From ca67da16e665e088cc1acf8bef1599a6e641e1c2 Mon Sep 17 00:00:00 2001
From: Drew Galbraith <dgalbraith33@gmail.com>
Date: Sun, 28 Jul 2024 19:48:05 -0700
Subject: [PATCH] [Mammoth] Move thread syscalls to wrappers.

---
 rust/lib/mammoth/src/syscall.rs | 37 ++++++++++++++++++++++++++-
 rust/lib/mammoth/src/thread.rs  | 44 ++++++++++-----------------------
 rust/usr/testbed/src/main.rs    | 16 ++----------
 3 files changed, 51 insertions(+), 46 deletions(-)

diff --git a/rust/lib/mammoth/src/syscall.rs b/rust/lib/mammoth/src/syscall.rs
index d46bea0..aa0fc5b 100644
--- a/rust/lib/mammoth/src/syscall.rs
+++ b/rust/lib/mammoth/src/syscall.rs
@@ -1,11 +1,13 @@
 extern crate alloc;
 
 use crate::zion;
+use crate::zion::z_cap_t;
+use crate::zion::ZError;
 use core::ffi::c_void;
 use core::panic::PanicInfo;
 
 #[must_use]
-pub fn syscall<T>(id: u64, req: &T) -> Result<(), zion::ZError> {
+pub fn syscall<T>(id: u64, req: &T) -> Result<(), ZError> {
     unsafe {
         let resp = zion::SysCall1(id, req as *const T as *const c_void);
         if resp != 0 {
@@ -37,3 +39,36 @@ pub fn debug(msg: &str) {
     };
     syscall(zion::kZionDebug, &req).expect("Failed to write");
 }
+
+pub fn thread_create(proc_cap: z_cap_t) -> Result<z_cap_t, ZError> {
+    let mut cap = 0;
+    syscall(
+        zion::kZionThreadCreate,
+        &zion::ZThreadCreateReq {
+            proc_cap,
+            thread_cap: &mut cap as *mut z_cap_t,
+        },
+    )?;
+    Ok(cap)
+}
+
+pub fn thread_start(thread_cap: z_cap_t, entry: u64, arg1: u64, arg2: u64) -> Result<(), ZError> {
+    syscall(
+        zion::kZionThreadStart,
+        &zion::ZThreadStartReq {
+            thread_cap,
+            entry,
+            arg1,
+            arg2,
+        },
+    )
+}
+
+pub fn thread_wait(thread_cap: z_cap_t) -> Result<(), ZError> {
+    syscall(zion::kZionThreadWait, &zion::ZThreadWaitReq { thread_cap })
+}
+
+pub fn thread_exit() -> ! {
+    let _ = syscall(zion::kZionThreadExit, &zion::ZThreadExitReq {});
+    unreachable!();
+}
diff --git a/rust/lib/mammoth/src/thread.rs b/rust/lib/mammoth/src/thread.rs
index d596c20..1ddc85d 100644
--- a/rust/lib/mammoth/src/thread.rs
+++ b/rust/lib/mammoth/src/thread.rs
@@ -7,17 +7,13 @@ use core::ffi::c_void;
 pub type ThreadEntry = fn(*const c_void) -> ();
 
 #[no_mangle]
-extern "C" fn entry_point(entry_ptr: *const ThreadEntry, arg1: *const c_void) -> ! {
-    debug!("Entry {:#p} arg1 {:#x}", entry_ptr, arg1 as u64);
+extern "C" fn internal_entry_point(entry_ptr: *const ThreadEntry, arg1: *const c_void) -> ! {
     let entry = unsafe { *entry_ptr };
 
     entry(arg1);
 
-    let _ = syscall::syscall(zion::kZionThreadExit, &zion::ZThreadExitReq {});
-
-    unreachable!();
+    syscall::thread_exit()
 }
-
 // TODO: Add a Drop implementation that kills this thread and drops its capability.
 pub struct Thread<'a> {
     cap: z_cap_t,
@@ -27,35 +23,21 @@ pub struct Thread<'a> {
 }
 
 impl<'a> Thread<'a> {
-    pub fn spawn(entry: &'a ThreadEntry, arg1: *const c_void) -> Self {
-        let mut cap: z_cap_t = 0;
-        let req = zion::ZThreadCreateReq {
-            proc_cap: unsafe { crate::init::SELF_PROC_CAP },
-            thread_cap: &mut cap as *mut z_cap_t,
-        };
+    pub fn spawn(entry: &'a ThreadEntry, arg1: *const c_void) -> Result<Self, zion::ZError> {
+        let proc_cap = unsafe { crate::init::SELF_PROC_CAP };
+        let cap = syscall::thread_create(proc_cap)?;
 
-        syscall::syscall(zion::kZionThreadCreate, &req).expect("Failed to create thread.");
+        syscall::thread_start(
+            cap,
+            internal_entry_point as u64,
+            entry as *const ThreadEntry as u64,
+            arg1 as u64,
+        )?;
 
-        syscall::syscall(
-            zion::kZionThreadStart,
-            &zion::ZThreadStartReq {
-                thread_cap: cap,
-                entry: entry_point as u64,
-                arg1: entry as *const ThreadEntry as u64,
-                arg2: arg1 as u64,
-            },
-        )
-        .expect("Failed to start thread.");
-
-        Self { cap, _entry: entry }
+        Ok(Self { cap, _entry: entry })
     }
 
     pub fn join(&self) -> Result<(), zion::ZError> {
-        syscall::syscall(
-            zion::kZionThreadWait,
-            &zion::ZThreadWaitReq {
-                thread_cap: self.cap,
-            },
-        )
+        syscall::thread_wait(self.cap)
     }
 }
diff --git a/rust/usr/testbed/src/main.rs b/rust/usr/testbed/src/main.rs
index b612523..661c98b 100644
--- a/rust/usr/testbed/src/main.rs
+++ b/rust/usr/testbed/src/main.rs
@@ -3,11 +3,9 @@
 
 extern crate alloc;
 
-use alloc::boxed::Box;
 use alloc::string::ToString;
 use mammoth::debug;
 use mammoth::define_entry;
-use mammoth::syscall::debug;
 use mammoth::thread;
 use mammoth::zion::z_err_t;
 use yellowstone::GetEndpointRequest;
@@ -17,17 +15,7 @@ define_entry!();
 
 #[no_mangle]
 pub extern "C" fn main() -> z_err_t {
-    debug("Testing!");
-    let x = Box::new("Heap str");
-    debug(&x);
-    debug!("Formatted {}", "string");
-    let mut vmmo_cap: u64 = 0;
-    let obj_req = mammoth::zion::ZMemoryObjectCreateReq {
-        size: 0,
-        vmmo_cap: &mut vmmo_cap as *mut u64,
-    };
-    mammoth::syscall::syscall(mammoth::zion::kZionMemoryObjectCreate, &obj_req)
-        .expect("Failed to create memory object");
+    debug!("Testing!");
 
     let mut yellowstone;
     unsafe {
@@ -45,7 +33,7 @@ pub extern "C" fn main() -> z_err_t {
     let e: thread::ThreadEntry = |_| {
         debug!("Testing 1 2 3");
     };
-    let t = thread::Thread::spawn(&e, core::ptr::null());
+    let t = thread::Thread::spawn(&e, core::ptr::null()).expect("Failed to spawn thread");
 
     t.join().expect("Failed to wait.");