Avoid gcc dependency

Cargo.toml

@@ -14,4 +14,4 @@ lto = "thin"
 cstr_core = { version = "0.2.4", default-features = false, features = ["nightly"] }
 
 [build-dependencies]
-cc = "1.0.72"
+nasm-rs = "0.2.2"

Makefile.toml

@@ -0,0 +1,26 @@
+[env.production]
+RELEASE_FLAG = "--release"
+
+[tasks.default]
+alias = "all"
+
+[tasks.all]
+dependencies = ["objcopy"]
+
+[tasks.clean]
+command = "cargo"
+args = ["clean"]
+
+[tasks.build-1]
+command = "cargo"
+args = ["build", "@@remove-empty(RELEASE_FLAG)"]
+
+[tasks.build]
+command = "cargo"
+args = ["build"]
+
+[tasks.objcopy]
+command = "cargo"
+args = ["objcopy", "@@remove-empty(RELEASE_FLAG)", "--", "-Obinary"]
+dependencies = ["build-1"]
+install_crate = { crate_name = "cargo-binutils", binary = "rust-objcopy", test_arg = ["--help"] }

README.md

@@ -0,0 +1,7 @@
+# Hello-world example for KolibriOS
+
+Project uses [cargo-make](https://github.com/sagiegurari/cargo-make) for building steps.
+Also you need a working [NASM](https://nasm.us/).
+
+Once installed building is trivial then: `cargo make --profile production` produces
+a ready-to-use binary at `target/i686-kolibri/release/hw_kolibri`.

build.rs

@@ -1,8 +1,5 @@
 fn main() {
-    println!("cargo:rerun-if-changed=src/syscalls.c");
-    cc::Build::new()
-        .file("src/syscalls.c")
-        .flag("-fno-PIC") // for some reason `pic(false)` doesn't work
-        .static_flag(true)
-        .compile("syscalls");
+    println!("cargo:rerun-if-changed=src/syscalls.S");
+    nasm_rs::compile_library_args("libsyscalls.a", &["src/syscalls.S"], &["-f elf32"])
+        .expect("failed to compile assembly");
 }

i686-kolibri.json

@@ -7,18 +7,9 @@
     "has-elf-tls": false,
     "has-rpath": true,
     "is-builtin": false,
-    "linker-flavor": "gcc",
-    "linker": "gcc",
+    "linker-flavor": "ld.lld",
+    "linker": "rust-lld",
     "llvm-target": "i686-unknown-none-code32",
-    "pre-link-args": {
-        "gcc": [
-            "-nostdlib",
-            "-Wl,--build-id=none",
-            "-Wl,--as-needed",
-            "-Wl,-z,noexecstack",
-            "-m32"
-        ]
-    },
     "max-atomic-width": 32,
     "os": "none",
     "relocation-model": "static",

link.x

@@ -2,8 +2,6 @@ PATH_SIZE   = 1024;
 PARAMS_SIZE =  256;
 STACK_SIZE  = 1024;
 
-OUTPUT_FORMAT("binary")
-
 SECTIONS
 {
 . = 0x24;

src/sys.rs

@@ -1,16 +1,22 @@
 #[link(name = "syscalls")]
 extern "C" {
+    #[link_name = "_start_window_draw"]
     pub fn start_window_draw();
 
+    #[link_name = "_end_window_draw"]
     pub fn end_window_draw();
 
-    #[link_name = "exit0"]
+    #[link_name = "_exit"]
     pub fn exit() -> !;
 
+    #[link_name = "_define_window"]
     pub fn define_window(ebx: u32, ecx: u32, edx: u32, edi: u32);
+    #[link_name = "_display_message"]
     pub fn display_message(ebx: u32, ecx: u32, edx: u32, edi: u32, esi: u32);
 
+    #[link_name = "_wait_event"]
     pub fn wait_event() -> u32;
 
+    #[link_name = "_pressed_key"]
     pub fn pressed_key() -> u32;
 }

src/syscalls.S

@@ -0,0 +1,67 @@
+BITS 32
+
+section .text
+    global _exit
+    global _start_window_draw
+    global _end_window_draw
+    global _define_window
+    global _display_message
+    global _wait_event
+    global _pressed_key
+
+_exit:
+    mov eax, -1
+    int 0x40
+
+_start_window_draw:
+    mov eax, 0xc
+    mov ebx, 1
+    int 0x40
+    ret
+
+_end_window_draw:
+    mov eax, 0xc
+    mov ebx, 2
+    int 0x40
+    ret
+
+_define_window:
+    push edi
+    push ebx
+    xor eax, eax
+    mov ebx, dword [esp + 0x14]
+    mov ecx, dword [esp + 0x18]
+    mov edx, dword [esp + 0x1c]
+    mov edi, dword [esp + 0x20]
+    mov ebx, 2
+    int 0x40
+    pop ebx
+    pop edi
+    ret
+
+_display_message:
+    push edi
+    push esi
+    push ebx
+    mov eax, 4
+    mov ebx, dword [esp + 0x14]
+    mov ecx, dword [esp + 0x18]
+    mov edx, dword [esp + 0x1c]
+    mov esi, dword [esp + 0x20]
+    mov edi, dword [esp + 0x24]
+    mov ebx, 2
+    int 0x40
+    pop ebx
+    pop esi
+    pop edi
+    ret
+
+_wait_event:
+    mov eax, 0xa
+    int 0x40
+    ret
+
+_pressed_key:
+    mov eax, 2
+    int 0x40
+    ret

src/syscalls.c

@@ -1,54 +0,0 @@
-void start_window_draw() {
-    __asm__ volatile (
-        "int $0x40;"
-        :: "a"(12), "b"(1)
-    );
-}
-
-void end_window_draw() {
-    __asm__ volatile (
-        "int $0x40;"
-        :: "a"(12), "b"(2)
-    );
-}
-
-void exit0() {
-    __asm__ volatile (
-        "int $0x40;"
-        :: "a"(-1)
-    );
-}
-
-void define_window(unsigned ebx, unsigned ecx, unsigned edx, unsigned edi) {
-    __asm__ volatile (
-        "int $0x40;"
-        :: "a"(0), "b"(ebx), "c"(ecx), "d"(edx), "D"(edi)
-        : "memory"
-    );
-}
-
-void display_message(unsigned ebx, unsigned ecx, unsigned edx, unsigned edi, unsigned esi) {
-    __asm__ volatile (
-        "int $0x40;"
-        :: "a"(4), "b"(ebx), "c"(ecx), "d"(edx), "D"(edi), "S"(esi)
-        : "memory"
-    );
-}
-
-unsigned wait_event() {
-    unsigned res;
-    __asm__ volatile (
-        "int $0x40;"
-        : "=r"(res) : "a"(10)
-    );
-    return res;
-}
-
-unsigned pressed_key() {
-    unsigned res;
-    __asm__ volatile (
-        "int $0x40;"
-        : "=r"(res) : "a"(2)
-    );
-    return res;
-}