new att_server_delayed_read_response example

example/Makefile.inc

@@ -108,8 +108,9 @@ HXCMOD_PLAYER = \
 	${BTSTACK_ROOT}/3rd-party/hxcmod-player/mods/nao-deceased_by_disease.c 	\
 
 EXAMPLES = 					\
+	att_delayed_read_response \
 	a2dp_sink_demo			\
-	a2dp_source_demo       \
+	a2dp_source_demo        \
 	ancs_client_demo		\
 	dut_mode_classic        \
 	gap_dedicated_bonding	\
@@ -205,6 +206,9 @@ spp_counter: ${CORE_OBJ} ${COMMON_OBJ} ${CLASSIC_OBJ} spp_counter.c
 le_counter: le_counter.h ${CORE_OBJ} ${COMMON_OBJ} ${ATT_OBJ} ${GATT_SERVER_OBJ} ${SM_OBJ} battery_service_server.o le_counter.c
 	${CC} $(filter-out le_counter.h,$^) ${CFLAGS} ${LDFLAGS} -o $@
 
+att_delayed_read_response: att_delayed_read_response.h ${CORE_OBJ} ${COMMON_OBJ} ${ATT_OBJ} ${GATT_SERVER_OBJ} ${SM_OBJ} att_delayed_read_response.c
+	${CC} $(filter-out att_delayed_read_response.h,$^) ${CFLAGS} ${LDFLAGS} -o $@
+
 hog_keyboard_demo: hog_keyboard_demo.h ${CORE_OBJ} ${COMMON_OBJ} ${ATT_OBJ} ${GATT_SERVER_OBJ} ${SM_OBJ} battery_service_server.o device_information_service_server.o hids_device.o btstack_ring_buffer.o hog_keyboard_demo.c
 	${CC} $(filter-out hog_keyboard_demo.h,$^) ${CFLAGS} ${LDFLAGS} -o $@
 

example/att_delayed_read_response.c

@@ -0,0 +1,212 @@
+/*
+ * Copyright (C) 2018 BlueKitchen GmbH
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the copyright holders nor the names of
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ * 4. Any redistribution, use, or modification is done solely for
+ *    personal benefit and not for any commercial purpose or for
+ *    monetary gain.
+ *
+ * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
+ * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * Please inquire about commercial licensing options at 
+ * contact@bluekitchen-gmbh.com
+ *
+ */
+
+#define __BTSTACK_FILE__ "att_delayed_read_response.c"
+
+// *****************************************************************************
+/* EXAMPLE_START(att_delayed_read_response): LE Peripheral - Delayed Read Response
+ *
+ * @text If the value for a GATT Chararacteristic isn't available, the value
+ * ATT_READ_RESPONSE_PENDING can be returned. When the value is available, 
+ * att_server_read_response_ready is then called to complete the ATT request.
+ */
+ // *****************************************************************************
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "att_delayed_read_response.h"
+#include "btstack.h"
+
+#define ATT_VALUE_DELAY_MS   3000
+#define ATT_VALUE_INVALID_MS 5000
+
+/* @section Main Application Setup
+ *
+ * @text Listing MainConfiguration shows main application code.
+ * It initializes L2CAP, the Security Manager and configures the ATT Server with the pre-compiled
+ * ATT Database generated from $le_counter.gatt$. 
+ * Additionally, it enables the Battery Service Server with the current battery level.
+ * Finally, it configures the advertisements and boots the Bluetooth stack. 
+ * In this example, the Advertisement contains the Flags attribute and the device name.
+ * The flag 0x06 indicates: LE General Discoverable Mode and BR/EDR not supported.
+ */
+ 
+/* LISTING_START(MainConfiguration): Init L2CAP SM ATT Server */
+static btstack_timer_source_t att_timer;
+static hci_con_handle_t con_handle;
+static int value_ready;
+
+static uint16_t att_read_callback(hci_con_handle_t con_handle, uint16_t att_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size);
+
+const uint8_t adv_data[] = {
+    // Flags general discoverable, BR/EDR not supported
+    0x02, 0x01, 0x06, 
+    // Name
+    0x0b, 0x09, 'L', 'E', ' ', 'C', 'o', 'u', 'n', 't', 'e', 'r', 
+};
+const uint8_t adv_data_len = sizeof(adv_data);
+
+const char * test_string = "Delayed response";
+
+static void example_setup(void){
+
+    l2cap_init();
+
+    // setup le device db
+    le_device_db_init();
+
+    // setup SM: Display only
+    sm_init();
+
+    // setup ATT server
+    att_server_init(profile_data, att_read_callback, NULL);
+
+    // setup advertisements
+    uint16_t adv_int_min = 0x0030;
+    uint16_t adv_int_max = 0x0030;
+    uint8_t adv_type = 0;
+    bd_addr_t null_addr;
+    memset(null_addr, 0, 6);
+    gap_advertisements_set_params(adv_int_min, adv_int_max, adv_type, 0, null_addr, 0x07, 0x00);
+    gap_advertisements_set_data(adv_data_len, (uint8_t*) adv_data);
+    gap_advertisements_enable(1);
+}
+/* LISTING_END */
+
+/*
+ * @section att_invalidate_value Handler
+ *
+ * @text The att_invalidate_value handler 'invalidates' the value of the single Characteristic provided in this example
+ */
+
+static void att_invalidate_value(struct btstack_timer_source *ts){
+    UNUSED(ts);
+    printf("Value got stale\n");
+    value_ready = 0;
+} 
+
+/*
+ * @section att_update_value Handler
+ *
+ * @text The att_update_value handler 'updates' the value of the single Characteristic provided in this example
+ */
+
+ /* LISTING_START(att_read_delay): ATT Read Delay Handler */
+
+static void att_update_value(struct btstack_timer_source *ts){
+    UNUSED(ts);
+    value_ready = 1;
+
+
+    // trigger ATT Server to try request again
+    int status = att_server_read_response_ready(con_handle);
+
+    printf("Value updated -> complete ATT request - status %02x\n", status);
+
+    // simulated value becoming stale again
+    att_timer.process = &att_invalidate_value;
+    btstack_run_loop_set_timer(&att_timer, ATT_VALUE_DELAY_MS);
+    btstack_run_loop_add_timer(&att_timer);
+} 
+
+/* LISTING_END */
+
+/*
+ * @section ATT Read
+ *
+ * @text The ATT Server handles all reads to constant data. For dynamic data like the custom characteristic, the registered
+ * att_read_callback is called. To handle long characteristics and long reads, the att_read_callback is first called
+ * with buffer == NULL, to request the total value length. Then it will be called again requesting a chunk of the value.
+ * See Listing attRead.
+ */
+
+/* LISTING_START(attRead): ATT Read */
+
+// ATT Client Read Callback for Dynamic Data
+// - if buffer == NULL, don't copy data, just return size of value
+// - if buffer != NULL, copy data and return number bytes copied
+// @param offset defines start of attribute value
+static uint16_t att_read_callback(hci_con_handle_t connection_handle, uint16_t att_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size){
+
+#ifdef ENABLE_ATT_DELAYED_READ_RESPONSE
+    switch (att_handle){
+        case ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE:
+            if (value_ready){
+                return att_read_callback_handle_blob((const uint8_t *)test_string, strlen(test_string), offset, buffer, buffer_size);
+            } else {
+                printf("Read callback for handle %02x, but value not ready -> report response pending\n", att_handle);
+                con_handle = connection_handle;
+                return ATT_READ_RESPONSE_PENDING;
+            }
+            break;
+        case ATT_READ_RESPONSE_PENDING:
+            // virtual handle indicating all attributes have been queried
+            printf("Read callback for virtual handle %02x - all attributes have been queried (important for read multiple or read by type) -> start updating values\n", att_handle);
+            // simulated delayed response for example
+            att_timer.process = &att_update_value;
+            btstack_run_loop_set_timer(&att_timer, ATT_VALUE_DELAY_MS);
+            btstack_run_loop_add_timer(&att_timer);
+            return 0;
+        default:
+            break;
+    }
+#else
+    // useless code when ENABLE_ATT_DELAYED_READ_RESPONSE is not defined - but avoids built errors
+    if (att_handle == ATT_CHARACTERISTIC_0000FF11_0000_1000_8000_00805F9B34FB_01_VALUE_HANDLE){
+        printf("ENABLE_ATT_DELAYED_READ_RESPONSE not defined in btstack_config.h, responding right away");
+        return att_read_callback_handle_blob((const uint8_t *)test_string, strlen(test_string), offset, buffer, buffer_size);
+    }
+#endif
+
+    return 0;
+}
+/* LISTING_END */
+
+int btstack_main(void);
+int btstack_main(void)
+{
+    example_setup();
+
+    // turn on!
+	hci_power_control(HCI_POWER_ON);
+	    
+    return 0;
+}
+/* EXAMPLE_END */

example/att_delayed_read_response.gatt

@@ -0,0 +1,10 @@
+PRIMARY_SERVICE, GAP_SERVICE
+CHARACTERISTIC, GAP_DEVICE_NAME, READ, "LE Counter"
+
+PRIMARY_SERVICE, GATT_SERVICE
+CHARACTERISTIC, GATT_SERVICE_CHANGED, READ,
+
+// Counter Service
+PRIMARY_SERVICE, 0000FF10-0000-1000-8000-00805F9B34FB
+// Counter Characteristic, with read and notify
+CHARACTERISTIC,  0000FF11-0000-1000-8000-00805F9B34FB, READ | NOTIFY | DYNAMIC,

port/libusb/.gitignore

@@ -62,3 +62,5 @@ spp_counter
 spp_streamer
 spp_streamer_client
 spp_streamer_client
+att_delayed_read_response
+att_delayed_read_response.h

port/libusb/btstack_config.h

@@ -21,6 +21,7 @@
 #define ENABLE_LE_DATA_CHANNELS
 #define ENABLE_MICRO_ECC_FOR_LE_SECURE_CONNECTIONS
 #define ENABLE_LE_DATA_LENGTH_EXTENSION
+#define ENABLE_ATT_DELAYED_READ_RESPONSE
 #define ENABLE_LOG_ERROR
 #define ENABLE_LOG_INFO 
 #define ENABLE_SCO_OVER_HCI