Fix #254

Co-authored-by: David Peter <sharkdp@users.noreply.github.com>

.github/workflows/CICD.yml

@@ -1,7 +1,7 @@
 name: CICD
 
 env:
-  MIN_SUPPORTED_RUST_VERSION: "1.56.0"
+  MIN_SUPPORTED_RUST_VERSION: "1.56.1"
   CICD_INTERMEDIATES_DIR: "_cicd-intermediates"
 
 on:

Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "aho-corasick"
@@ -20,6 +20,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "anstyle"
+version = "1.0.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5192cca8006f1fd4f7237516f40fa183bb07f8fbdfedaa0036de5ea9b0b45e78"
+
 [[package]]
 name = "anyhow"
 version = "1.0.57"
@@ -28,13 +34,14 @@ checksum = "08f9b8508dccb7687a1d6c4ce66b2b0ecef467c94667de27d8d7fe1f8d2a9cdc"
 
 [[package]]
 name = "assert_cmd"
-version = "2.0.4"
+version = "2.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "93ae1ddd39efd67689deb1979d80bad3bf7f2b09c6e6117c8d1f2443b5e2f83e"
+checksum = "9c5bcfa8749ac45dd12cb11055aeeb6b27a3895560d60d71e3c23bf979e60514"
 dependencies = [
+ "anstyle",
  "bstr",
- "doc-comment",
+ "libc",
- "predicates",
+ "predicates 3.1.4",
  "predicates-core",
  "predicates-tree",
  "wait-timeout",
@@ -65,37 +72,43 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bstr"
-version = "0.2.17"
+version = "1.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ba3569f383e8f1598449f1a423e72e99569137b47740b1da11ef19af3d5c3223"
+checksum = "63044e1ae8e69f3b5a92c736ca6269b8d12fa7efe39bf34ddb06d102cf0e2cab"
 dependencies = [
- "lazy_static",
  "memchr",
  "regex-automata",
+ "serde",
 ]
 
 [[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",
 ]
@@ -126,18 +139,33 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
 
-[[package]]
-name = "doc-comment"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
-
 [[package]]
 name = "either"
 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"
@@ -173,7 +201,8 @@ dependencies = [
  "clap",
  "const_format",
  "libc",
- "predicates",
+ "predicates 2.1.1",
+ "terminal_size 0.2.1",
  "thiserror",
 ]
 
@@ -187,6 +216,12 @@ 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"
@@ -197,22 +232,22 @@ dependencies = [
 ]
 
 [[package]]
-name = "lazy_static"
+name = "libc"
-version = "1.4.0"
+version = "0.2.182"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
+checksum = "6800badb6cb2082ffd7b6a67e6125bb39f18782f793520caee8cb8846be06112"
 
 [[package]]
-name = "libc"
+name = "linux-raw-sys"
-version = "0.2.126"
+version = "0.0.46"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "349d5a591cd28b49e1d1037471617a32ddcda5731b99419008085f72d5a53836"
+checksum = "d4d2456c373231a208ad294c33dc5bff30051eafd954cd4caae83a712b12854d"
 
 [[package]]
 name = "memchr"
-version = "2.5.0"
+version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
+checksum = "f8ca58f447f06ed17d5fc4043ce1b10dd205e060fb3ce5b979b8ed8e59ff3f79"
 
 [[package]]
 name = "normalize-line-endings"
@@ -229,6 +264,12 @@ 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"
@@ -250,10 +291,21 @@ dependencies = [
 ]
 
 [[package]]
-name = "predicates-core"
+name = "predicates"
-version = "1.0.3"
+version = "3.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "da1c2388b1513e1b605fcec39a95e0a9e8ef088f71443ef37099fa9ae6673fcb"
+checksum = "ada8f2932f28a27ee7b70dd6c1c39ea0675c55a36879ab92f3a715eaa1e63cfe"
+dependencies = [
+ "anstyle",
+ "difflib",
+ "predicates-core",
+]
+
+[[package]]
+name = "predicates-core"
+version = "1.0.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cad38746f3166b4031b1a0d39ad9f954dd291e7854fcc0eed52ee41a0b50d144"
 
 [[package]]
 name = "predicates-tree"
@@ -296,9 +348,9 @@ dependencies = [
 
 [[package]]
 name = "regex-automata"
-version = "0.1.10"
+version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6c230d73fb8d8c1b9c0b3135c5142a8acee3a0558fb8db5cf1cb65f8d7862132"
+checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
 
 [[package]]
 name = "regex-syntax"
@@ -306,6 +358,26 @@ 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 = "serde"
+version = "1.0.185"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "be9b6f69f1dfd54c3b568ffa45c310d6973a5e5148fd40cf515acaf38cf5bc31"
+
 [[package]]
 name = "strsim"
 version = "0.10.0"
@@ -342,6 +414,16 @@ 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 +436,7 @@ 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 +510,46 @@ 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"
@@ -24,7 +25,7 @@ default-features = false
 features = ["std", "suggestions", "color", "wrap_help", "cargo"]
 
 [dev-dependencies]
-assert_cmd = "2.0"
+assert_cmd = "2.1"
 predicates = "2.0"
 
 [profile.release]

examples/simple.rs

@@ -16,6 +16,7 @@ fn main() {
     let show_position_panel = true;
     let use_squeezing = false;
     let border_style = BorderStyle::Unicode;
+    let columns = 2;
 
     let mut printer = Printer::new(
         &mut handle,
@@ -24,6 +25,7 @@ fn main() {
         show_position_panel,
         border_style,
         use_squeezing,
+        columns,
     );
     printer.print_all(&input[..]).unwrap();
 }

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;
+use std::num::{NonZeroI64, NonZeroU16};
 
 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;
@@ -149,6 +151,42 @@ fn run() -> Result<(), AnyhowError> {
                     A negative value is valid and calculates an offset relative to the \
                     end of the file.",
                 ),
+        )
+        .arg(
+            Arg::new("columns")
+                .short('w')
+                .long("columns")
+                .takes_value(true)
+                .value_name("N")
+                .help(
+                    "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();
@@ -267,6 +305,48 @@ fn run() -> Result<(), AnyhowError> {
         .transpose()?
         .unwrap_or(0);
 
+    let columns = if let Some(columns) = matches
+        .value_of("columns")
+        .map(|s| {
+            s.parse::<NonZeroU16>().map(u16::from).context(anyhow!(
+                "failed to parse `--columns` arg {:?} as unsigned nonzero integer",
+                s
+            ))
+        })
+        .transpose()?
+    {
+        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().ok_or_else(|| anyhow!("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
+            }
+        } else {
+            2
+        }
+    };
+
     let stdout = io::stdout();
     let mut stdout_lock = stdout.lock();
 
@@ -277,6 +357,7 @@ fn run() -> Result<(), AnyhowError> {
         show_position_panel,
         border_style,
         squeeze,
+        columns,
     );
     printer.display_offset(skip_offset + display_offset);
     printer.print_all(&mut reader).map_err(|e| anyhow!(e))?;

src/lib.rs

@@ -154,6 +154,8 @@ pub struct Printer<'a, Writer: Write> {
     byte_char_panel: Vec<String>,
     squeezer: Squeezer,
     display_offset: u64,
+    /// The number of panels to draw.
+    columns: u16,
 }
 
 impl<'a, Writer: Write> Printer<'a, Writer> {
@@ -164,6 +166,7 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
         show_position_panel: bool,
         border_style: BorderStyle,
         use_squeeze: bool,
+        columns: u16,
     ) -> Printer<'a, Writer> {
         Printer {
             idx: 1,
@@ -175,7 +178,7 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
             show_position_panel,
             border_style,
             header_was_printed: false,
-            byte_hex_panel: (0u8..=u8::max_value())
+            byte_hex_panel: (0u8..=u8::MAX)
                 .map(|i| {
                     let byte_hex = format!("{:02x} ", i);
                     if show_color {
@@ -187,7 +190,7 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
                 .collect(),
             byte_char_panel: show_char_panel
                 .then(|| {
-                    (0u8..=u8::max_value())
+                    (0u8..=u8::MAX)
                         .map(|i| {
                             let byte_char = format!("{}", Byte(i).as_char());
                             if show_color {
@@ -199,8 +202,9 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
                         .collect()
                 })
                 .unwrap_or_default(),
-            squeezer: Squeezer::new(use_squeeze),
+            squeezer: Squeezer::new(use_squeeze, 8 * columns as u64),
             display_offset: 0,
+            columns,
         }
     }
 
@@ -223,10 +227,20 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
             write!(self.writer, "{}", l).ok();
         }
 
-        write!(self.writer, "{h25}{c}{h25}", c = c, h25 = h25).ok();
+        for _ in 0..self.columns - 1 {
+            write!(self.writer, "{h25}{c}", h25 = h25, c = c).ok();
+        }
+        if self.show_char_panel {
+            write!(self.writer, "{h25}{c}", h25 = h25, c = c).ok();
+        } else {
+            write!(self.writer, "{h25}", h25 = h25).ok();
+        }
 
         if self.show_char_panel {
-            writeln!(self.writer, "{c}{h8}{c}{h8}{r}", c = c, h8 = h8, r = r).ok();
+            for _ in 0..self.columns - 1 {
+                write!(self.writer, "{h8}{c}", h8 = h8, c = c).ok();
+            }
+            writeln!(self.writer, "{h8}{r}", h8 = h8, r = r).ok();
         } else {
             writeln!(self.writer, "{r}", r = r).ok();
         }
@@ -287,36 +301,30 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
                 self.byte_char_panel[b as usize]
             );
 
-            if idx == 8 {
+            if idx % 8 == 0 && idx % (u64::from(self.columns) * 8) != 0 {
                 let _ = write!(&mut self.buffer_line, "{}", self.border_style.inner_sep());
             }
 
             idx += 1;
         }
 
-        if len < 8 {
+        if len < usize::from(8 * self.columns) {
-            let _ = writeln!(
+            let _ = write!(&mut self.buffer_line, "{0:1$}", "", 8 - len % 8);
-                &mut self.buffer_line,
+            for _ in 0..(usize::from(8 * self.columns) - (len + (8 - len % 8))) / 8 {
-                "{0:1$}{3}{0:2$}{4}",
+                let _ = write!(
-                "",
+                    &mut self.buffer_line,
-                8 - len,
+                    "{2}{0:1$}",
-                8,
+                    "",
-                self.border_style.inner_sep(),
+                    8,
-                self.border_style.outer_sep(),
+                    self.border_style.inner_sep()
-            );
+                );
-        } else {
+            }
-            let _ = writeln!(
-                &mut self.buffer_line,
-                "{0:1$}{2}",
-                "",
-                16 - len,
-                self.border_style.outer_sep()
-            );
         }
+        let _ = writeln!(&mut self.buffer_line, "{}", self.border_style.outer_sep());
     }
 
     pub fn print_byte(&mut self, b: u8) -> io::Result<()> {
-        if self.idx % 16 == 1 {
+        if self.idx % (u64::from(self.columns) * 8) == 1 {
             self.print_header();
             self.print_position_panel();
         }
@@ -326,14 +334,10 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
 
         self.squeezer.process(b, self.idx);
 
-        match self.idx % 16 {
+        if self.idx % (u64::from(self.columns) * 8) == 0 {
-            8 => {
+            self.print_textline()?;
-                let _ = write!(&mut self.buffer_line, "{} ", self.border_style.inner_sep());
+        } else if self.idx % 8 == 0 {
-            }
+            let _ = write!(&mut self.buffer_line, "{} ", self.border_style.inner_sep());
-            0 => {
-                self.print_textline()?;
-            }
-            _ => {}
         }
 
         self.idx += 1;
@@ -347,16 +351,33 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
         if len == 0 {
             if self.squeezer.active() {
                 self.print_position_panel();
-                let _ = writeln!(
+                write!(&mut self.buffer_line, "{0:1$}", "", 24)?;
+                for _ in 0..self.columns - 1 {
+                    write!(
+                        &mut self.buffer_line,
+                        "{2}{0:1$}",
+                        "",
+                        25,
+                        self.border_style.inner_sep()
+                    )?;
+                }
+                write!(
                     &mut self.buffer_line,
-                    "{0:1$}{4}{0:2$}{5}{0:3$}{4}{0:3$}{5}",
+                    "{2}{0:1$}",
                     "",
-                    24,
-                    25,
                     8,
-                    self.border_style.inner_sep(),
+                    self.border_style.outer_sep()
-                    self.border_style.outer_sep(),
+                )?;
-                );
+                for _ in 0..self.columns - 1 {
+                    write!(
+                        &mut self.buffer_line,
+                        "{2}{0:1$}",
+                        "",
+                        8,
+                        self.border_style.inner_sep()
+                    )?;
+                }
+                writeln!(&mut self.buffer_line, "{}", self.border_style.outer_sep())?;
                 self.writer.write_all(&self.buffer_line)?;
             }
             return Ok(());
@@ -364,28 +385,22 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
 
         let squeeze_action = self.squeezer.action();
 
+        // print empty space on last line
         if squeeze_action != SqueezeAction::Delete {
-            if len < 8 {
+            if len < usize::from(8 * self.columns) {
-                let _ = write!(
+                write!(&mut self.buffer_line, "{0:1$}", "", 3 * (8 - len % 8))?;
-                    &mut self.buffer_line,
+                for _ in 0..(usize::from(8 * self.columns) - (len + (8 - len % 8))) / 8 {
-                    "{0:1$}{3}{0:2$}{4}",
+                    write!(
-                    "",
+                        &mut self.buffer_line,
-                    3 * (8 - len),
+                        "{2}{0:1$}",
-                    1 + 3 * 8,
+                        "",
-                    self.border_style.inner_sep(),
+                        1 + 3 * 8,
-                    self.border_style.outer_sep(),
+                        self.border_style.inner_sep()
-                );
+                    )?;
-            } else {
+                }
-                let _ = write!(
-                    &mut self.buffer_line,
-                    "{0:1$}{2}",
-                    "",
-                    3 * (16 - len),
-                    self.border_style.outer_sep()
-                );
             }
+            write!(&mut self.buffer_line, "{}", self.border_style.outer_sep())?;
         }
-
         self.print_char_panel();
 
         match squeeze_action {
@@ -397,17 +412,33 @@ impl<'a, Writer: Write> Printer<'a, Writer> {
                 } else {
                     String::from("*")
                 };
-                let _ = writeln!(
+
+                write!(
                     &mut self.buffer_line,
-                    "{5}{0}{1:2$}{5}{1:3$}{6}{1:3$}{5}{1:4$}{6}{1:4$}{5}",
+                    "{3}{0}{1:2$}{3}",
                     asterisk,
                     "",
                     7,
-                    25,
+                    self.border_style.outer_sep()
-                    8,
+                )?;
-                    self.border_style.outer_sep(),
+
-                    self.border_style.inner_sep(),
+                for i in 0..self.columns {
-                );
+                    write!(&mut self.buffer_line, "{0:1$}", "", 25)?;
+                    if i != self.columns - 1 {
+                        write!(&mut self.buffer_line, "{}", self.border_style.inner_sep())?;
+                    } else {
+                        write!(&mut self.buffer_line, "{}", self.border_style.outer_sep())?;
+                    }
+                }
+
+                for i in 0..self.columns {
+                    write!(&mut self.buffer_line, "{0:1$}", "", 8)?;
+                    if i != self.columns - 1 {
+                        write!(&mut self.buffer_line, "{}", self.border_style.inner_sep())?;
+                    } else {
+                        writeln!(&mut self.buffer_line, "{}", self.border_style.outer_sep())?;
+                    }
+                }
             }
             SqueezeAction::Delete => self.buffer_line.clear(),
             SqueezeAction::Ignore => (),
@@ -484,7 +515,15 @@ mod tests {
 
     fn assert_print_all_output<Reader: Read>(input: Reader, expected_string: String) {
         let mut output = vec![];
-        let mut printer = Printer::new(&mut output, false, true, true, BorderStyle::Unicode, true);
+        let mut printer = Printer::new(
+            &mut output,
+            false,
+            true,
+            true,
+            BorderStyle::Unicode,
+            true,
+            2,
+        );
 
         printer.print_all(input).unwrap();
 
@@ -528,8 +567,15 @@ mod tests {
         .to_owned();
 
         let mut output = vec![];
-        let mut printer: Printer<Vec<u8>> =
+        let mut printer: Printer<Vec<u8>> = Printer::new(
-            Printer::new(&mut output, false, true, true, BorderStyle::Unicode, true);
+            &mut output,
+            false,
+            true,
+            true,
+            BorderStyle::Unicode,
+            true,
+            2,
+        );
         printer.display_offset(0xdeadbeef);
 
         printer.print_all(input).unwrap();
@@ -537,4 +583,34 @@ mod tests {
         let actual_string: &str = str::from_utf8(&output).unwrap();
         assert_eq!(actual_string, expected_string)
     }
+
+    #[test]
+    fn multiple_columns() {
+        let input = io::Cursor::new(b"supercalifragilisticexpialidocioussupercalifragilisticexpialidocioussupercalifragilisticexpialidocious");
+        let expected_string = "\
+┌────────┬─────────────────────────┬─────────────────────────┬─────────────────────────┬─────────────────────────┬────────┬────────┬────────┬────────┐
+│00000000│ 73 75 70 65 72 63 61 6c ┊ 69 66 72 61 67 69 6c 69 ┊ 73 74 69 63 65 78 70 69 ┊ 61 6c 69 64 6f 63 69 6f │supercal┊ifragili┊sticexpi┊alidocio│
+│00000020│ 75 73 73 75 70 65 72 63 ┊ 61 6c 69 66 72 61 67 69 ┊ 6c 69 73 74 69 63 65 78 ┊ 70 69 61 6c 69 64 6f 63 │ussuperc┊alifragi┊listicex┊pialidoc│
+│00000040│ 69 6f 75 73 73 75 70 65 ┊ 72 63 61 6c 69 66 72 61 ┊ 67 69 6c 69 73 74 69 63 ┊ 65 78 70 69 61 6c 69 64 │ioussupe┊rcalifra┊gilistic┊expialid│
+│00000060│ 6f 63 69 6f 75 73       ┊                         ┊                         ┊                         │ocious  ┊        ┊        ┊        │
+└────────┴─────────────────────────┴─────────────────────────┴─────────────────────────┴─────────────────────────┴────────┴────────┴────────┴────────┘
+"
+        .to_owned();
+
+        let mut output = vec![];
+        let mut printer: Printer<Vec<u8>> = Printer::new(
+            &mut output,
+            false,
+            true,
+            true,
+            BorderStyle::Unicode,
+            true,
+            4,
+        );
+
+        printer.print_all(input).unwrap();
+
+        let actual_string: &str = str::from_utf8(&output).unwrap();
+        assert_eq!(actual_string, expected_string)
+    }
 }

src/squeezer.rs

@@ -22,6 +22,7 @@ enum SqueezeState {
 pub struct Squeezer {
     state: SqueezeState,
     byte: u8,
+    lsize: u64,
 }
 
 #[derive(Debug, PartialEq)]
@@ -31,11 +32,8 @@ pub enum SqueezeAction {
     Delete,
 }
 
-/// line size
-const LSIZE: u64 = 16;
-
 impl Squeezer {
-    pub fn new(enabled: bool) -> Squeezer {
+    pub fn new(enabled: bool, lsize: u64) -> Squeezer {
         Squeezer {
             state: if enabled {
                 SqueezeState::Probe
@@ -43,6 +41,7 @@ impl Squeezer {
                 SqueezeState::Disabled
             },
             byte: 0,
+            lsize,
         }
     }
 
@@ -53,7 +52,7 @@ impl Squeezer {
         }
         let eq = b == self.byte;
 
-        if i % LSIZE == 0 {
+        if i % self.lsize == 0 {
             if !eq {
                 self.state = Probe;
             } else {
@@ -68,9 +67,9 @@ impl Squeezer {
                 };
             }
         } else if !eq {
-            if i % LSIZE == 1 {
+            if i % self.lsize == 1 {
                 self.state = Probe;
-            } else if i % LSIZE != 1 {
+            } else if i % self.lsize != 1 {
                 self.state = NoSqueeze;
             }
         }
@@ -111,13 +110,14 @@ impl Squeezer {
 mod tests {
     use super::*;
 
+    const LSIZE: u64 = 16;
     const LSIZE_USIZE: usize = LSIZE as usize;
 
     #[test]
     fn three_same_lines() {
         const LINES: usize = 3;
         let v = vec![0u8; LINES * LSIZE_USIZE];
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -144,7 +144,7 @@ mod tests {
     fn incomplete_while_squeeze() {
         // fourth line only has 12 bytes and should be printed
         let v = vec![0u8; 3 * LSIZE_USIZE + 12];
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -175,7 +175,7 @@ mod tests {
         v.extend(vec![1u8; 16]);
         v.extend(vec![2u8; 16]);
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -206,7 +206,7 @@ mod tests {
         let mut v = vec![0u8; (LINES - 1) * LSIZE_USIZE];
         v.extend(vec![1u8; 16]);
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -237,7 +237,7 @@ mod tests {
         v.extend(vec![0u8; 8]);
         v.extend(vec![1u8; 8]);
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -270,7 +270,7 @@ mod tests {
         v.extend(vec![0u8; 8]);
         v.extend(vec![1u8; 8]);
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -309,7 +309,7 @@ mod tests {
         v.extend(vec![20u8; 16]); // print
         v.extend(vec![0u8; 12]); // print, only 12 bytes
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -351,7 +351,7 @@ mod tests {
         v.extend(vec![20u8; 16]);
         v.extend(vec![20u8; 16]);
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();
@@ -383,7 +383,7 @@ mod tests {
         v.extend(vec![20u8; 15]);
         v.extend(vec![20u8; 16]);
 
-        let mut s = Squeezer::new(true);
+        let mut s = Squeezer::new(true, LSIZE);
         // just initialized
         assert_eq!(s.action(), SqueezeAction::Ignore);
         s.advance();

tests/integration_tests.rs

@@ -1,7 +1,7 @@
 use assert_cmd::Command;
 
 fn hexyl() -> Command {
-    let mut cmd = Command::cargo_bin("hexyl").unwrap();
+    let mut cmd = Command::new(assert_cmd::cargo_bin!("hexyl"));
     cmd.current_dir("tests/examples");
     cmd
 }