Thanks Tony. I may have spoken too soon, it seems the issue I’m having is a little deeper. Changing SO_REUSE just make it less apparent in that particular test case.
This could all boil down to what I expect ‘send’ and ‘recv’ to do on disconnect. A stripped down test case is below. Please excuse the messy code.
I expect that on a closed socket (or closing socket), send and recv will return without performing any functions until I have a chance to synchronize the two threads. You can see my method of doing that below.
Instead, both the server (recv) and transmit (send) tasks stay in their respective send/recv functions, without indication that the socket has closed. The socket is still marked as ESTABLISHED in both functions when this happens. Server task priority is 2, transmit task priority is 1, and IP task priority is 3 (network driver layer is 4).
I have a packet capture of what happens (and the resulting stack trace in a debugger), and it’s fairly easy for me to reproduce (I can’t upload the actual capture, so a screenshot will have to do for now).
struct ServerTaskParams {
StreamBufferHandle_t rx_stream;
volatile Socket_t socket;
MessageBufferHandle_t adc_msg_buff;
TaskHandle_t server_task;
uint32_t tx_task_exit;
};
static struct ServerTaskParams server_params;
__BSS(BOARD_SDRAM) uint8_t data[125000];
void ServerTxTask(void* params){
struct ServerTaskParams * serv_params = (struct ServerTaskParams *)params;
BaseType_t res;
while(1){
res = FreeRTOS_send(serv_params->socket,data,125000,0);
if(res != 125000) PRINTF("Here\n\n");
if(res < 0 || serv_params->tx_task_exit){
xTaskNotifyGive(serv_params->server_task);
vTaskSuspend(NULL);
}
}
}
void ServerTask(void* params){
Socket_t xListeningSocket;
TickType_t xReceiveTimeOut = portMAX_DELAY;
BaseType_t res=1;
struct freertos_sockaddr xClient, xBindAddress;
uint32_t xSize = sizeof(xClient);
uint8_t data[8];
struct ServerTaskParams * serv_params = (struct ServerTaskParams *)params;
TaskHandle_t serv_tx_handle;
serv_params->socket = NULL;
xListeningSocket = FreeRTOS_socket(FREERTOS_AF_INET4,FREERTOS_SOCK_STREAM,FREERTOS_IPPROTO_TCP );
FreeRTOS_setsockopt(xListeningSocket,0,FREERTOS_SO_RCVTIMEO,&xReceiveTimeOut,sizeof(xReceiveTimeOut));
//res = 1;
//FreeRTOS_setsockopt(xListeningSocket,0,FREERTOS_SO_REUSE_LISTEN_SOCKET,&res,sizeof(res));
xBindAddress.sin_port = FreeRTOS_htons(5911);
xBindAddress.sin_family = FREERTOS_AF_INET4;
FreeRTOS_bind(xListeningSocket,&xBindAddress,sizeof(xBindAddress));
FreeRTOS_listen(xListeningSocket,1);
while(1){
serv_params->socket = FreeRTOS_accept(xListeningSocket,&xClient, &xSize);
data[0] = 'U';
FreeRTOS_send(serv_params->socket,data,1,0);
serv_params->tx_task_exit = 0;
xTaskCreate(ServerTxTask,"SERV_TX",256,serv_params,1,&serv_tx_handle);
do{
res = FreeRTOS_recv(serv_params->socket,&data,sizeof(data),0);
if(res >= 0) xStreamBufferSend(serv_params->rx_stream,&data,res,0);
}while(res >= 0);
//An error (receive result < 0) means we should disconnect and re-start listening
FreeRTOS_shutdown(serv_params->socket,FREERTOS_SHUT_RDWR);
serv_params->tx_task_exit = 1;
ulTaskNotifyTake(pdTRUE,portMAX_DELAY); //wait for tx task completion
vTaskDelete(serv_tx_handle);
FreeRTOS_closesocket(serv_params->socket);
serv_params->socket = NULL;
}
}
void Network_Init(void){
server_params.rx_stream = xStreamBufferCreate(128,1);
xTaskCreate(ServerTask,"SERVER",128*2,&server_params,2,&server_params.server_task);
}
