X-Git-Url: https://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fftruncate.m4;h=4f2dafbab4c6939ba4cbd905a3d0aa1a2ed3c415;hb=da8054d48dc22e1c051db54049e005d51a006e69;hp=42730907a66115906022a6123ebeebcca8202ac8;hpb=d8710037842f70e32a5b56c685437b51165d2f5b;p=gnulib.git

diff --git a/m4/ftruncate.m4 b/m4/ftruncate.m4
index 42730907a..4f2dafbab 100644
--- a/m4/ftruncate.m4
+++ b/m4/ftruncate.m4
@@ -1,8 +1,8 @@
-# serial 17
+# serial 20
 
 # See if we need to emulate a missing ftruncate function using chsize.
 
-# Copyright (C) 2000-2001, 2003-2007, 2009-2011 Free Software Foundation, Inc.
+# Copyright (C) 2000-2001, 2003-2007, 2009-2013 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
@@ -11,7 +11,24 @@ AC_DEFUN([gl_FUNC_FTRUNCATE],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
   AC_CHECK_FUNCS_ONCE([ftruncate])
-  if test $ac_cv_func_ftruncate = no; then
+  if test $ac_cv_func_ftruncate = yes; then
+    m4_ifdef([gl_LARGEFILE], [
+      AC_REQUIRE([AC_CANONICAL_HOST])
+      case "$host_os" in
+        mingw*)
+          dnl Native Windows, and Large File Support is requested.
+          dnl The MSVCRT _chsize() function only accepts a 32-bit file size,
+          dnl and the mingw64 ftruncate64() function is unreliable (it may
+          dnl delete the file, see
+          dnl <http://mingw-w64.sourcearchive.com/documentation/2.0-1/ftruncate64_8c_source.html>).
+          dnl Use gnulib's ftruncate() implementation instead.
+          REPLACE_FTRUNCATE=1
+          ;;
+      esac
+    ], [
+      :
+    ])
+  else
     HAVE_FTRUNCATE=0
   fi
 ])