I have an NDK-based project (written mostly on C++) and I want to split its sources into two parts: "lib" (to be shared with other projects) and "app" (files specific to current project).
Now my Android.mk looks as follows:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := MyProj
MY_LIB_SOURCES := \
libfile1.cpp \
libfile2.cpp
MY_APP_SOURCES := \
appfile1.cpp \
appfile2.cpp
LOCAL_SRC_FILES += $(MY_LIB_SOURCES)
LOCAL_SRC_FILES += $(MY_APP_SOURCES)
LOCAL_STATIC_LIBRARIES := android_native_app_glue
include $(BUILD_SHARED_LIBRARY)
$(call import-module,android/native_app_glue)
The only reason for splitting is that I want to add/remove lib source file once, because now I have to change Android.mk for all projects which need sources from MY_LIB_SOURCES.
Do I have to create a separate project that would produce a shared library? Or should it be a static library? Or maybe it's possible to just #include somehow file that enumerates MY_LIB_SOURCES into Android.mk of each app?
We usually create a separate folder for library sources, e.g.
project
jni
appfile1.cpp
appfile2.cpp
Android.mk (1)
my_lib
libfile1.cpp
libfile2.cpp
Android.mk (2)
This is the first (application) Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := MyProj
MY_APP_SOURCES := \
appfile1.cpp \
appfile2.cpp
LOCAL_SRC_FILES += $(MY_APP_SOURCES)
LOCAL_STATIC_LIBRARIES := android_native_app_glue
LOCAL_STATIC_LIBRARIES += MyLib
include $(BUILD_SHARED_LIBRARY)
include $(LOCAL_PATH)/../../my_lib/Android.mk
$(call import-module,android/native_app_glue)
This is the second (library) Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := MyLib
MY_LIB_SOURCES := \
libfile1.cpp \
libfile2.cpp
LOCAL_SRC_FILES += $(MY_LIB_SOURCES)
include $(BUILD_STATIC_LIBRARY)
Using the Andorid.mk name for MyLib is by convention; you could use some other file name, and change the include statement (line 17 of the first Android.mk file) accordingly.
You could also use the same $(call import-module) syntax, like
$(call import-module,my_lib)
But to do so, you must provide a NDK_MODULE_PATH environment variable that includes $(LOCAL_PATH)/../../.
Your library will be rebuilt anew for each app (project) that includes it - either with the first naïve include method, or with $(call import-module) method. You can provide a prebuilt static library, but this is a different story.
You must divide your android.mk in two sections:
LOCAL_PATH := $(call my-dir)
## The lib ##
include $(CLEAR_VARS)
LOCAL_MODULE := my_lib
SRC_LIB := $(wildcard $(LOCAL_PATH)/*.cpp)
LOCAL_SRC_FILES := $(SRC_LIB:$(LOCAL_PATH)/%=%)
include $(PREBUILT_SHARED_LIBRARY)
## The App ##
include $(CLEAR_VARS)
LOCAL_MODULE := my_app
LOCAL_CPP_EXTENSION := .cxx .cpp .cc
LOCAL_SRC_FILES := \
appfile1.cpp \
appfile2.cpp
LOCAL_STATIC_LIBRARIES := android_native_app_glue
LOCAL_SHARED_LIBRARIES := my_lib
LOCAL_LDLIBS += -landroid
include $(BUILD_EXECUTABLE)
$(call import-module,android/native_app_glue)
If you want static library you have only to change include $(PREBUILT_SHARED_LIBRARY) to include $(PREBUILT_STATIC_LIBRARY) and LOCAL_SHARED_LIBRARIES := my_lib to LOCAL_STATIC_LIBRARIES += my_lib
Related
so I'm relatively new to Android-NDK and trying to add an uncompiled c-library to android.
I've downloaded the library's source from here and followed these instructions to create a static library (.a-File) from the downloaded files using ndk-build.
So now I have a folder-structure that looks like this:
-srtp
--include (srtp.h, crypto.h)
--srtp (srtp.c...)
--obj
---local
----armeabi
-----libsrtp_static.a
In my Android-project I want to include srtp.h in a c-file inside my /jni/ folder. I've tried to just add the .a-file to the /jni folder but than it says "srtp.h no such file or direcotry". If I add the entire srtp-folder to the project and include the header with "srtp/include/srtp.h" it compiles but fails to link the source as I get the error "Undefined reference to srtp-function-call"
Here's my Android.mk (parts of it copied from Android.mk within the downloaded source):
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_LDLIBS := -llog
LOCAL_MODULE := ndk1 #name of my project
LOCAL_SRC_FILES := native.c #name of the c-source file
include $(BUILD_SHARED_LIBRARY)
LOCAL_PATH:= /home/dev/programing/srtp
common_SRC_FILES := \
srtp/srtp.c \
srtp/ekt.c \
crypto/cipher/cipher.c \
#...more files like that
common_CFLAGS := \
-DPOSIX -iquote$(LOCAL_PATH)/crypto/include \
-Werror \
-Wno-ignored-qualifiers \
-Wno-sign-compare \
-Wno-missing-field-initializers
common_C_INCLUDES = $(LOCAL_PATH)/include
# For the device
# =====================================================
# Device static library
include $(CLEAR_VARS)
ifneq ($(TARGET_ARCH),x86)
LOCAL_NDK_VERSION := 5
LOCAL_SDK_VERSION := 9
endif
LOCAL_SRC_FILES := libsrtp_static.a
LOCAL_CFLAGS += $(common_CFLAGS)
LOCAL_C_INCLUDES += /home/dev/programing/srtp/include
LOCAL_MODULE:= libsrtp_static
LOCAL_MODULE_TAGS := optional
include $(BUILD_STATIC_LIBRARY)
Any help is greatly appreciated! Thank you very much.
You need to add the reference to libsrtp_static from your lib (ndk1) declaration :
LOCAL_STATIC_LIBRARIES := libsrtp_static
Also, you don't need to copy all the strp sources to your project, only add this to your static prebuilt library definition
LOCAL_EXPORT_C_INCLUDES += /home/dev/programing/srtp/include
This path will then be automatically added to the LOCAL_C_INCLUDES of your library that is using the library.
Are you building libsrtp or just using a prebuilt static library ? If you're using a prebuilt (lib*.a), replace BUILD_STATIC_LIBRARY with PREBUILT_STATIC_LIBRARY and set only the .a as SRC_FILE:
In summary, once libstrp_static.a is built, this should work:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_LDLIBS := -llog
LOCAL_MODULE := ndk1 #name of my project
LOCAL_SRC_FILES := native.c #name of the c-source file
LOCAL_STATIC_LIBRARIES := libsrtp_static
include $(BUILD_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_SRC_FILES := /home/dev/programing/srtp/libsrtp_static.a #check path to libsrtp_static.a
LOCAL_EXPORT_C_INCLUDES += /home/dev/programing/srtp/include
LOCAL_MODULE:= libsrtp_static
LOCAL_MODULE_TAGS := optional
include $(BUILD_STATIC_LIBRARY)
I want to build an shared library. To build it, I need to call another shared library. Here is what I did:
1.Create one Android project,named "BuildLib",and add a new folder "jni" under the project directory. Contents of jni folder:
jni-->Android.mk
-->Application.mk
-->add.cpp
-->add.h add.cpp just do two numbers addition:
add.h:
int add(int a,int b);
add.cpp:
#include "add.h"
int add(int a,int b){
return a+b;}
Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_SRC_FILES := add.cpp
LOCAL_MODULE := add
include $(BUILD_SHARED_LIBRARY)
After build the project,I got libadd.so under directory $(BUILDLIB)/libs/armeabi/.
Create another Android project, named "CallLib". Copy libadd.so and add.h to jni folder, create Android.mk, Application.mk, and call_add.cpp.
Android.mk:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_SRC_FILES := libadd.so
LOCAL_MODULE := add_prebuilt
include $(PREBUILD_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_C_INCLUDES := $(LOCAL_PATH）
LOCAL_SRC_FILES := call_add.cpp
LOCAL_MODULE := native
LOCAL_SHARED_LIBRARIES := add_prebuilt
include $(BUILD_SHARED_LIBRARY)
call_add.cpp:
#include "add.h"
int call_add(){return add(1,2);}
After all above, I build the CallLib project, but got the error:
undefined reference to 'add(int, int)';
I think the libadd.so can not be found, but I don't know how to modify. Does anyone know how I can fix this? Any help will be appreciated.
In your second Android.mk, try replacing the first module with:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_SRC_FILES := libadd.so
LOCAL_MODULE := add_prebuilt
LOCAL_EXPORT_C_INCLUDES := add.h
include $(PREBUILD_SHARED_LIBRARY)
The LOCAL_EXPORT_C_INCLUDES flag should attach the header information to the add_prebuilt module, so it can be linked with your final library.
Just in case anyone needs it:
A bit hackish way to keep the linker happy:
LOCAL_LDLIBS := -llog
or
LOCAL_LDLIBS := -L$(LOCAL_PATH)/lib -lMyStuff
Less hackish:
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := xyz
LOCAL_SRC_FILES += xyz/xyz.c
LOCAL_LDLIBS := -llog
include $(BUILD_SHARED_LIBRARY) # this builds libxyz.so
include $(CLEAR_VARS)
LOCAL_MODULE := abc
LOCAL_SHARED_LIBRARIES := xyz # <=== !!! this makes libabc.so dependent on libxyz.so
LOCAL_SRC_FILES := abc/abc.c
#LOCAL_LDLIBS := ...
include $(BUILD_SHARED_LIBRARY) # this builds libabc.so
I try to set up an Android NDK build based on CMake scripts, which dynamically create the required Android make files. While I can't use the JNI folder structure I split the build process in several separated make scripts:
1st Create root Android.mk file located in project root:
#ANDROID ROOT MAKEFILE
LOCAL_PATH := D:/binrev/repository/bar
include $(CLEAR_VARS)
MY_LOCAL_CFLAGS := -DDEBUG
include D:/binrev/repository/bar/src/Android.mk
2nd Create source Android.mk file in project source folder and perform module build:
$(info "[INFO] Source Makefile invoked")
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := bar
LOCAL_C_INCLUDES:= D:/binrev/repository/bar/include
LOCAL_SRC_FILES := bar.cpp
ifeq (debug,"debug")
MY_LOCAL_CFLAGS := -DDEBUG
endif
ifeq (false,true)
LOCAL_ARM_MODE := arm
endif
LOCAL_EXPORT_C_INCLUDES := D:/binrev/repository/bar/include
LOCAL_LDLIBS := -llog
LOCAL_LDLIBS += -landroid
LOCAL_STATIC_LIBRARIES += foo
ifeq (OFF, ON)
include $(BUILD_SHARED_LIBRARY)
else
include $(BUILD_STATIC_LIBRARY)
endif
Basicly this mechanism works and I could compile my sources, but I fail if I try to include a Prebuild of a library. I tried the following ways to include a pre-build
of a static library (with modified source/include definitions):
include $(CLEAR_VARS)
LOCAL_MODULE := foo
LOCAL_SRC_FILES := lib/android/$(TARGET_ARCH_ABI)/libfoo.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_STATIC_LIBRARY)
1st Prebuild definition in source Android.mk file
2nd Call import-module mechanism and add Prebuild Android.mk file to prebuild-lib
3rd Prebuild definition in root Android.mk file
[Edit:] Here is the snipped of the call-import test which also fail:
$(info "[INFO] Source Makefile invoked")
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := bar
LOCAL_C_INCLUDES:= D:/binrev/repository/bar/include
LOCAL_SRC_FILES := bar.cpp
ifeq (debug,"debug")
MY_LOCAL_CFLAGS := -DDEBUG
endif
ifeq (false,true)
LOCAL_ARM_MODE := arm
endif
LOCAL_EXPORT_C_INCLUDES := D:/binrev/repository/bar/include
LOCAL_LDLIBS := -llog
LOCAL_LDLIBS += -landroid
LOCAL_STATIC_LIBRARIES += foo
ifeq (ON, ON)
include $(BUILD_SHARED_LIBRARY)
else
include $(BUILD_STATIC_LIBRARY)
endif
$(call import-module, external-deps/foo)
In each case the Script with the prebuild-definition is invoked, but the prebuild
is not performed. When my NDK build has been compleded, the prebuild library and
objects are not copied to my obj folder. It seems to me that the prebuild is
completely ignored. But the path to prebuild sources are correct, otherwise the
compile fails with missing file error.
You could get the complete source of this test implementation here:
[Test projects][1]https://sourceforge.net/projects/binrevengine/files/publications/
Hint: The bar project is the project which tries to prebuild the foo project.
The foo project contains the prebuild sources.
The added tests projects could be build by your own using MinGW64 with GCC 4.7/4.8 in handshake with CMake and pre installed NDK (using r8e).
I completly get lost and running out of ideas ...
Thanks for any help.
The Android build system will not build a static library without it being used by a shared library. Just create a dummy shared library that has your static library as a dependency and voila:
include $(CLEAR_VARS)
LOCAL_MODULE := dummy
LOCAL_PATH := $(LOCAL_PATH)
LOCAL_SRC_FILES := dummy.c
LOCAL_STATIC_LIBRARIES := foo
include $(BUILD_SHARED_LIBRARY)
To exclude possible sources of defects I've reduced the Android make file to simplest case without using CMake generator of those files:
LOCAL_PATH := D:/binrev/repository/bar
include $(CLEAR_VARS)
LOCAL_MODULE := foo-prebuilt
LOCAL_SRC_FILES := external-deps/foo/lib/android/$(TARGET_ARCH_ABI)/libfoo.a
include $(PREBUILT_STATIC_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := bar
LOCAL_C_INCLUDES:= D:/binrev/repository/bar/include
LOCAL_C_INCLUDES+= D:/binrev/repository/bar/external-deps/foo/include
LOCAL_SRC_FILES := src/bar.cpp
LOCAL_LDLIBS := -llog
LOCAL_LDLIBS += -landroid
LOCAL_SHARED_LIBRARIES := foo-prebuilt
include $(BUILD_SHARED_LIBRARY)
and:
LOCAL_PATH := D:/binrev/repository/foo
include $(CLEAR_VARS)
LOCAL_MODULE := foo
LOCAL_C_INCLUDES:= D:/binrev/repository/foo/include
LOCAL_SRC_FILES := src/foo.cpp
LOCAL_LDLIBS := -llog
LOCAL_LDLIBS += -landroid
include $(BUILD_STATIC_LIBRARY)
The failure still exists. The prebuild of the foo library is not executed. I also excluded MinGW64 as possible source of defect, if I try to build the project with Windows command line it results in same issue. The shared library is build, but the prebuild is not executed.
I checked my sources and scripts multiple times, but can't find any failure.
Any ideas what could be wrong or missing?
I have three static libraries from a framework that I want to use in my project. These libraries are called libtinySAK_armv7-a.a, libtinyNET_armv7-a.a and libtinyHTTP_armv7-a.a. I have placed them in the same folder as the Android.mkandApplication.mk.
My native code is dependent on them so I want to include them in my shared library.
From what I've read on stackoverflow and google'd I believe the android.mk is supposed to look something like this:
# TINYSAK
include $(CLEAR_VARS)
LOCAL_MODULE := tinySAK
LOCAL_SRC_FILES := libtinySAK_armv7-a.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../doubango/tinySAK/src/
include $(PREBUILT_STATIC_LIBRARY)
# TINYNET
include $(CLEAR_VARS)
LOCAL_MODULE := tinyNET
LOCAL_SRC_FILES := libtinyNET_armv7-a.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../doubango/tinyNET/src/
include $(PREBUILT_STATIC_LIBRARY)
# TINYHTTP
include $(CLEAR_VARS)
LOCAL_MODULE := tinyHTTP
LOCAL_SRC_FILES := libtinyHTTP_armv7-a.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/../../../doubango/tinyHTTP/include/
include $(PREBUILT_STATIC_LIBRARY)
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := libtest
LOCAL_SRC_FILES := \
../../test/stack.cpp \
../../test/main.cpp
LOCAL_C_INCLUDES := \
$(LOCAL_PATH)/../../test/include/ \
$(LOCAL_PATH)/../../../doubango/tinyHTTP/include/ \
$(LOCAL_PATH)/../../../doubango/tinySAK/src/ \
$(LOCAL_PATH)/../../../doubango/tinyNET/src/
LOCAL_STATIC_LIBRARIES := \
tinySAK \
tinyNET \
tinyHTTP
include $(BUILD_SHARED_LIBRARY)
My Application.mk:
APP_STL := stlport_static
APP_ABI := armeabi-v7a
The error I get upon compilation("ndk-build" from project dir) is
jni/Android.mk:tinySAK: LOCAL_SRC_FILES points to a missing file
And I suppose the other 2 libraries also fail. Why cannot it find them?
Besides that, is there any other errors I've made in the makefile?
Thanks
Nevermind, I solved it.
I declared the "LOCAL_PATH" in the beginning of the make-file only. Otherwise it would look for the libs in the ndk-folders.
Try LOCAL_LDLIBS instead of LOCAL_SRC_FILES.
i'm wrapping a native API to Android by NDK.
But when building it don't find the header files.
I have the following structure.
project/jni
Android.mk
LOCAL_PATH := $(call my-dir)
include $(call all-subdir-makefiles)
LOCAL_PATH :=/home/marcos/dev/workspace/rmsdk.native.wraper/jni
include $(CLEAR_VARS)
LOCAL_LDLIBS := -llog
LOCAL_MODULE := ndk1
LOCAL_SRC_FILES := native.c DelegateDRMProcessorClient.cpp
LOCAL_STATIC_LIBRARY := adept cryptopenssl dp expat fonts hobbes jpeg mschema png t3 xml zlib
include $(BUILD_SHARED_LIBRARY)
project/jni/prereqs/
Android.mk (Used to call all subdirs Android.mk files)
LOCAL_PATH := $(call my-dir)
include $(call all-subdir-makefiles)
include $(CLEAR_VARS)
project/jni/prereqs/%lib%/
Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE :=dp
LOCAL_SRC_FILES :=libdp.a
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include
include $(PREBUILT_STATIC_LIBRARY)
And there's a include folder on each %lib% folder.
When using ndk-build I get a
"/home/marcos/dev/workspace/rmsdk.native.wraper/jni/DelegateDRMProcessorClient.h:18:20: error: dp_all.h: No such file or directory"
Anyone knows how to include these header to be available to the compiler?
I solve it, getting all the headers in a folder and including the following line in the Android.mk
LOCAL_C_INCLUDES := $(LOCAL_PATH)/include-all
This works, but not looks like the best approach.
I'm a bit late to this party, but ran into the same issue and might have an answer for your comment:
"This works, but not looks like the best approach"
There;s a sample in the NDK called "module-exports"
It shows how to construct an Android.mk file which respects header files living in their proper directories and not all dumped into a single include directory.
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE := foo
LOCAL_SRC_FILES := foo/foo.c
LOCAL_CFLAGS := -DFOO=2
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/foo
LOCAL_EXPORT_CFLAGS := -DFOO=1
LOCAL_EXPORT_LDLIBS := -llog
include $(BUILD_STATIC_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := bar
LOCAL_SRC_FILES := bar/bar.c
LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/bar
LOCAL_STATIC_LIBRARIES := foo
include $(BUILD_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := zoo
LOCAL_SRC_FILES := zoo/zoo.c
LOCAL_SHARED_LIBRARIES := bar
include $(BUILD_SHARED_LIBRARY)
Years later...
To export the include directory instead of individual files, I use the following:
LOCAL_EXPORT_C_INCLUDE_DIRS := $(MY_DIRECTORY_PATH)
For example, for the above question the export for "foo" would look like:
LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/foo
For new people's convenience, I just want to add that move all your header files in folder which is referred by LOCAL_C_INCLUDES := $(LOCAL_PATH) and then save android.mk and restart eclipse. After trying all the above solutions, that worked for me.