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cross compile c program for android

I have a c program that uses -lpcap, -lm, and -lpthread. I see the libraries in /usr/arm-linuxgnueabi/lib/. However, if I compile using the command
arm-linux-gnueabi-gcc -static *.c -L/usr/arm-linux-gnueabi/lib/ -lpcap -lm -lpthread -o dumps/forandroid
It gives the following error:
/usr/lib/gcc-cross/arm-linux-gnueabi/4.7/../../../../arm-linux-gnueabi/bin/ld: cannot find crt1.o: No such file or directory<br>
/usr/lib/gcc-cross/arm-linux-gnueabi/4.7/../../../../arm-linux-gnueabi/bin/ld: cannot find crti.o: No such file or directory<br>
/usr/lib/gcc-cross/arm-linux-gnueabi/4.7/../../../../arm-linux-gnueabi/bin/ld: cannot find -lpcap<br>
/usr/lib/gcc-cross/arm-linux-gnueabi/4.7/../../../../arm-linux-gnueabi/bin/ld: cannot find -lm<br>
/usr/lib/gcc-cross/arm-linux-gnueabi/4.7/../../../../arm-linux-gnueabi/bin/ld: cannot find -lpthread
/usr/lib/gcc-cross/arm-linux-gnueabi/4.7/../../../../arm-linux-gnueabi/bin/ld: cannot find -lc<br>
collect2: error: ld returned 1 exit status
How can I give the library path properly? I am trying to compile the program for android emulator running android 5.1. I am using mint 17.2 64 bit amd machine.

I solved the problem using ndk toolchain. I compiled libpcap for arm-linux and used the library. The following command does the job:
arm-linux-androideabi-gcc --sysroot=/home/shahrear/Android/ndk/platforms/android-21/arch-arm -fpie -fpic -I./pcap -I. *.c -L./lib -pie -lm -lpcap -o dumps/forandroid

statically linking c file with android bionic c library

I just wrote a small c file and its header file.
dev_access.c and dev_access.h
I want to link it to the bionic library in android and create a statically/dynamically linked archive file.
My files are in /home/preetam/mydev/
The android sources are in /home/preetam/android_source
The following is my current makefile
CROSS := /home/preetam/bin/CodeSourcery/arm2010/Sourcery_G++_Lite/bin/arm-none-linux-gnueabi
CC := $(CROSS)-gcc
INC_DIR := /home/preetam/android_source/bionic/libc
CFLAGS := -Wall -c -I$(INC_DIR)/include
android_hal: dev_access.o
${CC} ${CFLAGS} dev_access.c -o dev_access.a
clean:
rm -f *.o dev_access.a
I am not sure whats going wrong but header files are not linking and some missing and redefinition errors are coming up.
The following is the Console output:
/home/preetam/bin/CodeSourcery/arm2010/Sourcery_G++_Lite/bin/arm-none-linux-gnueabi-gcc -c -Wall -I/home/preetam/android_source/bionic/libc/include -static -c -o dev_access.o dev_access.c
In file included from /home/preetam/android_source/bionic/libc/include/stdio.h:42,
from dev_access.c:1:
/home/preetam/android_source/bionic/libc/include/sys/_types.h:40: fatal error: machine/_types.h: No such file or directory
compilation terminated.
make: *** [dev_access.o] Error 1
First of all, Is my Makefile correct?
Whats the proper way to link your programs with bionic libc ?
How to make the final object an archive?

You should be using these include paths for bionic:
libc/arch-$ARCH/include
libc/include
libc/kernel/common
libc/kernel/arch-$ARCH
ar might have some switches for it...
EDIT: The switch is cr
ar -crv <libname> <source_object>

How to use arm-linux-androideabi compiler

I wonder how to use arm-linux-androideabi compiler.
That compiler is on android-ndk tool.
There is ndk-build tool on android-ndk tool. To compile ethercat stack, I need only arm-linux-androideabi compiler.
But, I saw this message.
root#ubuntu:/opt/android/android-ndk-r9c/jni# arm-linux-androideabi-gcc -o test test.c
/opt/android/android-ndk-r9c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: error: cannot open crtbegin_dynamic.o: No such file or directory
/opt/android/android-ndk-r9c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: error: cannot open crtend_android.o: No such file or directory
/opt/android/android-ndk-r9c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: error: cannot find -lc
/opt/android/android-ndk-r9c/toolchains/arm-linux-androideabi-4.6/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.6/../../../../arm-linux-androideabi/bin/ld: error: cannot find -ldl
collect2: ld returned 1 exit status
How am I supposed to do this?

You need to let the compiler know where to look for these files.
Try using:
arm-linux-androideabi-gcc --sysroot=/opt/android/android-ndk-r9c/platforms/android-19/arch-arm -o test test.c
where 19 is android API level you want to use. You can find more info on docs/STANDALONE-TOOLCHAIN.html in your ndk dir.

Building native library with standalone toolchain android arm

I am trying to build libraw as a Android shared library. It looks the lib is too complex to use with Android.mk etc, or better: I am not capable yet of doing that.
I tried the route of using a standalone toolchain from the NDK, but I am getting stuck when compiling this lib.
This is the path I take to compile the lib. Please point out if I am making obvious errors:
I downloaded the ndk.
ran: make-standalone-toolchain.sh
Added the bin folder of that standalone toolchain as first item in my PATH.
Ran ./configure with --host=arm-linux-androideabi. This succeeded
Ran make, here it crashed very fast.
LibRaw-0.14.4$ make
depbase=`echo internal/dcraw_common.lo | sed 's|[^/]*$|.deps/&|;s|\.lo$||'`;\
/bin/bash ./libtool --tag=CXX --mode=compile arm-linux-androideabi-g++ -DPACKAGE_NAME=\"LibRaw\" -DPACKAGE_TARNAME=\"libraw\" -DPACKAGE_VERSION=\"0.14.4\" -DPACKAGE_STRING=\"LibRaw\ 0.14.4\" -DPACKAGE_BUGREPORT=\"info#libraw.org\" -DPACKAGE_URL=\"http://www.libraw.org\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -DLT_OBJDIR=\".libs/\" -I. -I/usr/local/include -g -O2 -MT internal/dcraw_common.lo -MD -MP -MF $depbase.Tpo -c -o internal/dcraw_common.lo internal/dcraw_common.cpp &&\
mv -f $depbase.Tpo $depbase.Plo
libtool: compile: arm-linux-androideabi-g++ -DPACKAGE_NAME=\"LibRaw\" -DPACKAGE_TARNAME=\"libraw\" -DPACKAGE_VERSION=\"0.14.4\" "-DPACKAGE_STRING=\"LibRaw 0.14.4\"" -DPACKAGE_BUGREPORT=\"info#libraw.org\" -DPACKAGE_URL=\"http://www.libraw.org\" -DSTDC_HEADERS=1 -DHAVE_SYS_TYPES_H=1 -DHAVE_SYS_STAT_H=1 -DHAVE_STDLIB_H=1 -DHAVE_STRING_H=1 -DHAVE_MEMORY_H=1 -DHAVE_STRINGS_H=1 -DHAVE_INTTYPES_H=1 -DHAVE_STDINT_H=1 -DHAVE_UNISTD_H=1 -DHAVE_DLFCN_H=1 -DLT_OBJDIR=\".libs/\" -I. -I/usr/local/include -g -O2 -MT internal/dcraw_common.lo -MD -MP -MF internal/.deps/dcraw_common.Tpo -c internal/dcraw_common.cpp -fPIC -DPIC -o internal/.libs/dcraw_common.o
internal/dcraw_common.cpp: In member function 'void LibRaw::read_shorts(ushort*, int)':
internal/dcraw_common.cpp:119: error: 'swab' was not declared in this scope
internal/dcraw_common.cpp: In member function 'void LibRaw::write_ppm_tiff()':
internal/dcraw_common.cpp:9235: error: 'swab' was not declared in this scope
make: *** [internal/dcraw_common.lo] Error 1
I doubt this error message is helpfull here at stackoverflow, but I am left wondering if I should have applied some additional flags or configuration to get this to work?
Note that I am able to compile this lib succesfully if just compiling for my system without crosscompiling. (linux 32bit).
When I am looking to a instruction for building GDAL for Android (here), it uses a additional setting of LIBS="-lsupc++ -lstdc++". This links the STL and C++ exceptions?
However, when I set those before running my configure I get immediately errors like:
configure:3018: checking whether the C++ compiler works
configure:3040: arm-linux-androideabi-g++ conftest.cpp -lsupc++ -lstdc++ >&5
/tmp/android-chain/bin/../lib/gcc/arm-linux-androideabi/4.4.3/../../../../arm-linux-androideabi/bin/ld: cannot find -lsupc++
collect2: ld returned 1 exit status
So, I am a bit stuck. Someone an idea?

I had to add an implementation of the swab function, since the NDK does not have that one.
Afterwards this compiled fine (but I used the crystax ndk).
A better way toolwise was to just use a Android.mk file and use ndk-build to compile it.

Linker error from the bottom of your question occurs because make-standalone-toolchain.sh from NDK r7 creates incomplete toolchain (it misses some libraries including libsupc++.a). I recommend you try making a toolchain from one of previous NDK releases (r6b should be fine).

Using native C Kiss_fft.c to calculate fft in android

My goal is to compile the kiss_fft libraries to use in JNI for android development.
However to begin with, I am attempting to just use the kiss_fft libraries on my linux machine in C.
when using Kiss_fft.c or Kiss_fftr.c from Kiss_fft (Kissfft
)to calculate the DFT. How exactly do you compile their libraries into your own file. In the top of my source C file, I #include kiss_fft.h and #include kiss_fftr.h, and also either place the kiss_fft souce code in my project root directory or in /usr/include/ in linux, then I compile with a makefile similar to this one:
#Makefile
#ARGS = -g -ansi -pedantic -Wall -Werror -O1
ARGS = -g -lsndfile -O1 -lm
FILES = spec_subv4.o kiss_fftr.o kiss_fft.o
spec_sub: $(FILES)
gcc $(ARGS) $(FILES) -o spec_sub
spec_subv4.o: spec_subv4.c
gcc -lsndfile $(ARGS) -c spec_subv4.c -o spec_subv4
kiss_fftr.o: kiss_fftr.c kiss_fftr.h kiss_fftr.h _kiss_fft_guts.h
gcc $(ARGS) -c kiss_fftr.c -o kiss_fftr
kiss_fft.o: kiss_fft.c _kiss_fft_guts.h
gcc $(ARGS) -c kiss_fftr.c -o kiss_fft
Looking through all the kiss_fft source files, I wrote this make file to build all the dependencies. However I still get
undefined reference to kiss_fft
undefined reference to kiss_fft_alloc
Which are internal functions of the kiss_fft libs.
Any help would be appreciated. Thanks

Your makefile targets never actually compile kiss_fft.c
e.g.
kiss_fft.o: kiss_fft.c _kiss_fft_guts.h
gcc $(ARGS) -c kiss_fftr.c -o kiss_fft
compiles kiss_fftr.c not kiss_fft.c

I think symbol/function kiss_fft, kiss_fft_alloc are not part of any libary included.
Few things must be checked before you link:
Check if symbols are available in library sndfile
nm | grep "kiss_fft"
Check if you have mentioned the PATH for library in make file.
Include your library path as
-L
Check if prototypes of these functions are in harder files
Include them with
-I
If any C,C++ combination code is used
Use extern "C" sytax.
prototypes of functions must match with prototypes included in library.

Worked it out, thanks for the input. I simply just compiled with:
gcc $# -g -lsndfile -lm -std=gnu99 spec_sub_kiss.c kiss_fft.c kiss_fftr.c -o spec_sub_kiss
Where the -lsndfile is the libraries to read and write some .wav files for my project.