/* * $XConsortium: extutil.c,v 1.18 94/04/17 20:22:58 rws Exp $ * Copyright (c) 1989 X Consortium Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: 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 X CONSORTIUM 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 X Consortium 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 X Consortium. * * Author: Jim Fulton, MIT X Consortium * * * Xlib Extension-Writing Utilities * * This package contains utilities for writing the client API for various * protocol extensions. THESE INTERFACES ARE NOT PART OF THE X STANDARD AND * ARE SUBJECT TO CHANGE! * * Routines include: * * XextCreateExtension called once per extension * XextDestroyExtension if no longer using extension * XextAddDisplay add another display * XextRemoveDisplay remove a display * XextFindDisplay is a display open * * In addition, the following Xlib-style interfaces are provided: * * XSetExtensionErrorHandler establish an extension error handler * XMissingExtension raise an error about missing ext */ #include #include "Xlibint.h" #include "Xext.h" #include "extutil.h" /* * XextCreateExtension - return an extension descriptor containing context * information for this extension. This object is passed to all Xext * routines. */ XExtensionInfo *XextCreateExtension () { register XExtensionInfo *info = (XExtensionInfo *) Xmalloc (sizeof (XExtensionInfo)); if (info) { info->head = NULL; info->cur = NULL; info->ndisplays = 0; } return info; } /* * XextDestroyExtension - free memory the given extension descriptor */ void XextDestroyExtension (info) XExtensionInfo *info; { info->head = NULL; /* to catch refs after this */ info->cur = NULL; info->ndisplays = 0; XFree ((char *) info); } /* * XextAddDisplay - add a display to this extension */ XExtDisplayInfo *XextAddDisplay (extinfo, dpy, ext_name, hooks, nevents, data) XExtensionInfo *extinfo; Display *dpy; char *ext_name; XExtensionHooks *hooks; int nevents; XPointer data; { XExtDisplayInfo *dpyinfo; dpyinfo = (XExtDisplayInfo *) Xmalloc (sizeof (XExtDisplayInfo)); if (!dpyinfo) return NULL; dpyinfo->display = dpy; dpyinfo->data = data; dpyinfo->codes = XInitExtension (dpy, ext_name); /* * if the server has the extension, then we can initialize the * appropriate function vectors */ if (dpyinfo->codes) { int i, j; for (i = 0, j = dpyinfo->codes->first_event; i < nevents; i++, j++) { XESetWireToEvent (dpy, j, hooks->wire_to_event); XESetEventToWire (dpy, j, hooks->event_to_wire); } if (hooks->create_gc) XESetCreateGC (dpy, dpyinfo->codes->extension, hooks->create_gc); if (hooks->copy_gc) XESetCopyGC (dpy, dpyinfo->codes->extension, hooks->copy_gc); if (hooks->flush_gc) XESetFlushGC (dpy, dpyinfo->codes->extension, hooks->flush_gc); if (hooks->free_gc) XESetFreeGC (dpy, dpyinfo->codes->extension, hooks->free_gc); if (hooks->create_font) XESetCreateFont (dpy, dpyinfo->codes->extension, hooks->create_font); if (hooks->free_font) XESetFreeFont (dpy, dpyinfo->codes->extension, hooks->free_font); if (hooks->close_display) XESetCloseDisplay (dpy, dpyinfo->codes->extension, hooks->close_display); if (hooks->error) XESetError (dpy, dpyinfo->codes->extension, hooks->error); if (hooks->error_string) XESetErrorString (dpy, dpyinfo->codes->extension, hooks->error_string); } /* * now, chain it onto the list */ _XLockMutex(_Xglobal_lock); dpyinfo->next = extinfo->head; extinfo->head = dpyinfo; extinfo->cur = dpyinfo; extinfo->ndisplays++; _XUnlockMutex(_Xglobal_lock); return dpyinfo; } /* * XextRemoveDisplay - remove the indicated display from the extension object */ int XextRemoveDisplay (extinfo, dpy) XExtensionInfo *extinfo; Display *dpy; { XExtDisplayInfo *dpyinfo, *prev; /* * locate this display and its back link so that it can be removed */ _XLockMutex(_Xglobal_lock); prev = NULL; for (dpyinfo = extinfo->head; dpyinfo; dpyinfo = dpyinfo->next) { if (dpyinfo->display == dpy) break; prev = dpyinfo; } if (!dpyinfo) { _XUnlockMutex(_Xglobal_lock); return 0; /* hmm, actually an error */ } /* * remove the display from the list; handles going to zero */ if (prev) prev->next = dpyinfo->next; else extinfo->head = dpyinfo->next; extinfo->ndisplays--; if (dpyinfo == extinfo->cur) extinfo->cur = NULL; /* flush cache */ _XUnlockMutex(_Xglobal_lock); Xfree ((char *) dpyinfo); return 1; } /* * XextFindDisplay - look for a display in this extension; keeps a cache * of the most-recently used for efficiency. */ XExtDisplayInfo *XextFindDisplay (extinfo, dpy) XExtensionInfo *extinfo; Display *dpy; { register XExtDisplayInfo *dpyinfo; /* * see if this was the most recently accessed display */ if ((dpyinfo = extinfo->cur)&& dpyinfo->display == dpy) return dpyinfo; /* * look for display in list */ _XLockMutex(_Xglobal_lock); for (dpyinfo = extinfo->head; dpyinfo; dpyinfo = dpyinfo->next) { if (dpyinfo->display == dpy) { extinfo->cur = dpyinfo; /* cache most recently used */ _XUnlockMutex(_Xglobal_lock); return dpyinfo; } } _XUnlockMutex(_Xglobal_lock); return NULL; } static int _default_exterror (dpy, ext_name, reason) Display *dpy; char *ext_name; char *reason; { fprintf (stderr, "Xlib: extension \"%s\" %s on display \"%s\".\n", ext_name, reason, DisplayString(dpy)); return 0; } /* * XSetExtensionErrorHandler - sets the handler that gets called when a * requested extension is referenced. This should eventually move into Xlib. */ extern int (*_XExtensionErrorFunction)(); #if NeedFunctionPrototypes int (*XSetExtensionErrorHandler( int (*handler)( #if NeedNestedPrototypes Display*, char *, char * #endif ) ))() #else int (*XSetExtensionErrorHandler(handler))() int (*handler)(); #endif { int (*oldhandler)() = _XExtensionErrorFunction; _XExtensionErrorFunction = (handler ? handler : _default_exterror); return oldhandler; } /* * XMissingExtension - call the extension error handler */ #if NeedFunctionPrototypes int XMissingExtension ( Display *dpy, _Xconst char *ext_name) #else int XMissingExtension (dpy, ext_name) Display *dpy; char *ext_name; #endif { int (*func)() = (_XExtensionErrorFunction ? _XExtensionErrorFunction : _default_exterror); if (!ext_name) ext_name = X_EXTENSION_UNKNOWN; return (*func) (dpy, ext_name, X_EXTENSION_MISSING); }