From e99c4b816ad53c36e72edceaee5c8498fa331a31 Mon Sep 17 00:00:00 2001
From: Thomas Bernard <miniupnp@free.fr>
Date: Sat, 14 Mar 2020 00:10:29 +0100
Subject: [PATCH] tif_win32.c: do not _tiffMapProc() 0 sized files

see #22
---
 libtiff/tif_win32.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/libtiff/tif_win32.c b/libtiff/tif_win32.c
index bf5fbfb3..b3110b23 100644
--- a/libtiff/tif_win32.c
+++ b/libtiff/tif_win32.c
@@ -156,8 +156,10 @@ static uint64
 _tiffSizeProc(thandle_t fd)
 {
 	ULARGE_INTEGER m;
-	m.LowPart=GetFileSize(fd,&m.HighPart);
-	return(m.QuadPart);
+	if (GetFileSizeEx(fd,&m))
+		return(m.QuadPart);
+	else
+		return(0);
 }
 
 static int
@@ -189,7 +191,7 @@ _tiffMapProc(thandle_t fd, void** pbase, toff_t* psize)
 
 	size = _tiffSizeProc(fd);
 	sizem = (tmsize_t)size;
-	if ((uint64)sizem!=size)
+	if (!size || (uint64)sizem!=size)
 		return (0);
 
 	/* By passing in 0 for the maximum file size, it specifies that we