Bug Summary

File:GCManager.c
Location:line 311, column 11
Description:Dereference of null pointer

Annotated Source Code

1/***********************************************************
2Copyright (c) 1993, Oracle and/or its affiliates. All rights reserved.
3
4Permission is hereby granted, free of charge, to any person obtaining a
5copy of this software and associated documentation files (the "Software"),
6to deal in the Software without restriction, including without limitation
7the rights to use, copy, modify, merge, publish, distribute, sublicense,
8and/or sell copies of the Software, and to permit persons to whom the
9Software is furnished to do so, subject to the following conditions:
10
11The above copyright notice and this permission notice (including the next
12paragraph) shall be included in all copies or substantial portions of the
13Software.
14
15THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21DEALINGS IN THE SOFTWARE.
22
23Copyright 1987, 1988, 1990 by Digital Equipment Corporation, Maynard, Massachusetts.
24
25 All Rights Reserved
26
27Permission to use, copy, modify, and distribute this software and its
28documentation for any purpose and without fee is hereby granted,
29provided that the above copyright notice appear in all copies and that
30both that copyright notice and this permission notice appear in
31supporting documentation, and that the name of Digital not be
32used in advertising or publicity pertaining to distribution of the
33software without specific, written prior permission.
34
35DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
36ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
37DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
38ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
39WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
40ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
41SOFTWARE.
42
43******************************************************************/
44
45/*
46
47Copyright 1987, 1988, 1990, 1994, 1998 The Open Group
48
49Permission to use, copy, modify, distribute, and sell this software and its
50documentation for any purpose is hereby granted without fee, provided that
51the above copyright notice appear in all copies and that both that
52copyright notice and this permission notice appear in supporting
53documentation.
54
55The above copyright notice and this permission notice shall be included in
56all copies or substantial portions of the Software.
57
58THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
59IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
60FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
61OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
62AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
63CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
64
65Except as contained in this notice, the name of The Open Group shall not be
66used in advertising or otherwise to promote the sale, use or other dealings
67in this Software without prior written authorization from The Open Group.
68
69*/
70
71#ifdef HAVE_CONFIG_H1
72#include <config.h>
73#endif
74#include "IntrinsicI.h"
75
76
77typedef struct _GCrec {
78 unsigned char screen; /* Screen for GC */
79 unsigned char depth; /* Depth for GC */
80 char dashes; /* Dashes value */
81 Pixmap clip_mask; /* Clip_mask value */
82 Cardinal ref_count; /* # of shareholders */
83 GC gc; /* The GC itself. */
84 XtGCMask dynamic_mask; /* Writable values */
85 XtGCMask unused_mask; /* Unused values */
86 struct _GCrec *next; /* Next GC for this widgetkind. */
87} GCrec, *GCptr;
88
89#define GCVAL(bit,mask,val,default)((bit&mask) ? val : default) ((bit&mask) ? val : default)
90
91#define CHECK(bit,comp,default)if ((checkMask & bit) && (((bit&valueMask) ? v
->comp : default) != gcv.comp)) return 0 \
92 if ((checkMask & bit) && \
93 (GCVAL(bit,valueMask,v->comp,default)((bit&valueMask) ? v->comp : default) != gcv.comp)) return False0
94
95#define ALLGCVALS((1L<<0) | (1L<<1) | (1L<<2) | (1L<<3
) | (1L<<4) | (1L<<5) | (1L<<6) | (1L<<
7) | (1L<<8) | (1L<<9) | (1L<<10) | (1L<<
11) | (1L<<12) | (1L<<13) | (1L<<14) | (1L<<
15) | (1L<<16) | (1L<<17) | (1L<<18) | (1L<<
20) | (1L<<22)) (GCFunction(1L<<0) | GCPlaneMask(1L<<1) | GCForeground(1L<<2) | \
96 GCBackground(1L<<3) | GCLineWidth(1L<<4) | GCLineStyle(1L<<5) | \
97 GCCapStyle(1L<<6) | GCJoinStyle(1L<<7) | GCFillStyle(1L<<8) | \
98 GCFillRule(1L<<9) | GCTile(1L<<10) | GCStipple(1L<<11) | \
99 GCTileStipXOrigin(1L<<12) | GCTileStipYOrigin(1L<<13) | \
100 GCFont(1L<<14) | GCSubwindowMode(1L<<15) | GCGraphicsExposures(1L<<16) | \
101 GCClipXOrigin(1L<<17) | GCClipYOrigin(1L<<18) | GCDashOffset(1L<<20) | \
102 GCArcMode(1L<<22))
103
104static Boolint Matches(
105 Display *dpy,
106 GCptr ptr,
107 register XtGCMask valueMask,
108 register XGCValues *v,
109 XtGCMask readOnlyMask,
110 XtGCMask dynamicMask)
111{
112 XGCValues gcv;
113 register XtGCMask checkMask;
114
115 if (readOnlyMask & ptr->dynamic_mask)
116 return False0;
117 if (((ptr->dynamic_mask|ptr->unused_mask) & dynamicMask) != dynamicMask)
118 return False0;
119 if (!XGetGCValues(dpy, ptr->gc, ALLGCVALS((1L<<0) | (1L<<1) | (1L<<2) | (1L<<3
) | (1L<<4) | (1L<<5) | (1L<<6) | (1L<<
7) | (1L<<8) | (1L<<9) | (1L<<10) | (1L<<
11) | (1L<<12) | (1L<<13) | (1L<<14) | (1L<<
15) | (1L<<16) | (1L<<17) | (1L<<18) | (1L<<
20) | (1L<<22)), &gcv))
120 return False0;
121 checkMask = readOnlyMask & ~ptr->unused_mask;
122 CHECK(GCForeground, foreground, 0)if ((checkMask & (1L<<2)) && ((((1L<<
2)&valueMask) ? v->foreground : 0) != gcv.foreground))
return 0;
123 CHECK(GCBackground, background, 1)if ((checkMask & (1L<<3)) && ((((1L<<
3)&valueMask) ? v->background : 1) != gcv.background))
return 0;
124 CHECK(GCFont, font, ~0UL)if ((checkMask & (1L<<14)) && ((((1L<<
14)&valueMask) ? v->font : ~0UL) != gcv.font)) return 0;
125 CHECK(GCFillStyle, fill_style, FillSolid)if ((checkMask & (1L<<8)) && ((((1L<<
8)&valueMask) ? v->fill_style : 0) != gcv.fill_style))
return 0;
126 CHECK(GCLineWidth, line_width, 0)if ((checkMask & (1L<<4)) && ((((1L<<
4)&valueMask) ? v->line_width : 0) != gcv.line_width))
return 0;
127 CHECK(GCFunction, function, GXcopy)if ((checkMask & (1L<<0)) && ((((1L<<
0)&valueMask) ? v->function : 0x3) != gcv.function)) return
0;
128 CHECK(GCGraphicsExposures, graphics_exposures, True)if ((checkMask & (1L<<16)) && ((((1L<<
16)&valueMask) ? v->graphics_exposures : 1) != gcv.graphics_exposures
)) return 0;
129 CHECK(GCTile, tile, ~0UL)if ((checkMask & (1L<<10)) && ((((1L<<
10)&valueMask) ? v->tile : ~0UL) != gcv.tile)) return 0;
130 CHECK(GCSubwindowMode, subwindow_mode, ClipByChildren)if ((checkMask & (1L<<15)) && ((((1L<<
15)&valueMask) ? v->subwindow_mode : 0) != gcv.subwindow_mode
)) return 0;
131 CHECK(GCPlaneMask, plane_mask, AllPlanes)if ((checkMask & (1L<<1)) && ((((1L<<
1)&valueMask) ? v->plane_mask : ((unsigned long)~0L)) !=
gcv.plane_mask)) return 0;
132 CHECK(GCLineStyle, line_style, LineSolid)if ((checkMask & (1L<<5)) && ((((1L<<
5)&valueMask) ? v->line_style : 0) != gcv.line_style))
return 0;
133 CHECK(GCCapStyle, cap_style, CapButt)if ((checkMask & (1L<<6)) && ((((1L<<
6)&valueMask) ? v->cap_style : 1) != gcv.cap_style)) return
0;
134 CHECK(GCJoinStyle, join_style, JoinMiter)if ((checkMask & (1L<<7)) && ((((1L<<
7)&valueMask) ? v->join_style : 0) != gcv.join_style))
return 0;
135 CHECK(GCFillRule, fill_rule, EvenOddRule)if ((checkMask & (1L<<9)) && ((((1L<<
9)&valueMask) ? v->fill_rule : 0) != gcv.fill_rule)) return
0;
136 CHECK(GCArcMode, arc_mode, ArcPieSlice)if ((checkMask & (1L<<22)) && ((((1L<<
22)&valueMask) ? v->arc_mode : 1) != gcv.arc_mode)) return
0;
137 CHECK(GCStipple, stipple, ~0UL)if ((checkMask & (1L<<11)) && ((((1L<<
11)&valueMask) ? v->stipple : ~0UL) != gcv.stipple)) return
0;
138 CHECK(GCTileStipXOrigin, ts_x_origin, 0)if ((checkMask & (1L<<12)) && ((((1L<<
12)&valueMask) ? v->ts_x_origin : 0) != gcv.ts_x_origin
)) return 0;
139 CHECK(GCTileStipYOrigin, ts_y_origin, 0)if ((checkMask & (1L<<13)) && ((((1L<<
13)&valueMask) ? v->ts_y_origin : 0) != gcv.ts_y_origin
)) return 0;
140 CHECK(GCClipXOrigin, clip_x_origin, 0)if ((checkMask & (1L<<17)) && ((((1L<<
17)&valueMask) ? v->clip_x_origin : 0) != gcv.clip_x_origin
)) return 0;
141 CHECK(GCClipYOrigin, clip_y_origin, 0)if ((checkMask & (1L<<18)) && ((((1L<<
18)&valueMask) ? v->clip_y_origin : 0) != gcv.clip_y_origin
)) return 0;
142 CHECK(GCDashOffset, dash_offset, 0)if ((checkMask & (1L<<20)) && ((((1L<<
20)&valueMask) ? v->dash_offset : 0) != gcv.dash_offset
)) return 0;
143 gcv.clip_mask = ptr->clip_mask;
144 CHECK(GCClipMask, clip_mask, None)if ((checkMask & (1L<<19)) && ((((1L<<
19)&valueMask) ? v->clip_mask : 0L) != gcv.clip_mask))
return 0;
145 gcv.dashes = ptr->dashes;
146 CHECK(GCDashList, dashes, 4)if ((checkMask & (1L<<21)) && ((((1L<<
21)&valueMask) ? v->dashes : 4) != gcv.dashes)) return
0;
147 valueMask &= ptr->unused_mask | dynamicMask;
148 if (valueMask) {
149 XChangeGC(dpy, ptr->gc, valueMask, v);
150 if (valueMask & GCDashList(1L<<21))
151 ptr->dashes = v->dashes;
152 if (valueMask & GCClipMask(1L<<19))
153 ptr->clip_mask = v->clip_mask;
154 }
155 ptr->unused_mask &= ~(dynamicMask | readOnlyMask);
156 ptr->dynamic_mask |= dynamicMask;
157 return True1;
158} /* Matches */
159
160/* Called by CloseDisplay to free the per-display GC list */
161void _XtGClistFree(
162 Display *dpy,
163 register XtPerDisplay pd)
164{
165 register GCptr GClist, next;
166 register int i;
167
168 GClist = pd->GClist;
169 while (GClist) {
170 next = GClist->next;
171 XtFree((char*)GClist);
172 GClist = next;
173 }
174 if (pd->pixmap_tab) {
175 for (i = ScreenCount(dpy)(((_XPrivDisplay)dpy)->nscreens); --i >= 0; ) {
176 if (pd->pixmap_tab[i])
177 XtFree((char *)pd->pixmap_tab[i]);
178 }
179 XtFree((char *)pd->pixmap_tab);
180 }
181}
182
183
184/*
185 * Return a GC with the given values and characteristics.
186 */
187
188GC XtAllocateGC(
189 register Widget widget,
190 Cardinal depth,
191 XtGCMask valueMask,
192 XGCValues *values,
193 XtGCMask dynamicMask,
194 XtGCMask unusedMask)
195{
196 register GCptr *prev;
197 register GCptr cur;
198 Screen *screen;
199 register Display *dpy;
200 register XtPerDisplay pd;
201 Drawable drawable;
202 Drawable *pixmaps;
203 XtGCMask readOnlyMask;
204 GC retval;
205 WIDGET_TO_APPCON(widget)XtAppContext app = (widget && _XtProcessLock ? XtWidgetToApplicationContext
(widget) : ((void*)0));
206
207 LOCK_APP(app)if(app && app->lock)(*app->lock)(app);
208 LOCK_PROCESSif(_XtProcessLock)(*_XtProcessLock)();
209 if (!XtIsWidget(widget)(((Object)(widget))->object.widget_class->core_class.class_inited
& 0x04))
210 widget = _XtWindowedAncestor(widget);
211 if (!depth)
212 depth = widget->core.depth;
213 screen = XtScreen(widget)((widget)->core.screen);
214 dpy = DisplayOfScreen(screen)((screen)->display);
215 pd = _XtGetPerDisplay(dpy);
216 unusedMask &= ~valueMask;
217 readOnlyMask = ~(dynamicMask | unusedMask);
218
219 /* Search for existing GC that matches exactly */
220 for (prev = &pd->GClist; (cur = *prev); prev = &cur->next) {
221 if (cur->depth == depth &&
222 ScreenOfDisplay(dpy, cur->screen)(&((_XPrivDisplay)dpy)->screens[cur->screen]) == screen &&
223 Matches(dpy, cur, valueMask, values, readOnlyMask, dynamicMask)) {
224 cur->ref_count++;
225 /* Move this GC to front of list */
226 *prev = cur->next;
227 cur->next = pd->GClist;
228 pd->GClist = cur;
229 retval = cur->gc;
230 UNLOCK_PROCESSif(_XtProcessUnlock)(*_XtProcessUnlock)();
231 UNLOCK_APP(app)if(app && app->unlock)(*app->unlock)(app);
232 return retval;
233 }
234 }
235
236 /* No matches, have to create a new one */
237 cur = XtNew(GCrec)((GCrec *) XtMalloc((unsigned) sizeof(GCrec)));
238 cur->screen = XScreenNumberOfScreen(screen);
239 cur->depth = depth;
240 cur->ref_count = 1;
241 cur->dynamic_mask = dynamicMask;
242 cur->unused_mask = (unusedMask & ~dynamicMask);
243 cur->dashes = GCVAL(GCDashList, valueMask, values->dashes, 4)(((1L<<21)&valueMask) ? values->dashes : 4);
244 cur->clip_mask = GCVAL(GCClipMask, valueMask, values->clip_mask, None)(((1L<<19)&valueMask) ? values->clip_mask : 0L);
245 drawable = 0;
246 if (depth == widget->core.depth)
247 drawable = XtWindow(widget)((widget)->core.window);
248 if (!drawable && depth == (Cardinal) DefaultDepthOfScreen(screen)((screen)->root_depth))
249 drawable = RootWindowOfScreen(screen)((screen)->root);
250 if (!drawable) {
251 if (!pd->pixmap_tab) {
252 int n;
253 pd->pixmap_tab = (Drawable **)__XtMalloc((unsigned)ScreenCount(dpy)(((_XPrivDisplay)dpy)->nscreens) *
254 sizeof(Drawable *));
255 for (n = 0; n < ScreenCount(dpy)(((_XPrivDisplay)dpy)->nscreens); n++)
256 pd->pixmap_tab[n] = NULL((void*)0);
257 }
258 pixmaps = pd->pixmap_tab[cur->screen];
259 if (!pixmaps) {
260 int max, n, *depths;
261 depths = XListDepths(dpy, cur->screen, &n);
262 n--;
263 max = depths[n];
264 while (n--) {
265 if (depths[n] > max)
266 max = depths[n];
267 }
268 XFree((char *)depths);
269 pixmaps = (Drawable *)__XtCalloc((unsigned)max, sizeof(Drawable));
270 pd->pixmap_tab[cur->screen] = pixmaps;
271 }
272 drawable = pixmaps[cur->depth - 1];
273 if (!drawable) {
274 drawable = XCreatePixmap(dpy, RootWindowOfScreen(screen)((screen)->root), 1, 1,
275 cur->depth);
276 pixmaps[cur->depth - 1] = drawable;
277 }
278 }
279 cur->gc = XCreateGC(dpy, drawable, valueMask, values);
280 cur->next = pd->GClist;
281 pd->GClist = cur;
282 retval = cur->gc;
283 UNLOCK_PROCESSif(_XtProcessUnlock)(*_XtProcessUnlock)();
284 UNLOCK_APP(app)if(app && app->unlock)(*app->unlock)(app);
285 return retval;
286} /* XtAllocateGC */
287
288/*
289 * Return a read-only GC with the given values.
290 */
291
292GC XtGetGC(
293 register Widget widget,
294 XtGCMask valueMask,
295 XGCValues *values)
296{
297 return XtAllocateGC(widget, 0, valueMask, values, 0, 0);
298} /* XtGetGC */
299
300void XtReleaseGC(
301 Widget widget,
302 register GC gc)
303{
304 register GCptr cur, *prev;
305 Display* dpy;
306 XtPerDisplay pd;
307 WIDGET_TO_APPCON(widget)XtAppContext app = (widget && _XtProcessLock ? XtWidgetToApplicationContext
(widget) : ((void*)0));
308
309 LOCK_APP(app)if(app && app->lock)(*app->lock)(app);
310 LOCK_PROCESSif(_XtProcessLock)(*_XtProcessLock)();
1
Within the expansion of the macro 'LOCK_PROCESS':
a
Assuming '_XtProcessLock' is null
311 dpy = XtDisplayOfObject(widget)((((Object)(widget))->object.widget_class->core_class.class_inited
& 0x04) ? (widget)->core.screen->display : _XtIsHookObject
(widget) ? ((HookObject)(widget))->hooks.screen->display
: _XtWindowedAncestor(widget)->core.screen->display);
2
Within the expansion of the macro 'XtDisplayOfObject':
a
Dereference of null pointer
312 pd = _XtGetPerDisplay(dpy);
313
314 for (prev = &pd->GClist; (cur = *prev); prev = &cur->next) {
315 if (cur->gc == gc) {
316 if (--(cur->ref_count) == 0) {
317 *prev = cur->next;
318 XFreeGC(dpy, gc);
319 XtFree((char *) cur);
320 }
321 break;
322 }
323 }
324 UNLOCK_PROCESSif(_XtProcessUnlock)(*_XtProcessUnlock)();
325 UNLOCK_APP(app)if(app && app->unlock)(*app->unlock)(app);
326} /* XtReleaseGC */
327
328/* The following interface is broken and supplied only for backwards
329 * compatibility. It will work properly in all cases only if there
330 * is exactly 1 Display created by the application.
331 */
332
333void XtDestroyGC(register GC gc)
334{
335 GCptr cur, *prev;
336 XtAppContext app;
337
338 LOCK_PROCESSif(_XtProcessLock)(*_XtProcessLock)();
339 app = _XtGetProcessContext()->appContextList;
340 /* This is awful; we have to search through all the lists
341 to find the GC. */
342 for (; app; app = app->next) {
343 int i;
344 for (i = app->count; i ;) {
345 Display *dpy = app->list[--i];
346 XtPerDisplay pd = _XtGetPerDisplay(dpy);
347 for (prev = &pd->GClist; (cur = *prev); prev = &cur->next) {
348 if (cur->gc == gc) {
349 if (--(cur->ref_count) == 0) {
350 *prev = cur->next;
351 XFreeGC(dpy, gc);
352 XtFree((char *) cur);
353 }
354 UNLOCK_PROCESSif(_XtProcessUnlock)(*_XtProcessUnlock)();
355 return;
356 }
357 }
358 }
359 }
360 UNLOCK_PROCESSif(_XtProcessUnlock)(*_XtProcessUnlock)();
361} /* XtDestroyGC */