将函数指针分配给变量

Question

I have 2 files file1.c file2.c. I need to store the Function Pointers passed from file1.c to file2.c in a struct array of size 2.

file1.c

main ()
{
   setFuncPointer ( 1, &call_to_routine_1 );
   setFuncPointer ( 2, &call_to_routine_2 );

void call_to_routine_1 ()
{
  // Do something
}
void call_to_routine_2()
{
  // Do something
}
}

file2.c

struct store_func
{
  UINT32 Id;
  void *fn_ptr;
} func[2];

void setFuncPointer( UINT32 id, void(*cal_fun)())
{
   func[0].id = id;
   /* How to assign the cal_fun to the local fn_ptr and use that later in the code */
}

Also, I am unsure of declaring the void pointer inside the struct. Please suggest the right way of defining and using the callback functions defined in file1.c from file2.c

Thanks in advance

Answer 1

Inside of your struct, this:

void *fn_ptr;

Should be defined as this:

void (*fn_ptr)(void);

And setFuncPointer should be defined as:

void setFuncPointer( UINT32 id, void(*cal_fun)(void))

Then in setFuncPointer , you can do this:

func[0].fn_ptr = cal_fun;

Later on, you can call the function like this:

func[0].fn_ptr();

Also, it's sufficient to call setFuncPointer like this:

setFuncPointer ( 1, call_to_routine_1 );
setFuncPointer ( 2, call_to_routine_2 );