1 files changed, 105 insertions, 0 deletions
diff --git a/third_party/rust/redox_syscall/src/arch/x86.rs b/third_party/rust/redox_syscall/src/arch/x86.rs
new file mode 100644
index 0000000000..2f9301e0e0
--- /dev/null
+++ b/third_party/rust/redox_syscall/src/arch/x86.rs
@@ -0,0 +1,105 @@
+use core::{mem, slice};
+use core::arch::asm;
+use core::ops::{Deref, DerefMut};
+
+use super::error::{Error, Result};
+
+macro_rules! syscall {
+    ($($name:ident($a:ident, $($b:ident, $($c:ident, $($d:ident, $($e:ident, $($f:ident, )?)?)?)?)?);)+) => {
+        $(
+            pub unsafe fn $name(mut $a: usize, $($b: usize, $($c: usize, $($d: usize, $($e: usize, $($f: usize)?)?)?)?)?) -> Result<usize> {
+                asm!(
+                    "int 0x80",
+                    inout("eax") $a,
+                    $(
+                        in("ebx") $b,
+                        $(
+                            in("ecx") $c,
+                            $(
+                                in("edx") $d,
+                                $(
+                                    in("esi") $e,
+                                    $(
+                                        in("edi") $f,
+                                    )?
+                                )?
+                            )?
+                        )?
+                    )?
+                    options(nostack),
+                );
+
+                Error::demux($a)
+            }
+        )+
+    };
+}
+
+syscall! {
+    syscall0(a,);
+    syscall1(a, b,);
+    syscall2(a, b, c,);
+    syscall3(a, b, c, d,);
+    // Must be done custom because LLVM reserves ESI
+    //syscall4(a, b, c, d, e,);
+    //syscall5(a, b, c, d, e, f,);
+}
+
+pub unsafe fn syscall4(mut a: usize, b: usize, c: usize, d: usize, e: usize)
+                       -> Result<usize> {
+    asm!(
+        "xchg esi, {e}
+        int 0x80
+        xchg esi, {e}",
+        e = in(reg) e,
+        inout("eax") a,
+        in("ebx") b,
+        in("ecx") c,
+        in("edx") d,
+        options(nostack),
+    );
+
+    Error::demux(a)
+}
+
+pub unsafe fn syscall5(mut a: usize, b: usize, c: usize, d: usize, e: usize, f: usize)
+                       -> Result<usize> {
+    asm!(
+        "xchg esi, {e}
+        int 0x80
+        xchg esi, {e}",
+        e = in(reg) e,
+        inout("eax") a,
+        in("ebx") b,
+        in("ecx") c,
+        in("edx") d,
+        in("edi") f,
+        options(nostack),
+    );
+
+    Error::demux(a)
+}
+
+#[derive(Clone, Copy, Debug, Default)]
+#[repr(packed)]
+pub struct EnvRegisters {
+    pub fsbase: u32,
+    pub gsbase: u32,
+}
+
+impl Deref for EnvRegisters {
+    type Target = [u8];
+    fn deref(&self) -> &[u8] {
+        unsafe {
+            slice::from_raw_parts(self as *const EnvRegisters as *const u8, mem::size_of::<EnvRegisters>())
+        }
+    }
+}
+
+impl DerefMut for EnvRegisters {
+    fn deref_mut(&mut self) -> &mut [u8] {
+        unsafe {
+            slice::from_raw_parts_mut(self as *mut EnvRegisters as *mut u8, mem::size_of::<EnvRegisters>())
+        }
+    }
+}