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Add receiving UDP impl

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This commit is contained in:
Muaz Ahmad 2024-05-11 17:40:56 +05:00
parent 5b03128c39
commit 98264d26e1
1 changed files with 31 additions and 17 deletions
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48
src/mdns.zig
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@ -6,6 +6,7 @@ const MDNSError = error{
SocketInitFail,
UDPConnectFail,
UDPSendFail,
UDPRecvFail,
};
pub fn get_mdns(domain: util.Domain, ip_info: util.IPInfo) !util.IPs {
@ -14,19 +15,9 @@ pub fn get_mdns(domain: util.Domain, ip_info: util.IPInfo) !util.IPs {
}
const socket = c_int;
const MSG_BUFF_SIZE = 200;
fn get_mdns_socket(ip_info: util.IPInfo) !socket {
const target_addr: []const u8 = switch (ip_info.version) {
util.IP_VER_ENUM.IPv4 => "224.0.0.251",
util.IP_VER_ENUM.IPv6 => blk: {
var buf = [_]u8{0x00} ** 100;
var byte_buf = std.io.fixedBufferStream(&buf);
const writer = byte_buf.writer();
try std.fmt.format(writer, "ff02::fb%{s}", .{ip_info.interface.?});
break :blk buf[0..writer.context.pos];
},
};
const addr = try std.net.Address.resolveIp(target_addr, 5353);
const sock = std.c.socket(switch (ip_info.version) {
util.IP_VER_ENUM.IPv4 => std.c.AF.INET,
util.IP_VER_ENUM.IPv6 => std.c.AF.INET6,
@ -34,9 +25,6 @@ fn get_mdns_socket(ip_info: util.IPInfo) !socket {
if (sock == -1) {
return MDNSError.SocketInitFail;
}
if (std.c.connect(sock, &addr.any, addr.getOsSockLen()) == -1) {
return MDNSError.UDPConnectFail;
}
return sock;
}
@ -74,17 +62,43 @@ fn construct_mdns_query(domain: util.Domain, ip_info: util.IPInfo, buff: []u8) !
fn send_query(domain: util.Domain, ip_info: util.IPInfo) !socket {
const sock = try get_mdns_socket(ip_info);
errdefer _ = std.c.close(sock);
var buff = [_]u8{0x00} ** 100;
const target_addr: []const u8 = switch (ip_info.version) {
util.IP_VER_ENUM.IPv4 => "224.0.0.251",
util.IP_VER_ENUM.IPv6 => blk: {
var buf = [_]u8{0x00} ** MSG_BUFF_SIZE;
var byte_buf = std.io.fixedBufferStream(&buf);
const writer = byte_buf.writer();
try std.fmt.format(writer, "ff02::fb%{s}", .{ip_info.interface.?});
break :blk buf[0..writer.context.pos];
},
};
const addr = try std.net.Address.resolveIp(target_addr, 5353);
var buff = [_]u8{0x00} ** MSG_BUFF_SIZE;
const n = try construct_mdns_query(domain, ip_info, &buff);
if (std.c.send(sock, &buff, n, 0) == -1) {
if (std.c.sendto(sock, &buff, n, 0, &addr.any, addr.getOsSockLen()) == -1) {
return MDNSError.UDPSendFail;
}
return sock;
}
fn receive_query(sock: socket) !util.IPs {
_ = sock;
defer _ = std.c.close(sock);
var buff = [_]u8{0x00} ** MSG_BUFF_SIZE;
const n: usize = blk: {
const ret = std.c.recv(sock, &buff, MSG_BUFF_SIZE, 0);
if (ret < 0) {
return MDNSError.UDPRecvFail;
} else {
break :blk @bitCast(ret);
}
};
std.debug.print("{any}\n", .{buff[0..n]});
return util.IPs{
.v4 = "",
.v6 = "",