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MSI SDR device sample code does not compile

I am trying to interface with an MSI SDR dongle, using an android app
This device is a clone of the SDRPlay SDR device, and is compatible with it's software and drivers
I am trying to interface with this using an OTG cable and android phone
The android drivers for this can be downloaded from here https://www.sdrplay.com/downloads/
It is in the Android tab under the API/HW – V2.11 (15TH NOV 2017) link (https://www.sdrplay.com/anddl.php)
A possible sample code for this driver can be found here: https://www.sdrplay.com/docs/AndroidIntegrationNote.pdf
Before making the full android program it says the library (libmir_sdr_api.a) should be built into an .so library file using ndk-build
I currently have Android's hello-jni sample project from here: https://github.com/android/ndk-samples/tree/android-mk/hello-jni
I have replaced the jni folder using the Android.mk file, libmir_sdr_api.a, mir_sdr.h, initialization-jni.cpp, demod-jni.cpp and demod-jni.h files mentioned in section 3 of the AndroidIntegrationNote.pdf file I linked above
When I execute ndk-build from the hello-jni project folder, I get he following error:
Android NDK: Found platform level in ./default.properties. Setting APP_PLATFORM to android-25.
Android NDK: android-25 is an alias for android-24. Adjusting APP_PLATFORM to match.
[arm64-v8a] Gdbserver : [aarch64-linux-android] libs/arm64-v8a/gdbserver
[arm64-v8a] Gdbsetup : libs/arm64-v8a/gdb.setup
[x86_64] Gdbserver : [x86_64-linux-android] libs/x86_64/gdbserver
[x86_64] Gdbsetup : libs/x86_64/gdb.setup
[armeabi-v7a] Gdbserver : [arm-linux-androideabi] libs/armeabi-v7a/gdbserver
[armeabi-v7a] Gdbsetup : libs/armeabi-v7a/gdb.setup
[x86] Gdbserver : [i686-linux-android] libs/x86/gdbserver
[x86] Gdbsetup : libs/x86/gdb.setup
make: *** No rule to make target 'jni/initialisation-jni.cpp', needed by 'obj/local/arm64-v8a/objs-debug/mirics-jni/initialisation-jni.o'. Stop.
I am used to compiling NDK code suing Android Studio and cmake so I am not sure what is going on here. I have not been able to link the .a file through cmake either so I thought of giving the driver manufacturer's sample code a try, but it not working either. Is the Android.mk file in pdf file linked earlier incomplete, or am I not building it correctly? These are the contents of the Android.mk file:
# $(call my-dir) returns the local directory which is the jni directory
LOCAL_PATH := $(call my-dir)
# libmir_sdr_api.a – this section creates a version of the Mirics API to be used below
include $(CLEAR_VARS)
LOCAL_MODULE := mir_sdr_api-prebuilt
LOCAL_SRC_FILES := libmir_sdr_api.a
LOCAL_EXPORT_C_INCLUDES := $(call my-dir)
include $(PREBUILT_STATIC_LIBRARY)
include $(CLEAR_VARS)
# mirics-jni – this section uses the jni C++ source code to build the dynamic library
LOCAL_MODULE := mirics-jni
LOCAL_SRC_FILES := initialisation-jni.cpp demod-jni.cpp
LOCAL_C_INCLUDES := $(call my-dir)
LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib
LOCAL_STATIC_LIBRARIES := mir_sdr_api-prebuilt
include $(BUILD_SHARED_LIBRARY)

Regarding missing jni/initialisation-jni.cpp, you probably have the file jni/initialization-jni.cpp instead.
Also, unfortunately, the document is wrong. You can only use $(call my-dir) easily at the top of the file. Luckily, Android NDK adds the jni directory to includes path for you. Still, to be on the safe side, better write:
# $(call my-dir) returns the local directory which is the jni directory
LOCAL_PATH := $(call my-dir)
# libmir_sdr_api.a – this section creates a version of the Mirics API to be used below
include $(CLEAR_VARS)
LOCAL_MODULE := mir_sdr_api-prebuilt
LOCAL_SRC_FILES := libmir_sdr_api.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)
include $(PREBUILT_STATIC_LIBRARY)
include $(CLEAR_VARS)
# mirics-jni – this section uses the jni C++ source code to build the dynamic library
LOCAL_MODULE := mirics-jni
LOCAL_SRC_FILES := initialization-jni.cpp demod-jni.cpp
LOCAL_C_INCLUDES := $(LOCAL_PATH)
LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib
LOCAL_STATIC_LIBRARIES := mir_sdr_api-prebuilt
include $(BUILD_SHARED_LIBRARY)
Finally, pay attention to your build process. You only have one kind of the libmir_sdr_api.a static library, it's built for a 32-bit ARM CPU. Therefore you cannot build your libmirics-jni.so for other architectures. Add
APP_ABIS = armeabi-v7a
to your Application.mk file, or specify
abifilters = armeabi-v7a
in your build.gradle, if you build your library in Android Studio.

How to resolve "Relocations in Generic ELF" during ndk-build?

I'm trying to build a static library using a standalone toolchain for a project that has its own build process, which I then wrap with a C++ library and expose to Android (compiled with ndk-build). However, on the ndk-build step I receive the following error:
➜ jni /Users/chrisfosterelli/Library/Android/sdk/ndk-bundle/ndk-build
[arm64-v8a] Compile++ : wrapper <= wrapper.cpp
In file included from /Users/chrisfosterelli/workspace/android/jni/wrapper.cpp:9:
In file included from ../prebuild/include/valhalla/meili/universal_cost.h:7:
In file included from ../prebuild/include/valhalla/sif/dynamiccost.h:4:
In file included from ../prebuild/include/valhalla/baldr/directededge.h:5:
../prebuild/include/valhalla/baldr/graphconstants.h:432:11: warning: 21 enumeration values not handled in switch: 'kRoad', 'kRamp', 'kTurnChannel'... [-Wswitch]
switch (use) {
^
1 warning generated.
[arm64-v8a] SharedLibrary : libwrapper.so
/Users/chrisfosterelli/Library/Android/sdk/ndk-bundle/toolchains/aarch64-linux-android-4.9/prebuilt/darwin-x86_64/lib/gcc/aarch64-linux-android/4.9.x/../../../../aarch64-linux-android/bin/ld: /Users/chrisfosterelli/workspace/android/jni/../prebuild/libvalhalla_meili.a(libvalhalla_meili_la-map_matcher_factory.o): Relocations in generic ELF (EM: 62)
[...above message repeated many times...]
/Users/chrisfosterelli/workspace/android/jni/../prebuild/libvalhalla_meili.a: error adding symbols: File in wrong format
clang++: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [/Users/chrisfosterelli/workspace/android/obj/local/arm64-v8a/libwrapper.so] Error 1
➜ jni ls /Users/chrisfosterelli/Library/Android/sdk/ndk-bundle/
This error indicates, as far as I can tell, that I'm trying to mix and match binaries compiled for different architectures. However, from what I can tell the library is the correct architecture:
root#eacbdb1c0e46:/meili/meili2/newtest# ar x libvalhalla_meili.a
root#eacbdb1c0e46:/meili/meili2/newtest# file libvalhalla_meili_la-map_matcher_factory.o
libvalhalla_meili_la-map_matcher_factory.o: ELF 64-bit LSB relocatable, ARM aarch64, version 1 (SYSV), not stripped
root#eacbdb1c0e46:/meili/meili2/newtest#
FWIW, these are my current Application.mk,
APP_STL := c++_static
APP_CPPFLAGS := -frtti -std=gnu++11 -D_GLIBCXX_USE_C99
APP_CPPFLAGS += -fexceptions
NDK_TOOLCHAIN_VERSION := clang
APP_LDFLAGS := -latomic
APP_PLATFORM := android-21
APP_ABI := arm64-v8a
and Android.mk,
LOCAL_PATH := $(call my-dir)
# static library info
include $(CLEAR_VARS)
LOCAL_MODULE := libvalhalla_meili
LOCAL_SRC_FILES := ../prebuild/libvalhalla_meili.a
LOCAL_EXPORT_C_INCLUDES := ../prebuild/include
include $(PREBUILT_STATIC_LIBRARY)
# wrapper info
include $(CLEAR_VARS)
LOCAL_C_INCLUDES += ../prebuild/include
LOCAL_MODULE := wrapper
LOCAL_SRC_FILES := wrapper.cpp
LOCAL_STATIC_LIBRARIES := libvalhalla_meili
include $(BUILD_SHARED_LIBRARY)
Any ideas how to resolve this? I've tried a number of things but all of them lead to more (more obscure) errors, so I'm hoping someone here can point me in the correct direction!

I discovered the problem, but I wish I had a more insightful answer. Apparently the build process had created two library files. The one that I inspected was, of course, ARM64. However the one that I actually copied to the Android device was x86.
So, the error message was correct and so was the library file, but there was more than one file involved. If you're running into the same problem and pretty sure your library is ARM64, double check that's actually the same file that is being compiled into the ndk build!

undefined reference to ndk boost android

I have a problem when creating an executable with ndk using the BOOST libraries in c ++ using already mentioned ndk, this is the problem
C:\Users\GENERAL\Downloads\Compressed\tcpproxy\proxy\jni>ndk-build
[armeabi] Compile++ thumb: proxy <= tcpproxy_server.cpp
[armeabi] Executable : proxy
C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//jni/boost_1_56_0/boost/sys
tem/error_code.hpp:322: error: undefined reference to 'boost::system::system_cat
egory()'
C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//jni/boost_1_56_0/boost/thr
ead/exceptions.hpp:51: error: undefined reference to 'boost::system::system_cate
gory()'
C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//jni/boost_1_56_0/boost/asi
o/error.hpp:225: error: undefined reference to 'boost::system::system_category()
'
C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//jni/boost_1_56_0/boost/asi
o/error.hpp:225: error: undefined reference to 'boost::system::system_category()
'
C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//jni/boost_1_56_0/boost/sys
tem/error_code.hpp:221: error: undefined reference to 'boost::system::generic_ca
tegory()'
C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//jni/boost_1_56_0/boost/sys
tem/error_code.hpp:222: error: undefined reference to 'boost::system::generic_ca
tegory()'
collect2.exe: error: ld returned 1 exit status
make.exe: *** [C:/Users/GENERAL/Downloads/Compressed/tcpproxy/proxy//obj/local/a
rmeabi/proxy] Error 1
Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES += $(LOCAL_PATH)/boost_1_56_0 #patch of include BOOST
LOCAL_MODULE := proxy
LOCAL_SRC_FILES := tcpproxy_server.cpp
include $(BUILD_EXECUTABLE)
Application.mk
APP_CFLAGS += -fexceptions
APP_STL := gnustl_static
NDK_TOOLCHAIN_VERSION := 4.8
APP_CPPFLAGS := -std=c++11
that is the error that I get when compiling. already investigate but can not find the solution so please thank your answer to be able to repair it and because generating that error thanks

You may need to add the boost_system library. You can add -lboost_system to your linker flags to find related library symbols in Android.mk (Assuming that boost is built as static):
LOCAL_STATIC_LIBRARIES = -lboost_system ...
include $(BUILD_STATIC_LIBRARY)

Building other library with android ndk project

I am having a hard time in integrating dlib with my android studio NDK project, Basically I want to use the library in my native C++ code, I am not sure about the standard way of doing the same, I have my Android.mk file which is under app/src/main/jni as :
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := dlib
LOCAL_SRC_FILES := dlib/all/source.cpp
LOCAL_CPPFLAGS = -I/opt/X11/include
include $(BUILD_STATIC_LIBRARY)
include $(CLEAR_VARS)
OPENCVROOT:= /Users/anmoluppal/Downloads/OpenCV-android-sdk
OPENCV_CAMERA_MODULES:=on
OPENCV_INSTALL_MODULES:=on
OPENCV_LIB_TYPE:=SHARED
include ${OPENCVROOT}/sdk/native/jni/OpenCV.mk
LOCAL_MODULE := ndkDemo
LOCAL_STATIC_LIBRARIES := dlib
LOCAL_SRC_FILES := main.cpp face_detector.cpp face_tracker.cpp ft_data.cpp patch_model.cpp shape_model.cpp
include $(BUILD_SHARED_LIBRARY)
And the Application.mk file looks something like:
APP_STL := gnustl_static
APP_CPPFLAGS += -fexceptions -frtti
APP_ABI := all
And the project structure is:
+ app
---+ src
-----+ main
-------+ jni
---------+ dlib
---------+ Application.mk
---------+ Android.mk
---------+ (... Other .cpp files)
And I am getting a lot of undefined reference to errors which are referring to X11 library on Mac, which is indeed installed properly, I want to know if this is the correct way of including a library in NDK project? Or alternatively I need to create a Android.mk file in dlib folder as well? Also I am unaware of the main .cpp files which are required as LOCAL_SRC_FILES for the .mk file.
After ndk-build I get the following output:
[arm64-v8a] Compile++ : ndkDemo <= main.cpp
[arm64-v8a] Compile++ : ndkDemo <= face_detector.cpp
[arm64-v8a] Compile++ : ndkDemo <= face_tracker.cpp
[arm64-v8a] Compile++ : ndkDemo <= ft_data.cpp
[arm64-v8a] Compile++ : ndkDemo <= patch_model.cpp
[arm64-v8a] Compile++ : ndkDemo <= shape_model.cpp
[arm64-v8a] Compile++ : dlib <= source.cpp
[arm64-v8a] StaticLibrary : libdlib.a
[arm64-v8a] SharedLibrary : libndkDemo.so

There are several things you need to consider.
First: The libraries you link need to be cross compiled for the respective ABIs. Your Application.mk says all so you need to provide all (arm, x86, MIPS,...). Are your libraries prebuilt? In that case you will need to cross compile them manually.
You are missing the include directories for your libraries. You can include them with :
LOCAL_EXPORT_C_INCLUDES
LOCAL_C_INCLUDES
This is the way to go instead of using CPP-Flags.
There are some other problems in your makefile which you should resolve by inspecting makefiles of other people on stackoverflow or search in the NDK documentation. For example I dont think that you can provide the LOCAL_SRC_FILES like you did, you need to separate them by backslashes like that:
LOCAL_SRC_FILES := \ x.cpp \ y.cpp
Your project structure is fine, I think you are almost there.
Feel free to provide the new version of your makefiles when you resolved the linking errors.

Android NDK cannot find -lGLESv

I am getting the following errors when I try to perform an NDK build, can anyone help me please?
I did the setup instruction exactly like what are written in "Beginning Android C++ Game Development". every step except the 9th:
"Click the NativeActivity node in the Application Nodes window and click Add once more. Enter the Name as android.app.lib_name and the Value as the LOCAL_MODULE name, which can be found in the Android.mk file in the project’s jni folder."
Errors :
10:44:23 ** Incremental Build of configuration Default for project
HelloDroid ** "C:\ndk\ndk-build.cmd" all Android NDK:
WARNING:jni/Android.mk:HelloDroid-Test: non-system libraries in linker
flags: -lGLESv Android NDK: This is likely to result in
incorrect builds. Try using LOCAL_STATIC_LIBRARIES Android NDK:
or LOCAL_SHARED_LIBRARIES instead to list the library dependencies of
the Android NDK: current module [armeabi] SharedLibrary :
libHelloDroid-Test.so
C:/ndk/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld.exe:
error: cannot find -lGLESv collect2: ld returned 1 exit status
make.exe: * [obj/local/armeabi/libHelloDroid-Test.so] Error 1
10:44:23 Build Finished (took 226ms)

I found the problem.
I just needed to edit the Android.mk
it now looks like this:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := hellodroid
LOCAL_SRC_FILES := hellodroid.cpp
LOCAL_LDLIBS := -llog -landroid -lEGL -lGLESv2
LOCAL_STATIC_LIBRARIES := android_native_app_glue
include $(BUILD_SHARED_LIBRARY)
$(call import-module, android/native_app_glue)

As the error states, there is no lib GLESv.
Which version of OpenGL ES are you using, 1 or 2?
The linker flags are -lGLESv1_CM and -lGLESv2, respectively.