如何创建 PHP 扩展以与 C 函数交互

mkdir my_extension
cd my_extension

vim my_extension.c

#include <php.h>

PHP_FUNCTION(my_c_function) {
  // ... 调用 C 函数 ...
}

PHP_MINIT_FUNCTION(my_extension) {
  // 初始化扩展
  zend_register_internal_function("my_c_function", my_c_function, 0);
  return SUCCESS;
}

PHP_FUNCTION(my_extension_info) {
  php_info_print_table_start();
  php_info_print_table_row(2, "My Extension", "enabled");
  php_info_print_table_end();
}

PHP_MINIT_FUNCTION(my_extension) {
  // ...
  zend_declare_function(NULL, "my_extension_info", my_extension_info, 0, 0, 0, 0);
  // ...
}

cd ..
phpize
./configure
make
make install

<?php
phpinfo();

php test.php

#include <php.h>

int factorial(int n) {
  if (n == 0) {
    return 1;
  }
  return n * factorial(n - 1);
}

PHP_FUNCTION(factorial) {
  int n;

  if (zend_parse_parameters(ZEND_NUM_ARGS(), "l", &n) == FAILURE) {
    RETURN_NULL();
  }

  RETURN_LONG(factorial(n));
}

phpize
./configure
make
make install

<?php
echo factorial(5); // 输出： 120