off-by: Mike Lockwood <lockwood@android.com>
UsbManager:
- is now a service retrievable via Context.getSystemService(Context.USB_SERVICE).
- provides support for returning a list all connected USB devices
- broadcasts ACTION_USB_DEVICE_ATTACHED and USB_DEVICE_DETACHED when devices
are added and removed from the USB host bus
UsbDevice:
- represents an attached USB device.
UsbInterface:
- represents an interface on a USB device
- devices may have multiple interfaces if they provide multiple
sets of functionality (for example, android phones typically have interfaces
for both USB mass storage and adb)
UsbEndpoint:
- represents an endpoint on a USB interface
- endpoints are used for sending or receiving data
(only in one or the other direction)
UsbRequest:
- encapsulates a send or receive request to be sent over an endpoint
Change-Id: Ieef3e434c62760770ea839070cf5eba1a705967a
Signed-off-by: Mike Lockwood <lockwood@android.com>
This enables the system bar to carve out a region through which
events will be sent to the IME behind it.
Bug: 3238092
Change-Id: I69b855a8d9b5b3ee525266c0861826e53e5b5028
A new USB host API will be added in an upcoming commit
Change-Id: I5816c10c7acd236d31ab8ae255fc83c77121eea0
Signed-off-by: Mike Lockwood <lockwood@android.com>
NFC service is now an application service in packages/apps/Nfc.
NFC service is registered through ServiceManager.addService(), and the proxy
object NfcAdapter obtains a handle to it through ServiceManager.getService().
**Important** Had to add new symbols AID_NFC / NFC_UID / android.uid.nfc and
modify service_manager.c, Process.java and PackageManagerService.java in order
to force the com.android.nfc process to take a fixed uid, so that it can use
ServiceManager.addService().
Most of the JNI has moved to packages/apps/Nfc/jni. However NdefRecord and
NdefMessage require some in-process native code, so android_com_NdefMessage.cpp
and android_com_NdefRecord.cpp stay in frameworks/base/core/jni. They link to
a very small library libnfc_ndef.so that implements NDEF message parsing. This
has been added to core.mk so all devices (even without NFC hardware) can work
with NDEF data.
Bug: 3041259
Bug: 3097445
Change-Id: If7f00cd8f2053acfc9319ca366d4a9c02bd396e6
Signed-off-by: Nick Pelly <npelly@google.com>
