fix(compile): atomically write compile output (denoland#24378)

Atomically write `deno compile` output file so we won't get a partially
written ELF/PE file, and prevents corrupting running processes.

cli/tools/compile.rs

@@ -12,6 +12,7 @@ use deno_core::error::AnyError;
 use deno_core::resolve_url_or_path;
 use deno_graph::GraphKind;
 use deno_terminal::colors;
+use rand::Rng;
 use std::path::Path;
 use std::path::PathBuf;
 use std::sync::Arc;
@@ -97,8 +98,20 @@ pub async fn compile(
  );
  validate_output_path(&output_path)?;
 
- let mut file = std::fs::File::create(&output_path)
- .with_context(|| format!("Opening file '{}'", output_path.display()))?;
+ let mut temp_filename = output_path.file_name().unwrap().to_owned();
+ temp_filename.push(format!(
+ ".tmp-{}",
+ faster_hex::hex_encode(
+ &rand::thread_rng().gen::<[u8; 8]>(),
+ &mut [0u8; 16]
+ )
+ .unwrap()
+ ));
+ let temp_path = output_path.with_file_name(temp_filename);
+
+ let mut file = std::fs::File::create(&temp_path).with_context(|| {
+ format!("Opening temporary file '{}'", temp_path.display())
+ })?;
  let write_result = binary_writer
  .write_bin(
  &mut file,
@@ -108,20 +121,38 @@ pub async fn compile(
  cli_options,
  )
  .await
- .with_context(|| format!("Writing {}", output_path.display()));
+ .with_context(|| {
+ format!("Writing temporary file '{}'", temp_path.display())
+ });
  drop(file);
- if let Err(err) = write_result {
- // errored, so attempt to remove the output path
- let _ = std::fs::remove_file(output_path);
- return Err(err);
- }
 
  // set it as executable
  #[cfg(unix)]
- {
+ let write_result = write_result.and_then(|_| {
  use std::os::unix::fs::PermissionsExt;
- let perms = std::fs::Permissions::from_mode(0o777);
- std::fs::set_permissions(output_path, perms)?;
+ let perms = std::fs::Permissions::from_mode(0o755);
+ std::fs::set_permissions(&temp_path, perms).with_context(|| {
+ format!(
+ "Setting permissions on temporary file '{}'",
+ temp_path.display()
+ )
+ })
+ });
+
+ let write_result = write_result.and_then(|_| {
+ std::fs::rename(&temp_path, &output_path).with_context(|| {
+ format!(
+ "Renaming temporary file '{}' to '{}'",
+ temp_path.display(),
+ output_path.display()
+ )
+ })
+ });
+
+ if let Err(err) = write_result {
+ // errored, so attempt to remove the temporary file
+ let _ = std::fs::remove_file(temp_path);
+ return Err(err);
  }
 
  Ok(())