Basic no_std support

Cargo.lock

@@ -41,6 +41,14 @@ dependencies = [
  "time 0.1.39 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "core_io"
+version = "0.1.20180307"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rustc_version 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "env_logger"
 version = "0.5.10"
@@ -60,6 +68,7 @@ dependencies = [
  "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "chrono 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "core_io 0.1.20180307 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.5.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -149,6 +158,19 @@ dependencies = [
  "ucd-util 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rustc_version"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "semver 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "semver"
+version = "0.1.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "termcolor"
 version = "0.3.6"
@@ -243,6 +265,7 @@ dependencies = [
 "checksum byteorder 1.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "73b5bdfe7ee3ad0b99c9801d58807a9dbc9e09196365b0203853b99889ab3c87"
 "checksum cfg-if 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "405216fd8fe65f718daa7102ea808a946b6ce40c742998fbfd3463645552de18"
 "checksum chrono 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1cce36c92cb605414e9b824f866f5babe0a0368e39ea07393b9b63cf3844c0e6"
+"checksum core_io 0.1.20180307 (registry+https://github.com/rust-lang/crates.io-index)" = "52c2fc3ad457529bd2ac28471ffc4d8971656de79d3b5fb745ba8117c7c997cc"
 "checksum env_logger 0.5.10 (registry+https://github.com/rust-lang/crates.io-index)" = "0e6e40ebb0e66918a37b38c7acab4e10d299e0463fe2af5d29b9cc86710cfd2a"
 "checksum humantime 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "0484fda3e7007f2a4a0d9c3a703ca38c71c54c55602ce4660c419fd32e188c9e"
 "checksum lazy_static 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c8f31047daa365f19be14b47c29df4f7c3b581832407daabe6ae77397619237d"
@@ -256,6 +279,8 @@ dependencies = [
 "checksum redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7e891cfe48e9100a70a3b6eb652fef28920c117d366339687bd5576160db0f76"
 "checksum regex 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "75ecf88252dce580404a22444fc7d626c01815debba56a7f4f536772a5ff19d3"
 "checksum regex-syntax 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8f1ac0f60d675cc6cf13a20ec076568254472551051ad5dd050364d70671bf6b"
+"checksum rustc_version 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "c5f5376ea5e30ce23c03eb77cbe4962b988deead10910c372b226388b594c084"
+"checksum semver 0.1.20 (registry+https://github.com/rust-lang/crates.io-index)" = "d4f410fedcf71af0345d7607d246e7ad15faaadd49d240ee3b24e5dc21a820ac"
 "checksum termcolor 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "adc4587ead41bf016f11af03e55a624c06568b5a19db4e90fde573d805074f83"
 "checksum termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "689a3bdfaab439fd92bc87df5c4c78417d3cbe537487274e9b0b2dce76e92096"
 "checksum thread_local 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "279ef31c19ededf577bfd12dfae728040a21f635b06a24cd670ff510edd38963"

Cargo.toml

@@ -4,7 +4,7 @@ version = "0.2.0"
 authors = ["Rafał Harabień <rafalh1992@o2.pl>"]
 repository = "https://github.com/rafalh/rust-fatfs"
 readme = "README.md"
-keywords = ["fat", "filesystem"]
+keywords = ["fat", "filesystem", "no_std"]
 categories = ["filesystem"]
 license = "MIT"
 description = """
@@ -18,13 +18,15 @@ exclude = [
 travis-ci = { repository = "rafalh/rust-fatfs" }
 
 [features]
-default = ["chrono"]
+std = []
+default = ["chrono", "std"]
 
 [dependencies]
 byteorder = "1"
 bitflags = "1.0"
 log = "0.4"
 chrono = { version = "0.4", optional = true }
+core_io = { version = "0.1", features = ["collections"], optional = true }
 
 [dev-dependencies]
 env_logger = "0.5"

README.md

@@ -39,6 +39,16 @@ You can start using library now:
 
 See more examples in `examples` subdirectory.
 
+no_std usage
+------------
+
+Put this in your `Cargo.toml`:
+
+    [dependencies]
+    fatfs = { version = "0.2", features = ["core_io"], default-features = false }
+
+Note: alloc crate is required at the moment so when std is disabled, custom allocator has to be provided.
+
 License
 -------
 The MIT license. See LICENSE.txt.

TODO.md

@@ -3,4 +3,4 @@ TODO
 * FsInfo sector handling
 * move file API
 * format volume API
-* no_std support
+* better no_std support

build-nostd.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+cargo build --no-default-features --features core_io

src/dir.rs

@@ -1,14 +1,18 @@
-use std::io::prelude::*;
-use std::io;
-use std::io::{ErrorKind, SeekFrom};
-use std::slice;
-use std::iter;
+use core::slice;
+use core::iter;
+
+use io::prelude::*;
+use io;
+use io::{ErrorKind, SeekFrom};
 
 use fs::{FileSystemRef, DiskSlice};
 use file::File;
 use dir_entry::{DirEntry, DirEntryData, DirFileEntryData, DirLfnEntryData, FileAttributes,
     DIR_ENTRY_SIZE, LFN_PART_LEN, LFN_ENTRY_LAST_FLAG};
 
+#[cfg(not(feature = "std"))]
+use alloc::Vec;
+
 #[derive(Clone)]
 pub(crate) enum DirRawStream<'a, 'b: 'a> {
     File(File<'a, 'b>),

src/dir_entry.rs

@@ -1,14 +1,18 @@
-use std::fmt;
-use std::io::prelude::*;
-use std::io;
-use std::io::Cursor;
-use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
+use core::fmt;
+use io::prelude::*;
+use io;
+use io::Cursor;
+use byteorder::{LittleEndian};
+use byteorder_ext::{ReadBytesExt, WriteBytesExt};
 
 #[cfg(feature = "chrono")]
 use chrono::{TimeZone, Local, Datelike, Timelike};
 #[cfg(feature = "chrono")]
 use chrono;
 
+#[cfg(not(feature = "std"))]
+use alloc::{Vec, String, string::ToString};
+
 use fs::{FileSystemRef, FatType};
 use file::File;
 use dir::{Dir, DirRawStream};

src/file.rs

@@ -1,7 +1,7 @@
-use std::cmp;
-use std::io::prelude::*;
-use std::io::{SeekFrom, ErrorKind};
-use std::io;
+use core::cmp;
+use io::prelude::*;
+use io::{SeekFrom, ErrorKind};
+use io;
 
 use fs::FileSystemRef;
 use dir_entry::{DirEntryEditor, DateTime, Date};

src/fs.rs

@@ -1,15 +1,19 @@
 use core::cell::RefCell;
 use core::cmp;
-use std::io::prelude::*;
-use std::io::{Error, ErrorKind, SeekFrom};
-use std::io;
-use byteorder::{LittleEndian, ReadBytesExt};
+use io::prelude::*;
+use io::{Error, ErrorKind, SeekFrom};
+use io;
+use byteorder::LittleEndian;
+use byteorder_ext::ReadBytesExt;
 
 use file::File;
 use dir::{DirRawStream, Dir};
 use dir_entry::DIR_ENTRY_SIZE;
 use table::{ClusterIterator, alloc_cluster, read_fat_flags};
 
+#[cfg(not(feature = "std"))]
+use alloc::{String, string::ToString};
+
 // FAT implementation based on:
 //   http://wiki.osdev.org/FAT
 //   https://www.win.tue.nl/~aeb/linux/fs/fat/fat-1.html

src/lib.rs

@@ -1,8 +1,10 @@
 #![crate_type = "lib"]
 #![crate_name = "fatfs"]
 
+#![cfg_attr(not(feature="std"), no_std)]
+#![cfg_attr(not(feature="std"), feature(alloc))]
+
 extern crate byteorder;
-extern crate core;
 
 #[macro_use]
 extern crate bitflags;
@@ -13,6 +15,13 @@ extern crate log;
 #[cfg(feature = "chrono")]
 extern crate chrono;
 
+#[cfg(not(feature = "std"))]
+extern crate core_io;
+
+#[cfg(not(feature = "std"))]
+#[macro_use]
+extern crate alloc;
+
 mod fs;
 mod dir;
 mod dir_entry;
@@ -20,6 +29,21 @@ mod file;
 mod table;
 mod utils;
 
+#[cfg(not(feature = "std"))]
+mod byteorder_core_io;
+
+#[cfg(not(feature = "std"))]
+use byteorder_core_io as byteorder_ext;
+#[cfg(feature = "std")]
+use byteorder as byteorder_ext;
+#[cfg(feature = "std")]
+use std as core;
+#[cfg(not(feature = "std"))]
+use core_io as io;
+
+#[cfg(feature = "std")]
+use std::io as io;
+
 pub use fs::*;
 pub use dir::*;
 pub use dir_entry::*;

src/table.rs

@@ -1,6 +1,7 @@
-use std::io;
-use std::io::prelude::*;
-use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
+use io;
+use io::prelude::*;
+use byteorder::LittleEndian;
+use byteorder_ext::{ReadBytesExt, WriteBytesExt};
 use fs::{FatType, FsStatusFlags, DiskSlice, ReadSeek};
 
 struct Fat<T> {

src/utils.rs

@@ -1,6 +1,6 @@
-use std::io::prelude::*;
-use std::io;
-use std::cmp;
+use io::prelude::*;
+use io;
+use core::cmp;
 
 pub trait ReadSeek: Read + Seek {}
 impl<T> ReadSeek for T where T: Read + Seek {}