1 /* main.c - Host long advertising receive */
2 
3 /*
4  * Copyright (c) 2021-2024 Nordic Semiconductor ASA
5  *
6  * SPDX-License-Identifier: Apache-2.0
7  */
8 
9 #include <stddef.h>
10 
11 #include <zephyr/bluetooth/hci_types.h>
12 #include <zephyr/fff.h>
13 #include <zephyr/kernel.h>
14 #include <zephyr/ztest.h>
15 
16 #include <errno.h>
17 #include <zephyr/tc_util.h>
18 
19 #include <zephyr/bluetooth/hci.h>
20 #include <zephyr/bluetooth/buf.h>
21 #include <zephyr/bluetooth/bluetooth.h>
22 #include <zephyr/drivers/bluetooth.h>
23 #include <zephyr/sys/byteorder.h>
24 #include <zephyr/ztest_assert.h>
25 
26 #define DT_DRV_COMPAT zephyr_bt_hci_test
27 
28 struct driver_data {
29 	bt_hci_recv_t recv;
30 };
31 
32 #define LOG_LEVEL CONFIG_BT_LOG_LEVEL
33 #include <zephyr/logging/log.h>
34 LOG_MODULE_REGISTER(host_test_app);
35 
36 DEFINE_FFF_GLOBALS;
37 
38 struct test_adv_report {
39 	uint8_t data[CONFIG_BT_EXT_SCAN_BUF_SIZE];
40 	uint8_t length;
41 	uint16_t evt_prop;
42 	bt_addr_le_t addr;
43 };
44 
45 #define COMPLETE BT_HCI_LE_ADV_EVT_TYPE_DATA_STATUS_COMPLETE << 5
46 #define MORE_TO_COME BT_HCI_LE_ADV_EVT_TYPE_DATA_STATUS_PARTIAL << 5
47 #define TRUNCATED BT_HCI_LE_ADV_EVT_TYPE_DATA_STATUS_INCOMPLETE << 5
48 
49 /* Command handler structure for cmd_handle(). */
50 struct cmd_handler {
51 	uint16_t opcode; /* HCI command opcode */
52 	uint8_t len; /* HCI command response length */
53 	void (*handler)(struct net_buf *buf, struct net_buf **evt, uint8_t len, uint16_t opcode);
54 };
55 
56 /* Add event to net_buf. */
evt_create(struct net_buf * buf,uint8_t evt,uint8_t len)57 static void evt_create(struct net_buf *buf, uint8_t evt, uint8_t len)
58 {
59 	struct bt_hci_evt_hdr *hdr;
60 
61 	hdr = net_buf_add(buf, sizeof(*hdr));
62 	hdr->evt = evt;
63 	hdr->len = len;
64 }
65 
le_meta_evt_create(struct bt_hci_evt_le_meta_event * evt,uint8_t subevent)66 static void le_meta_evt_create(struct bt_hci_evt_le_meta_event *evt, uint8_t subevent)
67 {
68 	evt->subevent = subevent;
69 }
70 
adv_info_create(struct bt_hci_evt_le_ext_advertising_info * evt,uint16_t evt_type,const bt_addr_le_t * const addr,uint8_t length)71 static void adv_info_create(struct bt_hci_evt_le_ext_advertising_info *evt, uint16_t evt_type,
72 			    const bt_addr_le_t *const addr, uint8_t length)
73 {
74 	evt->evt_type = evt_type;
75 	bt_addr_le_copy(&evt->addr, addr);
76 	evt->prim_phy = 0;
77 	evt->sec_phy = 0;
78 	evt->sid = 0;
79 	evt->tx_power = 0;
80 	evt->rssi = 0;
81 	evt->interval = 0;
82 	bt_addr_le_copy(&evt->direct_addr, BT_ADDR_LE_NONE);
83 	evt->length = length;
84 }
85 
86 /* Create a command complete event. */
cmd_complete(struct net_buf ** buf,uint8_t plen,uint16_t opcode)87 static void *cmd_complete(struct net_buf **buf, uint8_t plen, uint16_t opcode)
88 {
89 	struct bt_hci_evt_cmd_complete *cc;
90 
91 	*buf = bt_buf_get_evt(BT_HCI_EVT_CMD_COMPLETE, false, K_FOREVER);
92 	evt_create(*buf, BT_HCI_EVT_CMD_COMPLETE, sizeof(*cc) + plen);
93 	cc = net_buf_add(*buf, sizeof(*cc));
94 	cc->ncmd = 1U;
95 	cc->opcode = sys_cpu_to_le16(opcode);
96 
97 	return net_buf_add(*buf, plen);
98 }
99 
100 /* Loop over handlers to try to handle the command given by opcode. */
cmd_handle_helper(uint16_t opcode,struct net_buf * cmd,struct net_buf ** evt,const struct cmd_handler * handlers,size_t num_handlers)101 static int cmd_handle_helper(uint16_t opcode, struct net_buf *cmd, struct net_buf **evt,
102 			     const struct cmd_handler *handlers, size_t num_handlers)
103 {
104 	for (size_t i = 0; i < num_handlers; i++) {
105 		const struct cmd_handler *handler = &handlers[i];
106 
107 		if (handler->opcode != opcode) {
108 			continue;
109 		}
110 
111 		if (handler->handler) {
112 			handler->handler(cmd, evt, handler->len, opcode);
113 
114 			return 0;
115 		}
116 	}
117 
118 	zassert_unreachable("opcode %X failed", opcode);
119 
120 	return -EINVAL;
121 }
122 
123 /* Lookup the command opcode and invoke handler. */
cmd_handle(const struct device * dev,struct net_buf * cmd,const struct cmd_handler * handlers,size_t num_handlers)124 static int cmd_handle(const struct device *dev, struct net_buf *cmd,
125 		      const struct cmd_handler *handlers, size_t num_handlers)
126 {
127 	struct driver_data *drv = dev->data;
128 	struct net_buf *evt = NULL;
129 	struct bt_hci_evt_cc_status *ccst;
130 	struct bt_hci_cmd_hdr *chdr;
131 	uint16_t opcode;
132 	int err;
133 
134 	chdr = net_buf_pull_mem(cmd, sizeof(*chdr));
135 	opcode = sys_le16_to_cpu(chdr->opcode);
136 
137 	err = cmd_handle_helper(opcode, cmd, &evt, handlers, num_handlers);
138 
139 	if (err == -EINVAL) {
140 		ccst = cmd_complete(&evt, sizeof(*ccst), opcode);
141 		ccst->status = BT_HCI_ERR_UNKNOWN_CMD;
142 	}
143 
144 	if (evt) {
145 		drv->recv(dev, evt);
146 	}
147 
148 	return err;
149 }
150 
151 /* Generic command complete with success status. */
generic_success(struct net_buf * buf,struct net_buf ** evt,uint8_t len,uint16_t opcode)152 static void generic_success(struct net_buf *buf, struct net_buf **evt, uint8_t len, uint16_t opcode)
153 {
154 	struct bt_hci_evt_cc_status *ccst;
155 
156 	ccst = cmd_complete(evt, len, opcode);
157 
158 	/* Fill any event parameters with zero */
159 	(void)memset(ccst, 0, len);
160 
161 	ccst->status = BT_HCI_ERR_SUCCESS;
162 }
163 
164 /* Bogus handler for BT_HCI_OP_READ_LOCAL_FEATURES. */
read_local_features(struct net_buf * buf,struct net_buf ** evt,uint8_t len,uint16_t opcode)165 static void read_local_features(struct net_buf *buf, struct net_buf **evt, uint8_t len,
166 				uint16_t opcode)
167 {
168 	struct bt_hci_rp_read_local_features *rp;
169 
170 	rp = cmd_complete(evt, sizeof(*rp), opcode);
171 	rp->status = 0x00;
172 	(void)memset(rp->features, 0xFF, sizeof(rp->features));
173 }
174 
175 /* Bogus handler for BT_HCI_OP_READ_SUPPORTED_COMMANDS. */
read_supported_commands(struct net_buf * buf,struct net_buf ** evt,uint8_t len,uint16_t opcode)176 static void read_supported_commands(struct net_buf *buf, struct net_buf **evt, uint8_t len,
177 				    uint16_t opcode)
178 {
179 	struct bt_hci_rp_read_supported_commands *rp;
180 
181 	rp = cmd_complete(evt, sizeof(*rp), opcode);
182 	(void)memset(rp->commands, 0xFF, sizeof(rp->commands));
183 	rp->status = 0x00;
184 }
185 
186 /* Bogus handler for BT_HCI_OP_LE_READ_LOCAL_FEATURES. */
le_read_local_features(struct net_buf * buf,struct net_buf ** evt,uint8_t len,uint16_t opcode)187 static void le_read_local_features(struct net_buf *buf, struct net_buf **evt, uint8_t len,
188 				   uint16_t opcode)
189 {
190 	struct bt_hci_rp_le_read_local_features *rp;
191 
192 	rp = cmd_complete(evt, sizeof(*rp), opcode);
193 	rp->status = 0x00;
194 	(void)memset(rp->features, 0xFF, sizeof(rp->features));
195 }
196 
197 /* Bogus handler for BT_HCI_OP_LE_READ_SUPP_STATES. */
le_read_supp_states(struct net_buf * buf,struct net_buf ** evt,uint8_t len,uint16_t opcode)198 static void le_read_supp_states(struct net_buf *buf, struct net_buf **evt, uint8_t len,
199 				uint16_t opcode)
200 {
201 	struct bt_hci_rp_le_read_supp_states *rp;
202 
203 	rp = cmd_complete(evt, sizeof(*rp), opcode);
204 	rp->status = 0x00;
205 	(void)memset(&rp->le_states, 0xFF, sizeof(rp->le_states));
206 }
207 
208 
209 /* Setup handlers needed for bt_enable to function. */
210 static const struct cmd_handler cmds[] = {
211 	{ BT_HCI_OP_READ_LOCAL_VERSION_INFO, sizeof(struct bt_hci_rp_read_local_version_info),
212 	  generic_success },
213 	{ BT_HCI_OP_READ_SUPPORTED_COMMANDS, sizeof(struct bt_hci_rp_read_supported_commands),
214 	  read_supported_commands },
215 	{ BT_HCI_OP_READ_LOCAL_FEATURES, sizeof(struct bt_hci_rp_read_local_features),
216 	  read_local_features },
217 	{ BT_HCI_OP_READ_BD_ADDR, sizeof(struct bt_hci_rp_read_bd_addr), generic_success },
218 	{ BT_HCI_OP_SET_EVENT_MASK, sizeof(struct bt_hci_evt_cc_status), generic_success },
219 	{ BT_HCI_OP_LE_SET_EVENT_MASK, sizeof(struct bt_hci_evt_cc_status), generic_success },
220 	{ BT_HCI_OP_LE_READ_LOCAL_FEATURES, sizeof(struct bt_hci_rp_le_read_local_features),
221 	  le_read_local_features },
222 	{ BT_HCI_OP_LE_READ_SUPP_STATES, sizeof(struct bt_hci_rp_le_read_supp_states),
223 	  le_read_supp_states },
224 	{ BT_HCI_OP_LE_RAND, sizeof(struct bt_hci_rp_le_rand), generic_success },
225 	{ BT_HCI_OP_LE_SET_RANDOM_ADDRESS, sizeof(struct bt_hci_cp_le_set_random_address),
226 	  generic_success },
227 	{ BT_HCI_OP_LE_SET_EXT_SCAN_PARAM, 0, generic_success },
228 	{ BT_HCI_OP_LE_SET_EXT_SCAN_ENABLE, 0, generic_success },
229 	{ BT_HCI_OP_RESET, 0, generic_success },
230 };
231 
232 /* HCI driver open. */
driver_open(const struct device * dev,bt_hci_recv_t recv)233 static int driver_open(const struct device *dev, bt_hci_recv_t recv)
234 {
235 	struct driver_data *drv = dev->data;
236 
237 	drv->recv = recv;
238 
239 	return 0;
240 }
241 
242 /*  HCI driver send.  */
driver_send(const struct device * dev,struct net_buf * buf)243 static int driver_send(const struct device *dev, struct net_buf *buf)
244 {
245 	zassert_true(cmd_handle(dev, buf, cmds, ARRAY_SIZE(cmds)) == 0, "Unknown HCI command");
246 
247 	net_buf_unref(buf);
248 
249 	return 0;
250 }
251 
252 static DEVICE_API(bt_hci, driver_api) = {
253 	.open = driver_open,
254 	.send = driver_send,
255 };
256 
257 #define TEST_DEVICE_INIT(inst) \
258 	static struct driver_data driver_data_##inst = { \
259 	}; \
260 	DEVICE_DT_INST_DEFINE(inst, NULL, NULL, &driver_data_##inst, NULL, \
261 			      POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &driver_api)
262 
263 DT_INST_FOREACH_STATUS_OKAY(TEST_DEVICE_INIT)
264 
265 
266 struct bt_recv_job_data {
267 	struct k_work work; /* Work item */
268 	struct k_sem *sync; /* Semaphore to synchronize with */
269 	struct net_buf *buf; /* Net buffer to be passed to bt_recv() */
270 } job_data[CONFIG_BT_BUF_EVT_RX_COUNT];
271 
272 #define job(buf) (&job_data[net_buf_id(buf)])
273 
274 /* Work item handler for bt_recv() jobs. */
bt_recv_job_cb(struct k_work * item)275 static void bt_recv_job_cb(struct k_work *item)
276 {
277 	const struct device *dev = DEVICE_DT_GET(DT_DRV_INST(0));
278 	struct driver_data *drv = dev->data;
279 	struct bt_recv_job_data *data = CONTAINER_OF(item, struct bt_recv_job_data, work);
280 
281 	/* Send net buffer to host */
282 	drv->recv(dev, data->buf);
283 
284 	/* Wake up bt_recv_job_submit */
285 	k_sem_give(job(data->buf)->sync);
286 }
287 
288 /* Prepare a job to call bt_recv() to be submitted to the system workqueue. */
bt_recv_job_submit(struct net_buf * buf)289 static void bt_recv_job_submit(struct net_buf *buf)
290 {
291 	struct k_sem sync_sem;
292 
293 	/* Store the net buffer to be passed to bt_recv */
294 	job(buf)->buf = buf;
295 
296 	/* Initialize job work item/semaphore */
297 	k_work_init(&job(buf)->work, bt_recv_job_cb);
298 	k_sem_init(&sync_sem, 0, 1);
299 	job(buf)->sync = &sync_sem;
300 
301 	/* Make sure the buffer stays around until the command completes */
302 	buf = net_buf_ref(buf);
303 
304 	/* Submit the work item */
305 	k_work_submit(&job(buf)->work);
306 
307 	/* Wait for bt_recv_job_cb to be done */
308 	k_sem_take(&sync_sem, K_FOREVER);
309 
310 	net_buf_unref(buf);
311 }
312 
313 /* Semaphore to test if the prop callback was called. */
314 static K_SEM_DEFINE(prop_cb_sem, 0, 1);
315 
adv_report_evt(struct net_buf * buf,uint8_t data_len,uint16_t evt_type,const bt_addr_le_t * const addr)316 static void *adv_report_evt(struct net_buf *buf, uint8_t data_len, uint16_t evt_type,
317 			    const bt_addr_le_t *const addr)
318 {
319 	struct bt_hci_evt_le_meta_event *meta_evt;
320 	struct bt_hci_evt_le_ext_advertising_info *evt;
321 
322 	evt_create(buf, BT_HCI_EVT_LE_META_EVENT, sizeof(*meta_evt) + sizeof(*evt) + data_len + 1);
323 	meta_evt = net_buf_add(buf, sizeof(*meta_evt));
324 	le_meta_evt_create(meta_evt, BT_HCI_EVT_LE_EXT_ADVERTISING_REPORT);
325 	net_buf_add_u8(buf, 1); /* Number of reports */
326 	evt = net_buf_add(buf, sizeof(*evt));
327 	adv_info_create(evt, evt_type, addr, data_len);
328 
329 	return net_buf_add(buf, data_len);
330 }
331 
332 /* Send a prop event report wit the given data. */
send_adv_report(const struct test_adv_report * report)333 static void send_adv_report(const struct test_adv_report *report)
334 {
335 	LOG_DBG("Sending adv report");
336 	struct net_buf *buf;
337 	uint8_t *adv_data;
338 
339 	buf = bt_buf_get_rx(BT_BUF_EVT, K_FOREVER);
340 	adv_data = adv_report_evt(buf, report->length, report->evt_prop, &report->addr);
341 	memcpy(adv_data, &report->data, report->length);
342 
343 	/* Submit job */
344 	bt_recv_job_submit(buf);
345 }
346 
347 FAKE_VALUE_FUNC(struct test_adv_report, get_expected_report);
348 
scan_recv_cb(const struct bt_le_scan_recv_info * info,struct net_buf_simple * buf)349 static void scan_recv_cb(const struct bt_le_scan_recv_info *info, struct net_buf_simple *buf)
350 {
351 	ARG_UNUSED(info);
352 
353 	LOG_DBG("Received event with length %u", buf->len);
354 
355 	const struct test_adv_report expected = get_expected_report();
356 
357 	zassert_equal(buf->len, expected.length, "Lengths should be equal");
358 	zassert_mem_equal(buf->data, expected.data, buf->len, "Data should be equal");
359 }
360 
scan_timeout_cb(void)361 static void scan_timeout_cb(void)
362 {
363 	zassert_unreachable("Timeout should not happen");
364 }
365 
generate_sequence(uint8_t * dest,uint16_t len,uint8_t range_start,uint8_t range_end)366 static void generate_sequence(uint8_t *dest, uint16_t len, uint8_t range_start, uint8_t range_end)
367 {
368 	uint16_t written = 0;
369 	uint8_t value = range_start;
370 
371 	while (written < len) {
372 		*dest++ = value++;
373 		written++;
374 		if (value > range_end) {
375 			value = range_start;
376 		}
377 	}
378 }
379 
380 ZTEST_SUITE(long_adv_rx_tests, NULL, NULL, NULL, NULL, NULL);
381 
ZTEST(long_adv_rx_tests,test_host_long_adv_recv)382 ZTEST(long_adv_rx_tests, test_host_long_adv_recv)
383 {
384 	struct test_adv_report expected_reports[2];
385 
386 	/* Go! Wait until Bluetooth initialization is done  */
387 	zassert_true((bt_enable(NULL) == 0), "bt_enable failed");
388 
389 	static struct bt_le_scan_cb scan_callbacks = { .recv = scan_recv_cb,
390 						       .timeout = scan_timeout_cb };
391 	bt_le_scan_cb_register(&scan_callbacks);
392 	zassert_true((bt_le_scan_start(BT_LE_SCAN_PASSIVE, NULL) == 0), "bt_le_scan_start failed");
393 
394 	bt_addr_le_t addr_a;
395 	bt_addr_le_t addr_b;
396 	bt_addr_le_t addr_c;
397 	bt_addr_le_t addr_d;
398 
399 	bt_addr_le_create_static(&addr_a);
400 	bt_addr_le_create_static(&addr_b);
401 	bt_addr_le_create_static(&addr_c);
402 	bt_addr_le_create_static(&addr_d);
403 
404 	struct test_adv_report report_a_1 = { .length = 30, .evt_prop = MORE_TO_COME };
405 	struct test_adv_report report_a_2 = { .length = 30, .evt_prop = COMPLETE };
406 
407 	bt_addr_le_copy(&report_a_1.addr, &addr_a);
408 	bt_addr_le_copy(&report_a_2.addr, &addr_a);
409 
410 	struct test_adv_report report_b_1 = { .length = 30, .evt_prop = MORE_TO_COME };
411 	struct test_adv_report report_b_2 = { .length = 30, .evt_prop = COMPLETE };
412 
413 	bt_addr_le_copy(&report_b_1.addr, &addr_b);
414 	bt_addr_le_copy(&report_b_2.addr, &addr_b);
415 
416 	struct test_adv_report report_c = { .length = 30,
417 					    .evt_prop = COMPLETE | BT_HCI_LE_ADV_EVT_TYPE_LEGACY };
418 
419 	bt_addr_le_copy(&report_c.addr, &addr_c);
420 
421 	struct test_adv_report report_d = { .length = 30, .evt_prop = TRUNCATED };
422 
423 	bt_addr_le_copy(&report_c.addr, &addr_c);
424 
425 	struct test_adv_report report_a_combined = { .length = report_a_1.length +
426 							       report_a_2.length };
427 
428 	struct test_adv_report report_a_1_repeated = { .length = CONFIG_BT_EXT_SCAN_BUF_SIZE };
429 
430 	struct test_adv_report report_b_combined = { .length = report_b_1.length +
431 							       report_b_2.length };
432 
433 	generate_sequence(report_a_combined.data, report_a_combined.length, 'A', 'Z');
434 	generate_sequence(report_b_combined.data, report_b_combined.length, 'a', 'z');
435 	generate_sequence(report_c.data, report_c.length, '0', '9');
436 
437 	(void)memcpy(report_a_1.data, report_a_combined.data, report_a_1.length);
438 	(void)memcpy(report_a_2.data, &report_a_combined.data[report_a_1.length],
439 		     report_a_2.length);
440 
441 	for (int i = 0; i < report_a_1_repeated.length; i += report_a_1.length) {
442 		memcpy(&report_a_1_repeated.data[i], report_a_1.data,
443 		       MIN(report_a_1.length, (report_a_1_repeated.length - i)));
444 	}
445 
446 	(void)memcpy(report_b_1.data, report_b_combined.data, report_b_1.length);
447 	(void)memcpy(report_b_2.data, &report_b_combined.data[report_b_1.length],
448 		     report_b_2.length);
449 
450 	/* Check that non-interleaved fragmented adv reports work */
451 	expected_reports[0] = report_a_combined;
452 	expected_reports[1] = report_b_combined;
453 	SET_RETURN_SEQ(get_expected_report, expected_reports, 2);
454 	send_adv_report(&report_a_1);
455 	send_adv_report(&report_a_2);
456 	send_adv_report(&report_b_1);
457 	send_adv_report(&report_b_2);
458 	zassert_equal(2, get_expected_report_fake.call_count);
459 	RESET_FAKE(get_expected_report);
460 	FFF_RESET_HISTORY();
461 
462 	/* Check that legacy adv reports interleaved with fragmented adv reports work */
463 	expected_reports[0] = report_c;
464 	expected_reports[1] = report_a_combined;
465 	SET_RETURN_SEQ(get_expected_report, expected_reports, 2);
466 	send_adv_report(&report_a_1);
467 	send_adv_report(&report_c); /* Interleaved legacy adv report */
468 	send_adv_report(&report_a_2);
469 	zassert_equal(2, get_expected_report_fake.call_count);
470 	RESET_FAKE(get_expected_report);
471 	FFF_RESET_HISTORY();
472 
473 	/* Check that complete adv reports interleaved with fragmented adv reports work */
474 	expected_reports[0] = report_b_2;
475 	expected_reports[1] = report_a_combined;
476 	SET_RETURN_SEQ(get_expected_report, expected_reports, 2);
477 	send_adv_report(&report_a_1);
478 	send_adv_report(&report_b_2); /* Interleaved short extended adv report */
479 	send_adv_report(&report_a_2);
480 	zassert_equal(2, get_expected_report_fake.call_count);
481 	RESET_FAKE(get_expected_report);
482 	FFF_RESET_HISTORY();
483 
484 	/* Check that fragmented adv reports from one peer are received,
485 	 * and that interleaved fragmented adv reports from other peers are discarded
486 	 */
487 	expected_reports[0] = report_a_combined;
488 	expected_reports[1] = report_b_2;
489 	SET_RETURN_SEQ(get_expected_report, expected_reports, 2);
490 	send_adv_report(&report_a_1);
491 	send_adv_report(&report_b_1); /* Interleaved fragmented adv report, NOT SUPPORTED */
492 	send_adv_report(&report_a_2);
493 	send_adv_report(&report_b_2);
494 	zassert_equal(2, get_expected_report_fake.call_count);
495 	RESET_FAKE(get_expected_report);
496 	FFF_RESET_HISTORY();
497 
498 	/* Check that host discards the data if the controller keeps sending
499 	 * incomplete packets.
500 	 */
501 	expected_reports[0] = report_b_combined;
502 	SET_RETURN_SEQ(get_expected_report, expected_reports, 1);
503 	for (int i = 0; i < (2 + (CONFIG_BT_EXT_SCAN_BUF_SIZE / report_a_1.length)); i++) {
504 		send_adv_report(&report_a_1);
505 	}
506 	send_adv_report(&report_a_2);
507 
508 	/* Check that controller truncated reports do not generate events */
509 	send_adv_report(&report_d);
510 
511 	/* Check that reports from a different advertiser works after truncation */
512 	send_adv_report(&report_b_1);
513 	send_adv_report(&report_b_2);
514 	zassert_equal(1, get_expected_report_fake.call_count);
515 }
516