From bc22846ab31bd2eaf7adecee8de258363b5a71d7 Mon Sep 17 00:00:00 2001
From: Mark Poliakov <mark@alnyan.me>
Date: Thu, 16 Nov 2023 16:10:02 +0200
Subject: [PATCH] alnyan/yggdrasil: better argument passing from kernel

---
 library/std/src/sys/yggdrasil/args.rs | 21 ++++---------
 library/std/src/sys/yggdrasil/mod.rs  | 22 +++++--------
 library/std/src/sys/yggdrasil/os.rs   |  1 -
 library/std/src/sys/yggdrasil/util.rs | 45 ---------------------------
 yggdrasil-rt                          |  2 +-
 5 files changed, 14 insertions(+), 77 deletions(-)

diff --git a/library/std/src/sys/yggdrasil/args.rs b/library/std/src/sys/yggdrasil/args.rs
index a2ec41efdec..01f594ec1f1 100644
--- a/library/std/src/sys/yggdrasil/args.rs
+++ b/library/std/src/sys/yggdrasil/args.rs
@@ -2,17 +2,15 @@ use crate::ffi::OsString;
 use crate::fmt;
 use crate::mem::size_of;
 use crate::str::FromStr;
-use crate::sys::yggdrasil::util::KStringList;
 
 #[allow(dead_code)]
-#[derive(Clone, Copy)]
+#[derive(Clone)]
 pub struct Args {
-    list: KStringList,
-    index: usize,
+    iter: crate::slice::Iter<'static, &'static str>,
 }
 
 pub fn args() -> Args {
-    Args { list: unsafe { KStringList::new(super::ARGS) }, index: 0 }
+    unsafe { Args { iter: super::ARGS.assume_init_ref().iter() } }
 }
 
 impl fmt::Debug for Args {
@@ -25,22 +23,15 @@ impl Iterator for Args {
     type Item = OsString;
 
     fn next(&mut self) -> Option<Self::Item> {
-        if self.index == self.list.len() {
-            return None;
-        }
-
-        let str = self.list.get(self.index);
-        self.index += 1;
-
-        let os_str = OsString::from_str(str).unwrap();
-
+        let item = self.iter.next()?;
+        let os_str = OsString::from_str(item).unwrap();
         Some(os_str)
     }
 }
 
 impl ExactSizeIterator for Args {
     fn len(&self) -> usize {
-        self.list.len()
+        self.iter.len()
     }
 }
 
diff --git a/library/std/src/sys/yggdrasil/mod.rs b/library/std/src/sys/yggdrasil/mod.rs
index d181bd052d7..ad868a22d7f 100644
--- a/library/std/src/sys/yggdrasil/mod.rs
+++ b/library/std/src/sys/yggdrasil/mod.rs
@@ -37,7 +37,7 @@ pub(self) use yggdrasil_rt;
 
 mod util;
 
-use yggdrasil_rt::process::ExitCode as OsExitCode;
+use yggdrasil_rt::process::{ExitCode as OsExitCode, ProgramArgumentInner};
 use yggdrasil_rt::Error as OsError;
 
 use crate::path::Path;
@@ -46,8 +46,9 @@ use crate::path::Path;
 //
 // 0x000: args pointer
 // 0x008: envs pointer
-static mut ARGS: usize = 0;
+// static mut ARGS: usize = 0;
 // TODO handle this in better way
+static mut ARGS: MaybeUninit<&'static [&'static str]> = MaybeUninit::uninit();
 static mut ENVS: MaybeUninit<HashMap<OsString, OsString>> = MaybeUninit::uninit();
 
 #[doc(hidden)]
@@ -163,23 +164,14 @@ pub fn decode_error_kind(errno: i32) -> ErrorKind {
 }
 
 unsafe fn init_kernel_arg(program_arg: usize) {
-    #[repr(C)]
-    struct Header {
-        args_ptr: usize,
-        envs_ptr: usize,
-    };
-
     #[allow(fuzzy_provenance_casts)]
-    let hdr = program_arg as *const Header;
-
-    ARGS = (*hdr).args_ptr;
-    let env_list = util::KStringList::new((*hdr).envs_ptr);
+    let arg = &*(program_arg as *const ProgramArgumentInner<'static>);
 
+    ARGS.write(arg.args);
     let mut envs = ENVS.write(HashMap::new());
 
-    for i in 0..env_list.len() {
-        let line = env_list.get(i);
-        let Some((key, value)) = line.split_once('=') else {
+    for pair in arg.env {
+        let Some((key, value)) = pair.split_once('=') else {
             continue;
         };
         let key = OsString::from_str(key).unwrap();
diff --git a/library/std/src/sys/yggdrasil/os.rs b/library/std/src/sys/yggdrasil/os.rs
index 6daa2f72d70..8cbdcf54335 100644
--- a/library/std/src/sys/yggdrasil/os.rs
+++ b/library/std/src/sys/yggdrasil/os.rs
@@ -6,7 +6,6 @@ use crate::io;
 use crate::marker::PhantomData;
 use crate::path::{Path, PathBuf};
 use crate::str::FromStr;
-use crate::sys::yggdrasil::util::KStringList;
 
 use yggdrasil_rt::Error as OsError;
 
diff --git a/library/std/src/sys/yggdrasil/util.rs b/library/std/src/sys/yggdrasil/util.rs
index d71d72440aa..27f914ff624 100644
--- a/library/std/src/sys/yggdrasil/util.rs
+++ b/library/std/src/sys/yggdrasil/util.rs
@@ -1,51 +1,6 @@
 use crate::env;
-use crate::mem::size_of;
 use crate::path::PathBuf;
 
-#[derive(Clone, Copy)]
-pub struct KStringList {
-    base: usize,
-    len: usize,
-}
-
-impl KStringList {
-    pub unsafe fn new(base: usize) -> Self {
-        if base == 0 {
-            panic!("Program arguments not initialized");
-        }
-
-        let len = unsafe {
-            #[allow(fuzzy_provenance_casts)]
-            (base as *const usize).read()
-        };
-
-        Self { base, len }
-    }
-
-    pub fn get(&self, index: usize) -> &'static str {
-        assert!(index < self.len);
-        let len = unsafe {
-            #[allow(fuzzy_provenance_casts)]
-            (Self::item(self.base, index) as *const usize).read()
-        };
-        let ptr = unsafe {
-            #[allow(fuzzy_provenance_casts)]
-            ((Self::item(self.base, index) + size_of::<usize>()) as *const *const u8).read()
-        };
-        let slice = unsafe { crate::slice::from_raw_parts(ptr, len) };
-
-        crate::str::from_utf8(slice).unwrap()
-    }
-
-    pub const fn len(&self) -> usize {
-        self.len
-    }
-
-    const fn item(base: usize, index: usize) -> usize {
-        base + (/* array len */1 + /* pair */ 2 * index) * size_of::<usize>()
-    }
-}
-
 pub fn resolve_binary(name: &str) -> Option<String> {
     // Already an absolute path
     if name.starts_with('/') {
diff --git a/yggdrasil-rt b/yggdrasil-rt
index df131ab13b5..a882ffa0281 160000
--- a/yggdrasil-rt
+++ b/yggdrasil-rt
@@ -1 +1 @@
-Subproject commit df131ab13b531b5ceee0ee53effb62e7e2967fbd
+Subproject commit a882ffa0281db2fdf162db7bf6a979a2bbbd54a0