std.Io.net.HostName: finish implementing DNS lookup

This commit is contained in:
Andrew Kelley 2025-09-29 23:27:00 -07:00
parent 2e1ab5d3f7
commit b22400271f
4 changed files with 237 additions and 148 deletions

View file

@ -641,8 +641,8 @@ pub const VTable = struct {
context_alignment: std.mem.Alignment,
start: *const fn (context: *const anyopaque) void,
) void,
groupWait: *const fn (?*anyopaque, *Group) void,
groupCancel: *const fn (?*anyopaque, *Group) void,
groupWait: *const fn (?*anyopaque, *Group, token: *anyopaque) void,
groupCancel: *const fn (?*anyopaque, *Group, token: *anyopaque) void,
/// Blocks until one of the futures from the list has a result ready, such
/// that awaiting it will not block. Returns that index.
@ -665,14 +665,14 @@ pub const VTable = struct {
fileSeekBy: *const fn (?*anyopaque, file: File, offset: i64) File.SeekError!void,
fileSeekTo: *const fn (?*anyopaque, file: File, offset: u64) File.SeekError!void,
now: *const fn (?*anyopaque, clockid: std.posix.clockid_t) ClockGetTimeError!Timestamp,
sleep: *const fn (?*anyopaque, clockid: std.posix.clockid_t, deadline: Deadline) SleepError!void,
now: *const fn (?*anyopaque, clockid: std.posix.clockid_t) NowError!Timestamp,
sleep: *const fn (?*anyopaque, clockid: std.posix.clockid_t, timeout: Timeout) SleepError!void,
listen: *const fn (?*anyopaque, address: net.IpAddress, options: net.IpAddress.ListenOptions) net.IpAddress.ListenError!net.Server,
accept: *const fn (?*anyopaque, server: *net.Server) net.Server.AcceptError!net.Stream,
ipBind: *const fn (?*anyopaque, address: net.IpAddress, options: net.IpAddress.BindOptions) net.IpAddress.BindError!net.Socket,
netSend: *const fn (?*anyopaque, handle: net.Socket.Handle, address: net.IpAddress, data: []const u8) net.Socket.SendError!void,
netReceive: *const fn (?*anyopaque, handle: net.Socket.Handle, address: net.IpAddress, buffer: []u8) net.Socket.ReceiveError!void,
netSend: *const fn (?*anyopaque, handle: net.Socket.Handle, address: *const net.IpAddress, data: []const u8) net.Socket.SendError!void,
netReceive: *const fn (?*anyopaque, handle: net.Socket.Handle, buffer: []u8, timeout: Timeout) net.Socket.ReceiveTimeoutError!net.ReceivedMessage,
netRead: *const fn (?*anyopaque, src: net.Stream, data: [][]u8) net.Stream.Reader.Error!usize,
netWrite: *const fn (?*anyopaque, dest: net.Stream, header: []const u8, data: []const []const u8, splat: usize) net.Stream.Writer.Error!usize,
netClose: *const fn (?*anyopaque, handle: net.Socket.Handle) void,
@ -710,6 +710,15 @@ pub const Timestamp = enum(i96) {
pub fn addDuration(from: Timestamp, duration: Duration) Timestamp {
return @enumFromInt(@intFromEnum(from) + duration.nanoseconds);
}
pub fn fromNow(io: Io, clockid: std.posix.clockid_t, duration: Duration) NowError!Timestamp {
const now_ts = try now(io, clockid);
return addDuration(now_ts, duration);
}
pub fn compare(lhs: Timestamp, op: std.math.CompareOperator, rhs: Timestamp) bool {
return std.math.compare(@intFromEnum(lhs), op, @intFromEnum(rhs));
}
};
pub const Duration = struct {
nanoseconds: i96,
@ -722,11 +731,14 @@ pub const Duration = struct {
return .{ .nanoseconds = @as(i96, x) * std.time.ns_per_s };
}
};
pub const Deadline = union(enum) {
pub const Timeout = union(enum) {
none,
duration: Duration,
timestamp: Timestamp,
deadline: Timestamp,
pub const Error = error{Timeout};
};
pub const ClockGetTimeError = std.posix.ClockGetTimeError || Cancelable;
pub const NowError = std.posix.ClockGetTimeError || Cancelable;
pub const SleepError = error{ UnsupportedClock, Unexpected, Canceled };
pub const AnyFuture = opaque {};
@ -768,8 +780,10 @@ pub const Group = struct {
///
/// `function` *may* be called immediately, before `async` returns.
///
/// After this is called, `wait` must be called before the group is
/// deinitialized.
/// After this is called, `wait` or `cancel` must be called before the
/// group is deinitialized.
///
/// Threadsafe.
///
/// See also:
/// * `Io.async`
@ -789,7 +803,9 @@ pub const Group = struct {
///
/// Idempotent. Not threadsafe.
pub fn wait(g: *Group, io: Io) void {
io.vtable.groupWait(io.userdata, g);
const token = g.token orelse return;
g.token = null;
io.vtable.groupWait(io.userdata, g, token);
}
/// Equivalent to `wait` but requests cancellation on all tasks owned by
@ -797,9 +813,9 @@ pub const Group = struct {
///
/// Idempotent. Not threadsafe.
pub fn cancel(g: *Group, io: Io) void {
if (g.token == null) return;
io.vtable.groupCancel(io.userdata, g);
assert(g.token == null);
const token = g.token orelse return;
g.token = null;
io.vtable.groupCancel(io.userdata, g, token);
}
};
@ -1215,12 +1231,12 @@ pub fn cancelRequested(io: Io) bool {
return io.vtable.cancelRequested(io.userdata);
}
pub fn now(io: Io, clockid: std.posix.clockid_t) ClockGetTimeError!Timestamp {
pub fn now(io: Io, clockid: std.posix.clockid_t) NowError!Timestamp {
return io.vtable.now(io.userdata, clockid);
}
pub fn sleep(io: Io, clockid: std.posix.clockid_t, deadline: Deadline) SleepError!void {
return io.vtable.sleep(io.userdata, clockid, deadline);
pub fn sleep(io: Io, clockid: std.posix.clockid_t, timeout: Timeout) SleepError!void {
return io.vtable.sleep(io.userdata, clockid, timeout);
}
pub fn sleepDuration(io: Io, duration: Duration) SleepError!void {

View file

@ -463,16 +463,19 @@ fn groupAsync(
},
.pool = pool,
.group = group,
.node = .{ .next = @ptrCast(@alignCast(group.token)) },
.node = undefined,
.func = start,
.context_alignment = context_alignment,
.context_len = context.len,
};
group.token = &gc.node;
@memcpy(gc.contextPointer()[0..context.len], context);
pool.mutex.lock();
// Append to the group linked list inside the mutex to make `Io.Group.async` thread-safe.
gc.node = .{ .next = @ptrCast(@alignCast(group.token)) };
group.token = &gc.node;
const thread_capacity = cpu_count - 1 + pool.concurrent_count;
pool.threads.ensureTotalCapacityPrecise(gpa, thread_capacity) catch {
@ -493,6 +496,8 @@ fn groupAsync(
pool.threads.appendAssumeCapacity(thread);
}
// This needs to be done before unlocking the mutex to avoid a race with
// the associated task finishing.
const group_state: *std.atomic.Value(usize) = @ptrCast(&group.state);
std.Thread.WaitGroup.startStateless(group_state);
@ -500,21 +505,16 @@ fn groupAsync(
pool.cond.signal();
}
fn groupWait(userdata: ?*anyopaque, group: *Io.Group) void {
if (builtin.single_threaded) return;
fn groupWait(userdata: ?*anyopaque, group: *Io.Group, token: *anyopaque) void {
const pool: *Pool = @ptrCast(@alignCast(userdata));
_ = pool;
if (builtin.single_threaded) return;
const group_state: *std.atomic.Value(usize) = @ptrCast(&group.state);
const reset_event: *ResetEvent = @ptrCast(&group.context);
std.Thread.WaitGroup.waitStateless(group_state, reset_event);
}
fn groupCancel(userdata: ?*anyopaque, group: *Io.Group) void {
if (builtin.single_threaded) return;
const pool: *Pool = @ptrCast(@alignCast(userdata));
_ = pool;
const token = group.token.?;
group.token = null;
var node: *std.SinglyLinkedList.Node = @ptrCast(@alignCast(token));
while (true) {
const gc: *GroupClosure = @fieldParentPtr("node", node);
@ -523,6 +523,36 @@ fn groupCancel(userdata: ?*anyopaque, group: *Io.Group) void {
}
}
fn groupCancel(userdata: ?*anyopaque, group: *Io.Group, token: *anyopaque) void {
const pool: *Pool = @ptrCast(@alignCast(userdata));
const gpa = pool.allocator;
if (builtin.single_threaded) return;
{
var node: *std.SinglyLinkedList.Node = @ptrCast(@alignCast(token));
while (true) {
const gc: *GroupClosure = @fieldParentPtr("node", node);
gc.closure.requestCancel();
node = node.next orelse break;
}
}
const group_state: *std.atomic.Value(usize) = @ptrCast(&group.state);
const reset_event: *ResetEvent = @ptrCast(&group.context);
std.Thread.WaitGroup.waitStateless(group_state, reset_event);
{
var node: *std.SinglyLinkedList.Node = @ptrCast(@alignCast(token));
while (true) {
const gc: *GroupClosure = @fieldParentPtr("node", node);
const node_next = node.next;
gc.free(gpa);
node = node_next orelse break;
}
}
}
fn await(
userdata: ?*anyopaque,
any_future: *Io.AnyFuture,
@ -774,7 +804,7 @@ fn fileReadStreaming(userdata: ?*anyopaque, file: Io.File, data: [][]u8) Io.File
.SUCCESS => return nread,
.INTR => unreachable,
.INVAL => unreachable,
.FAULT => unreachable,
.FAULT => |err| return errnoBug(err),
.AGAIN => unreachable, // currently not support in WASI
.BADF => return error.NotOpenForReading, // can be a race condition
.IO => return error.InputOutput,
@ -796,7 +826,7 @@ fn fileReadStreaming(userdata: ?*anyopaque, file: Io.File, data: [][]u8) Io.File
.SUCCESS => return @intCast(rc),
.INTR => continue,
.INVAL => unreachable,
.FAULT => unreachable,
.FAULT => |err| return errnoBug(err),
.SRCH => return error.ProcessNotFound,
.AGAIN => return error.WouldBlock,
.BADF => return error.NotOpenForReading, // can be a race condition
@ -896,7 +926,7 @@ fn fileReadPositional(userdata: ?*anyopaque, file: Io.File, data: [][]u8, offset
.SUCCESS => return nread,
.INTR => unreachable,
.INVAL => unreachable,
.FAULT => unreachable,
.FAULT => |err| return errnoBug(err),
.AGAIN => unreachable,
.BADF => return error.NotOpenForReading, // can be a race condition
.IO => return error.InputOutput,
@ -922,7 +952,7 @@ fn fileReadPositional(userdata: ?*anyopaque, file: Io.File, data: [][]u8, offset
.SUCCESS => return @bitCast(rc),
.INTR => continue,
.INVAL => unreachable,
.FAULT => unreachable,
.FAULT => |err| return errnoBug(err),
.SRCH => return error.ProcessNotFound,
.AGAIN => return error.WouldBlock,
.BADF => return error.NotOpenForReading, // can be a race condition
@ -969,18 +999,19 @@ fn pwrite(userdata: ?*anyopaque, file: Io.File, buffer: []const u8, offset: posi
};
}
fn now(userdata: ?*anyopaque, clockid: posix.clockid_t) Io.ClockGetTimeError!Io.Timestamp {
fn now(userdata: ?*anyopaque, clockid: posix.clockid_t) Io.NowError!Io.Timestamp {
const pool: *Pool = @ptrCast(@alignCast(userdata));
try pool.checkCancel();
const timespec = try posix.clock_gettime(clockid);
return @enumFromInt(@as(i128, timespec.sec) * std.time.ns_per_s + timespec.nsec);
}
fn sleep(userdata: ?*anyopaque, clockid: posix.clockid_t, deadline: Io.Deadline) Io.SleepError!void {
fn sleep(userdata: ?*anyopaque, clockid: posix.clockid_t, timeout: Io.Timeout) Io.SleepError!void {
const pool: *Pool = @ptrCast(@alignCast(userdata));
const deadline_nanoseconds: i96 = switch (deadline) {
const deadline_nanoseconds: i96 = switch (timeout) {
.none => std.math.maxInt(i96),
.duration => |duration| duration.nanoseconds,
.timestamp => |timestamp| @intFromEnum(timestamp),
.deadline => |deadline| @intFromEnum(deadline),
};
var timespec: posix.timespec = .{
.sec = @intCast(@divFloor(deadline_nanoseconds, std.time.ns_per_s)),
@ -988,12 +1019,12 @@ fn sleep(userdata: ?*anyopaque, clockid: posix.clockid_t, deadline: Io.Deadline)
};
while (true) {
try pool.checkCancel();
switch (std.os.linux.E.init(std.os.linux.clock_nanosleep(clockid, .{ .ABSTIME = switch (deadline) {
.duration => false,
.timestamp => true,
switch (std.os.linux.E.init(std.os.linux.clock_nanosleep(clockid, .{ .ABSTIME = switch (timeout) {
.none, .duration => false,
.deadline => true,
} }, &timespec, &timespec))) {
.SUCCESS => return,
.FAULT => unreachable,
.FAULT => |err| return errnoBug(err),
.INTR => {},
.INVAL => return error.UnsupportedClock,
else => |err| return posix.unexpectedErrno(err),
@ -1278,7 +1309,7 @@ fn netReadPosix(userdata: ?*anyopaque, stream: Io.net.Stream, data: [][]u8) Io.n
fn netSend(
userdata: ?*anyopaque,
handle: Io.net.Socket.Handle,
address: Io.net.IpAddress,
address: *const Io.net.IpAddress,
data: []const u8,
) Io.net.Socket.SendError!void {
const pool: *Pool = @ptrCast(@alignCast(userdata));
@ -1293,15 +1324,15 @@ fn netSend(
fn netReceive(
userdata: ?*anyopaque,
handle: Io.net.Socket.Handle,
address: Io.net.IpAddress,
buffer: []u8,
) Io.net.Socket.ReceiveError!void {
timeout: Io.Timeout,
) Io.net.Socket.ReceiveTimeoutError!Io.net.ReceivedMessage {
const pool: *Pool = @ptrCast(@alignCast(userdata));
try pool.checkCancel();
_ = handle;
_ = address;
_ = buffer;
_ = timeout;
@panic("TODO");
}

View file

@ -134,13 +134,13 @@ pub const IpAddress = union(enum) {
}
}
pub fn eql(a: IpAddress, b: IpAddress) bool {
return switch (a) {
.ip4 => |a_ip4| switch (b) {
pub fn eql(a: *const IpAddress, b: *const IpAddress) bool {
return switch (a.*) {
.ip4 => |a_ip4| switch (b.*) {
.ip4 => |b_ip4| a_ip4.eql(b_ip4),
else => false,
},
.ip6 => |a_ip6| switch (b) {
.ip6 => |a_ip6| switch (b.*) {
.ip6 => |b_ip6| a_ip6.eql(b_ip6),
else => false,
},
@ -695,6 +695,11 @@ pub const Ip6Address = struct {
};
};
pub const ReceivedMessage = struct {
from: IpAddress,
len: usize,
};
pub const Interface = struct {
/// Value 0 indicates `none`.
index: u32,
@ -816,14 +821,31 @@ pub const Socket = struct {
return io.vtable.netSend(io.userdata, s.handle, dest, data);
}
pub const ReceiveError = error{} || Io.Cancelable;
pub const ReceiveError = error{} || Io.UnexpectedError || Io.Cancelable;
/// Transfers `data` from `source`, connectionless.
/// Waits for data. Connectionless.
///
/// Returned slice has same pointer as `buffer` with possibly shorter length.
pub fn receive(s: *const Socket, io: Io, source: *const IpAddress, buffer: []u8) ReceiveError![]u8 {
const n = try io.vtable.netReceive(io.userdata, s.handle, source, buffer);
return buffer[0..n];
/// See also:
/// * `receiveTimeout`
pub fn receive(s: *const Socket, io: Io, source: *const IpAddress, buffer: []u8) ReceiveError!ReceivedMessage {
return io.vtable.netReceive(io.userdata, s.handle, source, buffer, .none);
}
pub const ReceiveTimeoutError = ReceiveError || Io.Timeout.Error;
/// Waits for data. Connectionless.
///
/// Returns `error.Timeout` if no message arrives early enough.
///
/// See also:
/// * `receive`
pub fn receiveTimeout(
s: *const Socket,
io: Io,
buffer: []u8,
timeout: Io.Timeout,
) ReceiveTimeoutError!ReceivedMessage {
return io.vtable.netReceive(io.userdata, s.handle, buffer, timeout);
}
};

View file

@ -46,15 +46,13 @@ pub const LookupOptions = struct {
family: ?IpAddress.Family = null,
};
pub const LookupError = Io.Cancelable || Io.File.OpenError || Io.File.Reader.Error || error{
pub const LookupError = error{
UnknownHostName,
ResolvConfParseFailed,
// TODO remove from error set; retry a few times then report a different error
TemporaryNameServerFailure,
InvalidDnsARecord,
InvalidDnsAAAARecord,
NameServerFailure,
};
} || Io.NowError || IpAddress.BindError || Io.File.OpenError || Io.File.Reader.Error || Io.Cancelable;
pub const LookupResult = struct {
/// How many `LookupOptions.addresses_buffer` elements are populated.
@ -185,7 +183,7 @@ fn sortLookupResults(options: LookupOptions, result: LookupResult) !LookupResult
return result;
}
fn lookupDnsSearch(host_name: HostName, io: Io, options: LookupOptions) !LookupResult {
fn lookupDnsSearch(host_name: HostName, io: Io, options: LookupOptions) LookupError!LookupResult {
const rc = ResolvConf.init(io) catch return error.ResolvConfParseFailed;
// Count dots, suppress search when >=ndots or name ends in
@ -218,19 +216,17 @@ fn lookupDnsSearch(host_name: HostName, io: Io, options: LookupOptions) !LookupR
return lookupDns(io, lookup_canon_name, &rc, options);
}
const DnsReply = struct {
buf: [512]u8,
len: usize,
};
fn lookupDns(io: Io, lookup_canon_name: []const u8, rc: *const ResolvConf, options: LookupOptions) !LookupResult {
fn lookupDns(io: Io, lookup_canon_name: []const u8, rc: *const ResolvConf, options: LookupOptions) LookupError!LookupResult {
const family_records: [2]struct { af: IpAddress.Family, rr: u8 } = .{
.{ .af = .ip6, .rr = std.posix.RR.A },
.{ .af = .ip4, .rr = std.posix.RR.AAAA },
};
var query_buffers: [2][280]u8 = undefined;
var answer_buffers: [2][512]u8 = undefined;
var queries_buffer: [2][]const u8 = undefined;
var answers_buffer: [2][]const u8 = undefined;
var nq: usize = 0;
var next_answer_buffer: usize = 0;
for (family_records) |fr| {
if (options.family != fr.af) {
@ -241,41 +237,123 @@ fn lookupDns(io: Io, lookup_canon_name: []const u8, rc: *const ResolvConf, optio
}
}
const queries = queries_buffer[0..nq];
var replies_buffer: [2]DnsReply = undefined;
var replies: Io.Queue(DnsReply) = .init(&replies_buffer);
try rc.sendMessage(io, queries, &replies);
var ip4_mapped: [ResolvConf.max_nameservers]IpAddress = undefined;
var any_ip6 = false;
for (rc.nameservers(), &ip4_mapped) |*ns, *m| {
m.* = .{ .ip6 = .fromAny(ns.*) };
any_ip6 = any_ip6 or ns.* == .ip6;
}
var socket = s: {
if (any_ip6) ip6: {
const ip6_addr: IpAddress = .{ .ip6 = .unspecified(0) };
const socket = ip6_addr.bind(io, .{ .ip6_only = true, .mode = .dgram }) catch |err| switch (err) {
error.AddressFamilyUnsupported => break :ip6,
else => |e| return e,
};
break :s socket;
}
any_ip6 = false;
const ip4_addr: IpAddress = .{ .ip4 = .unspecified(0) };
const socket = try ip4_addr.bind(io, .{ .mode = .dgram });
break :s socket;
};
defer socket.close(io);
for (replies) |reply| {
if (reply.len < 4 or (reply[3] & 15) == 2) return error.TemporaryNameServerFailure;
if ((reply[3] & 15) == 3) return .empty;
if ((reply[3] & 15) != 0) return error.UnknownHostName;
const mapped_nameservers = if (any_ip6) ip4_mapped[0..rc.nameservers_len] else rc.nameservers();
const queries = queries_buffer[0..nq];
const answers = answers_buffer[0..queries.len];
for (answers) |*answer| answer.len = 0;
var now_ts = try io.now(.MONOTONIC);
const final_ts = now_ts.addDuration(.seconds(rc.timeout_seconds));
const attempt_duration: Io.Duration = .{
.nanoseconds = std.time.ns_per_s * @as(usize, rc.timeout_seconds) / rc.attempts,
};
send: while (now_ts.compare(.lt, final_ts)) : (now_ts = try io.now(.MONOTONIC)) {
var group: Io.Group = .init;
defer group.cancel(io);
for (queries, answers) |query, *answer| {
if (answer.len != 0) continue;
for (mapped_nameservers) |*ns| {
group.async(io, sendIgnoringResult, .{ io, socket.handle, ns, query });
}
}
const timeout: Io.Timeout = .{ .deadline = now_ts.addDuration(attempt_duration) };
while (true) {
const buf = &answer_buffers[next_answer_buffer];
const reply = socket.receiveTimeout(io, buf, timeout) catch |err| switch (err) {
error.Canceled => return error.Canceled,
error.Timeout => continue :send,
else => continue,
};
// Ignore non-identifiable packets.
if (reply.len < 4) continue;
// Ignore replies from addresses we didn't send to.
const ns = for (mapped_nameservers) |*ns| {
if (reply.from.eql(ns)) break ns;
} else {
continue;
};
const reply_msg = buf[0..reply.len];
// Find which query this answer goes with, if any.
const query, const answer = for (queries, answers) |query, *answer| {
if (reply_msg[0] == query[0] and reply_msg[1] == query[1]) break .{ query, answer };
} else {
continue;
};
if (answer.len != 0) continue;
// Only accept positive or negative responses; retry immediately on
// server failure, and ignore all other codes such as refusal.
switch (reply_msg[3] & 15) {
0, 3 => {
answer.* = reply_msg;
next_answer_buffer += 1;
if (next_answer_buffer == answers.len) break :send;
},
2 => {
group.async(io, sendIgnoringResult, .{ io, socket.handle, ns, query });
continue;
},
else => continue,
}
}
} else {
return error.NameServerFailure;
}
var addresses_len: usize = 0;
var canonical_name: ?HostName = null;
for (replies) |reply| {
var it = DnsResponse.init(reply) catch {
for (answers) |answer| {
var it = DnsResponse.init(answer) catch {
// TODO accept a diagnostics struct and append warnings
continue;
};
while (it.next() catch {
// TODO accept a diagnostics struct and append warnings
continue;
}) |answer| switch (answer.rr) {
}) |record| switch (record.rr) {
std.posix.RR.A => {
if (answer.data.len != 4) return error.InvalidDnsARecord;
if (record.data.len != 4) return error.InvalidDnsARecord;
options.addresses_buffer[addresses_len] = .{ .ip4 = .{
.bytes = answer.data[0..4].*,
.bytes = record.data[0..4].*,
.port = options.port,
} };
addresses_len += 1;
},
std.posix.RR.AAAA => {
if (answer.data.len != 16) return error.InvalidDnsAAAARecord;
if (record.data.len != 16) return error.InvalidDnsAAAARecord;
options.addresses_buffer[addresses_len] = .{ .ip6 = .{
.bytes = answer.data[0..16].*,
.bytes = record.data[0..16].*,
.port = options.port,
} };
addresses_len += 1;
@ -285,7 +363,7 @@ fn lookupDns(io: Io, lookup_canon_name: []const u8, rc: *const ResolvConf, optio
@panic("TODO");
//var tmp: [256]u8 = undefined;
//// Returns len of compressed name. strlen to get canon name.
//_ = try posix.dn_expand(packet, answer.data, &tmp);
//_ = try posix.dn_expand(packet, record.data, &tmp);
//const canon_name = mem.sliceTo(&tmp, 0);
//if (isValidHostName(canon_name)) {
// ctx.canon.items.len = 0;
@ -304,6 +382,10 @@ fn lookupDns(io: Io, lookup_canon_name: []const u8, rc: *const ResolvConf, optio
return error.NameServerFailure;
}
fn sendIgnoringResult(io: Io, socket_handle: Io.net.Socket.Handle, dest: *const IpAddress, msg: []const u8) void {
_ = io.vtable.netSend(io.userdata, socket_handle, dest, msg) catch {};
}
fn lookupHosts(host_name: HostName, io: Io, options: LookupOptions) !LookupResult {
const file = Io.File.openAbsolute(io, "/etc/hosts", .{}) catch |err| switch (err) {
error.FileNotFound,
@ -523,7 +605,7 @@ pub fn connectTcp(host_name: HostName, io: Io, port: u16) ConnectTcpError!Stream
pub const ResolvConf = struct {
attempts: u32,
ndots: u32,
timeout: Io.Duration,
timeout_seconds: u32,
nameservers_buffer: [max_nameservers]IpAddress,
nameservers_len: usize,
search_buffer: [max_len]u8,
@ -539,7 +621,7 @@ pub const ResolvConf = struct {
.search_buffer = undefined,
.search_len = 0,
.ndots = 1,
.timeout = .seconds(5),
.timeout_seconds = 5,
.attempts = 2,
};
@ -589,7 +671,7 @@ pub const ResolvConf = struct {
switch (std.meta.stringToEnum(Option, name) orelse continue) {
.ndots => rc.ndots = @min(value, 15),
.attempts => rc.attempts = @min(value, 10),
.timeout => rc.timeout = .seconds(@min(value, 60)),
.timeout => rc.timeout_seconds = @min(value, 60),
}
},
.nameserver => {
@ -621,68 +703,6 @@ pub const ResolvConf = struct {
fn nameservers(rc: *const ResolvConf) []const IpAddress {
return rc.nameservers_buffer[0..rc.nameservers_len];
}
fn sendMessage(
rc: *const ResolvConf,
io: Io,
queries: []const []const u8,
replies: *Io.Queue(DnsReply),
) !void {
var ip4_mapped: [ResolvConf.max_nameservers]IpAddress = undefined;
var any_ip6 = false;
for (rc.nameservers(), &ip4_mapped) |*ns, *m| {
m.* = .{ .ip6 = .fromAny(ns.*) };
any_ip6 = any_ip6 or ns.* == .ip6;
}
const socket = s: {
if (any_ip6) ip6: {
const ip6_addr: IpAddress = .{ .ip6 = .unspecified(0) };
const socket = ip6_addr.bind(io, .{ .ip6_only = true, .mode = .dgram }) catch |err| switch (err) {
error.AddressFamilyUnsupported => break :ip6,
else => |e| return e,
};
break :s socket;
}
any_ip6 = false;
const ip4_addr: IpAddress = .{ .ip4 = .unspecified(0) };
const socket = try ip4_addr.bind(io, .{ .mode = .dgram });
break :s socket;
};
defer socket.close();
const mapped_nameservers = if (any_ip6) ip4_mapped[0..rc.nameservers_len] else rc.nameservers();
var group: Io.Group = .init;
defer group.cancel();
for (queries) |query| {
for (mapped_nameservers) |*ns| {
group.async(sendOneMessage, .{ io, query, ns });
}
}
const deadline: Io.Deadline = .fromDuration(rc.timeout);
for (0..queries.len) |_| {
const msg = socket.receiveDeadline(deadline) catch |err| switch (err) {
error.Timeout => return error.Timeout,
error.Canceled => return error.Canceled,
else => continue,
};
_ = msg;
_ = replies;
@panic("TODO check msg for dns reply and put into replies queue");
}
}
fn sendOneMessage(
io: Io,
query: []const u8,
ns: *const IpAddress,
) void {
io.vtable.netSend(io.userdata, ns.*, &.{query}) catch |err| switch (err) {};
}
};
test ResolvConf {
@ -702,7 +722,7 @@ test ResolvConf {
.search_buffer = undefined,
.search_len = 0,
.ndots = 1,
.timeout = .seconds(5),
.timeout_seconds = 5,
.attempts = 2,
};