Files
redox-kernel/src/scheme/debug.rs
Jeremy Soller efd64d55e1 Bug fixes for fcntl and o_cloexec
Add fcntl to schemes
Fix debug: hang
2017-04-19 21:56:09 -06:00

151 lines
4.0 KiB
Rust

use core::sync::atomic::Ordering;
use spin::Once;
use context;
use device::serial::COM1;
use scheme::*;
use sync::WaitQueue;
use syscall::flag::{EVENT_READ, F_GETFL, F_SETFL, O_ACCMODE, O_NONBLOCK};
use syscall::scheme::Scheme;
pub static DEBUG_SCHEME_ID: AtomicSchemeId = ATOMIC_SCHEMEID_INIT;
/// Input queue
static INPUT: Once<WaitQueue<u8>> = Once::new();
/// Initialize input queue, called if needed
fn init_input() -> WaitQueue<u8> {
WaitQueue::new()
}
/// Add to the input queue
pub fn debug_input(b: u8) {
let len = INPUT.call_once(init_input).send(b);
context::event::trigger(DEBUG_SCHEME_ID.load(Ordering::SeqCst), 0, EVENT_READ, len);
}
pub struct DebugScheme {
next_id: AtomicUsize,
handles: RwLock<BTreeMap<usize, usize>>
}
impl DebugScheme {
pub fn new(scheme_id: SchemeId) -> DebugScheme {
DEBUG_SCHEME_ID.store(scheme_id, Ordering::SeqCst);
DebugScheme {
next_id: AtomicUsize::new(0),
handles: RwLock::new(BTreeMap::new())
}
}
}
impl Scheme for DebugScheme {
fn open(&self, _path: &[u8], flags: usize, _uid: u32, _gid: u32) -> Result<usize> {
let id = self.next_id.fetch_add(1, Ordering::SeqCst);
self.handles.write().insert(id, flags & ! O_ACCMODE);
Ok(id)
}
fn dup(&self, id: usize, _buf: &[u8]) -> Result<usize> {
let flags = {
let handles = self.handles.read();
*handles.get(&id).ok_or(Error::new(EBADF))?
};
let new_id = self.next_id.fetch_add(1, Ordering::SeqCst);
self.handles.write().insert(new_id, flags);
Ok(new_id)
}
/// Read the file `number` into the `buffer`
///
/// Returns the number of bytes read
fn read(&self, id: usize, buf: &mut [u8]) -> Result<usize> {
let flags = {
let handles = self.handles.read();
*handles.get(&id).ok_or(Error::new(EBADF))?
};
Ok(INPUT.call_once(init_input).receive_into(buf, flags & O_NONBLOCK != O_NONBLOCK))
}
/// Write the `buffer` to the `file`
///
/// Returns the number of bytes written
fn write(&self, id: usize, buffer: &[u8]) -> Result<usize> {
let _flags = {
let handles = self.handles.read();
*handles.get(&id).ok_or(Error::new(EBADF))?
};
let mut com = COM1.lock();
for &byte in buffer.iter() {
com.send(byte);
}
Ok(buffer.len())
}
fn fcntl(&self, id: usize, cmd: usize, arg: usize) -> Result<usize> {
let mut handles = self.handles.write();
if let Some(flags) = handles.get_mut(&id) {
match cmd {
F_GETFL => Ok(*flags),
F_SETFL => {
*flags = arg & ! O_ACCMODE;
Ok(0)
},
_ => Err(Error::new(EINVAL))
}
} else {
Err(Error::new(EBADF))
}
}
fn fevent(&self, id: usize, _flags: usize) -> Result<usize> {
let _flags = {
let handles = self.handles.read();
*handles.get(&id).ok_or(Error::new(EBADF))?
};
Ok(0)
}
fn fpath(&self, id: usize, buf: &mut [u8]) -> Result<usize> {
let _flags = {
let handles = self.handles.read();
*handles.get(&id).ok_or(Error::new(EBADF))?
};
let mut i = 0;
let scheme_path = b"debug:";
while i < buf.len() && i < scheme_path.len() {
buf[i] = scheme_path[i];
i += 1;
}
Ok(i)
}
fn fsync(&self, id: usize) -> Result<usize> {
let _flags = {
let handles = self.handles.read();
*handles.get(&id).ok_or(Error::new(EBADF))?
};
Ok(0)
}
/// Close the file `number`
fn close(&self, id: usize) -> Result<usize> {
let _flags = {
let mut handles = self.handles.write();
handles.remove(&id).ok_or(Error::new(EBADF))?
};
Ok(0)
}
}