From 934266ca4b894d37c3ade52d1e50576c33e2b40e Mon Sep 17 00:00:00 2001
From: Szymon Walter <walter.szymon.98@gmail.com>
Date: Wed, 21 Mar 2018 18:54:50 +0100
Subject: [PATCH] add constraints to `Size` trait

---
 src/fs.rs              | 14 ++++++--------
 src/lib.rs             |  1 +
 src/sector.rs          |  4 ++--
 src/sys/block_group.rs | 10 ++--------
 src/sys/inode.rs       |  5 +----
 src/sys/superblock.rs  |  2 +-
 src/volume/mod.rs      |  4 ++--
 7 files changed, 15 insertions(+), 25 deletions(-)

diff --git a/src/fs.rs b/src/fs.rs
index 385765a..be333db 100644
--- a/src/fs.rs
+++ b/src/fs.rs
@@ -30,7 +30,7 @@ pub struct Ext2<S: Size, V: Volume<u8, Address<S>>> {
     block_groups: Struct<Vec<BlockGroupDescriptor>, S>,
 }
 
-impl<S: Size + Copy, V: Volume<u8, Address<S>>> Ext2<S, V>
+impl<S: Size, V: Volume<u8, Address<S>>> Ext2<S, V>
 where
     Error: From<V::Error>,
 {
@@ -145,7 +145,7 @@ where
     }
 }
 
-impl<S: Size + Copy, V: Volume<u8, Address<S>>> Ext2<S, V> {
+impl<S: Size, V: Volume<u8, Address<S>>> Ext2<S, V> {
     fn superblock(&self) -> &Superblock {
         &self.superblock.inner
     }
@@ -224,8 +224,7 @@ pub struct Inodes<'a, S: 'a + Size, V: 'a + Volume<u8, Address<S>>> {
     index: usize,
 }
 
-impl<'a, S: Size + Copy, V: 'a + Volume<u8, Address<S>>> Iterator
-    for Inodes<'a, S, V>
+impl<'a, S: Size, V: 'a + Volume<u8, Address<S>>> Iterator for Inodes<'a, S, V>
 where
     Error: From<V::Error>,
 {
@@ -261,7 +260,7 @@ pub struct Inode<'a, S: 'a + Size, V: 'a + Volume<u8, Address<S>>> {
     inner: RawInode,
 }
 
-impl<'a, S: 'a + Size + Copy, V: 'a + Volume<u8, Address<S>>> Inode<'a, S, V> {
+impl<'a, S: 'a + Size, V: 'a + Volume<u8, Address<S>>> Inode<'a, S, V> {
     pub fn new(fs: &'a Ext2<S, V>, inner: RawInode) -> Inode<'a, S, V> {
         Inode { fs, inner }
     }
@@ -345,8 +344,7 @@ pub struct InodeBlocks<'a: 'b, 'b, S: 'a + Size, V: 'a + Volume<u8, Address<S>>>
     index: usize,
 }
 
-impl<'a, 'b, S: Size + Copy, V: 'a + Volume<u8, Address<S>>>
-    InodeBlocks<'a, 'b, S, V>
+impl<'a, 'b, S: Size, V: 'a + Volume<u8, Address<S>>> InodeBlocks<'a, 'b, S, V>
 where
     Error: From<V::Error>,
 {
@@ -355,7 +353,7 @@ where
     }
 }
 
-impl<'a, 'b, S: Size + Copy, V: 'a + Volume<u8, Address<S>>> Iterator
+impl<'a, 'b, S: Size, V: 'a + Volume<u8, Address<S>>> Iterator
     for InodeBlocks<'a, 'b, S, V>
 where
     Error: From<V::Error>,
diff --git a/src/lib.rs b/src/lib.rs
index 59a6381..1e36af7 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -13,6 +13,7 @@ extern crate alloc;
 extern crate bitflags;
 #[cfg(any(test, not(feature = "no_std")))]
 extern crate core;
+extern crate spin;
 
 pub mod error;
 pub mod sys;
diff --git a/src/sector.rs b/src/sector.rs
index de229fd..2d24b02 100644
--- a/src/sector.rs
+++ b/src/sector.rs
@@ -4,7 +4,7 @@ use core::ops::{Add, Sub};
 use core::fmt::{self, Debug, Display, LowerHex};
 use core::iter::Step;
 
-pub trait Size: PartialOrd {
+pub trait Size: Clone + Copy + PartialOrd {
     // log_sector_size = log_2(sector_size)
     const LOG_SIZE: u32;
     const SIZE: usize = 1 << Self::LOG_SIZE;
@@ -96,7 +96,7 @@ impl<S: Size> Address<S> {
     }
 }
 
-impl<S: Size + Clone + PartialOrd> Step for Address<S> {
+impl<S: Size> Step for Address<S> {
     fn steps_between(start: &Self, end: &Self) -> Option<usize> {
         if end.sector >= start.sector {
             Some(end.sector as usize - start.sector as usize)
diff --git a/src/sys/block_group.rs b/src/sys/block_group.rs
index 5a713d8..b280aeb 100644
--- a/src/sys/block_group.rs
+++ b/src/sys/block_group.rs
@@ -52,10 +52,7 @@ impl Debug for BlockGroupDescriptor {
 }
 
 impl BlockGroupDescriptor {
-    pub unsafe fn find_descriptor<
-        S: Size + Copy + PartialOrd,
-        V: Volume<u8, Address<S>>,
-    >(
+    pub unsafe fn find_descriptor<S: Size, V: Volume<u8, Address<S>>>(
         haystack: &V,
         offset: Address<S>,
     ) -> Result<(BlockGroupDescriptor, Address<S>), Error>
@@ -79,10 +76,7 @@ impl BlockGroupDescriptor {
         Ok(descr)
     }
 
-    pub unsafe fn find_descriptor_table<
-        S: Size + Copy + PartialOrd,
-        V: Volume<u8, Address<S>>,
-    >(
+    pub unsafe fn find_descriptor_table<S: Size, V: Volume<u8, Address<S>>>(
         haystack: &V,
         offset: Address<S>,
         count: usize,
diff --git a/src/sys/inode.rs b/src/sys/inode.rs
index a969fef..f391cbf 100644
--- a/src/sys/inode.rs
+++ b/src/sys/inode.rs
@@ -97,10 +97,7 @@ impl Debug for Inode {
 }
 
 impl Inode {
-    pub unsafe fn find_inode<
-        S: Size + Copy + PartialOrd,
-        V: Volume<u8, Address<S>>,
-    >(
+    pub unsafe fn find_inode<S: Size, V: Volume<u8, Address<S>>>(
         haystack: &V,
         offset: Address<S>,
         size: usize,
diff --git a/src/sys/superblock.rs b/src/sys/superblock.rs
index 2ad9cc6..917d705 100644
--- a/src/sys/superblock.rs
+++ b/src/sys/superblock.rs
@@ -195,7 +195,7 @@ impl Debug for Superblock {
 }
 
 impl Superblock {
-    pub unsafe fn find<S: Size + Copy + PartialOrd, V: Volume<u8, Address<S>>>(
+    pub unsafe fn find<S: Size, V: Volume<u8, Address<S>>>(
         haystack: &V,
     ) -> Result<(Superblock, Address<S>), Error>
     where
diff --git a/src/volume/mod.rs b/src/volume/mod.rs
index 054dd37..fa427b0 100644
--- a/src/volume/mod.rs
+++ b/src/volume/mod.rs
@@ -227,7 +227,7 @@ impl<T, Idx> DerefMut for VolumeCommit<T, Idx> {
 
 macro_rules! impl_slice {
     (@inner $volume:ty $( , $lt:lifetime )* ) => {
-        impl<$( $lt, )* S: Size + PartialOrd + Copy, T> Volume<T, Address<S>>
+        impl<$( $lt, )* S: Size, T> Volume<T, Address<S>>
             for $volume
         where
             T: Clone,
@@ -295,7 +295,7 @@ mod file {
     use super::{Volume, VolumeCommit, VolumeSlice};
     use super::length::Length;
 
-    impl<S: Size + PartialOrd + Copy> Volume<u8, Address<S>> for RefCell<File> {
+    impl<S: Size> Volume<u8, Address<S>> for RefCell<File> {
         type Error = io::Error;
 
         fn size(&self) -> Length<Address<S>> {