Merge #51

51: Rewrite build system r=phil-opp a=phil-opp

- [x] Blocked on rust-lang/rust#59351
- [x] Blocked on rust-lang/cargo#6778

Fixes #33 
Fixes #48

Co-authored-by: Philipp Oppermann <dev@phil-opp.com>

.cargo/config

@@ -0,0 +1,2 @@
+[build]
+target = "x86_64-bootloader.json"

Cargo.toml

@@ -9,6 +9,7 @@ description = "An experimental pure-Rust x86 bootloader."
 repository = "https://github.com/rust-osdev/bootloader"
 publish-lockfile = true
 edition = "2018"
+build = "build.rs"
 
 [dependencies]
 xmas-elf = "0.6.2"
@@ -21,6 +22,9 @@ version = "0.2.4"
 default-features = false
 features = ["unicode"]
 
+[build-dependencies]
+llvm-tools = "0.1"
+
 [features]
 default = []
 vga_320x200 = []

azure-pipelines.yml

@@ -10,8 +10,6 @@ trigger:
     - trying
     # Build pull requests.
     - master
-    # Build post braches
-    - post-*
 
 strategy:
   matrix:
@@ -64,11 +62,11 @@ steps:
   displayName: 'Print Rust Version'
   continueOnError: true
 
-- script: rustup component add rust-src
-  displayName: 'Install Rustup Src Component'
+- script: rustup component add rust-src llvm-tools-preview
+  displayName: 'Install Rustup Components'
 
-- script: cargo install cargo-xbuild bootimage --debug
-  displayName: 'Install cargo-xbuild and bootimage'
+- script: cargo install cargo-xbuild cargo-binutils --debug
+  displayName: 'Install cargo-xbuild cargo-binutils'
 
 - script: sudo apt update && sudo apt install qemu-system-x86
   condition: eq( variables['Agent.OS'], 'Linux' )
@@ -96,20 +94,15 @@ steps:
   workingDirectory: example-kernel
   displayName: 'Build Example Kernel'
 
-- script: cargo run -- --kernel ../example-kernel/target/x86_64-example-kernel/debug/example-kernel
-  workingDirectory: builder
+- script: cargo xbuild --release
   displayName: 'Build Bootloader'
+  env: { KERNEL: "example-kernel/target/x86_64-example-kernel/debug/example-kernel" }
+
+- script: cargo objcopy -- -I elf64-x86-64 -O binary --binary-architecture=i386:x86-64 target/x86_64-bootloader/release/bootloader target/x86_64-bootloader/release/bootloader.bin
+  displayName: 'Convert Bootloader ELF to Binary'
 
 - bash: |
-    qemu-system-x86_64 -drive format=raw,file=target/x86_64-bootloader/release/bootimage.bin -device isa-debug-exit,iobase=0xf4,iosize=0x04 -display none
+    qemu-system-x86_64 -drive format=raw,file=target/x86_64-bootloader/release/bootloader.bin -device isa-debug-exit,iobase=0xf4,iosize=0x04 -display none
     if [ $? -eq 123 ]; then (exit 0); else (exit 1); fi
   displayName: 'Test Bootloader'
 
-- script: cargo run -- --kernel ../example-kernel/target/x86_64-example-kernel/debug/example-kernel --features vga_320x200
-  workingDirectory: builder
-  displayName: 'Build Bootloader (Feature vga_320x200)'
-
-- bash: |
-    qemu-system-x86_64 -drive format=raw,file=target/x86_64-bootloader/release/bootimage.bin -device isa-debug-exit,iobase=0xf4,iosize=0x04 -display none
-    if [ $? -eq 123 ]; then (exit 0); else (exit 1); fi
-  displayName: 'Test Bootloader (Feature vga_320x200)'

build.rs

@@ -0,0 +1,82 @@
+use std::{env, path::{Path, PathBuf}, process::{self, Command}};
+
+fn main() {
+    let target = env::var("TARGET").expect("TARGET not set");
+    if Path::new(&target)
+        .file_stem()
+        .expect("target has no file stem")
+        != "x86_64-bootloader"
+    {
+        return;
+    }
+
+    let out_dir = PathBuf::from(env::var("OUT_DIR").expect("OUT_DIR not set"));
+    let kernel = PathBuf::from(match env::var("KERNEL") {
+        Ok(kernel) => kernel,
+        Err(_) => {
+            eprintln!(
+                "The KERNEL environment variable must be set for building the bootloader."
+            );
+            process::exit(1);
+        }
+    });
+
+    let kernel_file_name = kernel.file_name().expect("KERNEL has no valid file name").to_str().expect("kernel file name not valid utf8");
+    let kernel_file_name_replaced = kernel_file_name.replace('-', "_");
+    let kernel_out_path = out_dir.join(format!("kernel_bin-{}.o", kernel_file_name));
+    let kernel_archive_path = out_dir.join(format!("libkernel_bin-{}.a", kernel_file_name));
+
+    let llvm_tools = match llvm_tools::LlvmTools::new() {
+        Ok(tools) => tools,
+        Err(llvm_tools::Error::NotFound) => {
+            eprintln!("Error: llvm-tools not found");
+            eprintln!("Maybe the rustup component `llvm-tools-preview` is missing?");
+            eprintln!("  Install it through: `rustup component add llvm-tools-preview`");
+            process::exit(1);
+        }
+        Err(err) => {
+            eprintln!("Failed to retrieve llvm-tools component: {:?}", err);
+            process::exit(1);
+        }
+    };
+    let objcopy = llvm_tools.tool(&llvm_tools::exe("llvm-objcopy")).expect("llvm-objcopy not found in llvm-tools");
+
+    let mut cmd = Command::new(objcopy);
+    cmd.arg("-I").arg("binary");
+    cmd.arg("-O").arg("elf64-x86-64");
+    cmd.arg("--binary-architecture=i386:x86-64");
+    cmd.arg("--rename-section").arg(".data=.kernel");
+    cmd.arg("--redefine-sym").arg(format!("_binary_{}_start=_kernel_start_addr", kernel_file_name_replaced));
+    cmd.arg("--redefine-sym").arg(format!("_binary_{}_end=_kernel_end_addr", kernel_file_name_replaced));
+    cmd.arg("--redefine-sym").arg(format!("_binary_{}_size=_kernel_size", kernel_file_name_replaced));
+    cmd.current_dir(kernel.parent().expect("KERNEL has no valid parent dir"));
+    cmd.arg(&kernel_file_name);
+    cmd.arg(&kernel_out_path);
+    let exit_status = cmd.status().expect("failed to run objcopy");
+    if !exit_status.success() {
+        eprintln!("Error: Running objcopy failed");
+        process::exit(1);
+    }
+
+    let ar = llvm_tools.tool(&llvm_tools::exe("llvm-ar")).unwrap_or_else(|| {
+        eprintln!("Failed to retrieve llvm-ar component");
+        eprint!("This component is available since nightly-XXXX-XX-XX,");
+        eprintln!("so try updating your toolchain if you're using an older nightly");
+        process::exit(1);
+    });
+    let mut cmd = Command::new(ar);
+    cmd.arg("crs");
+    cmd.arg(&kernel_archive_path);
+    cmd.arg(&kernel_out_path);
+    let exit_status = cmd.status().expect("failed to run ar");
+    if !exit_status.success() {
+        eprintln!("Error: Running ar failed");
+        process::exit(1);
+    }
+
+    println!("cargo:rerun-if-env-changed=KERNEL");
+    println!("cargo:rerun-if-changed={}", kernel.display());
+    println!("cargo:rerun-if-changed=build.rs");
+    println!("cargo:rustc-link-search=native={}", out_dir.display());
+    println!("cargo:rustc-link-lib=static=kernel_bin-{}", kernel_file_name);
+}