Example program with HTTPServer and sensor data streaming over TCPSockets, using Donatien Garnier's Net APIs and services code on top of LWIP. Files StreamServer.h and .cpp encapsulate streaming over TCPSockets. Broadcast is done by sendToAll(), and all incoming data is echoed back to the client. Echo code can be replaced with some remote control of the streaming interface. See main() that shows how to periodically send some data to all subscribed clients. To subscribe, a client should open a socket at <mbed_ip> port 123. I used few lines in TCL code to set up a quick sink for the data. HTTP files are served on port 80 concurrently to the streaming.
Diff: if/lwip/lwipNetDnsRequest.cpp
- Revision:
- 0:e614f7875b60
diff -r 000000000000 -r e614f7875b60 if/lwip/lwipNetDnsRequest.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/if/lwip/lwipNetDnsRequest.cpp Sat Jun 12 06:01:50 2010 +0000 @@ -0,0 +1,131 @@ + +/* +Copyright (c) 2010 Donatien Garnier (donatiengar [at] gmail [dot] com) + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. +*/ + +#include "lwipNetDnsRequest.h" +#include "lwip/err.h" //err_t, ERR_xxx +#include "lwip/dns.h" + +#include "netCfg.h" +#if NET_LWIP_STACK + +//#define __DEBUG +#include "dbg/dbg.h" + +LwipNetDnsRequest::LwipNetDnsRequest(const char* hostname) : NetDnsRequest(hostname), m_state(LWIPNETDNS_START), m_cbFired(false) +{ + DBG("New LwipNetDnsRequest %p\n", this); +} + +LwipNetDnsRequest::LwipNetDnsRequest(Host* pHost) : NetDnsRequest(pHost), m_state(LWIPNETDNS_START), m_cbFired(false) +{ + DBG("New LwipNetDnsRequest %p\n", this); +} + +LwipNetDnsRequest::~LwipNetDnsRequest() +{ + DBG("LwipNetDnsRequest %p destroyed\n", this); +} + +/* +Main useful function here (see lwip/dns.h): +err_t dns_gethostbyname(const char *hostname, ip_addr_t *addr, + dns_found_callback found, void *callback_arg); +*/ + +//Execute request & return OK if found, NOTFOUND or ERROR on error, or PROCESSING if the request has not completed yet +void LwipNetDnsRequest::poll() +{ + err_t err; + switch(m_state) + { + case LWIPNETDNS_START: //First req, let's call dns_gethostbyname + ip_addr_t ipStruct; + err = dns_gethostbyname(m_hostname, &ipStruct, LwipNetDnsRequest::sFoundCb, (void*) this ); + if( err == ERR_OK ) + { + m_ip = IpAddr(&ipStruct); + m_state = LWIPNETDNS_OK; + DBG("DNS: Ip found in cache.\n"); + } + else if( err == ERR_INPROGRESS) + { + DBG("DNS: Processing.\n"); + m_state = LWIPNETDNS_PROCESSING; + } + else //Likely ERR_VAL + { + DBG("DNS: Error on init.\n"); + m_state = LWIPNETDNS_ERROR; + } + break; + case LWIPNETDNS_PROCESSING: + break; //Nothing to do, DNS is polled on interrupt + case LWIPNETDNS_OK: + if(!m_cbFired) + { + DBG("DNS: Ip found.\n"); + m_cbFired = true; + onReply(NETDNS_FOUND); //Raise callback + } + break; + case LWIPNETDNS_NOTFOUND: + if(!m_cbFired) + { + DBG("DNS: could not be resolved.\n"); + m_cbFired = true; + onReply(NETDNS_NOTFOUND); //Raise callback + } + break; + case LWIPNETDNS_ERROR: + default: + if(!m_cbFired) + { + DBG("DNS: Error.\n"); + m_cbFired = true; + onReply(NETDNS_ERROR); //Raise callback + } + break; + } +// return m_state; +} + +void LwipNetDnsRequest::foundCb(const char *name, ip_addr_t *ipaddr) +{ + if( ipaddr == NULL ) + { + m_state = LWIPNETDNS_NOTFOUND; + return; + } + m_ip = IpAddr(ipaddr); + m_state = LWIPNETDNS_OK; +} + + +void LwipNetDnsRequest::sFoundCb(const char *name, ip_addr_t *ipaddr, void *arg) +{ + LwipNetDnsRequest* pMe = (LwipNetDnsRequest*) arg; + return pMe->foundCb( name, ipaddr ); +} + +#endif +