Merge branch 'ptyd-improvements' into 'main'

ptyd: implement TIOCGPTN and TIOC{S,G}PTLCK

See merge request redox-os/base!276

drivers/redoxerd/src/main.rs

@@ -82,7 +82,7 @@ fn handle(
 
 fn getpty(columns: u32, lines: u32) -> io::Result<(RawFd, String)> {
     let master = libredox::call::open(
-        "/scheme/pty",
+        "/scheme/pty/ptmx",
         libredox::flag::O_CLOEXEC
             | libredox::flag::O_RDWR
             | libredox::flag::O_CREAT

ptyd/src/controlterm.rs

@@ -6,6 +6,7 @@ use syscall::flag::{EventFlags, F_GETFL, F_SETFL, O_ACCMODE, O_NONBLOCK};
 
 use crate::pty::Pty;
 use crate::resource::Resource;
+use scheme_utils::FpathWriter;
 
 /// Read side of a pipe
 pub struct PtyControlTerm {
@@ -36,7 +37,10 @@ impl Resource for PtyControlTerm {
     }
 
     fn path(&mut self, buf: &mut [u8]) -> Result<usize> {
-        self.pty.borrow_mut().path(buf)
+        FpathWriter::with(buf, "pty", |w| {
+            write!(w, "{}", "ptmx").unwrap();
+            Ok(())
+        })
     }
 
     fn read(&mut self, buf: &mut [u8]) -> Result<usize> {

ptyd/src/main.rs

@@ -7,6 +7,8 @@ use syscall::data::TimeSpec;
 
 mod controlterm;
 mod pgrp;
+mod ptlock;
+mod ptname;
 mod pty;
 mod resource;
 mod scheme;

ptyd/src/ptlock.rs

@@ -0,0 +1,93 @@
+use std::cell::RefCell;
+use std::rc::Weak;
+
+use syscall::error::{Error, Result, EBADF, EINVAL, EPIPE};
+use syscall::flag::{EventFlags, F_GETFL, F_SETFL, O_ACCMODE};
+
+use crate::pty::Pty;
+use crate::resource::Resource;
+
+/// Read side of a pipe
+pub struct PtyLock {
+    pty: Weak<RefCell<Pty>>,
+    flags: usize,
+}
+
+impl PtyLock {
+    pub fn new(pty: Weak<RefCell<Pty>>, flags: usize) -> Self {
+        PtyLock { pty, flags }
+    }
+}
+
+impl Resource for PtyLock {
+    fn pty(&self) -> Weak<RefCell<Pty>> {
+        self.pty.clone()
+    }
+
+    fn flags(&self) -> usize {
+        self.flags
+    }
+
+    fn path(&mut self, buf: &mut [u8]) -> Result<usize> {
+        if let Some(pty_lock) = self.pty.upgrade() {
+            pty_lock.borrow_mut().path(buf)
+        } else {
+            Err(Error::new(EPIPE))
+        }
+    }
+
+    // FIXME assuming c_int has same size as u32
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        if let Some(pty_lock) = self.pty.upgrade() {
+            let pty = pty_lock.borrow();
+
+            let lock_buf = buf
+                .get_mut(..4)
+                .and_then(|b| <&mut [u8; 4]>::try_from(b).ok())
+                .ok_or(Error::new(EBADF))?;
+            *lock_buf = (pty.locked as u32).to_ne_bytes();
+            Ok(4)
+        } else {
+            Ok(0)
+        }
+    }
+
+    fn write(&mut self, buf: &[u8]) -> Result<usize> {
+        if let Some(pty_lock) = self.pty.upgrade() {
+            let mut pty = pty_lock.borrow_mut();
+
+            let lock_val = u32::from_ne_bytes(
+                buf.get(..4)
+                    .and_then(|b| <[u8; 4]>::try_from(b).ok())
+                    .ok_or(Error::new(EBADF))?,
+            );
+            pty.locked = lock_val != 0;
+            Ok(4)
+        } else {
+            Ok(0)
+        }
+    }
+
+    fn sync(&mut self) -> Result<()> {
+        Ok(())
+    }
+
+    fn fcntl(&mut self, cmd: usize, arg: usize) -> Result<usize> {
+        match cmd {
+            F_GETFL => Ok(self.flags),
+            F_SETFL => {
+                self.flags = (self.flags & O_ACCMODE) | (arg & !O_ACCMODE);
+                Ok(0)
+            }
+            _ => Err(Error::new(EINVAL)),
+        }
+    }
+
+    fn fevent(&mut self) -> Result<EventFlags> {
+        Err(Error::new(EBADF))
+    }
+
+    fn events(&mut self) -> EventFlags {
+        EventFlags::empty()
+    }
+}

ptyd/src/ptname.rs

@@ -0,0 +1,83 @@
+use std::cell::RefCell;
+use std::rc::Weak;
+
+use syscall::error::{Error, Result, EBADF, EINVAL, EIO, EPIPE};
+use syscall::flag::{EventFlags, F_GETFL, F_SETFL, O_ACCMODE};
+
+use crate::pty::Pty;
+use crate::resource::Resource;
+
+/// Read side of a pipe
+pub struct PtsName {
+    pty: Weak<RefCell<Pty>>,
+    flags: usize,
+}
+
+impl PtsName {
+    pub fn new(pty: Weak<RefCell<Pty>>, flags: usize) -> Self {
+        PtsName { pty, flags }
+    }
+}
+
+impl Resource for PtsName {
+    fn pty(&self) -> Weak<RefCell<Pty>> {
+        self.pty.clone()
+    }
+
+    fn flags(&self) -> usize {
+        self.flags
+    }
+
+    fn path(&mut self, buf: &mut [u8]) -> Result<usize> {
+        if let Some(pty_lock) = self.pty.upgrade() {
+            pty_lock.borrow_mut().path(buf)
+        } else {
+            Err(Error::new(EPIPE))
+        }
+    }
+
+    fn read(&mut self, buf: &mut [u8]) -> Result<usize> {
+        if let Some(pty_lock) = self.pty.upgrade() {
+            let pty = pty_lock.borrow();
+            if pty.locked {
+                Err(Error::new(EIO))
+            } else {
+                let id_buf = buf
+                    .get_mut(..4)
+                    .and_then(|b| <&mut [u8; 4]>::try_from(b).ok())
+                    .ok_or(Error::new(EBADF))?;
+                *id_buf = (pty.id as u32).to_ne_bytes();
+                Ok(4)
+            }
+        } else {
+            Err(Error::new(EPIPE))
+        }
+    }
+
+    fn write(&mut self, _buf: &[u8]) -> Result<usize> {
+        Err(Error::new(EBADF))
+    }
+
+    fn sync(&mut self) -> Result<()> {
+        Ok(())
+    }
+
+    fn fcntl(&mut self, cmd: usize, arg: usize) -> Result<usize> {
+        match cmd {
+            F_GETFL => Ok(self.flags),
+            F_SETFL => {
+                self.flags = (self.flags & O_ACCMODE) | (arg & !O_ACCMODE);
+                Ok(0)
+            }
+            _ => Err(Error::new(EINVAL)),
+        }
+    }
+
+    fn fevent(&mut self) -> Result<EventFlags> {
+        Err(Error::new(EBADF))
+    }
+
+    fn events(&mut self) -> EventFlags {
+        EventFlags::empty()
+    }
+}

ptyd/src/pty.rs

@@ -7,6 +7,7 @@ use syscall::error::Result;
 pub struct Pty {
     pub id: usize,
     pub pgrp: usize,
+    pub locked: bool,
     pub termios: Termios,
     pub winsize: Winsize,
     pub cooked: Vec<u8>,
@@ -21,6 +22,7 @@ impl Pty {
         Pty {
             id,
             pgrp: 0,
+            locked: true,
             termios: Termios::default(),
             winsize: Winsize::default(),
             cooked: Vec::new(),

ptyd/src/scheme.rs

@@ -12,6 +12,8 @@ use syscall::schemev2::NewFdFlags;
 
 use crate::controlterm::PtyControlTerm;
 use crate::pgrp::PtyPgrp;
+use crate::ptlock::PtyLock;
+use crate::ptname::PtsName;
 use crate::pty::Pty;
 use crate::resource::Resource;
 use crate::subterm::PtySubTerm;
@@ -72,7 +74,12 @@ impl SchemeSync for PtyScheme {
         let id = self.next_id;
         self.next_id += 1;
 
+        // This happens if we are passed "/scheme/pty" and not "/scheme/pty/ptmx".
         if path.is_empty() {
+            return Err(Error::new(ENOENT));
+        }
+
+        if path == "ptmx" {
             let pty = Rc::new(RefCell::new(Pty::new(id)));
             self.handles.insert(
                 id,
@@ -119,6 +126,10 @@ impl SchemeSync for PtyScheme {
                 Box::new(PtyTermios::new(old_resource.pty(), old_resource.flags()))
             } else if buf == b"winsize" {
                 Box::new(PtyWinsize::new(old_resource.pty(), old_resource.flags()))
+            } else if buf == b"ptlock" {
+                Box::new(PtyLock::new(old_resource.pty(), old_resource.flags()))
+            } else if buf == b"ptsname" {
+                Box::new(PtsName::new(old_resource.pty(), old_resource.flags()))
             } else {
                 return Err(Error::new(EINVAL));
             }