[PATCH hurd v2] pfinet: implement rudimentary SO_TIMESTAMP support

[dnietoc]

From: Diego Nieto Cid <dnie...@gmail.com>

This patch adds support for UDP packet timestamping only when
both SO_TIMESTAMP and SCM_TIMESTAMP are defined.

* pfinet/linux-src/include/net/sock.h: add timestamp flag

* pfinet/linux-src/net/core/sock.c: modify sock_*sockopt to set
  and query the timestamp flag.

* pfinet/linux-src/net/ipv4/udp.c: call put_cmsg in udp_recvmsg
  to write the packet timestamp to the message anciliary data.
---
 pfinet/linux-src/include/net/sock.h |  3 +++
 pfinet/linux-src/net/core/sock.c    | 10 ++++++++++
 pfinet/linux-src/net/ipv4/udp.c     |  5 +++++
 3 files changed, 18 insertions(+)

diff --git a/pfinet/linux-src/include/net/sock.h 
b/pfinet/linux-src/include/net/sock.h
index 5c4444d1..435f8870 100644
--- a/pfinet/linux-src/include/net/sock.h
+++ b/pfinet/linux-src/include/net/sock.h
@@ -411,6 +411,9 @@ struct sock {
                                broadcast,
                                bsdism;
        unsigned char           debug;
+#if defined(SO_TIMESTAMP) && defined(SCM_TIMESTAMP)
+       unsigned char           timestamp;
+#endif
        int                     proc;
        unsigned long           lingertime;
 
diff --git a/pfinet/linux-src/net/core/sock.c b/pfinet/linux-src/net/core/sock.c
index c47c935b..5ab7d840 100644
--- a/pfinet/linux-src/net/core/sock.c
+++ b/pfinet/linux-src/net/core/sock.c
@@ -191,6 +191,11 @@ int sock_setsockopt(struct socket *sock, int level, int 
optname,
                        else
                                sk->debug=valbool;
                        break;
+#if defined(SO_TIMESTAMP) && defined(SCM_TIMESTAMP)
+               case SO_TIMESTAMP:
+                       sk->timestamp = valbool;
+                       break;
+#endif
                case SO_REUSEADDR:
                        sk->reuse = valbool;
                        break;
@@ -384,6 +389,11 @@ int sock_getsockopt(struct socket *sock, int level, int 
optname,
                case SO_DEBUG:          
                        v.val = sk->debug;
                        break;
+#if defined(SO_TIMESTAMP) && defined(SCM_TIMESTAMP)
+               case SO_TIMESTAMP:
+                       v.val = sk->timestamp;
+                       break;
+#endif
                
                case SO_DONTROUTE:
                        v.val = sk->localroute;
diff --git a/pfinet/linux-src/net/ipv4/udp.c b/pfinet/linux-src/net/ipv4/udp.c
index c1da9886..52bae18e 100644
--- a/pfinet/linux-src/net/ipv4/udp.c
+++ b/pfinet/linux-src/net/ipv4/udp.c
@@ -813,6 +813,11 @@ int udp_recvmsg(struct sock *sk, struct msghdr *msg, int 
len,
                msg->msg_flags |= MSG_TRUNC;
        }
 
+#if defined(SO_TIMESTAMP) && defined(SCM_TIMESTAMP)
+       if (sk->timestamp)
+               put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP, sizeof(skb->stamp), 
&skb->stamp);
+#endif
+
 #ifndef CONFIG_UDP_DELAY_CSUM
        err = skb_copy_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov,
                                        copied);
-- 
2.53.0