Function cirbuf_get_buf_head

dpdk/lib/cmdline/cmdline_cirbuf.c:323–357

/* convert to buffer */

int
cirbuf_get_buf_head(struct cirbuf *cbuf, char *c, unsigned int size)
{
	unsigned int n;

	if (!cbuf || !c)
		return -EINVAL;

	n = (size < CIRBUF_GET_LEN(cbuf)) ? size : CIRBUF_GET_LEN(cbuf);

	if (!n)
		return 0;

	if (cbuf->start <= cbuf->end) {
		dprintf("s[%d] -> d[%d] (%d)\n", cbuf->start, 0, n);
		memcpy(c, cbuf->buf + cbuf->start , n);
	}
	else {
		/* check if we need to go from end to the beginning */
		if (n <= cbuf->maxlen - cbuf->start) {
			dprintf("s[%d] -> d[%d] (%d)\n", 0, cbuf->start, n);
			memcpy(c, cbuf->buf + cbuf->start , n);
		}
		else {
			dprintf("s[%d] -> d[%d] (%d)\n", cbuf->start, 0,
				cbuf->maxlen - cbuf->start);
			dprintf("s[%d] -> d[%d] (%d)\n", 0, cbuf->maxlen - cbuf->start,
				n - cbuf->maxlen + cbuf->start);
			memcpy(c, cbuf->buf + cbuf->start , cbuf->maxlen - cbuf->start);
			memcpy(c + cbuf->maxlen - cbuf->start, cbuf->buf,
				   n - cbuf->maxlen + cbuf->start);
		}
	}
	return n;
}

/* convert to buffer */