android lichee编译脚本解析
#编译流程
#lichee 目录下
./build.sh -p sun7i_android -k 3.4#build.sh 解析
#!/bin/bash
set -e #"Exit immediately if a simple command exits with a non-zero status."
#也就是说，在"set -e"之后出现的代码，一旦出现了返回值非零，整个脚本就会立即退出
buildroot/scripts/mkcommon.sh $@ #$@ 为参数 -p sun7i_android -k 3.4
#mkcommon.sh
#!/bin/bash
#
# scripts/mkcommon.sh
# (c) Copyright 2013
# Allwinner Technology Co., Ltd. #编译all
function mklichee()
{
mksetting #打印编译信息
mk_info "build lichee ..." #显示编译，带颜色显示
#编译交叉编译工具 ----这里就不分析了
#编译内核
#编译uboot
#编译文件系统
mkbr && mkkernel && mkuboot && mkrootfs
[ $? -ne 0 ] && return 1
mk_info "build lichee OK."
}编译内核所做的事情：
#，根据平台配置，编译内核 ，把编译好的内核，模块 以及.config 拷到了output 目录下
#把output 目录下的所有内容，LICHEE_PLAT_OUT
#也就是 …/lichee/out/android/common
编译uboot 所做的事情
# 根据平台选择编译脚本 —–其实这一步没起作用，最终用的build.sh
# 先make distclean ，再根据芯片 sun7i进行编译，生成u-boot.bin
#所有这里可以选择把distclean 去掉，节约编译时间
# 把u-boot.bin拷贝到了 lichee/out/android/common 目录下
编译rootfs所做的事情：
#根据linux 或者dragonboard 做相应的操作
# 而这 do nothing ,skip
//———————————-other ————————————
function mkrootfs()
{
mk_info "build rootfs ..."
if [ ${LICHEE_PLATFORM} = "linux" ] ; then
make O=${LICHEE_BR_OUT} -C ${LICHEE_BR_DIR} target-generic-getty-busybox
[ $? -ne 0 ] && mk_error "build rootfs Failed" && return 1
make O=${LICHEE_BR_OUT} -C ${LICHEE_BR_DIR} target-finalize
[ $? -ne 0 ] && mk_error "build rootfs Failed" && return 1
make O=${LICHEE_BR_OUT} -C ${LICHEE_BR_DIR} LICHEE_GEN_ROOTFS=y rootfs-ext4
[ $? -ne 0 ] && mk_error "build rootfs Failed" && return 1
cp ${LICHEE_BR_OUT}/images/rootfs.ext4 ${LICHEE_PLAT_OUT}
elif [ ${LICHEE_PLATFORM} = "dragonboard" ] ; then
echo "Regenerating dragonboard Rootfs..."
(cd ${LICHEE_BR_DIR}/target/dragonboard; \
if [ ! -d "./rootfs" ]; then \
echo "extract dragonboard rootfs.tar.gz"; \
tar zxf rootfs.tar.gz; \
fi \
)
mkdir -p ${LICHEE_BR_DIR}/target/dragonboard/rootfs/lib/modules
rm -rf ${LICHEE_BR_DIR}/target/dragonboard/rootfs/lib/modules/*
cp -rf ${LICHEE_KERN_DIR}/output/lib/modules/* ${LICHEE_BR_DIR}/target/dragonboard/rootfs/lib/modules/
(cd ${LICHEE_BR_DIR}/target/dragonboard; ./build.sh)
cp ${LICHEE_BR_DIR}/target/dragonboard/rootfs.ext4 ${LICHEE_PLAT_OUT}
else
mk_info "skip make rootfs for ${LICHEE_PLATFORM}"
fi
mk_info "build rootfs OK."
}# return true if used default config
function check_uboot_defconf()
{
local defconf
local ret=1
defconf="${LICHEE_CHIP}_${LICHEE_PLATFORM}_${LICHEE_BOARD}"
#编译 sun7i_android
#这里少了一个.sh,脚本有问题:sun7i_android.sh
if [ ! -f ${LICHEE_UBOOT_DIR}/include/configs/${defconf} ] ; then
ret=0
defconf="${LICHEE_CHIP}" #这里少了一个.sh 应该为：sun7i.sh
fi
export LICHEE_UBOOT_DEFCONF=${defconf}
return ${ret}
}
function mkuboot()
{
mk_info "build u-boot ..."
local build_script
if check_uboot_defconf ; then #查看配置是是否存在，指定编译脚本
build_script="build.sh" #运行此编译脚本
else
build_script="build_${LICHEE_CHIP}_${LICHEE_PLATFORM}_${LICHEE_BOARD}.sh"
fi
prepare_toolchain
//运行编译脚本
(cd ${LICHEE_UBOOT_DIR} && [ -x ${build_script} ] && ./${build_script})
[ $? -ne 0 ] && mk_error "build u-boot Failed" && return 1
mk_info "build u-boot OK."
}
#关键的编译函数：
function build_uboot()
{
case "$1" in
clean)
make distclean CROSS_COMPILE=arm-linux-gnueabi-
;;
*)
make distclean CROSS_COMPILE=arm-linux-gnueabi- #清楚所有配置
make -j${jobs} ${LICHEE_CHIP} CROSS_COMPILE=arm-linux-gnueabi-
#根据芯片 编译 这里是sun7i
[ $? -ne 0 ] && exit 1
#拷贝u-boot.bin 到输出目录
cp -f u-boot.bin ../out/${LICHEE_PLATFORM}/common/
;;
esac
}
function mksetting() #打印要编译的信息
{
printf "\n"
printf "mkscript current setting:\n"
printf " Chip: ${LICHEE_CHIP}\n"
printf " Platform: ${LICHEE_PLATFORM}\n"
printf " Board: ${LICHEE_BOARD}\n"
printf " Output Dir: ${LICHEE_PLAT_OUT}\n"
printf "\n"
}
编译内核函数
function mkkernel()
{
mk_info "build kernel ..."
local build_script
if check_kern_defconf ; then #检查设置，编译配置文件
if [ ${LICHEE_PLATFORM} = "linux" ] ; then
build_script="scripts/build_${LICHEE_CHIP}.sh"
else
build_script="scripts/build_${LICHEE_CHIP}_${LICHEE_PLATFORM}.sh"
#指定编译脚本 scripts/build_sun7i_android.sh
fi
else
build_script="scripts/build_${LICHEE_CHIP}_${LICHEE_PLATFORM}_${LICHEE_BOARD}.sh"
fi
prepare_toolchain #准备交叉编译工具，就是导出环境变量
#lichee/out/android/common/buildroot/external-toolchain
# mark kernel .config belong to which platform
local config_mark="${LICHEE_KERN_DIR}/.config.mark" #标记编译平台 android
if [ -f ${config_mark} ] ; then
if ! grep -q "${LICHEE_PLATFORM}" ${config_mark} ; then
mk_info "clean last time build for different platform"
(cd ${LICHEE_KERN_DIR} && [ -x ${build_script} ] && ./${build_script} "clean")
echo "${LICHEE_PLATFORM}" > ${config_mark}
fi
else
echo "${LICHEE_PLATFORM}" > ${config_mark}
fi
#进入内核目录 ，检查编译脚本是否可执行，执行该脚本
#./scripts/build_sun7i_android.sh
(cd ${LICHEE_KERN_DIR} && [ -x ${build_script} ] && ./${build_script})
[ $? -ne 0 ] && mk_error "build kernel Failed" && return 1
mk_info "build kernel OK."
}
脚本#build_sun7i_android.sh 如下
#!/bin/bash
#
# scripts/build_sun7i_android.h
#
# (c) Copyright 2013
# Allwinner Technology Co., Ltd. function init_chips()
{
local chip=$1 #传进来的参数：sun7i
local cnt=0
local ret=1
for chipdir in ${LICHEE_TOOLS_DIR}/pack/chips/* ; do
chips[$cnt]=`basename $chipdir`
if [ ${chips[$cnt]} = ${chip} ] ; then #检测是否有该芯片的目录
ret=0
export LICHEE_CHIP=${chip}
fi
((cnt+=1))
done
return ${ret}
}
function init_platforms()
{
local chip=$1 #传进来的芯片 sun7i
local platform=$2 #传进来的平台 android
local cnt=0
local ret=1
for platdir in ${LICHEE_TOOLS_DIR}/pack/chips/${chip}/configs/* ; do
platforms[$cnt]=`basename $platdir`
if [ ${platforms[$cnt]} = ${platform} ] ; then #检查是否支持该平台打包
ret=0
export LICHEE_PLATFORM=${platform}
fi
((cnt+=1))
done
return ${ret}
}
# output to out///common directory only when
# both buildroot and kernel use default config file.
function init_outdir()
{
if check_br_defconf && check_kern_defconf ; then
#check_kern_defconf 检查配置是否存在
export LICHEE_PLAT_OUT="${LICHEE_OUT_DIR}/${LICHEE_PLATFORM}/common"
#导出plat 目录 .../lichee/out/android/common
export LICHEE_BR_OUT="${LICHEE_PLAT_OUT}/buildroot"
#导出 br 目录 ../lichee/out/android/common/buildroot
else
export LICHEE_PLAT_OUT="${LICHEE_OUT_DIR}/${LICHEE_PLATFORM}/${LICHEE_BOARD}"
export LICHEE_BR_OUT="${LICHEE_PLAT_OUT}/buildroot"
fi
mkdir -p ${LICHEE_BR_OUT} #创建目录
}