From 23531be27262f6065cdb46fa4c346b11a8b85a98 Mon Sep 17 00:00:00 2001
From: greatroar <@>
Date: Sat, 10 Apr 2021 16:54:07 +0200
Subject: [PATCH] Use FcntlFstore to preallocate on Mac

---
 internal/restorer/preallocate_darwin.go | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/internal/restorer/preallocate_darwin.go b/internal/restorer/preallocate_darwin.go
index 73de322dd..ae6e5ee3e 100644
--- a/internal/restorer/preallocate_darwin.go
+++ b/internal/restorer/preallocate_darwin.go
@@ -2,8 +2,6 @@ package restorer
 
 import (
 	"os"
-	"runtime"
-	"unsafe"
 
 	"golang.org/x/sys/unix"
 )
@@ -16,7 +14,7 @@ func preallocateFile(wr *os.File, size int64) error {
 		Offset:  0,
 		Length:  size,
 	}
-	_, err := unix.FcntlInt(wr.Fd(), unix.F_PREALLOCATE, int(uintptr(unsafe.Pointer(&fst))))
+	err := unix.FcntlFstore(wr.Fd(), unix.F_PREALLOCATE, &fst)
 
 	if err == nil {
 		return nil
@@ -24,10 +22,7 @@ func preallocateFile(wr *os.File, size int64) error {
 
 	// just take preallocation in any form, but still ask for everything
 	fst.Flags = unix.F_ALLOCATEALL
-	_, err = unix.FcntlInt(wr.Fd(), unix.F_PREALLOCATE, int(uintptr(unsafe.Pointer(&fst))))
-
-	// Keep struct alive until fcntl has returned
-	runtime.KeepAlive(fst)
+	err = unix.FcntlFstore(wr.Fd(), unix.F_PREALLOCATE, &fst)
 
 	return err
 }