From 44d4a78efa7cb464ec401f70475919559192e453 Mon Sep 17 00:00:00 2001
From: Dmitriy Tillyaev <kimapr@mail.ru>
Date: Wed, 4 Aug 2021 09:56:06 +0500
Subject: [PATCH] yes

---
 tstream | 188 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 188 insertions(+)
 create mode 100755 tstream

diff --git a/tstream b/tstream
new file mode 100755
index 0000000..69d3005
--- /dev/null
+++ b/tstream
@@ -0,0 +1,188 @@
+#!/bin/sh
+# Kimapr's streaming setup
+# how to use:
+# install ncat, lua (tested with 5.4.3), and script
+# mkdir ~/stream
+# make a text file ~/stream/welcome, it will be displayed on stream startup.
+# make a text file ~/stream/the_end, it will be displayed on stream end.
+# start the stream by running this script (see usage in the echo command below)
+# after it starts you can connect via the port provided from any interface
+# end the stream by exitting from the shell in the stream window
+# you can also replay past streams using `scriptreplay -O live -T live-timing` in ~/stream/hist/*/
+
+echo "usage: tstream <port> <width> <height> [max bandwidth in KiB/s (per-client)]"
+port=$1
+width=$2
+height=$3
+bandwidth=$4
+if [ "x$bandwidth" = "x" ]; then
+	bandwidth=32
+fi
+randid=`head -c 16 /dev/urandom | xxd -p`
+name=`date -u +%Y-%m-%d_%H-%M-%S_UTC`
+tmux new-session -d -s wstream_$randid "clear;cat ~/stream/welcome;$SHELL"
+tmux resize-window -t wstream_$randid -x $width -y $(($height - 1))
+tmux set-option -t wstream_$randid status-right "? viewers"
+cat >/tmp/tstream-helper_$randid <<EOF
+#!/bin/sh
+clear
+TMUX= tmux attach -t wstream_$randid
+clear
+cat ~/stream/the_end
+for i in \$(seq 7); do
+	echo -n .
+	sleep 0.1
+done
+echo DISCONNECT
+EOF
+chmod +x /tmp/tstream-helper_$randid
+mkdir -p ~/stream/hist/$name
+tmux new-session -d -s stream_$randid "SHELL='/tmp/tstream-helper_$randid' script -f ~/stream/hist/$name/live -T ~/stream/hist/$name/live-timing;sleep 2"
+tmux resize-window -t stream_$randid -x $width -y $height
+cat >/tmp/tstream-refresh_$randid <<EOF
+#!/usr/bin/env lua
+local file=io.popen("tmux list-clients")
+local lines={}
+local line=file:read()
+while line do
+	lines[#lines+1]=line
+	line=file:read()
+end
+local clients={}
+for k,v in ipairs(lines) do
+	local cl,sess=string.match(v,"(.-)%: (.-) ")
+	if sess=="wstream_$randid" then
+		os.execute("tmux refresh-client -t "..cl)
+	end
+end
+EOF
+echo 0 > /tmp/tstream-count_$randid
+vcrefresh="tmux set-option -t wstream_$randid status-right \"\$(cat /tmp/tstream-count_$randid) viewers\""
+sh -c "$vcrefresh"
+cat >/tmp/tstream-smarttail_$randid <<EOF
+#!/usr/bin/env lua
+local unpack=unpack or table.unpack
+local file=io.open("$HOME/stream/hist/$name/live")
+file:seek("end")
+local bandwidth=$bandwidth * 1024
+local checkpoints={}
+local coro=coroutine.create(function()
+	local file=io.open("/tmp/tstream-seektimes_$randid")
+	while true do
+		local curseek=file:seek()
+		local endseek=file:seek("end")
+		local avail=endseek-curseek
+		file:seek("set",curseek)
+		if avail>0 then
+			local str=file:read()
+			local seek,t=str:match("(.-) (.+)")
+			seek,t=tonumber(seek),tonumber(t)
+			if seek and t then
+				table.insert(checkpoints,{seek,t})
+			end
+		else
+			coroutine.yield()
+		end
+	end
+end)
+local ct=os.time()
+local count=0
+local counts={}
+while true do
+	local curseek=file:seek()
+	local endseek=file:seek("end")
+	local avail=endseek-curseek
+	file:seek("set",curseek)
+	assert(coroutine.resume(coro))
+	if avail>0 then
+		local str=file:read(math.min(avail,512))
+		assert(str)
+		io.write(str)
+		io.flush()
+		count=count+#str
+		local cpc=#checkpoints
+		local avg=0
+		for k,v in pairs(counts) do
+			avg=avg+v
+		end
+		avg=avg/#counts
+		if avg>bandwidth then
+			os.execute("clear")
+			print("overload! "..(avg/1024).." KiB/s > "..(bandwidth/1024).." KiB/s")
+			while true do
+				os.execute("sleep 0.1")
+				assert(coroutine.resume(coro))
+				if #checkpoints>cpc then
+					cpc=#checkpoints
+					break
+				end
+			end
+			local seek=checkpoints[cpc][1]
+			print("seeking to "..seek.."/"..file:seek("end"))
+			os.execute("sleep 1")
+			counts={}
+			count=0
+			file:seek("set",checkpoints[cpc][1]) --congestion
+		end
+	else
+		os.execute("sleep 0.01")
+	end
+	local tf=io.open("/tmp/tstream-death_$randid")
+	if tf then
+		tf:close()
+		io.stdin:close()
+		io.stdout:close()
+		return
+	end
+	local ct2=os.time()
+	if ct2~=ct then
+		ct=ct2
+		table.insert(counts,count)
+		count=0
+		while #counts>5 do
+			table.remove(counts,1)
+		end
+	end
+end
+EOF
+chmod +x /tmp/tstream-smarttail_$randid
+cat >/tmp/tstream-cat_$randid <<EOF
+#!/bin/sh
+vcrefresh='$vcrefresh'
+echo "\$vcrefresh"
+{ sleep 5;/tmp/tstream-refresh_$randid; } &
+echo "Welcome to Kimapr's stream. Please wait..."
+echo \$((\$(cat /tmp/tstream-count_$randid) + 1)) > /tmp/tstream-count_$randid
+sh -c "\$vcrefresh"
+/tmp/tstream-smarttail_$randid
+echo \$((\$(cat /tmp/tstream-count_$randid) - 1)) > /tmp/tstream-count_$randid
+sh -c "\$vcrefresh"
+EOF
+chmod +x /tmp/tstream-cat_$randid
+chmod +x /tmp/tstream-refresh_$randid
+touch /tmp/tstream-seektimes_$randid
+{
+	while true; do
+		sleep 5
+		echo "$(lua -e "local file=io.open(\"$HOME/stream/hist/$name/live\")print(file:seek(\"end\")..\" \"..os.time())file:close()")" >>/tmp/tstream-seektimes_$randid
+		/tmp/tstream-refresh_$randid
+	done
+} &
+ncat -l -k -c "/tmp/tstream-cat_$randid" $port &
+sleep 1
+tmux attach -t stream_$randid
+tmux kill-session -t wstream_$randid
+tmux kill-session -t stream_$randid
+touch /tmp/tstream-death_$randid
+echo PLEASE WAIT...
+sleep 2;
+rm /tmp/tstream-death_$randid
+rm /tmp/tstream-helper_$randid
+rm /tmp/tstream-refresh_$randid
+rm /tmp/tstream-cat_$randid
+rm /tmp/tstream-count_$randid
+rm /tmp/tstream-smarttail_$randid
+rm /tmp/tstream-seektimes_$randid
+kill %1
+kill %2
+echo exit complete