1 /******************************************************************************
2  *
3  *  Copyright 2009-2012 Broadcom Corporation
4  *
5  *  Licensed under the Apache License, Version 2.0 (the "License");
6  *  you may not use this file except in compliance with the License.
7  *  You may obtain a copy of the License at:
8  *
9  *  http://www.apache.org/licenses/LICENSE-2.0
10  *
11  *  Unless required by applicable law or agreed to in writing, software
12  *  distributed under the License is distributed on an "AS IS" BASIS,
13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  *  See the License for the specific language governing permissions and
15  *  limitations under the License.
16  *
17  ******************************************************************************/
18 
19 /*****************************************************************************
20  *
21  *  Filename:      uipc.cc
22  *
23  *  Description:   UIPC implementation for fluoride
24  *
25  *****************************************************************************/
26 
27 #include <errno.h>
28 #include <fcntl.h>
29 #include <signal.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <sys/mman.h>
34 #include <sys/poll.h>
35 #include <sys/prctl.h>
36 #include <sys/select.h>
37 #include <sys/socket.h>
38 #include <sys/stat.h>
39 #include <sys/un.h>
40 #include <unistd.h>
41 #include <mutex>
42 #include <set>
43 
44 #include "audio_a2dp_hw/include/audio_a2dp_hw.h"
45 #include "bt_common.h"
46 #include "bt_types.h"
47 #include "bt_utils.h"
48 #include "osi/include/osi.h"
49 #include "osi/include/socket_utils/sockets.h"
50 #include "uipc.h"
51 
52 /*****************************************************************************
53  *  Constants & Macros
54  *****************************************************************************/
55 
56 #define PCM_FILENAME "/data/test.pcm"
57 
58 #define MAX(a, b) ((a) > (b) ? (a) : (b))
59 
60 #define CASE_RETURN_STR(const) \
61   case const:                  \
62     return #const;
63 
64 #define UIPC_DISCONNECTED (-1)
65 
66 #define SAFE_FD_ISSET(fd, set) (((fd) == -1) ? false : FD_ISSET((fd), (set)))
67 
68 #define UIPC_FLUSH_BUFFER_SIZE 1024
69 
70 /*****************************************************************************
71  *  Local type definitions
72  *****************************************************************************/
73 
74 typedef enum {
75   UIPC_TASK_FLAG_DISCONNECT_CHAN = 0x1,
76 } tUIPC_TASK_FLAGS;
77 
78 /*****************************************************************************
79  *  Static functions
80  *****************************************************************************/
81 static int uipc_close_ch_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id);
82 
83 /*****************************************************************************
84  *  Externs
85  *****************************************************************************/
86 
87 /*****************************************************************************
88  *   Helper functions
89  *****************************************************************************/
90 
91 const char* dump_uipc_event(tUIPC_EVENT event) {
92   switch (event) {
93     CASE_RETURN_STR(UIPC_OPEN_EVT)
94     CASE_RETURN_STR(UIPC_CLOSE_EVT)
95     CASE_RETURN_STR(UIPC_RX_DATA_EVT)
96     CASE_RETURN_STR(UIPC_RX_DATA_READY_EVT)
97     CASE_RETURN_STR(UIPC_TX_DATA_READY_EVT)
98     default:
99       return "UNKNOWN MSG ID";
100   }
101 }
102 
103 /*****************************************************************************
104  *   socket helper functions
105  ****************************************************************************/
106 
107 static inline int create_server_socket(const char* name) {
108   int s = socket(AF_LOCAL, SOCK_STREAM, 0);
109   if (s < 0) return -1;
110 
111   BTIF_TRACE_EVENT("create_server_socket %s", name);
112 
113   if (osi_socket_local_server_bind(s, name,
114 #if defined(OS_GENERIC)
115                                    ANDROID_SOCKET_NAMESPACE_FILESYSTEM
116 #else   // !defined(OS_GENERIC)
117                                    ANDROID_SOCKET_NAMESPACE_ABSTRACT
118 #endif  // defined(OS_GENERIC)
119                                    ) < 0) {
120     BTIF_TRACE_EVENT("socket failed to create (%s)", strerror(errno));
121     close(s);
122     return -1;
123   }
124 
125   if (listen(s, 5) < 0) {
126     BTIF_TRACE_EVENT("listen failed", strerror(errno));
127     close(s);
128     return -1;
129   }
130 
131   BTIF_TRACE_EVENT("created socket fd %d", s);
132   return s;
133 }
134 
135 static int accept_server_socket(int sfd) {
136   struct sockaddr_un remote;
137   struct pollfd pfd;
138   int fd;
139   socklen_t len = sizeof(struct sockaddr_un);
140 
141   BTIF_TRACE_EVENT("accept fd %d", sfd);
142 
143   /* make sure there is data to process */
144   pfd.fd = sfd;
145   pfd.events = POLLIN;
146 
147   int poll_ret;
148   OSI_NO_INTR(poll_ret = poll(&pfd, 1, 0));
149   if (poll_ret == 0) {
150     BTIF_TRACE_WARNING("accept poll timeout");
151     return -1;
152   }
153 
154   // BTIF_TRACE_EVENT("poll revents 0x%x", pfd.revents);
155 
156   OSI_NO_INTR(fd = accept(sfd, (struct sockaddr*)&remote, &len));
157   if (fd == -1) {
158     BTIF_TRACE_ERROR("sock accept failed (%s)", strerror(errno));
159     return -1;
160   }
161 
162   // match socket buffer size option with client
163   const int size = AUDIO_STREAM_OUTPUT_BUFFER_SZ;
164   int ret =
165       setsockopt(fd, SOL_SOCKET, SO_RCVBUF, (char*)&size, (int)sizeof(size));
166   if (ret < 0) {
167     BTIF_TRACE_ERROR("setsockopt failed (%s)", strerror(errno));
168   }
169 
170   // BTIF_TRACE_EVENT("new fd %d", fd);
171 
172   return fd;
173 }
174 
175 /*****************************************************************************
176  *
177  *   uipc helper functions
178  *
179  ****************************************************************************/
180 
181 static int uipc_main_init(tUIPC_STATE& uipc) {
182   int i;
183 
184   BTIF_TRACE_EVENT("### uipc_main_init ###");
185 
186   uipc.tid = 0;
187   uipc.running = 0;
188   memset(&uipc.active_set, 0, sizeof(uipc.active_set));
189   memset(&uipc.read_set, 0, sizeof(uipc.read_set));
190   uipc.max_fd = 0;
191   memset(&uipc.signal_fds, 0, sizeof(uipc.signal_fds));
192   memset(&uipc.ch, 0, sizeof(uipc.ch));
193 
194   /* setup interrupt socket pair */
195   if (socketpair(AF_UNIX, SOCK_STREAM, 0, uipc.signal_fds) < 0) {
196     return -1;
197   }
198 
199   FD_SET(uipc.signal_fds[0], &uipc.active_set);
200   uipc.max_fd = MAX(uipc.max_fd, uipc.signal_fds[0]);
201 
202   for (i = 0; i < UIPC_CH_NUM; i++) {
203     tUIPC_CHAN* p = &uipc.ch[i];
204     p->srvfd = UIPC_DISCONNECTED;
205     p->fd = UIPC_DISCONNECTED;
206     p->task_evt_flags = 0;
207     p->cback = NULL;
208   }
209 
210   return 0;
211 }
212 
213 void uipc_main_cleanup(tUIPC_STATE& uipc) {
214   int i;
215 
216   BTIF_TRACE_EVENT("uipc_main_cleanup");
217 
218   close(uipc.signal_fds[0]);
219   close(uipc.signal_fds[1]);
220 
221   /* close any open channels */
222   for (i = 0; i < UIPC_CH_NUM; i++) uipc_close_ch_locked(uipc, i);
223 }
224 
225 /* check pending events in read task */
226 static void uipc_check_task_flags_locked(tUIPC_STATE& uipc) {
227   int i;
228 
229   for (i = 0; i < UIPC_CH_NUM; i++) {
230     if (uipc.ch[i].task_evt_flags & UIPC_TASK_FLAG_DISCONNECT_CHAN) {
231       uipc.ch[i].task_evt_flags &= ~UIPC_TASK_FLAG_DISCONNECT_CHAN;
232       uipc_close_ch_locked(uipc, i);
233     }
234 
235     /* add here */
236   }
237 }
238 
239 static int uipc_check_fd_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id) {
240   if (ch_id >= UIPC_CH_NUM) return -1;
241 
242   // BTIF_TRACE_EVENT("CHECK SRVFD %d (ch %d)", uipc.ch[ch_id].srvfd,
243   // ch_id);
244 
245   if (SAFE_FD_ISSET(uipc.ch[ch_id].srvfd, &uipc.read_set)) {
246     BTIF_TRACE_EVENT("INCOMING CONNECTION ON CH %d", ch_id);
247 
248     // Close the previous connection
249     if (uipc.ch[ch_id].fd != UIPC_DISCONNECTED) {
250       BTIF_TRACE_EVENT("CLOSE CONNECTION (FD %d)", uipc.ch[ch_id].fd);
251       close(uipc.ch[ch_id].fd);
252       FD_CLR(uipc.ch[ch_id].fd, &uipc.active_set);
253       uipc.ch[ch_id].fd = UIPC_DISCONNECTED;
254     }
255 
256     uipc.ch[ch_id].fd = accept_server_socket(uipc.ch[ch_id].srvfd);
257 
258     BTIF_TRACE_EVENT("NEW FD %d", uipc.ch[ch_id].fd);
259 
260     if ((uipc.ch[ch_id].fd >= 0) && uipc.ch[ch_id].cback) {
261       /*  if we have a callback we should add this fd to the active set
262           and notify user with callback event */
263       BTIF_TRACE_EVENT("ADD FD %d TO ACTIVE SET", uipc.ch[ch_id].fd);
264       FD_SET(uipc.ch[ch_id].fd, &uipc.active_set);
265       uipc.max_fd = MAX(uipc.max_fd, uipc.ch[ch_id].fd);
266     }
267 
268     if (uipc.ch[ch_id].fd < 0) {
269       BTIF_TRACE_ERROR("FAILED TO ACCEPT CH %d", ch_id);
270       return -1;
271     }
272 
273     if (uipc.ch[ch_id].cback) uipc.ch[ch_id].cback(ch_id, UIPC_OPEN_EVT);
274   }
275 
276   // BTIF_TRACE_EVENT("CHECK FD %d (ch %d)", uipc.ch[ch_id].fd, ch_id);
277 
278   if (SAFE_FD_ISSET(uipc.ch[ch_id].fd, &uipc.read_set)) {
279     // BTIF_TRACE_EVENT("INCOMING DATA ON CH %d", ch_id);
280 
281     if (uipc.ch[ch_id].cback)
282       uipc.ch[ch_id].cback(ch_id, UIPC_RX_DATA_READY_EVT);
283   }
284   return 0;
285 }
286 
287 static void uipc_check_interrupt_locked(tUIPC_STATE& uipc) {
288   if (SAFE_FD_ISSET(uipc.signal_fds[0], &uipc.read_set)) {
289     char sig_recv = 0;
290     OSI_NO_INTR(
291         recv(uipc.signal_fds[0], &sig_recv, sizeof(sig_recv), MSG_WAITALL));
292   }
293 }
294 
295 static inline void uipc_wakeup_locked(tUIPC_STATE& uipc) {
296   char sig_on = 1;
297   BTIF_TRACE_EVENT("UIPC SEND WAKE UP");
298 
299   OSI_NO_INTR(send(uipc.signal_fds[1], &sig_on, sizeof(sig_on), 0));
300 }
301 
302 static int uipc_setup_server_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id,
303                                     const char* name, tUIPC_RCV_CBACK* cback) {
304   int fd;
305 
306   BTIF_TRACE_EVENT("SETUP CHANNEL SERVER %d", ch_id);
307 
308   if (ch_id >= UIPC_CH_NUM) return -1;
309 
310   std::lock_guard<std::recursive_mutex> guard(uipc.mutex);
311 
312   fd = create_server_socket(name);
313 
314   if (fd < 0) {
315     BTIF_TRACE_ERROR("failed to setup %s", name, strerror(errno));
316     return -1;
317   }
318 
319   BTIF_TRACE_EVENT("ADD SERVER FD TO ACTIVE SET %d", fd);
320   FD_SET(fd, &uipc.active_set);
321   uipc.max_fd = MAX(uipc.max_fd, fd);
322 
323   uipc.ch[ch_id].srvfd = fd;
324   uipc.ch[ch_id].cback = cback;
325   uipc.ch[ch_id].read_poll_tmo_ms = DEFAULT_READ_POLL_TMO_MS;
326 
327   /* trigger main thread to update read set */
328   uipc_wakeup_locked(uipc);
329 
330   return 0;
331 }
332 
333 static void uipc_flush_ch_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id) {
334   char buf[UIPC_FLUSH_BUFFER_SIZE];
335   struct pollfd pfd;
336 
337   pfd.events = POLLIN;
338   pfd.fd = uipc.ch[ch_id].fd;
339 
340   if (uipc.ch[ch_id].fd == UIPC_DISCONNECTED) {
341     BTIF_TRACE_EVENT("%s() - fd disconnected. Exiting", __func__);
342     return;
343   }
344 
345   while (1) {
346     int ret;
347     OSI_NO_INTR(ret = poll(&pfd, 1, 1));
348     if (ret == 0) {
349       BTIF_TRACE_VERBOSE("%s(): poll() timeout - nothing to do. Exiting",
350                          __func__);
351       return;
352     }
353     if (ret < 0) {
354       BTIF_TRACE_WARNING(
355           "%s() - poll() failed: return %d errno %d (%s). Exiting", __func__,
356           ret, errno, strerror(errno));
357       return;
358     }
359     BTIF_TRACE_VERBOSE("%s() - polling fd %d, revents: 0x%x, ret %d", __func__,
360                        pfd.fd, pfd.revents, ret);
361     if (pfd.revents & (POLLERR | POLLHUP)) {
362       BTIF_TRACE_WARNING("%s() - POLLERR or POLLHUP. Exiting", __func__);
363       return;
364     }
365 
366     /* read sufficiently large buffer to ensure flush empties socket faster than
367        it is getting refilled */
368     (void)read(pfd.fd, &buf, UIPC_FLUSH_BUFFER_SIZE);
369   }
370 }
371 
372 static void uipc_flush_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id) {
373   if (ch_id >= UIPC_CH_NUM) return;
374 
375   switch (ch_id) {
376     case UIPC_CH_ID_AV_CTRL:
377       uipc_flush_ch_locked(uipc, UIPC_CH_ID_AV_CTRL);
378       break;
379 
380     case UIPC_CH_ID_AV_AUDIO:
381       uipc_flush_ch_locked(uipc, UIPC_CH_ID_AV_AUDIO);
382       break;
383   }
384 }
385 
386 static int uipc_close_ch_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id) {
387   int wakeup = 0;
388 
389   BTIF_TRACE_EVENT("CLOSE CHANNEL %d", ch_id);
390 
391   if (ch_id >= UIPC_CH_NUM) return -1;
392 
393   if (uipc.ch[ch_id].srvfd != UIPC_DISCONNECTED) {
394     BTIF_TRACE_EVENT("CLOSE SERVER (FD %d)", uipc.ch[ch_id].srvfd);
395     close(uipc.ch[ch_id].srvfd);
396     FD_CLR(uipc.ch[ch_id].srvfd, &uipc.active_set);
397     uipc.ch[ch_id].srvfd = UIPC_DISCONNECTED;
398     wakeup = 1;
399   }
400 
401   if (uipc.ch[ch_id].fd != UIPC_DISCONNECTED) {
402     BTIF_TRACE_EVENT("CLOSE CONNECTION (FD %d)", uipc.ch[ch_id].fd);
403     close(uipc.ch[ch_id].fd);
404     FD_CLR(uipc.ch[ch_id].fd, &uipc.active_set);
405     uipc.ch[ch_id].fd = UIPC_DISCONNECTED;
406     wakeup = 1;
407   }
408 
409   /* notify this connection is closed */
410   if (uipc.ch[ch_id].cback) uipc.ch[ch_id].cback(ch_id, UIPC_CLOSE_EVT);
411 
412   /* trigger main thread update if something was updated */
413   if (wakeup) uipc_wakeup_locked(uipc);
414 
415   return 0;
416 }
417 
418 void uipc_close_locked(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id) {
419   if (uipc.ch[ch_id].srvfd == UIPC_DISCONNECTED) {
420     BTIF_TRACE_EVENT("CHANNEL %d ALREADY CLOSED", ch_id);
421     return;
422   }
423 
424   /* schedule close on this channel */
425   uipc.ch[ch_id].task_evt_flags |= UIPC_TASK_FLAG_DISCONNECT_CHAN;
426   uipc_wakeup_locked(uipc);
427 }
428 
429 static void* uipc_read_task(void* arg) {
430   tUIPC_STATE& uipc = *((tUIPC_STATE*)arg);
431   int ch_id;
432   int result;
433 
434   prctl(PR_SET_NAME, (unsigned long)"uipc-main", 0, 0, 0);
435 
436   raise_priority_a2dp(TASK_UIPC_READ);
437 
438   while (uipc.running) {
439     uipc.read_set = uipc.active_set;
440 
441     result = select(uipc.max_fd + 1, &uipc.read_set, NULL, NULL, NULL);
442 
443     if (result == 0) {
444       BTIF_TRACE_EVENT("select timeout");
445       continue;
446     }
447     if (result < 0) {
448       if (errno != EINTR) {
449         BTIF_TRACE_EVENT("select failed %s", strerror(errno));
450       }
451       continue;
452     }
453 
454     {
455       std::lock_guard<std::recursive_mutex> guard(uipc.mutex);
456 
457       /* clear any wakeup interrupt */
458       uipc_check_interrupt_locked(uipc);
459 
460       /* check pending task events */
461       uipc_check_task_flags_locked(uipc);
462 
463       /* make sure we service audio channel first */
464       uipc_check_fd_locked(uipc, UIPC_CH_ID_AV_AUDIO);
465 
466       /* check for other connections */
467       for (ch_id = 0; ch_id < UIPC_CH_NUM; ch_id++) {
468         if (ch_id != UIPC_CH_ID_AV_AUDIO) uipc_check_fd_locked(uipc, ch_id);
469       }
470     }
471   }
472 
473   BTIF_TRACE_EVENT("UIPC READ THREAD EXITING");
474 
475   uipc_main_cleanup(uipc);
476 
477   uipc.tid = 0;
478 
479   BTIF_TRACE_EVENT("UIPC READ THREAD DONE");
480 
481   return nullptr;
482 }
483 
484 int uipc_start_main_server_thread(tUIPC_STATE& uipc) {
485   uipc.running = 1;
486 
487   if (pthread_create(&uipc.tid, (const pthread_attr_t*)NULL, uipc_read_task,
488                      &uipc) != 0) {
489     BTIF_TRACE_ERROR("uipc_thread_create pthread_create failed:%d", errno);
490     return -1;
491   }
492 
493   return 0;
494 }
495 
496 /* blocking call */
497 void uipc_stop_main_server_thread(tUIPC_STATE& uipc) {
498   /* request shutdown of read thread */
499   {
500     std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
501     uipc.running = 0;
502     uipc_wakeup_locked(uipc);
503   }
504 
505   /* wait until read thread is fully terminated */
506   /* tid might hold pointer value where it's value
507      is negative vaule with singed bit is set, so
508      corrected the logic to check zero or non zero */
509   if (uipc.tid) pthread_join(uipc.tid, NULL);
510 }
511 
512 /*******************************************************************************
513  **
514  ** Function         UIPC_Init
515  **
516  ** Description      Initialize UIPC module
517  **
518  ** Returns          void
519  **
520  ******************************************************************************/
521 std::unique_ptr<tUIPC_STATE> UIPC_Init() {
522   std::unique_ptr<tUIPC_STATE> uipc = std::make_unique<tUIPC_STATE>();
523   BTIF_TRACE_DEBUG("UIPC_Init");
524 
525   std::lock_guard<std::recursive_mutex> lock(uipc->mutex);
526 
527   uipc_main_init(*uipc);
528   uipc_start_main_server_thread(*uipc);
529 
530   return uipc;
531 }
532 
533 /*******************************************************************************
534  **
535  ** Function         UIPC_Open
536  **
537  ** Description      Open UIPC interface
538  **
539  ** Returns          true in case of success, false in case of failure.
540  **
541  ******************************************************************************/
542 bool UIPC_Open(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id, tUIPC_RCV_CBACK* p_cback,
543                const char* socket_path) {
544   BTIF_TRACE_DEBUG("UIPC_Open : ch_id %d, p_cback %x", ch_id, p_cback);
545 
546   std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
547 
548   if (ch_id >= UIPC_CH_NUM) {
549     return false;
550   }
551 
552   if (uipc.ch[ch_id].srvfd != UIPC_DISCONNECTED) {
553     BTIF_TRACE_EVENT("CHANNEL %d ALREADY OPEN", ch_id);
554     return 0;
555   }
556 
557   uipc_setup_server_locked(uipc, ch_id, socket_path, p_cback);
558 
559   return true;
560 }
561 
562 /*******************************************************************************
563  **
564  ** Function         UIPC_Close
565  **
566  ** Description      Close UIPC interface
567  **
568  ** Returns          void
569  **
570  ******************************************************************************/
571 void UIPC_Close(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id) {
572   BTIF_TRACE_DEBUG("UIPC_Close : ch_id %d", ch_id);
573 
574   /* special case handling uipc shutdown */
575   if (ch_id != UIPC_CH_ID_ALL) {
576     std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
577     uipc_close_locked(uipc, ch_id);
578     return;
579   }
580 
581   BTIF_TRACE_DEBUG("UIPC_Close : waiting for shutdown to complete");
582   uipc_stop_main_server_thread(uipc);
583   BTIF_TRACE_DEBUG("UIPC_Close : shutdown complete");
584 }
585 
586 /*******************************************************************************
587  **
588  ** Function         UIPC_Send
589  **
590  ** Description      Called to transmit a message over UIPC.
591  **
592  ** Returns          true in case of success, false in case of failure.
593  **
594  ******************************************************************************/
595 bool UIPC_Send(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id,
596                UNUSED_ATTR uint16_t msg_evt, const uint8_t* p_buf,
597                uint16_t msglen) {
598   BTIF_TRACE_DEBUG("UIPC_Send : ch_id:%d %d bytes", ch_id, msglen);
599 
600   std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
601 
602   ssize_t ret;
603   OSI_NO_INTR(ret = write(uipc.ch[ch_id].fd, p_buf, msglen));
604   if (ret < 0) {
605     BTIF_TRACE_ERROR("failed to write (%s)", strerror(errno));
606   }
607 
608   return false;
609 }
610 
611 /*******************************************************************************
612  **
613  ** Function         UIPC_Read
614  **
615  ** Description      Called to read a message from UIPC.
616  **
617  ** Returns          return the number of bytes read.
618  **
619  ******************************************************************************/
620 
621 uint32_t UIPC_Read(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id,
622                    UNUSED_ATTR uint16_t* p_msg_evt, uint8_t* p_buf,
623                    uint32_t len) {
624   if (ch_id >= UIPC_CH_NUM) {
625     BTIF_TRACE_ERROR("UIPC_Read : invalid ch id %d", ch_id);
626     return 0;
627   }
628 
629   int n_read = 0;
630   int fd = uipc.ch[ch_id].fd;
631   struct pollfd pfd;
632 
633   if (fd == UIPC_DISCONNECTED) {
634     BTIF_TRACE_ERROR("UIPC_Read : channel %d closed", ch_id);
635     return 0;
636   }
637 
638   while (n_read < (int)len) {
639     pfd.fd = fd;
640     pfd.events = POLLIN | POLLHUP;
641 
642     /* make sure there is data prior to attempting read to avoid blocking
643        a read for more than poll timeout */
644 
645     int poll_ret;
646     OSI_NO_INTR(poll_ret = poll(&pfd, 1, uipc.ch[ch_id].read_poll_tmo_ms));
647     if (poll_ret == 0) {
648       BTIF_TRACE_WARNING("poll timeout (%d ms)",
649                          uipc.ch[ch_id].read_poll_tmo_ms);
650       break;
651     }
652     if (poll_ret < 0) {
653       BTIF_TRACE_ERROR("%s(): poll() failed: return %d errno %d (%s)", __func__,
654                        poll_ret, errno, strerror(errno));
655       break;
656     }
657 
658     // BTIF_TRACE_EVENT("poll revents %x", pfd.revents);
659 
660     if (pfd.revents & (POLLHUP | POLLNVAL)) {
661       BTIF_TRACE_WARNING("poll : channel detached remotely");
662       std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
663       uipc_close_locked(uipc, ch_id);
664       return 0;
665     }
666 
667     ssize_t n;
668     OSI_NO_INTR(n = recv(fd, p_buf + n_read, len - n_read, 0));
669 
670     // BTIF_TRACE_EVENT("read %d bytes", n);
671 
672     if (n == 0) {
673       BTIF_TRACE_WARNING("UIPC_Read : channel detached remotely");
674       std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
675       uipc_close_locked(uipc, ch_id);
676       return 0;
677     }
678 
679     if (n < 0) {
680       BTIF_TRACE_WARNING("UIPC_Read : read failed (%s)", strerror(errno));
681       return 0;
682     }
683 
684     n_read += n;
685   }
686 
687   return n_read;
688 }
689 
690 /*******************************************************************************
691  *
692  * Function         UIPC_Ioctl
693  *
694  * Description      Called to control UIPC.
695  *
696  * Returns          void
697  *
698  ******************************************************************************/
699 
700 extern bool UIPC_Ioctl(tUIPC_STATE& uipc, tUIPC_CH_ID ch_id, uint32_t request,
701                        void* param) {
702   BTIF_TRACE_DEBUG("#### UIPC_Ioctl : ch_id %d, request %d ####", ch_id,
703                    request);
704   std::lock_guard<std::recursive_mutex> lock(uipc.mutex);
705 
706   switch (request) {
707     case UIPC_REQ_RX_FLUSH:
708       uipc_flush_locked(uipc, ch_id);
709       break;
710 
711     case UIPC_REG_CBACK:
712       // BTIF_TRACE_EVENT("register callback ch %d srvfd %d, fd %d", ch_id,
713       // uipc.ch[ch_id].srvfd, uipc.ch[ch_id].fd);
714       uipc.ch[ch_id].cback = (tUIPC_RCV_CBACK*)param;
715       break;
716 
717     case UIPC_REG_REMOVE_ACTIVE_READSET:
718       /* user will read data directly and not use select loop */
719       if (uipc.ch[ch_id].fd != UIPC_DISCONNECTED) {
720         /* remove this channel from active set */
721         FD_CLR(uipc.ch[ch_id].fd, &uipc.active_set);
722 
723         /* refresh active set */
724         uipc_wakeup_locked(uipc);
725       }
726       break;
727 
728     case UIPC_SET_READ_POLL_TMO:
729       uipc.ch[ch_id].read_poll_tmo_ms = (intptr_t)param;
730       BTIF_TRACE_EVENT("UIPC_SET_READ_POLL_TMO : CH %d, TMO %d ms", ch_id,
731                        uipc.ch[ch_id].read_poll_tmo_ms);
732       break;
733 
734     default:
735       BTIF_TRACE_EVENT("UIPC_Ioctl : request not handled (%d)", request);
736       break;
737   }
738 
739   return false;
740 }
741