Add the rust std as a custom sysroot

library/std/src/sys/alloc/survos.rs

@@ -0,0 +1,104 @@
+#![allow(fuzzy_provenance_casts)]
+
+use crate::alloc::{GlobalAlloc, Layout, System};
+
+#[stable(feature = "alloc_system_type", since = "1.28.0")]
+unsafe impl GlobalAlloc for System {
+    unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
+        alloc(layout)
+    }
+
+    unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
+        dealloc(ptr, layout)
+    }
+}
+
+#[repr(u64)]
+enum SysCall {
+    Read = 0,
+    Write = 1,
+    Open = 2,
+    Close = 3,
+    Seek = 8,
+    Alloc = 40,
+    Dealloc = 41,
+    Spawn = 58,
+    ExecVE = 59,
+    Exit = 60,
+    NanoSleep = 101,
+    WriteIntTemp = 998,
+    WriteTemp = 999,
+    Unimplemented = 1 << 31,
+}
+
+#[allow(clippy::too_many_arguments)]
+unsafe fn _syscall(
+    syscall: SysCall,
+    mut a1: u64,
+    mut a2: u64,
+    mut a3: u64,
+    mut a4: u64,
+    mut a5: u64,
+    mut a6: u64,
+    mut a7: u64,
+) -> (u64, u64, u64, u64, u64, u64, u64, u64) {
+    let mut a0 = syscall as u64;
+    unsafe {
+        core::arch::asm!(
+            "ecall",
+            inlateout("a0") a0,
+            inlateout("a1") a1,
+            inlateout("a2") a2,
+            inlateout("a3") a3,
+            inlateout("a4") a4,
+            inlateout("a5") a5,
+            inlateout("a6") a6,
+            inlateout("a7") a7,
+            clobber_abi("system")
+        );
+    }
+    (a0, a1, a2, a3, a4, a5, a6, a7)
+}
+
+macro_rules! syscall {
+    ($syscall:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr, $a7:expr) => {
+        _syscall($syscall, $a1, $a2, $a3, $a4, $a5, $a6, $a7)
+    };
+    ($syscall:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr, $a6:expr) => {
+        syscall!($syscall, $a1, $a2, $a3, $a4, $a5, $a6, 0)
+    };
+    ($syscall:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr, $a5:expr) => {
+        syscall!($syscall, $a1, $a2, $a3, $a4, $a5, 0)
+    };
+    ($syscall:expr, $a1:expr, $a2:expr, $a3:expr, $a4:expr) => {
+        syscall!($syscall, $a1, $a2, $a3, $a4, 0)
+    };
+    ($syscall:expr, $a1:expr, $a2:expr, $a3:expr) => {
+        syscall!($syscall, $a1, $a2, $a3, 0)
+    };
+    ($syscall:expr, $a1:expr, $a2:expr) => {
+        syscall!($syscall, $a1, $a2, 0)
+    };
+    ($syscall:expr, $a1:expr) => {
+        syscall!($syscall, $a1, 0)
+    };
+    ($syscall:expr) => {
+        syscall!($syscall, 0)
+    };
+}
+
+fn alloc(layout: Layout) -> *mut u8 {
+    unsafe {
+        let size = layout.size();
+        let align = layout.align();
+        let (ptr, ..) = syscall!(SysCall::Alloc, size as u64, align as u64);
+        ptr as *mut u8
+    }
+}
+fn dealloc(ptr: *mut u8, layout: core::alloc::Layout) {
+    unsafe {
+        let size = layout.size();
+        let align = layout.align();
+        syscall!(SysCall::Dealloc, ptr as u64, size as u64, align as u64);
+    }
+}

library/std/src/sys/pal/survos.rs

@@ -0,0 +1,11 @@
+/// # Safety
+/// `argc` and `argv` are passed by the kernel
+#[unsafe(no_mangle)]
+#[stable(feature = "rust1", since = "1.0.0")]
+pub unsafe extern "C" fn _start(argc: isize, argv: *const *const u8) -> isize {
+    unsafe extern "C" {
+        fn main(argc: isize, argv: *const *const u8) -> isize;
+    }
+
+    unsafe { main(argc, argv) }
+}