/* $Xorg: InitExt.c,v 1.4 2001/02/09 02:03:34 xorgcvs Exp $ */
/*

Copyright 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.

*/
/* $XFree86: xc/lib/X11/InitExt.c,v 1.7 2001/12/14 19:54:02 dawes Exp $ */

#include <X11/Xlibint.h>
#include <X11/Xos.h>
#include <stdio.h>

/*
 * This routine is used to link a extension in so it will be called
 * at appropriate times.
 */

#if NeedFunctionPrototypes
XExtCodes *XInitExtension (
	Display *dpy,
	_Xconst char *name)
#else
XExtCodes *XInitExtension (dpy, name)
	Display *dpy;
	char *name;
#endif
{
	XExtCodes codes;	/* temp. place for extension information. */
	register _XExtension *ext;/* need a place to build it all */
	if (!XQueryExtension(dpy, name, 
		&codes.major_opcode, &codes.first_event,
		&codes.first_error)) return (NULL);

	LockDisplay (dpy);
	if (! (ext = (_XExtension *) Xcalloc (1, sizeof (_XExtension))) ||
	    ! (ext->name = Xmalloc((unsigned) strlen(name) + 1))) {
	    if (ext) Xfree((char *) ext);
	    UnlockDisplay(dpy);
	    return (XExtCodes *) NULL;
	}
	codes.extension = dpy->ext_number++;
	ext->codes = codes;
	(void) strcpy(ext->name, name);

	/* chain it onto the display list */	
	ext->next = dpy->ext_procs;
	dpy->ext_procs = ext;
	UnlockDisplay (dpy);

	return (&ext->codes);		/* tell him which extension */
}

XExtCodes *XAddExtension (dpy)
    Display *dpy;
{
    register _XExtension *ext;

    LockDisplay (dpy);
    if (! (ext = (_XExtension *) Xcalloc (1, sizeof (_XExtension)))) {
	UnlockDisplay(dpy);
	return (XExtCodes *) NULL;
    }
    ext->codes.extension = dpy->ext_number++;

    /* chain it onto the display list */
    ext->next = dpy->ext_procs;
    dpy->ext_procs = ext;
    UnlockDisplay (dpy);

    return (&ext->codes);		/* tell him which extension */
}

static _XExtension *XLookupExtension (
	register Display *dpy,	/* display */
	register int extension)	/* extension number */
{
	register _XExtension *ext;
	for (ext = dpy->ext_procs; ext; ext = ext->next)
	    if (ext->codes.extension == extension) return (ext);
	return (NULL);
}

XExtData **XEHeadOfExtensionList(object)
    XEDataObject object;
{
    return *(XExtData ***)&object;
}

int
XAddToExtensionList(structure, ext_data)
    XExtData **structure;
    XExtData *ext_data;
{
    ext_data->next = *structure;
    *structure = ext_data;
    return 1;
}

XExtData *XFindOnExtensionList(structure, number)
    XExtData **structure;
    int number;
{
    XExtData *ext;

    ext = *structure;
    while (ext && (ext->number != number))
	ext = ext->next;
    return ext;
}

/*
 * Routines to hang procs on the extension structure.
 */
CreateGCType XESetCreateGC(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	CreateGCType proc;	/* routine to call when GC created */
{
	register _XExtension *e;	/* for lookup of extension */
	register CreateGCType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->create_GC;
	e->create_GC = proc;
	UnlockDisplay(dpy);
	return (CreateGCType)oldproc;
}

CopyGCType XESetCopyGC(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	CopyGCType proc;	/* routine to call when GC copied */
{
	register _XExtension *e;	/* for lookup of extension */
	register CopyGCType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->copy_GC;
	e->copy_GC = proc;
	UnlockDisplay(dpy);
	return (CopyGCType)oldproc;
}

FlushGCType XESetFlushGC(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	FlushGCType proc;	/* routine to call when GC copied */
{
	register _XExtension *e;	/* for lookup of extension */
	register FlushGCType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->flush_GC;
	e->flush_GC = proc;
	UnlockDisplay(dpy);
	return (FlushGCType)oldproc;
}

FreeGCType XESetFreeGC(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	FreeGCType proc;	/* routine to call when GC freed */
{
	register _XExtension *e;	/* for lookup of extension */
	register FreeGCType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->free_GC;
	e->free_GC = proc;
	UnlockDisplay(dpy);
	return (FreeGCType)oldproc;
}

CreateFontType XESetCreateFont(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	CreateFontType proc;	/* routine to call when font created */
{
	register _XExtension *e;	/* for lookup of extension */
	register CreateFontType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->create_Font;
	e->create_Font = proc;
	UnlockDisplay(dpy);
	return (CreateFontType)oldproc;
}

FreeFontType XESetFreeFont(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	FreeFontType proc;	/* routine to call when font freed */
{
	register _XExtension *e;	/* for lookup of extension */
	register FreeFontType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->free_Font;
	e->free_Font = proc;
	UnlockDisplay(dpy);
	return (FreeFontType)oldproc;
}

CloseDisplayType XESetCloseDisplay(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	CloseDisplayType proc;	/* routine to call when display closed */
{
	register _XExtension *e;	/* for lookup of extension */
	register CloseDisplayType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->close_display;
	e->close_display = proc;
	UnlockDisplay(dpy);
	return (CloseDisplayType)oldproc;
}

typedef Bool (*WireToEventType) (
#if NeedFunctionPrototypes
    Display*	/* display */,
    XEvent*	/* re */,
    xEvent*	/* event */
#endif
);

WireToEventType XESetWireToEvent(dpy, event_number, proc)
	Display *dpy;		/* display */
	WireToEventType proc;	/* routine to call when converting event */
	int event_number;	/* event routine to replace */
{
	register WireToEventType oldproc;
	if (proc == NULL) proc = (WireToEventType)_XUnknownWireEvent;
	LockDisplay (dpy);
	oldproc = dpy->event_vec[event_number];
	dpy->event_vec[event_number] = proc;
	UnlockDisplay (dpy);
	return (WireToEventType)oldproc;
}

typedef Status (*EventToWireType) (
#if NeedFunctionPrototypes
    Display*	/* display */,
    XEvent*	/* re */,
    xEvent*	/* event */
#endif
);

EventToWireType XESetEventToWire(dpy, event_number, proc)
	Display *dpy;		/* display */
	EventToWireType proc;	/* routine to call when converting event */
	int event_number;	/* event routine to replace */
{
	register EventToWireType oldproc;
	if (proc == NULL) proc = (EventToWireType) _XUnknownNativeEvent;
	LockDisplay (dpy);
	oldproc = dpy->wire_vec[event_number];
	dpy->wire_vec[event_number] = proc;
	UnlockDisplay(dpy);
	return (EventToWireType)oldproc;
}

typedef Bool (*WireToErrorType) (
#if NeedFunctionPrototypes
    Display*	/* display */,
    XErrorEvent* /* he */,
    xError*	/* we */
#endif
);

WireToErrorType XESetWireToError(dpy, error_number, proc)
	Display *dpy;		/* display */
	WireToErrorType proc;	/* routine to call when converting error */
	int error_number;	/* error routine to replace */
{
	register WireToErrorType oldproc = NULL;
	if (proc == NULL) proc = (WireToErrorType)_XDefaultWireError;
	LockDisplay (dpy);
	if (!dpy->error_vec) {
	    int i;
	    dpy->error_vec = Xmalloc(256 * sizeof(oldproc));
	    for (i = 1; i < 256; i++)
		dpy->error_vec[i] = _XDefaultWireError;
	}
	if (dpy->error_vec) {
	    oldproc = dpy->error_vec[error_number];
	    dpy->error_vec[error_number] = proc;
	}
	UnlockDisplay (dpy);
	return (WireToErrorType)oldproc;
}

ErrorType XESetError(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	ErrorType proc;		/* routine to call when X error happens */
{
	register _XExtension *e;	/* for lookup of extension */
	register ErrorType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->error;
	e->error = proc;
	UnlockDisplay(dpy);
	return (ErrorType)oldproc;
}

ErrorStringType XESetErrorString(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	ErrorStringType proc;	/* routine to call when I/O error happens */
{
	register _XExtension *e;	/* for lookup of extension */
	register ErrorStringType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->error_string;
	e->error_string = proc;
	UnlockDisplay(dpy);
	return (ErrorStringType)oldproc;
}

PrintErrorType XESetPrintErrorValues(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	PrintErrorType proc;	/* routine to call to print */
{
	register _XExtension *e;	/* for lookup of extension */
	register PrintErrorType oldproc;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->error_values;
	e->error_values = proc;
	UnlockDisplay(dpy);
	return (PrintErrorType)oldproc;
}

BeforeFlushType XESetBeforeFlush(dpy, extension, proc)
	Display *dpy;		/* display */
	int extension;		/* extension number */
	BeforeFlushType proc;	/* routine to call on flush */
{
	register _XExtension *e;	/* for lookup of extension */
	register BeforeFlushType oldproc;
	register _XExtension *ext;
	if ((e = XLookupExtension (dpy, extension)) == NULL) return (NULL);
	LockDisplay(dpy);
	oldproc = e->before_flush;
	e->before_flush = proc;
	for (ext = dpy->flushes; ext && ext != e; ext = ext->next)
	    ;
	if (!ext) {
	    e->next_flush = dpy->flushes;
	    dpy->flushes = e;
	}	    
	UnlockDisplay(dpy);
	return (BeforeFlushType)oldproc;
}
