Christoph:
Deal with mult-connection correctly, there is 3 way.
1.
Using raw api
2.
Using netconn API, but you have to create a task to handle the HTTP request, then back to main thread to start accept next request.
3.
Using socket, you must set it with non-blocking and select it
I use the 3th method. The following code must be add to listen socket.
Int arg = 0x1;
lwip_ioctl(listhensocket, FIONBIO, &arg);
but I found that the listen socket cann’t work once it is set with nonblocking…
now, I remove it, it works … hope someone explain why
other, you also need call lwIP_shutdown and lowip_close to terminate socket in order to be avoid to CLOSE_WAIT .
Vincent Cui
Sr.Firmware Engineer
Mobile: +8613482482211
Tel: +86 21 34612525x6104
Fax: +86 21 34619770
E-Mail: address@hidden
Shanghai EnLogic Electric Technology Co., Ltd.
Address: 1104-1106, Building A, No.391, Guiping Road, Xuhui District, Shanghai, 200233
http://www.enlogic.com
From: lwip-users-bounces+address@hidden [mailto:lwip-users-bounces+address@hidden
On Behalf Of Christoph Kronen
Sent: 2011年8月30日
15:31
To: Mailing list for lwIP users
Subject: Re: [lwip-users] FreeRTOS / lwip multiple connections
Hi Vincent,
I changed the receiving process to be nonblocking, it wasn't like this in the first place. The code below has the same entry point as your "vHandler_HTTP(__pstNewConn);", it gets called when the connection is already established.
My problem was the following: I needed to check for new data received via Ethernet as well as new data from a Sendqueue in the same task. So netconn_recv() could not be blocking. In another topic, Simon Goldschmitt suggested to use lwIP 1.3.1 and to set "LWIP_SO_RCVTIMEO"
to make netconn_recv() nonblocking. Unfortunately this crashed my Sam7X all the time.
So what I do now, is to peek into the receive mailbox and only if there is data I start the netconn_recv() process. Probably horrible programming, but it works for now.
Richard suggested to use semaphores on TCP events, that sounds much cleaner and I will definitely try to do it that way. But then I would need a FreeRTOS function like "WaitForMultipleObjects", since the Task needs to wake up for either a TCP event semaphore
OR a new element in my SendQueue.
The CommandInterpreter from Richards socket example (thanks !) works for my Sam7X and I am in the process of rewriting it to have the same functionality as the code below.
@Vincent: You said your webserver is able to have multiple connections, could you give me a tip on that ? Do you have a small code example for "multiconnection socket" part ?
Thank you very much,
Christoph
static void vProcessSpeedtest( struct netconn *pxNetCon )
{
struct netbuf *pxRxBuffer;
struct pbuf *dummybuffer;
unsigned char *pcRxString;
xTCP_TXBuff * TXPointer = 0;
unsigned short usLength;
while (1)
{
// Peek into the Receive mailbox
if ( pdTRUE == xQueuePeek((pxNetCon->recvmbox),&dummybuffer,0))
{
pxRxBuffer = netconn_recv( pxNetCon );
if( pxRxBuffer != NULL )
{
do
{
netbuf_data( pxRxBuffer, ( void * ) &pcRxString, &usLength );
//use the incoming data at this point
} while ( netbuf_next(pxRxBuffer) >=0 );
netbuf_delete( pxRxBuffer );
}
else break;
}
// Check the Transmit Queue for Data and send it
if ( xQueueReceive( xTXPointerQueue, &TXPointer, 0 ))
{
netconn_write(pxNetCon, TXPointer->data, TXPointer->length, NETCONN_NOFLAG);
vFreeTCPBuffer(TXPointer);
}
vTaskDelay( 1 / portTICK_RATE_MS );
}
netconn_close( pxNetCon );
}
-------- Original-Nachricht --------
Datum: Tue, 30 Aug 2011 03:28:07 +0000
Von: vincent cui <address@hidden>
An: Mailing list for lwIP users <address@hidden>
Betreff: Re: [lwip-users] FreeRTOS / lwip multiple connections
Hi Chistoph:
The "lwIP Embedded Webserver Demo" is what I took as a starting point. I removed the webserver functionality, now I have a task that
-
checks for incoming data (nonblocking)
-
checks a Queue for outgoing data (nonblocking)
-
wait 1 ms (to prevent 100% cpu usage)
the LwIP webserver demo code is following, I don’t know how do you infer it is noblocking for incoming data and outgoing ….
Where to wait 1 ms .
void WebServer_Handler(void *pdata)
{
struct netconn *__pstConn, *__pstNewConn;
__pstConn = netconn_new(NETCONN_TCP);
netconn_bind(__pstConn, NULL,80);
netconn_listen(__pstConn);
for(;;)
{
__pstNewConn = netconn_accept(__pstConn);
if(__pstNewConn != NULL)
{
vHandler_HTTP(__pstNewConn);
while(netconn_delete(__pstNewConn) != ERR_OK)
{
vTaskDelay(10);
}
}
}
}
Vincent Cui
Sr.Firmware Engineer
Mobile: +8613482482211
Tel: +86 21 34612525x6104
Fax: +86 21 34619770
E-Mail:
address@hidden
Shanghai EnLogic Electric Technology Co., Ltd.
Address: 1104-1106, Building A, No.391, Guiping Road, Xuhui District, Shanghai, 200233
http://www.enlogic.com
Hi all,
I am using FreeRTOS 7.0.1 on a Sam7X512 and upgraded the contributed port lwIP 1.3.0 to 1.3.2.
The "lwIP Embedded Webserver Demo" is what I took as a starting point. I removed the webserver functionality, now I have a task that
-
checks for incoming data (nonblocking)
-
checks a Queue for outgoing data (nonblocking)
-
wait 1 ms (to prevent 100% cpu usage)
This works pretty well, I get around 1400 kbyte/s RX and TX.
Now to my question: Is it possible/difficult/easy to transform this functionality to accept multiple connections on the same port ? At the moment I am using the netconn API, so I guess I have to switch to the Socket API ?
I read through Richards thread on his "FreeRTOS/lwip Win32 simulator" project and it sounds as if it is quite difficult to have multiple connections in a multithreaded environment. Unfortunately I could not find other helpful topics or contributed examples.
I am rather new to FreeRTOS and lwIP, so please excuse me if I am missing something obvious :-)
Please give me some comments / suggestions / tips / pushes into the right direction.
Thank you very much !
Christoph