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