WIP: add a stub IRC daemon named `kike'

As it is going to share a great lot of functionality with ZyklonB, I have
decided to extract the common parts into `common.c' and make the two subprojects
include this file.

The Single Compile Unit concept has proven valuable (sub-second compile times,
dead code warnings, almost no need for function declarations, whole-program
optimizations), and the sources aren't that long so far anyway.

I am probably going to add CMake support later but so far it's not a priority.
This project is meant to be portable and freely relocatable (ie. no hardcoded
paths if I can avoid it).

5 files changed, 2654 insertions, 1609 deletions

diff --git a/Makefile b/Makefile
index f47959a..db6d657 100644
--- a/Makefile
+++ b/Makefile
@@ -1,17 +1,20 @@
 SHELL = /bin/sh
 CC = clang
 CFLAGS = -ggdb -Wall -Wextra -std=c99
-LDFLAGS = `pkg-config --libs libssl`
+# -lpthread is only there for debugging (gdb & errno)
+LDFLAGS = `pkg-config --libs libssl` -lpthread
 
 .PHONY: all clean
 
-targets = zyklonb
+targets = zyklonb kike
 
 all: $(targets)
 
 clean:
 	rm -f $(targets)
 
-zyklonb: src/zyklonb.c src/siphash.c
-	$(CC) $^ -o $@ $(CFLAGS) $(LDFLAGS)
+zyklonb: src/zyklonb.c src/common.c src/siphash.c
+	$(CC) src/zyklonb.c src/siphash.c -o $@ $(CFLAGS) $(LDFLAGS)
+kike: src/kike.c src/common.c src/siphash.c
+	$(CC) src/kike.c src/siphash.c -o $@ $(CFLAGS) $(LDFLAGS)
 
diff --git a/README b/README
index d00bd27..e036f87 100644
--- a/README
+++ b/README
@@ -10,6 +10,17 @@ While originally intended to be a simple C99 rewrite of the original bot, which
 was written in the GNU dialect of AWK, it fairly quickly became a playground
 where I added everything that seemed nice.
 
+kike
+----
+Also included is a simple IRC daemon that mostly follows the RFC's but is
+limited to single-server networks, due to the protocol being incredibly ugly
+and tricky to implement correctly.  Even so, it took me a ridiculous amount of
+time to write.  (But it was a valuable exercise and I can reuse the code.)
+
+Disclaimer
+----------
+I am not an antisemitist, I'm just being an offensive asshole with the naming.
+
 License
 -------
 `ZyklonB' is written by Přemysl Janouch <p.janouch@gmail.com>.
diff --git a/src/common.c b/src/common.c
new file mode 100644
index 0000000..be523a9
--- /dev/null
+++ b/src/common.c
@@ -0,0 +1,1772 @@
+/*
+ * common.c: common functionality
+ *
+ * Copyright (c) 2014, Přemysl Janouch <p.janouch@gmail.com>
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * 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.
+ *
+ */
+
+#define _POSIX_C_SOURCE 199309L
+#define _XOPEN_SOURCE 500
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <ctype.h>
+#include <time.h>
+#include <limits.h>
+
+#include <unistd.h>
+#include <sys/wait.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <fcntl.h>
+#include <poll.h>
+#include <signal.h>
+#include <strings.h>
+#include <regex.h>
+#include <libgen.h>
+
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <netdb.h>
+
+#ifndef NI_MAXHOST
+#define NI_MAXHOST 1025
+#endif // ! NI_MAXHOST
+
+#ifndef NI_MAXSERV
+#define NI_MAXSERV 32
+#endif // ! NI_MAXSERV
+
+#include <getopt.h>
+#include <openssl/ssl.h>
+#include <openssl/err.h>
+#include "siphash.h"
+
+extern char **environ;
+
+#ifdef _POSIX_MONOTONIC_CLOCK
+#define CLOCK_BEST CLOCK_MONOTONIC
+#else // ! _POSIX_MONOTIC_CLOCK
+#define CLOCK_BEST CLOCK_REALTIME
+#endif // ! _POSIX_MONOTONIC_CLOCK
+
+#if defined __GNUC__
+#define ATTRIBUTE_PRINTF(x, y) __attribute__ ((format (printf, x, y)))
+#else // ! __GNUC__
+#define ATTRIBUTE_PRINTF(x, y)
+#endif // ! __GNUC__
+
+#if defined __GNUC__ && __GNUC__ >= 4
+#define ATTRIBUTE_SENTINEL __attribute__ ((sentinel))
+#else // ! __GNUC__ || __GNUC__ < 4
+#define ATTRIBUTE_SENTINEL
+#endif // ! __GNUC__ || __GNUC__ < 4
+
+#define N_ELEMENTS(a) (sizeof (a) / sizeof ((a)[0]))
+
+#define BLOCK_START  do {
+#define BLOCK_END    } while (0)
+
+// --- Utilities ---------------------------------------------------------------
+
+static void
+print_message (FILE *stream, const char *type, const char *fmt, ...)
+	ATTRIBUTE_PRINTF (3, 4);
+
+static void
+print_message (FILE *stream, const char *type, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start (ap, fmt);
+	fprintf (stream, "%s ", type);
+	vfprintf (stream, fmt, ap);
+	fputs ("\n", stream);
+	va_end (ap);
+}
+
+#define print_fatal(...)    print_message (stderr, "fatal:",   __VA_ARGS__)
+#define print_error(...)    print_message (stderr, "error:",   __VA_ARGS__)
+#define print_warning(...)  print_message (stderr, "warning:", __VA_ARGS__)
+#define print_status(...)   print_message (stdout, "--",       __VA_ARGS__)
+
+// --- Debugging and assertions ------------------------------------------------
+
+// We should check everything that may possibly fail with at least a soft
+// assertion, so that any causes for problems don't slip us by silently.
+//
+// `g_soft_asserts_are_deadly' may be useful while running inside a debugger.
+
+static bool g_debug_mode;               ///< Debug messages are printed
+static bool g_soft_asserts_are_deadly;  ///< soft_assert() aborts as well
+
+#define print_debug(...)                                                       \
+	BLOCK_START                                                                \
+		if (g_debug_mode)                                                      \
+			print_message (stderr, "debug:", __VA_ARGS__);                     \
+	BLOCK_END
+
+static void
+assertion_failure_handler (bool is_fatal, const char *file, int line,
+	const char *function, const char *condition)
+{
+	if (is_fatal)
+	{
+		print_fatal ("assertion failed [%s:%d in function %s]: %s",
+			file, line, function, condition);
+		abort ();
+	}
+	else
+		print_debug ("assertion failed [%s:%d in function %s]: %s",
+			file, line, function, condition);
+}
+
+#define soft_assert(condition)                                                 \
+	((condition) ? true :                                                      \
+		(assertion_failure_handler (g_soft_asserts_are_deadly,                 \
+		__FILE__, __LINE__, __func__, #condition), false))
+
+#define hard_assert(condition)                                                 \
+	((condition) ? (void) 0 :                                                  \
+		assertion_failure_handler (true,                                       \
+		__FILE__, __LINE__, __func__, #condition))
+
+// --- Safe memory management --------------------------------------------------
+
+// When a memory allocation fails and we need the memory, we're usually pretty
+// much fucked.  Use the non-prefixed versions when there's a legitimate
+// worry that an unrealistic amount of memory may be requested for allocation.
+
+// XXX: it's not a good idea to use print_message() as it may want to allocate
+//   further memory for printf() and the output streams.  That may fail.
+
+static void *
+xmalloc (size_t n)
+{
+	void *p = malloc (n);
+	if (!p)
+	{
+		print_fatal ("malloc: %s", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+	return p;
+}
+
+static void *
+xcalloc (size_t n, size_t m)
+{
+	void *p = calloc (n, m);
+	if (!p && n && m)
+	{
+		print_fatal ("calloc: %s", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+	return p;
+}
+
+static void *
+xrealloc (void *o, size_t n)
+{
+	void *p = realloc (o, n);
+	if (!p && n)
+	{
+		print_fatal ("realloc: %s", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+	return p;
+}
+
+static void *
+xreallocarray (void *o, size_t n, size_t m)
+{
+	if (m && n > SIZE_MAX / m)
+	{
+		errno = ENOMEM;
+		print_fatal ("reallocarray: %s", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+	return xrealloc (o, n * m);
+}
+
+static char *
+xstrdup (const char *s)
+{
+	return strcpy (xmalloc (strlen (s) + 1), s);
+}
+
+static char *
+xstrndup (const char *s, size_t n)
+{
+	size_t size = strlen (s);
+	if (n > size)
+		n = size;
+
+	char *copy = xmalloc (n + 1);
+	memcpy (copy, s, n);
+	copy[n] = '\0';
+	return copy;
+}
+
+// --- Double-linked list helpers ----------------------------------------------
+
+// The links of the list need to have the members `prev' and `next'.
+
+#define LIST_PREPEND(head, link)                                               \
+	BLOCK_START                                                                \
+		(link)->prev = NULL;                                                   \
+		(link)->next = (head);                                                 \
+		if ((link)->next)                                                      \
+			(link)->next->prev = (link);                                       \
+		(head) = (link);                                                       \
+	BLOCK_END
+
+#define LIST_UNLINK(head, link)                                                \
+	BLOCK_START                                                                \
+		if ((link)->prev)                                                      \
+			(link)->prev->next = (link)->next;                                 \
+		else                                                                   \
+			(head) = (link)->next;                                             \
+		if ((link)->next)                                                      \
+			(link)->next->prev = (link)->prev;                                 \
+	BLOCK_END
+
+// --- Dynamically allocated string array --------------------------------------
+
+struct str_vector
+{
+	char **vector;
+	size_t len;
+	size_t alloc;
+};
+
+static void
+str_vector_init (struct str_vector *self)
+{
+	self->alloc = 4;
+	self->len = 0;
+	self->vector = xcalloc (sizeof *self->vector, self->alloc);
+}
+
+static void
+str_vector_free (struct str_vector *self)
+{
+	unsigned i;
+	for (i = 0; i < self->len; i++)
+		free (self->vector[i]);
+
+	free (self->vector);
+	self->vector = NULL;
+}
+
+static void
+str_vector_add_owned (struct str_vector *self, char *s)
+{
+	self->vector[self->len] = s;
+	if (++self->len >= self->alloc)
+		self->vector = xreallocarray (self->vector,
+			sizeof *self->vector, (self->alloc <<= 1));
+	self->vector[self->len] = NULL;
+}
+
+static void
+str_vector_add (struct str_vector *self, const char *s)
+{
+	str_vector_add_owned (self, xstrdup (s));
+}
+
+static void
+str_vector_add_args (struct str_vector *self, const char *s, ...)
+	ATTRIBUTE_SENTINEL;
+
+static void
+str_vector_add_args (struct str_vector *self, const char *s, ...)
+{
+	va_list ap;
+
+	va_start (ap, s);
+	while (s)
+	{
+		str_vector_add (self, s);
+		s = va_arg (ap, const char *);
+	}
+	va_end (ap);
+}
+
+static void
+str_vector_add_vector (struct str_vector *self, char **vector)
+{
+	while (*vector)
+		str_vector_add (self, *vector++);
+}
+
+static void
+str_vector_remove (struct str_vector *self, size_t i)
+{
+	hard_assert (i < self->len);
+	free (self->vector[i]);
+	memmove (self->vector + i, self->vector + i + 1,
+		(self->len-- - i) * sizeof *self->vector);
+}
+
+// --- Dynamically allocated strings -------------------------------------------
+
+// Basically a string builder to abstract away manual memory management.
+
+struct str
+{
+	char *str;                          ///< String data, null terminated
+	size_t alloc;                       ///< How many bytes are allocated
+	size_t len;                         ///< How long the string actually is
+};
+
+/// We don't care about allocations that are way too large for the content, as
+/// long as the allocation is below the given threshold.  (Trivial heuristics.)
+#define STR_SHRINK_THRESHOLD (1 << 20)
+
+static void
+str_init (struct str *self)
+{
+	self->alloc = 16;
+	self->len = 0;
+	self->str = strcpy (xmalloc (self->alloc), "");
+}
+
+static void
+str_free (struct str *self)
+{
+	free (self->str);
+	self->str = NULL;
+	self->alloc = 0;
+	self->len = 0;
+}
+
+static void
+str_reset (struct str *self)
+{
+	str_free (self);
+	str_init (self);
+}
+
+static char *
+str_steal (struct str *self)
+{
+	char *str = self->str;
+	self->str = NULL;
+	str_free (self);
+	return str;
+}
+
+static void
+str_ensure_space (struct str *self, size_t n)
+{
+	// We allocate at least one more byte for the terminating null character
+	size_t new_alloc = self->alloc;
+	while (new_alloc <= self->len + n)
+		new_alloc <<= 1;
+	if (new_alloc != self->alloc)
+		self->str = xrealloc (self->str, (self->alloc = new_alloc));
+}
+
+static void
+str_append_data (struct str *self, const char *data, size_t n)
+{
+	str_ensure_space (self, n);
+	memcpy (self->str + self->len, data, n);
+	self->len += n;
+	self->str[self->len] = '\0';
+}
+
+static void
+str_append_c (struct str *self, char c)
+{
+	str_append_data (self, &c, 1);
+}
+
+static void
+str_append (struct str *self, const char *s)
+{
+	str_append_data (self, s, strlen (s));
+}
+
+static void
+str_append_str (struct str *self, const struct str *another)
+{
+	str_append_data (self, another->str, another->len);
+}
+
+static int
+str_append_vprintf (struct str *self, const char *fmt, va_list va)
+{
+	va_list ap;
+	int size;
+
+	va_copy (ap, va);
+	size = vsnprintf (NULL, 0, fmt, ap);
+	va_end (ap);
+
+	if (size < 0)
+		return -1;
+
+	va_copy (ap, va);
+	str_ensure_space (self, size);
+	size = vsnprintf (self->str + self->len, self->alloc - self->len, fmt, ap);
+	va_end (ap);
+
+	if (size > 0)
+		self->len += size;
+
+	return size;
+}
+
+static int
+str_append_printf (struct str *self, const char *fmt, ...)
+	ATTRIBUTE_PRINTF (2, 3);
+
+static int
+str_append_printf (struct str *self, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start (ap, fmt);
+	int size = str_append_vprintf (self, fmt, ap);
+	va_end (ap);
+	return size;
+}
+
+static void
+str_remove_slice (struct str *self, size_t start, size_t length)
+{
+	size_t end = start + length;
+	hard_assert (end <= self->len);
+	memmove (self->str + start, self->str + end, self->len - end);
+	self->str[self->len -= length] = '\0';
+
+	// Shrink the string if the allocation becomes way too large
+	if (self->alloc >= STR_SHRINK_THRESHOLD && self->len < (self->alloc >> 2))
+		self->str = xrealloc (self->str, self->alloc >>= 2);
+}
+
+// --- Errors ------------------------------------------------------------------
+
+// Error reporting utilities.  Inspired by GError, only much simpler.
+
+struct error
+{
+	size_t domain;                      ///< The domain of the error
+	int id;                             ///< The concrete error ID
+	char *message;                      ///< Textual description of the event
+};
+
+static size_t
+error_resolve_domain (size_t *tag)
+{
+	// This method is fairly sensitive to the order in which resolution
+	// requests come in, does not provide a good way of decoding the number
+	// back to a meaningful identifier, and may not play all too well with
+	// dynamic libraries when a module is e.g. statically linked into multiple
+	// libraries, but it's fast, simple, and more than enough for our purposes.
+	static size_t domain_counter;
+
+	if (!*tag)
+		*tag = ++domain_counter;
+	return *tag;
+}
+
+static void
+error_set (struct error **e, size_t domain, int id,
+	const char *message, ...) ATTRIBUTE_PRINTF (4, 5);
+
+static void
+error_set (struct error **e, size_t domain, int id,
+	const char *message, ...)
+{
+	if (!e)
+		return;
+
+	va_list ap;
+	va_start (ap, message);
+	int size = snprintf (NULL, 0, message, ap);
+	va_end (ap);
+
+	hard_assert (size >= 0);
+
+	struct error *tmp = xmalloc (sizeof *tmp);
+	tmp->domain = domain;
+	tmp->id = id;
+	tmp->message = xmalloc (size + 1);
+
+	va_start (ap, message);
+	size = snprintf (tmp->message, size + 1, message, ap);
+	va_end (ap);
+
+	hard_assert (size >= 0);
+
+	soft_assert (*e == NULL);
+	*e = tmp;
+}
+
+static void
+error_free (struct error *e)
+{
+	free (e->message);
+	free (e);
+}
+
+static void
+error_propagate (struct error **destination, struct error *source)
+{
+	if (!destination)
+	{
+		error_free (source);
+		return;
+	}
+
+	soft_assert (*destination == NULL);
+	*destination = source;
+}
+
+// --- String hash map ---------------------------------------------------------
+
+// The most basic <string, managed pointer> map (or associative array).
+
+struct str_map_link
+{
+	struct str_map_link *next;          ///< The next link in a chain
+	struct str_map_link *prev;          ///< The previous link in a chain
+
+	void *data;                         ///< Payload
+	size_t key_length;                  ///< Length of the key without '\0'
+	char key[];                         ///< The key for this link
+};
+
+struct str_map
+{
+	struct str_map_link **map;          ///< The hash table data itself
+	size_t alloc;                       ///< Number of allocated entries
+	size_t len;                         ///< Number of entries in the table
+	void (*free) (void *);              ///< Callback to destruct the payload
+};
+
+#define STR_MAP_MIN_ALLOC 16
+
+typedef void (*str_map_free_func) (void *);
+
+static void
+str_map_init (struct str_map *self)
+{
+	self->alloc = STR_MAP_MIN_ALLOC;
+	self->len = 0;
+	self->free = NULL;
+	self->map = xcalloc (self->alloc, sizeof *self->map);
+}
+
+static void
+str_map_free (struct str_map *self)
+{
+	struct str_map_link **iter, **end = self->map + self->alloc;
+	struct str_map_link *link, *tmp;
+
+	for (iter = self->map; iter < end; iter++)
+		for (link = *iter; link; link = tmp)
+		{
+			tmp = link->next;
+			if (self->free)
+				self->free (link->data);
+			free (link);
+		}
+
+	free (self->map);
+	self->map = NULL;
+}
+
+static uint64_t
+str_map_hash (const char *s, size_t len)
+{
+	static unsigned char key[16] = "SipHash 2-4 key!";
+	return siphash (key, (const void *) s, len);
+}
+
+static uint64_t
+str_map_pos (struct str_map *self, const char *s)
+{
+	size_t mask = self->alloc - 1;
+	return str_map_hash (s, strlen (s)) & mask;
+}
+
+static uint64_t
+str_map_link_hash (struct str_map_link *self)
+{
+	return str_map_hash (self->key, self->key_length);
+}
+
+static void
+str_map_resize (struct str_map *self, size_t new_size)
+{
+	struct str_map_link **old_map = self->map;
+	size_t i, old_size = self->alloc;
+
+	// Only powers of two, so that we don't need to compute the modulo
+	hard_assert ((new_size & (new_size - 1)) == 0);
+	size_t mask = new_size - 1;
+
+	self->alloc = new_size;
+	self->map = xcalloc (self->alloc, sizeof *self->map);
+	for (i = 0; i < old_size; i++)
+	{
+		struct str_map_link *iter = old_map[i], *next_iter;
+		while (iter)
+		{
+			next_iter = iter->next;
+			uint64_t pos = str_map_link_hash (iter) & mask;
+			LIST_PREPEND (self->map[pos], iter);
+			iter = next_iter;
+		}
+	}
+
+	free (old_map);
+}
+
+static void
+str_map_set (struct str_map *self, const char *key, void *value)
+{
+	uint64_t pos = str_map_pos (self, key);
+	struct str_map_link *iter = self->map[pos];
+	for (; iter; iter = iter->next)
+	{
+		if (strcmp (key, iter->key))
+			continue;
+
+		// Storing the same data doesn't destroy it
+		if (self->free && value != iter->data)
+			self->free (iter->data);
+
+		if (value)
+		{
+			iter->data = value;
+			return;
+		}
+
+		LIST_UNLINK (self->map[pos], iter);
+		free (iter);
+		self->len--;
+
+		// The array should be at least 1/4 full
+		if (self->alloc >= (STR_MAP_MIN_ALLOC << 2)
+		 && self->len < (self->alloc >> 2))
+			str_map_resize (self, self->alloc >> 2);
+		return;
+	}
+
+	if (!value)
+		return;
+
+	if (self->len >= self->alloc)
+	{
+		str_map_resize (self, self->alloc << 1);
+		pos = str_map_pos (self, key);
+	}
+
+	// Link in a new element for the given <key, value> pair
+	size_t key_length = strlen (key);
+	struct str_map_link *link = xmalloc (sizeof *link + key_length + 1);
+	link->data = value;
+	link->key_length = key_length;
+	memcpy (link->key, key, key_length + 1);
+
+	LIST_PREPEND (self->map[pos], link);
+	self->len++;
+}
+
+static void *
+str_map_find (struct str_map *self, const char *key)
+{
+	struct str_map_link *iter = self->map[str_map_pos (self, key)];
+	for (; iter; iter = iter->next)
+		if (!strcmp (key, (char *) iter + sizeof *iter))
+			return iter->data;
+	return NULL;
+}
+
+// --- File descriptor utilities -----------------------------------------------
+
+static void
+set_cloexec (int fd)
+{
+	soft_assert (fcntl (fd, F_SETFD, fcntl (fd, F_GETFD) | FD_CLOEXEC) != -1);
+}
+
+static bool
+set_blocking (int fd, bool blocking)
+{
+	int flags = fcntl (fd, F_GETFL);
+	hard_assert (flags != -1);
+
+	bool prev = !(flags & O_NONBLOCK);
+	if (blocking)
+		flags &= ~O_NONBLOCK;
+	else
+		flags |=  O_NONBLOCK;
+
+	hard_assert (fcntl (fd, F_SETFL, flags) != -1);
+	return prev;
+}
+
+static void
+xclose (int fd)
+{
+	while (close (fd) == -1)
+		if (!soft_assert (errno == EINTR))
+			break;
+}
+
+// --- Polling -----------------------------------------------------------------
+
+// Basically the poor man's GMainLoop/libev/libuv.  It might make some sense
+// to instead use those tested and proven libraries but we don't need much
+// and it's interesting to implement.
+
+// At the moment the FD's are stored in an unsorted array.  This is not ideal
+// complexity-wise but I don't think I have much of a choice with poll(),
+// and neither with epoll for that matter.
+//
+//                         unsorted array       sorted array
+//           search             O(n)       O(log n) [O(log log n)]
+//           insert by fd       O(n)                O(n)
+//           delete by fd       O(n)                O(n)
+//
+// Insertion in the unsorted array can be reduced to O(1) if I maintain a
+// bitmap of present FD's but that's still not a huge win.
+//
+// I don't expect this to be much of an issue, as there are typically not going
+// to be that many FD's to watch, and the linear approach is cache-friendly.
+
+typedef void (*poller_dispatcher_func) (const struct pollfd *, void *);
+typedef void (*poller_timer_func) (void *);
+
+#define POLLER_MIN_ALLOC 16
+
+struct poller_timer_info
+{
+	int64_t when;                       ///< When is the timer to expire
+	poller_timer_func dispatcher;       ///< Event dispatcher
+	void *user_data;                    ///< User data
+};
+
+struct poller_timers
+{
+	struct poller_timer_info *info;     ///< Min-heap of timers
+	size_t len;                         ///< Number of scheduled timers
+	size_t alloc;                       ///< Number of timers allocated
+};
+
+static void
+poller_timers_init (struct poller_timers *self)
+{
+	self->alloc = POLLER_MIN_ALLOC;
+	self->len = 0;
+	self->info = xmalloc (self->alloc * sizeof *self->info);
+}
+
+static void
+poller_timers_free (struct poller_timers *self)
+{
+	free (self->info);
+}
+
+static int64_t
+poller_timers_get_current_time (void)
+{
+#ifdef _POSIX_TIMERS
+	struct timespec tp;
+	hard_assert (clock_gettime (CLOCK_BEST, &tp) != -1);
+	return (int64_t) tp.tv_sec * 1000 + (int64_t) tp.tv_nsec / 1000000;
+#else
+	struct timeval tp;
+	gettimeofday (&tp, NULL);
+	return (int64_t) tp.tv_sec * 1000 + (int64_t) tp.tv_usec / 1000;
+#endif
+}
+
+static void
+poller_timers_heapify_down (struct poller_timers *self, size_t index)
+{
+	typedef struct poller_timer_info info_t;
+	info_t *end = self->info + self->len;
+
+	while (true)
+	{
+		info_t *parent = self->info + index;
+		info_t *left   = self->info + 2 * index + 1;
+		info_t *right  = self->info + 2 * index + 2;
+
+		info_t *largest = parent;
+		if (left  < end && left->when  > largest->when)
+			largest = left;
+		if (right < end && right->when > largest->when)
+			largest = right;
+		if (parent == largest)
+			break;
+
+		info_t tmp = *parent;
+		*parent = *largest;
+		*largest = tmp;
+
+		index = largest - self->info;
+	}
+}
+
+static void
+poller_timers_remove_at_index (struct poller_timers *self, size_t index)
+{
+	hard_assert (index < self->len);
+	if (index == --self->len)
+		return;
+
+	self->info[index] = self->info[self->len];
+	poller_timers_heapify_down (self, index);
+}
+
+static void
+poller_timers_dispatch (struct poller_timers *self)
+{
+	int64_t now = poller_timers_get_current_time ();
+	while (self->len && self->info->when <= now)
+	{
+		struct poller_timer_info info = *self->info;
+		poller_timers_remove_at_index (self, 0);
+		info.dispatcher (info.user_data);
+	}
+}
+
+static void
+poller_timers_heapify_up (struct poller_timers *self, size_t index)
+{
+	while (index != 0)
+	{
+		size_t parent = (index - 1) / 2;
+		if (self->info[parent].when <= self->info[index].when)
+			break;
+
+		struct poller_timer_info tmp = self->info[parent];
+		self->info[parent] = self->info[index];
+		self->info[index] = tmp;
+
+		index = parent;
+	}
+}
+
+static ssize_t
+poller_timers_find (struct poller_timers *self,
+	poller_timer_func dispatcher, void *data)
+{
+	// NOTE: there may be duplicates.
+	for (size_t i = 0; i < self->len; i++)
+		if (self->info[i].dispatcher == dispatcher
+		 && self->info[i].user_data == data)
+			return i;
+	return -1;
+}
+
+static void
+poller_timers_add (struct poller_timers *self,
+	poller_timer_func dispatcher, void *data, int timeout_ms)
+{
+	if (self->len == self->alloc)
+		self->info = xreallocarray (self->info,
+			self->alloc <<= 1, sizeof *self->info);
+
+	self->info[self->len] = (struct poller_timer_info) {
+		.when = poller_timers_get_current_time () + timeout_ms,
+		.dispatcher = dispatcher, .user_data = data };
+	poller_timers_heapify_up (self, self->len++);
+}
+
+static int
+poller_timers_get_poll_timeout (struct poller_timers *self)
+{
+	if (!self->len)
+		return -1;
+
+	int64_t timeout = self->info->when - poller_timers_get_current_time ();
+	return timeout >= 0 ? timeout : 0;
+}
+
+#ifdef __linux__
+
+// I don't really need this, I've basically implemented this just because I can.
+
+#include <sys/epoll.h>
+
+struct poller_info
+{
+	int fd;                             ///< Our file descriptor
+	uint32_t events;                    ///< The events we registered
+	poller_dispatcher_func dispatcher;  ///< Event dispatcher
+	void *user_data;                    ///< User data
+};
+
+struct poller
+{
+	int epoll_fd;                       ///< The epoll FD
+	struct poller_info **info;          ///< Information associated with each FD
+	struct epoll_event *revents;        ///< Output array for epoll_wait()
+	size_t len;                         ///< Number of polled descriptors
+	size_t alloc;                       ///< Number of entries allocated
+
+	struct poller_timers timers;        ///< Timeouts
+
+	/// Index of the element in `revents' that's about to be dispatched next.
+	int dispatch_next;
+
+	/// The total number of entries stored in `revents' by epoll_wait().
+	int dispatch_total;
+};
+
+static void
+poller_init (struct poller *self)
+{
+	self->epoll_fd = epoll_create (POLLER_MIN_ALLOC);
+	hard_assert (self->epoll_fd != -1);
+	set_cloexec (self->epoll_fd);
+
+	self->len = 0;
+	self->alloc = POLLER_MIN_ALLOC;
+	self->info = xcalloc (self->alloc, sizeof *self->info);
+	self->revents = xcalloc (self->alloc, sizeof *self->revents);
+
+	poller_timers_init (&self->timers);
+
+	self->dispatch_next = 0;
+	self->dispatch_total = 0;
+}
+
+static void
+poller_free (struct poller *self)
+{
+	for (size_t i = 0; i < self->len; i++)
+	{
+		struct poller_info *info = self->info[i];
+		hard_assert (epoll_ctl (self->epoll_fd,
+			EPOLL_CTL_DEL, info->fd, (void *) "") != -1);
+		free (info);
+	}
+
+	poller_timers_free (&self->timers);
+
+	xclose (self->epoll_fd);
+	free (self->info);
+	free (self->revents);
+}
+
+static ssize_t
+poller_find_by_fd (struct poller *self, int fd)
+{
+	for (size_t i = 0; i < self->len; i++)
+		if (self->info[i]->fd == fd)
+			return i;
+	return -1;
+}
+
+static void
+poller_ensure_space (struct poller *self)
+{
+	if (self->len < self->alloc)
+		return;
+
+	self->alloc <<= 1;
+	self->revents = xreallocarray
+		(self->revents, sizeof *self->revents, self->alloc);
+	self->info = xreallocarray
+		(self->info, sizeof *self->info, self->alloc);
+}
+
+static int
+poller_epoll_to_poll_events (int events)
+{
+	int result = 0;
+	if (events & EPOLLIN)   result |= POLLIN;
+	if (events & EPOLLOUT)  result |= POLLOUT;
+	if (events & EPOLLERR)  result |= POLLERR;
+	if (events & EPOLLHUP)  result |= POLLHUP;
+	if (events & EPOLLPRI)  result |= POLLPRI;
+	return result;
+}
+
+static uint32_t
+poller_poll_to_epoll_events (uint32_t events)
+{
+	uint32_t result = 0;
+	if (events & POLLIN)   result |= EPOLLIN;
+	if (events & POLLOUT)  result |= EPOLLOUT;
+	if (events & POLLERR)  result |= EPOLLERR;
+	if (events & POLLHUP)  result |= EPOLLHUP;
+	if (events & POLLPRI)  result |= EPOLLPRI;
+	return result;
+}
+
+static void
+poller_set (struct poller *self, int fd, short int events,
+	poller_dispatcher_func dispatcher, void *data)
+{
+	ssize_t index = poller_find_by_fd (self, fd);
+	bool modifying = true;
+	if (index == -1)
+	{
+		poller_ensure_space (self);
+		self->info[index = self->len++] = xcalloc (1, sizeof **self->info);
+		modifying = false;
+	}
+
+	struct poller_info *info = self->info[index];
+	info->fd = fd;
+	info->dispatcher = dispatcher;
+	info->user_data = data;
+
+	struct epoll_event event;
+	event.events = poller_poll_to_epoll_events (events);
+	event.data.ptr = info;
+	hard_assert (epoll_ctl (self->epoll_fd,
+		modifying ? EPOLL_CTL_MOD : EPOLL_CTL_ADD, fd, &event) != -1);
+}
+
+static void
+poller_remove_from_dispatch (struct poller *self,
+	const struct poller_info *info)
+{
+	if (!self->dispatch_total)
+		return;
+
+	int i;
+	for (i = self->dispatch_next; i < self->dispatch_total; i++)
+		if (self->revents[i].data.ptr == info)
+			break;
+	if (i == self->dispatch_total)
+		return;
+
+	if (i != --self->dispatch_total)
+		self->revents[i] = self->revents[self->dispatch_total];
+}
+
+static void
+poller_remove_at_index (struct poller *self, size_t index)
+{
+	hard_assert (index < self->len);
+	struct poller_info *info = self->info[index];
+
+	poller_remove_from_dispatch (self, info);
+	hard_assert (epoll_ctl (self->epoll_fd,
+		EPOLL_CTL_DEL, info->fd, (void *) "") != -1);
+
+	free (info);
+	if (index != --self->len)
+		self->info[index] = self->info[self->len];
+}
+
+static void
+poller_run (struct poller *self)
+{
+	// Not reentrant
+	hard_assert (!self->dispatch_total);
+
+	int n_fds;
+	do
+		n_fds = epoll_wait (self->epoll_fd, self->revents, self->len,
+			poller_timers_get_poll_timeout (&self->timers));
+	while (n_fds == -1 && errno == EINTR);
+
+	if (n_fds == -1)
+	{
+		print_fatal ("%s: %s", "epoll", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+
+	poller_timers_dispatch (&self->timers);
+
+	self->dispatch_next = 0;
+	self->dispatch_total = n_fds;
+
+	while (self->dispatch_next < self->dispatch_total)
+	{
+		struct epoll_event *revents = self->revents + self->dispatch_next;
+		struct poller_info *info = revents->data.ptr;
+
+		struct pollfd pfd;
+		pfd.fd = info->fd;
+		pfd.revents = poller_epoll_to_poll_events (revents->events);
+		pfd.events = poller_epoll_to_poll_events (info->events);
+
+		self->dispatch_next++;
+		info->dispatcher (&pfd, info->user_data);
+	}
+
+	self->dispatch_next = 0;
+	self->dispatch_total = 0;
+}
+
+#else  // !__linux__
+
+struct poller_info
+{
+	poller_dispatcher_func dispatcher;  ///< Event dispatcher
+	void *user_data;                    ///< User data
+};
+
+struct poller
+{
+	struct pollfd *fds;                 ///< Polled descriptors
+	struct poller_info *fds_info;       ///< Additional information for each FD
+	size_t len;                         ///< Number of polled descriptors
+	size_t alloc;                       ///< Number of entries allocated
+
+	struct poller_timers timers;        ///< Timers
+	int dispatch_next;                  ///< The next dispatched FD or -1
+};
+
+static void
+poller_init (struct poller *self)
+{
+	self->alloc = POLLER_MIN_ALLOC;
+	self->len = 0;
+	self->fds = xcalloc (self->alloc, sizeof *self->fds);
+	self->fds_info = xcalloc (self->alloc, sizeof *self->fds_info);
+	poller_timers_init (&self->timers);
+	self->dispatch_next = -1;
+}
+
+static void
+poller_free (struct poller *self)
+{
+	free (self->fds);
+	free (self->fds_info);
+	poller_timers_free (&self->timers);
+}
+
+static ssize_t
+poller_find_by_fd (struct poller *self, int fd)
+{
+	for (size_t i = 0; i < self->len; i++)
+		if (self->fds[i].fd == fd)
+			return i;
+	return -1;
+}
+
+static void
+poller_ensure_space (struct poller *self)
+{
+	if (self->len < self->alloc)
+		return;
+
+	self->alloc <<= 1;
+	self->fds = xreallocarray (self->fds, sizeof *self->fds, self->alloc);
+	self->fds_info = xreallocarray
+		(self->fds_info, sizeof *self->fds_info, self->alloc);
+}
+
+static void
+poller_set (struct poller *self, int fd, short int events,
+	poller_dispatcher_func dispatcher, void *data)
+{
+	ssize_t index = poller_find_by_fd (self, fd);
+	if (index == -1)
+	{
+		poller_ensure_space (self);
+		index = self->len++;
+	}
+
+	struct pollfd *new_entry = self->fds + index;
+	memset (new_entry, 0, sizeof *new_entry);
+	new_entry->fd = fd;
+	new_entry->events = events;
+
+	self->fds_info[self->len] = (struct poller_info) { dispatcher, data };
+}
+
+static void
+poller_remove_at_index (struct poller *self, size_t index)
+{
+	hard_assert (index < self->len);
+	if (index == --self->len)
+		return;
+
+	// Make sure that we don't disrupt the dispatch loop; kind of crude
+	if ((int) index < self->dispatch_next)
+	{
+		memmove (self->fds + index, self->fds + index + 1,
+			(self->len - index) * sizeof *self->fds);
+		memmove (self->fds_info + index, self->fds_info + index + 1,
+			(self->len - index) * sizeof *self->fds_info);
+		self->dispatch_next--;
+	}
+	else
+	{
+		self->fds[index]      = self->fds[self->len];
+		self->fds_info[index] = self->fds_info[self->len];
+	}
+}
+
+static void
+poller_run (struct poller *self)
+{
+	// Not reentrant
+	hard_assert (self->dispatch_next == -1);
+
+	int result;
+	do
+		result = poll (self->fds, self->len,
+			poller_timers_get_poll_timeout (&self->timers));
+	while (result == -1 && errno == EINTR);
+
+	if (result == -1)
+	{
+		print_fatal ("%s: %s", "poll", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+
+	poller_timers_dispatch (&self->timers);
+
+	for (int i = 0; i < (int) self->len; )
+	{
+		struct pollfd pfd = self->fds[i];
+		if (!pfd.revents)
+			continue;
+
+		struct poller_info *info = self->fds_info + i;
+		self->dispatch_next = ++i;
+		info->dispatcher (&pfd, info->user_data);
+		i = self->dispatch_next;
+	}
+
+	self->dispatch_next = -1;
+}
+
+#endif  // !__linux__
+
+// --- Utilities ---------------------------------------------------------------
+
+static void
+split_str_ignore_empty (const char *s, char delimiter, struct str_vector *out)
+{
+	const char *begin = s, *end;
+
+	while ((end = strchr (begin, delimiter)))
+	{
+		if (begin != end)
+			str_vector_add_owned (out, xstrndup (begin, end - begin));
+		begin = ++end;
+	}
+
+	if (*begin)
+		str_vector_add (out, begin);
+}
+
+static char *
+strip_str_in_place (char *s, const char *stripped_chars)
+{
+	char *end = s + strlen (s);
+	while (end > s && strchr (stripped_chars, end[-1]))
+		*--end = '\0';
+
+	char *start = s + strspn (s, stripped_chars);
+	if (start > s)
+		memmove (s, start, end - start + 1);
+	return s;
+}
+
+static bool
+str_append_env_path (struct str *output, const char *var, bool only_absolute)
+{
+	const char *value = getenv (var);
+
+	if (!value || (only_absolute && *value != '/'))
+		return false;
+
+	str_append (output, value);
+	return true;
+}
+
+static void
+get_xdg_home_dir (struct str *output, const char *var, const char *def)
+{
+	str_reset (output);
+	if (!str_append_env_path (output, var, true))
+	{
+		str_append_env_path (output, "HOME", false);
+		str_append_c (output, '/');
+		str_append (output, def);
+	}
+}
+
+static size_t io_error_domain_tag;
+#define IO_ERROR (error_resolve_domain (&io_error_domain_tag))
+
+enum
+{
+	IO_ERROR_FAILED
+};
+
+static bool
+ensure_directory_existence (const char *path, struct error **e)
+{
+	struct stat st;
+
+	if (stat (path, &st))
+	{
+		if (mkdir (path, S_IRWXU | S_IRWXG | S_IRWXO))
+		{
+			error_set (e, IO_ERROR, IO_ERROR_FAILED,
+				"cannot create directory `%s': %s",
+				path, strerror (errno));
+			return false;
+		}
+	}
+	else if (!S_ISDIR (st.st_mode))
+	{
+		error_set (e, IO_ERROR, IO_ERROR_FAILED,
+			"cannot create directory `%s': %s",
+			path, "file exists but is not a directory");
+		return false;
+	}
+	return true;
+}
+
+static bool
+mkdir_with_parents (char *path, struct error **e)
+{
+	char *p = path;
+
+	// XXX: This is prone to the TOCTTOU problem.  The solution would be to
+	//   rewrite the function using the {mkdir,fstat}at() functions from
+	//   POSIX.1-2008, ideally returning a file descriptor to the open
+	//   directory, with the current code as a fallback.  Or to use chdir().
+	while ((p = strchr (p + 1, '/')))
+	{
+		*p = '\0';
+		bool success = ensure_directory_existence (path, e);
+		*p = '/';
+
+		if (!success)
+			return false;
+	}
+
+	return ensure_directory_existence (path, e);
+}
+
+static bool
+set_boolean_if_valid (bool *out, const char *s)
+{
+	if      (!strcasecmp (s, "yes"))    *out = true;
+	else if (!strcasecmp (s, "no"))     *out = false;
+	else if (!strcasecmp (s, "on"))     *out = true;
+	else if (!strcasecmp (s, "off"))    *out = false;
+	else if (!strcasecmp (s, "true"))   *out = true;
+	else if (!strcasecmp (s, "false"))  *out = false;
+	else return false;
+
+	return true;
+}
+
+static void
+regerror_to_str (int code, const regex_t *preg, struct str *out)
+{
+	size_t required = regerror (code, preg, NULL, 0);
+	str_ensure_space (out, required);
+	out->len += regerror (code, preg,
+		out->str + out->len, out->alloc - out->len) - 1;
+}
+
+static size_t regex_error_domain_tag;
+#define REGEX_ERROR (error_resolve_domain (&regex_error_domain_tag))
+
+enum
+{
+	REGEX_ERROR_COMPILATION_FAILED
+};
+
+static bool
+regex_match (const char *regex, const char *s, struct error **e)
+{
+	regex_t re;
+	int err = regcomp (&re, regex, REG_EXTENDED | REG_NOSUB);
+	if (err)
+	{
+		struct str desc;
+
+		str_init (&desc);
+		regerror_to_str (err, &re, &desc);
+		error_set (e, REGEX_ERROR, REGEX_ERROR_COMPILATION_FAILED,
+			"failed to compile regular expression: %s", desc.str);
+		str_free (&desc);
+		return false;
+	}
+
+	bool result = regexec (&re, s, 0, NULL, 0) != REG_NOMATCH;
+	regfree (&re);
+	return result;
+}
+
+static bool
+read_line (FILE *fp, struct str *s)
+{
+	int c;
+	bool at_end = true;
+
+	str_reset (s);
+	while ((c = fgetc (fp)) != EOF)
+	{
+		at_end = false;
+		if (c == '\r')
+			continue;
+		if (c == '\n')
+			break;
+		str_append_c (s, c);
+	}
+
+	return !at_end;
+}
+
+#define XSSL_ERROR_TRY_AGAIN INT_MAX
+
+/// A small wrapper around SSL_get_error() to simplify further handling
+static int
+xssl_get_error (SSL *ssl, int result, const char **error_info)
+{
+	int error = SSL_get_error (ssl, result);
+	switch (error)
+	{
+	case SSL_ERROR_NONE:
+	case SSL_ERROR_ZERO_RETURN:
+	case SSL_ERROR_WANT_READ:
+	case SSL_ERROR_WANT_WRITE:
+		return error;
+	case SSL_ERROR_SYSCALL:
+		if ((error = ERR_get_error ()))
+			*error_info = ERR_error_string (error, NULL);
+		else if (result == 0)
+			// An EOF that's not according to the protocol is still an EOF
+			return SSL_ERROR_ZERO_RETURN;
+		else
+		{
+			if (errno == EINTR)
+				return XSSL_ERROR_TRY_AGAIN;
+			*error_info = strerror (errno);
+		}
+		return SSL_ERROR_SSL;
+	default:
+		if ((error = ERR_get_error ()))
+			*error_info = ERR_error_string (error, NULL);
+		else
+			*error_info = "Unknown error";
+		return SSL_ERROR_SSL;
+	}
+}
+
+// --- IRC utilities -----------------------------------------------------------
+
+struct irc_message
+{
+	char *prefix;
+	char *command;
+	struct str_vector params;
+};
+
+static void
+irc_parse_message (struct irc_message *msg, const char *line)
+{
+	msg->prefix = NULL;
+	msg->command = NULL;
+	str_vector_init (&msg->params);
+
+	// Prefix
+	if (*line == ':')
+	{
+		size_t prefix_len = strcspn (++line, " ");
+		msg->prefix = xstrndup (line, prefix_len);
+		line += prefix_len;
+	}
+
+	// Command name
+	{
+		while (*line == ' ')
+			line++;
+
+		size_t cmd_len = strcspn (line, " ");
+		msg->command = xstrndup (line, cmd_len);
+		line += cmd_len;
+	}
+
+	// Arguments
+	while (true)
+	{
+		while (*line == ' ')
+			line++;
+
+		if (*line == ':')
+		{
+			str_vector_add (&msg->params, ++line);
+			break;
+		}
+
+		size_t param_len = strcspn (line, " ");
+		if (!param_len)
+			break;
+
+		str_vector_add_owned (&msg->params, xstrndup (line, param_len));
+		line += param_len;
+	}
+}
+
+static void
+irc_free_message (struct irc_message *msg)
+{
+	free (msg->prefix);
+	free (msg->command);
+	str_vector_free (&msg->params);
+}
+
+static void
+irc_process_buffer (struct str *buf,
+	void (*callback)(const struct irc_message *, const char *, void *),
+	void *user_data)
+{
+	char *start = buf->str, *end = start + buf->len;
+	for (char *p = start; p + 1 < end; p++)
+	{
+		// Split the input on newlines
+		if (p[0] != '\r' || p[1] != '\n')
+			continue;
+
+		*p = 0;
+
+		struct irc_message msg;
+		irc_parse_message (&msg, start);
+		callback (&msg, start, user_data);
+		irc_free_message (&msg);
+
+		start = p + 2;
+	}
+
+	// XXX: we might want to just advance some kind of an offset to avoid
+	//   moving memory around unnecessarily.
+	str_remove_slice (buf, 0, start - buf->str);
+}
+
+static int
+irc_tolower (char c)
+{
+	if (c == '[')   return '{';
+	if (c == ']')   return '}';
+	if (c == '\\')  return '|';
+	if (c == '~')   return '^';
+	return c >= 'A' && c <= 'Z' ? c + ('a' - 'A') : c;
+}
+
+static int
+irc_strcmp (const char *a, const char *b)
+{
+	int x;
+	while (*a || *b)
+		if ((x = irc_tolower (*a++) - irc_tolower (*b++)))
+			return x;
+	return 0;
+}
+
+// --- Configuration -----------------------------------------------------------
+
+// The keys are stripped of surrounding whitespace, the values are not.
+
+static size_t config_error_domain_tag;
+#define CONFIG_ERROR (error_resolve_domain (&config_error_domain_tag))
+
+enum
+{
+	CONFIG_ERROR_MALFORMED
+};
+
+struct config_item
+{
+	const char *key;
+	const char *default_value;
+	const char *description;
+};
+
+static FILE *
+get_config_file (void)
+{
+	struct str_vector paths;
+	struct str config_home, file;
+	const char *xdg_config_dirs;
+	unsigned i;
+	FILE *fp = NULL;
+
+	str_vector_init (&paths);
+
+	str_init (&config_home);
+	get_xdg_home_dir (&config_home, "XDG_CONFIG_HOME", ".config");
+	str_vector_add (&paths, config_home.str);
+	str_free (&config_home);
+
+	if ((xdg_config_dirs = getenv ("XDG_CONFIG_DIRS")))
+		split_str_ignore_empty (xdg_config_dirs, ':', &paths);
+
+	str_init (&file);
+	for (i = 0; i < paths.len; i++)
+	{
+		// As per spec, relative paths are ignored
+		if (*paths.vector[i] != '/')
+			continue;
+
+		str_reset (&file);
+		str_append (&file, paths.vector[i]);
+		str_append (&file, "/" PROGRAM_NAME "/" PROGRAM_NAME ".conf");
+
+		if ((fp = fopen (file.str, "r")))
+			break;
+	}
+
+	str_free (&file);
+	str_vector_free (&paths);
+	return fp;
+}
+
+static void
+load_config_defaults (struct str_map *config, const struct config_item *table)
+{
+	for (; table->key != NULL; table++)
+		if (table->default_value)
+			str_map_set (config, table->key, xstrdup (table->default_value));
+		else
+			str_map_set (config, table->key, NULL);
+}
+
+static bool
+read_config_file (struct str_map *config, struct error **e)
+{
+	struct str line;
+	FILE *fp = get_config_file ();
+	unsigned line_no = 0;
+	bool errors = false;
+
+	if (!fp)
+		return true;
+
+	str_init (&line);
+	for (line_no = 1; read_line (fp, &line); line_no++)
+	{
+		char *start = line.str;
+		if (*start == '#')
+			continue;
+
+		while (isspace (*start))
+			start++;
+
+		char *end = strchr (start, '=');
+		if (!end)
+		{
+			if (*start)
+			{
+				error_set (e, CONFIG_ERROR, CONFIG_ERROR_MALFORMED,
+					"line %u in config: %s", line_no, "malformed input");
+				errors = true;
+				break;
+			}
+		}
+		else
+		{
+			char *value = end + 1;
+			do
+				*end = '\0';
+			while (isspace (*--end));
+
+			str_map_set (config, start, xstrdup (value));
+		}
+	}
+
+	str_free (&line);
+	fclose (fp);
+
+	return !errors;
+}
+
+static char *
+write_default_config (const char *filename, const struct config_item *table,
+	struct error **e)
+{
+	struct str path, base;
+
+	str_init (&path);
+	str_init (&base);
+
+	if (filename)
+	{
+		char *tmp = xstrdup (filename);
+		str_append (&path, dirname (tmp));
+		strcpy (tmp, filename);
+		str_append (&base, basename (tmp));
+		free (tmp);
+	}
+	else
+	{
+		get_xdg_home_dir (&path, "XDG_CONFIG_HOME", ".config");
+		str_append (&path, "/" PROGRAM_NAME);
+		str_append (&base, PROGRAM_NAME ".conf");
+	}
+
+	if (!mkdir_with_parents (path.str, e))
+		goto error;
+
+	str_append_c (&path, '/');
+	str_append_str (&path, &base);
+
+	FILE *fp = fopen (path.str, "w");
+	if (!fp)
+	{
+		error_set (e, IO_ERROR, IO_ERROR_FAILED,
+			"could not open `%s' for writing: %s", path.str, strerror (errno));
+		goto error;
+	}
+
+	errno = 0;
+	for (; table->key != NULL; table++)
+	{
+		fprintf (fp, "# %s\n", table->description);
+		if (table->default_value)
+			fprintf (fp, "%s=%s\n", table->key, table->default_value);
+		else
+			fprintf (fp, "#%s=\n", table->key);
+	}
+	fclose (fp);
+	if (errno)
+	{
+		error_set (e, IO_ERROR, IO_ERROR_FAILED,
+			"writing to `%s' failed: %s", path.str, strerror (errno));
+		goto error;
+	}
+
+	str_free (&base);
+	return str_steal (&path);
+
+error:
+	str_free (&base);
+	str_free (&path);
+	return NULL;
+
+}
diff --git a/src/kike.c b/src/kike.c
new file mode 100644
index 0000000..bf13476
--- /dev/null
+++ b/src/kike.c
@@ -0,0 +1,796 @@
+/*
+ * kike.c: the experimental IRC daemon
+ *
+ * Copyright (c) 2014, Přemysl Janouch <p.janouch@gmail.com>
+ * All rights reserved.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * 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.
+ *
+ */
+
+#define PROGRAM_NAME "kike"
+#define PROGRAM_VERSION "alpha"
+
+#include "common.c"
+
+// --- Configuration (application-specific) ------------------------------------
+
+static struct config_item g_config_table[] =
+{
+	{ "server_name",     NULL,              "Server name"                    },
+	{ "bind_host",       NULL,              "Address of the IRC server"      },
+	{ "bind_port",       "6667",            "Port of the IRC server"         },
+	{ "ssl_cert",        NULL,              "Server SSL certificate (PEM)"   },
+	{ "ssl_key",         NULL,              "Server SSL private key (PEM)"   },
+
+	{ "max_connections", NULL,              "Maximum client connections"     },
+	{ NULL,              NULL,              NULL                             }
+};
+
+// --- Signals -----------------------------------------------------------------
+
+static int g_signal_pipe[2];            ///< A pipe used to signal... signals
+
+/// Program termination has been requested by a signal
+static volatile sig_atomic_t g_termination_requested;
+
+static void
+sigterm_handler (int signum)
+{
+	(void) signum;
+
+	g_termination_requested = true;
+
+	int original_errno = errno;
+	if (write (g_signal_pipe[1], "t", 1) == -1)
+		soft_assert (errno == EAGAIN);
+	errno = original_errno;
+}
+
+static void
+setup_signal_handlers (void)
+{
+	if (pipe (g_signal_pipe) == -1)
+	{
+		print_fatal ("pipe: %s", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+
+	set_cloexec (g_signal_pipe[0]);
+	set_cloexec (g_signal_pipe[1]);
+
+	// So that the pipe cannot overflow; it would make write() block within
+	// the signal handler, which is something we really don't want to happen.
+	// The same holds true for read().
+	set_blocking (g_signal_pipe[0], false);
+	set_blocking (g_signal_pipe[1], false);
+
+	signal (SIGPIPE, SIG_IGN);
+
+	struct sigaction sa;
+	sa.sa_flags = SA_RESTART;
+	sigemptyset (&sa.sa_mask);
+	sa.sa_handler = sigterm_handler;
+	if (sigaction (SIGINT, &sa, NULL) == -1
+	 || sigaction (SIGTERM, &sa, NULL) == -1)
+	{
+		print_error ("sigaction: %s", strerror (errno));
+		exit (EXIT_FAILURE);
+	}
+}
+
+// --- Application data --------------------------------------------------------
+
+enum
+{
+	IRC_USER_MODE_INVISIBLE          = (1 << 0),
+	IRC_USER_MODE_RX_WALLOPS         = (1 << 1),
+	IRC_USER_MODE_RESTRICTED         = (1 << 2),
+	IRC_USER_MODE_OPERATOR           = (1 << 3),
+	IRC_USER_MODE_RX_SERVER_NOTICES  = (1 << 4)
+};
+
+struct connection
+{
+	struct connection *next;            ///< The next link in a chain
+	struct connection *prev;            ///< The previous link in a chain
+
+	struct server_context *ctx;         ///< Server context
+
+	int socket_fd;                      ///< The TCP socket
+	struct str read_buffer;             ///< Unprocessed input
+	struct str write_buffer;            ///< Output yet to be sent out
+
+	unsigned initialized    : 1;        ///< Has any data been received yet?
+	unsigned ssl_rx_want_tx : 1;        ///< SSL_read() wants to write
+	unsigned ssl_tx_want_rx : 1;        ///< SSL_write() wants to read
+
+	SSL_CTX *ssl_ctx;                   ///< SSL context
+	SSL *ssl;                           ///< SSL connection
+
+	char *nickname;                     ///< IRC nickname (main identifier)
+	char *username;                     ///< IRC username
+	char *fullname;                     ///< IRC fullname (e-mail)
+
+	char *hostname;                     ///< Hostname shown to the network
+
+	unsigned mode;                      ///< User's mode
+	char *away_message;                 ///< Away message
+};
+
+static void
+connection_init (struct connection *self)
+{
+	memset (self, 0, sizeof *self);
+
+	self->socket_fd = -1;
+	str_init (&self->read_buffer);
+	str_init (&self->write_buffer);
+}
+
+static void
+connection_free (struct connection *self)
+{
+	if (!soft_assert (self->socket_fd == -1))
+		xclose (self->socket_fd);
+	if (self->ssl_ctx)
+		SSL_CTX_free (self->ssl_ctx);
+	if (self->ssl)
+		SSL_free (self->ssl);
+
+	str_free (&self->read_buffer);
+	str_free (&self->write_buffer);
+
+	free (self->nickname);
+	free (self->username);
+	free (self->fullname);
+
+	free (self->hostname);
+	free (self->away_message);
+}
+
+enum
+{
+	IRC_CHAN_MODE_INVITE_ONLY      = (1 << 0),
+	IRC_CHAN_MODE_MODERATED        = (1 << 1),
+	IRC_CHAN_MODE_NO_OUTSIDE_MSGS  = (1 << 2),
+	IRC_CHAN_MODE_SECRET           = (1 << 3),
+	IRC_CHAN_MODE_PRIVATE          = (1 << 4),
+	IRC_CHAN_MODE_PROTECTED_TOPIC  = (1 << 5),
+	IRC_CHAN_MODE_QUIET            = (1 << 6)
+};
+
+struct channel
+{
+	struct server_context *ctx;         ///< Server context
+
+	char *name;                         ///< Channel name
+	unsigned modes;                     ///< Channel modes
+	char *key;                          ///< Channel key
+	long user_limit;                    ///< User limit or -1
+
+	struct str_vector ban_list;         ///< Ban list
+	struct str_vector exception_list;   ///< Exceptions from bans
+	struct str_vector invite_list;      ///< Exceptions from +I
+};
+
+static void
+channel_init (struct channel *self)
+{
+	memset (self, 0, sizeof *self);
+
+	str_vector_init (&self->ban_list);
+	str_vector_init (&self->exception_list);
+	str_vector_init (&self->invite_list);
+}
+
+static void
+channel_free (struct channel *self)
+{
+	free (self->name);
+	free (self->key);
+
+	str_vector_free (&self->ban_list);
+	str_vector_free (&self->exception_list);
+	str_vector_free (&self->invite_list);
+}
+
+struct server_context
+{
+	struct str_map config;              ///< Server configuration
+
+	int listen_fd;                      ///< Listening socket FD
+	struct connection *clients;         ///< Client connections
+
+	struct str_map users;               ///< Maps nicknames to connections
+	struct str_map channels;            ///< Maps channel names to data
+
+	struct poller poller;               ///< Manages polled description
+	bool polling;                       ///< The event loop is running
+};
+
+static void
+server_context_init (struct server_context *self)
+{
+	str_map_init (&self->config);
+	self->config.free = free;
+	load_config_defaults (&self->config, g_config_table);
+
+	self->listen_fd = -1;
+	self->clients = NULL;
+
+	str_map_init (&self->users);
+	// TODO: set channel_free() as the free function?
+	str_map_init (&self->channels);
+
+	poller_init (&self->poller);
+	self->polling = false;
+}
+
+static void
+server_context_free (struct server_context *self)
+{
+	str_map_free (&self->config);
+
+	if (self->listen_fd != -1)
+		xclose (self->listen_fd);
+
+	// TODO: terminate the connections properly before this is called
+	struct connection *link, *tmp;
+	for (link = self->clients; link; link = tmp)
+	{
+		tmp = link->next;
+		connection_free (link);
+		free (link);
+	}
+
+	str_map_free (&self->users);
+	str_map_free (&self->channels);
+	poller_free (&self->poller);
+}
+
+// --- Main program ------------------------------------------------------------
+
+static size_t network_error_domain_tag;
+#define NETWORK_ERROR (error_resolve_domain (&network_error_domain_tag))
+
+enum
+{
+	NETWORK_ERROR_INVALID_CONFIGURATION,
+	NETWORK_ERROR_FAILED
+};
+
+static bool
+irc_autodetect_ssl (struct connection *conn)
+{
+	// Trivial SSL/TLS autodetection.  The first block of data returned by
+	// recv() must be at least three bytes long for this to work reliably,
+	// but that should not pose a problem in practice.
+	//
+	// SSL2:      1xxx xxxx | xxxx xxxx |    <1>
+	//               (message length)  (client hello)
+	// SSL3/TLS:    <22>    |    <3>    | xxxx xxxx
+	//           (handshake)|  (protocol version)
+	//
+	// Such byte sequences should never occur at the beginning of regular IRC
+	// communication, which usually begins with USER/NICK/PASS/SERVICE.
+
+	char buf[3];
+start:
+	switch (recv (conn->socket_fd, buf, sizeof buf, MSG_PEEK))
+	{
+	case 3:
+		if ((buf[0] & 0x80) && buf[2] == 1)
+			return true;
+	case 2:
+		if (buf[0] == 22 && buf[1] == 3)
+			return true;
+		break;
+	case 1:
+		if (buf[0] == 22)
+			return true;
+		break;
+	case 0:
+		break;
+	default:
+		if (errno == EINTR)
+			goto start;
+	}
+	return false;
+}
+
+static int
+irc_ssl_verify_callback (int verify_ok, X509_STORE_CTX *ctx)
+{
+	(void) verify_ok;
+	(void) ctx;
+
+	// We only want to provide additional privileges based on the client's
+	// certificate, so let's not terminate the connection because of a failure.
+	return 1;
+}
+
+static bool
+irc_initialize_ssl (struct connection *conn)
+{
+	struct server_context *ctx = conn->ctx;
+
+	conn->ssl_ctx = SSL_CTX_new (SSLv23_server_method ());
+	if (!conn->ssl_ctx)
+		goto error_ssl_1;
+	SSL_CTX_set_verify (conn->ssl_ctx,
+		SSL_VERIFY_PEER | SSL_VERIFY_CLIENT_ONCE, irc_ssl_verify_callback);
+	// XXX: maybe we should call SSL_CTX_set_options() for some workarounds
+
+	conn->ssl = SSL_new (conn->ssl_ctx);
+	if (!conn->ssl)
+		goto error_ssl_2;
+
+	const char *ssl_cert = str_map_find (&ctx->config, "ssl_cert");
+	if (ssl_cert
+	 && !SSL_CTX_use_certificate_chain_file (conn->ssl_ctx, ssl_cert))
+	{
+		// XXX: perhaps we should read the file ourselves for better messages
+		print_error ("%s: %s", "setting the SSL client certificate failed",
+			ERR_error_string (ERR_get_error (), NULL));
+	}
+
+	const char *ssl_key = str_map_find (&ctx->config, "ssl_key");
+	if (ssl_key
+	 && !SSL_use_PrivateKey_file (conn->ssl, ssl_key, SSL_FILETYPE_PEM))
+	{
+		// XXX: perhaps we should read the file ourselves for better messages
+		print_error ("%s: %s", "setting the SSL private key failed",
+			ERR_error_string (ERR_get_error (), NULL));
+	}
+
+	// TODO: SSL_check_private_key(conn->ssl)?  It is has probably already been
+	//   checked by SSL_use_PrivateKey_file() above.
+
+	SSL_set_accept_state (conn->ssl);
+	if (!SSL_set_fd (conn->ssl, conn->socket_fd))
+		goto error_ssl_3;
+	// Gah, spare me your awkward semantics, I just want to push data!
+	// XXX: do we want SSL_MODE_AUTO_RETRY as well?  I guess not.
+	SSL_set_mode (conn->ssl,
+		SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER | SSL_MODE_ENABLE_PARTIAL_WRITE);
+	return true;
+
+error_ssl_3:
+	SSL_free (conn->ssl);
+	conn->ssl = NULL;
+error_ssl_2:
+	SSL_CTX_free (conn->ssl_ctx);
+	conn->ssl_ctx = NULL;
+error_ssl_1:
+	// XXX: these error strings are really nasty; also there could be
+	//   multiple errors on the OpenSSL stack.
+	print_error ("%s: %s", "could not initialize SSL",
+		ERR_error_string (ERR_get_error (), NULL));
+	return false;
+}
+
+static void
+connection_abort (struct connection *conn, const char *reason)
+{
+	// TODO: send a QUIT message with `reason' || "Client exited"
+	(void) reason;
+
+	// TODO: do further cleanup if the client has successfully registered
+
+	struct server_context *ctx = conn->ctx;
+	ssize_t i = poller_find_by_fd (&ctx->poller, conn->socket_fd);
+	if (i != -1)
+		poller_remove_at_index (&ctx->poller, i);
+
+	xclose (conn->socket_fd);
+	conn->socket_fd = -1;
+	connection_free (conn);
+	LIST_UNLINK (ctx->clients, conn);
+	free (conn);
+}
+
+static void
+irc_process_message (const struct irc_message *msg,
+	const char *raw, void *user_data)
+{
+	struct connection *conn = user_data;
+	// TODO
+}
+
+static bool
+irc_try_read (struct connection *conn)
+{
+	// TODO
+	return false;
+}
+
+static bool
+irc_try_read_ssl (struct connection *conn)
+{
+	if (conn->ssl_tx_want_rx)
+		return true;
+
+	struct str *buf = &conn->read_buffer;
+	conn->ssl_rx_want_tx = false;
+	while (true)
+	{
+		str_ensure_space (buf, 512);
+		int n_read = SSL_read (conn->ssl, buf->str + buf->len,
+			buf->alloc - buf->len - 1 /* null byte */);
+
+		const char *error_info = NULL;
+		switch (xssl_get_error (conn->ssl, n_read, &error_info))
+		{
+		case SSL_ERROR_NONE:
+			buf->str[buf->len += n_read] = '\0';
+			// TODO: discard characters above the 512 character limit
+			irc_process_buffer (buf, irc_process_message, conn);
+			continue;
+		case SSL_ERROR_ZERO_RETURN:
+			connection_abort (conn, NULL);
+			return false;
+		case SSL_ERROR_WANT_READ:
+			return true;
+		case SSL_ERROR_WANT_WRITE:
+			conn->ssl_rx_want_tx = true;
+			return false;
+		case XSSL_ERROR_TRY_AGAIN:
+			continue;
+		default:
+			print_debug ("%s: %s: %s", __func__, "SSL_read", error_info);
+			connection_abort (conn, error_info);
+			return false;
+		}
+	}
+}
+
+static bool
+irc_try_write (struct connection *conn)
+{
+	// TODO
+	return false;
+}
+
+static bool
+irc_try_write_ssl (struct connection *conn)
+{
+	if (conn->ssl_rx_want_tx)
+		return true;
+
+	struct str *buf = &conn->write_buffer;
+	conn->ssl_tx_want_rx = false;
+	while (buf->len)
+	{
+		int n_written = SSL_write (conn->ssl, buf->str, buf->len);
+
+		const char *error_info = NULL;
+		switch (xssl_get_error (conn->ssl, n_written, &error_info))
+		{
+		case SSL_ERROR_NONE:
+			str_remove_slice (buf, 0, n_written);
+			continue;
+		case SSL_ERROR_ZERO_RETURN:
+			connection_abort (conn, NULL);
+			return false;
+		case SSL_ERROR_WANT_WRITE:
+			return true;
+		case SSL_ERROR_WANT_READ:
+			conn->ssl_tx_want_rx = true;
+			return false;
+		case XSSL_ERROR_TRY_AGAIN:
+			continue;
+		default:
+			print_debug ("%s: %s: %s", __func__, "SSL_write", error_info);
+			connection_abort (conn, error_info);
+			return false;
+		}
+	}
+	return true;
+}
+
+static void
+on_irc_client_ready (const struct pollfd *pfd, void *user_data)
+{
+	// XXX: check/load `ssl_cert' and `ssl_key' earlier?
+	struct connection *conn = user_data;
+	if (!conn->initialized)
+	{
+		hard_assert (pfd->events == POLLIN);
+		// XXX: what with the error from irc_initialize_ssl()?
+		if (irc_autodetect_ssl (conn) && !irc_initialize_ssl (conn))
+		{
+			connection_abort (conn, NULL);
+			return;
+		}
+		conn->initialized = true;
+	}
+
+	// FIXME: aborting a connection inside try_read() will fuck things up
+	int new_events = 0;
+	if (conn->ssl)
+	{
+		// Reads may want to write, writes may want to read, poll() may
+		// return unexpected things in `revents'... let's try both
+		irc_try_read_ssl (conn) && irc_try_write_ssl (conn);
+
+		new_events |= POLLIN;
+		if (conn->write_buffer.len || conn->ssl_rx_want_tx)
+			new_events |= POLLOUT;
+
+		// While we're waiting for an opposite event, we ignore the original
+		if (conn->ssl_rx_want_tx)  new_events &= ~POLLIN;
+		if (conn->ssl_tx_want_rx)  new_events &= ~POLLOUT;
+	}
+	else
+	{
+		irc_try_read (conn) && irc_try_write (conn);
+
+		new_events |= POLLIN;
+		if (conn->write_buffer.len)
+			new_events |= POLLOUT;
+	}
+
+	hard_assert (new_events != 0);
+	if (pfd->events != new_events)
+		poller_set (&conn->ctx->poller, conn->socket_fd, new_events,
+			(poller_dispatcher_func) on_irc_client_ready, conn);
+}
+
+static void
+on_irc_connection_available (const struct pollfd *pfd, void *user_data)
+{
+	(void) pfd;
+	struct server_context *ctx = user_data;
+
+	// TODO: stop accepting new connections when `max_connections' is reached
+
+	while (true)
+	{
+		// XXX: `struct sockaddr_storage' is not the most portable thing
+		struct sockaddr_storage peer;
+		socklen_t peer_len = sizeof peer;
+
+		int fd = accept (ctx->listen_fd, (struct sockaddr *) &peer, &peer_len);
+		if (fd == -1)
+		{
+			if (errno == EAGAIN)
+				break;
+			if (errno == EINTR)
+				continue;
+			if (errno == ECONNABORTED)
+				continue;
+
+			// TODO: handle resource exhaustion (EMFILE, ENFILE) specially
+			//   (stop accepting new connections and wait until we close some).
+			print_fatal ("%s: %s", "accept", strerror (errno));
+
+			// FIXME: handle this better, bring the server down cleanly.
+			exit (EXIT_FAILURE);
+		}
+
+		char host[NI_MAXHOST] = "unknown", port[NI_MAXSERV] = "unknown";
+		int err = getnameinfo ((struct sockaddr *) &peer, peer_len,
+			host, sizeof host, port, sizeof port, AI_NUMERICSERV);
+		if (err)
+			print_debug ("%s: %s", "getnameinfo", gai_strerror (err));
+		print_debug ("accepted connection from %s:%s", host, port);
+
+		struct connection *conn = xmalloc (sizeof *conn);
+		connection_init (conn);
+		conn->socket_fd = fd;
+		conn->hostname = xstrdup (host);
+		LIST_PREPEND (ctx->clients, conn);
+
+		// TODO: set a timeout on the socket, something like 3 minutes, then we
+		//   should terminate the connection.
+		poller_set (&ctx->poller, conn->socket_fd, POLLIN,
+			(poller_dispatcher_func) on_irc_client_ready, conn);
+	}
+}
+
+static bool
+irc_listen (struct server_context *ctx, struct error **e)
+{
+	const char *bind_host = str_map_find (&ctx->config, "bind_host");
+	const char *bind_port = str_map_find (&ctx->config, "bind_port");
+	hard_assert (bind_port != NULL);  // We have a default value for this
+
+	struct addrinfo gai_hints, *gai_result, *gai_iter;
+	memset (&gai_hints, 0, sizeof gai_hints);
+
+	gai_hints.ai_socktype = SOCK_STREAM;
+	gai_hints.ai_flags = AI_PASSIVE;
+
+	int err = getaddrinfo (bind_host, bind_port, &gai_hints, &gai_result);
+	if (err)
+	{
+		error_set (e, NETWORK_ERROR, NETWORK_ERROR_FAILED, "%s: %s: %s",
+			"network setup failed", "getaddrinfo", gai_strerror (err));
+		return false;
+	}
+
+	int sockfd;
+	char real_host[NI_MAXHOST], real_port[NI_MAXSERV];
+
+	for (gai_iter = gai_result; gai_iter; gai_iter = gai_iter->ai_next)
+	{
+		sockfd = socket (gai_iter->ai_family,
+			gai_iter->ai_socktype, gai_iter->ai_protocol);
+		if (sockfd == -1)
+			continue;
+		set_cloexec (sockfd);
+
+		int yes = 1;
+		soft_assert (setsockopt (sockfd, SOL_SOCKET, SO_KEEPALIVE,
+			&yes, sizeof yes) != -1);
+		soft_assert (setsockopt (sockfd, SOL_SOCKET, SO_REUSEADDR,
+			&yes, sizeof yes) != -1);
+
+		real_host[0] = real_port[0] = '\0';
+		err = getnameinfo (gai_iter->ai_addr, gai_iter->ai_addrlen,
+			real_host, sizeof real_host, real_port, sizeof real_port,
+			NI_NUMERICHOST | NI_NUMERICSERV);
+		if (err)
+			print_debug ("%s: %s", "getnameinfo", gai_strerror (err));
+
+		if (bind (sockfd, gai_iter->ai_addr, gai_iter->ai_addrlen))
+			print_error ("bind() to %s:%s failed: %s",
+				real_host, real_port, strerror (errno));
+		else if (listen (sockfd, 16 /* arbitrary number */))
+			print_error ("listen() at %s:%s failed: %s",
+				real_host, real_port, strerror (errno));
+		else
+			break;
+
+		xclose (sockfd);
+	}
+
+	freeaddrinfo (gai_result);
+
+	if (!gai_iter)
+	{
+		error_set (e, NETWORK_ERROR, NETWORK_ERROR_FAILED,
+			"network setup failed");
+		return false;
+	}
+
+	ctx->listen_fd = sockfd;
+	poller_set (&ctx->poller, ctx->listen_fd, POLLIN,
+		(poller_dispatcher_func) on_irc_connection_available, ctx);
+
+	print_status ("listening at %s:%s", real_host, real_port);
+	return true;
+}
+
+static void
+on_signal_pipe_readable (const struct pollfd *fd, struct server_context *ctx)
+{
+	char *dummy;
+	(void) read (fd->fd, &dummy, 1);
+
+#if 0
+	// TODO
+	if (g_termination_requested && !ctx->quitting)
+	{
+		initiate_quit (ctx);
+	}
+#endif
+}
+
+static void
+print_usage (const char *program_name)
+{
+	fprintf (stderr,
+		"Usage: %s [OPTION]...\n"
+		"Experimental IRC server.\n"
+		"\n"
+		"  -d, --debug     run in debug mode (do not daemonize)\n"
+		"  -h, --help      display this help and exit\n"
+		"  -V, --version   output version information and exit\n"
+		"  --write-default-cfg [filename]\n"
+		"                  write a default configuration file and exit\n",
+		program_name);
+}
+
+int
+main (int argc, char *argv[])
+{
+	const char *invocation_name = argv[0];
+
+	struct error *e = NULL;
+	static struct option opts[] =
+	{
+		{ "debug",             no_argument,       NULL, 'd' },
+		{ "help",              no_argument,       NULL, 'h' },
+		{ "version",           no_argument,       NULL, 'V' },
+		{ "write-default-cfg", optional_argument, NULL, 'w' },
+		{ NULL,                0,                 NULL,  0  }
+	};
+
+	while (1)
+	{
+		int c, opt_index;
+
+		c = getopt_long (argc, argv, "dhV", opts, &opt_index);
+		if (c == -1)
+			break;
+
+		switch (c)
+		{
+		case 'd':
+			g_debug_mode = true;
+			break;
+		case 'h':
+			print_usage (invocation_name);
+			exit (EXIT_SUCCESS);
+		case 'V':
+			printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
+			exit (EXIT_SUCCESS);
+		case 'w':
+		{
+			char *filename = write_default_config (optarg, g_config_table, &e);
+			if (!filename)
+			{
+				print_fatal ("%s", e->message);
+				error_free (e);
+				exit (EXIT_FAILURE);
+			}
+			print_status ("configuration written to `%s'", filename);
+			free (filename);
+			exit (EXIT_SUCCESS);
+		}
+		default:
+			print_fatal ("error in options");
+			exit (EXIT_FAILURE);
+		}
+	}
+
+	print_status (PROGRAM_NAME " " PROGRAM_VERSION " starting");
+	setup_signal_handlers ();
+
+	SSL_library_init ();
+	atexit (EVP_cleanup);
+	SSL_load_error_strings ();
+	// XXX: ERR_load_BIO_strings()?  Anything else?
+	atexit (ERR_free_strings);
+
+	struct server_context ctx;
+	server_context_init (&ctx);
+
+	if (!read_config_file (&ctx.config, &e))
+	{
+		print_fatal ("error loading configuration: %s", e->message);
+		error_free (e);
+		exit (EXIT_FAILURE);
+	}
+
+	poller_set (&ctx.poller, g_signal_pipe[0], POLLIN,
+		(poller_dispatcher_func) on_signal_pipe_readable, &ctx);
+
+	if (!irc_listen (&ctx, &e))
+	{
+		print_error ("%s", e->message);
+		error_free (e);
+		exit (EXIT_FAILURE);
+	}
+
+	// TODO: daemonize
+
+	ctx.polling = true;
+	while (ctx.polling)
+		poller_run (&ctx.poller);
+
+	server_context_free (&ctx);
+	return EXIT_SUCCESS;
+}
diff --git a/src/zyklonb.c b/src/zyklonb.c
index a182d17..69c41c1 100644
--- a/src/zyklonb.c
+++ b/src/zyklonb.c
@@ -18,1464 +18,10 @@
  *
  */
 
-#define _POSIX_C_SOURCE 199309L
-#define _XOPEN_SOURCE 500
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <errno.h>
-#include <string.h>
-#include <stdarg.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <ctype.h>
-
-#include <unistd.h>
-#include <sys/wait.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <poll.h>
-#include <signal.h>
-#include <strings.h>
-#include <regex.h>
-#include <libgen.h>
-
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <netdb.h>
-
-#ifndef NI_MAXHOST
-#define NI_MAXHOST 1025
-#endif // ! NI_MAXHOST
-
-#include <getopt.h>
-#include <openssl/ssl.h>
-#include <openssl/err.h>
-#include "siphash.h"
-
 #define PROGRAM_NAME "ZyklonB"
 #define PROGRAM_VERSION "alpha"
 
-extern char **environ;
-
-#if defined __GNUC__
-#define ATTRIBUTE_PRINTF(x, y) __attribute__ ((format (printf, x, y)))
-#else // ! __GNUC__
-#define ATTRIBUTE_PRINTF(x, y)
-#endif // ! __GNUC__
-
-#if defined __GNUC__ && __GNUC__ >= 4
-#define ATTRIBUTE_SENTINEL __attribute__ ((sentinel))
-#else // ! __GNUC__ || __GNUC__ < 4
-#define ATTRIBUTE_SENTINEL
-#endif // ! __GNUC__ || __GNUC__ < 4
-
-#define N_ELEMENTS(a) (sizeof (a) / sizeof ((a)[0]))
-
-#define BLOCK_START  do {
-#define BLOCK_END    } while (0)
-
-// --- Utilities ---------------------------------------------------------------
-
-static void
-print_message (FILE *stream, const char *type, const char *fmt, ...)
-	ATTRIBUTE_PRINTF (3, 4);
-
-static void
-print_message (FILE *stream, const char *type, const char *fmt, ...)
-{
-	va_list ap;
-
-	va_start (ap, fmt);
-	fprintf (stream, "%s ", type);
-	vfprintf (stream, fmt, ap);
-	fputs ("\n", stream);
-	va_end (ap);
-}
-
-#define print_fatal(...)    print_message (stderr, "fatal:",   __VA_ARGS__)
-#define print_error(...)    print_message (stderr, "error:",   __VA_ARGS__)
-#define print_warning(...)  print_message (stderr, "warning:", __VA_ARGS__)
-#define print_status(...)   print_message (stdout, "--",       __VA_ARGS__)
-
-// --- Debugging and assertions ------------------------------------------------
-
-// We should check everything that may possibly fail with at least a soft
-// assertion, so that any causes for problems don't slip us by silently.
-//
-// `g_soft_asserts_are_deadly' may be useful while running inside a debugger.
-
-static bool g_debug_mode;               ///< Debug messages are printed
-static bool g_soft_asserts_are_deadly;  ///< soft_assert() aborts as well
-
-#define print_debug(...)                                                       \
-	BLOCK_START                                                                \
-		if (g_debug_mode)                                                      \
-			print_message (stderr, "debug:", __VA_ARGS__);                     \
-	BLOCK_END
-
-static void
-assertion_failure_handler (bool is_fatal, const char *file, int line,
-	const char *function, const char *condition)
-{
-	if (is_fatal)
-	{
-		print_fatal ("assertion failed [%s:%d in function %s]: %s",
-			file, line, function, condition);
-		abort ();
-	}
-	else
-		print_debug ("assertion failed [%s:%d in function %s]: %s",
-			file, line, function, condition);
-}
-
-#define soft_assert(condition)                                                 \
-	((condition) ? true :                                                      \
-		(assertion_failure_handler (g_soft_asserts_are_deadly,                 \
-		__FILE__, __LINE__, __func__, #condition), false))
-
-#define hard_assert(condition)                                                 \
-	((condition) ? (void) 0 :                                                  \
-		assertion_failure_handler (true,                                       \
-		__FILE__, __LINE__, __func__, #condition))
-
-// --- Safe memory management --------------------------------------------------
-
-// When a memory allocation fails and we need the memory, we're usually pretty
-// much fucked.  Use the non-prefixed versions when there's a legitimate
-// worry that an unrealistic amount of memory may be requested for allocation.
-
-// XXX: it's not a good idea to use print_message() as it may want to allocate
-//   further memory for printf() and the output streams.  That may fail.
-
-static void *
-xmalloc (size_t n)
-{
-	void *p = malloc (n);
-	if (!p)
-	{
-		print_fatal ("malloc: %s", strerror (errno));
-		exit (EXIT_FAILURE);
-	}
-	return p;
-}
-
-static void *
-xcalloc (size_t n, size_t m)
-{
-	void *p = calloc (n, m);
-	if (!p && n && m)
-	{
-		print_fatal ("calloc: %s", strerror (errno));
-		exit (EXIT_FAILURE);
-	}
-	return p;
-}
-
-static void *
-xrealloc (void *o, size_t n)
-{
-	void *p = realloc (o, n);
-	if (!p && n)
-	{
-		print_fatal ("realloc: %s", strerror (errno));
-		exit (EXIT_FAILURE);
-	}
-	return p;
-}
-
-static void *
-xreallocarray (void *o, size_t n, size_t m)
-{
-	if (m && n > SIZE_MAX / m)
-	{
-		errno = ENOMEM;
-		print_fatal ("reallocarray: %s", strerror (errno));
-		exit (EXIT_FAILURE);
-	}
-	return xrealloc (o, n * m);
-}
-
-static char *
-xstrdup (const char *s)
-{
-	return strcpy (xmalloc (strlen (s) + 1), s);
-}
-
-static char *
-xstrndup (const char *s, size_t n)
-{
-	size_t size = strlen (s);
-	if (n > size)
-		n = size;
-
-	char *copy = xmalloc (n + 1);
-	memcpy (copy, s, n);
-	copy[n] = '\0';
-	return copy;
-}
-
-// --- Double-linked list helpers ----------------------------------------------
-
-// The links of the list need to have the members `prev' and `next'.
-
-#define LIST_PREPEND(head, link)                                               \
-	BLOCK_START                                                                \
-		(link)->prev = NULL;                                                   \
-		(link)->next = (head);                                                 \
-		if ((link)->next)                                                      \
-			(link)->next->prev = (link);                                       \
-		(head) = (link);                                                       \
-	BLOCK_END
-
-#define LIST_UNLINK(head, link)                                                \
-	BLOCK_START                                                                \
-		if ((link)->prev)                                                      \
-			(link)->prev->next = (link)->next;                                 \
-		else                                                                   \
-			(head) = (link)->next;                                             \
-		if ((link)->next)                                                      \
-			(link)->next->prev = (link)->prev;                                 \
-	BLOCK_END
-
-// --- Dynamically allocated string array --------------------------------------
-
-struct str_vector
-{
-	char **vector;
-	size_t len;
-	size_t alloc;
-};
-
-static void
-str_vector_init (struct str_vector *self)
-{
-	self->alloc = 4;
-	self->len = 0;
-	self->vector = xcalloc (sizeof *self->vector, self->alloc);
-}
-
-static void
-str_vector_free (struct str_vector *self)
-{
-	unsigned i;
-	for (i = 0; i < self->len; i++)
-		free (self->vector[i]);
-
-	free (self->vector);
-	self->vector = NULL;
-}
-
-static void
-str_vector_add_owned (struct str_vector *self, char *s)
-{
-	self->vector[self->len] = s;
-	if (++self->len >= self->alloc)
-		self->vector = xreallocarray (self->vector,
-			sizeof *self->vector, (self->alloc <<= 1));
-	self->vector[self->len] = NULL;
-}
-
-static void
-str_vector_add (struct str_vector *self, const char *s)
-{
-	str_vector_add_owned (self, xstrdup (s));
-}
-
-static void
-str_vector_add_args (struct str_vector *self, const char *s, ...)
-	ATTRIBUTE_SENTINEL;
-
-static void
-str_vector_add_args (struct str_vector *self, const char *s, ...)
-{
-	va_list ap;
-
-	va_start (ap, s);
-	while (s)
-	{
-		str_vector_add (self, s);
-		s = va_arg (ap, const char *);
-	}
-	va_end (ap);
-}
-
-static void
-str_vector_add_vector (struct str_vector *self, char **vector)
-{
-	while (*vector)
-		str_vector_add (self, *vector++);
-}
-
-static void
-str_vector_remove (struct str_vector *self, size_t i)
-{
-	hard_assert (i < self->len);
-	free (self->vector[i]);
-	memmove (self->vector + i, self->vector + i + 1,
-		(self->len-- - i) * sizeof *self->vector);
-}
-
-// --- Dynamically allocated strings -------------------------------------------
-
-// Basically a string builder to abstract away manual memory management.
-
-struct str
-{
-	char *str;                          ///< String data, null terminated
-	size_t alloc;                       ///< How many bytes are allocated
-	size_t len;                         ///< How long the string actually is
-};
-
-/// We don't care about allocations that are way too large for the content, as
-/// long as the allocation is below the given threshold.  (Trivial heuristics.)
-#define STR_SHRINK_THRESHOLD (1 << 20)
-
-static void
-str_init (struct str *self)
-{
-	self->alloc = 16;
-	self->len = 0;
-	self->str = strcpy (xmalloc (self->alloc), "");
-}
-
-static void
-str_free (struct str *self)
-{
-	free (self->str);
-	self->str = NULL;
-	self->alloc = 0;
-	self->len = 0;
-}
-
-static void
-str_reset (struct str *self)
-{
-	str_free (self);
-	str_init (self);
-}
-
-static char *
-str_steal (struct str *self)
-{
-	char *str = self->str;
-	self->str = NULL;
-	str_free (self);
-	return str;
-}
-
-static void
-str_ensure_space (struct str *self, size_t n)
-{
-	// We allocate at least one more byte for the terminating null character
-	size_t new_alloc = self->alloc;
-	while (new_alloc <= self->len + n)
-		new_alloc <<= 1;
-	if (new_alloc != self->alloc)
-		self->str = xrealloc (self->str, (self->alloc = new_alloc));
-}
-
-static void
-str_append_data (struct str *self, const char *data, size_t n)
-{
-	str_ensure_space (self, n);
-	memcpy (self->str + self->len, data, n);
-	self->len += n;
-	self->str[self->len] = '\0';
-}
-
-static void
-str_append_c (struct str *self, char c)
-{
-	str_append_data (self, &c, 1);
-}
-
-static void
-str_append (struct str *self, const char *s)
-{
-	str_append_data (self, s, strlen (s));
-}
-
-static void
-str_append_str (struct str *self, const struct str *another)
-{
-	str_append_data (self, another->str, another->len);
-}
-
-static int
-str_append_vprintf (struct str *self, const char *fmt, va_list va)
-{
-	va_list ap;
-	int size;
-
-	va_copy (ap, va);
-	size = vsnprintf (NULL, 0, fmt, ap);
-	va_end (ap);
-
-	if (size < 0)
-		return -1;
-
-	va_copy (ap, va);
-	str_ensure_space (self, size);
-	size = vsnprintf (self->str + self->len, self->alloc - self->len, fmt, ap);
-	va_end (ap);
-
-	if (size > 0)
-		self->len += size;
-
-	return size;
-}
-
-static int
-str_append_printf (struct str *self, const char *fmt, ...)
-	ATTRIBUTE_PRINTF (2, 3);
-
-static int
-str_append_printf (struct str *self, const char *fmt, ...)
-{
-	va_list ap;
-
-	va_start (ap, fmt);
-	int size = str_append_vprintf (self, fmt, ap);
-	va_end (ap);
-	return size;
-}
-
-static void
-str_remove_slice (struct str *self, size_t start, size_t length)
-{
-	size_t end = start + length;
-	hard_assert (end <= self->len);
-	memmove (self->str + start, self->str + end, self->len - end);
-	self->str[self->len -= length] = '\0';
-
-	// Shrink the string if the allocation becomes way too large
-	if (self->alloc >= STR_SHRINK_THRESHOLD && self->len < (self->alloc >> 2))
-		self->str = xrealloc (self->str, self->alloc >>= 2);
-}
-
-// --- Errors ------------------------------------------------------------------
-
-// Error reporting utilities.  Inspired by GError, only much simpler.
-
-struct error
-{
-	size_t domain;                      ///< The domain of the error
-	int id;                             ///< The concrete error ID
-	char *message;                      ///< Textual description of the event
-};
-
-static size_t
-error_resolve_domain (size_t *tag)
-{
-	// This method is fairly sensitive to the order in which resolution
-	// requests come in, does not provide a good way of decoding the number
-	// back to a meaningful identifier, and may not play all too well with
-	// dynamic libraries when a module is e.g. statically linked into multiple
-	// libraries, but it's fast, simple, and more than enough for our purposes.
-	static size_t domain_counter;
-
-	if (!*tag)
-		*tag = ++domain_counter;
-	return *tag;
-}
-
-static void
-error_set (struct error **e, size_t domain, int id,
-	const char *message, ...) ATTRIBUTE_PRINTF (4, 5);
-
-static void
-error_set (struct error **e, size_t domain, int id,
-	const char *message, ...)
-{
-	if (!e)
-		return;
-
-	va_list ap;
-	va_start (ap, message);
-	int size = snprintf (NULL, 0, message, ap);
-	va_end (ap);
-
-	hard_assert (size >= 0);
-
-	struct error *tmp = xmalloc (sizeof *tmp);
-	tmp->domain = domain;
-	tmp->id = id;
-	tmp->message = xmalloc (size + 1);
-
-	va_start (ap, message);
-	size = snprintf (tmp->message, size + 1, message, ap);
-	va_end (ap);
-
-	hard_assert (size >= 0);
-
-	soft_assert (*e == NULL);
-	*e = tmp;
-}
-
-static void
-error_free (struct error *e)
-{
-	free (e->message);
-	free (e);
-}
-
-static void
-error_propagate (struct error **destination, struct error *source)
-{
-	if (!destination)
-	{
-		error_free (source);
-		return;
-	}
-
-	soft_assert (*destination == NULL);
-	*destination = source;
-}
-
-// --- String hash map ---------------------------------------------------------
-
-// The most basic <string, managed pointer> map (or associative array).
-
-struct str_map_link
-{
-	struct str_map_link *next;          ///< The next link in a chain
-	struct str_map_link *prev;          ///< The previous link in a chain
-
-	void *data;                         ///< Payload
-	size_t key_length;                  ///< Length of the key without '\0'
-	char key[];                         ///< The key for this link
-};
-
-struct str_map
-{
-	struct str_map_link **map;          ///< The hash table data itself
-	size_t alloc;                       ///< Number of allocated entries
-	size_t len;                         ///< Number of entries in the table
-	void (*free) (void *);              ///< Callback to destruct the payload
-};
-
-#define STR_MAP_MIN_ALLOC 16
-
-typedef void (*str_map_free_func) (void *);
-
-static void
-str_map_init (struct str_map *self)
-{
-	self->alloc = STR_MAP_MIN_ALLOC;
-	self->len = 0;
-	self->free = NULL;
-	self->map = xcalloc (self->alloc, sizeof *self->map);
-}
-
-static void
-str_map_free (struct str_map *self)
-{
-	struct str_map_link **iter, **end = self->map + self->alloc;
-	struct str_map_link *link, *tmp;
-
-	for (iter = self->map; iter < end; iter++)
-		for (link = *iter; link; link = tmp)
-		{
-			tmp = link->next;
-			if (self->free)
-				self->free (link->data);
-			free (link);
-		}
-
-	free (self->map);
-	self->map = NULL;
-}
-
-static uint64_t
-str_map_hash (const char *s, size_t len)
-{
-	static unsigned char key[16] = "SipHash 2-4 key!";
-	return siphash (key, (const void *) s, len);
-}
-
-static uint64_t
-str_map_pos (struct str_map *self, const char *s)
-{
-	size_t mask = self->alloc - 1;
-	return str_map_hash (s, strlen (s)) & mask;
-}
-
-static uint64_t
-str_map_link_hash (struct str_map_link *self)
-{
-	return str_map_hash (self->key, self->key_length);
-}
-
-static void
-str_map_resize (struct str_map *self, size_t new_size)
-{
-	struct str_map_link **old_map = self->map;
-	size_t i, old_size = self->alloc;
-
-	// Only powers of two, so that we don't need to compute the modulo
-	hard_assert ((new_size & (new_size - 1)) == 0);
-	size_t mask = new_size - 1;
-
-	self->alloc = new_size;
-	self->map = xcalloc (self->alloc, sizeof *self->map);
-	for (i = 0; i < old_size; i++)
-	{
-		struct str_map_link *iter = old_map[i], *next_iter;
-		while (iter)
-		{
-			next_iter = iter->next;
-			uint64_t pos = str_map_link_hash (iter) & mask;
-			LIST_PREPEND (self->map[pos], iter);
-			iter = next_iter;
-		}
-	}
-
-	free (old_map);
-}
-
-static void
-str_map_set (struct str_map *self, const char *key, void *value)
-{
-	uint64_t pos = str_map_pos (self, key);
-	struct str_map_link *iter = self->map[pos];
-	for (; iter; iter = iter->next)
-	{
-		if (strcmp (key, iter->key))
-			continue;
-
-		// Storing the same data doesn't destroy it
-		if (self->free && value != iter->data)
-			self->free (iter->data);
-
-		if (value)
-		{
-			iter->data = value;
-			return;
-		}
-
-		LIST_UNLINK (self->map[pos], iter);
-		free (iter);
-		self->len--;
-
-		// The array should be at least 1/4 full
-		if (self->alloc >= (STR_MAP_MIN_ALLOC << 2)
-		 && self->len < (self->alloc >> 2))
-			str_map_resize (self, self->alloc >> 2);
-		return;
-	}
-
-	if (!value)
-		return;
-
-	if (self->len >= self->alloc)
-	{
-		str_map_resize (self, self->alloc << 1);
-		pos = str_map_pos (self, key);
-	}
-
-	// Link in a new element for the given <key, value> pair
-	size_t key_length = strlen (key);
-	struct str_map_link *link = xmalloc (sizeof *link + key_length + 1);
-	link->data = value;
-	link->key_length = key_length;
-	memcpy (link->key, key, key_length + 1);
-
-	LIST_PREPEND (self->map[pos], link);
-	self->len++;
-}
-
-static void *
-str_map_find (struct str_map *self, const char *key)
-{
-	struct str_map_link *iter = self->map[str_map_pos (self, key)];
-	for (; iter; iter = iter->next)
-		if (!strcmp (key, (char *) iter + sizeof *iter))
-			return iter->data;
-	return NULL;
-}
-
-// --- File descriptor utilities -----------------------------------------------
-
-static void
-set_cloexec (int fd)
-{
-	soft_assert (fcntl (fd, F_SETFD, fcntl (fd, F_GETFD) | FD_CLOEXEC) != -1);
-}
-
-static bool
-set_blocking (int fd, bool blocking)
-{
-	int flags = fcntl (fd, F_GETFL);
-	hard_assert (flags != -1);
-
-	bool prev = !(flags & O_NONBLOCK);
-	if (blocking)
-		flags &= ~O_NONBLOCK;
-	else
-		flags |=  O_NONBLOCK;
-
-	hard_assert (fcntl (fd, F_SETFL, flags) != -1);
-	return prev;
-}
-
-static void
-xclose (int fd)
-{
-	while (close (fd) == -1)
-		if (!soft_assert (errno == EINTR))
-			break;
-}
-
-// --- Polling -----------------------------------------------------------------
-
-// Basically the poor man's GMainLoop/libev/libuv.  It might make some sense
-// to instead use those tested and proven libraries but we don't need much
-// and it's interesting to implement.
-
-// At the moment the FD's are stored in an unsorted array.  This is not ideal
-// complexity-wise but I don't think I have much of a choice with poll(),
-// and neither with epoll for that matter.
-//
-//                         unsorted array       sorted array
-//           search             O(n)       O(log n) [O(log log n)]
-//           insert by fd       O(n)                O(n)
-//           delete by fd       O(n)                O(n)
-//
-// Insertion in the unsorted array can be reduced to O(1) if I maintain a
-// bitmap of present FD's but that's still not a huge win.
-//
-// I don't expect this to be much of an issue, as there are typically not going
-// to be that many FD's to watch, and the linear approach is cache-friendly.
-
-typedef void (*poller_dispatcher_func) (const struct pollfd *, void *);
-
-#define POLLER_MIN_ALLOC 16
-
-#ifdef __linux__
-
-// I don't really need this, I've basically implemented this just because I can.
-
-#include <sys/epoll.h>
-
-struct poller_info
-{
-	int fd;                             ///< Our file descriptor
-	uint32_t events;                    ///< The events we registered
-	poller_dispatcher_func dispatcher;  ///< Event dispatcher
-	void *user_data;                    ///< User data
-};
-
-struct poller
-{
-	int epoll_fd;                       ///< The epoll FD
-	struct poller_info **info;          ///< Information associated with each FD
-	struct epoll_event *revents;        ///< Output array for epoll_wait()
-	size_t len;                         ///< Number of polled descriptors
-	size_t alloc;                       ///< Number of entries allocated
-
-	/// Index of the element in `revents' that's currently being dispatched,
-	/// or -1 if we're not dispatching at the moment.
-	int dispatch_iterator;
-
-	/// The total number of entries stored in `revents' by epoll_wait().
-	int dispatch_total;
-};
-
-static void
-poller_init (struct poller *self)
-{
-	self->epoll_fd = epoll_create (POLLER_MIN_ALLOC);
-	hard_assert (self->epoll_fd != -1);
-	set_cloexec (self->epoll_fd);
-
-	self->len = 0;
-	self->alloc = POLLER_MIN_ALLOC;
-	self->info = xcalloc (self->alloc, sizeof *self->info);
-	self->revents = xcalloc (self->alloc, sizeof *self->revents);
-
-	self->dispatch_iterator = -1;
-	self->dispatch_total = 0;
-}
-
-static void
-poller_free (struct poller *self)
-{
-	for (size_t i = 0; i < self->len; i++)
-	{
-		struct poller_info *info = self->info[i];
-		hard_assert (epoll_ctl (self->epoll_fd,
-			EPOLL_CTL_DEL, info->fd, (void *) "") != -1);
-		free (info);
-	}
-
-	xclose (self->epoll_fd);
-	free (self->info);
-	free (self->revents);
-}
-
-static ssize_t
-poller_find_by_fd (struct poller *self, int fd)
-{
-	for (size_t i = 0; i < self->len; i++)
-		if (self->info[i]->fd == fd)
-			return i;
-	return -1;
-}
-
-static void
-poller_ensure_space (struct poller *self)
-{
-	if (self->len < self->alloc)
-		return;
-
-	self->alloc <<= 1;
-	self->revents = xreallocarray
-		(self->revents, sizeof *self->revents, self->alloc);
-	self->info = xreallocarray
-		(self->info, sizeof *self->info, self->alloc);
-}
-
-static int
-poller_epoll_to_poll_events (int events)
-{
-	int result = 0;
-	if (events & EPOLLIN)   result |= POLLIN;
-	if (events & EPOLLOUT)  result |= POLLOUT;
-	if (events & EPOLLERR)  result |= POLLERR;
-	if (events & EPOLLHUP)  result |= POLLHUP;
-	if (events & EPOLLPRI)  result |= POLLPRI;
-	return result;
-}
-
-static uint32_t
-poller_poll_to_epoll_events (uint32_t events)
-{
-	uint32_t result = 0;
-	if (events & POLLIN)   result |= EPOLLIN;
-	if (events & POLLOUT)  result |= EPOLLOUT;
-	if (events & POLLERR)  result |= EPOLLERR;
-	if (events & POLLHUP)  result |= EPOLLHUP;
-	if (events & POLLPRI)  result |= EPOLLPRI;
-	return result;
-}
-
-static void
-poller_set (struct poller *self, int fd, short int events,
-	poller_dispatcher_func dispatcher, void *data)
-{
-	ssize_t index = poller_find_by_fd (self, fd);
-	bool modifying = true;
-	if (index == -1)
-	{
-		poller_ensure_space (self);
-		self->info[index = self->len++] = xcalloc (1, sizeof **self->info);
-		modifying = false;
-	}
-
-	struct poller_info *info = self->info[index];
-	info->fd = fd;
-	info->dispatcher = dispatcher;
-	info->user_data = data;
-
-	struct epoll_event event;
-	event.events = poller_poll_to_epoll_events (events);
-	event.data.ptr = info;
-	hard_assert (epoll_ctl (self->epoll_fd,
-		modifying ? EPOLL_CTL_MOD : EPOLL_CTL_ADD, fd, &event) != -1);
-}
-
-static void
-poller_remove_from_dispatch (struct poller *self,
-	const struct poller_info *info)
-{
-	if (self->dispatch_iterator == -1)
-		return;
-
-	int i;
-	for (i = self->dispatch_iterator; i < self->dispatch_total; i++)
-		if (self->revents[i].data.ptr == info)
-			break;
-	if (i == self->dispatch_total)
-		return;
-
-	if (i != --self->dispatch_total)
-		self->revents[i] = self->revents[self->dispatch_total];
-
-	// We've removed the element we're currently processing; go back one entry
-	// so that we don't skip the one we might have replaced it with.
-	if (i == self->dispatch_iterator)
-		self->dispatch_iterator--;
-}
-
-static void
-poller_remove_at_index (struct poller *self, size_t index)
-{
-	hard_assert (index < self->len);
-	struct poller_info *info = self->info[index];
-
-	poller_remove_from_dispatch (self, info);
-	hard_assert (epoll_ctl (self->epoll_fd,
-		EPOLL_CTL_DEL, info->fd, (void *) "") != -1);
-
-	free (info);
-	if (index != --self->len)
-		self->info[index] = self->info[self->len];
-}
-
-static void
-poller_run (struct poller *self)
-{
-	// Not reentrant
-	hard_assert (self->dispatch_iterator == -1);
-
-	int n_fds;
-	do
-		n_fds = epoll_wait (self->epoll_fd, self->revents, self->len, -1);
-	while (n_fds == -1 && errno == EINTR);
-
-	if (n_fds == -1)
-	{
-		print_fatal ("%s: %s", "epoll", strerror (errno));
-		exit (EXIT_FAILURE);
-	}
-
-	for (int i = 0; i < n_fds; i++)
-	{
-		struct epoll_event *revents = self->revents + i;
-		struct poller_info *info = revents->data.ptr;
-
-		struct pollfd pfd;
-		pfd.fd = info->fd;
-		pfd.revents = poller_epoll_to_poll_events (revents->events);
-		pfd.events = poller_epoll_to_poll_events (info->events);
-
-		self->dispatch_iterator = i;
-		self->dispatch_total = n_fds;
-
-		info->dispatcher (&pfd, info->user_data);
-
-		i = self->dispatch_iterator;
-		n_fds = self->dispatch_total;
-	}
-
-	self->dispatch_iterator = -1;
-	self->dispatch_total = 0;
-}
-
-#else  // !__linux__
-
-struct poller_info
-{
-	poller_dispatcher_func dispatcher;  ///< Event dispatcher
-	void *user_data;                    ///< User data
-};
-
-struct poller
-{
-	struct pollfd *fds;                 ///< Polled descriptors
-	struct poller_info *fds_info;       ///< Additional information for each FD
-	size_t len;                         ///< Number of polled descriptors
-	size_t alloc;                       ///< Number of entries allocated
-
-	int dispatch_index;                 ///< The currently dispatched FD or -1
-};
-
-static void
-poller_init (struct poller *self)
-{
-	self->alloc = POLLER_MIN_ALLOC;
-	self->len = 0;
-	self->fds = xcalloc (self->alloc, sizeof *self->fds);
-	self->fds_info = xcalloc (self->alloc, sizeof *self->fds_info);
-	self->dispatch_index = -1;
-}
-
-static void
-poller_free (struct poller *self)
-{
-	free (self->fds);
-	free (self->fds_info);
-}
-
-static ssize_t
-poller_find_by_fd (struct poller *self, int fd)
-{
-	for (size_t i = 0; i < self->len; i++)
-		if (self->fds[i].fd == fd)
-			return i;
-	return -1;
-}
-
-static void
-poller_ensure_space (struct poller *self)
-{
-	if (self->len < self->alloc)
-		return;
-
-	self->alloc <<= 1;
-	self->fds = xreallocarray (self->fds, sizeof *self->fds, self->alloc);
-	self->fds_info = xreallocarray
-		(self->fds_info, sizeof *self->fds_info, self->alloc);
-}
-
-static void
-poller_set (struct poller *self, int fd, short int events,
-	poller_dispatcher_func dispatcher, void *data)
-{
-	ssize_t index = poller_find_by_fd (self, fd);
-	if (index == -1)
-	{
-		poller_ensure_space (self);
-		index = self->len++;
-	}
-
-	struct pollfd *new_entry = self->fds + index;
-	memset (new_entry, 0, sizeof *new_entry);
-	new_entry->fd = fd;
-	new_entry->events = events;
-
-	self->fds_info[self->len] = (struct poller_info) { dispatcher, data };
-}
-
-static void
-poller_remove_at_index (struct poller *self, size_t index)
-{
-	hard_assert (index < self->len);
-	if (index == --self->len)
-		return;
-
-	// Make sure that we don't disrupt the dispatch loop; kind of crude
-	if ((int) index < self->dispatch_index)
-	{
-		memmove (self->fds + index, self->fds + index + 1,
-			(self->len - index) * sizeof *self->fds);
-		memmove (self->fds_info + index, self->fds_info + index + 1,
-			(self->len - index) * sizeof *self->fds_info);
-	}
-	else
-	{
-		self->fds[index]      = self->fds[self->len];
-		self->fds_info[index] = self->fds_info[self->len];
-	}
-
-	if ((int) index <= self->dispatch_index)
-		self->dispatch_index--;
-}
-
-static void
-poller_run (struct poller *self)
-{
-	// Not reentrant
-	hard_assert (self->dispatch_index == -1);
-
-	int result;
-	do
-		result = poll (self->fds, self->len, -1);
-	while (result == -1 && errno == EINTR);
-
-	if (result == -1)
-	{
-		print_fatal ("%s: %s", "poll", strerror (errno));
-		exit (EXIT_FAILURE);
-	}
-
-	for (int i = 0; i < (int) self->len; i++)
-	{
-		struct pollfd pfd = self->fds[i];
-		if (!pfd.revents)
-			continue;
-
-		struct poller_info *info = self->fds_info + i;
-		self->dispatch_index = i;
-		info->dispatcher (&pfd, info->user_data);
-		i = self->dispatch_index;
-	}
-
-	self->dispatch_index = -1;
-}
-
-#endif  // !__linux__
-
-// --- Utilities ---------------------------------------------------------------
-
-static void
-split_str_ignore_empty (const char *s, char delimiter, struct str_vector *out)
-{
-	const char *begin = s, *end;
-
-	while ((end = strchr (begin, delimiter)))
-	{
-		if (begin != end)
-			str_vector_add_owned (out, xstrndup (begin, end - begin));
-		begin = ++end;
-	}
-
-	if (*begin)
-		str_vector_add (out, begin);
-}
-
-static char *
-strip_str_in_place (char *s, const char *stripped_chars)
-{
-	char *end = s + strlen (s);
-	while (end > s && strchr (stripped_chars, end[-1]))
-		*--end = '\0';
-
-	char *start = s + strspn (s, stripped_chars);
-	if (start > s)
-		memmove (s, start, end - start + 1);
-	return s;
-}
-
-static bool
-str_append_env_path (struct str *output, const char *var, bool only_absolute)
-{
-	const char *value = getenv (var);
-
-	if (!value || (only_absolute && *value != '/'))
-		return false;
-
-	str_append (output, value);
-	return true;
-}
-
-static void
-get_xdg_home_dir (struct str *output, const char *var, const char *def)
-{
-	str_reset (output);
-	if (!str_append_env_path (output, var, true))
-	{
-		str_append_env_path (output, "HOME", false);
-		str_append_c (output, '/');
-		str_append (output, def);
-	}
-}
-
-static size_t io_error_domain_tag;
-#define IO_ERROR (error_resolve_domain (&io_error_domain_tag))
-
-enum
-{
-	IO_ERROR_FAILED
-};
-
-static bool
-ensure_directory_existence (const char *path, struct error **e)
-{
-	struct stat st;
-
-	if (stat (path, &st))
-	{
-		if (mkdir (path, S_IRWXU | S_IRWXG | S_IRWXO))
-		{
-			error_set (e, IO_ERROR, IO_ERROR_FAILED,
-				"cannot create directory `%s': %s",
-				path, strerror (errno));
-			return false;
-		}
-	}
-	else if (!S_ISDIR (st.st_mode))
-	{
-		error_set (e, IO_ERROR, IO_ERROR_FAILED,
-			"cannot create directory `%s': %s",
-			path, "file exists but is not a directory");
-		return false;
-	}
-	return true;
-}
-
-static bool
-mkdir_with_parents (char *path, struct error **e)
-{
-	char *p = path;
-
-	// XXX: This is prone to the TOCTTOU problem.  The solution would be to
-	//   rewrite the function using the {mkdir,fstat}at() functions from
-	//   POSIX.1-2008, ideally returning a file descriptor to the open
-	//   directory, with the current code as a fallback.  Or to use chdir().
-	while ((p = strchr (p + 1, '/')))
-	{
-		*p = '\0';
-		bool success = ensure_directory_existence (path, e);
-		*p = '/';
-
-		if (!success)
-			return false;
-	}
-
-	return ensure_directory_existence (path, e);
-}
-
-static bool
-set_boolean_if_valid (bool *out, const char *s)
-{
-	if      (!strcasecmp (s, "yes"))    *out = true;
-	else if (!strcasecmp (s, "no"))     *out = false;
-	else if (!strcasecmp (s, "on"))     *out = true;
-	else if (!strcasecmp (s, "off"))    *out = false;
-	else if (!strcasecmp (s, "true"))   *out = true;
-	else if (!strcasecmp (s, "false"))  *out = false;
-	else return false;
-
-	return true;
-}
-
-static void
-regerror_to_str (int code, const regex_t *preg, struct str *out)
-{
-	size_t required = regerror (code, preg, NULL, 0);
-	str_ensure_space (out, required);
-	out->len += regerror (code, preg,
-		out->str + out->len, out->alloc - out->len) - 1;
-}
-
-static size_t regex_error_domain_tag;
-#define REGEX_ERROR (error_resolve_domain (&regex_error_domain_tag))
-
-enum
-{
-	REGEX_ERROR_COMPILATION_FAILED
-};
-
-static bool
-regex_match (const char *regex, const char *s, struct error **e)
-{
-	regex_t re;
-	int err = regcomp (&re, regex, REG_EXTENDED | REG_NOSUB);
-	if (err)
-	{
-		struct str desc;
-
-		str_init (&desc);
-		regerror_to_str (err, &re, &desc);
-		error_set (e, REGEX_ERROR, REGEX_ERROR_COMPILATION_FAILED,
-			"failed to compile regular expression: %s", desc.str);
-		str_free (&desc);
-		return false;
-	}
-
-	bool result = regexec (&re, s, 0, NULL, 0) != REG_NOMATCH;
-	regfree (&re);
-	return result;
-}
-
-static bool
-read_line (FILE *fp, struct str *s)
-{
-	int c;
-	bool at_end = true;
-
-	str_reset (s);
-	while ((c = fgetc (fp)) != EOF)
-	{
-		at_end = false;
-		if (c == '\r')
-			continue;
-		if (c == '\n')
-			break;
-		str_append_c (s, c);
-	}
-
-	return !at_end;
-}
-
-// --- IRC utilities -----------------------------------------------------------
-
-struct irc_message
-{
-	char *prefix;
-	char *command;
-	struct str_vector params;
-};
-
-static void
-irc_parse_message (struct irc_message *msg, const char *line)
-{
-	msg->prefix = NULL;
-	msg->command = NULL;
-	str_vector_init (&msg->params);
-
-	// Prefix
-	if (*line == ':')
-	{
-		size_t prefix_len = strcspn (++line, " ");
-		msg->prefix = xstrndup (line, prefix_len);
-		line += prefix_len;
-	}
-
-	// Command name
-	{
-		while (*line == ' ')
-			line++;
-
-		size_t cmd_len = strcspn (line, " ");
-		msg->command = xstrndup (line, cmd_len);
-		line += cmd_len;
-	}
-
-	// Arguments
-	while (true)
-	{
-		while (*line == ' ')
-			line++;
-
-		if (*line == ':')
-		{
-			str_vector_add (&msg->params, ++line);
-			break;
-		}
-
-		size_t param_len = strcspn (line, " ");
-		if (!param_len)
-			break;
-
-		str_vector_add_owned (&msg->params, xstrndup (line, param_len));
-		line += param_len;
-	}
-}
-
-static void
-irc_free_message (struct irc_message *msg)
-{
-	free (msg->prefix);
-	free (msg->command);
-	str_vector_free (&msg->params);
-}
-
-static void
-irc_process_buffer (struct str *buf,
-	void (*callback)(const struct irc_message *, const char *, void *),
-	void *user_data)
-{
-	char *start = buf->str;
-	char *end = start + buf->len;
-
-	for (char *p = start; p + 1 < end; p++)
-	{
-		// Split the input on newlines
-		if (p[0] != '\r' || p[1] != '\n')
-			continue;
-
-		*p = 0;
-
-		struct irc_message msg;
-		irc_parse_message (&msg, start);
-		callback (&msg, start, user_data);
-		irc_free_message (&msg);
-
-		start = p + 2;
-	}
-
-	str_remove_slice (buf, 0, start - buf->str);
-}
-
-// --- Configuration -----------------------------------------------------------
-
-// The keys are stripped of surrounding whitespace, the values are not.
-
-static size_t config_error_domain_tag;
-#define CONFIG_ERROR (error_resolve_domain (&config_error_domain_tag))
-
-enum
-{
-	CONFIG_ERROR_MALFORMED
-};
-
-struct config_item
-{
-	const char *key;
-	const char *default_value;
-	const char *description;
-};
-
-static FILE *
-get_config_file (void)
-{
-	struct str_vector paths;
-	struct str config_home, file;
-	const char *xdg_config_dirs;
-	unsigned i;
-	FILE *fp = NULL;
-
-	str_vector_init (&paths);
-
-	str_init (&config_home);
-	get_xdg_home_dir (&config_home, "XDG_CONFIG_HOME", ".config");
-	str_vector_add (&paths, config_home.str);
-	str_free (&config_home);
-
-	if ((xdg_config_dirs = getenv ("XDG_CONFIG_DIRS")))
-		split_str_ignore_empty (xdg_config_dirs, ':', &paths);
-
-	str_init (&file);
-	for (i = 0; i < paths.len; i++)
-	{
-		// As per spec, relative paths are ignored
-		if (*paths.vector[i] != '/')
-			continue;
-
-		str_reset (&file);
-		str_append (&file, paths.vector[i]);
-		str_append (&file, "/" PROGRAM_NAME "/" PROGRAM_NAME ".conf");
-
-		if ((fp = fopen (file.str, "r")))
-			break;
-	}
-
-	str_free (&file);
-	str_vector_free (&paths);
-	return fp;
-}
-
-static bool
-read_config_file (struct str_map *config, struct error **e)
-{
-	struct str line;
-	FILE *fp = get_config_file ();
-	unsigned line_no = 0;
-	bool errors = false;
-
-	if (!fp)
-		return true;
-
-	str_init (&line);
-	for (line_no = 1; read_line (fp, &line); line_no++)
-	{
-		char *start = line.str;
-		if (*start == '#')
-			continue;
-
-		while (isspace (*start))
-			start++;
-
-		char *end = strchr (start, '=');
-		if (!end)
-		{
-			if (*start)
-			{
-				error_set (e, CONFIG_ERROR, CONFIG_ERROR_MALFORMED,
-					"line %u in config: %s", line_no, "malformed input");
-				errors = true;
-				break;
-			}
-		}
-		else
-		{
-			char *value = end + 1;
-			do
-				*end = '\0';
-			while (isspace (*--end));
-
-			str_map_set (config, start, xstrdup (value));
-		}
-	}
-
-	str_free (&line);
-	fclose (fp);
-
-	return !errors;
-}
+#include "common.c"
 
 // --- Configuration (application-specific) ------------------------------------
 
@@ -1498,18 +44,9 @@ static struct config_item g_config_table[] =
 	{ "plugins",         NULL,              "The plugins to load on startup" },
 	{ "plugin_dir",      NULL,              "Where to search for plugins"    },
 	{ "recover",         "on",              "Whether to re-launch on crash"  },
-};
 
-static void
-load_config_defaults (struct str_map *config)
-{
-	for (size_t i = 0; i < N_ELEMENTS (g_config_table); i++)
-	{
-		const struct config_item *item = g_config_table + i;
-		if (item->default_value)
-			str_map_set (config, item->key, xstrdup (item->default_value));
-	}
-}
+	{ NULL,              NULL,              NULL                             }
+};
 
 // --- Application data --------------------------------------------------------
 
@@ -1598,51 +135,51 @@ struct bot_context
 };
 
 static void
-bot_context_init (struct bot_context *ctx)
+bot_context_init (struct bot_context *self)
 {
-	str_map_init (&ctx->config);
-	ctx->config.free = free;
-	load_config_defaults (&ctx->config);
+	str_map_init (&self->config);
+	self->config.free = free;
+	load_config_defaults (&self->config, g_config_table);
 
-	ctx->irc_fd = -1;
-	str_init (&ctx->read_buffer);
-	ctx->irc_ready = false;
+	self->irc_fd = -1;
+	str_init (&self->read_buffer);
+	self->irc_ready = false;
 
-	ctx->ssl = NULL;
-	ctx->ssl_ctx = NULL;
+	self->ssl = NULL;
+	self->ssl_ctx = NULL;
 
-	ctx->plugins = NULL;
-	str_map_init (&ctx->plugins_by_name);
+	self->plugins = NULL;
+	str_map_init (&self->plugins_by_name);
 
-	poller_init (&ctx->poller);
-	ctx->quitting = false;
-	ctx->polling = false;
+	poller_init (&self->poller);
+	self->quitting = false;
+	self->polling = false;
 }
 
 static void
-bot_context_free (struct bot_context *ctx)
+bot_context_free (struct bot_context *self)
 {
-	str_map_free (&ctx->config);
-	str_free (&ctx->read_buffer);
+	str_map_free (&self->config);
+	str_free (&self->read_buffer);
 
 	// TODO: terminate the plugins properly before this is called
 	struct plugin_data *link, *tmp;
-	for (link = ctx->plugins; link; link = tmp)
+	for (link = self->plugins; link; link = tmp)
 	{
 		tmp = link->next;
 		plugin_data_free (link);
 		free (link);
 	}
 
-	if (ctx->irc_fd != -1)
-		xclose (ctx->irc_fd);
-	if (ctx->ssl)
-		SSL_free (ctx->ssl);
-	if (ctx->ssl_ctx)
-		SSL_CTX_free (ctx->ssl_ctx);
+	if (self->irc_fd != -1)
+		xclose (self->irc_fd);
+	if (self->ssl)
+		SSL_free (self->ssl);
+	if (self->ssl_ctx)
+		SSL_CTX_free (self->ssl_ctx);
 
-	str_map_free (&ctx->plugins_by_name);
-	poller_free (&ctx->poller);
+	str_map_free (&self->plugins_by_name);
+	poller_free (&self->poller);
 }
 
 static void
@@ -1690,7 +227,8 @@ irc_send (struct bot_context *ctx, const char *format, ...)
 		fputs ("\"\n", stderr);
 	}
 
-	soft_assert (ctx->irc_fd != -1);
+	if (!soft_assert (ctx->irc_fd != -1))
+		return false;
 
 	va_start (ap, format);
 	struct str str;
@@ -2143,10 +681,8 @@ on_plugin_writable (const struct pollfd *fd, struct plugin_data *plugin)
 	struct str *buf = &plugin->write_buffer;
 	size_t written_total = 0;
 
-	// TODO: see "Advanced Programming in the UNIX Environment" Figure C.19;
-	//   check for any unexpected behaviour that might occur
-	if (fd->revents != POLLOUT)
-		print_debug ("poller fd %d: revents: %d", fd->fd, fd->revents);
+	if (fd->revents & ~(POLLOUT | POLLHUP | POLLERR))
+		print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents);
 
 	while (written_total != buf->len)
 	{
@@ -2157,15 +693,18 @@ on_plugin_writable (const struct pollfd *fd, struct plugin_data *plugin)
 		{
 			if (errno == EAGAIN)
 				break;
+			if (errno == EINTR)
+				continue;
 
-			if (!soft_assert (errno == EINTR) && !plugin->is_zombie)
-			{
-				print_debug ("%s: %s", "recv", strerror (errno));
-				print_error ("failure on writing to plugin `%s',"
-					" therefore I'm unloading it", plugin->name);
-				plugin_zombify (plugin);
-				break;
-			}
+			soft_assert (errno == EPIPE);
+			// Zombies shouldn't get dispatched for writability
+			hard_assert (!plugin->is_zombie);
+
+			print_debug ("%s: %s", "write", strerror (errno));
+			print_error ("failure on writing to plugin `%s',"
+				" therefore I'm unloading it", plugin->name);
+			plugin_zombify (plugin);
+			break;
 		}
 
 		// This may be equivalent to EAGAIN on some implementations
@@ -2301,10 +840,8 @@ plugin_process_message (const struct irc_message *msg,
 static void
 on_plugin_readable (const struct pollfd *fd, struct plugin_data *plugin)
 {
-	// TODO: see "Advanced Programming in the UNIX Environment" Figure C.19;
-	//   check for any unexpected behaviour that might occur
-	if (fd->revents != POLLIN)
-		print_debug ("poller fd %d: revents: %d", fd->fd, fd->revents);
+	if (fd->revents & ~(POLLIN | POLLHUP | POLLERR))
+		print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents);
 
 	// TODO: see if I can reuse irc_fill_read_buffer()
 	struct str *buf = &plugin->read_buffer;
@@ -2818,11 +1355,11 @@ start:
 		buf->alloc - buf->len - 1 /* null byte */);
 
 	const char *error_info = NULL;
-	switch (SSL_get_error (ctx->ssl, n_read))
+	switch (xssl_get_error (ctx->ssl, n_read, &error_info))
 	{
 	case SSL_ERROR_NONE:
 		buf->str[buf->len += n_read] = '\0';
-		return IRC_READ_AGAIN;
+		return IRC_READ_OK;
 	case SSL_ERROR_ZERO_RETURN:
 		return IRC_READ_EOF;
 	case SSL_ERROR_WANT_READ:
@@ -2835,28 +1372,12 @@ start:
 		soft_assert (poll (&pfd, 1, 0) > 0);
 		goto start;
 	}
-	case SSL_ERROR_SYSCALL:
-	{
-		int err;
-		if ((err = ERR_get_error ()))
-			error_info = ERR_error_string (err, NULL);
-		else if (n_read == 0)
-			return IRC_READ_EOF;
-		else
-		{
-			if (errno == EINTR)
-				goto start;
-			error_info = strerror (errno);
-		}
-		break;
-	}
-	case SSL_ERROR_SSL:
+	case XSSL_ERROR_TRY_AGAIN:
+		goto start;
 	default:
-		error_info = ERR_error_string (ERR_get_error (), NULL);
+		print_debug ("%s: %s: %s", __func__, "SSL_read", error_info);
+		return IRC_READ_ERROR;
 	}
-
-	print_debug ("%s: %s: %s", __func__, "SSL_read", error_info);
-	return IRC_READ_ERROR;
 }
 
 static enum irc_read_result
@@ -2975,8 +1496,8 @@ on_irc_disconnected (struct bot_context *ctx)
 static void
 on_irc_readable (const struct pollfd *fd, struct bot_context *ctx)
 {
-	if (fd->revents != POLLIN)
-		print_debug ("poller fd %d: revents: %d", fd->fd, fd->revents);
+	if (fd->revents & ~(POLLIN | POLLHUP | POLLERR))
+		print_debug ("fd %d: unexpected revents: %d", fd->fd, fd->revents);
 
 	(void) set_blocking (ctx->irc_fd, false);
 
@@ -3144,75 +1665,6 @@ on_signal_pipe_readable (const struct pollfd *fd, struct bot_context *ctx)
 }
 
 static void
-write_default_configuration (const char *filename)
-{
-	struct str path, base;
-	int status = EXIT_SUCCESS;
-
-	str_init (&path);
-	str_init (&base);
-
-	if (filename)
-	{
-		char *tmp = xstrdup (filename);
-		str_append (&path, dirname (tmp));
-		strcpy (tmp, filename);
-		str_append (&base, basename (tmp));
-		free (tmp);
-	}
-	else
-	{
-		get_xdg_home_dir (&path, "XDG_CONFIG_HOME", ".config");
-		str_append (&path, "/" PROGRAM_NAME);
-		str_append (&base, PROGRAM_NAME ".conf");
-	}
-
-	struct error *e = NULL;
-	if (!mkdir_with_parents (path.str, &e))
-	{
-		print_fatal ("%s", e->message);
-		status = EXIT_FAILURE;
-		goto out;
-	}
-
-	str_append_c (&path, '/');
-	str_append_str (&path, &base);
-
-	FILE *fp = fopen (path.str, "w");
-	if (!fp)
-	{
-		print_fatal ("could not open `%s' for writing: %s",
-			path.str, strerror (errno));
-		status = EXIT_FAILURE;
-		goto out;
-	}
-
-	errno = 0;
-	for (size_t i = 0; i < N_ELEMENTS (g_config_table); i++)
-	{
-		const struct config_item *item = g_config_table + i;
-		fprintf (fp, "# %s\n", item->description);
-		if (item->default_value)
-			fprintf (fp, "%s=%s\n", item->key, item->default_value);
-		else
-			fprintf (fp, "#%s=\n", item->key);
-	}
-	fclose (fp);
-	if (errno)
-	{
-		print_fatal ("writing to `%s' failed: %s", path.str, strerror (errno));
-		status = EXIT_FAILURE;
-		goto out;
-	}
-	print_status ("configuration written to `%s'", path.str);
-
-out:
-	str_free (&path);
-	str_free (&base);
-	exit (status);
-}
-
-static void
 print_usage (const char *program_name)
 {
 	fprintf (stderr,
@@ -3234,6 +1686,7 @@ main (int argc, char *argv[])
 	str_vector_init (&g_original_argv);
 	str_vector_add_vector (&g_original_argv, argv);
 
+	struct error *e = NULL;
 	static struct option opts[] =
 	{
 		{ "debug",             no_argument,       NULL, 'd' },
@@ -3263,8 +1716,18 @@ main (int argc, char *argv[])
 			printf (PROGRAM_NAME " " PROGRAM_VERSION "\n");
 			exit (EXIT_SUCCESS);
 		case 'w':
-			write_default_configuration (optarg);
-			abort ();
+		{
+			char *filename = write_default_config (optarg, g_config_table, &e);
+			if (!filename)
+			{
+				print_fatal ("%s", e->message);
+				error_free (e);
+				exit (EXIT_FAILURE);
+			}
+			print_status ("configuration written to `%s'", filename);
+			free (filename);
+			exit (EXIT_SUCCESS);
+		}
 		default:
 			print_fatal ("error in options");
 			exit (EXIT_FAILURE);
@@ -3277,12 +1740,12 @@ main (int argc, char *argv[])
 	SSL_library_init ();
 	atexit (EVP_cleanup);
 	SSL_load_error_strings ();
+	// XXX: ERR_load_BIO_strings()?  Anything else?
 	atexit (ERR_free_strings);
 
 	struct bot_context ctx;
 	bot_context_init (&ctx);
 
-	struct error *e = NULL;
 	if (!read_config_file (&ctx.config, &e))
 	{
 		print_fatal ("error loading configuration: %s", e->message);