tclunixchan.c

tcl是工具命令语言

/* 
 * tclUnixChan.c
 *
 *	Common channel driver for Unix channels based on files, command
 *	pipes and TCP sockets.
 *
 * Copyright (c) 1995-1997 Sun Microsystems, Inc.
 * Copyright (c) 1998-1999 by Scriptics Corporation.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclUnixChan.c,v 1.42 2003/02/21 02:36:27 hobbs Exp $
 */

#include "tclInt.h"	/* Internal definitions for Tcl. */
#include "tclPort.h"	/* Portability features for Tcl. */
#include "tclIO.h"	/* To get Channel type declaration. */

/*
 * sys/ioctl.h has already been included by tclPort.h.	Including termios.h
 * or termio.h causes a bunch of warning messages because some duplicate
 * (but not contradictory) #defines exist in termios.h and/or termio.h
 */
#undef NL0
#undef NL1
#undef CR0
#undef CR1
#undef CR2
#undef CR3
#undef TAB0
#undef TAB1
#undef TAB2
#undef XTABS
#undef BS0
#undef BS1
#undef FF0
#undef FF1
#undef ECHO
#undef NOFLSH
#undef TOSTOP
#undef FLUSHO
#undef PENDIN

#define SUPPORTS_TTY

#ifdef USE_TERMIOS
#   include <termios.h>
#   ifdef HAVE_SYS_IOCTL_H
#	include <sys/ioctl.h>
#   endif /* HAVE_SYS_IOCTL_H */
#   ifdef HAVE_SYS_MODEM_H
#	include <sys/modem.h>
#   endif /* HAVE_SYS_MODEM_H */
#   define IOSTATE			struct termios
#   define GETIOSTATE(fd, statePtr)	tcgetattr((fd), (statePtr))
#   define SETIOSTATE(fd, statePtr)	tcsetattr((fd), TCSADRAIN, (statePtr))
#   define GETCONTROL(fd, intPtr)	ioctl((fd), TIOCMGET, (intPtr))
#   define SETCONTROL(fd, intPtr)	ioctl((fd), TIOCMSET, (intPtr))
    /*
     * TIP #35 introduced a different on exit flush/close behavior that
     * doesn't work correctly with standard channels on all systems.
     * The problem is tcflush throws away waiting channel data.	 This may
     * be necessary for true serial channels that may block, but isn't
     * correct in the standard case.  This might be replaced with tcdrain
     * instead, but that can block.  For now, we revert to making this do
     * nothing, and TtyOutputProc being the same old FileOutputProc.
     * -- hobbs [Bug #525783]
     */
#   define BAD_TIP35_FLUSH 0
#   if BAD_TIP35_FLUSH
#	define TTYFLUSH(fd)		tcflush((fd), TCIOFLUSH);
#   else
#	define TTYFLUSH(fd)
#   endif /* BAD_TIP35_FLUSH */
#   ifdef FIONREAD
#	define GETREADQUEUE(fd, int)	ioctl((fd), FIONREAD, &(int))
#   elif defined(FIORDCHK)
#	define GETREADQUEUE(fd, int)	int = ioctl((fd), FIORDCHK, NULL)
#   endif /* FIONREAD */
#   ifdef TIOCOUTQ
#	define GETWRITEQUEUE(fd, int)	ioctl((fd), TIOCOUTQ, &(int))
#   endif /* TIOCOUTQ */
#   if defined(TIOCSBRK) && defined(TIOCCBRK)
/*
 * Can't use ?: operator below because that messes up types on either
 * Linux or Solaris (the two are mutually exclusive!)
 */
#	define SETBREAK(fd, flag) \
		if (flag) {				\
		    ioctl((fd), TIOCSBRK, NULL);	\
		} else {				\
		    ioctl((fd), TIOCCBRK, NULL);	\
		}
#   endif /* TIOCSBRK&TIOCCBRK */
#   if !defined(CRTSCTS) && defined(CNEW_RTSCTS)
#	define CRTSCTS CNEW_RTSCTS
#   endif /* !CRTSCTS&CNEW_RTSCTS */
#else	/* !USE_TERMIOS */

#ifdef USE_TERMIO
#   include <termio.h>
#   define IOSTATE			struct termio
#   define GETIOSTATE(fd, statePtr)	ioctl((fd), TCGETA, (statePtr))
#   define SETIOSTATE(fd, statePtr)	ioctl((fd), TCSETAW, (statePtr))
#else	/* !USE_TERMIO */

#ifdef USE_SGTTY
#   include <sgtty.h>
#   define IOSTATE			struct sgttyb
#   define GETIOSTATE(fd, statePtr)	ioctl((fd), TIOCGETP, (statePtr))
#   define SETIOSTATE(fd, statePtr)	ioctl((fd), TIOCSETP, (statePtr))
#else	/* !USE_SGTTY */
#   undef SUPPORTS_TTY
#endif	/* !USE_SGTTY */

#endif	/* !USE_TERMIO */
#endif	/* !USE_TERMIOS */

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

typedef struct FileState {
    Tcl_Channel channel;	/* Channel associated with this file. */
    int fd;			/* File handle. */
    int validMask;		/* OR'ed combination of TCL_READABLE,
				 * TCL_WRITABLE, or TCL_EXCEPTION: indicates
				 * which operations are valid on the file. */
#ifdef DEPRECATED
    struct FileState *nextPtr;	/* Pointer to next file in list of all
				 * file channels. */
#endif /* DEPRECATED */
} FileState;

#ifdef SUPPORTS_TTY

/*
 * The following structure describes per-instance state of a tty-based
 * channel.
 */

typedef struct TtyState {
    FileState fs;		/* Per-instance state of the file
				 * descriptor.	Must be the first field. */
    int stateUpdated;		/* Flag to say if the state has been
				 * modified and needs resetting. */
    IOSTATE savedState;		/* Initial state of device.  Used to reset
				 * state when device closed. */
} TtyState;

/*
 * The following structure is used to set or get the serial port
 * attributes in a platform-independant manner.
 */

typedef struct TtyAttrs {
    int baud;
    int parity;
    int data;
    int stop;
} TtyAttrs;

#endif	/* !SUPPORTS_TTY */

#define UNSUPPORTED_OPTION(detail) \
	if (interp) {							\
	    Tcl_AppendResult(interp, (detail),				\
		    " not supported for this platform", (char *) NULL); \
	}

#ifdef DEPRECATED
typedef struct ThreadSpecificData {
    /*
     * List of all file channels currently open.  This is per thread and is
     * used to match up fd's to channels, which rarely occurs.
     */

    FileState *firstFilePtr;
} ThreadSpecificData;

static Tcl_ThreadDataKey dataKey;
#endif /* DEPRECATED */

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

typedef struct TcpState {
    Tcl_Channel channel;	/* Channel associated with this file. */
    int fd;			/* The socket itself. */
    int flags;			/* ORed combination of the bitfields
				 * defined below. */
    Tcl_TcpAcceptProc *acceptProc;
				/* Proc to call on accept. */
    ClientData acceptProcData;	/* The data for the accept proc. */
} TcpState;

/*
 * These bits may be ORed together into the "flags" field of a TcpState
 * structure.
 */

#define TCP_ASYNC_SOCKET	(1<<0)	/* Asynchronous socket. */
#define TCP_ASYNC_CONNECT	(1<<1)	/* Async connect in progress. */

/*
 * The following defines the maximum length of the listen queue. This is
 * the number of outstanding yet-to-be-serviced requests for a connection
 * on a server socket, more than this number of outstanding requests and
 * the connection request will fail.
 */

#ifndef SOMAXCONN
#   define SOMAXCONN	100
#endif /* SOMAXCONN */

#if (SOMAXCONN < 100)
#   undef  SOMAXCONN
#   define SOMAXCONN	100
#endif /* SOMAXCONN < 100 */

/*
 * The following defines how much buffer space the kernel should maintain
 * for a socket.
 */

#define SOCKET_BUFSIZE	4096

/*
 * Static routines for this file:
 */

static TcpState *	CreateSocket _ANSI_ARGS_((Tcl_Interp *interp,
			    int port, CONST char *host, int server,
			    CONST char *myaddr, int myport, int async));
static int		CreateSocketAddress _ANSI_ARGS_(
			    (struct sockaddr_in *sockaddrPtr,
			    CONST char *host, int port));
static int		FileBlockModeProc _ANSI_ARGS_((
			    ClientData instanceData, int mode));
static int		FileCloseProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp));
static int		FileGetHandleProc _ANSI_ARGS_((ClientData instanceData,
			    int direction, ClientData *handlePtr));
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		FileWatchProc _ANSI_ARGS_((ClientData instanceData,
			    int mask));
static void		TcpAccept _ANSI_ARGS_((ClientData data, int mask));
static int		TcpBlockModeProc _ANSI_ARGS_((ClientData data,
			    int mode));
static int		TcpCloseProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp));
static int		TcpGetHandleProc _ANSI_ARGS_((ClientData instanceData,
			    int direction, ClientData *handlePtr));
static int		TcpGetOptionProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp, CONST char *optionName,
			    Tcl_DString *dsPtr));
static int		TcpInputProc _ANSI_ARGS_((ClientData instanceData,
			    char *buf, int toRead,  int *errorCode));
static int		TcpOutputProc _ANSI_ARGS_((ClientData instanceData,
			    CONST char *buf, int toWrite, int *errorCode));
static void		TcpWatchProc _ANSI_ARGS_((ClientData instanceData,
			    int mask));
#ifdef SUPPORTS_TTY
static int		TtyCloseProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp));
static void		TtyGetAttributes _ANSI_ARGS_((int fd,
			    TtyAttrs *ttyPtr));
static int		TtyGetOptionProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp, CONST char *optionName,
			    Tcl_DString *dsPtr));
static FileState *	TtyInit _ANSI_ARGS_((int fd, int initialize));
#if BAD_TIP35_FLUSH
static int		TtyOutputProc _ANSI_ARGS_((ClientData instanceData,
			    CONST char *buf, int toWrite, int *errorCode));
#endif /* BAD_TIP35_FLUSH */
static int		TtyParseMode _ANSI_ARGS_((Tcl_Interp *interp,
			    CONST char *mode, int *speedPtr, int *parityPtr,
			    int *dataPtr, int *stopPtr));
static void		TtySetAttributes _ANSI_ARGS_((int fd,
			    TtyAttrs *ttyPtr));
static int		TtySetOptionProc _ANSI_ARGS_((ClientData instanceData,
			    Tcl_Interp *interp, CONST char *optionName, 
			    CONST char *value));
#endif	/* SUPPORTS_TTY */
static int		WaitForConnect _ANSI_ARGS_((TcpState *statePtr,
			    int *errorCodePtr));
static Tcl_Channel	MakeTcpClientChannelMode _ANSI_ARGS_(
			    (ClientData tcpSocket,
			    int mode));


/*
 * 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,		/* Initialize notifier. */
    FileGetHandleProc,		/* Get OS handles out of channel. */
    NULL,			/* close2proc. */
    FileBlockModeProc,		/* Set blocking or non-blocking mode.*/
    NULL,			/* flush proc. */
    NULL,			/* handler proc. */
    FileWideSeekProc,		/* wide seek proc. */
};

#ifdef SUPPORTS_TTY
/*
 * This structure describes the channel type structure for serial IO.
 * Note that this type is a subclass of the "file" type.
 */

static Tcl_ChannelType ttyChannelType = {
    "tty",			/* Type name. */
    TCL_CHANNEL_VERSION_2,	/* v2 channel */
    TtyCloseProc,		/* Close proc. */
    FileInputProc,		/* Input proc. */
#if BAD_TIP35_FLUSH
    TtyOutputProc,		/* Output proc. */
#else /* !BAD_TIP35_FLUSH */
    FileOutputProc,		/* Output proc. */
#endif /* BAD_TIP35_FLUSH */
    NULL,			/* Seek proc. */
    TtySetOptionProc,		/* Set option proc. */
    TtyGetOptionProc,		/* Get option proc. */
    FileWatchProc,		/* Initialize notifier. */
    FileGetHandleProc,		/* Get OS handles out of channel. */
    NULL,			/* close2proc. */
    FileBlockModeProc,		/* Set blocking or non-blocking mode.*/
    NULL,			/* flush proc. */
    NULL,			/* handler proc. */
};
#endif	/* SUPPORTS_TTY */

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

static Tcl_ChannelType tcpChannelType = {
    "tcp",			/* Type name. */
    TCL_CHANNEL_VERSION_2,	/* v2 channel */
    TcpCloseProc,		/* Close proc. */
    TcpInputProc,		/* Input proc. */
    TcpOutputProc,		/* Output proc. */
    NULL,			/* Seek proc. */
    NULL,			/* Set option proc. */
    TcpGetOptionProc,		/* Get option proc. */
    TcpWatchProc,		/* Initialize notifier. */
    TcpGetHandleProc,		/* Get OS handles out of channel. */
    NULL,			/* close2proc. */
    TcpBlockModeProc,		/* Set blocking or non-blocking mode.*/
    NULL,			/* flush proc. */
    NULL,			/* handler proc. */
};


/*
 *----------------------------------------------------------------------
 *
 * FileBlockModeProc --
 *
 *	Helper procedure to set blocking and nonblocking modes on a
 *	file based channel. Invoked by generic IO level code.
 *
 * Results:
 *	0 if successful, errno when failed.
 *
 * Side effects:
 *	Sets the device into blocking or non-blocking mode.
 *
 *----------------------------------------------------------------------
 */

	/* ARGSUSED */
static int
FileBlockModeProc(instanceData, mode)
    ClientData instanceData;		/* File state. */
    int mode;				/* The mode to set. Can be one of
					 * TCL_MODE_BLOCKING or
					 * TCL_MODE_NONBLOCKING. */
{
    FileState *fsPtr = (FileState *) instanceData;
    int curStatus;

#ifndef USE_FIONBIO
    curStatus = fcntl(fsPtr->fd, F_GETFL);
    if (mode == TCL_MODE_BLOCKING) {
	curStatus &= (~(O_NONBLOCK));
    } else {
	curStatus |= O_NONBLOCK;
    }
    if (fcntl(fsPtr->fd, F_SETFL, curStatus) < 0) {
	return errno;
    }
    curStatus = fcntl(fsPtr->fd, F_GETFL);
#else /* USE_FIONBIO */
    if (mode == TCL_MODE_BLOCKING) {
	curStatus = 0;
    } else {
	curStatus = 1;
    }
    if (ioctl(fsPtr->fd, (int) FIONBIO, &curStatus) < 0) {
	return errno;
    }
#endif /* !USE_FIONBIO */
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * FileInputProc --
 *
 *	This procedure is invoked from the generic IO level to read
 *	input from a file based channel.
 *
 * Results:
 *	The number of bytes read is returned or -1 on error. An output
 *	argument contains a POSIX error code if an error occurs, or zero.
 *
 * Side effects:
 *	Reads input from the input device of the channel.
 *
 *----------------------------------------------------------------------
 */

static int
FileInputProc(instanceData, buf, toRead, errorCodePtr)
    ClientData instanceData;		/* File state. */
    char *buf;				/* Where to store data read. */
    int toRead;				/* How much space is available
					 * in the buffer? */
    int *errorCodePtr;			/* Where to store error code. */
{
    FileState *fsPtr = (FileState *) instanceData;
    int bytesRead;			/* How many bytes were actually
					 * read from the input device? */

    *errorCodePtr = 0;

    /*
     * Assume there is always enough input available. This will block
     * appropriately, and read will unblock as soon as a short read is
     * possible, if the channel is in blocking mode. If the channel is
     * nonblocking, the read will never block.
     */

    bytesRead = read(fsPtr->fd, buf, (size_t) toRead);
    if (bytesRead > -1) {
	return bytesRead;
    }
    *errorCodePtr = errno;
    return -1;
}

/*
 *----------------------------------------------------------------------
 *
 * FileOutputProc--
 *
 *	This procedure is invoked from the generic IO level to write
 *	output to a file channel.
 *
 * Results:
 *	The number of bytes written is returned or -1 on error. An
 *	output argument contains a POSIX error code if an error occurred,