python3嵌入式Linux部署

由于工作需要，要部署python3到rv1126b平台上，该平台上只支持buildroot，没有包管理器，不能直接下载python3。所以拉下源码，进行交叉编译部署，目前已经成功，分享给各位网友。

1、下载源码

PYVER=3.10.12
wget https://www.python.org/ftp/python/$PYVER/Python-$PYVER.tgz
tar xf Python-$PYVER.tgz

2、编译x86架构python3

进入源码根目录，执行：

mkdir build_x86 && cd  build_x86
../configure --prefix=$(pwd)/output
make -j8
make install

3、交叉编译python3

3.1 _tkinter模块不编译

根目录下setup.py注释：

        # if not self.detect_tkinter():
        self.missing.append('_tkinter')

3.2 libffi库缺失

/home/yang/project/jes-ipc/rv1126b-source/Python-3.10.12/Modules/_ctypes/_ctypes.c:107:10: fatal error: ffi.h: No such file or directory
  107 | #include <ffi.h>
      |          ^~~~~~~
compilation terminated.

需要交叉编译libffi库

wget https://github.com/libffi/libffi/releases/download/v3.4.4/libffi-3.4.4.tar.gz

export CROSS_COMPILE=aarch64-rockchip1240-linux-gnu-
export CC=${CROSS_COMPILE}gcc
export AR=${CROSS_COMPILE}ar
export RANLIB=${CROSS_COMPILE}ranlib
export LD=${CROSS_COMPILE}ld
export STRIP=${CROSS_COMPILE}strip

../configure --host=aarch64-rockchip1240-linux-gnu \
            --prefix=/home/yang/project/jes-ipc/rv1126b-source/libffi-3.4.4/build-rv1126b/output \
            --disable-docs

make -j8
make install

3.3 开始交叉编译

mkdir build_rv1126b && cd build_rv1126b
touch set.sh
touch clean.sh
chmod +x *.sh

set.sh脚本内容如下：

#!/bin/bash
set -e

CROSS_PREFIX=aarch64-rockchip1240-linux-gnu-
HOSTPY=/home/yangyang/projects/Python-3.10.12/build-x86/output/bin/python3 # 上一步编译得到的 hostpython
PY_PREFIX=/home/yangyang/projects/Python-3.10.12/build-rv1126b/rv1126b-python3  
PYVER=3.10.12

export CXX=${CROSS_PREFIX}g++
export AR=${CROSS_PREFIX}ar
export RANLIB=${CROSS_PREFIX}ranlib
export LD=${CROSS_PREFIX}ld
export STRIP=${CROSS_PREFIX}strip
export READELF=${CROSS_PREFIX}readelf
export PATH=/home/yangyang/projects/Python-3.10.12/build-x86/output/bin:$PATH
export SYSROOT=/home/yangyang/projects/rv1126b/sysroot
export PKG_CONFIG_SYSROOT_DIR=$SYSROOT
export PKG_CONFIG_LIBDIR=$SYSROOT/usr/lib/pkgconfig:$SYSROOT/lib/pkgconfig
export PKG_CONFIG_PATH=$SYSROOT/usr/lib/pkgconfig:$SYSROOT/lib/pkgconfig
export CPPFLAGS="-I${SYSROOT}/usr/include -I${SYSROOT}/include"
export LDFLAGS="-L${SYSROOT}/usr/lib -L${SYSROOT}/lib"


../configure \
  --host=aarch64-rockchip1240-linux-gnu \
  --build=$(../config.guess) \
  --prefix=${PY_PREFIX} \
  --enable-shared \
  --with-system-ffi \
  --with-ensurepip=install \
  --disable-ipv6 \
  --disable-toolbox-glue \
  ac_cv_file__dev_ptmx=yes ac_cv_file__dev_ptc=no

# 编译
make -j8 HOSTPYTHON=${HOSTPY} BUILDPYTHON=${HOSTPY}

# 安装
make install

clean.sh脚本内容如下：

#!/bin/bash
set -e

# 获取脚本所在目录的绝对路径
SCRIPT_DIR=$(cd "$(dirname "$0")" && pwd)

echo "清理目录: $SCRIPT_DIR"

# 遍历目录下的文件和文件夹
for f in "$SCRIPT_DIR"/*; do
    # 如果是 .sh 文件则跳过
    if [[ "$f" == *.sh ]]; then
        echo "保留: $f"
        continue
    fi

    # 删除其他文件或文件夹
    echo "删除: $f"
    rm -rf "$f"
done

echo "✅ 清理完成"

在编译完成后，日志会有哪些三方库模块没有参与编译的显示，需要注意的是，zlib和openssl等模块比较重要，最好还是参与编译：

The necessary bits to build these optional modules were not found:
_bz2                  _curses               _curses_panel      
_dbm                  _gdbm                 _sqlite3           
_tkinter              nis                   readline           
To find the necessary bits, look in setup.py in detect_modules() for the module's name.


The following modules found by detect_modules() in setup.py, have been
built by the Makefile instead, as configured by the Setup files:
_abc                  pwd                   time         

三方库参与编译方式：加入到CPPFLAGS以及LDFLAGS当中去。

部署到设备上之后，需要下载pip，可以执行：

curl -fsSL -o ./get-pip.py https://bootstrap.pypa.io/get-pip.py
chmod +x ./get-pip.py
python3 get-pip.py