reverse a string separated by ';'

reverse.c

#include <stdlib.h>
#include <stdio.h>

/**
 * @file reverse.c
 * @brief 反转按照‘;’分割的字符串
 * @author zhpeng.is@gmail.com
 * @version 0.0.1
 * @date 2012-04-24
 */
static char *reverse_inner(char *str, char *start, char *stop);

static char *reverse(char *str)
{
    char *p = str;
    while (p != NULL && *p != '\0') {
        char *sep = p;
        while (*sep != '\0' && *sep != ';') {
            sep++;
        }
        reverse_inner(str, p, sep - 1);
        if (*sep == '\0')
            break;
        sep++;
        p = sep;
    }
    return str;
}

char *reverse_inner(char *str, char *start, char *stop)
{
    while (start <= stop) {
        char t = *start;
        *start = *stop;
        *stop = t;

        start++;
        stop--;
    }
    return str;
}

int main()
{
    char line[1024];
    while (scanf("%s", line) != EOF && line[0] != '\0') {
        printf("%s\n", reverse(line));
    }
    return 0;
}