dd: move tests of slow reader to test_dd.rs

Move some tests that simulate a slow reader from `dd.rs` to
`tests/by-util/test_dd.rs`, and employ a FIFO and `sleep()` to
simulate the slow reader instead of a custom struct that implements
`Read`. This change restricts the type of `Input`s the
`Output::dd_out()` function can accept, facilitating a future change
to make `Input` an enum.

src/uu/dd/src/dd.rs

@@ -817,27 +817,10 @@ pub fn uu_app() -> Command {
 
 #[cfg(test)]
 mod tests {
-    use crate::datastructures::{IConvFlags, IFlags};
+    use crate::{calc_bsize, Output, Parser};
-    use crate::{calc_bsize, Density, Dest, Input, Output, Parser, Settings};
 
-    use std::cmp;
-    use std::fs;
-    use std::fs::File;
-    use std::io;
-    use std::io::{BufReader, Read};
     use std::path::Path;
 
-    struct LazyReader<R: Read> {
-        src: R,
-    }
-
-    impl<R: Read> Read for LazyReader<R> {
-        fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-            let reduced = cmp::max(buf.len() / 2, 1);
-            self.src.read(&mut buf[..reduced])
-        }
-    }
-
     #[test]
     fn bsize_test_primes() {
         let (n, m) = (7901, 7919);
@@ -916,107 +899,4 @@ mod tests {
             Output::new_file(Path::new(settings.outfile.as_ref().unwrap()), &settings).is_err()
         );
     }
-
-    #[test]
-    fn test_deadbeef_16_delayed() {
-        let settings = Settings {
-            ibs: 16,
-            obs: 32,
-            count: None,
-            iconv: IConvFlags {
-                sync: Some(0),
-                ..Default::default()
-            },
-            ..Default::default()
-        };
-        let input = Input {
-            src: LazyReader {
-                src: File::open("./test-resources/deadbeef-16.test").unwrap(),
-            },
-            settings: &settings,
-        };
-
-        let output = Output {
-            dst: Dest::File(
-                File::create("./test-resources/FAILED-deadbeef-16-delayed.test").unwrap(),
-                Density::Dense,
-            ),
-            settings: &settings,
-        };
-
-        output.dd_out(input).unwrap();
-
-        let tmp_fname = "./test-resources/FAILED-deadbeef-16-delayed.test";
-        let spec = File::open("./test-resources/deadbeef-16.spec").unwrap();
-
-        let res = File::open(tmp_fname).unwrap();
-        // Check test file isn't empty (unless spec file is too)
-        assert_eq!(
-            res.metadata().unwrap().len(),
-            spec.metadata().unwrap().len()
-        );
-
-        let spec = BufReader::new(spec);
-        let res = BufReader::new(res);
-
-        // Check all bytes match
-        for (b_res, b_spec) in res.bytes().zip(spec.bytes()) {
-            assert_eq!(b_res.unwrap(), b_spec.unwrap());
-        }
-
-        fs::remove_file(tmp_fname).unwrap();
-    }
-
-    #[test]
-    fn test_random_73k_test_lazy_fullblock() {
-        let settings = Settings {
-            ibs: 521,
-            obs: 1031,
-            count: None,
-            iflags: IFlags {
-                fullblock: true,
-                ..IFlags::default()
-            },
-            ..Default::default()
-        };
-        let input = Input {
-            src: LazyReader {
-                src: File::open("./test-resources/random-5828891cb1230748e146f34223bbd3b5.test")
-                    .unwrap(),
-            },
-            settings: &settings,
-        };
-
-        let output = Output {
-            dst: Dest::File(
-                File::create("./test-resources/FAILED-random_73k_test_lazy_fullblock.test")
-                    .unwrap(),
-                Density::Dense,
-            ),
-            settings: &settings,
-        };
-
-        output.dd_out(input).unwrap();
-
-        let tmp_fname = "./test-resources/FAILED-random_73k_test_lazy_fullblock.test";
-        let spec =
-            File::open("./test-resources/random-5828891cb1230748e146f34223bbd3b5.test").unwrap();
-
-        let res = File::open(tmp_fname).unwrap();
-        // Check test file isn't empty (unless spec file is too)
-        assert_eq!(
-            res.metadata().unwrap().len(),
-            spec.metadata().unwrap().len()
-        );
-
-        let spec = BufReader::new(spec);
-        let res = BufReader::new(res);
-
-        // Check all bytes match
-        for (b_res, b_spec) in res.bytes().zip(spec.bytes()) {
-            assert_eq!(b_res.unwrap(), b_spec.unwrap());
-        }
-
-        fs::remove_file(tmp_fname).unwrap();
-    }
 }

src/uu/dd/test-resources/deadbeef-16.test

@@ -1 +0,0 @@
-<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>

tests/by-util/test_dd.rs

@@ -5,6 +5,10 @@ use crate::common::util::*;
 use std::fs::{File, OpenOptions};
 use std::io::{BufReader, Read, Write};
 use std::path::PathBuf;
+#[cfg(not(windows))]
+use std::thread::sleep;
+#[cfg(not(windows))]
+use std::time::Duration;
 use tempfile::tempfile;
 
 macro_rules! inf {
@@ -1007,6 +1011,38 @@ fn test_random_73k_test_obs_lt_not_a_multiple_ibs() {
         .stdout_is_fixture_bytes("random-5828891cb1230748e146f34223bbd3b5.test");
 }
 
+#[cfg(not(windows))]
+#[test]
+fn test_random_73k_test_lazy_fullblock() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    at.mkfifo("fifo");
+    let child = ucmd
+        .args(&[
+            "ibs=521",
+            "obs=1031",
+            "iflag=fullblock",
+            "if=fifo",
+            "status=noxfer",
+        ])
+        .run_no_wait();
+    let data = at.read_bytes("random-5828891cb1230748e146f34223bbd3b5.test");
+    {
+        let mut fifo = OpenOptions::new()
+            .write(true)
+            .open(at.plus("fifo"))
+            .unwrap();
+        for chunk in data.chunks(521 / 2) {
+            fifo.write_all(chunk).unwrap();
+            sleep(Duration::from_millis(10));
+        }
+    }
+    let output = child.wait_with_output().unwrap();
+    assert!(output.status.success());
+
+    assert_eq!(&output.stdout, &data);
+    assert_eq!(&output.stderr, b"142+1 records in\n72+1 records out\n");
+}
+
 #[test]
 fn test_deadbeef_all_32k_test_count_reads() {
     new_ucmd!()
@@ -1325,3 +1361,36 @@ fn test_bytes_suffix() {
         .succeeds()
         .stdout_only("\0\0\0abcdef");
 }
+
+/// Test for "conv=sync" with a slow reader.
+#[cfg(not(windows))]
+#[test]
+fn test_sync_delayed_reader() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    at.mkfifo("fifo");
+    let child = ucmd
+        .args(&["ibs=16", "obs=32", "conv=sync", "if=fifo", "status=noxfer"])
+        .run_no_wait();
+    {
+        let mut fifo = OpenOptions::new()
+            .write(true)
+            .open(at.plus("fifo"))
+            .unwrap();
+        for _ in 0..8 {
+            fifo.write_all(&[0xF; 8]).unwrap();
+            sleep(Duration::from_millis(10));
+        }
+    }
+    let output = child.wait_with_output().unwrap();
+    assert!(output.status.success());
+
+    // Expected output is 0xFFFFFFFF00000000FFFFFFFF00000000...
+    let mut expected: [u8; 8 * 16] = [0; 8 * 16];
+    for i in 0..8 {
+        for j in 0..8 {
+            expected[16 * i + j] = 0xF;
+        }
+    }
+    assert_eq!(&output.stdout, &expected);
+    assert_eq!(&output.stderr, b"0+8 records in\n4+0 records out\n");
+}