diff options
author | brain <brain@e03df62e-2008-0410-955e-edbf42e46eb7> | 2007-01-09 22:31:19 +0000 |
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committer | brain <brain@e03df62e-2008-0410-955e-edbf42e46eb7> | 2007-01-09 22:31:19 +0000 |
commit | 49e34a508d9070097fa6aae5bf611bdd5c2b0f2d (patch) | |
tree | c7b9ff06ae48b628a51515fe33e76daf362109c9 /include/dns.h | |
parent | d569a50e74b431008d00740723e7189004d01fca (diff) |
Comment on a lot of recently added stuff that wasnt properly documented (until now)
git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@6284 e03df62e-2008-0410-955e-edbf42e46eb7
Diffstat (limited to 'include/dns.h')
-rw-r--r-- | include/dns.h | 63 |
1 files changed, 59 insertions, 4 deletions
diff --git a/include/dns.h b/include/dns.h index 562a49322..6913527ae 100644 --- a/include/dns.h +++ b/include/dns.h @@ -55,11 +55,25 @@ class Module; class DNSResult : public classbase { public: + /** Result ID + */ int id; + /** Result body, a hostname or IP address + */ std::string result; + /** Time-to-live value of the result + */ unsigned long ttl; + /** The original request, a hostname or IP address + */ std::string original; + /** Build a DNS result. + * @param i The request ID + * @param res The request result, a hostname or IP + * @param timetolive The request time-to-live + * @param orig The original request, a hostname or IP + */ DNSResult(int i, const std::string &res, unsigned long timetolive, const std::string &orig) : id(i), result(res), ttl(timetolive), original(orig) { } }; @@ -68,19 +82,30 @@ class DNSResult : public classbase */ typedef std::pair<unsigned char*, std::string> DNSInfo; -/** Cached item +/** Cached item stored in the query cache. */ class CachedQuery { public: + /** The cached result data, an IP or hostname + */ std::string data; + /** The time when the item is due to expire + */ time_t expires; + /** Build a cached query + * @param res The result data, an IP or hostname + * @param ttl The time-to-live value of the query result + */ CachedQuery(const std::string &res, unsigned int ttl) : data(res) { expires = time(NULL) + ttl; } + /** Returns the number of seconds remaining before this + * cache item has expired and should be removed. + */ int CalcTTLRemaining() { int n = expires - time(NULL); @@ -88,7 +113,7 @@ class CachedQuery } }; -/** DNS cache information +/** DNS cache information. Holds IPs mapped to hostnames, and hostnames mapped to IPs. */ typedef nspace::hash_map<irc::string, CachedQuery, nspace::hash<irc::string> > dnscache; @@ -277,12 +302,15 @@ class Resolver : public Extensible * this method will return -1. */ int GetId(); - /** * Returns the creator module, or NULL */ Module* GetCreator(); - + /** + * If the result is a cached result, this triggers the objects + * OnLookupComplete. This is done because it is not safe to call + * the abstract virtual method from the constructor. + */ void TriggerCachedResult(); }; @@ -295,6 +323,9 @@ class DNS : public EventHandler { private: + /** + * Creator/Owner object + */ InspIRCd* ServerInstance; /** @@ -326,6 +357,9 @@ class DNS : public EventHandler */ dnscache* cache; + /** A timer which ticks every hour to remove expired + * items from the DNS cache. + */ class CacheTimer* PruneTimer; /** @@ -334,14 +368,17 @@ class DNS : public EventHandler int MakePayload(const char* name, const QueryType rr, const unsigned short rr_class, unsigned char* payload); public: + /** * Currently active Resolver classes */ Resolver* Classes[MAX_REQUEST_ID]; + /** * Requests that are currently 'in flight' */ DNSRequest* requests[MAX_REQUEST_ID]; + /** * The port number DNS requests are made on, * and replies have as a source-port number. @@ -352,14 +389,17 @@ class DNS : public EventHandler * Fill an rr (resource record) with data from input */ static void FillResourceRecord(ResourceRecord* rr, const unsigned char* input); + /** * Fill a header with data from input limited by a length */ static void FillHeader(DNSHeader *header, const unsigned char *input, const int length); + /** * Empty out a header into a data stream ready for transmission "on the wire" */ static void EmptyHeader(unsigned char *output, const DNSHeader *header, const int length); + /** * Start the lookup of an ipv4 from a hostname */ @@ -447,11 +487,26 @@ class DNS : public EventHandler */ void CleanResolvers(Module* module); + /** Return the cached value of an IP or hostname + * @param source An IP or hostname to find in the cache. + * @return A pointer to a CachedQuery if the item exists, + * otherwise NULL. + */ CachedQuery* GetCache(const std::string &source); + /** Delete a cached item from the DNS cache. + * @param source An IP or hostname to remove + */ void DelCache(const std::string &source); + /** Clear all items from the DNS cache immediately. + */ int ClearCache(); + + /** Prune the DNS cache, e.g. remove all expired + * items and rehash the cache buckets, but leave + * items in the hash which are still valid. + */ int PruneCache(); }; |