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Eneboo - Documentación para desarrolladores
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Eneboo - Documentación para desarrolladores
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The QSocket class provides a buffered TCP connection.network. Más...
#include <qsocket.h>
Tipos públicos | |
| enum | Error { ErrConnectionRefused, ErrHostNotFound, ErrSocketRead, ErrConnectionRefused, ErrHostNotFound, ErrSocketRead } |
| enum | State { Idle, HostLookup, Connecting, Connected, Closing, Connection = Connected, Idle, HostLookup, Connecting, Connected, Closing, Connection = Connected } |
| enum | Error { ErrConnectionRefused, ErrHostNotFound, ErrSocketRead, ErrConnectionRefused, ErrHostNotFound, ErrSocketRead } |
| enum | State { Idle, HostLookup, Connecting, Connected, Closing, Connection = Connected, Idle, HostLookup, Connecting, Connected, Closing, Connection = Connected } |
Señales | |
| void | hostFound () |
| void | connected () |
| void | connectionClosed () |
| void | delayedCloseFinished () |
| void | readyRead () |
| void | bytesWritten (int nbytes) |
| void | error (int) |
| void | hostFound () |
| void | connected () |
| void | connectionClosed () |
| void | delayedCloseFinished () |
| void | readyRead () |
| void | bytesWritten (int nbytes) |
| void | error (int) |
Métodos públicos | |
| QSocket (QObject *parent=0, const char *name=0) | |
| virtual | ~QSocket () |
| State | state () const |
| int | socket () const |
| virtual void | setSocket (int) |
| QSocketDevice * | socketDevice () |
| virtual void | setSocketDevice (QSocketDevice *) |
| virtual void | connectToHost (const QString &host, Q_UINT16 port) |
| QString | peerName () const |
| bool | open (int mode) |
| void | close () |
| void | flush () |
| Offset | size () const |
| Offset | at () const |
| bool | at (Offset) |
| bool | atEnd () const |
| Q_ULONG | bytesAvailable () const |
| Q_ULONG | waitForMore (int msecs, bool *timeout) const |
| Q_ULONG | waitForMore (int msecs) const |
| Q_ULONG | bytesToWrite () const |
| void | clearPendingData () |
| Q_LONG | readBlock (char *data, Q_ULONG maxlen) |
| Q_LONG | writeBlock (const char *data, Q_ULONG len) |
| Q_LONG | readLine (char *data, Q_ULONG maxlen) |
| int | getch () |
| int | putch (int) |
| int | ungetch (int) |
| bool | canReadLine () const |
| virtual QString | readLine () |
| Q_UINT16 | port () const |
| Q_UINT16 | peerPort () const |
| QHostAddress | address () const |
| QHostAddress | peerAddress () const |
| void | setReadBufferSize (Q_ULONG) |
| Q_ULONG | readBufferSize () const |
| QSocket (QObject *parent=0, const char *name=0) | |
| virtual | ~QSocket () |
| State | state () const |
| int | socket () const |
| virtual void | setSocket (int) |
| QSocketDevice * | socketDevice () |
| virtual void | setSocketDevice (QSocketDevice *) |
| virtual void | connectToHost (const QString &host, Q_UINT16 port) |
| QString | peerName () const |
| bool | open (int mode) |
| void | close () |
| void | flush () |
| Offset | size () const |
| Offset | at () const |
| bool | at (Offset) |
| bool | atEnd () const |
| Q_ULONG | bytesAvailable () const |
| Q_ULONG | waitForMore (int msecs, bool *timeout) const |
| Q_ULONG | waitForMore (int msecs) const |
| Q_ULONG | bytesToWrite () const |
| void | clearPendingData () |
| Q_LONG | readBlock (char *data, Q_ULONG maxlen) |
| Q_LONG | writeBlock (const char *data, Q_ULONG len) |
| Q_LONG | readLine (char *data, Q_ULONG maxlen) |
| int | getch () |
| int | putch (int) |
| int | ungetch (int) |
| bool | canReadLine () const |
| virtual QString | readLine () |
| Q_UINT16 | port () const |
| Q_UINT16 | peerPort () const |
| QHostAddress | address () const |
| QHostAddress | peerAddress () const |
| void | setReadBufferSize (Q_ULONG) |
| Q_ULONG | readBufferSize () const |
Slots protegidos | |
| virtual void | sn_read (bool force=FALSE) |
| virtual void | sn_write () |
| virtual void | sn_read (bool force=FALSE) |
| virtual void | sn_write () |
The QSocket class provides a buffered TCP connection.
network.
It provides a totally non-blocking QIODevice, and modifies and extends the API of QIODevice with socket-specific code.
Note that a QApplication must have been constructed before this class can be used.
The functions you're likely to call most are connectToHost(), bytesAvailable(), canReadLine() and the ones it inherits from QIODevice.
connectToHost() is the most-used function. As its name implies, it opens a connection to a named host.
Most network protocols are either packet-oriented or line-oriented. canReadLine() indicates whether a connection contains an entire unread line or not, and bytesAvailable() returns the number of bytes available for reading.
The signals error(), connected(), readyRead() and connectionClosed() inform you of the progress of the connection. There are also some less commonly used signals. hostFound() is emitted when connectToHost() has finished its DNS lookup and is starting its TCP connection. delayedCloseFinished() is emitted when close() succeeds. bytesWritten() is emitted when QSocket moves data from its "to be written" queue into the TCP implementation.
There are several access functions for the socket: state() returns whether the object is idle, is doing a DNS lookup, is connecting, has an operational connection, etc. address() and port() return the IP address and port used for the connection. The peerAddress() and peerPort() functions return the IP address and port used by the peer, and peerName() returns the name of the peer (normally the name that was passed to connectToHost()). socketDevice() returns a pointer to the QSocketDevice used for this socket.
QSocket inherits QIODevice, and reimplements some functions. In general, you can treat it as a QIODevice for writing, and mostly also for reading. The match isn't perfect, since the QIODevice API is designed for devices that are controlled by the same machine, and an asynchronous peer-to-peer network connection isn't quite like that. For example, there is nothing that matches QIODevice::size() exactly. The documentation for open(), close(), flush(), size(), at(), atEnd(), readBlock(), writeBlock(), getch(), putch(), ungetch() and readLine() describes the differences in detail.
| enum QSocket::Error |
This enum specifies the possible errors: ErrConnectionRefused if the connection was refused ErrHostNotFound if the host was not found ErrSocketRead if a read from the socket failed
| enum QSocket::Error |
| enum QSocket::State |
| enum QSocket::State |
This enum defines the connection states:
Idle if there is no connection HostLookup during a DNS lookup Connecting during TCP connection establishment Connected when there is an operational connection Closing if the socket is closing down, but is not yet closed.
| QSocket::QSocket | ( | QObject * | parent = 0, |
| const char * | name = 0 |
||
| ) |
Creates a QSocket object in QSocket::Idle state.
The parent and name arguments are passed on to the QObject constructor.
Note that a QApplication must have been constructed before sockets can be used.
| QSocket::~QSocket | ( | ) | [virtual] |
Destroys the socket. Closes the connection if necessary.
| QSocket::QSocket | ( | QObject * | parent = 0, |
| const char * | name = 0 |
||
| ) |
| virtual QSocket::~QSocket | ( | ) | [virtual] |
| QHostAddress QSocket::address | ( | ) | const |
Returns the host address of this socket. (This is normally the main IP address of the host, but can be e.g. 127.0.0.1 for connections to localhost.)
| QHostAddress QSocket::address | ( | ) | const |
| QIODevice::Offset QSocket::at | ( | ) | const [virtual] |
| Offset QSocket::at | ( | ) | const [virtual] |
Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta. Moves the read index forward to index and returns TRUE if the operation was successful; otherwise returns FALSE. Moving the index forward means skipping incoming data.
Reimplementado de QIODevice.
| bool QSocket::atEnd | ( | ) | const [virtual] |
Virtual function that returns TRUE if the I/O device position is at the end of the input; otherwise returns FALSE.
Reimplementado de QIODevice.
| bool QSocket::atEnd | ( | ) | const [virtual] |
Returns TRUE if there is no more data to read; otherwise returns FALSE.
Reimplementado de QIODevice.
| Q_ULONG QSocket::bytesAvailable | ( | ) | const |
| Q_ULONG QSocket::bytesAvailable | ( | ) | const |
Returns the number of incoming bytes that can be read, i.e. the size of the input buffer. Equivalent to size().
This function can trigger the readyRead() signal, if more data has arrived on the socket.
| Q_ULONG QSocket::bytesToWrite | ( | ) | const |
Returns the number of bytes that are waiting to be written, i.e. the size of the output buffer.
| Q_ULONG QSocket::bytesToWrite | ( | ) | const |
| void QSocket::bytesWritten | ( | int | nbytes | ) | [signal] |
This signal is emitted when data has been written to the network. The nbytes parameter specifies how many bytes were written.
The bytesToWrite() function is often used in the same context; it indicates how many buffered bytes there are left to write.
| void QSocket::bytesWritten | ( | int | nbytes | ) | [signal] |
| bool QSocket::canReadLine | ( | ) | const |
| bool QSocket::canReadLine | ( | ) | const |
Returns TRUE if it's possible to read an entire line of text from this socket at this time; otherwise returns FALSE.
Note that if the peer closes the connection unexpectedly, this function returns FALSE. This means that loops such as this won't work:
while( !socket->canReadLine() ) // WRONG ;
| void QSocket::clearPendingData | ( | ) |
Deletes the data that is waiting to be written. This is useful if you want to close the socket without waiting for all the data to be written.
| void QSocket::clearPendingData | ( | ) |
| void QSocket::close | ( | void | ) | [virtual] |
| void QSocket::close | ( | void | ) | [virtual] |
Closes the socket.
The read buffer is cleared.
If the output buffer is empty, the state is set to QSocket::Idle and the connection is terminated immediately. If the output buffer still contains data to be written, QSocket goes into the QSocket::Closing state and the rest of the data will be written. When all of the outgoing data have been written, the state is set to QSocket::Idle and the connection is terminated. At this point, the delayedCloseFinished() signal is emitted.
If you don't want that the data of the output buffer is written, call clearPendingData() before you call close().
Implementa QIODevice.
| void QSocket::connected | ( | ) | [signal] |
This signal is emitted after connectToHost() has been called and a connection has been successfully established.
| void QSocket::connected | ( | ) | [signal] |
| void QSocket::connectionClosed | ( | ) | [signal] |
This signal is emitted when the other end has closed the connection. The read buffers may contain buffered input data which you can read after the connection was closed.
| void QSocket::connectionClosed | ( | ) | [signal] |
| void QSocket::connectToHost | ( | const QString & | host, |
| Q_UINT16 | port | ||
| ) | [virtual] |
Attempts to make a connection to host on the specified port and return immediately.
Any connection or pending connection is closed immediately, and QSocket goes into the HostLookup state. When the lookup succeeds, it emits hostFound(), starts a TCP connection and goes into the Connecting state. Finally, when the connection succeeds, it emits connected() and goes into the Connected state. If there is an error at any point, it emits error().
host may be an IP address in string form, or it may be a DNS name. QSocket will do a normal DNS lookup if required. Note that port is in native byte order, unlike some other libraries.
| virtual void QSocket::connectToHost | ( | const QString & | host, |
| Q_UINT16 | port | ||
| ) | [virtual] |
| void QSocket::delayedCloseFinished | ( | ) | [signal] |
This signal is emitted when a delayed close is finished.
If you call close() and there is buffered output data to be written, QSocket goes into the QSocket::Closing state and returns immediately. It will then keep writing to the socket until all the data has been written. Then, the delayedCloseFinished() signal is emitted.
| void QSocket::delayedCloseFinished | ( | ) | [signal] |
| void QSocket::error | ( | int | t0 | ) | [signal] |
This signal is emitted after an error occurred. The parameter is the Error value.
| void QSocket::error | ( | int | ) | [signal] |
| void QSocket::flush | ( | ) | [virtual] |
Implementation of the abstract virtual QIODevice::flush() function.
Implementa QIODevice.
| void QSocket::flush | ( | ) | [virtual] |
Flushes an open I/O device.
This virtual function must be reimplemented by all subclasses.
Implementa QIODevice.
| int QSocket::getch | ( | ) | [virtual] |
| int QSocket::getch | ( | ) | [virtual] |
Reads a single byte/character from the internal read buffer. Returns the byte/character read, or -1 if there is nothing to be read.
Implementa QIODevice.
| void QSocket::hostFound | ( | ) | [signal] |
This signal is emitted after connectToHost() has been called and the host lookup has succeeded.
| void QSocket::hostFound | ( | ) | [signal] |
Opens the I/O device using the specified mode. Returns TRUE if the device was successfully opened; otherwise returns FALSE.
The mode parameter mode must be an OR'ed combination of the following flags. Mode flags Meaning IO_Raw specifies raw (unbuffered) file access. IO_ReadOnly opens a file in read-only mode. IO_WriteOnly opens a file in write-only mode. IO_ReadWrite opens a file in read/write mode. IO_Append sets the file index to the end of the file. IO_Truncate truncates the file. IO_Translate enables carriage returns and linefeed translation for text files under MS-DOS, Windows and Macintosh. On Unix systems this flag has no effect. Use with caution as it will also transform every linefeed written to the file into a CRLF pair. This is likely to corrupt your file if you write write binary data. Cannot be combined with IO_Raw.
This virtual function must be reimplemented by all subclasses.
Implementa QIODevice.
| QHostAddress QSocket::peerAddress | ( | ) | const |
| QHostAddress QSocket::peerAddress | ( | ) | const |
Returns the address of the connected peer if the socket is in Connected state; otherwise an empty QHostAddress is returned.
| QString QSocket::peerName | ( | ) | const |
| QString QSocket::peerName | ( | ) | const |
Returns the host name as specified to the connectToHost() function. An empty string is returned if none has been set.
| Q_UINT16 QSocket::peerPort | ( | ) | const |
| Q_UINT16 QSocket::peerPort | ( | ) | const |
Returns the peer's host port number, normally as specified to the connectToHost() function. If none has been set, this function returns 0.
Note that Qt always uses native byte order, i.e. 67 is 67 in Qt; there is no need to call htons().
| Q_UINT16 QSocket::port | ( | ) | const |
| Q_UINT16 QSocket::port | ( | ) | const |
Returns the host port number of this socket, in native byte order.
| Q_LONG QSocket::readBlock | ( | char * | data, |
| Q_ULONG | maxlen | ||
| ) | [virtual] |
Reads at most maxlen bytes from the I/O device into data and returns the number of bytes actually read.
This function should return -1 if a fatal error occurs and should return 0 if there are no bytes to read.
The device must be opened for reading, and data must not be 0.
This virtual function must be reimplemented by all subclasses.
Implementa QIODevice.
| Q_LONG QSocket::readBlock | ( | char * | data, |
| Q_ULONG | maxlen | ||
| ) | [virtual] |
Reads maxlen bytes from the socket into data and returns the number of bytes read. Returns -1 if an error occurred.
Implementa QIODevice.
| Q_ULONG QSocket::readBufferSize | ( | ) | const |
| Q_ULONG QSocket::readBufferSize | ( | ) | const |
Returns the size of the read buffer.
| Q_LONG QSocket::readLine | ( | char * | data, |
| Q_ULONG | maxlen | ||
| ) | [virtual] |
Reads a line of text, (or up to maxlen bytes if a newline isn't encountered) plus a terminating '\0' into data. If there is a newline at the end if the line, it is not stripped.
Returns the number of bytes read including the terminating '\0', or -1 if an error occurred.
This virtual function can be reimplemented much more efficiently by the most subclasses.
Reimplementado de QIODevice.
| virtual QString QSocket::readLine | ( | ) | [virtual] |
| Q_LONG QSocket::readLine | ( | char * | data, |
| Q_ULONG | maxlen | ||
| ) | [virtual] |
Reimplementado de QIODevice.
| QString QSocket::readLine | ( | ) | [virtual] |
Returns a line of text including a terminating newline character (
). Returns "" if canReadLine() returns FALSE.
| void QSocket::readyRead | ( | ) | [signal] |
This signal is emitted every time there is new incoming data.
Bear in mind that new incoming data is only reported once; if you do not read all the data, this class buffers the data and you can read it later, but no signal is emitted unless new data arrives. A good practice is to read all data in the slot connected to this signal unless you are sure that you need to receive more data to be able to process it.
| void QSocket::readyRead | ( | ) | [signal] |
| void QSocket::setReadBufferSize | ( | Q_ULONG | bufSize | ) |
Sets the size of the QSocket's internal read buffer to bufSize.
Usually QSocket reads all data that is available from the operating system's socket. If the buffer size is limited to a certain size, this means that the QSocket class doesn't buffer more than this size of data.
If the size of the read buffer is 0, the read buffer is unlimited and all incoming data is buffered. This is the default.
If you read the data in the readyRead() signal, you shouldn't use this option since it might slow down your program unnecessary. This option is useful if you only need to read the data at certain points in time, like in a realtime streaming application.
| void QSocket::setReadBufferSize | ( | Q_ULONG | ) |
| virtual void QSocket::setSocket | ( | int | ) | [virtual] |
| void QSocket::setSocket | ( | int | socket | ) | [virtual] |
| virtual void QSocket::setSocketDevice | ( | QSocketDevice * | ) | [virtual] |
| void QSocket::setSocketDevice | ( | QSocketDevice * | device | ) | [virtual] |
Sets the internal socket device to device. Passing a device of 0 will cause the internal socket device to be used. Any existing connection will be disconnected before using the new device.
The new device should not be connected before being associated with a QSocket; after setting the socket call connectToHost() to make the connection.
This function is useful if you need to subclass QSocketDevice and want to use the QSocket API, for example, to implement Unix domain sockets.
| QIODevice::Offset QSocket::size | ( | ) | const [virtual] |
Returns the number of incoming bytes that can be read right now (like bytesAvailable()).
Implementa QIODevice.
| Offset QSocket::size | ( | ) | const [virtual] |
| virtual void QSocket::sn_read | ( | bool | force = FALSE | ) | [protected, virtual, slot] |
| void QSocket::sn_read | ( | bool | force = FALSE | ) | [protected, virtual, slot] |
| void QSocket::sn_write | ( | ) | [protected, virtual, slot] |
| virtual void QSocket::sn_write | ( | ) | [protected, virtual, slot] |
| int QSocket::socket | ( | ) | const |
| int QSocket::socket | ( | ) | const |
Returns the socket number, or -1 if there is no socket at the moment.
| QSocketDevice * QSocket::socketDevice | ( | ) |
Returns a pointer to the internal socket device.
There is normally no need to manipulate the socket device directly since this class does the necessary setup for most applications.
| QSocketDevice* QSocket::socketDevice | ( | ) |
| State QSocket::state | ( | ) | const |
Returns bits OR'ed together that specify the current state.
The flags are: IO_Open.
Subclasses may define additional flags.
Reimplementado de QIODevice.
| QSocket::State QSocket::state | ( | ) | const |
Returns the current state of the socket connection.
Reimplementado de QIODevice.
This implementation of the virtual function QIODevice::ungetch() prepends the character ch to the read buffer so that the next read returns this character as the first character of the output.
Implementa QIODevice.
| Q_ULONG QSocket::waitForMore | ( | int | msecs | ) | const |
Esta es una función miembro sobrecargada que se suministra por conveniencia. Difiere de la anterior función solamente en los argumentos que acepta.
| Q_ULONG QSocket::waitForMore | ( | int | msecs | ) | const |
Wait up to msecs milliseconds for more data to be available.
If msecs is -1 the call will block indefinitely.
Returns the number of bytes available.
If timeout is non-null and no error occurred (i.e. it does not return -1): this function sets *timeout to TRUE, if the reason for returning was that the timeout was reached; otherwise it sets *timeout to FALSE. This is useful to find out if the peer closed the connection.
| Q_LONG QSocket::writeBlock | ( | const char * | data, |
| Q_ULONG | len | ||
| ) | [virtual] |
Writes len bytes from data to the I/O device and returns the number of bytes actually written.
This function should return -1 if a fatal error occurs.
This virtual function must be reimplemented by all subclasses.
Implementa QIODevice.
| Q_LONG QSocket::writeBlock | ( | const char * | data, |
| Q_ULONG | len | ||
| ) | [virtual] |
Writes len bytes to the socket from data and returns the number of bytes written. Returns -1 if an error occurred.
Implementa QIODevice.
1.7.4
