Android gradle ndk jni build with external library & native debugging (ARToolkit)

Question

I am trying to have the Android studio to be my main development IDE for java AND c/c++ code. I want to be able to debug native code.

In this case i am trying to use ARToolkit5 as a library.

Due to some examples in the ARToolkit5 i am having this build file.

i am having this Android.mk file

MY_LOCAL_PATH := $(call my-dir)
LOCAL_PATH := $(MY_LOCAL_PATH)

# Pull ARToolKit into the build
include $(CLEAR_VARS)
ARTOOLKIT_DIR := $(MY_LOCAL_PATH)/../../../../../artoolkit5/android
ARTOOLKIT_LIBDIR := $(call host-path, $(ARTOOLKIT_DIR)/obj/local/$(TARGET_ARCH_ABI))
define add_artoolkit_module
    include $(CLEAR_VARS)
    LOCAL_MODULE:=$1
    LOCAL_SRC_FILES:=lib$1.a
    include $(PREBUILT_STATIC_LIBRARY)
endef
ARTOOLKIT_LIBS := ar2 kpm util eden argsub_es armulti ar aricp jpeg arvideo
LOCAL_PATH := $(ARTOOLKIT_LIBDIR)
$(foreach module,$(ARTOOLKIT_LIBS),$(eval $(call add_artoolkit_module,$(module))))

LOCAL_PATH := $(MY_LOCAL_PATH)

# Android arvideo depends on CURL.
CURL_DIR := $(ARTOOLKIT_DIR)/jni/curl
CURL_LIBDIR := $(call host-path, $(CURL_DIR)/libs/$(TARGET_ARCH_ABI))
define add_curl_module
    include $(CLEAR_VARS)
    LOCAL_MODULE:=$1
    #LOCAL_SRC_FILES:=lib$1.so
    #include $(PREBUILT_SHARED_LIBRARY)
    LOCAL_SRC_FILES:=lib$1.a
    include $(PREBUILT_STATIC_LIBRARY)
endef
#CURL_LIBS := curl ssl crypto
CURL_LIBS := curl
LOCAL_PATH := $(CURL_LIBDIR)
$(foreach module,$(CURL_LIBS),$(eval $(call add_curl_module,$(module))))

LOCAL_PATH := $(MY_LOCAL_PATH)
include $(CLEAR_VARS)

# ARToolKit libs use lots of floating point, so don't compile in thumb mode.
LOCAL_ARM_MODE := arm

LOCAL_PATH := $(MY_LOCAL_PATH)
LOCAL_MODULE := ndkDebugModule
LOCAL_SRC_FILES := nftSimple.cpp ARMarkerNFT.c trackingSub.c

# Make sure DEBUG is defined for debug builds. (NDK already defines NDEBUG for release builds.)
ifeq ($(APP_OPTIM),debug)
    LOCAL_CPPFLAGS += -DDEBUG
endif

LOCAL_C_INCLUDES += $(ARTOOLKIT_DIR)/../include/android $(ARTOOLKIT_DIR)/../include
LOCAL_LDLIBS += -llog -lGLESv1_CM -lz
LOCAL_WHOLE_STATIC_LIBRARIES += ar
LOCAL_STATIC_LIBRARIES += ar2 kpm util eden argsub_es armulti aricp jpeg arvideo cpufeatures
#LOCAL_SHARED_LIBRARIES += $(CURL_LIBS)
LOCAL_STATIC_LIBRARIES += $(CURL_LIBS)

include $(BUILD_SHARED_LIBRARY)

$(call import-module,android/cpufeatures)

This build is working properly. Now i am trying to convert this to the android experimental gradle file in order to be able to debug it. Well for now I am having this state:

apply plugin: 'com.android.model.application'

model {
    android {
        compileSdkVersion = 23
        buildToolsVersion = "23.0.3"

        defaultConfig.with {
            applicationId = "com.nomad5.ndkdebug"
            minSdkVersion.apiLevel = 16
            targetSdkVersion.apiLevel = 23
            versionCode = 1
            versionName = "0.1"
        }
    }
    /*
    * native build settings
    */
    android.ndk {
        moduleName = "ndkDebugModule"
        cppFlags.add("-I./../../../../../artoolkit5/include/ ")
    }

    android.buildTypes {
        release {
            minifyEnabled = false
            proguardFiles.add(file('proguard-rules.txt'))
        }
        debug {
            debuggable = true
            ndk.with {
                debuggable = true
            }
        }
    }
}

/**
 * The android native sources
 */
android.sources.main {
    jni {
        exportedHeaders {
            srcDirs = [arRoot.absolutePath + "/include",
                       arRoot.absolutePath + "/android/jni/curl/include"]
        }
        source {
            /* we set this to NOT automatically compile everything */
            srcDirs = ["src/main"]
            include "jni/nativeCodeA.cpp"
            include "jni/nativeCodeB.cpp"

        }
        dependencies {
            library "lib_ar2" linkage "static"
            library "lib_kpm" linkage "static"
            library "lib_util" linkage "static"
            library "lib_eden" linkage "static"
            library "lib_argsub_es" linkage "static"
            library "lib_armulti" linkage "static"
            library "lib_ar" linkage "static"
            library "lib_aricp" linkage "static"
            library "lib_jpeg" linkage "static"
            library "lib_arvideo" linkage "static"
            library "lib_cpufeatures" linkage "static"
            library "lib_curl" linkage "static"
        }
    }
    jniLibs {
        source {
            srcDirs = [arRoot.absolutePath + "/include",
                       arRoot.absolutePath + "/android/jni/curl/include"]
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile project(':aRBaseLib')
    compile 'com.android.support:appcompat-v7:23.4.0'
}

The problem with the gradle ndk build is, that in my files (nativeCodeA.cpp for example) all includes that are in ../../../../../artoolkit5/android are not found. So all of the

#include <AR/ar.h>
#include <AR/arMulti.h>
#include <AR/video.h>
...

are not found.

How can I add a folder to the gradle aware ndk build like LOCAL_C_INCLUDES does in the makefile. And how can i specify specific files to compile like LOCAL_SRC_FILES in the makefile. (How does gradle know the files even if not specifying those explicitly?)

By the way i am using

distributionUrl=https\://services.gradle.org/distributions/gradle-2.8-all.zip

with

'com.android.tools.build:gradle-experimental:0.4.0'

Just a guess but the project working directory is probably different with the different build systems. To check this, change your relative include path(s) to absolute path(s). If this works, then try amending the number of `../`s in the relative paths. — Richard Critten, Sep 15 '16 at 19:29
well, as you see in the comments, i have tried it with absolute paths too — Martin Mlostek, Sep 15 '16 at 19:43
How did you end up setting **NDEBUG** in gradle-experimental? — IgorGanapolsky, Sep 22 '16 at 18:32
i got it up and running, see my answer below. if there is anything unclear, feel free to ask — Martin Mlostek, Sep 22 '16 at 19:50

Martin Mlostek · Accepted Answer · 2016-09-22T19:49:30.297

Okay, I researched a lot and found some examples that are working. First of all you have to use the latest gradle experimantal plugin like this in your root build.gradle

'com.android.tools.build:gradle-experimental:0.4.0'

Then your gradle file will look like this

apply plugin: 'com.android.model.application'

/**
 * The ar.dir in relative format
 */
def arRoot = new File("../artoolkit5")
def arPath = arRoot.absolutePath + '/android/obj/local/'
def curlPath = arRoot.absolutePath + '/android/jni/curl/libs/'

/**
 * The main experimental model
 */
model {

    /**
     * Android APK values
     */
    android {
        compileSdkVersion = 23
        buildToolsVersion = "23.0.3"

        defaultConfig.with {
            applicationId = "com.nomad5.ndkdebug"
            minSdkVersion.apiLevel = 16
            targetSdkVersion.apiLevel = 23
            versionCode = 1
            versionName = "0.1"
        }
    }

    /**
     * The build types
     */
    android.buildTypes {
        release {
            minifyEnabled = false
            proguardFiles.add(file('proguard-rules.txt'))
        }
        debug {
            debuggable = true
            ndk.with {
                debuggable = true
            }
        }
    }

    /**
     * All statically linked libs
     */
    repositories {
        libs(PrebuiltLibraries) {
            lib_ar2 {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libar2.a")
                }
            }
            lib_kpm {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libkpm.a")
                }
            }
            lib_util {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libutil.a")
                }
            }
            lib_eden {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libeden.a")
                }
            }
            lib_argsub_es {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libargsub_es.a")
                }
            }
            lib_armulti {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libarmulti.a")
                }
            }
            lib_ar {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libar.a")
                }
            }
            lib_aricp {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libaricp.a")
                }
            }
            lib_jpeg {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libjpeg.a")
                }
            }
            lib_arvideo {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libarvideo.a")
                }
            }
            lib_cpufeatures {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${arPath}${targetPlatform.getName()}/libcpufeatures.a")
                }
            }
            lib_curl {
                binaries.withType(StaticLibraryBinary) {
                    staticLibraryFile = file("${curlPath}${targetPlatform.getName()}/libcurl.a")
                }
            }
        }
    }

    /*
    * native build settings
    */
    android.ndk {
        moduleName = "ndkDebugModule"
        toolchain = "clang"
        stl = "c++_static"
        platformVersion = 15
        cppFlags.addAll(["-frtti",
                         "-fexceptions",
                         "-I${file(arRoot.absolutePath + "/include")}".toString(),
                         "-I${file(arRoot.absolutePath + "/android/jni/curl/include")}".toString()
        ])
        ldLibs.addAll(['android',
                       'log',
                       'z',
                       'GLESv1_CM'])
        abiFilters.addAll(["armeabi-v7a",
                           /*"arm64-v8a",*/
                           "x86",
                           /*"x86_64"*/])
    }

    /**
     * The android native sources
     */
    android.sources.main {
        jni {
            exportedHeaders {
                srcDirs = [arRoot.absolutePath + "/include",
                           arRoot.absolutePath + "/android/jni/curl/include"]
            }
            source {
                /* we set this to NOT automatically compile everything */
                srcDirs = ["src/main"]
                include "jni/nativeCodeA.cpp"
                include "jni/nativeCodeB.cpp"

            }
            dependencies {
                library "lib_ar2" linkage "static"
                library "lib_kpm" linkage "static"
                library "lib_util" linkage "static"
                library "lib_eden" linkage "static"
                library "lib_argsub_es" linkage "static"
                library "lib_armulti" linkage "static"
                library "lib_ar" linkage "static"
                library "lib_aricp" linkage "static"
                library "lib_jpeg" linkage "static"
                library "lib_arvideo" linkage "static"
                library "lib_cpufeatures" linkage "static"
                library "lib_curl" linkage "static"
            }
        }
        jniLibs {
            source {
                srcDirs = [arRoot.absolutePath + "/include",
                           arRoot.absolutePath + "/android/jni/curl/include"]
            }
        }
    }
}

/**
 * The Java dependencies
 */
dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile project(':aRBaseLib')
    compile 'com.android.support:appcompat-v7:23.4.0'
    compile 'com.android.support:design:23.4.0'
}

/**
 * Dynamically add libs to the linker
 */
class SampleMigrationRuleSource extends RuleSource {

    @Mutate
    void injectArmeabiV7aDebugLinkerFlags(
            @Path('tasks.linkNdkDebugModuleArmeabi-v7aDebugSharedLibrary')
                    Task linkTask) {
        injectLinkerFlags(linkTask, 'armeabi-v7a', 'debug')
    }

    @Mutate
    void injectArmeabiV7aReleaseLinkerFlags(
            @Path('tasks.linkNdkDebugModuleArmeabi-v7aReleaseSharedLibrary')
                    Task linkTask) {
        injectLinkerFlags(linkTask, 'armeabi-v7a', 'release')
    }

    @Mutate
    void injectX86DebugLinkerFlags(
            @Path('tasks.linkNdkDebugModuleX86DebugSharedLibrary')
                    Task linkTask) {
        injectLinkerFlags(linkTask, 'x86', 'debug')
    }

    @Mutate
    void injectX86ReleaseLinkerFlags(
            @Path('tasks.linkNdkDebugModuleX86ReleaseSharedLibrary')
                    Task linkTask) {
        injectLinkerFlags(linkTask, 'x86', 'release')
    }

    private void injectLinkerFlags(linkTask, arch, buildType) {

        def arRoot = new File("../artoolkit5")
        def arPath = arRoot.absolutePath + '/android/obj/local/'
        def curlPath = arRoot.absolutePath + '/android/jni/curl/libs/'

        linkTask.doFirst {
            // We are pretty clueless on this one but it is needed
            if (arch.equals('arm64-v8a')) {
                properties["linkerArgs"].add("-fuse-ld=gold")
            }

            properties["linkerArgs"].addAll([
                    "-l${arPath}/${arch}/libar.a".toString(),
                    "-l${arPath}/${arch}/libar2.a".toString(),
                    "-l${arPath}/${arch}/libutil.a".toString(),
                    "-l${arPath}/${arch}/libkpm.a".toString(),
                    "-l${arPath}/${arch}/libeden.a".toString(),
                    "-l${arPath}/${arch}/libargsub_es.a".toString(),
                    "-l${arPath}/${arch}/libarmulti.a".toString(),
                    "-l${arPath}/${arch}/libaricp.a".toString(),
                    "-l${arPath}/${arch}/libjpeg.a".toString(),
                    "-l${arPath}/${arch}/libarvideo.a".toString(),
                    "-l${arPath}/${arch}/libcpufeatures.a".toString(),
                    "-l${curlPath}/${arch}/libcurl.a".toString(),
            ])
        }
    }
}

apply plugin: SampleMigrationRuleSource

Android gradle ndk jni build with external library & native debugging (ARToolkit)

1 Answers1