Question

我可以使用mingw正确编译DLL并执行导出/导入操作。我正在寻找的是正确定义dll onload功能，就像在MS VC产品中一样。谷歌没有发现任何事情。任何人有任何想法或教程的链接？

Answer 1

好的，所以经过一些摆弄......它正在发挥作用。对于其他任何有问题的人来说，这是。我的问题与编译无关，而不是动态加载。这是几个教程/问题/方法的混搭让我达到了这一点。

dll.c


#include <stdio.h>
#include <windows.h>
#include "dll.h"

//extern "C" BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD Reason, LPVOID LPV) {
//This one was only necessary if you were using a C++ compiler

BOOL WINAPI DllMain(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpvReserved) {

    switch (fdwReason)
    {
        case DLL_PROCESS_ATTACH:
            // Code to run when the DLL is loaded
        printf ("Load working...\n");
            break;

        case DLL_PROCESS_DETACH:
            // Code to run when the DLL is freed
        printf ("Unload working...\n");
            break;

        case DLL_THREAD_ATTACH:
            // Code to run when a thread is created during the DLL's lifetime
        printf ("ThreadLoad working...\n");
            break;

        case DLL_THREAD_DETACH:
            // Code to run when a thread ends normally.
        printf ("ThreadUnload working...\n");
            break;
    }

    return TRUE;
} 

EXPORT void hello(void) {
    printf ("Hello\n");
}

dll.h


#ifndef DLL_H_
#define DLL_H_

#ifdef BUILD_DLL
/* DLL export */
#define EXPORT __declspec(dllexport)
#else
/* EXE import */
#define EXPORT __declspec(dllimport)
#endif

EXPORT void hello(void);

#endif /* DLL_H_ */

的hello.c


#include <windows.h>
#include <stdio.h>

int main () {

    /*Typedef the hello function*/
    typedef void (*pfunc)();

    /*Windows handle*/
    HANDLE hdll;

    /*A pointer to a function*/
    pfunc hello;

    /*LoadLibrary*/
    hdll = LoadLibrary("message.dll");

    /*GetProcAddress*/
    hello = (pfunc)GetProcAddress(hdll, "hello");

    /*Call the function*/
    hello();
    return 0;
}

编译时

gcc -c -DBUILD_DLL dll.c
gcc -shared -o message.dll dll.o -Wl,--out-implib,libmessage.a
gcc -c hello.c
gcc -o hello.exe hello.o message.dll

产生预期的输出

Load working...
Hello
Unload working...

Answer 2

由于mingw只是GCC的Windows端口和相关工具，因此您可以使用GCC constructor and destructor attributes。这些工作分别用于共享库和静态库，并分别在main运行之前和之后执行代码。此外，您可以为每个库指定多个构造函数和析构函数。

static void __attribute__((constructor))
your_lib_init(void)
{
    fprintf(stderr, "library init\n");
}

static void __attribute__((destructor))
your_lib_destroy(void)
{
    fprintf(stderr, "library destroy\n");
}

如何为mingw32指定dll onload函数？

2 个答案: