shithub: mc

ref: 72958419b4fb70531051e05e2ca56ecccc524b6b
dir: /lib/std/dial+plan9.myr/

use sys

use "alloc"
use "die"
use "fmt"
use "option"
use "pathjoin"
use "result"
use "sleq"
use "strfind"
use "strstrip"
use "syswrap"
use "utf"


pkg std =
	const dial	: (dialstr : byte[:] -> result(fd, byte[:]))
;;

const Maxpath = 512

const dial = {str
	var netdir, proto, rem

	(netdir, proto, rem) = parsedial(str)
	if netdir.len != 0
		-> csdial(netdir, proto, rem)
	;;

	match csdial("/net", proto, rem)
	| `Ok fd:	-> `Ok fd
	| `Err m:
		-> csdial("/net.alt", proto, rem)
	;;
}

const csdial = {netdir, proto, rem
	var dir, clone, addr, csaddr
	var ret, csfd, n
	var buf	: byte[Maxpath]

	/* Try using the connection server */
	dir = fmt("{}/cs", netdir)
	match open(dir, Ordwr)
	| `Err e:
		clone = fmt("{}/{}/clone", netdir, proto)
		match call(clone, rem, netdir)
		| `Ok fd:
			std.slfree(clone)
			-> `Ok fd
		| `Err err:
			std.slfree(clone)
			-> `Err "unable to dial without cs"
		;;
	| `Ok fd:
		csfd = fd
	;;
	slfree(dir)

	csaddr = fmt("{}!{}", proto, rem)
	match write(csfd, csaddr)
	| `Err m:
		close(csfd)
		-> `Err "couldn't blah cs"
	| `Ok _:
		/* nothing */
	;;
	slfree(csaddr)

	seek(csfd, 0, 0)
	while true
		match read(csfd, buf[:])
		| `std.Ok len:	n = len
		| `std.Err e:	break
		;;

		match strfind(buf[:n], " ")
		| `None:	continue
		| `Some i:
			clone = buf[:i]
			addr = buf[i+1:n]
		;;

		match call(clone, addr, netdir)
		| `Ok fd:	break
		| `Err _:	/* nothing */
		;;
	;;

	close(csfd)
	if ret < 0
		-> `Err "unable to dial"
	;;
	-> `Ok ret
}

const call : (a : byte[:], b : byte[:], c : byte[:] -> result(fd, byte[:])) = {clone, addr, netdir
	var namebuf : byte[Maxpath]
	var databuf : byte[Maxpath]
	var name, base, dpath
	var cfd, datafd
	var c, n

	datafd = `Err "didn't even try to open shit"
	c = nsclonestr(clone, netdir)
	match open(c, Ordwr)
	| `Err e:	goto cleanup
	| `Ok fd:	cfd = fd
	;;

	match read(cfd, namebuf[:])
	| `Ok len:	n = len
	| `Err m:	goto cleanup
	;;

	name = strstrip(namebuf[:n])
	match strrfind(c, "/")
	| `None:	die("there should be a '/' here\n")
	| `Some i:	base = c[:i]
	;;

	dpath = bfmt(databuf[:], "{}/{}/data", base, name)
	match open(dpath, Ordwr)
	| `Ok fd:	datafd = `Ok fd
	| `Err m:	datafd = `Err "could not open data"
	;;

:cleanup
	close(cfd)
	slfree(c)
	-> datafd
}

const nsclonestr = {clone, netdir
	if decode(clone) == '#' || decode(clone) == '/'
		match std.strfind(clone[1:], "/")
		| `Some i:	clone = clone[i+1:]
		| `None:	/* nothing */
		;;
	;;
	-> pathcat(netdir, clone)
}

const parsedial = {str
	var netdir, proto, rem, hd, tl

	netdir=""
	proto = ""
	rem = ""
	match strfind(str, "!")
	| `None:
		proto = "net"
		rem = str
	| `Some sep:
		hd = str[:sep]
		tl = str[sep+1:]
		if decode(hd) == '#' || decode(hd) == '/'
			match strrfind(hd, "/")
			| `Some idx:
				netdir = hd[:idx]
				proto = hd[idx+1:]
			| `None:
				netdir = ""
				proto = hd
			;;
		else
			netdir = ""
			proto = hd

		;;
		rem = tl
	;;

	-> (netdir, proto, rem)
}