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Diffstat (limited to 'utils.c')
| -rw-r--r-- | utils.c | 1220 |
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); -} |