post-02

.cargo/config

@@ -0,0 +1,5 @@
+[build]
+target = "x86_64-blog_os.json"
+
+[target.'cfg(target_os = "none")']
+runner = "bootimage runner"

Cargo.lock

@@ -3,4 +3,14 @@
 [[package]]
 name = "blog_os"
 version = "0.1.0"
+dependencies = [
+ "bootloader 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
+[[package]]
+name = "bootloader"
+version = "0.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[metadata]
+"checksum bootloader 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "45dd858bd74a742ec0fe887722952c263abd0825aa8d33a3704917a97d7bd41e"

Cargo.toml

@@ -1,12 +1,13 @@
 [package]
 name = "blog_os"
 version = "0.1.0"
-authors = ["Timothy Warren <twarren@nabancard.com>"]
+authors = ["Timothy Warren <tim@timshomepage.net>"]
 edition = "2018"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+bootloader = "0.8.1"
 
 [profile.dev]
 panic = "abort"

src/main.rs

@@ -9,7 +9,18 @@ fn panic(_info: &PanicInfo) -> ! {
     loop {}
 }
 
+static HELLO: &[u8] = b"Hello World!";
+
 #[no_mangle]
 pub extern "C" fn _start() -> ! {
+    let vga_buffer = 0xb8000 as *mut u8;
+
+    for (i, &byte) in HELLO.iter().enumerate() {
+        unsafe {
+            *vga_buffer.offset(i as isize * 2) = byte;
+            *vga_buffer.offset(i as isize * 2 + 1) = 0xb;
+        }
+    }
+
     loop {}
 }

x86_64-blog_os.json

@@ -0,0 +1,15 @@
+{
+  "llvm-target": "x86_64-unknown-none",
+  "data-layout": "e-m:e-i64:64-f80:128-n8:16:32:64-S128",
+  "arch": "x86_64",
+  "target-endian": "little",
+  "target-pointer-width": "64",
+  "target-c-int-width": "32",
+  "os": "none",
+  "executables": true,
+  "linker-flavor": "ld.lld",
+  "linker": "rust-lld",
+  "panic-strategy": "abort",
+  "disable-redzone": true,
+  "features": "-mmx,-sse,+soft-float"
+}