Remove the shim kernel crate

kernel/src/syscall/tgkill.rs

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: MPL-2.0
+
+use super::SyscallReturn;
+use crate::{
+    prelude::*,
+    process::{
+        signal::{
+            sig_num::SigNum,
+            signals::user::{UserSignal, UserSignalKind},
+        },
+        tgkill, Pid,
+    },
+    thread::Tid,
+};
+
+/// tgkill send a signal to a thread with pid as its thread id, and tgid as its thread group id.
+pub fn sys_tgkill(tgid: Pid, tid: Tid, sig_num: u8, ctx: &Context) -> Result<SyscallReturn> {
+    let sig_num = if sig_num == 0 {
+        None
+    } else {
+        Some(SigNum::try_from(sig_num)?)
+    };
+
+    debug!("tgid = {}, pid = {}, sig_num = {:?}", tgid, tid, sig_num);
+
+    let signal = sig_num.map(|sig_num| {
+        let pid = ctx.process.pid();
+        let uid = ctx.posix_thread.credentials().ruid();
+        UserSignal::new(sig_num, UserSignalKind::Tkill, pid, uid)
+    });
+    tgkill(tid, tgid, signal)?;
+    Ok(SyscallReturn::Return(0))
+}