Implement -a and -t for terminal width setting

Cargo.lock

@@ -75,27 +75,33 @@ dependencies = [
 ]
 
 [[package]]
-name = "clap"
+name = "cc"
-version = "3.1.18"
+version = "1.0.73"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d2dbdf4bdacb33466e854ce889eee8dfd5729abf7ccd7664d0a2d60cd384440b"
+checksum = "2fff2a6927b3bb87f9595d67196a70493f627687a71d87a0d692242c33f58c11"
+
+[[package]]
+name = "clap"
+version = "3.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d646c7ade5eb07c4aa20e907a922750df0c448892513714fd3e4acbc7130829f"
 dependencies = [
  "atty",
  "bitflags",
  "clap_lex",
  "indexmap",
- "lazy_static",
+ "once_cell",
  "strsim",
  "termcolor",
- "terminal_size",
+ "terminal_size 0.1.17",
  "textwrap",
 ]
 
 [[package]]
 name = "clap_lex"
-version = "0.2.0"
+version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a37c35f1112dad5e6e0b1adaff798507497a18fceeb30cceb3bae7d1427b9213"
+checksum = "2850f2f5a82cbf437dd5af4d49848fbdfc27c157c3d010345776f952765261c5"
 dependencies = [
  "os_str_bytes",
 ]
@@ -138,6 +144,27 @@ version = "1.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
 
+[[package]]
+name = "errno"
+version = "0.2.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f639046355ee4f37944e44f60642c6f3a7efa3cf6b78c78a0d989a8ce6c396a1"
+dependencies = [
+ "errno-dragonfly",
+ "libc",
+ "winapi",
+]
+
+[[package]]
+name = "errno-dragonfly"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aa68f1b12764fab894d2755d2518754e71b4fd80ecfb822714a1206c2aab39bf"
+dependencies = [
+ "cc",
+ "libc",
+]
+
 [[package]]
 name = "float-cmp"
 version = "0.9.0"
@@ -174,6 +201,7 @@ dependencies = [
  "const_format",
  "libc",
  "predicates",
+ "terminal_size 0.2.1",
  "thiserror",
 ]
 
@@ -187,6 +215,12 @@ dependencies = [
  "hashbrown",
 ]
 
+[[package]]
+name = "io-lifetimes"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24c3f4eff5495aee4c0399d7b6a0dc2b6e81be84242ffbfcf253ebacccc1d0cb"
+
 [[package]]
 name = "itertools"
 version = "0.10.3"
@@ -208,6 +242,12 @@ version = "0.2.126"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "349d5a591cd28b49e1d1037471617a32ddcda5731b99419008085f72d5a53836"
 
+[[package]]
+name = "linux-raw-sys"
+version = "0.0.46"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4d2456c373231a208ad294c33dc5bff30051eafd954cd4caae83a712b12854d"
+
 [[package]]
 name = "memchr"
 version = "2.5.0"
@@ -229,6 +269,12 @@ dependencies = [
  "autocfg",
 ]
 
+[[package]]
+name = "once_cell"
+version = "1.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18a6dbe30758c9f83eb00cbea4ac95966305f5a7772f3f42ebfc7fc7eddbd8e1"
+
 [[package]]
 name = "os_str_bytes"
 version = "6.0.1"
@@ -306,6 +352,20 @@ version = "0.6.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "49b3de9ec5dc0a3417da371aab17d729997c15010e7fd24ff707773a33bddb64"
 
+[[package]]
+name = "rustix"
+version = "0.35.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d51cc38aa10f6bbb377ed28197aa052aa4e2b762c22be9d3153d01822587e787"
+dependencies = [
+ "bitflags",
+ "errno",
+ "io-lifetimes",
+ "libc",
+ "linux-raw-sys",
+ "windows-sys",
+]
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
@@ -342,6 +402,16 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "terminal_size"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8440c860cf79def6164e4a0a983bcc2305d82419177a0e0c71930d049e3ac5a1"
+dependencies = [
+ "rustix",
+ "windows-sys",
+]
+
 [[package]]
 name = "termtree"
 version = "0.2.4"
@@ -354,7 +424,7 @@ version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b1141d4d61095b28419e22cb0bbf02755f5e54e0526f97f1e3d1d160e60885fb"
 dependencies = [
- "terminal_size",
+ "terminal_size 0.1.17",
 ]
 
 [[package]]
@@ -428,3 +498,46 @@ name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
+
+[[package]]
+name = "windows-sys"
+version = "0.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ea04155a16a59f9eab786fe12a4a450e75cdb175f9e0d80da1e17db09f55b8d2"
+dependencies = [
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9bb8c3fd39ade2d67e9874ac4f3db21f0d710bee00fe7cab16949ec184eeaa47"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "180e6ccf01daf4c426b846dfc66db1fc518f074baa793aa7d9b9aaeffad6a3b6"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2e7917148b2812d1eeafaeb22a97e4813dfa60a3f8f78ebe204bcc88f12f024"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4dcd171b8776c41b97521e5da127a2d86ad280114807d0b2ab1e462bc764d9e1"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.36.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c811ca4a8c853ef420abd8592ba53ddbbac90410fab6903b3e79972a631f7680"

Cargo.toml

@@ -17,6 +17,7 @@ atty = "0.2"
 const_format = "0.2"
 libc = "0.2"
 thiserror = "1.0"
+terminal_size = "0.2"
 
 [dependencies.clap]
 version = "3"

src/bin/hexyl.rs

@@ -4,7 +4,7 @@ extern crate clap;
 use std::convert::TryFrom;
 use std::fs::File;
 use std::io::{self, prelude::*, SeekFrom};
-use std::num::{NonZeroI64, NonZeroU8};
+use std::num::{NonZeroI64, NonZeroU16, NonZeroU8};
 
 use clap::{crate_name, crate_version, AppSettings, Arg, ColorChoice, Command};
 
@@ -16,6 +16,8 @@ use const_format::formatcp;
 
 use thiserror::Error as ThisError;
 
+use terminal_size::terminal_size;
+
 use hexyl::{BorderStyle, Input, Printer};
 
 const DEFAULT_BLOCK_SIZE: i64 = 512;
@@ -160,6 +162,31 @@ fn run() -> Result<(), AnyhowError> {
                     "Sets the number of hex data columns to be displayed. \
                     Cannot be used with other width-setting options.",
                 ),
+        )
+        .arg(
+            Arg::new("terminal_width")
+                .short('t')
+                .long("terminal-width")
+                .takes_value(true)
+                .value_name("N")
+                .conflicts_with("columns")
+                .help(
+                    "Sets the number of terminal columns to be displayed.\nSince the terminal \
+                    width may not be an evenly divisible by the width per hex data column, this \
+                    will use the greatest number of hex data columns that can fit in the requested \
+                    width but still leave some space to the right.\nCannot be used with other \
+                    width-setting options.",
+                ),
+        )
+        .arg(
+            Arg::new("auto_width")
+                .short('a')
+                .long("auto-width")
+                .conflicts_with_all(&["columns", "terminal_width"])
+                .help(
+                    "Sets the number of hex data columns to be adjusted according to the \
+                    detected terminal width.\nCannot be used with other width-setting options.",
+                ),
         );
 
     let matches = command.get_matches();
@@ -278,7 +305,7 @@ fn run() -> Result<(), AnyhowError> {
         .transpose()?
         .unwrap_or(0);
 
-    let columns = matches
+    let columns = if let Some(columns) = matches
         .value_of("columns")
         .map(|s| {
             s.parse::<NonZeroU8>().map(u8::from).context(anyhow!(
@@ -287,7 +314,40 @@ fn run() -> Result<(), AnyhowError> {
             ))
         })
         .transpose()?
-        .unwrap_or(2);
+    {
+        columns
+    } else {
+        let terminal_width = if let Some(terminal_width) = matches
+            .value_of("terminal_width")
+            .map(|s| {
+                s.parse::<NonZeroU16>().map(u16::from).context(anyhow!(
+                    "failed to parse `--columns` arg {:?} as unsigned nonzero integer",
+                    s
+                ))
+            })
+            .transpose()?
+        {
+            Some(terminal_width)
+        } else if matches.is_present("auto_width") {
+            Some(terminal_size().expect("not a tty").0 .0)
+        } else {
+            None
+        };
+
+        if let Some(terminal_width) = terminal_width {
+            let offset = if show_position_panel { 10 } else { 1 };
+            let col_width = if show_char_panel { 35 } else { 26 };
+            if (terminal_width - offset) / col_width < 1 {
+                1
+            } else {
+                ((terminal_width - offset) / col_width)
+                    .try_into()
+                    .expect("there is a maximum of 255 columns")
+            }
+        } else {
+            2
+        }
+    };
 
     let stdout = io::stdout();
     let mut stdout_lock = stdout.lock();