Introduce IpcReceiverWIthContext and move ipc stuff to common/ipc.rs

Fall back to /tmp/zellij-{uid} directory if runtime_dir is not available.
Use serialize_into() to avoid Vec allocation.
And some cleanup

5 files changed, 121 insertions, 82 deletions

diff --git a/src/common/ipc.rs b/src/common/ipc.rs
index 68aa676b..190680dc 100644
--- a/src/common/ipc.rs
+++ b/src/common/ipc.rs
@@ -1,7 +1,13 @@
 //! IPC stuff for starting to split things into a client and server model.
 
+use crate::common::errors::{get_current_ctx, ErrorContext};
+use interprocess::local_socket::LocalSocketStream;
+use nix::unistd::dup;
 use serde::{Deserialize, Serialize};
 use std::collections::HashSet;
+use std::io::{self, Write};
+use std::marker::PhantomData;
+use std::os::unix::io::{AsRawFd, FromRawFd};
 
 type SessionId = u64;
 
@@ -45,3 +51,69 @@ pub enum _ServerToClientMsg {
     // A list of sessions
     SessionList(HashSet<Session>),
 }
+
+/// Sends messages on a stream socket, along with an [`ErrorContext`].
+pub struct IpcSenderWithContext<T: Serialize> {
+    sender: io::BufWriter<LocalSocketStream>,
+    _phantom: PhantomData<T>,
+}
+
+impl<T: Serialize> IpcSenderWithContext<T> {
+    /// Returns a sender to the given [LocalSocketStream](interprocess::local_socket::LocalSocketStream).
+    pub fn new(sender: LocalSocketStream) -> Self {
+        Self {
+            sender: io::BufWriter::new(sender),
+            _phantom: PhantomData,
+        }
+    }
+
+    /// Sends an event, along with the current [`ErrorContext`], on this [`IpcSenderWithContext`]'s socket.
+    pub fn send(&mut self, msg: T) {
+        let err_ctx = get_current_ctx();
+        bincode::serialize_into(&mut self.sender, &(msg, err_ctx)).unwrap();
+        self.sender.flush().unwrap();
+    }
+
+    /// Returns an [`IpcReceiverWithContext`] with the same socket as this sender.
+    pub fn get_receiver<F>(&self) -> IpcReceiverWithContext<F>
+    where
+        F: for<'de> Deserialize<'de> + Serialize,
+    {
+        let sock_fd = self.sender.get_ref().as_raw_fd();
+        let dup_sock = dup(sock_fd).unwrap();
+        let socket = unsafe { LocalSocketStream::from_raw_fd(dup_sock) };
+        IpcReceiverWithContext::new(socket)
+    }
+}
+
+/// Receives messages on a stream socket, along with an [`ErrorContext`].
+pub struct IpcReceiverWithContext<T> {
+    receiver: io::BufReader<LocalSocketStream>,
+    _phantom: PhantomData<T>,
+}
+
+impl<T> IpcReceiverWithContext<T>
+where
+    T: for<'de> Deserialize<'de> + Serialize,
+{
+    /// Returns a receiver to the given [LocalSocketStream](interprocess::local_socket::LocalSocketStream).
+    pub fn new(receiver: LocalSocketStream) -> Self {
+        Self {
+            receiver: io::BufReader::new(receiver),
+            _phantom: PhantomData,
+        }
+    }
+
+    /// Receives an event, along with the current [`ErrorContext`], on this [`IpcReceiverWithContext`]'s socket.
+    pub fn recv(&mut self) -> (T, ErrorContext) {
+        bincode::deserialize_from(&mut self.receiver).unwrap()
+    }
+
+    /// Returns an [`IpcSenderWithContext`] with the same socket as this receiver.
+    pub fn get_sender<F: Serialize>(&self) -> IpcSenderWithContext<F> {
+        let sock_fd = self.receiver.get_ref().as_raw_fd();
+        let dup_sock = dup(sock_fd).unwrap();
+        let socket = unsafe { LocalSocketStream::from_raw_fd(dup_sock) };
+        IpcSenderWithContext::new(socket)
+    }
+}
diff --git a/src/common/mod.rs b/src/common/mod.rs
index bf4c3ae6..6061f1a6 100644
--- a/src/common/mod.rs
+++ b/src/common/mod.rs
@@ -12,11 +12,8 @@ pub mod wasm_vm;
 use crate::panes::PaneId;
 use crate::server::ServerInstruction;
 use async_std::task_local;
-use directories_next::ProjectDirs;
 use errors::{get_current_ctx, ErrorContext};
-use lazy_static::lazy_static;
 use std::cell::RefCell;
-use std::path::PathBuf;
 use std::sync::mpsc;
 
 /// An [MPSC](mpsc) asynchronous channel with added error context.
@@ -76,15 +73,3 @@ task_local! {
     /// stack in the form of an [`ErrorContext`].
     static ASYNCOPENCALLS: RefCell<ErrorContext> = RefCell::default()
 }
-
-lazy_static! {
-    pub static ref ZELLIJ_IPC_PIPE: PathBuf = {
-        let project_dir = ProjectDirs::from("org", "Zellij Contributors", "Zellij").unwrap();
-        let ipc_dir = project_dir
-            .runtime_dir()
-            .unwrap_or_else(|| project_dir.cache_dir());
-        std::fs::create_dir_all(ipc_dir).unwrap();
-        let session_name = names::Generator::default().next().unwrap();
-        ipc_dir.join(session_name)
-    };
-}
diff --git a/src/common/os_input_output.rs b/src/common/os_input_output.rs
index 9a124011..a339b08d 100644
--- a/src/common/os_input_output.rs
+++ b/src/common/os_input_output.rs
@@ -5,20 +5,21 @@ use nix::sys::signal::{kill, Signal};
 use nix::sys::termios;
 use nix::sys::wait::waitpid;
 use nix::unistd::{self, ForkResult, Pid};
-use serde::Serialize;
 use signal_hook::{consts::signal::*, iterator::Signals};
 use std::env;
 use std::io;
 use std::io::prelude::*;
-use std::marker::PhantomData;
-use std::os::unix::io::{AsRawFd, FromRawFd, RawFd};
+use std::os::unix::io::RawFd;
 use std::path::PathBuf;
 use std::process::{Child, Command};
 use std::sync::{Arc, Mutex};
 
 use crate::client::ClientInstruction;
-use crate::common::ZELLIJ_IPC_PIPE;
-use crate::errors::{get_current_ctx, ErrorContext};
+use crate::common::{
+    ipc::{IpcReceiverWithContext, IpcSenderWithContext},
+    utils::consts::ZELLIJ_IPC_PIPE,
+};
+use crate::errors::ErrorContext;
 use crate::panes::PositionAndSize;
 use crate::server::ServerInstruction;
 
@@ -158,35 +159,10 @@ fn spawn_terminal(file_to_open: Option<PathBuf>, orig_termios: termios::Termios)
     (pid_primary, pid_secondary)
 }
 
-/// Sends messages on an [ipmpsc](ipmpsc) channel, along with an [`ErrorContext`].
-struct IpcSenderWithContext<T: Serialize> {
-    sender: io::BufWriter<LocalSocketStream>,
-    _phantom: PhantomData<T>,
-}
-
-impl<T: Serialize> IpcSenderWithContext<T> {
-    /// Returns a sender to the given [SharedRingBuffer](ipmpsc::SharedRingBuffer).
-    fn new(sender: LocalSocketStream) -> Self {
-        Self {
-            sender: io::BufWriter::new(sender),
-            _phantom: PhantomData,
-        }
-    }
-
-    /// Sends an event, along with the current [`ErrorContext`], on this
-    /// [`IpcSenderWithContext`]'s channel.
-    fn send(&mut self, msg: T) -> Result<(), std::io::Error> {
-        let err_ctx = get_current_ctx();
-        self.sender
-            .write_all(&bincode::serialize(&(msg, err_ctx)).unwrap())?;
-        self.sender.flush()
-    }
-}
-
 #[derive(Clone)]
 pub struct ServerOsInputOutput {
     orig_termios: Arc<Mutex<termios::Termios>>,
-    receive_instructions_from_client: Option<Arc<Mutex<io::BufReader<LocalSocketStream>>>>,
+    receive_instructions_from_client: Option<Arc<Mutex<IpcReceiverWithContext<ServerInstruction>>>>,
     send_instructions_to_client: Arc<Mutex<Option<IpcSenderWithContext<ClientInstruction>>>>,
 }
 
@@ -252,15 +228,12 @@ impl ServerOsApi for ServerOsInputOutput {
         Ok(())
     }
     fn recv_from_client(&self) -> (ServerInstruction, ErrorContext) {
-        bincode::deserialize_from(
-            &mut *self
-                .receive_instructions_from_client
-                .as_ref()
-                .unwrap()
-                .lock()
-                .unwrap(),
-        )
-        .unwrap()
+        self.receive_instructions_from_client
+            .as_ref()
+            .unwrap()
+            .lock()
+            .unwrap()
+            .recv()
     }
     fn send_to_client(&self, msg: ClientInstruction) {
         self.send_instructions_to_client
@@ -268,27 +241,22 @@ impl ServerOsApi for ServerOsInputOutput {
             .unwrap()
             .as_mut()
             .unwrap()
-            .send(msg)
-            .unwrap();
+            .send(msg);
     }
     fn add_client_sender(&mut self) {
         assert!(self.send_instructions_to_client.lock().unwrap().is_none());
-        let sock_fd = self
+        let sender = self
             .receive_instructions_from_client
             .as_ref()
             .unwrap()
             .lock()
             .unwrap()
-            .get_ref()
-            .as_raw_fd();
-        let dup_fd = unistd::dup(sock_fd).unwrap();
-        let dup_sock = unsafe { LocalSocketStream::from_raw_fd(dup_fd) };
-        *self.send_instructions_to_client.lock().unwrap() =
-            Some(IpcSenderWithContext::new(dup_sock));
+            .get_sender();
+        *self.send_instructions_to_client.lock().unwrap() = Some(sender);
     }
     fn update_receiver(&mut self, stream: LocalSocketStream) {
         self.receive_instructions_from_client =
-            Some(Arc::new(Mutex::new(io::BufReader::new(stream))));
+            Some(Arc::new(Mutex::new(IpcReceiverWithContext::new(stream))));
     }
 }
 
@@ -312,7 +280,7 @@ pub fn get_server_os_input() -> ServerOsInputOutput {
 pub struct ClientOsInputOutput {
     orig_termios: Arc<Mutex<termios::Termios>>,
     send_instructions_to_server: Arc<Mutex<Option<IpcSenderWithContext<ServerInstruction>>>>,
-    receive_instructions_from_server: Arc<Mutex<Option<io::BufReader<LocalSocketStream>>>>,
+    receive_instructions_from_server: Arc<Mutex<Option<IpcReceiverWithContext<ClientInstruction>>>>,
 }
 
 /// The `ClientOsApi` trait represents an abstract interface to the features of an operating system that
@@ -375,19 +343,15 @@ impl ClientOsApi for ClientOsInputOutput {
             .unwrap()
             .as_mut()
             .unwrap()
-            .send(msg)
-            .unwrap();
+            .send(msg);
     }
     fn recv_from_server(&self) -> (ClientInstruction, ErrorContext) {
-        bincode::deserialize_from(
-            &mut self
-                .receive_instructions_from_server
-                .lock()
-                .unwrap()
-                .as_mut()
-                .unwrap(),
-        )
-        .unwrap()
+        self.receive_instructions_from_server
+            .lock()
+            .unwrap()
+            .as_mut()
+            .unwrap()
+            .recv()
     }
     fn receive_sigwinch(&self, cb: Box<dyn Fn()>) {
         let mut signals = Signals::new(&[SIGWINCH, SIGTERM, SIGINT, SIGQUIT]).unwrap();
@@ -411,12 +375,10 @@ impl ClientOsApi for ClientOsInputOutput {
                 LocalSocketStream::connect(ZELLIJ_IPC_PIPE.clone()).unwrap()
             }
         };
-        let sock_fd = socket.as_raw_fd();
-        let dup_fd = unistd::dup(sock_fd).unwrap();
-        let receiver = unsafe { LocalSocketStream::from_raw_fd(dup_fd) };
         let sender = IpcSenderWithContext::new(socket);
+        let receiver = sender.get_receiver();
         *self.send_instructions_to_server.lock().unwrap() = Some(sender);
-        *self.receive_instructions_from_server.lock().unwrap() = Some(io::BufReader::new(receiver));
+        *self.receive_instructions_from_server.lock().unwrap() = Some(receiver);
     }
 }
 
diff --git a/src/common/utils/consts.rs b/src/common/utils/consts.rs
index f031dd38..c21e3029 100644
--- a/src/common/utils/consts.rs
+++ b/src/common/utils/consts.rs
@@ -1,5 +1,25 @@
 //! Zellij program-wide constants.
 
+use directories_next::ProjectDirs;
+use lazy_static::lazy_static;
+use nix::unistd::Uid;
+use std::path::PathBuf;
+
 pub const ZELLIJ_TMP_DIR: &str = "/tmp/zellij";
 pub const ZELLIJ_TMP_LOG_DIR: &str = "/tmp/zellij/zellij-log";
 pub const ZELLIJ_TMP_LOG_FILE: &str = "/tmp/zellij/zellij-log/log.txt";
+
+lazy_static! {
+    static ref UID: Uid = Uid::current();
+    pub static ref SESSION_NAME: String = names::Generator::default().next().unwrap();
+    pub static ref ZELLIJ_IPC_PIPE: PathBuf = {
+        let project_dir = ProjectDirs::from("org", "Zellij Contributors", "Zellij").unwrap();
+        let mut ipc_dir = project_dir
+            .runtime_dir()
+            .map(|p| p.to_owned())
+            .unwrap_or_else(|| PathBuf::from("/tmp/zellij-".to_string() + &format!("{}", *UID)));
+        std::fs::create_dir_all(&ipc_dir).unwrap();
+        ipc_dir.push(&*SESSION_NAME);
+        ipc_dir
+    };
+}
diff --git a/src/server/mod.rs b/src/server/mod.rs
index c1f93d5b..25a95222 100644
--- a/src/server/mod.rs
+++ b/src/server/mod.rs
@@ -16,7 +16,6 @@ use zellij_tile::data::{Event, EventType, ModeInfo};
 
 use crate::cli::CliArgs;
 use crate::client::ClientInstruction;
-use crate::common::ZELLIJ_IPC_PIPE;
 use crate::common::{
     errors::{ContextType, PluginContext, PtyContext, ScreenContext, ServerContext},
     input::actions::{Action, Direction},
@@ -24,6 +23,7 @@ use crate::common::{
     os_input_output::ServerOsApi,
     pty_bus::{PtyBus, PtyInstruction},
     screen::{Screen, ScreenInstruction},
+    utils::consts::ZELLIJ_IPC_PIPE,
     wasm_vm::{wasi_stdout, wasi_write_string, zellij_imports, PluginEnv, PluginInstruction},
     ChannelWithContext, SenderType, SenderWithContext,
 };