2 * This file is part of the sigrok project.
4 * Copyright (C) 2018-2019 Gerhard Sittig <gerhard.sittig@gmx.net>
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
21 * Scan support for Bluetooth LE devices is modelled after the MIT licensed
22 * https://github.com/carsonmcdonald/bluez-experiments experiments/scantest.c
23 * example source code which is:
25 * The MIT License (MIT)
27 * Copyright (c) 2013 Carson McDonald
29 * Permission is hereby granted, free of charge, to any person obtaining a copy of
30 * this software and associated documentation files (the "Software"), to deal in
31 * the Software without restriction, including without limitation the rights to
32 * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
33 * the Software, and to permit persons to whom the Software is furnished to do so,
34 * subject to the following conditions:
36 * The above copyright notice and this permission notice shall be included in all
37 * copies or substantial portions of the Software.
39 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
40 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
41 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
42 * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
43 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
44 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
48 * This file implements an internal platform agnostic API of libsigrok
49 * for Bluetooth communication, as well as the first implementation on a
50 * specific platform which is based on the BlueZ library and got tested
54 * - Separate the "common" from the "bluez specific" parts. The current
55 * implementation uses the fact that HAVE_BLUETOOTH exclusively depends
56 * on HAVE_LIBBLUEZ, and thus both are identical.
57 * - Add missing features to the Linux platform support: Scan without
58 * root privileges, UUID to handle translation.
59 * - Add support for other platforms.
64 /* Unconditionally compile the source, optionally end up empty. */
68 #include <bluetooth/bluetooth.h>
69 #include <bluetooth/hci.h>
70 #include <bluetooth/hci_lib.h>
71 #include <bluetooth/l2cap.h>
72 #include <bluetooth/rfcomm.h>
83 #include <sys/socket.h>
87 #include <libsigrok/libsigrok.h>
88 #include "libsigrok-internal.h"
91 #define LOG_PREFIX "bt-bluez"
94 #define CONNECT_BLE_TIMEOUT 20 /* Connect timeout in seconds. */
95 #define STORE_MAC_REVERSE 1
96 #define ACCEPT_NONSEP_MAC 1
98 /* Silence warning about (currently) unused routine. */
99 #define WITH_WRITE_TYPE_HANDLE 0
101 /* {{{ compat decls */
103 * The availability of conversion helpers in <bluetooth/bluetooth.h>
104 * appears to be version dependent. Let's provide the helper here if
105 * the header doesn't.
108 #if !defined HAVE_BT_PUT_LE16
109 static inline void bt_put_le16(uint16_t v, uint8_t *p)
111 p[0] = (v >> 0) & 0xff;
112 p[1] = (v >> 8) & 0xff;
116 /* }}} compat decls */
117 /* {{{ Linux socket specific decls */
119 #define BLE_ATT_ERROR_RESP 0x01
120 #define BLE_ATT_EXCHANGE_MTU_REQ 0x02
121 #define BLE_ATT_EXCHANGE_MTU_RESP 0x03
122 #define BLE_ATT_FIND_INFORMATION_REQ 0x04
123 #define BLE_ATT_FIND_INFORMATION_RESP 0x05
124 #define BLE_ATT_FIND_BY_TYPE_REQ 0x06
125 #define BLE_ATT_FIND_BY_TYPE_RESP 0x07
126 #define BLE_ATT_READ_BY_TYPE_REQ 0x08
127 #define BLE_ATT_READ_BY_TYPE_RESP 0x09
128 #define BLE_ATT_READ_REQ 0x0a
129 #define BLE_ATT_READ_RESP 0x0b
130 #define BLE_ATT_READ_BLOB_REQ 0x0c
131 #define BLE_ATT_READ_BLOB_RESP 0x0d
132 #define BLE_ATT_READ_MULTIPLE_REQ 0x0e
133 #define BLE_ATT_READ_MULTIPLE_RESP 0x0f
134 #define BLE_ATT_READ_BY_GROUP_REQ 0x10
135 #define BLE_ATT_READ_BY_GROUP_RESP 0x11
136 #define BLE_ATT_WRITE_REQ 0x12
137 #define BLE_ATT_WRITE_RESP 0x13
138 #define BLE_ATT_WRITE_CMD 0x16
139 #define BLE_ATT_HANDLE_NOTIFICATION 0x1b
140 #define BLE_ATT_HANDLE_INDICATION 0x1d
141 #define BLE_ATT_HANDLE_CONFIRMATION 0x1e
142 #define BLE_ATT_SIGNED_WRITE_CMD 0x52
144 /* }}} Linux socket specific decls */
148 * Convert textual MAC presentation to array of bytes. In contrast to
149 * BlueZ conversion, accept colon or dash separated input as well as a
150 * dense format without separators (001122334455). We expect to use the
151 * library in an environment where colons are not always available as a
152 * separator in user provided specs, while users do want to use some
153 * separator for readability.
155 * TODO Instead of doing the actual conversion here (and dealing with
156 * BlueZ' internal byte order for device address bytes), we might as
157 * well just transform the input string to an output string, and always
158 * use the officially provided str2ba() conversion routine.
160 static int sr_bt_mac_text_to_bytes(const char *text, uint8_t *buf)
168 if (STORE_MAC_REVERSE)
171 while (len && endp && *endp) {
173 if (ACCEPT_NONSEP_MAC) {
175 numbuf[1] = endp[0] ? endp[1] : '\0';
179 v = strtol(ACCEPT_NONSEP_MAC ? numbuf : text, &endp, 16);
182 if (*endp != ':' && *endp != '-' && *endp != '\0')
184 if (v < 0 || v > 255)
186 if (STORE_MAC_REVERSE)
191 if (ACCEPT_NONSEP_MAC)
192 endp = (char *)text + (endp - numbuf);
193 if (*endp == ':' || *endp == '-')
198 sr_err("Failed to parse MAC, too few bytes in '%s'", text);
201 while (isspace(*endp))
204 sr_err("Failed to parse MAC, excess data in '%s'", text);
214 SR_PRIV const char *sr_bt_adapter_get_address(size_t idx)
217 struct hci_dev_info info;
220 rc = hci_devinfo(idx, &info);
221 sr_spew("DIAG: hci_devinfo(%zu) => rc %d", idx, rc);
225 rc = ba2str(&info.bdaddr, addr);
226 sr_spew("DIAG: ba2str() => rc %d", rc);
230 return g_strdup(addr);
237 /* User servicable options. */
238 sr_bt_scan_cb scan_cb;
240 sr_bt_data_cb data_cb;
243 char remote_addr[20];
244 size_t rfcomm_channel;
245 uint16_t read_handle;
246 uint16_t write_handle;
247 uint16_t cccd_handle;
249 /* Internal state. */
252 struct hci_filter orig_filter;
255 static int sr_bt_desc_open(struct sr_bt_desc *desc, int *id_ref);
256 static void sr_bt_desc_close(struct sr_bt_desc *desc);
257 static int sr_bt_check_socket_usable(struct sr_bt_desc *desc);
258 static ssize_t sr_bt_write_type(struct sr_bt_desc *desc, uint8_t type);
259 #if WITH_WRITE_TYPE_HANDLE
260 static ssize_t sr_bt_write_type_handle(struct sr_bt_desc *desc,
261 uint8_t type, uint16_t handle);
263 static ssize_t sr_bt_write_type_handle_bytes(struct sr_bt_desc *desc,
264 uint8_t type, uint16_t handle, const uint8_t *data, size_t len);
265 static ssize_t sr_bt_char_write_req(struct sr_bt_desc *desc,
266 uint16_t handle, const void *data, size_t len);
268 SR_PRIV struct sr_bt_desc *sr_bt_desc_new(void)
270 struct sr_bt_desc *desc;
272 desc = g_malloc0(sizeof(*desc));
282 SR_PRIV void sr_bt_desc_free(struct sr_bt_desc *desc)
287 sr_bt_desc_close(desc);
291 SR_PRIV int sr_bt_config_cb_scan(struct sr_bt_desc *desc,
292 sr_bt_scan_cb cb, void *cb_data)
298 desc->scan_cb_data = cb_data;
303 SR_PRIV int sr_bt_config_cb_data(struct sr_bt_desc *desc,
304 sr_bt_data_cb cb, void *cb_data)
310 desc->data_cb_data = cb_data;
315 SR_PRIV int sr_bt_config_addr_local(struct sr_bt_desc *desc, const char *addr)
323 if (!addr || !addr[0]) {
324 desc->local_addr[0] = '\0';
328 rc = sr_bt_mac_text_to_bytes(addr, &mac_bytes.b[0]);
332 rc = ba2str(&mac_bytes, desc->local_addr);
339 SR_PRIV int sr_bt_config_addr_remote(struct sr_bt_desc *desc, const char *addr)
347 if (!addr || !addr[0]) {
348 desc->remote_addr[0] = '\0';
352 rc = sr_bt_mac_text_to_bytes(addr, &mac_bytes.b[0]);
356 rc = ba2str(&mac_bytes, desc->remote_addr);
363 SR_PRIV int sr_bt_config_rfcomm(struct sr_bt_desc *desc, size_t channel)
368 desc->rfcomm_channel = channel;
373 SR_PRIV int sr_bt_config_notify(struct sr_bt_desc *desc,
374 uint16_t read_handle, uint16_t write_handle,
375 uint16_t cccd_handle, uint16_t cccd_value)
381 desc->read_handle = read_handle;
382 desc->write_handle = write_handle;
383 desc->cccd_handle = cccd_handle;
384 desc->cccd_value = cccd_value;
389 static int sr_bt_desc_open(struct sr_bt_desc *desc, int *id_ref)
398 if (desc->local_addr[0]) {
399 id = hci_devid(desc->local_addr);
400 } else if (desc->remote_addr[0]) {
401 str2ba(desc->remote_addr, &mac);
402 id = hci_get_route(&mac);
404 id = hci_get_route(NULL);
407 sr_err("devid failed");
414 sock = hci_open_dev(id);
416 perror("open HCI socket");
424 static void sr_bt_desc_close(struct sr_bt_desc *desc)
431 hci_close_dev(desc->fd);
440 #define EIR_NAME_COMPLETE 9
442 static int sr_bt_scan_prep(struct sr_bt_desc *desc)
445 uint8_t type, owntype, filter;
446 uint16_t ival, window;
450 struct hci_filter scan_filter;
455 /* TODO Replace magic values with symbolic identifiers. */
456 type = 0x01; /* LE public? */
457 ival = htobs(0x0010);
458 window = htobs(0x0010);
459 owntype = 0x00; /* any? */
462 rc = hci_le_set_scan_parameters(desc->fd,
463 type, ival, window, owntype, filter, timeout);
465 perror("set LE scan params");
472 rc = hci_le_set_scan_enable(desc->fd, enable, dup, timeout);
474 perror("set LE scan enable");
478 /* Save the current filter. For later restoration. */
479 slen = sizeof(desc->orig_filter);
480 rc = getsockopt(desc->fd, SOL_HCI, HCI_FILTER,
481 &desc->orig_filter, &slen);
483 perror("getsockopt(HCI_FILTER)");
487 hci_filter_clear(&scan_filter);
488 hci_filter_set_ptype(HCI_EVENT_PKT, &scan_filter);
489 hci_filter_set_event(EVT_LE_META_EVENT, &scan_filter);
490 rc = setsockopt(desc->fd, SOL_HCI, HCI_FILTER,
491 &scan_filter, sizeof(scan_filter));
493 perror("setsockopt(HCI_FILTER)");
500 static int sr_bt_scan_post(struct sr_bt_desc *desc)
509 /* Restore previous HCI filter. */
510 rc = setsockopt(desc->fd, SOL_HCI, HCI_FILTER,
511 &desc->orig_filter, sizeof(desc->orig_filter));
513 perror("setsockopt(HCI_FILTER)");
520 rc = hci_le_set_scan_enable(desc->fd, enable, dup, timeout);
527 static int sr_bt_scan_proc(struct sr_bt_desc *desc,
528 sr_bt_scan_cb scan_cb, void *cb_data,
529 uint8_t *data, size_t dlen, le_advertising_info *info)
538 if (type == EIR_NAME_COMPLETE) {
539 ba2str(&info->bdaddr, addr);
540 name = g_strndup((const char *)&data[1], dlen - 1);
542 scan_cb(cb_data, addr, name);
547 /* Unknown or unsupported type, ignore silently. */
551 SR_PRIV int sr_bt_scan_le(struct sr_bt_desc *desc, int duration)
555 uint8_t buf[HCI_MAX_EVENT_SIZE];
556 ssize_t rdlen, rdpos;
557 evt_le_meta_event *meta;
558 le_advertising_info *info;
564 sr_dbg("BLE scan (LE)");
566 rc = sr_bt_desc_open(desc, NULL);
570 rc = sr_bt_scan_prep(desc);
574 deadline = time(NULL);
575 deadline += duration;
576 while (time(NULL) <= deadline) {
578 if (sr_bt_check_socket_usable(desc) < 0)
580 rdlen = sr_bt_read(desc, buf, sizeof(buf));
587 if (rdlen < 1 + HCI_EVENT_HDR_SIZE)
589 meta = (void *)&buf[1 + HCI_EVENT_HDR_SIZE];
590 rdlen -= 1 + HCI_EVENT_HDR_SIZE;
591 if (meta->subevent != EVT_LE_ADVERTISING_REPORT)
593 info = (void *)&meta->data[1];
594 sr_spew("evt: type %d, len %d", info->evt_type, info->length);
599 while (rdpos < rdlen) {
600 datalen = info->data[rdpos];
601 dataptr = &info->data[1 + rdpos];
602 if (rdpos + 1 + datalen > info->length)
604 rdpos += 1 + datalen;
605 rc = sr_bt_scan_proc(desc,
606 desc->scan_cb, desc->scan_cb_data,
607 dataptr, datalen, info);
613 rc = sr_bt_scan_post(desc);
617 sr_bt_desc_close(desc);
622 SR_PRIV int sr_bt_scan_bt(struct sr_bt_desc *desc, int duration)
624 int dev_id, sock, rsp_max;
628 size_t rsp_count, idx;
634 sr_dbg("BLE scan (BT)");
636 sock = sr_bt_desc_open(desc, &dev_id);
641 info = g_malloc0(rsp_max * sizeof(*info));
642 flags = 0 /* | IREQ_CACHE_FLUSH */;
643 inq_rc = hci_inquiry(dev_id, duration, rsp_max, NULL, &info, flags);
645 perror("hci_inquiry");
648 for (idx = 0; idx < rsp_count; idx++) {
649 memset(addr, 0, sizeof(addr));
650 ba2str(&info[idx].bdaddr, addr);
651 memset(name, 0, sizeof(name));
652 if (hci_read_remote_name(sock, &info[idx].bdaddr, sizeof(name), name, 0) < 0)
653 snprintf(name, sizeof(name), "[unknown]");
655 desc->scan_cb(desc->scan_cb_data, addr, name);
659 sr_bt_desc_close(desc);
665 /* {{{ connect/disconnect */
667 SR_PRIV int sr_bt_connect_ble(struct sr_bt_desc *desc)
669 struct sockaddr_l2 sl2;
676 if (!desc->remote_addr[0])
678 sr_dbg("BLE connect, remote addr %s", desc->remote_addr);
680 s = socket(AF_BLUETOOTH, SOCK_SEQPACKET, 0);
682 perror("socket create");
687 memset(&sl2, 0, sizeof(sl2));
688 sl2.l2_family = AF_BLUETOOTH;
690 if (desc->local_addr[0])
691 str2ba(desc->local_addr, &mac);
694 memcpy(&sl2.l2_bdaddr, &mac, sizeof(sl2.l2_bdaddr));
695 sl2.l2_cid = L2CAP_FC_CONNLESS;
696 sl2.l2_bdaddr_type = BDADDR_LE_PUBLIC;
697 ret = bind(s, (void *)&sl2, sizeof(sl2));
704 struct bt_security buf = {
705 .level = BT_SECURITY_LOW,
708 ret = setsockopt(s, SOL_BLUETOOTH, BT_SECURITY, &buf, sizeof(buf));
710 perror("setsockopt");
715 deadline = g_get_monotonic_time();
716 deadline += CONNECT_BLE_TIMEOUT * 1000 * 1000;
717 str2ba(desc->remote_addr, &mac);
718 memcpy(&sl2.l2_bdaddr, &mac, sizeof(sl2.l2_bdaddr));
719 sl2.l2_bdaddr_type = BDADDR_LE_PUBLIC;
720 ret = connect(s, (void *)&sl2, sizeof(sl2));
722 * Cope with "in progress" condition. Keep polling the status
723 * until connect() completes, then get the error by means of
724 * getsockopt(). See the connect(2) manpage for details.
726 if (ret < 0 && errno == EINPROGRESS) {
727 struct pollfd fds[1];
732 * We seem to get here ("connect in progress") even when
733 * the specified peer is not around at all. Which results
734 * in extended periods of time where nothing happens, and
735 * an application timeout seems to be required.
737 sr_spew("in progress ...");
740 memset(fds, 0, sizeof(fds));
742 fds[0].events = POLLOUT;
743 ret = poll(fds, ARRAY_SIZE(fds), -1);
750 if (!(fds[0].revents & POLLOUT))
752 if (g_get_monotonic_time() >= deadline) {
753 sr_warn("Connect attempt timed out");
757 memset(fds, 0, sizeof(fds));
759 fds[0].events = POLLNVAL;
760 ret = poll(fds, 1, 0);
762 perror("poll(INVAL)");
766 /* socket fd is invalid(?) */
771 solen = sizeof(soerror);
772 ret = getsockopt(s, SOL_SOCKET, SO_ERROR, &soerror, &solen);
774 perror("getsockopt(SO_ERROR)");
778 /* connect(2) failed, SO_ERROR has the error code. */
780 perror("connect(PROGRESS)");
785 * TODO Get the receive MTU here?
786 * getsockopt(SOL_BLUETOOTH, BT_RCVMTU, u16);
797 SR_PRIV int sr_bt_connect_rfcomm(struct sr_bt_desc *desc)
799 struct sockaddr_rc addr;
804 if (!desc->remote_addr[0])
806 sr_dbg("RFCOMM connect, remote addr %s, channel %zu",
807 desc->remote_addr, desc->rfcomm_channel);
809 if (!desc->rfcomm_channel)
810 desc->rfcomm_channel = 1;
812 fd = socket(AF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
819 memset(&addr, 0, sizeof(addr));
820 addr.rc_family = AF_BLUETOOTH;
821 str2ba(desc->remote_addr, &addr.rc_bdaddr);
822 addr.rc_channel = desc->rfcomm_channel;
823 rc = connect(fd, (struct sockaddr *)&addr, sizeof(addr));
828 sr_spew("connected");
833 SR_PRIV void sr_bt_disconnect(struct sr_bt_desc *desc)
835 sr_dbg("BLE disconnect");
839 sr_bt_desc_close(desc);
842 static int sr_bt_check_socket_usable(struct sr_bt_desc *desc)
844 struct pollfd fds[1];
852 memset(fds, 0, sizeof(fds));
853 fds[0].fd = desc->fd;
854 fds[0].events = POLLERR | POLLHUP;
855 ret = poll(fds, ARRAY_SIZE(fds), 0);
860 if (fds[0].revents & POLLHUP)
862 if (fds[0].revents & POLLERR)
864 if (fds[0].revents & POLLNVAL)
870 /* }}} connect/disconnect */
871 /* {{{ indication/notification */
873 SR_PRIV int sr_bt_start_notify(struct sr_bt_desc *desc)
875 uint8_t buf[sizeof(desc->cccd_value)];
880 sr_dbg("BLE start notify");
882 if (sr_bt_check_socket_usable(desc) < 0)
885 bt_put_le16(desc->cccd_value, buf);
886 wrlen = sr_bt_char_write_req(desc, desc->cccd_handle, buf, sizeof(buf));
887 if (wrlen != sizeof(buf))
893 SR_PRIV int sr_bt_check_notify(struct sr_bt_desc *desc)
898 uint16_t packet_handle;
899 uint8_t *packet_data;
905 if (sr_bt_check_socket_usable(desc) < 0)
908 /* Get another message from the Bluetooth socket. */
909 rdlen = sr_bt_read(desc, buf, sizeof(buf));
915 /* Get header fields and references to the payload data. */
917 packet_handle = 0x0000;
921 packet_type = buf[0];
923 packet_handle = bt_get_le16(&buf[1]);
924 packet_data = &buf[3];
925 packet_dlen = rdlen - 3;
928 /* Dispatch according to the message type. */
929 switch (packet_type) {
930 case BLE_ATT_ERROR_RESP:
931 sr_spew("read() len %zd, type 0x%02x (%s)", rdlen, buf[0], "error response");
934 case BLE_ATT_WRITE_RESP:
935 sr_spew("read() len %zd, type 0x%02x (%s)", rdlen, buf[0], "write response");
938 case BLE_ATT_HANDLE_INDICATION:
939 sr_spew("read() len %zd, type 0x%02x (%s)", rdlen, buf[0], "handle indication");
940 sr_bt_write_type(desc, BLE_ATT_HANDLE_CONFIRMATION);
941 if (packet_handle != desc->read_handle)
947 return desc->data_cb(desc->data_cb_data, packet_data, packet_dlen);
948 case BLE_ATT_HANDLE_NOTIFICATION:
949 sr_spew("read() len %zd, type 0x%02x (%s)", rdlen, buf[0], "handle notification");
950 if (packet_handle != desc->read_handle)
956 return desc->data_cb(desc->data_cb_data, packet_data, packet_dlen);
958 sr_spew("unsupported type 0x%02x", packet_type);
965 /* }}} indication/notification */
968 SR_PRIV ssize_t sr_bt_write(struct sr_bt_desc *desc,
969 const void *data, size_t len)
976 if (sr_bt_check_socket_usable(desc) < 0)
979 /* Send TX data to the writable characteristics for BLE UART services. */
980 if (desc->write_handle)
981 return sr_bt_char_write_req(desc, desc->write_handle, data, len);
983 /* Send raw TX data to the RFCOMM socket for BT Classic channels. */
984 return write(desc->fd, data, len);
987 static ssize_t sr_bt_write_type(struct sr_bt_desc *desc, uint8_t type)
996 if (sr_bt_check_socket_usable(desc) < 0)
999 wrlen = write(desc->fd, &type, sizeof(type));
1002 if (wrlen < (ssize_t)sizeof(type))
1008 #if WITH_WRITE_TYPE_HANDLE
1009 static ssize_t sr_bt_write_type_handle(struct sr_bt_desc *desc,
1010 uint8_t type, uint16_t handle)
1012 return sr_bt_write_type_handle_bytes(desc, type, handle, NULL, 0);
1016 static ssize_t sr_bt_write_type_handle_bytes(struct sr_bt_desc *desc,
1017 uint8_t type, uint16_t handle, const uint8_t *data, size_t len)
1019 uint8_t header[sizeof(uint8_t) + sizeof(uint16_t)];
1020 struct iovec iov[2] = {
1021 { .iov_base = header, .iov_len = sizeof(header), },
1022 { .iov_base = (void *)data, .iov_len = len, },
1031 if (sr_bt_check_socket_usable(desc) < 0)
1035 bt_put_le16(handle, &header[1]);
1038 wrlen = writev(desc->fd, iov, ARRAY_SIZE(iov));
1040 wrlen = write(desc->fd, header, sizeof(header));
1044 if (wrlen < (ssize_t)sizeof(header))
1046 wrlen -= sizeof(header);
1051 /* Returns negative upon error, or returns the number of _payload_ bytes written. */
1052 static ssize_t sr_bt_char_write_req(struct sr_bt_desc *desc,
1053 uint16_t handle, const void *data, size_t len)
1055 return sr_bt_write_type_handle_bytes(desc, BLE_ATT_WRITE_REQ,
1059 SR_PRIV ssize_t sr_bt_read(struct sr_bt_desc *desc, void *data, size_t len)
1061 struct pollfd fds[1];
1070 if (sr_bt_check_socket_usable(desc) < 0)
1073 memset(fds, 0, sizeof(fds));
1074 fds[0].fd = desc->fd;
1075 fds[0].events = POLLIN;
1076 ret = poll(fds, ARRAY_SIZE(fds), 0);
1081 if (!(fds[0].revents & POLLIN))
1084 rdlen = read(desc->fd, data, len);
1089 /* }}} indication/notification */