plan9fox/rc/bin/hget

#!/bin/rc
rfork e
argv0=$0
fn usage {
	echo usage: $argv0 [ -o file ] [ -p body ] [ -r header ] [ -m method ] [ -b baseurl ] url >[1=2]
	exit usage
}
s=0
o=()
p=()
r=()
m=()
b=()
while(~ $1 -*){
	switch($1){
	case -o
		o=$2
		shift
	case -p
		p=$2
		shift
	case -r
		r=($r $2)
		shift
	case -m
		m=$2
		shift
	case -b
		b=$2
		shift
	case *
		usage
	}
	shift
}
if(! ~ $#* 1)
	usage
if(! ~ $#o 0){
	if(! ~ $#o 1)
		usage
	if(test -s $o)
		s=`{ls -l $o | awk '{print $6}'}
}
if(! ~ $s 0)
	r=($r 'Range: bytes='^$s^'-')
<>/mnt/web/clone {
	d=/mnt/web/^`{sed 1q}
	if(~ $#b 1)
		echo -n baseurl $b >[1=0]
	echo -n url $1 >[1=0]
	for(i in $r)
		echo -n headers $i >[1=0]
	if(~ $#m 1)
		echo -n request $m >[1=0]
	if(! ~ $#p 0)
		echo -n $"p >$d/postbody
	<$d/body {
		if(~ $#o 1){
			l=`{cat $d/contentlength >[2]/dev/null}
			x=`{awk 'BEGIN{FS=" |-"}/^bytes ([0-9]+)\-/{print $2}' \
				$d/contentrange >[2]/dev/null}
			if(~ $s $l && ~ $#x 0)
				exit
			if(~ $s $x)
				exec cat >>$o
			exec cat >$o
		}
		exec cat
	}
}