Android NDK build shared library

Question

I am new in NDK and i want to use ac library in my application. I try with a simple c file and it work. I succeded to send and receive data between the two api. But when i want to introduce an existing c library i have this kind of error when i run ndk-build.

root@xxx:~/workspace/Myproject# ndk-build
Android NDK: WARNING: APP_PLATFORM android-16 is larger than android:minSdkVersion 8 in /root/workspace/MyOpus/AndroidManifest.xml    
[armeabi-v7a] Compile thumb  : my_manager <= myencoder.c
[armeabi-v7a] SharedLibrary  : libmy_manager.so
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: error: ./obj/local/armeabi-v7a/libopus.so: incompatible target
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/my_manager/src/myencoder.o: in function myEncodeOpus:/root/workspace/MyOpus/jni/src/myencoder.c:81: error: undefined reference to 'opus_encoder_create'
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/my_manager/src/myencoder.o: in function myEncodeOpus:/root/workspace/MyOpus/jni/src/myencoder.c:84: error: undefined reference to 'opus_strerror'
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/my_manager/src/myencoder.o: in function myEncodeOpus:/root/workspace/MyOpus/jni/src/myencoder.c:93: error: undefined reference to 'opus_encoder_ctl'
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/my_manager/src/myencoder.o: in function myEncodeOpus:/root/workspace/MyOpus/jni/src/myencoder.c:96: error: undefined reference to 'opus_strerror'
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/my_manager/src/myencoder.o: in function myEncodeOpus:/root/workspace/MyOpus/jni/src/myencoder.c:120: error: undefined reference to 'opus_encode'
/usr/local/mes_installations/android_tool/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: ./obj/local/armeabi-v7a/objs/my_manager/src/myencoder.o: in function myEncodeOpus:/root/workspace/MyOpus/jni/src/myencoder.c:123: error: undefined reference to 'opus_strerror'
collect2: ld returned 1 exit status
make: *** [obj/local/armeabi-v7a/libmy_manager.so] Error 1

How can i solve this problem? I read all the Android.mk documentation but i did not see any thing to solve it. Regards

Answer 1

you said you succeed to create shared library libmy_manager . in Android.mk specify the path of libmy_manager.so and the path of header files

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)
LOCAL_MODULE := libmy_manager
LOCAL_SRC_FILES := libmy_manager.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include  #path of header file with define               
                                                  # function in libmy_manager
include $(PREBUILT_SHARED_LIBRARY)


include $(CLEAR_VARS)
LOCAL_MODULE    := my_manager
LOCAL_SRC_FILES := my_manager.c
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
LOCAL_SHARED_LIBRARIES := libmy_manager
include $(BUILD_SHARED_LIBRARY)