/************************************************************************
* NAME: fnet_telnet_putchar
*
* DESCRIPTION:
************************************************************************/
static void fnet_telnet_putchar(long id, int character)
{
struct fnet_telnet_session_if *session = (struct fnet_telnet_session_if *)id;
if(session->state != FNET_TELNET_STATE_CLOSING)
{
tx_buffer_write(session, (char)character);
if(tx_buffer_free_space(session) < 1) /* Buffer is full => flush. */
{
fnet_telnet_send(session);
}
}
}
/************************************************************************
* DESCRIPTION:
************************************************************************/
static void fnet_telnet_putchar(fnet_index_t id, fnet_char_t character)
{
struct fnet_telnet_session_if *session = (struct fnet_telnet_session_if *)id;
if(session->state != FNET_TELNET_STATE_CLOSING)
{
tx_buffer_write(session, (fnet_uint8_t)character);
if(tx_buffer_free_space(session) < 1u) /* Buffer is full => flush. */
{
fnet_telnet_send(session);
}
}
}
/************************************************************************
* NAME: fnet_telnet_state_machine
*
* DESCRIPTION: Telnet server state machine.
************************************************************************/
static void fnet_telnet_state_machine( void *telnet_if_p )
{
struct sockaddr foreign_addr;
int res;
struct fnet_telnet_if *telnet = (struct fnet_telnet_if *)telnet_if_p;
char rx_data[1];
int len;
int i;
struct fnet_telnet_session_if *session;
for(i=0; i<FNET_CFG_TELNET_SESSION_MAX; i++)
{
session = &telnet->session[i];
telnet->session_active = session;
do
{
switch(session->state)
{
/*---- LISTENING ------------------------------------------------*/
case FNET_TELNET_STATE_LISTENING:
len = sizeof(foreign_addr);
session->socket_foreign = accept(telnet->socket_listen, (struct sockaddr *) &foreign_addr, &len);
if(session->socket_foreign != SOCKET_INVALID)
{
#if FNET_CFG_DEBUG_TELNET
{
char ip_str[FNET_IP_ADDR_STR_SIZE];
fnet_inet_ntop(foreign_addr.sa_family, foreign_addr.sa_data, ip_str, sizeof(ip_str));
FNET_DEBUG_TELNET("\nTELNET: New connection: %s; Port: %d.", ip_str, fnet_ntohs(foreign_addr.sa_port));
}
#endif
/* Init Shell. */
session->shell_descriptor = fnet_shell_init(&session->shell_params);
if(session->shell_descriptor == FNET_ERR)
{
session->shell_descriptor = 0;
FNET_DEBUG_TELNET("TELNET: Shell Service registration error.");
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
else
{
listen(telnet->socket_listen, --telnet->backlog); /* Ignor other connections.*/
/* Reset TX timeout. */
session->state = FNET_TELNET_STATE_RECEIVING; /* => WAITING data */
}
}
break;
/*---- NORMAL -----------------------------------------------*/
case FNET_TELNET_STATE_RECEIVING:
if(rx_buffer_free_space(session)>0)
{
res = recv(session->socket_foreign, rx_data, 1, 0);
if(res == 1)
{
if(rx_data[0] == FNET_TELNET_CMD_IAC )
{
session->state = FNET_TELNET_STATE_IAC; /*=> Handle IAC */
}
else
{
rx_buffer_write (session, rx_data[0]);
}
}
else if (res == SOCKET_ERROR)
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
}
break;
/*---- IAC -----------------------------------------------*/
case FNET_TELNET_STATE_IAC:
FNET_DEBUG_TELNET("TELNET: STATE_IAC");
if((res = recv(session->socket_foreign, rx_data, 1, 0) )!= SOCKET_ERROR)
{
if(res)
{
switch(rx_data[0])
{
case FNET_TELNET_CMD_WILL:
session->state = FNET_TELNET_STATE_DONT;
break;
case FNET_TELNET_CMD_DO:
session->state = FNET_TELNET_STATE_WONT;
break;
case FNET_TELNET_CMD_WONT:
case FNET_TELNET_CMD_DONT:
session->state = FNET_TELNET_STATE_SKIP ;
break;
case FNET_TELNET_CMD_IAC:
/*
the IAC need be doubled to be sent as data, and
the other 255 codes may be passed transparently.
*/
rx_buffer_write (session, rx_data[0]);
default:
session->state = FNET_TELNET_STATE_RECEIVING; /*=> Ignore commands */
}
}
}
else
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
break;
/*---- DONT & WONT -----------------------------------------------*/
case FNET_TELNET_STATE_DONT:
case FNET_TELNET_STATE_WONT:
{
char command;
if(session->state == FNET_TELNET_STATE_DONT)
{
FNET_DEBUG_TELNET("TELNET: STATE_DONT");
command = FNET_TELNET_CMD_DONT;
}
else
{
FNET_DEBUG_TELNET("TELNET: STATE_WONT");
command = FNET_TELNET_CMD_WONT;
}
if(tx_buffer_free_space(session) >= 3)
{
res = recv(session->socket_foreign, rx_data, 1, 0);
if(res == 1)
{
/* Send command. */
fnet_telnet_send_cmd(session, command, rx_data[0]);
session->state = FNET_TELNET_STATE_RECEIVING;
}
else if (res == SOCKET_ERROR)
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
}
}
break;
/*---- SKIP -----------------------------------------------*/
case FNET_TELNET_STATE_SKIP:
FNET_DEBUG_TELNET("TELNET: STATE_SKIP");
res = recv(session->socket_foreign, rx_data, 1, 0);
if(res == 1)
{
session->state = FNET_TELNET_STATE_RECEIVING;
}
else if (res == SOCKET_ERROR)
{
session->state = FNET_TELNET_STATE_CLOSING; /*=> CLOSING */
}
break;
/*---- CLOSING --------------------------------------------*/
case FNET_TELNET_STATE_CLOSING:
FNET_DEBUG_TELNET("TELNET: STATE_CLOSING");
if(session->shell_descriptor)
{
fnet_shell_release(session->shell_descriptor);
session->shell_descriptor = 0;
}
session->rx_buffer_head = session->rx_buffer;
session->rx_buffer_tail = session->rx_buffer;
closesocket(session->socket_foreign);
session->socket_foreign = SOCKET_INVALID;
listen(telnet->socket_listen, ++telnet->backlog); /* Allow connection.*/
session->state = FNET_TELNET_STATE_LISTENING; /*=> LISTENING */
break;
default:
break;
}
}
while(session->state == FNET_TELNET_STATE_CLOSING);
}
}
