tclmacchan.c

linux系统下的音频通信

/* 
 * tclMacChan.c
 *
 *	Channel drivers for Macintosh channels for the
 *	console fds.
 *
 * Copyright (c) 1996-1997 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * SCCS: @(#) tclMacChan.c 1.43 97/06/20 11:27:48
 */

#include "tclInt.h"
#include "tclPort.h"
#include "tclMacInt.h"
#include <Aliases.h>
#include <Errors.h>
#include <Files.h>
#include <Gestalt.h>
#include <Processes.h>
#include <Strings.h>
#include <FSpCompat.h>
#include <MoreFiles.h>
#include <MoreFilesExtras.h>

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

static int initialized = 0;

/*
 * The following are flags returned by GetOpenMode.  They
 * are or'd together to determine how opening and handling
 * a file should occur.
 */

#define TCL_RDONLY		(1<<0)
#define TCL_WRONLY		(1<<1)
#define TCL_RDWR		(1<<2)
#define TCL_CREAT		(1<<3)
#define TCL_TRUNC		(1<<4)
#define TCL_APPEND		(1<<5)
#define TCL_ALWAYS_APPEND	(1<<6)
#define TCL_EXCL		(1<<7)
#define TCL_NOCTTY		(1<<8)
#define TCL_NONBLOCK		(1<<9)
#define TCL_RW_MODES 		(TCL_RDONLY|TCL_WRONLY|TCL_RDWR)

/*
 * This structure describes per-instance state of a 
 * macintosh file based channel.
 */

typedef struct FileState {
    short fileRef;		/* Macintosh file reference number. */
    Tcl_Channel fileChan;	/* Pointer to the channel for this file. */
    int watchMask;		/* OR'ed set of flags indicating which events
    				 * are being watched. */
    int appendMode;		/* Flag to tell if in O_APPEND mode or not. */
    int volumeRef;		/* Flag to tell if in O_APPEND mode or not. */
    int pending;		/* 1 if message is pending on queue. */
    struct FileState *nextPtr;	/* Pointer to next registered file. */
} FileState;

/*
 * The following pointer refers to the head of the list of files managed
 * that are being watched for file events.
 */

static FileState *firstFilePtr;

/*
 * 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. */
    FileState *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		CommonGetHandle _ANSI_ARGS_((ClientData instanceData,
		            int direction, ClientData *handlePtr));
static void		CommonWatch _ANSI_ARGS_((ClientData instanceData,
		            int mask));
static int		FileBlockMode _ANSI_ARGS_((ClientData instanceData,
			    int mode));
static void		FileChannelExitHandler _ANSI_ARGS_((
		            ClientData clientData));
static void		FileCheckProc _ANSI_ARGS_((ClientData clientData,
			    int flags));
static int		FileClose _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp));
static int		FileEventProc _ANSI_ARGS_((Tcl_Event *evPtr,
			    int flags));
static void		FileInit _ANSI_ARGS_((void));
static int		FileInput _ANSI_ARGS_((ClientData instanceData,
			    char *buf, int toRead, int *errorCode));
static int		FileOutput _ANSI_ARGS_((ClientData instanceData,
			    char *buf, int toWrite, int *errorCode));
static int		FileSeek _ANSI_ARGS_((ClientData instanceData,
			    long offset, int mode, int *errorCode));
static void		FileSetupProc _ANSI_ARGS_((ClientData clientData,
			    int flags));
static int		GetOpenMode _ANSI_ARGS_((Tcl_Interp *interp,
        		    char *string));
static Tcl_Channel	OpenFileChannel _ANSI_ARGS_((char *fileName, int mode, 
			    int permissions, int *errorCodePtr));
static int		StdIOBlockMode _ANSI_ARGS_((ClientData instanceData,
			    int mode));
static int		StdIOClose _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp));
static int		StdIOInput _ANSI_ARGS_((ClientData instanceData,
			    char *buf, int toRead, int *errorCode));
static int		StdIOOutput _ANSI_ARGS_((ClientData instanceData,
			    char *buf, int toWrite, int *errorCode));
static int		StdIOSeek _ANSI_ARGS_((ClientData instanceData,
			    long offset, int mode, int *errorCode));
static int		StdReady _ANSI_ARGS_((ClientData instanceData,
		            int mask));

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

static Tcl_ChannelType consoleChannelType = {
    "file",			/* Type name. */
    StdIOBlockMode,		/* Set blocking/nonblocking mode.*/
    StdIOClose,			/* Close proc. */
    StdIOInput,			/* Input proc. */
    StdIOOutput,		/* Output proc. */
    StdIOSeek,			/* Seek proc. */
    NULL,			/* Set option proc. */
    NULL,			/* Get option proc. */
    CommonWatch,		/* Initialize notifier. */
    CommonGetHandle		/* Get OS handles out of channel. */
};

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

static Tcl_ChannelType fileChannelType = {
    "file",			/* Type name. */
    FileBlockMode,		/* Set blocking or
                                 * non-blocking mode.*/
    FileClose,			/* Close proc. */
    FileInput,			/* Input proc. */
    FileOutput,			/* Output proc. */
    FileSeek,			/* Seek proc. */
    NULL,			/* Set option proc. */
    NULL,			/* Get option proc. */
    CommonWatch,		/* Initialize notifier. */
    CommonGetHandle		/* Get OS handles out of channel. */
};


/*
 * Hack to allow Mac Tk to override the TclGetStdChannels function.
 */
 
typedef void (*TclGetStdChannelsProc) _ANSI_ARGS_((Tcl_Channel *stdinPtr,
	Tcl_Channel *stdoutPtr, Tcl_Channel *stderrPtr));
	
TclGetStdChannelsProc getStdChannelsProc = NULL;

/*
 * Static variables to hold channels for stdin, stdout and stderr.
 */

static Tcl_Channel stdinChannel = NULL;
static Tcl_Channel stdoutChannel = NULL;
static Tcl_Channel stderrChannel = NULL;

/*
 *----------------------------------------------------------------------
 *
 * FileInit --
 *
 *	This function initializes the file channel event source.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Creates a new event source.
 *
 *----------------------------------------------------------------------
 */

static void
FileInit()
{
    initialized = 1;
    firstFilePtr = NULL;
    Tcl_CreateEventSource(FileSetupProc, FileCheckProc, NULL);
    Tcl_CreateExitHandler(FileChannelExitHandler, NULL);
}

/*
 *----------------------------------------------------------------------
 *
 * 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)	/* Old window proc */
{
    Tcl_DeleteEventSource(FileSetupProc, FileCheckProc, NULL);
    initialized = 0;
}

/*
 *----------------------------------------------------------------------
 *
 * 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(
    ClientData data,		/* Not used. */
    int flags)			/* Event flags as passed to Tcl_DoOneEvent. */
{
    FileState *infoPtr;
    Tcl_Time blockTime = { 0, 0 };

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

    for (infoPtr = 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(
    ClientData data,		/* Not used. */
    int flags)			/* Event flags as passed to Tcl_DoOneEvent. */
{
    FileEvent *evPtr;
    FileState *infoPtr;
    int sentMsg = 0;
    Tcl_Time blockTime = { 0, 0 };

    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 = firstFilePtr; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
	if (infoPtr->watchMask && !infoPtr->pending) {
	    infoPtr->pending = 1;
	    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(
    Tcl_Event *evPtr,		/* Event to service. */
    int flags)			/* Flags that indicate what events to
				 * handle, such as TCL_FILE_EVENTS. */
{
    FileEvent *fileEvPtr = (FileEvent *)evPtr;
    FileState *infoPtr;

    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 = firstFilePtr; infoPtr != NULL; infoPtr = infoPtr->nextPtr) {
	if (fileEvPtr->infoPtr == infoPtr) {
	    infoPtr->pending = 0;
	    Tcl_NotifyChannel(infoPtr->fileChan, infoPtr->watchMask);
	    break;
	}
    }
    return 1;
}

/*
 *----------------------------------------------------------------------
 *
 * StdIOBlockMode --
 *
 *	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
StdIOBlockMode(
    ClientData instanceData,		/* Unused. */
    int mode)				/* The mode to set. */
{
    /*
     * Do not allow putting stdin, stdout or stderr into nonblocking mode.
     */
    
    if (mode == TCL_MODE_NONBLOCKING) {
	return EFAULT;
    }
    
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * StdIOClose --
 *
 *	Closes the IO channel.
 *
 * Results:
 *	0 if successful, the value of errno if failed.
 *
 * Side effects:
 *	Closes the physical channel
 *
 *----------------------------------------------------------------------
 */

static int
StdIOClose(
    ClientData instanceData,	/* Unused. */
    Tcl_Interp *interp)		/* Unused. */
{
    int fd, errorCode = 0;

    /*
     * Invalidate the stdio cache if necessary.  Note that we assume that
     * the stdio file and channel pointers will become invalid at the same
     * time.
     */

    fd = (int) ((FileState*)instanceData)->fileRef;
    if (fd == 0) {
	fd = 0;
	stdinChannel = NULL;
    } else if (fd == 1) {
	stdoutChannel = NULL;
    } else if (fd == 2) {
	stderrChannel = NULL;
    } else {
	panic("recieved invalid std file");
    }

    if (close(fd) < 0) {
	errorCode = errno;
    }