From dc3de618edc343f0ceb74df9db55492e12624f23 Mon Sep 17 00:00:00 2001
From: Dietmar Maurer <dietmar@proxmox.com>
Date: Thu, 27 Dec 2018 09:20:17 +0100
Subject: [PATCH] new helper map_struct and map_struct_mut

---
 src/tools.rs | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/tools.rs b/src/tools.rs
index 30a8b190..6c22a62c 100644
--- a/src/tools.rs
+++ b/src/tools.rs
@@ -13,6 +13,21 @@ use std::os::unix::io::AsRawFd;
 
 pub mod timer;
 
+fn map_struct<T>(buffer: &[u8]) -> Result<&T, Error> {
+    if buffer.len() < ::std::mem::size_of::<T>() {
+        bail!("unable to map struct - buffer too small");
+    }
+    return Ok(unsafe { & * (buffer.as_ptr() as *const T) });
+}
+
+fn map_struct_mut<T>(buffer: &mut [u8]) -> Result<&mut T, Error> {
+    if buffer.len() < ::std::mem::size_of::<T>() {
+        bail!("unable to map struct - buffer too small");
+    }
+    return Ok(unsafe { &mut * (buffer.as_ptr() as *mut T) });
+}
+
+
 pub fn file_set_contents<P: AsRef<Path>>(
     path: P,
     data: &[u8],