chcon: report verbose write failures without panicking

src/uu/chcon/locales/en-US.ftl

@@ -27,6 +27,7 @@ chcon-error-no-files-specified = No files are specified
 chcon-error-data-out-of-range = Data is out of range
 chcon-error-operation-failed = { $operation } failed
 chcon-error-operation-failed-on = { $operation } failed on { $operand }
+chcon-error-write = write error: { $error }
 
 # Error messages - argument validation
 chcon-error-invalid-context = Invalid security context '{ $context }'.

src/uu/chcon/src/chcon.rs

@@ -23,6 +23,7 @@ use core::ffi::CStr;
 use std::borrow::Cow;
 use std::collections::HashSet;
 use std::ffi::{CString, OsStr, OsString};
+use std::io::Write;
 use std::os::fd::{AsFd, AsRawFd, BorrowedFd, OwnedFd};
 use std::path::{Path, PathBuf};
 use std::{fs, io};
@@ -519,6 +520,7 @@ fn relabel_all(
         // Directories reached on the way down, so a symlink loop is noticed
         // instead of followed forever.
         open_ancestors: HashSet::new(),
+        write_error: None,
         errors,
     };
 
@@ -527,6 +529,10 @@ fn relabel_all(
         walk.visit(&start, operand.as_os_str(), operand, behavior, true);
     }
 
+    if let Some(err) = walk.write_error {
+        walk.errors.push(Error::Write(err));
+    }
+
     walk.errors
 }
 
@@ -537,6 +543,7 @@ struct Walk<'a> {
     context: &'a SELinuxSecurityContext<'a>,
     root_id: Option<DeviceAndINode>,
     open_ancestors: HashSet<DeviceAndINode>,
+    write_error: Option<io::Error>,
     errors: Vec<Error>,
 }
 
@@ -645,11 +652,13 @@ impl Walk<'_> {
     }
 
     fn relabel(&mut self, parent: &DirFd, name: &OsStr, display: &Path) {
-        if self.options.verbose {
-            println!(
+        if self.options.verbose && self.write_error.is_none() {
+            self.write_error = writeln!(
+                io::stdout(),
                 "{}",
                 translate!("chcon-verbose-changing-context", "util_name" => "chcon", "file" => display.quote())
-            );
+            )
+            .err();
         }
 
         if let Err(err) = apply_context(

src/uu/chcon/src/errors.rs

@@ -10,6 +10,7 @@ use std::fmt::Write;
 use std::io;
 
 use uucore::display::Quotable;
+use uucore::error::strip_errno;
 use uucore::translate;
 
 pub(crate) type Result<T> = std::result::Result<T, Error>;
@@ -31,6 +32,9 @@ pub(crate) enum Error {
     #[error(transparent)]
     CommandLine(#[from] clap::Error),
 
+    #[error("{}", translate!("chcon-error-write", "error" => strip_errno(.0)))]
+    Write(io::Error),
+
     #[error("{}", translate!("chcon-error-operation-failed", "operation" => operation))]
     SELinux {
         operation: String,

tests/by-util/test_chcon.rs

@@ -53,6 +53,28 @@ fn recursive_errors() {
     }
 }
 
+#[test]
+#[cfg(target_os = "linux")]
+fn verbose_write_error() {
+    let (at, mut cmd) = at_and_ucmd!();
+    at.touch("a");
+    at.touch("b");
+    let dev_full = std::fs::OpenOptions::new()
+        .write(true)
+        .open("/dev/full")
+        .unwrap();
+
+    let result = cmd
+        .args(&["--verbose", "--type=etc_t", "a", "b", "missing"])
+        .set_stdout(dev_full)
+        .fails_with_code(1);
+    result
+        .stderr_contains("write error: No space left on device")
+        .stderr_contains("Accessing failed on 'missing'");
+
+    assert_eq!(result.stderr_str().matches("write error:").count(), 1);
+}
+
 #[test]
 fn valid_context() {
     let (dir, mut cmd) = at_and_ucmd!();