1. Tizen System / App Framework

2. Contents Overview (System & App FW) What is Ecore? System Framework
Application Framework

3. Overview System Framework App Framework
System managements and Device Abstractions
System condition management  Low memory, Low battery, process, CPU frequency handling
Device abstraction and control  display, mmc, earjack, GPS, haptic, etc.
System logging  dlog
Sensor management  sensor server and client library
App Framework
Application main loop
Inter-app communication and launching
Application Install & Uninstall
System event callback

4. What is Ecore? (Event main loop)
Ecore: EFL core library for application
“Operating system abstraction and integration”,
Event-driven main loop  Because GUI application is event-driven.
Many GUI Toolkit use event-driven main loop, ex) Glib
Frequently switch between IDLE / Event handling
save core resource
Can handle file descriptor and signal event
socket, pipe, vconf, IPC, etc.
Also able to use in non-GUI event driven program

5. System Framework

6. System FW Overview

7. System-server (framework/system/system-server)
System monitoring, managing, notifying
Low memory, low battery, USB connection, CPU frequency, Process, etc.
Use Ecore main_loop for event handling
main() (ss_main.c)
ecore_init(): initializing Ecore
system_main()
heynoti_init: initializing heynoti (notification library)
system_server_init(): initializing system server
sysnoti, queue, core, predefine_internal
lowmem
lowbat … etc.
notification to systemd
ecore_main_loop_begin(): start main loop of ecore

8. ss_synoti.c ss_sysnoti_init() synoti_cb()
ss_sysnoti_server_init(): open socket server for inter-process communication, and return file descriptor
register callback for the fd (/tmp/sn)
synoti_cb()
call ss_action_entry_call() to create event  ss_queue.c

9. ss_queue.c Task runqueue for system-server
Handle action from internal or pipe handler
ss_action_entry_add() / ss_action_entry_add_internal()
Specify action task and register to Eina list
ss_action_entry_call() / ss_action_entry_call_internal()
Insert action into run_queue (based on the msg of action_entry)
ss_core_action_run()  ss_core.c
ss_run_queue_run()
run the ‘run_function’ for each action_entry
Difference between internal or not
Internal: for internal source that will execute action.
non-internal: .so library will execute action using this ss_queue interface  new additional event can be served from system-server

10. ss_core.c Execute run queue event from pipe ss_core_init()
Create unnamed pipe, and register call back function for the pipe as core_pipe_cb
core_pipe_cb()
Register _ss_core_action_run as ‘run_function’ for run_queue
ss_core_action_run
send msg (action run) into pipe
_ss_core_action_run
Call predefine_action of run_queue_entry

11. ss_predefine.c Register predefine function for specific status
ss_action_entry_add_internal
Example: lowmem 

12. ss_lowmem_handler.c Low memory handler
Check memory status from sysfs in kernel (ecore)
Alert low memory situation into appcore (vconf)
Perform proper event according to memory status
Normal
Only change vconf information
Low
Remove all of shared memory with zero reference count
Alert lowmem information using heynoti
Change vconf information
Critical (OOM)
Same behavior as Low + Kill victim process
Victim process is chosen from Kernel

13. Others
Other system events (Low battery, USB connection, Device change, MMC device) are also similar as low memory handler.
Handle system-level event for device
e.g.
mount, and unmount, format event will be handled from system-server
Storage I/O will not be handled from system-server

14. Inter-process communication
Various Inter-process communication
heynoti
ss_synoti
socket
pipe
vconf
dbus

15. heynoti (framework/appfw/heynoti)
light-weight notification library
using inotify mechanism
alert filesystem event
simple mechanism
make inotify fd for specific name
subscribe for specific name
sender publishes notification
App notifies and handles notification

16. ss_sysnoti Send event into system-server libslp_sysman
Enable run_queue (in system-server) to handle the event from proper handler
Using socket communication
libslp_sysman
Helper library to notify the message to system-server
sysnoti.c
synoti_send(msg): send socket msg into /tmp/sn
sysman_call_predef_action(): request into system-server to run predefined function for the event

17. vconf (framework/appfw/vconf)
Key-value fair + inotify
Various functionality than heynoti
Store system configuration using SQLite (libsqlfs)
Able to communicate between inter-process using inotify

18. dbus Inter-process communication mechanism using socket
Using Dbus daemon, App (or process) can send message into other App (or process)
Access control using SMACK

19. Device manager Device manager library for device control
LCD, display control (brightness, tone)
battery monitoring
haptic event access

20. libdevicenode
Library that manages device node for each devices in system
Not only real device, sysfs node also can be managed.
Add device node into device list, and register the callback function for get and set request  OAL Interface Function
Device_get_property
Get device information (through corresponding OAL interface function)
Device_set_property
Set device status (or command) (with OAL interface function)
OAL Interface
libslp_devman_plugin.so
System developer should make OAL Interface library for each system devices

21. Sensor Framework Types of Sensors
Tizen supports individual plugin frameworks for these sensors:
Accelerometer sensor
Gyroscope sensor
Proximity sensor
Motion sensor
Geomagnetic sensor
Light sensor

22. Sensor details Accelerometer sensor Gyroscope sensor Proximity sensor
The accelerometer sensor is used to measure the acceleration of the device. The three dimensional coordinate system is used to illustrate the direction of the acceleration. When a phone is moving along an axis, the acceleration is positive if it moves in a positive direction.
Gyroscope sensor
A gyroscope is a device used primarily for navigation and measurement of angular velocity. Gyroscopes measure how quickly an object rotates. This rate of rotation can be measured along any of the three axes X, Y, and Z.
Proximity sensor
A proximity sensor can detect the presence of nearby objects without any physical contact. That is, it indicates if the device is close or not close to the user.
Motion sensor
A motion sensor is a virtual sensor that uses the accelerometer and gyroscope sensors. Motion sensor detects snap, panning, tilt, shake, overturn, and double tap event.
Geomagnetic sensor
A geomagnetic sensor indicates the strength of the geomagnetic flux density in the X, Y, and Z axes. This sensor is used to find the orientation of a body, which is a description of how it is aligned to the space it is in.
Light sensor
A light sensor measures the amount of light that it receives or the surrounding light conditions. The ambient light state is measured as a step value, where 0 is very dark and 10 is bright sunlight.

23. Sensor Framework details
Components of Sensor Framework
The Sensor framework provides a sensor server for creating plugins and a medium through which the client applications are connected to the sensor hardware to exchange data. The sensor plugins retrieve data from sensor hardware and enable the client applications to use the data for specific requirements.
Sensor Library
The application that wants to access the sensor service should communicate with the daemon through the sensor API library. An API library allows the application to access the sensor service. As shown in the below diagram, applications/middleware frameworks can have the sensor-framework client library in the process context.
Sensor Server
The sensor server is a daemon which communicates uniquely to sensor drivers in the system and dispatches sensor data to the application. The sensor server takes care of interacting with the sensor driver in hardware initialization, driver configuration, and data fetching, to manage all sensors on the platform.
Type of plugins in sensor framework
Sensor Plugin
Sensor plugins takes care of interacting with the sensor driver. Plug-ins process data from sensor drivers and communicate it to the sensor server.
Processor
Active component (it has a thread) that processes data or makes events from a filter or from sensor data.
Filter
Passive component that converts sensor raw data to other types of data
Sensor
Passive component that gets raw data from the kernel node

24. App Framework

25. App Framework Overview

26. Tizen Core Application Types

27. Appcore
Appcore is the application core handling various important events each of which application should be ware of.
Using appcore, developers can
Manage application life-cycle
Create, Reset, Pause, Resume, Terminate
Handle System Events
Low Memory
Low Battery
Screen orientation Change
Language & Region Change

28. Appcore Internal callback

29. Using appcore Include appcore_common.h or appcore_efl.h
fill appcore_ops for proper function pointers
call appcore_efl_main when using EFL

30. Application Life Cycle: State and Transitions

31. Tizen GUI App Structure

32. Application Utility Library: AUL
Application Utility Library (AUL) provides the following features
Launching/terminating applications
Providing running application information
AUL consists of the following sub-components:
AUL library: Sending/receiving requests for launching and terminating
AUL daemon (a.k.a. launch pad): Handling the requests

33. AUL Daemon (launchpad)
Open socket file
wait for recv() at __launchpad_main_loop

34. AUL Overall ARchitecture

35. Application Data Exchange
The actual Application Data Exchange (ADE) occurs as an argument between the caller and callee, using a bundle.
Bundle is a type of dictionary abstract data, in which information is stored as key-value pairs.
Bundle contains information regarding the state the app should prepare.

36. AUL: Launch In case of single-instance application
If app is not running, launch application
If app is already running, send reset event to the running application
In case of multi-instance application
launch an app

37. App Service (high-level App Launcher)
App service exposes general service terms, such as view, create, call, and so forth, to developers in case of launching an application with a specific feature
More desirable asking image view service without knowing what image viewer apps are available.
Each service can be determined by given operation, URI and MIME type.
Operation: expected action for the request (e.g., view, edit, call, send..)
URI: URI information for requested operation (e.g., file://...)
MIME type: MIME type information for requested operation (e.g., image/jpeg)
Data: Extra data to launched service application(contained in a bundle packet)

38. App Service Overall Flow

39. App Service Request

40. Package Manager
Package manager is responsible for installing, upgrading and uninstalling of applications and storing their information.
Expandable structure to support various types of applications
Designated installation modules can be added to the manager
Web app, native app, java app, and so forth

41. Application Information Library: AIL
AIL is the library providing functionalities to execute application information-related tasks.
AIL provides the following features
Adding, updating and removing application information.
Managing application's information –application name, type, icon path, exec path, etc.
Retrieving an application list which meets a given filter.

42. App Use History: RUA
Recently Used Application (RUA) logs application use history.
When an application is launched, launch pad updates the history and task manager can either get or clear the history.
RUA also provides below information regarding launching:
package name
launch time
application path
application launch argument

43. References “An Overview of Tizen Application Core Framework”, TDC 2012
“Tizen Core APIs: A Core Framework Layer to Build In-House Applications”, TDC 2014
Tizen wiki,