/**
* Doesn't actually start the CM, just initializing. CM will run whenever
* an valid ssid is set through wl_cm_set_network() and wl_cm_start()
* has been called.
*/
wl_err_t
wl_cm_init(cm_scan_cb_t scan_cb,
cm_conn_cb_t conn_cb,
cm_disconn_cb_t disconn_cb,
void* ctx)
{
if (cm != NULL)
return WL_FAILURE;
cm = calloc(1, sizeof(struct cm));
if (cm == NULL) {
CM_DPRINTF("CM: out of memory\n");
return WL_FAILURE;
}
if (wl_register_event_cb(wl_event_cb, cm) != WL_SUCCESS) {
CM_DPRINTF("CM: could not register event cb\n");
return WL_FAILURE;
}
cm->scan_cb = scan_cb;
cm->conn_cb = conn_cb;
cm->disconn_cb = disconn_cb;
cm->enabled = 0;
cm->ctx = ctx;
CM_DPRINTF("CM: initialized\n");
return WL_SUCCESS;
}
static void
wl_event_cb(struct wl_event_t event, void* ctx)
{
struct cm *cm = ctx;
switch (event.id) {
case WL_EVENT_MEDIA_CONNECTED:
wl_media_connected_cb(cm);
break;
case WL_EVENT_CONN_FAILURE:
wl_conn_failure_cb(cm);
break;
case WL_EVENT_MEDIA_DISCONNECTED:
CM_DPRINTF("CM: disconnected\n");
wl_conn_lost_cb(cm);
break;
case WL_EVENT_SCAN_COMPLETE:
wl_scan_complete_cb(cm);
break;
default:
CM_DPRINTF("CM: unhandled event\n");
};
}
static void
wl_conn_failure_cb(void* ctx)
{
CM_DPRINTF("CM: connect failed, scanning\n");
if (wl_scan() != WL_SUCCESS)
/* should never happen */
CM_DPRINTF("CM: could not start scan after connect fail!\n");
}
static void
wl_conn_lost_cb(void* ctx)
{
struct cm *cm = ctx;
CM_DPRINTF("CM: connection lost, scanning\n");
if (cm->disconn_cb)
cm->disconn_cb(cm->ctx);
if (wl_scan() != WL_SUCCESS)
/* should never happen */
CM_DPRINTF("CM: could not start scan after connect lost!\n");
}
static void
wl_conn_failure_cb(void* ctx)
{
struct cm *cm = ctx;
CM_DPRINTF("CM: connect failed, scanning\n");
ERROR_LED_ON();
LINK_LED_OFF();
if ( 0 == cm->enabled ) {
return;
}
if (wl_scan() != WL_SUCCESS)
/* should never happen */
CM_DPRINTF("CM: could not start scan after connect fail!\n");
}
static void
wl_media_connected_cb(void* ctx)
{
struct cm *cm = ctx;
struct wl_network_t *net = wl_get_current_network();
CM_DPRINTF("CM: connected to %s\n", ssid2str(&net->ssid));
if (cm->conn_cb)
cm->conn_cb(net, cm->ctx);
}
static void
wl_scan_complete_cb(void* ctx)
{
struct cm *cm = ctx;
CM_DPRINTF("CM: scan completed\n");
if (cm->scan_cb)
cm->scan_cb(cm->ctx);
select_net(cm);
}
static void
select_net(struct cm* cm)
{
struct wl_network_t *candidate_net;
struct wl_network_t *current_net;
struct wl_ssid_t *ssid_p;
int ret;
/* Nothing to do */
if (0 == cm->candidate.ssid.len) {
return;
}
current_net = wl_get_current_network();
candidate_net = find_best_candidate(cm);
/* Connected to the candidate? ... */
if ( current_net == candidate_net ) {
if ( current_net ) {
/* ...yes, dont change. */
return;
}
}
/* Roaming checks */
if (current_net && candidate_net) {
/* Are we changing BSSs? */
if ( equal_ssid(&candidate_net->ssid,
¤t_net->ssid)) {
/* ...no. Does the currently connected
* net have a decent RSSI?...*/
if ( current_net->rssi > ROAMING_RSSI_THRESHOLD ) {
/* ...yes, stay with it. */
return;
}
/* ...no. Does the candidate have
* sufficiently better RSSI to
* motivate a switch to it? */
if ( candidate_net->rssi < current_net->rssi +
ROAMING_RSSI_DIFF) {
return;
}
/* ...yes, try to roam to candidate_net */
CM_DPRINTF("CM: Roaming from rssi %d to %d\n",
current_net->rssi,
candidate_net->rssi);
}
}
/* a candidate is found */
if (candidate_net) {
/* We connect to a specific bssid here because
* find_best_candidate() might have picked a
* particulare AP among many with the same SSID.
* wl_connect() would pick one of them at random.
*/
ret = wl_connect_bssid(candidate_net->bssid);
}
/* no candidate found */
else {
CM_DPRINTF("CM: No candidate found for ssid \"%s\"\n",
ssid2str(&cm->candidate.ssid));
/* Might be a hidden SSID so we try to connect to it.
* wl_connect() will trigger a directed scan
* for the SSID in this case.
*/
ssid_p = &cm->candidate.ssid;
ret = wl_connect(ssid_p->ssid, ssid_p->len);
}
switch (ret) {
case WL_SUCCESS :
return;
case WL_BUSY:
wl_disconnect();
return;
case WL_RETRY:
break;
default :
CM_DPRINTF("CM: failed to connect\n");
break;
}
/* some operation failed or no candidate found */
if (wl_scan() != WL_SUCCESS)
CM_DPRINTF("CM: failed to scan\n");
}
