feature: Stdin/Stdout/Stderr structs

Cargo.lock

@@ -97,6 +97,15 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "lazy_static"
+version = "1.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+dependencies = [
+ "spin",
+]
+
 [[package]]
 name = "libsys"
 version = "0.1.0"
@@ -108,6 +117,7 @@ dependencies = [
 name = "libusr"
 version = "0.1.0"
 dependencies = [
+ "lazy_static",
  "libsys",
 ]
 
@@ -195,6 +205,12 @@ version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 
+[[package]]
+name = "spin"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
+
 [[package]]
 name = "static_assertions"
 version = "1.1.0"

libusr/Cargo.toml

@@ -7,3 +7,4 @@ edition = "2021"
 
 [dependencies]
 libsys = { path = "../libsys", features = ["user"] }
+lazy_static = { version = "^1.4.0", features = ["spin_no_std"] }

libusr/src/file.rs

@@ -1,12 +1,26 @@
+use crate::io::{AsRawFd, Error};
+use crate::os;
+use crate::trace;
 use libsys::stat::FileDescriptor;
-use crate::io;
 
 pub struct File {
-    fd: FileDescriptor
+    fd: FileDescriptor,
 }
 
 impl File {
-    pub fn open(path: &str) -> Result<File, io::Error> {
+    pub fn open(path: &str) -> Result<File, Error> {
         todo!()
     }
 }
+
+impl AsRawFd for File {
+    fn as_raw_fd(&self) -> FileDescriptor {
+        self.fd
+    }
+}
+
+impl Drop for File {
+    fn drop(&mut self) {
+        todo!();
+    }
+}

libusr/src/io.rs

@@ -1,65 +0,0 @@
-use core::fmt;
-use libsys::{
-    calls::{sys_fstatat, sys_write},
-    stat::{Stat, FileDescriptor},
-};
-
-// TODO populate this type
-pub struct Error;
-
-pub fn stat(pathname: &str) -> Result<Stat, Error> {
-    let mut buf = Stat::default();
-    // TODO error handling
-    let res = unsafe { sys_fstatat(None, pathname, &mut buf, 0).unwrap() };
-    Ok(buf)
-}
-
-// print!/println! group
-
-#[macro_export]
-macro_rules! print {
-    ($($args:tt)+) => ($crate::io::_print($crate::sys::FileDescriptor::STDOUT, format_args!($($args)+)))
-}
-
-#[macro_export]
-macro_rules! println {
-    ($($args:tt)+) => (print!("{}\n", format_args!($($args)+)))
-}
-
-#[macro_export]
-macro_rules! eprint {
-    ($($args:tt)+) => ($crate::io::_print($crate::sys::FileDescriptor::STDERR, format_args!($($args)+)))
-}
-
-#[macro_export]
-macro_rules! eprintln {
-    ($($args:tt)+) => (eprint!("{}\n", format_args!($($args)+)))
-}
-
-struct BufferWriter<'a> {
-    buf: &'a mut [u8],
-    pos: usize,
-}
-
-impl fmt::Write for BufferWriter<'_> {
-    fn write_str(&mut self, s: &str) -> fmt::Result {
-        for byte in s.bytes() {
-            self.buf[self.pos] = byte;
-            self.pos += 1;
-        }
-        Ok(())
-    }
-}
-
-pub fn _print(fd: FileDescriptor, args: fmt::Arguments) {
-    use core::fmt::Write;
-    static mut BUFFER: [u8; 4096] = [0; 4096];
-    let mut writer = BufferWriter {
-        buf: unsafe { &mut BUFFER },
-        pos: 0,
-    };
-    writer.write_fmt(args).ok();
-    unsafe {
-        sys_write(fd, &BUFFER[..writer.pos]);
-    }
-}

libusr/src/io/error.rs

@@ -0,0 +1,35 @@
+use libsys::error::Errno;
+
+#[derive(Debug)]
+pub struct Error {
+    repr: Repr,
+}
+
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Hash, Ord, PartialOrd)]
+pub enum ErrorKind {
+    NotFound,
+    PermissionDenied,
+    InvalidData,
+}
+
+#[derive(Debug)]
+enum Repr {
+    Os(Errno),
+    Simple(ErrorKind),
+}
+
+impl Error {
+    pub const fn new(kind: ErrorKind) -> Self {
+        Self {
+            repr: Repr::Simple(kind),
+        }
+    }
+}
+
+impl From<Errno> for Error {
+    fn from(e: Errno) -> Self {
+        Self {
+            repr: Repr::Os(e)
+        }
+    }
+}

libusr/src/io/mod.rs

@@ -0,0 +1,32 @@
+use libsys::{
+    calls::sys_fstatat,
+    stat::{FileDescriptor, Stat},
+};
+use core::fmt;
+
+mod error;
+pub use error::{Error, ErrorKind};
+mod writer;
+pub use writer::{_print};
+mod stdio;
+pub use stdio::{stderr, stdin, stdout, Stderr, Stdin, Stdout};
+
+pub trait Read {
+    fn read(&mut self, bytes: &mut [u8]) -> Result<usize, Error>;
+}
+
+pub trait Write {
+    fn write(&mut self, bytes: &[u8]) -> Result<usize, Error>;
+    fn write_fmt(&mut self, args: fmt::Arguments<'_>) -> Result<(), Error>;
+}
+
+pub trait AsRawFd {
+    fn as_raw_fd(&self) -> FileDescriptor;
+}
+
+pub fn stat(pathname: &str) -> Result<Stat, Error> {
+    let mut buf = Stat::default();
+    // TODO error handling
+    let res = sys_fstatat(None, pathname, &mut buf, 0).unwrap();
+    Ok(buf)
+}

libusr/src/io/stdio.rs

@@ -0,0 +1,130 @@
+use libsys::{
+    stat::FileDescriptor,
+    calls::{sys_read, sys_write}
+};
+use crate::io::{Read, Write, Error};
+use crate::sync::{Mutex, MutexGuard};
+use core::fmt;
+
+struct InputInner {
+    fd: FileDescriptor
+}
+struct OutputInner {
+    fd: FileDescriptor
+}
+
+pub struct StdinLock<'a> {
+    lock: MutexGuard<'a, InputInner>
+}
+
+pub struct StdoutLock<'a> {
+    lock: MutexGuard<'a, OutputInner>
+}
+
+pub struct StderrLock<'a> {
+    lock: MutexGuard<'a, OutputInner>
+}
+
+pub struct Stdin {
+    inner: &'static Mutex<InputInner>,
+}
+
+pub struct Stdout {
+    inner: &'static Mutex<OutputInner>
+}
+
+pub struct Stderr {
+    inner: &'static Mutex<OutputInner>
+}
+
+// STDIN
+
+impl Read for InputInner {
+    fn read(&mut self, bytes: &mut [u8]) -> Result<usize, Error> {
+        sys_read(self.fd, bytes).map_err(Error::from)
+    }
+}
+
+impl Read for Stdin {
+    fn read(&mut self, bytes: &mut [u8]) -> Result<usize, Error> {
+        self.inner.lock().read(bytes)
+    }
+}
+
+// STDOUT/STDERR
+
+impl fmt::Write for OutputInner {
+    fn write_str(&mut self, s: &str) -> fmt::Result {
+        self.write(s.as_bytes()).map(|_| ()).map_err(|_| todo!())
+    }
+}
+
+impl Write for OutputInner {
+    fn write(&mut self, bytes: &[u8]) -> Result<usize, Error> {
+        sys_write(self.fd, bytes).map_err(Error::from)
+    }
+
+    fn write_fmt(&mut self, args: fmt::Arguments<'_>) -> Result<(), Error> {
+        fmt::Write::write_fmt(self, args).map_err(|_| todo!())
+    }
+}
+
+impl Write for Stdout {
+    fn write(&mut self, bytes: &[u8]) -> Result<usize, Error> {
+        self.inner.lock().write(bytes)
+    }
+
+    fn write_fmt(&mut self, args: fmt::Arguments<'_>) -> Result<(), Error> {
+        self.inner.lock().write_fmt(args)
+    }
+}
+
+impl Write for Stderr {
+    fn write(&mut self, bytes: &[u8]) -> Result<usize, Error> {
+        self.inner.lock().write(bytes)
+    }
+
+    fn write_fmt(&mut self, args: fmt::Arguments<'_>) -> Result<(), Error> {
+        self.inner.lock().write_fmt(args)
+    }
+}
+
+impl Stdout {
+    pub fn lock(&self) -> StdoutLock {
+        StdoutLock {
+            lock: self.inner.lock()
+        }
+    }
+}
+
+impl Stderr {
+    pub fn lock(&self) -> StderrLock {
+        StderrLock {
+            lock: self.inner.lock()
+        }
+    }
+}
+
+lazy_static! {
+    static ref STDIN: Mutex<InputInner> = Mutex::new(InputInner {
+        fd: FileDescriptor::STDIN
+    });
+    static ref STDOUT: Mutex<OutputInner> = Mutex::new(OutputInner {
+        fd: FileDescriptor::STDOUT
+    });
+    static ref STDERR: Mutex<OutputInner> = Mutex::new(OutputInner {
+        fd: FileDescriptor::STDOUT
+    });
+}
+
+pub fn stdin() -> Stdin {
+    Stdin { inner: &STDIN }
+}
+
+pub fn stdout() -> Stdout {
+    Stdout { inner: &STDOUT }
+}
+
+pub fn stderr() -> Stderr {
+    Stderr { inner: &STDERR }
+}

libusr/src/io/writer.rs

@@ -0,0 +1,26 @@
+use core::fmt;
+use crate::io::{self, Write};
+
+#[macro_export]
+macro_rules! print {
+    ($($args:tt)+) => ($crate::io::_print($crate::io::stdout, format_args!($($args)+)))
+}
+
+#[macro_export]
+macro_rules! println {
+    ($($args:tt)+) => (print!("{}\n", format_args!($($args)+)))
+}
+
+#[macro_export]
+macro_rules! eprint {
+    ($($args:tt)+) => ($crate::io::_print($crate::io::stderr, format_args!($($args)+)))
+}
+
+#[macro_export]
+macro_rules! eprintln {
+    ($($args:tt)+) => (eprint!("{}\n", format_args!($($args)+)))
+}
+
+pub fn _print<T: Write>(out: fn() -> T, args: fmt::Arguments) {
+    out().write_fmt(args).expect("stdout/stderr write failed");
+}

libusr/src/lib.rs

@@ -4,24 +4,20 @@
 use core::panic::PanicInfo;
 use libsys::proc::ExitCode;
 
+#[macro_use]
+extern crate lazy_static;
+
+pub mod file;
 pub mod io;
 pub mod os;
-pub mod file;
-
-pub mod sys {
-    pub use libsys::signal::{Signal, SignalDestination};
-    pub use libsys::termios;
-    pub use libsys::calls::*;
-    pub use libsys::stat::{self, FileDescriptor};
-}
+pub mod sys;
+pub mod sync;
 
 #[inline(never)]
 extern "C" fn _signal_handler(arg: sys::Signal) -> ! {
     trace!("Entered signal handler: arg={:?}", arg);
-    unsafe {
     sys::sys_ex_sigreturn();
 }
-}
 
 static mut SIGNAL_STACK: [u8; 4096] = [0; 4096];
 
@@ -31,17 +27,22 @@ extern "C" fn _start(_arg: usize) -> ! {
     extern "Rust" {
         fn main() -> i32;
     }
-    unsafe {
-        SIGNAL_STACK[0] = 1;
-        sys::sys_ex_signal(_signal_handler as usize, SIGNAL_STACK.as_ptr() as usize + 4096);
 
-        sys::sys_exit(ExitCode::from(main()));
+    unsafe {
+        sys::sys_ex_signal(
+            _signal_handler as usize,
+            SIGNAL_STACK.as_ptr() as usize + 4096,
+        )
+        .unwrap();
     }
+
+    let res = unsafe { main() };
+    sys::sys_exit(ExitCode::from(res));
 }
 
 #[panic_handler]
 fn panic_handler(pi: &PanicInfo) -> ! {
-    // TODO formatted messages
+    // TODO print to stdout/stderr (if available)
     trace!("Panic ocurred: {}", pi);
     sys::sys_exit(ExitCode::from(-1));
 }

libusr/src/os.rs

@@ -3,35 +3,6 @@ use core::fmt;
 use core::mem::{size_of, MaybeUninit};
 use libsys::{ioctl::IoctlCmd, stat::FileDescriptor, termios::Termios};
 
-pub fn get_tty_attrs(fd: FileDescriptor) -> Result<Termios, &'static str> {
-    let mut termios = MaybeUninit::<Termios>::uninit();
-    let res = sys::sys_ioctl(
-        fd,
-        IoctlCmd::TtyGetAttributes,
-        termios.as_mut_ptr() as usize,
-        size_of::<Termios>(),
-    )
-    .unwrap();
-    if res != size_of::<Termios>() {
-        return Err("Failed");
-    }
-    Ok(unsafe { termios.assume_init() })
-}
-
-pub fn set_tty_attrs(fd: FileDescriptor, attrs: &Termios) -> Result<(), &'static str> {
-    let res = sys::sys_ioctl(
-        fd,
-        IoctlCmd::TtySetAttributes,
-        attrs as *const _ as usize,
-        size_of::<Termios>(),
-    )
-    .unwrap();
-    if res != size_of::<Termios>() {
-        return Err("Failed");
-    }
-    Ok(())
-}
-
 #[macro_export]
 macro_rules! trace {
     ($($args:tt)+) => ($crate::os::_trace(format_args!($($args)+)))
@@ -60,7 +31,5 @@ pub fn _trace(args: fmt::Arguments) {
         pos: 0,
     };
     writer.write_fmt(args).ok();
-    unsafe {
-        sys::sys_ex_debug_trace(&BUFFER[..writer.pos]);
-    }
+    sys::sys_ex_debug_trace(unsafe { &BUFFER[..writer.pos] }).ok();
 }

libusr/src/sync.rs

@@ -0,0 +1,54 @@
+use core::cell::UnsafeCell;
+use core::ops::{Deref, DerefMut};
+use crate::sys::RawMutex;
+
+pub struct Mutex<T> {
+    inner: RawMutex,
+    data: UnsafeCell<T>
+}
+
+pub struct MutexGuard<'a, T> {
+    data: &'a mut T,
+    lock: &'a RawMutex,
+}
+
+impl<T> Mutex<T> {
+    pub fn new(t: T) -> Self {
+        Self {
+            inner: RawMutex::new(),
+            data: UnsafeCell::new(t)
+        }
+    }
+
+    pub fn lock(&self) -> MutexGuard<'_, T> {
+        unsafe {
+            self.inner.lock();
+            MutexGuard {
+                data: (&mut *self.data.get()),
+                lock: &self.inner
+            }
+        }
+    }
+}
+
+impl<'a, T> Drop for MutexGuard<'a, T> {
+    fn drop(&mut self) {
+        unsafe { self.lock.release(); }
+    }
+}
+
+impl<'a, T> Deref for MutexGuard<'a, T> {
+    type Target = T;
+
+    fn deref(&self) -> &T {
+        self.data
+    }
+}
+
+impl<'a, T> DerefMut for MutexGuard<'a, T> {
+    fn deref_mut(&mut self) -> &mut T {
+        self.data
+    }
+}
+
+unsafe impl<T> Sync for Mutex<T> {}

libusr/src/sys/mod.rs

@@ -0,0 +1,39 @@
+pub use libsys::signal::{Signal, SignalDestination};
+pub use libsys::termios;
+pub use libsys::calls::*;
+pub use libsys::stat::{self, FileDescriptor};
+
+use core::sync::atomic::{Ordering, AtomicBool};
+
+// TODO replace with a proper mutex impl
+pub(crate) struct RawMutex {
+    inner: AtomicBool
+}
+
+impl RawMutex {
+    pub const fn new() -> Self {
+        Self { inner: AtomicBool::new(false) }
+    }
+
+    #[inline]
+    unsafe fn try_lock(&self) -> bool {
+        self.inner.compare_exchange_weak(false, true, Ordering::Acquire, Ordering::Relaxed).is_ok()
+    }
+
+    #[inline]
+    unsafe fn is_locked(&self) -> bool {
+        self.inner.load(Ordering::Acquire)
+    }
+
+    #[inline]
+    pub unsafe fn lock(&self) {
+        while !self.try_lock() {
+            asm!("nop");
+        }
+    }
+
+    #[inline]
+    pub unsafe fn release(&self) {
+        self.inner.store(false, Ordering::Release);
+    }
+}

user/src/shell/main.rs

@@ -4,54 +4,22 @@
 #[macro_use]
 extern crate libusr;
 
-use libusr::sys::stat::{FdSet, FileDescriptor};
-use libusr::sys::{Signal, SignalDestination};
-
-fn readline(fd: FileDescriptor, buf: &mut [u8]) -> Result<&str, ()> {
-    // select() just for test
-    loop {
-        let mut rfds = FdSet::empty();
-        rfds.set(fd);
-        let res = unsafe {
-            libusr::sys::sys_select(Some(&mut rfds), None, 1_000_000_000).unwrap()
-        };
-        if res == 0 {
-            continue;
-        }
-        if !rfds.is_set(fd) {
-            panic!();
-        }
-
-        let count = unsafe { libusr::sys::sys_read(fd, buf).unwrap() };
-        return core::str::from_utf8(&buf[..count as usize]).map_err(|_| ());
-    }
-}
+use libusr::io::{self, Read};
 
 #[no_mangle]
 fn main() -> i32 {
     let mut buf = [0; 512];
+    let mut stdin = io::stdin();
+
+    eprintln!("stderr test");
 
     loop {
-        print!("> ");
-        let line = readline(FileDescriptor::STDIN, &mut buf).unwrap();
-        if line.is_empty() {
-            break;
-        }
-        let line = line.trim_end_matches('\n');
-
-        println!(":: {:?}", line);
-
-        if line == "test" {
-            unsafe {
-                libusr::sys::sys_ex_kill(SignalDestination::This, Signal::Interrupt);
-            }
-            trace!("Returned from signal");
-            continue;
-        }
-
-        if line == "quit" || line == "exit" {
+        let count = stdin.read(&mut buf).unwrap();
+        if count == 0 {
             break;
         }
+        let line = core::str::from_utf8(&buf[..count]).unwrap();
+        println!("{:?}", line);
     }
 
     0