Building mariadb client with Android NDK - c++

Question

Yet another linux build newb here, struggling to build mariadb-client for Android using the NDK.
I have already succesfully built openssl and libiconv, which are perquisites.
Here is what I am doing:
export ANDROID_NDK_ROOT="/home/dev/android-ndk-r12b"
SR="$ANDROID_NDK_ROOT/platforms/android-16/arch-arm"
BR="$ANDROID_NDK_ROOT/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/bin/arm-linux-androideabi-"
mkdir build && cd build
PKG_CONFIG_PATH=$SR/usr/lib/pkgconfig cmake -DCMAKE_AR="$BR"ar -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER="$BR"gcc -DCMAKE_C_FLAGS=--sysroot=$SR -DCMAKE_INSTALL_PREFIX=$SR/usr -DCMAKE_LINKER="$BR"ld -DCMAKE_NM="$BR"nm -DCMAKE_OBJCOPY="$BR"objcopy -DCMAKE_OBJDUMP="$BR"objdump -DCMAKE_RANLIB="$BR"ranlib -DCMAKE_STRIP="$BR"strip -DWITH_EXTERNAL_ZLIB=ON -DICONV_INCLUDE_DIR=$SR/usr/include -DICONV_LIBRARIES=$SR/usr/lib/libiconv.a -DZLIB_INCLUDE_DIR=$SR/usr/include -DZLIB_LIBRARY=$SR/usr/lib/libz.so ../
make install
To break down that last part so it is more readable:
PKG_CONFIG_PATH=$SR/usr/lib/pkgconfig
cmake
-DCMAKE_AR="$BR"ar
-DCMAKE_BUILD_TYPE=Release
-DCMAKE_C_COMPILER="$BR"gcc
-DCMAKE_C_FLAGS=--sysroot=$SR
-DCMAKE_INSTALL_PREFIX=$SR/usr
-DCMAKE_LINKER="$BR"ld
-DCMAKE_NM="$BR"nm
-DCMAKE_OBJCOPY="$BR"objcopy
-DCMAKE_OBJDUMP="$BR"objdump
-DCMAKE_RANLIB="$BR"ranlib
-DCMAKE_STRIP="$BR"strip
-DWITH_EXTERNAL_ZLIB=ON
-DICONV_INCLUDE_DIR=$SR/usr/include
-DICONV_LIBRARIES=$SR/usr/lib/libiconv.a
-DZLIB_INCLUDE_DIR=$SR/usr/include
-DZLIB_LIBRARY=$SR/usr/lib/libz.so
The first error I got was that program_invocation_short_name was undefined in this bit of code:
#elif defined(_GNU_SOURCE)
const char * appname = program_invocation_short_name;
#elif defined(WIN32)
I couldn't find why this is and how to fix, so I decided to cheat my way through by assigning an empty string to it. Possibly with negative repercussions, but I noticed the source doing the same thing a few lines down so I decided to give it a go nonetheless.
Another build attempt, and now I am getting undefined references for iconv functions:
CMakeFiles/mariadb_obj.dir/ma_charset.c.o:ma_charset.c:function mariadb_convert_string: error: undefined reference to 'iconv_open'
CMakeFiles/mariadb_obj.dir/ma_charset.c.o:ma_charset.c:function mariadb_convert_string: error: undefined reference to 'iconv'
CMakeFiles/mariadb_obj.dir/ma_charset.c.o:ma_charset.c:function mariadb_convert_string: error: undefined reference to 'iconv_close'
CMakeFiles/mariadb_obj.dir/ma_context.c.o:ma_context.c:function my_context_spawn_internal: error: undefined reference to 'setcontext'
CMakeFiles/mariadb_obj.dir/ma_context.c.o:ma_context.c:function my_context_continue: error: undefined reference to 'swapcontext'
The libraries are definitely there, as defined in the configuration above. Maybe that's a side effect of the above cheat?
Or maybe something else entirely is going wrong?
Once again, a complete newb in this regard, but I get a newb hunch that it may have something to do with cmake. Is it possibly using the host machine cmake but should be using some "android toolchain" cmake instead? I couldn't find much info on that either, but it could explain why it isn't picking the program_invocation_short_name thingie and the libs.
So, any ideas what is going wrong and how to fix it?
The build env should be clear by the first few lines of code but just in case, it's Ubuntu 16.04 x64, using NDK r12b and the GCC 4.9 toolchain. I am using the following versions of the libraries: libiconv 1.15, openssl 1.1.0f and mariadb_connector_c 3.0.3.

Answer 1

Currently MariaDB Connector/C doesn't support Android NDK, this is planned for the upcoming 3.0.3 release.
To build MariaDB Connector/C with Android NDK you need to checkout the 3.0-portable branch of MariaDB Connector/C.
Iconv support currently doesn't work, same is valid for Kerberos/GSSAPI authentication plugin.
For building MariaDB Connector/C with Android NDK you have specify additionally the following CMake parameters:
-DWITH_ICONV=OFF -DWITH_DYNCOL=OFF -DAUTH_GSSAPI_TYPE=OFF
If you don't need SSL/TLS support, you can disable it by specifying
-DWITH_SSL=OFF