refactor: remove create_dir_all_threadsafe helper

as std::fs::create_dir_all is now threadsafe

rust-lang/rust#39799

src/util.rs

@@ -5,7 +5,7 @@ use std::os::unix::process::ExitStatusExt;
 use std::{
     cmp::min,
     env, fs,
-    fs::File,
+    fs::{create_dir_all, File},
     io::{BufRead, BufReader, BufWriter, Read, Write},
     path::{Path, PathBuf},
     str,
@@ -724,30 +724,6 @@ pub fn range(start: Idx, end: Idx, len: Idx, index: Idx) -> Result<(usize, usize
     }
 }
 
-/// Create a directory recursively, avoiding the race conditions fixed by
-/// https://github.com/rust-lang/rust/pull/39799.
-#[cfg(any(feature = "feature_capable", feature = "lite"))]
-fn create_dir_all_threadsafe(path: &Path) -> std::io::Result<()> {
-    use std::thread;
-
-    // Try 20 times. This shouldn't theoretically need to be any larger
-    // than the number of nested directories we need to create.
-    for _ in 0..20 {
-        match fs::create_dir_all(path) {
-            // This happens if a directory in `path` doesn't exist when we
-            // test for it, and another thread creates it before we can.
-            Err(ref err) if err.kind() == std::io::ErrorKind::AlreadyExists => {},
-            other => return other,
-        }
-        // We probably don't need to sleep at all, because the intermediate
-        // directory is already created.  But let's attempt to back off a
-        // bit and let the other thread finish.
-        thread::sleep(std::time::Duration::from_millis(25));
-    }
-    // Try one last time, returning whatever happens.
-    fs::create_dir_all(path)
-}
-
 /// Represents a filename template of the form `"{}.csv"`, where `"{}"` is
 /// the place to insert the part of the filename generated by `qsv`.
 #[cfg(any(feature = "feature_capable", feature = "lite"))]
@@ -783,7 +759,7 @@ impl FilenameTemplate {
             // We may be called concurrently, especially by parallel `qsv
             // split`, so be careful to avoid the `create_dir_all` race
             // condition.
-            create_dir_all_threadsafe(parent)?;
+            create_dir_all(parent)?;
         }
         let spath = Some(full_path.display().to_string());
         Config::new(spath.as_ref()).writer()