build/envsetup.sh 腳本主體部分
看源代碼之前需要了解代碼分佈和結構,分析Makefile應該是最好的方法。在Blog記錄之以備以後查看,也供有興趣朋友參考。
在編譯donut之前,需要運行
cd ~/mydroid
. build/envsetup.sh
lunch aosp_dream_us-eng
make
build/envsetup.sh 是編譯android的入口。該shell腳本定義了一些函數,並設定了編譯的環境變量。
lunch aosp_dream_us-eng 配置用戶需要編譯的目標產品(target product)和變體(variant)。
aosp_dream_us-eng 字符串包含了target product 和variant,它們用減號-隔開,aosp_dream_us是target product,eng是variant。
variant 有三種選擇user userdebug eng,可以從字面上看出其意義,但具體的差別還不是特別清楚,待後面分析之。
lunch 的入口是讓用戶指定或者選擇需要編譯的target product 和 variant,出口是設定編譯相關的環境變量。
build/envsetup.sh 定義了很多函數,並且執行的腳本很分散,因此下面將所有的函數都刪除掉了,剩餘下腳本的主體,便於代碼分析和走讀。
該主體主要做的事情是:
1. 首先腳本設定了兩個缺省的target product,一個是generic-eng,一個是simulator
2. 運行所有vendor下的 vendorsetup.sh文件,在google官方的 donut源代碼中,爲vendor/aosp/vendorsetup.sh,內容如下:
add_lunch_combo aosp_emulator_us-eng
add_lunch_combo aosp_emulator_eu-eng
add_lunch_combo aosp_dream_us-userdebug
add_lunch_combo aosp_dream_eu-userdebug
add_lunch_combo aosp_dream_us-eng
add_lunch_combo aosp_dream_eu-eng
add_lunch_combo aosp_sapphire_us-userdebug
add_lunch_combo aosp_sapphire_eu-userdebug
add_lunch_combo aosp_sapphire_us-eng
add_lunch_combo aosp_sapphire_eu-eng
可以看出,又添加了一些 和 aosp 相關的 target product 和 variant。
下面是腳本主體,用藍色添加了一下注釋,便於閱讀:
# 定義了 variant的字符範圍
VARIANT_CHOICES=(user userdebug eng)
# 如果是Linux環境,定義了幾個和simulator相關的函數
case `uname -s` in
Linux)
function choosesim()
{
echo "Build for the simulator or the device?"
echo " 1. Device"
echo " 2. Simulator"
echo
export TARGET_SIMULATOR=
local ANSWER
while [ -z $TARGET_SIMULATOR ]
do
echo -n "Which would you like? [1] "
if [ -z "$1" ] ; then
read ANSWER
else
echo $1
ANSWER=$1
fi
case $ANSWER in
"")
export TARGET_SIMULATOR=false
;;
1)
export TARGET_SIMULATOR=false
;;
Device)
export TARGET_SIMULATOR=false
;;
2)
export TARGET_SIMULATOR=true
;;
Simulator)
export TARGET_SIMULATOR=true
;;
*)
echo
echo "I didn't understand your response. Please try again."
echo
;;
esac
if [ -n "$1" ] ; then
break
fi
done
set_stuff_for_environment
}
;;
*)
function choosesim()
{
echo "Only device builds are supported for" `uname -s`
echo " Forcing TARGET_SIMULATOR=false"
echo
if [ -z "$1" ]
then
echo -n "Press enter: "
read
fi
export TARGET_SIMULATOR=false
set_stuff_for_environment
}
;;
esac
# 首先將 LUNCH_MENU_CHOICES 變量消除
# Clear this variable. It will be built up again when the vendorsetup.sh
# files are included at the end of this file.
unset LUNCH_MENU_CHOICES
# 當前 LUNCH_MENU_CHOICES = generic-eng
# add the default one here
add_lunch_combo generic-eng
# 當前 LUNCH_MENU_CHOICES = generic-eng simulator
# if we're on linux, add the simulator. There is a special case
# in lunch to deal with the simulator
if [ "$(uname)" = "Linux" ] ; then
add_lunch_combo simulator
fi
# 這裏是MAC OS的環境,不考慮
case `uname -s` in
Darwin)
function mgrep()
{
find -E . -type f -iregex '.*/(Makefile|Makefile\..*|.*\.make|.*\.mak|.*\.mk)' -print0 | xargs -0 grep --color -n "$@"
}
function treegrep()
{
find -E . -type f -iregex '.*\.(c|h|cpp|S|java|xml)' -print0 | xargs -0 grep --color -n -i "$@"
}
;;
*)
function mgrep()
{
find . -regextype posix-egrep -iregex '(.*\/Makefile|.*\/Makefile\..*|.*\.make|.*\.mak|.*\.mk)' -type f -print0 | xargs -0 grep --color -n "$@"
}
function treegrep()
{
find . -regextype posix-egrep -iregex '.*\.(c|h|cpp|S|java|xml)' -type f -print0 | xargs -0 grep --color -n -i "$@"
}
;;
esac
# 設定當前shell環境的數組下標從0開始還是1開始,並記錄在 _arrayoffset
# determine whether arrays are zero-based (bash) or one-based (zsh)
_xarray=(a b c)
if [ -z "${_xarray[${#_xarray[@]}]}" ]
then
_arrayoffset=1
else
_arrayoffset=0
fi
unset _xarray
# 運行所有vendor下的 vendorsetup.sh文件
#存在vendor/aosp/vendorsetup.sh
當前 LUNCH_MENU_CHOICES = generic-eng simulator aosp_emulator_us-eng aosp_emulator_eu-eng aosp_dream_us-userdebug aosp_dream_eu-userdebug aosp_dream_us-eng aosp_dream_eu-eng aosp_sapphire_us-userdebug aosp_sapphire_eu-userdebug aosp_sapphire_us-eng aosp_sapphire_eu-eng
# Execute the contents of any vendorsetup.sh files we can find.
for f in `/bin/ls vendor/*/vendorsetup.sh vendor/*/build/vendorsetup.sh 2> /dev/null`
do
echo "including $f"
. $f
done
unset f
明天接下來看 lunch()函數
build/envsetup.sh 腳本分析(lunch函數)
lunch函數提供了一個菜單,讓開發人員選擇需要編譯的目標產品(target product)和變體(variant),並做一些檢查,設置環境變量,並打印出主要的環境變量。
直接運行lunch(必須先運行 build/envsetup.sh,讓lunch函數駐留到環境變量中)
ning@ning-desktop:~/donut-compare/mydroid$ lunch
You're building on Linux
generic-eng simulator aosp_emulator_us-eng aosp_emulator_eu-eng aosp_dream_us-userdebug aosp_dream_eu-userdebug aosp_dream_us-eng aosp_dream_eu-eng aosp_sapphire_us-userdebug aosp_sapphire_eu-userdebug aosp_sapphire_us-eng aosp_sapphire_eu-eng
Lunch menu... pick a combo:
1. generic-eng
2. simulator
3. aosp_emulator_us-eng
4. aosp_emulator_eu-eng
5. aosp_dream_us-userdebug
6. aosp_dream_eu-userdebug
7. aosp_dream_us-eng
8. aosp_dream_eu-eng
9. aosp_sapphire_us-userdebug
10. aosp_sapphire_eu-userdebug
11. aosp_sapphire_us-eng
12. aosp_sapphire_eu-eng
Which would you like? [generic-eng] 7
============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=1.6
TARGET_PRODUCT=aosp_dream_us
TARGET_BUILD_VARIANT=eng
TARGET_SIMULATOR=false
TARGET_BUILD_TYPE=release
TARGET_ARCH=arm
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=Donut
============================================
用戶也可以直接輸入參數,不使用菜單
ning@ning-desktop:~/donut-compare/mydroid$ lunch aosp_dream_us-eng
============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=1.6
TARGET_PRODUCT=aosp_dream_us
TARGET_BUILD_VARIANT=eng
TARGET_SIMULATOR=false
TARGET_BUILD_TYPE=release
TARGET_ARCH=arm
HOST_ARCH=x86
HOST_OS=linux
HOST_BUILD_TYPE=release
BUILD_ID=Donut
============================================
下面是lunch函數源代碼,用藍色添加了一下注釋,便於閱讀:
function lunch()
{
local answer
if [ "$1" ] ; then
# lunch後面直接帶參數
answer=$1
else
# lunch後面不帶參數,則打印處所有的target product和variant菜單提供用戶選擇
print_lunch_menu
echo -n "Which would you like? [generic-eng] "
read answer
fi
local selection=
if [ -z "$answer" ]
then
# 如果用戶在菜單中沒有選擇,直接回車,則爲系統缺省的generic-eng
selection=generic-eng
elif [ "$answer" = "simulator" ]
then
# 如果是模擬器
selection=simulator
elif (echo -n $answer | grep -q -e "^[0-9][0-9]*$")
then
# 如果answer是選擇菜單的數字,則獲取該數字對應的字符串
if [ $answer -le ${#LUNCH_MENU_CHOICES[@]} ]
then
selection=${LUNCH_MENU_CHOICES[$(($answer-$_arrayoffset))]}
fi
# 如果 answer字符串匹配 *-*模式(*的開頭不能爲-)
elif (echo -n $answer | grep -q -e "^[^\-][^\-]*-[^\-][^\-]*$")
then
selection=$answer
fi
if [ -z "$selection" ]
then
echo
echo "Invalid lunch combo: $answer"
return 1
fi
# special case the simulator
if [ "$selection" = "simulator" ]
then
# 模擬器模式
export TARGET_PRODUCT=sim
export TARGET_BUILD_VARIANT=eng
export TARGET_SIMULATOR=true
export TARGET_BUILD_TYPE=debug
else
# 將 product-variant模式種的product分離出來
local product=$(echo -n $selection | sed -e "s/-.*$//")
# 檢查之,調用關係 check_product()->get_build_var()->build/core/config.mk比較羅嗦,不展開了
check_product $product
if [ $? -ne 0 ]
then
echo
echo "** Don't have a product spec for: '$product'"
echo "** Do you have the right repo manifest?"
product=
fi
# 將 product-variant模式種的variant分離出來
local variant=$(echo -n $selection | sed -e "s/^[^\-]*-//")
# 檢查之,看看是否在 (user userdebug eng) 範圍內
check_variant $variant
if [ $? -ne 0 ]
then
echo
echo "** Invalid variant: '$variant'"
echo "** Must be one of ${VARIANT_CHOICES[@]}"
variant=
fi
if [ -z "$product" -o -z "$variant" ]
then
echo
return 1
fi
export TARGET_PRODUCT=$product
export TARGET_BUILD_VARIANT=$variant
export TARGET_SIMULATOR=false
export TARGET_BUILD_TYPE=release
fi # !simulator
echo
# 設置到環境變量,比較多,不再一一列出,最 簡單的方法 set >env.txt 可獲得
set_stuff_for_environment
# 打印一些主要的變量, 調用關係 printconfig()->get_build_var()->build/core/config.mk->build/core/envsetup.mk 比較羅嗦,不展開了
printconfig
}
原文鏈接:
http://www.lupaworld.com/home.php?mod=space&uid=131820&do=blog&id=149463