Merge branch 'uutils:master' into ls_fix_errno_1

src/uu/cksum/src/cksum.rs

@@ -11,8 +11,7 @@ use std::fs::File;
 use std::io::{self, stdin, BufReader, Read};
 use std::path::Path;
 use uucore::display::Quotable;
-use uucore::error::UResult;
+use uucore::error::{FromIo, UResult};
-use uucore::error::USimpleError;
 use uucore::show;
 use uucore::InvalidEncodingHandling;
 
@@ -81,27 +80,18 @@ fn cksum(fname: &str) -> io::Result<(u32, usize)> {
     let mut crc = 0u32;
     let mut size = 0usize;
 
-    let file;
     let mut rd: Box<dyn Read> = match fname {
         "-" => Box::new(stdin()),
         _ => {
-            let path = &Path::new(fname);
+            let p = Path::new(fname);
-            if path.is_dir() {
+
-                return Err(std::io::Error::new(
+            // Directories should not give an error, but should be interpreted
-                    io::ErrorKind::InvalidInput,
+            // as empty files to match GNU semantics.
-                    "Is a directory",
+            if p.is_dir() {
-                ));
+                Box::new(BufReader::new(io::empty())) as Box<dyn Read>
-            };
+            } else {
-            // Silent the warning as we want to the error message
+                Box::new(BufReader::new(File::open(p)?)) as Box<dyn Read>
-            #[allow(clippy::question_mark)]
+            }
-            if path.metadata().is_err() {
-                return Err(std::io::Error::new(
-                    io::ErrorKind::NotFound,
-                    "No such file or directory",
-                ));
-            };
-            file = File::open(&path)?;
-            Box::new(BufReader::new(file))
         }
     };
 
@@ -136,23 +126,16 @@ pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     };
 
     if files.is_empty() {
-        match cksum("-") {
+        let (crc, size) = cksum("-")?;
-            Ok((crc, size)) => println!("{} {}", crc, size),
+        println!("{} {}", crc, size);
-            Err(err) => {
-                return Err(USimpleError::new(2, format!("{}", err)));
-            }
-        }
         return Ok(());
     }
 
     for fname in &files {
-        match cksum(fname.as_ref()) {
+        match cksum(fname.as_ref()).map_err_context(|| format!("{}", fname.maybe_quote())) {
             Ok((crc, size)) => println!("{} {} {}", crc, size, fname),
-            Err(err) => show!(USimpleError::new(
+            Err(err) => show!(err),
-                2,
+        };
-                format!("{}: {}", fname.maybe_quote(), err)
-            )),
-        }
     }
     Ok(())
 }

src/uu/ls/src/ls.rs

@@ -1393,8 +1393,16 @@ fn list(locs: Vec<&Path>, config: Config) -> UResult<()> {
 
     display_items(&files, &config, &mut out);
 
-    for dir in &dirs {
+    for (pos, dir) in dirs.iter().enumerate() {
-        enter_directory(dir, &config, initial_locs_len, &mut out);
+        // Print dir heading - name... 'total' comes after error display
+        if initial_locs_len > 1 || config.recursive {
+            if pos.eq(&0usize) && files.is_empty() {
+                let _ = writeln!(out, "{}:", dir.p_buf.display());
+            } else {
+                let _ = writeln!(out, "\n{}:", dir.p_buf.display());
+            }
+        }
+        enter_directory(dir, &config, &mut out);
     }
 
     Ok(())
@@ -1464,12 +1472,7 @@ fn should_display(entry: &DirEntry, config: &Config) -> bool {
     true
 }
 
-fn enter_directory(
+fn enter_directory(dir: &PathData, config: &Config, out: &mut BufWriter<Stdout>) {
-    dir: &PathData,
-    config: &Config,
-    initial_locs_len: usize,
-    out: &mut BufWriter<Stdout>,
-) {
     // Create vec of entries with initial dot files
     let mut entries: Vec<PathData> = if config.files == Files::All {
         vec![
@@ -1524,10 +1527,6 @@ fn enter_directory(
     sort_entries(&mut vec_path_data, config, out);
     entries.append(&mut vec_path_data);
 
-    // Print dir heading - name...
-    if initial_locs_len > 1 || config.recursive {
-        let _ = writeln!(out, "\n{}:", dir.p_buf.display());
-    }
     // ...and total
     if config.format == Format::Long {
         display_total(&entries, config, out);
@@ -1544,7 +1543,8 @@ fn enter_directory(
             .filter(|p| p.ft.get().unwrap().is_some())
             .filter(|p| p.ft.get().unwrap().unwrap().is_dir())
         {
-            enter_directory(e, config, 0, out);
+            let _ = writeln!(out, "\n{}:", e.p_buf.display());
+            enter_directory(e, config, out);
         }
     }
 }

src/uu/pr/src/pr.rs

@@ -25,6 +25,7 @@ use std::io::{stdin, stdout, BufRead, BufReader, Lines, Read, Write};
 use std::os::unix::fs::FileTypeExt;
 
 use uucore::display::Quotable;
+use uucore::error::UResult;
 
 type IOError = std::io::Error;
 
@@ -174,7 +175,8 @@ pub fn uu_app() -> clap::App<'static, 'static> {
     clap::App::new(uucore::util_name())
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(uucore::InvalidEncodingHandling::Ignore)
         .accept_any();
@@ -388,7 +390,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
 
     if matches.opt_present("version") {
         println!("{} {}", NAME, VERSION);
-        return 0;
+        return Ok(());
     }
 
     let mut files = matches.free.clone();
@@ -412,7 +414,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
             Ok(options) => options,
             Err(err) => {
                 print_error(&matches, err);
-                return 1;
+                return Err(1.into());
             }
         };
 
@@ -430,11 +432,10 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
             _ => 0,
         };
         if status != 0 {
-            return status;
+            return Err(status.into());
         }
     }
-
+    Ok(())
-    0
 }
 
 /// Returns re-written arguments which are passed to the program.
@@ -470,7 +471,7 @@ fn print_error(matches: &Matches, err: PrError) {
     }
 }
 
-fn print_usage(opts: &mut getopts::Options, matches: &Matches) -> i32 {
+fn print_usage(opts: &mut getopts::Options, matches: &Matches) -> UResult<()> {
     println!("{} {} -- print files", NAME, VERSION);
     println!();
     println!(
@@ -508,10 +509,9 @@ fn print_usage(opts: &mut getopts::Options, matches: &Matches) -> i32 {
         options::COLUMN_OPTION
     );
     if matches.free.is_empty() {
-        return 1;
+        return Err(1.into());
     }
-
+    Ok(())
-    0
 }
 
 fn parse_usize(matches: &Matches, opt: &str) -> Option<Result<usize, PrError>> {

src/uu/realpath/src/realpath.rs

@@ -17,6 +17,7 @@ use std::{
 };
 use uucore::{
     display::{print_verbatim, Quotable},
+    error::{FromIo, UResult},
     fs::{canonicalize, MissingHandling, ResolveMode},
 };
 
@@ -36,7 +37,8 @@ fn usage() -> String {
     format!("{0} [OPTION]... FILE...", uucore::execution_phrase())
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let usage = usage();
 
     let matches = uu_app().usage(&usage[..]).get_matches_from(args);
@@ -60,16 +62,16 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     } else {
         MissingHandling::Normal
     };
-    let mut retcode = 0;
     for path in &paths {
-        if let Err(e) = resolve_path(path, strip, zero, logical, can_mode) {
+        let result = resolve_path(path, strip, zero, logical, can_mode);
-            if !quiet {
+        if !quiet {
-                show_error!("{}: {}", path.maybe_quote(), e);
+            show_if_err!(result.map_err_context(|| path.maybe_quote().to_string()));
-            }
+        }
-            retcode = 1
-        };
     }
-    retcode
+    // Although we return `Ok`, it is possible that a call to
+    // `show!()` above has set the exit code for the program to a
+    // non-zero integer.
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {

src/uu/runcon/src/errors.rs

@@ -1,12 +1,22 @@
 use std::ffi::OsString;
-use std::fmt::Write;
+use std::fmt::{Display, Formatter, Write};
 use std::io;
 use std::str::Utf8Error;
 
 use uucore::display::Quotable;
+use uucore::error::UError;
 
 pub(crate) type Result<T> = std::result::Result<T, Error>;
 
+// This list is NOT exhaustive. This command might perform an `execvp()` to run
+// a different program. When that happens successfully, the exit status of this
+// process will be the exit status of that program.
+pub(crate) mod error_exit_status {
+    pub const NOT_FOUND: i32 = 127;
+    pub const COULD_NOT_EXECUTE: i32 = 126;
+    pub const ANOTHER_ERROR: i32 = libc::EXIT_FAILURE;
+}
+
 #[derive(thiserror::Error, Debug)]
 pub(crate) enum Error {
     #[error("No command is specified")]
@@ -63,13 +73,44 @@ impl Error {
     }
 }
 
-pub(crate) fn report_full_error(mut err: &dyn std::error::Error) -> String {
+pub(crate) fn write_full_error<W>(writer: &mut W, err: &dyn std::error::Error) -> std::fmt::Result
-    let mut desc = String::with_capacity(256);
+where
-    write!(&mut desc, "{}", err).unwrap();
+    W: Write,
+{
+    write!(writer, "{}", err)?;
+    let mut err = err;
     while let Some(source) = err.source() {
         err = source;
-        write!(&mut desc, ": {}", err).unwrap();
+        write!(writer, ": {}", err)?;
+    }
+    write!(writer, ".")?;
+    Ok(())
+}
+
+#[derive(Debug)]
+pub(crate) struct RunconError {
+    inner: Error,
+    code: i32,
+}
+
+impl RunconError {
+    pub(crate) fn new(e: Error) -> RunconError {
+        RunconError::with_code(error_exit_status::ANOTHER_ERROR, e)
+    }
+
+    pub(crate) fn with_code(code: i32, e: Error) -> RunconError {
+        RunconError { inner: e, code }
+    }
+}
+
+impl std::error::Error for RunconError {}
+impl UError for RunconError {
+    fn code(&self) -> i32 {
+        self.code
+    }
+}
+impl Display for RunconError {
+    fn fmt(&self, f: &mut Formatter) -> std::fmt::Result {
+        write_full_error(f, &self.inner)
     }
-    desc.push('.');
-    desc
 }

src/uu/runcon/src/runcon.rs

@@ -1,6 +1,6 @@
 // spell-checker:ignore (vars) RFILE
 
-use uucore::{show_error, show_usage_error};
+use uucore::error::{UResult, UUsageError};
 
 use clap::{App, Arg};
 use selinux::{OpaqueSecurityContext, SecurityClass, SecurityContext};
@@ -13,7 +13,8 @@ use std::{io, ptr};
 
 mod errors;
 
-use errors::{report_full_error, Error, Result};
+use errors::error_exit_status;
+use errors::{Error, Result, RunconError};
 
 const VERSION: &str = env!("CARGO_PKG_VERSION");
 const ABOUT: &str = "Run command with specified security context.";
@@ -35,16 +36,6 @@ pub mod options {
     pub const RANGE: &str = "range";
 }
 
-// This list is NOT exhaustive. This command might perform an `execvp()` to run
-// a different program. When that happens successfully, the exit status of this
-// process will be the exit status of that program.
-mod error_exit_status {
-    pub const SUCCESS: i32 = libc::EXIT_SUCCESS;
-    pub const NOT_FOUND: i32 = 127;
-    pub const COULD_NOT_EXECUTE: i32 = 126;
-    pub const ANOTHER_ERROR: i32 = libc::EXIT_FAILURE;
-}
-
 fn get_usage() -> String {
     format!(
         "{0} [CONTEXT COMMAND [ARG...]]\n    \
@@ -53,7 +44,8 @@ fn get_usage() -> String {
     )
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let usage = get_usage();
 
     let config = uu_app().usage(usage.as_ref());
@@ -65,39 +57,28 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 match r.kind {
                     clap::ErrorKind::HelpDisplayed | clap::ErrorKind::VersionDisplayed => {
                         println!("{}", r);
-                        return error_exit_status::SUCCESS;
+                        return Ok(());
                     }
                     _ => {}
                 }
             }
-
+            return Err(UUsageError::new(
-            show_usage_error!("{}.\n", r);
+                error_exit_status::ANOTHER_ERROR,
-            return error_exit_status::ANOTHER_ERROR;
+                format!("{}", r),
+            ));
         }
     };
 
     match &options.mode {
-        CommandLineMode::Print => {
+        CommandLineMode::Print => print_current_context().map_err(|e| RunconError::new(e).into()),
-            if let Err(r) = print_current_context() {
-                show_error!("{}", report_full_error(&r));
-                return error_exit_status::ANOTHER_ERROR;
-            }
-        }
-
         CommandLineMode::PlainContext { context, command } => {
-            let (exit_status, err) =
+            get_plain_context(context)
-                if let Err(err) = get_plain_context(context).and_then(set_next_exec_context) {
+                .and_then(set_next_exec_context)
-                    (error_exit_status::ANOTHER_ERROR, err)
+                .map_err(RunconError::new)?;
-                } else {
+            // On successful execution, the following call never returns,
-                    // On successful execution, the following call never returns,
+            // and this process image is replaced.
-                    // and this process image is replaced.
+            execute_command(command, &options.arguments)
-                    execute_command(command, &options.arguments)
-                };
-
-            show_error!("{}", report_full_error(&err));
-            return exit_status;
         }
-
         CommandLineMode::CustomContext {
             compute_transition_context,
             user,
@@ -106,34 +87,26 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
             range,
             command,
         } => {
-            if let Some(command) = command {
+            match command {
-                let (exit_status, err) = if let Err(err) = get_custom_context(
+                Some(command) => {
-                    *compute_transition_context,
+                    get_custom_context(
-                    user.as_deref(),
+                        *compute_transition_context,
-                    role.as_deref(),
+                        user.as_deref(),
-                    the_type.as_deref(),
+                        role.as_deref(),
-                    range.as_deref(),
+                        the_type.as_deref(),
-                    command,
+                        range.as_deref(),
-                )
+                        command,
-                .and_then(set_next_exec_context)
+                    )
-                {
+                    .and_then(set_next_exec_context)
-                    (error_exit_status::ANOTHER_ERROR, err)
+                    .map_err(RunconError::new)?;
-                } else {
                     // On successful execution, the following call never returns,
                     // and this process image is replaced.
                     execute_command(command, &options.arguments)
-                };
+                }
-
+                None => print_current_context().map_err(|e| RunconError::new(e).into()),
-                show_error!("{}", report_full_error(&err));
-                return exit_status;
-            } else if let Err(r) = print_current_context() {
-                show_error!("{}", report_full_error(&r));
-                return error_exit_status::ANOTHER_ERROR;
             }
         }
     }
-
-    error_exit_status::SUCCESS
 }
 
 pub fn uu_app() -> App<'static, 'static> {
@@ -406,25 +379,19 @@ fn get_custom_context(
     Ok(osc)
 }
 
-/// The actual return type of this function should be `Result<!, (i32, Error)>`
+/// The actual return type of this function should be `UResult<!>`.
 /// However, until the *never* type is stabilized, one way to indicate to the
 /// compiler the only valid return type is to say "if this returns, it will
 /// always return an error".
-fn execute_command(command: &OsStr, arguments: &[OsString]) -> (i32, Error) {
+fn execute_command(command: &OsStr, arguments: &[OsString]) -> UResult<()> {
-    let c_command = match os_str_to_c_string(command) {
+    let c_command = os_str_to_c_string(command).map_err(RunconError::new)?;
-        Ok(v) => v,
-        Err(r) => return (error_exit_status::ANOTHER_ERROR, r),
-    };
 
-    let argv_storage: Vec<CString> = match arguments
+    let argv_storage: Vec<CString> = arguments
         .iter()
         .map(AsRef::as_ref)
         .map(os_str_to_c_string)
         .collect::<Result<_>>()
-    {
+        .map_err(RunconError::new)?;
-        Ok(v) => v,
-        Err(r) => return (error_exit_status::ANOTHER_ERROR, r),
-    };
 
     let mut argv: Vec<*const c_char> = Vec::with_capacity(arguments.len().saturating_add(2));
     argv.push(c_command.as_ptr());
@@ -441,7 +408,7 @@ fn execute_command(command: &OsStr, arguments: &[OsString]) -> (i32, Error) {
     };
 
     let err = Error::from_io1("Executing command", command, err);
-    (exit_status, err)
+    Err(RunconError::with_code(exit_status, err).into())
 }
 
 fn os_str_to_c_string(s: &OsStr) -> Result<CString> {

src/uu/split/src/platform/unix.rs

@@ -2,6 +2,8 @@ use std::env;
 use std::io::Write;
 use std::io::{BufWriter, Result};
 use std::process::{Child, Command, Stdio};
+use uucore::crash;
+
 /// A writer that writes to a shell_process' stdin
 ///
 /// We use a shell process (not directly calling a sub-process) so we can forward the name of the

src/uu/split/src/split.rs

@@ -7,9 +7,6 @@
 
 // spell-checker:ignore (ToDO) PREFIXaa
 
-#[macro_use]
-extern crate uucore;
-
 mod platform;
 
 use clap::{crate_version, App, Arg, ArgMatches};
@@ -20,6 +17,7 @@ use std::io::{stdin, BufRead, BufReader, BufWriter, Read, Write};
 use std::path::Path;
 use std::{char, fs::remove_file};
 use uucore::display::Quotable;
+use uucore::error::{FromIo, UResult, USimpleError, UUsageError};
 use uucore::parse_size::parse_size;
 
 static OPT_BYTES: &str = "bytes";
@@ -53,7 +51,8 @@ size is 1000, and default PREFIX is 'x'. With no INPUT, or when INPUT is
     )
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let usage = usage();
     let long_usage = get_long_usage();
 
@@ -83,15 +82,17 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     settings.additional_suffix = matches.value_of(OPT_ADDITIONAL_SUFFIX).unwrap().to_owned();
 
     settings.verbose = matches.occurrences_of("verbose") > 0;
-    settings.strategy = Strategy::from(&matches);
+    settings.strategy = Strategy::from(&matches)?;
     settings.input = matches.value_of(ARG_INPUT).unwrap().to_owned();
     settings.prefix = matches.value_of(ARG_PREFIX).unwrap().to_owned();
 
     if matches.occurrences_of(OPT_FILTER) > 0 {
         if cfg!(windows) {
             // see https://github.com/rust-lang/rust/issues/29494
-            show_error!("{} is currently not supported in this platform", OPT_FILTER);
+            return Err(USimpleError::new(
-            std::process::exit(-1);
+                -1,
+                format!("{} is currently not supported in this platform", OPT_FILTER),
+            ));
         } else {
             settings.filter = Some(matches.value_of(OPT_FILTER).unwrap().to_owned());
         }
@@ -193,7 +194,7 @@ enum Strategy {
 
 impl Strategy {
     /// Parse a strategy from the command-line arguments.
-    fn from(matches: &ArgMatches) -> Self {
+    fn from(matches: &ArgMatches) -> UResult<Self> {
         // Check that the user is not specifying more than one strategy.
         //
         // Note: right now, this exact behavior cannot be handled by
@@ -204,26 +205,26 @@ impl Strategy {
             matches.occurrences_of(OPT_BYTES),
             matches.occurrences_of(OPT_LINE_BYTES),
         ) {
-            (0, 0, 0) => Strategy::Lines(1000),
+            (0, 0, 0) => Ok(Strategy::Lines(1000)),
             (1, 0, 0) => {
                 let s = matches.value_of(OPT_LINES).unwrap();
-                let n =
+                let n = parse_size(s)
-                    parse_size(s).unwrap_or_else(|e| crash!(1, "invalid number of lines: {}", e));
+                    .map_err(|e| USimpleError::new(1, format!("invalid number of lines: {}", e)))?;
-                Strategy::Lines(n)
+                Ok(Strategy::Lines(n))
             }
             (0, 1, 0) => {
                 let s = matches.value_of(OPT_BYTES).unwrap();
-                let n =
+                let n = parse_size(s)
-                    parse_size(s).unwrap_or_else(|e| crash!(1, "invalid number of bytes: {}", e));
+                    .map_err(|e| USimpleError::new(1, format!("invalid number of bytes: {}", e)))?;
-                Strategy::Bytes(n)
+                Ok(Strategy::Bytes(n))
             }
             (0, 0, 1) => {
                 let s = matches.value_of(OPT_LINE_BYTES).unwrap();
-                let n =
+                let n = parse_size(s)
-                    parse_size(s).unwrap_or_else(|e| crash!(1, "invalid number of bytes: {}", e));
+                    .map_err(|e| USimpleError::new(1, format!("invalid number of bytes: {}", e)))?;
-                Strategy::LineBytes(n)
+                Ok(Strategy::LineBytes(n))
             }
-            _ => crash!(1, "cannot split in more than one way"),
+            _ => Err(UUsageError::new(1, "cannot split in more than one way")),
         }
     }
 }
@@ -249,7 +250,7 @@ trait Splitter {
         &mut self,
         reader: &mut BufReader<Box<dyn Read>>,
         writer: &mut BufWriter<Box<dyn Write>>,
-    ) -> u128;
+    ) -> std::io::Result<u128>;
 }
 
 struct LineSplitter {
@@ -269,21 +270,17 @@ impl Splitter for LineSplitter {
         &mut self,
         reader: &mut BufReader<Box<dyn Read>>,
         writer: &mut BufWriter<Box<dyn Write>>,
-    ) -> u128 {
+    ) -> std::io::Result<u128> {
         let mut bytes_consumed = 0u128;
         let mut buffer = String::with_capacity(1024);
         for _ in 0..self.lines_per_split {
-            let bytes_read = reader
+            let bytes_read = reader.read_line(&mut buffer)?;
-                .read_line(&mut buffer)
-                .unwrap_or_else(|_| crash!(1, "error reading bytes from input file"));
             // If we ever read 0 bytes then we know we've hit EOF.
             if bytes_read == 0 {
-                return bytes_consumed;
+                return Ok(bytes_consumed);
             }
 
-            writer
+            writer.write_all(buffer.as_bytes())?;
-                .write_all(buffer.as_bytes())
-                .unwrap_or_else(|_| crash!(1, "error writing bytes to output file"));
             // Empty out the String buffer since `read_line` appends instead of
             // replaces.
             buffer.clear();
@@ -291,7 +288,7 @@ impl Splitter for LineSplitter {
             bytes_consumed += bytes_read as u128;
         }
 
-        bytes_consumed
+        Ok(bytes_consumed)
     }
 }
 
@@ -312,7 +309,7 @@ impl Splitter for ByteSplitter {
         &mut self,
         reader: &mut BufReader<Box<dyn Read>>,
         writer: &mut BufWriter<Box<dyn Write>>,
-    ) -> u128 {
+    ) -> std::io::Result<u128> {
         // We buffer reads and writes. We proceed until `bytes_consumed` is
         // equal to `self.bytes_per_split` or we reach EOF.
         let mut bytes_consumed = 0u128;
@@ -329,22 +326,18 @@ impl Splitter for ByteSplitter {
                 // than BUFFER_SIZE in this branch.
                 (self.bytes_per_split - bytes_consumed) as usize
             };
-            let bytes_read = reader
+            let bytes_read = reader.read(&mut buffer[0..bytes_desired])?;
-                .read(&mut buffer[0..bytes_desired])
-                .unwrap_or_else(|_| crash!(1, "error reading bytes from input file"));
             // If we ever read 0 bytes then we know we've hit EOF.
             if bytes_read == 0 {
-                return bytes_consumed;
+                return Ok(bytes_consumed);
             }
 
-            writer
+            writer.write_all(&buffer[0..bytes_read])?;
-                .write_all(&buffer[0..bytes_read])
-                .unwrap_or_else(|_| crash!(1, "error writing bytes to output file"));
 
             bytes_consumed += bytes_read as u128;
         }
 
-        bytes_consumed
+        Ok(bytes_consumed)
     }
 }
 
@@ -380,17 +373,16 @@ fn num_prefix(i: usize, width: usize) -> String {
     c
 }
 
-fn split(settings: &Settings) -> i32 {
+fn split(settings: &Settings) -> UResult<()> {
     let mut reader = BufReader::new(if settings.input == "-" {
         Box::new(stdin()) as Box<dyn Read>
     } else {
-        let r = File::open(Path::new(&settings.input)).unwrap_or_else(|_| {
+        let r = File::open(Path::new(&settings.input)).map_err_context(|| {
-            crash!(
+            format!(
-                1,
                 "cannot open {} for reading: No such file or directory",
                 settings.input.quote()
             )
-        });
+        })?;
         Box::new(r) as Box<dyn Read>
     });
 
@@ -416,10 +408,12 @@ fn split(settings: &Settings) -> i32 {
         filename.push_str(settings.additional_suffix.as_ref());
         let mut writer = platform::instantiate_current_writer(&settings.filter, filename.as_str());
 
-        let bytes_consumed = splitter.consume(&mut reader, &mut writer);
+        let bytes_consumed = splitter
+            .consume(&mut reader, &mut writer)
+            .map_err_context(|| "input/output error".to_string())?;
         writer
             .flush()
-            .unwrap_or_else(|e| crash!(1, "error flushing to output file: {}", e));
+            .map_err_context(|| "error flushing to output file".to_string())?;
 
         // If we didn't write anything we should clean up the empty file, and
         // break from the loop.
@@ -428,12 +422,12 @@ fn split(settings: &Settings) -> i32 {
             // Complicated, I know...
             if settings.filter.is_none() {
                 remove_file(filename)
-                    .unwrap_or_else(|e| crash!(1, "error removing empty file: {}", e));
+                    .map_err_context(|| "error removing empty file".to_string())?;
             }
             break;
         }
 
         fileno += 1;
     }
-    0
+    Ok(())
 }

src/uu/timeout/src/timeout.rs

@@ -17,6 +17,7 @@ use std::io::ErrorKind;
 use std::process::{Command, Stdio};
 use std::time::Duration;
 use uucore::display::Quotable;
+use uucore::error::{UResult, USimpleError};
 use uucore::process::ChildExt;
 use uucore::signals::{signal_by_name_or_value, signal_name_by_value};
 use uucore::InvalidEncodingHandling;
@@ -99,7 +100,8 @@ impl Config {
     }
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(InvalidEncodingHandling::ConvertLossy)
         .accept_any();
@@ -188,32 +190,36 @@ fn timeout(
     foreground: bool,
     preserve_status: bool,
     verbose: bool,
-) -> i32 {
+) -> UResult<()> {
     if !foreground {
         unsafe { libc::setpgid(0, 0) };
     }
-    let mut process = match Command::new(&cmd[0])
+    let mut process = Command::new(&cmd[0])
         .args(&cmd[1..])
         .stdin(Stdio::inherit())
         .stdout(Stdio::inherit())
         .stderr(Stdio::inherit())
         .spawn()
-    {
+        .map_err(|err| {
-        Ok(p) => p,
+            let status_code = if err.kind() == ErrorKind::NotFound {
-        Err(err) => {
-            show_error!("failed to execute process: {}", err);
-            if err.kind() == ErrorKind::NotFound {
                 // FIXME: not sure which to use
-                return 127;
+                127
             } else {
                 // FIXME: this may not be 100% correct...
-                return 126;
+                126
-            }
+            };
-        }
+            USimpleError::new(status_code, format!("failed to execute process: {}", err))
-    };
+        })?;
     unblock_sigchld();
     match process.wait_or_timeout(duration) {
-        Ok(Some(status)) => status.code().unwrap_or_else(|| status.signal().unwrap()),
+        Ok(Some(status)) => {
+            let status_code = status.code().unwrap_or_else(|| status.signal().unwrap());
+            if status_code == 0 {
+                Ok(())
+            } else {
+                Err(status_code.into())
+            }
+        }
         Ok(None) => {
             if verbose {
                 show_error!(
@@ -222,38 +228,50 @@ fn timeout(
                     cmd[0].quote()
                 );
             }
-            crash_if_err!(ERR_EXIT_STATUS, process.send_signal(signal));
+            process
+                .send_signal(signal)
+                .map_err(|e| USimpleError::new(ERR_EXIT_STATUS, format!("{}", e)))?;
             if let Some(kill_after) = kill_after {
                 match process.wait_or_timeout(kill_after) {
                     Ok(Some(status)) => {
                         if preserve_status {
-                            status.code().unwrap_or_else(|| status.signal().unwrap())
+                            let status_code =
+                                status.code().unwrap_or_else(|| status.signal().unwrap());
+                            if status_code == 0 {
+                                Ok(())
+                            } else {
+                                Err(status_code.into())
+                            }
                         } else {
-                            124
+                            Err(124.into())
                         }
                     }
                     Ok(None) => {
                         if verbose {
                             show_error!("sending signal KILL to command {}", cmd[0].quote());
                         }
-                        crash_if_err!(
+                        process
-                            ERR_EXIT_STATUS,
+                            .send_signal(uucore::signals::signal_by_name_or_value("KILL").unwrap())
-                            process.send_signal(
+                            .map_err(|e| USimpleError::new(ERR_EXIT_STATUS, format!("{}", e)))?;
-                                uucore::signals::signal_by_name_or_value("KILL").unwrap()
+                        process
-                            )
+                            .wait()
-                        );
+                            .map_err(|e| USimpleError::new(ERR_EXIT_STATUS, format!("{}", e)))?;
-                        crash_if_err!(ERR_EXIT_STATUS, process.wait());
+                        Err(137.into())
-                        137
                     }
-                    Err(_) => 124,
+                    Err(_) => Err(124.into()),
                 }
             } else {
-                124
+                Err(124.into())
             }
         }
         Err(_) => {
-            crash_if_err!(ERR_EXIT_STATUS, process.send_signal(signal));
+            // We're going to return ERR_EXIT_STATUS regardless of
-            ERR_EXIT_STATUS
+            // whether `send_signal()` succeeds or fails, so just
+            // ignore the return value.
+            process
+                .send_signal(signal)
+                .map_err(|e| USimpleError::new(ERR_EXIT_STATUS, format!("{}", e)))?;
+            Err(ERR_EXIT_STATUS.into())
         }
     }
 }

src/uu/tsort/src/tsort.rs

@@ -5,16 +5,13 @@
 //  *
 //  * For the full copyright and license information, please view the LICENSE
 //  * file that was distributed with this source code.
-
-#[macro_use]
-extern crate uucore;
-
 use clap::{crate_version, App, Arg};
 use std::collections::{HashMap, HashSet};
 use std::fs::File;
 use std::io::{stdin, BufRead, BufReader, Read};
 use std::path::Path;
 use uucore::display::Quotable;
+use uucore::error::{FromIo, UResult, USimpleError};
 use uucore::InvalidEncodingHandling;
 
 static SUMMARY: &str = "Topological sort the strings in FILE.
@@ -26,7 +23,8 @@ mod options {
     pub const FILE: &str = "file";
 }
 
-pub fn uumain(args: impl uucore::Args) -> i32 {
+#[uucore_procs::gen_uumain]
+pub fn uumain(args: impl uucore::Args) -> UResult<()> {
     let args = args
         .collect_str(InvalidEncodingHandling::ConvertLossy)
         .accept_any();
@@ -43,13 +41,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         stdin_buf = stdin();
         &mut stdin_buf as &mut dyn Read
     } else {
-        file_buf = match File::open(Path::new(&input)) {
+        file_buf = File::open(Path::new(&input)).map_err_context(|| input.to_string())?;
-            Ok(a) => a,
-            _ => {
-                show_error!("{}: No such file or directory", input.maybe_quote());
-                return 1;
-            }
-        };
         &mut file_buf as &mut dyn Read
     });
 
@@ -69,11 +61,15 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 for ab in tokens.chunks(2) {
                     match ab.len() {
                         2 => g.add_edge(&ab[0], &ab[1]),
-                        _ => crash!(
+                        _ => {
-                            1,
+                            return Err(USimpleError::new(
-                            "{}: input contains an odd number of tokens",
+                                1,
-                            input.maybe_quote()
+                                format!(
-                        ),
+                                    "{}: input contains an odd number of tokens",
+                                    input.maybe_quote()
+                                ),
+                            ))
+                        }
                     }
                 }
             }
@@ -84,14 +80,17 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     g.run_tsort();
 
     if !g.is_acyclic() {
-        crash!(1, "{}, input contains a loop:", input);
+        return Err(USimpleError::new(
+            1,
+            format!("{}, input contains a loop:", input),
+        ));
     }
 
     for x in &g.result {
         println!("{}", x);
     }
 
-    0
+    Ok(())
 }
 
 pub fn uu_app() -> App<'static, 'static> {

src/uucore/src/lib/mods/error.rs

@@ -371,7 +371,7 @@ impl UError for UUsageError {
 /// ```
 #[derive(Debug)]
 pub struct UIoError {
-    context: String,
+    context: Option<String>,
     inner: std::io::Error,
 }
 
@@ -379,7 +379,7 @@ impl UIoError {
     #[allow(clippy::new_ret_no_self)]
     pub fn new<S: Into<String>>(kind: std::io::ErrorKind, context: S) -> Box<dyn UError> {
         Box::new(Self {
-            context: context.into(),
+            context: Some(context.into()),
             inner: kind.into(),
         })
     }
@@ -435,7 +435,11 @@ impl Display for UIoError {
             capitalize(&mut message);
             &message
         };
-        write!(f, "{}: {}", self.context, message)
+        if let Some(ctx) = &self.context {
+            write!(f, "{}: {}", ctx, message)
+        } else {
+            write!(f, "{}", message)
+        }
     }
 }
 
@@ -464,7 +468,7 @@ pub trait FromIo<T> {
 impl FromIo<Box<UIoError>> for std::io::Error {
     fn map_err_context(self, context: impl FnOnce() -> String) -> Box<UIoError> {
         Box::new(UIoError {
-            context: (context)(),
+            context: Some((context)()),
             inner: self,
         })
     }
@@ -479,12 +483,28 @@ impl<T> FromIo<UResult<T>> for std::io::Result<T> {
 impl FromIo<Box<UIoError>> for std::io::ErrorKind {
     fn map_err_context(self, context: impl FnOnce() -> String) -> Box<UIoError> {
         Box::new(UIoError {
-            context: (context)(),
+            context: Some((context)()),
             inner: std::io::Error::new(self, ""),
         })
     }
 }
 
+impl From<std::io::Error> for UIoError {
+    fn from(f: std::io::Error) -> UIoError {
+        UIoError {
+            context: None,
+            inner: f,
+        }
+    }
+}
+
+impl From<std::io::Error> for Box<dyn UError> {
+    fn from(f: std::io::Error) -> Box<dyn UError> {
+        let u_error: UIoError = f.into();
+        Box::new(u_error) as Box<dyn UError>
+    }
+}
+
 /// Shorthand to construct [`UIoError`]-instances.
 ///
 /// This macro serves as a convenience call to quickly construct instances of

tests/by-util/test_cksum.rs

@@ -74,9 +74,8 @@ fn test_invalid_file() {
     at.mkdir(folder_name);
     ts.ucmd()
         .arg(folder_name)
-        .fails()
+        .succeeds()
-        .no_stdout()
+        .stdout_only("4294967295 0 asdf\n");
-        .stderr_contains("cksum: asdf: Is a directory");
 }
 
 // Make sure crc is correct for files larger than 32 bytes

tests/by-util/test_ls.rs

@@ -107,6 +107,28 @@ fn test_ls_io_errors() {
         .stdout_contains("some-dir4");
 }
 
+#[test]
+fn test_ls_only_dirs_formatting() {
+    let scene = TestScenario::new(util_name!());
+    let at = &scene.fixtures;
+    at.mkdir("some-dir1");
+    at.mkdir("some-dir2");
+    at.mkdir("some-dir3");
+
+    #[cfg(unix)]
+    {
+        scene.ucmd().arg("-1").arg("-R").succeeds().stdout_only(
+            ".:\nsome-dir1\nsome-dir2\nsome-dir3\n\n./some-dir1:\n\n./some-dir2:\n\n./some-dir3:\n",
+        );
+    }
+    #[cfg(windows)]
+    {
+        scene.ucmd().arg("-1").arg("-R").succeeds().stdout_only(
+            ".:\nsome-dir1\nsome-dir2\nsome-dir3\n\n.\\some-dir1:\n\n.\\some-dir2:\n\n.\\some-dir3:\n",
+        );
+    }
+}
+
 #[test]
 fn test_ls_walk_glob() {
     let scene = TestScenario::new(util_name!());