如何用ctypes封装Fortran为Python3.12+可分发包（基于meson-python）

针对你遇到的setuptools不支持Fortran编译、pip安装无法触发Meson流程的问题，以下是完整的可落地方案，纯用ctypes实现封装，兼容Python3.12+并可发布至PyPI。

1. 标准化项目结构 #

调整目录结构，让Meson编译的共享库能和Python模块同目录安装：

fortran2python/
├── src/
│   ├── fortran/
│   │   └── mymath.f90       # 你的Fortran代码
│   └── python/
│       └── fortran2python/
│           ├── __init__.py   # 包入口
│           └── _core.py      # ctypes封装逻辑
├── meson.build               # Meson编译配置
├── pyproject.toml            # PEP 518构建配置
└── README.md                 # 项目说明（可选）

2. 配置pyproject.toml #

使用meson-python作为PEP 517构建后端，让pip自动触发Meson编译流程：

[build-system]
requires = ["meson-python>=0.13.0", "meson>=1.2.0"]
build-backend = "mesonpy"

[project]
name = "fortran2python"
version = "0.1.0"
authors = [{"name" = "Your Name", "email" = "your@email.com"}]
description = "Python wrapper for Fortran code using pure ctypes"
readme = "README.md"
requires-python = ">=3.12"
classifiers = [
    "Programming Language :: Python :: 3.12",
    "Programming Language :: Fortran",
    "License :: OSI Approved :: MIT License",
]

3. 编写meson.build编译配置 #

指定Fortran编译规则，将共享库安装到Python包目录下：

# 项目元信息
project('fortran2python', 'fortran', 'python',
        version: '0.1.0',
        default_options: ['buildtype=release'])

# 编译Fortran为共享库
fortran_lib = shared_library(
    'mymath',
    sources: 'src/fortran/mymath.f90',
    install: true,
    install_dir: 'fortran2python'  # 库将和Python模块同目录安装
)

# 安装Python模块文件
python_install_sources = [
    'src/python/fortran2python/__init__.py',
    'src/python/fortran2python/_core.py'
]

install_data(
    python_install_sources,
    install_dir: 'fortran2python'
)

4. 纯ctypes封装Python模块 #

示例Fortran代码（src/fortran/mymath.f90） #

module mymath
    implicit none
contains
    function add(a, b) result(res)
        integer, intent(in) :: a, b
        integer :: res
        res = a + b
    end function add

    function multiply(a, b) result(res)
        real, intent(in) :: a, b
        real :: res
        res = a * b
    end function multiply
end module mymath

ctypes封装逻辑（src/python/fortran2python/_core.py） #

处理跨平台库路径，声明函数签名并暴露给Python：

import ctypes
import os
import sys
from importlib.resources import files

def _load_library():
    # 适配不同平台的共享库后缀
    lib_name = 'mymath'
    if os.name == 'nt':
        lib_ext = '.dll'
    elif sys.platform == 'darwin':
        lib_ext = '.dylib'
    else:
        lib_ext = '.so'
    
    # 获取安装后的库路径
    lib_path = files('fortran2python').joinpath(f'{lib_name}{lib_ext}')
    
    # 加载共享库
    lib = ctypes.CDLL(str(lib_path))
    
    # 声明Fortran函数的参数类型和返回值类型
    lib.add.argtypes = [ctypes.c_int, ctypes.c_int]
    lib.add.restype = ctypes.c_int
    
    lib.multiply.argtypes = [ctypes.c_float, ctypes.c_float]
    lib.multiply.restype = ctypes.c_float
    
    return lib

# 预加载库并暴露函数
_lib = _load_library()
add = _lib.add
multiply = _lib.multiply

包入口文件（src/python/fortran2python/__init__.py） #

from ._core import add, multiply

__version__ = "0.1.0"

5. 测试安装与验证 #

# 创建Python3.12+虚拟环境
python3.12 -m venv venv
source venv/bin/activate  # Windows系统执行：venv\Scripts\activate

# 本地安装（自动触发Meson编译Fortran代码）
pip install .

# 验证功能
python -c "import fortran2python; print(fortran2python.add(2, 3)); print(fortran2python.multiply(2.5, 4.0))"

6. 发布至PyPI #

# 构建分发包
pip build .

# 上传至PyPI（需提前安装twine并注册PyPI账号）
pip install twine
twine upload dist/*

内容的提问来源于stack exchange，提问作者Zaus