Can somebody help me write Android.mk for LibXtract or point me in correct directoin?
Here is source for lib - https://github.com/jamiebullock/LibXtract.git
Or mayby there is a way to use linux generated shared objects in Android?
Especially for bigger established projects, crafting Android.mk files is quite an effort. More so, if you are not familiar with Android NDK build architecture whose understanding requires digging deep into the documentation and Android NDK make files. I would suggest trying to use existing make files by setting CC to point to your NDK tool chain, and CFLAGS += -sysroot $(SYSROOT) where SYSROOT=${NDK_INSTALL_DIR}/platforms/android-<level>/arch-<arch>/ (depending on targeted Android API version and architecture). Even without knowing about your library, I would bet you should have good chance of success this way. Android NDK documentation (${NDK_INSTALL_DIR}/doc/STANDALONE-TOOLCHAIN.html) details the use of independent tool chain and also instructs how to create a standalone tool chain that will not require the use of -sysroot argument to xxx-gcc.
If you decide to use Android.mk instead, you might check existing projects -CSipSimple comes to my mind (PJSIP converted from standard form GNU make files).
Important is to create the shared objects using Android tool chains. It is possible to build them outside of your application source tree, and then just copy the shared objects into the package source libs/<architecture>/ directory.
Integration with your build system depends on details that are not known (including how smooth you desire this whole integration to be e.g. because of other people working with the same project). If you are creating an application from command line, the easiest would be to have GNU make file or shell script in the package root directory ensure libXtract.so and your application package is up-to-date by calling libXtract make file and ant to build and pack your Java application. If you are using ant there should be a way to specify using make to take care of libXtract.so. I am not sure if eclipse is completely relying on ant for building an application to know if this would be enough for enabling complete build by clicking mouse buttons from within eclipse, too.
The answer to this question says you could use cmake script to build Android.mk files - I have not tried this approach.
Related
I need to compile libmysqlclient and librtlstr for Android (in fact I could find rtlsdr, but since I need mysqlclient the issue is still there).
I followed several guides but most of them present the instruction written here http://mortoray.com/2012/08/21/android-ndk-cross-compile-setup-libpng-and-freetype/
Anyway, the package I download did not contain any configure file so I don't know how to continue.
Because the purpose of this file should only be the creation of the makefile, maybe there is a way solve this.
So my questions are:
1) Is this the right approach? Are there others easier?
2) Does a general configure file exist so that I can download and use it?
3)If not, how does the makefile has to be written? This way I should be able to overcome the abscence of configure file
I need those libraries to port a c code (which needs them) to android building an executable that I'll run on my phone (so I already have the standalone toolchain from the NDK), if it helps
1) This is right approach (may be a little bit simplified, I'm using more steps to build) for libraries, which use automake. Much easier, if library uses Cmake (must contain CMakeLists.txt), because you need only NDK. Example: cmake -DANDROID_NDK=path/to/ndk -DCMAKE_TOOLCHAIN_FILE=$NDK/build/cmake/android.toolchain.cmake -DANDROID_ABI=armeabi-v7a -DANDROID_PLATFORM=android-21 ..
2) No, also you need provide additional files (for example, Makefile.in)
3) This libraries have to use one of tools such CMake, automake etc, just Makefile or project for some IDE. So, try to find out, what of this use your libraries
My server needs to keep building a large amount of Android projects. All of them are almost identical except for minor change on manifest.xml or any resource file (if it's better for the task) for each build. To reduce cost and improve efficiency, I try to implement incremental build. My planned procedures are:
after the first successful build, skip all the previous
procedures (aapt to generate R.java, adle to make java, etc.)
directly call aapt to make resource files, e.g., *.ap_
call apkbuilder to make classes.dex and usigned.apk
make signed.apk
So my question is whether the above solution is possible? And any clue about how to implement it?
This isn't necessarily a solution for your particular requirements but perhaps it will provide you with some useful pointers.
I have an Antlib that I use for building Android projects. You probably won't want to use it yourself as it has some drawbacks, but it should serve as an example of how to perform the various steps to build an Android app using Ant. In particular, it shows how to call the various Android SDK tools from Ant and how to use the Ant uptodate task and Ant's if and unless attributes to avoid processing files that haven't changed.
The source for the Android Ant macros is here (the Antlib documentation might help you to make sense of what it's doing).
I want to write an Android application that is able to display list of exported functions by a shared library (.so).
nm/objdump/readelf tool is only available for Windows/Linux. So I have thought about compiling platfor_external_elfutils to get a toolchain with nm or objdump tool.
However, this is not a good solution considering the big dependencies the toolchain may cause (can be up to xx MB).
I want to ask if there is any available simple code to achieve the purpose without having to compile and attache the whole toolchain in my app.
This is probably too late for the original poster, but libelf can be built as a static library (libelf.a) from Android sources, at least since JB4.2. Just use
make libelf
In the main directory to build it.
If someone knows how to build it as a dynamic library/shared object that would be much appreciated.
You can use libelf library (from elftoolchain - it's BSD licensed) to parse the binary. libelf comes with source for elfdump utility that dumps various information about ELF file including export list. Just strip out the source you don't need and you're ready. Executable for this won't take more than 100KB.
I wish to back port the Android RTP APIs introduced in version 3.1(Honeycomb) to earlier versions. I downloaded the source of version 4.0 and found that it these APIs had both java and native code. In order to build the native code with the NDK, certain shared libraries are required.
According the Android.mk file, these are libnativehelper, libcutils, libutils, and libmedia. Though the source of all of these are present in the source code, building them was difficult. Each required many other shared libraries. For eg, libmedia requires these shared libraries: libui, libcutils, libutils, libbinder, libsonivox, libicuuc, libexpat, libcamera_client, libstagefright_foundation, libgui and libdl.
So my question is, is there some way of obtaining the original 4 shared libs? Does it involve building the entire source?
Say I need to build a piece of native code which is going to use standard Android shared libraries such as libutils, libcutlis, libmedia. I would perform following steps:
Install AOSP repository with target version.
Add my source code to appropriate directories under ./frameworks/base. In your case it might be easier to create a separate folder and put proper Android.mk of course.
You might get compile errors if required functions from those standard shared libraries are not present in the previous version.
When you build the code as part of AOSP it will build required libraries and link them for you automatically.
P.S. To accomplish that you're better to use a Linux-based build host.
using cygwin terminal, build native part i.e. jni folder. To build using cygwin, goto jni folder using cygdrive command. Then type ndk-build. After successful completion, shared libraries i.e. .so files will be created in libs folder.
I can understand your problem, you can pull the libraries from /system/lib of device or emulator. But you need a system permission. But you can do it by installing application.
Otherwise build your source code on linux platfor. Building process is very easy, just using 2 or 3 command. First time it is needed long time to build. After that you need very short time to build, it will build only according to the timestamp of modified code.
Please have a look here
I am interested in integrating Scala (or some other non-Java JVM-language) into the android platform. I am not referring to writing an android application with Scala, that I did early early on, but actually hooking into the build process that builds the android platform source tree. I imagine this will be a matter of hooking into the makefiles and such. Does anyone have insight into this?
What I have so far:
The platform source treefrom git://android.git.kernel.org/platform/manifest.git built in its virgin form, guided by "[Download and build the Google Android][1]"
build/core/combo/scalac.mk # Configures scala compiler related variables, included by config.mk
Added definitions in build/core/definitions.mk for an all-subdir-scala-files and an all-scala-files-under
Added definition in definitions.mk to build scala files such that they are included in the package
What's left:
Include scala-library.jar
Ensure changes to -bootclasspath has not broken anything
Figure out how to handle case where scala classes depend on java classes and visa versa
Major cleanup of code
Testing!
Figure out what to do (other than just posting them here) with the changes I've made
Looks like I'm almost there!!!
Some notes from the past
Latest: I have found where the Java source files are compiled! In definitions.mk, see 'define transform-java-to-classes.jar'. The latest idea is to write a transform-scala-to-classes definition and then have it store those classes in the directly that gets packaged. I will call transform-scala-to-class right before this step in transform-java-to-classes.jar. Support for eclipse and cygwin will for now be dropped as it clutters up the code with workarounds and therefore increases my chances of failure.
The build process starts out by the root Makefile running build/core/main.mk
build/core/main.mk includes build/core/config.mk which includes build/core/combo/javac.mk which sets HOST_JAVAC, TARGET_JAVAC, and COMMON_JAVAC. COMMON_JAVAC is the "Java compiler command with common arguments," by the look of it the other two variables get these values by default, unless in a special environment (openjdk or eclipse). COMMON_JAVAC is not used outside this file. The other two are only used in build/core/definitions.mk.
build/core/java_library.mk (included by config.mk) seems to only be concerned with building jars. This is out of the scope of us caring. Any interaction with jars presupposes class files which presuppose that we were already successful in building our scala files.
There are checks in main.mk regarding the version of java. We will ignore these and assume that our version of scala is compatible. Right now (in combo/scalac.mk) I am using the same --target arg used in javac.mk. This should perhaps be stored in a variable.
main.mk also includes build/core/definitions.mk which in turns defines some useful functions. The one we care about here is all-java-files-under and all-subdir-java-files. The latter is used in Android.mk files to find java files. The former is used in the implementation of the latter. I will write Scala equivalents of them.
To figure out how the build process works, I am now running make with -n and others. I got this idea from the stackoverflow article "[Tool for debugging makefiles][2]". I am also investigating debugging with remake.
build/core/{config.mk, definitions.mk} gives us light as to which make files/commands are used to do what.
As a possible way of hacking in support on a per project bases, additional code could most likely be added to the project's Android.mk file. From platform/build/core/build-system.html we read "Android.mk is the standard name for the makefile fragments that control the building of a given module. Only the top directory should have a file named "Makefile"." You could create a new target like "scala-build" and run that (make PackageName scala-build) before the final make. One could perhaps also hide it sneakily in a variable assignment, mitigating the need for a target to be called explicitly.
Another way (far far more hackish) is to hijack the command being used for javac. This is set in build/core/combo/javac.mk. Your project's Android.mk will have to include *.scala files in LOCAL_SRC_FILES along with the *.java files.
Guys on reddit say, there's a tutorial on integration Scala into Android with ant here.