make `Buffer` generic over its index, instead of `usize`
Szymon Walter
parent
7e0af1b8f6
commit
7c57c047bc
78
src/block.rs
78
src/block.rs
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@ -4,39 +4,33 @@ use core::ops::{Add, Sub};
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use core::fmt::{self, Debug, Display, LowerHex};
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use core::iter::Step;
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pub trait Size {
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// log_block_size = log_2(block_size) - 10
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// i.e. block_size = 1024 << log_block_size
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pub trait Size: PartialOrd {
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// log_block_size = log_2(block_size)
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const LOG_SIZE: u32;
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const SIZE: usize = 1024 << Self::LOG_SIZE;
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const SIZE: usize = 1 << Self::LOG_SIZE;
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const OFFSET_MASK: usize = Self::SIZE - 1;
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}
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#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
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pub struct Size1024;
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impl Size for Size1024 {
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const LOG_SIZE: u32 = 0;
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#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
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pub struct Size512;
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impl Size for Size512 {
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const LOG_SIZE: u32 = 9;
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}
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#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
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#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
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pub struct Size2048;
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impl Size for Size2048 {
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const LOG_SIZE: u32 = 1;
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const LOG_SIZE: u32 = 11;
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}
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#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
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#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
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pub struct Size4096;
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impl Size for Size4096 {
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const LOG_SIZE: u32 = 2;
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const LOG_SIZE: u32 = 12;
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}
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#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
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pub struct Size8192;
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impl Size for Size8192 {
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const LOG_SIZE: u32 = 3;
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}
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#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
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/// Address in a physical sector
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#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
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pub struct Address<S: Size> {
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block: usize,
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offset: usize,
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@ -55,14 +49,30 @@ impl<S: Size> Address<S> {
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}
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pub fn new(block: usize, offset: isize) -> Address<S> {
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let block = (block as isize + (offset >> (S::LOG_SIZE + 10))) as usize;
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let block = (block as isize + (offset >> S::LOG_SIZE)) as usize;
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let offset = offset.abs() as usize & S::OFFSET_MASK;
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unsafe { Address::new_unchecked(block, offset) }
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}
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pub fn with_block_size(
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block: usize,
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offset: usize,
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log_block_size: u32,
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) -> Address<S> {
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let log_diff = log_block_size as isize - S::LOG_SIZE as isize;
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let top_offset = offset >> S::LOG_SIZE;
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let offset = offset >> log_diff;
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let block = block << log_diff | top_offset;
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Address::new(block, offset as isize)
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}
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pub fn index64(&self) -> u64 {
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((self.block as u64) << S::LOG_SIZE) + self.offset as u64
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}
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pub fn into_index(&self) -> Option<usize> {
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self.block
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.checked_shl(S::LOG_SIZE + 10)
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.checked_shl(S::LOG_SIZE)
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.and_then(|block| block.checked_add(self.offset))
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}
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@ -137,9 +147,17 @@ impl<S: Size> LowerHex for Address<S> {
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}
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}
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impl<S: Size> From<u64> for Address<S> {
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fn from(idx: u64) -> Address<S> {
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let block = idx >> S::LOG_SIZE;
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let offset = idx & S::OFFSET_MASK as u64;
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Address::new(block as usize, offset as isize)
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}
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}
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impl<S: Size> From<usize> for Address<S> {
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fn from(idx: usize) -> Address<S> {
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let block = idx >> (S::LOG_SIZE + 10);
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let block = idx >> S::LOG_SIZE;
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let offset = idx & S::OFFSET_MASK;
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Address::new(block, offset as isize)
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}
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@ -172,13 +190,13 @@ mod tests {
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#[test]
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fn arithmetic() {
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assert_eq!(
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Address::<Size1024>::new(0, 1024),
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Address::<Size1024>::new(1, 0),
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Address::<Size512>::new(0, 512),
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Address::<Size512>::new(1, 0),
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);
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assert_eq!(
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Address::<Size1024>::new(2, -512),
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Address::<Size1024>::new(1, 512),
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Address::<Size512>::new(2, -256),
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Address::<Size512>::new(1, 256),
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);
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let a = Address::<Size2048>::new(0, 1024);
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@ -186,9 +204,9 @@ mod tests {
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assert_eq!(a + b, Address::<Size2048>::new(1, 0));
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assert_eq!((a + b).into_index(), Some(2048));
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let a = Address::<Size1024>::new(0, 4096);
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let b = Address::<Size1024>::new(0, 512);
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assert_eq!(a - b, Address::<Size1024>::new(3, 512));
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assert_eq!((a - b).into_index(), Some(3584));
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let a = Address::<Size512>::new(0, 2048);
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let b = Address::<Size512>::new(0, 256);
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assert_eq!(a - b, Address::<Size512>::new(3, 256));
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assert_eq!((a - b).into_index(), Some(1792));
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}
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}
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@ -7,6 +7,7 @@ use alloc::boxed::Box;
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use alloc::borrow::{Cow, ToOwned};
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use error::Infallible;
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use block::{Address, Size};
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pub mod length;
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use self::length::Length;
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@ -21,14 +22,17 @@ where
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fn len(&self) -> Length<Idx>;
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fn commit(
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&mut self,
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slice: Option<BufferCommit<T>>,
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slice: Option<BufferCommit<T, Idx>>,
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) -> Result<(), Self::Error>;
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unsafe fn slice_unchecked<'a>(
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&'a self,
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range: Range<Idx>,
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) -> BufferSlice<'a, T>;
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) -> BufferSlice<'a, T, Idx>;
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fn slice<'a>(&'a self, range: Range<Idx>) -> Option<BufferSlice<'a, T>> {
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fn slice<'a>(
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&'a self,
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range: Range<Idx>,
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) -> Option<BufferSlice<'a, T, Idx>> {
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if self.len() >= range.end && self.len() > range.start {
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unsafe { Some(self.slice_unchecked(range)) }
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} else {
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@ -37,29 +41,34 @@ where
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}
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}
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pub struct BufferSlice<'a, T: 'a>
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pub struct BufferSlice<'a, T: 'a, Idx>
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where
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[T]: ToOwned,
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{
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inner: Cow<'a, [T]>,
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index: usize,
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index: Idx,
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}
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impl<T> BufferSlice<'static, T>
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impl<T, Idx: Default> BufferSlice<'static, T, Idx>
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where
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[T]: ToOwned,
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{
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pub fn with_static(inner: &'static [T]) -> BufferSlice<'static, T> {
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pub fn with_static(inner: &'static [T]) -> BufferSlice<'static, T, Idx> {
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BufferSlice {
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inner: Cow::Borrowed(inner),
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index: 0,
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index: Idx::default(),
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}
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}
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}
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impl<T, Idx> BufferSlice<'static, T, Idx>
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where
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[T]: ToOwned,
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{
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pub fn new_owned(
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inner: <[T] as ToOwned>::Owned,
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index: usize,
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) -> BufferSlice<'static, T> {
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index: Idx,
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) -> BufferSlice<'static, T, Idx> {
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BufferSlice {
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inner: Cow::Owned(inner),
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index,
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@ -67,11 +76,11 @@ where
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}
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}
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impl<'a, T> BufferSlice<'a, T>
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impl<'a, T, Idx> BufferSlice<'a, T, Idx>
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where
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[T]: ToOwned,
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{
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pub fn new(inner: &'a [T], index: usize) -> BufferSlice<'a, T> {
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pub fn new(inner: &'a [T], index: Idx) -> BufferSlice<'a, T, Idx> {
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BufferSlice {
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inner: Cow::Borrowed(inner),
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index,
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@ -85,14 +94,13 @@ where
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}
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}
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#[inline]
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pub fn at_index(&self) -> usize {
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self.index
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pub fn at_index(&self) -> &Idx {
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&self.index
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}
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}
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impl<'a> BufferSlice<'a, u8> {
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pub unsafe fn dynamic_cast<T: Copy>(&self) -> (T, usize) {
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impl<'a, Idx: Copy> BufferSlice<'a, u8, Idx> {
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pub unsafe fn dynamic_cast<T: Copy>(&self) -> (T, Idx) {
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assert!(self.inner.len() >= mem::size_of::<T>());
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let index = self.index;
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let cast = mem::transmute_copy(self.inner.as_ptr().as_ref().unwrap());
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@ -101,8 +109,8 @@ impl<'a> BufferSlice<'a, u8> {
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pub fn from_cast<T: Copy>(
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cast: &'a T,
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index: usize,
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) -> BufferSlice<'a, u8> {
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index: Idx,
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) -> BufferSlice<'a, u8, Idx> {
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let len = mem::size_of::<T>();
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let ptr = cast as *const T as *const u8;
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let slice = unsafe { slice::from_raw_parts(ptr, len) };
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@ -110,11 +118,11 @@ impl<'a> BufferSlice<'a, u8> {
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}
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}
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impl<'a, T> BufferSlice<'a, T>
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impl<'a, T, Idx> BufferSlice<'a, T, Idx>
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where
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[T]: ToOwned<Owned = Vec<T>>,
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{
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pub fn commit(self) -> Option<BufferCommit<T>> {
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pub fn commit(self) -> Option<BufferCommit<T, Idx>> {
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if self.is_mutated() {
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Some(BufferCommit::new(self.inner.into_owned(), self.index))
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} else {
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@ -123,7 +131,7 @@ where
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}
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}
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impl<'a, T> AsRef<[T]> for BufferSlice<'a, T>
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impl<'a, T, Idx> AsRef<[T]> for BufferSlice<'a, T, Idx>
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where
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[T]: ToOwned,
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{
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@ -132,7 +140,7 @@ where
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}
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}
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impl<'a, T> AsMut<[T]> for BufferSlice<'a, T>
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impl<'a, T, Idx> AsMut<[T]> for BufferSlice<'a, T, Idx>
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where
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[T]: ToOwned,
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<[T] as ToOwned>::Owned: AsMut<[T]>,
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@ -142,7 +150,7 @@ where
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}
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}
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impl<'a, T> Deref for BufferSlice<'a, T>
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impl<'a, T, Idx> Deref for BufferSlice<'a, T, Idx>
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where
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[T]: ToOwned,
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{
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@ -153,7 +161,7 @@ where
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}
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}
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impl<'a, T> DerefMut for BufferSlice<'a, T>
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impl<'a, T, Idx> DerefMut for BufferSlice<'a, T, Idx>
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where
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[T]: ToOwned,
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<[T] as ToOwned>::Owned: AsMut<[T]>,
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@ -163,17 +171,22 @@ where
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}
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}
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pub struct BufferCommit<T> {
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pub struct BufferCommit<T, Idx> {
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inner: Vec<T>,
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index: usize,
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index: Idx,
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}
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impl<T> BufferCommit<T> {
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pub fn with_vec(inner: Vec<T>) -> BufferCommit<T> {
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BufferCommit { inner, index: 0 }
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impl<T, Idx: Default> BufferCommit<T, Idx> {
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pub fn with_vec(inner: Vec<T>) -> BufferCommit<T, Idx> {
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BufferCommit {
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inner,
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index: Idx::default(),
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}
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}
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}
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pub fn new(inner: Vec<T>, index: usize) -> BufferCommit<T> {
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impl<T, Idx> BufferCommit<T, Idx> {
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pub fn new(inner: Vec<T>, index: Idx) -> BufferCommit<T, Idx> {
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BufferCommit { inner, index }
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}
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@ -181,25 +194,24 @@ impl<T> BufferCommit<T> {
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self.inner
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}
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#[inline]
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pub fn at_index(&self) -> usize {
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self.index
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pub fn at_index(&self) -> &Idx {
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&self.index
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}
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}
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impl<T> AsRef<[T]> for BufferCommit<T> {
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impl<T, Idx> AsRef<[T]> for BufferCommit<T, Idx> {
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fn as_ref(&self) -> &[T] {
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self.inner.as_ref()
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}
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}
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impl<T> AsMut<[T]> for BufferCommit<T> {
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impl<T, Idx> AsMut<[T]> for BufferCommit<T, Idx> {
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fn as_mut(&mut self) -> &mut [T] {
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self.inner.as_mut()
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}
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}
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impl<T> Deref for BufferCommit<T> {
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impl<T, Idx> Deref for BufferCommit<T, Idx> {
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type Target = [T];
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fn deref(&self) -> &Self::Target {
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@ -207,7 +219,7 @@ impl<T> Deref for BufferCommit<T> {
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}
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}
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impl<T> DerefMut for BufferCommit<T> {
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impl<T, Idx> DerefMut for BufferCommit<T, Idx> {
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fn deref_mut(&mut self) -> &mut Self::Target {
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self.as_mut()
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}
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@ -215,20 +227,20 @@ impl<T> DerefMut for BufferCommit<T> {
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macro_rules! impl_slice {
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(@inner $buffer:ty $( , $lt:lifetime )* ) => {
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impl<$( $lt, )* T> Buffer<T, usize> for $buffer
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impl<$( $lt, )* S: Size + PartialOrd + Copy, T> Buffer<T, Address<S>> for $buffer
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where
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T: Clone,
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[T]: ToOwned,
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{
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type Error = Infallible;
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fn len(&self) -> Length<usize> {
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Length::Bounded(<Self as AsRef<[T]>>::as_ref(self).len())
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fn len(&self) -> Length<Address<S>> {
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Length::Bounded(Address::from(<Self as AsRef<[T]>>::as_ref(self).len()))
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}
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fn commit(&mut self, slice: Option<BufferCommit<T>>) -> Result<(), Infallible> {
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fn commit(&mut self, slice: Option<BufferCommit<T, Address<S>>>) -> Result<(), Infallible> {
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slice.map(|slice| {
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let index = slice.at_index();
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let index = slice.at_index().index64() as usize;
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let end = index + slice.as_ref().len();
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// XXX: it would be much better to drop the contents of dst
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// and move the contents of slice instead of cloning
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@ -241,9 +253,10 @@ macro_rules! impl_slice {
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unsafe fn slice_unchecked<'a>(
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&'a self,
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range: Range<usize>,
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) -> BufferSlice<'a, T> {
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range: Range<Address<S>>,
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) -> BufferSlice<'a, T, Address<S>> {
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let index = range.start;
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let range = range.start.index64() as usize..range.end.index64() as usize;
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BufferSlice::new(
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<Self as AsRef<[T]>>::as_ref(self).get_unchecked(range),
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index,
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@ -270,33 +283,35 @@ mod file {
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use std::fs::File;
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use std::cell::RefCell;
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use block::{Address, Size};
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use super::{Buffer, BufferCommit, BufferSlice};
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use super::length::Length;
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impl Buffer<u8, usize> for RefCell<File> {
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impl<S: Size + PartialOrd + Copy> Buffer<u8, Address<S>> for RefCell<File> {
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type Error = io::Error;
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fn len(&self) -> Length<usize> {
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fn len(&self) -> Length<Address<S>> {
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Length::Bounded(
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self.borrow()
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.metadata()
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.map(|data| data.len() as usize)
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.unwrap_or(0),
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.map(|data| Address::from(data.len()))
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.unwrap_or(Address::from(0_usize)),
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)
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}
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fn commit(
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&mut self,
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slice: Option<BufferCommit<u8>>,
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slice: Option<BufferCommit<u8, Address<S>>>,
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) -> Result<(), Self::Error> {
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slice
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.map(|slice| {
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let index = slice.at_index();
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let end = index + slice.as_ref().len();
|
||||
let index = *slice.at_index();
|
||||
let end = index + Address::from(slice.as_ref().len());
|
||||
let mut refmut = self.borrow_mut();
|
||||
refmut
|
||||
.seek(SeekFrom::Start(index as u64))
|
||||
.and_then(|_| refmut.write(&slice.as_ref()[index..end]))
|
||||
.seek(SeekFrom::Start(index.index64()))
|
||||
.and_then(|_| refmut.write(slice.as_ref()))
|
||||
.map(|_| ())
|
||||
})
|
||||
.unwrap_or(Ok(()))
|
||||
|
|
@ -304,15 +319,15 @@ mod file {
|
|||
|
||||
unsafe fn slice_unchecked<'a>(
|
||||
&'a self,
|
||||
range: Range<usize>,
|
||||
) -> BufferSlice<'a, u8> {
|
||||
range: Range<Address<S>>,
|
||||
) -> BufferSlice<'a, u8, Address<S>> {
|
||||
let index = range.start;
|
||||
let len = range.end - range.start;
|
||||
let mut vec = Vec::with_capacity(len);
|
||||
vec.set_len(len);
|
||||
let mut vec = Vec::with_capacity(len.index64() as usize);
|
||||
vec.set_len(len.index64() as usize);
|
||||
let mut refmut = self.borrow_mut();
|
||||
refmut
|
||||
.seek(SeekFrom::Start(index as u64))
|
||||
.seek(SeekFrom::Start(index.index64()))
|
||||
.and_then(|_| refmut.read_exact(&mut vec[..]))
|
||||
.unwrap_or_else(|err| {
|
||||
panic!("could't read from File Buffer: {:?}", err)
|
||||
|
|
@ -322,14 +337,16 @@ mod file {
|
|||
|
||||
fn slice<'a>(
|
||||
&'a self,
|
||||
range: Range<usize>,
|
||||
) -> Option<BufferSlice<'a, u8>> {
|
||||
range: Range<Address<S>>,
|
||||
) -> Option<BufferSlice<'a, u8, Address<S>>> {
|
||||
let index = range.start;
|
||||
let mut vec = Vec::with_capacity(range.end - range.start);
|
||||
let mut vec = Vec::with_capacity(
|
||||
(range.end - range.start).index64() as usize,
|
||||
);
|
||||
let mut refmut = self.borrow_mut();
|
||||
refmut
|
||||
.seek(SeekFrom::Start(index as u64))
|
||||
.and_then(|_| refmut.read_exact(&mut vec[range]))
|
||||
.seek(SeekFrom::Start(index.index64()))
|
||||
.and_then(|_| refmut.read_exact(&mut vec[..]))
|
||||
.map(move |_| BufferSlice::new_owned(vec, index))
|
||||
.ok()
|
||||
}
|
||||
|
|
@ -338,13 +355,19 @@ mod file {
|
|||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use block::{Address, Size512};
|
||||
use super::*;
|
||||
|
||||
#[test]
|
||||
fn buffer() {
|
||||
let mut buffer = vec![0; 1024];
|
||||
let commit = {
|
||||
let mut slice = buffer.slice(256..512).unwrap();
|
||||
let mut slice = buffer
|
||||
.slice(
|
||||
Address::<Size512>::from(256_usize)
|
||||
..Address::<Size512>::from(512_usize),
|
||||
)
|
||||
.unwrap();
|
||||
slice.iter_mut().for_each(|x| *x = 1);
|
||||
slice.commit()
|
||||
};
|
||||
|
|
|
|||
|
|
@ -6,6 +6,7 @@ use std::io;
|
|||
pub enum Error {
|
||||
BadMagic(u16),
|
||||
OutOfBounds(usize),
|
||||
AddressOutOfBounds(usize, usize, usize),
|
||||
BadBlockGroupCount(u32, u32),
|
||||
#[cfg(any(test, not(feature = "no_std")))]
|
||||
Io(io::Error),
|
||||
|
|
|
|||
82
src/fs.rs
82
src/fs.rs
|
|
@ -1,41 +1,45 @@
|
|||
use core::mem;
|
||||
use core::marker::PhantomData;
|
||||
|
||||
use alloc::Vec;
|
||||
|
||||
use error::Error;
|
||||
use block::Address; // TODO
|
||||
use block::{Address, Size};
|
||||
use buffer::{Buffer, BufferSlice};
|
||||
use sys::superblock::Superblock;
|
||||
use sys::block_group::BlockGroupDescriptor;
|
||||
use sys::inode::Inode;
|
||||
|
||||
struct Struct<T> {
|
||||
struct Struct<T, S: Size> {
|
||||
pub inner: T,
|
||||
pub offset: usize,
|
||||
pub offset: Address<S>,
|
||||
}
|
||||
|
||||
impl<T> From<(T, usize)> for Struct<T> {
|
||||
impl<T, S: Size> From<(T, Address<S>)> for Struct<T, S> {
|
||||
#[inline]
|
||||
fn from((inner, offset): (T, usize)) -> Struct<T> {
|
||||
fn from((inner, offset): (T, Address<S>)) -> Struct<T, S> {
|
||||
Struct { inner, offset }
|
||||
}
|
||||
}
|
||||
|
||||
/// Safe wrapper for raw sys structs
|
||||
pub struct Ext2<B: Buffer<u8, usize>> {
|
||||
pub struct Ext2<S: Size, B: Buffer<u8, Address<S>>> {
|
||||
buffer: B,
|
||||
superblock: Struct<Superblock>,
|
||||
block_groups: Struct<Vec<BlockGroupDescriptor>>,
|
||||
superblock: Struct<Superblock, S>,
|
||||
block_groups: Struct<Vec<BlockGroupDescriptor>, S>,
|
||||
}
|
||||
|
||||
impl<B: Buffer<u8, usize>> Ext2<B>
|
||||
impl<S: Size + Copy, B: Buffer<u8, Address<S>>> Ext2<S, B>
|
||||
where
|
||||
Error: From<B::Error>,
|
||||
{
|
||||
pub fn new(buffer: B) -> Result<Ext2<B>, Error> {
|
||||
pub fn new(buffer: B) -> Result<Ext2<S, B>, Error> {
|
||||
let superblock = unsafe { Struct::from(Superblock::find(&buffer)?) };
|
||||
let block_size = superblock.inner.block_size();
|
||||
let block_groups_offset =
|
||||
(superblock.inner.first_data_block as usize + 1) * block_size;
|
||||
let block_groups_offset = Address::with_block_size(
|
||||
superblock.inner.first_data_block as usize + 1,
|
||||
0,
|
||||
superblock.inner.log_block_size + 10,
|
||||
);
|
||||
let block_groups_count = superblock
|
||||
.inner
|
||||
.block_group_count()
|
||||
|
|
@ -74,7 +78,8 @@ where
|
|||
let slice = BufferSlice::from_cast(descr, offset);
|
||||
let commit = slice.commit();
|
||||
self.buffer.commit(commit).map_err(|err| Error::from(err))?;
|
||||
offset += mem::size_of::<BlockGroupDescriptor>();
|
||||
offset =
|
||||
offset + Address::from(mem::size_of::<BlockGroupDescriptor>());
|
||||
}
|
||||
|
||||
Ok(())
|
||||
|
|
@ -83,35 +88,36 @@ where
|
|||
#[allow(dead_code)]
|
||||
fn update_inode(
|
||||
&mut self,
|
||||
&(ref inode, offset): &(Inode, usize),
|
||||
&(ref inode, offset): &(Inode, Address<S>),
|
||||
) -> Result<(), Error> {
|
||||
let slice = BufferSlice::from_cast(inode, offset);
|
||||
let commit = slice.commit();
|
||||
self.buffer.commit(commit).map_err(|err| Error::from(err))
|
||||
}
|
||||
|
||||
pub fn root_inode(&self) -> (Inode, usize) {
|
||||
pub fn root_inode(&self) -> (Inode, Address<S>) {
|
||||
self.inode_nth(2).unwrap()
|
||||
}
|
||||
|
||||
pub fn inode_nth(&self, index: usize) -> Option<(Inode, usize)> {
|
||||
pub fn inode_nth(&self, index: usize) -> Option<(Inode, Address<S>)> {
|
||||
self.inodes_nth(index).next()
|
||||
}
|
||||
|
||||
pub fn inodes<'a>(&'a self) -> Inodes<'a, B> {
|
||||
pub fn inodes<'a>(&'a self) -> Inodes<'a, S, B> {
|
||||
self.inodes_nth(1)
|
||||
}
|
||||
|
||||
pub fn inodes_nth<'a>(&'a self, index: usize) -> Inodes<'a, B> {
|
||||
pub fn inodes_nth<'a>(&'a self, index: usize) -> Inodes<'a, S, B> {
|
||||
assert!(index > 0, "inodes are 1-indexed");
|
||||
Inodes {
|
||||
buffer: &self.buffer,
|
||||
block_groups: &self.block_groups.inner,
|
||||
block_size: self.block_size(),
|
||||
log_block_size: self.log_block_size(),
|
||||
inode_size: self.inode_size(),
|
||||
inodes_per_group: self.inodes_count(),
|
||||
inodes_count: self.total_inodes_count(),
|
||||
index,
|
||||
_phantom: PhantomData,
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -163,23 +169,29 @@ where
|
|||
pub fn block_size(&self) -> usize {
|
||||
self.superblock().block_size()
|
||||
}
|
||||
|
||||
pub fn log_block_size(&self) -> u32 {
|
||||
self.superblock().log_block_size
|
||||
}
|
||||
}
|
||||
|
||||
pub struct Inodes<'a, B: 'a + Buffer<u8, usize>> {
|
||||
pub struct Inodes<'a, S: Size, B: 'a + Buffer<u8, Address<S>>> {
|
||||
buffer: &'a B,
|
||||
block_groups: &'a [BlockGroupDescriptor],
|
||||
block_size: usize,
|
||||
log_block_size: u32,
|
||||
inode_size: usize,
|
||||
inodes_per_group: usize,
|
||||
inodes_count: usize,
|
||||
index: usize,
|
||||
_phantom: PhantomData<S>,
|
||||
}
|
||||
|
||||
impl<'a, B: 'a + Buffer<u8, usize>> Iterator for Inodes<'a, B>
|
||||
impl<'a, S: Size + Copy, B: 'a + Buffer<u8, Address<S>>> Iterator
|
||||
for Inodes<'a, S, B>
|
||||
where
|
||||
Error: From<B::Error>,
|
||||
{
|
||||
type Item = (Inode, usize);
|
||||
type Item = (Inode, Address<S>);
|
||||
|
||||
fn next(&mut self) -> Option<Self::Item> {
|
||||
if self.index < self.inodes_count {
|
||||
|
|
@ -190,8 +202,11 @@ where
|
|||
let inodes_block =
|
||||
self.block_groups[block_group].inode_table_block as usize;
|
||||
|
||||
let offset =
|
||||
inodes_block * self.block_size + index * self.inode_size;
|
||||
let offset = Address::with_block_size(
|
||||
inodes_block,
|
||||
index * self.inode_size,
|
||||
self.log_block_size,
|
||||
);
|
||||
unsafe {
|
||||
Inode::find_inode(self.buffer, offset, self.inode_size).ok()
|
||||
}
|
||||
|
|
@ -206,6 +221,7 @@ mod tests {
|
|||
use std::fs::File;
|
||||
use std::cell::RefCell;
|
||||
|
||||
use block::{Address, Size512};
|
||||
use buffer::Buffer;
|
||||
|
||||
use super::Ext2;
|
||||
|
|
@ -213,13 +229,21 @@ mod tests {
|
|||
#[test]
|
||||
fn file_len() {
|
||||
let file = RefCell::new(File::open("ext2.img").unwrap());
|
||||
assert_eq!(unsafe { file.slice_unchecked(1024..2048).len() }, 1024);
|
||||
assert_eq!(
|
||||
unsafe {
|
||||
file.slice_unchecked(
|
||||
Address::<Size512>::from(1024_usize)
|
||||
..Address::<Size512>::from(2048_usize),
|
||||
).len()
|
||||
},
|
||||
1024
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn file() {
|
||||
let file = RefCell::new(File::open("ext2.img").unwrap());
|
||||
let fs = Ext2::new(file);
|
||||
let fs = Ext2::<Size512, _>::new(file);
|
||||
|
||||
assert!(
|
||||
fs.is_ok(),
|
||||
|
|
@ -237,7 +261,7 @@ mod tests {
|
|||
#[test]
|
||||
fn inodes() {
|
||||
let file = RefCell::new(File::open("ext2.img").unwrap());
|
||||
let fs = Ext2::new(file);
|
||||
let fs = Ext2::<Size512, _>::new(file);
|
||||
|
||||
assert!(
|
||||
fs.is_ok(),
|
||||
|
|
|
|||
|
|
@ -4,6 +4,7 @@ use core::fmt::{self, Debug};
|
|||
use alloc::Vec;
|
||||
|
||||
use error::Error;
|
||||
use block::{Address, Size};
|
||||
use buffer::Buffer;
|
||||
|
||||
/// The Block Group Descriptor Table contains a descriptor for each block group
|
||||
|
|
@ -51,16 +52,24 @@ impl Debug for BlockGroupDescriptor {
|
|||
}
|
||||
|
||||
impl BlockGroupDescriptor {
|
||||
pub unsafe fn find_descriptor<B: Buffer<u8, usize>>(
|
||||
pub unsafe fn find_descriptor<
|
||||
S: Size + Copy + PartialOrd,
|
||||
B: Buffer<u8, Address<S>>,
|
||||
>(
|
||||
haystack: &B,
|
||||
offset: usize,
|
||||
) -> Result<(BlockGroupDescriptor, usize), Error>
|
||||
offset: Address<S>,
|
||||
) -> Result<(BlockGroupDescriptor, Address<S>), Error>
|
||||
where
|
||||
Error: From<B::Error>,
|
||||
{
|
||||
let end = offset + mem::size_of::<BlockGroupDescriptor>();
|
||||
let end =
|
||||
offset + Address::from(mem::size_of::<BlockGroupDescriptor>());
|
||||
if haystack.len() < end {
|
||||
return Err(Error::OutOfBounds(end));
|
||||
return Err(Error::AddressOutOfBounds(
|
||||
end.block(),
|
||||
end.offset(),
|
||||
end.block_size(),
|
||||
));
|
||||
}
|
||||
|
||||
let descr = haystack
|
||||
|
|
@ -70,22 +79,31 @@ impl BlockGroupDescriptor {
|
|||
Ok(descr)
|
||||
}
|
||||
|
||||
pub unsafe fn find_descriptor_table<B: Buffer<u8, usize>>(
|
||||
pub unsafe fn find_descriptor_table<
|
||||
S: Size + Copy + PartialOrd,
|
||||
B: Buffer<u8, Address<S>>,
|
||||
>(
|
||||
haystack: &B,
|
||||
offset: usize,
|
||||
offset: Address<S>,
|
||||
count: usize,
|
||||
) -> Result<(Vec<BlockGroupDescriptor>, usize), Error>
|
||||
) -> Result<(Vec<BlockGroupDescriptor>, Address<S>), Error>
|
||||
where
|
||||
Error: From<B::Error>,
|
||||
{
|
||||
let end = offset + count * mem::size_of::<BlockGroupDescriptor>();
|
||||
let end = offset
|
||||
+ Address::from(count * mem::size_of::<BlockGroupDescriptor>());
|
||||
if haystack.len() < end {
|
||||
return Err(Error::OutOfBounds(end));
|
||||
return Err(Error::AddressOutOfBounds(
|
||||
end.block(),
|
||||
end.offset(),
|
||||
end.block_size(),
|
||||
));
|
||||
}
|
||||
|
||||
let mut vec = Vec::with_capacity(count);
|
||||
for i in 0..count {
|
||||
let offset = offset + i * mem::size_of::<BlockGroupDescriptor>();
|
||||
let offset = offset
|
||||
+ Address::from(i * mem::size_of::<BlockGroupDescriptor>());
|
||||
vec.push({
|
||||
BlockGroupDescriptor::find_descriptor(haystack, offset)?.0
|
||||
});
|
||||
|
|
@ -97,13 +115,18 @@ impl BlockGroupDescriptor {
|
|||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use block::{Address, Size512};
|
||||
use super::*;
|
||||
|
||||
#[test]
|
||||
fn find() {
|
||||
let buffer = vec![0_u8; 4096];
|
||||
let table = unsafe {
|
||||
BlockGroupDescriptor::find_descriptor_table(&buffer, 2048, 8)
|
||||
BlockGroupDescriptor::find_descriptor_table(
|
||||
&buffer,
|
||||
Address::<Size512>::new(4, 0),
|
||||
8,
|
||||
)
|
||||
};
|
||||
assert!(
|
||||
table.is_ok(),
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@ use core::mem;
|
|||
use core::fmt::{self, Debug};
|
||||
|
||||
use error::Error;
|
||||
use block::{Address, Size};
|
||||
use buffer::Buffer;
|
||||
|
||||
/// An inode is a structure on the disk that represents a file, directory,
|
||||
|
|
@ -96,11 +97,14 @@ impl Debug for Inode {
|
|||
}
|
||||
|
||||
impl Inode {
|
||||
pub unsafe fn find_inode<B: Buffer<u8, usize>>(
|
||||
pub unsafe fn find_inode<
|
||||
S: Size + Copy + PartialOrd,
|
||||
B: Buffer<u8, Address<S>>,
|
||||
>(
|
||||
haystack: &B,
|
||||
offset: usize,
|
||||
offset: Address<S>,
|
||||
size: usize,
|
||||
) -> Result<(Inode, usize), Error>
|
||||
) -> Result<(Inode, Address<S>), Error>
|
||||
where
|
||||
Error: From<B::Error>,
|
||||
{
|
||||
|
|
@ -108,9 +112,13 @@ impl Inode {
|
|||
unimplemented!("inodes with a size != 128");
|
||||
}
|
||||
|
||||
let end = offset + size;
|
||||
let end = offset + Address::from(size);
|
||||
if haystack.len() < end {
|
||||
return Err(Error::OutOfBounds(end));
|
||||
return Err(Error::AddressOutOfBounds(
|
||||
end.block(),
|
||||
end.offset(),
|
||||
end.block_size(),
|
||||
));
|
||||
}
|
||||
|
||||
let inode = haystack
|
||||
|
|
|
|||
|
|
@ -2,6 +2,7 @@ use core::mem;
|
|||
use core::fmt::{self, Debug};
|
||||
|
||||
use error::Error;
|
||||
use block::{Address, Size};
|
||||
use buffer::Buffer;
|
||||
|
||||
/// Ext2 signature (0xef53), used to help confirm the presence of Ext2 on a
|
||||
|
|
@ -194,16 +195,20 @@ impl Debug for Superblock {
|
|||
}
|
||||
|
||||
impl Superblock {
|
||||
pub unsafe fn find<B: Buffer<u8, usize>>(
|
||||
pub unsafe fn find<S: Size + Copy + PartialOrd, B: Buffer<u8, Address<S>>>(
|
||||
haystack: &B,
|
||||
) -> Result<(Superblock, usize), Error>
|
||||
) -> Result<(Superblock, Address<S>), Error>
|
||||
where
|
||||
Error: From<B::Error>,
|
||||
{
|
||||
let offset = 1024;
|
||||
let end = offset + mem::size_of::<Superblock>();
|
||||
let offset = Address::from(1024_usize);
|
||||
let end = offset + Address::from(mem::size_of::<Superblock>());
|
||||
if haystack.len() < end {
|
||||
return Err(Error::OutOfBounds(end));
|
||||
return Err(Error::AddressOutOfBounds(
|
||||
end.block(),
|
||||
end.offset(),
|
||||
end.block_size(),
|
||||
));
|
||||
}
|
||||
|
||||
let superblock = {
|
||||
|
|
@ -291,6 +296,7 @@ bitflags! {
|
|||
|
||||
#[cfg(test)]
|
||||
mod tests {
|
||||
use block::Size512;
|
||||
use super::*;
|
||||
|
||||
#[test]
|
||||
|
|
@ -299,7 +305,7 @@ mod tests {
|
|||
// magic
|
||||
buffer[1024 + 56] = EXT2_MAGIC as u8;
|
||||
buffer[1024 + 57] = (EXT2_MAGIC >> 8) as u8;
|
||||
let superblock = unsafe { Superblock::find(&buffer) };
|
||||
let superblock = unsafe { Superblock::find::<Size512, _>(&buffer) };
|
||||
assert!(
|
||||
superblock.is_ok(),
|
||||
"Err({:?})",
|
||||
|
|
@ -314,7 +320,7 @@ mod tests {
|
|||
use std::fs::File;
|
||||
|
||||
let file = RefCell::new(File::open("ext2.img").unwrap());
|
||||
let superblock = unsafe { Superblock::find(&file) };
|
||||
let superblock = unsafe { Superblock::find::<Size512, _>(&file) };
|
||||
assert!(
|
||||
superblock.is_ok(),
|
||||
"Err({:?})",
|
||||
|
|
|
|||
Reference in New Issue