shithub: mc

ref: 420aa87291660b3452f42d637227b157dbf86846
dir: /lib/bio/fd.myr/

View raw version
use std

use "bio"
use "types"

pkg bio =
	const mkfile	: (fd : std.fd, mode : mode	-> file#)
	const open	: (path : byte[:], mode : mode	-> std.result(file#, byte[:]))
	const dial	: (srv	: byte[:], mode : mode	-> std.result(file#, byte[:]))
	const create	: (path : byte[:], mode : mode, perm : int	-> std.result(file#, byte[:]))
;;

const mkfile = {fd, mode
	-> mk(mode, [
		.read	= {buf;	-> std.read(fd, buf)},
		.write	= {buf;	-> std.write(fd, buf)},
		.seek	= {off;	-> std.seek(fd, off, std.Seekset)},
		.close	= {;	-> std.close(fd) >= 0},
	])
}

/* Opens a file with mode provided. */
const open = {path, mode 
	-> sysopen(path, mode, sysmode(mode), 0o777)
}

/*
   Creates a file for the provided path, with opened in
   the requested mode, with the requested permissions
*/
const create = {path, mode, perm
	-> sysopen(path, mode, sysmode(mode) | std.Ocreat | std.Otrunc, perm)
}

/* dial the server, and open a file using the returned fd */
const dial = {srv, mode
	match std.dial(srv)
	| `std.Ok sock:	-> `std.Ok mkfile(sock, mode)
	| `std.Err m:	-> `std.Err m
	;;
}

/* map from the bio modes to the unix open modes */
const sysmode = {mode
	match mode
	| Rd:	-> std.Oread
	| Wr:	-> std.Owrite
	| Rw:	-> std.Ordwr
	| _:	std.fatal("bio: bad file mode")
	;;
	-> 0
}

/* open the file, and return it */
const sysopen = {path, mode, openmode, perm
	match std.openmode(path, openmode, (perm : int64))
	| `std.Ok fd:	-> `std.Ok mkfile(fd, mode)
	| `std.Err e:	-> `std.Err "could not open fd"
	;;
}