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cannot find -libsubstrate-dvm -libsubstrate

I got a problem in android.mk.It always show me that cannot find -lsubstrate-dvm and -lsubstrate. I don't know what it is? Could someone tell me how to solve this problem ? Here is the logcat:
Android NDK:non-system libraries in linker flags: -libsubstrate-dvm -libsubstrate
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
cannot find -libsubstrate-dvm
cannot find -libsubstrate
Here is the android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := substrate
LOCAL_SRC_FILES := libsubstrate.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := substrate-dvm
LOCAL_SRC_FILES := libsubstrate-dvm.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := cydiasubstrate.cy
LOCAL_SRC_FILES := cydiasubstrate.cy.cpp
LOCAL_LDLIBS := -llog -L$(LOCAL_PATH) -lsubstrate-dvm -lsubstrate -lz
LOCAL_ARM_MODE := arm
APP_ALLOW_MISSING_DEPS=true
include $(BUILD_SHARED_LIBRARY)
please help me to fix this issue.

substrate-dvm is the name of the module being built, it relies on a prebuild library, not on sources, so you should look for libsubstrate-dvm.so
You could follow the following link for further help:
https://blog.gdssecurity.com/labs/2014/12/16/hooking-non-public-methods-with-the-ndk-using-mobile-substra.html
to include the Substrate libraries. The easiest way to
do this is to navigate to the ‘/sdk/extras/saurikit/cydia_substrate/’
directory and copy ‘substrate.h’ and navigate to the
‘/sdk/extras/saurikit/cydia_substrate/lib//’ directory and copy
‘libsubstrate-dvm.so’ file into the jni folder of the project.

$(LOCAL_PATH) not returning the path to current directory correctly

I am using Android NDK to compile a shared library. I am using the latest build of Android Studio (Android Studio 15- #AI-141.2422023 ). In my cpp code, I am using a thirdparty shared library. When writing the Android.mk file, I have first created a PREBUILT_SHARED_LIBRARY with the following code.
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := essentia
LOCAL_SRC_FILES := $(LOCAL_PATH)/../../../essentia-shared/lib/libessentia.so
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../essentia-shared/include/essentia
include $(PREBUILT_SHARED_LIBRARY)
The problem I am facing is that $(LOCAL_PATH) is behaving a bit weirdly. The path it is returning is
jni/jni/../../../essentia-shared/lib/libessentia.so
I have the following questions:
I am not sure, why there are two jni's appended at the front of the path. Also when I tried to print the value of LOCAL_PATH by using $(warning $(LOCAL_PATH)), it prints jni.
Shouldn't $(LOCAL_PATH) return the absolute path? This is even more confusing because at times I got the absolute path using $(LOCAL_PATH).
PS: I am using the terminal internal to Android Studio to run ndk-build
Edit 1: I run the ndk-build from src/main

$(call my-dir) from src/main for src/main/jni/Android.mk results in "jni". On the other hand, LOCAL_SRC_FILES are always treated relative to the LOCAL_PATH, which is "jni". That's how jni/jni appears for your .so.
On the other hand, all …_INCLUDES are treated relative to working directory, which in your case is src/main from where you launched ndk-build. Due to the delicate nature of current directory, it is a good practice to use absolute paths for all include paths.
So, this is the suggested rewrite of this part of your Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := app-lib
LOCAL_SRC_FILES := a.cpp b.cpp
LOCAL_SHARED_LIBRARIES := essentia
include $(BUILD_SHARED_LIBRARY)
LOCAL_PATH += /../../../essentia-shared
include $(CLEAR_VARS)
LOCAL_MODULE := essentia
LOCAL_SRC_FILES := lib/libessentia.so
LOCAL_EXPORT_C_INCLUDES := $(abspath $(LOCAL_PATH)/include/essentia)
include $(PREBUILT_SHARED_LIBRARY)

Include shared dynamic library in jni ndk build

I am trying to compile a ndk module for my android app with a Shared Library provided with these drivers:
http://www.extendo-printer.de/fileadmin/user_upload/extendo/Drivers/X-56-Hengstler-Extendo-LinuxDrivers-S684018-R2-V1_01-FINAL-2009JUL15.zip
I can compile fine with the defaults (using Hello JNI example). But when I add my code the my C file which references a .so library I need to work with I get compile errors stating it can not find the methods defined in the library. When I try to include it in Android.mk in LOCAL_SRC_FILES i get warnings when it builds (unsupported file extension) but it builds, but than my native method call fails (java.lang linkage error). Is there a proper way to include a .so and than reference it's functions in your native C code?
current Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := x56-jni
LOCAL_LDLIBS := libExoApi.so
LOCAL_SRC_FILES := x56-jni.c
include $(BUILD_SHARED_LIBRARY)
I tried with LOCAL_SHARED_LIBRARIES as well with same build error. I've also tried adding to LOCAL_SRC_FILES as stated above (LOCAL_SRC_FILES := x56-jni.c libExoApi.so) with a "," and as well as \ syntax.
Update
I've updated Android.mk to:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := libExoApi
LOCAL_SRC_FILES := libExoApi.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := x56-jni
LOCAL_LDLIBS := libExoApi.so
LOCAL_SRC_FILES := x56-jni.c
LOCAL_SHARED_LIBRARIES := libExoApi
include $(BUILD_SHARED_LIBRARY)
This fails at:
[exec] Unable to recognise the format of the input file `/var/folders/_6/6jjydzjs457fnpsc9_5cgl980000gn/T//michael/usbserial-generated/libs/armeabi/libExoApi.so'

Linking dependent .so files with ndk-build for Android

I have created a .so file that exposes a native C call to Java via JNI. This works well and I can deploy the app onto my Android system if I just use system libraries in my C code. However, if I want to make calls to functions in other .so files, I cannot get my project to link correctly.
For example, say I have the "libotherso.so" file which contains APIs defined in C that I can call from the "MyJNILibrary.c" code I'm using to generate "libMyJNILibrary.so".
I tried to change my Android.mk file as follows:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := MyJNILibrary
LOCAL_SRC_FILES := MyJNILibrary.c
LOCAL_LDLIBS += -lotherso
include $(BUILD_SHARED_LIBRARY)
But when I call ndk-build on this, I get errors finding -lotherso. Where do I put the "libotherso.so" file so that ndk-build can pick it up?
Thanks for any help you can provide.

LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := otherso
LOCAL_SRC_FILES := ../lib/libotherso.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := MyJNILibrary
LOCAL_SRC_FILES := MyJNILibrary.c
LOCAL_SHARED_LIBRARIES := otherso
include $(BUILD_SHARED_LIBRARY)
Note that LOCAL_SRC_FILES is relative to your LOCAL_PATH.
Don't forget to load your dependency before your own JNI library:
static {
System.loadLibrary("otherso");
System.loadLibrary("MyJNILibrary");
}

how to setup a prebuilt library in jni for android?

hi, i need to use a prebuilt library in my native code so i am placing the library following the example in ndk/samples/native-activity. Below is the structure. Please some one help me out with this error, dsplink.h can not be found. Thanks in advance :)

I thin Vladimir was on the right track.
But don't keep the static lib in the obj folder since that one is delete every run, instead create a jni/modules/precompiled or something and put the stuff there...
what you have is a precompiled static lib. that's what the .a file is.
it's meant to add it to a compilation process so that it'll be in the final binary.
so what you should have is :
#
# DSPLINK
#
include $(CLEAR_VARS)
LOCAL_MODULE := dsplink
LOCAL_SRC_FILES := [path-to-prebuilt-lib]/libdsplink.a
LOCAL_EXPORT_C_INCLUDES := [path-to-dsplink-headers-folder]
include $(PREBUILT_STATIC_LIBRARY)
and also dont forget to include it for the linker in the project .. so below this section in the main shared lib add this line :
LOCAL_STATIC_LIBRARIES := dsplink

Your C file includes dsplink.h file. If you have it, you should add the full path to this file in LOCAL_C_INCLUDES, e.g.
LOCAL_MODULE := jnihello
LOCAL_C_INCLUDES := $(LOCAL_PATH)/inlcudes
By the way, if dsplink.a file is prebuilt, you will be on the safe side to keep it outside of the libs/ folder, so that make clean does not delete it. You can use something like
LOCAL_LDFLAGS += $(LOCAL_PATH)/prebuilt/dsplink.a
to help the linker find the file.

libmath-prebuilt.so is a prebuilt library which has some functions which are used by buyya_read.c. First generate libmath-prebuilt.so using ndk-build and keep in jni folder where buyya_read.c is kept in ur project in elcipse.
Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := math-prebuilt
LOCAL_SRC_FILES = libmath-prebuilt.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := buyya_read
LOCAL_SRC_FILES := buyya_read.c
LOCAL_LDLIBS := -llog
LOCAL_SHARED_LIBRARIES := math-prebuilt
include $(BUILD_SHARED_LIBRARY)
You see the project directory structure in below image.

You should define prebuilt library dsplink in your Android.mk before jnihello project:
#
# DSPLINK
#
include $(CLEAR_VARS)
LOCAL_MODULE := dsplink
LOCAL_SRC_FILES := [path]/libs/armeabi/libdsplink.so
LOCAL_EXPORT_C_INCLUDES := [directory-with-dsplink.h-file]
include $(PREBUILT_STATIC_LIBRARY)
...
# jnihello