Merge commit 'ff04e97faf75c435e453d4c1caf7eeac8b9c1ceb'
* commit 'ff04e97faf75c435e453d4c1caf7eeac8b9c1ceb':
fix [2835280] Add support for cancelling buffers to ANativeWindow
There is a new ANativeWindow::cancelBuffer() API that can be used to
cancel any dequeued buffer, BEFORE it's been enqueued. The buffer is
returned to the list of availlable buffers. dequeue and cancel are not
mutually thread safe, they must be called from the same thread or
external synchronization must be used.
Change-Id: I86cc7985bace8b6a93ad2c75d2bef5c3c2cb4d61
Merge commit 'e11b76d3efb056edea301d53a354d0730adf3520'
* commit 'e11b76d3efb056edea301d53a354d0730adf3520':
Minor logging changes to input dispatcher to help with debugging.
This change narrows the opportunity for a race condition setting the
resource Configuration while devices are being updated.
Change-Id: I58efa563f4129ab0fce7108511d16a99dff7e451
Added dumpsys reporting to EventHub.
Made the formatting a bit clearer.
Added 'Locked' suffix to some internal methods of EventHub.
Change-Id: Ic449560bcce378f6361895d27c66854e9724abb0
Merge commit '57fa3e8b4c94125ddb5be015dd7fbde4a458894f'
* commit '57fa3e8b4c94125ddb5be015dd7fbde4a458894f':
Support haptic feedback for virtual keys defined in key layout.
This feature is currently used to enable dragging the start and end
selection handles of a TextView at the same time. Could be used for
other things later.
Deleted some dead code in ArrowKeyMovementMethod and CursorControllers.
Change-Id: I930accd97ca1ca1917aab8a807db2c950fc7b409
Redesigned the input dispatcher's ANR timeout mechanism so it is much
closer to Froyo's policy. ANR is only ever signalled if the dispatcher
is waiting on a window to finish processing its previous event(s) and
there is new pending input.
In the old code, we tracked the dispatch timeout separately for each
input channel. This was somewhat complicated and also resulted in the
situation where applications could ANR long after the user had pushed
them into the background.
Change-Id: I666ecada0952d4b95f1d67b9f733842b745c7f4b
As part of this change, consolidated and cleaned up the Looper API so
that there are fewer distinctions between the NDK and non-NDK declarations
(no need for two callback types, etc.).
Removed the dependence on specific constants from sys/poll.h such as
POLLIN. Instead looper.h defines events like LOOPER_EVENT_INPUT for
the events that it supports. That should help make any future
under-the-hood implementation changes easier.
Fixed a couple of compiler warnings along the way.
Change-Id: I449a7ec780bf061bdd325452f823673e2b39b6ae
There are 16 events logged in the event log:
SF_APP_DEQUEUE_BEFORE
SF_APP_DEQUEUE_AFTER
SF_APP_LOCK_BEFORE
SF_APP_LOCK_AFTER
SF_APP_QUEUE
SF_REPAINT
SF_COMPOSITION_COMPLETE
SF_UNLOCK_CLIENTS
SF_SWAP_BUFFERS
SF_REPAINT_DONE
SF_FB_POST_BEFORE
SF_FB_POST_AFTER
SF_FB_DEQUEUE_BEFORE
SF_FB_DEQUEUE_AFTER
SF_FB_LOCK_BEFORE
SF_FB_LOCK_AFTER
all events log the buffer conserned and a timestamp in microseconds.
by default the logging is not enabled, to turn it on:
adb shell service call SurfaceFlinger 1006 i31 1
adb shell setprop debug.graphic_log 1
The effect is immediate in SurfaceFlinger, but applications need to be
restarted.
Change-Id: Ifc2e31f7aed072d9a7dede20ff2ce59231edbec1
This change is essentially a rewrite of the main input dispatcher loop
with the target identification folded in. Since the input dispatcher now
has all of the window state, it can make better decisions about
when to ANR.
Added a .5 second deadline for processing app switch keys. This behavior
predates Gingerbread but had not previously been ported.
Fixed some timing inaccuracies in the ANR accounting that could cause
applications to ANR sooner than they should have.
Added a mechanism for tracking key and motion events that have been
dispatched to a window so that appropriate cancelation events can be
synthesized when recovering from ANR. This change helps to keep
applications in sync so they don't end up with stuck buttons upon
recovery from ANRs.
Added more comments to describe the tricky parts of PollLoop.
Change-Id: I13dffca27acb436fc383980db536abc4d8b9e6f1
Added the MotionEvent.FLAG_WINDOW_IS_OBSCURED flag which is set by the
input manager whenever another visible window is partly or wholly obscured
the target of a touch event so that applications can filter touches
accordingly.
Added a "filterTouchesWhenObscured" attribute to View which can be used to
enable filtering of touches when the view's window is obscured.
Change-Id: I936d9c85013fd2d77fb296a600528d30a29027d2
Finished the input device capability API.
Added a mechanism for calibrating touch devices to obtain more
accurate information about the touch contact area.
Improved pointer location to show new coordinates and capabilities.
Optimized pointer location display and formatting to avoid allocating large
numbers of temporary objects. The GC churn was causing the application to
stutter very badly when more than a couple of fingers were down).
Added more diagnostics.
Change-Id: Ie25380278ed6f16c5b04cd9df848015850383498
On single-touch devices, pointer up/down is signalled by a BTN_TOUCH
key event. Previously we handled BTN_TOUCH immediately but some drivers
may produce the sequence BTN_TOUCH, ABS_X, ABS_Y, SYN_REPORT on pointer down
which caused us to emit a bad initial pointer down location.
Now we wait for SYN_REPORT before reporting the up or down.
On multi-touch devices, pointer up can be signalled by as little as
the sequence SYN_MT_REPORT, SYN_REPORT. This change ensures that we
handle this case.
Added support for reading ABS_MT_PRESSURE when available.
Corrected mapping of touchMajor/touchMinor on single touch devices.
Minor code cleanup.
Change-Id: Ic7ec4811241ed85a06e59b8a839ca05180d491d4
Sometimes the wrong fd was accessed when the device was addressed
by device id.
The earlier implementation assumed that two arrays were in sync
but one of them was compacted when devices were removed. Instead
of that dependency the device now keeps track of it's file descriptor.
Change-Id: Ib0f320603aafb07ded354bc3687de9759c9068f2
Previously, the input dispatcher assumed that the input channel's
receive pipe file descriptor was a sufficiently unique identifier for
looking up input channels in its various tables. However, it can happen
that an input channel is disposed and then a new input channel is
immediately created that reuses the same file descriptor. Ordinarily
this is not a problem, however there is a small opportunity for a race
to arise in InputQueue.
When InputQueue receives an input event from the dispatcher, it
generates a finishedToken that encodes the channel's receive pipe fd,
and a sequence number. The finishedToken is used by the ViewRoot
as a handle for the event so that it can tell the InputQueue when
the event has finished being processed.
Here is the race:
1. InputQueue receives an input event, assigns a new finishedToken.
2. ViewRoot begins processing the input event.
3. During processing, ViewRoot unregisters the InputChannel.
4. A new InputChannel is created and is registered with the Input Queue.
This InputChannel happens to have the same receive pipe fd as
the one previously registered.
5. ViewRoot tells the InputQueue that it has finished processing the
input event, passing along the original finishedToken.
6. InputQueue throws an exception because the finishedToken's receive
pipe fd is registered but the sequence number is incorrect so it
assumes that the client has called finish spuriously.
The fix is to include a unique connection id within the finishedToken so
that the InputQueue can accurately confirm that the token belongs to
the currently registered InputChannel rather than to an old one that
happened to have the same receive pipe fd. When it notices this, it
ignores the spurious finish.
I've also made a couple of other small changes to avoid similar races
elsewhere.
This patch set also includes a fix to synthesize a finished signal
when the input channel is unregistered on the client side to
help keep the server and client in sync.
Bug: 2834068
Change-Id: I1de34a36249ab74c359c2c67a57e333543400f7b
Improved PointerLocation tool to use VelocityTracker more efficiently
and correctly when multiple pointers are down.
Fixed a bug in TouchInputMapper where it was not correctly copying
the id to index map in the last touch data. This could cause strange
behavior on secondary pointer up events.
Also added finished callback pooling in InputQueue.
Change-Id: Ia85e52ac2fb7350960ea1d7edfbe81a1b3e8267b
Also fixed bug where old touch screen size could be reported by
getMotionRange if an orientation change occurred but the user has not
yet touched the screen.
Bug: 2877345
Change-Id: I7878f47458f310ed6ebe6a5d1b2c9bec2c598ab9
Added a new asynchronous injection mode and made the existing
synchronization mechanism more robust.
Change-Id: Ia4aa04fd9b75ea2461a844c5b7933c831c1027e6
Refactored the input reader so that each raw input protocol is handled
by a separate subclass of the new InputMapper type. This way, behaviors
pertaining to keyboard, trackballs, touchscreens, switches and other
devices are clearly distinguished for improved maintainability.
Added partial support for describing capabilities of input devices
(incomplete and untested for now, will be fleshed out in later commits).
Simplified EventHub interface somewhat since InputReader is taking over
more of the work.
Cleaned up some of the interactions between InputManager and
WindowManagerService related to reading input state.
Fixed swiping finger from screen edge into display area.
Added logging of device information to 'dumpsys window'.
Change-Id: I17faffc33e3aec3a0f33f0b37e81a70609378612
This significantly re-works the native key dispatching code to
allow events to be pre-dispatched to the current IME before
being processed by native code. It introduces one new public
API, which must be called after retrieving an event if the app
wishes for it to be pre-dispatched.
Currently the native code will only do pre-dispatching of
system keys, to avoid significant overhead for gaming input.
This should be improved to be smarted, filtering for only
keys that the IME is interested in. Unfortunately IMEs don't
currently provide this information. :p
Change-Id: Ic1c7aeec8b348164957f2cd88119eb5bd85c2a9f
Added several new coordinate values to MotionEvents to capture
touch major/minor area, tool major/minor area and orientation.
Renamed NDK input constants per convention.
Added InputDevice class in Java which will eventually provide
useful information about available input devices.
Added APIs for manufacturing new MotionEvent objects with multiple
pointers and all necessary coordinate data.
Fixed a bug in the input dispatcher where it could get stuck with
a pointer down forever.
Fixed a bug in the WindowManager where the input window list could
end up containing stale removed windows.
Fixed a bug in the WindowManager where the input channel was being
removed only after the final animation transition had taken place
which caused spurious WINDOW DIED log messages to be printed.
Change-Id: Ie55084da319b20aad29b28a0499b8dd98bb5da68
And also:
- APIs to show and hide the IME, and control its interaction with the app.
- APIs to tell the app when its window resizes and needs to be redrawn.
- API to tell the app the content rectangle of its window (to layout
around the IME or status bar).
There is still a problem with IME interaction -- we need a way for the
app to deliver events to the IME before it handles them, so that for
example the back key will close the IME instead of finishing the app.
Change-Id: I37b75fc2ec533750ef36ca3aedd2f0cc0b5813cd
Also other cleanup and fixes:
- We now properly set the default window format to 565.
- New APIs to set the window format and flags from native code.
- Tweaked glue for simpler handling of the "destroy" message.
- Um, other stuff.
Change-Id: Id7790a21a2fa9a19b91854d225324a7c1e7c6ade
Removed old input dispatch code.
Refactored the policy callbacks.
Pushed a tiny bit of the power manager state down to native.
Fixed long press on MENU.
Made the virtual key detection and cancelation a bit more precise.
Change-Id: I5d8c1062f7ea0ab3b54c6fadb058c4d5f5a9e02e
This allows us to avoid exposing the file descriptor of
the event queue; instead, you attach an event queue to
a looper. This will also should allow native apps to be
written without the need for a separate thread, by attaching
the event queue to the main thread's looper and scheduling
their own messages there.
Change-Id: I38489282635895ae2cbfacb88599c1b1cad9b239
Not yet hooked up to anything in the NDK, but requires renaming
the existing android_native_window_t type everywhere.
Change-Id: Iffee6ea39c93b8b34e20fb69e4d2c7c837e5ea2e
This change mainly unwinds a premature optimization in the
dispatch pipeline.
To test HOME injection, run 'adb shell input keyevent 3'.
Change-Id: I1c4b7377c205da7c898014b8b07fc6dc1d46e4dd
The native code now maintains a list of all keys that may use
default handling. If the app finishes one of these keys
without handling it, the key will be passed back off to Java
for default treatment.
Change-Id: I6a842a0d728eeafa4de7142fae573f8c11099e18
Set a default orientation of ROTATION_0.
Added some more careful checks based on whether we have valid
absolute axis information from the driver.
Reset key repeating during configuration changes since the keyboard
device may have been removed.
Change-Id: I685960828acffcb17595fc5683309e8064a76714
Target identification is now fully native.
Fixed a couple of minor issues related to input injection.
Native input enabled by default, can be disabled by setting
WindowManagerPolicy.ENABLE_NATIVE_INPUT_DISPATCH to false.
Change-Id: I7edf66ed3e987cc9306ad4743ac57a116af452ff
Sometimes the wrong fd was accessed when the device was addressed
by device id.
The earlier implementation assumed that two arrays were in sync
but one of them was compacted when devices were removed. Instead
of that dependency the device now keeps track of it's file descriptor.
Change-Id: I2b8a793d76b89ab464ae830482b309fe86031671
Provides the basic infrastructure for a
NativeActivity's native code to get an object representing
its event stream that can be used to read input events.
Still work to do, probably some API changes, and reasonable
default key handling (so that for example back will still
work).
Change-Id: I6db891bc35dc9683181d7708eaed552b955a077e
Added ANRs handling.
Added event injection.
Fixed a NPE ActivityManagerServer writing ANRs to the drop box.
Fixed HOME key interception.
Fixed trackball reporting.
Fixed pointer rotation in landscape mode.
Change-Id: I50340f559f22899ab924e220a78119ffc79469b7
Added more tests.
Fixed a regression in Vector.
Fixed bugs in pointer tracking.
Fixed a starvation issue in PollLoop when setting or removing callbacks.
Fixed a couple of policy nits.
Modified the internal representation of MotionEvent to be more
efficient and more consistent.
Added code to skip/cancel virtual key processing when there are multiple
pointers down. This helps to better disambiguate virtual key presses
from stray touches (such as cheek presses).
Change-Id: I2a7d2cce0195afb9125b23378baa94fd2fc6671c
Refactored the code to eliminate potential deadlocks due to re-entrant
calls from the policy into the dispatcher. Also added some plumbing
that will be used to notify the framework about ANRs.
Change-Id: Iba7a10de0cb3c56cd7520d6ce716db52fdcc94ff
The old dispatch mechanism has been left in place and continues to
be used by default for now. To enable native input dispatch,
edit the ENABLE_NATIVE_DISPATCH constant in WindowManagerPolicy.
Includes part of the new input event NDK API. Some details TBD.
To wire up input dispatch, as the ViewRoot adds a window to the
window session it receives an InputChannel object as an output
argument. The InputChannel encapsulates the file descriptors for a
shared memory region and two pipe end-points. The ViewRoot then
provides the InputChannel to the InputQueue. Behind the
scenes, InputQueue simply attaches handlers to the native PollLoop object
that underlies the MessageQueue. This way MessageQueue doesn't need
to know anything about input dispatch per-se, it just exposes (in native
code) a PollLoop that other components can use to monitor file descriptor
state changes.
There can be zero or more targets for any given input event. Each
input target is specified by its input channel and some parameters
including flags, an X/Y coordinate offset, and the dispatch timeout.
An input target can request either synchronous dispatch (for foreground apps)
or asynchronous dispatch (fire-and-forget for wallpapers and "outside"
targets). Currently, finding the appropriate input targets for an event
requires a call back into the WindowManagerServer from native code.
In the future this will be refactored to avoid most of these callbacks
except as required to handle pending focus transitions.
End-to-end event dispatch mostly works!
To do: event injection, rate limiting, ANRs, testing, optimization, etc.
Change-Id: I8c36b2b9e0a2d27392040ecda0f51b636456de25
the new native_window_set_buffers_geometry allows
to specify a size and format for all buffers to be
dequeued. the buffer will be scalled to the window's
size.
Change-Id: I2c378b85c88d29cdd827a5f319d5c704d79ba381
this method can be used to change the number of buffers
associated to a native window. the default is two.
Change-Id: I608b959e6b29d77f95edb23c31dc9b099a758f2f
This change adds the methods necessary to use sp<> to handle refcounting
android_native_window_t and android_native_buffer_t. The new methods forward
the refcounting operations to the corresponding android_native_base_t
functions.
Change-Id: I7de8e262728e439bc1efdf69374a2a9f6f432ced
Merge commit 'f78964490d8098387d51444c87bf520ad3f674e2' into kraken
* commit 'f78964490d8098387d51444c87bf520ad3f674e2':
Add new keycodes for the convenience of Japanese IMEs
Call register_localized_collators() with the current locale.
Fixed deserialization problem in DatePicker.
Fix for bug 2467152 files with spaces fail to open.
Set alpha value for newly created dim surface.
telephony: Fix CID when CID is unknown
Add a Flattenable interface to libutils which can be used to flatten
an object into bytestream + filedescriptor stream.
Parcel is modified to handle Flattenable. And GraphicBuffer implements
Flattenable.
Except for the overlay classes libui is now independent of libbinder.
Surface::validate() could sometimes dereference a null pointer before checking it wasn't null.
This will prevent the application to crash when given bad parameters or used incorrectly.
However, the bug above probably has another cause.
we lost the concept of vertical stride when moving video playback to EGLImage.
Here we bring it back in a somewhat hacky-way that will work only for the
softgl/mdp backend.
Use EGLImageKHR instead of copybit directly.
We now have the basis to use streaming YUV textures (well, in fact
we already are). When/if we use the GPU instead of the MDP we'll
need to make sure it supports the appropriate YUV format.
Also make sure we compile if EGL_ANDROID_image_native_buffer is not supported
This also fixes [2152536] ANR in browser
When SF is enqueuing buffers faster than SF dequeues them.
The update flag in SF is not counted and under some situations SF will only
dequeue the first buffer. The state at this point is not technically
corrupted, it's valid, but just delayed by one buffer.
In the case of the Browser ANR, because the last enqueued buffer was delayed
the resizing of the current buffer couldn't happen.
The system would always fall back onto its feet if anything -else- in
tried to draw, because the "late" buffer would be picked up then.
When EGLImage extension is not available, SurfaceFlinger will fallback to using
glTexImage2D and glTexSubImage2D instead, which requires 50% more memory and an
extra copy. However this code path has never been exercised and had some bugs
which this patch fix.
Mainly the scale factor wasn't computed right when falling back on glDrawElements.
We also fallback to this mode of operation if a buffer doesn't have the adequate
usage bits for EGLImage usage.
This changes only code that is currently not executed. Some refactoring was needed to
keep the change clean. This doesn't change anything functionaly.
a new method, compostionComplete() is added to the framebuffer hal, it is used by surfaceflinger to signal the driver that the composition is complete, BEFORE it releases its client. This gives a chance to the driver to
Take 2. We needed to check that the usage flags are "good enough" as opposed to "the same".
This reverts commit 8f17a762fe9e9f31e4e86cb60ff2bfb6b10fdee6.
Rewrote SurfaceFlinger's buffer management from the ground-up.
The design now support an arbitrary number of buffers per surface, however the current implementation is limited to four. Currently only 2 buffers are used in practice.
The main new feature is to be able to dequeue all buffers at once (very important when there are only two).
A client can dequeue all buffers until there are none available, it can lock all buffers except the last one that is used for composition. The client will block then, until a new buffer is enqueued.
The current implementation requires that buffers are locked in the same order they are dequeued and enqueued in the same order they are locked. Only one buffer can be locked at a time.
eg. Allowed sequence: DQ, DQ, LOCK, Q, LOCK, Q
eg. Forbidden sequence: DQ, DQ, LOCK, LOCK, Q, Q
what happened is that the efective pixel format is calculated by SF but Surface nevew had access to it directly.
in particular this caused query(FORMAT) to return the requested format instead of the effective format.
This change makes SurfaceHolder.setType(GPU) obsolete (it's now ignored).
Added an API to android_native_window_t to allow extending the functionality without ever breaking binary compatibility. This is used to implement the new set_usage() API. This API needs to be called by software renderers because the default is to use usage flags suitable for h/w.
* changes:
update most gl tests to use EGLUtils
added two EGL helpers for selecting a config matching a certain pixelformat or native window type
added NATIVE_WINDOW_FORMAT attribute to android_native_window_t
The major things going on here:
- The MotionEvent API is now extended to included "pointer ID" information, for
applications to keep track of individual fingers as they move up and down.
PointerLocation has been updated to take advantage of this.
- The input system now has logic to generate MotionEvents with the new ID
information, synthesizing an identifier as new points are down and trying to
keep pointer ids consistent across events by looking at the distance between
the last and next set of pointers.
- We now support the new multitouch driver protocol, and will use that instead
of the old one if it is available. We do NOT use any finger id information
coming from the driver, but always synthesize pointer ids in user space.
(This is simply because we don't yet have a driver reporting this information
from which to base an implementation on.)
- Increase maximum number of fingers to 10. This code has only been used
with a driver that reports up to 2, so no idea how more will actually work.
- Oh and the input system can now detect and report physical DPAD devices.
there was several issues:
- when a surface was made non-current, the last frame wasn't shown and the buffer could stay locked
- when a surface was made current the 2nd time, it would not dequeue a new buffer
now, queue/dequeue are done when the surface is made current.
for this to work, a new query() hook had to be added on android_native_window_t, it allows to retrieve some attributes of a window (currently only width and height).
This will be used to avoid unnecessarily listening to data from sensors
that function as event devices.
Signed-off-by: Mike Lockwood <lockwood@android.com>
The kernel can now publish a property describing the layout of virtual
hardware buttons on the touchscreen. These outside of the display
area (outside of the absolute x and y controller range the driver
reports), and when the user presses on them a key event will be
generated rather than a touch event.
This also includes a number of tweaks to the absolute controller
processing to make things work better on the new screens. For
example, we now reject down events outside of the display area.
Still left to be done is the ability to cancel a key down event,
so the user can slide up from the virtual keys to the touch screen
without causing a virtual key to execute.
Merge commit 'c7396025e59524e7ef639fd86fc23123939ee91c'
* commit 'c7396025e59524e7ef639fd86fc23123939ee91c':
Return CAMERA_ERROR_SERVER_DIED to camera app when camera service dies (bug 1956726)
Merge commit '17a80081a42410f541a220ab7e6afc64fc6cc399'
* commit '17a80081a42410f541a220ab7e6afc64fc6cc399':
Pipe all the camera callbacks to Java to facilitate the addition
Merge commit 'a93466f5ca41c2ba6c3524c8d1edc2138bf753e3'
* commit 'a93466f5ca41c2ba6c3524c8d1edc2138bf753e3':
Cleanup header file. Disallow copy of Camera object by making copy
Merge commit '3d7b8d1aa6a362292f56defbe8fb2d5653f79282'
* commit '3d7b8d1aa6a362292f56defbe8fb2d5653f79282':
Use a ref-counted callback interface for Camera.
This allows the camera service to hang onto the callback interface
until all callbacks have been processed. This prevents problems
where pending callbacks in binder worker threads are processed
after the Java camera object and its associated native resources
have been released.
Bug 1884362
now, all destruction path, go through the purgatory which is emptied when ~ISurface is called, but we also make sure to remove the surface from the current list from there (in case a client forgot to request the destruction explicitely).
- return "const" objects for overloaded operators to disallow constructs like: (a+b) = c;
- don't return references to non-static members, it's not always safe.
- Point.cpp was empty, so get rid of it
This is the second half of bug 1837832. Modifies the camera client
and camera service to use the new binder interface. Removes the
old binder interface. There will be one more part to this change
to surface the undefined callbacks to the Java layer so that
partners can implement new features without having to touch the
stack.
This is the first step in a multi-step change to move from the old
specific callbacks to a generic callback. This will allow future
flexibility in the interface without requiring binder rewrites.
Bug 1837832
- Currently the lock/unlock path is naive and is done for each drawing operation (glDrawElements and glDrawArrays). this should be improved eventually.
- factor all the lock/unlock code in SurfaceBuffer.
- fixed "showupdate" so it works even when we don't have preserving eglSwapBuffers().
- improved the situation with the dirty-region and fixed a problem that caused GL apps to not update.
- make use of LightRefBase() where needed, instead of duplicating its implementation
- add LightRefBase::getStrongCount()
- renamed EGLNativeWindowSurface.cpp to FramebufferNativeWindow.cpp
- disabled copybits test, since it clashes with the new gralloc api
- Camera/Video will be fixed later when we rework the overlay apis
Add a factory method that creates a Camera object from a remote client
Next:
The changes in authordriver.cpp and android_camera_input.cpp will come.
and the constructor for Camera object will be removed.
The WindowManager side of Surface.java holds a SurfaceControl, while the client-side holds a Surface. When the client is in the system process, Surface.java holds both (which is a problem we'll try to fix later).
SurfaceControl is used for controling the geometry of the surface (for the WM), while Surface is used to access the buffers (for SF's clients).
SurfaceFlingerClient now uses the SurfaceID instead of Surface*.
Currently Surface still has the SurfaceControl API and is implemented by calling into SurfaceControl.
To deal with Java's lack of destructors and delayed garbage collection, we used to duplicate Surface.cpp objects in some case; this caused some issues because Surface is supposed to be reference-counted and unique.
