xnu-2782.20.48.tar.gz

[apple/xnu.git] / bsd / kern / uipc_socket.c

diff --git a/bsd/kern/uipc_socket.c b/bsd/kern/uipc_socket.c
index 6b57b3cf8733da668789a871b9f52f41dafc6f3f..2dc33d759b411b7d92e1acb88711bd0e45d82eae 100644 (file)
--- a/bsd/kern/uipc_socket.c
+++ b/bsd/kern/uipc_socket.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998-2014 Apple Inc. All rights reserved.
+ * Copyright (c) 1998-2015 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
@@ -5392,6 +5392,17 @@ soo_kqfilter(struct fileproc *fp, struct knote *kn, vfs_context_t ctx)
        switch (kn->kn_filter) {
        case EVFILT_READ:
                kn->kn_fop = &soread_filtops;
+               /*
+                * If the caller explicitly asked for OOB results (e.g. poll()),
+                * save that off in the hookid field and reserve the kn_flags
+                * EV_OOBAND bit for output only).
+                */
+               if (kn->kn_flags & EV_OOBAND) {
+                       kn->kn_flags &= ~EV_OOBAND;
+                       kn->kn_hookid = EV_OOBAND;
+               } else {
+                       kn->kn_hookid = 0;
+               }
                skl = &so->so_rcv.sb_sel.si_note;
                break;
        case EVFILT_WRITE:
@@ -5467,44 +5478,42 @@ filt_soread(struct knote *kn, long hint)
        }
 
        /* socket isn't a listener */
-
        kn->kn_data = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
+       /*
+        * Clear out EV_OOBAND that filt_soread may have set in the
+        * past.
+        */
+       kn->kn_flags &= ~EV_OOBAND;
 
-       if (so->so_oobmark) {
-               if (kn->kn_flags & EV_OOBAND) {
+       if ((so->so_oobmark) || (so->so_state & SS_RCVATMARK)){
+               kn->kn_flags |= EV_OOBAND;
+               /*
+                * If caller registered explicit interest in OOB data,
+                * return immediately (data == amount beyond mark, for
+                * legacy reasons - that should be changed later).
+                */
+               if (kn->kn_hookid == EV_OOBAND) {
+                       /*
+                        * When so_state is SS_RCVATMARK, so_oobmark
+                        * is 0.
+                        */
                        kn->kn_data -= so->so_oobmark;
                        if ((hint & SO_FILT_HINT_LOCKED) == 0)
                                socket_unlock(so, 1);
                        return (1);
                }
-               kn->kn_data = so->so_oobmark;
-               kn->kn_flags |= EV_OOBAND;
-       } else {
-               if ((so->so_state & SS_CANTRCVMORE)
+       }
+       
+       if ((so->so_state & SS_CANTRCVMORE)
 #if CONTENT_FILTER
-               && cfil_sock_data_pending(&so->so_rcv) == 0
+           && cfil_sock_data_pending(&so->so_rcv) == 0
 #endif /* CONTENT_FILTER */
-               ) {
-                       kn->kn_flags |= EV_EOF;
-                       kn->kn_fflags = so->so_error;
-                       if ((hint & SO_FILT_HINT_LOCKED) == 0)
-                               socket_unlock(so, 1);
-                       return (1);
-               }
-       }
-
-       if (so->so_state & SS_RCVATMARK) {
-               if (kn->kn_flags & EV_OOBAND) {
-                       if ((hint & SO_FILT_HINT_LOCKED) == 0)
-                               socket_unlock(so, 1);
-                       return (1);
-               }
-               kn->kn_flags |= EV_OOBAND;
-       } else if (kn->kn_flags & EV_OOBAND) {
-               kn->kn_data = 0;
+          ) {
+               kn->kn_flags |= EV_EOF;
+               kn->kn_fflags = so->so_error;
                if ((hint & SO_FILT_HINT_LOCKED) == 0)
                        socket_unlock(so, 1);
-               return (0);
+               return (1);
        }
 
        if (so->so_error) {     /* temporary udp error */
@@ -5524,7 +5533,7 @@ filt_soread(struct knote *kn, long hint)
        if ((hint & SO_FILT_HINT_LOCKED) == 0)
                socket_unlock(so, 1);
 
-       return ((kn->kn_flags & EV_OOBAND) || kn->kn_data >= lowwat);
+       return (kn->kn_data >= lowwat);
 }
 
 static void