tclwinchan.c

这是leon3处理器的交叉编译链

/* 
 * tclWinChan.c
 *
 *	Channel drivers for Windows channels based on files, command
 *	pipes and TCP sockets.
 *
 * Copyright (c) 1995-1997 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclWinChan.c,v 1.24 2002/07/08 10:08:58 vincentdarley Exp $
 */

#include "tclWinInt.h"

/*
 * State flags used in the info structures below.
 */

#define FILE_PENDING	(1<<0)	/* Message is pending in the queue. */
#define FILE_ASYNC	(1<<1)	/* Channel is non-blocking. */
#define FILE_APPEND	(1<<2)	/* File is in append mode. */

#define FILE_TYPE_SERIAL  (FILE_TYPE_PIPE+1)
#define FILE_TYPE_CONSOLE (FILE_TYPE_PIPE+2)

/*
 * The following structure contains per-instance data for a file based channel.
 */

typedef struct FileInfo {
    Tcl_Channel channel;	/* Pointer to channel structure. */
    int validMask;		/* OR'ed combination of TCL_READABLE,
				 * TCL_WRITABLE, or TCL_EXCEPTION: indicates
				 * which operations are valid on the file. */
    int watchMask;		/* OR'ed combination of TCL_READABLE,
				 * TCL_WRITABLE, or TCL_EXCEPTION: indicates
				 * which events should be reported. */
    int flags;			/* State flags, see above for a list. */
    HANDLE handle;		/* Input/output file. */
    struct FileInfo *nextPtr;	/* Pointer to next registered file. */
    int dirty;                  /* Boolean flag. Set if the OS may have data
				 * pending on the channel */
} FileInfo;

typedef struct ThreadSpecificData {
    /*
     * List of all file channels currently open.
     */

    FileInfo *firstFilePtr;
} ThreadSpecificData;

static Tcl_ThreadDataKey dataKey;

/*
 * The following structure is what is added to the Tcl event queue when
 * file events are generated.
 */

typedef struct FileEvent {
    Tcl_Event header;		/* Information that is standard for
				 * all events. */
    FileInfo *infoPtr;		/* Pointer to file info structure.  Note
				 * that we still have to verify that the
				 * file exists before dereferencing this
				 * pointer. */
} FileEvent;

/*
 * Static routines for this file:
 */

static int		FileBlockProc _ANSI_ARGS_((ClientData instanceData,
			    int mode));
static void		FileChannelExitHandler _ANSI_ARGS_((
		            ClientData clientData));
static void		FileCheckProc _ANSI_ARGS_((ClientData clientData,
			    int flags));
static int		FileCloseProc _ANSI_ARGS_((ClientData instanceData,
		            Tcl_Interp *interp));
static int		FileEventProc _ANSI_ARGS_((Tcl_Event *evPtr, 
			    int flags));
static int		FileGetHandleProc _ANSI_ARGS_((ClientData instanceData,
		            int direction, ClientData *handlePtr));
static ThreadSpecificData *FileInit _ANSI_ARGS_((void));
static int		FileInputProc _ANSI_ARGS_((ClientData instanceData,
	            	    char *buf, int toRead, int *errorCode));
static int		FileOutputProc _ANSI_ARGS_((ClientData instanceData,
			    CONST char *buf, int toWrite, int *errorCode));
static int		FileSeekProc _ANSI_ARGS_((ClientData instanceData,
			    long offset, int mode, int *errorCode));
static Tcl_WideInt	FileWideSeekProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_WideInt offset, int mode, int *errorCode));
static void		FileSetupProc _ANSI_ARGS_((ClientData clientData,
			    int flags));
static void		FileWatchProc _ANSI_ARGS_((ClientData instanceData,
		            int mask));

			    
/*
 * This structure describes the channel type structure for file based IO.
 */

static Tcl_ChannelType fileChannelType = {
    "file",			/* Type name. */
    TCL_CHANNEL_VERSION_3,	/* v3 channel */
    FileCloseProc,		/* Close proc. */
    FileInputProc,		/* Input proc. */
    FileOutputProc,		/* Output proc. */
    FileSeekProc,		/* Seek proc. */
    NULL,			/* Set option proc. */
    NULL,			/* Get option proc. */
    FileWatchProc,		/* Set up the notifier to watch the channel. */
    FileGetHandleProc,		/* Get an OS handle from channel. */
    NULL,			/* close2proc. */
    FileBlockProc,		/* Set blocking or non-blocking mode.*/
    NULL,			/* flush proc. */
    NULL,			/* handler proc. */
    FileWideSeekProc,		/* Wide seek proc. */
};

#ifdef HAVE_NO_SEH
static void *ESP __attribute__ ((used));
static void *EBP __attribute__ ((used));
#endif /* HAVE_NO_SEH */


/*
 *----------------------------------------------------------------------
 *
 * FileInit --
 *
 *	This function creates the window used to simulate file events.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Creates a new window and creates an exit handler. 
 *
 *----------------------------------------------------------------------
 */

static ThreadSpecificData *
FileInit()
{
    ThreadSpecificData *tsdPtr =
	(ThreadSpecificData *)TclThreadDataKeyGet(&dataKey);
    if (tsdPtr == NULL) {
	tsdPtr = TCL_TSD_INIT(&dataKey);
	tsdPtr->firstFilePtr = NULL;
	Tcl_CreateEventSource(FileSetupProc, FileCheckProc, NULL);
	Tcl_CreateThreadExitHandler(FileChannelExitHandler, NULL);
    }
    return tsdPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * FileChannelExitHandler --
 *
 *	This function is called to cleanup the channel driver before
 *	Tcl is unloaded.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Destroys the communication window.
 *
 *----------------------------------------------------------------------
 */

static void
FileChannelExitHandler(clientData)
    ClientData clientData;	/* Old window proc */
{
    Tcl_DeleteEventSource(FileSetupProc, FileCheckProc, NULL);
}

/*
 *----------------------------------------------------------------------
 *
 * FileSetupProc --
 *
 *	This procedure is invoked before Tcl_DoOneEvent blocks waiting
 *	for an event.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Adjusts the block time if needed.
 *
 *----------------------------------------------------------------------
 */

void
FileSetupProc(data, flags)
    ClientData data;		/* Not used. */
    int flags;			/* Event flags as passed to Tcl_DoOneEvent. */
{
    FileInfo *infoPtr;
    Tcl_Time blockTime = { 0, 0 };
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    if (!(flags & TCL_FILE_EVENTS)) {
	return;
    }
    
    /*
     * Check to see if there is a ready file.  If so, poll.
     */

    for (infoPtr = tsdPtr->firstFilePtr; infoPtr != NULL; 
	    infoPtr = infoPtr->nextPtr) {
	if (infoPtr->watchMask) {
	    Tcl_SetMaxBlockTime(&blockTime);
	    break;
	}
    }
}

/*
 *----------------------------------------------------------------------
 *
 * FileCheckProc --
 *
 *	This procedure is called by Tcl_DoOneEvent to check the file
 *	event source for events. 
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	May queue an event.
 *
 *----------------------------------------------------------------------
 */

static void
FileCheckProc(data, flags)
    ClientData data;		/* Not used. */
    int flags;			/* Event flags as passed to Tcl_DoOneEvent. */
{
    FileEvent *evPtr;
    FileInfo *infoPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    if (!(flags & TCL_FILE_EVENTS)) {
	return;
    }
    
    /*
     * Queue events for any ready files that don't already have events
     * queued (caused by persistent states that won't generate WinSock
     * events).
     */

    for (infoPtr = tsdPtr->firstFilePtr; infoPtr != NULL; 
	    infoPtr = infoPtr->nextPtr) {
	if (infoPtr->watchMask && !(infoPtr->flags & FILE_PENDING)) {
	    infoPtr->flags |= FILE_PENDING;
	    evPtr = (FileEvent *) ckalloc(sizeof(FileEvent));
	    evPtr->header.proc = FileEventProc;
	    evPtr->infoPtr = infoPtr;
	    Tcl_QueueEvent((Tcl_Event *) evPtr, TCL_QUEUE_TAIL);
	}
    }
}

/*----------------------------------------------------------------------
 *
 * FileEventProc --
 *
 *	This function is invoked by Tcl_ServiceEvent when a file event
 *	reaches the front of the event queue.  This procedure invokes
 *	Tcl_NotifyChannel on the file.
 *
 * Results:
 *	Returns 1 if the event was handled, meaning it should be removed
 *	from the queue.  Returns 0 if the event was not handled, meaning
 *	it should stay on the queue.  The only time the event isn't
 *	handled is if the TCL_FILE_EVENTS flag bit isn't set.
 *
 * Side effects:
 *	Whatever the notifier callback does.
 *
 *----------------------------------------------------------------------
 */

static int
FileEventProc(evPtr, flags)
    Tcl_Event *evPtr;		/* Event to service. */
    int flags;			/* Flags that indicate what events to
				 * handle, such as TCL_FILE_EVENTS. */
{
    FileEvent *fileEvPtr = (FileEvent *)evPtr;
    FileInfo *infoPtr;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    if (!(flags & TCL_FILE_EVENTS)) {
	return 0;
    }

    /*
     * Search through the list of watched files for the one whose handle
     * matches the event.  We do this rather than simply dereferencing
     * the handle in the event so that files can be deleted while the
     * event is in the queue.
     */

    for (infoPtr = tsdPtr->firstFilePtr; infoPtr != NULL;
	    infoPtr = infoPtr->nextPtr) {
	if (fileEvPtr->infoPtr == infoPtr) {
	    infoPtr->flags &= ~(FILE_PENDING);
	    Tcl_NotifyChannel(infoPtr->channel, infoPtr->watchMask);
	    break;
	}
    }
    return 1;
}

/*
 *----------------------------------------------------------------------
 *
 * FileBlockProc --
 *
 *	Set blocking or non-blocking mode on channel.
 *
 * Results:
 *	0 if successful, errno when failed.
 *
 * Side effects:
 *	Sets the device into blocking or non-blocking mode.
 *
 *----------------------------------------------------------------------
 */

static int
FileBlockProc(instanceData, mode)
    ClientData instanceData;	/* Instance data for channel. */
    int mode;			/* TCL_MODE_BLOCKING or
                                 * TCL_MODE_NONBLOCKING. */
{
    FileInfo *infoPtr = (FileInfo *) instanceData;
    
    /*
     * Files on Windows can not be switched between blocking and nonblocking,
     * hence we have to emulate the behavior. This is done in the input
     * function by checking against a bit in the state. We set or unset the
     * bit here to cause the input function to emulate the correct behavior.
     */

    if (mode == TCL_MODE_NONBLOCKING) {
	infoPtr->flags |= FILE_ASYNC;
    } else {
	infoPtr->flags &= ~(FILE_ASYNC);
    }
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * FileCloseProc --
 *
 *	Closes the IO channel.
 *
 * Results:
 *	0 if successful, the value of errno if failed.
 *
 * Side effects:
 *	Closes the physical channel
 *
 *----------------------------------------------------------------------
 */

static int
FileCloseProc(instanceData, interp)
    ClientData instanceData;	/* Pointer to FileInfo structure. */
    Tcl_Interp *interp;		/* Not used. */
{
    FileInfo *fileInfoPtr = (FileInfo *) instanceData;
    FileInfo **nextPtrPtr;
    int errorCode = 0;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    /*
     * Remove the file from the watch list.
     */

    FileWatchProc(instanceData, 0);

    /*
     * Don't close the Win32 handle if the handle is a standard channel
     * during the exit process.  Otherwise, one thread may kill the stdio
     * of another.
     */

    if (!TclInExit() 
	    || ((GetStdHandle(STD_INPUT_HANDLE) != fileInfoPtr->handle)
		&& (GetStdHandle(STD_OUTPUT_HANDLE) != fileInfoPtr->handle)
		&& (GetStdHandle(STD_ERROR_HANDLE) != fileInfoPtr->handle))) {
	if (CloseHandle(fileInfoPtr->handle) == FALSE) {
	    TclWinConvertError(GetLastError());
	    errorCode = errno;
	}
    }
    for (nextPtrPtr = &(tsdPtr->firstFilePtr); (*nextPtrPtr) != NULL;
	 nextPtrPtr = &((*nextPtrPtr)->nextPtr)) {
	if ((*nextPtrPtr) == fileInfoPtr) {
	    (*nextPtrPtr) = fileInfoPtr->nextPtr;
	    break;
	}
    }
    ckfree((char *)fileInfoPtr);
    return errorCode;
}

/*
 *----------------------------------------------------------------------
 *
 * FileSeekProc --
 *
 *	Seeks on a file-based channel. Returns the new position.
 *
 * Results:
 *	-1 if failed, the new position if successful. If failed, it
 *	also sets *errorCodePtr to the error code.
 *
 * Side effects:
 *	Moves the location at which the channel will be accessed in
 *	future operations.
 *
 *----------------------------------------------------------------------