c plugin插件 简单例子

file:

maic.c

plugin_a.c

Makefile

main.c:

#include <stdio.h>
#include <dlfcn.h>

#define PLUGIN_NAME "./plugin.so"
#define FUNC_NAME "func"

int main()
{
    int ret = 0;
    void *flib = NULL;
    char *err_info = NULL;
    int (*pfunc)(int a, int b);

    printf("this plugin test!\n");

    flib = dlopen(PLUGIN_NAME, RTLD_LAZY);
    err_info = dlerror();

    if(err_info != NULL)
    {
        printf("dlopen er, err:[%s]\n", err_info);
        return 1;
    }

    *(void **)(&pfunc) = dlsym(flib, FUNC_NAME);
    err_info = dlerror();

    if(err_info != NULL)
    {
        printf("dlsym er, err:[%s]\n", err_info);
        return 1;
    }

    ret = pfunc(1, 2);
    printf("result:[%d]\n", ret);

    dlclose(flib);
    err_info = dlerror();

    if(err_info != NULL)
    {
        printf("dlclose er, err:[%s]\n", err_info);
        return 1;
    }

    return 0;
}

plugin_a.c:

int func(int a, int b)
{
    return a + b;
}

Makefile:

EXEC=test 

all: plugin.so
	gcc -o $(EXEC) main.c -ldl

plugin.so: plugin.o
	gcc -shared -lc -o plugin.so plugin.o

plugin.o:
	gcc -c -fpic plugin_a.c -o plugin.o

clean:
	-rm -f $(EXEC) *.elf *.gdb *.o *.so