Improve BT HAL write response to BT server reads

#define SOCK_SEND_TIMEOUT_MS 2000  /* Timeout for sending */

#define SOCK_RECV_TIMEOUT_MS 5000  /* Timeout for receiving */

// set WRITE_POLL_MS to 0 for blocking sockets, nonzero for polled non-blocking sockets

#define WRITE_POLL_MS 20

#define CASE_RETURN_STR(const) case const: return #const;

#define FNLOG()             LOG_VERBOSE(LOG_TAG, "%s", __FUNCTION__);

#define DEBUG(fmt, ...)     LOG_VERBOSE(LOG_TAG, "%s: " fmt,__FUNCTION__, ## __VA_ARGS__)

#define INFO(fmt, ...)      LOG_INFO(LOG_TAG, "%s: " fmt,__FUNCTION__, ## __VA_ARGS__)

#define WARN(fmt, ...)      LOG_WARN(LOG_TAG, "%s: " fmt,__FUNCTION__, ## __VA_ARGS__)

#define ERROR(fmt, ...)     LOG_ERROR(LOG_TAG, "%s: " fmt,__FUNCTION__, ## __VA_ARGS__)

#define ASSERTC(cond, msg, val) if (!(cond)) {ERROR("### ASSERT : %s line %d %s (%d) ###", __FILE__, __LINE__, msg, val);}

static int skt_write(int fd, const void *p, size_t len)

{

    ssize_t sent;

    FNLOG();

    ts_log("skt_write", len, NULL);

    if (WRITE_POLL_MS == 0) {

        // do not poll, use blocking send

        OSI_NO_INTR(sent = send(fd, p, len, MSG_NOSIGNAL));

        if (sent == -1)

        ERROR("write failed with errno=%d\n", errno);

            ERROR("write failed with error(%s)", strerror(errno));

        return (int)sent;

    }

    // use non-blocking send, poll

    int ms_timeout = SOCK_SEND_TIMEOUT_MS;

    size_t count = 0;

    while (count < len) {

        OSI_NO_INTR(sent = send(fd, p, len - count, MSG_NOSIGNAL | MSG_DONTWAIT));

        if (sent == -1) {

            if (errno != EAGAIN && errno != EWOULDBLOCK) {

                ERROR("write failed with error(%s)", strerror(errno));

                return -1;

            }

            if (ms_timeout >= WRITE_POLL_MS) {

                usleep(WRITE_POLL_MS * 1000);

                ms_timeout -= WRITE_POLL_MS;

                continue;

            }

            WARN("write timeout exceeded, sent %zu bytes", count);

            return -1;

        }

        count += sent;

        p = (const uint8_t *)p + sent;

    }

    return (int)count;

}

static int skt_disconnect(int fd)

{

    INFO("fd %d", fd);