File: dog.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 # dog [options...] [paths/URIs...] 27 # 28 # Dog fetches data from the named sources given to it, whether these are 29 # filenames or URIs. Single dashes stand for standard input, and can't be 30 # used more than once. When no names are given, stdin is read by default. 31 # 32 # A line-mode is available via leading option `-l`, or its aliases `--l`, 33 # `-lines`, and `--lines`. This mode turns all CRLF byte-pairs into single 34 # LF bytes, and ensures all non-empty inputs end with a final LF byte, 35 # which avoids accidentally joining lines across different inputs. 36 # 37 # Line-mode also ignores leading UTF-8 BOMs on each input's first line. 38 39 40 # fix_lines ensures CRLF byte-pairs become single LF bytes, and that 41 # leading UTF-8 BOMs on the first lines of each input are ignored 42 fix_lines() { 43 awk 'FNR == 1 { gsub(/^\xef\xbb\xbf/, "") } 1' | sed -E 's-\r$--' 44 } 45 46 # fail quits the script right after showing the message given, using 47 # exit code given as its 2nd arg 48 fail() { 49 printf "\x1b[31m%s\x1b[0m\n" "$1" > /dev/stderr 50 exit "$2" 51 } 52 53 # when no args are given, just show the help message and quit 54 if [ $# -eq 0 ]; then 55 fix_lines 56 exit $? 57 fi 58 59 # handle leading options 60 lines=0 61 case "$1" in 62 -h|--h|-help|--help) 63 # show help message, extracting the info-comment at the start 64 # of this file, and quit 65 awk '/^# +dog/, /^$/ { gsub(/^# ?/, ""); print }' "$0" 66 exit 0 67 ;; 68 -l|--l|-lines|--lines) 69 # enable line-mode 70 lines=1 71 # don't confuse this option as a named input, later on 72 shift 73 ;; 74 esac 75 76 # ensure single dashes aren't used multiple times 77 dashes=0 78 for a in "$@"; do 79 if [ "$a" = "-" ]; then 80 if [ "$dashes" -gt 0 ]; then 81 fail "can't use stdin (single-dash) more than once" 1 82 fi 83 dashes=1 84 fi 85 done 86 87 # ensure errors propagate correctly, even when in line-mode 88 # set -o pipefail 89 90 for a in "$@"; do 91 case "$a" in 92 -) 93 # handle a dash by reading from stdin 94 if [ "$lines" -eq 1 ]; then 95 fix_lines || exit $? 96 else 97 cat || exit $? 98 fi 99 ;; 100 101 dict://*|file://*|ftp://*|ftps://*|gopher://*|gophers://*|\ 102 http://*|https://*|rtmp://*|rtsp://*|scp://*|sftp://*|\ 103 smb://*|smbs://*|telnet://*|tftp://*) 104 # handle URIs 105 if [ "$lines" -eq 1 ]; then 106 (curl -s -L "$a" | fix_lines) || \ 107 fail "failed to fetch URI $a" $? 108 else 109 curl -s -L "$a" || fail "failed to fetch URI $a" $? 110 fi 111 ;; 112 113 data:*) 114 # handle data-URIs 115 if [ "$lines" -eq 1 ]; then 116 (printf "%s" "$a" | sed 's-^.*,--1' | base64 -d | awk 1) || \ 117 fail "failed to decode data-URI $a" $? 118 else 119 (printf "%s" "$a" | sed 's-^.*,--1' | base64 -d) || \ 120 fail "failed to decode data-URI $a" $? 121 fi 122 ;; 123 124 *) 125 # handle files and bytes-mode data-URIs 126 if [ "$lines" -eq 1 ]; then 127 (cat "$a" | fix_lines) || fail "failed to open file $a" $? 128 else 129 cat "$a" || fail "failed to open file $a" $? 130 fi 131 ;; 132 esac 133 done