python - C/Python绑定：指针地址修改

Question

资源

C++

extern "C"
{
    Service* create_service( int port )
    {
        Settings settings;
        settings.set_port( port );

        auto service = new Service( settings );

        std::cout << "create_service returning pointer address: " << service << std::endl;

        return service;
    }

    void release_service( Service* service )
    {
        std::cout << "release_service consuming pointer address: " << service << std::endl;
        delete service;
    }
}

Python

from ctypes import *

library = cdll.LoadLibrary('distribution/library/libhelpers.dylib')

class Service(object):
    def __init__(self, port):
        self.obj = library.create_service(port)
        print "__init__ address: ", self.obj

    def __del__(self):
        print "__del__", self.obj
        library.release_service(self.obj);

安慰

create_service 返回指针地址：0x7fc3a0e330e0

初始化地址：-1595723552

删除地址：-1595723552

release_service消费指针地址：0xffffffffa0e330e0

分段错误：11

错误

异常类型：EXC_BAD_ACCESS (SIGSEGV)

异常代码：0xffffffff914d37a0 处的 KERN_INVALID_ADDRESS

构建（cmake）

设置（CMAKE_CXX_COMPILER clang++）

设置（CMAKE_CXX_FLAGS“-stdlib=libc++ -std=c++11 -Wall -Wextra -Weffc++ -pedantic”）

add_library( 助手共享 ${MANIFEST} )

target_link_libraries（助手休息床）

描述

当将 C++ 类实例作为指针返回时。Python 收到正确的地址。但是，在以后使用此地址时，它似乎已被修改。

Answer 1

看来我没有给 ctypes 提供足够的上下文。

from ctypes import *

library = cdll.LoadLibrary('distribution/library/libhelpers.dylib')

class Service(object):
    def __init__(self, port):
        library.create_service.restype = c_void_p
        self.obj = library.create_service(port)

    def __del__(self):
        library.release_service.argtypes = [c_void_p]
        library.release_service(self.obj);