File: nhex.sh 1 #!/bin/sh 2 3 # The MIT License (MIT) 4 # 5 # Copyright (c) 2026 pacman64 6 # 7 # Permission is hereby granted, free of charge, to any person obtaining a copy 8 # of this software and associated documentation files (the "Software"), to deal 9 # in the Software without restriction, including without limitation the rights 10 # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 11 # copies of the Software, and to permit persons to whom the Software is 12 # furnished to do so, subject to the following conditions: 13 # 14 # The above copyright notice and this permission notice shall be included in 15 # all copies or substantial portions of the Software. 16 # 17 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 18 # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 19 # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 20 # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 21 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 22 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 23 # SOFTWARE. 24 25 26 # nhex [options...] [files...] 27 # 28 # Nice HEXadecimals is a byte-viewer which shows bytes as base-16 values, 29 # using various ANSI styles to color-code output. 30 # 31 # Output lines end with a panel showing all ASCII sequences detected along. 32 # 33 # Options, where leading double-dashes are also allowed: 34 # 35 # -h, -help show this help message 36 37 38 case "$1" in 39 -h|--h|-help|--help) 40 awk '/^# +nhex /, /^$/ { gsub(/^# ?/, ""); print }' "$0" 41 exit 0 42 ;; 43 esac 44 45 [ "$1" = '--' ] && shift 46 47 flush=0 48 if [ -p /dev/stdout ] || [ -t 1 ]; then 49 flush=1 50 fi 51 52 dashes=0 53 for name in "${@:--}"; do 54 if [ "${name}" = "-" ]; then 55 dashes="$((dashes + 1))" 56 fi 57 if [ "${dashes}" -gt 1 ]; then 58 printf "can't use dash/stdin multiple times\n" >&2 59 exit 1 60 fi 61 done 62 63 first=1 64 65 for name in "${@:--}"; do 66 od -v -A none -t u1 --width=16 "${name}" \ 67 | awk -v flush="${flush}" ' 68 NR > 1 { 69 for (i = 1; i <= pnf; i++) printf " %s", p[i] 70 for (i = 1; i <= pnf; i++) printf " %s", p[i] 71 for (i = 1; i <= NF; i++) printf " %s", $i 72 print "" 73 if (flush) fflush() 74 } 75 76 { 77 pnf = NF 78 for (i = 1; i <= NF; i++) p[i] = $i 79 } 80 81 END { 82 if (NR > 0) { 83 for (i = 1; i <= pnf; i++) printf " %s", p[i] 84 for (i = 1; i <= pnf; i++) printf " %s", p[i] 85 if (pnf > 0) print "" 86 } 87 }' \ 88 | awk -v flush="${flush}" -v first="${first}" -v name="${name}" ' 89 BEGIN { 90 vis1 = " !\"#$%& ()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ" 91 vis2 = "[\\]^_`abcdefghijklmnopqrstuvwxyz{|}~" 92 split(vis1 vis2, visible, "") 93 l = length(visible) 94 for (i = 1; i < l; i++) a[i + 32 - 1] = visible[i] 95 a[39] = "'"'"'" 96 a[126] = "~" 97 98 if (name == "-") name = "<stdin>" 99 if (!first) printf "\n\n" 100 printf "• %s\n\n", name; fflush() 101 } 102 103 function show_offset(n, s, len, lead, alt) { 104 s = sprintf("%8d", n) 105 106 while (match(s, /[0-9]{4,}/)) { 107 len = RLENGTH 108 lead = len % 3 109 alt = lead > 0 110 111 printf "%s", substr(s, 1, RSTART + lead - 1) 112 s = substr(s, RSTART + lead) 113 len -= lead 114 115 while (len > 0) { 116 if (alt == 1) { 117 printf "\x1b[38;5;248m%s\x1b[0m", substr(s, 1, 3) 118 } else { 119 printf "%s", substr(s, 1, 3) 120 } 121 122 alt = 1 - alt 123 s = substr(s, 4) 124 len -= 3 125 } 126 } 127 128 printf "%s", s 129 } 130 131 function show_byte(n) { 132 if (n == 0) { 133 printf "\x1b[38;5;111m%02x ", n 134 return 135 } 136 137 if (n == 255) { 138 printf "\x1b[38;5;209m%x ", n 139 return 140 } 141 142 if (32 <= n && n <= 126) { 143 printf "\x1b[38;5;72m%x\x1b[0m\x1b[48;5;254m%s", n, a[n] 144 return 145 } 146 147 printf "\x1b[38;5;246m%02x ", n 148 } 149 150 NR % 5 == 1 && NR > 1 { 151 printf "%8s ", "" 152 printf " · · · ·\n" 153 } 154 155 { 156 # printf "%8d \x1b[48;5;254m", offset 157 show_offset(offset) 158 printf " \x1b[48;5;254m" 159 160 for (i = 1; i <= NF; i++) { 161 if (i > 16) break 162 show_byte($i) 163 } 164 165 printf "\x1b[0m" 166 167 runs = 0 168 asciirun = 0 169 short = (NF < 2 * 16) 170 pad = short ? sprintf("%*s", 3 * (NF - 16) + 2, "") : " " 171 172 for (i = short ? NF / 2 : 16 + 1; i <= NF; i++) { 173 n = $i 174 175 if (32 < n && n <= 126) { 176 if (!asciirun) { 177 asciirun = 1 178 runs++ 179 printf (runs > 1) ? " " : pad 180 } 181 182 printf "%s", a[n] 183 continue 184 } 185 186 asciirun = 0 187 } 188 189 print "" 190 if (flush) fflush() 191 192 offset += 16 193 }' 194 195 first=0 196 done