File: hawk.sh
   1 #!/bin/sh
   2 
   3 # The MIT License (MIT)
   4 #
   5 # Copyright © 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 # hawk [options...] [awk condition...] [filenames...]
  27 #
  28 #
  29 # Highlight (lines) satisfying an AWK condition/expression, keeping all other
  30 # lines the same. When not given a condition, all lines are highlighted.
  31 #
  32 # The handy case-insensitive shortcut options may cause this tool to fail, if
  33 # the main AWK tool installed doesn't support the special IGNORECASE variable.
  34 #
  35 # If /usr/bin/gawk is available, it becomes the AWK tool used: this ensures
  36 # support for case-insensitive matching, along with many other extras.
  37 #
  38 # The AWK options available only in single-dash versions are
  39 #
  40 #   -F fs               use `fs` for the field separator (the `FS` variable)
  41 #   -V                  show the AWK/GAWK version installed
  42 #   -v var=val          set a variable to a given value
  43 #
  44 # The other options are, available both in single and double-dash versions
  45 #
  46 #   -h, -help           show this help message
  47 #
  48 #   -ins                match regexes case-insensitively; fail if unsupported
  49 #   -insensitive        match regexes case-insensitively; fail if unsupported
  50 #
  51 #   -tsv                split fields using tabs, same as using -F "\t"
  52 #
  53 #   -blue               use a blue style
  54 #   -gray               use a gray style
  55 #   -green              use a green style
  56 #   -orange             use an orange style
  57 #   -purple             use a purple style
  58 #   -red                use a red style
  59 #
  60 #   -bb, -blueback      use a blue-background style
  61 #        -grayback      use a gray-background style
  62 #   -gb, -greenback     use a green-background style
  63 #   -ob, -orangeback    use an orange-background style
  64 #   -pb, -purpleback    use a purple-background style
  65 #   -rb, -redback       use a red-background style
  66 
  67 
  68 case "$1" in
  69     -h|--h|-help|--help)
  70         awk '/^# +hawk /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  71         exit 0
  72     ;;
  73 esac
  74 
  75 ansi='7m'
  76 command='awk'
  77 if [ -e /usr/bin/gawk ]; then
  78     command='/usr/bin/gawk'
  79 fi
  80 if [ -p /dev/stdout ] || [ -t 1 ]; then
  81     command='stdbuf -oL awk'
  82 fi
  83 
  84 case_insensitive=0
  85 
  86 while [ $# -gt 0 ]; do
  87     arg="$1"
  88 
  89     if [ "${arg}" = "--" ]; then
  90         shift
  91         break
  92     fi
  93 
  94     case "${arg}" in
  95         -F)
  96             shift
  97             if [ $# -eq 0 ]; then
  98                 printf "expected value after -F option\n" >&2
  99                 exit 1
 100             fi
 101             command="${command} -F "$1""
 102             shift
 103             continue
 104         ;;
 105 
 106         -F*)
 107             command="${command} ${arg}"
 108             shift
 109             continue
 110         ;;
 111 
 112         -v)
 113             shift
 114             if [ $# -eq 0 ]; then
 115                 printf "expected variable assignment after -v option\n" >&2
 116                 exit 1
 117             fi
 118             command="${command} -v "$1""
 119             shift
 120             continue
 121         ;;
 122 
 123         -ins|--ins|-insensitive|--insensitive)
 124             case_insensitive=1
 125             shift
 126             continue
 127         ;;
 128 
 129         -tsv|--tsv)
 130             command="${command} -F \"\\t\""
 131             shift
 132             continue
 133         ;;
 134 
 135         -blue|--blue)
 136             ansi='38;2;0;95;215m'
 137             shift
 138             continue
 139         ;;
 140 
 141         -bb|--bb|-blueback|--blueback)
 142             ansi='48;2;0;95;215m\x1b[38;2;238;238;238m'
 143             shift
 144             continue
 145         ;;
 146 
 147         -bold|--bold|-bolded|--bolded)
 148             ansi='1m'
 149             shift
 150             continue
 151         ;;
 152 
 153         -dim|--dim|-faint|--faint|-gray|--gray)
 154             ansi='38;2;168;168;168m'
 155             shift
 156             continue
 157         ;;
 158 
 159         -grayback|--grayback)
 160             ansi='48;2;168;168;168m\x1b[38;2;238;238;238m'
 161             shift
 162             continue
 163         ;;
 164 
 165         -green|--green)
 166             ansi='38;2;0;135;95m'
 167             shift
 168             continue
 169         ;;
 170 
 171         -gb|--gb|-greenback|--greenback)
 172             ansi='48;2;0;135;95m\x1b[38;2;238;238;238m'
 173             shift
 174             continue
 175         ;;
 176 
 177         -inv|--inv|-inverse|--inverse|-invert|--invert|-inverted|--inverted)
 178             ansi='7m'
 179             shift
 180             continue
 181         ;;
 182 
 183         -orange|--orange)
 184             ansi='38;2;215;95;0m'
 185             shift
 186             continue
 187         ;;
 188 
 189         -ob|--ob|-orangeback|--orangeback)
 190             ansi='48;2;215;95;0m\x1b[38;2;238;238;238m'
 191             shift
 192             continue
 193         ;;
 194 
 195         -purple|--purple)
 196             ansi='38;2;135;95;255m'
 197             shift
 198             continue
 199         ;;
 200 
 201         -pb|--pb|-purpleback|--purpleback)
 202             ansi='48;2;135;95;255m\x1b[38;2;238;238;238m'
 203             shift
 204             continue
 205         ;;
 206 
 207         -red|--red)
 208             ansi='38;2;204;0;0m'
 209             shift
 210             continue
 211         ;;
 212 
 213         -rb|--rb|-redback|--redback)
 214             ansi='48;2;204;0;0m\x1b[38;2;238;238;238m'
 215             shift
 216             continue
 217         ;;
 218 
 219         -strike|--strike|-striked|--striked|-stricken|--stricken)
 220             ansi='9m'
 221             shift
 222             continue
 223         ;;
 224 
 225         -underline|--underline|-underlined|--underlined)
 226             ansi='4m'
 227             shift
 228             continue
 229         ;;
 230 
 231         -*)
 232             command="${command} ${arg}"
 233             shift
 234             continue
 235         ;;
 236     esac
 237 
 238     break
 239 done
 240 
 241 cond="${1:-1}"
 242 [ $# -gt 0 ] && shift
 243 
 244 # show all non-existing files given
 245 failed=0
 246 for arg in "$@"; do
 247     if [ "${arg}" = "-" ]; then
 248         continue
 249     fi
 250     if [ ! -e "${arg}" ]; then
 251         printf "no file named \"%s\"\n" "${arg}" > /dev/stderr
 252         failed=1
 253     fi
 254 done
 255 
 256 if [ "${failed}" -gt 0 ]; then
 257     exit 2
 258 fi
 259 
 260 ci='
 261     BEGIN {
 262         if (IGNORECASE == "") {
 263             m = "your `awk` command lacks case-insensitive regex-matching"
 264             printf("\x1b[38;2;204;0;0m%s\x1b[0m\n", m) > "/dev/stderr"
 265             exit 125
 266         }
 267         IGNORECASE = 1
 268     }
 269 '
 270 if [ "${case_insensitive}" -eq 0 ]; then
 271     ci=''
 272 fi
 273 
 274 ${command} "${ci}"'
 275     '"${cond}"' {
 276         gsub(/\x1b\[0m/, "\x1b[0m\x1b['"${ansi}"'")
 277         printf "\x1b['"${ansi}"'%s\x1b[0m%s", $0, ORS
 278         next
 279     }
 280     1
 281 ' "$@"