shithub: mc

ref: 22d71e9e0471402b4d9e918f4f10683137ee9121
dir: /lib/http/parse.myr/

use std
use bio

use "types"

pkg http =
	pkglocal const parseresp	: (s : session#, r : resp# -> bool)
	pkglocal const parsechunksz	: (s : session# -> std.result(std.size, err))
	pkglocal const parsenumber	: (str : byte[:]#, base : int -> std.option(int))
;;

const parseresp = {s, r
	match bio.readln(s.f)
	| `bio.Err e:	r.err = `std.Some `Econn
	| `bio.Eof:	r.err = `std.Some `Econn
	| `bio.Ok ln:
		if !parsestatus(s, r, ln)
			std.slfree(ln)
			-> false
		;;
		std.slfree(ln)
	;;

	while true
		match bio.readln(s.f)
		| `bio.Err e:	r.err = `std.Some `Econn
		| `bio.Eof:	r.err = `std.Some `Econn
		| `bio.Ok ln:
			if std.strstrip(ln).len == 0
				break
			;;
			if !parsehdr(s, r, ln)
				std.slfree(ln)
				-> false
			;;
			std.slfree(ln)
		;;
	;;

	match getenc(r)
	| `std.Ok `Length:
		r.enc = `Length
		match getlen(r)
		| `std.Some n:
			r.len = n
		| `std.None:
			r.err = `std.Some `Eproto
			-> false
		;;
	| `std.Ok enc:
		r.enc = enc
	| `std.Fail e:
		r.err = `std.Some e
		-> false
	;;
	-> true

}

const parsechunksz = {s
	var ret, str

	match bio.readln(s.f)
	| `bio.Eof:	ret = `std.Fail `Econn
	| `bio.Err e:	ret = `std.Fail `Econn
	| `bio.Ok ln:
		str = ln
		match parsenumber(&str, 16)
		| `std.Some n:	ret = `std.Ok (n : std.size)
		| `std.None:
			ret = `std.Fail `Eproto
		;;
		std.slfree(ln)
	;;
	-> ret
}

const parsestatus = {s, r, ln
	/* HTTP/1.1 */
	ln = std.strfstrip(ln)
	if !std.chomp(&ln, "HTTP")
		r.err = `std.Some `Eproto
		-> false
	;;
	if !std.chomp(&ln, "/1.1")
		r.err = `std.Some `Eproto
		-> false
	;;

	ln = std.strfstrip(ln)
	match parsenumber(&ln, 10)
	| `std.Some n:
		r.status = n
	| `std.None:
		r.err = `std.Some `Eproto
		-> false
	;;

	ln = std.strfstrip(ln)
	r.reason = std.sldup(ln)
	-> true
}

const parsehdr = {s, r, ln
	var key, val

	match std.strfind(ln, ":")
	| `std.Some idx:
		key = std.sldup(std.strstrip(ln[:idx]))
		val = std.sldup(std.strstrip(ln[idx+1:]))
		std.slpush(&r.hdrs, (key, val))
		-> true
	| `std.None:
		r.err = `std.Some `Ehdr
		-> false
	;;
}

const getlen = {r
	match findhdr(r, "Content-Length")
	| `std.Some v:
		match std.intparsebase(v, 10)
		| `std.Some n:	-> `std.Some n
		| `std.None:	-> `std.None
		;;
	| `std.None:
		-> `std.None
	;;
}

const getenc = {r
	match findhdr(r, "Transfer-Encoding")
	| `std.None:	-> `std.Ok `Length
	| `std.Some "chunked":	-> `std.Ok `Chunked
	| `std.Some "compress":	-> `std.Ok `Compress
	| `std.Some "deflate":	-> `std.Ok `Deflate
	| `std.Some "gzip":	-> `std.Ok `Gzip
	| `std.Some unknown:	-> `std.Fail `Eenc
	;;
}

const findhdr = {r, name
	for (k, v) in r.hdrs
		if std.strcaseeq(k, name)
			-> `std.Some v
		;;
	;;
	-> `std.None
}

const parsenumber = {ln, base
	var n, ok
	var c, s, dig

	n = 0
	s = ln#
	ok = false
	while true
		(c, s) = std.strstep(s)
		dig = std.charval(c, base)
		if dig >= 0 && dig < base
			ok = true
			n *= base
			n += dig
		else
			break
		;;
	;;
	ln# = s
	if ok
		-> `std.Some n
	else
		-> `std.None
	;;
}