lib: Create API to start and stop BLE scanning

2 files changed, 75 insertions, 1 deletions

diff --git a/lib/ble.c b/lib/ble.c
index a58b0a5..960b046 100644
--- a/lib/ble.c
+++ b/lib/ble.c
@@ -41,8 +41,47 @@ static struct libdata {
     int client;
 
     uint8_t adapter_state;
+    uint8_t scan_state;
 } data;
 
+/* Called every time an advertising report is seen */
+static void scan_result_cb(bt_bdaddr_t *bda, int rssi, uint8_t *adv_data) {
+    if (data.cbs.scan_cb)
+        data.cbs.scan_cb(bda->address, rssi, adv_data);
+}
+
+static int ble_scan(uint8_t start) {
+    bt_status_t s;
+
+    if (!data.client)
+        return -1;
+
+    if (data.gattiface == NULL)
+        return -1;
+
+    if (!data.adapter_state)
+        return -1;
+
+    if (data.scan_state == start)
+        return 1;
+
+    s = data.gattiface->client->scan(data.client, start);
+    if (s != BT_STATUS_SUCCESS)
+        return -s;
+
+    data.scan_state = start;
+
+    return 0;
+}
+
+int ble_start_scan() {
+    return ble_scan(1);
+}
+
+int ble_stop_scan() {
+    return ble_scan(0);
+}
+
 /* Called when the client registration is finished */
 static void register_client_cb(int status, int client_if, bt_uuid_t *app_uuid) {
     if (status == BT_STATUS_SUCCESS) {
@@ -56,7 +95,7 @@ static void register_client_cb(int status, int client_if, bt_uuid_t *app_uuid) {
 /* GATT client interface callbacks */
 static const btgatt_client_callbacks_t gattccbs = {
     register_client_cb,
-    NULL, /* scan_result_cb */
+    scan_result_cb,
     NULL, /* connect_cb */
     NULL, /* disconnect_cb */
     NULL, /* search_complete_cb */
diff --git a/lib/ble.h b/lib/ble.h
index c4e4edd..481e076 100644
--- a/lib/ble.h
+++ b/lib/ble.h
@@ -55,11 +55,26 @@ typedef void (*ble_enable_cb_t)(void);
 typedef void (*ble_adapter_state_cb_t)(uint8_t state);
 
 /**
+ * Type that represents a callback function to notify of a new found device
+ * during a scanning session.
+ *
+ * @param address A pointer to a 6 element array representing each part of the
+ *                Bluetooth address of the found device, where the
+ *                most-significant byte is on position 0 and the
+ *                least-sifnificant byte is on position 5.
+ * @param rssi The RSSI of the found device.
+ * @param adv_data A pointer to the advertising data of the found device.
+ */
+typedef void (*ble_scan_cb_t)(const uint8_t *address, int rssi,
+                              const uint8_t *adv_data);
+
+/**
  * List of callbacks for BLE operations.
  */
 typedef struct ble_cbs {
     ble_enable_cb_t enable_cb;
     ble_adapter_state_cb_t adapter_state_cb;
+    ble_scan_cb_t scan_cb;
 } ble_cbs_t;
 
 /**
@@ -79,4 +94,24 @@ int ble_enable(ble_cbs_t cbs);
  * @return Negative value on failure.
  */
 int ble_disable();
+
+/**
+ * Starts a LE scan procedure on the adapter.
+ *
+ * Scan will run indefinitelly until ble_scan_stop() is called.
+ *
+ * @return 0 if scan has been started.
+ * @return 1 if adapter is already scanning.
+ * @return -1 if failed to request scan start.
+ */
+int ble_start_scan();
+
+/**
+ * Stops a running LE scan procedure on the adapter.
+ *
+ * @return 0 if scan has been stopped.
+ * @return 1 if adapter is not scanning.
+ * @return -1 if failed to request scan stop.
+ */
+int ble_stop_scan();
 #endif