[src/trunk]: src/usr.sbin/dhcp/common For BPF, we must loop on receive_packet...

[mycroft <mycroft%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/5ca873887722
branches:  trunk
changeset: 499721:5ca873887722
user:      mycroft <mycroft%NetBSD.org@localhost>
date:      Mon Nov 27 17:33:02 2000 +0000

description:
For BPF, we must loop on receive_packet().  BPF may return multiple packets at
once, and we obviously won't get a select() hit for each one in that case.

diffstat:

 usr.sbin/dhcp/common/discover.c |  50 +++++++++++++++++++++++-----------------
 1 files changed, 29 insertions(+), 21 deletions(-)

diffs (78 lines):

diff -r 3c61848efda7 -r 5ca873887722 usr.sbin/dhcp/common/discover.c
--- a/usr.sbin/dhcp/common/discover.c   Mon Nov 27 17:25:24 2000 +0000
+++ b/usr.sbin/dhcp/common/discover.c   Mon Nov 27 17:33:02 2000 +0000
@@ -43,7 +43,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: discover.c,v 1.8 2000/10/17 16:10:42 taca Exp $ Copyright (c) 1995-2000 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: discover.c,v 1.9 2000/11/27 17:33:02 mycroft Exp $ Copyright (c) 1995-2000 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -669,6 +669,7 @@
        struct sockaddr_in from;
        struct hardware hfrom;
        struct iaddr ifrom;
+       isc_result_t status;
        int result;
        union {
                unsigned char packbuf [4095]; /* Packet input buffer.
@@ -682,30 +683,37 @@
                return ISC_R_INVALIDARG;
        ip = (struct interface_info *)h;
 
-       if ((result =
-            receive_packet (ip, u.packbuf, sizeof u, &from, &hfrom)) < 0) {
-               log_error ("receive_packet failed on %s: %m", ip -> name);
-               return ISC_R_UNEXPECTED;
-       }
-       if (result == 0)
-               return ISC_R_UNEXPECTED;
+       for (status = ISC_R_UNEXPECTED; ; status = ISC_R_SUCCESS) {
+               if ((result = receive_packet (ip, u.packbuf, sizeof u, &from,
+                   &hfrom)) < 0) {
+                       if (errno != EWOULDBLOCK) {
+                               log_error ("receive_packet failed on %s: %m",
+                                   ip -> name);
+                               return ISC_R_UNEXPECTED;
+                       } else
+                               return status;
+               }
+               if (result == 0)
+                       return status;
 
-       /* If we didn't at least get the fixed portion of the BOOTP
-          packet, drop the packet.  We're allowing packets with no
-          sname or filename, because we're aware of at least one
-          client that sends such packets, but this definitely falls
-          into the category of being forgiving. */
-       if (result < DHCP_FIXED_NON_UDP - DHCP_SNAME_LEN - DHCP_FILE_LEN)
-               return ISC_R_UNEXPECTED;
+               /* If we didn't at least get the fixed portion of the BOOTP
+                  packet, drop the packet.  We're allowing packets with no
+                  sname or filename, because we're aware of at least one
+                  client that sends such packets, but this definitely falls
+                  into the category of being forgiving. */
+               if (result <
+                   DHCP_FIXED_NON_UDP - DHCP_SNAME_LEN - DHCP_FILE_LEN)
+                       return ISC_R_UNEXPECTED;
 
-       if (bootp_packet_handler) {
-               ifrom.len = 4;
-               memcpy (ifrom.iabuf, &from.sin_addr, ifrom.len);
+               if (bootp_packet_handler) {
+                       ifrom.len = 4;
+                       memcpy (ifrom.iabuf, &from.sin_addr, ifrom.len);
 
-               (*bootp_packet_handler) (ip, &u.packet, (unsigned)result,
-                                        from.sin_port, ifrom, &hfrom);
+                       (*bootp_packet_handler) (ip, &u.packet,
+                                                (unsigned)result,
+                                                from.sin_port, ifrom, &hfrom);
+               }
        }
-       return ISC_R_SUCCESS;
 }
 
 isc_result_t interface_set_value (omapi_object_t *h,