From 289fdbd7fdab8b6dd5c52c702e1d473f9ff481f6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?=
 <martin.kroening@eonerc.rwth-aachen.de>
Date: Thu, 16 Oct 2025 15:42:43 +0200
Subject: [PATCH] refactor: remove nightly feature `map_try_insert`

---
 src/executor/vsock.rs     | 18 ++++++++++-----
 src/lib.rs                |  1 -
 src/scheduler/mod.rs      | 22 ++++++++++--------
 src/scheduler/task/mod.rs | 48 ++++++++++-----------------------------
 4 files changed, 37 insertions(+), 52 deletions(-)

diff --git a/src/executor/vsock.rs b/src/executor/vsock.rs
index c635ae10aa..740af43e5f 100644
--- a/src/executor/vsock.rs
+++ b/src/executor/vsock.rs
@@ -1,4 +1,4 @@
-use alloc::collections::BTreeMap;
+use alloc::collections::{BTreeMap, btree_map};
 use alloc::vec::Vec;
 use core::future;
 use core::task::Poll;
@@ -170,10 +170,15 @@ impl VsockMap {
 	}
 
 	pub fn bind(&mut self, port: u32) -> io::Result<()> {
-		self.port_map
-			.try_insert(port, RawSocket::new(VsockState::Listen))
-			.map_err(|_| Errno::Addrinuse)?;
-		Ok(())
+		let entry = self.port_map.entry(port);
+
+		match entry {
+			btree_map::Entry::Vacant(vacant_entry) => {
+				vacant_entry.insert(RawSocket::new(VsockState::Listen));
+				Ok(())
+			}
+			btree_map::Entry::Occupied(_occupied_entry) => Err(Errno::Addrinuse),
+		}
 	}
 
 	pub fn connect(&mut self, port: u32, cid: u32) -> io::Result<u32> {
@@ -182,7 +187,8 @@ impl VsockMap {
 			raw.remote_cid = cid;
 			raw.remote_port = port;
 
-			if self.port_map.try_insert(i, raw).is_ok() {
+			if let btree_map::Entry::Vacant(vacant_entry) = self.port_map.entry(i) {
+				vacant_entry.insert(raw);
 				return Ok(i);
 			}
 		}
diff --git a/src/lib.rs b/src/lib.rs
index 326d7db3ba..4a203ce562 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -11,7 +11,6 @@
 #![feature(allocator_api)]
 #![feature(linkage)]
 #![feature(linked_list_cursors)]
-#![feature(map_try_insert)]
 #![feature(maybe_uninit_as_bytes)]
 #![feature(maybe_uninit_slice)]
 #![feature(maybe_uninit_write_slice)]
diff --git a/src/scheduler/mod.rs b/src/scheduler/mod.rs
index 0196ea7b2f..3732e27b18 100644
--- a/src/scheduler/mod.rs
+++ b/src/scheduler/mod.rs
@@ -14,7 +14,7 @@ use core::sync::atomic::{AtomicI32, AtomicU32, Ordering};
 
 use ahash::RandomState;
 use crossbeam_utils::Backoff;
-use hashbrown::HashMap;
+use hashbrown::{HashMap, hash_map};
 use hermit_sync::*;
 #[cfg(target_arch = "riscv64")]
 use riscv::register::sstatus;
@@ -564,10 +564,12 @@ impl PerCoreScheduler {
 			};
 
 			let fd = new_fd()?;
-			if object_map.try_insert(fd, obj).is_err() {
-				Err(Errno::Mfile)
-			} else {
-				Ok(fd)
+			match object_map.entry(fd) {
+				hash_map::Entry::Occupied(_occupied_entry) => Err(Errno::Mfile),
+				hash_map::Entry::Vacant(vacant_entry) => {
+					vacant_entry.insert(obj);
+					Ok(fd)
+				}
 			}
 		})
 	}
@@ -583,10 +585,12 @@ impl PerCoreScheduler {
 
 			let obj = object_map.get(&fd1).cloned().ok_or(Errno::Badf)?;
 
-			if object_map.try_insert(fd2, obj).is_err() {
-				Err(Errno::Mfile)
-			} else {
-				Ok(fd2)
+			match object_map.entry(fd2) {
+				hash_map::Entry::Occupied(_occupied_entry) => Err(Errno::Mfile),
+				hash_map::Entry::Vacant(vacant_entry) => {
+					vacant_entry.insert(obj);
+					Ok(fd2)
+				}
 			}
 		})
 	}
diff --git a/src/scheduler/task/mod.rs b/src/scheduler/task/mod.rs
index 98484c13c5..dfca1377fe 100644
--- a/src/scheduler/task/mod.rs
+++ b/src/scheduler/task/mod.rs
@@ -468,43 +468,19 @@ impl Task {
 			let objmap = OBJECT_MAP.get().unwrap().clone();
 			let mut guard = objmap.write();
 			if env::is_uhyve() {
-				guard
-					.try_insert(
-						STDIN_FILENO,
-						Arc::new(async_lock::RwLock::new(UhyveStdin::new())),
-					)
-					.expect("cannot insert stdin");
-				guard
-					.try_insert(
-						STDOUT_FILENO,
-						Arc::new(async_lock::RwLock::new(UhyveStdout::new())),
-					)
-					.expect("cannot insert stdout");
-				guard
-					.try_insert(
-						STDERR_FILENO,
-						Arc::new(async_lock::RwLock::new(UhyveStderr::new())),
-					)
-					.expect("cannot insert stderr");
+				let stdin = Arc::new(async_lock::RwLock::new(UhyveStdin::new()));
+				let stdout = Arc::new(async_lock::RwLock::new(UhyveStdout::new()));
+				let stderr = Arc::new(async_lock::RwLock::new(UhyveStderr::new()));
+				guard.insert(STDIN_FILENO, stdin);
+				guard.insert(STDOUT_FILENO, stdout);
+				guard.insert(STDERR_FILENO, stderr);
 			} else {
-				guard
-					.try_insert(
-						STDIN_FILENO,
-						Arc::new(async_lock::RwLock::new(GenericStdin::new())),
-					)
-					.expect("cannot insert stdin");
-				guard
-					.try_insert(
-						STDOUT_FILENO,
-						Arc::new(async_lock::RwLock::new(GenericStdout::new())),
-					)
-					.expect("cannot insert stdout");
-				guard
-					.try_insert(
-						STDERR_FILENO,
-						Arc::new(async_lock::RwLock::new(GenericStderr::new())),
-					)
-					.expect("cannot insert stderr");
+				let stdin = Arc::new(async_lock::RwLock::new(GenericStdin::new()));
+				let stdout = Arc::new(async_lock::RwLock::new(GenericStdout::new()));
+				let stderr = Arc::new(async_lock::RwLock::new(GenericStderr::new()));
+				guard.insert(STDIN_FILENO, stdin);
+				guard.insert(STDOUT_FILENO, stdout);
+				guard.insert(STDERR_FILENO, stderr);
 			}
 		}