/*
* unix_history_back
*
* Copy last available string to str, if possible. Return 1 if successful.
* Only lines of at most maxlen characters will be considered. In addition
* the first searchlen characters of the history entry must match those of str.
*/
static int unix_history_back(zchar *str, int searchlen, int maxlen)
{
char **prev = history_view;
do {
RING_DEC( history_view, history_buffer, history_end);
if ((history_view == history_next)
|| (*history_view == NULL)) {
os_beep(BEEP_HIGH);
history_view = prev;
return 0;
}
} while (strlen( *history_view) > maxlen
|| (searchlen != 0 && strncmp( (char *)str, *history_view, searchlen)));
strcpy((char *)str + searchlen, *history_view + searchlen);
return 1;
}
/**
* \brief Send a frame splitted into buffers. If the frame size is larger than transfer buffer size
* error returned. If frame transfer status is monitored, specify callback for each frame.
* \param gmacd Pointer to GMAC Driver instance.
* \param sgl Pointer to a scatter-gather list describing the buffers of the ethernet frame.
* \param fTxCb Pointer to callback function.
*/
uint8_t gmacd_send_sg(struct _gmacd* gmacd, uint8_t queue,
const struct _gmac_sg_list* sgl, gmacd_callback_t callback)
{
Gmac* gmac = gmacd->gmac;
struct _gmacd_queue* q = &gmacd->queues[queue];
struct _gmac_desc* desc;
uint16_t idx, tx_head;
int i;
if (callback && !q->tx_callbacks) {
trace_error("Cannot set send callback, no tx_callbacks "\
"buffer configured for queue %u", queue);
}
/* Check parameter */
if (!sgl->size) {
trace_error("gmacd_send_sg: ethernet frame is empty.\r\n");
return GMACD_PARAM;
}
if (sgl->size >= q->tx_size) {
trace_error("gmacd_send_sg: ethernet frame has too many buffers.\r\n");
return GMACD_PARAM;
}
/* Check available space */
if (RING_SPACE(q->tx_head, q->tx_tail, q->tx_size) < sgl->size) {
trace_error("gmacd_send_sg: not enough free buffers in TX queue.\r\n");
return GMACD_TX_BUSY;
}
/* Tag end of TX queue */
tx_head = fixed_mod(q->tx_head + sgl->size, q->tx_size);
idx = tx_head;
if (q->tx_callbacks)
q->tx_callbacks[idx] = NULL;
desc = &q->tx_desc[idx];
desc->status |= GMAC_TX_STATUS_USED;
/* Update buffer descriptors in reverse order to avoid a race
* condition with hardware.
*/
for (i = sgl->size - 1; i >= 0; i--) {
const struct _gmac_sg *sg = &sgl->entries[i];
uint32_t status;
if (sg->size > GMAC_TX_UNITSIZE) {
trace_error("gmacd_send_sg: buffer size is too big.\r\n");
return GMACD_PARAM;
}
RING_DEC(idx, q->tx_size);
/* Reset TX callback */
if (q->tx_callbacks)
q->tx_callbacks[idx] = NULL;
desc = &q->tx_desc[idx];
/* Copy data into transmittion buffer */
if (sg->buffer && sg->size) {
memcpy((void*)desc->addr, sg->buffer, sg->size);
l2cc_clean_region(desc->addr, desc->addr + sg->size);
}
/* Compute buffer descriptor status word */
status = sg->size & GMAC_RX_STATUS_LENGTH_MASK;
if (i == (sgl->size - 1)) {
status |= GMAC_TX_STATUS_LASTBUF;
if (q->tx_callbacks)
q->tx_callbacks[idx] = callback;
}
if (idx == (q->tx_size - 1)) {
status |= GMAC_TX_STATUS_WRAP;
}
/* Update buffer descriptor status word: clear USED bit */
desc->status = status;
DSB();
}
/* Update TX ring buffer pointers */
q->tx_head = tx_head;
/* Now start to transmit if it is not already done */
gmac_start_transmission(gmac);
return GMACD_OK;
}