how to use adb and gdbserver with VirtualBox

http://www.android-x86.org/documents/debug-howto

1. use adb:

• In the VirtualBox network configuration, it is simplest to configure it for Host-Only or Bridged.
• boot up Android iso image on the VirtualBox.
• setup ethernet (normally, it will do DHCP by default)
• find the IP address of the android VM, by going to the console <Alt-F1> and then typing:netcfg
• you can go back to the UI by pressing <Alt-F7>
• on you host machine, cd <android source code root directory>/out/host/linux-x86/bin/
• ./adb kill-server
• ./adb connect <VirtualBox IP address>:5555, after this command, you should see something like below

            * daemon not running. starting it now *
            * daemon started successfully *
            connected to <VirtualBox IP address>:5555

• ./adb logcat to dump the debug log

2. using adb with a NAT'ed VM

• The steps above work nicely if you have a VM which is set up to use Bridged or Host-Only adapters
• However, if you have a NAT'ed VM you cannot connect to the VM IP from the host
• You will need to set up port forwarding for a host port to be forwarded to the VM port 5555 (which is adb)
  VBoxManage modifyvm <VMName> --natpf1 adb,tcp,*,<localport>,*,5555
  Example from one machine:
  VBoxManage modifyvm froyo --natpf1 adb,tcp,*,5555,*,5555
• Once this is done, you should see the local port (i.e. 5555 in this case) bound on the host via netstat -a
• You can now connect to the VM by adb localhost:5555  
  

2a. using adb with KVM (qemu)

If you are using KVM instead of Virtualbox you may find the following useful.

Example of running a iso using kvm:
kvm -soundhw es1370 -net nic -net user,hostfwd=tcp::4444-:5555 -cdrom buildname.iso

note the networking arguments: this allows "user networking" which doesn't need root access, while still allowing adb connections, by forwarding them on port 4444 of localhost, so to connect you would use:
adb connect localhost:4444

to disconnect simply (you'll need to do this after stopping/restarting a VM session):
adb disconnect

Its also possible to pass-through usb devices from the host to android guest running in kvm by adding the parameters:
-usb -usbdevice host:2.*
where in the above example that would pass through all devices on the number 2 usb host bus.

3. how to use gdb with gdbserver:

Android-x86 comes with a preinstalled gdbserver. And you can find it in /sbin/gdbserver. To use gdb to debug your process, you need to:

• set up host-only network as mentioned earlier
• in the terminal emulator, run su
• in the terminal emulator, run gdbserver <VirtualBox ip address>:1234 [application binary name with the path] or [--attach pid]
• on your host machine, run gdb [path of your application binary]
• gdb > target remote <VirtualBox ip address>:1234
• gdb > set solib-search-path <the path to all the shared library binaries>
• gdb > c

4. Stop zygote to run automatically:

in the vendor/asus/eeepc/init.rc, change following lines 

service zygote /system/bin/app_process -Xzygote /system/bin --zygote --start-system-server

    socket zygote stream 666

    onrestart write /sys/android_power/request_state wake

    onrestart write /sys/power/state on

to:

service zygote /system/bin/app_process -Xzygote /system/bin --zygote --start-system-server

    socket zygote stream 666

    onrestart write /sys/android_power/request_state wake

    onrestart write /sys/power/state on

    disabled

    oneshot

To start zygote manually just do "start zygote" from the command line.