1 files changed, 240 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_gcc/build_system/src/utils.rs b/compiler/rustc_codegen_gcc/build_system/src/utils.rs
new file mode 100644
index 00000000000..536f33a8029
--- /dev/null
+++ b/compiler/rustc_codegen_gcc/build_system/src/utils.rs
@@ -0,0 +1,240 @@
+use std::collections::HashMap;
+use std::ffi::OsStr;
+use std::fmt::Debug;
+use std::fs;
+use std::path::Path;
+use std::process::{Command, ExitStatus, Output};
+
+fn get_command_inner(
+    input: &[&dyn AsRef<OsStr>],
+    cwd: Option<&Path>,
+    env: Option<&HashMap<String, String>>,
+) -> Command {
+    let (cmd, args) = match input {
+        [] => panic!("empty command"),
+        [cmd, args @ ..] => (cmd, args),
+    };
+    let mut command = Command::new(cmd);
+    command.args(args);
+    if let Some(cwd) = cwd {
+        command.current_dir(cwd);
+    }
+    if let Some(env) = env {
+        command.envs(env.iter().map(|(k, v)| (k.as_str(), v.as_str())));
+    }
+    command
+}
+
+fn check_exit_status(
+    input: &[&dyn AsRef<OsStr>],
+    cwd: Option<&Path>,
+    exit_status: ExitStatus,
+) -> Result<(), String> {
+    if exit_status.success() {
+        Ok(())
+    } else {
+        Err(format!(
+            "Command `{}`{} exited with status {:?}",
+            input
+                .iter()
+                .map(|s| s.as_ref().to_str().unwrap())
+                .collect::<Vec<_>>()
+                .join(" "),
+            cwd.map(|cwd| format!(" (running in folder `{}`)", cwd.display()))
+                .unwrap_or_default(),
+            exit_status.code(),
+        ))
+    }
+}
+
+fn command_error<D: Debug>(input: &[&dyn AsRef<OsStr>], cwd: &Option<&Path>, error: D) -> String {
+    format!(
+        "Command `{}`{} failed to run: {error:?}",
+        input
+            .iter()
+            .map(|s| s.as_ref().to_str().unwrap())
+            .collect::<Vec<_>>()
+            .join(" "),
+        cwd.as_ref()
+            .map(|cwd| format!(" (running in folder `{}`)", cwd.display(),))
+            .unwrap_or_default(),
+    )
+}
+
+pub fn run_command(input: &[&dyn AsRef<OsStr>], cwd: Option<&Path>) -> Result<Output, String> {
+    run_command_with_env(input, cwd, None)
+}
+
+pub fn run_command_with_env(
+    input: &[&dyn AsRef<OsStr>],
+    cwd: Option<&Path>,
+    env: Option<&HashMap<String, String>>,
+) -> Result<Output, String> {
+    let output = get_command_inner(input, cwd, env)
+        .output()
+        .map_err(|e| command_error(input, &cwd, e))?;
+    check_exit_status(input, cwd, output.status)?;
+    Ok(output)
+}
+
+pub fn run_command_with_output(
+    input: &[&dyn AsRef<OsStr>],
+    cwd: Option<&Path>,
+) -> Result<(), String> {
+    let exit_status = get_command_inner(input, cwd, None)
+        .spawn()
+        .map_err(|e| command_error(input, &cwd, e))?
+        .wait()
+        .map_err(|e| command_error(input, &cwd, e))?;
+    check_exit_status(input, cwd, exit_status)?;
+    Ok(())
+}
+
+pub fn run_command_with_output_and_env(
+    input: &[&dyn AsRef<OsStr>],
+    cwd: Option<&Path>,
+    env: Option<&HashMap<String, String>>,
+) -> Result<(), String> {
+    let exit_status = get_command_inner(input, cwd, env)
+        .spawn()
+        .map_err(|e| command_error(input, &cwd, e))?
+        .wait()
+        .map_err(|e| command_error(input, &cwd, e))?;
+    check_exit_status(input, cwd, exit_status)?;
+    Ok(())
+}
+
+pub fn cargo_install(to_install: &str) -> Result<(), String> {
+    let output = run_command(&[&"cargo", &"install", &"--list"], None)?;
+
+    let to_install_needle = format!("{to_install} ");
+    // cargo install --list returns something like this:
+    //
+    // mdbook-toc v0.8.0:
+    //     mdbook-toc
+    // rust-reduce v0.1.0:
+    //     rust-reduce
+    //
+    // We are only interested into the command name so we only look for lines ending with `:`.
+    if String::from_utf8(output.stdout)
+        .unwrap()
+        .lines()
+        .any(|line| line.ends_with(':') && line.starts_with(&to_install_needle))
+    {
+        return Ok(());
+    }
+    // We voluntarily ignore this error.
+    if run_command_with_output(&[&"cargo", &"install", &to_install], None).is_err() {
+        println!("Skipping installation of `{to_install}`");
+    }
+    Ok(())
+}
+
+pub fn get_os_name() -> Result<String, String> {
+    let output = run_command(&[&"uname"], None)?;
+    let name = std::str::from_utf8(&output.stdout)
+        .unwrap_or("")
+        .trim()
+        .to_string();
+    if !name.is_empty() {
+        Ok(name)
+    } else {
+        Err("Failed to retrieve the OS name".to_string())
+    }
+}
+
+pub fn get_rustc_host_triple() -> Result<String, String> {
+    let output = run_command(&[&"rustc", &"-vV"], None)?;
+    let content = std::str::from_utf8(&output.stdout).unwrap_or("");
+
+    for line in content.split('\n').map(|line| line.trim()) {
+        if !line.starts_with("host:") {
+            continue;
+        }
+        return Ok(line.split(':').nth(1).unwrap().trim().to_string());
+    }
+    Err("Cannot find host triple".to_string())
+}
+
+pub fn get_gcc_path() -> Result<String, String> {
+    let content = match fs::read_to_string("gcc_path") {
+        Ok(content) => content,
+        Err(_) => {
+            return Err(
+                "Please put the path to your custom build of libgccjit in the file \
+                   `gcc_path`, see Readme.md for details"
+                    .into(),
+            )
+        }
+    };
+    match content
+        .split('\n')
+        .map(|line| line.trim())
+        .filter(|line| !line.is_empty())
+        .next()
+    {
+        Some(gcc_path) => {
+            let path = Path::new(gcc_path);
+            if !path.exists() {
+                Err(format!(
+                    "Path `{}` contained in the `gcc_path` file doesn't exist",
+                    gcc_path,
+                ))
+            } else {
+                Ok(gcc_path.into())
+            }
+        }
+        None => Err("No path found in `gcc_path` file".into()),
+    }
+}
+
+pub struct CloneResult {
+    pub ran_clone: bool,
+    pub repo_name: String,
+}
+
+pub fn git_clone(to_clone: &str, dest: Option<&Path>) -> Result<CloneResult, String> {
+    let repo_name = to_clone.split('/').last().unwrap();
+    let repo_name = match repo_name.strip_suffix(".git") {
+        Some(n) => n.to_string(),
+        None => repo_name.to_string(),
+    };
+
+    let dest = dest
+        .map(|dest| dest.join(&repo_name))
+        .unwrap_or_else(|| Path::new(&repo_name).into());
+    if dest.is_dir() {
+        return Ok(CloneResult {
+            ran_clone: false,
+            repo_name,
+        });
+    }
+
+    run_command_with_output(&[&"git", &"clone", &to_clone, &dest], None)?;
+    Ok(CloneResult {
+        ran_clone: true,
+        repo_name,
+    })
+}
+
+pub fn walk_dir<P, D, F>(dir: P, mut dir_cb: D, mut file_cb: F) -> Result<(), String>
+where
+    P: AsRef<Path>,
+    D: FnMut(&Path) -> Result<(), String>,
+    F: FnMut(&Path) -> Result<(), String>,
+{
+    let dir = dir.as_ref();
+    for entry in fs::read_dir(dir)
+        .map_err(|error| format!("Failed to read dir `{}`: {:?}", dir.display(), error))?
+    {
+        let entry = entry
+            .map_err(|error| format!("Failed to read entry in `{}`: {:?}", dir.display(), error))?;
+        let entry_path = entry.path();
+        if entry_path.is_dir() {
+            dir_cb(&entry_path)?;
+        } else {
+            file_cb(&entry_path)?;
+        }
+    }
+    Ok(())
+}