How do I compile simple native code using Android.mk?

Question

In particular I am trying to compile chainDD's su binary. I tried to use ndk-build but it seems I need to set NDK_PROJECT_PATH but what this should be set to is not described in the documentation.

Answer 1

First, make sure you have the NDK:

http://developer.android.com/tools/sdk/ndk/index.html

Here is the easiest way to compile a C binary for your phone:

http://developer.android.com/tools/sdk/ndk/index.html

http://www.kandroid.org/ndk/docs/STANDALONE-TOOLCHAIN.html

Usually $NDK(may be different) =

Linux:

/home/<user>/android-ndk

Mac OS X:

/Users/<user>/android-ndk

Both: $HOME/android-ndk

In Terminal:

# create tool-chain - one line $NDK/build/tools/make-standalone-toolchain.sh --platform=android-3 --install-dir=/tmp/my-android-toolchain  # add to terminal PATH variable export PATH=/tmp/my-android-toolchain/bin:$PATH  # make alias CC be the new gcc binary export CC=arm-linux-androideabi-gcc  # compile your C code(I tried hello world) $CC -o foo.o -c foo.c  # push binary to phone adb push foo.o /data/local/tmp  # execute binary adb /data/local/tmp/foo.o 

Please let me know if I can help!

Regards,

Answer 2

You need establish your project folder like this:

project_root

|__ jni/ (include Android.mk and your C/C++ code)

|__ other_directory

The jni directory can't change name. and run ndk-build in project_root directory.