Merge commit '98ed962c7d' into master

compiler/rustc_codegen_gcc/build_system/src/rust_tools.rs

@@ -0,0 +1,125 @@
+use crate::config::ConfigInfo;
+use crate::utils::{
+    get_toolchain, run_command_with_output_and_env_no_err, rustc_toolchain_version_info,
+    rustc_version_info,
+};
+
+use std::collections::HashMap;
+use std::ffi::OsStr;
+use std::path::PathBuf;
+
+fn args(command: &str) -> Result<Option<Vec<String>>, String> {
+    // We skip the binary and the "cargo"/"rustc" option.
+    if let Some("--help") = std::env::args().skip(2).next().as_deref() {
+        usage(command);
+        return Ok(None);
+    }
+    let args = std::env::args().skip(2).collect::<Vec<_>>();
+    if args.is_empty() {
+        return Err(format!(
+            "Expected at least one argument for `{}` subcommand, found none",
+            command
+        ));
+    }
+    Ok(Some(args))
+}
+
+fn usage(command: &str) {
+    println!(
+        r#"
+`{}` command help:
+
+    [args]     : Arguments to be passed to the cargo command
+    --help     : Show this help
+"#,
+        command,
+    )
+}
+
+struct RustcTools {
+    env: HashMap<String, String>,
+    args: Vec<String>,
+    toolchain: String,
+    config: ConfigInfo,
+}
+
+impl RustcTools {
+    fn new(command: &str) -> Result<Option<Self>, String> {
+        let Some(args) = args(command)? else { return Ok(None) };
+
+        // We first need to go to the original location to ensure that the config setup will go as
+        // expected.
+        let current_dir = std::env::current_dir()
+            .and_then(|path| path.canonicalize())
+            .map_err(|error| format!("Failed to get current directory path: {:?}", error))?;
+        let current_exe = std::env::current_exe()
+            .and_then(|path| path.canonicalize())
+            .map_err(|error| format!("Failed to get current exe path: {:?}", error))?;
+        let mut parent_dir =
+            current_exe.components().map(|comp| comp.as_os_str()).collect::<Vec<_>>();
+        // We run this script from "build_system/target/release/y", so we need to remove these elements.
+        for to_remove in &["y", "release", "target", "build_system"] {
+            if parent_dir.last().map(|part| part == to_remove).unwrap_or(false) {
+                parent_dir.pop();
+            } else {
+                return Err(format!(
+                    "Build script not executed from `build_system/target/release/y` (in path {})",
+                    current_exe.display(),
+                ));
+            }
+        }
+        let parent_dir = PathBuf::from(parent_dir.join(&OsStr::new("/")));
+        std::env::set_current_dir(&parent_dir).map_err(|error| {
+            format!("Failed to go to `{}` folder: {:?}", parent_dir.display(), error)
+        })?;
+
+        let mut env: HashMap<String, String> = std::env::vars().collect();
+        let mut config = ConfigInfo::default();
+        config.setup(&mut env, false)?;
+        let toolchain = get_toolchain()?;
+
+        let toolchain_version = rustc_toolchain_version_info(&toolchain)?;
+        let default_version = rustc_version_info(None)?;
+        if toolchain_version != default_version {
+            println!(
+                "rustc_codegen_gcc is built for {} but the default rustc version is {}.",
+                toolchain_version.short, default_version.short,
+            );
+            println!("Using {}.", toolchain_version.short);
+        }
+
+        // We go back to the original folder since we now have set up everything we needed.
+        std::env::set_current_dir(&current_dir).map_err(|error| {
+            format!("Failed to go back to `{}` folder: {:?}", current_dir.display(), error)
+        })?;
+        let toolchain = format!("+{}", toolchain);
+        Ok(Some(Self { toolchain, args, env, config }))
+    }
+}
+
+pub fn run_cargo() -> Result<(), String> {
+    let Some(mut tools) = RustcTools::new("cargo")? else { return Ok(()) };
+    let rustflags = tools.env.get("RUSTFLAGS").cloned().unwrap_or_default();
+    tools.env.insert("RUSTDOCFLAGS".to_string(), rustflags);
+    let mut command: Vec<&dyn AsRef<OsStr>> = vec![&"cargo", &tools.toolchain];
+    for arg in &tools.args {
+        command.push(arg);
+    }
+    if run_command_with_output_and_env_no_err(&command, None, Some(&tools.env)).is_err() {
+        std::process::exit(1);
+    }
+
+    Ok(())
+}
+
+pub fn run_rustc() -> Result<(), String> {
+    let Some(tools) = RustcTools::new("rustc")? else { return Ok(()) };
+    let mut command = tools.config.rustc_command_vec();
+    for arg in &tools.args {
+        command.push(arg);
+    }
+    if run_command_with_output_and_env_no_err(&command, None, Some(&tools.env)).is_err() {
+        std::process::exit(1);
+    }
+    Ok(())
+}