一个for循环没有在操作系统C中执行

Question

我在执行for循环时遇到问题,我创建了一个包含已定义值的静态表,然后将我的表作为参数传递给要处理的函数.基本上我的代码如下所示:

#define ID_01 0x0000
#define ID_02 0x0001
#define ID_03 0x0002
#define ID_04 0x0003
#define ID_05 0x0004
#define ID_06 0x0005
#define ID_07 0x0006
#define ID_08 0x0007
#define ID_09 0x0008
/*...
*/
#define ID_LAST 0xFFFF
static char table[]={
ID_01, ID_02 ,ID_03, ID_04, .... , ID_LAST}

void process( char *table){

    int LastId=0; 
    char *Command; 

    for ( Command=table; LastId==0 ; Command++){
        switch(Command) 
        {
            case ID_01: 
                do_stuff01();
                break;
            case ID_02: 
                do_stuff02();
                break; 
            ...

            case ID_LAST: 
                LastId=1;
                break;
            default: 
                 break;
          } 
    }
}

我试图打印一些消息进行调试,但程序不执行任何打印,即使是在循环之前和之后的那些.

但是当我把for循环改为:

for(i=0;i<10;i++)

所有的信息都打印出来了.但我必须以与我一开始相同的方式处理.

PS:这部分代码是在运行到微控制器的操作系统任务中执行的,我只是一个初学者.

Answer 1

现在,您正在使用switch (Command),其中Command持有地址OD table变量.

更改switch到

switch (*Command) { //Use value at pointed Command.

}

请注意,在进行*Command取消引用时char,这是1byte.您的ID有2个字节,因此您丢失了数据.

更改:

static char table[] = {ID_01, ID_02 ,ID_03, ID_04, .... , ID_LAST}

短路以获得16位值

static unsigned short table[]={ID_01, ID_02 ,ID_03, ID_04, .... , ID_LAST}

稍后,修改您的process功能以接受unsigned short

void process( const unsigned short *table) { //Unsigned short
    int LastId = 0; 
    unsigned short *Command;  //Unsigned short

    for ( Command=table; LastId==0 ; Command++){
        switch(*Command) { //Added star
            //...
        }
    }
    //...

我会将您的process代码重写为:

void process(const unsigned short *table, size_t tableLen) {
    while (tableLen--) {
        switch (*table) {
            case ID_1: /* Do stuff */ break;
        }
        table++; //Increase pointer to next ID element
    }
}

//Usage then like this:
static unsigned short table[] = {ID_1, ID_2, ID_3, ..., ID_n};
//Put pointer and length of table
process(table, sizeof(table)/sizeof(table[0]));