rild快速反转单向list链表的算法

来自android的hardware/ril/reference-ril/atchannel.c

/** add an intermediate response to sp_response*/
static void addIntermediate(const char *line)
{
    ATLine *p_new;

    p_new = (ATLine  *) malloc(sizeof(ATLine));

    p_new->line = strdup(line);

    /* note: this adds to the head of the list, so the list
       will be in reverse order of lines received. the order is flipped
       again before passing on to the command issuer */
    p_new->p_next = sp_response->p_intermediates;
    sp_response->p_intermediates = p_new;
}

/**
 * The line reader places the intermediate responses in reverse order
 * here we flip them back
 */
static void reverseIntermediates(ATResponse *p_response)
{
    ATLine *pcur,*pnext;

    pcur = p_response->p_intermediates;
    p_response->p_intermediates = NULL;

    while (pcur != NULL) {
        pnext = pcur->p_next;
        pcur->p_next = p_response->p_intermediates;
        p_response->p_intermediates = pcur;
        pcur = pnext;
    }
}