add util: tabs

README.md

@@ -151,7 +151,7 @@ https://github.com/jgarzik/posixutils
  - [ ] strings
  - [ ] strip (Development)
  - [x] stty
- - [ ] tabs
+ - [x] tabs
  - [ ] tail
  - [ ] talk
  - [x] tee

TODO.md

@@ -3,6 +3,7 @@
 ## Translations
 
 * Standard OS error texts must be translated
+* Clap error messages must be translated
 
 ## OS errors
 

file/src/cat.rs

@@ -70,12 +70,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut exit_code = 0;
 
     for filename in &args.files {
-        match cat_file(filename) {
-            Ok(()) => {}
-            Err(e) => {
-                exit_code = 1;
-                eprintln!("{}: {}", filename, e);
-            }
+        if let Err(e) = cat_file(filename) {
+            exit_code = 1;
+            eprintln!("{}: {}", filename, e);
         }
     }
 

plib/src/lib.rs

@@ -16,6 +16,9 @@ pub const PROJECT_NAME: &'static str = "posixutils-rs";
 
 pub const BUFSZ: usize = 8 * 1024;
 
+pub const TERM_VAR: &'static str = "TERM";
+pub const DEFAULT_TERM: &'static str = "vt100";
+
 pub struct TestPlan {
     pub cmd: String,
     pub args: Vec<String>,
@@ -50,3 +53,16 @@ pub fn run_test(plan: TestPlan) {
     assert!(output.status.success());
     assert_eq!(output.status.code(), Some(0));
 }
+
+pub fn get_terminal() -> String {
+    let term: String = match std::env::var(TERM_VAR) {
+        Ok(val) => val,
+        Err(_) => String::new(),
+    };
+
+    if term.is_empty() {
+        String::from(DEFAULT_TERM)
+    } else {
+        term
+    }
+}

screen/Cargo.toml

@@ -18,6 +18,10 @@ libc = "0.2"
 name = "stty"
 path = "src/stty.rs"
 
+[[bin]]
+name = "tabs"
+path = "src/tabs.rs"
+
 [[bin]]
 name = "tput"
 path = "src/tput.rs"

screen/src/tabs.rs

@@ -0,0 +1,229 @@
+//
+// Copyright (c) 2024 Jeff Garzik
+//
+// This file is part of the posixutils-rs project covered under
+// the MIT License.  For the full license text, please see the LICENSE
+// file in the root directory of this project.
+// SPDX-License-Identifier: MIT
+//
+// TODO:
+// - (efficiency): collect all output in a buffer, then write to stdout
+// - Research if 100 is a POSIX-compliant limit for MAX_STOPS
+//
+
+extern crate clap;
+extern crate plib;
+
+use clap::Parser;
+use gettextrs::{bind_textdomain_codeset, gettext, textdomain};
+use plib::PROJECT_NAME;
+use std::io::{self, Error, ErrorKind, Write};
+use terminfo::{capability as cap, Database};
+
+// arbitrarily chosen.  todo: search if POSIX-ly correct.
+const MAX_STOPS: usize = 100;
+
+/// tabs - set terminal tabs
+#[derive(Parser, Debug)]
+#[command(author, version, about, long_about)]
+struct Args {
+    /// Indicate the type of terminal.
+    #[arg(short = 'T', long)]
+    term: Option<String>,
+
+    /// Specify repetitive tab stops separated by (1) columns
+    #[arg(short = '1', long)]
+    rep_1: bool,
+
+    /// Specify repetitive tab stops separated by (2) columns
+    #[arg(short = '2', long)]
+    rep_2: bool,
+
+    /// Specify repetitive tab stops separated by (3) columns
+    #[arg(short = '3', long)]
+    rep_3: bool,
+
+    /// Specify repetitive tab stops separated by (4) columns
+    #[arg(short = '4', long)]
+    rep_4: bool,
+
+    /// Specify repetitive tab stops separated by (5) columns
+    #[arg(short = '5', long)]
+    rep_5: bool,
+
+    /// Specify repetitive tab stops separated by (6) columns
+    #[arg(short = '6', long)]
+    rep_6: bool,
+
+    /// Specify repetitive tab stops separated by (7) columns
+    #[arg(short = '7', long)]
+    rep_7: bool,
+
+    /// Specify repetitive tab stops separated by (8) columns
+    #[arg(short = '8', long)]
+    rep_8: bool,
+
+    /// Specify repetitive tab stops separated by (9) columns
+    #[arg(short = '9', long)]
+    rep_9: bool,
+
+    /// Assembler, applicable to some mainframes.
+    /// 1=[1,10,16,36,72]
+    /// 2=[1,10,16,40,72]
+    #[arg(short, long, default_missing_value="1", value_parser = clap::value_parser!(u8).range(1..=2))]
+    assembler: Option<u8>,
+
+    /// COBOL, normal and compact formats.
+    /// 1=[1,8,12,16,20,55]
+    /// 2=[1,6,10,14,49]
+    /// 3=[1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67]
+    #[arg(short, long, default_missing_value="1", value_parser = clap::value_parser!(u8).range(1..=3))]
+    cobol: Option<u8>,
+
+    /// FORTAN: [1,7,11,15,19,23]
+    #[arg(short, long)]
+    fortran: bool,
+
+    /// SNOBOL: [1,10,55]
+    #[arg(short, long)]
+    snobol: bool,
+
+    /// Assembler, applicable to some mainframes. [1,12,20,44]
+    #[arg(short = 'u')]
+    assembler_u: bool,
+
+    /// PL/1: [1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61]
+    #[arg(short, long)]
+    pl1: bool,
+
+    /// Optional: A single command line argument that consists of one or more tab-stop values (n) separated by a separator character
+    tabstops: Option<String>,
+}
+
+fn parse_cmd_line(args: &Args) -> Result<Vec<u16>, &'static str> {
+    let mut tabstops: Vec<u16> = Vec::new();
+    let mut repeating_stop: Option<u16> = None;
+
+    if args.rep_9 {
+        repeating_stop = Some(9);
+    } else if args.rep_8 {
+        repeating_stop = Some(8);
+    } else if args.rep_7 {
+        repeating_stop = Some(7);
+    } else if args.rep_6 {
+        repeating_stop = Some(6);
+    } else if args.rep_5 {
+        repeating_stop = Some(5);
+    } else if args.rep_4 {
+        repeating_stop = Some(4);
+    } else if args.rep_3 {
+        repeating_stop = Some(3);
+    } else if args.rep_2 {
+        repeating_stop = Some(2);
+    } else if args.rep_1 {
+        repeating_stop = Some(1);
+    } else if let Some(variant) = args.assembler {
+        match variant {
+            1 => tabstops = vec![1, 10, 16, 36, 72],
+            2 => tabstops = vec![1, 10, 16, 40, 72],
+            _ => unreachable!(),
+        }
+    } else if let Some(variant) = args.cobol {
+        match variant {
+            1 => tabstops = vec![1, 8, 12, 16, 20, 55],
+            2 => tabstops = vec![1, 6, 10, 14, 49],
+            3 => {
+                tabstops = vec![
+                    1, 6, 10, 14, 18, 22, 26, 30, 34, 38, 42, 46, 50, 54, 58, 62, 67,
+                ]
+            }
+            _ => unreachable!(),
+        }
+    } else if args.fortran {
+        tabstops = vec![1, 7, 11, 15, 19, 23];
+    } else if args.pl1 {
+        tabstops = vec![1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61];
+    } else if args.snobol {
+        tabstops = vec![1, 10, 55];
+    } else if args.assembler_u {
+        tabstops = vec![1, 12, 20, 44];
+    } else if let Some(ref tabstops_str) = args.tabstops {
+        for stop in tabstops_str.split(',') {
+            tabstops.push(
+                stop.parse()
+                    .expect(gettext("Invalid tabstop value.").as_str()),
+            );
+        }
+    }
+
+    // handle repetitive tab stops
+    if let Some(stop_n) = repeating_stop {
+        for _i in 0..MAX_STOPS {
+            tabstops.push(stop_n);
+        }
+    }
+
+    // validate that stops are in strictly ascending order
+    for i in 1..tabstops.len() {
+        if tabstops[i] <= tabstops[i - 1] {
+            return Err("Tabstops must be in strictly ascending order.");
+        }
+    }
+
+    Ok(tabstops)
+}
+
+// set hardware tabs.
+fn set_hw_tabs(info: &Database, tabstops: &Vec<u16>) -> io::Result<()> {
+    let clear_cap = info.get::<cap::ClearAllTabs>();
+    let set_cap = info.get::<cap::SetTab>();
+
+    if clear_cap.is_none() || set_cap.is_none() {
+        let msg = gettext("Terminal does not support hardware tabs.");
+        return Err(Error::new(ErrorKind::Other, msg));
+    }
+    let clear_cap = clear_cap.unwrap();
+    let set_cap = set_cap.unwrap();
+
+    // clear existing tabs
+    if let Err(e) = clear_cap.expand().to(io::stdout()) {
+        let msg = format!("{}: {}", gettext("Failed to clear tabs"), e);
+        return Err(Error::new(ErrorKind::Other, msg));
+    }
+
+    // set new tabs
+    let mut col = 0;
+    for stop in tabstops {
+        let stop = *stop as usize;
+
+        while col < stop {
+            io::stdout().write_all(b" ")?;
+            col += 1;
+        }
+
+        if let Err(e) = set_cap.expand().to(io::stdout()) {
+            let msg = format!("{}: {}", gettext("Failed to set tab"), e);
+            return Err(Error::new(ErrorKind::Other, msg));
+        }
+    }
+
+    Ok(())
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    // parse command line arguments
+    let args = Args::parse();
+
+    textdomain(PROJECT_NAME)?;
+    bind_textdomain_codeset(PROJECT_NAME, "UTF-8")?;
+
+    let info = match args.term {
+        None => Database::from_env().unwrap(),
+        Some(ref termtype) => Database::from_name(termtype).unwrap(),
+    };
+
+    let tabstops = parse_cmd_line(&args)?;
+    set_hw_tabs(&info, &tabstops)?;
+
+    Ok(())
+}

sys/src/ipcrm.rs

@@ -189,12 +189,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let mut exit_code = 0;
 
-    match remove_ipcs(&args) {
-        Ok(()) => {}
-        Err(e) => {
-            exit_code = 1;
-            eprintln!("{}", e);
-        }
+    if let Err(e) = remove_ipcs(&args) {
+        exit_code = 1;
+        eprintln!("{}", e);
     }
 
     std::process::exit(exit_code)

text/src/asa.rs

@@ -85,12 +85,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut exit_code = 0;
 
     for filename in &args.files {
-        match asa_file(filename) {
-            Ok(()) => {}
-            Err(e) => {
-                exit_code = 1;
-                eprintln!("{}: {}", filename, e);
-            }
+        if let Err(e) = asa_file(filename) {
+            exit_code = 1;
+            eprintln!("{}: {}", filename, e);
         }
     }
 

text/src/comm.rs

@@ -169,12 +169,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
 
     let mut exit_code = 0;
 
-    match comm_file(mask, lead_dup, &args.file1, &args.file2) {
-        Ok(()) => {}
-        Err(e) => {
-            exit_code = 1;
-            eprintln!("{}", e);
-        }
+    if let Err(e) = comm_file(mask, lead_dup, &args.file1, &args.file2) {
+        exit_code = 1;
+        eprintln!("{}", e);
     }
 
     std::process::exit(exit_code)

text/src/expand.rs

@@ -166,12 +166,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut exit_code = 0;
 
     for filename in &args.files {
-        match expand_file(&tablist, filename) {
-            Ok(()) => {}
-            Err(e) => {
-                exit_code = 1;
-                eprintln!("{}: {}", filename, e);
-            }
+        if let Err(e) = expand_file(&tablist, filename) {
+            exit_code = 1;
+            eprintln!("{}: {}", filename, e);
         }
     }
 

text/src/fold.rs

@@ -191,12 +191,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut exit_code = 0;
 
     for filename in &args.files {
-        match fold_file(&args, filename) {
-            Ok(()) => {}
-            Err(e) => {
-                exit_code = 1;
-                eprintln!("{}: {}", filename, e);
-            }
+        if let Err(e) = fold_file(&args, filename) {
+            exit_code = 1;
+            eprintln!("{}: {}", filename, e);
         }
     }
 

text/src/head.rs

@@ -105,12 +105,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut first = true;
 
     for filename in &args.files {
-        match head_file(&args, filename, first, want_header) {
-            Ok(()) => {}
-            Err(e) => {
-                exit_code = 1;
-                eprintln!("{}: {}", filename, e);
-            }
+        if let Err(e) = head_file(&args, filename, first, want_header) {
+            exit_code = 1;
+            eprintln!("{}: {}", filename, e);
         }
 
         first = false;