esp-idf/components/bt/bluedroid/stack/gatt/gatt_utils.c

/******************************************************************************
 *
 *  Copyright (C) 2009-2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  this file contains GATT utility functions
 *
 ******************************************************************************/
#include "bt_target.h"
#include "allocator.h"

#if BLE_INCLUDED == TRUE
#include <string.h>
#include <stdio.h>

#include "l2cdefs.h"
#include "gatt_int.h"
#include "gatt_api.h"
#include "gattdefs.h"
#include "sdp_api.h"
#include "btm_int.h"
/* check if [x, y] and [a, b] have overlapping range */
#define GATT_VALIDATE_HANDLE_RANGE(x, y, a, b)   (y >= a && x <= b)

#define GATT_GET_NEXT_VALID_HANDLE(x)    (((x)/10 + 1) * 10)

const char *const op_code_name[] = {
    "UNKNOWN",
    "ATT_RSP_ERROR",
    "ATT_REQ_MTU",
    "ATT_RSP_MTU",
    "ATT_REQ_READ_INFO",
    "ATT_RSP_READ_INFO",
    "ATT_REQ_FIND_TYPE_VALUE",
    "ATT_RSP_FIND_TYPE_VALUE",
    "ATT_REQ_READ_BY_TYPE",
    "ATT_RSP_READ_BY_TYPE",
    "ATT_REQ_READ",
    "ATT_RSP_READ",
    "ATT_REQ_READ_BLOB",
    "ATT_RSP_READ_BLOB",
    "GATT_REQ_READ_MULTI",
    "GATT_RSP_READ_MULTI",
    "GATT_REQ_READ_BY_GRP_TYPE",
    "GATT_RSP_READ_BY_GRP_TYPE",
    "ATT_REQ_WRITE",
    "ATT_RSP_WRITE",
    "ATT_CMD_WRITE",
    "ATT_SIGN_CMD_WRITE",
    "ATT_REQ_PREPARE_WRITE",
    "ATT_RSP_PREPARE_WRITE",
    "ATT_REQ_EXEC_WRITE",
    "ATT_RSP_EXEC_WRITE",
    "Reserved",
    "ATT_HANDLE_VALUE_NOTIF",
    "Reserved",
    "ATT_HANDLE_VALUE_IND",
    "ATT_HANDLE_VALUE_CONF",
    "ATT_OP_CODE_MAX"
};

static const UINT8  base_uuid[LEN_UUID_128] = {0xFB, 0x34, 0x9B, 0x5F, 0x80, 0x00, 0x00, 0x80,
                                               0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
                                              };


/*******************************************************************************
**
** Function         gatt_free_pending_ind
**
** Description    Free all pending indications
**
** Returns       None
**
*******************************************************************************/
void gatt_free_pending_ind(tGATT_TCB *p_tcb)
{
    GATT_TRACE_DEBUG("gatt_free_pending_ind");
    if (p_tcb->pending_ind_q == NULL) {
        return;
    }
	
    /* release all queued indications */
    while (!fixed_queue_is_empty(p_tcb->pending_ind_q)) {
        osi_free(fixed_queue_try_dequeue(p_tcb->pending_ind_q));
	}
    fixed_queue_free(p_tcb->pending_ind_q, NULL);
    p_tcb->pending_ind_q = NULL;
}

/*******************************************************************************
**
** Function         gatt_free_pending_enc_queue
**
** Description       Free all buffers in pending encyption queue
**
** Returns       None
**
*******************************************************************************/
void gatt_free_pending_enc_queue(tGATT_TCB *p_tcb)
{
    GATT_TRACE_DEBUG("gatt_free_pending_enc_queue");
    if (p_tcb->pending_enc_clcb == NULL) {
        return;
    }
	
    /* release all queued indications */
    while (!fixed_queue_is_empty(p_tcb->pending_enc_clcb)) {
        osi_free(fixed_queue_try_dequeue(p_tcb->pending_enc_clcb));
    }
	fixed_queue_free(p_tcb->pending_enc_clcb, NULL);
    p_tcb->pending_enc_clcb = NULL;
}

/*******************************************************************************
**
** Function         gatt_free_pending_prepare_write_queue
**
** Description       Free all buffers in pending prepare write packets queue
**
** Returns       None
**
*******************************************************************************/
void gatt_free_pending_prepare_write_queue(tGATT_TCB *p_tcb)
{
    GATT_TRACE_DEBUG("gatt_free_pending_prepare_write_queue");

    if (p_tcb->prepare_write_record.queue) {
        /* release all queued prepare write packets */
        while (!fixed_queue_is_empty(p_tcb->prepare_write_record.queue)) {
            osi_free(fixed_queue_dequeue(p_tcb->prepare_write_record.queue));
        }
        fixed_queue_free(p_tcb->prepare_write_record.queue, NULL);
        p_tcb->prepare_write_record.queue = NULL;
    }

    p_tcb->prepare_write_record.total_num = 0;
    p_tcb->prepare_write_record.error_code_app = GATT_SUCCESS;
}

/*******************************************************************************
**
** Function         gatt_delete_dev_from_srv_chg_clt_list
**
** Description    Delete a device from the service changed client lit
**
** Returns       None
**
*******************************************************************************/
void gatt_delete_dev_from_srv_chg_clt_list(BD_ADDR bd_addr)
{
    tGATTS_SRV_CHG     *p_buf;
    tGATTS_SRV_CHG_REQ  req;

    GATT_TRACE_DEBUG ("gatt_delete_dev_from_srv_chg_clt_list");
    if ((p_buf = gatt_is_bda_in_the_srv_chg_clt_list(bd_addr)) != NULL) {
        if (gatt_cb.cb_info.p_srv_chg_callback) {
            /* delete from NV */
            memcpy(req.srv_chg.bda, bd_addr, BD_ADDR_LEN);
            (*gatt_cb.cb_info.p_srv_chg_callback)(GATTS_SRV_CHG_CMD_REMOVE_CLIENT, &req, NULL);
        }
        osi_free(fixed_queue_try_remove_from_queue(gatt_cb.srv_chg_clt_q,
                                                      p_buf));
    }

}

/*******************************************************************************
**
** Function         gatt_set_srv_chg
**
** Description      Set the service changed flag to TRUE
**
** Returns        None
**
*******************************************************************************/
void gatt_set_srv_chg(void)
{
    GATT_TRACE_DEBUG ("gatt_set_srv_chg");

    if (fixed_queue_is_empty(gatt_cb.srv_chg_clt_q)) {
        return;
	}

    list_t *list = fixed_queue_get_list(gatt_cb.srv_chg_clt_q);
    for (const list_node_t *node = list_begin(list); node != list_end(list);
         node = list_next(node)) {
        GATT_TRACE_DEBUG ("found a srv_chg clt");

        tGATTS_SRV_CHG *p_buf = (tGATTS_SRV_CHG *)list_node(node);
        if (!p_buf->srv_changed) {
            GATT_TRACE_DEBUG("set srv_changed to TRUE");
            p_buf->srv_changed = TRUE;
            tGATTS_SRV_CHG_REQ req;
            memcpy(&req.srv_chg, p_buf, sizeof(tGATTS_SRV_CHG));
            if (gatt_cb.cb_info.p_srv_chg_callback) {
                (*gatt_cb.cb_info.p_srv_chg_callback)(GATTS_SRV_CHG_CMD_UPDATE_CLIENT,&req, NULL);
			}
        }
    }
}

/*******************************************************************************
**
** Function         gatt_sr_is_new_srv_chg
**
** Description     Find the app id in on the new service changed list
**
** Returns     Pointer to the found new service changed item othwerwise NULL
**
*******************************************************************************/
tGATTS_PENDING_NEW_SRV_START *gatt_sr_is_new_srv_chg(tBT_UUID *p_app_uuid128, tBT_UUID *p_svc_uuid, UINT16 svc_inst)
{
    tGATTS_PENDING_NEW_SRV_START *p_buf = NULL;

    if (fixed_queue_is_empty(gatt_cb.pending_new_srv_start_q)) {
        return NULL;
	}

    list_t *list = fixed_queue_get_list(gatt_cb.pending_new_srv_start_q);
    for (const list_node_t *node = list_begin(list); node != list_end(list);
         node = list_next(node)) {
        p_buf = (tGATTS_PENDING_NEW_SRV_START *)list_node(node);
        tGATTS_HNDL_RANGE *p = p_buf->p_new_srv_start;
        if (gatt_uuid_compare(*p_app_uuid128, p->app_uuid128)
            && gatt_uuid_compare (*p_svc_uuid, p->svc_uuid)
            && (svc_inst == p->svc_inst)) {
            GATT_TRACE_DEBUG("gatt_sr_is_new_srv_chg: Yes");
            break;
        }
    }

    return p_buf;
}


/*******************************************************************************
**
** Function     gatt_add_pending_ind
**
** Description  Add a pending indication
**
** Returns    Pointer to the current pending indication buffer, NULL no buffer available
**
*******************************************************************************/
tGATT_VALUE *gatt_add_pending_ind(tGATT_TCB  *p_tcb, tGATT_VALUE *p_ind)
{
    tGATT_VALUE   *p_buf;
    GATT_TRACE_DEBUG ("gatt_add_pending_ind");
    if ((p_buf = (tGATT_VALUE *)osi_malloc((UINT16)sizeof(tGATT_VALUE))) != NULL) {
        GATT_TRACE_DEBUG ("enqueue a pending indication");
        memcpy(p_buf, p_ind, sizeof(tGATT_VALUE));
    fixed_queue_enqueue(p_tcb->pending_ind_q, p_buf);
    }
    return p_buf;
}


/*******************************************************************************
**
** Function     gatt_add_pending_new_srv_start
**
** Description  Add a pending new srv start to the new service start queue
**
** Returns    Pointer to the new service start buffer, NULL no buffer available
**
*******************************************************************************/
tGATTS_PENDING_NEW_SRV_START *gatt_add_pending_new_srv_start(tGATTS_HNDL_RANGE *p_new_srv_start)
{
    tGATTS_PENDING_NEW_SRV_START   *p_buf;

    GATT_TRACE_DEBUG ("gatt_add_pending_new_srv_start");
    if ((p_buf = (tGATTS_PENDING_NEW_SRV_START *)osi_malloc((UINT16)sizeof(tGATTS_PENDING_NEW_SRV_START))) != NULL) {
        GATT_TRACE_DEBUG ("enqueue a new pending new srv start");
        p_buf->p_new_srv_start = p_new_srv_start;
    fixed_queue_enqueue(gatt_cb.pending_new_srv_start_q, p_buf);
    }
    return p_buf;
}


/*******************************************************************************
**
** Function     gatt_add_srv_chg_clt
**
** Description  Add a service chnage client to the service change client queue
**
** Returns    Pointer to the service change client buffer; Null no buffer available
**
*******************************************************************************/
tGATTS_SRV_CHG *gatt_add_srv_chg_clt(tGATTS_SRV_CHG *p_srv_chg)
{
    tGATTS_SRV_CHG *p_buf;
    GATT_TRACE_DEBUG ("gatt_add_srv_chg_clt");
    if ((p_buf = (tGATTS_SRV_CHG *)osi_malloc((UINT16)sizeof(tGATTS_SRV_CHG))) != NULL) {
        GATT_TRACE_DEBUG ("enqueue a srv chg client");
        memcpy(p_buf, p_srv_chg, sizeof(tGATTS_SRV_CHG));
    fixed_queue_enqueue(gatt_cb.srv_chg_clt_q, p_buf);
    }

    return p_buf;
}


/*******************************************************************************
**
** Function     gatt_alloc_hdl_buffer
**
** Description  Allocate a handle buufer
**
** Returns    Pointer to the allocated buffer, NULL no buffer available
**
*******************************************************************************/
#if (GATTS_INCLUDED == TRUE)
tGATT_HDL_LIST_ELEM *gatt_alloc_hdl_buffer(void)
{
    UINT8 i;
    tGATT_CB    *p_cb = &gatt_cb;
    tGATT_HDL_LIST_ELEM *p_elem = &p_cb->hdl_list[0];

    for (i = 0; i < GATT_MAX_SR_PROFILES; i++, p_elem ++) {
        if (!p_cb->hdl_list[i].in_use) {
            memset(p_elem, 0, sizeof(tGATT_HDL_LIST_ELEM));
            p_elem->in_use = TRUE;
            p_elem->svc_db.svc_buffer = fixed_queue_new(SIZE_MAX);
            return p_elem;
        }
    }

    return NULL;
}

/*******************************************************************************
**
** Function     gatt_find_hdl_buffer_by_handle
**
** Description  Find handle range buffer by service handle.
**
** Returns    Pointer to the buffer, NULL no buffer available
**
*******************************************************************************/
tGATT_HDL_LIST_ELEM *gatt_find_hdl_buffer_by_handle(UINT16 handle)
{
    tGATT_HDL_LIST_INFO *p_list_info = &gatt_cb.hdl_list_info;
    tGATT_HDL_LIST_ELEM      *p_list = NULL;

    p_list = p_list_info->p_first;

    while (p_list != NULL) {
        if (p_list->in_use && p_list->asgn_range.s_handle == handle) {
            return (p_list);
        }
        p_list = p_list->p_next;
    }
    return NULL;
}

/*******************************************************************************
**
** Function     gatt_find_hdl_buffer_by_attr_handle
**
** Description  Find handle range buffer by attribute handle.
**
** Returns    Pointer to the buffer, NULL no buffer available
**
*******************************************************************************/
tGATT_HDL_LIST_ELEM *gatt_find_hdl_buffer_by_attr_handle(UINT16 attr_handle)
{
    tGATT_HDL_LIST_INFO *p_list_info = &gatt_cb.hdl_list_info;
    tGATT_HDL_LIST_ELEM      *p_list = NULL;

    p_list = p_list_info->p_first;

    while (p_list != NULL) {
        if (p_list->in_use && (p_list->asgn_range.s_handle <= attr_handle) 
			&& (p_list->asgn_range.e_handle >= attr_handle)) {
            return (p_list);
        }
        p_list = p_list->p_next;
    }
    return NULL;
}


/*******************************************************************************
**
** Function     gatt_find_hdl_buffer_by_app_id
**
** Description  Find handle range buffer by app ID, service and service instance ID.
**
** Returns    Pointer to the buffer, NULL no buffer available
**
*******************************************************************************/
tGATT_HDL_LIST_ELEM *gatt_find_hdl_buffer_by_app_id (tBT_UUID *p_app_uuid128,
        tBT_UUID *p_svc_uuid,
        UINT16 svc_inst)
{
    tGATT_HDL_LIST_INFO *p_list_info = &gatt_cb.hdl_list_info;
    tGATT_HDL_LIST_ELEM      *p_list = NULL;

    p_list = p_list_info->p_first;

    while (p_list != NULL) {
        if ( gatt_uuid_compare (*p_app_uuid128, p_list->asgn_range.app_uuid128)
                &&  gatt_uuid_compare (*p_svc_uuid,    p_list->asgn_range.svc_uuid)
                &&  (svc_inst == p_list->asgn_range.svc_inst) ) {
            GATT_TRACE_DEBUG ("Already allocated handles for this service before!!");
            return (p_list);
        }
        p_list = p_list->p_next;
    }
    return NULL;
}
#endif  ///GATTS_INCLUDED == TRUE

/*******************************************************************************
**
** Function         gatt_free_attr_value_buffer
**
** Description      free characteristic attribute value buffer in a service
**
** Returns          None
**
*******************************************************************************/
void gatt_free_attr_value_buffer(tGATT_HDL_LIST_ELEM *p)
{
    if (p){
        tGATT_SVC_DB *p_db = &(p->svc_db);
        tGATT_ATTR16 *p_attr = p_db->p_attr_list;
        tGATT_ATTR_VALUE *p_value = NULL;

        while(p_attr){
            if (p_attr->mask & GATT_ATTR_VALUE_ALLOCATED){
                p_value = p_attr->p_value;
                if ((p_value != NULL) && (p_value->attr_val.attr_val != NULL)){
                    osi_free(p_value->attr_val.attr_val);
                }
            }
            p_attr = p_attr->p_next;
        }
    }
}
/*******************************************************************************
**
** Function         gatt_free_hdl_buffer
**
** Description      free a handle buffer
**
** Returns          None
**
*******************************************************************************/
void gatt_free_hdl_buffer(tGATT_HDL_LIST_ELEM *p)
{

    if (p) {
        while (!fixed_queue_is_empty(p->svc_db.svc_buffer)) {
            osi_free(fixed_queue_try_dequeue(p->svc_db.svc_buffer));
		}
        fixed_queue_free(p->svc_db.svc_buffer, NULL);
        memset(p, 0, sizeof(tGATT_HDL_LIST_ELEM));
    }
}
/*******************************************************************************
**
** Function         gatt_free_srvc_db_buffer_app_id
**
** Description      free the service attribute database buffers by the owner of the
**                  service app ID.
**
** Returns       None
**
*******************************************************************************/
#if (GATTS_INCLUDED == TRUE)
void gatt_free_srvc_db_buffer_app_id(tBT_UUID *p_app_id)
{
    tGATT_HDL_LIST_ELEM *p_elem =  &gatt_cb.hdl_list[0];
    UINT8   i;

    for (i = 0; i < GATT_MAX_SR_PROFILES; i ++, p_elem ++) {
        if (memcmp(p_app_id, &p_elem->asgn_range.app_uuid128, sizeof(tBT_UUID)) == 0) {
            gatt_free_attr_value_buffer(p_elem);
            while (!fixed_queue_is_empty(p_elem->svc_db.svc_buffer)) {
                osi_free(fixed_queue_try_dequeue(p_elem->svc_db.svc_buffer));
			}
            fixed_queue_free(p_elem->svc_db.svc_buffer, NULL);
            p_elem->svc_db.svc_buffer = NULL;

            p_elem->svc_db.mem_free = 0;
            p_elem->svc_db.p_attr_list = p_elem->svc_db.p_free_mem = NULL;
        }
    }
}
/*******************************************************************************
**
** Function         gatt_is_last_attribute
**
** Description     Check this is the last attribute of the specified value or not
**
** Returns       TRUE - yes this is the last attribute
**
*******************************************************************************/
BOOLEAN gatt_is_last_attribute(tGATT_SRV_LIST_INFO *p_list, tGATT_SRV_LIST_ELEM *p_start, tBT_UUID value)
{
    tGATT_SRV_LIST_ELEM *p_srv = p_start->p_next;
    BOOLEAN              is_last_attribute = TRUE;
    tGATT_SR_REG        *p_rcb = NULL;
    tBT_UUID            *p_svc_uuid;

    p_list->p_last_primary = NULL;

    while (p_srv) {
        p_rcb = GATT_GET_SR_REG_PTR(p_srv->i_sreg);

        p_svc_uuid = gatts_get_service_uuid (p_rcb->p_db);

        if (gatt_uuid_compare(value, *p_svc_uuid)) {
            is_last_attribute = FALSE;
            break;

        }
        p_srv = p_srv->p_next;
    }

    return is_last_attribute;

}
/*******************************************************************************
**
** Function         gatt_update_last_pri_srv_info
**
** Description     Update the the last primary info for the service list info
**
** Returns       None
**
*******************************************************************************/
void gatt_update_last_pri_srv_info(tGATT_SRV_LIST_INFO *p_list)
{
    tGATT_SRV_LIST_ELEM *p_srv = p_list->p_first;

    p_list->p_last_primary = NULL;

    while (p_srv) {
        if (p_srv->is_primary) {
            p_list->p_last_primary = p_srv;
        }
        p_srv = p_srv->p_next;
    }

}
/*******************************************************************************
**
** Function         gatts_update_srv_list_elem
**
** Description      update an element in the service list.
**
** Returns          None.
**
*******************************************************************************/
void gatts_update_srv_list_elem(UINT8 i_sreg, UINT16 handle, BOOLEAN is_primary)
{
    UNUSED(handle);

    gatt_cb.srv_list[i_sreg].in_use         = TRUE;
    gatt_cb.srv_list[i_sreg].i_sreg    = i_sreg;
    gatt_cb.srv_list[i_sreg].s_hdl          = gatt_cb.sr_reg[i_sreg].s_hdl;
    gatt_cb.srv_list[i_sreg].is_primary     = is_primary;

    return;
}
#endif  ///GATTS_INCLUDED == TRUE

/*******************************************************************************
**
** Function  gatt_add_a_srv_to_list
**
** Description  add an service to the list in ascending
**              order of the start handle
**
** Returns   BOOLEAN TRUE-if add is successful
**
*******************************************************************************/
BOOLEAN gatt_add_a_srv_to_list(tGATT_SRV_LIST_INFO *p_list, tGATT_SRV_LIST_ELEM *p_new)
{
    tGATT_SRV_LIST_ELEM *p_old;

    if (!p_new) {
        GATT_TRACE_DEBUG("p_new==NULL");
        return FALSE;
    }

    if (!p_list->p_first) {
        /* this is an empty list */
        p_list->p_first =
            p_list->p_last  = p_new;
        p_new->p_next   =
            p_new->p_prev   = NULL;
    } else {
        p_old = p_list->p_first;
        while (1) {
            if (p_old == NULL) {
                p_list->p_last->p_next      = p_new;
                p_new->p_prev               = p_list->p_last;
                p_new->p_next               = NULL;
                p_list->p_last              = p_new;
                break;
            } else {
                if (p_new->s_hdl <  p_old->s_hdl) {
                    /* if not the first in list */
                    if (p_old->p_prev != NULL) {
                        p_old->p_prev->p_next   = p_new;
                    } else {
                        p_list->p_first = p_new;
                    }

                    p_new->p_prev           = p_old->p_prev;
                    p_new->p_next           = p_old;
                    p_old->p_prev           = p_new;
                    break;
                }
            }
            p_old = p_old->p_next;
        }
    }
    p_list->count++;

    gatt_update_last_pri_srv_info(p_list);
    return TRUE;

}

/*******************************************************************************
**
** Function  gatt_remove_a_srv_from_list
**
** Description  Remove a service from the list
**
** Returns   BOOLEAN TRUE-if remove is successful
**
*******************************************************************************/
BOOLEAN gatt_remove_a_srv_from_list(tGATT_SRV_LIST_INFO *p_list, tGATT_SRV_LIST_ELEM *p_remove)
{
    if (!p_remove || !p_list->p_first) {
        GATT_TRACE_DEBUG("p_remove==NULL || p_list->p_first==NULL");
        return FALSE;
    }

    if (p_remove->p_prev == NULL) {
        p_list->p_first             = p_remove->p_next;
        if (p_remove->p_next) {
            p_remove->p_next->p_prev    = NULL;
        }
    } else if (p_remove->p_next == NULL) {
        p_list->p_last              = p_remove->p_prev;
        p_remove->p_prev->p_next    = NULL;
    } else {
        p_remove->p_next->p_prev = p_remove->p_prev;
        p_remove->p_prev->p_next = p_remove->p_next;
    }
    p_list->count--;
    gatt_update_last_pri_srv_info(p_list);
    return TRUE;

}

/*******************************************************************************
**
** Function  gatt_add_an_item_to_list
**
** Description  add an service handle range to the list in decending
**              order of the start handle
**
** Returns   BOOLEAN TRUE-if add is successful
**
*******************************************************************************/
BOOLEAN gatt_add_an_item_to_list(tGATT_HDL_LIST_INFO *p_list, tGATT_HDL_LIST_ELEM *p_new)
{
    tGATT_HDL_LIST_ELEM *p_old;
    if (!p_new) {
        GATT_TRACE_DEBUG("p_new==NULL");
        return FALSE;
    }

    if (!p_list->p_first) {
        /* this is an empty list */
        p_list->p_first =
            p_list->p_last  = p_new;
        p_new->p_next   =
            p_new->p_prev   = NULL;
    } else {
        p_old = p_list->p_first;
        while (1) {
            if (p_old == NULL) {
                p_list->p_last->p_next      = p_new;
                p_new->p_prev               = p_list->p_last;
                p_new->p_next               = NULL;
                p_list->p_last              = p_new;

                break;

            } else {
                if (p_new->asgn_range.s_handle >  p_old->asgn_range.s_handle) {
                    if (p_old == p_list->p_first) {
                        p_list->p_first = p_new;
                    }

                    p_new->p_prev    = p_old->p_prev;
                    p_new->p_next    = p_old;


                    p_old->p_prev    = p_new;
                    break;
                }
            }
            p_old = p_old->p_next;
        }
    }
    p_list->count++;
    return TRUE;

}

/*******************************************************************************
**
** Function  gatt_remove_an_item_from_list
**
** Description  Remove an service handle range from the list
**
** Returns   BOOLEAN TRUE-if remove is successful
**
*******************************************************************************/
BOOLEAN gatt_remove_an_item_from_list(tGATT_HDL_LIST_INFO *p_list, tGATT_HDL_LIST_ELEM *p_remove)
{
    if (!p_remove || !p_list->p_first) {
        GATT_TRACE_DEBUG("p_remove==NULL || p_list->p_first==NULL");
        return FALSE;
    }

    if (p_remove->p_prev == NULL) {
        p_list->p_first             = p_remove->p_next;
        if (p_remove->p_next) {
            p_remove->p_next->p_prev    = NULL;
        }
    } else if (p_remove->p_next == NULL) {
        p_list->p_last              = p_remove->p_prev;
        p_remove->p_prev->p_next    = NULL;
    } else {
        p_remove->p_next->p_prev = p_remove->p_prev;
        p_remove->p_prev->p_next = p_remove->p_next;
    }
    p_list->count--;
    return TRUE;

}

/*******************************************************************************
**
** Function         gatt_find_the_connected_bda
**
** Description      This function find the connected bda
**
** Returns           TRUE if found
**
*******************************************************************************/
BOOLEAN gatt_find_the_connected_bda(UINT8 start_idx, BD_ADDR bda, UINT8 *p_found_idx,
                                    tBT_TRANSPORT *p_transport)
{
    UINT8 i;
    BOOLEAN found = FALSE;
    GATT_TRACE_DEBUG("gatt_find_the_connected_bda start_idx=%d", start_idx);

    for (i = start_idx ; i < GATT_MAX_PHY_CHANNEL; i ++) {
        if (gatt_cb.tcb[i].in_use && gatt_cb.tcb[i].ch_state == GATT_CH_OPEN) {
            memcpy( bda, gatt_cb.tcb[i].peer_bda, BD_ADDR_LEN);
            *p_found_idx = i;
            *p_transport = gatt_cb.tcb[i].transport;
            found = TRUE;
            GATT_TRACE_DEBUG("gatt_find_the_connected_bda bda :%02x-%02x-%02x-%02x-%02x-%02x",
                             bda[0],  bda[1], bda[2],  bda[3], bda[4],  bda[5]);
            break;
        }
    }
    GATT_TRACE_DEBUG("gatt_find_the_connected_bda found=%d found_idx=%d", found, i);
    return found;
}



/*******************************************************************************
**
** Function         gatt_is_srv_chg_ind_pending
**
** Description      Check whether a service chnaged is in the indication pending queue
**                  or waiting for an Ack already
**
** Returns         BOOLEAN
**
*******************************************************************************/
BOOLEAN gatt_is_srv_chg_ind_pending (tGATT_TCB *p_tcb)
{
    BOOLEAN srv_chg_ind_pending = FALSE;

    GATT_TRACE_DEBUG("gatt_is_srv_chg_ind_pending is_queue_empty=%d",
                     fixed_queue_is_empty(p_tcb->pending_ind_q));

    if (p_tcb->indicate_handle == gatt_cb.handle_of_h_r) {
        srv_chg_ind_pending = TRUE;
    } else if (! fixed_queue_is_empty(p_tcb->pending_ind_q)) {
        list_t *list = fixed_queue_get_list(p_tcb->pending_ind_q);
        for (const list_node_t *node = list_begin(list);
             node != list_end(list);
             node = list_next(node)) {
            tGATT_VALUE *p_buf = (tGATT_VALUE *)list_node(node);
            if (p_buf->handle == gatt_cb.handle_of_h_r)
            {
                srv_chg_ind_pending = TRUE;
                break;
            }
        }
    }

    GATT_TRACE_DEBUG("srv_chg_ind_pending = %d", srv_chg_ind_pending);
    return srv_chg_ind_pending;
}


/*******************************************************************************
**
** Function         gatt_is_bda_in_the_srv_chg_clt_list
**
** Description      This function check the specified bda is in the srv chg clinet list or not
**
** Returns         pointer to the found elemenet otherwise NULL
**
*******************************************************************************/
tGATTS_SRV_CHG *gatt_is_bda_in_the_srv_chg_clt_list (BD_ADDR bda)
{
    tGATTS_SRV_CHG *p_buf = NULL;

    GATT_TRACE_DEBUG("gatt_is_bda_in_the_srv_chg_clt_list :%02x-%02x-%02x-%02x-%02x-%02x",
                     bda[0],  bda[1], bda[2],  bda[3], bda[4],  bda[5]);

    if (fixed_queue_is_empty(gatt_cb.srv_chg_clt_q)) {
        return NULL;
	}

    list_t *list = fixed_queue_get_list(gatt_cb.srv_chg_clt_q);
    for (const list_node_t *node = list_begin(list); node != list_end(list);
         node = list_next(node)) {
        tGATTS_SRV_CHG *p_buf = (tGATTS_SRV_CHG *)list_node(node);
        if (!memcmp( bda, p_buf->bda, BD_ADDR_LEN)) {
            GATT_TRACE_DEBUG("bda is in the srv chg clt list");
            break;
        }
    }

    return p_buf;
}


/*******************************************************************************
**
** Function         gatt_is_bda_connected
**
** Description
**
** Returns           GATT_INDEX_INVALID if not found. Otherwise index to the tcb.
**
*******************************************************************************/
BOOLEAN gatt_is_bda_connected(BD_ADDR bda)
{
    UINT8 i = 0;
    BOOLEAN connected = FALSE;

    for ( i = 0; i < GATT_MAX_PHY_CHANNEL; i ++) {
        if (gatt_cb.tcb[i].in_use &&
                !memcmp(gatt_cb.tcb[i].peer_bda, bda, BD_ADDR_LEN)) {
            connected = TRUE;
            break;
        }
    }
    return connected;
}

/*******************************************************************************
**
** Function         gatt_find_i_tcb_by_addr
**
** Description      The function searches for an empty tcb entry, and return the index.
**
** Returns           GATT_INDEX_INVALID if not found. Otherwise index to the tcb.
**
*******************************************************************************/
UINT8 gatt_find_i_tcb_by_addr(BD_ADDR bda, tBT_TRANSPORT transport)
{
    UINT8 i = 0;

    for ( ; i < GATT_MAX_PHY_CHANNEL; i ++) {
        if (!memcmp(gatt_cb.tcb[i].peer_bda, bda, BD_ADDR_LEN) &&
                gatt_cb.tcb[i].transport == transport) {
            return i;
        }
    }
    return GATT_INDEX_INVALID;
}


/*******************************************************************************
**
** Function         gatt_get_tcb_by_idx
**
** Description      The function get TCB using the TCB index
**
** Returns           NULL if not found. Otherwise index to the tcb.
**
*******************************************************************************/
tGATT_TCB *gatt_get_tcb_by_idx(UINT8 tcb_idx)
{
    tGATT_TCB   *p_tcb = NULL;

    if ( (tcb_idx < GATT_MAX_PHY_CHANNEL) && gatt_cb.tcb[tcb_idx].in_use) {
        p_tcb = &gatt_cb.tcb[tcb_idx];
    }

    return p_tcb;
}

/*******************************************************************************
**
** Function         gatt_find_tcb_by_addr
**
** Description      The function searches for an empty tcb entry, and return pointer.
**
** Returns           NULL if not found. Otherwise index to the tcb.
**
*******************************************************************************/
tGATT_TCB *gatt_find_tcb_by_addr(BD_ADDR bda, tBT_TRANSPORT transport)
{
    tGATT_TCB   *p_tcb = NULL;
    UINT8 i = 0;

    if ((i = gatt_find_i_tcb_by_addr(bda, transport)) != GATT_INDEX_INVALID) {
        p_tcb = &gatt_cb.tcb[i];
    }

    return p_tcb;
}
/*******************************************************************************
**
** Function         gatt_find_i_tcb_free
**
** Description      The function searches for an empty tcb entry, and return the index.
**
** Returns           GATT_INDEX_INVALID if not found. Otherwise index to the tcb.
**
*******************************************************************************/
UINT8 gatt_find_i_tcb_free(void)
{
    UINT8 i = 0, j = GATT_INDEX_INVALID;

    for (i = 0; i < GATT_MAX_PHY_CHANNEL; i ++) {
        if (!gatt_cb.tcb[i].in_use) {
            j = i;
            break;
        }
    }
    return j;
}
/*******************************************************************************
**
** Function         gatt_allocate_tcb_by_bdaddr
**
** Description      The function locate or allocate new tcb entry for matching bda.
**
** Returns           GATT_INDEX_INVALID if not found. Otherwise index to the tcb.
**
*******************************************************************************/
tGATT_TCB *gatt_allocate_tcb_by_bdaddr(BD_ADDR bda, tBT_TRANSPORT transport)
{
    UINT8 i = 0;
    BOOLEAN allocated = FALSE;
    tGATT_TCB    *p_tcb = NULL;

    /* search for existing tcb with matching bda    */
    i = gatt_find_i_tcb_by_addr(bda, transport);
    /* find free tcb */
    if (i == GATT_INDEX_INVALID) {
        i = gatt_find_i_tcb_free();
        allocated = TRUE;
    }
    if (i != GATT_INDEX_INVALID) {
        p_tcb = &gatt_cb.tcb[i];

        if (allocated) {
            memset(p_tcb, 0, sizeof(tGATT_TCB));
            p_tcb->pending_enc_clcb = fixed_queue_new(SIZE_MAX);
            p_tcb->pending_ind_q = fixed_queue_new(SIZE_MAX);
            p_tcb->in_use = TRUE;
            p_tcb->tcb_idx = i;
            p_tcb->transport = transport;
        }
        memcpy(p_tcb->peer_bda, bda, BD_ADDR_LEN);
    }
    return p_tcb;
}

/*******************************************************************************
**
** Function         gatt_convert_uuid16_to_uuid128
**
** Description      Convert a 16 bits UUID to be an standard 128 bits one.
**
** Returns          TRUE if two uuid match; FALSE otherwise.
**
*******************************************************************************/
void gatt_convert_uuid16_to_uuid128(UINT8 uuid_128[LEN_UUID_128], UINT16 uuid_16)
{
    UINT8   *p = &uuid_128[LEN_UUID_128 - 4];

    memcpy (uuid_128, base_uuid, LEN_UUID_128);

    UINT16_TO_STREAM(p, uuid_16);
}

/*******************************************************************************
**
** Function         gatt_convert_uuid32_to_uuid128
**
** Description      Convert a 32 bits UUID to be an standard 128 bits one.
**
** Returns          TRUE if two uuid match; FALSE otherwise.
**
*******************************************************************************/
void gatt_convert_uuid32_to_uuid128(UINT8 uuid_128[LEN_UUID_128], UINT32 uuid_32)
{
    UINT8   *p = &uuid_128[LEN_UUID_128 - 4];

    memcpy (uuid_128, base_uuid, LEN_UUID_128);

    UINT32_TO_STREAM(p, uuid_32);
}
/*******************************************************************************
**
** Function         gatt_uuid_compare
**
** Description      Compare two UUID to see if they are the same.
**
** Returns          TRUE if two uuid match; FALSE otherwise.
**
*******************************************************************************/
BOOLEAN gatt_uuid_compare (tBT_UUID src, tBT_UUID tar)
{
    UINT8  su[LEN_UUID_128], tu[LEN_UUID_128];
    UINT8  *ps, *pt;

    /* any of the UUID is unspecified */
    if (src.len == 0 || tar.len == 0) {
        return TRUE;
    }

    /* If both are 16-bit, we can do a simple compare */
    if (src.len == LEN_UUID_16 && tar.len == LEN_UUID_16) {
        return src.uu.uuid16 == tar.uu.uuid16;
    }

    /* If both are 32-bit, we can do a simple compare */
    if (src.len == LEN_UUID_32 && tar.len == LEN_UUID_32) {
        return src.uu.uuid32 == tar.uu.uuid32;
    }

    /* One or both of the UUIDs is 128-bit */
    if (src.len == LEN_UUID_16) {
        /* convert a 16 bits UUID to 128 bits value */
        gatt_convert_uuid16_to_uuid128(su, src.uu.uuid16);
        ps = su;
    } else if (src.len == LEN_UUID_32) {
        gatt_convert_uuid32_to_uuid128(su, src.uu.uuid32);
        ps = su;
    } else {
        ps = src.uu.uuid128;
    }

    if (tar.len == LEN_UUID_16) {
        /* convert a 16 bits UUID to 128 bits value */
        gatt_convert_uuid16_to_uuid128(tu, tar.uu.uuid16);
        pt = tu;
    } else if (tar.len == LEN_UUID_32) {
        /* convert a 32 bits UUID to 128 bits value */
        gatt_convert_uuid32_to_uuid128(tu, tar.uu.uuid32);
        pt = tu;
    } else {
        pt = tar.uu.uuid128;
    }

    return (memcmp(ps, pt, LEN_UUID_128) == 0);
}

/*******************************************************************************
**
** Function         gatt_build_uuid_to_stream
**
** Description      Add UUID into stream.
**
** Returns          UUID length.
**
*******************************************************************************/
UINT8 gatt_build_uuid_to_stream(UINT8 **p_dst, tBT_UUID uuid)
{
    UINT8   *p = *p_dst;
    UINT8   len = 0;

    if (uuid.len == LEN_UUID_16) {
        UINT16_TO_STREAM (p, uuid.uu.uuid16);
        len = LEN_UUID_16;
    } else if (uuid.len == LEN_UUID_32) { /* always convert 32 bits into 128 bits as alwats */
        gatt_convert_uuid32_to_uuid128(p, uuid.uu.uuid32);
        p += LEN_UUID_128;
        len = LEN_UUID_128;
    } else if (uuid.len == LEN_UUID_128) {
        ARRAY_TO_STREAM (p, uuid.uu.uuid128, LEN_UUID_128);
        len = LEN_UUID_128;
    }

    *p_dst = p;
    return len;
}

/*******************************************************************************
**
** Function         gatt_parse_uuid_from_cmd
**
** Description      Convert a 128 bits UUID into a 16 bits UUID.
**
** Returns          TRUE if command sent, otherwise FALSE.
**
*******************************************************************************/
BOOLEAN gatt_parse_uuid_from_cmd(tBT_UUID *p_uuid_rec, UINT16 uuid_size, UINT8 **p_data)
{
    BOOLEAN is_base_uuid, ret = TRUE;
    UINT8  xx;
    UINT8 *p_uuid = *p_data;

    memset(p_uuid_rec, 0, sizeof(tBT_UUID));

    switch (uuid_size) {
    case LEN_UUID_16:
        p_uuid_rec->len = uuid_size;
        STREAM_TO_UINT16 (p_uuid_rec->uu.uuid16, p_uuid);
        *p_data += LEN_UUID_16;
        break;

    case LEN_UUID_128:
        /* See if we can compress his UUID down to 16 or 32bit UUIDs */
        is_base_uuid = TRUE;
        for (xx = 0; xx < LEN_UUID_128 - 4; xx++) {
            if (p_uuid[xx] != base_uuid[xx]) {
                is_base_uuid = FALSE;
                break;
            }
        }
        if (is_base_uuid) {
            if ((p_uuid[LEN_UUID_128 - 1] == 0) && (p_uuid[LEN_UUID_128 - 2] == 0)) {
                p_uuid += (LEN_UUID_128 - 4);
                p_uuid_rec->len = LEN_UUID_16;
                STREAM_TO_UINT16(p_uuid_rec->uu.uuid16, p_uuid);
            } else {
                p_uuid += (LEN_UUID_128 - LEN_UUID_32);
                p_uuid_rec->len = LEN_UUID_32;
                STREAM_TO_UINT32(p_uuid_rec->uu.uuid32, p_uuid);
            }
        }
        if (!is_base_uuid) {
            p_uuid_rec->len = LEN_UUID_128;
            memcpy(p_uuid_rec->uu.uuid128, p_uuid, LEN_UUID_128);
        }
        *p_data += LEN_UUID_128;
        break;

    /* do not allow 32 bits UUID in ATT PDU now */
    case LEN_UUID_32:
        GATT_TRACE_ERROR("DO NOT ALLOW 32 BITS UUID IN ATT PDU");
    case 0:
    default:
        if (uuid_size != 0) {
            ret = FALSE;
        }
        GATT_TRACE_WARNING("gatt_parse_uuid_from_cmd invalid uuid size");
        break;
    }

    return ( ret);
}

/*******************************************************************************
**
** Function         gatt_start_rsp_timer
**
** Description      Start a wait_for_response timer.
**
** Returns          TRUE if command sent, otherwise FALSE.
**
*******************************************************************************/
void gatt_start_rsp_timer(UINT16 clcb_idx)
{
    tGATT_CLCB *p_clcb = &gatt_cb.clcb[clcb_idx];
    UINT32 timeout = GATT_WAIT_FOR_RSP_TOUT;
    p_clcb->rsp_timer_ent.param  = (TIMER_PARAM_TYPE)p_clcb;
    if (p_clcb->operation == GATTC_OPTYPE_DISCOVERY &&
            p_clcb->op_subtype == GATT_DISC_SRVC_ALL) {
        timeout = GATT_WAIT_FOR_DISC_RSP_TOUT;
    }
    btu_start_timer (&p_clcb->rsp_timer_ent, BTU_TTYPE_ATT_WAIT_FOR_RSP,
                     timeout);
}
/*******************************************************************************
**
** Function         gatt_start_conf_timer
**
** Description      Start a wait_for_confirmation timer.
**
** Returns          TRUE if command sent, otherwise FALSE.
**
*******************************************************************************/
void gatt_start_conf_timer(tGATT_TCB    *p_tcb)
{
    p_tcb->conf_timer_ent.param  = (TIMER_PARAM_TYPE)p_tcb;
    btu_start_timer (&p_tcb->conf_timer_ent, BTU_TTYPE_ATT_WAIT_FOR_RSP,
                     GATT_WAIT_FOR_RSP_TOUT);
}
/*******************************************************************************
**
** Function         gatt_start_ind_ack_timer
**
** Description      start the application ack timer
**
** Returns          void
**
*******************************************************************************/
void gatt_start_ind_ack_timer(tGATT_TCB *p_tcb)
{
    p_tcb->ind_ack_timer_ent.param  = (TIMER_PARAM_TYPE)p_tcb;
    /* start notification cache timer */
    btu_start_timer (&p_tcb->ind_ack_timer_ent, BTU_TTYPE_ATT_WAIT_FOR_IND_ACK,
                     GATT_WAIT_FOR_RSP_TOUT);

}
/*******************************************************************************
**
** Function         gatt_rsp_timeout
**
** Description      Called when GATT wait for ATT command response timer expires
**
** Returns          void
**
*******************************************************************************/
void gatt_rsp_timeout(TIMER_LIST_ENT *p_tle)
{
    tGATT_CLCB *p_clcb = (tGATT_CLCB *)p_tle->param;
    if (p_clcb == NULL || p_clcb->p_tcb == NULL) {
        GATT_TRACE_WARNING("gatt_rsp_timeout clcb is already deleted");
        return;
    }
    if (p_clcb->operation == GATTC_OPTYPE_DISCOVERY &&
            p_clcb->op_subtype == GATT_DISC_SRVC_ALL &&
            p_clcb->retry_count < GATT_REQ_RETRY_LIMIT) {
        UINT8 rsp_code;
        GATT_TRACE_WARNING("gatt_rsp_timeout retry discovery primary service");
        if (p_clcb != gatt_cmd_dequeue(p_clcb->p_tcb, &rsp_code)) {
            GATT_TRACE_ERROR("gatt_rsp_timeout command queue out of sync, disconnect");
        } else {
            p_clcb->retry_count++;
#if (GATTC_INCLUDED == TRUE)
            gatt_act_discovery(p_clcb);
#endif  ///GATTC_INCLUDED == TRUE
            return;
        }
    }

    GATT_TRACE_WARNING("gatt_rsp_timeout disconnecting...");
    gatt_disconnect (p_clcb->p_tcb);
}

/*******************************************************************************
**
** Function         gatt_ind_ack_timeout
**
** Description      Called when GATT wait for ATT handle confirmation timeout
**
** Returns          void
**
*******************************************************************************/
void gatt_ind_ack_timeout(TIMER_LIST_ENT *p_tle)
{
    tGATT_TCB *p_tcb = (tGATT_TCB *)p_tle->param;

    GATT_TRACE_WARNING("gatt_ind_ack_timeout send ack now");

    if (p_tcb != NULL) {
        p_tcb->ind_count = 0;
    }

    attp_send_cl_msg(((tGATT_TCB *)p_tle->param), 0, GATT_HANDLE_VALUE_CONF, NULL);
}
/*******************************************************************************
**
** Function         gatt_sr_find_i_rcb_by_handle
**
** Description      The function searches for a service that owns a specific handle.
**
** Returns          GATT_MAX_SR_PROFILES if not found. Otherwise index of th eservice.
**
*******************************************************************************/
UINT8 gatt_sr_find_i_rcb_by_handle(UINT16 handle)
{
    UINT8  i_rcb = 0;

    for ( ; i_rcb < GATT_MAX_SR_PROFILES; i_rcb++) {
        if (gatt_cb.sr_reg[i_rcb].in_use &&
                gatt_cb.sr_reg[i_rcb].s_hdl <= handle &&
                gatt_cb.sr_reg[i_rcb].e_hdl >= handle ) {
            break;
        }
    }
    return i_rcb;
}

/*******************************************************************************
**
** Function         gatt_sr_find_i_rcb_by_handle
**
** Description      The function searches for a service that owns a specific handle.
**
** Returns          0 if not found. Otherwise index of th eservice.
**
*******************************************************************************/
#if (GATTS_INCLUDED == TRUE)
UINT8 gatt_sr_find_i_rcb_by_app_id(tBT_UUID *p_app_uuid128, tBT_UUID *p_svc_uuid, UINT16 svc_inst)
{
    UINT8           i_rcb = 0;
    tGATT_SR_REG    *p_sreg;
    tBT_UUID        *p_this_uuid;

    for (i_rcb = 0, p_sreg = gatt_cb.sr_reg; i_rcb < GATT_MAX_SR_PROFILES; i_rcb++, p_sreg++) {
        if ( p_sreg->in_use ) {
            p_this_uuid = gatts_get_service_uuid (p_sreg->p_db);

            if (p_this_uuid &&
                    gatt_uuid_compare (*p_app_uuid128, p_sreg->app_uuid ) &&
                    gatt_uuid_compare (*p_svc_uuid, *p_this_uuid) &&
                    (svc_inst == p_sreg->service_instance)) {
                GATT_TRACE_ERROR ("Active Service Found ");
                gatt_dbg_display_uuid(*p_svc_uuid);

                break;
            }
        }
    }
    return i_rcb;
}
#endif  ///GATTS_INCLUDED == TRUE
/*******************************************************************************
**
** Function         gatt_sr_find_i_rcb_by_handle
**
** Description      The function searches for a service that owns a specific handle.
**
** Returns          0 if not found. Otherwise index of th eservice.
**
*******************************************************************************/
UINT8 gatt_sr_alloc_rcb(tGATT_HDL_LIST_ELEM *p_list )
{
    UINT8   ii = 0;
    tGATT_SR_REG    *p_sreg = NULL;

    /*this is a new application servoce start */
    for (ii = 0, p_sreg = gatt_cb.sr_reg; ii < GATT_MAX_SR_PROFILES; ii++, p_sreg++) {
        if (!p_sreg->in_use) {
            memset (p_sreg, 0, sizeof(tGATT_SR_REG));

            p_sreg->in_use = TRUE;
            memcpy (&p_sreg->app_uuid, &p_list->asgn_range.app_uuid128, sizeof(tBT_UUID));

            p_sreg->service_instance    = p_list->asgn_range.svc_inst;
            p_sreg->type                = p_list->asgn_range.is_primary ? GATT_UUID_PRI_SERVICE : GATT_UUID_SEC_SERVICE;
            p_sreg->s_hdl               = p_list->asgn_range.s_handle;
            p_sreg->e_hdl               = p_list->asgn_range.e_handle;
            p_sreg->p_db                = &p_list->svc_db;

            GATT_TRACE_DEBUG ("total buffer in db [%d]", fixed_queue_length(p_sreg->p_db->svc_buffer));
            break;
        }
    }

    return ii;
}
/*******************************************************************************
**
** Function         gatt_sr_get_sec_info
**
** Description      Get the security flag and key size information for the peer
**                  device.
**
** Returns          void
**
*******************************************************************************/
void gatt_sr_get_sec_info(BD_ADDR rem_bda, tBT_TRANSPORT transport, UINT8 *p_sec_flag, UINT8 *p_key_size)
{
    UINT8           sec_flag = 0;

    BTM_GetSecurityFlagsByTransport(rem_bda, &sec_flag, transport);

    sec_flag &= (GATT_SEC_FLAG_LKEY_UNAUTHED | GATT_SEC_FLAG_LKEY_AUTHED | GATT_SEC_FLAG_ENCRYPTED);
#if (SMP_INCLUDED == TRUE)
    *p_key_size = btm_ble_read_sec_key_size(rem_bda);
#endif  ///SMP_INCLUDED == TRUE
    *p_sec_flag = sec_flag;
}
/*******************************************************************************
**
** Function         gatt_sr_send_req_callback
**
** Description
**
**
** Returns          void
**
*******************************************************************************/
void gatt_sr_send_req_callback(UINT16 conn_id,
                               UINT32 trans_id,
                               tGATTS_REQ_TYPE type, tGATTS_DATA *p_data)
{
    tGATT_IF        gatt_if = GATT_GET_GATT_IF(conn_id);
    tGATT_REG       *p_reg = gatt_get_regcb(gatt_if);

    if (!p_reg ) {
        GATT_TRACE_ERROR ("p_reg not found discard request");
        return;
    }

    if ( p_reg->in_use &&
            p_reg->app_cb.p_req_cb) {
        (*p_reg->app_cb.p_req_cb)(conn_id, trans_id, type, p_data);
    } else {
        GATT_TRACE_WARNING("Call back not found for application conn_id=%d", conn_id);
    }

}

/*******************************************************************************
**
** Function         gatt_send_error_rsp
**
** Description      This function sends an error response.
**
** Returns          void
**
*******************************************************************************/
tGATT_STATUS gatt_send_error_rsp (tGATT_TCB *p_tcb, UINT8 err_code, UINT8 op_code,
                                  UINT16 handle, BOOLEAN deq)
{
    tGATT_ERROR      error;
    tGATT_STATUS     status;
    BT_HDR           *p_buf;

    error.cmd_code = op_code;
    error.reason = err_code;
    error.handle = handle;

    if ((p_buf = attp_build_sr_msg(p_tcb, GATT_RSP_ERROR, (tGATT_SR_MSG *)&error)) != NULL) {
        status = attp_send_sr_msg (p_tcb, p_buf);
    } else {
        status = GATT_INSUF_RESOURCE;
    }
#if (GATTS_INCLUDED == TRUE)
    if (deq) {
        gatt_dequeue_sr_cmd(p_tcb);
    }
#endif  ///GATTS_INCLUDED == TRUE
    return status;
}

#if (SDP_INCLUDED == TRUE)
/*******************************************************************************
**
** Function         gatt_add_sdp_record
**
** Description      This function add a SDP record for a GATT primary service
**
** Returns          0 if error else sdp handle for the record.
**
*******************************************************************************/
UINT32 gatt_add_sdp_record (tBT_UUID *p_uuid, UINT16 start_hdl, UINT16 end_hdl)
{
    tSDP_PROTOCOL_ELEM  proto_elem_list[2];
    UINT32              sdp_handle;
    UINT16              list = UUID_SERVCLASS_PUBLIC_BROWSE_GROUP;
    UINT8               buff[60];
    UINT8               *p = buff;

    GATT_TRACE_DEBUG("gatt_add_sdp_record s_hdl=0x%x  s_hdl=0x%x", start_hdl, end_hdl);

    if ((sdp_handle = SDP_CreateRecord()) == 0) {
        return 0;
    }

    switch (p_uuid->len) {
    case LEN_UUID_16:
        SDP_AddServiceClassIdList(sdp_handle, 1, &p_uuid->uu.uuid16);
        break;

    case LEN_UUID_32:
        UINT8_TO_BE_STREAM (p, (UUID_DESC_TYPE << 3) | SIZE_FOUR_BYTES);
        UINT32_TO_BE_STREAM (p, p_uuid->uu.uuid32);
        SDP_AddAttribute (sdp_handle, ATTR_ID_SERVICE_CLASS_ID_LIST, DATA_ELE_SEQ_DESC_TYPE,
                          (UINT32) (p - buff), buff);
        break;

    case LEN_UUID_128:
        UINT8_TO_BE_STREAM (p, (UUID_DESC_TYPE << 3) | SIZE_SIXTEEN_BYTES);
        ARRAY_TO_BE_STREAM_REVERSE (p, p_uuid->uu.uuid128, LEN_UUID_128);
        SDP_AddAttribute (sdp_handle, ATTR_ID_SERVICE_CLASS_ID_LIST, DATA_ELE_SEQ_DESC_TYPE,
                          (UINT32) (p - buff), buff);
        break;

    default:
        GATT_TRACE_ERROR("inavlid UUID len=%d", p_uuid->len);
        SDP_DeleteRecord(sdp_handle);
        return 0;
        break;
    }

    /*** Fill out the protocol element sequence for SDP ***/
    proto_elem_list[0].protocol_uuid = UUID_PROTOCOL_L2CAP;
    proto_elem_list[0].num_params    = 1;
    proto_elem_list[0].params[0]     = BT_PSM_ATT;
    proto_elem_list[1].protocol_uuid = UUID_PROTOCOL_ATT;
    proto_elem_list[1].num_params    = 2;
    proto_elem_list[1].params[0]     = start_hdl;
    proto_elem_list[1].params[1]     = end_hdl;

    SDP_AddProtocolList(sdp_handle, 2, proto_elem_list);

    /* Make the service browseable */
    SDP_AddUuidSequence (sdp_handle, ATTR_ID_BROWSE_GROUP_LIST, 1, &list);

    return (sdp_handle);
}
#endif  ///SDP_INCLUDED == TRUE

#if GATT_CONFORMANCE_TESTING == TRUE
/*******************************************************************************
**
** Function         gatt_set_err_rsp
**
** Description      This function is called to set the test confirm value
**
** Returns          void
**
*******************************************************************************/
void gatt_set_err_rsp(BOOLEAN enable, UINT8 req_op_code, UINT8 err_status)
{
    GATT_TRACE_DEBUG("gatt_set_err_rsp enable=%d op_code=%d, err_status=%d", enable, req_op_code, err_status);
    gatt_cb.enable_err_rsp  = enable;
    gatt_cb.req_op_code     = req_op_code;
    gatt_cb.err_status      = err_status;
}
#endif



/*******************************************************************************
**
** Function         gatt_get_regcb
**
** Description      The function returns the registration control block.
**
** Returns          pointer to the registration control block or NULL
**
*******************************************************************************/
tGATT_REG *gatt_get_regcb (tGATT_IF gatt_if)
{
    UINT8           ii = (UINT8)gatt_if;
    tGATT_REG       *p_reg = NULL;

    if (ii < 1 || ii > GATT_MAX_APPS) {
        GATT_TRACE_WARNING("gatt_if out of range [ = %d]", ii);
        return NULL;
    }

    // Index for cl_rcb is always 1 less than gatt_if.
    p_reg = &gatt_cb.cl_rcb[ii - 1];

    if (!p_reg->in_use) {
        GATT_TRACE_WARNING("gatt_if found but not in use.\n");
        return NULL;
    }

    return p_reg;
}


/*******************************************************************************
**
** Function         gatt_is_clcb_allocated
**
** Description      The function check clcb for conn_id is allocated or not
**
** Returns           True already allocated
**
*******************************************************************************/

BOOLEAN gatt_is_clcb_allocated (UINT16 conn_id)
{
    UINT8         i = 0;
    BOOLEAN       is_allocated = FALSE;

    for (i = 0; i < GATT_CL_MAX_LCB; i++) {
        if (gatt_cb.clcb[i].in_use && (gatt_cb.clcb[i].conn_id == conn_id)) {
            is_allocated = TRUE;
            break;
        }
    }

    return is_allocated;
}

/*******************************************************************************
**
** Function         gatt_clcb_alloc
**
** Description      The function allocates a GATT  connection link control block
**
** Returns           NULL if not found. Otherwise pointer to the connection link block.
**
*******************************************************************************/
tGATT_CLCB *gatt_clcb_alloc (UINT16 conn_id)
{
    UINT8           i = 0;
    tGATT_CLCB      *p_clcb = NULL;
    tGATT_IF        gatt_if = GATT_GET_GATT_IF(conn_id);
    UINT8           tcb_idx = GATT_GET_TCB_IDX(conn_id);
    tGATT_TCB       *p_tcb = gatt_get_tcb_by_idx(tcb_idx);
    tGATT_REG       *p_reg = gatt_get_regcb(gatt_if);

    for (i = 0; i < GATT_CL_MAX_LCB; i++) {
        if (!gatt_cb.clcb[i].in_use) {
            p_clcb = &gatt_cb.clcb[i];

            p_clcb->in_use      = TRUE;
            p_clcb->conn_id     = conn_id;
            p_clcb->clcb_idx    = i;
            p_clcb->p_reg       = p_reg;
            p_clcb->p_tcb       = p_tcb;
            break;
        }
    }
    return p_clcb;
}

/*******************************************************************************
**
** Function         gatt_clcb_dealloc
**
** Description      The function de allocates a GATT  connection link control block
**
** Returns         None
**
*******************************************************************************/
void gatt_clcb_dealloc (tGATT_CLCB *p_clcb)
{
    if (p_clcb && p_clcb->in_use) {
        memset(p_clcb, 0, sizeof(tGATT_CLCB));
    }
}



/*******************************************************************************
**
** Function         gatt_find_tcb_by_cid
**
** Description      The function searches for an empty entry
**                   in registration info table for GATT client
**
** Returns           NULL if not found. Otherwise pointer to the rcb.
**
*******************************************************************************/
tGATT_TCB *gatt_find_tcb_by_cid (UINT16 lcid)
{
    UINT16       xx = 0;
    tGATT_TCB    *p_tcb = NULL;

    for (xx = 0; xx < GATT_MAX_PHY_CHANNEL; xx++) {
        if (gatt_cb.tcb[xx].in_use && gatt_cb.tcb[xx].att_lcid == lcid) {
            p_tcb = &gatt_cb.tcb[xx];
            break;
        }
    }
    return p_tcb;
}


/*******************************************************************************
**
** Function         gatt_num_apps_hold_link
**
** Description      The function find the number of applcaitions is holding the link
**
** Returns          total number of applications holding this acl link.
**
*******************************************************************************/
UINT8 gatt_num_apps_hold_link(tGATT_TCB *p_tcb)
{
    UINT8 i, num = 0;

    for (i = 0; i < GATT_MAX_APPS; i ++) {
        if (p_tcb->app_hold_link[i]) {
            num ++;
        }
    }

    GATT_TRACE_DEBUG("gatt_num_apps_hold_link   num=%d",  num);
    return num;
}


/*******************************************************************************
**
** Function         gatt_num_clcb_by_bd_addr
**
** Description      The function searches all LCB with macthing bd address
**
** Returns          total number of clcb found.
**
*******************************************************************************/
UINT8 gatt_num_clcb_by_bd_addr(BD_ADDR bda)
{
    UINT8 i, num = 0;

    for (i = 0; i < GATT_CL_MAX_LCB; i ++) {
        if (gatt_cb.clcb[i].in_use && memcmp(gatt_cb.clcb[i].p_tcb->peer_bda, bda, BD_ADDR_LEN) == 0) {
            num ++;
        }
    }
    return num;
}

/*******************************************************************************
**
** Function         gatt_sr_update_cback_cnt
**
** Description      The function searches all LCB with macthing bd address
**
** Returns          total number of clcb found.
**
*******************************************************************************/
void gatt_sr_copy_prep_cnt_to_cback_cnt(tGATT_TCB *p_tcb )
{
#if (GATTS_INCLUDED == TRUE)
    UINT8 i;

    if (p_tcb) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            if (p_tcb->prep_cnt[i]) {
                p_tcb->sr_cmd.cback_cnt[i] = 1;
            }
        }
    }
#endif  ///GATTS_INCLUDED == TRUE
}

/*******************************************************************************
**
** Function         gatt_sr_is_cback_cnt_zero
**
** Description      The function searches all LCB with macthing bd address
**
** Returns          True if thetotal application callback count is zero
**
*******************************************************************************/
BOOLEAN gatt_sr_is_cback_cnt_zero(tGATT_TCB *p_tcb )
{
    BOOLEAN status = TRUE;
#if (GATTS_INCLUDED == TRUE)
    UINT8   i;

    if (p_tcb) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            if (p_tcb->sr_cmd.cback_cnt[i]) {
                status = FALSE;
                break;
            }
        }
    } else {
        status = FALSE;
    }
#endif  ///GATTS_INCLUDED == TRUE
    return status;
}

/*******************************************************************************
**
** Function         gatt_sr_is_prep_cnt_zero
**
** Description      Check the prepare write request count is zero or not
**
** Returns          True no prepare write request
**
*******************************************************************************/
BOOLEAN gatt_sr_is_prep_cnt_zero(tGATT_TCB *p_tcb)
{
    BOOLEAN status = TRUE;
    UINT8   i;

    if (p_tcb) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            if (p_tcb->prep_cnt[i]) {
                status = FALSE;
                break;
            }
        }
    } else {
        status = FALSE;
    }
    return status;
}


/*******************************************************************************
**
** Function         gatt_sr_reset_cback_cnt
**
** Description      Reset the application callback count to zero
**
** Returns         None
**
*******************************************************************************/
void gatt_sr_reset_cback_cnt(tGATT_TCB *p_tcb )
{
#if (GATTS_INCLUDED == TRUE)
    UINT8 i;

    if (p_tcb) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            p_tcb->sr_cmd.cback_cnt[i] = 0;
        }
    }
#endif  ///GATTS_INCLUDED == TRUE
}

/*******************************************************************************
**
** Function         gatt_sr_reset_prep_cnt
**
** Description     Reset the prep write count to zero
**
** Returns        None
**
*******************************************************************************/
void gatt_sr_reset_prep_cnt(tGATT_TCB *p_tcb )
{
    UINT8 i;
    if (p_tcb) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            p_tcb->prep_cnt[i] = 0;
        }
    }
}


/*******************************************************************************
**
** Function         gatt_sr_update_cback_cnt
**
** Description    Update the teh applicaiton callback count
**
** Returns           None
**
*******************************************************************************/
void gatt_sr_update_cback_cnt(tGATT_TCB *p_tcb, tGATT_IF gatt_if, BOOLEAN is_inc, BOOLEAN is_reset_first)
{
#if (GATTS_INCLUDED == TRUE)
    UINT8 idx = ((UINT8) gatt_if) - 1 ;

    if (p_tcb) {
        if (is_reset_first) {
            gatt_sr_reset_cback_cnt(p_tcb);
        }
        if (is_inc) {
            p_tcb->sr_cmd.cback_cnt[idx]++;
        } else {
            if ( p_tcb->sr_cmd.cback_cnt[idx]) {
                p_tcb->sr_cmd.cback_cnt[idx]--;
            }
        }
    }
#endif  ///GATTS_INCLUDED == TRUE
}


/*******************************************************************************
**
** Function         gatt_sr_update_prep_cnt
**
** Description    Update the teh prepare write request count
**
** Returns           None
**
*******************************************************************************/
void gatt_sr_update_prep_cnt(tGATT_TCB *p_tcb, tGATT_IF gatt_if, BOOLEAN is_inc, BOOLEAN is_reset_first)
{
    UINT8 idx = ((UINT8) gatt_if) - 1 ;

    GATT_TRACE_DEBUG("gatt_sr_update_prep_cnt tcb idx=%d gatt_if=%d is_inc=%d is_reset_first=%d",
                     p_tcb->tcb_idx, gatt_if, is_inc, is_reset_first);

    if (p_tcb) {
        if (is_reset_first) {
            gatt_sr_reset_prep_cnt(p_tcb);
        }
        if (is_inc) {
            p_tcb->prep_cnt[idx]++;
        } else {
            if (p_tcb->prep_cnt[idx]) {
                p_tcb->prep_cnt[idx]--;
            }
        }
    }
}
/*******************************************************************************
**
** Function         gatt_cancel_open
**
** Description      Cancel open request
**
** Returns         Boolean
**
*******************************************************************************/
BOOLEAN gatt_cancel_open(tGATT_IF gatt_if, BD_ADDR bda)
{
    tGATT_TCB *p_tcb = NULL;
    BOOLEAN status = TRUE;

    p_tcb = gatt_find_tcb_by_addr(bda, BT_TRANSPORT_LE);

    if (p_tcb) {
        if (gatt_get_ch_state(p_tcb) == GATT_CH_OPEN) {
            GATT_TRACE_ERROR("GATT_CancelConnect - link connected Too late to cancel");
            status = FALSE;
        } else {
            gatt_update_app_use_link_flag(gatt_if, p_tcb, FALSE, FALSE);
            if (!gatt_num_apps_hold_link(p_tcb)) {
                gatt_disconnect(p_tcb);
            }
        }
    }

    return status;
}

/*******************************************************************************
**
** Function         gatt_find_app_hold_link
**
** Description      find the applicaiton that is holding the specified link
**
** Returns         Boolean
**
*******************************************************************************/
BOOLEAN gatt_find_app_hold_link(tGATT_TCB *p_tcb, UINT8 start_idx, UINT8 *p_found_idx, tGATT_IF *p_gatt_if)
{
    UINT8 i;
    BOOLEAN found = FALSE;

    for (i = start_idx; i < GATT_MAX_APPS; i ++) {
        if (p_tcb->app_hold_link[i]) {
            *p_gatt_if = gatt_cb.clcb[i].p_reg->gatt_if;
            *p_found_idx = i;
            found = TRUE;
            break;
        }
    }
    return found;
}

/*******************************************************************************
**
** Function         gatt_cmd_enq
**
** Description      Enqueue this command.
**
** Returns          None.
**
*******************************************************************************/
BOOLEAN gatt_cmd_enq(tGATT_TCB *p_tcb, UINT16 clcb_idx, BOOLEAN to_send, UINT8 op_code, BT_HDR *p_buf)
{
    tGATT_CMD_Q  *p_cmd = &p_tcb->cl_cmd_q[p_tcb->next_slot_inq];

    p_cmd->to_send = to_send; /* waiting to be sent */
    p_cmd->op_code  = op_code;
    p_cmd->p_cmd    = p_buf;
    p_cmd->clcb_idx = clcb_idx;

    if (!to_send) {
        p_tcb->pending_cl_req = p_tcb->next_slot_inq;
    }

    p_tcb->next_slot_inq ++;
    p_tcb->next_slot_inq %= GATT_CL_MAX_LCB;

    return TRUE;
}

/*******************************************************************************
**
** Function         gatt_cmd_dequeue
**
** Description      dequeue the command in the client CCB command queue.
**
** Returns          total number of clcb found.
**
*******************************************************************************/
tGATT_CLCB *gatt_cmd_dequeue(tGATT_TCB *p_tcb, UINT8 *p_op_code)
{
    tGATT_CMD_Q  *p_cmd = &p_tcb->cl_cmd_q[p_tcb->pending_cl_req];
    tGATT_CLCB *p_clcb = NULL;

    if (p_tcb->pending_cl_req != p_tcb->next_slot_inq) {
        p_clcb = &gatt_cb.clcb[p_cmd->clcb_idx];

        *p_op_code = p_cmd->op_code;

        p_tcb->pending_cl_req ++;
        p_tcb->pending_cl_req %= GATT_CL_MAX_LCB;
    }

    return p_clcb;
}

/*******************************************************************************
**
** Function         gatt_send_write_msg
**
** Description      This real function send out the ATT message for write.
**
** Returns          status code
**
*******************************************************************************/
UINT8 gatt_send_write_msg (tGATT_TCB *p_tcb, UINT16 clcb_idx, UINT8 op_code,
                           UINT16 handle, UINT16 len,
                           UINT16 offset, UINT8 *p_data)
{
    tGATT_CL_MSG     msg;

    msg.attr_value.handle = handle;
    msg.attr_value.len = len;
    msg.attr_value.offset = offset;

    memcpy (msg.attr_value.value, p_data, len);

    /* write by handle */
    return attp_send_cl_msg(p_tcb, clcb_idx, op_code, &msg);
}

/*******************************************************************************
**
** Function         gatt_act_send_browse
**
** Description      This function ends a browse command request, including read
**                  information request and read by type request.
**
** Returns          status code
**
*******************************************************************************/
UINT8 gatt_act_send_browse(tGATT_TCB *p_tcb, UINT16 index, UINT8 op, UINT16 s_handle,
                           UINT16 e_handle, tBT_UUID uuid)
{
    tGATT_CL_MSG     msg;

    msg.browse.s_handle = s_handle;
    msg.browse.e_handle   = e_handle;
    memcpy(&msg.browse.uuid, &uuid, sizeof(tBT_UUID));

    /* write by handle */
    return attp_send_cl_msg(p_tcb, index, op, &msg);
}

/*******************************************************************************
**
** Function         gatt_end_operation
**
** Description      This function ends a discovery, send callback and finalize
**                  some control value.
**
** Returns          16 bits uuid.
**
*******************************************************************************/
void gatt_end_operation(tGATT_CLCB *p_clcb, tGATT_STATUS status, void *p_data)
{
    tGATT_CL_COMPLETE   cb_data;
    tGATT_CMPL_CBACK    *p_cmpl_cb = (p_clcb->p_reg) ? p_clcb->p_reg->app_cb.p_cmpl_cb : NULL;
    UINT8               op = p_clcb->operation, disc_type = GATT_DISC_MAX;
    tGATT_DISC_CMPL_CB  *p_disc_cmpl_cb = (p_clcb->p_reg) ? p_clcb->p_reg->app_cb.p_disc_cmpl_cb : NULL;
    UINT16              conn_id;
    UINT8               operation;

    GATT_TRACE_DEBUG ("gatt_end_operation status=%d op=%d subtype=%d",
                      status, p_clcb->operation, p_clcb->op_subtype);
    memset(&cb_data.att_value, 0, sizeof(tGATT_VALUE));

    if (p_cmpl_cb != NULL && p_clcb->operation != 0) {
        if (p_clcb->operation == GATTC_OPTYPE_READ) {
            cb_data.att_value.handle   = p_clcb->s_handle;
            cb_data.att_value.len      = p_clcb->counter;

            if (p_data && p_clcb->counter) {
                memcpy (cb_data.att_value.value, p_data, cb_data.att_value.len);
            }
        }

        if (p_clcb->operation == GATTC_OPTYPE_WRITE) {
            memset(&cb_data.att_value, 0, sizeof(tGATT_VALUE));
            cb_data.handle           =
                cb_data.att_value.handle = p_clcb->s_handle;
            if (p_clcb->op_subtype == GATT_WRITE_PREPARE) {
                if (p_data) {
                    cb_data.att_value = *((tGATT_VALUE *) p_data);
                } else {
                    GATT_TRACE_DEBUG("Rcv Prepare write rsp but no data");
                }
            }
        }

        if (p_clcb->operation == GATTC_OPTYPE_CONFIG) {
            cb_data.mtu = p_clcb->p_tcb->payload_size;
        }

        if (p_clcb->operation == GATTC_OPTYPE_DISCOVERY) {
            disc_type = p_clcb->op_subtype;
        }
    }

    if (p_clcb->p_attr_buf) {
        osi_free(p_clcb->p_attr_buf);
    }

    operation =  p_clcb->operation;
    conn_id = p_clcb->conn_id;
    btu_stop_timer(&p_clcb->rsp_timer_ent);

    gatt_clcb_dealloc(p_clcb);

    if (p_disc_cmpl_cb && (op == GATTC_OPTYPE_DISCOVERY)) {
        (*p_disc_cmpl_cb)(conn_id, disc_type, status);
    } else if (p_cmpl_cb && op) {
        (*p_cmpl_cb)(conn_id, op, status, &cb_data);
    } else
        GATT_TRACE_WARNING ("gatt_end_operation not sent out op=%d p_disc_cmpl_cb:%p p_cmpl_cb:%p",
                            operation, p_disc_cmpl_cb, p_cmpl_cb);
}

/*******************************************************************************
**
** Function         gatt_cleanup_upon_disc
**
** Description      This function cleans up the control blocks when L2CAP channel
**                  disconnect.
**
** Returns          16 bits uuid.
**
*******************************************************************************/
void gatt_cleanup_upon_disc(BD_ADDR bda, UINT16 reason, tBT_TRANSPORT transport)
{
    tGATT_TCB       *p_tcb = NULL;
    tGATT_CLCB      *p_clcb;
    UINT8           i;
    UINT16          conn_id;
    tGATT_REG        *p_reg = NULL;


    GATT_TRACE_DEBUG ("gatt_cleanup_upon_disc ");

    if ((p_tcb = gatt_find_tcb_by_addr(bda, transport)) != NULL) {
        GATT_TRACE_DEBUG ("found p_tcb ");
        gatt_set_ch_state(p_tcb, GATT_CH_CLOSE);
        for (i = 0; i < GATT_CL_MAX_LCB; i ++) {
            p_clcb = &gatt_cb.clcb[i];
            if (p_clcb->in_use && p_clcb->p_tcb == p_tcb) {
                btu_stop_timer(&p_clcb->rsp_timer_ent);
                GATT_TRACE_DEBUG ("found p_clcb conn_id=%d clcb_idx=%d", p_clcb->conn_id, p_clcb->clcb_idx);
                if (p_clcb->operation != GATTC_OPTYPE_NONE) {
                    gatt_end_operation(p_clcb, GATT_ERROR, NULL);
                }

                gatt_clcb_dealloc(p_clcb);

            }
        }

        btu_stop_timer (&p_tcb->ind_ack_timer_ent);
        btu_stop_timer (&p_tcb->conf_timer_ent);
        gatt_free_pending_ind(p_tcb);
        gatt_free_pending_enc_queue(p_tcb);
        gatt_free_pending_prepare_write_queue(p_tcb);
#if (GATTS_INCLUDED == TRUE)
        fixed_queue_free(p_tcb->sr_cmd.multi_rsp_q, osi_free_func);
        p_tcb->sr_cmd.multi_rsp_q = NULL;
#endif  ///GATTS_INCLUDED == TRUE
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            p_reg = &gatt_cb.cl_rcb[i];
            if (p_reg->in_use && p_reg->app_cb.p_conn_cb) {
                conn_id = GATT_CREATE_CONN_ID(p_tcb->tcb_idx, p_reg->gatt_if);
                GATT_TRACE_DEBUG ("found p_reg tcb_idx=%d gatt_if=%d  conn_id=0x%x", p_tcb->tcb_idx, p_reg->gatt_if, conn_id);
                (*p_reg->app_cb.p_conn_cb)(p_reg->gatt_if,  bda, conn_id, FALSE, reason, transport);
            }
        }
        memset(p_tcb, 0, sizeof(tGATT_TCB));

    } else {
        GATT_TRACE_DEBUG ("exit gatt_cleanup_upon_disc ");
        BTM_Recovery_Pre_State();
    }
}
/*******************************************************************************
**
** Function         gatt_dbg_req_op_name
**
** Description      Get op code description name, for debug information.
**
** Returns          UINT8 *: name of the operation.
**
*******************************************************************************/
UINT8 *gatt_dbg_op_name(UINT8 op_code)
{
    UINT8 pseduo_op_code_idx = op_code & (~GATT_WRITE_CMD_MASK);

    if (op_code == GATT_CMD_WRITE ) {
        pseduo_op_code_idx = 0x14; /* just an index to op_code_name */

    }

    if (op_code == GATT_SIGN_CMD_WRITE) {
        pseduo_op_code_idx = 0x15; /* just an index to op_code_name */
    }

    if (pseduo_op_code_idx <= GATT_OP_CODE_MAX) {
        return (UINT8 *) op_code_name[pseduo_op_code_idx];
    } else {
        return (UINT8 *)"Op Code Exceed Max";
    }
}

/*******************************************************************************
**
** Function         gatt_dbg_display_uuid
**
** Description      Disaplay the UUID
**
** Returns          None
**
*******************************************************************************/
void gatt_dbg_display_uuid(tBT_UUID bt_uuid)
{
    char str_buf[50];
    int x = 0;

    if (bt_uuid.len == LEN_UUID_16) {
        sprintf(str_buf, "0x%04x", bt_uuid.uu.uuid16);
    } else if (bt_uuid.len == LEN_UUID_32) {
        sprintf(str_buf, "0x%08x", (unsigned int)bt_uuid.uu.uuid32);
    } else if (bt_uuid.len == LEN_UUID_128) {
        x += sprintf(&str_buf[x], "0x%02x%02x%02x%02x%02x%02x%02x%02x",
                     bt_uuid.uu.uuid128[15], bt_uuid.uu.uuid128[14],
                     bt_uuid.uu.uuid128[13], bt_uuid.uu.uuid128[12],
                     bt_uuid.uu.uuid128[11], bt_uuid.uu.uuid128[10],
                     bt_uuid.uu.uuid128[9], bt_uuid.uu.uuid128[8]);
        sprintf(&str_buf[x], "%02x%02x%02x%02x%02x%02x%02x%02x",
                bt_uuid.uu.uuid128[7], bt_uuid.uu.uuid128[6],
                bt_uuid.uu.uuid128[5], bt_uuid.uu.uuid128[4],
                bt_uuid.uu.uuid128[3], bt_uuid.uu.uuid128[2],
                bt_uuid.uu.uuid128[1], bt_uuid.uu.uuid128[0]);
    } else {
        BCM_STRNCPY_S(str_buf, sizeof(str_buf), "Unknown UUID 0", 15);
    }

    GATT_TRACE_DEBUG ("UUID=[%s]", str_buf);

}


/*******************************************************************************
**
** Function         gatt_is_bg_dev_for_app
**
** Description      find is this one of the background devices for the application
**
** Returns          TRUE this is one of the background devices for the  application
**
*******************************************************************************/
BOOLEAN gatt_is_bg_dev_for_app(tGATT_BG_CONN_DEV *p_dev, tGATT_IF gatt_if)
{
    UINT8   i;

    for (i = 0; i < GATT_MAX_APPS; i ++ ) {
        if (p_dev->in_use && (p_dev->gatt_if[i] == gatt_if)) {
            return TRUE;
        }
    }
    return FALSE;
}
/*******************************************************************************
**
** Function         gatt_find_bg_dev
**
** Description      find background connection device from the list.
**
** Returns          pointer to the device record
**
*******************************************************************************/
tGATT_BG_CONN_DEV *gatt_find_bg_dev(BD_ADDR remote_bda)
{
    tGATT_BG_CONN_DEV    *p_dev_list = &gatt_cb.bgconn_dev[0];
    UINT8   i;

    for (i = 0; i < GATT_MAX_BG_CONN_DEV; i ++, p_dev_list ++) {
        if (p_dev_list->in_use && !memcmp(p_dev_list->remote_bda, remote_bda, BD_ADDR_LEN)) {
            return p_dev_list;
        }
    }
    return NULL;
}
/*******************************************************************************
**
** Function         gatt_alloc_bg_dev
**
** Description      allocate a background connection device record
**
** Returns          pointer to the device record
**
*******************************************************************************/
tGATT_BG_CONN_DEV *gatt_alloc_bg_dev(BD_ADDR remote_bda)
{
    tGATT_BG_CONN_DEV    *p_dev_list = &gatt_cb.bgconn_dev[0];
    UINT8   i;

    for (i = 0; i < GATT_MAX_BG_CONN_DEV; i ++, p_dev_list ++) {
        if (!p_dev_list->in_use) {
            p_dev_list->in_use = TRUE;
            memcpy(p_dev_list->remote_bda, remote_bda, BD_ADDR_LEN);

            return p_dev_list;
        }
    }
    return NULL;
}

/*******************************************************************************
**
** Function         gatt_add_bg_dev_list
**
** Description      add/remove device from the back ground connection device list
**
** Returns          TRUE if device added to the list; FALSE failed
**
*******************************************************************************/
BOOLEAN gatt_add_bg_dev_list(tGATT_REG *p_reg,  BD_ADDR bd_addr, BOOLEAN is_initator)
{
    tGATT_IF gatt_if =  p_reg->gatt_if;
    tGATT_BG_CONN_DEV   *p_dev = NULL;
    UINT8       i;
    BOOLEAN      ret = FALSE;

    if ((p_dev = gatt_find_bg_dev(bd_addr)) == NULL) {
        p_dev = gatt_alloc_bg_dev(bd_addr);
    }

    if (p_dev) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            if (is_initator) {
                if (p_dev->gatt_if[i] == gatt_if) {
                    GATT_TRACE_ERROR("device already in iniator white list");
                    return TRUE;
                } else if (p_dev->gatt_if[i] == 0) {
                    p_dev->gatt_if[i] = gatt_if;
                    if (i == 0) {
                        ret = BTM_BleUpdateBgConnDev(TRUE, bd_addr);
                    } else {
                        ret = TRUE;
                    }
                    break;
                }
            } else {
                if (p_dev->listen_gif[i] == gatt_if) {
                    GATT_TRACE_ERROR("device already in adv white list");
                    return TRUE;
                } else if (p_dev->listen_gif[i] == 0) {
                    if (p_reg->listening == GATT_LISTEN_TO_ALL) {
                        p_reg->listening = GATT_LISTEN_TO_NONE;
                    }

                    p_reg->listening ++;
                    p_dev->listen_gif[i] = gatt_if;

                    if (i == 0) {
                        ret = BTM_BleUpdateAdvWhitelist(TRUE, bd_addr);
                    } else {
                        ret = TRUE;
                    }
                    break;
                }
            }
        }
    } else {
        GATT_TRACE_ERROR("no device record available");
    }

    return ret;
}

/*******************************************************************************
**
** Function         gatt_remove_bg_dev_for_app
**
** Description      Remove the application interface for the specified background device
**
** Returns          Boolean
**
*******************************************************************************/
BOOLEAN gatt_remove_bg_dev_for_app(tGATT_IF gatt_if, BD_ADDR bd_addr)
{
    tGATT_TCB    *p_tcb = gatt_find_tcb_by_addr(bd_addr, BT_TRANSPORT_LE);
    BOOLEAN       status;

    if (p_tcb) {
        gatt_update_app_use_link_flag(gatt_if, p_tcb, FALSE, FALSE);
    }
    status = gatt_update_auto_connect_dev(gatt_if, FALSE, bd_addr, TRUE);
    return status;
}


/*******************************************************************************
**
** Function         gatt_get_num_apps_for_bg_dev
**
** Description      Gte the number of applciations for the specified background device
**
** Returns          UINT8 total number fo applications
**
*******************************************************************************/
UINT8 gatt_get_num_apps_for_bg_dev(BD_ADDR bd_addr)
{
    tGATT_BG_CONN_DEV   *p_dev = NULL;
    UINT8   i;
    UINT8   cnt = 0;

    if ((p_dev = gatt_find_bg_dev(bd_addr)) != NULL) {
        for (i = 0; i < GATT_MAX_APPS; i ++) {
            if (p_dev->gatt_if[i]) {
                cnt++;
            }
        }
    }
    return cnt;
}

/*******************************************************************************
**
** Function         gatt_find_app_for_bg_dev
**
** Description      find the application interface for the specified background device
**
** Returns          Boolean
**
*******************************************************************************/
BOOLEAN gatt_find_app_for_bg_dev(BD_ADDR bd_addr, tGATT_IF *p_gatt_if)
{
    tGATT_BG_CONN_DEV   *p_dev = NULL;
    UINT8   i;
    BOOLEAN ret = FALSE;

    if ((p_dev = gatt_find_bg_dev(bd_addr)) == NULL) {
        return ret;
    }

    for (i = 0; i < GATT_MAX_APPS; i ++) {
        if (p_dev->gatt_if[i] != 0 ) {
            *p_gatt_if = p_dev->gatt_if[i];
            ret = TRUE;
            break;
        }
    }
    return ret;
}


/*******************************************************************************
**
** Function         gatt_remove_bg_dev_from_list
**
** Description      add/remove device from the back ground connection device list or
**                  listening to advertising list.
**
** Returns          pointer to the device record
**
*******************************************************************************/
BOOLEAN gatt_remove_bg_dev_from_list(tGATT_REG *p_reg, BD_ADDR bd_addr, BOOLEAN is_initiator)
{
    tGATT_IF gatt_if = p_reg->gatt_if;
    tGATT_BG_CONN_DEV   *p_dev = NULL;
    UINT8   i, j;
    BOOLEAN ret = FALSE;

    if ((p_dev = gatt_find_bg_dev(bd_addr)) == NULL) {
        return ret;
    }

    for (i = 0; i < GATT_MAX_APPS && (p_dev->gatt_if[i] > 0 || p_dev->listen_gif[i]); i ++) {
        if (is_initiator) {
            if (p_dev->gatt_if[i] == gatt_if) {
                p_dev->gatt_if[i] = 0;
                /* move all element behind one forward */
                for (j = i + 1; j < GATT_MAX_APPS; j ++) {
                    p_dev->gatt_if[j - 1] = p_dev->gatt_if[j];
                }

                if (p_dev->gatt_if[0] == 0) {
                    ret = BTM_BleUpdateBgConnDev(FALSE, p_dev->remote_bda);
                } else {
                    ret = TRUE;
                }

                break;
            }
        } else {
            if (p_dev->listen_gif[i] == gatt_if) {
                p_dev->listen_gif[i] = 0;
                p_reg->listening --;
                /* move all element behind one forward */
                for (j = i + 1; j < GATT_MAX_APPS; j ++) {
                    p_dev->listen_gif[j - 1] = p_dev->listen_gif[j];
                }

                if (p_dev->listen_gif[0] == 0) {
                    ret = BTM_BleUpdateAdvWhitelist(FALSE, p_dev->remote_bda);
                } else {
                    ret = TRUE;
                }
                break;
            }
        }
    }

    if (i != GATT_MAX_APPS && p_dev->gatt_if[0] == 0 && p_dev->listen_gif[0] == 0) {
        memset(p_dev, 0, sizeof(tGATT_BG_CONN_DEV));
    }

    return ret;
}
/*******************************************************************************
**
** Function         gatt_deregister_bgdev_list
**
** Description      deregister all related back ground connetion device.
**
** Returns          pointer to the device record
**
*******************************************************************************/
void gatt_deregister_bgdev_list(tGATT_IF gatt_if)
{
    tGATT_BG_CONN_DEV    *p_dev_list = &gatt_cb.bgconn_dev[0];
    UINT8 i , j, k;
    tGATT_REG       *p_reg = gatt_get_regcb(gatt_if);

    /* update the BG conn device list */
    for (i = 0 ; i < GATT_MAX_BG_CONN_DEV; i ++, p_dev_list ++ ) {
        if (p_dev_list->in_use) {
            for (j = 0; j < GATT_MAX_APPS; j ++) {
                if (p_dev_list->gatt_if[j] == 0 && p_dev_list->listen_gif[j] == 0) {
                    break;
                }

                if (p_dev_list->gatt_if[j] == gatt_if) {
                    for (k = j + 1; k < GATT_MAX_APPS; k ++) {
                        p_dev_list->gatt_if[k - 1] = p_dev_list->gatt_if[k];
                    }

                    if (p_dev_list->gatt_if[0] == 0) {
                        BTM_BleUpdateBgConnDev(FALSE, p_dev_list->remote_bda);
                    }
                }

                if (p_dev_list->listen_gif[j] == gatt_if) {
                    p_dev_list->listen_gif[j] = 0;

                    if (p_reg != NULL && p_reg->listening > 0) {
                        p_reg->listening --;
                    }

                    /* move all element behind one forward */
                    for (k = j + 1; k < GATT_MAX_APPS; k ++) {
                        p_dev_list->listen_gif[k - 1] = p_dev_list->listen_gif[k];
                    }

                    if (p_dev_list->listen_gif[0] == 0) {
                        BTM_BleUpdateAdvWhitelist(FALSE, p_dev_list->remote_bda);
                    }
                }
            }
        }
    }
}


/*******************************************************************************
**
** Function         gatt_reset_bgdev_list
**
** Description      reset bg device list
**
** Returns          pointer to the device record
**
*******************************************************************************/
void gatt_reset_bgdev_list(void)
{
    memset(&gatt_cb.bgconn_dev, 0 , sizeof(tGATT_BG_CONN_DEV)*GATT_MAX_BG_CONN_DEV);

}
/*******************************************************************************
**
** Function         gatt_update_auto_connect_dev
**
** Description      This function add or remove a device for background connection
**                  procedure.
**
** Parameters       gatt_if: Application ID.
**                  add: add peer device
**                  bd_addr: peer device address.
**
** Returns          TRUE if connection started; FALSE if connection start failure.
**
*******************************************************************************/
BOOLEAN gatt_update_auto_connect_dev (tGATT_IF gatt_if, BOOLEAN add, BD_ADDR bd_addr, BOOLEAN is_initator)
{
    BOOLEAN         ret = FALSE;
    tGATT_REG        *p_reg;
    tGATT_TCB       *p_tcb = gatt_find_tcb_by_addr(bd_addr, BT_TRANSPORT_LE);

    GATT_TRACE_API ("gatt_update_auto_connect_dev ");
    /* Make sure app is registered */
    if ((p_reg = gatt_get_regcb(gatt_if)) == NULL) {
        GATT_TRACE_ERROR("gatt_update_auto_connect_dev - gatt_if %d is not registered", gatt_if);
        return (FALSE);
    }

    if (add) {
        ret = gatt_add_bg_dev_list(p_reg, bd_addr, is_initator);

        if (ret && p_tcb != NULL) {
            /* if a connected device, update the link holding number */
            gatt_update_app_use_link_flag(gatt_if, p_tcb, TRUE, TRUE);
        }
    } else {
        ret = gatt_remove_bg_dev_from_list(p_reg, bd_addr, is_initator);
    }
    return ret;
}



/*******************************************************************************
**
** Function     gatt_add_pending_new_srv_start
**
** Description  Add a pending new srv start to the new service start queue
**
** Returns    Pointer to the new service start buffer, NULL no buffer available
**
*******************************************************************************/
tGATT_PENDING_ENC_CLCB *gatt_add_pending_enc_channel_clcb(tGATT_TCB *p_tcb, tGATT_CLCB *p_clcb )
{
    tGATT_PENDING_ENC_CLCB   *p_buf;

    GATT_TRACE_DEBUG ("gatt_add_pending_new_srv_start");
    if ((p_buf = (tGATT_PENDING_ENC_CLCB *)osi_malloc((UINT16)sizeof(tGATT_PENDING_ENC_CLCB))) != NULL) {
        GATT_TRACE_DEBUG ("enqueue a new pending encryption channel clcb");
        p_buf->p_clcb = p_clcb;
    fixed_queue_enqueue(p_tcb->pending_enc_clcb, p_buf);
    }
    return p_buf;
}
/*******************************************************************************
**
** Function     gatt_update_listen_mode
**
** Description  update peripheral role listening mode
**
** Returns    Pointer to the new service start buffer, NULL no buffer available
**
*******************************************************************************/
BOOLEAN gatt_update_listen_mode(void)
{
    UINT8           ii = 0;
    tGATT_REG       *p_reg = &gatt_cb.cl_rcb[0];
    UINT8           listening = 0;
    UINT16          connectability, window, interval;
    BOOLEAN         rt = TRUE;

    for (; ii < GATT_MAX_APPS; ii ++, p_reg ++) {
        if ( p_reg->in_use && p_reg->listening > listening) {
            listening = p_reg->listening;
        }
    }

    if (listening == GATT_LISTEN_TO_ALL ||
            listening == GATT_LISTEN_TO_NONE) {
        BTM_BleUpdateAdvFilterPolicy (AP_SCAN_CONN_ALL);
    } else {
        BTM_BleUpdateAdvFilterPolicy (AP_SCAN_CONN_WL);
    }

    if (rt) {
        connectability = BTM_ReadConnectability (&window, &interval);

        if (listening != GATT_LISTEN_TO_NONE) {
            connectability |= BTM_BLE_CONNECTABLE;
        } else {
            if ((connectability & BTM_BLE_CONNECTABLE) == 0) {
                connectability &= ~BTM_BLE_CONNECTABLE;
            }
        }
        /* turning on the adv now */
        btm_ble_set_connectability(connectability);
    }

    return rt;

}
#endif