Merge commit 'e9d1a0a7b0' into sync_cg_clif-2022-08-24

compiler/rustc_codegen_cranelift/build_system/utils.rs

@@ -1,6 +1,8 @@
+use std::env;
 use std::fs;
+use std::io::Write;
 use std::path::Path;
-use std::process::{self, Command};
+use std::process::{self, Command, Stdio};
 
 #[track_caller]
 pub(crate) fn try_hard_link(src: impl AsRef<Path>, dst: impl AsRef<Path>) {
@@ -18,6 +20,27 @@ pub(crate) fn spawn_and_wait(mut cmd: Command) {
     }
 }
 
+#[track_caller]
+pub(crate) fn spawn_and_wait_with_input(mut cmd: Command, input: String) -> String {
+    let mut child = cmd
+        .stdin(Stdio::piped())
+        .stdout(Stdio::piped())
+        .spawn()
+        .expect("Failed to spawn child process");
+
+    let mut stdin = child.stdin.take().expect("Failed to open stdin");
+    std::thread::spawn(move || {
+        stdin.write_all(input.as_bytes()).expect("Failed to write to stdin");
+    });
+
+    let output = child.wait_with_output().expect("Failed to read stdout");
+    if !output.status.success() {
+        process::exit(1);
+    }
+
+    String::from_utf8(output.stdout).unwrap()
+}
+
 pub(crate) fn copy_dir_recursively(from: &Path, to: &Path) {
     for entry in fs::read_dir(from).unwrap() {
         let entry = entry.unwrap();
@@ -33,3 +56,7 @@ pub(crate) fn copy_dir_recursively(from: &Path, to: &Path) {
         }
     }
 }
+
+pub(crate) fn is_ci() -> bool {
+    env::var("CI").as_ref().map(|val| &**val) == Ok("true")
+}