From ab6b4fdbded98ca6d185409e3c419ab1bfb26422 Mon Sep 17 00:00:00 2001
From: Jeremy Harris <jgh146exb@wizmail.org>
Date: Sat, 7 Dec 2019 22:07:02 +0000
Subject: [PATCH] FreeBSD: fix sendfile shim

---
 doc/doc-txt/ChangeLog |  4 ++++
 src/OS/Makefile-Base  | 28 ++++------------------------
 src/OS/os.c-FreeBSD   | 12 +++++++-----
 3 files changed, 15 insertions(+), 29 deletions(-)

diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index a8cd823b5..9f18a2073 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -218,6 +218,10 @@ JH/43 Bug 2465: Fix taint-handling in dsearch lookup.  Previously a nontainted
       buffer was used for the filename, resulting in a trap when tainted
       arguments (eg. $domain) were used.
 
+JH/46 FreeBSD: fix use of the sendfile() syscall.  The shim was not updating
+      the file-offset (which the Linux syscall does, and exim expects); this
+      resulted in an indefinite loop.
+
 
 Exim version 4.92
 -----------------
diff --git a/src/OS/Makefile-Base b/src/OS/Makefile-Base
index 9ecde1d3e..36af8308d 100644
--- a/src/OS/Makefile-Base
+++ b/src/OS/Makefile-Base
@@ -79,23 +79,8 @@ Makefile: ../OS/Makefile-Base ../OS/Makefile-Default \
 
 # Build (link) the os.h file
 
-#os.h:	$(SCRIPTS)/Configure-os.h \
-#	$(O)/os.h-AIX		$(O)/os.h-BSDI	$(O)/os.h-cygwin \
-#	$(O)/os.h-Darwin	$(O)/os.h-DGUX	$(O)/os.h-DragonFly \
-#	$(O)/os.h-FreeBSD	$(O)/os.h-GNU	$(O)/os.h-GNUkFreeBSD \
-#	$(O)/os.h-GNUkNetBSD	$(O)/os.h-HI-OSF \
-#	$(O)/os.h-HI-UX		$(O)/os.h-HP-UX	$(O)/os.h-HP-UX-9 \
-#	$(O)/os.h-IRIX		$(O)/os.h-IRIX6	$(O)/os.h-IRIX632 \
-#	$(O)/os.h-IRIX65	$(O)/os.h-Linux	$(O)/os.h-mips \
-#	$(O)/os.h-NetBSD	$(O)/os.h-NetBSD-a.out \
-#	$(O)/os.h-OpenBSD	$(O)/os.h-OpenUNIX	$(O)/os.h-OSF1 \
-#	$(O)/os.h-QNX		$(O)/os.h-SCO		$(O)/os.h-SCO_SV \
-#	$(O)/os.h-SunOS4	$(O)/os.h-SunOS5	$(O)/os.h-SunOS5-hal \
-#	$(O)/os.h-ULTRIX	$(O)/os.h-UNIX_SV \
-#	$(O)/os.h-Unixware7	$(O)/os.h-USG
-#	$(SHELL) $(SCRIPTS)/Configure-os.h
-
 os.h:	$(SCRIPTS)/Configure-os.h \
+	$(O)/os.h-Darwin	\
 	$(O)/os.h-FreeBSD	\
 	$(O)/os.h-GNU		\
 	$(O)/os.h-Linux		\
@@ -105,17 +90,12 @@ os.h:	$(SCRIPTS)/Configure-os.h \
 
 # Build the os.c file
 
-#os.c:   ../src/os.c \
-#	$(SCRIPTS)/Configure-os.c \
-#	$(O)/os.c-cygwin	$(O)/os.c-GNU	$(O)/os.c-HI-OSF \
-#	$(O)/os.c-IRIX		$(O)/os.c-IRIX6	$(O)/os.c-IRIX632 \
-#	$(O)/os.c-IRIX65	$(O)/os.c-Linux	$(O)/os.c-OSF1
-#	$(SHELL) $(SCRIPTS)/Configure-os.c
-
 os.c:   ../src/os.c \
 	$(SCRIPTS)/Configure-os.c \
+	$(O)/os.c-FreeBSD	\
 	$(O)/os.c-GNU		\
-	$(O)/os.c-Linux
+	$(O)/os.c-Linux		\
+	$(O)/os.c-SunOS5
 	$(SHELL) $(SCRIPTS)/Configure-os.c
 
 # Build the config.h file.
diff --git a/src/OS/os.c-FreeBSD b/src/OS/os.c-FreeBSD
index 1261b8557..4cc46c752 100644
--- a/src/OS/os.c-FreeBSD
+++ b/src/OS/os.c-FreeBSD
@@ -2,7 +2,7 @@
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) Jeremy Harris 1995 - 2018 */
+/* Copyright (c) Jeremy Harris 1995 - 2019 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 /* FreeBSD-specific code. This is concatenated onto the generic
@@ -14,11 +14,13 @@ src/os.c file. */
 *************/
 
 ssize_t
-os_sendfile(int out, int in, off_t * off, size_t cnt)
+os_sendfile(int out, int in, off_t * offp, size_t cnt)
 {
-off_t written;
-return sendfile(in, out, *off, cnt, NULL, &written, 0) < 0
-  ? (ssize_t) -1 : (ssize_t) written;
+off_t loff = *offp, written;
+
+if (sendfile(in, out, loff, cnt, NULL, &written, 0) < 0) return (ssize_t)-1;
+*offp = loff + written;
+return (ssize_t)written;
 }
 
 /* End of os.c-Linux */
-- 
2.30.2