diff options
Diffstat (limited to 'src/zyklonb.c')
| -rw-r--r-- | src/zyklonb.c | 1673 |
1 files changed, 68 insertions, 1605 deletions
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 (®ex_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); |