1.0.42.14: socket-connect thread safety, version 2

[sbcl.git] / contrib / sb-bsd-sockets / inet.lisp

diff --git a/contrib/sb-bsd-sockets/inet.lisp b/contrib/sb-bsd-sockets/inet.lisp
index 869b80f..351251f 100644 (file)
--- a/contrib/sb-bsd-sockets/inet.lisp
+++ b/contrib/sb-bsd-sockets/inet.lisp
@@ -64,17 +64,76 @@ Examples:
              (format s "Protocol not found: ~a" (prin1-to-string
                                                  (unknown-protocol-name c))))))
 
+#+(and sb-thread (not os-provides-getprotoby-r))
+;; Since getprotobyname is not thread-safe, we need a lock.
+(sb-ext:defglobal **getprotoby-lock** (sb-thread:make-mutex :name "getprotoby lock"))
+
 ;;; getprotobyname only works in the internet domain, which is why this
 ;;; is here
 (defun get-protocol-by-name (name)      ;exported
-  "Returns the network protocol number associated with the string NAME,
-using getprotobyname(2) which typically looks in NIS or /etc/protocols"
-  ;; for extra brownie points, could return canonical protocol name
-  ;; and aliases as extra values
-  (let ((ent (sockint::getprotobyname name)))
-    (if (sb-alien::null-alien ent)
-        (error 'unknown-protocol :name name))
-    (sockint::protoent-proto ent)))
+
+  ;; Brownie Points.  Hopefully there's one person out there using
+  ;; RSPF sockets and SBCL who will appreciate the extra info
+  (labels ((protoent-to-values (protoent)
+             (values
+              (sockint::protoent-proto protoent)
+              (sockint::protoent-name protoent)
+              (let ((index 0))
+                (loop
+                   for alias = (sb-alien:deref (sockint::protoent-aliases protoent) index)
+                   while (not (sb-alien:null-alien alias))
+                   do (incf index)
+                   collect (sb-alien::c-string-to-string (sb-alien:alien-sap alias)
+                                                         (sb-impl::default-external-format)
+                                                         'character))))))
+    #+(and sb-thread os-provides-getprotoby-r)
+    (let ((buffer-length 1024)
+          (max-buffer 10000))
+      (declare (type fixnum buffer-length)
+               (type fixnum max-buffer))
+      (loop
+         (sb-alien:with-alien ((result-buf (* sockint::protoent)
+                                           (sb-alien:make-alien sockint::protoent))
+                               (buffer (* char )
+                                       (sb-alien:make-alien sb-alien:char buffer-length))
+                               #-solaris
+                               (result (* (* sockint::protoent))
+                                       (sb-alien:make-alien (* sockint::protoent))))
+
+           (let ((res (sockint::getprotobyname-r name
+                                                 result-buf
+                                                 buffer
+                                                 buffer-length
+                                                 #-solaris
+                                                 result)))
+             (if (eql res 0)
+                 (progn
+                   #-solaris
+                   (when (sb-alien::null-alien (sb-alien:deref result 0))
+                     (error 'unknown-protocol :name name))
+                   (return-from get-protocol-by-name
+                     (protoent-to-values result-buf)))
+                 (let ((errno (sb-unix::get-errno)))
+                   (if (eql errno  sockint::erange)
+                       (progn
+                         (incf buffer-length 1024)
+                         (if (> buffer-length max-buffer)
+                             (error "Exceeded max-buffer of ~d" max-buffer)))
+                       (error "Unexpected errno ~d" errno))))))))
+    #-(and sb-thread os-provides-getprotoby-r)
+    (tagbody
+       (flet ((get-it ()
+                (let ((ent (sockint::getprotobyname name)))
+                  (if (sb-alien::null-alien ent)
+                      (go :error)
+                      (return-from get-protocol-by-name (protoent-to-values ent))))))
+         #+sb-thread
+         (sb-thread::with-system-mutex (**getprotoby-lock**)
+           (get-it))
+         #-sb-thread
+         (get-it))
+     :error
+       (error 'unknown-protocol :name name))))
 
 ;;; our protocol provides make-sockaddr-for, size-of-sockaddr,
 ;;; bits-of-sockaddr