1 2bc5ec6b 2023-12-19 op // This is free and unencumbered software released into the public domain.
  2 2bc5ec6b 2023-12-19 op //
  3 2bc5ec6b 2023-12-19 op // Anyone is free to copy, modify, publish, use, compile, sell, or
  4 2bc5ec6b 2023-12-19 op // distribute this software, either in source code form or as a compiled
  5 2bc5ec6b 2023-12-19 op // binary, for any purpose, commercial or non-commercial, and by any
  6 2bc5ec6b 2023-12-19 op // means.
  7 2bc5ec6b 2023-12-19 op //
  8 2bc5ec6b 2023-12-19 op // In jurisdictions that recognize copyright laws, the author or authors
  9 2bc5ec6b 2023-12-19 op // of this software dedicate any and all copyright interest in the
 10 2bc5ec6b 2023-12-19 op // software to the public domain. We make this dedication for the benefit
 11 2bc5ec6b 2023-12-19 op // of the public at large and to the detriment of our heirs and
 12 2bc5ec6b 2023-12-19 op // successors. We intend this dedication to be an overt act of
 13 2bc5ec6b 2023-12-19 op // relinquishment in perpetuity of all present and future rights to this
 14 2bc5ec6b 2023-12-19 op // software under copyright law.
 15 2bc5ec6b 2023-12-19 op //
 16 2bc5ec6b 2023-12-19 op // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 17 2bc5ec6b 2023-12-19 op // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 18 2bc5ec6b 2023-12-19 op // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 19 2bc5ec6b 2023-12-19 op // IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 20 2bc5ec6b 2023-12-19 op // OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 21 2bc5ec6b 2023-12-19 op // ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 22 2bc5ec6b 2023-12-19 op // OTHER DEALINGS IN THE SOFTWARE.
 23 2bc5ec6b 2023-12-19 op 
 24 2bc5ec6b 2023-12-19 op // XXX would be nice to eventually have multiple backends for poll,
 25 2bc5ec6b 2023-12-19 op // kqueue, epoll.
 26 2bc5ec6b 2023-12-19 op 
 27 2bc5ec6b 2023-12-19 op use errors;
 28 2bc5ec6b 2023-12-19 op use io;
 29 2bc5ec6b 2023-12-19 op use unix;
 30 2bc5ec6b 2023-12-19 op use unix::poll;
 31 2bc5ec6b 2023-12-19 op use unix::signal;
 32 2bc5ec6b 2023-12-19 op 
 33 2bc5ec6b 2023-12-19 op export type event = enum i16 {
 34 2bc5ec6b 2023-12-19 op 	READ,
 35 2bc5ec6b 2023-12-19 op 	WRITE,
 36 2bc5ec6b 2023-12-19 op };
 37 2bc5ec6b 2023-12-19 op 
 38 f2f593e9 2023-12-19 op export def READ = event::READ;
 39 f2f593e9 2023-12-19 op export def WRITE = event::WRITE;
 40 2bc5ec6b 2023-12-19 op 
 41 2bc5ec6b 2023-12-19 op type cb = struct {
 42 01312690 2023-12-19 op 	cb: *fn(io::file, event, nullable *opaque) void,
 43 01312690 2023-12-19 op 	data: nullable *opaque,
 44 2bc5ec6b 2023-12-19 op };
 45 2bc5ec6b 2023-12-19 op 
 46 e9feffee 2023-12-19 op type queue = struct {
 47 2bc5ec6b 2023-12-19 op 	pfds: []poll::pollfd,
 48 2bc5ec6b 2023-12-19 op 	cbs: []cb,
 49 e9feffee 2023-12-19 op };
 50 e9feffee 2023-12-19 op 
 51 e9feffee 2023-12-19 op type base = struct {
 52 e9feffee 2023-12-19 op 	working: queue,
 53 e9feffee 2023-12-19 op 	wip: queue,
 54 2bc5ec6b 2023-12-19 op 	sigpipe: ((io::file, io::file) | void),
 55 2bc5ec6b 2023-12-19 op 	sigcb: (cb | void),
 56 2bc5ec6b 2023-12-19 op 	stop: bool, // signal to stop
 57 2bc5ec6b 2023-12-19 op 	// TODO: timeout
 58 2bc5ec6b 2023-12-19 op };
 59 2bc5ec6b 2023-12-19 op 
 60 2bc5ec6b 2023-12-19 op let b = base {
 61 2bc5ec6b 2023-12-19 op 	sigpipe = void,
 62 2bc5ec6b 2023-12-19 op 	sigcb = void,
 63 2bc5ec6b 2023-12-19 op 	...
 64 2bc5ec6b 2023-12-19 op };
 65 2bc5ec6b 2023-12-19 op 
 66 2bc5ec6b 2023-12-19 op fn ev2poll(ev: event) poll::event = switch (ev) {
 67 2bc5ec6b 2023-12-19 op 	case event::READ => yield poll::event::POLLIN;
 68 2bc5ec6b 2023-12-19 op 	case event::WRITE => yield poll::event::POLLOUT;
 69 2bc5ec6b 2023-12-19 op };
 70 2bc5ec6b 2023-12-19 op 
 71 2bc5ec6b 2023-12-19 op fn poll2ev(ev: i16) event = {
 72 2bc5ec6b 2023-12-19 op 	if ((ev & poll::event::POLLOUT) != 0) {
 73 2bc5ec6b 2023-12-19 op 		return event::WRITE;
 74 2bc5ec6b 2023-12-19 op 	};
 75 2bc5ec6b 2023-12-19 op 	return event::READ;
 76 2bc5ec6b 2023-12-19 op };
 77 2bc5ec6b 2023-12-19 op 
 78 01312690 2023-12-19 op export fn add(fd: io::file, ev: event, f: *fn(io::file, event, nullable *opaque) void, data: nullable *opaque) void = {
 79 e9feffee 2023-12-19 op 	append(b.wip.pfds, poll::pollfd {
 80 2bc5ec6b 2023-12-19 op 		fd = fd,
 81 2bc5ec6b 2023-12-19 op 		events = ev2poll(ev),
 82 2bc5ec6b 2023-12-19 op 		...
 83 2bc5ec6b 2023-12-19 op 	});
 84 e9feffee 2023-12-19 op 	append(b.wip.cbs, cb {
 85 2bc5ec6b 2023-12-19 op 		cb = f,
 86 2bc5ec6b 2023-12-19 op 		data = data,
 87 2bc5ec6b 2023-12-19 op 	});
 88 2bc5ec6b 2023-12-19 op };
 89 2bc5ec6b 2023-12-19 op 
 90 2bc5ec6b 2023-12-19 op export fn del(fd: io::file) void = {
 91 e9feffee 2023-12-19 op 	for (let i = 0z; i < len(b.wip.pfds); i += 1) {
 92 e9feffee 2023-12-19 op 		if (b.wip.pfds[i].fd != fd) {
 93 2bc5ec6b 2023-12-19 op 			continue;
 94 2bc5ec6b 2023-12-19 op 		};
 95 e9feffee 2023-12-19 op 		delete(b.wip.pfds[i]);
 96 e9feffee 2023-12-19 op 		delete(b.wip.cbs[i]);
 97 2bc5ec6b 2023-12-19 op 		return;
 98 2bc5ec6b 2023-12-19 op 	};
 99 2bc5ec6b 2023-12-19 op };
100 2bc5ec6b 2023-12-19 op 
101 e9feffee 2023-12-19 op fn prepare_queue() void = {
102 e9feffee 2023-12-19 op 	let wip = b.wip;
103 e9feffee 2023-12-19 op 
104 e9feffee 2023-12-19 op 	if (len(b.working.pfds) > 0) {
105 e9feffee 2023-12-19 op 		delete(b.working.pfds[..]);
106 e9feffee 2023-12-19 op 		delete(b.working.cbs[..]);
107 e9feffee 2023-12-19 op 	};
108 e9feffee 2023-12-19 op 
109 e9feffee 2023-12-19 op 	for (let i = 0z; i < len(wip.pfds); i += 1) {
110 e9feffee 2023-12-19 op 		append(b.working.pfds, wip.pfds[i]);
111 e9feffee 2023-12-19 op 		append(b.working.cbs, wip.cbs[i]);
112 e9feffee 2023-12-19 op 	};
113 e9feffee 2023-12-19 op };
114 e9feffee 2023-12-19 op 
115 2bc5ec6b 2023-12-19 op export fn loop() (void | poll::error) = {
116 2bc5ec6b 2023-12-19 op 	const mask = poll::event::POLLIN | poll::event::POLLOUT |
117 2bc5ec6b 2023-12-19 op 		poll::event::POLLHUP;
118 2bc5ec6b 2023-12-19 op 
119 2bc5ec6b 2023-12-19 op 	for (!b.stop) {
120 e9feffee 2023-12-19 op 		prepare_queue();
121 e9feffee 2023-12-19 op 
122 e9feffee 2023-12-19 op 		let q = b.working;
123 e9feffee 2023-12-19 op 
124 e9feffee 2023-12-19 op 		let n = poll::poll(q.pfds, poll::INDEF)?;
125 e9feffee 2023-12-19 op 		for (let i = 0z; i < len(q.pfds); i += 1) {
126 e9feffee 2023-12-19 op 			if ((q.pfds[i].revents & mask) == 0) {
127 2bc5ec6b 2023-12-19 op 				continue;
128 2bc5ec6b 2023-12-19 op 			};
129 e9feffee 2023-12-19 op 			q.cbs[i].cb(q.pfds[i].fd, poll2ev(q.pfds[i].revents),
130 e9feffee 2023-12-19 op 				q.cbs[i].data);
131 2bc5ec6b 2023-12-19 op 		};
132 2bc5ec6b 2023-12-19 op 	};
133 2bc5ec6b 2023-12-19 op };
134 2bc5ec6b 2023-12-19 op 
135 2bc5ec6b 2023-12-19 op export fn loopexit() void = {
136 2bc5ec6b 2023-12-19 op 	b.stop = true;
137 2bc5ec6b 2023-12-19 op };