From f9b3d6a5252e043b9a0f0347e8481a61d6b83b8b Mon Sep 17 00:00:00 2001
From: Chris Denton <chris@chrisdenton.dev>
Date: Sat, 15 Apr 2023 11:57:07 +0100
Subject: [PATCH] Generate windows-sys bindings

---
 Cargo.lock                                 | 29 +++++++++++++++++
 Cargo.toml                                 |  1 +
 src/bootstrap/builder.rs                   |  1 +
 src/bootstrap/run.rs                       | 22 +++++++++++++
 src/bootstrap/tool.rs                      |  1 +
 src/tools/generate-windows-sys/Cargo.toml  |  7 ++++
 src/tools/generate-windows-sys/src/main.rs | 37 ++++++++++++++++++++++
 7 files changed, 98 insertions(+)
 create mode 100644 src/tools/generate-windows-sys/Cargo.toml
 create mode 100644 src/tools/generate-windows-sys/src/main.rs

diff --git a/Cargo.lock b/Cargo.lock
index 8e71d8ceac8..bd5af7b409a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1443,6 +1443,13 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "generate-windows-sys"
+version = "0.1.0"
+dependencies = [
+ "windows-bindgen",
+]
+
 [[package]]
 name = "generic-array"
 version = "0.14.4"
@@ -5505,6 +5512,22 @@ dependencies = [
  "windows-targets 0.48.0",
 ]
 
+[[package]]
+name = "windows-bindgen"
+version = "0.49.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6935fb09b84ee57929ae92518b475f5dfdfbeb87c5334756acc28ee8e202b60"
+dependencies = [
+ "windows-metadata",
+ "windows-tokens",
+]
+
+[[package]]
+name = "windows-metadata"
+version = "0.49.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f5bca94a32bf1e6a376522b6601275a3b611ee885ec0f1b6a05f17e8cfd3385"
+
 [[package]]
 name = "windows-sys"
 version = "0.42.0"
@@ -5568,6 +5591,12 @@ dependencies = [
  "windows_x86_64_msvc 0.48.0",
 ]
 
+[[package]]
+name = "windows-tokens"
+version = "0.48.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b34c9a3b28cb41db7385546f7f9a8179348dffc89923dde66857b1ba5312f6b4"
+
 [[package]]
 name = "windows_aarch64_gnullvm"
 version = "0.42.2"
diff --git a/Cargo.toml b/Cargo.toml
index 7aaa34a68e6..53331e2869f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -39,6 +39,7 @@ members = [
   "src/tools/collect-license-metadata",
   "src/tools/generate-copyright",
   "src/tools/suggest-tests",
+  "src/tools/generate-windows-sys",
 ]
 
 exclude = [
diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index d9d4685dfc7..2cc89117ae5 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -832,6 +832,7 @@ macro_rules! describe {
                 run::Miri,
                 run::CollectLicenseMetadata,
                 run::GenerateCopyright,
+                run::GenerateWindowsSys,
             ),
             Kind::Setup => describe!(setup::Profile, setup::Hook, setup::Link, setup::Vscode),
             Kind::Clean => describe!(clean::CleanAll, clean::Rustc, clean::Std),
diff --git a/src/bootstrap/run.rs b/src/bootstrap/run.rs
index cb15d9a6325..57f3119e322 100644
--- a/src/bootstrap/run.rs
+++ b/src/bootstrap/run.rs
@@ -253,3 +253,25 @@ fn run(self, builder: &Builder<'_>) -> Self::Output {
         dest
     }
 }
+
+#[derive(Debug, PartialOrd, Ord, Copy, Clone, Hash, PartialEq, Eq)]
+pub struct GenerateWindowsSys;
+
+impl Step for GenerateWindowsSys {
+    type Output = ();
+    const ONLY_HOSTS: bool = true;
+
+    fn should_run(run: ShouldRun<'_>) -> ShouldRun<'_> {
+        run.path("src/tools/generate-windows-sys")
+    }
+
+    fn make_run(run: RunConfig<'_>) {
+        run.builder.ensure(GenerateWindowsSys);
+    }
+
+    fn run(self, builder: &Builder<'_>) {
+        let mut cmd = builder.tool_cmd(Tool::GenerateWindowsSys);
+        cmd.arg(&builder.src);
+        builder.run(&mut cmd);
+    }
+}
diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index 39f6369b4d3..f13d365e375 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -301,6 +301,7 @@ fn run(self, builder: &Builder<'_>) -> PathBuf {
     CollectLicenseMetadata, "src/tools/collect-license-metadata", "collect-license-metadata";
     GenerateCopyright, "src/tools/generate-copyright", "generate-copyright";
     SuggestTests, "src/tools/suggest-tests", "suggest-tests";
+    GenerateWindowsSys, "src/tools/generate-windows-sys", "generate-windows-sys";
 );
 
 #[derive(Debug, Copy, Clone, Hash, PartialEq, Eq, Ord, PartialOrd)]
diff --git a/src/tools/generate-windows-sys/Cargo.toml b/src/tools/generate-windows-sys/Cargo.toml
new file mode 100644
index 00000000000..23e88844bd0
--- /dev/null
+++ b/src/tools/generate-windows-sys/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "generate-windows-sys"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies.windows-bindgen]
+version = "0.49"
diff --git a/src/tools/generate-windows-sys/src/main.rs b/src/tools/generate-windows-sys/src/main.rs
new file mode 100644
index 00000000000..0b091b1ebfa
--- /dev/null
+++ b/src/tools/generate-windows-sys/src/main.rs
@@ -0,0 +1,37 @@
+use std::fs;
+use std::io::{self, Write};
+use std::path::PathBuf;
+
+/// This is printed to the file before the rest of the contents.
+const PRELUDE: &str = r#"// This file is autogenerated.
+//
+// To add bindings, edit windows_sys.lst then use `./x run generate-windows-sys` to
+// regenerate the bindings.
+//
+// ignore-tidy-filelength
+"#;
+
+fn main() -> io::Result<()> {
+    let mut path: PathBuf =
+        std::env::args_os().nth(1).expect("a path to the rust repository is required").into();
+    path.push("library/std/src/sys/windows/c/windows_sys.lst");
+
+    // Load the list of APIs
+    let buffer = fs::read_to_string(&path)?;
+    let names: Vec<&str> = buffer
+        .lines()
+        .filter_map(|line| {
+            let line = line.trim();
+            if line.is_empty() || line.starts_with('#') { None } else { Some(line) }
+        })
+        .collect();
+
+    // Write the bindings to windows-sys.rs
+    let bindings = windows_bindgen::standalone_std(&names);
+    path.set_extension("rs");
+    let mut f = std::fs::File::create(&path)?;
+    f.write_all(PRELUDE.as_bytes())?;
+    f.write_all(bindings.as_bytes())?;
+
+    Ok(())
+}