1 /***********************************************************
2
3 Copyright 1987, 1998 The Open Group
4
5 Permission to use, copy, modify, distribute, and sell this software and its
6 documentation for any purpose is hereby granted without fee, provided that
7 the above copyright notice appear in all copies and that both that
8 copyright notice and this permission notice appear in supporting
9 documentation.
10
11 The above copyright notice and this permission notice shall be included in
12 all copies or substantial portions of the Software.
13
14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
18 AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
19 CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
20
21 Except as contained in this notice, the name of The Open Group shall not be
22 used in advertising or otherwise to promote the sale, use or other dealings
23 in this Software without prior written authorization from The Open Group.
24
25 Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
26
27 All Rights Reserved
28
29 Permission to use, copy, modify, and distribute this software and its
30 documentation for any purpose and without fee is hereby granted,
31 provided that the above copyright notice appear in all copies and that
32 both that copyright notice and this permission notice appear in
33 supporting documentation, and that the name of Digital not be
34 used in advertising or publicity pertaining to distribution of the
35 software without specific, written prior permission.
36
37 DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
38 ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
39 DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
40 ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
41 WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
42 ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
43 SOFTWARE.
44
45 ******************************************************************/
46
47 #ifdef HAVE_DIX_CONFIG_H
48 #include <dix-config.h>
49 #endif
50
51 #include <stdio.h>
52 #include <X11/X.h>
53 #include "os.h"
54 #include "osdep.h"
55 #include "opaque.h"
56 #include <X11/Xos.h>
57 #include <signal.h>
58 #include <errno.h>
59 #ifdef HAVE_DLFCN_H
60 #include <dlfcn.h>
61 #endif
62 #ifdef HAVE_BACKTRACE
63 #include <execinfo.h>
64 #endif
65
66 #include "misc.h"
67
68 #include "dixstruct.h"
69
70 #if !defined(SYSV) && !defined(WIN32)
71 #include <sys/resource.h>
72 #endif
73
74 #ifndef ADMPATH
75 #define ADMPATH "/usr/adm/X%smsgs"
76 #endif
77
78 #ifdef RLIMIT_DATA
79 int limitDataSpace = -1;
80 #endif
81 #ifdef RLIMIT_STACK
82 int limitStackSpace = -1;
83 #endif
84 #ifdef RLIMIT_NOFILE
85 int limitNoFile = -1;
86 #endif
87
88 /* The actual user defined max number of clients */
89 int LimitClients = LIMITCLIENTS;
90
91 static OsSigWrapperPtr OsSigWrapper = NULL;
92
93 OsSigWrapperPtr
OsRegisterSigWrapper(OsSigWrapperPtr newSigWrapper)94 OsRegisterSigWrapper(OsSigWrapperPtr newSigWrapper)
95 {
96 OsSigWrapperPtr oldSigWrapper = OsSigWrapper;
97
98 OsSigWrapper = newSigWrapper;
99
100 return oldSigWrapper;
101 }
102
103 /*
104 * OsSigHandler --
105 * Catch unexpected signals and exit or continue cleanly.
106 */
107 #if !defined(WIN32) || defined(__CYGWIN__)
108 static void
109 #ifdef SA_SIGINFO
OsSigHandler(int signo,siginfo_t * sip,void * unused)110 OsSigHandler(int signo, siginfo_t * sip, void *unused)
111 #else
112 OsSigHandler(int signo)
113 #endif
114 {
115 #ifdef RTLD_DI_SETSIGNAL
116 # define SIGNAL_FOR_RTLD_ERROR SIGQUIT
117 if (signo == SIGNAL_FOR_RTLD_ERROR) {
118 const char *dlerr = dlerror();
119
120 if (dlerr) {
121 LogMessageVerbSigSafe(X_ERROR, 1,
122 "Dynamic loader error: %s\n", dlerr);
123 }
124 }
125 #endif /* RTLD_DI_SETSIGNAL */
126
127 if (OsSigWrapper != NULL) {
128 if (OsSigWrapper(signo) == 0) {
129 /* ddx handled signal and wants us to continue */
130 return;
131 }
132 }
133
134 /* log, cleanup, and abort */
135 xorg_backtrace();
136
137 #ifdef SA_SIGINFO
138 if (sip->si_code == SI_USER) {
139 ErrorFSigSafe("Received signal %u sent by process %u, uid %u\n", signo,
140 sip->si_pid, sip->si_uid);
141 }
142 else {
143 switch (signo) {
144 case SIGSEGV:
145 case SIGBUS:
146 case SIGILL:
147 case SIGFPE:
148 ErrorFSigSafe("%s at address %p\n", strsignal(signo), sip->si_addr);
149 }
150 }
151 #endif
152
153 if (signo != SIGQUIT)
154 CoreDump = TRUE;
155
156 FatalError("Caught signal %d (%s). Server aborting\n",
157 signo, strsignal(signo));
158 }
159 #endif /* !WIN32 || __CYGWIN__ */
160
161 #include "busfault.h"
162
163 void
OsInit(void)164 OsInit(void)
165 {
166 static Bool been_here = FALSE;
167 #ifndef XQUARTZ
168 static const char *devnull = "/dev/null";
169 char fname[PATH_MAX];
170 #endif
171
172 if (!been_here) {
173 #if !defined(WIN32) || defined(__CYGWIN__)
174 struct sigaction act, oact;
175 int i;
176
177 int siglist[] = { SIGSEGV, SIGQUIT, SIGILL, SIGFPE, SIGBUS,
178 SIGABRT,
179 SIGSYS,
180 SIGXCPU,
181 SIGXFSZ,
182 #ifdef SIGEMT
183 SIGEMT,
184 #endif
185 0 /* must be last */
186 };
187 sigemptyset(&act.sa_mask);
188 #ifdef SA_SIGINFO
189 act.sa_sigaction = OsSigHandler;
190 act.sa_flags = SA_SIGINFO;
191 #else
192 act.sa_handler = OsSigHandler;
193 act.sa_flags = 0;
194 #endif
195 for (i = 0; siglist[i] != 0; i++) {
196 if (sigaction(siglist[i], &act, &oact)) {
197 ErrorF("failed to install signal handler for signal %d: %s\n",
198 siglist[i], strerror(errno));
199 }
200 }
201 #endif /* !WIN32 || __CYGWIN__ */
202 #ifdef BUSFAULT
203 busfault_init();
204 #endif
205 server_poll = ospoll_create();
206 if (!server_poll)
207 FatalError("failed to allocate poll structure");
208
209 #ifdef HAVE_BACKTRACE
210 /*
211 * initialize the backtracer, since the ctor calls dlopen(), which
212 * calls malloc(), which isn't signal-safe.
213 */
214 do {
215 void *array;
216
217 backtrace(&array, 1);
218 } while (0);
219 #endif
220
221 #ifdef RTLD_DI_SETSIGNAL
222 /* Tell runtime linker to send a signal we can catch instead of SIGKILL
223 * for failures to load libraries/modules at runtime so we can clean up
224 * after ourselves.
225 */
226 {
227 int failure_signal = SIGNAL_FOR_RTLD_ERROR;
228
229 dlinfo(RTLD_SELF, RTLD_DI_SETSIGNAL, &failure_signal);
230 }
231 #endif
232
233 #if !defined(XQUARTZ) /* STDIN is already /dev/null and STDOUT/STDERR is managed by console_redirect.c */
234 /*
235 * If a write of zero bytes to stderr returns non-zero, i.e. -1,
236 * then writing to stderr failed, and we'll write somewhere else
237 * instead. (Apparently this never happens in the Real World.)
238 */
239 if (write(2, fname, 0) == -1) {
240 FILE *err;
241
242 if (strlen(display) + strlen(ADMPATH) + 1 < sizeof fname)
243 snprintf(fname, sizeof(fname), ADMPATH, display);
244 else
245 strcpy(fname, devnull);
246 /*
247 * uses stdio to avoid os dependencies here,
248 * a real os would use
249 * open (fname, O_WRONLY|O_APPEND|O_CREAT, 0666)
250 */
251 if (!(err = fopen(fname, "a+")))
252 err = fopen(devnull, "w");
253 if (err && (fileno(err) != 2)) {
254 dup2(fileno(err), 2);
255 fclose(err);
256 }
257 #if defined(SYSV) || defined(SVR4) || defined(WIN32) || defined(__CYGWIN__)
258 {
259 static char buf[BUFSIZ];
260
261 setvbuf(stderr, buf, _IOLBF, BUFSIZ);
262 }
263 #else
264 setlinebuf(stderr);
265 #endif
266 }
267 #endif /* !XQUARTZ */
268
269 #if !defined(WIN32) || defined(__CYGWIN__)
270 if (getpgrp() == 0)
271 setpgid(0, 0);
272 #endif
273
274 #ifdef RLIMIT_DATA
275 if (limitDataSpace >= 0) {
276 struct rlimit rlim;
277
278 if (!getrlimit(RLIMIT_DATA, &rlim)) {
279 if ((limitDataSpace > 0) && (limitDataSpace < rlim.rlim_max))
280 rlim.rlim_cur = limitDataSpace;
281 else
282 rlim.rlim_cur = rlim.rlim_max;
283 (void) setrlimit(RLIMIT_DATA, &rlim);
284 }
285 }
286 #endif
287 #ifdef RLIMIT_STACK
288 if (limitStackSpace >= 0) {
289 struct rlimit rlim;
290
291 if (!getrlimit(RLIMIT_STACK, &rlim)) {
292 if ((limitStackSpace > 0) && (limitStackSpace < rlim.rlim_max))
293 rlim.rlim_cur = limitStackSpace;
294 else
295 rlim.rlim_cur = rlim.rlim_max;
296 (void) setrlimit(RLIMIT_STACK, &rlim);
297 }
298 }
299 #endif
300 #ifdef RLIMIT_NOFILE
301 if (limitNoFile >= 0) {
302 struct rlimit rlim;
303
304 if (!getrlimit(RLIMIT_NOFILE, &rlim)) {
305 if ((limitNoFile > 0) && (limitNoFile < rlim.rlim_max))
306 rlim.rlim_cur = limitNoFile;
307 else
308 rlim.rlim_cur = rlim.rlim_max;
309 (void) setrlimit(RLIMIT_NOFILE, &rlim);
310 }
311 }
312 #endif
313 LockServer();
314 been_here = TRUE;
315 }
316 TimerInit();
317 OsVendorInit();
318 OsResetSignals();
319 /*
320 * No log file by default. OsVendorInit() should call LogInit() with the
321 * log file name if logging to a file is desired.
322 */
323 LogInit(NULL, NULL);
324 SmartScheduleInit();
325 }
326
327 void
OsCleanup(Bool terminating)328 OsCleanup(Bool terminating)
329 {
330 if (terminating) {
331 UnlockServer();
332 }
333 }
334