void
lws_free_wsi(struct lws *wsi)
{
if (!wsi)
return;
/* Protocol user data may be allocated either internally by lws
* or by specified the user.
* We should only free what we allocated. */
if (wsi->protocol && wsi->protocol->per_session_data_size &&
wsi->user_space && !wsi->user_space_externally_allocated)
lws_free(wsi->user_space);
lws_free_set_NULL(wsi->rxflow_buffer);
lws_free_set_NULL(wsi->trunc_alloc);
if (wsi->u.hdr.ah)
/* we're closing, losing some rx is OK */
wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
/* we may not have an ah, but may be on the waiting list... */
lws_header_table_detach(wsi, 0);
wsi->context->count_wsi_allocated--;
lwsl_debug("%s: %p, remaining wsi %d\n", __func__, wsi,
wsi->context->count_wsi_allocated);
lws_free(wsi);
}
void
lws_free_wsi(struct lws *wsi)
{
if (!wsi)
return;
/* Protocol user data may be allocated either internally by lws
* or by specified the user.
* We should only free what we allocated. */
if (wsi->protocol && wsi->protocol->per_session_data_size &&
wsi->user_space && !wsi->user_space_externally_allocated)
lws_free(wsi->user_space);
lws_free_set_NULL(wsi->rxflow_buffer);
lws_free_set_NULL(wsi->trunc_alloc);
/*
* These union members have an ah at the start
*
* struct _lws_http_mode_related http;
* struct _lws_http2_related http2;
* struct _lws_header_related hdr;
*
* basically ws-related union member does not
*/
if (wsi->mode != LWSCM_WS_CLIENT &&
wsi->mode != LWSCM_WS_SERVING)
if (wsi->u.hdr.ah)
lws_free_header_table(wsi);
lws_free(wsi);
}
int
lws_access_log(struct lws *wsi)
{
char *p = wsi->http.access_log.user_agent, ass[512],
*p1 = wsi->http.access_log.referrer;
int l;
if (!wsi->vhost)
return 0;
if (wsi->vhost->log_fd == (int)LWS_INVALID_FILE)
return 0;
if (!wsi->access_log_pending)
return 0;
if (!wsi->http.access_log.header_log)
return 0;
if (!p)
p = "";
if (!p1)
p1 = "";
/*
* We do this in two parts to restrict an oversize referrer such that
* we will always have space left to append an empty useragent, while
* maintaining the structure of the log text
*/
l = lws_snprintf(ass, sizeof(ass) - 7, "%s %d %lu \"%s",
wsi->http.access_log.header_log,
wsi->http.access_log.response, wsi->http.access_log.sent, p1);
if (strlen(p) > sizeof(ass) - 6 - l)
p[sizeof(ass) - 6 - l] = '\0';
l += lws_snprintf(ass + l, sizeof(ass) - 1 - l, "\" \"%s\"\n", p);
if (write(wsi->vhost->log_fd, ass, l) != l)
lwsl_err("Failed to write log\n");
if (wsi->http.access_log.header_log) {
lws_free(wsi->http.access_log.header_log);
wsi->http.access_log.header_log = NULL;
}
if (wsi->http.access_log.user_agent) {
lws_free(wsi->http.access_log.user_agent);
wsi->http.access_log.user_agent = NULL;
}
if (wsi->http.access_log.referrer) {
lws_free(wsi->http.access_log.referrer);
wsi->http.access_log.referrer = NULL;
}
wsi->access_log_pending = 0;
return 0;
}
int
lws_plat_inet_pton(int af, const char *src, void *dst)
{
WCHAR *buffer;
DWORD bufferlen = (int)strlen(src) + 1;
BOOL ok = FALSE;
buffer = lws_malloc(bufferlen * 2, "inet_pton");
if (!buffer) {
lwsl_err("Out of memory\n");
return -1;
}
if (MultiByteToWideChar(CP_ACP, 0, src, bufferlen, buffer, bufferlen) <= 0) {
lwsl_err("Failed to convert multi byte to wide char\n");
lws_free(buffer);
return -1;
}
if (af == AF_INET) {
struct sockaddr_in dstaddr;
int dstaddrlen = sizeof(dstaddr);
bzero(&dstaddr, sizeof(dstaddr));
dstaddr.sin_family = AF_INET;
if (!WSAStringToAddressW(buffer, af, 0, (struct sockaddr *) &dstaddr, &dstaddrlen)) {
ok = TRUE;
memcpy(dst, &dstaddr.sin_addr, sizeof(dstaddr.sin_addr));
}
#ifdef LWS_WITH_IPV6
} else if (af == AF_INET6) {
struct sockaddr_in6 dstaddr;
int dstaddrlen = sizeof(dstaddr);
bzero(&dstaddr, sizeof(dstaddr));
dstaddr.sin6_family = AF_INET6;
if (!WSAStringToAddressW(buffer, af, 0, (struct sockaddr *) &dstaddr, &dstaddrlen)) {
ok = TRUE;
memcpy(dst, &dstaddr.sin6_addr, sizeof(dstaddr.sin6_addr));
}
#endif
} else
lwsl_err("Unsupported type\n");
if (!ok) {
int rv = WSAGetLastError();
lwsl_err("WSAAddressToString() : %d\n", rv);
}
lws_free(buffer);
return ok ? 1 : -1;
}
int alloc_file(struct lws_context *context, const char *filename, uint8_t **buf,
lws_filepos_t *amount)
{
nvs_handle nvh;
size_t s;
int n = 0;
ESP_ERROR_CHECK(nvs_open("lws-station", NVS_READWRITE, &nvh));
if (nvs_get_blob(nvh, filename, NULL, &s) != ESP_OK) {
n = 1;
goto bail;
}
*buf = lws_malloc(s, "alloc_file");
if (!*buf) {
n = 2;
goto bail;
}
if (nvs_get_blob(nvh, filename, (char *)*buf, &s) != ESP_OK) {
lws_free(*buf);
n = 1;
goto bail;
}
*amount = s;
bail:
nvs_close(nvh);
return n;
}
void
lws_libuv_destroyloop(struct lws_context *context, int tsi)
{
struct lws_context_per_thread *pt = &context->pt[tsi];
int m;
if (!(context->options & LWS_SERVER_OPTION_LIBUV))
return;
if (!pt->io_loop_uv)
return;
if (context->use_ev_sigint)
uv_signal_stop(&pt->w_sigint.uv_watcher);
for (m = 0; m < ARRAY_SIZE(sigs); m++)
uv_signal_stop(&pt->signals[m]);
if (!pt->ev_loop_foreign) {
uv_stop(pt->io_loop_uv);
uv_walk(pt->io_loop_uv, lws_uv_walk_cb, NULL);
while (uv_run(pt->io_loop_uv, UV_RUN_NOWAIT));
m = uv_loop_close(pt->io_loop_uv);
if (m == UV_EBUSY)
lwsl_debug("%s: uv_loop_close: UV_EBUSY\n", __func__);
lws_free(pt->io_loop_uv);
}
}
static void
lws_libuv_closewsi_m(uv_handle_t* handle)
{
lws_sockfd_type sockfd = (lws_sockfd_type)(lws_intptr_t)handle->data;
lwsl_debug("%s: sockfd %d\n", __func__, sockfd);
compatible_close(sockfd);
lws_free(handle);
}
LWS_VISIBLE void
lws_plat_context_early_destroy(struct libwebsocket_context *context)
{
if (context->events) {
WSACloseEvent(context->events[0]);
lws_free(context->events);
}
}
static struct lws *
lws_adopt_socket_vhost(struct lws_vhost *vh, lws_sockfd_type accept_fd)
{
struct lws_context *context = vh->context;
struct lws *new_wsi = lws_create_new_server_wsi(vh);
if (!new_wsi) {
compatible_close(accept_fd);
return NULL;
}
lwsl_info("%s: new wsi %p, sockfd %d\n", __func__, new_wsi, accept_fd);
new_wsi->sock = accept_fd;
/* the transport is accepted... give him time to negotiate */
lws_set_timeout(new_wsi, PENDING_TIMEOUT_ESTABLISH_WITH_SERVER,
context->timeout_secs);
#if LWS_POSIX == 0
mbed3_tcp_stream_accept(accept_fd, new_wsi);
#endif
/*
* A new connection was accepted. Give the user a chance to
* set properties of the newly created wsi. There's no protocol
* selected yet so we issue this to protocols[0]
*/
if ((context->vhost_list->protocols[0].callback)(new_wsi,
LWS_CALLBACK_SERVER_NEW_CLIENT_INSTANTIATED, NULL, NULL, 0)) {
compatible_close(new_wsi->sock);
lws_free(new_wsi);
return NULL;
}
lws_libev_accept(new_wsi, new_wsi->sock);
lws_libuv_accept(new_wsi, new_wsi->sock);
if (!LWS_SSL_ENABLED(new_wsi->vhost)) {
if (insert_wsi_socket_into_fds(context, new_wsi)) {
lwsl_err("%s: fail inserting socket\n", __func__);
goto fail;
}
} else {
new_wsi->mode = LWSCM_SSL_INIT;
if (lws_server_socket_service_ssl(new_wsi, accept_fd)) {
lwsl_err("%s: fail ssl negotiation\n", __func__);
goto fail;
}
}
return new_wsi;
fail:
lws_close_free_wsi(new_wsi, LWS_CLOSE_STATUS_NOSTATUS);
return NULL;
}
void
lws_struct_json_serialize_destroy(lws_struct_serialize_t **pjs)
{
if (!*pjs)
return;
lws_free(*pjs);
*pjs = NULL;
}
LWS_VISIBLE void
lws_plat_context_late_destroy(struct lws_context *context)
{
if (context->lws_lookup)
lws_free(context->lws_lookup);
close(context->dummy_pipe_fds[0]);
close(context->dummy_pipe_fds[1]);
close(context->fd_random);
}
void
lws_libuv_destroyloop(struct lws_context *context, int tsi)
{
struct lws_context_per_thread *pt = &context->pt[tsi];
// struct lws_context *ctx;
int m, budget = 100, ns;
if (!lws_check_opt(context->options, LWS_SERVER_OPTION_LIBUV))
return;
if (!pt->io_loop_uv)
return;
lwsl_notice("%s: closing signals + timers context %p\n", __func__, context);
if (context->use_ev_sigint) {
uv_signal_stop(&pt->w_sigint.uv_watcher);
ns = ARRAY_SIZE(sigs);
if (lws_check_opt(context->options, LWS_SERVER_OPTION_UV_NO_SIGSEGV_SIGFPE_SPIN))
ns = 2;
for (m = 0; m < ns; m++) {
uv_signal_stop(&pt->signals[m]);
uv_close((uv_handle_t *)&pt->signals[m], lws_uv_close_cb);
}
}
uv_timer_stop(&pt->uv_timeout_watcher);
uv_close((uv_handle_t *)&pt->uv_timeout_watcher, lws_uv_close_cb);
uv_idle_stop(&pt->uv_idle);
uv_close((uv_handle_t *)&pt->uv_idle, lws_uv_close_cb);
if (pt->ev_loop_foreign)
return;
while (budget-- && uv_run(pt->io_loop_uv, UV_RUN_NOWAIT))
;
lwsl_notice("%s: closing all loop handles context %p\n", __func__, context);
uv_stop(pt->io_loop_uv);
uv_walk(pt->io_loop_uv, lws_uv_walk_cb, NULL);
while (uv_run(pt->io_loop_uv, UV_RUN_NOWAIT))
;
#if UV_VERSION_MAJOR > 0
m = uv_loop_close(pt->io_loop_uv);
if (m == UV_EBUSY)
lwsl_err("%s: uv_loop_close: UV_EBUSY\n", __func__);
#endif
lws_free(pt->io_loop_uv);
}
LWS_VISIBLE void
lws_plat_context_late_destroy(struct lws_context *context)
{
#ifdef LWS_WITH_PLUGINS
if (context->plugin_list)
lws_plat_plugins_destroy(context);
#endif
if (context->lws_lookup)
lws_free(context->lws_lookup);
}
int alloc_pem_to_der_file(struct lws_context *context, const char *filename, uint8_t **buf,
lws_filepos_t *amount)
{
uint8_t *pem, *p, *q, *end;
lws_filepos_t len;
int n;
n = alloc_file(context, filename, &pem, &len);
if (n)
return n;
/* trim the first line */
p = pem;
end = p + len;
if (strncmp((char *)p, "-----", 5))
goto bail;
p += 5;
while (p < end && *p != '\n' && *p != '-')
p++;
if (*p != '-')
goto bail;
while (p < end && *p != '\n')
p++;
if (p >= end)
goto bail;
p++;
/* trim the last line */
q = end - 2;
while (q > pem && *q != '\n')
q--;
if (*q != '\n')
goto bail;
*q = '\0';
*amount = lws_b64_decode_string((char *)p, (char *)pem, len);
*buf = pem;
return 0;
bail:
lws_free(pem);
return 4;
}
LWS_VISIBLE void
lws_plat_context_late_destroy(struct lws_context *context)
{
int n;
for (n = 0; n < FD_HASHTABLE_MODULUS; n++) {
if (context->fd_hashtable[n].wsi)
lws_free(context->fd_hashtable[n].wsi);
}
WSACleanup();
}
void
lws_free_wsi(struct libwebsocket *wsi)
{
if (!wsi)
return;
/* Protocol user data may be allocated either internally by lws
* or by specified the user. Important we don't free external user data */
if (wsi->protocol && wsi->protocol->per_session_data_size
&& wsi->user_space && !wsi->user_space_externally_allocated) {
lws_free(wsi->user_space);
}
lws_free2(wsi->rxflow_buffer);
lws_free2(wsi->truncated_send_malloc);
// TODO: Probably should handle the union structs in wsi->u here depending
// on connection mode as well. Too spaghetti for me to follow however...
lws_free_header_table(wsi);
lws_free(wsi);
}
LWS_VISIBLE void
lws_plat_context_early_destroy(struct lws_context *context)
{
struct lws_context_per_thread *pt = &context->pt[0];
int n = context->count_threads;
while (n--) {
if (pt->events) {
WSACloseEvent(pt->events[0]);
lws_free(pt->events);
}
pt++;
}
}
void
lws_free_wsi(struct lws *wsi)
{
if (!wsi)
return;
/* Protocol user data may be allocated either internally by lws
* or by specified the user.
* We should only free what we allocated. */
if (wsi->protocol
&& wsi->protocol->per_session_data_size
&& wsi->user_space
&& !wsi->user_space_externally_allocated)
{
lws_free(wsi->user_space);
wsi->user_space = NULL;
}
lws_free2(wsi->rxflow_buffer);
lws_free2(wsi->truncated_send_malloc);
lws_free_header_table(wsi);
lws_free(wsi);
}
int alloc_file(struct lws_context *context, const char *filename, uint8_t **buf,
lws_filepos_t *amount)
{
FILE *f;
size_t s;
int n = 0;
f = fopen(filename, "rb");
if (f == NULL) {
n = 1;
goto bail;
}
if (fseek(f, 0, SEEK_END) != 0) {
n = 1;
goto bail;
}
s = ftell(f);
if (s == -1) {
n = 1;
goto bail;
}
if (fseek(f, 0, SEEK_SET) != 0) {
n = 1;
goto bail;
}
*buf = lws_malloc(s, "alloc_file");
if (!*buf) {
n = 2;
goto bail;
}
if (fread(*buf, s, 1, f) != 1) {
lws_free(*buf);
n = 1;
goto bail;
}
*amount = s;
bail:
if (f)
fclose(f);
return n;
}
struct libwebsocket *
libwebsocket_create_new_server_wsi(struct libwebsocket_context *context)
{
struct libwebsocket *new_wsi;
new_wsi = lws_zalloc(sizeof(struct libwebsocket));
if (new_wsi == NULL) {
lwsl_err("Out of memory for new connection\n");
return NULL;
}
new_wsi->pending_timeout = NO_PENDING_TIMEOUT;
new_wsi->rxflow_change_to = LWS_RXFLOW_ALLOW;
/* intialize the instance struct */
new_wsi->state = WSI_STATE_HTTP;
new_wsi->mode = LWS_CONNMODE_HTTP_SERVING;
new_wsi->hdr_parsing_completed = 0;
#ifdef LWS_OPENSSL_SUPPORT
new_wsi->use_ssl = LWS_SSL_ENABLED(context);
#endif
if (lws_allocate_header_table(new_wsi)) {
lws_free(new_wsi);
return NULL;
}
/*
* these can only be set once the protocol is known
* we set an unestablished connection's protocol pointer
* to the start of the supported list, so it can look
* for matching ones during the handshake
*/
new_wsi->protocol = context->protocols;
new_wsi->user_space = NULL;
new_wsi->ietf_spec_revision = 0;
new_wsi->sock = LWS_SOCK_INVALID;
/*
* outermost create notification for wsi
* no user_space because no protocol selection
*/
context->protocols[0].callback(context, new_wsi,
LWS_CALLBACK_WSI_CREATE, NULL, NULL, 0);
return new_wsi;
}
void
lws_ssl_SSL_CTX_destroy(struct lws_vhost *vhost)
{
if (vhost->ssl_ctx) {
#if defined(LWS_USE_POLARSSL)
lws_free(vhost->ssl_ctx);
#else
#if defined(LWS_USE_MBEDTLS)
#else
SSL_CTX_free(vhost->ssl_ctx);
#endif
#endif
}
if (!vhost->user_supplied_ssl_ctx && vhost->ssl_client_ctx) {
#if defined(LWS_USE_POLARSSL)
lws_free(vhost->ssl_client_ctx);
#else
#if defined(LWS_USE_MBEDTLS)
#else
SSL_CTX_free(vhost->ssl_client_ctx);
#endif
#endif
}
}
LWS_VISIBLE LWS_EXTERN void
lws_ring_destroy(struct lws_ring *ring)
{
if (ring->destroy_element)
while (ring->oldest_tail != ring->head) {
ring->destroy_element((uint8_t *)ring->buf +
ring->oldest_tail);
ring->oldest_tail =
(ring->oldest_tail + ring->element_len) %
ring->buflen;
}
if (ring->buf)
lws_free_set_NULL(ring->buf);
lws_free(ring);
}
LWS_VISIBLE void
lws_plat_context_late_destroy(struct lws_context *context)
{
struct lws_context_per_thread *pt = &context->pt[0];
int m = context->count_threads;
if (context->lws_lookup)
lws_free(context->lws_lookup);
while (m--) {
close(pt->dummy_pipe_fds[0]);
close(pt->dummy_pipe_fds[1]);
pt++;
}
close(context->fd_random);
}
static int
lws_urldecode_s_destroy(struct lws_urldecode_stateful *s)
{
int ret = 0;
if (s->state != US_IDLE)
ret = -1;
if (!ret)
if (s->output(s->data, s->name, &s->out, s->pos, 1))
ret = -1;
lws_free(s);
return ret;
}
struct lws *
lws_create_server_child_wsi(struct lws_vhost *vhost, struct lws *parent_wsi,
unsigned int sid)
{
struct lws *wsi = lws_create_new_server_wsi(vhost);
if (!wsi)
return NULL;
/* no more children allowed by parent */
if (parent_wsi->u.http2.child_count + 1 ==
parent_wsi->u.http2.peer_settings.setting[
LWS_HTTP2_SETTINGS__MAX_CONCURRENT_STREAMS])
goto bail;
lws_http2_init(&wsi->u.http2.peer_settings);
lws_http2_init(&wsi->u.http2.my_settings);
wsi->u.http2.stream_id = sid;
wsi->u.http2.my_stream_id = sid;
wsi->u.http2.parent_wsi = parent_wsi;
wsi->u.http2.next_child_wsi = parent_wsi->u.http2.next_child_wsi;
parent_wsi->u.http2.next_child_wsi = wsi;
parent_wsi->u.http2.child_count++;
wsi->u.http2.my_priority = 16;
wsi->u.http2.tx_credit = 65535;
wsi->state = LWSS_HTTP2_ESTABLISHED;
wsi->mode = parent_wsi->mode;
wsi->protocol = &vhost->protocols[0];
if (lws_ensure_user_space(wsi))
goto bail;
lwsl_info("%s: %p new child %p, sid %d, user_space=%p\n", __func__,
parent_wsi, wsi, sid, wsi->user_space);
return wsi;
bail:
vhost->protocols[0].callback(wsi, LWS_CALLBACK_WSI_DESTROY,
NULL, NULL, 0);
lws_free(wsi);
return NULL;
}
LWS_VISIBLE const char *
lws_plat_inet_ntop(int af, const void *src, char *dst, int cnt)
{
WCHAR *buffer;
DWORD bufferlen = cnt;
BOOL ok = FALSE;
buffer = lws_malloc(bufferlen);
if (!buffer) {
lwsl_err("Out of memory\n");
return NULL;
}
if (af == AF_INET) {
struct sockaddr_in srcaddr;
bzero(&srcaddr, sizeof(srcaddr));
srcaddr.sin_family = AF_INET;
memcpy(&(srcaddr.sin_addr), src, sizeof(srcaddr.sin_addr));
if (!WSAAddressToStringW((struct sockaddr*)&srcaddr, sizeof(srcaddr), 0, buffer, &bufferlen))
ok = TRUE;
#ifdef LWS_USE_IPV6
} else if (af == AF_INET6) {
struct sockaddr_in6 srcaddr;
bzero(&srcaddr, sizeof(srcaddr));
srcaddr.sin6_family = AF_INET6;
memcpy(&(srcaddr.sin6_addr), src, sizeof(srcaddr.sin6_addr));
if (!WSAAddressToStringW((struct sockaddr*)&srcaddr, sizeof(srcaddr), 0, buffer, &bufferlen))
ok = TRUE;
#endif
} else
lwsl_err("Unsupported type\n");
if (!ok) {
int rv = WSAGetLastError();
lwsl_err("WSAAddressToString() : %d\n", rv);
} else {
if (WideCharToMultiByte(CP_ACP, 0, buffer, bufferlen, dst, cnt, 0, NULL) <= 0)
ok = FALSE;
}
lws_free(buffer);
return ok ? dst : NULL;
}
LWS_VISIBLE void
lws_plat_context_late_destroy(struct lws_context *context)
{
struct lws_context_per_thread *pt = &context->pt[0];
int m = context->count_threads;
#ifdef LWS_WITH_PLUGINS
if (context->plugin_list)
lws_plat_plugins_destroy(context);
#endif
if (context->lws_lookup)
lws_free(context->lws_lookup);
while (m--) {
close(pt->dummy_pipe_fds[0]);
close(pt->dummy_pipe_fds[1]);
pt++;
}
close(context->fd_random);
}
LWS_VISIBLE int
lws_plat_change_pollfd(struct lws_context *context,
struct lws *wsi, struct lws_pollfd *pfd)
{
void *p;
//lwsl_notice("%s: %p: wsi->pift=%d, events %d\n",
// __func__, wsi, wsi->position_in_fds_table, pfd->events);
if (pfd->events & LWS_POLLIN) {
if (wsi->premature_rx) {
lwsl_notice("replaying buffered rx: wsi %p\n", wsi);
p = wsi->premature_rx;
wsi->premature_rx = NULL;
esp8266_cb_rx(wsi->desc.sockfd,
(char *)p + wsi->prem_rx_pos,
wsi->prem_rx_size - wsi->prem_rx_pos);
wsi->prem_rx_size = 0;
wsi->prem_rx_pos = 0;
lws_free(p);
}
if (espconn_recv_unhold(wsi->desc.sockfd) < 0)
return -1;
} else
if (espconn_recv_hold(wsi->desc.sockfd) < 0)
return -1;
if (!(pfd->events & LWS_POLLOUT))
return 0;
if (!wsi->pending_send_completion) {
pfd->revents |= LWS_POLLOUT;
// lwsl_notice("doing POLLOUT\n");
lws_service_fd(lws_get_context(wsi), pfd);
} //else
//lwsl_notice("pending sc\n");
return 0;
}
void
freeifaddrs(struct ifaddrs *ifp)
{
struct ifaddrs *p, *q;
for (p = ifp; p; ) {
lws_free(p->ifa_name);
lws_free(p->ifa_addr);
lws_free(p->ifa_dstaddr);
lws_free(p->ifa_netmask);
lws_free(p->ifa_data);
q = p;
p = p->ifa_next;
lws_free(q);
}
}
LWS_VISIBLE LWS_EXTERN struct lws_ring *
lws_ring_create(size_t element_len, size_t count,
void (*destroy_element)(void *))
{
struct lws_ring *ring = lws_malloc(sizeof(*ring), "ring create");
if (!ring)
return NULL;
ring->buflen = (uint32_t)(count * element_len);
ring->element_len = (uint32_t)element_len;
ring->head = 0;
ring->oldest_tail = 0;
ring->destroy_element = destroy_element;
ring->buf = lws_malloc(ring->buflen, "ring buf");
if (!ring->buf) {
lws_free(ring);
return NULL;
}
return ring;
}