1 (in-package :sb-bsd-sockets)
2 #|| <a name="name-service"><h2>Name Service</h2></a>
4 <p>Presently name service is implemented by calling whatever
5 gethostbyname(2) uses. This may be any or all of /etc/hosts, NIS, DNS,
6 or something completely different. Typically it's controlled by
9 <p> Direct links to the asynchronous resolver(3) routines would be nice to have
10 eventually, so that we can do DNS lookups in parallel with other things
14 ((name :initarg :name :accessor host-ent-name)
15 (aliases :initarg :aliases :accessor host-ent-aliases)
16 (address-type :initarg :type :accessor host-ent-address-type)
17 ; presently always AF_INET
18 (addresses :initarg :addresses :accessor host-ent-addresses)))
20 (defgeneric host-ent-address (host-ent))
22 (defmethod host-ent-address ((host-ent host-ent))
23 (car (host-ent-addresses host-ent)))
25 ;(define-condition host-not-found-error (socket-error)) ; host unknown
26 ;(define-condition no-address-error (socket-error)) ; valid name but no IP address
27 ;(define-condition no-recovery-error (socket-error)) ; name server error
28 ;(define-condition try-again-error (socket-error)) ; temporary
30 (defun get-host-by-name (host-name)
31 "Returns a HOST-ENT instance for HOST-NAME or throws some kind of condition.
32 HOST-NAME may also be an IP address in dotted quad notation or some other
33 weird stuff - see gethostbyname(3) for grisly details."
34 (let ((h (sockint::gethostbyname host-name)))
37 (defun get-host-by-address (address)
38 "Returns a HOST-ENT instance for ADDRESS, which should be a vector of
39 (integer 0 255), or throws some kind of error. See gethostbyaddr(3) for
41 (let ((packed-addr (sockint::allocate-in-addr)))
42 (loop for i from 0 to 3
43 do (setf (sockint::in-addr-addr packed-addr i) (elt address i)))
46 (sockint::gethostbyaddr (sockint::array-data-address packed-addr)
50 (defun make-host-ent (h)
51 (if (sockint::foreign-nullp h) (name-service-error "gethostbyname"))
52 (let* ((local-h (sockint::foreign-vector h 1 sockint::size-of-hostent))
53 (length (sockint::hostent-length local-h))
55 (loop for i = 0 then (1+ i)
56 for al = (sb-sys:sap-ref-sap
57 (sb-sys:int-sap (sockint::hostent-aliases local-h))
59 until (= (sb-sys:sap-int al) 0)
60 collect (sb-c-call::%naturalize-c-string al)))
61 (address0 (sb-sys:sap-ref-sap (sb-sys:int-sap (sockint::hostent-addresses local-h)) 0))
63 (loop for i = 0 then (+ length i)
64 for ad = (sb-sys:sap-ref-32 address0 i)
67 (sockint::foreign-vector (sb-sys:sap+ address0 i) 1 length))))
68 (make-instance 'host-ent
69 :name (sb-c-call::%naturalize-c-string
70 (sb-sys:int-sap (sockint::hostent-name local-h)))
71 :type (sockint::hostent-type local-h)
73 :addresses addresses)))
75 ;;; The remainder is my fault - gw
77 (defvar *name-service-errno* 0
78 "The value of h_errno, after it's been fetched from Unix-land by calling
79 GET-NAME-SERVICE-ERRNO")
81 (defun name-service-error (where)
82 (get-name-service-errno)
83 ;; Comment next to NETDB_INTERNAL in netdb.h says "See errno.".
84 ;; This special case treatment hasn't actually been tested yet.
85 (if (= *name-service-errno* sockint::NETDB-INTERNAL)
88 (condition-for-name-service-errno *name-service-errno*)))
89 (error condition :errno *name-service-errno* :syscall where))))
91 (define-condition name-service-error (condition)
94 :reader name-service-error-errno)
95 (symbol :initform nil :initarg :symbol :reader name-service-error-symbol)
96 (syscall :initform "an unknown location" :initarg :syscall :reader name-service-error-syscall))
97 (:report (lambda (c s)
98 (let ((num (name-service-error-errno c)))
99 (format s "Name service error in \"~A\": ~A (~A)"
100 (name-service-error-syscall c)
101 (or (name-service-error-symbol c)
102 (name-service-error-errno c))
103 (get-name-service-error-message num))))))
105 (defmacro define-name-service-condition (symbol name)
107 (define-condition ,name (name-service-error)
108 ((symbol :reader name-service-error-symbol :initform (quote ,symbol))))
109 (push (cons ,symbol (quote ,name)) *conditions-for-name-service-errno*)))
111 (defparameter *conditions-for-name-service-errno* nil)
113 (define-name-service-condition sockint::NETDB-INTERNAL netdb-internal-error)
114 (define-name-service-condition sockint::NETDB-SUCCESS netdb-success-error)
115 (define-name-service-condition sockint::HOST-NOT-FOUND host-not-found-error)
116 (define-name-service-condition sockint::TRY-AGAIN try-again-error)
117 (define-name-service-condition sockint::NO-RECOVERY no-recovery-error)
118 ;; this is the same as the next one
119 ;;(define-name-service-condition sockint::NO-DATA no-data-error)
120 (define-name-service-condition sockint::NO-ADDRESS no-address-error)
122 (defun condition-for-name-service-errno (err)
123 (or (cdr (assoc err *conditions-for-name-service-errno* :test #'eql))
128 (defun get-name-service-errno ()
129 (setf *name-service-errno*
130 (sb-alien:alien-funcall
131 (sb-alien:extern-alien "get_h_errno" (function integer)))))
136 (sb-alien:define-alien-routine "hstrerror"
140 (alien:def-alien-routine "hstrerror"
143 (defun get-name-service-error-message (num)