vexos: move fs and stdio into respective modules

Author: tropicaaal

compiler/rustc_target/src/spec/targets/armv7a_vex_v5.rs

@@ -34,7 +34,7 @@ pub(crate) fn target() -> Target {
             description: Some("ARMv7-A Cortex-A9 VEX V5 Brain".into()),
             tier: Some(3),
             host_tools: Some(false),
-            std: Some(false),
+            std: Some(true),
         },
         pointer_width: 32,
         data_layout: "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64".into(),

library/Cargo.lock

@@ -394,6 +394,7 @@ dependencies = [
 [[package]]
 name = "vex-sdk"
 version = "0.27.0"
+source = "git+https://github.com/vexide/vex-sdk.git#67771319f730557693b2aa1e84c7ecd4831efb13"
 dependencies = [
  "rustc-std-workspace-core",
 ]

library/Cargo.toml

@@ -60,4 +60,4 @@ rustc-std-workspace-core = { path = 'rustc-std-workspace-core' }
 rustc-std-workspace-alloc = { path = 'rustc-std-workspace-alloc' }
 rustc-std-workspace-std = { path = 'rustc-std-workspace-std' }
 
-vex-sdk = { path = "../../vex-sdk/packages/vex-sdk" }
+vex-sdk = { git = "https://github.com/vexide/vex-sdk.git" }

library/std/Cargo.toml

@@ -90,7 +90,7 @@ r-efi = { version = "5.2.0", features = ['rustc-dep-of-std'] }
 r-efi-alloc = { version = "2.0.0", features = ['rustc-dep-of-std'] }
 
 [target.'cfg(target_os = "vexos")'.dependencies]
-vex-sdk = { version = "0.27.0", features = [
+vex-sdk = { git = "https://github.com/vexide/vex-sdk.git", features = [
     'rustc-dep-of-std',
 ], default-features = false }
 

library/std/src/sys/fs/mod.rs

@@ -35,6 +35,10 @@ cfg_select! {
         mod uefi;
         use uefi as imp;
     }
+    target_os = "vexos" => {
+        mod vexos;
+        use vexos as imp;
+    }
     target_os = "wasi" => {
         mod wasi;
         use wasi as imp;

library/std/src/sys/pal/vexos/fs.rs renamed to library/std/src/sys/fs/vexos.rs

@@ -505,11 +505,7 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
 }
 
 fn map_fresult(fresult: vex_sdk::FRESULT) -> io::Result<()> {
-    // VEX presumably uses a derivative of FatFs (most likely the xilffs library)
-    // for sdcard filesystem functions.
-    //
-    // Documentation for each FRESULT originates from here:
-    // <http://elm-chan.org/fsw/ff/doc/rc.html>
+    // VEX uses a derivative of FatFs (Xilinx's xilffs library) for filesystem operations.
     match fresult {
         vex_sdk::FRESULT::FR_OK => Ok(()),
         vex_sdk::FRESULT::FR_DISK_ERR => Err(io::Error::new(

library/std/src/sys/pal/vexos/mod.rs

@@ -1,18 +1,7 @@
-#[path = "../unsupported/args.rs"]
-pub mod args;
-pub mod env;
-pub mod fs;
-#[path = "../unsupported/io.rs"]
-pub mod io;
-#[path = "../unsupported/net.rs"]
-pub mod net;
 #[path = "../unsupported/os.rs"]
 pub mod os;
 #[path = "../unsupported/pipe.rs"]
 pub mod pipe;
-#[path = "../unsupported/process.rs"]
-pub mod process;
-pub mod stdio;
 pub mod thread;
 pub mod time;
 
@@ -41,39 +30,19 @@ pub unsafe extern "C" fn _start() -> ! {
         fn main() -> i32;
     }
 
-    // VEXos doesn't explicitly clean out .bss.
-    ptr::slice_from_raw_parts_mut(
-        addr_of_mut!(__bss_start),
-        addr_of_mut!(__bss_end).offset_from(addr_of_mut!(__bss_start)) as usize,
-    )
-    .as_mut()
-    .unwrap_unchecked()
-    .fill(0);
+    // Clear the .bss (uninitialized statics) section by filling it with zeroes.
+    // This is required, since the compiler assumes it will be zeroed on first access.
+    ptr::write_bytes(
+        &raw mut __bss_start,
+        0,
+        (&raw mut __bss_end).offset_from(&raw mut __bss_start) as usize,
+    );
 
     main();
 
     abort_internal()
 }
 
-// The code signature is a 32 byte header at the start of user programs that
-// identifies the owner and type of the program, as well as certain flags for
-// program behavior dictated by the OS. In the event that the user wants to
-// change this header, we use weak linkage so it can be overwritten.
-#[link_section = ".code_signature"]
-#[linkage = "weak"]
-#[used]
-static CODE_SIGNATURE: vex_sdk::vcodesig =
-    vex_sdk::vcodesig { magic: u32::from_le_bytes(*b"XVX5"), r#type: 0, owner: 2, options: 0 };
-
-// This function is needed by the panic runtime. The symbol is named in
-// pre-link args for the target specification, so keep that in sync.
-#[cfg(not(test))]
-#[no_mangle]
-// NB. used by both libunwind and libpanic_abort
-pub extern "C" fn __rust_abort() -> ! {
-    abort_internal()
-}
-
 // SAFETY: must be called only once during runtime initialization.
 // NOTE: this is not guaranteed to run, for example when Rust code is called externally.
 pub unsafe fn init(_argc: isize, _argv: *const *const u8, _sigpipe: u8) {}

library/std/src/sys/stdio/mod.rs

@@ -29,6 +29,10 @@ cfg_select! {
         mod uefi;
         pub use uefi::*;
     }
+    target_os = "vexos" => {
+        mod vexos;
+        pub use vexos::*;
+    }
     target_os = "wasi" => {
         mod wasi;
         pub use wasi::*;

library/std/src/sys/pal/vexos/stdio.rs renamed to library/std/src/sys/stdio/vexos.rs

@@ -1,14 +1,14 @@
 use crate::io;
 
-pub struct Stdin(());
-pub struct Stdout(());
-pub struct Stderr(());
+pub struct Stdin;
+pub struct Stdout;
+pub type Stderr = Stdout;
 
-pub const STDIO_CHANNEL: u32 = 1;
+const STDIO_CHANNEL: u32 = 1;
 
 impl Stdin {
     pub const fn new() -> Stdin {
-        Stdin(())
+        Stdin
     }
 }
 
@@ -34,7 +34,7 @@ impl io::Read for Stdin {
 
 impl Stdout {
     pub const fn new() -> Stdout {
-        Stdout(())
+        Stdout
     }
 }
 
@@ -64,38 +64,6 @@ impl io::Write for Stdout {
     }
 }
 
-impl Stderr {
-    pub const fn new() -> Stderr {
-        Stderr(())
-    }
-}
-
-impl io::Write for Stderr {
-    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        let written =
-            unsafe { vex_sdk::vexSerialWriteBuffer(STDIO_CHANNEL, buf.as_ptr(), buf.len() as u32) };
-
-        if written < 0 {
-            return Err(io::Error::new(
-                io::ErrorKind::Uncategorized,
-                "Internal write error occurred.",
-            ));
-        }
-
-        Ok(written as usize)
-    }
-
-    fn flush(&mut self) -> io::Result<()> {
-        unsafe {
-            while (vex_sdk::vexSerialWriteFree(STDIO_CHANNEL) as usize) != STDOUT_BUF_SIZE {
-                vex_sdk::vexTasksRun();
-            }
-        }
-
-        Ok(())
-    }
-}
-
 pub const STDIN_BUF_SIZE: usize = 4096;
 pub const STDOUT_BUF_SIZE: usize = 2048;