fortran-zlib

March 17, 2025 · View on GitHub

A collection of Fortran 2018 interface bindings to selected zlib functions. The library is also available on MacPorts.

Build Instructions

Build and install the library with the provided Makefile:

$ make
$ make install PREFIX=/opt

Link your program against /opt/lib/libfortran-zlib.a -lz. Optionally, overwrite the default compiler:

$ make FC=ifx

Or, use the Fortran Package Manager:

$ fpm build --profile release

Build and run the test program:

$ make test
$ ./test_zlib

Example

The following basic example compresses and uncompresses an input string.

! example.f90
program main
    use :: zlib
    implicit none (type, external)

    character(len=:), allocatable :: str_in, str_out, str_x
    integer(kind=z_ulong)         :: len_in, len_out, len_x
    integer                       :: rc

    ! Input.
    str_in = repeat('Fortran ', 10)
    len_in = len(str_in, kind=z_ulong)

    ! Compress.
    len_x = compress_bound(len_in)
    allocate (character(len=len_x) :: str_x)
    rc = compress(str_x, len_x, str_in, len_in)
    if (rc /= Z_OK) stop 'Error: compress() failed'

    ! Uncompress.
    len_out = len_in
    allocate (character(len=len_out) :: str_out)
    rc = uncompress(str_out, len_out, str_x, len_x)
    if (rc /= Z_OK) stop 'Error: uncompress() failed'
end program main

If the library has been installed to /opt, then compile, link, and run the example program with:

$ gfortran -I/opt/include/libfortran-zlib -o example example.f90 /opt/lib/libfortran-zlib.a -lz
$ ./example

Coverage

C function	Fortran interface
`adler32`	`adler32`
`adler32_z`	`adler32_z`
`compress`	`compress`
`compress2`	`compress2`
`compressBound`	`compress_bound`
`crc32`	`crc32`
`crc32_z`	`crc32_z`
`deflate`	`deflate`
`deflateEnd`	`deflate_end`
`deflateInit`	`deflate_init`
`deflateInit2`	`deflate_init2`
`inflate`	`inflate`
`inflateEnd`	`inflate_end`
`inflateInit`	`inflate_init`
`inflateInit2`	`inflate_init2`
`uncompress`	`uncompress`
`uncompress2`	`uncompress2`

Fortran Package Manager

You can add fortran-zlib as an fpm dependency:

[dependencies]
fortran-zlib = { git = "https://github.com/interkosmos/fortran-zlib.git" }

Licence

ISC