Cffi 1.15.1

Homepage: https://cffi.readthedocs.io
Manpage: https://cffi.readthedocs.io/en/stable/overview.html
Changelog: https://github.com/python-cffi/cffi/releases
Repository: https://github.com/python-cffi/cffi
Package: master/make/pkgs/python-cffi/
Maintainer: -

Add python-cffi, a Foreign Function Interface package for calling C libraries from Python.

Installation notes

Python shall be externalized on Freetz-NG.

After the system build, before using cffi, you also need curl, pip, pycparser (version 2.18).

To install pip on Freetz-NG:

curl https://bootstrap.pypa.io/pip/2.7/get-pip.py --output get-pip.py
python get-pip.py --user

To install the pycparser Python module:

python -m pip install "pycparser<2.19"

Usage notes

The ffibuilder.compile() method of the cffi module will not work because Freetz-NG does not include a compiler. To overcome this issue, in a temporary directory of the build system create a file named mips-linux-uclibc-gcc.c including this code.

int main(int argc, char *argv[]) {
    printf("\n------ Executed command:\n");
    for (int i = 0; i < argc; i++) {
      if (i > 0) printf(" ");
        printf("%s", argv[i]);
    }
    printf("\n");
    printf("------ (end)\n\n");
    return 0;
}

Cross-compile it (on the build system):

/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -I/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/include/python2.7 mips-linux-uclibc-gcc.c -o mips-linux-uclibc-gcc

Move the obtained executable code to Freetz-NG:

mkdir -p /home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/
mv mips-linux-uclibc-gcc /home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc

Then, after running ffibuilder.compile(), you need to move the created files to the build system and execute the commands shown by the above program.

To each, command, you shoud add:

-I/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/include/python2.7

The obtained shared object shall be moved back to Freetz-NG and imported in Python.

Example using API Mode, calling C sources instead of a compiled library:

create pi.c following instructions
create pi.h following instructions
create pi_extension_build.py following instructions
Build the extension following instructions.

Obtained printout:

>>> ffibuilder.compile(verbose=True)
generating ./_pi.c
(already up-to-date)
the current directory is '/var/media/myfreetz'
running build_ext
building '_pi' extension
/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -c _pi.c -o ./_pi.o

------ Executed command:
/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -c _pi.c -o ./_pi.o
------ (end)

/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -c pi.c -o ./pi.o

------ Executed command:
/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -c pi.c -o ./pi.o
------ (end)

/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -shared ./_pi.o ./pi.o -L/usr/lib -lm -lpython2.7 -o ./_pi.so

------ Executed command:
/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -shared ./_pi.o ./pi.o -L/usr/lib -lm -lpython2.7 -o ./_pi.so
------ (end)

'/var/media/myfreetz/_pi.so'

Move pi.c, _pi.c, pi.h to a temporary directory of the build system.

On the build system, run the cross-compiler basing on the above istructions:

/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -I/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/include/python2.7 -c _pi.c -o ./_pi.o

/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -c pi.c -o ./pi.o

/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/bin/mips-linux-uclibc-gcc -fno-strict-aliasing -march=34kc -mtune=34kc -msoft-float -Ofast -pipe -Wa,--trap -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wl,-I/usr/lib/freetz/ld-uClibc.so.1 -DNDEBUG -fno-inline -fPIC -I/usr/include/python2.7 -I/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/include/python2.7 -c _pi.c -o ./_pi.o

Notice the addition of -I/home/$USER/freetz-ng/toolchain/build/mips_gcc-13.3.0_uClibc-1.0.52-nptl_kernel-4.9/mips-linux-uclibc/include/python2.7.

Move _pi.so to Freetz-NG.

The following Python program will run without errors.

from _pi.lib import pi_approx
approx = pi_approx(10)
assert str(approx).startswith("3.")

approx = pi_approx(10000)
assert str(approx).startswith("3.1")

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