Add MSG_PEEK support to pflocal

* libpipe/pq.h (packet_peek): Declare new function.
* libpipe/pq.c (packet_read): Move code to new `packet_fetch' function, call it
with `remove' set to 1.
(packet_fetch): New function with code from `packet_read', but do not remove
data if `remove' is 0.
(packet_peek): New function, calls `packet_fetch' with `remove' set to 0.
* libpipe/dgram.c (dgram_read): When MSG_PEEK is in *flags, do not dequeue
and only peek data.
* libpipe/seqpack.c (seqpack_read): Likewise.
* libpipe/stream.c (stream_read): Likewise.
* pflocal/socket.c (S_socket_recv): Pass MSG_PEEK flag to libpipe.

1 files changed, 10 insertions, 2 deletions

diff --git a/libpipe/dgram.c b/libpipe/dgram.c
index 3f3b2ab6..30695f1e 100644
--- a/libpipe/dgram.c
+++ b/libpipe/dgram.c
@@ -40,8 +40,16 @@ static error_t
 dgram_read (struct packet *packet, int *dequeue, unsigned *flags,
 	    char **data, size_t *data_len, size_t amount)
 {
-  *dequeue = 1;
-  return packet_read (packet, data, data_len, amount);
+  if (flags && *flags & MSG_PEEK)
+    {
+      *dequeue = 0;
+      return packet_peek (packet, data, data_len, amount);
+    }
+  else
+    {
+      *dequeue = 1;
+      return packet_read (packet, data, data_len, amount);
+    }
 }
 
 struct pipe_class _dgram_pipe_class =