有没有办法将多个值作为C中单个定义的宏值传递给宏函数？

Question

我想在全局标头中将引脚定义声明为一条简单的行，例如：

#define STATUS_LED B,7

然后，我想将此引脚定义传递给以上功能：

CMBset_out(STATUS_LED);

我不知道该如何处理-MY_PIN格式正确，可以在预编译阶段替换。

#define CMBsbi(port, pin) (PORT##port) |= (1<<pin)
#define CMBset_out(port,pin) (DDR##port) |= (1<<pin)
// define pins 
#define STATUS_LED B,7

Then, I want to pass this pin definition to function above (hw_init_states() is declared in the same header file called from main C file):

// runtime initialization
void hw_init_states(){
#ifdef STATUS_LED
    CMBset_out(STATUS_LED);
#endif
}

But I get a compilation error:

Error   1   macro "CMBset_out" requires 2 arguments, but only 1 given   GENET_HW_DEF.h  68  23  Compass IO_proto

Answer 1

It is possible, but you need another level of macros to expand the argument:

#define CMBset_out_X(port,pin) (DDR##port) |= (1<<pin)
#define CMBset_out(x) CMBset_out_X(x)

Of course this means that you can't use the CMBset_out macro with two explicit arguments.

Answer 2

对先前答案的改进，它还允许您使用两个显式参数调用宏。

它应可与任何c99（或更高版本）的编译器一起使用：

#define CMBset_out_X(port,pin) (DDR##port) |= (1<<pin)
#define CMBset_out(...) CMBset_out_X(__VA_ARGS__)

#define STATUS_LED B,7
CMBset_out(STATUS_LED)
CMBset_out(B, 7)