Diff: if/lwip/lwipNetDnsRequest.cpp

Revision:

0:350011bf8be7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/if/lwip/lwipNetDnsRequest.cpp	Tue Nov 23 14:15:36 2010 +0000
@@ -0,0 +1,152 @@
+
+/*
+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), m_closing(false)
+{
+  DBG("New LwipNetDnsRequest %p\n", this);
+}
+
+LwipNetDnsRequest::LwipNetDnsRequest(Host* pHost) : NetDnsRequest(pHost), m_state(LWIPNETDNS_START), m_cbFired(false), m_closing(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; 
+  }
+  if(m_closing && (m_state!=LWIPNETDNS_PROCESSING)) //Check wether the closure has been reqd
+  {
+    DBG("LwipNetDnsRequest: Closing in poll()\n");
+    NetDnsRequest::close();
+  }
+}
+
+void LwipNetDnsRequest::close()
+{
+  DBG("LwipNetDnsRequest: Close req\n");
+  if(m_state!=LWIPNETDNS_PROCESSING)
+  {
+    DBG("LwipNetDnsRequest: Closing in close()\n");
+    NetDnsRequest::close();
+  }
+  else //Cannot close rightaway, waiting for callback from underlying layer
+  {
+    m_closing = true;
+  }
+}
+
+void LwipNetDnsRequest::foundCb(const char *name, ip_addr_t *ipaddr)
+{
+  if( ipaddr == NULL )
+  {
+    DBG("LwipNetDnsRequest: Callback: Name not found\n");
+    m_state = LWIPNETDNS_NOTFOUND;
+    return;
+  }
+  DBG("LwipNetDnsRequest: Callback: Resolved\n");
+  m_ip = IpAddr(ipaddr);
+  m_state = LWIPNETDNS_OK;
+}
+
+
+void LwipNetDnsRequest::sFoundCb(const char *name, ip_addr_t *ipaddr, void *arg)
+{
+  DBG("LwipNetDnsRequest: Static callback\n");
+  LwipNetDnsRequest* pMe = (LwipNetDnsRequest*) arg;
+  return pMe->foundCb( name, ipaddr );
+}
+
+#endif
+