android/gatt: Add client read descriptor handler

This patch adds descriptor reading. In case of providing wrong
descriptor, error status is being sent with notification.

diff --git a/android/gatt.c b/android/gatt.c
index 07fe161..c39bc32 100644 (file)
--- a/android/gatt.c
+++ b/android/gatt.c
@@ -48,6 +48,9 @@
 #include "attrib/gatt.h"
 #include "btio/btio.h"
 
+/* set according to Android bt_gatt_client.h */
+#define GATT_MAX_ATTR_LEN 600
+
 #define GATT_SUCCESS   0x00000000
 #define GATT_FAILURE   0x00000101
 
@@ -286,6 +289,17 @@ static bool match_char_by_higher_inst_id(const void *data,
        return inst_id < ch->id.instance;
 }
 
+static bool match_descr_by_element_id(const void *data, const void *user_data)
+{
+       const struct element_id *exp_id = user_data;
+       const struct descriptor *descr = data;
+
+       if (exp_id->instance == descr->id.instance)
+               return !bt_uuid_cmp(&descr->id.uuid, &exp_id->uuid);
+
+       return false;
+}
+
 static bool match_descr_by_higher_inst_id(const void *data,
                                                        const void *user_data)
 {
@@ -1877,12 +1891,147 @@ failed:
                                                cmd->srvc_id.is_primary);
 }
 
+static void send_client_descr_read_notify(int32_t status, const uint8_t *pdu,
+                                               guint16 len, int32_t conn_id,
+                                               const struct element_id *srvc,
+                                               const struct element_id *ch,
+                                               const struct element_id *descr,
+                                               uint8_t primary)
+{
+       uint8_t buf[IPC_MTU];
+       struct hal_ev_gatt_client_read_descriptor *ev = (void *) buf;
+
+       memset(buf, 0, sizeof(buf));
+
+       ev->status = status;
+       ev->conn_id = conn_id;
+
+       element_id_to_hal_srvc_id(srvc, primary, &ev->data.srvc_id);
+       element_id_to_hal_gatt_id(ch, &ev->data.char_id);
+       element_id_to_hal_gatt_id(descr, &ev->data.descr_id);
+
+       if (len && pdu) {
+               ssize_t ret;
+
+               ret = dec_read_resp(pdu, len, ev->data.value,
+                                                       GATT_MAX_ATTR_LEN);
+               if (ret < 0) {
+                       error("gatt: Protocol error");
+                       ev->status = GATT_FAILURE;
+               } else {
+                       ev->data.len = ret;
+               }
+       }
+
+       ipc_send_notif(hal_ipc, HAL_SERVICE_ID_GATT,
+                                       HAL_EV_GATT_CLIENT_READ_DESCRIPTOR,
+                                       sizeof(*ev) + ev->data.len, ev);
+}
+
+struct desc_data {
+       int32_t conn_id;
+       const struct element_id *srvc_id;
+       const struct element_id *char_id;
+       const struct element_id *descr_id;
+       uint8_t primary;
+};
+
+static void read_desc_cb(guint8 status, const guint8 *pdu, guint16 len,
+                                                       gpointer user_data)
+{
+       struct desc_data *cb_data = user_data;
+
+       if (status != 0)
+               error("gatt: Discover all char descriptors failed: %s",
+                                                       att_ecode2str(status));
+
+       send_client_descr_read_notify(status, pdu, len, cb_data->conn_id,
+                                       cb_data->srvc_id, cb_data->char_id,
+                                       cb_data->descr_id, cb_data->primary);
+
+       free(cb_data);
+}
+
 static void handle_client_read_descriptor(const void *buf, uint16_t len)
 {
+       const struct hal_cmd_gatt_client_read_descriptor *cmd = buf;
+       struct desc_data *cb_data;
+       struct characteristic *ch;
+       struct descriptor *descr;
+       struct service *srvc;
+       struct element_id char_id;
+       struct element_id descr_id;
+       struct element_id srvc_id;
+       struct gatt_device *dev;
+       int32_t conn_id = 0;
+       uint8_t primary;
+       uint8_t status;
+
        DBG("");
 
+       conn_id = cmd->conn_id;
+       primary = cmd->srvc_id.is_primary;
+
+       hal_srvc_id_to_element_id(&cmd->srvc_id, &srvc_id);
+       hal_gatt_id_to_element_id(&cmd->char_id, &char_id);
+       hal_gatt_id_to_element_id(&cmd->descr_id, &descr_id);
+
+       if (!find_service(conn_id, &srvc_id, &dev, &srvc)) {
+               error("gatt: Read descr. could not find service");
+
+               status = HAL_STATUS_FAILED;
+               goto failed;
+       }
+
+       ch = queue_find(srvc->chars, match_char_by_element_id, &char_id);
+       if (!ch) {
+               error("gatt: Read descr. could not find characteristic");
+
+               status = HAL_STATUS_FAILED;
+               goto failed;
+       }
+
+       descr = queue_find(ch->descriptors, match_descr_by_element_id,
+                                                               &descr_id);
+       if (!descr) {
+               error("gatt: Read descr. could not find descriptor");
+
+               status = HAL_STATUS_FAILED;
+               goto failed;
+       }
+
+       cb_data = new0(struct desc_data, 1);
+       if (!cb_data) {
+               error("gatt: Read descr. could not allocate callback data");
+
+               status = HAL_STATUS_NOMEM;
+               goto failed;
+       }
+
+       cb_data->conn_id = conn_id;
+       cb_data->srvc_id = &srvc->id;
+       cb_data->char_id = &ch->id;
+       cb_data->descr_id = &descr->id;
+       cb_data->primary = primary;
+
+       if (!gatt_read_char(dev->attrib, descr->handle, read_desc_cb,
+                                                               cb_data)) {
+               free(cb_data);
+
+               status = HAL_STATUS_FAILED;
+               goto failed;
+       }
+
+       status = HAL_STATUS_SUCCESS;
+
+failed:
+       if (status != HAL_STATUS_SUCCESS)
+               send_client_descr_read_notify(GATT_FAILURE, NULL, 0, conn_id,
+                                               &srvc_id, &char_id, &descr_id,
+                                               primary);
+
        ipc_send_rsp(hal_ipc, HAL_SERVICE_ID_GATT,
-                       HAL_OP_GATT_CLIENT_READ_DESCRIPTOR, HAL_STATUS_FAILED);
+                       HAL_OP_GATT_CLIENT_READ_DESCRIPTOR, status);
 }
 
 static void handle_client_write_descriptor(const void *buf, uint16_t len)