代码实现简单数据转义

通常遇到，0xFE 0xFF 则转换为0xFE + 0x00 和 0xFE + 0x01。

Talk is cheap, show me the code.

#include <stdio.h>
#include <assert.h>
#include <string.h>

typedef unsigned char uint8_t;

/*set escape char*/
static void escape_character_process(uint8_t *from, int flen, uint8_t *to, int *olen)
{
    
    int i;
    int s;  
    uint8_t escape_ff[2] = {0xFE,0x01};
    uint8_t escape_fe[2] = {0xFE,0x00};
    for(i = 0; i < olen; i++){
    for(i = 0; i < olen; i++){
    
    /*assert*/
    assert(from);
    
    for (i = 0, s = 0; i < flen; i++, s++){
        if (from[i] == 0xFF){     
            memcpy(to+s,escape_ff,2);
            s += 1;
        }     
        else if (from[i] == 0xFE){   
            memcpy(to+s,escape_fe,2);
            s += 1;
        }   
        else  
            to[s] = from[i];
    }
    
    *olen = s; /*total length*/

}
int main(void)
{
    uint8_t from[4] = {0x01,0xFE,0xFF,0x02};
    uint8_t to[8] = {};
    int i;
    int olen = 0;

    escape_character_process(from, 4, to, &olen);

    for(i = 0; i < olen; i++)
        if (i == olen -1)
            printf("%02x\n",to[i]);
        else
            printf("%02x ",to[i]);

    return 0;
}

原本数据：

0x01,0xFE,0xFF,0x02

0x01,0xFE,0xFF,0x02

 

运行结果：

01 fe 00 fe 01 02