C中 union 成员的条件替换

Question

我有

typedef union 
{
    void (*fp1p)(void);
    void (*fp2p)(uint32_t);
    void (*fp3p)(uint32_t, uint32_t);
    void (*fp4p)(uint32_t, uint32_t, uint32_t);
    uint32_t (*fp5p)(uint32_t);
    uint32_t (*fp6p)(uint32_t, uint32_t);
    uint32_t (*fp7p)(uint32_t, uint32_t, uint32_t);
} fp;
struct command
{
    char *name;  //command name
    uint32_t minargs;
    uint32_t maxargs;
    int minval;
    int maxval;
    fp read_func_pointer;
    fp write_func_pointer;
};

struct command commands[] = 
{
    [0] = { "reg1001", 0,0,0,0, .read_func_pointer.fp6p = TDC1000_SPIByteReadReg, .write_func_pointer.fp4p = TDC1000_SPIByteWriteReg },
    //
   //
   };

然后

if(condition)
{
   uint32_t ret_val = commands[0].read_func_pointer.fp6p(…);
}
else
{
   commands[0]. write_func_pointer.fp6p(…);
}

我怎样才能使它成为通用的而不是 .fp6p？

Answer 1

我不知道这是否适合您，但是向您的结构添加一个表示函数指针类型的枚举怎么样？

在条件语句中，您可以打开枚举，然后调用正确的函数指针。