rom compiling guide

build_rom

# not an actual script but you could convert it though
# links are for lenovo vibe P1m nougat roms for other devices and android version these may or ma not be different

# selecting the os
# you could use any varient of ubuntu but i suggest to use on above 16.xx

#update what you have
sudo apt-get update && sudo apt-get upgrade

# install all the tools
git clone https://github.com/akhilnarang/scripts.git scripts && cd scripts
bash setup/android_build_env.sh
bash setup/install_android_sdk.bash
bash setup/setup_android_sdk_packages.bash

# make a new dir for syncing the source
mkdir MyRom && cd MyRom

# configure your github
git config --global user.name "your user name"
git config --global user.mail "your mail id"

# i'm going to compile lineage os
repo init -u git://github.com/LineageOS/android.git -b cm-14.1
repo sync # this will start the sync and will take sometime

# time to clone the device sources
git clone https://github.com/darklord4822/android_device_lenovo_P1m.git -b cm-14.1 device/lenovo/P1m
git clone https://github.com/z3r0c00l-2k/android_vendor_lenovo_P1m.git -b n vendor/lenovo/P1m
git clone https://github.com/darklord4822/android_kernel_lenovo_P1m.git -b master kernel/lenovo/P1m

# apply pathes 
# this is device specific , if your device doesn't require patches , just skip this
cd device/lenovo/P1m/patches
bash apply-patches.sh
cd ../../../../
# if some patches didn't get applied properly manually patch them

# setup cache
export CCACHE_DIR=./.ccache
ccache -C
export USE_CCACHE=1
export CCACHE_COMPRESS=1
prebuilts/misc/linux-x86/ccache/ccache -M 50G

# start compiling 
source build/envsetup.sh && lunch lineage_P1m-userdebug && brunch lineage_P1m -j$(nproc --all)

# if you get an error google it and fix it

# to compile for a different rom you have to prepare device tree according to that rom
# there is no universal way of doing this
# simplest way to do this is by looking at the official device trees for devices which have that rom
# for some roms like rr , there is no need for such changes cm or lineage tree can be use for rr