Diff: cyclone_tcp/dns/dns_cache.h

Revision:

0:8918a71cdbe9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cyclone_tcp/dns/dns_cache.h	Sat Feb 04 18:15:49 2017 +0000
@@ -0,0 +1,125 @@
+/**
+ * @file dns_cache.h
+ * @brief DNS cache management
+ *
+ * @section License
+ *
+ * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
+ *
+ * This file is part of CycloneTCP Open.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * @author Oryx Embedded SARL (www.oryx-embedded.com)
+ * @version 1.7.6
+ **/
+
+#ifndef _DNS_CACHE_H
+#define _DNS_CACHE_H
+
+//Dependencies
+#include "core/net.h"
+#include "core/socket.h"
+
+//DNS tick interval
+#ifndef DNS_TICK_INTERVAL
+   #define DNS_TICK_INTERVAL 200
+#elif (DNS_TICK_INTERVAL < 10)
+   #error DNS_TICK_INTERVAL parameter is not valid
+#endif
+
+//Size of DNS cache
+#ifndef DNS_CACHE_SIZE
+   #define DNS_CACHE_SIZE 8
+#elif (DNS_CACHE_SIZE < 1)
+   #error DNS_CACHE_SIZE parameter is not valid
+#endif
+
+//Maximum length of domain names
+#ifndef DNS_MAX_NAME_LEN
+   #define DNS_MAX_NAME_LEN 63
+#elif (DNS_MAX_NAME_LEN < 1)
+   #error DNS_MAX_NAME_LEN parameter is not valid
+#endif
+
+//Initial polling interval
+#ifndef DNS_CACHE_INIT_POLLING_INTERVAL
+   #define DNS_CACHE_INIT_POLLING_INTERVAL 10
+#elif (DNS_CACHE_INIT_POLLING_INTERVAL < 1)
+   #error DNS_CACHE_INIT_POLLING_INTERVAL parameter is not valid
+#endif
+
+//Maximum polling interval
+#ifndef DNS_CACHE_MAX_POLLING_INTERVAL
+   #define DNS_CACHE_MAX_POLLING_INTERVAL 1000
+#elif (DNS_CACHE_MAX_POLLING_INTERVAL < 10)
+   #error DNS_CACHE_MAX_POLLING_INTERVAL parameter is not valid
+#endif
+
+
+/**
+ * @brief DNS cache entry states
+ **/
+
+typedef enum
+{
+   DNS_STATE_NONE        = 0,
+   DNS_STATE_IN_PROGRESS = 1,
+   DNS_STATE_RESOLVED    = 2,
+   DNS_STATE_PERMANENT   = 3
+} DnsState;
+
+
+/**
+ * @brief DNS cache entry
+ **/
+
+typedef struct
+{
+   DnsState state;                    ///<Entry state
+   HostType type;                     ///<IPv4 or IPv6 host?
+   HostnameResolver protocol;         ///<Name resolution protocol
+   NetInterface *interface;           ///<Underlying network interface
+   uint_t dnsServerNum;               ///<This parameter selects between the primary and secondary DNS server
+   uint16_t port;                     ///<Port number used by the resolver
+   uint16_t id;                       ///<Identifier used to match queries and responses
+   char_t name[DNS_MAX_NAME_LEN + 1]; ///<Domain name
+   IpAddr ipAddr;                     ///<IP address
+   systime_t timestamp;               ///<Time stamp to manage entry lifetime
+   systime_t timeout;                 ///<Retransmission timeout
+   systime_t maxTimeout;              ///<Maximum retransmission timeout
+   uint_t retransmitCount;            ///<Retransmission counter
+} DnsCacheEntry;
+
+
+//Global variables
+extern systime_t dnsTickCounter;
+extern DnsCacheEntry dnsCache[DNS_CACHE_SIZE];
+
+//DNS related functions
+error_t dnsInit(void);
+
+void dnsFlushCache(NetInterface *interface);
+
+DnsCacheEntry *dnsCreateEntry(void);
+void dnsDeleteEntry(DnsCacheEntry *entry);
+
+DnsCacheEntry *dnsFindEntry(NetInterface *interface,
+   const char_t *name, HostType type, HostnameResolver protocol);
+
+void dnsTick(void);
+
+#endif
+