/**
* @brief Sends TFTP ACK packet
* @param upcb: pointer on udp_pcb structure
* @param to: pointer on the receive IP address structure
* @param to_port: receive port number
* @param block: block number
* @retval: err_t: error code
*/
static err_t IAP_tftp_send_ack_packet(struct udp_pcb *upcb, struct ip_addr *to, int to_port, int block)
{
err_t err;
struct pbuf *pkt_buf; /* Chain of pbuf's to be sent */
/* create the maximum possible size packet that a TFTP ACK packet can be */
char packet[TFTP_ACK_PKT_LEN];
/* define the first two bytes of the packet */
IAP_tftp_set_opcode(packet, TFTP_ACK);
/* Specify the block number being ACK'd.
* If we are ACK'ing a DATA pkt then the block number echoes that of the DATA pkt being ACK'd (duh)
* If we are ACK'ing a WRQ pkt then the block number is always 0
* RRQ packets are never sent ACK pkts by the server, instead the server sends DATA pkts to the
* host which are, obviously, used as the "acknowledgement". This saves from having to sEndTransferboth
* an ACK packet and a DATA packet for RRQs - see RFC1350 for more info. */
IAP_tftp_set_block(packet, block);
/* PBUF_TRANSPORT - specifies the transport layer */
pkt_buf = pbuf_alloc(PBUF_TRANSPORT, TFTP_ACK_PKT_LEN, PBUF_POOL);
if (!pkt_buf) /*if the packet pbuf == NULL exit and EndTransfertransmission */
{
udp_lcd_y += UPDATE_WORD_SIZE + UPDATE_ROW_DISTANCE;
lcd_font24(udp_lcd_x,udp_lcd_y,COLOR_POINT,COLOR_BACK,"> ÒÔÌ«ÍøÉý¼¶³ö´íÁË¡£´íÎó´úÂ룺1",UPDATE_FONT);
UDP_AddUpdateError();
// #ifdef USE_LCD
// LCD_SetTextColor(Red);
// LCD_DisplayStringLine(Line9, (uint8_t*)"Can not allocate pbuf");
// #endif
return ERR_MEM;
}
/* Copy the original data buffer over to the packet buffer's payload */
memcpy(pkt_buf->payload, packet, TFTP_ACK_PKT_LEN);
/* Sending packet by UDP protocol */
err = udp_sendto(upcb, pkt_buf, to, to_port);
/* free the buffer pbuf */
pbuf_free(pkt_buf);
return err;
}
/**
* @brief Sends TFTP ACK packet
* @param upcb: pointer on udp_pcb structure
* @param to: pointer on the receive IP address structure
* @param to_port: receive port number
* @param block: block number
* @retval: err_t: error code
*/
static err_t IAP_tftp_send_ack_packet(struct udp_pcb *upcb, struct ip_addr *to, int to_port, int block)
{
err_t err;
struct pbuf *pkt_buf; /* Chain of pbuf's to be sent */
/* create the maximum possible size packet that a TFTP ACK packet can be */
char packet[TFTP_ACK_PKT_LEN];
memset(packet, 0, TFTP_ACK_PKT_LEN *sizeof(char));
/* define the first two bytes of the packet */
IAP_tftp_set_opcode(packet, TFTP_ACK);
/* Specify the block number being ACK'd.
* If we are ACK'ing a DATA pkt then the block number echoes that of the DATA pkt being ACK'd (duh)
* If we are ACK'ing a WRQ pkt then the block number is always 0
* RRQ packets are never sent ACK pkts by the server, instead the server sends DATA pkts to the
* host which are, obviously, used as the "acknowledgement". This saves from having to sEndTransferboth
* an ACK packet and a DATA packet for RRQs - see RFC1350 for more info. */
IAP_tftp_set_block(packet, block);
/* PBUF_TRANSPORT - specifies the transport layer */
pkt_buf = pbuf_alloc(PBUF_TRANSPORT, TFTP_ACK_PKT_LEN, PBUF_POOL);
if (!pkt_buf) /*if the packet pbuf == NULL exit and EndTransfertransmission */
{
#ifdef USE_LCD
LCD_ErrLog("Can not allocate pbuf\n");
#endif
return ERR_MEM;
}
/* Copy the original data buffer over to the packet buffer's payload */
memcpy(pkt_buf->payload, packet, TFTP_ACK_PKT_LEN);
/* Sending packet by UDP protocol */
err = udp_sendto(upcb, pkt_buf, to, to_port);
/* free the buffer pbuf */
pbuf_free(pkt_buf);
return err;
}
