I'm trying to debug .so library, using NDK for Android.
I'm able to build .so library, using ndk-build. But when I want to debug my library,
I set ndk-build NDK_DEBUG = 1 and receive following error: make: * empty variable name. Stop.
And also I receive the error: Unable to launch cygpath. Is Cygwin on the path?
Appreciate any help, thanks
You must remove the spaces in the assignment, ie
ndk-build NDK_DEBUG=1
rather than
ndk-build NDK_DEBUG = 1
Related
I am new to this build system, but I've spent dozens of hours trying to get qmake + clang to produce a working android binary. I would appreciate any help or advice. Here is as simple an example as I can come up with:
First, here is a working build command. It gives me a shared object that I can call from android (with Unity, using C# native interops):
C:\Users\deltav\AppData\Local\Android\Sdk2\ndk\21.3.6528147\toolchains\llvm\prebuilt\windows-x86_64\bin\clang.exe ^
-target aarch64-none-linux-android21 -shared -v ^
-DANDROID_ABI=arm64-v8a -DANDROID_ARM_MODE=arm -DANDROID ^
M:\simpleExample\simpleExample.c ^
-o M:\simpleExample\libsimpleExample.so
Here is the verbose output of running that command: https://pastebin.com/18HcnDYh
On the other hand, here is the simpleExample.pro file that is NOT giving me a good binary: https://pastebin.com/wxrx6Myc
Here is the qmake output for building in release mode: https://pastebin.com/KWavwrb7
As you will know, qmake uses a kit to execute the project. My kit: https://imgur.com/a/Ehtmgin
The specific issue that has pushed me down this debugging path is from C# trying to load my shared object like this:
[DllImport("simpleExample")]
public static extern float getSpeedY();
The error that I get is this:
"DllNotFoundException: Unable to load DLL 'simpleExample': The
specified module could not be found."
Again, this error is not an issue if I just build from the CLI without qmake. I do not beleive this is a unity or C# error, as I worked the problem from that side first.
What I have tried so far:
I have used multiple ELF & DWARF tools to compare the ABIs of the generated binaries, which all told me the binaries were identical.
I tweaked and shaved down the clang calls that qmake generated until I got a vaild build command. Unfortunately I can't just replace qmake with the complile command because there are other projects that I need to apply this fix to.
QMake version 3.1
Ironically, CMake basically works out of the box.
Answer: Looking at the clang linking call, you can see QMake 3.1 was adding "libc++shared" as a dependency. I'm not sure why, as this was a C project.
The equivalent CMake project did not do this.
Packaging libc++shared with my binary fixed the issue.
We are attempting to add first class build support for Android to a C++ library. We want to supply a stock Android.mk, and disgorge it from dependencies like a jni subfolder in an Eclipse or Android Studio project directory. That is, we want to:
cd library-src
ndk-build <options>
In the above, library-src is not NDK_PROJECT_PATH. Rather, its the root folder for the library.
We visited the NDK's help (ndk-build -?), but it did not tell us how to remove the assumptions. We tried the following, but it produced an errors:
$ ndk-build -f Android.mk
Android NDK: Could not find application project directory !
Android NDK: Please define the NDK_PROJECT_PATH variable to point to it.
/opt/android-ndk-r10e/build/core/build-local.mk:143: *** Android NDK: Aborting
Stop.
Attempting to set NDK_PROJECT_PATH results in a similar error:
$ NDK_PROJECT_PATH=. ndk-build -f Android.mk
Android NDK: Your APP_BUILD_SCRIPT points to an unknown file: ./jni/Android.mk
/opt/android-ndk-r10e/.../add-application.mk:199: *** Android NDK: Aborting...
Stop.
And attempting to set APP_BUILD_SCRIPT results in a similar error:
$ NDK_PROJECT_PATH=. APP_BUILD_SCRIPT=Android.mk ndk-build -f Android.mk
Android NDK: Your APP_BUILD_SCRIPT points to an unknown file: ./jni/Android.mk
/opt/android-ndk-r10e/.../add-application.mk:199: *** Android NDK: Aborting...
Stop.
How do we use ndk-build without the jni directory?
Its important that we remove the limitations/assumptions. If we can't remove them, then we can't automate building and testing. If we can't automate building and testing, then we can't add the support because our governance has some QA and testing gates that we won't be able to pass through. (I'm willing to tolerate a manual adb push to test on-device).
I must admit that I don't understand your limitations. Why adding file library-src/Android.mk is OK, but library-src/jni/Android.mk breaks your QA and testing gates. Furthermore, Android.mk is usually not enough to launch a build. Whether you want to choose the STL variation, or ABI, or toolchain, it is natural to define these settings in a different file, Application.mk, which also goes to the jni directory by convention. Add library-src/jni directory, and Android developers will thank you when their tools of trade get upgrades and they can stay with the standard configuration.
But Android build is a very flexible system, and you can achieve literally what you ask for.
The experiments that you made did not work because ndk-build is simply a thin wrapper around GNU make, and treats environment variables with low priority.
ndk-build APP_BUILD_SCRIPT=Android.mk NDK_PROJECT_PATH=.
will most likely simply work for you. If you need more control, you can use something like
ndk-build APP_BUILD_SCRIPT=Android.mk NDK_PROJECT_PATH=. APP_STL=gnustl_static APP_ABI=armeabi-v7a APP_PLATFORM=android-19 NDK_TOOLCHAIN_VERSION=4.9
You can control the output directories, too. See NDK_APP_OUT, NDK_APP_LIBS_OUT.
One last hint: if your global build process is based on make, you can invoke $(MAKE) directly instead of going through ndk-build. It is also OK if you require standalone toolchain to keep platform-independent make logic.
I am currently trying to debug native code in Android via ndk-gdb but I am having some troubles.
Even if I start a very simple project (let's say for example a default cocos2d-x v3 project) and run
ndk-build NDK_DEBUG=1
I end up with the following folder structure inside my android project
...
libs/
armeabi/
libcocos2dcpp.so
...
instead of the expected:
...
libs/
armeabi/
gdb.setup
gdbserver
libcocos2dcpp.so
...
In order to use ndk-gdb I need those two gdb files.
I am using cocos version 3.2 and Android NDK version r9d.
Isn't NDK_DEBUG=1enough for the gdb files to be generated? I have also tried withandroid:debuggable="true" inside my manifest file but it didn't work.
Edit
After running the command suggested by Digit I found a very suspicious line
Android NDK: Application 'local' forced *not* debuggable through NDK_DEBUG
when running the command ndk-build NDK_LOG=1 NDK_DEBUG=1
BUT
if I change to ndk-build NDK_LOG=1 NDK_DEBUG=true I get
Android NDK: Application 'local' forced debuggable through NDK_DEBUG
So it is ok now, really weird though how =1 is not considered true.
Can you paste the output of 'ndk-build NDK_LOG=1 NDK_DEBUG=1', this should contain more information about what ndk-build is doing, and is likely to provide an explanation.
I want to use andengine in my android studio project but I have ndk error while building.
Error:Execution failed for task ':andEngine:compileReleaseNdk'.
> com.android.ide.common.internal.LoggedErrorException: Failed to run command:
D:\Android\android-ndk-r9d\ndk-build.cmd NDK_PROJECT_PATH=null APP_BUILD_SCRIPT=D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\Android.mk APP_PLATFORM=android-19 NDK_OUT=D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\obj NDK_LIBS_OUT=D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\lib APP_ABI=all
Error Code:
2
Output:
D:/Android/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld.exe: D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\obj/local/armeabi-v7a/objs/andengine_shared/D_\Android\workspace\simpleclock\simple_clock_as\andEngine\src\main\jni\src\GLES20Fix.o: in function Java_org_andengine_opengl_GLES20Fix_glVertexAttribPointer:GLES20Fix.c(.text.Java_org_andengine_opengl_GLES20Fix_glVertexAttribPointer+0x40): error: undefined reference to 'glVertexAttribPointer'
D:/Android/android-ndk-r9d/toolchains/arm-linux-androideabi-4.6/prebuilt/windows-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld.exe: D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\obj/local/armeabi-v7a/objs/andengine_shared/D_\Android\workspace\simpleclock\simple_clock_as\andEngine\src\main\jni\src\GLES20Fix.o: in function Java_org_andengine_opengl_GLES20Fix_glDrawElements:GLES20Fix.c(.text.Java_org_andengine_opengl_GLES20Fix_glDrawElements+0x30): error: undefined reference to 'glDrawElements'
collect2: ld returned 1 exit status
make.exe: *** [D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\obj/local/armeabi-v7a/libandengine_shared.so] Error 1
I suppose I'm missing some OpenGL files?
The Android Gradle plugin's NDK task does not actually use any Android.mk file that you may have provided in your jni/ folder. This was a great source of confusion for me until I figured that out.
It generates a intermediate Android.mk file during the build, based on parameters that you have set in your Gradle build script and on the content of your jni/ folder.
You can see this for yourself by inspecting the source for its NdkCompile task at https://android.googlesource.com/platform/tools/base/+/55aebda607efcc29b8d9d5e1a99d446e320ff288/build-system/gradle/src/main/groovy/com/android/build/gradle/tasks/NdkCompile.groovy.
Note the writeMakeFile(...) method on line 126.
This is why the error you are getting from the ndk-build command that runs as part of your Gradle build references the build script APP_BUILD_SCRIPT=D:\Android\workspace\simpleclock\simple_clock_as\andEngine\build\intermediates\ndk\release\Android.mk, not something like APP_BUILD_SCRIPT=D:\Android\workspace\simpleclock\simple_clock_as\andEngine\src\main\jni\Android.mk as you might expect and want it to.
There is no way of getting the Android Gradle plugin's NDK task to use your own Android.mk file (believe me if there was I would have found it!).
You have two options for getting your NDK code compiling as part of Gradle:
Figure out the correct configuration to put in your build.gradle so that the generated Android.mk file contains the required LOCAL_LDLIBS := -lGLESv2 line and any of the other lines from https://github.com/nicolasgramlich/AndEngine/blob/GLES2/jni/Android.mk that are required.
Write a custom NDK compile task that uses the AndEnginge's Android.mk file directly. I've recently had to do this myself for an NDK source set that requires more parameters than the Android Gradle plugin currently supports passing via Gradle, so it if comes to this I can provide help.
I think in this case option 1 is open and so of course the preferable solution.
Something like this added to the android defaultConfig block should work:
android {
defaultConfig {
ndk {
moduleName "myNDKModule"
stl "stlport_shared"
ldLibs "lGLESv2"
cFlags "-Werror"
}
}
}
Unfortunately I am very much not a C/native code expert (I know practically nothing) so cannot guess whether AndEngine needs LOCAL_MODULE_FILENAME and LOCAL_EXPORT_C_INCLUDES to be set to build correctly. If it does, you'll need to go with approach 2 (at least until if/when the Android Gradle NDK task supports configuring them). Though I have just checked out the AndEngine git repo and successfully run ndk-build after having removed them from its Android.mk file, which is promising.
(I found which NDK properties can be parametrised via inspection of https://android.googlesource.com/platform/tools/base/+/55aebda607efcc29b8d9d5e1a99d446e320ff288/build-system/gradle/src/main/groovy/com/android/build/gradle/internal/dsl/NdkConfigDsl.java).
I had a similar issue, and this video https://www.youtube.com/watch?v=0-rYK2oh8oo helped me to fix the build issues. Basically, you need to download (and extract) NDK from here: http://developer.android.com/ndk/downloads/index.html and specify the NDK location in Module Settings. Also, you need to alter the andEngine's build.gradle file to include
sourceSets{
main{
jni.srcDirs = []
}
}
Android.mk actually includes the line?
https://github.com/nicolasgramlich/AndEngine/blob/GLES2/jni/Android.mk#L10
LOCAL_LDLIBS := -lGLESv2
These errors indicate it.
error: undefined reference to 'glVertexAttribPointer'
error: undefined reference to 'glDrawElements'
I want to know how to build libav on windows7 using cygwin. I've tried the following steps :
1-change the directory using cd command to libav_file_directory/android(android folder is empty where the .so file will be saved as far as my knowledge is concern).
2-execute the ./ndk-buil command.
I got the following as result:
*Android NDK: Could not find application project directory !
Android NDK: Please define the NDK_PROJECT_PATH variable to point to it.
/cygdrive/c/Users/balwant.singh.TA/Desktop/Android/android-ndk-r8/build/core/build-local.mk:130: * Android NDK: Aborting . Stop.*
plese reply with solution, and also I want to know which all android media player uses the libav as their native code.
1.)Set all your paths(Java_Home
2.)Set NDK_HOME to Ndk-Build Path
3.)Run Cygwin
4.)GO to project Library path
5.)Run make command
6.)then Run ndk-build