tclwinconsole.c

这是leon3处理器的交叉编译链

/* 
 * tclWinConsole.c --
 *
 *	This file implements the Windows-specific console functions,
 *	and the "console" channel driver.
 *
 * Copyright (c) 1999 by Scriptics Corp.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclWinConsole.c,v 1.8 2002/09/02 19:27:02 hobbs Exp $
 */

#include "tclWinInt.h"

#include <fcntl.h>
#include <io.h>
#include <sys/stat.h>

/*
 * The following variable is used to tell whether this module has been
 * initialized.
 */

static int initialized = 0;

/*
 * The consoleMutex locks around access to the initialized variable, and it is
 * used to protect background threads from being terminated while they are
 * using APIs that hold locks.
 */

TCL_DECLARE_MUTEX(consoleMutex)

/*
 * Bit masks used in the flags field of the ConsoleInfo structure below.
 */

#define CONSOLE_PENDING	(1<<0)	/* Message is pending in the queue. */
#define CONSOLE_ASYNC	(1<<1)	/* Channel is non-blocking. */

/*
 * Bit masks used in the sharedFlags field of the ConsoleInfo structure below.
 */

#define CONSOLE_EOF	  (1<<2)  /* Console has reached EOF. */
#define CONSOLE_BUFFERED  (1<<3)  /* data was read into a buffer by the reader
				     thread */

#define CONSOLE_BUFFER_SIZE (8*1024)
/*
 * This structure describes per-instance data for a console based channel.
 */

typedef struct ConsoleInfo {
    HANDLE handle;
    int type;
    struct ConsoleInfo *nextPtr;/* Pointer to next registered console. */
    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. */
    Tcl_ThreadId threadId;	/* Thread to which events should be reported.
				 * This value is used by the reader/writer
				 * threads. */
    HANDLE writeThread;		/* Handle to writer thread. */
    HANDLE readThread;		/* Handle to reader thread. */
    HANDLE writable;		/* Manual-reset event to signal when the
				 * writer thread has finished waiting for
				 * the current buffer to be written. */
    HANDLE readable;		/* Manual-reset event to signal when the
				 * reader thread has finished waiting for
				 * input. */
    HANDLE startWriter;		/* Auto-reset event used by the main thread to
				 * signal when the writer thread should attempt
				 * to write to the console. */
    HANDLE startReader;		/* Auto-reset event used by the main thread to
				 * signal when the reader thread should attempt
				 * to read from the console. */
    DWORD writeError;		/* An error caused by the last background
				 * write.  Set to 0 if no error has been
				 * detected.  This word is shared with the
				 * writer thread so access must be
				 * synchronized with the writable object.
				 */
    char *writeBuf;		/* Current background output buffer.
				 * Access is synchronized with the writable
				 * object. */
    int writeBufLen;		/* Size of write buffer.  Access is
				 * synchronized with the writable
				 * object. */
    int toWrite;		/* Current amount to be written.  Access is
				 * synchronized with the writable object. */
    int readFlags;		/* Flags that are shared with the reader
				 * thread.  Access is synchronized with the
				 * readable object.  */
    int bytesRead;              /* number of bytes in the buffer */
    int offset;                 /* number of bytes read out of the buffer */
    char buffer[CONSOLE_BUFFER_SIZE];
                                /* Data consumed by reader thread. */
} ConsoleInfo;

typedef struct ThreadSpecificData {
    /*
     * The following pointer refers to the head of the list of consoles
     * that are being watched for file events.
     */
    
    ConsoleInfo *firstConsolePtr;
} ThreadSpecificData;

static Tcl_ThreadDataKey dataKey;

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

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

/*
 * Declarations for functions used only in this file.
 */

static int		ConsoleBlockModeProc(ClientData instanceData, int mode);
static void		ConsoleCheckProc(ClientData clientData, int flags);
static int		ConsoleCloseProc(ClientData instanceData,
			    Tcl_Interp *interp);
static int		ConsoleEventProc(Tcl_Event *evPtr, int flags);
static void		ConsoleExitHandler(ClientData clientData);
static int		ConsoleGetHandleProc(ClientData instanceData,
			    int direction, ClientData *handlePtr);
static ThreadSpecificData *ConsoleInit(void);
static int		ConsoleInputProc(ClientData instanceData, char *buf,
			    int toRead, int *errorCode);
static int		ConsoleOutputProc(ClientData instanceData,
			    CONST char *buf, int toWrite, int *errorCode);
static DWORD WINAPI	ConsoleReaderThread(LPVOID arg);
static void		ConsoleSetupProc(ClientData clientData, int flags);
static void		ConsoleWatchProc(ClientData instanceData, int mask);
static DWORD WINAPI	ConsoleWriterThread(LPVOID arg);
static void		ProcExitHandler(ClientData clientData);
static int		WaitForRead(ConsoleInfo *infoPtr, int blocking);

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

static Tcl_ChannelType consoleChannelType = {
    "console",			/* Type name. */
    TCL_CHANNEL_VERSION_2,	/* v2 channel */
    ConsoleCloseProc,		/* Close proc. */
    ConsoleInputProc,		/* Input proc. */
    ConsoleOutputProc,		/* Output proc. */
    NULL,			/* Seek proc. */
    NULL,			/* Set option proc. */
    NULL,			/* Get option proc. */
    ConsoleWatchProc,		/* Set up notifier to watch the channel. */
    ConsoleGetHandleProc,	/* Get an OS handle from channel. */
    NULL,			/* close2proc. */
    ConsoleBlockModeProc,	/* Set blocking or non-blocking mode.*/
    NULL,			/* flush proc. */
    NULL,			/* handler proc. */
};

/*
 *----------------------------------------------------------------------
 *
 * ConsoleInit --
 *
 *	This function initializes the static variables for this file.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Creates a new event source.
 *
 *----------------------------------------------------------------------
 */

static ThreadSpecificData *
ConsoleInit()
{
    ThreadSpecificData *tsdPtr;

    /*
     * Check the initialized flag first, then check again in the mutex.
     * This is a speed enhancement.
     */

    if (!initialized) {
	Tcl_MutexLock(&consoleMutex);
	if (!initialized) {
	    initialized = 1;
	    Tcl_CreateExitHandler(ProcExitHandler, NULL);
	}
	Tcl_MutexUnlock(&consoleMutex);
    }

    tsdPtr = (ThreadSpecificData *)TclThreadDataKeyGet(&dataKey);
    if (tsdPtr == NULL) {
	tsdPtr = TCL_TSD_INIT(&dataKey);
	tsdPtr->firstConsolePtr = NULL;
	Tcl_CreateEventSource(ConsoleSetupProc, ConsoleCheckProc, NULL);
	Tcl_CreateThreadExitHandler(ConsoleExitHandler, NULL);
    }
    return tsdPtr;
}

/*
 *----------------------------------------------------------------------
 *
 * ConsoleExitHandler --
 *
 *	This function is called to cleanup the console module before
 *	Tcl is unloaded.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Removes the console event source.
 *
 *----------------------------------------------------------------------
 */

static void
ConsoleExitHandler(
    ClientData clientData)	/* Old window proc */
{
    Tcl_DeleteEventSource(ConsoleSetupProc, ConsoleCheckProc, NULL);
}

/*
 *----------------------------------------------------------------------
 *
 * ProcExitHandler --
 *
 *	This function is called to cleanup the process list before
 *	Tcl is unloaded.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Resets the process list.
 *
 *----------------------------------------------------------------------
 */

static void
ProcExitHandler(
    ClientData clientData)	/* Old window proc */
{
    Tcl_MutexLock(&consoleMutex);
    initialized = 0;
    Tcl_MutexUnlock(&consoleMutex);
}

/*
 *----------------------------------------------------------------------
 *
 * ConsoleSetupProc --
 *
 *	This procedure is invoked before Tcl_DoOneEvent blocks waiting
 *	for an event.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Adjusts the block time if needed.
 *
 *----------------------------------------------------------------------
 */

void
ConsoleSetupProc(
    ClientData data,		/* Not used. */
    int flags)			/* Event flags as passed to Tcl_DoOneEvent. */
{
    ConsoleInfo *infoPtr;
    Tcl_Time blockTime = { 0, 0 };
    int block = 1;
    ThreadSpecificData *tsdPtr = TCL_TSD_INIT(&dataKey);

    if (!(flags & TCL_FILE_EVENTS)) {
	return;
    }
    
    /*
     * Look to see if any events are already pending.  If they are, poll.
     */

    for (infoPtr = tsdPtr->firstConsolePtr; infoPtr != NULL; 
	    infoPtr = infoPtr->nextPtr) {
	if (infoPtr->watchMask & TCL_WRITABLE) {
	    if (WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT) {
		block = 0;
	    }
	}
	if (infoPtr->watchMask & TCL_READABLE) {
	    if (WaitForRead(infoPtr, 0) >= 0) {
		block = 0;
	    }
	}
    }
    if (!block) {
	Tcl_SetMaxBlockTime(&blockTime);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * ConsoleCheckProc --
 *
 *	This procedure is called by Tcl_DoOneEvent to check the console
 *	event source for events. 
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	May queue an event.
 *
 *----------------------------------------------------------------------
 */

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

    if (!(flags & TCL_FILE_EVENTS)) {
	return;
    }
    
    /*
     * Queue events for any ready consoles that don't already have events
     * queued.
     */

    for (infoPtr = tsdPtr->firstConsolePtr; infoPtr != NULL; 
	    infoPtr = infoPtr->nextPtr) {
	if (infoPtr->flags & CONSOLE_PENDING) {
	    continue;
	}
	
	/*
	 * Queue an event if the console is signaled for reading or writing.
	 */

	needEvent = 0;
	if (infoPtr->watchMask & TCL_WRITABLE) {
	    if (WaitForSingleObject(infoPtr->writable, 0) != WAIT_TIMEOUT) {
		needEvent = 1;
	    }
	}
	
	if (infoPtr->watchMask & TCL_READABLE) {
	    if (WaitForRead(infoPtr, 0) >= 0) {
		needEvent = 1;
	    }
	}

	if (needEvent) {
	    infoPtr->flags |= CONSOLE_PENDING;
	    evPtr = (ConsoleEvent *) ckalloc(sizeof(ConsoleEvent));
	    evPtr->header.proc = ConsoleEventProc;
	    evPtr->infoPtr = infoPtr;
	    Tcl_QueueEvent((Tcl_Event *) evPtr, TCL_QUEUE_TAIL);
	}
    }
}


/*
 *----------------------------------------------------------------------
 *
 * ConsoleBlockModeProc --
 *
 *	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
ConsoleBlockModeProc(
    ClientData instanceData,	/* Instance data for channel. */
    int mode)			/* TCL_MODE_BLOCKING or
                                 * TCL_MODE_NONBLOCKING. */
{
    ConsoleInfo *infoPtr = (ConsoleInfo *) instanceData;
    
    /*
     * Consoles 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.