Sio

A bootable programming language for BIOS/UEFI/Multiboot — work in progress.

Sio is a compiled language targeting boot sector and bootloader development. It compiles to NASM assembly, then to raw binary for QEMU or real hardware.

Current status: active development, not yet usable.

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What exists today

Component	状态
Parser (Parser.cs)	✅ @ppc= / @lib= / @inc= / @pctmode= parsing done
AST (AST.cs)	✅ Function/variable scanning, code generation framework
Head generation	✅ MBR, UEFI, Multiboot entry code generation
REPL/CLI	✅ Interactive mode with colored prompt
lib registration	✅ 12 libraries, 65 functions registered in Import()
Lib ASM stubs	✅ All variable slots and function labels written (all ; TODO)
ASM implementation	❌ All library functions are stubs — none actually work yet
pdc main() → MainBooter	✅ AST generates the label and code
pids / ids / udsp / cdsp	✅ AST recognizes them, generates jmp .exit patterns
if/while/ret	✅ AST generates conditional jumps
for / case	❌ Not implemented
Full compile pipeline	❌ No NASM invocation, no .bin output yet
Hello World	❌ Not yet — blocked on console.asm implementation

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Known issues

• Import() inserts library ASM, but all functions are ; TODO stubs
• Include() has duplicate IncludedCode append bug (appends per file per file)
• IncludedCode mixes comments into AST source (no separation between pure code and annotated code)
• MainParser() had infinite recursion (fixed now: Head() → Import() → AST.Paeser())
• String constant pool not generated (ParseValue("hello") produces label references but no db data)
• No NASA/AFL invocation — compiler outputs ASM text, stops there
• for loop not implemented in Generate()

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Quick start (when it works)

# Prerequisites
# - .NET 8.0 SDK
# - NASM
# - QEMU (optional, for testing)

# Build
git clone https://github.com/OFFMN-SHARP/sio.git
cd sio
dotnet build -c Release

# Write (when libraries are implemented)
@ppc=bios
@lib=console

pdc main():
    putsln("Hello from Sio!")
    ret(0)

# Eventually:
# ./sio build hello.sio → hello.bin
# qemu-system-x86_64 -hda hello.bin

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What's left to do

Priority order:

1. Implement console.asm — putsln / puts / clscr at minimum (INT 10h)
2. Implement tool.asm — mecpy / strlen / strcmp (used by other libs)
3. Add NASM invocation — shell out to NASM after ASM generation
4. Add string constant pool — collect "hello" literals, emit db data
5. Fix Include() duplicate bug — IncludedCode appended inside foreach loop
6. Implement diskio.asm — INT 13h read/write
7. Implement fat12.asm — depends on diskio
8. Implement remaining libs — serial, memgr, timekit, kbbus, powermgr, qasm, pe&elf, advpci&vga
9. Add for loop to AST Generate()
10. Add case (optional — can be expressed as if/elif/else)

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Architecture

.sio file
  ├── @ppc=bios/efi/mboot     → Head() generates entry code
  ├── @lib=xxx                → Import() registers 65+ functions
  ├── @inc=path               → Include() merges other .sio files
  └── pdc/pids functions      → AST.Paeser() generates ASM

Parser.cs → Head() → Import() → AST.Paeser()
                              ↓
                    Program.ParseredAsm (StringBuilder)
                              ↓
                    Invoke NASM → .bin file

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Library status

Library	Functions	ASM stubs	Impl. needed
console	13	✅ Labels + vars	❌ All ; TODO
diskio	3	✅	❌
fat12	10	✅	❌
serial	2	✅	❌
memgr	5	✅	❌
timekit	4	✅	❌
kbbus	3	✅	❌
powermgr	3	✅	❌
tool	6	✅	❌
qasm	4	✅	❌
pe&elf	7	✅	❌
advpci&vga	6	✅	❌

Total: 65 function slots, 0 implemented.

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NAME

SiO = silicon monoxide — an unstable intermediate oxide that exists briefly before becoming SiO₂. A bootloader is the same: a transient that exists just long enough to bring up the real system, then disappears. Sio the language is named after this idea.

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License

MIT