[master] 81cc3b3be Use VTCP_Assert() in VTCP_read()

[Martin Blix Grydeland]

commit 81cc3b3be05a735e8d572a0e9cb08f521979f2b7
Author: Martin Blix Grydeland <martin at varnish-software.com>
Date:   Wed Oct 7 16:04:21 2020 +0200

    Use VTCP_Assert() in VTCP_read()

diff --git a/lib/libvarnish/vtcp.c b/lib/libvarnish/vtcp.c
index 851e3137e..1cf21b0a1 100644
--- a/lib/libvarnish/vtcp.c
+++ b/lib/libvarnish/vtcp.c
@@ -619,5 +619,6 @@ VTCP_read(int fd, void *ptr, size_t len, vtim_dur tmo)
 			return (-2);
 	}
 	i = read(fd, ptr, len);
+	VTCP_Assert(i);
 	return (i < 0 ? -1 : i);
 }