BeFoR64

Base64 encoding/decoding library for Fortran

A KISS pure Fortran 2003+ library for encoding and decoding any intrinsic type — integers, reals, characters, and unlimited polymorphic variables — to and from Base64 strings.

| 🔢 All intrinsic types<br>Integers I1P–I8P, reals R4P/R8P/opt. R16P, characters, unlimited polymorphic | 📐 Scalars & arrays<br>Scalar and rank-1 array support for all types | 🔗 Pack mixed data<br>Heterogeneous arrays via pack_data | 🔄 Bidirectional<br>Symmetric encode and decode | |:---:|:---:|:---:|:---:| | 🎯 KISS API<br>b64_init, b64_encode, b64_decode — that's it | ⚡ Pure Fortran 2003+<br>No C, no external deps; tested with gfortran & ifort | 🔧 Two build systems<br>fpm and FoBiS.py — static, shared, and test modes | 🔓 Open & documented<br>GPL v3 · BSD · MIT; full API reference & usage guide |

For full documentations (guide, tutorial, examples, etc...) see the BeFoR64 website.

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Authors

• Stefano Zaghi — @szaghi

Contributions are welcome — see the Contributing page.

Copyrights

This project is distributed under a multi-licensing system:

• FOSS projects: GPL v3
• Closed source / commercial: BSD 2-Clause, BSD 3-Clause, or MIT

Anyone interested in using, developing, or contributing to this project is welcome — pick the license that best fits your needs.

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A taste of BeFoR64

use befor64

call b64_init()

character(len=:), allocatable :: code
call b64_encode(n=1.0_R8P, code=code)        ! encode a scalar real
call b64_encode(n=[1_I4P, 2_I4P], code=code) ! or an integer array

real(R8P) :: val
call b64_decode(code='AAAAAAAA8D8=', n=val)  ! decode back

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Usage

BeFoR64 exposes four public procedures and one flag:

| Symbol | Description | |--------|-------------| | b64_init | Initialise the library — call once before any encode/decode | | is_b64_initialized | Logical flag, true after b64_init | | b64_encode / b64_encode_up | Encode intrinsic or unlimited polymorphic variable to Base64 | | b64_decode / b64_decode_up | Decode a Base64 string back to an intrinsic or polymorphic variable | | pack_data | Pack two numeric arrays of different kinds into a byte stream for mixed-type encoding |

Encoded strings are returned as character(len=:), allocatable — a Fortran 2003 feature required by the compiler.

! heterogeneous data: pack first, then encode
real(R8P)               :: a(12)
real(R4P)               :: b(7)
integer(I1P), allocatable :: packed(:)
character(len=:), allocatable :: code

call pack_data(a1=a, a2=b, packed=packed)
call b64_encode(n=packed, code=code)

See the full Usage guide for all supported type combinations.

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Install

FoBiS.py

Standalone — clone, build, and install in one command:

FoBiS.py install szaghi/BeFoR64 -mode static-gnu
FoBiS.py install szaghi/BeFoR64 -mode static-gnu --prefix /path/to/prefix

As a project dependency — declare BeFoR64 in your fobos and run fetch:

[dependencies]
deps_dir = src/third_party
PENF     = https://github.com/szaghi/BeFoR64

FoBiS.py fetch           # fetch and build
FoBiS.py fetch --update  # re-fetch and rebuild

fpm

Add to your fpm.toml:

[dependencies]
BeFoR64 = { git = "https://github.com/szaghi/BeFoR64" }

CMake

cmake -B build && cmake --build build

Makefile

make              # static library
make TESTS=yes    # build and run tests