zig-riscv-embedded

 1// Copyright © 2021 Sören Tempel
 2//
 3// This program is free software: you can redistribute it and/or modify
 4// it under the terms of the GNU Affero General Public License as
 5// published by the Free Software Foundation, either version 3 of the
 6// License, or (at your option) any later version.
 7//
 8// This program is distributed in the hope that it will be useful, but
 9// WITHOUT ANY WARRANTY; without even the implied warranty of
10// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11// Affero General Public License for more details.
12//
13// You should have received a copy of the GNU Affero General Public License
14// along with this program. If not, see <https://www.gnu.org/licenses/>.
15
16const console = @import("console.zig");
17const slipmux = @import("slipmux.zig");
18const periph = @import("periph.zig");
19const zoap = @import("zoap");
20const codes = zoap.codes;
21
22const resources = &[_]zoap.Resource{
23    .{ .path = "about", .handler = about },
24    .{ .path = "on", .handler = ledOn },
25    .{ .path = "off", .handler = ledOff },
26};
27var dispatcher = zoap.Dispatcher{
28    .resources = resources,
29};
30
31pub fn about(resp: *zoap.Response, req: *zoap.Request) codes.Code {
32    if (!req.header.code.equal(codes.GET))
33        return codes.BAD_METHOD;
34
35    console.print("[coap] Received /about request\n", .{});
36
37    const w = resp.payloadWriter();
38    w.writeAll("zig-riscv-embedded licensed under AGPL3+") catch |err| {
39        console.print("[coap] error in /about: {s}\n", .{@errorName(err)});
40        return codes.INTERNAL_ERR;
41    };
42
43    return codes.CONTENT;
44}
45
46pub fn ledOn(resp: *zoap.Response, req: *zoap.Request) codes.Code {
47    _ = resp; // Don't change response abort from code
48
49    if (!req.header.code.equal(codes.PUT))
50        return codes.BAD_METHOD;
51
52    console.print("[coap] Turning LED on\n", .{});
53    periph.gpio0.set(periph.led0, 0);
54
55    return codes.CHANGED;
56}
57
58pub fn ledOff(resp: *zoap.Response, req: *zoap.Request) codes.Code {
59    _ = resp; // Don't change response abort from code
60
61    if (!req.header.code.equal(codes.PUT))
62        return codes.BAD_METHOD;
63
64    console.print("[coap] Turning LED off\n", .{});
65    periph.gpio0.set(periph.led0, 1);
66
67    return codes.CHANGED;
68}
69
70pub fn coapHandler(req: *zoap.Request) void {
71    console.print("[coap] Incoming request\n", .{});
72    var resp = dispatcher.dispatch(req) catch |err| {
73        console.print("[coap] Dispatch failed: {s}\n", .{@errorName(err)});
74        return;
75    };
76
77    const ftype = slipmux.FrameType.coap;
78    var frame = periph.slipmux.newFrame(ftype);
79
80    try frame.writer().writeAll(resp.marshal());
81    frame.close();
82}
83
84pub fn main() !void {
85    try periph.slipmux.registerHandler(coapHandler);
86    console.print("Waiting for incoming CoAP packets over UART0...\n", .{});
87}