+#!/bin/bash
+
+# tmux requires unrecognized OSC sequences to be wrapped with DCS tmux;
+# <sequence> ST, and for all ESCs in <sequence> to be replaced with ESC ESC. It
+# only accepts ESC backslash for ST. We use TERM instead of TMUX because TERM
+# gets passed through ssh.
+function print_osc() {
+ if [[ $TERM == screen* ]] ; then
+ printf "\033Ptmux;\033\033]"
+ else
+ printf "\033]"
+ fi
+}
+
+# More of the tmux workaround described above.
+function print_st() {
+ if [[ $TERM == screen* ]] ; then
+ printf "\a\033\\"
+ else
+ printf "\a"
+ fi
+}
+
+# print_image filename inline base64contents print_filename
+# filename: Filename to convey to client
+# inline: 0 or 1
+# base64contents: Base64-encoded contents
+# print_filename: If non-empty, print the filename
+# before outputting the image
+function print_image() {
+ print_osc
+ printf '1337;File='
+ if [[ -n "$1" ]]; then
+ printf 'name='`printf "%s" "$1" | base64`";"
+ fi
+
+ VERSION=$(base64 --version 2>&1)
+ if [[ "$VERSION" =~ fourmilab ]]; then
+ BASE64ARG=-d
+ elif [[ "$VERSION" =~ GNU ]]; then
+ BASE64ARG=-di
+ else
+ BASE64ARG=-D
+ fi
+
+ printf "%s" "$3" | base64 $BASE64ARG | wc -c | awk '{printf "size=%d",$1}'
+ printf ";inline=$2"
+ printf ":"
+ printf "%s" "$3"
+ print_st
+ printf '\n'
+ if [[ -n "$4" ]]; then
+ echo $1
+ fi
+}
+
+function error() {
+ echo "ERROR: $*" 1>&2
+}
+
+function show_help() {
+ echo "Usage: imgcat [-p] filename ..." 1>& 2
+ echo " or: cat filename | imgcat" 1>& 2
+}
+
+function check_dependency() {
+ if ! (builtin command -V "$1" > /dev/null 2>& 1); then
+ echo "imgcat: missing dependency: can't find $1" 1>& 2
+ exit 1
+ fi
+}
+
+## Main
+
+if [ -t 0 ]; then
+ has_stdin=f
+else
+ has_stdin=t
+fi
+
+# Show help if no arguments and no stdin.
+if [ $has_stdin = f -a $# -eq 0 ]; then
+ show_help
+ exit
+fi
+
+check_dependency awk
+check_dependency base64
+check_dependency wc
+
+# Look for command line flags.
+while [ $# -gt 0 ]; do
+ case "$1" in
+ -h|--h|--help)
+ show_help
+ exit
+ ;;
+ -p|--p|--print)
+ print_filename=1
+ ;;
+ -u|--u|--url)
+ check_dependency curl
+ encoded_image=$(curl -s "$2" | base64) || (error "No such file or url $2"; exit 2)
+ has_stdin=f
+ print_image "$2" 1 "$encoded_image" "$print_filename"
+ set -- ${@:1:1} "-u" ${@:3}
+ if [ "$#" -eq 2 ]; then
+ exit
+ fi
+ ;;
+ -*)
+ error "Unknown option flag: $1"
+ show_help
+ exit 1
+ ;;
+ *)
+ if [ -r "$1" ] ; then
+ has_stdin=f
+ print_image "$1" 1 "$(base64 < "$1")" "$print_filename"
+ else
+ error "imgcat: $1: No such file or directory"
+ exit 2
+ fi
+ ;;
+ esac
+ shift
+done
+
+# Read and print stdin
+if [ $has_stdin = t ]; then
+ print_image "" 1 "$(cat | base64)" ""
+fi
+
+exit 0