Move to liberty

1 files changed, 0 insertions, 1220 deletions

diff --git a/utils.c b/utils.c
deleted file mode 100644
index 600a33b..0000000
--- a/utils.c
+++ /dev/null
@@ -1,1220 +0,0 @@
-/*
- * utils.c: utilities
- *
- * 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 600
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <stdbool.h>
-#include <stdint.h>
-#include <string.h>
-#include <ctype.h>
-#include <locale.h>
-#include <errno.h>
-
-#include <unistd.h>
-#include <sys/stat.h>
-#include <libgen.h>
-#include <iconv.h>
-
-#include <getopt.h>
-#include "siphash.h"
-
-#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)
-
-// --- Logging -----------------------------------------------------------------
-
-static void
-log_message_stdio (void *user_data, const char *quote, const char *fmt,
-	va_list ap)
-{
-	(void) user_data;
-	FILE *stream = stderr;
-
-	fputs (quote, stream);
-	vfprintf (stream, fmt, ap);
-	fputs ("\n", stream);
-}
-
-static void (*g_log_message_real) (void *, const char *, const char *, va_list)
-	= log_message_stdio;
-
-static void
-log_message (void *user_data, const char *quote, const char *fmt, ...)
-	ATTRIBUTE_PRINTF (3, 4);
-
-static void
-log_message (void *user_data, const char *quote, const char *fmt, ...)
-{
-	va_list ap;
-	va_start (ap, fmt);
-	g_log_message_real (user_data, quote, fmt, ap);
-	va_end (ap);
-}
-
-// `fatal' is reserved for unexpected failures that would harm further operation
-
-#ifndef print_fatal_data
-#define print_fatal_data    NULL
-#endif
-
-#ifndef print_error_data
-#define print_error_data    NULL
-#endif
-
-#ifndef print_warning_data
-#define print_warning_data  NULL
-#endif
-
-#ifndef print_status_data
-#define print_status_data   NULL
-#endif
-
-#define print_fatal(...) \
-	log_message (print_fatal_data,   "fatal: ",   __VA_ARGS__)
-#define print_error(...) \
-	log_message (print_error_data,   "error: ",   __VA_ARGS__)
-#define print_warning(...) \
-	log_message (print_warning_data, "warning: ", __VA_ARGS__)
-#define print_status(...) \
-	log_message (print_status_data,  "-- ",       __VA_ARGS__)
-
-#define exit_fatal(...)                                                        \
-	BLOCK_START                                                                \
-		print_fatal (__VA_ARGS__);                                             \
-		exit (EXIT_FAILURE);                                                   \
-	BLOCK_END
-
-// --- 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
-
-#ifndef print_debug_data
-#define print_debug_data   NULL
-#endif
-
-#define print_debug(...)                                                       \
-	BLOCK_START                                                                \
-		if (g_debug_mode)                                                      \
-			log_message (print_debug_data, "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)
-		exit_fatal ("malloc: %s", strerror (errno));
-	return p;
-}
-
-static void *
-xcalloc (size_t n, size_t m)
-{
-	void *p = calloc (n, m);
-	if (!p && n && m)
-		exit_fatal ("calloc: %s", strerror (errno));
-	return p;
-}
-
-static void *
-xrealloc (void *o, size_t n)
-{
-	void *p = realloc (o, n);
-	if (!p && n)
-		exit_fatal ("realloc: %s", strerror (errno));
-	return p;
-}
-
-static void *
-xreallocarray (void *o, size_t n, size_t m)
-{
-	if (m && n > SIZE_MAX / m)
-	{
-		errno = ENOMEM;
-		exit_fatal ("reallocarray: %s", strerror (errno));
-	}
-	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 ----------------------------------------------
-
-#define LIST_HEADER(type)                                                      \
-	struct type *next;                                                         \
-	struct type *prev;
-
-#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
-
-#define LIST_APPEND_WITH_TAIL(head, tail, link)                                \
-	BLOCK_START                                                                \
-		(link)->prev = (tail);                                                 \
-		(link)->next = NULL;                                                   \
-		if ((link)->prev)                                                      \
-			(link)->prev->next = (link);                                       \
-		else                                                                   \
-			(head) = (link);                                                   \
-		(tail) = (link);                                                       \
-	BLOCK_END
-
-#define LIST_UNLINK_WITH_TAIL(head, tail, link)                                \
-	BLOCK_START                                                                \
-		if ((tail) == (link))                                                  \
-			(tail) = (link)->prev;                                             \
-		LIST_UNLINK ((head), (link));                                          \
-	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));
-}
-
-// --- 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
-};
-
-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 void *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;
-}
-
-// --- Errors ------------------------------------------------------------------
-
-// Error reporting utilities.  Inspired by GError, only much simpler.
-
-struct error
-{
-	char *message;                      ///< Textual description of the event
-};
-
-static void
-error_set (struct error **e, const char *message, ...) ATTRIBUTE_PRINTF (2, 3);
-
-static void
-error_set (struct error **e, const char *message, ...)
-{
-	if (!e)
-		return;
-
-	va_list ap;
-	va_start (ap, message);
-	int size = vsnprintf (NULL, 0, message, ap);
-	va_end (ap);
-
-	hard_assert (size >= 0);
-
-	struct error *tmp = xmalloc (sizeof *tmp);
-	tmp->message = xmalloc (size + 1);
-
-	va_start (ap, message);
-	size = vsnprintf (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);
-}
-
-// --- String hash map ---------------------------------------------------------
-
-// The most basic <string, managed pointer> map (or associative array).
-
-struct str_map_link
-{
-	LIST_HEADER (str_map_link)
-
-	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
-
-	/// Callback that transforms all key values for storage and comparison;
-	/// has to behave exactly like strxfrm().
-	size_t (*key_xfrm) (char *dest, const char *src, size_t n);
-};
-
-// As long as you don't remove the current entry, you can modify the map.
-// Use `link' directly to access the data.
-
-struct str_map_iter
-{
-	struct str_map *map;                ///< The map we're iterating
-	size_t next_index;                  ///< Next table index to search
-	struct str_map_link *link;          ///< Current link
-};
-
-#define STR_MAP_MIN_ALLOC 16
-
-typedef void (*str_map_free_fn) (void *);
-
-static void
-str_map_init (struct str_map *self)
-{
-	self->alloc = STR_MAP_MIN_ALLOC;
-	self->len = 0;
-	self->free = NULL;
-	self->key_xfrm = 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 void
-str_map_iter_init (struct str_map_iter *self, struct str_map *map)
-{
-	self->map = map;
-	self->next_index = 0;
-	self->link = NULL;
-}
-
-static void *
-str_map_iter_next (struct str_map_iter *self)
-{
-	struct str_map *map = self->map;
-	if (self->link)
-		self->link = self->link->next;
-	while (!self->link)
-	{
-		if (self->next_index >= map->alloc)
-			return NULL;
-		self->link = map->map[self->next_index++];
-	}
-	return self->link->data;
-}
-
-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_real (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_set (struct str_map *self, const char *key, void *value)
-{
-	if (!self->key_xfrm)
-	{
-		str_map_set_real (self, key, value);
-		return;
-	}
-	char tmp[self->key_xfrm (NULL, key, 0) + 1];
-	self->key_xfrm (tmp, key, sizeof tmp);
-	str_map_set_real (self, tmp, value);
-}
-
-static void *
-str_map_find_real (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, (const char *) iter + sizeof *iter))
-			return iter->data;
-	return NULL;
-}
-
-static void *
-str_map_find (struct str_map *self, const char *key)
-{
-	if (!self->key_xfrm)
-		return str_map_find_real (self, key);
-
-	char tmp[self->key_xfrm (NULL, key, 0) + 1];
-	self->key_xfrm (tmp, key, sizeof tmp);
-	return str_map_find_real (self, tmp);
-}
-
-// --- 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 *xstrdup_printf (const char *format, ...) ATTRIBUTE_PRINTF (1, 2);
-
-static char *
-xstrdup_printf (const char *format, ...)
-{
-	va_list ap;
-	va_start (ap, format);
-	int size = vsnprintf (NULL, 0, format, ap);
-	va_end (ap);
-	if (size < 0)
-		return NULL;
-
-	char buf[size + 1];
-	va_start (ap, format);
-	size = vsnprintf (buf, sizeof buf, format, ap);
-	va_end (ap);
-	if (size < 0)
-		return NULL;
-
-	return xstrdup (buf);
-}
-
-static char *
-iconv_xstrdup (iconv_t conv, char *in, size_t in_len, size_t *out_len)
-{
-	char *buf, *buf_ptr;
-	size_t out_left, buf_alloc;
-
-	buf = buf_ptr = xmalloc (out_left = buf_alloc = 64);
-
-	char *in_ptr = in;
-	if (in_len == (size_t) -1)
-		in_len = strlen (in) + 1;
-
-	while (iconv (conv, (char **) &in_ptr, &in_len,
-		(char **) &buf_ptr, &out_left) == (size_t) -1)
-	{
-		if (errno != E2BIG)
-		{
-			free (buf);
-			return NULL;
-		}
-		out_left += buf_alloc;
-		char *new_buf = xrealloc (buf, buf_alloc <<= 1);
-		buf_ptr += new_buf - buf;
-		buf = new_buf;
-	}
-	if (out_len)
-		*out_len = buf_alloc - out_left;
-	return buf;
-}
-
-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 void
-get_xdg_config_dirs (struct str_vector *out)
-{
-	struct str config_home;
-	str_init (&config_home);
-	get_xdg_home_dir (&config_home, "XDG_CONFIG_HOME", ".config");
-	str_vector_add (out, config_home.str);
-	str_free (&config_home);
-
-	const char *xdg_config_dirs;
-	if ((xdg_config_dirs = getenv ("XDG_CONFIG_DIRS")))
-		split_str_ignore_empty (xdg_config_dirs, ':', out);
-}
-
-static char *
-resolve_config_filename (const char *filename)
-{
-	// Absolute path is absolute
-	if (*filename == '/')
-		return xstrdup (filename);
-
-	struct str_vector paths;
-	str_vector_init (&paths);
-	get_xdg_config_dirs (&paths);
-
-	struct str file;
-	str_init (&file);
-
-	char *result = NULL;
-	for (unsigned i = 0; i < paths.len; i++)
-	{
-		// As per spec, relative paths are ignored
-		if (*paths.vector[i] != '/')
-			continue;
-
-		str_reset (&file);
-		str_append_printf (&file, "%s/" PROGRAM_NAME "/%s",
-			paths.vector[i], filename);
-
-		struct stat st;
-		if (!stat (file.str, &st))
-		{
-			result = str_steal (&file);
-			break;
-		}
-	}
-
-	str_vector_free (&paths);
-	str_free (&file);
-	return result;
-}
-
-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, "cannot create directory `%s': %s",
-				path, strerror (errno));
-			return false;
-		}
-	}
-	else if (!S_ISDIR (st.st_mode))
-	{
-		error_set (e, "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
-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;
-}
-
-// --- Configuration -----------------------------------------------------------
-
-// The keys are stripped of surrounding whitespace, the values are not.
-
-struct config_item
-{
-	const char *key;
-	const char *default_value;
-	const char *description;
-};
-
-static bool
-read_config_file (struct str_map *config, struct error **e)
-{
-	char *filename = resolve_config_filename (PROGRAM_NAME ".conf");
-	if (!filename)
-		return true;
-
-	FILE *fp = fopen (filename, "r");
-	if (!fp)
-	{
-		error_set (e, "could not open `%s' for reading: %s",
-			filename, strerror (errno));
-		free (filename);
-		return false;
-	}
-
-	struct str line;
-	str_init (&line);
-
-	bool errors = false;
-	for (unsigned 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)
-		{
-			char *value = end + 1;
-			do
-				*end = '\0';
-			while (isspace (*--end));
-
-			str_map_set (config, start, xstrdup (value));
-		}
-		else if (*start)
-		{
-			error_set (e, "line %u in config: %s", line_no, "malformed input");
-			errors = true;
-			break;
-		}
-	}
-
-	str_free (&line);
-	fclose (fp);
-	free (filename);
-	return !errors;
-}
-
-static char *
-write_default_config (const char *filename, const char *prolog,
-	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, "could not open `%s' for writing: %s",
-			path.str, strerror (errno));
-		goto error;
-	}
-
-	if (prolog)
-		fputs (prolog, fp);
-
-	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, "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;
-
-}
-
-static void
-call_write_default_config (const char *hint, const struct config_item *table)
-{
-	static const char *prolog =
-	"# " PROGRAM_NAME " " PROGRAM_VERSION " configuration file\n"
-	"#\n"
-	"# Relative paths are searched for in ${XDG_CONFIG_HOME:-~/.config}\n"
-	"# /" PROGRAM_NAME " as well as in $XDG_CONFIG_DIRS/" PROGRAM_NAME "\n"
-	"\n";
-
-	struct error *e = NULL;
-	char *filename = write_default_config (hint, prolog, table, &e);
-	if (!filename)
-	{
-		print_error ("%s", e->message);
-		error_free (e);
-		exit (EXIT_FAILURE);
-	}
-	print_status ("configuration written to `%s'", filename);
-	free (filename);
-}
-
-// --- Option handler ----------------------------------------------------------
-
-// Simple wrapper for the getopt_long API to make it easier to use and maintain.
-
-#define OPT_USAGE_ALIGNMENT_COLUMN 30   ///< Alignment for option descriptions
-
-enum
-{
-	OPT_OPTIONAL_ARG  = (1 << 0),       ///< The argument is optional
-	OPT_LONG_ONLY     = (1 << 1)        ///< Ignore the short name in opt_string
-};
-
-// All options need to have both a short name, and a long name.  The short name
-// is what is returned from opt_handler_get().  It is possible to define a value
-// completely out of the character range combined with the OPT_LONG_ONLY flag.
-//
-// When `arg_hint' is defined, the option is assumed to have an argument.
-
-struct opt
-{
-	int short_name;                     ///< The single-letter name
-	const char *long_name;              ///< The long name
-	const char *arg_hint;               ///< Option argument hint
-	int flags;                          ///< Option flags
-	const char *description;            ///< Option description
-};
-
-struct opt_handler
-{
-	int argc;                           ///< The number of program arguments
-	char **argv;                        ///< Program arguments
-
-	const char *arg_hint;               ///< Program arguments hint
-	const char *description;            ///< Description of the program
-
-	const struct opt *opts;             ///< The list of options
-	size_t opts_len;                    ///< The length of the option array
-
-	struct option *options;             ///< The list of options for getopt
-	char *opt_string;                   ///< The `optstring' for getopt
-};
-
-static void
-opt_handler_free (struct opt_handler *self)
-{
-	free (self->options);
-	free (self->opt_string);
-}
-
-static void
-opt_handler_init (struct opt_handler *self, int argc, char **argv,
-	const struct opt *opts, const char *arg_hint, const char *description)
-{
-	memset (self, 0, sizeof *self);
-	self->argc = argc;
-	self->argv = argv;
-	self->arg_hint = arg_hint;
-	self->description = description;
-
-	size_t len = 0;
-	for (const struct opt *iter = opts; iter->long_name; iter++)
-		len++;
-
-	self->opts = opts;
-	self->opts_len = len;
-	self->options = xcalloc (len + 1, sizeof *self->options);
-
-	struct str opt_string;
-	str_init (&opt_string);
-
-	for (size_t i = 0; i < len; i++)
-	{
-		const struct opt *opt = opts + i;
-		struct option *mapped = self->options + i;
-
-		mapped->name = opt->long_name;
-		if (!opt->arg_hint)
-			mapped->has_arg = no_argument;
-		else if (opt->flags & OPT_OPTIONAL_ARG)
-			mapped->has_arg = optional_argument;
-		else
-			mapped->has_arg = required_argument;
-		mapped->val = opt->short_name;
-
-		if (opt->flags & OPT_LONG_ONLY)
-			continue;
-
-		str_append_c (&opt_string, opt->short_name);
-		if (opt->arg_hint)
-		{
-			str_append_c (&opt_string, ':');
-			if (opt->flags & OPT_OPTIONAL_ARG)
-				str_append_c (&opt_string, ':');
-		}
-	}
-
-	self->opt_string = str_steal (&opt_string);
-}
-
-static void
-opt_handler_usage (struct opt_handler *self, FILE *stream)
-{
-	struct str usage;
-	str_init (&usage);
-
-	str_append_printf (&usage, "Usage: %s [OPTION]... %s\n",
-		self->argv[0], self->arg_hint ? self->arg_hint : "");
-	str_append_printf (&usage, "%s\n\n", self->description);
-
-	for (size_t i = 0; i < self->opts_len; i++)
-	{
-		struct str row;
-		str_init (&row);
-
-		const struct opt *opt = self->opts + i;
-		if (!(opt->flags & OPT_LONG_ONLY))
-			str_append_printf (&row, "  -%c, ", opt->short_name);
-		else
-			str_append (&row, "      ");
-		str_append_printf (&row, "--%s", opt->long_name);
-		if (opt->arg_hint)
-			str_append_printf (&row, (opt->flags & OPT_OPTIONAL_ARG)
-				? " [%s]" : " %s", opt->arg_hint);
-
-		// TODO: keep the indent if there are multiple lines
-		if (row.len + 2 <= OPT_USAGE_ALIGNMENT_COLUMN)
-		{
-			str_append (&row, "  ");
-			str_append_printf (&usage, "%-*s%s\n",
-				OPT_USAGE_ALIGNMENT_COLUMN, row.str, opt->description);
-		}
-		else
-			str_append_printf (&usage, "%s\n%-*s%s\n", row.str,
-				OPT_USAGE_ALIGNMENT_COLUMN, "", opt->description);
-
-		str_free (&row);
-	}
-
-	fputs (usage.str, stream);
-	str_free (&usage);
-}
-
-static int
-opt_handler_get (struct opt_handler *self)
-{
-	return getopt_long (self->argc, self->argv,
-		self->opt_string, self->options, NULL);
-}