通用版的插入排序

isort.c

/* 指针运算很费脑子 TAT */

void swap(char *s1, char *s2, size_t size) {
    int i;
    char tmp;

    for (i = 0; i < size; i++, s1++, s2++) {
        tmp = *s1;
        *s1 = *s2;
        *s2 = tmp;
    }
}

void isort(void *base, size_t nmemb, size_t size,
           int (*compare ) (const void *, const void * )) {
    int i = 1;
    char *array, *initial, *sorted, *tmp; 

    initial = (char *)base;
    array = initial + size;

    for (i = 1; i < nmemb; i++, array += size) {
        for (sorted = initial; sorted < array; sorted += size) {
            if (compare(sorted, array) > 0) {
                for (tmp = array; tmp > sorted; tmp -= size) {
                    swap(tmp, tmp - size, size);
                }
                break;
            }
        }
    }
}