Merge branch 'main' into nes

fix

.gitmodules

@@ -1,6 +1,6 @@
 [submodule "picolibc"]
 	path = picolibc
 	url = https://github.com/picolibc/picolibc
-[submodule "user-apps/gboy/Peanut-GB"]
-	path = user-apps/gboy/Peanut-GB
+[submodule "user_apps/gboy/Peanut-GB"]
+	path = user_apps/gboy/Peanut-GB
 	url = https://github.com/deltabeard/Peanut-GB

Cargo.lock

@@ -110,6 +110,26 @@ version = "0.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9e1b586273c5702936fe7b7d6896644d8be71e6314cfe09d3167c95f712589e8"
 
+[[package]]
+name = "bindgen"
+version = "0.71.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5f58bf3d7db68cfbac37cfc485a8d711e87e064c3d0fe0435b92f7a407f9d6b3"
+dependencies = [
+ "bitflags 2.10.0",
+ "cexpr",
+ "clang-sys",
+ "itertools 0.10.5",
+ "log",
+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "syn 2.0.110",
+]
+
 [[package]]
 name = "bit-set"
 version = "0.5.3"
@@ -246,12 +266,42 @@ dependencies = [
  "toml",
 ]
 
+[[package]]
+name = "cc"
+version = "1.2.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "37521ac7aabe3d13122dc382493e20c9416f299d2ccd5b3a5340a2570cdeb0f3"
+dependencies = [
+ "find-msvc-tools",
+ "shlex",
+]
+
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
 
+[[package]]
+name = "clang-sys"
+version = "1.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b023947811758c97c59bf9d1c188fd619ad4718dcaa767947df1cadb14f39f4"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading",
+]
+
 [[package]]
 name = "clap"
 version = "3.2.25"
@@ -1077,6 +1127,12 @@ version = "2.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "37909eebbb50d72f9059c3b6d82c0463f2ff062c9e95845c43a6c9c0355411be"
 
+[[package]]
+name = "find-msvc-tools"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "52051878f80a721bb68ebfbc930e07b65ba72f2da88968ea5c06fd6ca3d3a127"
+
 [[package]]
 name = "fixed"
 version = "1.29.0"
@@ -1214,6 +1270,17 @@ dependencies = [
  "userlib",
 ]
 
+[[package]]
+name = "gboy"
+version = "0.1.0"
+dependencies = [
+ "bindgen",
+ "cc",
+ "embedded-graphics",
+ "selection_ui",
+ "userlib",
+]
+
 [[package]]
 name = "generic-array"
 version = "0.14.7"
@@ -1257,6 +1324,12 @@ dependencies = [
  "userlib",
 ]
 
+[[package]]
+name = "glob"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0cc23270f6e1808e30a928bdc84dea0b9b4136a8bc82338574f23baf47bbd280"
+
 [[package]]
 name = "goblin"
 version = "0.10.3"
@@ -1549,6 +1622,16 @@ version = "0.2.177"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2874a2af47a2325c2001a6e6fad9b16a53b802102b528163885171cf92b15976"
 
+[[package]]
+name = "libloading"
+version = "0.8.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7c4b02199fee7c5d21a5ae7d8cfa79a6ef5bb2fc834d6e9058e89c825efdc55"
+dependencies = [
+ "cfg-if",
+ "windows-link",
+]
+
 [[package]]
 name = "libredox"
 version = "0.1.10"
@@ -1604,6 +1687,12 @@ version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c3c8dda44ff03a2f238717214da50f65d5a53b45cd213a7370424ffdb6fae815"
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
 [[package]]
 name = "nb"
 version = "0.1.3"
@@ -1625,6 +1714,16 @@ version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "650eef8c711430f1a879fdd01d4745a7deea475becfb90269c06775983bbf086"
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.19"
@@ -1888,6 +1987,16 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "925383efa346730478fb4838dbe9137d2a47675ad789c546d150a6e1dd4ab31c"
 
+[[package]]
+name = "prettyplease"
+version = "0.2.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ff24dfcda44452b9816fff4cd4227e1bb73ff5a2f1bc1105aa92fb8565ce44d2"
+dependencies = [
+ "proc-macro2",
+ "syn 2.0.110",
+]
+
 [[package]]
 name = "proc-macro-error"
 version = "1.0.4"
@@ -2077,6 +2186,12 @@ dependencies = [
  "crc-any",
 ]
 
+[[package]]
+name = "rustc-hash"
+version = "2.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "357703d41365b4b27c590e3ed91eabb1b663f07c4c084095e60cbed4362dff0d"
+
 [[package]]
 name = "rustc_version"
 version = "0.2.3"
@@ -2216,6 +2331,12 @@ dependencies = [
  "keccak",
 ]
 
+[[package]]
+name = "shlex"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
+
 [[package]]
 name = "siphasher"
 version = "1.0.1"

Cargo.toml

@@ -10,6 +10,7 @@ members = [
   "user_apps/gallery",
   "user_apps/gif",
   "user_apps/wav_player",
+  "user_apps/gboy",
 ]
 
 [profile.release]

README.md

@@ -14,7 +14,7 @@ Current focus is on exanding applications and porting software, finding bugs in
 - **`userlib_sys/`** – C FFI bindings for kernel syscall
 - **`userlib/`** – Rust wrapper on top of `userlib_sys` 
 - **`picolib/`** – Built with ```just newlib```, and provides libc symbols when linking with C libraries 
-- **`user_apps/`** – Collection of userspace programs (gif player, wav player, calculator, snake, etc.)
+- **`user-apps/`** – Collection of userspace programs (gif player, wav player, calculator, snake, etc.)
 
 ## Features
 

justfile

@@ -42,6 +42,7 @@ userapps: cbindgen
     just userapp gallery
     just userapp gif
     just userapp wav_player
+    just userapp gboy
 
 copy-userapp app:
     cp ./target/{{target}}/release-binary/{{app}} /run/media/$(whoami)/PICOCALC/{{app}}.bin
@@ -54,6 +55,7 @@ copy-userapps:
     just copy-userapp gallery
     just copy-userapp gif
     just copy-userapp wav_player
+    just copy-userapp gboy
 
     DEV=$(lsblk -o LABEL,NAME -nr | awk -v L="PICOCALC" '$1==L {print "/dev/" $2}')
     udisksctl unmount -b "$DEV"

kernel/src/elf.rs

@@ -8,45 +8,38 @@ use core::ptr;
 use embedded_sdmmc::ShortFileName;
 use goblin::{
     elf::{
-        header::{EM_ARM, ET_DYN, EV_CURRENT, header32::Header},
+        header::header32::Header,
         program_header::program_header32::{PT_LOAD, ProgramHeader},
         reloc::R_ARM_RELATIVE,
         section_header::{SHT_REL, SHT_SYMTAB},
     },
-    elf32::{reloc::Rel, section_header::SectionHeader, sym::Sym},
+    elf32::{header, reloc::Rel, section_header::SectionHeader, sym::Sym},
 };
 use strum::IntoEnumIterator;
 use userlib_sys::{EntryFn, SyscallTable};
 
 const ELF32_HDR_SIZE: usize = 52;
 
-#[derive(Debug)]
-pub enum LoadError {
-    WrongMachine,
-    InvalidElf,
-    FailedToReadFile,
-    ElfIsNotPie,
-    UnknownRelocationType,
-    SyscallTableNotFound,
-}
-
-pub async unsafe fn load_binary(name: &ShortFileName) -> Result<(EntryFn, Bump), LoadError> {
+pub async unsafe fn load_binary(name: &ShortFileName) -> Option<(EntryFn, Bump)> {
     let mut sd_lock = SDCARD.get().lock().await;
-    let sd = sd_lock.as_mut().expect("Sdcard locked");
+    let sd = sd_lock.as_mut().unwrap();
 
     let mut header_buf = [0; ELF32_HDR_SIZE];
 
-    sd.read_file(name, |mut file| {
-        file.read(&mut header_buf)
-            .map_err(|_| LoadError::FailedToReadFile)?;
+    let (entry, bump) = sd
+        .read_file(name, |mut file| {
+            file.read(&mut header_buf).unwrap();
             let elf_header = Header::from_bytes(&header_buf);
 
-        validate_header(&elf_header)?;
+            // reject non-PIE
+            if elf_header.e_type != header::ET_DYN {
+                return None;
+            }
 
             let mut ph_buf = vec![0_u8; elf_header.e_phentsize as usize];
 
             let (total_size, min_vaddr, _max_vaddr) =
-            total_loadable_size(&mut file, elf_header, &mut ph_buf)?;
+                total_loadable_size(&mut file, elf_header, &mut ph_buf);
 
             let bump = Bump::with_capacity(total_size);
             let base = bump.alloc_slice_fill_default::<u8>(total_size);
@@ -54,54 +47,42 @@ pub async unsafe fn load_binary(name: &ShortFileName) -> Result<(EntryFn, Bump),
             // load each segment into bump, relative to base_ptr
             for i in 0..elf_header.e_phnum {
                 file.seek_from_start(elf_header.e_phoff + (elf_header.e_phentsize * i) as u32)
-                .map_err(|_| LoadError::FailedToReadFile)?;
-            file.read(&mut ph_buf)
-                .map_err(|_| LoadError::FailedToReadFile)?;
+                    .unwrap();
+                file.read(&mut ph_buf).unwrap();
                 let ph = cast_phdr(&ph_buf);
 
                 let seg_offset = (ph.p_vaddr - min_vaddr) as usize;
                 let segment = &mut base[seg_offset..seg_offset + ph.p_memsz as usize];
 
                 if ph.p_type == PT_LOAD {
-                load_segment(&mut file, &ph, segment)?;
+                    load_segment(&mut file, &ph, segment).unwrap();
                 }
             }
 
             for i in 0..elf_header.e_shnum {
-            let sh = read_section(&mut file, elf_header, i.into())?;
+                let sh = read_section(&mut file, elf_header, i.into());
 
                 if sh.sh_type == SHT_REL {
-                apply_relocations(&sh, min_vaddr, base.as_mut_ptr(), &mut file)?;
+                    apply_relocations(&sh, min_vaddr, base.as_mut_ptr(), &mut file).unwrap();
                 }
             }
 
-        patch_syscalls(elf_header, base.as_mut_ptr(), min_vaddr, &mut file)?;
+            patch_syscalls(elf_header, base.as_mut_ptr(), min_vaddr, &mut file).unwrap();
 
             // entry pointer is base_ptr + (entry - min_vaddr)
             let entry_ptr: EntryFn = unsafe {
                 core::mem::transmute(base.as_ptr().add((elf_header.e_entry - min_vaddr) as usize))
             };
 
-        Ok((entry_ptr, bump))
+            Some((entry_ptr, bump))
         })
         .await
-    .map_err(|_| LoadError::FailedToReadFile)?
+        .expect("Failed to read file")?;
+
+    Some((entry, bump))
 }
 
-fn validate_header(h: &Header) -> Result<(), LoadError> {
-    if h.e_type != ET_DYN {
-        return Err(LoadError::ElfIsNotPie);
-    }
-    if h.e_machine != EM_ARM {
-        return Err(LoadError::WrongMachine);
-    }
-    if h.e_version as u8 != EV_CURRENT {
-        return Err(LoadError::InvalidElf);
-    }
-    Ok(())
-}
-
-fn load_segment(file: &mut File, ph: &ProgramHeader, segment: &mut [u8]) -> Result<(), LoadError> {
+fn load_segment(file: &mut File, ph: &ProgramHeader, segment: &mut [u8]) -> Result<(), ()> {
     let filesz = ph.p_filesz as usize;
     let memsz = ph.p_memsz as usize;
 
@@ -113,10 +94,8 @@ fn load_segment(file: &mut File, ph: &ProgramHeader, segment: &mut [u8]) -> Resu
 
     while remaining > 0 {
         let to_read = core::cmp::min(remaining, buf.len());
-        file.seek_from_start(file_offset)
-            .map_err(|_| LoadError::FailedToReadFile)?;
-        file.read(&mut buf[..to_read])
-            .map_err(|_| LoadError::FailedToReadFile)?;
+        file.seek_from_start(file_offset).unwrap();
+        file.read(&mut buf[..to_read]).unwrap();
 
         segment[dst_offset..dst_offset + to_read].copy_from_slice(&buf[..to_read]);
 
@@ -138,16 +117,14 @@ fn apply_relocations(
     min_vaddr: u32,
     base: *mut u8,
     file: &mut File,
-) -> Result<(), LoadError> {
+) -> Result<(), ()> {
     let mut reloc = [0_u8; 8];
 
     let num_relocs = sh.sh_size as usize / sh.sh_entsize as usize;
 
     for i in 0..num_relocs {
-        file.seek_from_start(sh.sh_offset + (i as u32 * 8))
-            .map_err(|_| LoadError::FailedToReadFile)?;
-        file.read(&mut reloc)
-            .map_err(|_| LoadError::FailedToReadFile)?;
+        file.seek_from_start(sh.sh_offset + (i as u32 * 8)).unwrap();
+        file.read(&mut reloc).unwrap();
 
         let rel = cast_rel(&reloc);
 
@@ -163,7 +140,7 @@ fn apply_relocations(
                 }
             }
             _ => {
-                return Err(LoadError::UnknownRelocationType);
+                return Err(());
             }
         }
     }
@@ -175,17 +152,15 @@ fn patch_syscalls(
     base: *mut u8,
     min_vaddr: u32,
     file: &mut File,
-) -> Result<(), LoadError> {
+) -> Result<(), ()> {
     for i in 1..=elf_header.e_shnum {
-        let sh = read_section(file, elf_header, i.into())?;
+        let sh = read_section(file, elf_header, i.into());
 
         // find the symbol table
         if sh.sh_type == SHT_SYMTAB {
             let mut symtab_buf = vec![0u8; sh.sh_size as usize];
-            file.seek_from_start(sh.sh_offset)
-                .map_err(|_| LoadError::FailedToReadFile)?;
-            file.read(&mut symtab_buf)
-                .map_err(|_| LoadError::FailedToReadFile)?;
+            file.seek_from_start(sh.sh_offset).unwrap();
+            file.read(&mut symtab_buf).unwrap();
 
             // Cast buffer into symbols
             let sym_count = sh.sh_size as usize / sh.sh_entsize as usize;
@@ -194,23 +169,22 @@ fn patch_syscalls(
                     &symtab_buf[i * sh.sh_entsize as usize..(i + 1) * sh.sh_entsize as usize];
                 let sym = cast_sym(sym_bytes);
 
-                let str_sh = read_section(file, elf_header, sh.sh_link)?;
+                let str_sh = read_section(file, elf_header, sh.sh_link);
 
                 let mut name = Vec::new();
                 file.seek_from_start(str_sh.sh_offset + sym.st_name)
-                    .map_err(|_| LoadError::FailedToReadFile)?;
+                    .unwrap();
 
                 loop {
                     let mut byte = [0u8; 1];
-                    file.read(&mut byte)
-                        .map_err(|_| LoadError::FailedToReadFile)?;
+                    file.read(&mut byte).unwrap();
                     if byte[0] == 0 {
                         break;
                     }
                     name.push(byte[0]);
                 }
 
-                let symbol_name = core::str::from_utf8(&name).expect("symbol was not utf8");
+                let symbol_name = core::str::from_utf8(&name).unwrap();
                 if symbol_name == stringify!(SYS_CALL_TABLE) {
                     let table_base =
                         unsafe { base.add((sym.st_value as usize) - min_vaddr as usize) }
@@ -245,20 +219,20 @@ fn patch_syscalls(
             }
         }
     }
-    Err(LoadError::SyscallTableNotFound)
+    Err(())
 }
 
 fn total_loadable_size(
     file: &mut File,
     elf_header: &Header,
     ph_buf: &mut [u8],
-) -> Result<(usize, u32, u32), LoadError> {
+) -> (usize, u32, u32) {
     let mut min_vaddr = u32::MAX;
     let mut max_vaddr = 0u32;
     for i in 0..elf_header.e_phnum {
         file.seek_from_start(elf_header.e_phoff + (elf_header.e_phentsize * i) as u32)
-            .map_err(|_| LoadError::FailedToReadFile)?;
-        file.read(ph_buf).map_err(|_| LoadError::FailedToReadFile)?;
+            .unwrap();
+        file.read(ph_buf).unwrap();
         let ph = cast_phdr(ph_buf);
 
         if ph.p_type == PT_LOAD {
@@ -272,22 +246,17 @@ fn total_loadable_size(
     }
 
     let total_size = (max_vaddr - min_vaddr) as usize;
-    Ok((total_size, min_vaddr, max_vaddr))
+    (total_size, min_vaddr, max_vaddr)
 }
 
-fn read_section(
-    file: &mut File,
-    elf_header: &Header,
-    section: u32,
-) -> Result<SectionHeader, LoadError> {
+fn read_section(file: &mut File, elf_header: &Header, section: u32) -> SectionHeader {
     let mut sh_buf = vec![0_u8; elf_header.e_shentsize as usize];
 
     file.seek_from_start(elf_header.e_shoff + (elf_header.e_shentsize as u32 * section))
-        .map_err(|_| LoadError::FailedToReadFile)?;
-    file.read(&mut sh_buf)
-        .map_err(|_| LoadError::FailedToReadFile)?;
+        .unwrap();
+    file.read(&mut sh_buf).unwrap();
 
-    Ok(cast_shdr(&sh_buf))
+    cast_shdr(&sh_buf)
 }
 
 fn cast_phdr(buf: &[u8]) -> ProgramHeader {

kernel/src/main.rs

@@ -5,9 +5,6 @@
 #![allow(static_mut_refs)]
 #![feature(allocator_api)]
 #![feature(slice_ptr_get)]
-#![deny(warnings)]
-#![deny(clippy::redundant_clone)]
-#![deny(clippy::unwrap_used)]
 
 extern crate alloc;
 

kernel/src/storage.rs

@@ -52,13 +52,6 @@ impl Ord for FileName {
     }
 }
 
-#[derive(Debug)]
-pub enum SdCardError {
-    Volume0Missing,
-    RootDirMissing,
-    FileOpenFailed,
-}
-
 pub struct SdCard {
     det: Input<'static>,
     volume_mgr: VolMgr,
@@ -111,37 +104,30 @@ impl SdCard {
         res.map_err(|_| ())
     }
 
-    pub fn access_root_dir<R>(
-        &mut self,
-        mut access: impl FnMut(Dir) -> R,
-    ) -> Result<R, SdCardError> {
-        let volume0 = self
-            .volume_mgr
-            .open_volume(VolumeIdx(0))
-            .map_err(|_| SdCardError::Volume0Missing)?;
-        let root_dir = volume0
-            .open_root_dir()
-            .map_err(|_| SdCardError::RootDirMissing)?;
+    pub fn access_root_dir(&mut self, mut access: impl FnMut(Dir)) {
+        let volume0 = self.volume_mgr.open_volume(VolumeIdx(0)).unwrap();
+        let root_dir = volume0.open_root_dir().unwrap();
 
-        Ok(access(root_dir))
+        access(root_dir);
     }
 
-    pub async fn read_file<R>(
+    pub async fn read_file<T>(
         &mut self,
         name: &ShortFileName,
-        mut access: impl FnMut(File) -> R,
-    ) -> Result<R, SdCardError> {
+        mut access: impl FnMut(File) -> T,
+    ) -> Result<T, ()> {
+        let mut res = Err(());
         self.access_root_dir(|root_dir| {
-            let file = root_dir
-                .open_file_in_dir(name, Mode::ReadOnly)
-                .map_err(|_| SdCardError::FileOpenFailed)?;
+            if let Ok(file) = root_dir.open_file_in_dir(name, Mode::ReadOnly) {
+                res = Ok(access(file));
+            }
+        });
 
-            Ok(access(file))
-        })?
+        res
     }
 
     /// Returns a Vec of file names (long format) that match the given extension (e.g., "BIN")
-    pub fn list_files_by_extension(&mut self, ext: &str) -> Result<Vec<FileName>, SdCardError> {
+    pub fn list_files_by_extension(&mut self, ext: &str) -> Result<Vec<FileName>, ()> {
         let mut result = Vec::new();
 
         // Only proceed if card is inserted
@@ -165,7 +151,7 @@ impl SdCard {
                 }
             })
             .unwrap()
-        })?;
+        });
 
         Ok(result)
     }

kernel/src/syscalls.rs

@@ -190,7 +190,7 @@ pub extern "C" fn list_dir(
     let sd = guard.as_mut().unwrap();
 
     let mut wrote = 0;
-    let _ = sd.access_root_dir(|root| {
+    sd.access_root_dir(|root| {
         if dirs[0].is_empty() && dirs.len() >= 2 {
             unsafe {
                 if dir == "/" {
@@ -264,7 +264,7 @@ pub extern "C" fn read_file(
     let mut guard = SDCARD.get().try_lock().expect("Failed to get sdcard");
     let sd = guard.as_mut().unwrap();
     if !file.is_empty() {
-        let _ = sd.access_root_dir(|root| {
+        sd.access_root_dir(|root| {
             if let Ok(result) = recurse_file(&root, &components[1..count], |file| {
                 file.seek_from_start(start_from as u32).unwrap_or(());
                 file.read(buf).unwrap()
@@ -303,7 +303,7 @@ pub extern "C" fn write_file(
     let mut guard = SDCARD.get().try_lock().expect("Failed to get sdcard");
     let sd = guard.as_mut().unwrap();
     if !file.is_empty() {
-        let _ = sd.access_root_dir(|root| {
+        sd.access_root_dir(|root| {
             recurse_file(&root, &components[1..count], |file| {
                 file.seek_from_start(start_from as u32).unwrap();
                 file.write(buf).unwrap()
@@ -324,7 +324,7 @@ pub extern "C" fn file_len(str: *const u8, len: usize) -> usize {
     let mut guard = SDCARD.get().try_lock().expect("Failed to get sdcard");
     let sd = guard.as_mut().unwrap();
     if !file.is_empty() {
-        let _ = sd.access_root_dir(|root| {
+        sd.access_root_dir(|root| {
             if let Ok(result) = recurse_file(&root, &file[1..], |file| file.length()) {
                 len = result
             }

kernel/src/ui.rs

@@ -44,10 +44,9 @@ pub async fn ui_handler() {
                         selections.selections[selections.current_selection as usize].clone();
 
                     let entry = unsafe {
-                        match load_binary(&selection.short_name).await {
-                            Ok(entry) => entry,
-                            Err(e) => panic!("unable to load binary: {:?}", e),
-                        }
+                        load_binary(&selection.short_name)
+                            .await
+                            .expect("unable to load binary")
                     };
                     BINARY_CH.send(entry).await;
                 }

user_apps/gboy/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "gboy"
+version = "0.1.0"
+edition = "2024"
+
+[build-dependencies]
+bindgen = "0.71.0"
+cc = "1.2.44"
+
+[dependencies]
+userlib = { path = "../../userlib" }
+selection_ui = { path = "../../selection_ui" }
+embedded-graphics = "0.8.1"

user_apps/gboy/build.rs

@@ -0,0 +1,64 @@
+//! This build script copies the `memory.x` file from the crate root into
+//! a directory where the linker can always find it at build time.
+//! For many projects this is optional, as the linker always searches the
+//! project root directory -- wherever `Cargo.toml` is. However, if you
+//! are using a workspace or have a more complicated build setup, this
+//! build script becomes required. Additionally, by requesting that
+//! Cargo re-run the build script whenever `memory.x` is changed,
+//! updating `memory.x` ensures a rebuild of the application with the
+//! new memory settings.
+
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use std::path::PathBuf;
+
+fn main() {
+    bindgen();
+
+    // Put `memory.x` in our output directory and ensure it's
+    // on the linker search path.
+    let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
+    File::create(out.join("memory.x"))
+        .unwrap()
+        .write_all(include_bytes!("../memory.x"))
+        .unwrap();
+    println!("cargo:rustc-link-search={}", out.display());
+
+    println!("cargo:rerun-if-changed=memory.x");
+    println!("cargo:rustc-link-arg-bins=-Tmemory.x");
+}
+
+fn bindgen() {
+    let bindings = bindgen::Builder::default()
+        .header("Peanut-GB/peanut_gb.h")
+        .parse_callbacks(Box::new(bindgen::CargoCallbacks::new()))
+        .disable_nested_struct_naming()
+        .clang_arg("-I../../picolibc/newlib/libc/include/")
+        .clang_arg("-I../../picolibc/build/")
+        .use_core()
+        .generate()
+        .expect("Unable to generate bindings");
+
+    let out_path = PathBuf::from(env::var("OUT_DIR").unwrap());
+    bindings
+        .write_to_file(out_path.join("bindings.rs"))
+        .expect("Couldn't write bindings!");
+
+    cc::Build::new()
+        .define("PEANUT_GB_IS_LITTLE_ENDIAN", None)
+        .define("ENABLE_LCD", None)
+        .file("peanut_gb_stub.c")
+        .include("Peanut-GB")
+        // optimization flags
+        .flag("-Ofast")
+        .flag("-fdata-sections")
+        .flag("-ffunction-sections")
+        .flag("-mcpu=cortex-m33")
+        .flag("-mthumb")
+        .flag("-g0")
+        .compile("peanut_gb");
+
+    println!("cargo:rustc-link-search=Peanut-GB");
+    println!("cargo:rustc-link-lib=peanut_gb");
+}

user_apps/gboy/peanut_gb_stub.c

@@ -0,0 +1 @@
+#include <peanut_gb.h>

user_apps/gboy/src/main.rs

@@ -0,0 +1,206 @@
+#![no_std]
+#![no_main]
+#![allow(static_mut_refs)]
+
+extern crate alloc;
+use alloc::{vec, vec::Vec};
+use core::{cell::LazyCell, mem::MaybeUninit, panic::PanicInfo};
+use embedded_graphics::{
+    mono_font::{MonoTextStyle, ascii::FONT_6X10},
+    pixelcolor::Rgb565,
+    prelude::RgbColor,
+};
+use selection_ui::{SelectionUi, SelectionUiError, draw_text_center};
+use userlib::{
+    display::Display,
+    format,
+    fs::{Entries, file_len, list_dir, read_file, write_file},
+    get_key,
+    keyboard::{KeyCode, KeyState},
+    println,
+};
+
+mod peanut;
+use peanut::gb_run_frame;
+
+use crate::peanut::{
+    JOYPAD_A, JOYPAD_B, JOYPAD_DOWN, JOYPAD_LEFT, JOYPAD_RIGHT, JOYPAD_SELECT, JOYPAD_START,
+    JOYPAD_UP, gb_cart_ram_read, gb_cart_ram_write, gb_error, gb_get_rom_name, gb_get_save_size,
+    gb_init, gb_init_lcd, gb_reset, gb_rom_read, gb_s, lcd_draw_line,
+};
+
+static mut DISPLAY: LazyCell<Display> = LazyCell::new(|| Display::take().unwrap());
+
+const RAM_SIZE: usize = 32 * 1024; // largest ram size is 32k
+static mut RAM: [u8; RAM_SIZE] = [0; RAM_SIZE];
+
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    println!("user panic: {} @ {:?}", info.message(), info.location(),);
+    loop {}
+}
+
+#[unsafe(no_mangle)]
+pub extern "Rust" fn _start() {
+    main()
+}
+
+const GAME_PATH: &'static str = "/games/gameboy";
+
+static mut GAME_ROM: Option<Vec<u8>> = None;
+
+pub fn main() {
+    println!("Starting Gameboy app");
+
+    let mut entries = Entries::new();
+    list_dir(GAME_PATH, &mut entries);
+
+    let mut files = entries.entries();
+    files.retain(|e| {
+        let ext = e.extension().unwrap_or("");
+        ext == "gb" || ext == "GB"
+    });
+    let mut roms = files.iter().map(|e| e.full_name()).collect::<Vec<&str>>();
+    roms.sort();
+
+    let selection = {
+        let display = unsafe { &mut *DISPLAY };
+        let mut selection_ui = SelectionUi::new(&roms);
+        match selection_ui.run_selection_ui(display) {
+            Ok(maybe_sel) => maybe_sel,
+            Err(e) => match e {
+                SelectionUiError::SelectionListEmpty => {
+                    draw_text_center(
+                        display,
+                        &format!("No Roms were found in {}", GAME_PATH),
+                        MonoTextStyle::new(&FONT_6X10, Rgb565::RED),
+                    )
+                    .expect("Display Error");
+                    None
+                }
+                SelectionUiError::DisplayError(_) => panic!("Display Error"),
+            },
+        }
+    };
+
+    assert!(selection.is_some());
+
+    let file_name = format!("{}/{}", GAME_PATH, roms[selection.unwrap()]);
+    let size = file_len(&file_name);
+    unsafe { GAME_ROM = Some(vec![0_u8; size]) };
+    let read = read_file(&file_name, 0, unsafe { GAME_ROM.as_mut().unwrap() });
+    assert!(size == read);
+    println!("Rom size: {}", read);
+
+    let mut gb = MaybeUninit::<gb_s>::uninit();
+
+    let init_status = unsafe {
+        gb_init(
+            gb.as_mut_ptr(),
+            Some(gb_rom_read),
+            Some(gb_cart_ram_read),
+            Some(gb_cart_ram_write),
+            Some(gb_error),
+            core::ptr::null_mut(),
+        )
+    };
+    println!("gb init status: {}", init_status);
+
+    unsafe {
+        load_save(&mut gb.assume_init());
+    }
+
+    unsafe {
+        gb_init_lcd(gb.as_mut_ptr(), Some(lcd_draw_line));
+
+        // enable frame skip
+        // gb.assume_init().direct.set_frame_skip(!true); // active low
+    };
+
+    loop {
+        let event = get_key();
+        let button = match event.key {
+            KeyCode::Esc => {
+                unsafe { write_save(&mut gb.assume_init()) };
+                break;
+            }
+            KeyCode::Char('r') => {
+                unsafe { gb_reset(gb.as_mut_ptr()) };
+                continue;
+            }
+            KeyCode::Tab => JOYPAD_START as u8,
+            KeyCode::Del => JOYPAD_SELECT as u8,
+            KeyCode::Enter => JOYPAD_A as u8,
+            KeyCode::Backspace => JOYPAD_B as u8,
+            KeyCode::Up => JOYPAD_UP as u8,
+            KeyCode::Down => JOYPAD_DOWN as u8,
+            KeyCode::Left => JOYPAD_LEFT as u8,
+            KeyCode::Right => JOYPAD_RIGHT as u8,
+            _ => 0,
+        };
+
+        if button != 0 {
+            unsafe {
+                // bindgen incorrectly generates direct so manual manipulation is required :(
+                let direct_ptr = &mut gb.assume_init().direct as *mut _ as *mut u8;
+                let joypad_ptr = direct_ptr.add(2); // this is the joypad bitfield byte
+
+                if let KeyState::Pressed = event.state {
+                    *joypad_ptr &= !button;
+                } else if let KeyState::Released = event.state {
+                    *joypad_ptr |= button;
+                }
+
+                println!("joypad: {:b}", *joypad_ptr);
+            }
+        }
+
+        unsafe {
+            gb_run_frame(gb.as_mut_ptr());
+        }
+    }
+}
+
+unsafe fn load_save(gb: &mut gb_s) {
+    let mut buf = [0; 16];
+
+    unsafe {
+        gb_get_rom_name(gb, buf.as_mut_ptr());
+
+        let save_size = gb_get_save_size(gb);
+
+        if save_size > 0 {
+            read_file(
+                &format!(
+                    "{}/saves/{}.sav",
+                    GAME_PATH,
+                    str::from_utf8(&buf).expect("bad rom name")
+                ),
+                0,
+                &mut RAM,
+            );
+        }
+    }
+}
+
+unsafe fn write_save(gb: &mut gb_s) {
+    let mut buf = [0; 16];
+
+    unsafe {
+        gb_get_rom_name(gb, buf.as_mut_ptr());
+
+        let save_size = gb_get_save_size(gb);
+
+        if save_size > 0 {
+            write_file(
+                &format!(
+                    "{}/saves/{}.sav",
+                    GAME_PATH,
+                    str::from_utf8(&buf).expect("bad rom name")
+                ),
+                0,
+                &mut RAM,
+            );
+        }
+    }
+}

user_apps/gboy/src/peanut.rs

@@ -0,0 +1,102 @@
+#![allow(non_upper_case_globals)]
+#![allow(non_camel_case_types)]
+#![allow(non_snake_case)]
+
+use crate::{DISPLAY, GAME_ROM, RAM};
+
+#[allow(unused)]
+include!(concat!(env!("OUT_DIR"), "/bindings.rs"));
+
+use embedded_graphics::{pixelcolor::Rgb565, prelude::Point, Drawable};
+use userlib::{display::Pixel565, println};
+
+pub const GBOY_WIDTH: usize = 160;
+pub const GBOY_HEIGHT: usize = 144;
+
+pub unsafe extern "C" fn gb_rom_read(_gb: *mut gb_s, addr: u32) -> u8 {
+    unsafe { GAME_ROM.as_ref().unwrap()[addr as usize] }
+}
+
+pub unsafe extern "C" fn gb_cart_ram_read(_gb: *mut gb_s, addr: u32) -> u8 {
+    unsafe { RAM[addr as usize] }
+}
+
+pub unsafe extern "C" fn gb_cart_ram_write(_gb: *mut gb_s, addr: u32, val: u8) {
+    unsafe { RAM[addr as usize] = val }
+}
+
+pub unsafe extern "C" fn gb_error(_gb: *mut gb_s, err: gb_error_e, addr: u16) {
+    let e = match err {
+        0 => "UNKNOWN ERROR",
+        1 => "INVALID OPCODE",
+        2 => "INVALID READ",
+        3 => "INVALID WRITE",
+        4 => "HALT FOREVER",
+        5 => "INVALID MAX",
+        _ => unreachable!(),
+    };
+
+    println!("PeanutGB error: {}, addr: {}", e, addr);
+}
+
+const NUM_PALETTES: usize = 3;
+const SHADES_PER_PALETTE: usize = 4;
+
+const PALETTES: [[Rgb565; SHADES_PER_PALETTE]; NUM_PALETTES] = [
+    [
+        Rgb565::new(8, 24, 32),
+        Rgb565::new(52, 104, 86),
+        Rgb565::new(136, 192, 112),
+        Rgb565::new(224, 248, 208),
+    ], // BG
+    [
+        Rgb565::new(8, 24, 32),
+        Rgb565::new(52, 104, 86),
+        Rgb565::new(136, 192, 112),
+        Rgb565::new(224, 248, 208),
+    ], // OBJ0
+    [
+        Rgb565::new(8, 24, 32),
+        Rgb565::new(52, 104, 86),
+        Rgb565::new(136, 192, 112),
+        Rgb565::new(224, 248, 208),
+    ], // OBJ1
+];
+
+pub unsafe extern "C" fn lcd_draw_line(_gb: *mut gb_s, pixels: *const u8, line: u8) {
+    if line < GBOY_HEIGHT as u8 {
+        let pixels = unsafe { core::slice::from_raw_parts(pixels, GBOY_WIDTH) };
+        let y = line as u16;
+
+        for (x, &p) in pixels.iter().enumerate() {
+            let palette_idx = ((p & 0xF0) >> 4) as usize;
+            let shade_idx = (p & 0x03) as usize;
+
+            let color = PALETTES
+                .get(palette_idx)
+                .and_then(|pal| pal.get(shade_idx))
+                .copied()
+                .unwrap_or(Rgb565::new(0, 0, 0));
+
+            // let sx = (x as u16) * 2;
+            // let sy = y * 2;
+
+            // draw_color(color, sx, sy);
+            // draw_color(color, sx + 1, sy);
+            // draw_color(color, sx, sy + 1);
+            // draw_color(color, sx + 1, sy + 1);
+            //
+            draw_color(color, x as u16, y as u16);
+        }
+    }
+}
+
+fn draw_color(color: Rgb565, x: u16, y: u16) {
+    let mut pixel = Pixel565::default();
+    pixel.0 = Point::new(x.into(), y.into());
+    pixel.1 = color;
+
+    unsafe {
+        pixel.draw(&mut *DISPLAY).unwrap();
+    }
+}