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      1 /*
      2 * Copyright (C) 2014 Samsung System LSI
      3 * Copyright (C) 2013 The Android Open Source Project
      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 #define LOG_TAG "bt_btif_sock"
     19 
     20 #include "btif_sock_l2cap.h"
     21 
     22 #include <errno.h>
     23 #include <pthread.h>
     24 #include <stdlib.h>
     25 #include <sys/ioctl.h>
     26 #include <sys/socket.h>
     27 #include <sys/types.h>
     28 #include <unistd.h>
     29 
     30 #include <hardware/bt_sock.h>
     31 
     32 #include "osi/include/allocator.h"
     33 #include "osi/include/log.h"
     34 
     35 #include "bt_target.h"
     36 #include "bta_api.h"
     37 #include "bta_jv_api.h"
     38 #include "bta_jv_co.h"
     39 #include "btif_common.h"
     40 #include "btif_sock_sdp.h"
     41 #include "btif_sock_thread.h"
     42 #include "btif_sock_util.h"
     43 #include "btif_uid.h"
     44 #include "btif_util.h"
     45 #include "btm_api.h"
     46 #include "btm_int.h"
     47 #include "btu.h"
     48 #include "bt_common.h"
     49 #include "hcimsgs.h"
     50 #include "l2c_api.h"
     51 #include "l2cdefs.h"
     52 #include "port_api.h"
     53 #include "sdp_api.h"
     54 
     55 #define asrt(s) if (!(s)) APPL_TRACE_ERROR("## %s assert %s failed at line:%d ##",__FUNCTION__, \
     56         #s, __LINE__)
     57 
     58 struct packet {
     59     struct packet *next, *prev;
     60     uint32_t len;
     61     uint8_t *data;
     62 };
     63 
     64 typedef struct l2cap_socket {
     65 
     66     struct l2cap_socket   *prev;                 //link to prev list item
     67     struct l2cap_socket   *next;                 //link to next list item
     68     bt_bdaddr_t            addr;                 //other side's address
     69     char                   name[256];            //user-friendly name of the service
     70     uint32_t               id;                   //just a tag to find this struct
     71     int                    app_uid;              // The UID of the app who requested this socket
     72     int                    handle;               //handle from lower layers
     73     unsigned               security;             //security flags
     74     int                    channel;              //channel (fixed_chan) or PSM (!fixed_chan)
     75     int                    our_fd;               //fd from our side
     76     int                    app_fd;               //fd from app's side
     77 
     78     unsigned               bytes_buffered;
     79     struct packet         *first_packet;         //fist packet to be delivered to app
     80     struct packet         *last_packet;          //last packet to be delivered to app
     81 
     82     fixed_queue_t         *incoming_que;         //data that came in but has not yet been read
     83     unsigned               fixed_chan       :1;  //fixed channel (or psm?)
     84     unsigned               server           :1;  //is a server? (or connecting?)
     85     unsigned               connected        :1;  //is connected?
     86     unsigned               outgoing_congest :1;  //should we hold?
     87     unsigned               server_psm_sent  :1;  //The server shall only send PSM once.
     88     BOOLEAN                is_le_coc;            //is le connection oriented channel?
     89 } l2cap_socket;
     90 
     91 static bt_status_t btSock_start_l2cap_server_l(l2cap_socket *sock);
     92 
     93 static pthread_mutex_t state_lock;
     94 
     95 l2cap_socket *socks = NULL;
     96 static uid_set_t* uid_set = NULL;
     97 static int pth = -1;
     98 
     99 static void btsock_l2cap_cbk(tBTA_JV_EVT event, tBTA_JV *p_data, void *user_data);
    100 
    101 /* TODO: Consider to remove this buffer, as we have a buffer in l2cap as well, and we risk
    102  *       a buffer overflow with this implementation if the socket data is not read from
    103  *       JAVA for a while. In such a case we should use flow control to tell the sender to
    104  *       back off.
    105  *       BUT remember we need to avoid blocking the BTA task execution - hence we cannot
    106  *       directly write to the socket.
    107  *       we should be able to change to store the data pointer here, and just wait
    108  *       confirming the l2cap_ind until we have more space in the buffer. */
    109 
    110 /* returns FALSE if none - caller must free "data" memory when done with it */
    111 static char packet_get_head_l(l2cap_socket *sock, uint8_t **data, uint32_t *len)
    112 {
    113     struct packet *p = sock->first_packet;
    114 
    115     if (!p)
    116         return FALSE;
    117 
    118     if (data)
    119         *data = sock->first_packet->data;
    120     if (len)
    121         *len = sock->first_packet->len;
    122     sock->first_packet = p->next;
    123     if (sock->first_packet)
    124         sock->first_packet->prev = NULL;
    125     else
    126         sock->last_packet = NULL;
    127 
    128     if(len)
    129         sock->bytes_buffered -= *len;
    130 
    131     osi_free(p);
    132 
    133     return TRUE;
    134 }
    135 
    136 static struct packet *packet_alloc(const uint8_t *data, uint32_t len)
    137 {
    138     struct packet *p = osi_calloc(sizeof(*p));
    139     uint8_t *buf = osi_malloc(len);
    140 
    141     p->data = buf;
    142     p->len = len;
    143     memcpy(p->data, data, len);
    144     return p;
    145 }
    146 
    147 /* makes a copy of the data, returns TRUE on success */
    148 static char packet_put_head_l(l2cap_socket *sock, const void *data, uint32_t len)
    149 {
    150     struct packet *p = packet_alloc((const uint8_t*)data, len);
    151 
    152     /*
    153      * We do not check size limits here since this is used to undo "getting" a
    154      * packet that the user read incompletely. That is to say the packet was
    155      * already in the queue. We do check thos elimits in packet_put_tail_l() since
    156      * that function is used to put new data into the queue.
    157      */
    158 
    159     if (!p)
    160         return FALSE;
    161 
    162     p->prev = NULL;
    163     p->next = sock->first_packet;
    164     sock->first_packet = p;
    165     if (p->next)
    166         p->next->prev = p;
    167     else
    168         sock->last_packet = p;
    169 
    170     sock->bytes_buffered += len;
    171 
    172     return TRUE;
    173 }
    174 
    175 /* makes a copy of the data, returns TRUE on success */
    176 static char packet_put_tail_l(l2cap_socket *sock, const void *data, uint32_t len)
    177 {
    178     struct packet *p = packet_alloc((const uint8_t*)data, len);
    179 
    180     if (sock->bytes_buffered >= L2CAP_MAX_RX_BUFFER) {
    181         LOG_ERROR(LOG_TAG, "packet_put_tail_l: buffer overflow");
    182         return FALSE;
    183     }
    184 
    185     if (!p) {
    186         LOG_ERROR(LOG_TAG, "packet_put_tail_l: unable to allocate packet...");
    187         return FALSE;
    188     }
    189 
    190     p->next = NULL;
    191     p->prev = sock->last_packet;
    192     sock->last_packet = p;
    193     if (p->prev)
    194         p->prev->next = p;
    195     else
    196         sock->first_packet = p;
    197 
    198     sock->bytes_buffered += len;
    199 
    200     return TRUE;
    201 }
    202 
    203 static inline void bd_copy(UINT8* dest, UINT8* src, BOOLEAN swap)
    204 {
    205     if (swap) {
    206         int i;
    207         for (i =0; i < 6 ;i++)
    208             dest[i]= src[5-i];
    209     }
    210     else memcpy(dest, src, 6);
    211 }
    212 
    213 static char is_inited(void)
    214 {
    215     char ret;
    216 
    217     pthread_mutex_lock(&state_lock);
    218     ret = pth != -1;
    219     pthread_mutex_unlock(&state_lock);
    220 
    221     return ret;
    222 }
    223 
    224 /* only call with mutex taken */
    225 static l2cap_socket *btsock_l2cap_find_by_id_l(uint32_t id)
    226 {
    227     l2cap_socket *sock = socks;
    228 
    229     while (sock && sock->id != id)
    230         sock = sock->next;
    231 
    232     return sock;
    233 }
    234 
    235 static void btsock_l2cap_free_l(l2cap_socket *sock)
    236 {
    237     uint8_t *buf;
    238     l2cap_socket *t = socks;
    239 
    240     while(t && t != sock)
    241         t = t->next;
    242 
    243     if (!t) /* prever double-frees */
    244         return;
    245 
    246     if (sock->next)
    247         sock->next->prev = sock->prev;
    248 
    249     if (sock->prev)
    250         sock->prev->next = sock->next;
    251     else
    252         socks = sock->next;
    253 
    254     shutdown(sock->our_fd, SHUT_RDWR);
    255     close(sock->our_fd);
    256     if (sock->app_fd != -1) {
    257         close(sock->app_fd);
    258     } else {
    259         APPL_TRACE_ERROR("SOCK_LIST: free(id = %d) - NO app_fd!", sock->id);
    260     }
    261 
    262     while (packet_get_head_l(sock, &buf, NULL))
    263         osi_free(buf);
    264 
    265     //lower-level close() should be idempotent... so let's call it and see...
    266     if (sock->is_le_coc)
    267     {
    268         // Only call if we are non server connections
    269         if (sock->handle >= 0 && (sock->server == FALSE)) {
    270                 BTA_JvL2capClose(sock->handle);
    271         }
    272         if ((sock->channel >= 0) && (sock->server == TRUE)) {
    273             BTA_JvFreeChannel(sock->channel, BTA_JV_CONN_TYPE_L2CAP);
    274         }
    275     }
    276     else
    277     {
    278         // Only call if we are non server connections
    279         if (sock->handle && (sock->server == FALSE)) {
    280             if (sock->fixed_chan)
    281                 BTA_JvL2capCloseLE(sock->handle);
    282             else
    283                 BTA_JvL2capClose(sock->handle);
    284         }
    285         if ((sock->channel >= 0) && (sock->server == TRUE)) {
    286             if (sock->fixed_chan)
    287                 BTA_JvFreeChannel(sock->channel, BTA_JV_CONN_TYPE_L2CAP_LE);
    288             else
    289                 BTA_JvFreeChannel(sock->channel, BTA_JV_CONN_TYPE_L2CAP);
    290         }
    291     }
    292 
    293     APPL_TRACE_DEBUG("%s: free(id = %d)", __func__, sock->id);
    294     osi_free(sock);
    295 }
    296 
    297 static l2cap_socket *btsock_l2cap_alloc_l(const char *name, const bt_bdaddr_t *addr,
    298         char is_server, int flags)
    299 {
    300     unsigned security = 0;
    301     int fds[2];
    302     l2cap_socket *sock = osi_calloc(sizeof(*sock));
    303 
    304     if (flags & BTSOCK_FLAG_ENCRYPT)
    305         security |= is_server ? BTM_SEC_IN_ENCRYPT : BTM_SEC_OUT_ENCRYPT;
    306     if (flags & BTSOCK_FLAG_AUTH)
    307         security |= is_server ? BTM_SEC_IN_AUTHENTICATE : BTM_SEC_OUT_AUTHENTICATE;
    308     if (flags & BTSOCK_FLAG_AUTH_MITM)
    309         security |= is_server ? BTM_SEC_IN_MITM : BTM_SEC_OUT_MITM;
    310     if (flags & BTSOCK_FLAG_AUTH_16_DIGIT)
    311         security |= BTM_SEC_IN_MIN_16_DIGIT_PIN;
    312 
    313     if (socketpair(AF_LOCAL, SOCK_SEQPACKET, 0, fds)) {
    314         APPL_TRACE_ERROR("socketpair failed, errno:%d", errno);
    315         goto fail_sockpair;
    316     }
    317 
    318     sock->our_fd = fds[0];
    319     sock->app_fd = fds[1];
    320     sock->security = security;
    321     sock->server = is_server;
    322     sock->connected = FALSE;
    323     sock->handle = 0;
    324     sock->server_psm_sent = FALSE;
    325     sock->app_uid = -1;
    326 
    327     if (name)
    328         strncpy(sock->name, name, sizeof(sock->name) - 1);
    329     if (addr)
    330         sock->addr = *addr;
    331 
    332     sock->first_packet = NULL;
    333     sock->last_packet = NULL;
    334 
    335     sock->next = socks;
    336     sock->prev = NULL;
    337     if (socks)
    338         socks->prev = sock;
    339     sock->id = (socks ? socks->id : 0) + 1;
    340     socks = sock;
    341     /* paranoia cap on: verify no ID duplicates due to overflow and fix as needed */
    342     while (1) {
    343         l2cap_socket *t;
    344         t = socks->next;
    345         while (t && t->id != sock->id) {
    346             t = t->next;
    347         }
    348         if (!t && sock->id) /* non-zeor handle is unique -> we're done */
    349             break;
    350         /* if we're here, we found a duplicate */
    351         if (!++sock->id) /* no zero IDs allowed */
    352             sock->id++;
    353     }
    354     APPL_TRACE_DEBUG("SOCK_LIST: alloc(id = %d)", sock->id);
    355     return sock;
    356 
    357 fail_sockpair:
    358     osi_free(sock);
    359     return NULL;
    360 }
    361 
    362 bt_status_t btsock_l2cap_init(int handle, uid_set_t* set)
    363 {
    364     APPL_TRACE_DEBUG("%s handle = %d", __func__);
    365     pthread_mutex_init(&state_lock, NULL);
    366     pthread_mutex_lock(&state_lock);
    367     pth = handle;
    368     socks = NULL;
    369     uid_set = set;
    370     pthread_mutex_unlock(&state_lock);
    371 
    372     return BT_STATUS_SUCCESS;
    373 }
    374 
    375 bt_status_t btsock_l2cap_cleanup()
    376 {
    377     pthread_mutex_lock(&state_lock);
    378     pth = -1;
    379     while (socks)
    380         btsock_l2cap_free_l(socks);
    381     pthread_mutex_unlock(&state_lock);
    382     pthread_mutex_destroy(&state_lock);
    383 
    384     return BT_STATUS_SUCCESS;
    385 }
    386 
    387 static inline BOOLEAN send_app_psm_or_chan_l(l2cap_socket *sock)
    388 {
    389     return sock_send_all(sock->our_fd, (const uint8_t*)&sock->channel, sizeof(sock->channel))
    390             == sizeof(sock->channel);
    391 }
    392 
    393 static BOOLEAN send_app_connect_signal(int fd, const bt_bdaddr_t* addr,
    394         int channel, int status, int send_fd, int tx_mtu)
    395 {
    396     sock_connect_signal_t cs;
    397     cs.size = sizeof(cs);
    398     cs.bd_addr = *addr;
    399     cs.channel = channel;
    400     cs.status = status;
    401     cs.max_rx_packet_size = L2CAP_MAX_SDU_LENGTH;
    402     cs.max_tx_packet_size = tx_mtu;
    403     if (send_fd != -1) {
    404         if (sock_send_fd(fd, (const uint8_t*)&cs, sizeof(cs), send_fd) == sizeof(cs))
    405             return TRUE;
    406         else APPL_TRACE_ERROR("sock_send_fd failed, fd:%d, send_fd:%d", fd, send_fd);
    407     } else if (sock_send_all(fd, (const uint8_t*)&cs, sizeof(cs)) == sizeof(cs)) {
    408         return TRUE;
    409     }
    410     return FALSE;
    411 }
    412 
    413 static void on_srv_l2cap_listen_started(tBTA_JV_L2CAP_START *p_start, uint32_t id)
    414 {
    415     l2cap_socket *sock;
    416 
    417     pthread_mutex_lock(&state_lock);
    418     sock = btsock_l2cap_find_by_id_l(id);
    419     if (sock) {
    420         if (p_start->status != BTA_JV_SUCCESS) {
    421             APPL_TRACE_ERROR("Error starting l2cap_listen - status: 0x%04x", p_start->status);
    422             btsock_l2cap_free_l(sock);
    423         }
    424         else {
    425             sock->handle = p_start->handle;
    426             APPL_TRACE_DEBUG("on_srv_l2cap_listen_started() sock->handle =%d id:%d",
    427                     sock->handle, sock->id);
    428             if(sock->server_psm_sent == FALSE) {
    429                 if (!send_app_psm_or_chan_l(sock)) {
    430                     //closed
    431                     APPL_TRACE_DEBUG("send_app_psm() failed, close rs->id:%d", sock->id);
    432                     btsock_l2cap_free_l(sock);
    433                 } else {
    434                     sock->server_psm_sent = TRUE;
    435                 }
    436             }
    437         }
    438     }
    439     pthread_mutex_unlock(&state_lock);
    440 }
    441 
    442 static void on_cl_l2cap_init(tBTA_JV_L2CAP_CL_INIT *p_init, uint32_t id)
    443 {
    444     l2cap_socket *sock;
    445 
    446     pthread_mutex_lock(&state_lock);
    447     sock = btsock_l2cap_find_by_id_l(id);
    448     if (sock) {
    449         if (p_init->status != BTA_JV_SUCCESS) {
    450             btsock_l2cap_free_l(sock);
    451         } else {
    452             sock->handle = p_init->handle;
    453         }
    454     }
    455     pthread_mutex_unlock(&state_lock);
    456 }
    457 
    458 /**
    459  * Here we allocate a new sock instance to mimic the BluetoothSocket. The socket will be a clone
    460  * of the sock representing the BluetoothServerSocket.
    461  * */
    462 static void on_srv_l2cap_psm_connect_l(tBTA_JV_L2CAP_OPEN *p_open, l2cap_socket *sock)
    463 {
    464     l2cap_socket *accept_rs;
    465     uint32_t new_listen_id;
    466 
    467     // Mutex locked by caller
    468     accept_rs = btsock_l2cap_alloc_l(sock->name, (const bt_bdaddr_t*)p_open->rem_bda, FALSE, 0);
    469     accept_rs->connected = TRUE;
    470     accept_rs->security = sock->security;
    471     accept_rs->fixed_chan = sock->fixed_chan;
    472     accept_rs->channel = sock->channel;
    473     accept_rs->handle = sock->handle;
    474     accept_rs->app_uid = sock->app_uid;
    475     sock->handle = -1; /* We should no longer associate this handle with the server socket */
    476     accept_rs->is_le_coc = sock->is_le_coc;
    477 
    478     /* Swap IDs to hand over the GAP connection to the accepted socket, and start a new server on
    479        the newly create socket ID. */
    480     new_listen_id = accept_rs->id;
    481     accept_rs->id = sock->id;
    482     sock->id = new_listen_id;
    483 
    484     if (accept_rs) {
    485         //start monitor the socket
    486         btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_EXCEPTION, sock->id);
    487         btsock_thread_add_fd(pth, accept_rs->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD,
    488                 accept_rs->id);
    489         APPL_TRACE_DEBUG("sending connect signal & app fd: %d to app server to accept() the"
    490                 " connection", accept_rs->app_fd);
    491         APPL_TRACE_DEBUG("server fd:%d, scn:%d", sock->our_fd, sock->channel);
    492         send_app_connect_signal(sock->our_fd, &accept_rs->addr, sock->channel, 0,
    493                 accept_rs->app_fd, p_open->tx_mtu);
    494         accept_rs->app_fd = -1; // The fd is closed after sent to app in send_app_connect_signal()
    495                                 // But for some reason we still leak a FD - either the server socket
    496                                 // one or the accept socket one.
    497         if(btSock_start_l2cap_server_l(sock) != BT_STATUS_SUCCESS) {
    498             btsock_l2cap_free_l(sock);
    499         }
    500     }
    501 }
    502 
    503 static void on_srv_l2cap_le_connect_l(tBTA_JV_L2CAP_LE_OPEN *p_open, l2cap_socket *sock)
    504 {
    505     l2cap_socket *accept_rs;
    506     uint32_t new_listen_id;
    507 
    508     // mutex locked by caller
    509     accept_rs = btsock_l2cap_alloc_l(sock->name, (const bt_bdaddr_t*)p_open->rem_bda, FALSE, 0);
    510     if (accept_rs) {
    511 
    512         //swap IDs
    513         new_listen_id = accept_rs->id;
    514         accept_rs->id = sock->id;
    515         sock->id = new_listen_id;
    516 
    517         accept_rs->handle = p_open->handle;
    518         accept_rs->connected = TRUE;
    519         accept_rs->security = sock->security;
    520         accept_rs->fixed_chan = sock->fixed_chan;
    521         accept_rs->channel = sock->channel;
    522         accept_rs->app_uid = sock->app_uid;
    523 
    524         //if we do not set a callback, this socket will be dropped */
    525         *(p_open->p_p_cback) = (void*)btsock_l2cap_cbk;
    526         *(p_open->p_user_data) = UINT_TO_PTR(accept_rs->id);
    527 
    528         //start monitor the socket
    529         btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_EXCEPTION, sock->id);
    530         btsock_thread_add_fd(pth, accept_rs->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD,
    531                 accept_rs->id);
    532         APPL_TRACE_DEBUG("sending connect signal & app fd:%dto app server to accept() the"
    533                 " connection", accept_rs->app_fd);
    534         APPL_TRACE_DEBUG("server fd:%d, scn:%d", sock->our_fd, sock->channel);
    535         send_app_connect_signal(sock->our_fd, &accept_rs->addr, sock->channel, 0,
    536                 accept_rs->app_fd, p_open->tx_mtu);
    537         accept_rs->app_fd = -1; //the fd is closed after sent to app
    538     }
    539 }
    540 
    541 static void on_cl_l2cap_psm_connect_l(tBTA_JV_L2CAP_OPEN *p_open, l2cap_socket *sock)
    542 {
    543     bd_copy(sock->addr.address, p_open->rem_bda, 0);
    544 
    545     if (!send_app_psm_or_chan_l(sock)) {
    546         APPL_TRACE_ERROR("send_app_psm_or_chan_l failed");
    547         return;
    548     }
    549 
    550     if (send_app_connect_signal(sock->our_fd, &sock->addr, sock->channel, 0, -1, p_open->tx_mtu)) {
    551         //start monitoring the socketpair to get call back when app writing data
    552         APPL_TRACE_DEBUG("on_l2cap_connect_ind, connect signal sent, slot id:%d, psm:%d,"
    553                 " server:%d", sock->id, sock->channel, sock->server);
    554         btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD, sock->id);
    555         sock->connected = TRUE;
    556     }
    557     else APPL_TRACE_ERROR("send_app_connect_signal failed");
    558 }
    559 
    560 static void on_cl_l2cap_le_connect_l(tBTA_JV_L2CAP_LE_OPEN *p_open, l2cap_socket *sock)
    561 {
    562     bd_copy(sock->addr.address, p_open->rem_bda, 0);
    563 
    564     if (!send_app_psm_or_chan_l(sock)) {
    565         APPL_TRACE_ERROR("send_app_psm_or_chan_l failed");
    566         return;
    567     }
    568 
    569     if (send_app_connect_signal(sock->our_fd, &sock->addr, sock->channel, 0, -1, p_open->tx_mtu)) {
    570         //start monitoring the socketpair to get call back when app writing data
    571         APPL_TRACE_DEBUG("on_l2cap_connect_ind, connect signal sent, slot id:%d, Chan:%d,"
    572                 " server:%d", sock->id, sock->channel, sock->server);
    573         btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD, sock->id);
    574         sock->connected = TRUE;
    575     }
    576     else APPL_TRACE_ERROR("send_app_connect_signal failed");
    577 }
    578 
    579 static void on_l2cap_connect(tBTA_JV *p_data, uint32_t id)
    580 {
    581     l2cap_socket *sock;
    582     tBTA_JV_L2CAP_OPEN *psm_open = &p_data->l2c_open;
    583     tBTA_JV_L2CAP_LE_OPEN *le_open = &p_data->l2c_le_open;
    584 
    585     pthread_mutex_lock(&state_lock);
    586     sock = btsock_l2cap_find_by_id_l(id);
    587     if (!sock) {
    588         APPL_TRACE_ERROR("on_l2cap_connect on unknown socket");
    589     } else {
    590         if (sock->fixed_chan && le_open->status == BTA_JV_SUCCESS) {
    591             if (!sock->server)
    592                 on_cl_l2cap_le_connect_l(le_open, sock);
    593             else
    594                 on_srv_l2cap_le_connect_l(le_open, sock);
    595         } else if (!sock->fixed_chan && psm_open->status == BTA_JV_SUCCESS) {
    596             if (!sock->server)
    597                 on_cl_l2cap_psm_connect_l(psm_open, sock);
    598             else
    599                 on_srv_l2cap_psm_connect_l(psm_open, sock);
    600         }
    601         else
    602             btsock_l2cap_free_l(sock);
    603     }
    604     pthread_mutex_unlock(&state_lock);
    605 }
    606 
    607 static void on_l2cap_close(tBTA_JV_L2CAP_CLOSE * p_close, uint32_t id)
    608 {
    609     l2cap_socket *sock;
    610 
    611     pthread_mutex_lock(&state_lock);
    612     sock = btsock_l2cap_find_by_id_l(id);
    613     if (sock) {
    614         APPL_TRACE_DEBUG("on_l2cap_close, slot id:%d, fd:%d, %s:%d, server:%d",
    615                 sock->id, sock->our_fd, sock->fixed_chan ? "fixed_chan" : "PSM",
    616                 sock->channel, sock->server);
    617         // TODO: This does not seem to be called...
    618         // I'm not sure if this will be called for non-server sockets?
    619         if(!sock->fixed_chan && (sock->server == TRUE)) {
    620             BTA_JvFreeChannel(sock->channel, BTA_JV_CONN_TYPE_L2CAP);
    621         }
    622         btsock_l2cap_free_l(sock);
    623     }
    624     pthread_mutex_unlock(&state_lock);
    625 }
    626 
    627 static void on_l2cap_outgoing_congest(tBTA_JV_L2CAP_CONG *p, uint32_t id)
    628 {
    629     l2cap_socket *sock;
    630 
    631     pthread_mutex_lock(&state_lock);
    632     sock = btsock_l2cap_find_by_id_l(id);
    633     if (sock) {
    634         sock->outgoing_congest = p->cong ? 1 : 0;
    635         //mointer the fd for any outgoing data
    636         if (!sock->outgoing_congest) {
    637             APPL_TRACE_DEBUG("on_l2cap_outgoing_congest: adding fd to btsock_thread...");
    638             btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD, sock->id);
    639 
    640         }
    641     }
    642     pthread_mutex_unlock(&state_lock);
    643 }
    644 
    645 static void on_l2cap_write_done(void* req_id, uint16_t len, uint32_t id)
    646 {
    647     l2cap_socket *sock;
    648 
    649     if (req_id != NULL) {
    650         osi_free(req_id); //free the buffer
    651     }
    652 
    653     int app_uid = -1;
    654 
    655     pthread_mutex_lock(&state_lock);
    656     sock = btsock_l2cap_find_by_id_l(id);
    657     if (sock) {
    658         app_uid = sock->app_uid;
    659         if (!sock->outgoing_congest) {
    660             //monitor the fd for any outgoing data
    661             APPL_TRACE_DEBUG("on_l2cap_write_done: adding fd to btsock_thread...");
    662             btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD, sock->id);
    663         }
    664     }
    665     pthread_mutex_unlock(&state_lock);
    666 
    667     uid_set_add_tx(uid_set, app_uid, len);
    668 }
    669 
    670 static void on_l2cap_write_fixed_done(void* req_id, uint16_t len, uint32_t id)
    671 {
    672     l2cap_socket *sock;
    673 
    674     if (req_id != NULL) {
    675         osi_free(req_id); //free the buffer
    676     }
    677 
    678     int app_uid = -1;
    679     pthread_mutex_lock(&state_lock);
    680     sock = btsock_l2cap_find_by_id_l(id);
    681     if (sock) {
    682         app_uid = sock->app_uid;
    683         if (!sock->outgoing_congest) {
    684             //monitor the fd for any outgoing data
    685             btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_RD, sock->id);
    686         }
    687     }
    688     pthread_mutex_unlock(&state_lock);
    689 
    690     uid_set_add_tx(uid_set, app_uid, len);
    691 }
    692 
    693 static void on_l2cap_data_ind(tBTA_JV *evt, uint32_t id)
    694 {
    695     l2cap_socket *sock;
    696 
    697     int app_uid = -1;
    698     UINT32 bytes_read = 0;
    699 
    700     pthread_mutex_lock(&state_lock);
    701     sock = btsock_l2cap_find_by_id_l(id);
    702     if (sock) {
    703         app_uid = sock->app_uid;
    704 
    705         if (sock->fixed_chan) { /* we do these differently */
    706 
    707             tBTA_JV_LE_DATA_IND *p_le_data_ind = &evt->le_data_ind;
    708             BT_HDR *p_buf = p_le_data_ind->p_buf;
    709             uint8_t *data = (uint8_t*)(p_buf + 1) + p_buf->offset;
    710 
    711             if (packet_put_tail_l(sock, data, p_buf->len)) {
    712                 bytes_read = p_buf->len;
    713                 btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_WR, sock->id);
    714             } else {//connection must be dropped
    715                 APPL_TRACE_DEBUG("on_l2cap_data_ind() unable to push data to socket - closing"
    716                         " fixed channel");
    717                 BTA_JvL2capCloseLE(sock->handle);
    718                 btsock_l2cap_free_l(sock);
    719             }
    720 
    721         } else {
    722 
    723             UINT8 buffer[L2CAP_MAX_SDU_LENGTH];
    724             UINT32  count;
    725 
    726             if (BTA_JvL2capReady(sock->handle, &count) == BTA_JV_SUCCESS) {
    727                 if (BTA_JvL2capRead(sock->handle, sock->id, buffer, count) == BTA_JV_SUCCESS) {
    728                     if (packet_put_tail_l(sock, buffer, count)) {
    729                         bytes_read = count;
    730                         btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_WR,
    731                                 sock->id);
    732                     } else {//connection must be dropped
    733                         APPL_TRACE_DEBUG("on_l2cap_data_ind() unable to push data to socket"
    734                                 " - closing channel");
    735                         BTA_JvL2capClose(sock->handle);
    736                         btsock_l2cap_free_l(sock);
    737                     }
    738                 }
    739             }
    740         }
    741     }
    742     pthread_mutex_unlock(&state_lock);
    743 
    744     uid_set_add_rx(uid_set, app_uid, bytes_read);
    745 }
    746 
    747 static void btsock_l2cap_cbk(tBTA_JV_EVT event, tBTA_JV *p_data, void *user_data)
    748 {
    749     uint32_t sock_id = PTR_TO_UINT(user_data);
    750 
    751     switch (event) {
    752     case BTA_JV_L2CAP_START_EVT:
    753         on_srv_l2cap_listen_started(&p_data->l2c_start, sock_id);
    754         break;
    755 
    756     case BTA_JV_L2CAP_CL_INIT_EVT:
    757         on_cl_l2cap_init(&p_data->l2c_cl_init, sock_id);
    758         break;
    759 
    760     case BTA_JV_L2CAP_OPEN_EVT:
    761         on_l2cap_connect(p_data, sock_id);
    762         BTA_JvSetPmProfile(p_data->l2c_open.handle, BTA_JV_PM_ID_1,BTA_JV_CONN_OPEN);
    763         break;
    764 
    765     case BTA_JV_L2CAP_CLOSE_EVT:
    766         APPL_TRACE_DEBUG("BTA_JV_L2CAP_CLOSE_EVT: id: %u", sock_id);
    767         on_l2cap_close(&p_data->l2c_close, sock_id);
    768         break;
    769 
    770     case BTA_JV_L2CAP_DATA_IND_EVT:
    771         on_l2cap_data_ind(p_data, sock_id);
    772         APPL_TRACE_DEBUG("BTA_JV_L2CAP_DATA_IND_EVT");
    773         break;
    774 
    775     case BTA_JV_L2CAP_READ_EVT:
    776         APPL_TRACE_DEBUG("BTA_JV_L2CAP_READ_EVT not used");
    777         break;
    778 
    779     case BTA_JV_L2CAP_WRITE_EVT:
    780         APPL_TRACE_DEBUG("BTA_JV_L2CAP_WRITE_EVT: id: %u", sock_id);
    781         on_l2cap_write_done(UINT_TO_PTR(p_data->l2c_write.req_id), p_data->l2c_write.len, sock_id);
    782         break;
    783 
    784     case BTA_JV_L2CAP_WRITE_FIXED_EVT:
    785         APPL_TRACE_DEBUG("BTA_JV_L2CAP_WRITE_FIXED_EVT: id: %u", sock_id);
    786         on_l2cap_write_fixed_done(UINT_TO_PTR(p_data->l2c_write_fixed.req_id), p_data->l2c_write.len, sock_id);
    787         break;
    788 
    789     case BTA_JV_L2CAP_CONG_EVT:
    790         on_l2cap_outgoing_congest(&p_data->l2c_cong, sock_id);
    791         break;
    792 
    793     default:
    794         APPL_TRACE_ERROR("unhandled event %d, slot id: %u", event, sock_id);
    795         break;
    796     }
    797 }
    798 
    799 /* L2CAP default options for OBEX socket connections */
    800 const tL2CAP_FCR_OPTS obex_l2c_fcr_opts_def =
    801 {
    802     L2CAP_FCR_ERTM_MODE,            /* Mandatory for OBEX over l2cap */
    803     OBX_FCR_OPT_TX_WINDOW_SIZE_BR_EDR,/* Tx window size */
    804     OBX_FCR_OPT_MAX_TX_B4_DISCNT,   /* Maximum transmissions before disconnecting */
    805     OBX_FCR_OPT_RETX_TOUT,          /* Retransmission timeout (2 secs) */
    806     OBX_FCR_OPT_MONITOR_TOUT,       /* Monitor timeout (12 secs) */
    807     OBX_FCR_OPT_MAX_PDU_SIZE        /* MPS segment size */
    808 };
    809 const tL2CAP_ERTM_INFO obex_l2c_etm_opt =
    810 {
    811         L2CAP_FCR_ERTM_MODE,            /* Mandatory for OBEX over l2cap */
    812         L2CAP_FCR_CHAN_OPT_ERTM,        /* Mandatory for OBEX over l2cap */
    813         OBX_USER_RX_BUF_SIZE,
    814         OBX_USER_TX_BUF_SIZE,
    815         OBX_FCR_RX_BUF_SIZE,
    816         OBX_FCR_TX_BUF_SIZE
    817 };
    818 
    819 /**
    820  * When using a dynamic PSM, a PSM allocation is requested from btsock_l2cap_listen_or_connect().
    821  * The PSM allocation event is refeived in the JV-callback - currently located in RFC-code -
    822  * and this function is called with the newly allocated PSM.
    823  */
    824 void on_l2cap_psm_assigned(int id, int psm) {
    825     l2cap_socket *sock;
    826     /* Setup ETM settings:
    827      *  mtu will be set below */
    828     pthread_mutex_lock(&state_lock);
    829     sock = btsock_l2cap_find_by_id_l(id);
    830     sock->channel = psm;
    831 
    832     if(btSock_start_l2cap_server_l(sock) != BT_STATUS_SUCCESS) {
    833         btsock_l2cap_free_l(sock);
    834     }
    835 
    836     pthread_mutex_unlock(&state_lock);
    837 
    838 }
    839 
    840 static bt_status_t btSock_start_l2cap_server_l(l2cap_socket *sock) {
    841     tL2CAP_CFG_INFO cfg;
    842     bt_status_t stat = BT_STATUS_SUCCESS;
    843     /* Setup ETM settings:
    844      *  mtu will be set below */
    845     memset(&cfg, 0, sizeof(tL2CAP_CFG_INFO));
    846 
    847     cfg.fcr_present = TRUE;
    848     cfg.fcr = obex_l2c_fcr_opts_def;
    849 
    850     if (sock->fixed_chan) {
    851 
    852         if (BTA_JvL2capStartServerLE(sock->security, 0, NULL, sock->channel,
    853                 L2CAP_DEFAULT_MTU, NULL, btsock_l2cap_cbk, UINT_TO_PTR(sock->id))
    854                 != BTA_JV_SUCCESS)
    855             stat = BT_STATUS_FAIL;
    856 
    857     } else {
    858         /* If we have a channel specified in the request, just start the server,
    859          * else we request a PSM and start the server after we receive a PSM. */
    860         if (sock->channel < 0) {
    861             if (sock->is_le_coc) {
    862                 if (BTA_JvGetChannelId(BTA_JV_CONN_TYPE_L2CAP_LE, UINT_TO_PTR(sock->id), 0)
    863                         != BTA_JV_SUCCESS)
    864                     stat = BT_STATUS_FAIL;
    865             }
    866             else
    867             {
    868                 if (BTA_JvGetChannelId(BTA_JV_CONN_TYPE_L2CAP, UINT_TO_PTR(sock->id), 0)
    869                         != BTA_JV_SUCCESS)
    870                     stat = BT_STATUS_FAIL;
    871             }
    872         } else {
    873             if (sock->is_le_coc) {
    874                 if (BTA_JvL2capStartServer(BTA_JV_CONN_TYPE_L2CAP_LE, sock->security, 0, NULL,
    875                         sock->channel, L2CAP_MAX_SDU_LENGTH, &cfg, btsock_l2cap_cbk, UINT_TO_PTR(sock->id))
    876                         != BTA_JV_SUCCESS)
    877                     stat = BT_STATUS_FAIL;
    878             }
    879             else
    880             {
    881                 if (BTA_JvL2capStartServer(BTA_JV_CONN_TYPE_L2CAP, sock->security, 0, &obex_l2c_etm_opt,
    882                         sock->channel, L2CAP_MAX_SDU_LENGTH, &cfg, btsock_l2cap_cbk, UINT_TO_PTR(sock->id))
    883                         != BTA_JV_SUCCESS)
    884                     stat = BT_STATUS_FAIL;
    885             }
    886         }
    887     }
    888     return stat;
    889 }
    890 
    891 static bt_status_t btsock_l2cap_listen_or_connect(const char *name, const bt_bdaddr_t *addr,
    892         int channel, int* sock_fd, int flags, char listen, int app_uid)
    893 {
    894     bt_status_t stat;
    895     int fixed_chan = 1;
    896     l2cap_socket *sock;
    897     tL2CAP_CFG_INFO cfg;
    898     BOOLEAN is_le_coc = FALSE;
    899 
    900     if (!sock_fd)
    901         return BT_STATUS_PARM_INVALID;
    902 
    903     if(channel < 0) {
    904         // We need to auto assign a PSM
    905         fixed_chan = 0;
    906     } else {
    907         fixed_chan = (channel & L2CAP_MASK_FIXED_CHANNEL) != 0;
    908         is_le_coc = (channel & L2CAP_MASK_LE_COC_CHANNEL) != 0;
    909         channel &=~ (L2CAP_MASK_FIXED_CHANNEL | L2CAP_MASK_LE_COC_CHANNEL);
    910     }
    911 
    912     if (!is_inited())
    913         return BT_STATUS_NOT_READY;
    914 
    915     // TODO: This is kind of bad to lock here, but it is needed for the current design.
    916     pthread_mutex_lock(&state_lock);
    917 
    918     sock = btsock_l2cap_alloc_l(name, addr, listen, flags);
    919     if (!sock) {
    920         pthread_mutex_unlock(&state_lock);
    921         return BT_STATUS_NOMEM;
    922     }
    923 
    924     sock->fixed_chan = fixed_chan;
    925     sock->channel = channel;
    926     sock->app_uid = app_uid;
    927     sock->is_le_coc = is_le_coc;
    928 
    929     stat = BT_STATUS_SUCCESS;
    930 
    931     /* Setup ETM settings:
    932      *  mtu will be set below */
    933     memset(&cfg, 0, sizeof(tL2CAP_CFG_INFO));
    934 
    935     cfg.fcr_present = TRUE;
    936     cfg.fcr = obex_l2c_fcr_opts_def;
    937 
    938     /* "role" is never initialized in rfcomm code */
    939     if (listen) {
    940         stat = btSock_start_l2cap_server_l(sock);
    941     } else {
    942         if (fixed_chan) {
    943             if (BTA_JvL2capConnectLE(sock->security, 0, NULL, channel,
    944                     L2CAP_DEFAULT_MTU, NULL, sock->addr.address, btsock_l2cap_cbk,
    945                     UINT_TO_PTR(sock->id)) != BTA_JV_SUCCESS)
    946                 stat = BT_STATUS_FAIL;
    947 
    948         } else {
    949             if (sock->is_le_coc) {
    950                 if (BTA_JvL2capConnect(BTA_JV_CONN_TYPE_L2CAP_LE, sock->security, 0, NULL,
    951                         channel, L2CAP_MAX_SDU_LENGTH, &cfg, sock->addr.address,
    952                         btsock_l2cap_cbk, UINT_TO_PTR(sock->id)) != BTA_JV_SUCCESS)
    953                     stat = BT_STATUS_FAIL;
    954             }
    955             else
    956             {
    957                 if (BTA_JvL2capConnect(BTA_JV_CONN_TYPE_L2CAP, sock->security, 0, &obex_l2c_etm_opt,
    958                         channel, L2CAP_MAX_SDU_LENGTH, &cfg, sock->addr.address,
    959                         btsock_l2cap_cbk, UINT_TO_PTR(sock->id)) != BTA_JV_SUCCESS)
    960                     stat = BT_STATUS_FAIL;
    961             }
    962         }
    963     }
    964 
    965     if (stat == BT_STATUS_SUCCESS) {
    966         *sock_fd = sock->app_fd;
    967         /* We pass the FD to JAVA, but since it runs in another process, we need to also close
    968          * it in native, either straight away, as done when accepting an incoming connection,
    969          * or when doing cleanup after this socket */
    970         sock->app_fd = -1;  /*This leaks the file descriptor. The FD should be closed in
    971                               JAVA but it apparently do not work */
    972         btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_EXCEPTION,
    973                 sock->id);
    974     } else {
    975        btsock_l2cap_free_l(sock);
    976     }
    977     pthread_mutex_unlock(&state_lock);
    978 
    979     return stat;
    980 }
    981 
    982 bt_status_t btsock_l2cap_listen(const char* name, int channel, int* sock_fd, int flags, int app_uid)
    983 {
    984     return btsock_l2cap_listen_or_connect(name, NULL, channel, sock_fd, flags, 1, app_uid);
    985 }
    986 
    987 bt_status_t btsock_l2cap_connect(const bt_bdaddr_t *bd_addr, int channel, int* sock_fd, int flags, int app_uid)
    988 {
    989     return btsock_l2cap_listen_or_connect(NULL, bd_addr, channel, sock_fd, flags, 0, app_uid);
    990 }
    991 
    992 /* return TRUE if we have more to send and should wait for user readiness, FALSE else
    993  * (for example: unrecoverable error or no data)
    994  */
    995 static BOOLEAN flush_incoming_que_on_wr_signal_l(l2cap_socket *sock)
    996 {
    997     uint8_t *buf;
    998     uint32_t len;
    999 
   1000     while (packet_get_head_l(sock, &buf, &len)) {
   1001         ssize_t sent;
   1002         OSI_NO_INTR(sent = send(sock->our_fd, buf, len, MSG_DONTWAIT));
   1003         int saved_errno = errno;
   1004 
   1005         if (sent == (signed)len)
   1006             osi_free(buf);
   1007         else if (sent >= 0) {
   1008             packet_put_head_l(sock, buf + sent, len - sent);
   1009             osi_free(buf);
   1010             if (!sent) /* special case if other end not keeping up */
   1011                 return TRUE;
   1012         }
   1013         else {
   1014             packet_put_head_l(sock, buf, len);
   1015             osi_free(buf);
   1016             return saved_errno == EWOULDBLOCK || saved_errno == EAGAIN;
   1017         }
   1018     }
   1019 
   1020     return FALSE;
   1021 }
   1022 
   1023 void btsock_l2cap_signaled(int fd, int flags, uint32_t user_id)
   1024 {
   1025     l2cap_socket *sock;
   1026     char drop_it = FALSE;
   1027 
   1028     /* We use MSG_DONTWAIT when sending data to JAVA, hence it can be accepted to hold the lock. */
   1029     pthread_mutex_lock(&state_lock);
   1030     sock = btsock_l2cap_find_by_id_l(user_id);
   1031     if (sock) {
   1032         if ((flags & SOCK_THREAD_FD_RD) && !sock->server) {
   1033             //app sending data
   1034             if (sock->connected) {
   1035                 int size = 0;
   1036 
   1037                 if (!(flags & SOCK_THREAD_FD_EXCEPTION) || (ioctl(sock->our_fd, FIONREAD, &size)
   1038                         == 0 && size)) {
   1039                     uint8_t *buffer = osi_malloc(L2CAP_MAX_SDU_LENGTH);
   1040                     /* Apparently we hijack the req_id (UINT32) to pass the pointer to the buffer to
   1041                      * the write complete callback, which call a free... wonder if this works on a
   1042                      * 64 bit platform? */
   1043                     /* The socket is created with SOCK_SEQPACKET, hence we read one message at
   1044                      * the time. The maximum size of a message is allocated to ensure data is
   1045                      * not lost. This is okay to do as Android uses virtual memory, hence even
   1046                      * if we only use a fraction of the memory it should not block for others
   1047                      * to use the memory. As the definition of ioctl(FIONREAD) do not clearly
   1048                      * define what value will be returned if multiple messages are written to
   1049                      * the socket before any message is read from the socket, we could
   1050                      * potentially risk to allocate way more memory than needed. One of the use
   1051                      * cases for this socket is obex where multiple 64kbyte messages are
   1052                      * typically written to the socket in a tight loop, hence we risk the ioctl
   1053                      * will return the total amount of data in the buffer, which could be
   1054                      * multiple 64kbyte chunks.
   1055                      * UPDATE: As the stack cannot handle 64kbyte buffers, the size is reduced
   1056                      * to around 8kbyte - and using malloc for buffer allocation here seems to
   1057                      * be wrong
   1058                      * UPDATE: Since we are responsible for freeing the buffer in the
   1059                      * write_complete_ind, it is OK to use malloc. */
   1060                     ssize_t count;
   1061                     OSI_NO_INTR(count = recv(fd, buffer, L2CAP_MAX_SDU_LENGTH,
   1062                                              MSG_NOSIGNAL | MSG_DONTWAIT));
   1063                     APPL_TRACE_DEBUG("btsock_l2cap_signaled - %d bytes received from socket",
   1064                                      count);
   1065 
   1066                     // TODO(armansito): |buffer|, which is created above via
   1067                     // malloc, is being cast below to UINT32 to be used as
   1068                     // the |req_id| parameter of BTA_JvL2capWriteFixed and
   1069                     // BTA_JvL2capWrite. The "id" then gets freed in an
   1070                     // obscure callback elsewhere. We need to watch out for
   1071                     // this type of unsafe practice, as this is error prone
   1072                     // and difficult to follow.
   1073                     if (sock->fixed_chan) {
   1074                         if (BTA_JvL2capWriteFixed(sock->channel,
   1075                                                   (BD_ADDR*)&sock->addr,
   1076                                                   PTR_TO_UINT(buffer),
   1077                                                   btsock_l2cap_cbk, buffer,
   1078                                                   count,
   1079                                                   UINT_TO_PTR(user_id)) != BTA_JV_SUCCESS) {
   1080                             // On fail, free the buffer
   1081                             on_l2cap_write_fixed_done(buffer, count, user_id);
   1082                         }
   1083                     } else {
   1084                         if (BTA_JvL2capWrite(sock->handle, PTR_TO_UINT(buffer),
   1085                                              buffer, count,
   1086                                              UINT_TO_PTR(user_id)) != BTA_JV_SUCCESS) {
   1087                           // On fail, free the buffer
   1088                           on_l2cap_write_done(buffer, count, user_id);
   1089                         }
   1090                     }
   1091                 }
   1092             } else
   1093                 drop_it = TRUE;
   1094         }
   1095         if (flags & SOCK_THREAD_FD_WR) {
   1096             //app is ready to receive more data, tell stack to enable the data flow
   1097             if (flush_incoming_que_on_wr_signal_l(sock) && sock->connected)
   1098                 btsock_thread_add_fd(pth, sock->our_fd, BTSOCK_L2CAP, SOCK_THREAD_FD_WR, sock->id);
   1099         }
   1100         if (drop_it || (flags & SOCK_THREAD_FD_EXCEPTION)) {
   1101             int size = 0;
   1102             if (drop_it || ioctl(sock->our_fd, FIONREAD, &size) != 0 || size == 0)
   1103                 btsock_l2cap_free_l(sock);
   1104         }
   1105     }
   1106     pthread_mutex_unlock(&state_lock);
   1107 }
   1108 
   1109