From: Stefan Metzmacher <metze@samba.org>
Date: Mon, 8 Jun 2020 12:21:25 +0000 (+0200)
Subject: socket_wrapper.c: let swrap_vioctl() handle SIOCOUTQ/TIOCOUTQ/FIONWRITE explicitly
X-Git-Tag: socket_wrapper-1.2.5~1
X-Git-Url: http://git.samba.org/?p=socket_wrapper.git;a=commitdiff_plain;h=b94af548f42e561207db7cacbe09c9e3286de2d3

socket_wrapper.c: let swrap_vioctl() handle SIOCOUTQ/TIOCOUTQ/FIONWRITE explicitly

They are used to ask for the number of unacked bytes in the send queue,
with AF_UNIX sockets get strange result, on linux 5.3 I get more bytes
reported than I sent into the socket. All bytes reach the destination
directly, so we can just always report 0 unacked bytes.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=11897

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>
(cherry picked from commit f317ebcdcdd626ed9e06de2eb60031306994c803)
---

diff --git a/src/socket_wrapper.c b/src/socket_wrapper.c
index fe67285..ffdd31a 100644
--- a/src/socket_wrapper.c
+++ b/src/socket_wrapper.c
@@ -4751,6 +4751,24 @@ static int swrap_vioctl(int s, unsigned long int r, va_list va)
 			swrap_pcap_dump_packet(si, NULL, SWRAP_PENDING_RST, NULL, 0);
 		}
 		break;
+#ifdef FIONWRITE
+	case FIONWRITE:
+		/* this is FreeBSD */
+		FALL_THROUGH; /* to TIOCOUTQ */
+#endif /* FIONWRITE */
+	case TIOCOUTQ: /* same as SIOCOUTQ on Linux */
+		/*
+		 * This may return more bytes then the application
+		 * sent into the socket, for tcp it should
+		 * return the number of unacked bytes.
+		 *
+		 * On AF_UNIX, all bytes are immediately acked!
+		 */
+		if (rc == 0) {
+			value_ptr = ((int *)va_arg(ap, int *));
+			*value_ptr = 0;
+		}
+		break;
 	}
 
 	va_end(ap);