2 dns.h - dns library declarations based on firedns Copyright (C) 2002 Ian Gulliver
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11 GNU General Public License for more details.
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22 #include "inspircd_config.h"
36 RESOLVER_NXDOMAIN = 2,
41 /** The DNS class allows fast nonblocking resolution of hostnames
42 * and ip addresses. It is based heavily upon firedns by Ian Gulliver.
44 class DNS : public Extensible
53 void dns_init_2(const char* dnsserver);
54 in_addr *dns_aton4(const char * const ipstring);
55 char *dns_ntoa4(const in_addr * const ip);
56 int dns_getip4(const char * const name);
57 int dns_getip4list(const char * const name);
58 int dns_getname4(const in_addr * const ip);
59 char *dns_getresult(const int fd);
60 in_addr *dns_aton4_s(const char * const ipstring, in_addr * const ip);
61 char *dns_ntoa4_s(const in_addr * const ip, char * const result);
62 char *dns_getresult_s(const int fd, char * const result);
63 in_addr *dns_aton4_r(const char * const ipstring);
64 char *dns_ntoa4_r(const in_addr * const ip);
65 char *dns_getresult_r(const int fd);
67 /** The default constructor uses dns addresses read from /etc/resolv.conf.
68 * Please note that it will re-read /etc/resolv.conf for each copy of the
69 * class you instantiate, causing disk access and slow lookups if you create
70 * a lot of them. Consider passing the constructor a server address as a parameter
74 /** This constructor accepts a dns server address. The address must be in dotted
75 * decimal form, e.g. 1.2.3.4.
77 DNS(const std::string &dnsserver);
78 /** The destructor frees all used structures.
81 /** This method will start the reverse lookup of an ip given in dotted decimal
82 * format, e.g. 1.2.3.4, and returns true if the lookup was successfully
85 bool ReverseLookup(const std::string &ip);
86 /** This method will start the forward lookup of a hostname, e.g. www.inspircd.org,
87 * and returns true if the lookup was successfully initiated.
89 bool ForwardLookup(const std::string &host);
90 /** Used by modules to perform a dns lookup but have the socket engine poll a module, instead of the dns object directly.
92 bool ForwardLookupWithFD(const std::string &host, int &fd);
93 /** This method will return true when the lookup is completed. It uses poll internally
94 * to determine the status of the socket.
97 /** This method will return true if the lookup's fd matches the one provided
99 bool HasResult(int fd);
100 /** This method returns the result of your query as a string, depending upon wether you
101 * called DNS::ReverseLookup() or DNS::ForwardLookup.
103 std::string GetResult();
104 std::string GetResultIP();
105 /** This method returns the file handle used by the dns query socket or zero if the
106 * query is invalid for some reason, e.g. the dns server not responding.
109 void SetNS(const std::string &dnsserver);
112 class Resolver : public Extensible
122 Resolver(const std::string &source, bool forward, const std::string &dnsserver);
124 virtual void OnLookupComplete(const std::string &result);
125 virtual void OnError(ResolverError e);
127 bool ProcessResult();
132 void dns_deal_with_classes(int fd);
133 bool dns_add_class(Resolver* r);
135 /** This is the handler function for multi-threaded DNS.
136 * It cannot be a class member as pthread will not let us
137 * create a thread whos handler function is a member of
140 void* dns_task(void* arg);