code: plan9front

ref: a14f9efa6848f167f54dea3e3823b31dae1461c9
dir: /rc/bin/rc-httpd/handlers/cgi/

#!/bin/rc
fn filter_headers{
	response=(200 OK)
	lines=''
	done=false
	while(~ $done false){
		line=`{getline}
		head=`{echo $line | awk '{print tolower($1)}'}
		if(~ $head status:*)
			response=`{echo $line | awk '{$1="" ; print}'}
		if not if(~ $line '')
			done=true
		if not
			lines=$"lines^$"line^$cr^'
'
	}
	echo 'HTTP/1.1' $"response^$cr
	echo -n $"lines
	do_log $response(1)
}

fn run_cgi {
	path=$cgi_path exec $"cgi_bin $params || echo 'Status: 500'
}

cgi_bin=$1
cgi_dir=.
if(! ~ $#* 1)
	cgi_dir=$*($#*)
if not if(~ $"cgi_bin /*){
	cgi_dir=`{basename -d $"cgi_bin}
	cgi_dir=$"cgi_dir
}
if(! ~ $"cgi_bin */*)
	cgi_bin=./$"cgi_bin
if(! builtin cd $"cgi_dir >[2]/dev/null || ! test -x $"cgi_bin){
	error 500
	exit
}

run_cgi | {
	filter_headers
	emit_extra_headers
	echo $cr
	exec cat
}