xref: /xsrc/external/mit/libX11/dist/src/XlibInt.c

/*

Copyright 1985, 1986, 1987, 1998  The Open Group

Permission to use, copy, modify, distribute, and sell this software and its
documentation for any purpose is hereby granted without fee, provided that
the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation.

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall
not be used in advertising or otherwise to promote the sale, use or
other dealings in this Software without prior written authorization
from The Open Group.

*/

/*
 *	XlibInt.c - Internal support routines for the C subroutine
 *	interface library (Xlib) to the X Window System Protocol V11.0.
 */
#define NEED_EVENTS
#define NEED_REPLIES

#ifdef WIN32
#define _XLIBINT_
#endif
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "Xlibint.h"
#include "Xprivate.h"
#include <X11/Xpoll.h>
#if !USE_XCB
#include <X11/Xtrans/Xtrans.h>
#include <X11/extensions/xcmiscstr.h>
#endif /* !USE_XCB */
#include <assert.h>
#include <stdio.h>
#ifdef WIN32
#include <direct.h>
#endif

#ifdef XTHREADS
#include "locking.h"

/* these pointers get initialized by XInitThreads */
LockInfoPtr _Xglobal_lock = NULL;
void (*_XCreateMutex_fn)(LockInfoPtr) = NULL;
/* struct _XCVList *(*_XCreateCVL_fn)() = NULL; */
void (*_XFreeMutex_fn)(LockInfoPtr) = NULL;
void (*_XLockMutex_fn)(
    LockInfoPtr /* lock */
#if defined(XTHREADS_WARN) || defined(XTHREADS_FILE_LINE)
    , char * /* file */
    , int /* line */
#endif
    ) = NULL;
void (*_XUnlockMutex_fn)(
    LockInfoPtr /* lock */
#if defined(XTHREADS_WARN) || defined(XTHREADS_FILE_LINE)
    , char * /* file */
    , int /* line */
#endif
    ) = NULL;
xthread_t (*_Xthread_self_fn)(void) = NULL;

#define XThread_Self()	((*_Xthread_self_fn)())

#if !USE_XCB
#define UnlockNextReplyReader(d) if ((d)->lock) \
    (*(d)->lock->pop_reader)((d),&(d)->lock->reply_awaiters,&(d)->lock->reply_awaiters_tail)

#define QueueReplyReaderLock(d) ((d)->lock ? \
    (*(d)->lock->push_reader)(d,&(d)->lock->reply_awaiters_tail) : NULL)
#define QueueEventReaderLock(d) ((d)->lock ? \
    (*(d)->lock->push_reader)(d,&(d)->lock->event_awaiters_tail) : NULL)
#endif /* !USE_XCB */

#else /* XTHREADS else */

#if !USE_XCB
#define UnlockNextReplyReader(d)
#define UnlockNextEventReader(d)
#endif /* !USE_XCB */

#endif /* XTHREADS else */

/* check for both EAGAIN and EWOULDBLOCK, because some supposedly POSIX
 * systems are broken and return EWOULDBLOCK when they should return EAGAIN
 */
#ifdef WIN32
#define ETEST() (WSAGetLastError() == WSAEWOULDBLOCK)
#else
#ifdef __CYGWIN__ /* Cygwin uses ENOBUFS to signal socket is full */
#define ETEST() (errno == EAGAIN || errno == EWOULDBLOCK || errno == ENOBUFS)
#else
#if defined(EAGAIN) && defined(EWOULDBLOCK)
#define ETEST() (errno == EAGAIN || errno == EWOULDBLOCK)
#else
#ifdef EAGAIN
#define ETEST() (errno == EAGAIN)
#else
#define ETEST() (errno == EWOULDBLOCK)
#endif /* EAGAIN */
#endif /* EAGAIN && EWOULDBLOCK */
#endif /* __CYGWIN__ */
#endif /* WIN32 */

#ifdef WIN32
#define ECHECK(err) (WSAGetLastError() == err)
#define ESET(val) WSASetLastError(val)
#else
#ifdef __UNIXOS2__
#define ECHECK(err) (errno == err)
#define ESET(val)
#else
#define ECHECK(err) (errno == err)
#define ESET(val) errno = val
#endif
#endif

#if defined(LOCALCONN) || defined(LACHMAN)
#ifdef EMSGSIZE
#define ESZTEST() (ECHECK(EMSGSIZE) || ECHECK(ERANGE))
#else
#define ESZTEST() ECHECK(ERANGE)
#endif
#else
#ifdef EMSGSIZE
#define ESZTEST() ECHECK(EMSGSIZE)
#endif
#endif

#ifdef __UNIXOS2__
#if !USE_XCB
#define select(n,r,w,x,t) os2ClientSelect(n,r,w,x,t)
#endif /* !USE_XCB */
#include <limits.h>
#define MAX_PATH _POSIX_PATH_MAX
#endif

#if !USE_XCB
#ifdef MUSTCOPY

#define STARTITERATE(tpvar,type,start,endcond) \
  { register char *cpvar; \
  for (cpvar = (char *) (start); endcond; ) { \
    type dummy; memcpy ((char *) &dummy, cpvar, SIZEOF(type)); \
    tpvar = &dummy;
#define ITERPTR(tpvar) cpvar
#define RESETITERPTR(tpvar,type,start) cpvar = start
#define INCITERPTR(tpvar,type) cpvar += SIZEOF(type)
#define ENDITERATE }}

#else

#define STARTITERATE(tpvar,type,start,endcond) \
  for (tpvar = (type *) (start); endcond; )
#define ITERPTR(tpvar) (char *)tpvar
#define RESETITERPTR(tpvar,type,start) tpvar = (type *) (start)
#define INCITERPTR(tpvar,type) tpvar++
#define ENDITERATE

#endif /* MUSTCOPY */

typedef union {
    xReply rep;
    char buf[BUFSIZE];
} _XAlignedBuffer;

static char *_XAsyncReply(
    Display *dpy,
    register xReply *rep,
    char *buf,
    register int *lenp,
    Bool discard);
#endif /* !USE_XCB */

/*
 * The following routines are internal routines used by Xlib for protocol
 * packet transmission and reception.
 *
 * _XIOError(Display *) will be called if any sort of system call error occurs.
 * This is assumed to be a fatal condition, i.e., XIOError should not return.
 *
 * _XError(Display *, xError *) will be called whenever an X_Error event is
 * received.  This is not assumed to be a fatal condition, i.e., it is
 * acceptable for this procedure to return.  However, XError should NOT
 * perform any operations (directly or indirectly) on the DISPLAY.
 *
 * Routines declared with a return type of 'Status' return 0 on failure,
 * and non 0 on success.  Routines with no declared return type don't
 * return anything.  Whenever possible routines that create objects return
 * the object they have created.
 */

#if !USE_XCB
static xReq _dummy_request = {
	0, 0, 0
};

/*
 * This is an OS dependent routine which:
 * 1) returns as soon as the connection can be written on....
 * 2) if the connection can be read, must enqueue events and handle errors,
 * until the connection is writable.
 */
static void
_XWaitForWritable(
    Display *dpy
#ifdef XTHREADS
    ,
    xcondition_t cv		/* our reading condition variable */
#endif
    )
{
#ifdef USE_POLL
    struct pollfd filedes;
#else
    fd_set r_mask;
    fd_set w_mask;
#endif
    int nfound;

#ifdef USE_POLL
    filedes.fd = dpy->fd;
    filedes.events = 0;
#else
    FD_ZERO(&r_mask);
    FD_ZERO(&w_mask);
#endif

    for (;;) {
#ifdef XTHREADS
	/* We allow only one thread at a time to read, to minimize
	   passing of read data between threads.
	   Now, who is it?  If there is a non-NULL reply_awaiters and
	   we (i.e., our cv) are not at the head of it, then whoever
	   is at the head is the reader, and we don't read.
	   Otherwise there is no reply_awaiters or we are at the
	   head, having just appended ourselves.
	   In this case, if there is a event_awaiters, then whoever
	   is at the head of it got there before we did, and they are the
	   reader.

	   Last cases: no event_awaiters and we are at the head of
	   reply_awaiters or reply_awaiters is NULL: we are the reader,
	   since there is obviously no one else involved.

	   XXX - what if cv is NULL and someone else comes along after
	   us while we are waiting?
	   */

	if (!dpy->lock ||
	    (!dpy->lock->event_awaiters &&
	     (!dpy->lock->reply_awaiters ||
	      dpy->lock->reply_awaiters->cv == cv)))
#endif
#ifdef USE_POLL
	    filedes.events = POLLIN;
	filedes.events |= POLLOUT;
#else
	FD_SET(dpy->fd, &r_mask);
        FD_SET(dpy->fd, &w_mask);
#endif

	do {
	    UnlockDisplay(dpy);
#ifdef USE_POLL
	    nfound = poll (&filedes, 1, -1);
#else
	    nfound = Select (dpy->fd + 1, &r_mask, &w_mask, NULL, NULL);
#endif
	    InternalLockDisplay(dpy, cv != NULL);
	    if (nfound < 0 && !(ECHECK(EINTR) || ETEST()))
		_XIOError(dpy);
	} while (nfound <= 0);

	if (
#ifdef USE_POLL
	    filedes.revents & POLLIN
#else
	    FD_ISSET(dpy->fd, &r_mask)
#endif
	    )
	{
	    _XAlignedBuffer buf;
	    BytesReadable_t pend;
	    register int len;
	    register xReply *rep;

	    /* find out how much data can be read */
	    if (_X11TransBytesReadable(dpy->trans_conn, &pend) < 0)
		_XIOError(dpy);
	    len = pend;

	    /* must read at least one xEvent; if none is pending, then
	       we'll just block waiting for it */
	    if (len < SIZEOF(xReply)
#ifdef XTHREADS
		|| dpy->async_handlers
#endif
		)
		len = SIZEOF(xReply);

	    /* but we won't read more than the max buffer size */
	    if (len > BUFSIZE) len = BUFSIZE;

	    /* round down to an integral number of XReps */
	    len = (len / SIZEOF(xReply)) * SIZEOF(xReply);

	    (void) _XRead (dpy, buf.buf, (long) len);

	    STARTITERATE(rep,xReply,buf.buf,len > 0) {
		if (rep->generic.type == X_Reply) {
                    int tmp = len;
		    RESETITERPTR(rep,xReply,
				 _XAsyncReply (dpy, rep,
					       ITERPTR(rep), &tmp, True));
                    len = tmp;
		    pend = len;
		} else {
		    if (rep->generic.type == X_Error)
			_XError (dpy, (xError *)rep);
		    else	/* must be an event packet */
			_XEnq (dpy, (xEvent *)rep);
		    INCITERPTR(rep,xReply);
		    len -= SIZEOF(xReply);
		}
	    } ENDITERATE
#ifdef XTHREADS
	    if (dpy->lock && dpy->lock->event_awaiters)
		ConditionSignal(dpy, dpy->lock->event_awaiters->cv);
#endif
	}
#ifdef USE_POLL
	if (filedes.revents & (POLLOUT|POLLHUP|POLLERR))
#else
	if (FD_ISSET(dpy->fd, &w_mask))
#endif
	{
#ifdef XTHREADS
	    if (dpy->lock) {
		ConditionBroadcast(dpy, dpy->lock->writers);
	    }
#endif
	    return;
	}
    }
}
#endif /* !USE_XCB */


#define POLLFD_CACHE_SIZE 5

/* initialize the struct array passed to poll() below */
Bool _XPollfdCacheInit(
    Display *dpy)
{
#ifdef USE_POLL
    struct pollfd *pfp;

    pfp = (struct pollfd *)Xmalloc(POLLFD_CACHE_SIZE * sizeof(struct pollfd));
    if (!pfp)
	return False;
    pfp[0].fd = dpy->fd;
    pfp[0].events = POLLIN;

    dpy->filedes = (XPointer)pfp;
#endif
    return True;
}

void _XPollfdCacheAdd(
    Display *dpy,
    int fd)
{
#ifdef USE_POLL
    struct pollfd *pfp = (struct pollfd *)dpy->filedes;

    if (dpy->im_fd_length <= POLLFD_CACHE_SIZE) {
	pfp[dpy->im_fd_length].fd = fd;
	pfp[dpy->im_fd_length].events = POLLIN;
    }
#endif
}

/* ARGSUSED */
void _XPollfdCacheDel(
    Display *dpy,
    int fd)			/* not used */
{
#ifdef USE_POLL
    struct pollfd *pfp = (struct pollfd *)dpy->filedes;
    struct _XConnectionInfo *conni;

    /* just recalculate whole list */
    if (dpy->im_fd_length <= POLLFD_CACHE_SIZE) {
	int loc = 1;
	for (conni = dpy->im_fd_info; conni; conni=conni->next) {
	    pfp[loc].fd = conni->fd;
	    pfp[loc].events = POLLIN;
	    loc++;
	}
    }
#endif
}

#if !USE_XCB
/* returns True iff there is an event in the queue newer than serial_num */

static Bool
_XNewerQueuedEvent(
    Display *dpy,
    int serial_num)
{
    _XQEvent *qev;

    if (dpy->next_event_serial_num == serial_num)
	return False;

    qev = dpy->head;
    while (qev) {
	if (qev->qserial_num >= serial_num) {
	    return True;
	}
	qev = qev->next;
    }
    return False;
}

static int
_XWaitForReadable(
  Display *dpy)
{
    int result;
    int fd = dpy->fd;
    struct _XConnectionInfo *ilist;
    register int saved_event_serial = 0;
    int in_read_events = 0;
    register Bool did_proc_conni = False;
#ifdef USE_POLL
    struct pollfd *filedes;
#else
    fd_set r_mask;
    int highest_fd = fd;
#endif

#ifdef USE_POLL
    if (dpy->im_fd_length + 1 > POLLFD_CACHE_SIZE
	&& !(dpy->flags & XlibDisplayProcConni)) {
	/* XXX - this fallback is gross */
	int i;

	filedes = (struct pollfd *)Xmalloc(dpy->im_fd_length * sizeof(struct pollfd));
	filedes[0].fd = fd;
	filedes[0].events = POLLIN;
	for (ilist=dpy->im_fd_info, i=1; ilist; ilist=ilist->next, i++) {
	    filedes[i].fd = ilist->fd;
	    filedes[i].events = POLLIN;
	}
    } else {
	filedes = (struct pollfd *)dpy->filedes;
    }
#else
    FD_ZERO(&r_mask);
#endif
    for (;;) {
#ifndef USE_POLL
	FD_SET(fd, &r_mask);
	if (!(dpy->flags & XlibDisplayProcConni))
	    for (ilist=dpy->im_fd_info; ilist; ilist=ilist->next) {
		FD_SET(ilist->fd, &r_mask);
		if (ilist->fd > highest_fd)
		    highest_fd = ilist->fd;
	    }
#endif
	UnlockDisplay(dpy);
#ifdef USE_POLL
	result = poll(filedes,
		      (dpy->flags & XlibDisplayProcConni) ? 1 : 1+dpy->im_fd_length,
		      -1);
#else
	result = Select(highest_fd + 1, &r_mask, NULL, NULL, NULL);
#endif
	InternalLockDisplay(dpy, dpy->flags & XlibDisplayReply);
	if (result == -1 && !(ECHECK(EINTR) || ETEST())) _XIOError(dpy);
	if (result <= 0)
	    continue;
#ifdef USE_POLL
	if (filedes[0].revents & (POLLIN|POLLHUP|POLLERR))
#else
	if (FD_ISSET(fd, &r_mask))
#endif
	    break;
	if (!(dpy->flags & XlibDisplayProcConni)) {
	    int i;

	    saved_event_serial = dpy->next_event_serial_num;
	    /* dpy flags can be clobbered by internal connection callback */
	    in_read_events = dpy->flags & XlibDisplayReadEvents;
	    for (ilist=dpy->im_fd_info, i=1; ilist; ilist=ilist->next, i++) {
#ifdef USE_POLL
		if (filedes[i].revents & POLLIN)
#else
		if (FD_ISSET(ilist->fd, &r_mask))
#endif
		{
		    _XProcessInternalConnection(dpy, ilist);
		    did_proc_conni = True;
		}
	    }
#ifdef USE_POLL
	    if (dpy->im_fd_length + 1 > POLLFD_CACHE_SIZE)
		Xfree(filedes);
#endif
	}
	if (did_proc_conni) {
	    /* some internal connection callback might have done an
	       XPutBackEvent.  We notice it here and if we needed an event,
	       we can return all the way. */
	    if (_XNewerQueuedEvent(dpy, saved_event_serial)
		&& (in_read_events
#ifdef XTHREADS
		    || (dpy->lock && dpy->lock->event_awaiters)
#endif
		    ))
		return -2;
	    did_proc_conni = False;
	}
    }
#ifdef XTHREADS
#ifdef XTHREADS_DEBUG
    printf("thread %x _XWaitForReadable returning\n", XThread_Self());
#endif
#endif
    return 0;
}
#endif /* !USE_XCB */

static int sync_hazard(Display *dpy)
{
    unsigned long span = dpy->request - dpy->last_request_read;
    unsigned long hazard = min((dpy->bufmax - dpy->buffer) / SIZEOF(xReq), 65535 - 10);
    return span >= 65535 - hazard - 10;
}

static
void sync_while_locked(Display *dpy)
{
#ifdef XTHREADS
    if (dpy->lock)
        (*dpy->lock->user_lock_display)(dpy);
#endif
    UnlockDisplay(dpy);
    SyncHandle();
    InternalLockDisplay(dpy, /* don't skip user locks */ 0);
#ifdef XTHREADS
    if (dpy->lock)
        (*dpy->lock->user_unlock_display)(dpy);
#endif
}

void _XSeqSyncFunction(
    register Display *dpy)
{
    xGetInputFocusReply rep;
    register xReq *req;

    if ((dpy->request - dpy->last_request_read) >= (65535 - BUFSIZE/SIZEOF(xReq))) {
	GetEmptyReq(GetInputFocus, req);
	(void) _XReply (dpy, (xReply *)&rep, 0, xTrue);
	sync_while_locked(dpy);
    } else if (sync_hazard(dpy))
	_XSetPrivSyncFunction(dpy);
}

/* NOTE: only called if !XTHREADS, or when XInitThreads wasn't called. */
static int
_XPrivSyncFunction (Display *dpy)
{
#if XTHREADS
    assert(!dpy->lock_fns);
#endif
    assert(dpy->synchandler == _XPrivSyncFunction);
    assert((dpy->flags & XlibDisplayPrivSync) != 0);
    dpy->synchandler = dpy->savedsynchandler;
    dpy->savedsynchandler = NULL;
    dpy->flags &= ~XlibDisplayPrivSync;
    if(dpy->synchandler)
        dpy->synchandler(dpy);
    _XIDHandler(dpy);
    _XSeqSyncFunction(dpy);
    return 0;
}

void _XSetPrivSyncFunction(Display *dpy)
{
#ifdef XTHREADS
    if (dpy->lock_fns)
        return;
#endif
    if (!(dpy->flags & XlibDisplayPrivSync)) {
	dpy->savedsynchandler = dpy->synchandler;
	dpy->synchandler = _XPrivSyncFunction;
	dpy->flags |= XlibDisplayPrivSync;
    }
}

void _XSetSeqSyncFunction(Display *dpy)
{
    if (sync_hazard(dpy))
	_XSetPrivSyncFunction (dpy);
}

#if !USE_XCB
#ifdef XTHREADS
static void _XFlushInt(
        register Display *dpy,
        register xcondition_t cv);
#endif

/*
 * _XFlush - Flush the X request buffer.  If the buffer is empty, no
 * action is taken.  This routine correctly handles incremental writes.
 * This routine may have to be reworked if int < long.
 */
void _XFlush(
	register Display *dpy)
{
#ifdef XTHREADS
    /* With multi-threading we introduce an internal routine to which
       we can pass a condition variable to do locking correctly. */

    _XFlushInt(dpy, NULL);
}

/* _XFlushInt - Internal version of _XFlush used to do multi-threaded
 * locking correctly.
 */

static void _XFlushInt(
	register Display *dpy,
        register xcondition_t cv)
{
#endif /* XTHREADS*/
	register long size, todo;
	register int write_stat;
	register char *bufindex;
	_XExtension *ext;

	/* This fix resets the bufptr to the front of the buffer so
	 * additional appends to the bufptr will not corrupt memory. Since
	 * the server is down, these appends are no-op's anyway but
	 * callers of _XFlush() are not verifying this before they call it.
	 */
	if (dpy->flags & XlibDisplayIOError)
	{
	    dpy->bufptr = dpy->buffer;
	    dpy->last_req = (char *)&_dummy_request;
	    return;
	}

#ifdef XTHREADS
	while (dpy->flags & XlibDisplayWriting) {
	    if (dpy->lock) {
		ConditionWait(dpy, dpy->lock->writers);
	    } else {
		_XWaitForWritable (dpy, cv);
	    }
	}
#endif
	size = todo = dpy->bufptr - dpy->buffer;
	if (!size) return;
#ifdef XTHREADS
	dpy->flags |= XlibDisplayWriting;
	/* make sure no one else can put in data */
	dpy->bufptr = dpy->bufmax;
#endif
	for (ext = dpy->flushes; ext; ext = ext->next_flush)
	    (*ext->before_flush)(dpy, &ext->codes, dpy->buffer, size);
	bufindex = dpy->buffer;
	/*
	 * While write has not written the entire buffer, keep looping
	 * until the entire buffer is written.  bufindex will be
	 * incremented and size decremented as buffer is written out.
	 */
	while (size) {
	    ESET(0);
	    write_stat = _X11TransWrite(dpy->trans_conn,
					bufindex, (int) todo);
	    if (write_stat >= 0) {
		size -= write_stat;
		todo = size;
		bufindex += write_stat;
	    } else if (ETEST()) {
		_XWaitForWritable(dpy
#ifdef XTHREADS
				  , cv
#endif
				  );
#ifdef SUNSYSV
	    } else if (ECHECK(0)) {
		_XWaitForWritable(dpy
#ifdef XTHREADS
				  , cv
#endif
				  );
#endif
#ifdef ESZTEST
	    } else if (ESZTEST()) {
		if (todo > 1)
		    todo >>= 1;
		else {
		    _XWaitForWritable(dpy
#ifdef XTHREADS
				      , cv
#endif
				      );
		}
#endif
	    } else if (!ECHECK(EINTR)) {
		/* Write failed! */
		/* errno set by write system call. */
		_XIOError(dpy);
	    }
	}
	dpy->last_req = (char *)&_dummy_request;
	_XSetSeqSyncFunction(dpy);
	dpy->bufptr = dpy->buffer;
#ifdef XTHREADS
	dpy->flags &= ~XlibDisplayWriting;
#endif
}

int
_XEventsQueued(
    register Display *dpy,
    int mode)
{
	register int len;
	BytesReadable_t pend;
	_XAlignedBuffer buf;
	register xReply *rep;
	char *read_buf;
#ifdef XTHREADS
	int entry_event_serial_num;
	struct _XCVList *cvl = NULL;
	xthread_t self;

#ifdef XTHREADS_DEBUG
	printf("_XEventsQueued called in thread %x\n", XThread_Self());
#endif
#endif /* XTHREADS*/

	if (mode == QueuedAfterFlush)
	{
	    _XFlush(dpy);
	    if (dpy->qlen)
		return(dpy->qlen);
	}
	if (dpy->flags & XlibDisplayIOError) return(dpy->qlen);

#ifdef XTHREADS
	/* create our condition variable and append to list,
	 * unless we were called from within XProcessInternalConnection
	 * or XLockDisplay
	 */
	xthread_clear_id(self);
	if (dpy->lock && (xthread_have_id (dpy->lock->conni_thread)
			  || xthread_have_id (dpy->lock->locking_thread)))
	    /* some thread is in XProcessInternalConnection or XLockDisplay
	       so we have to see if we are it */
	    self = XThread_Self();
	if (!xthread_have_id(self)
	    || (!xthread_equal(self, dpy->lock->conni_thread)
		&& !xthread_equal(self, dpy->lock->locking_thread))) {
	    /* In the multi-threaded case, if there is someone else
	       reading events, then there aren't any available, so
	       we just return.  If we waited we would block.
	       */
	    if (dpy->lock && dpy->lock->event_awaiters)
		return dpy->qlen;
	    /* nobody here but us, so lock out any newcomers */
	    cvl = QueueEventReaderLock(dpy);
	}

	while (dpy->lock && cvl && dpy->lock->reply_first) {
	    /* note which events we have already seen so we'll know
	       if _XReply (in another thread) reads one */
	    entry_event_serial_num = dpy->next_event_serial_num;
	    ConditionWait(dpy, cvl->cv);
	    /* did _XReply read an event we can return? */
	    if (_XNewerQueuedEvent(dpy, entry_event_serial_num))
	    {
		UnlockNextEventReader(dpy);
		return 0;
	    }
	}
#endif /* XTHREADS*/

	if (_X11TransBytesReadable(dpy->trans_conn, &pend) < 0)
	    _XIOError(dpy);
#ifdef XCONN_CHECK_FREQ
	/* This is a crock, required because FIONREAD or equivalent is
	 * not guaranteed to detect a broken connection.
	 */
	if (!pend && !dpy->qlen && ++dpy->conn_checker >= XCONN_CHECK_FREQ)
	{
	    int	result;
#ifdef USE_POLL
	    struct pollfd filedes;
#else
	    fd_set r_mask;
	    static struct timeval zero_time;
#endif

	    dpy->conn_checker = 0;
#ifdef USE_POLL
	    filedes.fd = dpy->fd;
	    filedes.events = POLLIN;
	    if ((result = poll(&filedes, 1, 0)))
#else
	    FD_ZERO(&r_mask);
	    FD_SET(dpy->fd, &r_mask);
	    if ((result = Select(dpy->fd + 1, &r_mask, NULL, NULL, &zero_time)))
#endif
	    {
		if (result > 0)
		{
		    if (_X11TransBytesReadable(dpy->trans_conn, &pend) < 0)
			_XIOError(dpy);
		    /* we should not get zero, if we do, force a read */
		    if (!pend)
			pend = SIZEOF(xReply);
		}
		else if (result < 0 && !(ECHECK(EINTR) || ETEST()))
		    _XIOError(dpy);
	    }
	}
#endif /* XCONN_CHECK_FREQ */
	if (!(len = pend)) {
	    /* _XFlush can enqueue events */
#ifdef XTHREADS
	    if (cvl)
#endif
	    {
		UnlockNextEventReader(dpy);
	    }
	    return(dpy->qlen);
	}
      /* Force a read if there is not enough data.  Otherwise,
       * a select() loop at a higher-level will spin undesirably,
       * and we've seen at least one OS that appears to not update
       * the result from FIONREAD once it has returned nonzero.
       */
#ifdef XTHREADS
	if (dpy->lock && dpy->lock->reply_awaiters) {
	    read_buf = (char *)dpy->lock->reply_awaiters->buf;
	    len = SIZEOF(xReply);
	} else
#endif /* XTHREADS*/
	{
	    read_buf = buf.buf;

	    if (len < SIZEOF(xReply)
#ifdef XTHREADS
		|| dpy->async_handlers
#endif
		)
		len = SIZEOF(xReply);
	    else if (len > BUFSIZE)
		len = BUFSIZE;
	    len = (len / SIZEOF(xReply)) * SIZEOF(xReply);
	}
#ifdef XCONN_CHECK_FREQ
	dpy->conn_checker = 0;
#endif

	(void) _XRead (dpy, read_buf, (long) len);

#ifdef XTHREADS
	/* what did we actually read: reply or event? */
	if (dpy->lock && dpy->lock->reply_awaiters) {
	    if (((xReply *)read_buf)->generic.type == X_Reply ||
		((xReply *)read_buf)->generic.type == X_Error)
	    {
		dpy->lock->reply_was_read = True;
		dpy->lock->reply_first = True;
		if (read_buf != (char *)dpy->lock->reply_awaiters->buf)
		    memcpy(dpy->lock->reply_awaiters->buf, read_buf,
			   len);
		if (cvl) {
		    UnlockNextEventReader(dpy);
		}
		return(dpy->qlen); /* we read, so we can return */
	    } else if (read_buf != buf.buf)
		memcpy(buf.buf, read_buf, len);
	}
#endif /* XTHREADS*/

	STARTITERATE(rep,xReply,buf.buf,len > 0) {
	    if (rep->generic.type == X_Reply) {
                int tmp = len;
		RESETITERPTR(rep,xReply,
			     _XAsyncReply (dpy, rep,
					   ITERPTR(rep), &tmp, True));
                len = tmp;
		pend = len;
	    } else {
		if (rep->generic.type == X_Error)
		    _XError (dpy, (xError *)rep);
		else   /* must be an event packet */
		    _XEnq (dpy, (xEvent *)rep);
		INCITERPTR(rep,xReply);
		len -= SIZEOF(xReply);
	    }
	} ENDITERATE

#ifdef XTHREADS
	if (cvl)
#endif
	{
	    UnlockNextEventReader(dpy);
	}
	return(dpy->qlen);
}

/* _XReadEvents - Flush the output queue,
 * then read as many events as possible (but at least 1) and enqueue them
 */
void _XReadEvents(
	register Display *dpy)
{
	_XAlignedBuffer buf;
	BytesReadable_t pend;
	int len;
	register xReply *rep;
	Bool not_yet_flushed = True;
	char *read_buf;
	int i;
	int entry_event_serial_num = dpy->next_event_serial_num;
#ifdef XTHREADS
	struct _XCVList *cvl = NULL;
	xthread_t self;

#ifdef XTHREADS_DEBUG
	printf("_XReadEvents called in thread %x\n",
	       XThread_Self());
#endif
	/* create our condition variable and append to list,
	 * unless we were called from within XProcessInternalConnection
	 * or XLockDisplay
	 */
	xthread_clear_id(self);
	if (dpy->lock && (xthread_have_id (dpy->lock->conni_thread)
			  || xthread_have_id (dpy->lock->locking_thread)))
	    /* some thread is in XProcessInternalConnection or XLockDisplay
	       so we have to see if we are it */
	    self = XThread_Self();
	if (!xthread_have_id(self)
	    || (!xthread_equal(self, dpy->lock->conni_thread)
		&& !xthread_equal(self, dpy->lock->locking_thread)))
	    cvl = QueueEventReaderLock(dpy);
#endif /* XTHREADS */

	do {
#ifdef XTHREADS
	    /* if it is not our turn to read an event off the wire,
	       wait til we're at head of list */
	    if (dpy->lock && cvl &&
		(dpy->lock->event_awaiters != cvl ||
		 dpy->lock->reply_first)) {
		ConditionWait(dpy, cvl->cv);
		continue;
	    }
#endif /* XTHREADS */
	    /* find out how much data can be read */
	    if (_X11TransBytesReadable(dpy->trans_conn, &pend) < 0)
	    	_XIOError(dpy);
	    len = pend;

	    /* must read at least one xEvent; if none is pending, then
	       we'll just flush and block waiting for it */
	    if (len < SIZEOF(xEvent)
#ifdef XTHREADS
		|| dpy->async_handlers
#endif
		) {
	    	len = SIZEOF(xEvent);
		/* don't flush until the first time we would block */
		if (not_yet_flushed) {
		    _XFlush (dpy);
		    if (_XNewerQueuedEvent(dpy, entry_event_serial_num)) {
			/* _XReply has read an event for us */
			goto got_event;
		    }
		    not_yet_flushed = False;
		}
	    }

#ifdef XTHREADS
	    /* If someone is waiting for a reply, gamble that
	       the reply will be the next thing on the wire
	       and read it into their buffer. */
	    if (dpy->lock && dpy->lock->reply_awaiters) {
		read_buf = (char *)dpy->lock->reply_awaiters->buf;
		len = SIZEOF(xReply);
	    } else
#endif /* XTHREADS*/
	    {
		read_buf = buf.buf;

		/* but we won't read more than the max buffer size */
		if (len > BUFSIZE)
		    len = BUFSIZE;

		/* round down to an integral number of XReps */
		len = (len / SIZEOF(xEvent)) * SIZEOF(xEvent);
	    }

#ifdef XTHREADS
	    if (xthread_have_id(self))
		/* save value we may have to stick in conni_thread */
		dpy->lock->reading_thread = self;
#endif /* XTHREADS */
	    dpy->flags |= XlibDisplayReadEvents;
	    i = _XRead (dpy, read_buf, (long) len);
	    dpy->flags &= ~XlibDisplayReadEvents;
	    if (i == -2) {
		/* special flag from _XRead to say that internal connection has
		   done XPutBackEvent.  Which we can use so we're done. */
	      got_event:
#ifdef XTHREADS
		if (dpy->lock && dpy->lock->lock_wait) {
		    if (dpy->lock->event_awaiters != cvl)
			/* since it is not us, must be user lock thread */
			ConditionSignal(dpy,
					dpy->lock->event_awaiters->cv);
		    (*dpy->lock->lock_wait)(dpy);
		    continue;
		}
#endif
		break;
	    }
#ifdef XTHREADS
	    if (xthread_have_id(self))
		xthread_clear_id(dpy->lock->reading_thread);

	    /* what did we actually read: reply or event? */
	    if (dpy->lock && dpy->lock->reply_awaiters) {
		if (((xReply *)read_buf)->generic.type == X_Reply ||
		    ((xReply *)read_buf)->generic.type == X_Error)
		{
		    dpy->lock->reply_was_read = True;
		    dpy->lock->reply_first = True;
		    if (read_buf != (char *)dpy->lock->reply_awaiters->buf)
			memcpy(dpy->lock->reply_awaiters->buf,
			       read_buf, len);
		    ConditionSignal(dpy, dpy->lock->reply_awaiters->cv);
		    continue;
		} else if (read_buf != buf.buf)
		    memcpy(buf.buf, read_buf, len);
	    }
#endif /* XTHREADS */

	    STARTITERATE(rep,xReply,buf.buf,len > 0) {
		if (rep->generic.type == X_Reply) {
		    RESETITERPTR(rep,xReply,
				 _XAsyncReply (dpy, rep,
					       ITERPTR(rep), &len, True));
		    pend = len;
		} else {
		    if (rep->generic.type == X_Error)
			_XError (dpy, (xError *) rep);
		    else   /* must be an event packet */
                    {
                        if (rep->generic.type == GenericEvent)
                        {
                            int evlen;
                            evlen = (rep->generic.length << 2);
                            if (_XRead(dpy, &read_buf[len], evlen) == -2)
                                goto got_event; /* XXX: aargh! */
                        }

                        _XEnq (dpy, (xEvent *)rep);
                    }
		    INCITERPTR(rep,xReply);
		    len -= SIZEOF(xReply);
		}
	    } ENDITERATE;
	} while (!_XNewerQueuedEvent(dpy, entry_event_serial_num));

	UnlockNextEventReader(dpy);
}

/*
 * _XRead - Read bytes from the socket taking into account incomplete
 * reads.  This routine may have to be reworked if int < long.
 */
int _XRead(
	register Display *dpy,
	register char *data,
	register long size)
{
	register long bytes_read;
#ifdef XTHREADS
	int original_size = size;
#endif

	if ((dpy->flags & XlibDisplayIOError) || size == 0)
	    return 0;
	ESET(0);
	while ((bytes_read = _X11TransRead(dpy->trans_conn, data, (int)size))
		!= size) {

	    	if (bytes_read > 0) {
		    size -= bytes_read;
		    data += bytes_read;
		    }
		else if (ETEST()) {
		    if (_XWaitForReadable(dpy) == -2)
			return -2; /* internal connection did XPutBackEvent */
		    ESET(0);
		}
#ifdef SUNSYSV
		else if (ECHECK(0)) {
		    if (_XWaitForReadable(dpy) == -2)
			return -2; /* internal connection did XPutBackEvent */
		}
#endif
		else if (bytes_read == 0) {
		    /* Read failed because of end of file! */
		    ESET(EPIPE);
		    _XIOError(dpy);
		    }

		else  /* bytes_read is less than 0; presumably -1 */ {
		    /* If it's a system call interrupt, it's not an error. */
		    if (!ECHECK(EINTR))
		    	_XIOError(dpy);
		    }
	    	 }
#ifdef XTHREADS
       if (dpy->lock && dpy->lock->reply_bytes_left > 0)
       {
           dpy->lock->reply_bytes_left -= original_size;
           if (dpy->lock->reply_bytes_left == 0) {
	       dpy->flags &= ~XlibDisplayReply;
               UnlockNextReplyReader(dpy);
	   }
       }
#endif /* XTHREADS*/
	return 0;
}
#endif /* !USE_XCB */

#ifdef LONG64
void _XRead32(
    Display *dpy,
    register long *data,
    long len)
{
    register int *buf;
    register long i;

    if (len) {
	(void) _XRead(dpy, (char *)data, len);
	i = len >> 2;
	buf = (int *)data + i;
	data += i;
	while (--i >= 0)
	    *--data = *--buf;
    }
}
#endif /* LONG64 */

#ifdef WORD64

/*
 * XXX This is a *really* stupid way of doing this....
 * PACKBUFFERSIZE must be a multiple of 4.
 */

#define PACKBUFFERSIZE 4096


/*
 * _XRead32 - Read bytes from the socket unpacking each 32 bits
 *            into a long (64 bits on a CRAY computer).
 *
 */
static void _doXRead32(
        register Display *dpy,
        register long *data
        register long size,
	register char *packbuffer)
{
 long *lpack,*lp;
 long mask32 = 0x00000000ffffffff;
 long maskw, nwords, i, bits;

        _XReadPad (dpy, packbuffer, size);

        lp = data;
        lpack = (long *) packbuffer;
        nwords = size >> 2;
        bits = 32;

        for(i=0;i<nwords;i++){
            maskw = mask32 << bits;
           *lp++ = ( *lpack & maskw ) >> bits;
            bits = bits ^32;
            if(bits){
               lpack++;
            }
        }
}

void _XRead32(
    Display *dpy,
    long *data,
    long len)
{
    char packbuffer[PACKBUFFERSIZE];
    unsigned nunits = PACKBUFFERSIZE >> 2;

    for (; len > PACKBUFFERSIZE; len -= PACKBUFFERSIZE, data += nunits) {
	_doXRead32 (dpy, data, PACKBUFFERSIZE, packbuffer);
    }
    if (len) _doXRead32 (dpy, data, len, packbuffer);
}



/*
 * _XRead16 - Read bytes from the socket unpacking each 16 bits
 *            into a long (64 bits on a CRAY computer).
 *
 */
static _doXRead16(
        register Display *dpy,
        register short *data,
        register long size,
	char *packbuffer)
{
	long *lpack,*lp;
	long mask16 = 0x000000000000ffff;
	long maskw, nwords, i, bits;

        (void) _XRead(dpy,packbuffer,size);	/* don't do a padded read... */

        lp = (long *) data;
        lpack = (long *) packbuffer;
        nwords = size >> 1;  /* number of 16 bit words to be unpacked */
        bits = 48;
        for(i=0;i<nwords;i++){
            maskw = mask16 << bits;
           *lp++ = ( *lpack & maskw ) >> bits;
            bits -= 16;
            if(bits < 0){
               lpack++;
               bits = 48;
            }
        }
}

void _XRead16(
    Display *dpy,
    short *data,
    long len)
{
    char packbuffer[PACKBUFFERSIZE];
    unsigned nunits = PACKBUFFERSIZE >> 1;

    for (; len > PACKBUFFERSIZE; len -= PACKBUFFERSIZE, data += nunits) {
	_doXRead16 (dpy, data, PACKBUFFERSIZE, packbuffer);
    }
    if (len) _doXRead16 (dpy, data, len, packbuffer);
}

void _XRead16Pad(
    Display *dpy,
    short *data,
    long size)
{
    int slop = (size & 3);
    short slopbuf[3];

    _XRead16 (dpy, data, size);
    if (slop > 0) {
	_XRead16 (dpy, slopbuf, 4 - slop);
    }
}
#endif /* WORD64 */


#if !USE_XCB
/*
 * _XReadPad - Read bytes from the socket taking into account incomplete
 * reads.  If the number of bytes is not 0 mod 4, read additional pad
 * bytes. This routine may have to be reworked if int < long.
 */
void _XReadPad(
    	register Display *dpy,
	register char *data,
	register long size)
{
    	register long bytes_read;
	struct iovec iov[2];
	char pad[3];
#ifdef XTHREADS
        int original_size;
#endif

	if ((dpy->flags & XlibDisplayIOError) || size == 0) return;
	iov[0].iov_len = (int)size;
	iov[0].iov_base = data;
	/*
	 * The following hack is used to provide 32 bit long-word
	 * aligned padding.  The [1] vector is of length 0, 1, 2, or 3,
	 * whatever is needed.
	 */

	iov[1].iov_len = -size & 3;
	iov[1].iov_base = pad;
	size += iov[1].iov_len;
#ifdef XTHREADS
	original_size = size;
#endif
	ESET(0);
	while ((bytes_read = _X11TransReadv (dpy->trans_conn, iov, 2)) != size) {

	    if (bytes_read > 0) {
		size -= bytes_read;
		if (iov[0].iov_len < bytes_read) {
		    int pad_bytes_read = bytes_read - iov[0].iov_len;
		    iov[1].iov_len -= pad_bytes_read;
		    iov[1].iov_base =
			(char *)iov[1].iov_base + pad_bytes_read;
		    iov[0].iov_len = 0;
		    }
	    	else {
		    iov[0].iov_len -= bytes_read;
	    	    iov[0].iov_base = (char *)iov[0].iov_base + bytes_read;
	    	}
	    }
	    else if (ETEST()) {
		_XWaitForReadable(dpy);
		ESET(0);
	    }
#ifdef SUNSYSV
	    else if (ECHECK(0)) {
		_XWaitForReadable(dpy);
	    }
#endif
	    else if (bytes_read == 0) {
		/* Read failed because of end of file! */
		ESET(EPIPE);
		_XIOError(dpy);
		}

	    else  /* bytes_read is less than 0; presumably -1 */ {
		/* If it's a system call interrupt, it's not an error. */
		if (!ECHECK(EINTR))
		    _XIOError(dpy);
		}
	    }
#ifdef XTHREADS
       if (dpy->lock && dpy->lock->reply_bytes_left > 0)
       {
           dpy->lock->reply_bytes_left -= original_size;
           if (dpy->lock->reply_bytes_left == 0) {
	       dpy->flags &= ~XlibDisplayReply;
               UnlockNextReplyReader(dpy);
	   }
       }
#endif /* XTHREADS*/
}

/*
 * _XSend - Flush the buffer and send the client data. 32 bit word aligned
 * transmission is used, if size is not 0 mod 4, extra bytes are transmitted.
 * This routine may have to be reworked if int < long;
 */
void
_XSend (
	register Display *dpy,
	_Xconst char *data,
	register long size)
{
	struct iovec iov[3];
	static char const pad[3] = {0, 0, 0};
           /* XText8 and XText16 require that the padding bytes be zero! */

	long skip, dbufsize, padsize, total, todo;
	_XExtension *ext;

	if (!size || (dpy->flags & XlibDisplayIOError)) return;
	dbufsize = dpy->bufptr - dpy->buffer;
#ifdef XTHREADS
	dpy->flags |= XlibDisplayWriting;
	/* make sure no one else can put in data */
	dpy->bufptr = dpy->bufmax;
#endif
	padsize = -size & 3;
	for (ext = dpy->flushes; ext; ext = ext->next_flush) {
	    (*ext->before_flush)(dpy, &ext->codes, dpy->buffer, dbufsize);
	    (*ext->before_flush)(dpy, &ext->codes, (char *)data, size);
	    if (padsize)
		(*ext->before_flush)(dpy, &ext->codes, pad, padsize);
	}
	skip = 0;
	todo = total = dbufsize + size + padsize;

	/*
	 * There are 3 pieces that may need to be written out:
	 *
	 *     o  whatever is in the display buffer
	 *     o  the data passed in by the user
	 *     o  any padding needed to 32bit align the whole mess
	 *
	 * This loop looks at all 3 pieces each time through.  It uses skip
	 * to figure out whether or not a given piece is needed.
	 */
	while (total) {
	    long before = skip;		/* amount of whole thing written */
	    long remain = todo;		/* amount to try this time, <= total */
	    int i = 0;
	    long len;

	    /* You could be very general here and have "in" and "out" iovecs
	     * and write a loop without using a macro, but what the heck.  This
	     * translates to:
	     *
	     *     how much of this piece is new?
	     *     if more new then we are trying this time, clamp
	     *     if nothing new
	     *         then bump down amount already written, for next piece
	     *         else put new stuff in iovec, will need all of next piece
	     *
	     * Note that todo had better be at least 1 or else we'll end up
	     * writing 0 iovecs.
	     */
#define InsertIOV(pointer, length) \
	    len = (length) - before; \
	    if (len > remain) \
		len = remain; \
	    if (len <= 0) { \
		before = (-len); \
	    } else { \
		iov[i].iov_len = len; \
		iov[i].iov_base = (pointer) + before; \
		i++; \
		remain -= len; \
		before = 0; \
	    }

	    InsertIOV (dpy->buffer, dbufsize)
	    InsertIOV ((char *)data, size)
	    InsertIOV ((char *)pad, padsize)

	    ESET(0);
	    if ((len = _X11TransWritev(dpy->trans_conn, iov, i)) >= 0) {
		skip += len;
		total -= len;
		todo = total;
	    } else if (ETEST()) {
		_XWaitForWritable(dpy
#ifdef XTHREADS
				  , NULL
#endif
				  );
#ifdef SUNSYSV
	    } else if (ECHECK(0)) {
		_XWaitForWritable(dpy
#ifdef XTHREADS
				  , NULL
#endif
				  );
#endif
#ifdef ESZTEST
	    } else if (ESZTEST()) {
		if (todo > 1)
		  todo >>= 1;
		else {
		    _XWaitForWritable(dpy
#ifdef XTHREADS
				      , NULL
#endif
				      );
		}
#endif
	    } else if (!ECHECK(EINTR)) {
		_XIOError(dpy);
	    }
	}
	dpy->last_req = (char *) & _dummy_request;
	_XSetSeqSyncFunction(dpy);
	dpy->bufptr = dpy->buffer;
#ifdef XTHREADS
	dpy->flags &= ~XlibDisplayWriting;
#endif
	return;
}

static void
_XGetMiscCode(
    register Display *dpy)
{
    xQueryExtensionReply qrep;
    register xQueryExtensionReq *qreq;
    xXCMiscGetVersionReply vrep;
    register xXCMiscGetVersionReq *vreq;

    if (dpy->xcmisc_opcode)
	return;
    GetReq(QueryExtension, qreq);
    qreq->nbytes = sizeof(XCMiscExtensionName) - 1;
    qreq->length += (qreq->nbytes+(unsigned)3)>>2;
    _XSend(dpy, XCMiscExtensionName, (long)qreq->nbytes);
    if (!_XReply (dpy, (xReply *)&qrep, 0, xTrue))
	dpy->xcmisc_opcode = -1;
    else {
	GetReq(XCMiscGetVersion, vreq);
	vreq->reqType = qrep.major_opcode;
	vreq->miscReqType = X_XCMiscGetVersion;
	vreq->majorVersion = XCMiscMajorVersion;
	vreq->minorVersion = XCMiscMinorVersion;
	if (!_XReply (dpy, (xReply *)&vrep, 0, xTrue))
	    dpy->xcmisc_opcode = -1;
	else
	    dpy->xcmisc_opcode = qrep.major_opcode;
    }
}

void
_XIDHandler(
    register Display *dpy)
{
    xXCMiscGetXIDRangeReply grep;
    register xXCMiscGetXIDRangeReq *greq;

    if (dpy->resource_max == dpy->resource_mask + 1) {
	_XGetMiscCode(dpy);
	if (dpy->xcmisc_opcode > 0) {
	    GetReq(XCMiscGetXIDRange, greq);
	    greq->reqType = dpy->xcmisc_opcode;
	    greq->miscReqType = X_XCMiscGetXIDRange;
	    if (_XReply (dpy, (xReply *)&grep, 0, xTrue) && grep.count) {
		dpy->resource_id = ((grep.start_id - dpy->resource_base) >>
				    dpy->resource_shift);
		dpy->resource_max = dpy->resource_id;
		if (grep.count > 5)
		    dpy->resource_max += grep.count - 6;
		dpy->resource_max <<= dpy->resource_shift;
	    }
	    sync_while_locked(dpy);
	}
    }
}

/*
 * _XAllocID - resource ID allocation routine.
 */
XID _XAllocID(
    register Display *dpy)
{
   XID id;

   id = dpy->resource_id << dpy->resource_shift;
   if (id >= dpy->resource_max) {
	_XSetPrivSyncFunction(dpy);
       dpy->resource_max = dpy->resource_mask + 1;
   }
   if (id <= dpy->resource_mask) {
       dpy->resource_id++;
       return (dpy->resource_base + id);
   }
   if (id != 0x10000000) {
       (void) fprintf(stderr,
		      "Xlib: resource ID allocation space exhausted!\n");
       id = 0x10000000;
       dpy->resource_id = id >> dpy->resource_shift;
   }
   return id;
}

/*
 * _XAllocIDs - multiple resource ID allocation routine.
 */
void _XAllocIDs(
    register Display *dpy,
    XID *ids,
    int count)
{
    XID id;
    int i;
    xXCMiscGetXIDListReply grep;
    register xXCMiscGetXIDListReq *greq;

    id = dpy->resource_id << dpy->resource_shift;
    if (dpy->resource_max <= dpy->resource_mask &&
	id <= dpy->resource_mask &&
	(dpy->resource_max - id) > ((count - 1) << dpy->resource_shift)) {
	id += dpy->resource_base;
	for (i = 0; i < count; i++) {
	    ids[i] = id;
	    id += (1 << dpy->resource_shift);
	    dpy->resource_id++;
	}
	return;
    }
    grep.count = 0;
    _XGetMiscCode(dpy);
    if (dpy->xcmisc_opcode > 0) {
	GetReq(XCMiscGetXIDList, greq);
	greq->reqType = dpy->xcmisc_opcode;
	greq->miscReqType = X_XCMiscGetXIDList;
	greq->count = count;
	if (_XReply(dpy, (xReply *)&grep, 0, xFalse) && grep.count) {
	    _XRead32(dpy, (long *) ids, 4L * (long) (grep.count));
	    for (i = 0; i < grep.count; i++) {
		id = (ids[i] - dpy->resource_base) >> dpy->resource_shift;
		if (id >= dpy->resource_id)
		    dpy->resource_id = id;
	    }
	    if (id >= dpy->resource_max) {
		_XSetPrivSyncFunction(dpy);
		dpy->resource_max = dpy->resource_mask + 1;
	    }
	}
    }
    for (i = grep.count; i < count; i++)
	ids[i] = XAllocID(dpy);
}
#endif /* !USE_XCB */

/*
 * The hard part about this is that we only get 16 bits from a reply.
 * We have three values that will march along, with the following invariant:
 *	dpy->last_request_read <= rep->sequenceNumber <= dpy->request
 * We have to keep
 *	dpy->request - dpy->last_request_read < 2^16
 * or else we won't know for sure what value to use in events.  We do this
 * by forcing syncs when we get close.
 */

unsigned long
_XSetLastRequestRead(
    register Display *dpy,
    register xGenericReply *rep)
{
    register unsigned long	newseq, lastseq;

    lastseq = dpy->last_request_read;
    /*
     * KeymapNotify has no sequence number, but is always guaranteed
     * to immediately follow another event, except when generated via
     * SendEvent (hmmm).
     */
    if ((rep->type & 0x7f) == KeymapNotify)
	return(lastseq);

    newseq = (lastseq & ~((unsigned long)0xffff)) | rep->sequenceNumber;

    if (newseq < lastseq) {
	newseq += 0x10000;
	if (newseq > dpy->request) {
	    (void) fprintf (stderr,
	    "Xlib: sequence lost (0x%lx > 0x%lx) in reply type 0x%x!\n",
			    newseq, dpy->request,
			    (unsigned int) rep->type);
	    newseq -= 0x10000;
	}
    }

    dpy->last_request_read = newseq;
    return(newseq);
}

#if !USE_XCB
/*
 * _XReply - Wait for a reply packet and copy its contents into the
 * specified rep.  Meanwhile we must handle error and event packets that
 * we may encounter.
 */
Status
_XReply (
    register Display *dpy,
    register xReply *rep,
    int extra,		/* number of 32-bit words expected after the reply */
    Bool discard)	/* should I discard data following "extra" words? */
{
    /* Pull out the serial number now, so that (currently illegal) requests
     * generated by an error handler don't confuse us.
     */
    unsigned long cur_request = dpy->request;
#ifdef XTHREADS
    struct _XCVList *cvl;
#endif

    if (dpy->flags & XlibDisplayIOError)
	return 0;

#ifdef XTHREADS
    /* create our condition variable and append to list */
    cvl = QueueReplyReaderLock(dpy);
    if (cvl) {
	cvl->buf = rep;
	if (dpy->lock->reply_awaiters == cvl && !dpy->lock->event_awaiters)
	    dpy->lock->reply_first = True;
    }

#ifdef XTHREADS_DEBUG
    printf("_XReply called in thread %x, adding %x to cvl\n",
	   XThread_Self(), cvl);
#endif

    _XFlushInt(dpy, cvl ? cvl->cv : NULL);
    /* if it is not our turn to read a reply off the wire,
     * wait til we're at head of list.  if there is an event waiter,
     * and our reply hasn't been read, they'll be in select and will
     * hand control back to us next.
     */
    if(dpy->lock &&
       (dpy->lock->reply_awaiters != cvl || !dpy->lock->reply_first)) {
	ConditionWait(dpy, cvl->cv);
    }
    dpy->flags |= XlibDisplayReply;
#else /* XTHREADS else */
    _XFlush(dpy);
#endif

    for (;;) {
#ifdef XTHREADS
	/* Did another thread's _XReadEvents get our reply by accident? */
	if (!dpy->lock || !dpy->lock->reply_was_read)
#endif
	    (void) _XRead(dpy, (char *)rep, (long)SIZEOF(xReply));
#ifdef XTHREADS
	if (dpy->lock)
	    dpy->lock->reply_was_read = False;
#endif

	switch ((int)rep->generic.type) {

	    case X_Reply:
	        /* Reply received.  Fast update for synchronous replies,
		 * but deal with multiple outstanding replies.
		 */
	        if (rep->generic.sequenceNumber == (cur_request & 0xffff))
		    dpy->last_request_read = cur_request;
		else {
		    int pend = SIZEOF(xReply);
		    if (_XAsyncReply(dpy, rep, (char *)rep, &pend, False)
			!= (char *)rep)
			continue;
		}
		if (extra <= rep->generic.length) {
		    if (extra > 0)
			/*
			 * Read the extra data into storage immediately
			 * following the GenericReply structure.
			 */
			(void) _XRead (dpy, (char *) (NEXTPTR(rep,xReply)),
				((long)extra) << 2);
		    if (discard) {
			if (extra < rep->generic.length)
			    _XEatData(dpy, (rep->generic.length - extra) << 2);
		    }
#ifdef XTHREADS
		    if (dpy->lock) {
			if (discard) {
			    dpy->lock->reply_bytes_left = 0;
			} else {
			    dpy->lock->reply_bytes_left =
				(rep->generic.length - extra) << 2;
			}
			if (dpy->lock->reply_bytes_left == 0) {
			    dpy->flags &= ~XlibDisplayReply;
			    UnlockNextReplyReader(dpy);
			}
		    } else
			dpy->flags &= ~XlibDisplayReply;
#endif
		    return 1;
		}
		/*
		 *if we get here, then extra > rep->generic.length--meaning we
		 * read a reply that's shorter than we expected.  This is an
		 * error,  but we still need to figure out how to handle it...
		 */
		(void) _XRead (dpy, (char *) (NEXTPTR(rep,xReply)),
			((long) rep->generic.length) << 2);
		dpy->flags &= ~XlibDisplayReply;
		UnlockNextReplyReader(dpy);
		_XIOError (dpy);
		return (0);

    	    case X_Error:
	    	{
	        register _XExtension *ext;
		register Bool ret = False;
		int ret_code;
		xError *err = (xError *) rep;
		unsigned long serial;

		dpy->flags &= ~XlibDisplayReply;
		serial = _XSetLastRequestRead(dpy, (xGenericReply *)rep);
		if (serial == cur_request)
			/* do not die on "no such font", "can't allocate",
			   "can't grab" failures */
			switch ((int)err->errorCode) {
			case BadName:
			    switch (err->majorCode) {
				case X_LookupColor:
				case X_AllocNamedColor:
				    UnlockNextReplyReader(dpy);
				    return(0);
			    }
			    break;
			case BadFont:
			    if (err->majorCode == X_QueryFont) {
				UnlockNextReplyReader(dpy);
				return (0);
			    }
			    break;
			case BadAlloc:
			case BadAccess:
			    UnlockNextReplyReader(dpy);
			    return (0);
			}
		/*
		 * we better see if there is an extension who may
		 * want to suppress the error.
		 */
		for (ext = dpy->ext_procs; !ret && ext; ext = ext->next) {
		    if (ext->error)
		       ret = (*ext->error)(dpy, err, &ext->codes, &ret_code);
		}
		if (!ret) {
		    _XError(dpy, err);
		    ret_code = 0;
		}
		if (serial == cur_request) {
		    UnlockNextReplyReader(dpy);
		    return(ret_code);
		}

		} /* case X_Error */
		break;
	    default:
		_XEnq(dpy, (xEvent *) rep);
#ifdef XTHREADS
		if (dpy->lock && dpy->lock->event_awaiters)
		    ConditionSignal(dpy, dpy->lock->event_awaiters->cv);
#endif
		break;
	    }
	}
}

static char *
_XAsyncReply(
    Display *dpy,
    register xReply *rep,
    char *buf,
    register int *lenp,
    Bool discard)
{
    register _XAsyncHandler *async, *next;
    register int len;
    register Bool consumed = False;
    char *nbuf;

    (void) _XSetLastRequestRead(dpy, &rep->generic);
    len = SIZEOF(xReply) + (rep->generic.length << 2);
    if (len < SIZEOF(xReply)) {
	_XIOError (dpy);
	buf += *lenp;
	*lenp = 0;
	return buf;
    }

    for (async = dpy->async_handlers; async; async = next) {
	next = async->next;
	if ((consumed = (*async->handler)(dpy, rep, buf, *lenp, async->data)))
	    break;
    }
    if (!consumed) {
	if (!discard)
	    return buf;
	(void) fprintf(stderr,
		       "Xlib: unexpected async reply (sequence 0x%lx)!\n",
		       dpy->last_request_read);
#ifdef XTHREADS
#ifdef XTHREADS_DEBUG
	printf("thread %x, unexpected async reply\n", XThread_Self());
#endif
#endif
	if (len > *lenp)
	    _XEatData(dpy, len - *lenp);
    }
    if (len < SIZEOF(xReply))
    {
	_XIOError (dpy);
	buf += *lenp;
	*lenp = 0;
	return buf;
    }
    if (len >= *lenp) {
	buf += *lenp;
	*lenp = 0;
	return buf;
    }
    *lenp -= len;
    buf += len;
    len = *lenp;
    nbuf = buf;
    while (len > SIZEOF(xReply)) {
	if (*buf == X_Reply)
	    return nbuf;
	buf += SIZEOF(xReply);
	len -= SIZEOF(xReply);
    }
    if (len > 0 && len < SIZEOF(xReply)) {
	buf = nbuf;
	len = SIZEOF(xReply) - len;
	nbuf -= len;
	memmove(nbuf, buf, *lenp);
	(void) _XRead(dpy, nbuf + *lenp, (long)len);
	*lenp += len;
    }
    return nbuf;
}
#endif /* !USE_XCB */

/*
 * Support for internal connections, such as an IM might use.
 * By Stephen Gildea, X Consortium, September 1993
 */

/* _XRegisterInternalConnection
 * Each IM (or Xlib extension) that opens a file descriptor that Xlib should
 * include in its select/poll mask must call this function to register the
 * fd with Xlib.  Any XConnectionWatchProc registered by XAddConnectionWatch
 * will also be called.
 *
 * Whenever Xlib detects input available on fd, it will call callback
 * with call_data to process it.  If non-Xlib code calls select/poll
 * and detects input available, it must call XProcessInternalConnection,
 * which will call the associated callback.
 *
 * Non-Xlib code can learn about these additional fds by calling
 * XInternalConnectionNumbers or, more typically, by registering
 * a XConnectionWatchProc with XAddConnectionWatch
 * to be called when fds are registered or unregistered.
 *
 * Returns True if registration succeeded, False if not, typically
 * because could not allocate memory.
 * Assumes Display locked when called.
 */
Status
_XRegisterInternalConnection(
    Display* dpy,
    int fd,
    _XInternalConnectionProc callback,
    XPointer call_data
)
{
    struct _XConnectionInfo *new_conni, **iptr;
    struct _XConnWatchInfo *watchers;
    XPointer *wd;

    new_conni = (struct _XConnectionInfo*)Xmalloc(sizeof(struct _XConnectionInfo));
    if (!new_conni)
	return 0;
    new_conni->watch_data = (XPointer *)Xmalloc(dpy->watcher_count * sizeof(XPointer));
    if (!new_conni->watch_data) {
	Xfree(new_conni);
	return 0;
    }
    new_conni->fd = fd;
    new_conni->read_callback = callback;
    new_conni->call_data = call_data;
    new_conni->next = NULL;
    /* link new structure onto end of list */
    for (iptr = &dpy->im_fd_info; *iptr; iptr = &(*iptr)->next)
	;
    *iptr = new_conni;
    dpy->im_fd_length++;
    _XPollfdCacheAdd(dpy, fd);

    for (watchers=dpy->conn_watchers, wd=new_conni->watch_data;
	 watchers;
	 watchers=watchers->next, wd++) {
	*wd = NULL;		/* for cleanliness */
	(*watchers->fn) (dpy, watchers->client_data, fd, True, wd);
    }

    return 1;
}

/* _XUnregisterInternalConnection
 * Each IM (or Xlib extension) that closes a file descriptor previously
 * registered with _XRegisterInternalConnection must call this function.
 * Any XConnectionWatchProc registered by XAddConnectionWatch
 * will also be called.
 *
 * Assumes Display locked when called.
 */
void
_XUnregisterInternalConnection(
    Display* dpy,
    int fd
)
{
    struct _XConnectionInfo *info_list, **prev;
    struct _XConnWatchInfo *watch;
    XPointer *wd;

    for (prev = &dpy->im_fd_info; (info_list = *prev);
	 prev = &info_list->next) {
	if (info_list->fd == fd) {
	    *prev = info_list->next;
	    dpy->im_fd_length--;
	    for (watch=dpy->conn_watchers, wd=info_list->watch_data;
		 watch;
		 watch=watch->next, wd++) {
		(*watch->fn) (dpy, watch->client_data, fd, False, wd);
	    }
	    if (info_list->watch_data)
		Xfree (info_list->watch_data);
	    Xfree (info_list);
	    break;
	}
    }
    _XPollfdCacheDel(dpy, fd);
}

/* XInternalConnectionNumbers
 * Returns an array of fds and an array of corresponding call data.
 * Typically a XConnectionWatchProc registered with XAddConnectionWatch
 * will be used instead of this function to discover
 * additional fds to include in the select/poll mask.
 *
 * The list is allocated with Xmalloc and should be freed by the caller
 * with Xfree;
 */
Status
XInternalConnectionNumbers(
    Display *dpy,
    int **fd_return,
    int *count_return
)
{
    int count;
    struct _XConnectionInfo *info_list;
    int *fd_list;

    LockDisplay(dpy);
    count = 0;
    for (info_list=dpy->im_fd_info; info_list; info_list=info_list->next)
	count++;
    fd_list = (int*) Xmalloc (count * sizeof(int));
    if (!fd_list) {
	UnlockDisplay(dpy);
	return 0;
    }
    count = 0;
    for (info_list=dpy->im_fd_info; info_list; info_list=info_list->next) {
	fd_list[count] = info_list->fd;
	count++;
    }
    UnlockDisplay(dpy);

    *fd_return = fd_list;
    *count_return = count;
    return 1;
}

void _XProcessInternalConnection(
    Display *dpy,
    struct _XConnectionInfo *conn_info)
{
    dpy->flags |= XlibDisplayProcConni;
#if defined(XTHREADS) && !USE_XCB
    if (dpy->lock) {
	/* check cache to avoid call to thread_self */
	if (xthread_have_id(dpy->lock->reading_thread))
	    dpy->lock->conni_thread = dpy->lock->reading_thread;
	else
	    dpy->lock->conni_thread = XThread_Self();
    }
#endif /* XTHREADS && !USE_XCB */
    UnlockDisplay(dpy);
    (*conn_info->read_callback) (dpy, conn_info->fd, conn_info->call_data);
    LockDisplay(dpy);
#if defined(XTHREADS) && !USE_XCB
    if (dpy->lock)
	xthread_clear_id(dpy->lock->conni_thread);
#endif /* XTHREADS && !USE_XCB */
    dpy->flags &= ~XlibDisplayProcConni;
}

/* XProcessInternalConnection
 * Call the _XInternalConnectionProc registered by _XRegisterInternalConnection
 * for this fd.
 * The Display is NOT locked during the call.
 */
void
XProcessInternalConnection(
    Display* dpy,
    int fd
)
{
    struct _XConnectionInfo *info_list;

    LockDisplay(dpy);
    for (info_list=dpy->im_fd_info; info_list; info_list=info_list->next) {
	if (info_list->fd == fd) {
	    _XProcessInternalConnection(dpy, info_list);
	    break;
	}
    }
    UnlockDisplay(dpy);
}

/* XAddConnectionWatch
 * Register a callback to be called whenever _XRegisterInternalConnection
 * or _XUnregisterInternalConnection is called.
 * Callbacks are called with the Display locked.
 * If any connections are already registered, the callback is immediately
 * called for each of them.
 */
Status
XAddConnectionWatch(
    Display* dpy,
    XConnectionWatchProc callback,
    XPointer client_data
)
{
    struct _XConnWatchInfo *new_watcher, **wptr;
    struct _XConnectionInfo *info_list;
    XPointer *wd_array;

    LockDisplay(dpy);

    /* allocate new watch data */
    for (info_list=dpy->im_fd_info; info_list; info_list=info_list->next) {
	wd_array = (XPointer *)Xrealloc((char *)info_list->watch_data,
					(dpy->watcher_count + 1) *
					sizeof(XPointer));
	if (!wd_array) {
	    UnlockDisplay(dpy);
	    return 0;
	}
	wd_array[dpy->watcher_count] = NULL;	/* for cleanliness */
    }

    new_watcher = (struct _XConnWatchInfo*)Xmalloc(sizeof(struct _XConnWatchInfo));
    if (!new_watcher) {
	UnlockDisplay(dpy);
	return 0;
    }
    new_watcher->fn = callback;
    new_watcher->client_data = client_data;
    new_watcher->next = NULL;

    /* link new structure onto end of list */
    for (wptr = &dpy->conn_watchers; *wptr; wptr = &(*wptr)->next)
	;
    *wptr = new_watcher;
    dpy->watcher_count++;

    /* call new watcher on all currently registered fds */
    for (info_list=dpy->im_fd_info; info_list; info_list=info_list->next) {
	(*callback) (dpy, client_data, info_list->fd, True,
		     info_list->watch_data + dpy->watcher_count - 1);
    }

    UnlockDisplay(dpy);
    return 1;
}

/* XRemoveConnectionWatch
 * Unregister a callback registered by XAddConnectionWatch.
 * Both callback and client_data must match what was passed to
 * XAddConnectionWatch.
 */
void
XRemoveConnectionWatch(
    Display* dpy,
    XConnectionWatchProc callback,
    XPointer client_data
)
{
    struct _XConnWatchInfo *watch;
    struct _XConnWatchInfo *previous = NULL;
    struct _XConnectionInfo *conni;
    int counter = 0;

    LockDisplay(dpy);
    for (watch=dpy->conn_watchers; watch; watch=watch->next) {
	if (watch->fn == callback  &&  watch->client_data == client_data) {
	    if (previous)
		previous->next = watch->next;
	    else
		dpy->conn_watchers = watch->next;
	    Xfree (watch);
	    dpy->watcher_count--;
	    /* remove our watch_data for each connection */
	    for (conni=dpy->im_fd_info; conni; conni=conni->next) {
		/* don't bother realloc'ing; these arrays are small anyway */
		/* overlapping */
		memmove(conni->watch_data+counter,
			conni->watch_data+counter+1,
			dpy->watcher_count - counter);
	    }
	    break;
	}
	previous = watch;
	counter++;
    }
    UnlockDisplay(dpy);
}

/* end of internal connections support */


#if !USE_XCB
/* Read and discard "n" 8-bit bytes of data */

void _XEatData(
    Display *dpy,
    register unsigned long n)
{
#define SCRATCHSIZE 2048
    char buf[SCRATCHSIZE];

    while (n > 0) {
	register long bytes_read = (n > SCRATCHSIZE) ? SCRATCHSIZE : n;
	(void) _XRead (dpy, buf, bytes_read);
	n -= bytes_read;
    }
#undef SCRATCHSIZE
}
#endif /* !USE_XCB */

/* Cookie jar implementation
   dpy->cookiejar is a linked list. _XEnq receives the events but leaves
   them in the normal EQ. _XStoreEvent returns the cookie event (minus
   data pointer) and adds it to the cookiejar. _XDeq just removes
   the entry like any other event but resets the data pointer for
   cookie events (to avoid double-free, the memory is re-used by Xlib).

   _XFetchEventCookie (called from XGetEventData) removes a cookie from the
   jar. _XFreeEventCookies removes all unclaimed cookies from the jar
   (called by XNextEvent).

   _XFreeDisplayStructure calls _XFreeEventCookies for each cookie in the
   normal EQ.
 */

#include "utlist.h"
struct stored_event {
    XGenericEventCookie ev;
    struct stored_event *prev;
    struct stored_event *next;
};

Bool
_XIsEventCookie(Display *dpy, XEvent *ev)
{
    return (ev->xcookie.type == GenericEvent &&
	    dpy->generic_event_vec[ev->xcookie.extension & 0x7F] != NULL);
}

/**
 * Free all events in the event list.
 */
void
_XFreeEventCookies(Display *dpy)
{
    struct stored_event **head, *e, *tmp;

    if (!dpy->cookiejar)
        return;

    head = (struct stored_event**)&dpy->cookiejar;

    DL_FOREACH_SAFE(*head, e, tmp) {
        XFree(e->ev.data);
        XFree(e);
        if (dpy->cookiejar == e)
            dpy->cookiejar = NULL;
    }
}

/**
 * Add an event to the display's event list. This event must be freed on the
 * next call to XNextEvent().
 */
void
_XStoreEventCookie(Display *dpy, XEvent *event)
{
    XGenericEventCookie* cookie = &event->xcookie;
    struct stored_event **head, *add;

    if (!_XIsEventCookie(dpy, event))
        return;

    head = (struct stored_event**)(&dpy->cookiejar);

    add = Xmalloc(sizeof(struct stored_event));
    if (!add) {
        ESET(ENOMEM);
        _XIOError(dpy);
    }
    add->ev = *cookie;
    DL_APPEND(*head, add);
    cookie->data = NULL; /* don't return data yet, must be claimed */
}

/**
 * Return the event with the given cookie and remove it from the list.
 */
Bool
_XFetchEventCookie(Display *dpy, XGenericEventCookie* ev)
{
    Bool ret = False;
    struct stored_event **head, *event;
    head = (struct stored_event**)&dpy->cookiejar;

    if (!_XIsEventCookie(dpy, (XEvent*)ev))
        return ret;

    DL_FOREACH(*head, event) {
        if (event->ev.cookie == ev->cookie &&
            event->ev.extension == ev->extension &&
            event->ev.evtype == ev->evtype) {
            *ev = event->ev;
            DL_DELETE(*head, event);
            Xfree(event);
            ret = True;
            break;
        }
    }

    return ret;
}

Bool
_XCopyEventCookie(Display *dpy, XGenericEventCookie *in, XGenericEventCookie *out)
{
    Bool ret = False;
    int extension;

    if (!_XIsEventCookie(dpy, (XEvent*)in) || !out)
        return ret;

    extension = in->extension & 0x7F;

    if (!dpy->generic_event_copy_vec[extension])
        return ret;

    ret = ((*dpy->generic_event_copy_vec[extension])(dpy, in, out));
    out->cookie = ret ? ++dpy->next_cookie  : 0;
    return ret;
}


/*
 * _XEnq - Place event packets on the display's queue.
 * note that no squishing of move events in V11, since there
 * is pointer motion hints....
 */
void _XEnq(
	register Display *dpy,
	register xEvent *event)
{
	register _XQEvent *qelt;
	int type, extension;

	if ((qelt = dpy->qfree)) {
		/* If dpy->qfree is non-NULL do this, else malloc a new one. */
		dpy->qfree = qelt->next;
	}
	else if ((qelt =
	    (_XQEvent *) Xmalloc((unsigned)sizeof(_XQEvent))) == NULL) {
		/* Malloc call failed! */
		ESET(ENOMEM);
		_XIOError(dpy);
	}
	qelt->next = NULL;

	type = event->u.u.type & 0177;
	extension = ((xGenericEvent*)event)->extension;
	/* If an extension has registerd a generic_event_vec handler, then
	 * it can handle event cookies. Otherwise, proceed with the normal
	 * event handlers.
	 *
	 * If the generic_event_vec is called, qelt->event is a event cookie
	 * with the data pointer and the "free" pointer set. Data pointer is
	 * some memory allocated by the extension.
	 */
        if (type == GenericEvent && dpy->generic_event_vec[extension & 0x7F]) {
	    XGenericEventCookie *cookie = &qelt->event.xcookie;
	    (*dpy->generic_event_vec[extension & 0x7F])(dpy, cookie, event);
	    cookie->cookie = ++dpy->next_cookie;

	    qelt->qserial_num = dpy->next_event_serial_num++;
	    if (dpy->tail)	dpy->tail->next = qelt;
	    else		dpy->head = qelt;

	    dpy->tail = qelt;
	    dpy->qlen++;
	} else if ((*dpy->event_vec[type])(dpy, &qelt->event, event)) {
	    qelt->qserial_num = dpy->next_event_serial_num++;
	    if (dpy->tail)	dpy->tail->next = qelt;
	    else 		dpy->head = qelt;

	    dpy->tail = qelt;
	    dpy->qlen++;
	} else {
	    /* ignored, or stashed away for many-to-one compression */
	    qelt->next = dpy->qfree;
	    dpy->qfree = qelt;
	}
}

/*
 * _XDeq - Remove event packet from the display's queue.
 */
void _XDeq(
    register Display *dpy,
    register _XQEvent *prev,	/* element before qelt */
    register _XQEvent *qelt)	/* element to be unlinked */
{
    if (prev) {
	if ((prev->next = qelt->next) == NULL)
	    dpy->tail = prev;
    } else {
	/* no prev, so removing first elt */
	if ((dpy->head = qelt->next) == NULL)
	    dpy->tail = NULL;
    }
    qelt->qserial_num = 0;
    qelt->next = dpy->qfree;
    dpy->qfree = qelt;
    dpy->qlen--;

    if (_XIsEventCookie(dpy, &qelt->event)) {
	XGenericEventCookie* cookie = &qelt->event.xcookie;
	/* dpy->qfree is re-used, reset memory to avoid double free on
	 * _XFreeDisplayStructure */
	cookie->data = NULL;
    }
}

/*
 * EventToWire in separate file in that often not needed.
 */

/*ARGSUSED*/
Bool
_XUnknownWireEvent(
    register Display *dpy,	/* pointer to display structure */
    register XEvent *re,	/* pointer to where event should be reformatted */
    register xEvent *event)	/* wire protocol event */
{
#ifdef notdef
	(void) fprintf(stderr,
	    "Xlib: unhandled wire event! event number = %d, display = %x\n.",
			event->u.u.type, dpy);
#endif
	return(False);
}

Bool
_XUnknownWireEventCookie(
    Display *dpy,	/* pointer to display structure */
    XGenericEventCookie *re,	/* pointer to where event should be reformatted */
    xEvent *event)	/* wire protocol event */
{
#ifdef notdef
	fprintf(stderr,
	    "Xlib: unhandled wire cookie event! extension number = %d, display = %x\n.",
			((xGenericEvent*)event)->extension, dpy);
#endif
	return(False);
}

Bool
_XUnknownCopyEventCookie(
    Display *dpy,	/* pointer to display structure */
    XGenericEventCookie *in,	/* source */
    XGenericEventCookie *out)	/* destination */
{
#ifdef notdef
	fprintf(stderr,
	    "Xlib: unhandled cookie event copy! extension number = %d, display = %x\n.",
			in->extension, dpy);
#endif
	return(False);
}

/*ARGSUSED*/
Status
_XUnknownNativeEvent(
    register Display *dpy,	/* pointer to display structure */
    register XEvent *re,	/* pointer to where event should be reformatted */
    register xEvent *event)	/* wire protocol event */
{
#ifdef notdef
	(void) fprintf(stderr,
 	   "Xlib: unhandled native event! event number = %d, display = %x\n.",
			re->type, dpy);
#endif
	return(0);
}
/*
 * reformat a wire event into an XEvent structure of the right type.
 */
Bool
_XWireToEvent(
    register Display *dpy,	/* pointer to display structure */
    register XEvent *re,	/* pointer to where event should be reformatted */
    register xEvent *event)	/* wire protocol event */
{

	re->type = event->u.u.type & 0x7f;
	((XAnyEvent *)re)->serial = _XSetLastRequestRead(dpy,
					(xGenericReply *)event);
	((XAnyEvent *)re)->send_event = ((event->u.u.type & 0x80) != 0);
	((XAnyEvent *)re)->display = dpy;

	/* Ignore the leading bit of the event type since it is set when a
		client sends an event rather than the server. */

	switch (event-> u.u.type & 0177) {
	      case KeyPress:
	      case KeyRelease:
	        {
			register XKeyEvent *ev = (XKeyEvent*) re;
			ev->root 	= event->u.keyButtonPointer.root;
			ev->window 	= event->u.keyButtonPointer.event;
			ev->subwindow 	= event->u.keyButtonPointer.child;
			ev->time 	= event->u.keyButtonPointer.time;
			ev->x 		= cvtINT16toInt(event->u.keyButtonPointer.eventX);
			ev->y 		= cvtINT16toInt(event->u.keyButtonPointer.eventY);
			ev->x_root 	= cvtINT16toInt(event->u.keyButtonPointer.rootX);
			ev->y_root 	= cvtINT16toInt(event->u.keyButtonPointer.rootY);
			ev->state	= event->u.keyButtonPointer.state;
			ev->same_screen	= event->u.keyButtonPointer.sameScreen;
			ev->keycode 	= event->u.u.detail;
		}
	      	break;
	      case ButtonPress:
	      case ButtonRelease:
	        {
			register XButtonEvent *ev =  (XButtonEvent *) re;
			ev->root 	= event->u.keyButtonPointer.root;
			ev->window 	= event->u.keyButtonPointer.event;
			ev->subwindow 	= event->u.keyButtonPointer.child;
			ev->time 	= event->u.keyButtonPointer.time;
			ev->x 		= cvtINT16toInt(event->u.keyButtonPointer.eventX);
			ev->y 		= cvtINT16toInt(event->u.keyButtonPointer.eventY);
			ev->x_root 	= cvtINT16toInt(event->u.keyButtonPointer.rootX);
			ev->y_root 	= cvtINT16toInt(event->u.keyButtonPointer.rootY);
			ev->state	= event->u.keyButtonPointer.state;
			ev->same_screen	= event->u.keyButtonPointer.sameScreen;
			ev->button 	= event->u.u.detail;
		}
	        break;
	      case MotionNotify:
	        {
			register XMotionEvent *ev =   (XMotionEvent *)re;
			ev->root 	= event->u.keyButtonPointer.root;
			ev->window 	= event->u.keyButtonPointer.event;
			ev->subwindow 	= event->u.keyButtonPointer.child;
			ev->time 	= event->u.keyButtonPointer.time;
			ev->x 		= cvtINT16toInt(event->u.keyButtonPointer.eventX);
			ev->y 		= cvtINT16toInt(event->u.keyButtonPointer.eventY);
			ev->x_root 	= cvtINT16toInt(event->u.keyButtonPointer.rootX);
			ev->y_root 	= cvtINT16toInt(event->u.keyButtonPointer.rootY);
			ev->state	= event->u.keyButtonPointer.state;
			ev->same_screen	= event->u.keyButtonPointer.sameScreen;
			ev->is_hint 	= event->u.u.detail;
		}
	        break;
	      case EnterNotify:
	      case LeaveNotify:
		{
			register XCrossingEvent *ev   = (XCrossingEvent *) re;
			ev->root	= event->u.enterLeave.root;
			ev->window	= event->u.enterLeave.event;
			ev->subwindow	= event->u.enterLeave.child;
			ev->time	= event->u.enterLeave.time;
			ev->x		= cvtINT16toInt(event->u.enterLeave.eventX);
			ev->y		= cvtINT16toInt(event->u.enterLeave.eventY);
			ev->x_root	= cvtINT16toInt(event->u.enterLeave.rootX);
			ev->y_root	= cvtINT16toInt(event->u.enterLeave.rootY);
			ev->state	= event->u.enterLeave.state;
			ev->mode	= event->u.enterLeave.mode;
			ev->same_screen = (event->u.enterLeave.flags &
				ELFlagSameScreen) && True;
			ev->focus	= (event->u.enterLeave.flags &
			  	ELFlagFocus) && True;
			ev->detail	= event->u.u.detail;
		}
		  break;
	      case FocusIn:
	      case FocusOut:
		{
			register XFocusChangeEvent *ev = (XFocusChangeEvent *) re;
			ev->window 	= event->u.focus.window;
			ev->mode	= event->u.focus.mode;
			ev->detail	= event->u.u.detail;
		}
		  break;
	      case KeymapNotify:
		{
			register XKeymapEvent *ev = (XKeymapEvent *) re;
			ev->window	= None;
			memcpy(&ev->key_vector[1],
			       (char *)((xKeymapEvent *) event)->map,
			       sizeof (((xKeymapEvent *) event)->map));
		}
		break;
	      case Expose:
		{
			register XExposeEvent *ev = (XExposeEvent *) re;
			ev->window	= event->u.expose.window;
			ev->x		= event->u.expose.x;
			ev->y		= event->u.expose.y;
			ev->width	= event->u.expose.width;
			ev->height	= event->u.expose.height;
			ev->count	= event->u.expose.count;
		}
		break;
	      case GraphicsExpose:
		{
		    register XGraphicsExposeEvent *ev =
			(XGraphicsExposeEvent *) re;
		    ev->drawable	= event->u.graphicsExposure.drawable;
		    ev->x		= event->u.graphicsExposure.x;
		    ev->y		= event->u.graphicsExposure.y;
		    ev->width		= event->u.graphicsExposure.width;
		    ev->height		= event->u.graphicsExposure.height;
		    ev->count		= event->u.graphicsExposure.count;
		    ev->major_code	= event->u.graphicsExposure.majorEvent;
		    ev->minor_code	= event->u.graphicsExposure.minorEvent;
		}
		break;
	      case NoExpose:
		{
		    register XNoExposeEvent *ev = (XNoExposeEvent *) re;
		    ev->drawable	= event->u.noExposure.drawable;
		    ev->major_code	= event->u.noExposure.majorEvent;
		    ev->minor_code	= event->u.noExposure.minorEvent;
		}
		break;
	      case VisibilityNotify:
		{
		    register XVisibilityEvent *ev = (XVisibilityEvent *) re;
		    ev->window		= event->u.visibility.window;
		    ev->state		= event->u.visibility.state;
		}
		break;
	      case CreateNotify:
		{
		    register XCreateWindowEvent *ev =
			 (XCreateWindowEvent *) re;
		    ev->window		= event->u.createNotify.window;
		    ev->parent		= event->u.createNotify.parent;
		    ev->x		= cvtINT16toInt(event->u.createNotify.x);
		    ev->y		= cvtINT16toInt(event->u.createNotify.y);
		    ev->width		= event->u.createNotify.width;
		    ev->height		= event->u.createNotify.height;
		    ev->border_width	= event->u.createNotify.borderWidth;
		    ev->override_redirect	= event->u.createNotify.override;
		}
		break;
	      case DestroyNotify:
		{
		    register XDestroyWindowEvent *ev =
				(XDestroyWindowEvent *) re;
		    ev->window		= event->u.destroyNotify.window;
		    ev->event		= event->u.destroyNotify.event;
		}
		break;
	      case UnmapNotify:
		{
		    register XUnmapEvent *ev = (XUnmapEvent *) re;
		    ev->window		= event->u.unmapNotify.window;
		    ev->event		= event->u.unmapNotify.event;
		    ev->from_configure	= event->u.unmapNotify.fromConfigure;
		}
		break;
	      case MapNotify:
		{
		    register XMapEvent *ev = (XMapEvent *) re;
		    ev->window		= event->u.mapNotify.window;
		    ev->event		= event->u.mapNotify.event;
		    ev->override_redirect	= event->u.mapNotify.override;
		}
		break;
	      case MapRequest:
		{
		    register XMapRequestEvent *ev = (XMapRequestEvent *) re;
		    ev->window		= event->u.mapRequest.window;
		    ev->parent		= event->u.mapRequest.parent;
		}
		break;
	      case ReparentNotify:
		{
		    register XReparentEvent *ev = (XReparentEvent *) re;
		    ev->event		= event->u.reparent.event;
		    ev->window		= event->u.reparent.window;
		    ev->parent		= event->u.reparent.parent;
		    ev->x		= cvtINT16toInt(event->u.reparent.x);
		    ev->y		= cvtINT16toInt(event->u.reparent.y);
		    ev->override_redirect	= event->u.reparent.override;
		}
		break;
	      case ConfigureNotify:
		{
		    register XConfigureEvent *ev = (XConfigureEvent *) re;
		    ev->event	= event->u.configureNotify.event;
		    ev->window	= event->u.configureNotify.window;
		    ev->above	= event->u.configureNotify.aboveSibling;
		    ev->x	= cvtINT16toInt(event->u.configureNotify.x);
		    ev->y	= cvtINT16toInt(event->u.configureNotify.y);
		    ev->width	= event->u.configureNotify.width;
		    ev->height	= event->u.configureNotify.height;
		    ev->border_width  = event->u.configureNotify.borderWidth;
		    ev->override_redirect = event->u.configureNotify.override;
		}
		break;
	      case ConfigureRequest:
		{
		    register XConfigureRequestEvent *ev =
		        (XConfigureRequestEvent *) re;
		    ev->window		= event->u.configureRequest.window;
		    ev->parent		= event->u.configureRequest.parent;
		    ev->above		= event->u.configureRequest.sibling;
		    ev->x		= cvtINT16toInt(event->u.configureRequest.x);
		    ev->y		= cvtINT16toInt(event->u.configureRequest.y);
		    ev->width		= event->u.configureRequest.width;
		    ev->height		= event->u.configureRequest.height;
		    ev->border_width	= event->u.configureRequest.borderWidth;
		    ev->value_mask	= event->u.configureRequest.valueMask;
		    ev->detail  	= event->u.u.detail;
		}
		break;
	      case GravityNotify:
		{
		    register XGravityEvent *ev = (XGravityEvent *) re;
		    ev->window		= event->u.gravity.window;
		    ev->event		= event->u.gravity.event;
		    ev->x		= cvtINT16toInt(event->u.gravity.x);
		    ev->y		= cvtINT16toInt(event->u.gravity.y);
		}
		break;
	      case ResizeRequest:
		{
		    register XResizeRequestEvent *ev =
			(XResizeRequestEvent *) re;
		    ev->window		= event->u.resizeRequest.window;
		    ev->width		= event->u.resizeRequest.width;
		    ev->height		= event->u.resizeRequest.height;
		}
		break;
	      case CirculateNotify:
		{
		    register XCirculateEvent *ev = (XCirculateEvent *) re;
		    ev->window		= event->u.circulate.window;
		    ev->event		= event->u.circulate.event;
		    ev->place		= event->u.circulate.place;
		}
		break;
	      case CirculateRequest:
		{
		    register XCirculateRequestEvent *ev =
		        (XCirculateRequestEvent *) re;
		    ev->window		= event->u.circulate.window;
		    ev->parent		= event->u.circulate.event;
		    ev->place		= event->u.circulate.place;
		}
		break;
	      case PropertyNotify:
		{
		    register XPropertyEvent *ev = (XPropertyEvent *) re;
		    ev->window		= event->u.property.window;
		    ev->atom		= event->u.property.atom;
		    ev->time		= event->u.property.time;
		    ev->state		= event->u.property.state;
		}
		break;
	      case SelectionClear:
		{
		    register XSelectionClearEvent *ev =
			 (XSelectionClearEvent *) re;
		    ev->window		= event->u.selectionClear.window;
		    ev->selection	= event->u.selectionClear.atom;
		    ev->time		= event->u.selectionClear.time;
		}
		break;
	      case SelectionRequest:
		{
		    register XSelectionRequestEvent *ev =
		        (XSelectionRequestEvent *) re;
		    ev->owner		= event->u.selectionRequest.owner;
		    ev->requestor	= event->u.selectionRequest.requestor;
		    ev->selection	= event->u.selectionRequest.selection;
		    ev->target		= event->u.selectionRequest.target;
		    ev->property	= event->u.selectionRequest.property;
		    ev->time		= event->u.selectionRequest.time;
		}
		break;
	      case SelectionNotify:
		{
		    register XSelectionEvent *ev = (XSelectionEvent *) re;
		    ev->requestor	= event->u.selectionNotify.requestor;
		    ev->selection	= event->u.selectionNotify.selection;
		    ev->target		= event->u.selectionNotify.target;
		    ev->property	= event->u.selectionNotify.property;
		    ev->time		= event->u.selectionNotify.time;
		}
		break;
	      case ColormapNotify:
		{
		    register XColormapEvent *ev = (XColormapEvent *) re;
		    ev->window		= event->u.colormap.window;
		    ev->colormap	= event->u.colormap.colormap;
		    ev->new		= event->u.colormap.new;
		    ev->state		= event->u.colormap.state;
	        }
		break;
	      case ClientMessage:
		{
		   register int i;
		   register XClientMessageEvent *ev
		   			= (XClientMessageEvent *) re;
		   ev->window		= event->u.clientMessage.window;
		   ev->format		= event->u.u.detail;
		   switch (ev->format) {
			case 8:
			   ev->message_type = event->u.clientMessage.u.b.type;
			   for (i = 0; i < 20; i++)
			     ev->data.b[i] = event->u.clientMessage.u.b.bytes[i];
			   break;
			case 16:
			   ev->message_type = event->u.clientMessage.u.s.type;
			   ev->data.s[0] = cvtINT16toShort(event->u.clientMessage.u.s.shorts0);
			   ev->data.s[1] = cvtINT16toShort(event->u.clientMessage.u.s.shorts1);
			   ev->data.s[2] = cvtINT16toShort(event->u.clientMessage.u.s.shorts2);
			   ev->data.s[3] = cvtINT16toShort(event->u.clientMessage.u.s.shorts3);
			   ev->data.s[4] = cvtINT16toShort(event->u.clientMessage.u.s.shorts4);
			   ev->data.s[5] = cvtINT16toShort(event->u.clientMessage.u.s.shorts5);
			   ev->data.s[6] = cvtINT16toShort(event->u.clientMessage.u.s.shorts6);
			   ev->data.s[7] = cvtINT16toShort(event->u.clientMessage.u.s.shorts7);
			   ev->data.s[8] = cvtINT16toShort(event->u.clientMessage.u.s.shorts8);
			   ev->data.s[9] = cvtINT16toShort(event->u.clientMessage.u.s.shorts9);
			   break;
			case 32:
			   ev->message_type = event->u.clientMessage.u.l.type;
			   ev->data.l[0] = cvtINT32toLong(event->u.clientMessage.u.l.longs0);
			   ev->data.l[1] = cvtINT32toLong(event->u.clientMessage.u.l.longs1);
			   ev->data.l[2] = cvtINT32toLong(event->u.clientMessage.u.l.longs2);
			   ev->data.l[3] = cvtINT32toLong(event->u.clientMessage.u.l.longs3);
			   ev->data.l[4] = cvtINT32toLong(event->u.clientMessage.u.l.longs4);
			   break;
			default: /* XXX should never occur */
				break;
		    }
	        }
		break;
	      case MappingNotify:
		{
		   register XMappingEvent *ev = (XMappingEvent *)re;
		   ev->window		= 0;
		   ev->first_keycode 	= event->u.mappingNotify.firstKeyCode;
		   ev->request 		= event->u.mappingNotify.request;
		   ev->count 		= event->u.mappingNotify.count;
		}
		break;
	      default:
		return(_XUnknownWireEvent(dpy, re, event));
	}
	return(True);
}


/*
 * _XDefaultIOError - Default fatal system error reporting routine.  Called
 * when an X internal system error is encountered.
 */
int _XDefaultIOError(
	Display *dpy)
{
	if (ECHECK(EPIPE)) {
	    (void) fprintf (stderr,
	"X connection to %s broken (explicit kill or server shutdown).\r\n",
			    DisplayString (dpy));
	} else {
	    (void) fprintf (stderr,
			"XIO:  fatal IO error %d (%s) on X server \"%s\"\r\n",
#ifdef WIN32
			WSAGetLastError(), strerror(WSAGetLastError()),
#else
			errno, strerror (errno),
#endif
			DisplayString (dpy));
	    (void) fprintf (stderr,
	 "      after %lu requests (%lu known processed) with %d events remaining.\r\n",
			NextRequest(dpy) - 1, LastKnownRequestProcessed(dpy),
			QLength(dpy));

	}
	exit(1);
        return(0); /* dummy - function should never return */
}


static int _XPrintDefaultError(
    Display *dpy,
    XErrorEvent *event,
    FILE *fp)
{
    char buffer[BUFSIZ];
    char mesg[BUFSIZ];
    char number[32];
    const char *mtype = "XlibMessage";
    register _XExtension *ext = (_XExtension *)NULL;
    _XExtension *bext = (_XExtension *)NULL;
    XGetErrorText(dpy, event->error_code, buffer, BUFSIZ);
    XGetErrorDatabaseText(dpy, mtype, "XError", "X Error", mesg, BUFSIZ);
    (void) fprintf(fp, "%s:  %s\n  ", mesg, buffer);
    XGetErrorDatabaseText(dpy, mtype, "MajorCode", "Request Major code %d",
	mesg, BUFSIZ);
    (void) fprintf(fp, mesg, event->request_code);
    if (event->request_code < 128) {
	sprintf(number, "%d", event->request_code);
	XGetErrorDatabaseText(dpy, "XRequest", number, "", buffer, BUFSIZ);
    } else {
	for (ext = dpy->ext_procs;
	     ext && (ext->codes.major_opcode != event->request_code);
	     ext = ext->next)
	  ;
	if (ext)
	    strcpy(buffer, ext->name);
	else
	    buffer[0] = '\0';
    }
    (void) fprintf(fp, " (%s)\n", buffer);
    if (event->request_code >= 128) {
	XGetErrorDatabaseText(dpy, mtype, "MinorCode", "Request Minor code %d",
			      mesg, BUFSIZ);
	fputs("  ", fp);
	(void) fprintf(fp, mesg, event->minor_code);
	if (ext) {
	    sprintf(mesg, "%s.%d", ext->name, event->minor_code);
	    XGetErrorDatabaseText(dpy, "XRequest", mesg, "", buffer, BUFSIZ);
	    (void) fprintf(fp, " (%s)", buffer);
	}
	fputs("\n", fp);
    }
    if (event->error_code >= 128) {
	/* kludge, try to find the extension that caused it */
	buffer[0] = '\0';
	for (ext = dpy->ext_procs; ext; ext = ext->next) {
	    if (ext->error_string)
		(*ext->error_string)(dpy, event->error_code, &ext->codes,
				     buffer, BUFSIZ);
	    if (buffer[0]) {
		bext = ext;
		break;
	    }
	    if (ext->codes.first_error &&
		ext->codes.first_error < (int)event->error_code &&
		(!bext || ext->codes.first_error > bext->codes.first_error))
		bext = ext;
	}
	if (bext)
	    sprintf(buffer, "%s.%d", bext->name,
		    event->error_code - bext->codes.first_error);
	else
	    strcpy(buffer, "Value");
	XGetErrorDatabaseText(dpy, mtype, buffer, "", mesg, BUFSIZ);
	if (mesg[0]) {
	    fputs("  ", fp);
	    (void) fprintf(fp, mesg, event->resourceid);
	    fputs("\n", fp);
	}
	/* let extensions try to print the values */
	for (ext = dpy->ext_procs; ext; ext = ext->next) {
	    if (ext->error_values)
		(*ext->error_values)(dpy, event, fp);
	}
    } else if ((event->error_code == BadWindow) ||
	       (event->error_code == BadPixmap) ||
	       (event->error_code == BadCursor) ||
	       (event->error_code == BadFont) ||
	       (event->error_code == BadDrawable) ||
	       (event->error_code == BadColor) ||
	       (event->error_code == BadGC) ||
	       (event->error_code == BadIDChoice) ||
	       (event->error_code == BadValue) ||
	       (event->error_code == BadAtom)) {
	if (event->error_code == BadValue)
	    XGetErrorDatabaseText(dpy, mtype, "Value", "Value 0x%x",
				  mesg, BUFSIZ);
	else if (event->error_code == BadAtom)
	    XGetErrorDatabaseText(dpy, mtype, "AtomID", "AtomID 0x%x",
				  mesg, BUFSIZ);
	else
	    XGetErrorDatabaseText(dpy, mtype, "ResourceID", "ResourceID 0x%x",
				  mesg, BUFSIZ);
	fputs("  ", fp);
	(void) fprintf(fp, mesg, event->resourceid);
	fputs("\n", fp);
    }
    XGetErrorDatabaseText(dpy, mtype, "ErrorSerial", "Error Serial #%d",
			  mesg, BUFSIZ);
    fputs("  ", fp);
    (void) fprintf(fp, mesg, event->serial);
    XGetErrorDatabaseText(dpy, mtype, "CurrentSerial", "Current Serial #%d",
			  mesg, BUFSIZ);
    fputs("\n  ", fp);
    (void) fprintf(fp, mesg, dpy->request);
    fputs("\n", fp);
    if (event->error_code == BadImplementation) return 0;
    return 1;
}

int _XDefaultError(
	Display *dpy,
	XErrorEvent *event)
{
    if (_XPrintDefaultError (dpy, event, stderr) == 0) return 0;
    exit(1);
    /*NOTREACHED*/
}

/*ARGSUSED*/
Bool _XDefaultWireError(Display *display, XErrorEvent *he, xError *we)
{
    return True;
}

/*
 * _XError - upcall internal or user protocol error handler
 */
int _XError (
    Display *dpy,
    register xError *rep)
{
    /*
     * X_Error packet encountered!  We need to unpack the error before
     * giving it to the user.
     */
    XEvent event; /* make it a large event */
    register _XAsyncHandler *async, *next;

    event.xerror.serial = _XSetLastRequestRead(dpy, (xGenericReply *)rep);

    for (async = dpy->async_handlers; async; async = next) {
	next = async->next;
	if ((*async->handler)(dpy, (xReply *)rep,
			      (char *)rep, SIZEOF(xError), async->data))
	    return 0;
    }

    event.xerror.display = dpy;
    event.xerror.type = X_Error;
    event.xerror.resourceid = rep->resourceID;
    event.xerror.error_code = rep->errorCode;
    event.xerror.request_code = rep->majorCode;
    event.xerror.minor_code = rep->minorCode;
    if (dpy->error_vec &&
	!(*dpy->error_vec[rep->errorCode])(dpy, &event.xerror, rep))
	return 0;
    if (_XErrorFunction != NULL) {
	int rtn_val;
#if defined(XTHREADS) && !USE_XCB
	if (dpy->lock)
	    (*dpy->lock->user_lock_display)(dpy);
	UnlockDisplay(dpy);
#endif /* XTHREADS && !USE_XCB */
	rtn_val = (*_XErrorFunction)(dpy, (XErrorEvent *)&event); /* upcall */
#if defined(XTHREADS) && !USE_XCB
	LockDisplay(dpy);
	if (dpy->lock)
	    (*dpy->lock->user_unlock_display)(dpy);
#endif /* XTHREADS && !USE_XCB */
	return rtn_val;
    } else {
	return _XDefaultError(dpy, (XErrorEvent *)&event);
    }
}

/*
 * _XIOError - call user connection error handler and exit
 */
int
_XIOError (
    Display *dpy)
{
    dpy->flags |= XlibDisplayIOError;
#ifdef WIN32
    errno = WSAGetLastError();
#endif

    /* This assumes that the thread calling exit will call any atexit handlers.
     * If this does not hold, then an alternate solution would involve
     * registering an atexit handler to take over the lock, which would only
     * assume that the same thread calls all the atexit handlers. */
#ifdef XTHREADS
    if (dpy->lock)
	(*dpy->lock->user_lock_display)(dpy);
#endif
    UnlockDisplay(dpy);

    if (_XIOErrorFunction != NULL)
	(*_XIOErrorFunction)(dpy);
    else
	_XDefaultIOError(dpy);
    exit (1);
    return 0;
}


/*
 * This routine can be used to (cheaply) get some memory within a single
 * Xlib routine for scratch space.  A single buffer is reused each time
 * if possible.  To be MT safe, you can only call this between a call to
 * GetReq* and a call to Data* or _XSend*, or in a context when the thread
 * is guaranteed to not unlock the display.
 */
char *_XAllocScratch(
	register Display *dpy,
	unsigned long nbytes)
{
	if (nbytes > dpy->scratch_length) {
	    if (dpy->scratch_buffer) Xfree (dpy->scratch_buffer);
	    if ((dpy->scratch_buffer = Xmalloc((unsigned) nbytes)))
		dpy->scratch_length = nbytes;
	    else dpy->scratch_length = 0;
	}
	return (dpy->scratch_buffer);
}

/*
 * Scratch space allocator you can call any time, multiple times, and be
 * MT safe, but you must hand the buffer back with _XFreeTemp.
 */
char *_XAllocTemp(
    register Display *dpy,
    unsigned long nbytes)
{
    char *buf;

    buf = _XAllocScratch(dpy, nbytes);
    dpy->scratch_buffer = NULL;
    dpy->scratch_length = 0;
    return buf;
}

void _XFreeTemp(
    register Display *dpy,
    char *buf,
    unsigned long nbytes)
{
    if (dpy->scratch_buffer)
	Xfree(dpy->scratch_buffer);
    dpy->scratch_buffer = buf;
    dpy->scratch_length = nbytes;
}

/*
 * Given a visual id, find the visual structure for this id on this display.
 */
Visual *_XVIDtoVisual(
	Display *dpy,
	VisualID id)
{
	register int i, j, k;
	register Screen *sp;
	register Depth *dp;
	register Visual *vp;
	for (i = 0; i < dpy->nscreens; i++) {
		sp = &dpy->screens[i];
		for (j = 0; j < sp->ndepths; j++) {
			dp = &sp->depths[j];
			/* if nvisuals == 0 then visuals will be NULL */
			for (k = 0; k < dp->nvisuals; k++) {
				vp = &dp->visuals[k];
				if (vp->visualid == id) return (vp);
			}
		}
	}
	return (NULL);
}

int
XFree (void *data)
{
	Xfree (data);
	return 1;
}

#ifdef _XNEEDBCOPYFUNC
void _Xbcopy(b1, b2, length)
    register char *b1, *b2;
    register length;
{
    if (b1 < b2) {
	b2 += length;
	b1 += length;
	while (length--)
	    *--b2 = *--b1;
    } else {
	while (length--)
	    *b2++ = *b1++;
    }
}
#endif

#ifdef DataRoutineIsProcedure
void Data(
	Display *dpy,
	char *data,
	long len)
{
	if (dpy->bufptr + (len) <= dpy->bufmax) {
		memcpy(dpy->bufptr, data, (int)len);
		dpy->bufptr += ((len) + 3) & ~3;
	} else {
		_XSend(dpy, data, len);
	}
}
#endif /* DataRoutineIsProcedure */


#ifdef LONG64
int
_XData32(
    Display *dpy,
    register long *data,
    unsigned len)
{
    register int *buf;
    register long i;

    while (len) {
	buf = (int *)dpy->bufptr;
	i = dpy->bufmax - (char *)buf;
	if (!i) {
	    _XFlush(dpy);
	    continue;
	}
	if (len < i)
	    i = len;
	dpy->bufptr = (char *)buf + i;
	len -= i;
	i >>= 2;
	while (--i >= 0)
	    *buf++ = *data++;
    }
    return 0;
}
#endif /* LONG64 */

#ifdef WORD64

/*
 * XXX This is a *really* stupid way of doing this.  It should just use
 * dpy->bufptr directly, taking into account where in the word it is.
 */

/*
 * Data16 - Place 16 bit data in the buffer.
 *
 * "dpy" is a pointer to a Display.
 * "data" is a pointer to the data.
 * "len" is the length in bytes of the data.
 */

static doData16(
    register Display *dpy,
    short *data,
    unsigned len,
    char *packbuffer)
{
    long *lp,*lpack;
    long i, nwords,bits;
    long mask16 = 0x000000000000ffff;

        lp = (long *)data;
        lpack = (long *)packbuffer;

/*  nwords is the number of 16 bit values to be packed,
 *  the low order 16 bits of each word will be packed
 *  into 64 bit words
 */
        nwords = len >> 1;
        bits = 48;

        for(i=0;i<nwords;i++){
	   if (bits == 48) *lpack = 0;
           *lpack ^= (*lp & mask16) << bits;
           bits -= 16 ;
           lp++;
           if(bits < 0){
               lpack++;
               bits = 48;
           }
        }
        Data(dpy, packbuffer, len);
}

_XData16 (
    Display *dpy,
    short *data,
    unsigned len)
{
    char packbuffer[PACKBUFFERSIZE];
    unsigned nunits = PACKBUFFERSIZE >> 1;

    for (; len > PACKBUFFERSIZE; len -= PACKBUFFERSIZE, data += nunits) {
	doData16 (dpy, data, PACKBUFFERSIZE, packbuffer);
    }
    if (len) doData16 (dpy, data, len, packbuffer);
}

/*
 * Data32 - Place 32 bit data in the buffer.
 *
 * "dpy" is a pointer to a Display.
 * "data" is a pointer to the data.
 * "len" is the length in bytes of the data.
 */

static doData32(
    register Display *dpy
    long *data,
    unsigned len,
    char *packbuffer)
{
    long *lp,*lpack;
    long i,bits,nwords;
    long mask32 = 0x00000000ffffffff;

        lpack = (long *) packbuffer;
        lp = data;

/*  nwords is the number of 32 bit values to be packed
 *  the low order 32 bits of each word will be packed
 *  into 64 bit words
 */
        nwords = len >> 2;
        bits = 32;

        for(i=0;i<nwords;i++){
	   if (bits == 32) *lpack = 0;
           *lpack ^= (*lp & mask32) << bits;
           bits = bits ^32;
           lp++;
           if(bits)
              lpack++;
        }
        Data(dpy, packbuffer, len);
}

void _XData32(
    Display *dpy,
    long *data,
    unsigned len)
{
    char packbuffer[PACKBUFFERSIZE];
    unsigned nunits = PACKBUFFERSIZE >> 2;

    for (; len > PACKBUFFERSIZE; len -= PACKBUFFERSIZE, data += nunits) {
	doData32 (dpy, data, PACKBUFFERSIZE, packbuffer);
    }
    if (len) doData32 (dpy, data, len, packbuffer);
}

#endif /* WORD64 */


/* Make sure this produces the same string as DefineLocal/DefineSelf in xdm.
 * Otherwise, Xau will not be able to find your cookies in the Xauthority file.
 *
 * Note: POSIX says that the ``nodename'' member of utsname does _not_ have
 *       to have sufficient information for interfacing to the network,
 *       and so, you may be better off using gethostname (if it exists).
 */

#if (defined(_POSIX_SOURCE) && !defined(AIXV3) && !defined(__QNX__)) || defined(hpux) || defined(SVR4)
#define NEED_UTSNAME
#include <sys/utsname.h>
#else
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#endif

/*
 * _XGetHostname - similar to gethostname but allows special processing.
 */
int _XGetHostname (
    char *buf,
    int maxlen)
{
    int len;

#ifdef NEED_UTSNAME
    struct utsname name;

    if (maxlen <= 0 || buf == NULL)
	return 0;

    uname (&name);
    len = strlen (name.nodename);
    if (len >= maxlen) len = maxlen - 1;
    strncpy (buf, name.nodename, len);
    buf[len] = '\0';
#else
    if (maxlen <= 0 || buf == NULL)
	return 0;

    buf[0] = '\0';
    (void) gethostname (buf, maxlen);
    buf [maxlen - 1] = '\0';
    len = strlen(buf);
#endif /* NEED_UTSNAME */
    return len;
}


/*
 * _XScreenOfWindow - get the Screen of a given window
 */

Screen *_XScreenOfWindow(Display *dpy, Window w)
{
    register int i;
    Window root;
    int x, y;				/* dummy variables */
    unsigned int width, height, bw, depth;  /* dummy variables */

    if (XGetGeometry (dpy, w, &root, &x, &y, &width, &height,
		      &bw, &depth) == False) {
	return NULL;
    }
    for (i = 0; i < ScreenCount (dpy); i++) {	/* find root from list */
	if (root == RootWindow (dpy, i)) {
	    return ScreenOfDisplay (dpy, i);
	}
    }
    return NULL;
}


#if defined(WIN32)

/*
 * These functions are intended to be used internally to Xlib only.
 * These functions will always prefix the path with a DOS drive in the
 * form "<drive-letter>:". As such, these functions are only suitable
 * for use by Xlib function that supply a root-based path to some
 * particular file, e.g. <ProjectRoot>/lib/X11/locale/locale.dir will
 * be converted to "C:/usr/X11R6.3/lib/X11/locale/locale.dir".
 */

static int access_file (path, pathbuf, len_pathbuf, pathret)
    char* path;
    char* pathbuf;
    int len_pathbuf;
    char** pathret;
{
    if (access (path, F_OK) == 0) {
	if (strlen (path) < len_pathbuf)
	    *pathret = pathbuf;
	else
	    *pathret = Xmalloc (strlen (path) + 1);
	if (*pathret) {
	    strcpy (*pathret, path);
	    return 1;
	}
    }
    return 0;
}

static int AccessFile (path, pathbuf, len_pathbuf, pathret)
    char* path;
    char* pathbuf;
    int len_pathbuf;
    char** pathret;
{
    unsigned long drives;
    int i, len;
    char* drive;
    char buf[MAX_PATH];
    char* bufp;

    /* just try the "raw" name first and see if it works */
    if (access_file (path, pathbuf, len_pathbuf, pathret))
	return 1;

    /* try the places set in the environment */
    drive = getenv ("_XBASEDRIVE");
#ifdef __UNIXOS2__
    if (!drive)
	drive = getenv ("X11ROOT");
#endif
    if (!drive)
	drive = "C:";
    len = strlen (drive) + strlen (path);
    if (len < MAX_PATH) bufp = buf;
    else bufp = Xmalloc (len + 1);
    strcpy (bufp, drive);
    strcat (bufp, path);
    if (access_file (bufp, pathbuf, len_pathbuf, pathret)) {
	if (bufp != buf) Xfree (bufp);
	return 1;
    }

#ifndef __UNIXOS2__
    /* one last place to look */
    drive = getenv ("HOMEDRIVE");
    if (drive) {
	len = strlen (drive) + strlen (path);
	if (len < MAX_PATH) bufp = buf;
	else bufp = Xmalloc (len + 1);
	strcpy (bufp, drive);
	strcat (bufp, path);
	if (access_file (bufp, pathbuf, len_pathbuf, pathret)) {
	    if (bufp != buf) Xfree (bufp);
	    return 1;
	}
    }

    /* tried everywhere else, go fishing */
#define C_DRIVE ('C' - 'A')
#define Z_DRIVE ('Z' - 'A')
    /* does OS/2 (with or with gcc-emx) have getdrives? */
    drives = _getdrives ();
    for (i = C_DRIVE; i <= Z_DRIVE; i++) { /* don't check on A: or B: */
	if ((1 << i) & drives) {
	    len = 2 + strlen (path);
	    if (len < MAX_PATH) bufp = buf;
	    else bufp = Xmalloc (len + 1);
	    *bufp = 'A' + i;
	    *(bufp + 1) = ':';
	    *(bufp + 2) = '\0';
	    strcat (bufp, path);
	    if (access_file (bufp, pathbuf, len_pathbuf, pathret)) {
		if (bufp != buf) Xfree (bufp);
		return 1;
	    }
	}
    }
#endif
    return 0;
}

int _XOpenFile(path, flags)
    _Xconst char* path;
    int flags;
{
    char buf[MAX_PATH];
    char* bufp = NULL;
    int ret = -1;
    UINT olderror = SetErrorMode (SEM_FAILCRITICALERRORS);

    if (AccessFile (path, buf, MAX_PATH, &bufp))
	ret = open (bufp, flags);

    (void) SetErrorMode (olderror);

    if (bufp != buf) Xfree (bufp);

    return ret;
}

int _XOpenFileMode(path, flags, mode)
    _Xconst char* path;
    int flags;
    mode_t mode;
{
    char buf[MAX_PATH];
    char* bufp = NULL;
    int ret = -1;
    UINT olderror = SetErrorMode (SEM_FAILCRITICALERRORS);

    if (AccessFile (path, buf, MAX_PATH, &bufp))
	ret = open (bufp, flags, mode);

    (void) SetErrorMode (olderror);

    if (bufp != buf) Xfree (bufp);

    return ret;
}

void* _XFopenFile(path, mode)
    _Xconst char* path;
    _Xconst char* mode;
{
    char buf[MAX_PATH];
    char* bufp = NULL;
    void* ret = NULL;
    UINT olderror = SetErrorMode (SEM_FAILCRITICALERRORS);

    if (AccessFile (path, buf, MAX_PATH, &bufp))
	ret = fopen (bufp, mode);

    (void) SetErrorMode (olderror);

    if (bufp != buf) Xfree (bufp);

    return ret;
}

int _XAccessFile(path)
    _Xconst char* path;
{
    char buf[MAX_PATH];
    char* bufp;
    int ret = -1;
    UINT olderror = SetErrorMode (SEM_FAILCRITICALERRORS);

    ret = AccessFile (path, buf, MAX_PATH, &bufp);

    (void) SetErrorMode (olderror);

    if (bufp != buf) Xfree (bufp);

    return ret;
}

#endif

#ifdef WIN32
#undef _Xdebug
int _Xdebug = 0;
int *_Xdebug_p = &_Xdebug;
void (**_XCreateMutex_fn_p)(LockInfoPtr) = &_XCreateMutex_fn;
void (**_XFreeMutex_fn_p)(LockInfoPtr) = &_XFreeMutex_fn;
void (**_XLockMutex_fn_p)(LockInfoPtr
#if defined(XTHREADS_WARN) || defined(XTHREADS_FILE_LINE)
    , char * /* file */
    , int /* line */
#endif
        ) = &_XLockMutex_fn;
void (**_XUnlockMutex_fn_p)(LockInfoPtr
#if defined(XTHREADS_WARN) || defined(XTHREADS_FILE_LINE)
    , char * /* file */
    , int /* line */
#endif
        ) = &_XUnlockMutex_fn;
LockInfoPtr *_Xglobal_lock_p = &_Xglobal_lock;
#endif