From d077ea28e30e4240883df59cc93be994b0edf70c Mon Sep 17 00:00:00 2001
From: Giuseppe Scrivano <gscrivan@redhat.com>
Date: Mon, 18 Nov 2019 13:41:51 +0100
Subject: [PATCH] configure: check for FUSE copy_file_range

check if the version of FUSE supports copy_file_range.

It fixes the build on RHEL 8.

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
---
 configure.ac | 20 +++++++++++++++++++-
 main.c       |  2 +-
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/configure.ac b/configure.ac
index 789136d..f0d5525 100644
--- a/configure.ac
+++ b/configure.ac
@@ -49,10 +49,28 @@ void foo()
 ],
 [cache_readdir=1],
 [cache_readdir=0])
+
+
+AC_COMPILE_IFELSE(
+[
+AC_LANG_SOURCE([
+#define FUSE_USE_VERSION 32
+#include <fuse_lowlevel.h>
+void foo()
+{
+        struct fuse_lowlevel_ops ops;
+        ops.copy_file_range = 0;
+}])
+],
+[fuse_has_copy_file_range=1],
+[fuse_has_copy_file_range=0])
+
+
 CFLAGS=$old_CFLAGS
 LDFLAGS=$old_LDFLAGS
 
-AC_DEFINE_UNQUOTED([HAVE_FUSE_CACHE_READDIR], $cache_readdir, [Define if libfuse is available])
+AC_DEFINE_UNQUOTED([HAVE_FUSE_CACHE_READDIR], $cache_readdir, [Define if libfuse cache_readdir is available])
+AC_DEFINE_UNQUOTED([HAVE_FUSE_COPY_FILE_RANGE], $fuse_has_copy_file_range, [Define if libfuse has copy_file_range is available])
 
 AC_SEARCH_LIBS([dlopen], [dl], [], [AC_MSG_ERROR([unable to find dlopen()])])
 
diff --git a/main.c b/main.c
index fea2392..90e99b2 100644
--- a/main.c
+++ b/main.c
@@ -4887,7 +4887,7 @@ static struct fuse_lowlevel_ops ovl_oper =
    .fsyncdir = ovl_fsyncdir,
    .ioctl = ovl_ioctl,
    .fallocate = ovl_fallocate,
-#ifdef HAVE_COPY_FILE_RANGE
+#if HAVE_COPY_FILE_RANGE && HAVE_FUSE_COPY_FILE_RANGE
    .copy_file_range = ovl_copy_file_range,
 #endif
   };