void
AsyncIoThread::run()
{
  bool first_flag = true;
  Request *request;
  NDB_TICKS last_yield_ticks;

  // Create theMemoryChannel in the thread that will wait for it
  NdbMutex_Lock(theStartMutexPtr);
  theStartFlag = true;
  NdbMutex_Unlock(theStartMutexPtr);
  NdbCondition_Signal(theStartConditionPtr);

  EmulatedJamBuffer jamBuffer;
  jamBuffer.theEmulatedJamIndex = 0;
  // This key is needed by jamNoBlock().
  NdbThread_SetTlsKey(NDB_THREAD_TLS_JAM, &jamBuffer);

  while (1)
  {
    if (m_real_time)
    {
      /**
       * If we are running in real-time we'll simply insert a break every
       * so often to ensure that low-prio threads aren't blocked from the
       * CPU, this is especially important if we're using a compressed
       * file system where lots of CPU is used by this thread.
       */
      bool yield_flag = false;
      const NDB_TICKS current_ticks = NdbTick_getCurrentTicks();

      if (first_flag)
      {
        first_flag = false;
        yield_flag = true;
      }
      else
      {
        Uint64 micros_passed =
          NdbTick_Elapsed(last_yield_ticks, current_ticks).microSec();
        if (micros_passed > 10000)
        {
          yield_flag = true;
        }
      }
      if (yield_flag)
      {
        if (NdbThread_yield_rt(theThreadPtr, TRUE))
        {
          m_real_time = false;
        }
        last_yield_ticks = current_ticks;
      }
    }
    request = theMemoryChannelPtr->readChannel();
    if (!request || request->action == Request::end)
    {
      DEBUG(ndbout_c("Nothing read from Memory Channel in AsyncFile"));
      theStartFlag = false;
      return;
    }//if

    AsyncFile * file = request->file;
    m_current_request= request;
    switch (request->action) {
    case Request::open:
      file->openReq(request);
      if (request->error == 0 && request->m_do_bind)
        attach(file);
      break;
    case Request::close:
      file->closeReq(request);
      detach(file);
      break;
    case Request::closeRemove:
      file->closeReq(request);
      file->removeReq(request);
      detach(file);
      break;
    case Request::readPartial:
    case Request::read:
      file->readReq(request);
      break;
    case Request::readv:
      file->readvReq(request);
      break;
    case Request::write:
      file->writeReq(request);
      break;
    case Request::writev:
      file->writevReq(request);
      break;
    case Request::writeSync:
      file->writeReq(request);
      file->syncReq(request);
      break;
    case Request::writevSync:
      file->writevReq(request);
      file->syncReq(request);
      break;
//.........这里部分代码省略.........

QT_BEGIN_NAMESPACE

/*****************************************************************************
  Q3CString member functions
 *****************************************************************************/

/*!
    \class Q3CString
    \reentrant
    \brief The Q3CString class provides an abstraction of the classic C
    zero-terminated char array (char *).

    \compat

    Q3CString tries to behave like a more convenient \c{const char *}.
    The price of doing this is that some algorithms will perform
    badly. For example, append() is O(length()) since it scans for a
    null terminator. Although you might use Q3CString for text that is
    never exposed to the user, for most purposes, and especially for
    user-visible text, you should use QString. QString provides
    implicit sharing, Unicode and other internationalization support,
    and is well optimized.

    Note that for the Q3CString methods that take a \c{const char *}
    parameter the \c{const char *} must either be 0 (null) or not-null
    and '\0' (NUL byte) terminated; otherwise the results are
    undefined.

    A default constructed Q3CString is \e null, i.e. both the length
    and the data pointer are 0 and isNull() returns true.
    
    \note However, if you ask for the data pointer of a null Q3CString
    by calling data(), then because the internal representation of the
    null Q3CString is shared, it will be detached and replaced with a
    non-shared, empty representation, a non-null data pointer will be
    returned, and subsequent calls to isNull() will return false. But
    if you ask for the data pointer of a null Q3CString by calling
    constData(), the shared internal representation is not detached, a
    null data pointer is returned, and subsequent calls to isNull()
    will continue to return true.

    A Q3CString that references the empty string ("", a single '\0'
    char) is \e empty, i.e. isEmpty() returns true.  Both null and
    empty Q3CStrings are legal parameters to the methods.  Assigning
    \c{const char *} 0 to Q3CString produces a null Q3CString.

    The length() function returns the length of the string; resize()
    resizes the string and truncate() truncates the string. A string
    can be filled with a character using fill(). Strings can be left
    or right padded with characters using leftJustify() and
    rightJustify(). Characters, strings and regular expressions can be
    searched for using find() and findRev(), and counted using
    contains().

    Strings and characters can be inserted with insert() and appended
    with append(). A string can be prepended with prepend().
    Characters can be removed from the string with remove() and
    replaced with replace().

    Portions of a string can be extracted using left(), right() and
    mid(). Whitespace can be removed using stripWhiteSpace() and
    simplifyWhiteSpace(). Strings can be converted to uppercase or
    lowercase with upper() and lower() respectively.

    Strings that contain numbers can be converted to numbers with
    toShort(), toInt(), toLong(), toULong(), toFloat() and toDouble().
    Numbers can be converted to strings with setNum().

    Many operators are overloaded to work with Q3CStrings. Q3CString
    also supports some more obscure functions, e.g. sprintf(),
    setStr() and setExpand().

    \sidebar Note on Character Comparisons

    In Q3CString the notion of uppercase and lowercase and of which
    character is greater than or less than another character is locale
    dependent. This affects functions which support a case insensitive
    option or which compare or lowercase or uppercase their arguments.
    Case insensitive operations and comparisons will be accurate if
    both strings contain only ASCII characters. (If \c $LC_CTYPE is
    set, most Unix systems do "the right thing".) Functions that this
    affects include contains(), find(), findRev(), \l operator<(), \l
    operator<=(), \l operator>(), \l operator>=(), lower() and
    upper().

    This issue does not apply to \l{QString}s since they represent
    characters using Unicode.
    \endsidebar

    Performance note: The Q3CString methods for QRegExp searching are
    implemented by converting the Q3CString to a QString and performing
    the search on that. This implies a deep copy of the Q3CString data.
    If you are going to perform many QRegExp searches on a large
    Q3CString, you will get better performance by converting the
    Q3CString to a QString yourself, and then searching in the QString.
*/

/*!
    \fn Q3CString Q3CString::left(uint len)  const

//.........这里部分代码省略.........

void WindowMaterialGlazingInspectorView::onClearSelection()
{
  ModelObjectInspectorView::onClearSelection(); // call parent implementation
  detach();
}

int main(int argc, char *argv[])
{
    int nsockets = 0;
    struct event listeners[10];

    parseargs(argc, argv);

    if (g_foreground == 0) {
        detach();
        g_logfile = fopen(g_logfilename, "a");
        g_log_set_default_handler(logger, NULL);
    }

    g_handle_base[0] = 'H';
    g_handle_base[1] = ':';
    if (gethostname(g_handle_base+2, 128-28) != 0) {
        sprintf(g_handle_base+2, "hostname"); /* TODO: figure out some other unique identifier */
    }
    char *p = strchr(g_handle_base, '.');
    if (!p) p = g_handle_base + strlen(g_handle_base);
    *(p++) = ':';
    *p = 0;

    g_thread_init(NULL);

    event_init();
    //printf("%s %s\n", event_get_version(), event_get_method());

    signal(SIGPIPE, SIG_IGN);

    struct event sig_int, sig_hup, sig_term;/*, sig_pipe;*/
    if (g_foreground) {
        event_set(&sig_int, SIGINT, EV_SIGNAL|EV_PERSIST, signal_cb, &sig_int);
        event_add(&sig_int, NULL);
        event_set(&sig_hup, SIGHUP, EV_SIGNAL|EV_PERSIST, signal_cb, &sig_hup);
        event_add(&sig_hup, NULL);
    } else {
        signal(SIGINT, SIG_IGN);
        signal(SIGHUP, SIG_IGN);
    }
    event_set(&sig_term, SIGTERM, EV_SIGNAL|EV_PERSIST, signal_cb, &sig_term);
    event_add(&sig_term, NULL);
    /*event_set(&sig_pipe, SIGPIPE, EV_SIGNAL|EV_PERSIST, signal_cb, &sig_pipe);
    event_add(&sig_pipe, NULL);*/

    int s = listen_on(inet_addr(g_bind), g_port);
    if (s == -1) {
        perror("failed to listen on port ...");
        return -1;
    }
    event_set(&listeners[nsockets], s, EV_READ|EV_PERSIST,
              listener_cb, &listeners[nsockets]);
    event_add(&listeners[nsockets], NULL);
    nsockets++;

    g_message("listening on port %d", g_port);

    g_clients   = g_ptr_array_new();
    g_jobs = g_hash_table_new_full(g_str_hash, g_str_equal, NULL, (GDestroyNotify)job_free);
    g_jobqueue = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL, (GDestroyNotify)g_queue_free);
    g_uniq_jobs = g_hash_table_new_full(uniq_job_hash, uniq_job_equal, NULL, NULL);
    g_workers = g_hash_table_new_full(g_direct_hash, g_direct_equal, NULL, (GDestroyNotify)g_ptr_array_free);

    schedule_cleanup();

    g_message("gearmand running");
    event_dispatch();
    g_message("gearmand stopped");

    g_hash_table_destroy(g_workers);
    g_hash_table_destroy(g_uniq_jobs);
    g_hash_table_destroy(g_jobqueue);
    g_hash_table_destroy(g_jobs);
    g_ptr_array_free(g_clients, TRUE);

    freePools();

    if (g_foreground == 0)
        fclose(g_logfile);

    return 0;
}

/*!
    Inserts the field \a field at position \a pos in the record.

    \sa append() replace() remove()
 */
void QSqlRecord::insert(int pos, const QSqlField& field)
{
   detach();
   d->fields.insert(pos, field);
}

/*!
    \since 4.7

    Sets the outgoing option \a opt to value \a value.
    See \l{QAuthenticator#Options} for more information on outgoing options.

    \sa options(), option(), QAuthenticator#Options
*/
void QAuthenticator::setOption(const QString &opt, const QVariant &value)
{
    detach();
    d->options.insert(opt, value);
}

 void attach(string_type& string) {
     detach();
     this->string = boost::addressof(string);
 }

void MaterialAirWallInspectorView::onClearSelection()
{
  ModelObjectInspectorView::onClearSelection(); // call parent implementation
  detach();
}

QWSSharedMemory::~QWSSharedMemory()
{
    detach();
}

/*!
   Sets the text option structure that controls the layout process to the given \a textOption.

   \sa textOption()
*/
void QStaticText::setTextOption(const QTextOption &textOption)
{
    detach();
    data->textOption = textOption;
    data->invalidate();
}

/*!
    Sets the preferred width for this QStaticText. If the text is wider than the specified width,
    it will be broken into multiple lines and grow vertically. If the text cannot be split into
    multiple lines, it will be larger than the specified \a textWidth.

    Setting the preferred text width to a negative number will cause the text to be unbounded.

    Use size() to get the actual size of the text.

    \note This function will cause the layout of the text to require recalculation.

    \sa textWidth(), size()
*/
void QStaticText::setTextWidth(qreal textWidth)
{
    detach();
    data->textWidth = textWidth;
    data->invalidate();
}

/*!
   Sets the text format of the QStaticText to \a textFormat. If \a textFormat is set to
   Qt::AutoText (the default), the format of the text will try to be determined using the
   function Qt::mightBeRichText(). If the text format is Qt::PlainText, then the text will be
   displayed as is, whereas it will be interpreted as HTML if the format is Qt::RichText. HTML tags
   that alter the font of the text, its color, or its layout are supported by QStaticText.

   \note This function will cause the layout of the text to require recalculation.

   \sa textFormat(), setText(), text()
*/
void QStaticText::setTextFormat(Qt::TextFormat textFormat)
{
    detach();
    data->textFormat = textFormat;
    data->invalidate();
}

/*!
    Sets the text of the QStaticText to \a text.

    \note This function will cause the layout of the text to require recalculation.

    \sa text()
*/
void QStaticText::setText(const QString &text)
{
    detach();
    data->text = text;
    data->invalidate();
}

/// Closes the file and throws on error.
void fstream::close (void)
{
    if (m_fd >= 0 && ::close(m_fd))
	set_and_throw (badbit | failbit, "close");
    detach();
}

/*!
  Sets the \a user used for authentication.

  \sa QNetworkAccessManager::authenticationRequired()
*/
void QAuthenticator::setUser(const QString &user)
{
    detach();
    d->user = user;
    d->updateCredentials();
}

void Plot2DProfile::detachFromPlot(){
    detach();
}

 void TreeInspector::close(Event* ev)
 {
     detach();
     _getStage()->removeEventListeners(this);
     //return true;
 }

/*!
  Destroys this QScriptDebuggerBackend.
*/
QScriptDebuggerBackend::~QScriptDebuggerBackend()
{
    detach();
}

//-------------------------------------------------------------------------------------
bool DBInterfaceMysql::attach(const char* databaseName)
{
	if(!_g_installedWatcher)
	{
		initializeWatcher();
	}

	if(db_port_ == 0)
		db_port_ = 3306;
	
	if(databaseName != NULL)
		kbe_snprintf(db_name_, MAX_BUF, "%s", databaseName);

	hasLostConnection_ = false;

	try
	{
		pMysql_ = mysql_init(0);
		if(pMysql_ == NULL)
		{
			ERROR_MSG("DBInterfaceMysql::attach: mysql_init is error!\n");
			return false;
		}
		
		DEBUG_MSG(fmt::format("DBInterfaceMysql::attach: connect: {}:{} starting...\n", db_ip_, db_port_));

		int ntry = 0;

__RECONNECT:
		if(mysql_real_connect(mysql(), db_ip_, db_username_, 
    		db_password_, db_name_, db_port_, NULL, 0)) // CLIENT_MULTI_STATEMENTS  
		{
			if(mysql_select_db(mysql(), db_name_) != 0)
			{
				ERROR_MSG(fmt::format("DBInterfaceMysql::attach: Could not set active db[{}]\n",
					db_name_));

				detach();
				return false;
			}
		}
		else
		{
			if (mysql_errno(pMysql_) == 1049 && ntry++ == 0)
			{
				if (mysql())
				{
					::mysql_close(mysql());
					pMysql_ = NULL;
				}

				pMysql_ = mysql_init(0);
				if (pMysql_ == NULL)
				{
					ERROR_MSG("DBInterfaceMysql::attach: mysql_init is error!\n");
					return false;
				}

				if (mysql_real_connect(mysql(), db_ip_, db_username_,
					db_password_, NULL, db_port_, NULL, 0)) // CLIENT_MULTI_STATEMENTS  
				{
					this->createDatabaseIfNotExist();
					if (mysql_select_db(mysql(), db_name_) != 0)
					{
						goto __RECONNECT;
					}
				}
				else
				{
					goto __RECONNECT;
				}
			}
			else
			{
				ERROR_MSG(fmt::format("DBInterfaceMysql::attach: mysql_errno={}, mysql_error={}\n",
					mysql_errno(pMysql_), mysql_error(pMysql_)));

				detach();
				return false;
			}
		}

		if (mysql_set_character_set(mysql(), "utf8") != 0)
		{
			ERROR_MSG("DBInterfaceMysql::attach: Could not set client connection character set to UTF-8\n" );
			return false;
		}

		// 不需要关闭自动提交，底层会START TRANSACTION之后再COMMIT
		// mysql_autocommit(mysql(), 0);

		char characterset_sql[MAX_BUF];
		kbe_snprintf(characterset_sql, MAX_BUF, "ALTER DATABASE CHARACTER SET %s COLLATE %s", 
			characterSet_.c_str(), collation_.c_str());

		query(&characterset_sql[0], strlen(characterset_sql), false);
	}
	catch (std::exception& e)
	{
//.........这里部分代码省略.........

void QSqlRecord::append(const QSqlField& field)
{
    detach();
    d->fields.append(field);
}