tclunixchan.c

tcl是工具命令语言

    fsPtr->validMask = mode | TCL_EXCEPTION;
    fsPtr->channel = Tcl_CreateChannel(channelTypePtr, channelName,
	    (ClientData) fsPtr, mode);

    return fsPtr->channel;
}

/*
 *----------------------------------------------------------------------
 *
 * TcpBlockModeProc --
 *
 *	This procedure is invoked by the generic IO level to set blocking
 *	and nonblocking mode on a TCP socket based channel.
 *
 * Results:
 *	0 if successful, errno when failed.
 *
 * Side effects:
 *	Sets the device into blocking or nonblocking mode.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
static int
TcpBlockModeProc(instanceData, mode)
    ClientData instanceData;		/* Socket state. */
    int mode;				/* The mode to set. Can be one of
					 * TCL_MODE_BLOCKING or
					 * TCL_MODE_NONBLOCKING. */
{
    TcpState *statePtr = (TcpState *) instanceData;
    int setting;

#ifndef USE_FIONBIO
    setting = fcntl(statePtr->fd, F_GETFL);
    if (mode == TCL_MODE_BLOCKING) {
	statePtr->flags &= (~(TCP_ASYNC_SOCKET));
	setting &= (~(O_NONBLOCK));
    } else {
	statePtr->flags |= TCP_ASYNC_SOCKET;
	setting |= O_NONBLOCK;
    }
    if (fcntl(statePtr->fd, F_SETFL, setting) < 0) {
	return errno;
    }
#else /* USE_FIONBIO */
    if (mode == TCL_MODE_BLOCKING) {
	statePtr->flags &= (~(TCP_ASYNC_SOCKET));
	setting = 0;
	if (ioctl(statePtr->fd, (int) FIONBIO, &setting) == -1) {
	    return errno;
	}
    } else {
	statePtr->flags |= TCP_ASYNC_SOCKET;
	setting = 1;
	if (ioctl(statePtr->fd, (int) FIONBIO, &setting) == -1) {
	    return errno;
	}
    }
#endif /* !USE_FIONBIO */

    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * WaitForConnect --
 *
 *	Waits for a connection on an asynchronously opened socket to
 *	be completed.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The socket is connected after this function returns.
 *
 *----------------------------------------------------------------------
 */

static int
WaitForConnect(statePtr, errorCodePtr)
    TcpState *statePtr;		/* State of the socket. */
    int *errorCodePtr;		/* Where to store errors? */
{
    int timeOut;		/* How long to wait. */
    int state;			/* Of calling TclWaitForFile. */
    int flags;			/* fcntl flags for the socket. */

    /*
     * If an asynchronous connect is in progress, attempt to wait for it
     * to complete before reading.
     */

    if (statePtr->flags & TCP_ASYNC_CONNECT) {
	if (statePtr->flags & TCP_ASYNC_SOCKET) {
	    timeOut = 0;
	} else {
	    timeOut = -1;
	}
	errno = 0;
	state = TclUnixWaitForFile(statePtr->fd,
		TCL_WRITABLE | TCL_EXCEPTION, timeOut);
	if (!(statePtr->flags & TCP_ASYNC_SOCKET)) {
#ifndef USE_FIONBIO
	    flags = fcntl(statePtr->fd, F_GETFL);
	    flags &= (~(O_NONBLOCK));
	    (void) fcntl(statePtr->fd, F_SETFL, flags);
#else /* USE_FIONBIO */
	    flags = 0;
	    (void) ioctl(statePtr->fd, FIONBIO, &flags);
#endif /* !USE_FIONBIO */
	}
	if (state & TCL_EXCEPTION) {
	    return -1;
	}
	if (state & TCL_WRITABLE) {
	    statePtr->flags &= (~(TCP_ASYNC_CONNECT));
	} else if (timeOut == 0) {
	    *errorCodePtr = errno = EWOULDBLOCK;
	    return -1;
	}
    }
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * TcpInputProc --
 *
 *	This procedure is invoked by the generic IO level to read input
 *	from a TCP socket based channel.
 *
 *	NOTE: We cannot share code with FilePipeInputProc because here
 *	we must use recv to obtain the input from the channel, not read.
 *
 * Results:
 *	The number of bytes read is returned or -1 on error. An output
 *	argument contains the POSIX error code on error, or zero if no
 *	error occurred.
 *
 * Side effects:
 *	Reads input from the input device of the channel.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
static int
TcpInputProc(instanceData, buf, bufSize, errorCodePtr)
    ClientData instanceData;		/* Socket state. */
    char *buf;				/* Where to store data read. */
    int bufSize;			/* How much space is available
					 * in the buffer? */
    int *errorCodePtr;			/* Where to store error code. */
{
    TcpState *statePtr = (TcpState *) instanceData;
    int bytesRead, state;

    *errorCodePtr = 0;
    state = WaitForConnect(statePtr, errorCodePtr);
    if (state != 0) {
	return -1;
    }
    bytesRead = recv(statePtr->fd, buf, (size_t) bufSize, 0);
    if (bytesRead > -1) {
	return bytesRead;
    }
    if (errno == ECONNRESET) {
	/*
	 * Turn ECONNRESET into a soft EOF condition.
	 */

	return 0;
    }
    *errorCodePtr = errno;
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * TcpOutputProc --
 *
 *	This procedure is invoked by the generic IO level to write output
 *	to a TCP socket based channel.
 *
 *	NOTE: We cannot share code with FilePipeOutputProc because here
 *	we must use send, not write, to get reliable error reporting.
 *
 * Results:
 *	The number of bytes written is returned. An output argument is
 *	set to a POSIX error code if an error occurred, or zero.
 *
 * Side effects:
 *	Writes output on the output device of the channel.
 *
 *----------------------------------------------------------------------
 */

static int
TcpOutputProc(instanceData, buf, toWrite, errorCodePtr)
    ClientData instanceData;		/* Socket state. */
    CONST char *buf;			/* The data buffer. */
    int toWrite;			/* How many bytes to write? */
    int *errorCodePtr;			/* Where to store error code. */
{
    TcpState *statePtr = (TcpState *) instanceData;
    int written;
    int state;				/* Of waiting for connection. */

    *errorCodePtr = 0;
    state = WaitForConnect(statePtr, errorCodePtr);
    if (state != 0) {
	return -1;
    }
    written = send(statePtr->fd, buf, (size_t) toWrite, 0);
    if (written > -1) {
	return written;
    }
    *errorCodePtr = errno;
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * TcpCloseProc --
 *
 *	This procedure is invoked by the generic IO level to perform
 *	channel-type-specific cleanup when a TCP socket based channel
 *	is closed.
 *
 * Results:
 *	0 if successful, the value of errno if failed.
 *
 * Side effects:
 *	Closes the socket of the channel.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
static int
TcpCloseProc(instanceData, interp)
    ClientData instanceData;	/* The socket to close. */
    Tcl_Interp *interp;		/* For error reporting - unused. */
{
    TcpState *statePtr = (TcpState *) instanceData;
    int errorCode = 0;

    /*
     * Delete a file handler that may be active for this socket if this
     * is a server socket - the file handler was created automatically
     * by Tcl as part of the mechanism to accept new client connections.
     * Channel handlers are already deleted in the generic IO channel
     * closing code that called this function, so we do not have to
     * delete them here.
     */

    Tcl_DeleteFileHandler(statePtr->fd);

    if (close(statePtr->fd) < 0) {
	errorCode = errno;
    }
    ckfree((char *) statePtr);

    return errorCode;
}

/*
 *----------------------------------------------------------------------
 *
 * TcpGetOptionProc --
 *
 *	Computes an option value for a TCP socket based channel, or a
 *	list of all options and their values.
 *
 *	Note: This code is based on code contributed by John Haxby.
 *
 * Results:
 *	A standard Tcl result. The value of the specified option or a
 *	list of all options and their values is returned in the
 *	supplied DString. Sets Error message if needed.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
TcpGetOptionProc(instanceData, interp, optionName, dsPtr)
    ClientData instanceData;	 /* Socket state. */
    Tcl_Interp *interp;		 /* For error reporting - can be NULL. */
    CONST char *optionName;	 /* Name of the option to
				  * retrieve the value for, or
				  * NULL to get all options and
				  * their values. */
    Tcl_DString *dsPtr;		 /* Where to store the computed
				  * value; initialized by caller. */
{
    TcpState *statePtr = (TcpState *) instanceData;
    struct sockaddr_in sockname;
    struct sockaddr_in peername;
    struct hostent *hostEntPtr;
    socklen_t size = sizeof(struct sockaddr_in);
    size_t len = 0;
    char buf[TCL_INTEGER_SPACE];

    if (optionName != (char *) NULL) {
	len = strlen(optionName);
    }

    if ((len > 1) && (optionName[1] == 'e') &&
	    (strncmp(optionName, "-error", len) == 0)) {
	socklen_t optlen = sizeof(int);
	int err, ret;

	ret = getsockopt(statePtr->fd, SOL_SOCKET, SO_ERROR,
		(char *)&err, &optlen);
	if (ret < 0) {
	    err = errno;
	}
	if (err != 0) {
	    Tcl_DStringAppend(dsPtr, Tcl_ErrnoMsg(err), -1);
	}
	return TCL_OK;
    }

    if ((len == 0) ||
	    ((len > 1) && (optionName[1] == 'p') &&
		    (strncmp(optionName, "-peername", len) == 0))) {
	if (getpeername(statePtr->fd, (struct sockaddr *) &peername,
		&size) >= 0) {
	    if (len == 0) {
		Tcl_DStringAppendElement(dsPtr, "-peername");
		Tcl_DStringStartSublist(dsPtr);
	    }
	    Tcl_DStringAppendElement(dsPtr, inet_ntoa(peername.sin_addr));
	    hostEntPtr = gethostbyaddr(			/* INTL: Native. */
		    (char *) &peername.sin_addr,
		    sizeof(peername.sin_addr), AF_INET);
	    if (hostEntPtr != NULL) {
		Tcl_DString ds;

		Tcl_ExternalToUtfDString(NULL, hostEntPtr->h_name, -1, &ds);
		Tcl_DStringAppendElement(dsPtr, Tcl_DStringValue(&ds));
	    } else {
		Tcl_DStringAppendElement(dsPtr, inet_ntoa(peername.sin_addr));
	    }
	    TclFormatInt(buf, ntohs(peername.sin_port));
	    Tcl_DStringAppendElement(dsPtr, buf);
	    if (len == 0) {
		Tcl_DStringEndSublist(dsPtr);
	    } else {
		return TCL_OK;
	    }
	} else {
	    /*
	     * getpeername failed - but if we were asked for all the options
	     * (len==0), don't flag an error at that point because it could
	     * be an fconfigure request on a server socket. (which have
	     * no peer). same must be done on win&mac.
	     */

	    if (len) {
		if (interp) {
		    Tcl_AppendResult(interp, "can't get peername: ",
			    Tcl_PosixError(interp), (char *) NULL);
		}
		return TCL_ERROR;
	    }
	}
    }

    if ((len == 0) ||
	    ((len > 1) && (optionName[1] == 's') &&
	    (strncmp(optionName, "-sockname", len) == 0))) {
	if (getsockname(statePtr->fd, (struct sockaddr *) &sockname,
		&size) >= 0) {
	    if (len == 0) {
		Tcl_DStringAppendElement(dsPtr, "-sockname");
		Tcl_DStringStartSublist(dsPtr);
	    }
	    Tcl_DStringAppendElement(dsPtr, inet_ntoa(sockname.sin_addr));
	    hostEntPtr = gethostbyaddr(			/* INTL: Native. */
		    (char *) &sockname.sin_addr,
		    sizeof(sockname.sin_addr), AF_INET);
	    if (hostEntPtr != (struct hostent *) NULL) {
		Tcl_DString ds;

		Tcl_ExternalToUtfDString(NULL, hostEntPtr->h_name, -1, &ds);
		Tcl_DStringAppendElement(dsPtr, Tcl_DStringValue(&ds));
	    } else {
		Tcl_DStringAppendElement(dsPtr, inet_ntoa(sockname.sin_addr));
	    }
	    TclFormatInt(buf, ntohs(sockname.sin_port));
	    Tcl_DStringAppendElement(dsPtr, buf);
	    if (len == 0) {
		Tcl_DStringEndSublist(dsPtr);
	    } else {
		return TCL_OK;
	    }
	} else {
	    if (interp) {
		Tcl_AppendResult(interp, "can't get sockname: ",
			Tcl_PosixError(interp), (char *) NULL);
	    }
	    return TCL_ERROR;
	}
    }

    if (len > 0) {
	return Tcl_BadChannelOption(interp, optionName, "peername sockname");
    }

    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * TcpWatchProc --
 *
 *	Initialize the notifier to watch the fd from this channel.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Sets up the notifier so that a future event on the channel will
 *	be seen by Tcl.
 *
 *----------------------------------------------------------------------
 */

static void
TcpWatchProc(instanceData, mask)
    ClientData instanceData;		/* The socket state. */
    int mask;				/* Events of interest; an OR-ed
					 * combination of TCL_READABLE,
					 * TCL_WRITABLE and TCL_EXCEPTION. */
{
    TcpState *statePtr = (TcpState *) instanceData;

    /*
     * Make sure we don't mess with server sockets since they will never
     * be readable or writable at the Tcl level.  This keeps Tcl scripts
     * from interfering with the -accept behavior.
     */

    if (!statePtr->acceptProc) {
	if (mask) {
	    Tcl_CreateFileHandler(statePtr->fd, mask,
		    (Tcl_FileProc *) Tcl_NotifyChannel,
		    (ClientData) statePtr->channel);
	} else {
	    Tcl_DeleteFileHandler(statePtr->fd);
	}
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TcpGetHandleProc --
 *
 *	Called from Tcl_GetChannelHandle to retrieve OS handles from inside
 *	a TCP socket based channel.
 *
 * Results:
 *	Returns TCL_OK with the fd in handlePtr, or TCL_ERROR if
 *	there is no handle for the specified direction. 
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------