From db26dabd6eb803694fe51a55d7690cbd26060d2c Mon Sep 17 00:00:00 2001
From: Nathan Houghton <nathan@brainwerk.org>
Date: Sat, 21 Oct 2023 20:23:28 -0700
Subject: [PATCH] tests/dd: Do not use the OS provided dd utility on FIFOs

On *BSD and macOS, the system provided dd utility opens up the output
file for both reading and writing. This means that the open/write to the
FIFO does not block, and almost instantly completes. The system dd then
exits, leaving nothing left to be read by the time the coreutils-rs dd
tries to open/read the FIFO.

Avoid this problem by just writing to the FIFO from the test case
itself, rather than relying on the system provide dd.
---
 tests/by-util/test_dd.rs | 72 ++++++++++++----------------------------
 1 file changed, 22 insertions(+), 50 deletions(-)

diff --git a/tests/by-util/test_dd.rs b/tests/by-util/test_dd.rs
index 8ebf57c1c..f560e3526 100644
--- a/tests/by-util/test_dd.rs
+++ b/tests/by-util/test_dd.rs
@@ -15,8 +15,6 @@ use regex::Regex;
 use std::fs::{File, OpenOptions};
 use std::io::{BufReader, Read, Write};
 use std::path::PathBuf;
-#[cfg(all(unix, not(target_os = "macos"), not(target_os = "freebsd")))]
-use std::process::{Command, Stdio};
 #[cfg(not(windows))]
 use std::thread::sleep;
 #[cfg(not(windows))]
@@ -1459,74 +1457,48 @@ fn test_sparse() {
     assert_eq!(at.metadata("infile").len(), at.metadata("outfile").len());
 }
 
-// TODO These FIFO tests should work on macos, but some issue is
-// causing our implementation of dd to wait indefinitely when it
-// shouldn't.
-
 /// Test that a seek on an output FIFO results in a read.
 #[test]
-#[cfg(all(unix, not(target_os = "macos"), not(target_os = "freebsd")))]
+#[cfg(unix)]
 fn test_seek_output_fifo() {
     let ts = TestScenario::new(util_name!());
     let at = &ts.fixtures;
     at.mkfifo("fifo");
 
-    // TODO When `dd` is a bit more advanced, we could use the uutils
-    // version of dd here as well.
-    let child = Command::new("dd")
-        .current_dir(&at.subdir)
-        .args([
-            "count=1",
-            "if=/dev/zero",
-            &format!("of={}", at.plus_as_string("fifo")),
-            "status=noxfer",
-        ])
-        .stderr(Stdio::piped())
-        .spawn()
-        .expect("failed to execute child process");
-
-    ts.ucmd()
+    let mut ucmd = ts.ucmd();
+    let child = ucmd
         .args(&["count=0", "seek=1", "of=fifo", "status=noxfer"])
-        .succeeds()
-        .stderr_only("0+0 records in\n0+0 records out\n");
+        .run_no_wait();
 
-    let output = child.wait_with_output().unwrap();
-    assert!(output.status.success());
-    assert!(output.stdout.is_empty());
-    assert_eq!(&output.stderr, b"1+0 records in\n1+0 records out\n");
+    std::fs::write(at.plus("fifo"), &vec![0; 512]).unwrap();
+
+    child
+        .wait()
+        .unwrap()
+        .success()
+        .stderr_only("0+0 records in\n0+0 records out\n");
 }
 
 /// Test that a skip on an input FIFO results in a read.
 #[test]
-#[cfg(all(unix, not(target_os = "macos"), not(target_os = "freebsd")))]
+#[cfg(unix)]
 fn test_skip_input_fifo() {
     let ts = TestScenario::new(util_name!());
     let at = &ts.fixtures;
     at.mkfifo("fifo");
 
-    // TODO When `dd` is a bit more advanced, we could use the uutils
-    // version of dd here as well.
-    let child = Command::new("dd")
-        .current_dir(&at.subdir)
-        .args([
-            "count=1",
-            "if=/dev/zero",
-            &format!("of={}", at.plus_as_string("fifo")),
-            "status=noxfer",
-        ])
-        .stderr(Stdio::piped())
-        .spawn()
-        .expect("failed to execute child process");
-
-    ts.ucmd()
+    let mut ucmd = ts.ucmd();
+    let child = ucmd
         .args(&["count=0", "skip=1", "if=fifo", "status=noxfer"])
-        .succeeds()
-        .stderr_only("0+0 records in\n0+0 records out\n");
+        .run_no_wait();
 
-    let output = child.wait_with_output().unwrap();
-    assert!(output.status.success());
-    assert!(output.stdout.is_empty());
-    assert_eq!(&output.stderr, b"1+0 records in\n1+0 records out\n");
+    std::fs::write(at.plus("fifo"), &vec![0; 512]).unwrap();
+
+    child
+        .wait()
+        .unwrap()
+        .success()
+        .stderr_only("0+0 records in\n0+0 records out\n");
 }
 
 /// Test for reading part of stdin from each of two child processes.