From c3629a65e73153f50f0912291c6fd6d61b5ffbbd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?=
 <martin.kroening@eonerc.rwth-aachen.de>
Date: Mon, 13 Oct 2025 09:32:51 +0200
Subject: [PATCH] feat(syscalls): remove condvar module

---
 src/syscalls/condvar.rs | 153 ----------------------------------------
 src/syscalls/mod.rs     |   2 -
 2 files changed, 155 deletions(-)
 delete mode 100644 src/syscalls/condvar.rs

diff --git a/src/syscalls/condvar.rs b/src/syscalls/condvar.rs
deleted file mode 100644
index aefff063f8..0000000000
--- a/src/syscalls/condvar.rs
+++ /dev/null
@@ -1,153 +0,0 @@
-// The implementation is inspired by Andrew D. Birrell's paper
-// "Implementing Condition Variables with Semaphores"
-
-use alloc::boxed::Box;
-use core::sync::atomic::{AtomicIsize, Ordering};
-use core::{mem, ptr};
-
-use crate::synch::semaphore::Semaphore;
-
-struct CondQueue {
-	counter: AtomicIsize,
-	sem1: Semaphore,
-	sem2: Semaphore,
-}
-
-impl CondQueue {
-	pub fn new() -> Self {
-		CondQueue {
-			counter: AtomicIsize::new(0),
-			sem1: Semaphore::new(0),
-			sem2: Semaphore::new(0),
-		}
-	}
-}
-
-#[hermit_macro::system]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn sys_destroy_queue(ptr: usize) -> i32 {
-	unsafe {
-		let id = ptr::with_exposed_provenance_mut::<usize>(ptr);
-		if id.is_null() {
-			debug!("sys_wait: invalid address to condition variable");
-			return -1;
-		}
-
-		if *id != 0 {
-			let cond = Box::from_raw(ptr::with_exposed_provenance_mut::<CondQueue>(*id));
-			mem::drop(cond);
-		}
-
-		0
-	}
-}
-
-#[hermit_macro::system]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn sys_notify(ptr: usize, count: i32) -> i32 {
-	unsafe {
-		let id = ptr::with_exposed_provenance::<usize>(ptr);
-
-		if id.is_null() {
-			// invalid argument
-			debug!("sys_notify: invalid address to condition variable");
-			return -1;
-		}
-
-		if *id == 0 {
-			debug!("sys_notify: invalid reference to condition variable");
-			return -1;
-		}
-
-		let cond = &mut *(ptr::with_exposed_provenance_mut::<CondQueue>(*id));
-
-		if count < 0 {
-			// Wake up all task that has been waiting for this condition variable
-			while cond.counter.load(Ordering::SeqCst) > 0 {
-				cond.counter.fetch_sub(1, Ordering::SeqCst);
-				cond.sem1.release();
-				cond.sem2.acquire(None);
-			}
-		} else {
-			for _ in 0..count {
-				cond.counter.fetch_sub(1, Ordering::SeqCst);
-				cond.sem1.release();
-				cond.sem2.acquire(None);
-			}
-		}
-
-		0
-	}
-}
-
-#[hermit_macro::system]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn sys_init_queue(ptr: usize) -> i32 {
-	unsafe {
-		let id = ptr::with_exposed_provenance_mut::<usize>(ptr);
-		if id.is_null() {
-			debug!("sys_init_queue: invalid address to condition variable");
-			return -1;
-		}
-
-		if *id == 0 {
-			debug!("Create condition variable queue");
-			let queue = Box::new(CondQueue::new());
-			*id = Box::into_raw(queue) as usize;
-		}
-
-		0
-	}
-}
-
-#[hermit_macro::system]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn sys_add_queue(ptr: usize, timeout_ns: i64) -> i32 {
-	unsafe {
-		let id = ptr::with_exposed_provenance_mut::<usize>(ptr);
-		if id.is_null() {
-			debug!("sys_add_queue: invalid address to condition variable");
-			return -1;
-		}
-
-		if *id == 0 {
-			debug!("Create condition variable queue");
-			let queue = Box::new(CondQueue::new());
-			*id = Box::into_raw(queue) as usize;
-		}
-
-		if timeout_ns <= 0 {
-			let cond = &mut *(ptr::with_exposed_provenance_mut::<CondQueue>(*id));
-			cond.counter.fetch_add(1, Ordering::SeqCst);
-
-			0
-		} else {
-			error!("Conditional variables with timeout is currently not supported");
-
-			-1
-		}
-	}
-}
-
-#[hermit_macro::system]
-#[unsafe(no_mangle)]
-pub unsafe extern "C" fn sys_wait(ptr: usize) -> i32 {
-	unsafe {
-		let id = ptr::with_exposed_provenance_mut::<usize>(ptr);
-		if id.is_null() {
-			debug!("sys_wait: invalid address to condition variable");
-			return -1;
-		}
-
-		if *id == 0 {
-			error!("sys_wait: Unable to determine condition variable");
-			return -1;
-		}
-
-		let cond = &mut *(ptr::with_exposed_provenance_mut::<CondQueue>(*id));
-		cond.sem1.acquire(None);
-		cond.sem2.release();
-
-		0
-	}
-}
diff --git a/src/syscalls/mod.rs b/src/syscalls/mod.rs
index fc3fa592ef..bebab528cd 100644
--- a/src/syscalls/mod.rs
+++ b/src/syscalls/mod.rs
@@ -10,7 +10,6 @@ use core::ptr::null;
 use dirent_display::Dirent64Display;
 use hermit_sync::Lazy;
 
-pub use self::condvar::*;
 pub use self::entropy::*;
 pub use self::futex::*;
 pub use self::processor::*;
@@ -33,7 +32,6 @@ use crate::fs::{self, FileAttr, SeekWhence};
 use crate::mm::ALLOCATOR;
 use crate::syscalls::interfaces::SyscallInterface;
 
-mod condvar;
 mod entropy;
 mod futex;
 pub(crate) mod interfaces;