void
lwan_thread_shutdown(lwan_t *l)
{
lwan_status_debug("Shutting down threads");
for (int i = l->thread.count - 1; i >= 0; i--) {
lwan_thread_t *t = &l->thread.threads[i];
char less_than_int = 0;
lwan_status_debug("Closing epoll for thread %d (fd=%d)", i,
t->epoll_fd);
/* Close the epoll_fd and write less than an int to signal the
* thread to gracefully finish. */
close(t->epoll_fd);
write(t->pipe_fd[1], &less_than_int, sizeof(less_than_int));
}
for (int i = l->thread.count - 1; i >= 0; i--) {
lwan_thread_t *t = &l->thread.threads[i];
lwan_status_debug("Waiting for thread %d to finish", i);
pthread_join(l->thread.threads[i].self, NULL);
lwan_status_debug("Closing pipe (%d, %d)", t->pipe_fd[0],
t->pipe_fd[1]);
close(t->pipe_fd[0]);
close(t->pipe_fd[1]);
}
free(l->thread.threads);
}
void lwan_init_with_config(struct lwan *l, const struct lwan_config *config)
{
/* Load defaults */
memset(l, 0, sizeof(*l));
memcpy(&l->config, config, sizeof(*config));
l->config.listener = dup_or_null(l->config.listener);
l->config.config_file_path = dup_or_null(l->config.config_file_path);
/* Initialize status first, as it is used by other things during
* their initialization. */
lwan_status_init(l);
/* These will only print debugging messages. Debug messages are always
* printed if we're on a debug build, so the quiet setting will be
* respected. */
lwan_job_thread_init();
lwan_tables_init();
try_setup_from_config(l, config);
lwan_response_init(l);
/* Continue initialization as normal. */
lwan_status_debug("Initializing lwan web server");
l->n_cpus = get_number_of_cpus();
if (!l->config.n_threads) {
l->thread.count = l->n_cpus;
if (l->thread.count == 1)
l->thread.count = 2;
} else if (l->config.n_threads > 3 * l->n_cpus) {
l->thread.count = (short unsigned int)(l->n_cpus * 3);
lwan_status_warning("%d threads requested, but only %d online CPUs; "
"capping to %d threads",
l->config.n_threads, l->n_cpus, 3 * l->n_cpus);
} else if (l->config.n_threads > 63) {
l->thread.count = 64;
lwan_status_warning("%d threads requested, but max 64 supported",
l->config.n_threads);
} else {
l->thread.count = l->config.n_threads;
}
rlim_t max_open_files = setup_open_file_count_limits();
allocate_connections(l, (size_t)max_open_files);
l->thread.max_fd = (unsigned)max_open_files / (unsigned)l->thread.count;
lwan_status_info("Using %d threads, maximum %d sockets per thread",
l->thread.count, l->thread.max_fd);
signal(SIGPIPE, SIG_IGN);
lwan_readahead_init();
lwan_thread_init(l);
lwan_socket_init(l);
lwan_http_authorize_init();
lwan_fd_watch_init(l);
}
static void lwan_module_init(lwan_t *l)
{
if (!l->module_registry) {
lwan_status_debug("Initializing module registry");
l->module_registry = hash_str_new(NULL, NULL);
}
}
static void lwan_module_register(lwan_t *l, const lwan_module_t *module)
{
if (!module->name)
lwan_status_critical("Module at %p has no name", module);
lwan_status_debug("Registering module \"%s\"", module->name);
hash_add(l->module_registry, module->name, module);
}
void
lwan_thread_shutdown(lwan_t *l)
{
lwan_status_debug("Shutting down threads");
for (int i = l->thread.count - 1; i >= 0; i--) {
lwan_thread_t *t = &l->thread.threads[i];
char less_than_int = 0;
ssize_t r;
lwan_status_debug("Closing epoll for thread %d (fd=%d)", i,
t->epoll_fd);
/* Close the epoll_fd and write less than an int to signal the
* thread to gracefully finish. */
close(t->epoll_fd);
while (true) {
r = write(t->pipe_fd[1], &less_than_int, sizeof(less_than_int));
if (r >= 0)
break;
if (errno == EAGAIN || errno == EWOULDBLOCK || errno == EINTR)
continue;
lwan_status_error("Could not write to I/O thread (%d) pipe to shutdown", i);
break;
}
}
for (int i = l->thread.count - 1; i >= 0; i--) {
lwan_thread_t *t = &l->thread.threads[i];
lwan_status_debug("Waiting for thread %d to finish", i);
pthread_join(l->thread.threads[i].self, NULL);
lwan_status_debug("Closing pipe (%d, %d)", t->pipe_fd[0],
t->pipe_fd[1]);
close(t->pipe_fd[0]);
close(t->pipe_fd[1]);
}
free(l->thread.threads);
}
void
lwan_init(lwan_t *l)
{
int max_threads = sysconf(_SC_NPROCESSORS_ONLN);
struct rlimit r;
/* Load defaults */
memcpy(&l->config, &default_config, sizeof(default_config));
/* Initialize status first, as it is used by other things during
* their initialization. */
lwan_status_init(l);
/* These will only print debugging messages. Debug messages are always
* printed if we're on a debug build, so the quiet setting will be
* respected. */
lwan_job_thread_init();
lwan_response_init();
lwan_tables_init();
/* Load the configuration file. */
if (!setup_from_config(l))
lwan_status_warning("Could not read config file, using defaults");
/* Continue initialization as normal. */
lwan_status_debug("Initializing lwan web server");
l->thread.count = max_threads > 0 ? max_threads : 2;
if (getrlimit(RLIMIT_NOFILE, &r) < 0)
lwan_status_critical_perror("getrlimit");
if (r.rlim_max == RLIM_INFINITY)
r.rlim_cur *= 8;
else if (r.rlim_cur < r.rlim_max)
r.rlim_cur = r.rlim_max;
if (setrlimit(RLIMIT_NOFILE, &r) < 0)
lwan_status_critical_perror("setrlimit");
l->conns = calloc(r.rlim_cur, sizeof(lwan_connection_t));
l->thread.max_fd = r.rlim_cur / l->thread.count;
lwan_status_info("Using %d threads, maximum %d sockets per thread",
l->thread.count, l->thread.max_fd);
for (--r.rlim_cur; r.rlim_cur; --r.rlim_cur)
l->conns[r.rlim_cur].response_buffer = strbuf_new();
srand(time(NULL));
signal(SIGPIPE, SIG_IGN);
close(STDIN_FILENO);
lwan_thread_init(l);
lwan_socket_init(l);
lwan_http_authorize_init();
}
void
lwan_init_with_config(lwan_t *l, const lwan_config_t *config)
{
/* Load defaults */
memset(l, 0, sizeof(*l));
memcpy(&l->config, config, sizeof(*config));
/* Initialize status first, as it is used by other things during
* their initialization. */
lwan_status_init(l);
/* These will only print debugging messages. Debug messages are always
* printed if we're on a debug build, so the quiet setting will be
* respected. */
lwan_job_thread_init();
lwan_tables_init();
lwan_module_init(l);
/* Load the configuration file. */
if (config == &default_config) {
if (!setup_from_config(l))
lwan_status_warning("Could not read config file, using defaults");
/* `quiet` key might have changed value. */
lwan_status_init(l);
}
lwan_response_init(l);
/* Continue initialization as normal. */
lwan_status_debug("Initializing lwan web server");
if (!l->config.n_threads) {
l->thread.count = get_number_of_cpus();
if (l->thread.count == 1)
l->thread.count = 2;
} else {
l->thread.count = l->config.n_threads;
}
rlim_t max_open_files = setup_open_file_count_limits();
allocate_connections(l, (size_t)max_open_files);
l->thread.max_fd = (unsigned)max_open_files / (unsigned)l->thread.count;
lwan_status_info("Using %d threads, maximum %d sockets per thread",
l->thread.count, l->thread.max_fd);
signal(SIGPIPE, SIG_IGN);
lwan_thread_init(l);
lwan_socket_init(l);
lwan_http_authorize_init();
}
void
lwan_thread_init(lwan_t *l)
{
lwan_status_debug("Initializing threads");
l->thread.threads = calloc((size_t)l->thread.count, sizeof(lwan_thread_t));
if (!l->thread.threads)
lwan_status_critical("Could not allocate memory for threads");
for (short i = 0; i < l->thread.count; i++)
create_thread(l, &l->thread.threads[i]);
}
void lwan_straitjacket_enforce(config_t *c, config_line_t *l)
{
char *user_name = NULL;
char *chroot_path = NULL;
uid_t uid;
gid_t gid;
if (geteuid() != 0) {
config_error(c, "Straitjacket requires root privileges");
return;
}
while (config_read_line(c, l)) {
switch (l->type) {
case CONFIG_LINE_TYPE_LINE:
/* TODO: limit_syscalls */
if (!strcmp(l->line.key, "user")) {
user_name = strdupa(l->line.value);
} else if (!strcmp(l->line.key, "chroot")) {
chroot_path = strdupa(l->line.value);
} else {
config_error(c, "Invalid key: %s", l->line.key);
return;
}
break;
case CONFIG_LINE_TYPE_SECTION:
config_error(c, "Straitjacket accepts no sections");
return;
case CONFIG_LINE_TYPE_SECTION_END:
if (!get_user_uid_gid(user_name, &uid, &gid)) {
config_error(c, "Unknown user: %s", user_name);
return;
}
if (chroot_path) {
if (chroot(chroot_path) < 0) {
lwan_status_critical_perror("Could not chroot() to %s",
chroot_path);
}
lwan_status_debug("Jailed to %s", chroot_path);
}
if (!switch_to_user(uid, gid, user_name)) {
lwan_status_critical("Could not drop privileges to %s, aborting",
user_name);
}
return;
}
}
config_error(c, "Expecting section end while parsing straitjacket");
}
void
lwan_tables_init(void)
{
lwan_status_debug("Initializing tables");
if (mime_types)
return;
mime_types = hash_str_new(NULL, NULL);
if (!mime_types)
return;
size_t i = 0;
for (i = 0; i < N_ELEMENTS(mime_type_array); i++)
hash_add(mime_types, mime_type_array[i].extension,
mime_type_array[i].mime_type);
}
void
lwan_thread_shutdown(lwan_t *l)
{
lwan_status_debug("Shutting down threads");
for (int i = l->thread.count - 1; i >= 0; i--) {
lwan_thread_t *t = &l->thread.threads[i];
/* Closing epoll_fd makes the thread gracefully finish. */
close(t->epoll_fd);
close(t->pipe_fd[0]);
close(t->pipe_fd[1]);
pthread_tryjoin_np(l->thread.threads[i].self, NULL);
}
free(l->thread.threads);
}
static const lwan_module_t *lwan_module_find(lwan_t *l, const char *name)
{
lwan_module_t *module = hash_find(l->module_registry, name);
if (!module) {
lwan_module_t *(*module_fn)(void);
char module_symbol[128];
int r;
for (const char *p = name; *p; p++) {
if (isalnum(*p) || *p == '_')
continue;
lwan_status_error("Module name (%s) contains invalid character: %c",
name, *p);
return NULL;
}
r = snprintf(module_symbol, sizeof(module_symbol),
"lwan_module_%s", name);
if (r < 0 || r >= (int)sizeof(module_symbol)) {
lwan_status_error("Module name too long: %s", name);
return NULL;
}
module_fn = find_handler_symbol(module_symbol);
if (!module_fn) {
lwan_status_error("Module \"%s\" does not exist", name);
return NULL;
}
module = module_fn();
if (!module) {
lwan_status_error("Function \"%s()\" didn't return a module",
module_symbol);
return NULL;
}
lwan_status_debug("Module \"%s\" registered", name);
hash_add(l->module_registry, module->name, module);
}
return module;
}
void lwan_shutdown(struct lwan *l)
{
lwan_status_info("Shutting down");
free(l->config.listener);
free(l->config.error_template);
free(l->config.config_file_path);
lwan_job_thread_shutdown();
lwan_thread_shutdown(l);
lwan_status_debug("Shutting down URL handlers");
lwan_trie_destroy(&l->url_map_trie);
free(l->conns);
lwan_response_shutdown(l);
lwan_tables_shutdown();
lwan_status_shutdown(l);
lwan_http_authorize_shutdown();
}
void
lwan_shutdown(lwan_t *l)
{
lwan_status_info("Shutting down");
if (l->config.listener != default_config.listener)
free(l->config.listener);
lwan_job_thread_shutdown();
lwan_thread_shutdown(l);
lwan_status_debug("Shutting down URL handlers");
lwan_trie_destroy(&l->url_map_trie);
free(l->conns);
lwan_response_shutdown();
lwan_tables_shutdown();
lwan_status_shutdown(l);
lwan_http_authorize_shutdown();
lwan_module_shutdown(l);
}
void
lwan_shutdown(lwan_t *l)
{
lwan_status_info("Shutting down");
lwan_job_thread_shutdown();
lwan_thread_shutdown(l);
lwan_socket_shutdown(l);
lwan_status_debug("Shutting down URL handlers");
lwan_trie_destroy(l->url_map_trie);
int i;
for (i = l->thread.max_fd * l->thread.count - 1; i >= 0; --i)
strbuf_free(l->conns[i].response_buffer);
free(l->conns);
lwan_response_shutdown();
lwan_tables_shutdown();
lwan_status_shutdown(l);
lwan_http_authorize_shutdown();
}
static lwan_connection_t *
grab_and_watch_client(int epoll_fd, int pipe_fd, lwan_connection_t *conns)
{
int fd;
if (UNLIKELY(read(pipe_fd, &fd, sizeof(int)) != sizeof(int)))
return NULL;
struct epoll_event event = {
.events = events_by_write_flag[1],
.data.ptr = &conns[fd]
};
if (UNLIKELY(epoll_ctl(epoll_fd, EPOLL_CTL_ADD, fd, &event) < 0))
return NULL;
return &conns[fd];
}
static void *
thread_io_loop(void *data)
{
lwan_thread_t *t = data;
const int epoll_fd = t->epoll_fd;
const int read_pipe_fd = t->pipe_fd[0];
const int max_events = min((int)t->lwan->thread.max_fd, 1024);
const lwan_t *lwan = t->lwan;
lwan_connection_t *conns = lwan->conns;
struct epoll_event *events;
coro_switcher_t switcher;
struct death_queue_t dq;
int n_fds;
lwan_status_debug("Starting IO loop on thread #%d",
(unsigned short)(ptrdiff_t)(t - t->lwan->thread.threads) + 1);
events = calloc((size_t)max_events, sizeof(*events));
if (UNLIKELY(!events))
lwan_status_critical("Could not allocate memory for events");
death_queue_init(&dq, lwan);
for (;;) {
switch (n_fds = epoll_wait(epoll_fd, events, max_events,
death_queue_epoll_timeout(&dq))) {
case -1:
switch (errno) {
case EBADF:
case EINVAL:
goto epoll_fd_closed;
}
continue;
case 0: /* timeout: shutdown waiting sockets */
death_queue_kill_waiting(&dq);
break;
default: /* activity in some of this poller's file descriptor */
update_date_cache(t);
for (struct epoll_event *ep_event = events; n_fds--; ep_event++) {
lwan_connection_t *conn;
if (!ep_event->data.ptr) {
conn = grab_and_watch_client(epoll_fd, read_pipe_fd, conns);
if (UNLIKELY(!conn))
continue;
spawn_coro(conn, &switcher, &dq);
} else {
conn = ep_event->data.ptr;
if (UNLIKELY(ep_event->events & (EPOLLRDHUP | EPOLLHUP))) {
destroy_coro(&dq, conn);
continue;
}
resume_coro_if_needed(&dq, conn, epoll_fd);
}
death_queue_move_to_last(&dq, conn);
}
}
}
epoll_fd_closed:
death_queue_kill_all(&dq);
free(events);
return NULL;
}
void
lwan_tables_shutdown(void)
{
lwan_status_debug("Shutting down tables");
hash_free(mime_types);
}
