Mozilla's Boot to Gecko (B2G) is an open source mobile operating system based on Linux and Mozilla's Gecko technology. It allows all user software to be built as web apps using HTML5, CSS, and JavaScript. The main components of B2G are Gaia for the user interface, Gecko for running web apps, and Gonk which includes the Linux kernel and hardware abstraction layer. Gaia is entirely web-based, while Gecko implements web standards and exposes device APIs. B2G can run on the Samsung Galaxy S2 and Nexus S, as well as emulators like QEMU.

1. Mozilla Boot to Gecko
平台技術概況
陳鵬宇 (float)<a13524000@gmail.com>
May 19, 2012/MOSUT

2. 什麼是 Boot to Gecko(B2G)
● Mozilla's open source mobile operating
system based on Linux and Mozilla's
Gecko technology.
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3. 概念
● The idea is essentially to have all user-
accessible software running on the
phone be a Web app that uses advanced
HTML5 techniques and device APIs to
access the phone's hardware directly via
JavaScript.
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4. 系統介紹
● Gaia
● Gecko
● Gonk
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5. Gaia
● The user interface of b2g. Everything
drawn to screen after b2g starts up is
some part of Gaia. Gaia implements a
lock screen, home screen, telephone
dialer, text-messaging application,
camera app, ... and many more.
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6. Gaia
● Gaia is written entirely in HTML, CSS,
and JavaScript. Its only interface to the
underlying operating system is through
Open Web APIs, which are implemented
by Gecko. Gaia works well when run on
top of b2g; however, since it only uses
standard web APIs, it works on other
OSes and in other web browsers.
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7. Gaia
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8. 可能會有人想問
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9. 可能會有人想問
為什麼只有一張圖？
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10. 因為 ... 改版了
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11. MOSUT 11

12. Gecko
● The "application runtime" of b2g. At a
high level, Gecko implements the open
standards for HTML, CSS, and JS and
makes those interfaces run well on all
the OSes that Gecko supports.
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13. Gonk
● The lower-level "operating system" of
b2g. Gonk consists of a linux kernel and
userspace hardware abstraction layer
(HAL).
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14. …......
Gaia Web app
Gecko
b2g
Gonk
kernel
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15. 比較
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16. Boot
Boot Loader Kernel init
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17. Userspace process architecture
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18. Gecko: Processing input events
● input-device drivers
● Gonk app shell
● EventHub
● DOM
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19. Gecko: Graphics
● At the very lowest level, Gecko uses
OpenGL ES 2.0 to draw to a glcontext
that wraps the hardware framebuffers.
● Gecko draws directly to VRAM.
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20. MOSUT 20

21. Web app
● Web apps are apps built using standard
Web technologies.
● manifest.json
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22. manifest.json
https://developer.mozilla.org/en/Apps/Manifest
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23. Intsall app
● navigator.mozApps.install(manifestURL)
or
● Put app in gaia/apps/
● make install-gaia
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24. Marketplace
https://marketplace.mozilla.org/
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25. Demo
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26. MOSUT 26

27. Run B2G
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28. Firefox Nightly + gaia
http://alivedise.github.com/blog/2012/05/05/gaia/
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29. Emulator
● QEMU Emulator
http://www.figuiere.net/hub/blog/?2012/03/13/818-building-b2g-on-fedora-field-notes
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30. Device
● Samsung Galaxy S2
● Samsung Nexus S
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31. Reference
● https://developer.mozilla.org/en/Mozilla/Boot_to_Gecko
● https://wiki.mozilla.org/B2G/Architecture
● http://pydoing.blogspot.com/2010/12/javascript-example.html
● http://mozlinks-zh.blogspot.com/2012/05/gaia-mozilla-b2g.html
● http://www.slideshare.net/robhawkes/mdn-hackday-london-boot-
to-gecko-the-future-of-mobile
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32. Thank you
Question?
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