README-system-dir

/system/ directory build instructions
=====================================

The /system/ directory available on the skipjack platform and provided in
prebuilt form by android:skipjack-o.bb is a tricky mix of an original WearOS
/system and some recompiled parts. This is due to the half-closed nature of
WearOS. This file explains you how to rebuild manually your own /system dir.

We first need to adb pull a /system directory from a living WearOS 8.0.0
installation:
  adb pull /system/ system
  cd system/
  rm -rf app/ fake-libs fonts/ framework/ media/ priv-app/ usr/ xbin/ manifest.xml etc/init vendor/etc/init
  cp system/vendor/lib/hw/sensors.cywee.so system/lib/hw/sensors.default.so

This installation wouldn't be enough because libhybris needs a patched bionic
Thankfully, bionic is open-source so we can download AOSP and build it. (This
may take a while)
  ### Download
  curl https://storage.googleapis.com/git-repo-downloads/repo > repo
  chmod a+x repo
  mkdir -p android-o/
  cd android-o
  ../repo init -u https://github.com/AsteroidOS/android_manifest -b android-8.0.0_r36
  ../repo sync

  ### Build (can only be done in bash)
  . build/envsetup.sh
  mmma system/core/init/
  mma libminisf

  ### Installation
  cp out/target/product/generic/root/init ../system/bin/
  chmod +x ../system/bin/*
  mkdir -p ../usr/libexec/hal-droid/system/
  cp -r out/target/product/generic/system/lib ../usr/libexec/hal-droid/system

libhybris headers
=================

The second part of this tarball contains header files to compile against
libhybris. There is a script in the libhybris distribution that can pull
the header files from the downloaded android distribution (above).

  git clone https://github.com/libhybris/libhybris
  ./libhybris/utils/extract_headers.sh android-skipjack include 8 0 0

With the system and include directories, you can create the system-dir tarball:

  tar zcvf system.tar.gz system include usr