pty.ha (1930B)
1 // SPDX-License-Identifier: MPL-2.0 2 // (c) Hare authors <https://harelang.org> 3 4 use errors; 5 use fs; 6 use io; 7 use os; 8 use rt; 9 use types::c; 10 use strings; 11 12 // Opens an available pseudoterminal and returns the file descriptors of the 13 // master and slave. 14 export fn openpty() ((io::file, io::file) | fs::error) = { 15 let master = open_master()?; 16 let slave = match (get_slave(master)) { 17 case let e: fs::error => 18 io::close(master)!; 19 return e; 20 case let s: io::file => 21 yield s; 22 }; 23 return (master, slave); 24 }; 25 26 // Opens an available pseudoterminal master. 27 fn open_master() (io::file | fs::error) = { 28 match (rt::posix_openpt(rt::O_RDWR | rt::O_NOCTTY)) { 29 case let e: rt::errno => 30 return errors::errno(e); 31 case let i: int => 32 return io::fdopen(i); 33 }; 34 }; 35 36 // Returns a file descriptor referring to the pseudoterminal slave for a 37 // pseudoterminal master. 38 fn get_slave(master: io::file) (io::file | fs::error) = 39 os::open(ptsname(master)?, fs::flag::RDWR); 40 41 // Returns the filename of the pseudoterminal slave. 42 export fn ptsname(master: io::file) (str | error) = { 43 let pm = rt::ptmget { ... }; 44 match (rt::ioctl(master, rt::TIOCPTSNAME, &pm)) { 45 case let e: rt::errno => 46 switch (e) { 47 case rt::EBADF => 48 return errors::invalid; 49 case rt::EINVAL, rt::ENOTTY => 50 return errors::unsupported; 51 case => 52 abort("Unexpected error from ioctl"); 53 }; 54 case => void; 55 }; 56 return strings::dup(c::tostr(&pm.sn: *const c::char)!); 57 }; 58 59 // Sets the dimensions of the underlying pseudoterminal for an [[io::file]]. 60 export fn set_winsize(pty: io::file, sz: ttysize) (void | error) = { 61 let wsz = rt::winsize { ws_row = sz.rows, ws_col = sz.columns, ... }; 62 match (rt::ioctl(pty, rt::TIOCSWINSZ, &wsz)) { 63 case let e: rt::errno => 64 switch (e) { 65 case rt::EBADF, rt::EINVAL => 66 return errors::invalid; 67 case rt::ENOTTY => 68 return errors::unsupported; 69 case => 70 abort("Unexpected error from ioctl"); 71 }; 72 case => void; 73 }; 74 };