workspace: add Rust EFI infrastructure
This bumps rules_rust, cleans up the toolchains with the new version.
It also adds the Prost codegen to "normal" crate set as well as a new
crate set specific to EFI. This is separate because of Rust no-std's
dependence on create feature tags.
Change-Id: Ie76e66ee83696948391420ca3b011a3a71258690
Reviewed-on: https://review.monogon.dev/c/monogon/+/2202
Tested-by: Jenkins CI
Reviewed-by: Serge Bazanski <serge@monogon.tech>
diff --git a/third_party/rust-prost-nostd.patch b/third_party/rust-prost-nostd.patch
new file mode 100644
index 0000000..71c2058
--- /dev/null
+++ b/third_party/rust-prost-nostd.patch
@@ -0,0 +1,123 @@
+From 8cc9584796b41c3b5c9d213b751de9762963ebbf Mon Sep 17 00:00:00 2001
+From: Lorenz Brun <lorenz@monogon.tech>
+Date: Mon, 2 Oct 2023 15:35:38 +0200
+Subject: [PATCH] Support no_std in Prost toolchain
+
+---
+ proto/prost/private/prost.bzl | 8 ++++++++
+ proto/prost/private/protoc_wrapper.rs | 17 ++++++++++++++---
+ 2 files changed, 22 insertions(+), 3 deletions(-)
+
+diff --git a/proto/prost/private/prost.bzl b/proto/prost/private/prost.bzl
+index 6cd3d522..ae7ead91 100644
+--- a/proto/prost/private/prost.bzl
++++ b/proto/prost/private/prost.bzl
+@@ -64,6 +64,9 @@ def _compile_proto(ctx, crate_name, proto_info, deps, prost_toolchain, rustfmt_t
+ additional_args.add("--descriptor_set={}".format(proto_info.direct_descriptor_set.path))
+ additional_args.add_all(prost_toolchain.prost_opts, format_each = "--prost_opt=%s")
+
++ if prost_toolchain.is_nostd:
++ additional_args.add("--is_nostd")
++
+ if prost_toolchain.tonic_plugin:
+ tonic_plugin = prost_toolchain.tonic_plugin[DefaultInfo].files_to_run
+ additional_args.add(prost_toolchain.tonic_plugin_flag % tonic_plugin.executable.path)
+@@ -371,6 +374,7 @@ def _rust_prost_toolchain_impl(ctx):
+ tonic_plugin = ctx.attr.tonic_plugin,
+ tonic_plugin_flag = ctx.attr.tonic_plugin_flag,
+ tonic_runtime = ctx.attr.tonic_runtime,
++ is_nostd = ctx.attr.is_nostd,
+ )]
+
+ rust_prost_toolchain = rule(
+@@ -423,6 +427,10 @@ rust_prost_toolchain = rule(
+ doc = "The Tonic runtime crates to use.",
+ providers = [[rust_common.crate_info], [rust_common.crate_group_info]],
+ ),
++ "is_nostd": attr.bool(
++ doc = "If a no_std tag should be put into the generated code.",
++ default = False,
++ ),
+ },
+ )
+
+diff --git a/proto/prost/private/protoc_wrapper.rs b/proto/prost/private/protoc_wrapper.rs
+index eb0c3319..716ba211 100644
+--- a/proto/prost/private/protoc_wrapper.rs
++++ b/proto/prost/private/protoc_wrapper.rs
+@@ -116,7 +116,7 @@ struct Module {
+ /// }
+ /// }
+ /// ```
+-fn generate_lib_rs(prost_outputs: &BTreeSet<PathBuf>, is_tonic: bool) -> String {
++fn generate_lib_rs(prost_outputs: &BTreeSet<PathBuf>, is_tonic: bool, is_nostd: bool) -> String {
+ let mut module_info = BTreeMap::new();
+
+ for path in prost_outputs.iter() {
+@@ -188,7 +188,8 @@ fn generate_lib_rs(prost_outputs: &BTreeSet<PathBuf>, is_tonic: bool) -> String
+ }
+ }
+
+- let mut content = "// @generated\n\n".to_string();
++ let mut content = if is_nostd { "#![no_std]\n".to_string() } else { "".to_string() };
++ content.push_str(&"// @generated\n\n");
+ write_module(&mut content, &module_info, "", 0);
+ content
+ }
+@@ -442,6 +443,9 @@ struct Args {
+ /// Whether to generate tonic code.
+ is_tonic: bool,
+
++ // Whether to put a no_std tag into the generated code.
++ is_nostd: bool,
++
+ /// Extra arguments to pass to protoc.
+ extra_args: Vec<String>,
+ }
+@@ -462,6 +466,7 @@ impl Args {
+ let mut label: Option<String> = None;
+ let mut tonic_or_prost_opts = Vec::new();
+ let mut is_tonic = false;
++ let mut is_nostd = false;
+
+ let mut extra_args = Vec::new();
+
+@@ -487,6 +492,10 @@ impl Args {
+ is_tonic = true;
+ continue;
+ }
++ if arg == "--is_nostd" {
++ is_nostd = true;
++ continue;
++ }
+
+ if !arg.contains('=') {
+ extra_args.push(arg);
+@@ -599,6 +608,7 @@ impl Args {
+ rustfmt,
+ proto_paths,
+ is_tonic,
++ is_nostd,
+ label: label.unwrap(),
+ extra_args,
+ })
+@@ -704,6 +714,7 @@ fn main() {
+ rustfmt,
+ proto_paths,
+ is_tonic,
++ is_nostd,
+ extra_args,
+ } = Args::parse().expect("Failed to parse args");
+
+@@ -816,7 +827,7 @@ fn main() {
+ .expect("Failed to compute proto package info");
+
+ // Write outputs
+- fs::write(&out_librs, generate_lib_rs(&rust_files, is_tonic)).expect("Failed to write file.");
++ fs::write(&out_librs, generate_lib_rs(&rust_files, is_tonic, is_nostd)).expect("Failed to write file.");
+ fs::write(
+ package_info_file,
+ extern_paths
+--
+2.41.0
+