File: catl.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 # catl [options...] [files...]
  27 #
  28 # Unlike `cat`, conCATenate Lines ensures no lines across inputs are
  29 # accidentally joined, since all lines it outputs end with line-feeds,
  30 # even when the original files don't.
  31 #
  32 # The options are, available both in single and double-dash versions
  33 #
  34 #   -h, -help    show this help message
  35 #   -0, -null    turn null-byte-delimited chunks into proper lines
  36 
  37 
  38 nulled=0
  39 buffered=0
  40 
  41 while [ $# -gt 0 ]; do
  42     case "$1" in
  43         -b|--b|-buffered|--buffered)
  44             buffered=1
  45             shift
  46             continue
  47         ;;
  48 
  49         -h|--h|-help|--help)
  50             awk '/^# +catl /, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  51             exit 0
  52         ;;
  53 
  54         -0|--0|-null|--null)
  55             nulled=1
  56             shift
  57             continue
  58         ;;
  59     esac
  60 
  61     break
  62 done
  63 
  64 [ "$1" = '--' ] && shift
  65 
  66 # show all non-existing files given
  67 failed=0
  68 for arg in "$@"; do
  69     if [ "${arg}" = "-" ]; then
  70         continue
  71     fi
  72     if [ ! -e "${arg}" ]; then
  73         printf "no file named \"%s\"\n" "${arg}" >&2
  74         failed=1
  75     fi
  76 done
  77 
  78 if [ "${failed}" -gt 0 ]; then
  79     exit 2
  80 fi
  81 
  82 flush=0
  83 if [ "${buffered}" -eq 0 ] && { [ -p /dev/stdout ] || [ -t 1 ]; }; then
  84     flush=1
  85 fi
  86 
  87 if [ "${nulled}" -eq 0 ]; then
  88     awk -v flush="${flush}" '{ print; if (flush) fflush() }' "$@"
  89 else
  90     awk -v RS='\000' -v flush="${flush}" '{ print; if (flush) fflush() }' "$@"
  91 fi