(OK) how to compile the source code for Android-x86 (Android 7.1.1)

http://www.android-x86.org/getsourcecode

Introduction

This page has (hopefully) the latest information about how to build Android for x86 platforms like Eee PC. The built images runs well on a real hardware as well as virtual machines (qemu or virtual box).

Now it is very easy to compile Android for x86 platform from our git repositories. You need not to apply any patch. Just follow the below instructions.

The branches in Android-x86 tree

Since AOSP evolves very quickly, we have created different branches corresponding to different releases of AOSP:

• nougat-x86
  Based on Android 7.0 release (Nougat).
• marshmallow-x86
  Based on Android 6.0 release (Marshmallow).
• lollipop-x86
  Based on Android 5.0 release (Lollipop).
• kitkat-x86
  Based on Android 4.4 release (KitKat).
• jb-x86
  Based on Android 4.3 release (Jelly Bean).
• ics-x86
  Based on Android 4.0 release (Ice Cream Sandwich).
• honeycomb-x86
  Based on Android 3.2 release (Honeycomb).
• gingerbread-x86
  Based on Android 2.3 release (Gingerbread).
• froyo-x86
  Based on Android 2.2 release (Froyo).
• eclair-x86
  Based on Android 2.1 release (Eclair).
• donut-x86
  Based on Android 1.6 release (Donut).
• cupcake-x86 (aka android-x86-v0.9)
  Based on Android 1.5 release (Cupcake).

Getting Android-x86 source code

Firstly, follow the AOSP page "Establishing a Build Environment" to configure your build environment. Then

$ mkdir android-x86
$ cd android-x86
$ repo init -u git://git.osdn.net/gitroot/android-x86/manifest -b $branch
$ repo sync --no-tags --no-clone-bundle

Where $branch is any branch name described in the previous section. This will point the projects created or modified by android-x86 to our git server. All the other projects still point to AOSP.

If you have issues to sync from the git protocol, try the alternative http one

$ repo init -u http://scm.osdn.net/gitroot/android-x86/manifest -b $branch
$ repo sync --no-tags --no-clone-bundle

If you hope to keep syncing your tree with Android-x86 repository, just do repo sync. No need to do repo init again. However, sometimes you may see conflicts during repo sync. See the below section for how to solve this situation. 

Note: The Android-x86 repository is very big (about > 10GB). If you encounter problems of sync it, it's likely a network problem or our server is too busy. Repeatedly run 'repo sync' until it succeeds without any error. Do not bother us with any of the syncing problem.

Building the image

Once the repo sync is complete, you can build a cdrom iso image. You need Oracle java 1.6 (OpenJDK may not work) to build branches before (includes) kitkat-x86. . Since lollipop-x86, java 1.7 is required and OpenJDK is supported.

Note: Before froyo-x86 (included), you can build on either a 32-bit or 64-bit host. Since gingerbread-x86, a 64-bit build environment is recommended.

Choose a target

You need to choose a target for the x86 device you want to use/test. We provides several targets for different branches:

• nougat-x86 / marshmallow-x86 / lollipop-x86
  
  • android_x86: for 32-bit x86 platform
  • android_x86_64: for 64-bit x86_64 platform
• kitkat-x86 / jb-x86
  
  • android_x86: for x86 platform
• ics-x86 / honeycomb-x86
  
  • generic_x86: for generic x86 PC/notebook
  • amd_brazos: for AMD Brazos platform
  • eeepc: for ASUS EeePC family only
  • asus_laptop: for some ASUS laptops
  • tegav2: for Tegatech Tegav2 (may work with other Atom N45x based tablets)
• gingerbread-x86 / froyo-x86
  
  • generic_x86: for generic x86 PC/notebook
  • eeepc: for ASUS EeePC family only
  • asus_laptop: for some ASUS laptops
  • tegav2: for Tegatech Tegav2 (may work with other Atom N45x based tablets)
  • sparta: for Dell Inspiron Mini Duo platform
  • vm: for virtual machine (virtual box, qemu, vmware)
  • motion_m1400: for Motion M1400 (Intel Centrino M based with Intel PRO/Wireless)
    
• eclair-x86
  
  • generic_x86: for generic x86 PC/notebook
  • eeepc: for ASUS EeePC family only
  • q1u: for Samsung Q1U
  • s5: for Viliv S5
• donut-x86
  
  • eeepc: for ASUS EeePC family
  • q1u: for Samsung Q1U
  • s5: for Viliv S5

Actually, for historical reason, you have to use eeepc for a generic x86 PC, notebook or netbook before (includes) donut-x86 branch. Since eclair-x86 branch, eeepc is changed to serve ASUS EeePC family only. Do not use it if you are not using an EeePC.

In short, if you don't know how to choose, use eeepc for donut-x86 branch, and use generic_x86 for eclair-x86 to ics-x86 branches. But note generic_x86 is just a base for other targets. It doesn't have some advanced features like hardware acceleration.

Since jb-x86 we tried to use android_x86 as a universal target for all x86 devices. However, it may not optimized for a particular target device. If you are a developer, you can create a target based on android_x86 for your device.

If you want to add new target for your x86 device, refer to the article.

Using lunch command (recommended)

You can source the file build/envsetup.sh into your bash environment to get some shell functions to help the building:

$ . build/envsetup.sh


Now you can select a target by lunch command:

$ lunch $TARGET_PRODUCT-$TARGET_BUILD_VARIANT


where $TARGET_PRODUCT is any target described in the previous section, and possible values of $TARGET_BUILD_VARIANT are eng, user, userdebug. For example,

$ lunch android_x86-userdebug


Then you can build by m command:

$ m -jX iso_img


m command is equivalent to make, but you can use it in any subdirectory of the android-x86 tree.

Since froyo-x86, we also add menu selection to lunch command. Just type lunch, and you will get a list of available targets. Choose a target by inputting its number. Alternatively, just type lunch $number.

Building directly

To build a live cdrom iso image for target android_x86, type:

$ make iso_img TARGET_PRODUCT=android_x86

To generate a live cdrom iso for tegav2, type

$ make iso_img TARGET_PRODUCT=tegav2

Then you will get an iso file out/target/product/x86/android_x86.iso, etc.

If the computer you build on has more then one processor or core, you can take advantage of multiprocessing (or make jobs) by adding -jX to the beginning of your make command:

$ make -jX iso_img TARGET_PRODUCT=android_x86

Replace X by the number of processors you have. For example, if you have a quad core CPU, replace X with 4:

$ make -j4 iso_img TARGET_PRODUCT=android_x86

Using buildspec.mk

You can create a buildspec.mk in your android-x86 directory to remember a particular target product you build often:

TARGET_PRODUCT:=android_x86
TARGET_BUILD_VARIANT:=userdebug
TARGET_BUILD_TYPE:=release
TARGET_KERNEL_CONFIG:=android-x86_defconfig


With your buildspec.mk file in your android-x86 directory, you can just make by

$ make -jX iso_img


Build smaller image

Since marshmallow-x86, the generated Android-x86 core filesystem will be compressed by squashfs by default. Before that, squashfs is used only if you have squashfs-tools 4.0 (older version will not work) installed in your host. The generated iso file is much smaller (only about 30-40%). However, if you hope to disable it for some reasons, add USE_SQUASHFS=0 to make. You can put it to buildspec.mk:

USE_SQUASHFS := 0

Before froyo-x86 (included), If you hope to get a more smaller image, you may remove the debugging symbols by adding

TARGET_STRIP := 1

Since gingerbread-x86, the debugging symbols are stripped by default. Do not use this option anymore.

Testing

The generated image is located at

out/target/product/$TARGET_PRODUCT/$TARGET_PRODUCT.iso

You can easily test the iso file by a virtual box or qemu. On the booting screen, select the VESA or debug mode to boot.

Of course you can burn the iso to a CD disk and test it on a real hardware. On booting it will automatically detect your hardware and load necessary modules. If you have problem with the default frame buffer driver, you may try the VESA mode (select second item on boot screen).

Since honeycomb-x86, we supports the hybrid iso format. That is, the iso could be dumped to a usb disk directly. You may create a bootable USB disk by

$ dd if=out/target/product/x86/android_x86.iso of=/dev/sdX

where /dev/sdX is the device name of your USB disk. This feature is only available for iso files released after 2011/12/25. Note usb_img is deprecated. Do not use it anymore.

Some broken BIOS (e.g., Acer AO) is unable to boot a USB disk created in this way. If so, you may try to create bootable USB drive from the iso file by unetbootin. For both linux and windows user, here are the steps (suggested by Gregory Gee) :

1. Download the ISO image of android-x86.
2. Download UNetbootin from http://unetbootin.sourceforge.net/
3. Make sure you USB key is formatted.  UNetbootin silently fails to work if not formated.  I formatted my USB key fat32.
4. Run UNetbootin
        Select your USB key as the Drive.
        Select the android-x86 ISO file as the disk image.
        Click ok and wait.

It should take a minute to do.  If it only took UNetbootin a few seconds to copy to USB, like my first attempt, then it didn't work.  So remember on future upgrades to reformat your USB key before each android install.

So now you should be able to boot from the USB key.  Well, at least it worked for me.  The UNetbootin is an interesting tool too.

Another choice is the Linux Live USB Creator ( LiLi ) project, which officially support Android-x86.

Advanced

This section describes some useful information for advanced users. You may need good linux expertise to complete it.

Install to USB disk

For advanced linux users, you may create a bootable USB disk by hand. Here are the steps:

1. Install grub to your USB disk
   • find a linux machine with the latest grub installed
   • partition your USB drive with fdisk or gpartd and mark the partition as bootable
   • format that partition to ext3 (recommended) or vfat.
   • mount your usb drive to /mnt
   • cd /mnt
   • grub-install --root-directory=. --no-floppy /dev/<your usb device node name>
   • cd /boot/grub
   • create your menu.lst based on the next section
2. Add this section to menu.lst

   title Run Android-x86
   	kernel /android/kernel root=/dev/ram0 androidboot.hardware=android_x86 SRC=/android
   	initrd /android/initrd.img
   
   title Run Android-x86 (VESA mode)
   	kernel /android/kernel root=/dev/ram0 androidboot.hardware=android_x86 vga=788 SRC=/android
   	initrd /android/initrd.img
   
   title Run Android-x86 (Debug mode)
   	kernel /android/kernel root=/dev/ram0 androidboot.hardware=android_x86 vga=788 SRC=/android DEBUG=1
   	initrd /android/initrd.img

   Note androidboot.hardware= must be set to the target name of the built image.
   

   Since kitkat-x86 the SRC= parameter may be omitted if the system image is in the same directory as the kernel.

3. Create /android directory in the USB disk, and copy the four files kernel initrd.img ramdisk.img system.sfs (or system.img if you set USE_SQUASHFS=0) to it.

Then you can boot from the USB disk and enjoy Android. Note all data are saved to the ramdisk, so all will lose after power off. If you hope to save data to disk, see the next section.

Install to hard disk

Install to a hard disk is just the same as install to a USB disk. Even you do not need to create a new partition. Just copy android files into an existing partition, install grub to the hard disk (if not done yet), and modify the menu.lst.

People still ask, what if my hard disk is empty? How to install grub and copy files into it? There are several ways to do it. I provide two here:

• Boot from any rescue cd like systemrescuecd, and follow the instructions in the previous section.
• Install your favorite linux distribution, then copy android files and modify the grub menu.

Save data to USB/hard disk

We support two ways to save data to your disk.

• Create a subdirectory named data in your /android directory. The user data will be directly saved to that directory. This method only works for ext3 partition.

• Create a separate partition and save data to it. You have to add DATA=<device_name> to the boot option. For example, suppose your data partition is /dev/sda2, then add DATA=sda2 to the boot option.

How to solve conflicts

There are several reason to have conflicts during repo sync, say

• You modify your tree locally.
• The upstream changed. Since we usually keep syncing with original Android repository, sometimes we have to rebase with it. That changes the history and may cause conflicts.

In this section we assume you have conflicts due to the upstream changed. That is, you don't have local modifications. If you do, you have to solve conflicts yourself. If you follow the procedures in this section, you may lose your local modifications.

Here is an example of a conflict in the manifest:

$ repo sync
remote: Counting objects: 71, done.
remote: Compressing objects: 100% (41/41), done.
remote: Total 65 (delta 25), reused 28 (delta 9)
Unpacking objects: 100% (65/65), done.
From git://git.tarot.com.tw/android-x86/platform/manifest
   d53e6c1..2de7a11  android-1.5r2 -> origin/android-1.5r2
 * [new branch]      android-1.5r3 -> origin/android-1.5r3
 * [new branch]      android-sdk-1.5_r3 -> origin/android-sdk-1.5_r3
   d53e6c1..c544020  cupcake    -> origin/cupcake
 * [new branch]      cupcake-release -> origin/cupcake-release
   f4d79b1..6f7e0dd  donut      -> origin/donut
 + 7308d31...4a4f936 lan        -> origin/lan  (forced update)
 + b480a6d...d82496e local      -> origin/local  (forced update)
 + 11c9d96...84345fb master     -> origin/master  (forced update)
 + 5bcbf93...66e92cc mirror     -> origin/mirror  (forced update)
 + 9f3092f...665f9e8 ssh        -> origin/ssh  (forced update)
 + c6037be...d70927f ssh-mirror -> origin/ssh-mirror  (forced update)
 + 00a823f...3ddaf66 test       -> origin/test  (forced update)
 * [new tag]         android-1.5r3 -> android-1.5r3
 * [new tag]         android-sdk-1.5_r3 -> android-sdk-1.5_r3
Fetching projects: 100% (128/128), done.  
project .repo/manifests/
First, rewinding head to replay your work on top of it...
Applying: merge donut, change or add the projects to x86 port
error: patch failed: default.xml:3
error: default.xml: patch does not apply
Using index info to reconstruct a base tree...
Falling back to patching base and 3-way merge...
Auto-merging default.xml
CONFLICT (content): Merge conflict in default.xml
Failed to merge in the changes.
Patch failed at 0001 merge donut, change or add the projects to x86 port

When you have resolved this problem run "git rebase --continue".
If you would prefer to skip this patch, instead run "git rebase --skip".
To restore the original branch and stop rebasing run "git rebase --abort".

repo sync stopped on conflicts. Since we don't have local modifications, just ignore it by git rebase --skip:

$ cd .repo/manifests
$ git rebase --skip
HEAD is now at 4a4f936 add branch for local lan
Applying: add platform/frameworks/policies/base to x86
error: patch failed: default.xml:18
error: default.xml: patch does not apply
Using index info to reconstruct a base tree...
Falling back to patching base and 3-way merge...
Auto-merging default.xml
No changes -- Patch already applied.
Applying: add branch for local lan
error: patch failed: default.xml:1
error: default.xml: patch does not apply
Using index info to reconstruct a base tree...
Falling back to patching base and 3-way merge...
Auto-merging default.xml
No changes -- Patch already applied.

If it complains about another conflict, do git rebase --skip again, until the rebase procedure completes. Usually it is enough, but if you hope to be absolute clean, you can ignore this branch and checkout a new one:

$ git checkout -t kitkat-x86 m/kitkat-x86

This may not be the best approach to solve conflicts, but should be easy enough for beginners. If you have better suggestions, just tell us.

Customize kernel

If you'd like to customize the kernel for your hardware, read this article for details.