Bump version, update NEWS

Additional lines might have been passed to the server intact
as part of an argument, but we have /quote for that.

CMakeLists.txt

@@ -1,6 +1,11 @@
 # Ubuntu 18.04 LTS and OpenBSD 6.4
 cmake_minimum_required (VERSION 3.10)
-project (xK VERSION 1.5.0
+
+file (READ xK-version project_version)
+configure_file (xK-version xK-version.tag COPYONLY)
+string (STRIP "${project_version}" project_version)
+
+project (xK VERSION "${project_version}"
 	DESCRIPTION "IRC daemon, bot, TUI client and its web frontend" LANGUAGES C)
 
 # Options
@@ -18,9 +23,6 @@ if ("${CMAKE_C_COMPILER_ID}" MATCHES "GNU" OR CMAKE_COMPILER_IS_GNUCC)
 	set (CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wextra -Wno-unused-function")
 endif ()
 
-# Version
-set (project_version "${PROJECT_VERSION}")
-
 # Try to append commit ID if it follows a version tag.  It might be nicer if
 # we could also detect dirty worktrees but that's very hard to get right.
 # If we didn't need this for CPack, we could use add_custom_command to generate

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2014 - 2023, Přemysl Eric Janouch <p@janouch.name>
+Copyright (c) 2014 - 2024, Přemysl Eric Janouch <p@janouch.name>
 
 Permission to use, copy, modify, and/or distribute this software for any
 purpose with or without fee is hereby granted.

NEWS

@@ -1,4 +1,4 @@
-2.0.0 (Unreleased)
+2.0.0 (2024-07-28) "Perfect Is the Enemy of Good"
 
  * xD: now using SHA-256 for client certificate fingerprints
 
@@ -16,6 +16,8 @@
 
  * xC: replaced behaviour.save_on_quit with general.autosave
 
+ * xC: the server *.command configuration option now supports multiple lines
+
  * xC: improved pager integration capabilities
 
  * xC: unsolicited JOINs will no longer automatically activate the buffer
@@ -31,8 +33,14 @@
 
  * Added a web frontend for xC called xP
 
+ * Added a Win32 frontend for xC called xW
+
+ * Added a Cocoa frontend for xC called xM
+
  * Added a Go port of xD called xS
 
+ * Added a simple notifier called xN
+
 
 1.5.0 (2021-12-21) "The Show Must Go On"
 

README.adoc

@@ -1,9 +1,10 @@
 xK
 ==
 
-'xK' (chat kit) is an IRC software suite consisting of a daemon, bot, terminal
-client, and a web frontend for the client.  It's all you're ever going to
-need for chatting, so long as you can make do with slightly minimalist software.
+'xK' (chat kit) is an IRC software suite consisting of a daemon, bot, notifier,
+terminal client, and web/Windows/macOS frontends for the client.  It's all
+you're ever going to need for chatting, so long as you can make do with slightly
+minimalist software.
 
 They're all lean on dependencies, and offer a maximally permissive licence.
 
@@ -55,6 +56,10 @@ https://github.com/kiwiirc/webircgateway[].
 Any further development, such as P10 or TS6 linking for IRC services,
 or plugin support for arbitrary bridges, will happen here.
 
+xN
+--
+The IRC notifier, should you ever need to send automated messages from a script.
+
 xB
 --
 The IRC bot.  While originally intended to be a simple rewrite of my old GNU AWK
@@ -68,8 +73,10 @@ that easily to any program).
 
 Packages
 --------
-Regular releases are sporadic.  git master should be stable enough.  You can get
-a package with the latest development version from Archlinux's AUR.
+Regular releases are sporadic.  git master should be stable enough.
+You can get a package with the latest development version using Arch Linux's
+https://aur.archlinux.org/packages/xk-git[AUR],
+or as a https://git.janouch.name/p/nixexprs[Nix derivation].
 
 Building
 --------
@@ -135,14 +142,35 @@ For remote use, it's recommended to put 'xP' behind a reverse proxy, with TLS,
 and some form of HTTP authentication.  Pass the external URL of the WebSocket
 endpoint as the third command line argument in this case.
 
+xW
+~~
+The Win32 frontend is a separate CMake subproject that should be compiled
+using MinGW-w64.  To avoid having to specify the relay address each time you
+run it, create a shortcut for the executable and include the address in its
+_Target_ field:
+
+ C:\...\xW.exe 127.0.0.1 9000
+
+It works reasonably well starting with Windows 7.
+
+xM
+~~
+The Cocoa frontend is a separate CMake subproject that requires Xcode to build.
+It is currently not that usable.  The relay address can either be passed on
+the command line, or preset in the _defaults_ database:
+
+ $ defaults write name.janouch.xM relayHost 127.0.0.1
+ $ defaults write name.janouch.xM relayPort 9000
+
 Client Certificates
 -------------------
 'xC' will use the SASL EXTERNAL method to authenticate using the TLS client
 certificate specified by the respective server's `tls_cert` option if you add
 `sasl` to the `capabilities` option and the server supports this.
 
-'xD' uses SHA-256 fingerprints of TLS client certificates to authenticate users.
-To get the fingerprint from a certificate file in the required form, use:
+'xD' and 'xS' use SHA-256 fingerprints of TLS client certificates
+to authenticate users.  To get the fingerprint from a certificate file
+in the required form, use:
 
  $ openssl x509 -in public.pem -outform DER | sha256sum
 

test

@@ -1,5 +1,7 @@
 #!/usr/bin/expect -f
 # Very basic end-to-end testing for CI
+set tempdir [exec mktemp -d]
+set ::env(XDG_CONFIG_HOME) $tempdir
 
 # Run the daemon to test against
 system ./xD --write-default-cfg
@@ -27,7 +29,7 @@ expect "Option changed"
 send "/disconnect\n"
 expect "]"
 send "/connect\n"
-expect "Connection established"
+expect "Welcome to"
 
 # Try some chatting
 send "/join #test\n"

test-static

@@ -1,8 +1,16 @@
 #!/bin/sh
 # We don't use printf's percent notation with our custom logging mechanism,
-# so the compiler cannot check it for us like it usually does
+# so the compiler cannot check it for us like it usually does.
+#
+# In clang-query terms, the string we're interested in can be found through:
+#   set traversal IgnoreUnlessSpelledInSource
+#   set output dump
+#   match callExpr(callee(functionDecl(
+#     hasName("log_full"))),
+#     hasArgument(5, stringLiteral().bind("format")))
+# However, the tool is too restricted to be useful in a shell script.
 perl -n0777 - "$(dirname "$0")"/xC.c <<-'END'
-	while (/\blog_[^ ]+\s*\([^"()]*"[^"]*%[^%][^"]*"/gm) {
+	while (/\blog_[^ ]+\s*\([^"()]*"[^"]*%\w[^"]*"/gm) {
 		my ($p, $m) = ($`, $&);
 		printf "$ARGV:%d: suspicious log format string: %s...\n",
 			(1 + $p =~ tr/\n//), ($m =~ s/\s+/ /rg);

xB.c

@@ -1009,7 +1009,7 @@ is_valid_plugin_name (const char *name)
 	if (!*name)
 		return false;
 	for (const char *p = name; *p; p++)
-		if (!isgraph (*p) || *p == '/')
+		if (!isgraph ((uint8_t) *p) || *p == '/')
 			return false;
 	return true;
 }
@@ -1213,7 +1213,7 @@ parse_bot_command (const char *s, const char *command, const char **following)
 	s += command_len;
 
 	// Expect a word boundary, so that we don't respond to invalid things
-	if (isalnum (*s))
+	if (isalnum ((uint8_t) *s))
 		return false;
 
 	// Ignore any initial spaces; the rest is the command's argument

xC.c

@@ -1,7 +1,7 @@
 /*
  * xC.c: a terminal-based IRC client
  *
- * Copyright (c) 2015 - 2022, Přemysl Eric Janouch <p@janouch.name>
+ * Copyright (c) 2015 - 2024, Přemysl Eric Janouch <p@janouch.name>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -50,6 +50,7 @@ enum
 
 // fmemopen
 #define _POSIX_C_SOURCE 200809L
+#define _XOPEN_SOURCE 700
 
 #include "common.c"
 #include "xD-replies.c"
@@ -615,7 +616,7 @@ input_rl_buffer_add_history (void *input, input_buffer_t input_buffer,
 	// or temporarily switch histories.
 	if (!buffer->history)
 	{
-		bool at_end = history_offset == history_length;
+		bool at_end = where_history () == history_length;
 		add_history (line);
 		if (at_end)
 			next_history ();
@@ -8316,6 +8317,8 @@ irc_try_parse_welcome_for_userhost (struct server *s, const char *m)
 	strv_free (&v);
 }
 
+static void process_input
+	(struct app_context *, struct buffer *, const char *);
 static bool process_input_line
 	(struct app_context *, struct buffer *, const char *, int);
 static void on_autoaway_timer (struct app_context *ctx);
@@ -8344,7 +8347,7 @@ irc_on_registered (struct server *s, const char *nickname)
 	if (command)
 	{
 		log_server_debug (s, "Executing \"#s\"", command);
-		(void) process_input_line (s->ctx, s->buffer, command, 0);
+		(void) process_input (s->ctx, s->buffer, command);
 	}
 
 	int64_t command_delay = get_config_integer (s->config, "command_delay");
@@ -9438,6 +9441,9 @@ server_add (struct app_context *ctx,
 	str_map_set (&ctx->servers, s->name, s);
 	s->config = subtree;
 
+	relay_prepare_server_update (ctx, s);
+	relay_broadcast (ctx);
+
 	// Add a buffer and activate it
 	struct buffer *buffer = s->buffer = buffer_new (ctx->input,
 		BUFFER_SERVER, irc_make_buffer_name (s, NULL));
@@ -12936,6 +12942,16 @@ handle_command_kill (struct handler_args *a)
 	return true;
 }
 
+static bool
+handle_command_away (struct handler_args *a)
+{
+	if (*a->arguments)
+		irc_send (a->s, "AWAY :%s", a->arguments);
+	else
+		irc_send (a->s, "AWAY");
+	return true;
+}
+
 static bool
 handle_command_nick (struct handler_args *a)
 {
@@ -13001,7 +13017,6 @@ TRIVIAL_HANDLER (who,   "WHO")
 TRIVIAL_HANDLER (motd,  "MOTD")
 TRIVIAL_HANDLER (oper,  "OPER")
 TRIVIAL_HANDLER (stats, "STATS")
-TRIVIAL_HANDLER (away,  "AWAY")
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 
@@ -15470,7 +15485,7 @@ client_message_buffer_name (const struct relay_command_message *m)
 	switch (m->data.command)
 	{
 	case RELAY_COMMAND_BUFFER_COMPLETE:
-		return m->data.buffer_input.buffer_name.str;
+		return m->data.buffer_complete.buffer_name.str;
 	case RELAY_COMMAND_BUFFER_ACTIVATE:
 		return m->data.buffer_activate.buffer_name.str;
 	case RELAY_COMMAND_BUFFER_INPUT:
@@ -15542,14 +15557,13 @@ static void
 client_process_buffer_log
 	(struct client *c, uint32_t seq, struct buffer *buffer)
 {
-	struct relay_event_data_response *e = relay_prepare_response (c->ctx, seq);
-	e->data.command = RELAY_COMMAND_BUFFER_LOG;
-
+	// XXX: We log failures to the global buffer,
+	//   so the client just receives nothing if there is no log file.
+	struct str log = str_make ();
 	char *path = buffer_get_log_path (buffer);
 	FILE *fp = open_log_path (c->ctx, buffer, path);
 	if (fp)
 	{
-		struct str log = str_make ();
 		char buf[BUFSIZ];
 		size_t len;
 		while ((len = fread (buf, 1, sizeof buf, fp)))
@@ -15557,17 +15571,15 @@ client_process_buffer_log
 		if (ferror (fp))
 			log_global_error (c->ctx, "Failed to read `#l': #l",
 				path, strerror (errno));
-
-		// On overflow, it will later fail serialization.
-		e->data.buffer_log.log_len = MIN (UINT32_MAX, log.len);
-		e->data.buffer_log.log = (uint8_t *) str_steal (&log);
 		fclose (fp);
 	}
-
-	// XXX: We log failures to the global buffer,
-	//   so the client just receives nothing if there is no log file.
-
 	free (path);
+
+	struct relay_event_data_response *e = relay_prepare_response (c->ctx, seq);
+	e->data.command = RELAY_COMMAND_BUFFER_LOG;
+	// On overflow, it will later fail serialization (frame will be too long).
+	e->data.buffer_log.log_len = MIN (UINT32_MAX, log.len);
+	e->data.buffer_log.log = (uint8_t *) str_steal (&log);
 	relay_send (c);
 }
 
@@ -15855,6 +15867,7 @@ relay_start (struct app_context *ctx, char *address, struct error **e)
 	}
 
 	// Just try the first one, disregarding IPv4/IPv6 ordering.
+	// Use 0.0.0.0 or [::] to request either one specifically.
 	int fd = relay_listen_with_context (ctx, result, e);
 	freeaddrinfo (result);
 	if (fd == -1)
@@ -16090,7 +16103,11 @@ main (int argc, char *argv[])
 
 	// The following part is a bit brittle because of interdependencies
 	init_colors (&ctx);
-	if (format_mode)  format_input_and_die (&ctx);
+	if (format_mode)
+		format_input_and_die (&ctx);
+	if (!cur_term)
+		exit_fatal ("terminal initialization failed");
+
 	init_global_buffer (&ctx);
 	show_logo (&ctx);
 	setup_signal_handlers ();

xF.svg

@@ -1,8 +1,6 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
 <svg version="1.1" width="48" height="48" viewBox="0 0 48 48"
-   xmlns:xlink="http://www.w3.org/1999/xlink"
-   xmlns="http://www.w3.org/2000/svg"
-   xmlns:svg="http://www.w3.org/2000/svg">
+   xmlns="http://www.w3.org/2000/svg">
 
   <defs>
     <linearGradient id="background" x1="0" y1="0" x2="1" y2="1">

xK-version

@@ -0,0 +1 @@
+2.0.0

xM/CMakeLists.txt

@@ -0,0 +1,45 @@
+# Swift language support
+cmake_minimum_required (VERSION 3.15)
+
+file (READ ../xK-version project_version)
+configure_file (../xK-version xK-version.tag COPYONLY)
+string (STRIP "${project_version}" project_version)
+
+# There were two issues when building this from the main CMakeLists.txt:
+# a) renaming main.swift to xM.swift requires removing top-level statements,
+# b) there is a "redefinition of module 'FFI'" error.
+project (xM VERSION "${project_version}"
+	DESCRIPTION "Cocoa frontend for xC" LANGUAGES Swift)
+
+set (root "${PROJECT_SOURCE_DIR}/..")
+add_custom_command (OUTPUT xC-proto.swift
+	COMMAND env LC_ALL=C awk
+		-f ${root}/liberty/tools/lxdrgen.awk
+		-f ${root}/liberty/tools/lxdrgen-swift.awk
+		-v PrefixCamel=Relay
+		${root}/xC.lxdr > xC-proto.swift
+	DEPENDS
+		${root}/liberty/tools/lxdrgen.awk
+		${root}/liberty/tools/lxdrgen-swift.awk
+		${root}/xC.lxdr
+	COMMENT "Generating xC relay protocol code" VERBATIM)
+
+set (MACOSX_BUNDLE_GUI_IDENTIFIER name.janouch.${PROJECT_NAME})
+set (MACOSX_BUNDLE_ICON_FILE xM.icns)
+
+# Avoid including binary files in the repository by generating icons in code.
+# sips(1) + Javascript + iconutil(1) could probably also be used.
+find_program (SWIFT_EXECUTABLE swift REQUIRED)
+
+set (icon "${PROJECT_BINARY_DIR}/${MACOSX_BUNDLE_ICON_FILE}")
+add_custom_command (OUTPUT "${icon}"
+	COMMAND ${SWIFT_EXECUTABLE} "${PROJECT_SOURCE_DIR}/gen-icon.swift" "${icon}"
+	DEPENDS gen-icon.swift
+	COMMENT "Generating xM application icon" VERBATIM)
+set_source_files_properties ("${icon}" PROPERTIES
+	MACOSX_PACKAGE_LOCATION Resources)
+
+# Other requirements: macOS 10.14 for Network, and macOS 11 for Logger.
+set (CMAKE_Swift_LANGUAGE_VERSION 5)
+add_executable (xM MACOSX_BUNDLE
+	main.swift "${icon}" "${PROJECT_BINARY_DIR}/xC-proto.swift")

xM/gen-icon.swift

@@ -0,0 +1,96 @@
+// gen-icon.swift: generate a program icon for xM in the Apple icon format
+//
+// Copyright (c) 2023, Přemysl Eric Janouch <p@janouch.name>
+// SPDX-License-Identifier: 0BSD
+//
+// NSGraphicsContext mostly just weirdly wraps over Quartz,
+// so we do it all in Quartz directly.
+import CoreGraphics
+import Foundation
+import ImageIO
+import UniformTypeIdentifiers
+
+// Apple uses something that's close to a "quintic superellipse" in their icons,
+// but doesn't quite match. Either way, it looks better than rounded rectangles.
+func addSquircle(context: CGContext, bounds: CGRect) {
+	context.move(to: CGPoint(x: bounds.maxX, y: bounds.midY))
+	for theta in stride(from: 0.0, to: .pi * 2, by: .pi / 1e4) {
+		let x = pow(abs(cos(theta)), 2 / 5.0) * bounds.width / 2
+			* CGFloat(signOf: cos(theta), magnitudeOf: 1) + bounds.midX
+		let y = pow(abs(sin(theta)), 2 / 5.0) * bounds.height / 2
+			* CGFloat(signOf: sin(theta), magnitudeOf: 1) + bounds.midY
+		context.addLine(to: CGPoint(x: x, y: y))
+	}
+	context.closePath()
+}
+
+func drawIcon(scale: CGFloat) -> CGImage? {
+	let size = CGSizeMake(1024, 1024)
+
+	let colorspace = CGColorSpaceCreateDeviceRGB()
+	let context = CGContext(data: nil,
+		width: Int(size.width * scale), height: Int(size.height * scale),
+		bitsPerComponent: 8, bytesPerRow: 0, space: colorspace,
+		bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue)!
+	context.scaleBy(x: scale, y: scale)
+
+	let bounds = CGRectMake(100, 100, size.width - 200, size.height - 200)
+	addSquircle(context: context, bounds: bounds)
+	let squircle = context.path!
+
+	// Gradients don't draw shadows, so draw it separately.
+	context.saveGState()
+	context.setShadow(offset: CGSizeMake(0, -12).applying(context.ctm),
+		blur: 28 * scale, color: CGColor(gray: 0, alpha: 0.5))
+	context.setFillColor(CGColor(red: 1, green: 0x55p-8, blue: 0, alpha: 1))
+	context.fillPath()
+	context.restoreGState()
+
+	context.saveGState()
+	context.addPath(squircle)
+	context.clip()
+	context.drawLinearGradient(
+		CGGradient(colorsSpace: colorspace, colors: [
+			CGColor(red: 1, green: 0x00p-8, blue: 0, alpha: 1),
+			CGColor(red: 1, green: 0xaap-8, blue: 0, alpha: 1)
+		] as CFArray, locations: [0, 1])!,
+		start: CGPointMake(0, 100), end: CGPointMake(0, size.height - 100),
+		options: CGGradientDrawingOptions(rawValue: 0))
+	context.restoreGState()
+
+	context.move(to: CGPoint(x: size.width * 0.30, y: size.height * 0.30))
+	context.addLine(to: CGPoint(x: size.width * 0.30, y: size.height * 0.70))
+	context.addLine(to: CGPoint(x: size.width * 0.575, y: size.height * 0.425))
+	context.move(to: CGPoint(x: size.width * 0.70, y: size.height * 0.30))
+	context.addLine(to: CGPoint(x: size.width * 0.70, y: size.height * 0.70))
+	context.addLine(to: CGPoint(x: size.width * 0.425, y: size.height * 0.425))
+	context.setLineWidth(80)
+	context.setLineCap(.round)
+	context.setLineJoin(.round)
+	context.setStrokeColor(CGColor.white)
+	context.strokePath()
+	return context.makeImage()
+}
+
+if CommandLine.arguments.count != 2 {
+	print("Usage: \(CommandLine.arguments.first!) OUTPUT.icns")
+	exit(EXIT_FAILURE)
+}
+
+let filename = CommandLine.arguments[1]
+
+let macOSSizes: Array<CGFloat> = [16, 32, 128, 256, 512]
+let icns = CGImageDestinationCreateWithURL(
+	URL(fileURLWithPath: filename) as CFURL,
+	UTType.icns.identifier as CFString, macOSSizes.count * 2, nil)!
+for size in macOSSizes {
+	CGImageDestinationAddImage(icns, drawIcon(scale: size / 1024.0)!, nil)
+	CGImageDestinationAddImage(icns, drawIcon(scale: size / 1024.0 * 2)!, [
+			kCGImagePropertyDPIWidth: 144,
+			kCGImagePropertyDPIHeight: 144,
+		] as CFDictionary)
+}
+if !CGImageDestinationFinalize(icns) {
+	print("ICNS finalization failed.")
+	exit(EXIT_FAILURE)
+}

xN/.gitignore

@@ -0,0 +1,3 @@
+/xN
+/xN.1
+/irc.go

xN/Makefile

@@ -0,0 +1,21 @@
+.POSIX:
+.SUFFIXES:
+AWK = env LC_ALL=C awk
+
+outputs = irc.go xN xN.1
+all: $(outputs)
+
+# If we want to keep module dependencies separate, we don't have many options.
+# Symlinking seems to work good enough.
+irc.go: ../xS/irc.go
+	ln -sf ../xS/irc.go $@
+
+xN: xN.go ../xK-version irc.go
+	go build -ldflags "-X 'main.projectVersion=$$(cat ../xK-version)'" -o $@
+xN.1: ../xK-version ../liberty/tools/asciiman.awk xN.adoc
+	env "asciidoc-release-version=$$(cat ../xK-version)" \
+		$(AWK) -f ../liberty/tools/asciiman.awk xN.adoc > $@
+test: all
+	go test
+clean:
+	rm -f $(outputs)

xN/go.mod

@@ -0,0 +1,3 @@
+module janouch.name/xK/xN
+
+go 1.19

xN/xN.adoc

@@ -0,0 +1,86 @@
+xN(1)
+=====
+:doctype: manpage
+:manmanual: xK Manual
+:mansource: xK {release-version}
+
+Name
+----
+xN - IRC notifier
+
+Synopsis
+--------
+*xN* [_OPTION_]... IRC-URL...
+
+Description
+-----------
+*xN* is a simple IRC notifier, sending the text it receives on its standard
+input to all IRC targets specified by its command line arguments.
+
+The input text is forced to validate as UTF-8, and it is _not_ split
+automatically to comply with the maximum IRC message length.
+Thus, make sure to make the lines short, or they will be trimmed by the servers.
+
+*xN* does not attempt to appease flood detectors.
+
+Options
+-------
+*-debug*::
+	Print incoming IRC traffic, which may help in debugging any issues.
+
+*-version*::
+	Output version information and exit.
+
+URL format
+----------
+*xN* accepts URLs describing IRC users and channels, roughly as specified by
+the Internet Draft _draft-butcher-irc-url-04.txt_.  Note, however, that close
+to no validation is done on these, and you should not pass URLs from untrusted
+sources, so as to avoid command or parameter injection.
+
+Any provided username will be propagated to the nickname, username,
+and realname.  The default value for these is the name of your system user.
+
+As an extension, you may use the following options:
+
+*skipjoin*::
+	Do not JOIN channels before sending messages to them.
+	This requires channels to allow external messages
+	(which are disabled by channel mode *+n*).
+*usenotice*::
+	Send a NOTICE rather than a PRIVMSG, which distinguishes automated messages,
+	and is more appropriate for bots.
+
+Examples
+--------
+ $ uptime | xN 'irc://uptime@localhost/%23watch?skipjoin&usenotice'
+
+Send *uptime*(1) information as an external notice to channel *#watch*
+on the local server, using the standard port *6667*.
+
+ $ fortune -s | xN ircs://ohayou@irc.libera.chat/john,isuser
+
+Greet user *john* with a fortune for this day.  In compliance with _RFC 7194_,
+the default TLS port is assumed to be *6697*.
+
+ $ xN 'ircs://agent:Password123@irc.cia.gov:1337/#hq?key=123456' <<EOF
+ The red fox trots quietly at midnight.
+ EOF
+
+Connect over TLS to *irc.cia.gov* on port *1337*, use *Password123*
+as the server password, register as user *agent*,
+join channel *#hq* using the channel key *123456*,
+and send a very secret message.
+
+Reporting bugs
+--------------
+Use https://git.janouch.name/p/xK to report bugs, request features,
+or submit pull requests.
+
+See also
+--------
+_Uniform Resource Locator Schemes for Internet Relay Chat Entities_,
+https://datatracker.ietf.org/doc/html/draft-butcher-irc-url-04[].
+
+_Default Port for Internet Relay Chat (IRC) via TLS/SSL_,
+https://datatracker.ietf.org/doc/html/rfc7194[].

xN/xN.go

@@ -0,0 +1,279 @@
+//
+// Copyright (c) 2024, Přemysl Eric Janouch <p@janouch.name>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+// xN is a simple IRC notifier.
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/tls"
+	"errors"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"net"
+	"net/url"
+	"os"
+	"os/user"
+	"strconv"
+	"strings"
+)
+
+const projectName = "xN"
+
+var projectVersion = "?"
+
+var debugMode = false
+
+type parameters struct {
+	conn      net.Conn // underlying network connection
+	username  string   // nickname + username + realname
+	password  string   // server password
+	target    string   // where to send text
+	isuser    bool     // the target is a user rather than a channel
+	chankey   string   // channel key
+	skipjoin  bool     // whether to send external messages to channels
+	usenotice bool     // whether to use NOTICE rather than PRIVMSG
+	message   []string // lines of the message to send
+}
+
+func (p *parameters) send(command string, args ...string) error {
+	var buf bytes.Buffer
+	buf.WriteString(command)
+	for i, arg := range args {
+		buf.WriteRune(' ')
+		if i+1 == len(args) {
+			buf.WriteRune(':')
+		}
+		buf.WriteString(arg)
+	}
+	buf.WriteString("\r\n")
+	_, err := p.conn.Write(buf.Bytes())
+	return err
+}
+
+const (
+	rplWELCOME       = "001"
+	errNICKNAMEINUSE = "433"
+)
+
+func notify(p *parameters) error {
+	// The intro should comfortably fit in the TCP send buffer whole.
+	if p.password != "" {
+		p.send("PASS", p.password)
+	}
+	p.send("USER", p.username, "0", "*", p.username)
+	p.send("NICK", p.username)
+
+	scanner, nickCounter, issue := bufio.NewScanner(p.conn), 1, ""
+	for scanner.Scan() {
+		if debugMode {
+			log.Println(scanner.Text())
+		}
+
+		m := ircParseMessage(scanner.Text())
+		switch m.command {
+		case "PING":
+			p.send("PONG", m.params...)
+		case rplWELCOME:
+			if !p.isuser && !p.skipjoin {
+				if p.chankey != "" {
+					p.send("JOIN", p.target, p.chankey)
+				} else {
+					p.send("JOIN", p.target)
+				}
+			}
+			for _, line := range p.message {
+				if p.usenotice {
+					p.send("NOTICE", p.target, line)
+				} else {
+					p.send("PRIVMSG", p.target, line)
+				}
+			}
+			p.send("QUIT")
+		case errNICKNAMEINUSE:
+			p.send("NICK", fmt.Sprintf("%s%d", p.username, nickCounter))
+			nickCounter++
+		default:
+			// Prevent hanging on unsuccessful registrations.
+			numeric, _ := strconv.Atoi(m.command)
+			if numeric >= 400 && numeric <= 599 {
+				if len(m.params) > 1 {
+					issue = strings.Join(m.params[1:], " ")
+				} else {
+					issue = strings.Join(m.params, " ")
+				}
+				p.send("QUIT")
+			}
+		}
+	}
+	if err := scanner.Err(); err != nil {
+		return err
+	}
+	if issue != "" {
+		return errors.New(issue)
+	}
+	return nil
+}
+
+func parse(rawURL string, text []byte) (
+	p parameters, connect func() (net.Conn, error), err error) {
+	u, err := url.Parse(rawURL)
+	if err != nil {
+		return p, nil, err
+	} else if !u.IsAbs() || u.Opaque != "" {
+		return p, nil, errors.New("need an absolute URL")
+	} else if u.Path == "/" && u.Fragment != "" {
+		// Try to handle the common but degenerate case.
+		fragment := "%23" + u.Fragment
+		u.Fragment, u.RawFragment = "", ""
+		if u, err = url.Parse(u.String() + fragment); err != nil {
+			return p, nil, err
+		}
+	}
+
+	// Figure out registration details.
+	p.username = projectName
+	if u, _ := user.Current(); u != nil {
+		p.username = u.Username
+	}
+	if u.User.Username() != "" {
+		p.username = u.User.Username()
+	}
+
+	p.password, _ = u.User.Password()
+
+	// Figure out the target, which for our intents must accept messages.
+	path, _ := strings.CutPrefix(u.Path, "/")
+	elements := strings.Split(path, ",")
+	if path == "" || elements[0] == "" {
+		return p, nil, errors.New("unspecified entity")
+	}
+
+	// The last entity type wins.
+	p.target, p.isuser = elements[0], false
+	for _, typ := range elements[1:] {
+		switch typ {
+		case "isuser":
+			p.isuser = true
+		case "ischannel":
+			p.isuser = false
+		case "isserver":
+			// We do not support network names, and this is the default.
+		default:
+			return p, nil, errors.New("unsupported type: " + typ)
+		}
+	}
+	if p.isuser {
+		if i := strings.IndexAny(p.target, "!@"); i != -1 {
+			p.target = p.target[:i]
+		}
+	} else if !strings.HasPrefix(p.target, "#") {
+		// TODO(p): We should consult RPL_ISUPPORT rather than guess,
+		// though other prefixes are rare.
+		p.target = "#" + p.target
+	}
+
+	// Note that the draft RFC wants these to be case-insensitive.
+	p.chankey = u.Query().Get("key")
+	// Being able to skip channel join is our own requirement and invention,
+	// as are notices (names taken from Travis CI configuration).
+	p.skipjoin = u.Query().Has("skipjoin")
+	p.usenotice = u.Query().Has("usenotice")
+
+	// Ensure valid LF-separated UTF-8, and split it at lines.
+	sanitized := strings.ReplaceAll(string([]rune(string(text))), "\r", "\n")
+	for _, line := range strings.Split(sanitized, "\n") {
+		if line != "" {
+			p.message = append(p.message, line)
+		}
+	}
+
+	hostname, port := u.Hostname(), u.Port()
+	switch u.Scheme {
+	case "irc":
+		if port == "" {
+			port = "6667"
+		}
+		connect = func() (net.Conn, error) {
+			return net.Dial("tcp", net.JoinHostPort(hostname, port))
+		}
+	case "ircs":
+		if port == "" {
+			port = "6697"
+		}
+		connect = func() (net.Conn, error) {
+			return tls.Dial("tcp", net.JoinHostPort(hostname, port), nil)
+		}
+	default:
+		err = errors.New("unsupported scheme: " + u.Scheme)
+	}
+	return
+}
+
+// notifyByURL sends the given text to the IRC server specified by a URL.
+// See draft-butcher-irc-url-04.txt for the URL scheme specification
+// this function loosely follows.
+func notifyByURL(rawURL string, text []byte) error {
+	p, connect, err := parse(rawURL, text)
+	if p.conn, err = connect(); err != nil {
+		return err
+	}
+	defer p.conn.Close()
+	return notify(&p)
+}
+
+func main() {
+	flag.BoolVar(&debugMode, "debug", false, "run in verbose debug mode")
+	version := flag.Bool("version", false, "show version and exit")
+
+	flag.Usage = func() {
+		f := flag.CommandLine.Output()
+		fmt.Fprintf(f, "Usage: %s [OPTION]... URL...\n", os.Args[0])
+		flag.PrintDefaults()
+	}
+	flag.Parse()
+	if flag.NArg() < 1 {
+		flag.Usage()
+		os.Exit(2)
+	}
+
+	if *version {
+		fmt.Printf("%s %s\n", projectName, projectVersion)
+		return
+	}
+
+	text, err := io.ReadAll(os.Stdin)
+	if err != nil {
+		log.Fatalln(err)
+	}
+
+	status := 0
+	for _, rawURL := range flag.Args() {
+		if err := notifyByURL(rawURL, text); err != nil {
+			status = 1
+
+			var ue *url.Error
+			if errors.As(err, &ue) {
+				log.Println(err)
+			} else {
+				log.Printf("notify %q: %s\n", rawURL, err)
+			}
+		}
+	}
+	os.Exit(status)
+}

xN/xN_test.go

@@ -0,0 +1,98 @@
+//
+// Copyright (c) 2024, Přemysl Eric Janouch <p@janouch.name>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+package main
+
+import "testing"
+
+func TestParseURL(t *testing.T) {
+	for _, rawURL := range []string{
+		`irc:server/channel`,
+		`irc://server/channel,isnetwork`,
+		`ircs://ssl.ircnet.io`,
+		`ircs://ssl.ircnet.io/`,
+		`http://server/path`,
+	} {
+		if _, _, err := parse(rawURL, nil); err == nil {
+			t.Errorf("%q should not parse\n", rawURL)
+		}
+	}
+
+	for _, test := range []struct {
+		rawURL string
+		p      parameters
+	}{
+		{
+			rawURL: `irc://uptime@localhost/%23watch?skipjoin&usenotice`,
+			p: parameters{
+				username:  "uptime",
+				target:    "#watch",
+				skipjoin:  true,
+				usenotice: true,
+			},
+		},
+		{
+			rawURL: `ircs://ohayou@irc.libera.chat/john,isuser,isserver`,
+			p: parameters{
+				username: "ohayou",
+				target:   "john",
+				isuser:   true,
+			},
+		},
+		{
+			rawURL: `ircs://agent:Password123@irc.cia.gov:1337/#hq?key=123456`,
+			p: parameters{
+				username: "agent",
+				password: "Password123",
+				target:   "#hq",
+				chankey:  "123456",
+			},
+		},
+	} {
+		p, _, err := parse(test.rawURL, nil)
+		if err != nil {
+			t.Errorf("%q should parse, got: %s\n", test.rawURL, err)
+			continue
+		}
+		if p.username != test.p.username {
+			t.Errorf("%q: username: %v ≠ %v\n",
+				test.rawURL, p.username, test.p.username)
+		}
+		if p.password != test.p.password {
+			t.Errorf("%q: password: %v ≠ %v\n",
+				test.rawURL, p.password, test.p.password)
+		}
+		if p.target != test.p.target {
+			t.Errorf("%q: target: %v ≠ %v\n",
+				test.rawURL, p.target, test.p.target)
+		}
+		if p.isuser != test.p.isuser {
+			t.Errorf("%q: isuser: %v ≠ %v\n",
+				test.rawURL, p.isuser, test.p.isuser)
+		}
+		if p.chankey != test.p.chankey {
+			t.Errorf("%q: chankey: %v ≠ %v\n",
+				test.rawURL, p.chankey, test.p.chankey)
+		}
+		if p.skipjoin != test.p.skipjoin {
+			t.Errorf("%q: skipjoin: %v ≠ %v\n",
+				test.rawURL, p.skipjoin, test.p.skipjoin)
+		}
+		if p.usenotice != test.p.usenotice {
+			t.Errorf("%q: usenotice: %v ≠ %v\n",
+				test.rawURL, p.usenotice, test.p.usenotice)
+		}
+	}
+}

xP/public/xP.js

@@ -197,6 +197,14 @@ function bufferResetStats(b) {
 	b.highlighted = false
 }
 
+function bufferPopExcessLines(b) {
+	// Let "new" messages be, if only because pulling the log file
+	// is much more problematic in the web browser than in xC.
+	// TODO: Make the limit configurable, or extract general.backlog_limit.
+	const old = b.lines.length - b.newMessages - b.newUnimportantMessages
+	b.lines.splice(0, old - 1000)
+}
+
 function bufferActivate(name) {
 	rpc.send({command: 'BufferActivate', bufferName: name})
 }
@@ -294,6 +302,13 @@ rpcEventHandlers.set(Relay.Event.BufferLine, e => {
 			b.newMessages++
 	}
 
+	// XXX: In its unkeyed diff algorithm, Mithril.js can only efficiently
+	// deal with common prefixes, i.e., indefinitely growing buffers.
+	// But we don't want to key all children of Buffer,
+	// so only trim buffers while they are, or once they become invisible.
+	if (e.bufferName != bufferCurrent)
+		bufferPopExcessLines(b)
+
 	if (e.leakToActive) {
 		let bc = buffers.get(bufferCurrent)
 		bc.lines.push({...line, leaked: true})
@@ -336,7 +351,7 @@ rpcEventHandlers.set(Relay.Event.BufferStats, e => {
 	if (b === undefined)
 		return
 
-	b.newMessages = e.newMessages,
+	b.newMessages = e.newMessages
 	b.newUnimportantMessages = e.newUnimportantMessages
 	b.highlighted = e.highlighted
 })
@@ -344,6 +359,11 @@ rpcEventHandlers.set(Relay.Event.BufferStats, e => {
 rpcEventHandlers.set(Relay.Event.BufferRename, e => {
 	buffers.set(e.new, buffers.get(e.bufferName))
 	buffers.delete(e.bufferName)
+
+	if (e.bufferName === bufferCurrent)
+		bufferCurrent = e.new
+	if (e.bufferName === bufferLast)
+		bufferLast = e.new
 })
 
 rpcEventHandlers.set(Relay.Event.BufferRemove, e => {
@@ -354,8 +374,16 @@ rpcEventHandlers.set(Relay.Event.BufferRemove, e => {
 
 rpcEventHandlers.set(Relay.Event.BufferActivate, e => {
 	let old = buffers.get(bufferCurrent)
-	if (old !== undefined)
+	if (old !== undefined) {
 		bufferResetStats(old)
+		bufferPopExcessLines(old)
+	}
+
+	// Initial sync: trim all buffers to our limit, just for consistency.
+	if (bufferCurrent === undefined) {
+		for (let b of buffers.values())
+			bufferPopExcessLines(b)
+	}
 
 	bufferLast = bufferCurrent
 	let b = buffers.get(e.bufferName)
@@ -501,7 +529,8 @@ let Content = {
 		while ((match = re.exec(text)) !== null) {
 			if (end < match.index)
 				a.push(m('span', attrs, text.substring(end, match.index)))
-			a.push(m('a[target=_blank]', {href: match[0], ...attrs}, match[0]))
+			a.push(m('a[target=_blank][rel=noreferrer]',
+				{href: match[0], ...attrs}, match[0]))
 			end = re.lastIndex
 		}
 		if (end < text.length)
@@ -664,6 +693,12 @@ let Buffer = {
 			const dom = event.target
 			bufferAutoscroll =
 				dom.scrollTop + dom.clientHeight + 1 >= dom.scrollHeight
+
+			let b = buffers.get(bufferCurrent)
+			if (b !== undefined && b.highlighted && !bufferAutoscroll) {
+				b.highlighted = false
+				m.redraw()
+			}
 		}}, lines)
 	},
 }
@@ -679,7 +714,8 @@ let Log = {
 		while ((match = re.exec(text)) !== null) {
 			if (end < match.index)
 				a.push(text.substring(end, match.index))
-			a.push(m('a[target=_blank]', {href: match[0]}, match[0]))
+			a.push(m('a[target=_blank][rel=noreferrer]',
+				{href: match[0]}, match[0]))
 			end = re.lastIndex
 		}
 		if (end < text.length)
@@ -967,7 +1003,7 @@ let Input = {
 		rpc.send({command: 'Active'})
 
 		let b = buffers.get(bufferCurrent)
-		if (b === undefined)
+		if (b === undefined || event.isComposing)
 			return
 
 		let textarea = event.currentTarget
@@ -1013,10 +1049,23 @@ let Input = {
 		} else if (!event.altKey && !event.ctrlKey && !event.metaKey &&
 				!event.shiftKey) {
 			handled = true
-			switch (event.keyCode) {
-			case 9:   success = Input.complete(b, textarea); break
-			case 13:  success = Input.submit(b, textarea);   break
-			default:  handled = false
+			switch (event.key) {
+			case 'PageUp':
+				Array.from(document.getElementsByClassName('buffer'))
+					.forEach(b => b.scrollBy(0, -b.clientHeight))
+				break
+			case 'PageDown':
+				Array.from(document.getElementsByClassName('buffer'))
+					.forEach(b => b.scrollBy(0, +b.clientHeight))
+				break
+			case 'Tab':
+				success = Input.complete(b, textarea);
+				break
+			case 'Enter':
+				success = Input.submit(b, textarea);
+				break
+			default:
+				handled = false
 			}
 		}
 		if (!success)

xS/.gitignore

@@ -1,2 +1,3 @@
 /xS
 /xS-replies.go
+/xS.1

xS/Makefile

@@ -2,16 +2,17 @@
 .SUFFIXES:
 AWK = env LC_ALL=C awk
 
-outputs = xS xS-version.go xS-replies.go
+outputs = xS xS-replies.go xS.1
 all: $(outputs)
 
-xS: xS.go xS-version.go xS-replies.go
-	go build -o $@
-xS-version.go: ../liberty/tools/cmake-parser.awk \
-	xS-gen-version.awk ../CMakeLists.txt
-	$(AWK) -f ../liberty/tools/cmake-parser.awk \
-		-f xS-gen-version.awk ../CMakeLists.txt > $@
+xS: xS.go ../xK-version xS-replies.go
+	go build -ldflags "-X 'main.projectVersion=$$(cat ../xK-version)'" -o $@
 xS-replies.go: xS-gen-replies.awk xS-replies
 	$(AWK) -f xS-gen-replies.awk xS-replies > $@
+xS.1: ../xK-version ../liberty/tools/asciiman.awk xS.adoc
+	env "asciidoc-release-version=$$(cat ../xK-version)" \
+		$(AWK) -f ../liberty/tools/asciiman.awk xS.adoc > $@
+test: all
+	go test
 clean:
 	rm -f $(outputs)

xS/irc.go

@@ -0,0 +1,132 @@
+package main
+
+import (
+	"path/filepath"
+	"regexp"
+	"strings"
+)
+
+func ircToLower(c byte) byte {
+	switch c {
+	case '[':
+		return '{'
+	case ']':
+		return '}'
+	case '\\':
+		return '|'
+	case '~':
+		return '^'
+	}
+	if c >= 'A' && c <= 'Z' {
+		return c + ('a' - 'A')
+	}
+	return c
+}
+
+func ircToUpper(c byte) byte {
+	switch c {
+	case '{':
+		return '['
+	case '}':
+		return ']'
+	case '|':
+		return '\\'
+	case '^':
+		return '~'
+	}
+	if c >= 'a' && c <= 'z' {
+		return c - ('a' - 'A')
+	}
+	return c
+}
+
+// Convert identifier to a canonical form for case-insensitive comparisons.
+// ircToUpper is used so that statically initialized maps can be in uppercase.
+func ircToCanon(ident string) string {
+	var canon []byte
+	for _, c := range []byte(ident) {
+		canon = append(canon, ircToUpper(c))
+	}
+	return string(canon)
+}
+
+func ircEqual(s1, s2 string) bool {
+	return ircToCanon(s1) == ircToCanon(s2)
+}
+
+func ircFnmatch(pattern string, s string) bool {
+	pattern, s = ircToCanon(pattern), ircToCanon(s)
+	// FIXME: This should not support [] ranges and handle '/' specially.
+	// We could translate the pattern to a regular expression.
+	matched, _ := filepath.Match(pattern, s)
+	return matched
+}
+
+var reMsg = regexp.MustCompile(
+	`^(?:@([^ ]*) +)?(?::([^! ]*)(?:!([^@]*)@([^ ]*))? +)?([^ ]+)(.*)?$`)
+var reArgs = regexp.MustCompile(`:.*| [^: ][^ ]*`)
+
+type message struct {
+	tags    map[string]string // IRC 3.2 message tags
+	nick    string            // optional nickname
+	user    string            // optional username
+	host    string            // optional hostname or IP address
+	command string            // command name
+	params  []string          // arguments
+}
+
+func ircUnescapeMessageTag(value string) string {
+	var buf []byte
+	escape := false
+	for i := 0; i < len(value); i++ {
+		if escape {
+			switch value[i] {
+			case ':':
+				buf = append(buf, ';')
+			case 's':
+				buf = append(buf, ' ')
+			case 'r':
+				buf = append(buf, '\r')
+			case 'n':
+				buf = append(buf, '\n')
+			default:
+				buf = append(buf, value[i])
+			}
+			escape = false
+		} else if value[i] == '\\' {
+			escape = true
+		} else {
+			buf = append(buf, value[i])
+		}
+	}
+	return string(buf)
+}
+
+func ircParseMessageTags(tags string, out map[string]string) {
+	for _, tag := range strings.Split(tags, ";") {
+		if tag == "" {
+			// Ignore empty.
+		} else if equal := strings.IndexByte(tag, '='); equal < 0 {
+			out[tag] = ""
+		} else {
+			out[tag[:equal]] = ircUnescapeMessageTag(tag[equal+1:])
+		}
+	}
+}
+
+func ircParseMessage(line string) *message {
+	m := reMsg.FindStringSubmatch(line)
+	if m == nil {
+		return nil
+	}
+
+	msg := message{nil, m[2], m[3], m[4], m[5], nil}
+	if m[1] != "" {
+		msg.tags = make(map[string]string)
+		ircParseMessageTags(m[1], msg.tags)
+	}
+	for _, x := range reArgs.FindAllString(m[6], -1) {
+		msg.params = append(msg.params, x[1:])
+	}
+	return &msg
+}

xS/xS-gen-version.awk

@@ -1,14 +0,0 @@
-# xS-gen-version.awk: extract version information from the CMake script
-#
-# Copyright (c) 2022, Přemysl Eric Janouch <p@janouch.name>
-# SPDX-License-Identifier: 0BSD
-
-Command == "project" {
-	for (i = 2; i in Args; i++)
-		if (Args[i] == "VERSION") {
-			print "package main"
-			print ""
-			print "const projectVersion = `" Args[++i] "`"
-			exit
-		}
-}

xS/xS.adoc

@@ -0,0 +1,57 @@
+xS(1)
+=====
+:doctype: manpage
+:manmanual: xK Manual
+:mansource: xK {release-version}
+
+Name
+----
+xS - IRC daemon
+
+Synopsis
+--------
+*xS* [_OPTION_]...
+
+Description
+-----------
+*xS* is a basic IRC daemon for single-server networks, suitable for testing
+and private use.  When run without a configuration file, it will start listening
+on the standard port 6667 and the "any" address.
+
+Options
+-------
+*-debug*::
+	Do not daemonize, print more information on the standard error stream
+	to help debug various issues.
+
+*-systemd*::
+	Log using the format specified in *sd-daemon*(3).
+
+*-h*, *-help*::
+	Display a help message and exit.
+
+*-version*::
+	Output version information and exit.
+
+*-writedefaultcfg*::
+	Write a configuration file with defaults, show its path and exit.
++
+The file will be appropriately commented.
+
+Files
+-----
+*xS* follows the XDG Base Directory Specification.
+
+_~/.config/xS/xS.conf_::
+_/etc/xdg/xS/xS.conf_::
+	The daemon's configuration file.  Use the *-writedefaultcfg* option
+	to create a new one for editing.
+
+Reporting bugs
+--------------
+Use https://git.janouch.name/p/xK to report bugs, request features,
+or submit pull requests.
+
+See also
+--------
+*sd-daemon*(3)

xS/xS.go

@@ -42,6 +42,8 @@ import (
 
 const projectName = "xS"
 
+var projectVersion = "?"
+
 var debugMode = false
 
 // --- Logging -----------------------------------------------------------------
@@ -454,132 +456,6 @@ func (fd *floodDetector) check() bool {
 	return count <= fd.limit
 }
 
-// --- IRC protocol ------------------------------------------------------------
-
-func ircToLower(c byte) byte {
-	switch c {
-	case '[':
-		return '{'
-	case ']':
-		return '}'
-	case '\\':
-		return '|'
-	case '~':
-		return '^'
-	}
-	if c >= 'A' && c <= 'Z' {
-		return c + ('a' - 'A')
-	}
-	return c
-}
-
-func ircToUpper(c byte) byte {
-	switch c {
-	case '{':
-		return '['
-	case '}':
-		return ']'
-	case '|':
-		return '\\'
-	case '^':
-		return '~'
-	}
-	if c >= 'a' && c <= 'z' {
-		return c - ('a' - 'A')
-	}
-	return c
-}
-
-// Convert identifier to a canonical form for case-insensitive comparisons.
-// ircToUpper is used so that statically initialized maps can be in uppercase.
-func ircToCanon(ident string) string {
-	var canon []byte
-	for _, c := range []byte(ident) {
-		canon = append(canon, ircToUpper(c))
-	}
-	return string(canon)
-}
-
-func ircEqual(s1, s2 string) bool {
-	return ircToCanon(s1) == ircToCanon(s2)
-}
-
-func ircFnmatch(pattern string, s string) bool {
-	pattern, s = ircToCanon(pattern), ircToCanon(s)
-	// FIXME: This should not support [] ranges and handle '/' specially.
-	// We could translate the pattern to a regular expression.
-	matched, _ := filepath.Match(pattern, s)
-	return matched
-}
-
-var reMsg = regexp.MustCompile(
-	`^(?:@([^ ]*) +)?(?::([^! ]*)(?:!([^@]*)@([^ ]*))? +)?([^ ]+)(.*)?$`)
-var reArgs = regexp.MustCompile(`:.*| [^: ][^ ]*`)
-
-type message struct {
-	tags    map[string]string // IRC 3.2 message tags
-	nick    string            // optional nickname
-	user    string            // optional username
-	host    string            // optional hostname or IP address
-	command string            // command name
-	params  []string          // arguments
-}
-
-func ircUnescapeMessageTag(value string) string {
-	var buf []byte
-	escape := false
-	for i := 0; i < len(value); i++ {
-		if escape {
-			switch value[i] {
-			case ':':
-				buf = append(buf, ';')
-			case 's':
-				buf = append(buf, ' ')
-			case 'r':
-				buf = append(buf, '\r')
-			case 'n':
-				buf = append(buf, '\n')
-			default:
-				buf = append(buf, value[i])
-			}
-			escape = false
-		} else if value[i] == '\\' {
-			escape = true
-		} else {
-			buf = append(buf, value[i])
-		}
-	}
-	return string(buf)
-}
-
-func ircParseMessageTags(tags string, out map[string]string) {
-	for _, tag := range splitString(tags, ";", true /* ignoreEmpty */) {
-		if equal := strings.IndexByte(tag, '='); equal < 0 {
-			out[tag] = ""
-		} else {
-			out[tag[:equal]] = ircUnescapeMessageTag(tag[equal+1:])
-		}
-	}
-}
-
-func ircParseMessage(line string) *message {
-	m := reMsg.FindStringSubmatch(line)
-	if m == nil {
-		return nil
-	}
-
-	msg := message{nil, m[2], m[3], m[4], m[5], nil}
-	if m[1] != "" {
-		msg.tags = make(map[string]string)
-		ircParseMessageTags(m[1], msg.tags)
-	}
-	for _, x := range reArgs.FindAllString(m[6], -1) {
-		msg.params = append(msg.params, x[1:])
-	}
-	return &msg
-
-}
-
 // --- IRC token validation ----------------------------------------------------
 
 // Everything as per RFC 2812

xW/.clang-format

@@ -0,0 +1,11 @@
+BasedOnStyle: LLVM
+ColumnLimit: 80
+IndentWidth: 4
+TabWidth: 4
+UseTab: ForContinuationAndIndentation
+AlwaysBreakAfterReturnType: AllDefinitions
+BreakBeforeBraces: Linux
+SpaceAfterCStyleCast: true
+AlignAfterOpenBracket: DontAlign
+AlignOperands: DontAlign
+SpacesBeforeTrailingComments: 2

xW/CMakeLists.txt

@@ -0,0 +1,85 @@
+# The last version with Windows XP support is 3.13, we want to keep that
+cmake_minimum_required (VERSION 3.10)
+
+file (READ ../xK-version project_version)
+configure_file (../xK-version xK-version.tag COPYONLY)
+string (STRIP "${project_version}" project_version)
+
+# This is an entirely separate CMake project--the main executables only build
+# on Windows within Cygwin, and this Windows executable only builds on Linux
+# cross-compiled, so you'd want to build them independently anyway.
+project (xW VERSION "${project_version}"
+	DESCRIPTION "Win32 frontend for xC" LANGUAGES CXX)
+
+set (CMAKE_CXX_STANDARD 17)
+
+add_definitions (-DUNICODE -D_UNICODE)
+add_compile_options ("$<$<CXX_COMPILER_ID:MSVC>:/utf-8>")
+add_compile_options ("$<$<CXX_COMPILER_ID:GNU>:-Wall;-Wextra>")
+add_compile_options ("$<$<CXX_COMPILER_ID:Clang>:-Wall;-Wextra>")
+add_link_options ("$<$<CXX_COMPILER_ID:GNU>:-static;-municode>")
+add_link_options ("$<$<CXX_COMPILER_ID:Clang>:-static;-municode>")
+
+set (project_config ${PROJECT_BINARY_DIR}/config.h)
+configure_file (${PROJECT_SOURCE_DIR}/config.h.in ${project_config})
+include_directories (${PROJECT_SOURCE_DIR} ${PROJECT_BINARY_DIR})
+
+# Produce a beep sample
+if (NOT ${CMAKE_VERSION} VERSION_LESS 3.18.0)
+	set (find_program_REQUIRE REQUIRED)
+endif ()
+
+find_program (sox_EXECUTABLE sox ${find_program_REQUIRE})
+add_custom_command (OUTPUT beep.wav
+	COMMAND ${sox_EXECUTABLE} -b 16 -Dr 44100 -n beep.wav
+		synth 0.1 0 25 triangle 800 vol 0.5 fade t 0 -0 0.005 pad 0 0.05
+	COMMENT "Generating a beep sample" VERBATIM)
+
+# Rasterize SVG icons
+set (root "${PROJECT_SOURCE_DIR}/..")
+set (CMAKE_MODULE_PATH ${root}/liberty/cmake)
+include (IconUtils)
+
+set (icon_ico_list)
+foreach (icon xW xW-highlighted)
+	set (icon_png_list)
+	foreach (icon_size 16 32 48)
+		icon_to_png (${icon} ${PROJECT_SOURCE_DIR}/${icon}.svg
+			${icon_size} ${PROJECT_BINARY_DIR}/icons icon_png)
+		list (APPEND icon_png_list ${icon_png})
+	endforeach ()
+	icon_to_png (${icon} ${PROJECT_SOURCE_DIR}/${icon}.svg
+		256 ${PROJECT_BINARY_DIR}/icons icon_png)
+
+	set (icon_ico ${PROJECT_BINARY_DIR}/${icon}.ico)
+	icon_for_win32 (${icon_ico} "${icon_png_list}" "${icon_png}")
+	list (APPEND icon_ico_list ${icon_ico})
+endforeach ()
+
+set_property (SOURCE xW.rc
+	APPEND PROPERTY OBJECT_DEPENDS ${icon_ico_list} beep.wav)
+
+# Build the main executable and link it
+find_program (awk_EXECUTABLE awk ${find_program_REQUIRE})
+add_custom_command (OUTPUT xC-proto.cpp
+	COMMAND ${CMAKE_COMMAND} -E env LC_ALL=C ${awk_EXECUTABLE}
+		-f ${root}/liberty/tools/lxdrgen.awk
+		-f ${root}/liberty/tools/lxdrgen-cpp.awk
+		-v PrefixCamel=Relay
+		${root}/xC.lxdr > xC-proto.cpp
+	DEPENDS
+		${root}/liberty/tools/lxdrgen.awk
+		${root}/liberty/tools/lxdrgen-cpp.awk
+		${root}/xC.lxdr
+	COMMENT "Generating xC relay protocol code" VERBATIM)
+add_custom_target (xC-proto DEPENDS ${PROJECT_BINARY_DIR}/xC-proto.cpp)
+
+add_executable (xW WIN32 xW.cpp xW.rc xW.manifest ${project_config}
+	${root}/liberty/tools/lxdrgen-cpp-win32.cpp)
+target_link_libraries (xW comctl32 ws2_32 winmm)
+add_dependencies (xW xC-proto)
+
+# At least with MinGW, this is a fully independent portable executable
+install (TARGETS xW DESTINATION .)
+set (CPACK_GENERATOR ZIP)
+include (CPack)

xW/config.h.in

@@ -0,0 +1,14 @@
+#ifndef CONFIG_H
+#define CONFIG_H
+
+#define PROJECT_NAME        "${PROJECT_NAME}"
+#define PROJECT_VERSION     "${project_version}"
+#define PROJECT_DESCRIPTION "${PROJECT_DESCRIPTION}"
+#define PROJECT_AUTHOR      "Přemysl Eric Janouch"
+
+#define PROJECT_MAJOR       (${PROJECT_VERSION_MAJOR}-0)
+#define PROJECT_MINOR       (${PROJECT_VERSION_MINOR}-0)
+#define PROJECT_PATCH       (${PROJECT_VERSION_PATCH}-0)
+#define PROJECT_TWEAK       (${PROJECT_VERSION_TWEAK}-0)
+
+#endif  // ! CONFIG_H

xW/xW-highlighted.svg

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg version="1.1" width="48" height="48" viewBox="0 0 48 48"
+   xmlns="http://www.w3.org/2000/svg">
+
+  <defs>
+    <clipPath id="outer">
+      <rect x="-1" y="-0.15" width="5" height="3.30" />
+    </clipPath>
+    <clipPath id="inner">
+      <rect x="-1" y="0" width="5" height="3" />
+    </clipPath>
+  </defs>
+
+  <g transform="translate(6, 6) scale(12)" stroke-linecap="square">
+    <g clip-path="url(#outer)">
+      <path stroke="#ffffff" stroke-width="1.5" d="M 0.5,0 2.5,3" />
+      <path stroke="#ffffff" stroke-width="1.5" d="M 0.5,3 2.5,0" />
+    </g>
+    <g clip-path="url(#inner)">
+      <path stroke="#ff0000" stroke-width="0.9" d="M 0.5,0 2.5,3" />
+      <path stroke="#ff0000" stroke-width="0.9" d="M 0.5,3 2.5,0" />
+    </g>
+  </g>
+</svg>

xW/xW-resources.h

@@ -0,0 +1,18 @@
+#define IDI_ICON                1
+#define IDI_HIGHLIGHTED         2
+#define IDR_BEEP                3
+#define IDA_ACCELERATORS       10
+
+// Named after input_add_functions() in xC.
+#define ID_PREVIOUS_BUFFER     11
+#define ID_NEXT_BUFFER         12
+#define ID_SWITCH_BUFFER       13
+#define ID_GOTO_HIGHLIGHT      14
+#define ID_GOTO_ACTIVITY       15
+#define ID_TOGGLE_UNIMPORTANT  16
+#define ID_DISPLAY_FULL_LOG    17
+
+#define IDD_CONNECT            20
+#define IDC_STATIC             21
+#define IDC_HOST               22
+#define IDC_PORT               23

xW/xW.manifest

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
+	<assemblyIdentity name="xW" version="1.0.0.0" type="win32" />
+	<dependency>
+		<dependentAssembly>
+			<assemblyIdentity name="Microsoft.Windows.Common-Controls"
+				version="6.0.0.0" type="win32" processorArchitecture="*"
+				publicKeyToken="6595b64144ccf1df" language="*" />
+		</dependentAssembly>
+	</dependency>
+	<compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
+		<application>
+			<!-- Windows 10 -->
+			<supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}" />
+			<!-- Windows 8.1 -->
+			<supportedOS Id="{1f676c76-80e1-4239-95bb-83d0f6d0da78}" />
+			<!-- Windows 8 -->
+			<supportedOS Id="{4a2f28e3-53b9-4441-ba9c-d69d4a4a6e38}" />
+			<!-- Windows 7 -->
+			<supportedOS Id="{35138b9a-5d96-4fbd-8e2d-a2440225f93a}" />
+			<!-- Windows Vista -->
+			<supportedOS Id="{e2011457-1546-43c5-a5fe-008deee3d3f0}" />
+		</application>
+	</compatibility>
+</assembly>

xW/xW.rc

@@ -0,0 +1,80 @@
+#include <windows.h>
+#include "xW-resources.h"
+
+// https://devblogs.microsoft.com/oldnewthing/20190607-00/?p=102569
+// For UTF-8 literals to work in both MinGW and Microsoft resource compilers,
+// the pragma needs to be in this file, and before they're included.
+#pragma code_page(65001)
+#include "config.h"
+
+// Beware of this madness https://gitlab.kitware.com/cmake/cmake/-/issues/23066
+CREATEPROCESS_MANIFEST_RESOURCE_ID RT_MANIFEST "xW.manifest"
+
+IDI_ICON ICON "xW.ico"
+IDI_HIGHLIGHTED ICON "xW-highlighted.ico"
+IDR_BEEP WAVE "beep.wav"
+
+IDA_ACCELERATORS ACCELERATORS
+BEGIN
+	"^p",     ID_PREVIOUS_BUFFER
+	"^n",     ID_NEXT_BUFFER
+	VK_F5,    ID_PREVIOUS_BUFFER,             VIRTKEY
+	VK_F6,    ID_NEXT_BUFFER,                 VIRTKEY
+	VK_PRIOR, ID_PREVIOUS_BUFFER,    CONTROL, VIRTKEY
+	VK_NEXT,  ID_NEXT_BUFFER,        CONTROL, VIRTKEY
+	VK_TAB,   ID_SWITCH_BUFFER,      CONTROL, VIRTKEY
+	// These are proper, but llvm-rc won't accept them (GitHub #64002).
+#ifndef __clang__
+	"!",      ID_GOTO_HIGHLIGHT,     ALT
+	"a",      ID_GOTO_ACTIVITY,      ALT
+	"H",      ID_TOGGLE_UNIMPORTANT, ALT
+	"h",      ID_DISPLAY_FULL_LOG,   ALT
+#endif
+END
+
+// https://devblogs.microsoft.com/oldnewthing/20050204-00/?p=36523
+// https://devblogs.microsoft.com/oldnewthing/20050207-00/?p=36513
+//
+// Note that this is still not the right font to use in newest Windows,
+// that would be 9pt Segoe UI, as described in:
+// https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts
+// or even better yet, NONCLIENTMETRICS::lfMessageFont.
+IDD_CONNECT DIALOGEX 0, 0, 150, 64
+STYLE DS_SHELLFONT | DS_MODALFRAME | DS_CENTER \
+	| WS_POPUP | WS_CAPTION | WS_SYSMENU
+CAPTION "Connect to Relay"
+FONT 8, "MS Shell Dlg", 400 /*FW_NORMAL*/, 0 /*FALSE*/, 0x1 /*DEFAULT_CHARSET*/
+BEGIN
+	LTEXT         "&Host:",   IDC_STATIC, 7, 10,  18,  8
+	EDITTEXT                  IDC_HOST,  39,  7, 104, 14, ES_AUTOHSCROLL
+	LTEXT         "&Port:",   IDC_STATIC, 7, 28,  18,  8
+	EDITTEXT                  IDC_PORT,  39, 25, 104, 14, ES_AUTOHSCROLL
+	DEFPUSHBUTTON "&Connect", IDOK,      39, 43,  50, 14
+	PUSHBUTTON    "E&xit",    IDCANCEL,  93, 43,  50, 14
+END
+
+VS_VERSION_INFO VERSIONINFO
+FILEVERSION     PROJECT_MAJOR, PROJECT_MINOR, PROJECT_PATCH, PROJECT_TWEAK
+PRODUCTVERSION  PROJECT_MAJOR, PROJECT_MINOR, PROJECT_PATCH, PROJECT_TWEAK
+FILETYPE        VFT_APP
+BEGIN
+	BLOCK "StringFileInfo"
+	BEGIN
+		BLOCK "040904B0"
+		BEGIN
+			VALUE "CompanyName",      PROJECT_AUTHOR
+			VALUE "FileDescription",  PROJECT_DESCRIPTION
+			VALUE "FileVersion",      PROJECT_VERSION
+			VALUE "InternalName",     PROJECT_NAME
+			VALUE "LegalCopyright",   PROJECT_AUTHOR
+			VALUE "OriginalFilename", PROJECT_NAME ".exe"
+			VALUE "ProductName",      PROJECT_NAME
+			VALUE "ProductVersion",   PROJECT_VERSION
+		END
+	END
+
+	BLOCK "VarFileInfo"
+	BEGIN
+		VALUE "Translation", 0x409, 1200
+	END
+END

xW/xW.svg

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg version="1.1" width="48" height="48" viewBox="0 0 48 48"
+   xmlns="http://www.w3.org/2000/svg">
+
+  <defs>
+    <clipPath id="outer">
+      <rect x="-1" y="-0.15" width="5" height="3.30" />
+    </clipPath>
+    <clipPath id="inner">
+      <rect x="-1" y="0" width="5" height="3" />
+    </clipPath>
+  </defs>
+
+  <g transform="translate(6, 6) scale(12)" stroke-linecap="square">
+    <g clip-path="url(#outer)">
+      <path stroke="#ffffff" stroke-width="1.5" d="M 0.5,0 2.5,3" />
+      <path stroke="#ffffff" stroke-width="1.5" d="M 0.5,3 2.5,0" />
+    </g>
+    <g clip-path="url(#inner)">
+      <path stroke="#000000" stroke-width="0.2" d="M 0,0 2,3 M 1,0 3,3" />
+      <path stroke="#ff6600" stroke-width="0.3" d="M 0,3 2,0 M 1,3 3,0" />
+    </g>
+  </g>
+</svg>