File: get.sh
   1 #!/bin/sh
   2 
   3 # The MIT License (MIT)
   4 #
   5 # Copyright © 2024 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 # get [options...] [filepath/URI/data-URI...]
  27 #
  28 # Get data from the named source given, whether this is a filename, a URI,
  29 # or even a base64-encoded data-URI. Data-URIs are simply decoded into the
  30 # bytes they represent, no loading/fetching required.
  31 #
  32 # The only options show this help message, via any of `-h`, `--h`, `-help`,
  33 # or `--help`.
  34 
  35 
  36 # fail quits the script right after showing the message given, using
  37 # exit code given as its 2nd arg
  38 fail() {
  39     printf "\e[31m%s\e[0m\n" "$1" > /dev/stderr
  40     exit "${2:-1}"
  41 }
  42 
  43 if [ $# -eq 0 ]; then
  44     cat
  45     exit $?
  46 fi
  47 
  48 # if the argument given is an existing file, just use `cat`, even if the
  49 # name looks like a protocol presumably meant for `curl`
  50 if [ -e "$1" ]; then
  51     cat "$1"
  52     exit $?
  53 fi
  54 
  55 # handle leading options
  56 case "$1" in
  57     -h|--h|-help|--help)
  58         awk '/^# +get/, /^$/ { gsub(/^# ?/, ""); print }' "$0"
  59         exit 0
  60     ;;
  61 esac
  62 
  63 case "$1" in
  64     dict://*|ftp://*|ftps://*|gopher://*|gophers://*|http://*|https://*|\
  65     rtmp://*|rtsp://*|scp://*|sftp://*|smb://*|smbs://*|telnet://*|tftp://*)
  66         # handle URIs
  67         curl -s -L "$1" || fail "failed to fetch URI '$1'" $?
  68     ;;
  69 
  70     data:*)
  71         # handle data-URIs
  72         { printf "%s" "$1" | sed 's-^.{0,64},--1' | base64 -d; } || \
  73             fail "failed to decode data-URI '$1'" $?
  74     ;;
  75 
  76     file://*)
  77         # handle files
  78         cat "$(echo "$1" | sed 's-file://--1')" 2> /dev/null || \
  79             fail "failed to open file '$1'" $?
  80     ;;
  81 
  82     *)
  83         # handle files
  84         cat "$1" 2> /dev/null || fail "failed to open file '$1'" $?
  85     ;;
  86 esac