The record types we support.

The status codes recognized by ADNS vary in different versions of the library. So instead of providing an Enum, the Status type contains the numeric value as returned by ADNS itself. For common status codes, helper functions like sOK or sNXDOMAIN are provided. The functions adnsErrTypeAbbrev, adnsErrAbbrev, and adnsStrerror can also be used to map these codes into human readable strings.

Original definition:

   typedef struct {
     int len;
     union {
       struct sockaddr sa;
       struct sockaddr_in inet;
     } addr;
   } adns_rr_addr;

Note: Anything but sockaddr_in will cause peek to call fail, when marshaling this structure. poke is not defined.

Original definition:

   typedef struct {
     char *host;
     adns_status astatus;
     int naddrs; /* temp fail => -1, perm fail => 0, s_ok => >0
     adns_rr_addr *addrs;
   } adns_rr_hostaddr;

The naddrs field is not available in RRHostAddr because I couldn't see how that information wouldn't be available in the astatus field too. If I missed anything, please let me know.

Note: The data type should probably contain HostAddress rather than RRAddr. I'm using the former only because it has nicer output with show. poke is not defined.

Original definition:

   typedef struct {
     int i;
     adns_rr_hostaddr ha;
   } adns_rr_inthostaddr;

Original definition:

   typedef struct {
     int len;
     unsigned char *data;
   } adns_rr_byteblock;

Original definition:

   typedef struct {
     int priority, weight, port;
     char *host;
   } adns_rr_srvraw;

This function parses the Response union found in Answer. It cannot be defined via Storable because it needs to know the type of the record to expect. This is, by the way, the function to look at, if you want to add support for additional RRType records.

This function parses a FQDN in uncompressed wire format and advances the pointer to the next byte after the parsed name.

Run the given IO computation with an initialized resolver. As of now, the diagnose stream is always set to stderr. Initialize the library with NoErrPrint if you don't wont to see any error output. All resources are freed when adnsInit returns.

Similar to adnsInit, but reads the resolver configuration from a string rather than from /etc/resolv.conf. Supported are the usual commands: nameserver, search, domain, sortlist, and options.

Additionally, these non-standard commands may be used:

• clearnameservers: Clears the list of nameservers.
• include filename: The specified file will be read.

Perform a synchronous query for a record. In case of an I/O error, an IOException is thrown. If the query fails for other reasons, the Status code in the Answer will signify that.

Submit an asynchronous query. The returned Query can be tested for completion with adnsCheck.

Check the status of an asynchronous query. If the query is complete, the Answer will be returned. The Query becomes invalid after that.

Wait for a response to arrive. The returned Query is invalid and must not be passed to ADNS again. If Nothing is returned, the resolver is empty.

Cancel an open Query.

Wait for the next Query to become available.

Return the list of all currently open queries.

Map a Status code to a human-readable error description. For example:

   *ADNS> adnsStrerror sNXDOMAIN >>= print
   "No such domain"

Use this function with great care: It will crash the process when called with a status code that ADNS doesn't know about. So use it only to print values you got from the resolver!

Map a Status code to a short error name. Don't use this function to print a status code unless you've obtained it from the resolver!

Map a Status code to a short description of the type of error. Don't use this function to print a status code unless you've obtained it from the resolver!

Internel helper function to handle result passing from ADNS via Ptr (Ptr a), and to generate human-readable IO exceptions in case of an error.

Map a list of flags (Enum types) into a CInt suitable for adns calls.