Contiki 宏定义

• PROCESS

PROCESS宏定义在core\sys的process.h文件内，如下：

#define PROCESS(name, strname) \
  PROCESS_THREAD(name, ev, data); \
  struct process name = { NULL, strname, \
                          process_thread_##name }
#define PROCESS_THREAD(name, ev, data) \
static PT_THREAD(process_thread_##name(struct pt *process_pt, \
                       process_event_t ev, \
                       process_data_t data))
#define PT_THREAD(name_args) char name_args

• AUTOSTART_PROCESSES

#define AUTOSTART_PROCESSES(...) \
struct process * const autostart_processes[] = {__VA_ARGS__, NULL}

• ROCESS_BEGIN

#define PROCESS_BEGIN() PT_BEGIN(process_pt)
#define PT_BEGIN(pt) { char PT_YIELD_FLAG = 1; LC_RESUME((pt)->lc)
#define LC_RESUME(s) switch(s) { case 0:

把参数替换，结果如下：

{
    char PT_YIELD_FLAG = 1; /*将PT_YIELD_FLAG置1，类似于关中断？？？*/
    switch(process_pt->lc) /*程序根据lc的值进行跳转，lc用于保存程序断点*/
    {
        case 0: /*第一次执行从这里开始，可以放一些初始化的东东*/
            ;

• PROCESS_END

#define PROCESS_END() PT_END(process_pt)
#define PT_END(pt) LC_END((pt)->lc); PT_YIELD_FLAG = 0; \ PT_INIT(pt); return PT_ENDED; }
#define LC_END(s) }
#define PT_INIT(pt) LC_INIT((pt)->lc)
#define LC_INIT(s) s = 0;
#define PT_ENDED 3

把参数替换，结果如下：
    }
    PT_YIELD_FLAG = 0;
    (process_pt)->lc = 0;

    return 3;
}

• PROCESS_YIELD

/*即进程主动让出执行权*/
#define PROCESS_YIELD() PT_YIELD(process_pt)
#define LC_SET(s) s = __LINE__; case __LINE__: /*保存被中断的行数*/

/*继续展开如下，Yield from the current protothread*/
#define PT_YIELD(pt) \
do { \
PT_YIELD_FLAG = 0; \
LC_SET((pt)->lc); \
if(PT_YIELD_FLAG == 0) { \
return PT_YIELDED; \
} \
} while(0)

// 把参数替换，结果如下：

do {
    PT_YIELD_FLAG = 0;
    (process_pt)->lc = __LINE__;
    case __LINE__:
    if(PT_YIELD_FLAG == 0) {
        return PT_YIELDED;
    }

} while(0)