Building Android system

Move to android root directory.

Set up buildenv as below

dokyun@android$
dokyun@android$ source ./build/envsetup.sh
including device/samsung/maguro/vendorsetup.sh
including device/samsung/tuna/vendorsetup.sh
including device/ti/panda/vendorsetup.sh
including sdk/bash_completion/adb.bash
dokyun@android$

Set up build target as below
$ lunch [Build-name]-[build type]

build name is target device name such as panda or maguro
build type is build configuration such as debugging option or limitation.

currently I do not have special target , select emulator for build-name , eng for build-type

dokyun@android$ lunch full-eng
============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=4.0.1
TARGET_PRODUCT=full
TARGET_BUILD_VARIANT=eng
TARGET_BUILD_TYPE=release
TARGET_BUILD_APPS=
TARGET_ARCH=arm
TARGET_ARCH_VARIANT=armv7-a
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=ITL41D
============================================
dokyun@android$

then build

dokyun@android$ make -j4

It can takes more than 1 hour at first build , it depends on your build system

You can also select manually the target board as like below

dokyun@android$ lunch
You're building on Linux
Lunch menu... pick a combo:
     1. full-eng
     2. full_x86-eng
     3. vbox_x86-eng
     4. full_maguro-userdebug
     5. full_tuna-userdebug
     6. full_panda-eng
Which would you like? [full-eng] 6
============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=4.0.1
TARGET_PRODUCT=full_panda
TARGET_BUILD_VARIANT=eng
TARGET_BUILD_TYPE=release
TARGET_BUILD_APPS=
TARGET_ARCH=arm
TARGET_ARCH_VARIANT=armv7-a-neon
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=ITL41D
============================================
dokyun@android$ make -j4

Adroid Source Code Download

• Installing repo

Repo is a tool that makes it easier to work with Git in the context of Android.

$ mkdir ~/bin
$ PATH=~/bin:$PATH

$ curl https://dl-ssl.google.com/dl/googlesource/git-repo/repo > ~/bin/repo
$ chmod a+x ~/bin/repo

As you can see , it just get repository related script form https://dl-ssl.google.com/dl/googlesource/git-repo/repo and make excutable

• Initializing a Repo client

First make working directory, in my case

$ mkdir ~/android
$ cd ~/android

then initialize repository.

$ repo init -u https://android.googlesource.com/platform/manifest

It shows below error at first time

-----------------------------------------------------------------------
*** Please tell me who you are.
Run
  git config --global user.email "you@example.com"
  git config --global user.name "Your Name"
to set your account's default identity.
Omit --global to set the identity only in this repository.
fatal: empty ident  <dokyun@redbomb-server.(none)> not allowed-----------------------------------------------------------------------

as you can see on the error message, type your email and name

$ git config --global user.email "dokyun.beon@gmail.com"
$ git config --global user.name "dokyun beon"

then excute again
$ repo init -u https://android.googlesource.com/platform/manifest
$ repo init -u https://android.googlesource.com/platform/manifest -b android-4.0.1_r1
$ repo sync

as you can see, down load is done
-----------------------------------------------------------------------
dokyun@android$ ls
Makefile  bionic    build  dalvik       device  external    hardware  ndk       prebuilt  system
abi       bootable  cts    development  docs    frameworks  libcore   packages  sdkdokyun@android$
-----------------------------------------------------------------------

refer to official home more detail.

http://source.android.com/source/downloading.html

exporting kernel headers- headers_install

• command for exporting kernel headers in user space

make headers_install ARCH=arm INSTALL_HDR_PATH=/usr/include

• how to include headers for headers_install

Add headers in Kbuild under {kernel_source_dir}/include/
header-y += {header_file_name.h}

For more detail, refer to headers_install.txt