#include "copyright.h"

/* $XConsortium: XInitExt.c,v 11.17 88/10/22 11:15:09 rws Exp $ */
/* Copyright  Massachusetts Institute of Technology 1987 */

#include "Xlibint.h"
#include <stdio.h>

extern Bool _XUnknownWireEvent ();
extern Status _XUnknownNativeEvent ();

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

XExtCodes *
XInitExtension (dpy, name)
  Display *dpy;
  char *name;
{
  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);
  ext = (_XExtension *) Xcalloc (1, sizeof (_XExtension));
  codes.extension = dpy->ext_number++;
  ext->codes = codes;

  /* 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);
  ext = (_XExtension *) Xcalloc (1, sizeof (_XExtension));
  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 (dpy, extension)
  register Display *dpy;	/* display */
  register int extension;	/* extension number */
{
  register _XExtension *ext = dpy->ext_procs;
  while (ext != NULL) {
    if (ext->codes.extension == extension)
      return (ext);
    ext = ext->next;
  }
  return (NULL);
}

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

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.
 */
int (*
     XESetCreateGC (dpy, extension, proc)) ()
  Display *dpy;			/* display */
  int extension;		/* extension number */
  int (*proc) ();		/* routine to call when GC created */
{
  register _XExtension *e;	/* for lookup of extension */
  register int (*oldproc) ();
  if ((e = XLookupExtension (dpy, extension)) == NULL)
    return (NULL);

  oldproc = e->create_GC;
  e->create_GC = proc;

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

  oldproc = e->copy_GC;
  e->copy_GC = proc;

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

  oldproc = e->flush_GC;
  e->flush_GC = proc;

  return (oldproc);
}

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

  oldproc = e->free_GC;
  e->free_GC = proc;

  return (oldproc);
}

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

  oldproc = e->create_Font;
  e->create_Font = proc;

  return (oldproc);
}

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

  oldproc = e->free_Font;
  e->free_Font = proc;

  return (oldproc);
}

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

  oldproc = e->close_display;
  e->close_display = proc;

  return (oldproc);
}

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

  return (oldproc);
}

Status (*XESetEventToWire (dpy, event_number, proc)) ()
  Display *dpy;			/* display */
Status (*proc) ();		/* routine to call when converting event */
  int event_number;		/* event routine to replace */
{
  register Status (*oldproc) ();
  if (proc == NULL)
    proc = _XUnknownNativeEvent;
  LockDisplay (dpy);
  oldproc = dpy->wire_vec[event_number];
  dpy->wire_vec[event_number] = proc;
  return (oldproc);
}
int (*
     XESetError (dpy, extension, proc)) ()
  Display *dpy;			/* display */
  int extension;		/* extension number */
  int (*proc) ();		/* routine to call when X error happens */
{
  register _XExtension *e;	/* for lookup of extension */
  register int (*oldproc) ();
  if ((e = XLookupExtension (dpy, extension)) == NULL)
    return (NULL);

  oldproc = e->error;
  e->error = proc;

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

  oldproc = e->error_string;
  e->error_string = proc;

  return (oldproc);
}