2 dns.h - dns library declarations based on firedns Copyright (C) 2002 Ian Gulliver
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21 #include <sys/types.h>
22 #include <sys/socket.h>
23 #include <netinet/in.h>
32 /** The DNS class allows fast nonblocking resolution of hostnames
33 * and ip addresses. It is based heavily upon firedns by Ian Gulliver.
44 void dns_init_2(const char* dnsserver);
45 in_addr *dns_aton4(const char * const ipstring);
46 char *dns_ntoa4(const in_addr * const ip);
47 int dns_getip4(const char * const name);
48 int dns_getip4list(const char * const name);
49 int dns_getname4(const in_addr * const ip);
50 char *dns_getresult(const int fd);
51 in_addr *dns_aton4_s(const char * const ipstring, in_addr * const ip);
52 char *dns_ntoa4_s(const in_addr * const ip, char * const result);
53 char *dns_getresult_s(const int fd, char * const result);
54 in_addr *dns_aton4_r(const char * const ipstring);
55 char *dns_ntoa4_r(const in_addr * const ip);
56 char *dns_getresult_r(const int fd);
58 /** The default constructor uses dns addresses read from /etc/resolv.conf.
59 * Please note that it will re-read /etc/resolv.conf for each copy of the
60 * class you instantiate, causing disk access and slow lookups if you create
61 * a lot of them. Consider passing the constructor a server address as a parameter
65 /** This constructor accepts a dns server address. The address must be in dotted
66 * decimal form, e.g. 1.2.3.4.
68 DNS(std::string dnsserver);
69 /** The destructor frees all used structures.
72 /** This method will start the reverse lookup of an ip given in dotted decimal
73 * format, e.g. 1.2.3.4, and returns true if the lookup was successfully
76 bool ReverseLookup(std::string ip);
77 /** This method will start the forward lookup of a hostname, e.g. www.inspircd.org,
78 * and returns true if the lookup was successfully initiated.
80 bool ForwardLookup(std::string host);
81 /** This method will return true when the lookup is completed. It uses poll internally
82 * to determine the status of the socket.
85 /** This method will return true if the lookup's fd matches the one provided
87 bool HasResult(int fd);
88 /** This method returns the result of your query as a string, depending upon wether you
89 * called DNS::ReverseLookup() or DNS::ForwardLookup.
91 std::string GetResult();
92 std::string GetResultIP();
93 /** This method returns the file handle used by the dns query socket or zero if the
94 * query is invalid for some reason, e.g. the dns server not responding.
97 void SetNS(std::string dnsserver);
100 /** This is the handler function for multi-threaded DNS.
101 * It cannot be a class member as pthread will not let us
102 * create a thread whos handler function is a member of
105 void* dns_task(void* arg);