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bfff8b1b | 1 | /* Copyright (C) 1991-2017 Free Software Foundation, Inc. |
2c6fe0bd | 2 | This file is part of the GNU C Library. |
28f540f4 | 3 | |
2c6fe0bd | 4 | The GNU C Library is free software; you can redistribute it and/or |
41bdb6e2 AJ |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either | |
7 | version 2.1 of the License, or (at your option) any later version. | |
28f540f4 | 8 | |
2c6fe0bd UD |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
41bdb6e2 | 12 | Lesser General Public License for more details. |
28f540f4 | 13 | |
41bdb6e2 | 14 | You should have received a copy of the GNU Lesser General Public |
59ba27a6 PE |
15 | License along with the GNU C Library; if not, see |
16 | <http://www.gnu.org/licenses/>. */ | |
28f540f4 | 17 | |
28f540f4 | 18 | #include <stdio.h> |
64659255 | 19 | #include <stdlib.h> |
28f540f4 | 20 | #include <string.h> |
64659255 MK |
21 | |
22 | #include <cthreads.h> /* For `struct mutex'. */ | |
23 | #include <mach.h> | |
24 | #include <mach/thread_switch.h> | |
25 | ||
26 | #include <hurd.h> | |
762a2918 | 27 | #include <hurd/id.h> |
64659255 MK |
28 | #include <hurd/signal.h> |
29 | ||
28f540f4 RM |
30 | #include "hurdfault.h" |
31 | #include "hurdmalloc.h" /* XXX */ | |
cc13edc8 | 32 | #include "../locale/localeinfo.h" |
28f540f4 RM |
33 | |
34 | const char *_hurdsig_getenv (const char *); | |
35 | ||
36 | struct mutex _hurd_siglock; | |
37 | int _hurd_stopped; | |
38 | ||
39 | /* Port that receives signals and other miscellaneous messages. */ | |
40 | mach_port_t _hurd_msgport; | |
41 | ||
42 | /* Thread listening on it. */ | |
43 | thread_t _hurd_msgport_thread; | |
44 | ||
45 | /* Thread which receives task-global signals. */ | |
46 | thread_t _hurd_sigthread; | |
47 | ||
6bac11d9 MB |
48 | /* These are set up by _hurdsig_init. */ |
49 | unsigned long int __hurd_sigthread_stack_base; | |
50 | unsigned long int __hurd_sigthread_stack_end; | |
51 | unsigned long int *__hurd_sigthread_variables; | |
52 | ||
28f540f4 RM |
53 | /* Linked-list of per-thread signal state. */ |
54 | struct hurd_sigstate *_hurd_sigstates; | |
54da5be3 RM |
55 | |
56 | /* Timeout for RPC's after interrupt_operation. */ | |
57 | mach_msg_timeout_t _hurd_interrupted_rpc_timeout = 3000; | |
28f540f4 RM |
58 | \f |
59 | static void | |
60 | default_sigaction (struct sigaction actions[NSIG]) | |
61 | { | |
62 | int signo; | |
63 | ||
64 | __sigemptyset (&actions[0].sa_mask); | |
65 | actions[0].sa_flags = SA_RESTART; | |
66 | actions[0].sa_handler = SIG_DFL; | |
67 | ||
68 | for (signo = 1; signo < NSIG; ++signo) | |
69 | actions[signo] = actions[0]; | |
70 | } | |
71 | ||
72 | struct hurd_sigstate * | |
73 | _hurd_thread_sigstate (thread_t thread) | |
74 | { | |
75 | struct hurd_sigstate *ss; | |
76 | __mutex_lock (&_hurd_siglock); | |
77 | for (ss = _hurd_sigstates; ss != NULL; ss = ss->next) | |
78 | if (ss->thread == thread) | |
b96bdcd7 | 79 | break; |
28f540f4 RM |
80 | if (ss == NULL) |
81 | { | |
82 | ss = malloc (sizeof (*ss)); | |
83 | if (ss == NULL) | |
84 | __libc_fatal ("hurd: Can't allocate thread sigstate\n"); | |
85 | ss->thread = thread; | |
86 | __spin_lock_init (&ss->lock); | |
87 | ||
6df1b247 | 88 | /* Initialize default state. */ |
28f540f4 RM |
89 | __sigemptyset (&ss->blocked); |
90 | __sigemptyset (&ss->pending); | |
91 | memset (&ss->sigaltstack, 0, sizeof (ss->sigaltstack)); | |
10dc2a90 | 92 | ss->preemptors = NULL; |
e8bceaee | 93 | ss->suspended = MACH_PORT_NULL; |
28f540f4 RM |
94 | ss->intr_port = MACH_PORT_NULL; |
95 | ss->context = NULL; | |
96 | ||
97 | /* Initialize the sigaction vector from the default signal receiving | |
98 | thread's state, and its from the system defaults. */ | |
99 | if (thread == _hurd_sigthread) | |
100 | default_sigaction (ss->actions); | |
101 | else | |
102 | { | |
103 | struct hurd_sigstate *s; | |
104 | for (s = _hurd_sigstates; s != NULL; s = s->next) | |
105 | if (s->thread == _hurd_sigthread) | |
106 | break; | |
107 | if (s) | |
108 | { | |
109 | __spin_lock (&s->lock); | |
110 | memcpy (ss->actions, s->actions, sizeof (s->actions)); | |
111 | __spin_unlock (&s->lock); | |
112 | } | |
113 | else | |
114 | default_sigaction (ss->actions); | |
115 | } | |
116 | ||
117 | ss->next = _hurd_sigstates; | |
118 | _hurd_sigstates = ss; | |
119 | } | |
120 | __mutex_unlock (&_hurd_siglock); | |
121 | return ss; | |
122 | } | |
123 | \f | |
124 | /* Signal delivery itself is on this page. */ | |
125 | ||
126 | #include <hurd/fd.h> | |
9fd18b6c | 127 | #include <hurd/crash.h> |
79c236ac | 128 | #include <hurd/resource.h> |
28f540f4 RM |
129 | #include <hurd/paths.h> |
130 | #include <setjmp.h> | |
131 | #include <fcntl.h> | |
132 | #include <sys/wait.h> | |
8f480b4b | 133 | #include <thread_state.h> |
28f540f4 RM |
134 | #include <hurd/msg_server.h> |
135 | #include <hurd/msg_reply.h> /* For __msg_sig_post_reply. */ | |
28f540f4 | 136 | #include <hurd/interrupt.h> |
fb8e70d6 RM |
137 | #include <assert.h> |
138 | #include <unistd.h> | |
28f540f4 | 139 | |
28f540f4 | 140 | |
9fd18b6c | 141 | /* Call the crash dump server to mummify us before we die. |
28f540f4 RM |
142 | Returns nonzero if a core file was written. */ |
143 | static int | |
0e3426bb | 144 | write_corefile (int signo, const struct hurd_signal_detail *detail) |
28f540f4 RM |
145 | { |
146 | error_t err; | |
147 | mach_port_t coreserver; | |
148 | file_t file, coredir; | |
149 | const char *name; | |
150 | ||
79c236ac RM |
151 | /* Don't bother locking since we just read the one word. */ |
152 | rlim_t corelimit = _hurd_rlimits[RLIMIT_CORE].rlim_cur; | |
153 | ||
154 | if (corelimit == 0) | |
155 | /* No core dumping, thank you very much. Note that this makes | |
156 | `ulimit -c 0' prevent crash-suspension too, which is probably | |
157 | what the user wanted. */ | |
158 | return 0; | |
159 | ||
28f540f4 RM |
160 | /* XXX RLIMIT_CORE: |
161 | When we have a protocol to make the server return an error | |
162 | for RLIMIT_FSIZE, then tell the corefile fs server the RLIMIT_CORE | |
163 | value in place of the RLIMIT_FSIZE value. */ | |
164 | ||
165 | /* First get a port to the core dumping server. */ | |
166 | coreserver = MACH_PORT_NULL; | |
9fd18b6c | 167 | name = _hurdsig_getenv ("CRASHSERVER"); |
28f540f4 RM |
168 | if (name != NULL) |
169 | coreserver = __file_name_lookup (name, 0, 0); | |
170 | if (coreserver == MACH_PORT_NULL) | |
9fd18b6c | 171 | coreserver = __file_name_lookup (_SERVERS_CRASH, 0, 0); |
28f540f4 RM |
172 | if (coreserver == MACH_PORT_NULL) |
173 | return 0; | |
174 | ||
175 | /* Get a port to the directory where the new core file will reside. */ | |
78abf563 | 176 | file = MACH_PORT_NULL; |
28f540f4 RM |
177 | name = _hurdsig_getenv ("COREFILE"); |
178 | if (name == NULL) | |
179 | name = "core"; | |
180 | coredir = __file_name_split (name, (char **) &name); | |
78abf563 TBB |
181 | if (coredir != MACH_PORT_NULL) |
182 | /* Create the new file, but don't link it into the directory yet. */ | |
183 | __dir_mkfile (coredir, O_WRONLY|O_CREAT, | |
184 | 0600 & ~_hurd_umask, /* XXX ? */ | |
0f110f41 | 185 | &file); |
28f540f4 RM |
186 | |
187 | /* Call the core dumping server to write the core file. */ | |
9fd18b6c RM |
188 | err = __crash_dump_task (coreserver, |
189 | __mach_task_self (), | |
0e3426bb RM |
190 | file, |
191 | signo, detail->code, detail->error, | |
192 | detail->exc, detail->exc_code, detail->exc_subcode, | |
193 | _hurd_ports[INIT_PORT_CTTYID].port, | |
194 | MACH_MSG_TYPE_COPY_SEND); | |
28f540f4 | 195 | __mach_port_deallocate (__mach_task_self (), coreserver); |
78abf563 TBB |
196 | |
197 | if (! err && file != MACH_PORT_NULL) | |
28f540f4 RM |
198 | /* The core dump into FILE succeeded, so now link it into the |
199 | directory. */ | |
70481be8 | 200 | err = __dir_link (coredir, file, name, 1); |
28f540f4 RM |
201 | __mach_port_deallocate (__mach_task_self (), file); |
202 | __mach_port_deallocate (__mach_task_self (), coredir); | |
78abf563 | 203 | return !err && file != MACH_PORT_NULL; |
28f540f4 RM |
204 | } |
205 | ||
206 | ||
28f540f4 RM |
207 | /* The lowest-numbered thread state flavor value is 1, |
208 | so we use bit 0 in machine_thread_all_state.set to | |
209 | record whether we have done thread_abort. */ | |
210 | #define THREAD_ABORTED 1 | |
211 | ||
1a3a58fd | 212 | /* SS->thread is suspended. Abort the thread and get its basic state. */ |
28f540f4 RM |
213 | static void |
214 | abort_thread (struct hurd_sigstate *ss, struct machine_thread_all_state *state, | |
1a3a58fd | 215 | void (*reply) (void)) |
28f540f4 RM |
216 | { |
217 | if (!(state->set & THREAD_ABORTED)) | |
218 | { | |
b96bdcd7 RM |
219 | error_t err = __thread_abort (ss->thread); |
220 | assert_perror (err); | |
28f540f4 RM |
221 | /* Clear all thread state flavor set bits, because thread_abort may |
222 | have changed the state. */ | |
223 | state->set = THREAD_ABORTED; | |
224 | } | |
225 | ||
1a3a58fd RM |
226 | if (reply) |
227 | (*reply) (); | |
28f540f4 RM |
228 | |
229 | machine_get_basic_state (ss->thread, state); | |
230 | } | |
231 | ||
232 | /* Find the location of the MiG reply port cell in use by the thread whose | |
54da5be3 RM |
233 | state is described by THREAD_STATE. If SIGTHREAD is nonzero, make sure |
234 | that this location can be set without faulting, or else return NULL. */ | |
28f540f4 RM |
235 | |
236 | static mach_port_t * | |
54da5be3 RM |
237 | interrupted_reply_port_location (struct machine_thread_all_state *thread_state, |
238 | int sigthread) | |
28f540f4 RM |
239 | { |
240 | mach_port_t *portloc = (mach_port_t *) __hurd_threadvar_location_from_sp | |
241 | (_HURD_THREADVAR_MIG_REPLY, (void *) thread_state->basic.SP); | |
242 | ||
fb8e70d6 RM |
243 | if (sigthread && _hurdsig_catch_memory_fault (portloc)) |
244 | /* Faulted trying to read the stack. */ | |
245 | return NULL; | |
28f540f4 RM |
246 | |
247 | /* Fault now if this pointer is bogus. */ | |
248 | *(volatile mach_port_t *) portloc = *portloc; | |
249 | ||
54da5be3 RM |
250 | if (sigthread) |
251 | _hurdsig_end_catch_fault (); | |
28f540f4 RM |
252 | |
253 | return portloc; | |
254 | } | |
3fe9de0d | 255 | \f |
6df1b247 | 256 | #include <hurd/sigpreempt.h> |
8f480b4b | 257 | #include <intr-msg.h> |
28f540f4 | 258 | |
d3dc731b MB |
259 | /* Timeout on interrupt_operation calls. */ |
260 | mach_msg_timeout_t _hurdsig_interrupt_timeout = 1000; | |
261 | ||
28f540f4 RM |
262 | /* SS->thread is suspended. |
263 | ||
264 | Abort any interruptible RPC operation the thread is doing. | |
265 | ||
266 | This uses only the constant member SS->thread and the unlocked, atomically | |
267 | set member SS->intr_port, so no locking is needed. | |
268 | ||
269 | If successfully sent an interrupt_operation and therefore the thread should | |
270 | wait for its pending RPC to return (possibly EINTR) before taking the | |
271 | incoming signal, returns the reply port to be received on. Otherwise | |
272 | returns MACH_PORT_NULL. | |
273 | ||
75914335 RM |
274 | SIGNO is used to find the applicable SA_RESTART bit. If SIGNO is zero, |
275 | the RPC fails with EINTR instead of restarting (thread_cancel). | |
276 | ||
28f540f4 RM |
277 | *STATE_CHANGE is set nonzero if STATE->basic was modified and should |
278 | be applied back to the thread if it might ever run again, else zero. */ | |
279 | ||
191abc51 | 280 | mach_port_t |
75914335 | 281 | _hurdsig_abort_rpcs (struct hurd_sigstate *ss, int signo, int sigthread, |
54da5be3 | 282 | struct machine_thread_all_state *state, int *state_change, |
1a3a58fd | 283 | void (*reply) (void)) |
28f540f4 | 284 | { |
3fe9de0d | 285 | extern const void _hurd_intr_rpc_msg_in_trap; |
54da5be3 | 286 | mach_port_t rcv_port = MACH_PORT_NULL; |
28f540f4 RM |
287 | mach_port_t intr_port; |
288 | ||
289 | *state_change = 0; | |
290 | ||
291 | intr_port = ss->intr_port; | |
292 | if (intr_port == MACH_PORT_NULL) | |
293 | /* No interruption needs done. */ | |
294 | return MACH_PORT_NULL; | |
295 | ||
296 | /* Abort the thread's kernel context, so any pending message send or | |
297 | receive completes immediately or aborts. */ | |
1a3a58fd | 298 | abort_thread (ss, state, reply); |
28f540f4 | 299 | |
54da5be3 | 300 | if (state->basic.PC < (natural_t) &_hurd_intr_rpc_msg_in_trap) |
28f540f4 | 301 | { |
54da5be3 RM |
302 | /* The thread is about to do the RPC, but hasn't yet entered |
303 | mach_msg. Mutate the thread's state so it knows not to try | |
304 | the RPC. */ | |
3fe9de0d | 305 | INTR_MSG_BACK_OUT (&state->basic); |
54da5be3 RM |
306 | MACHINE_THREAD_STATE_SET_PC (&state->basic, |
307 | &_hurd_intr_rpc_msg_in_trap); | |
308 | state->basic.SYSRETURN = MACH_SEND_INTERRUPTED; | |
309 | *state_change = 1; | |
28f540f4 | 310 | } |
54da5be3 RM |
311 | else if (state->basic.PC == (natural_t) &_hurd_intr_rpc_msg_in_trap && |
312 | /* The thread was blocked in the system call. After thread_abort, | |
313 | the return value register indicates what state the RPC was in | |
314 | when interrupted. */ | |
315 | state->basic.SYSRETURN == MACH_RCV_INTERRUPTED) | |
316 | { | |
317 | /* The RPC request message was sent and the thread was waiting for | |
318 | the reply message; now the message receive has been aborted, so | |
319 | the mach_msg call will return MACH_RCV_INTERRUPTED. We must tell | |
320 | the server to interrupt the pending operation. The thread must | |
321 | wait for the reply message before running the signal handler (to | |
322 | guarantee that the operation has finished being interrupted), so | |
323 | our nonzero return tells the trampoline code to finish the message | |
324 | receive operation before running the handler. */ | |
325 | ||
326 | mach_port_t *reply = interrupted_reply_port_location (state, | |
327 | sigthread); | |
d3dc731b | 328 | error_t err = __interrupt_operation (intr_port, _hurdsig_interrupt_timeout); |
54da5be3 RM |
329 | |
330 | if (err) | |
331 | { | |
332 | if (reply) | |
333 | { | |
334 | /* The interrupt didn't work. | |
335 | Destroy the receive right the thread is blocked on. */ | |
336 | __mach_port_destroy (__mach_task_self (), *reply); | |
337 | *reply = MACH_PORT_NULL; | |
338 | } | |
28f540f4 | 339 | |
54da5be3 RM |
340 | /* The system call return value register now contains |
341 | MACH_RCV_INTERRUPTED; when mach_msg resumes, it will retry the | |
342 | call. Since we have just destroyed the receive right, the | |
343 | retry will fail with MACH_RCV_INVALID_NAME. Instead, just | |
344 | change the return value here to EINTR so mach_msg will not | |
345 | retry and the EINTR error code will propagate up. */ | |
346 | state->basic.SYSRETURN = EINTR; | |
347 | *state_change = 1; | |
348 | } | |
349 | else if (reply) | |
350 | rcv_port = *reply; | |
351 | ||
352 | /* All threads whose RPCs were interrupted by the interrupt_operation | |
353 | call above will retry their RPCs unless we clear SS->intr_port. | |
354 | So we clear it for the thread taking a signal when SA_RESTART is | |
355 | clear, so that its call returns EINTR. */ | |
356 | if (! signo || !(ss->actions[signo].sa_flags & SA_RESTART)) | |
357 | ss->intr_port = MACH_PORT_NULL; | |
358 | } | |
28f540f4 | 359 | |
54da5be3 | 360 | return rcv_port; |
28f540f4 RM |
361 | } |
362 | ||
54da5be3 | 363 | |
28f540f4 RM |
364 | /* Abort the RPCs being run by all threads but this one; |
365 | all other threads should be suspended. If LIVE is nonzero, those | |
366 | threads may run again, so they should be adjusted as necessary to be | |
367 | happy when resumed. STATE is clobbered as a scratch area; its initial | |
368 | contents are ignored, and its contents on return are not useful. */ | |
369 | ||
370 | static void | |
371 | abort_all_rpcs (int signo, struct machine_thread_all_state *state, int live) | |
372 | { | |
373 | /* We can just loop over the sigstates. Any thread doing something | |
374 | interruptible must have one. We needn't bother locking because all | |
375 | other threads are stopped. */ | |
376 | ||
377 | struct hurd_sigstate *ss; | |
378 | size_t nthreads; | |
379 | mach_port_t *reply_ports; | |
380 | ||
381 | /* First loop over the sigstates to count them. | |
382 | We need to know how big a vector we will need for REPLY_PORTS. */ | |
383 | nthreads = 0; | |
384 | for (ss = _hurd_sigstates; ss != NULL; ss = ss->next) | |
385 | ++nthreads; | |
386 | ||
387 | reply_ports = alloca (nthreads * sizeof *reply_ports); | |
388 | ||
389 | nthreads = 0; | |
fb8e70d6 | 390 | for (ss = _hurd_sigstates; ss != NULL; ss = ss->next, ++nthreads) |
28f540f4 | 391 | if (ss->thread == _hurd_msgport_thread) |
fb8e70d6 | 392 | reply_ports[nthreads] = MACH_PORT_NULL; |
28f540f4 RM |
393 | else |
394 | { | |
395 | int state_changed; | |
396 | state->set = 0; /* Reset scratch area. */ | |
397 | ||
398 | /* Abort any operation in progress with interrupt_operation. | |
399 | Record the reply port the thread is waiting on. | |
400 | We will wait for all the replies below. */ | |
fb8e70d6 RM |
401 | reply_ports[nthreads] = _hurdsig_abort_rpcs (ss, signo, 1, |
402 | state, &state_changed, | |
403 | NULL); | |
404 | if (live) | |
405 | { | |
406 | if (reply_ports[nthreads] != MACH_PORT_NULL) | |
407 | { | |
408 | /* We will wait for the reply to this RPC below, so the | |
409 | thread must issue a new RPC rather than waiting for the | |
410 | reply to the one it sent. */ | |
411 | state->basic.SYSRETURN = EINTR; | |
412 | state_changed = 1; | |
413 | } | |
414 | if (state_changed) | |
415 | /* Aborting the RPC needed to change this thread's state, | |
416 | and it might ever run again. So write back its state. */ | |
417 | __thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR, | |
418 | (natural_t *) &state->basic, | |
419 | MACHINE_THREAD_STATE_COUNT); | |
420 | } | |
28f540f4 RM |
421 | } |
422 | ||
423 | /* Wait for replies from all the successfully interrupted RPCs. */ | |
424 | while (nthreads-- > 0) | |
425 | if (reply_ports[nthreads] != MACH_PORT_NULL) | |
426 | { | |
427 | error_t err; | |
428 | mach_msg_header_t head; | |
54da5be3 | 429 | err = __mach_msg (&head, MACH_RCV_MSG|MACH_RCV_TIMEOUT, 0, sizeof head, |
28f540f4 | 430 | reply_ports[nthreads], |
54da5be3 RM |
431 | _hurd_interrupted_rpc_timeout, MACH_PORT_NULL); |
432 | switch (err) | |
433 | { | |
434 | case MACH_RCV_TIMED_OUT: | |
435 | case MACH_RCV_TOO_LARGE: | |
436 | break; | |
437 | ||
438 | default: | |
439 | assert_perror (err); | |
440 | } | |
28f540f4 RM |
441 | } |
442 | } | |
443 | ||
43b0e40f | 444 | struct hurd_signal_preemptor *_hurdsig_preemptors = 0; |
6df1b247 | 445 | sigset_t _hurdsig_preempted_set; |
28f540f4 | 446 | |
6bac11d9 MB |
447 | /* XXX temporary to deal with spelling fix */ |
448 | weak_alias (_hurdsig_preemptors, _hurdsig_preempters) | |
449 | ||
28f540f4 RM |
450 | /* Mask of stop signals. */ |
451 | #define STOPSIGS (sigmask (SIGTTIN) | sigmask (SIGTTOU) | \ | |
452 | sigmask (SIGSTOP) | sigmask (SIGTSTP)) | |
453 | ||
454 | /* Deliver a signal. SS is not locked. */ | |
455 | void | |
456 | _hurd_internal_post_signal (struct hurd_sigstate *ss, | |
93a470c7 | 457 | int signo, struct hurd_signal_detail *detail, |
28f540f4 RM |
458 | mach_port_t reply_port, |
459 | mach_msg_type_name_t reply_port_type, | |
460 | int untraced) | |
461 | { | |
b96bdcd7 | 462 | error_t err; |
28f540f4 RM |
463 | struct machine_thread_all_state thread_state; |
464 | enum { stop, ignore, core, term, handle } act; | |
465 | sighandler_t handler; | |
28f540f4 RM |
466 | sigset_t pending; |
467 | int ss_suspended; | |
468 | ||
469 | /* Reply to this sig_post message. */ | |
1a3a58fd RM |
470 | __typeof (__msg_sig_post_reply) *reply_rpc |
471 | = (untraced ? __msg_sig_post_untraced_reply : __msg_sig_post_reply); | |
472 | void reply (void) | |
28f540f4 | 473 | { |
1a3a58fd RM |
474 | error_t err; |
475 | if (reply_port == MACH_PORT_NULL) | |
476 | return; | |
477 | err = (*reply_rpc) (reply_port, reply_port_type, 0); | |
478 | reply_port = MACH_PORT_NULL; | |
479 | if (err != MACH_SEND_INVALID_DEST) /* Ignore dead reply port. */ | |
480 | assert_perror (err); | |
28f540f4 RM |
481 | } |
482 | ||
483 | /* Mark the signal as pending. */ | |
484 | void mark_pending (void) | |
485 | { | |
486 | __sigaddset (&ss->pending, signo); | |
93a470c7 | 487 | /* Save the details to be given to the handler when SIGNO is |
28f540f4 | 488 | unblocked. */ |
93a470c7 | 489 | ss->pending_data[signo] = *detail; |
28f540f4 RM |
490 | } |
491 | ||
492 | /* Suspend the process with SIGNO. */ | |
493 | void suspend (void) | |
494 | { | |
495 | /* Stop all other threads and mark ourselves stopped. */ | |
496 | __USEPORT (PROC, | |
497 | ({ | |
498 | /* Hold the siglock while stopping other threads to be | |
499 | sure it is not held by another thread afterwards. */ | |
500 | __mutex_lock (&_hurd_siglock); | |
501 | __proc_dostop (port, _hurd_msgport_thread); | |
502 | __mutex_unlock (&_hurd_siglock); | |
503 | abort_all_rpcs (signo, &thread_state, 1); | |
6a7169a5 | 504 | reply (); |
0e3426bb | 505 | __proc_mark_stop (port, signo, detail->code); |
28f540f4 RM |
506 | })); |
507 | _hurd_stopped = 1; | |
508 | } | |
75914335 RM |
509 | /* Resume the process after a suspension. */ |
510 | void resume (void) | |
511 | { | |
512 | /* Resume the process from being stopped. */ | |
513 | thread_t *threads; | |
514 | mach_msg_type_number_t nthreads, i; | |
515 | error_t err; | |
516 | ||
517 | if (! _hurd_stopped) | |
518 | return; | |
519 | ||
520 | /* Tell the proc server we are continuing. */ | |
521 | __USEPORT (PROC, __proc_mark_cont (port)); | |
522 | /* Fetch ports to all our threads and resume them. */ | |
523 | err = __task_threads (__mach_task_self (), &threads, &nthreads); | |
524 | assert_perror (err); | |
525 | for (i = 0; i < nthreads; ++i) | |
526 | { | |
527 | if (threads[i] != _hurd_msgport_thread && | |
528 | (act != handle || threads[i] != ss->thread)) | |
529 | { | |
530 | err = __thread_resume (threads[i]); | |
531 | assert_perror (err); | |
532 | } | |
533 | err = __mach_port_deallocate (__mach_task_self (), | |
534 | threads[i]); | |
535 | assert_perror (err); | |
536 | } | |
537 | __vm_deallocate (__mach_task_self (), | |
538 | (vm_address_t) threads, | |
539 | nthreads * sizeof *threads); | |
540 | _hurd_stopped = 0; | |
4d02a5b1 RM |
541 | if (act == handle) |
542 | /* The thread that will run the handler is already suspended. */ | |
543 | ss_suspended = 1; | |
75914335 RM |
544 | } |
545 | ||
546 | if (signo == 0) | |
547 | { | |
548 | if (untraced) | |
549 | /* This is PTRACE_CONTINUE. */ | |
550 | resume (); | |
551 | ||
552 | /* This call is just to check for pending signals. */ | |
553 | __spin_lock (&ss->lock); | |
554 | goto check_pending_signals; | |
555 | } | |
28f540f4 RM |
556 | |
557 | post_signal: | |
558 | ||
559 | thread_state.set = 0; /* We know nothing. */ | |
560 | ||
6df1b247 | 561 | __spin_lock (&ss->lock); |
28f540f4 | 562 | |
6df1b247 RM |
563 | /* Check for a preempted signal. Preempted signals can arrive during |
564 | critical sections. */ | |
e26996aa RM |
565 | { |
566 | inline sighandler_t try_preemptor (struct hurd_signal_preemptor *pe) | |
567 | { /* PE cannot be null. */ | |
568 | do | |
569 | { | |
570 | if (HURD_PREEMPT_SIGNAL_P (pe, signo, detail->code)) | |
571 | { | |
572 | if (pe->preemptor) | |
573 | { | |
574 | sighandler_t handler = (*pe->preemptor) (pe, ss, | |
575 | &signo, detail); | |
576 | if (handler != SIG_ERR) | |
577 | return handler; | |
578 | } | |
579 | else | |
580 | return pe->handler; | |
581 | } | |
582 | pe = pe->next; | |
583 | } while (pe != 0); | |
584 | return SIG_ERR; | |
585 | } | |
6df1b247 | 586 | |
e26996aa | 587 | handler = ss->preemptors ? try_preemptor (ss->preemptors) : SIG_ERR; |
6df1b247 | 588 | |
e26996aa | 589 | /* If no thread-specific preemptor, check for a global one. */ |
044edf6d | 590 | if (handler == SIG_ERR && __sigismember (&_hurdsig_preempted_set, signo)) |
e26996aa RM |
591 | { |
592 | __mutex_lock (&_hurd_siglock); | |
593 | handler = try_preemptor (_hurdsig_preemptors); | |
594 | __mutex_unlock (&_hurd_siglock); | |
595 | } | |
596 | } | |
28f540f4 RM |
597 | |
598 | ss_suspended = 0; | |
599 | ||
6df1b247 RM |
600 | if (handler == SIG_IGN) |
601 | /* Ignore the signal altogether. */ | |
602 | act = ignore; | |
09d434df | 603 | else if (handler != SIG_ERR) |
28f540f4 RM |
604 | /* Run the preemption-provided handler. */ |
605 | act = handle; | |
606 | else | |
607 | { | |
608 | /* No preemption. Do normal handling. */ | |
609 | ||
8f0c527e | 610 | if (!untraced && __sigismember (&_hurdsig_traced, signo)) |
28f540f4 RM |
611 | { |
612 | /* We are being traced. Stop to tell the debugger of the signal. */ | |
613 | if (_hurd_stopped) | |
614 | /* Already stopped. Mark the signal as pending; | |
615 | when resumed, we will notice it and stop again. */ | |
616 | mark_pending (); | |
617 | else | |
618 | suspend (); | |
619 | __spin_unlock (&ss->lock); | |
620 | reply (); | |
621 | return; | |
622 | } | |
623 | ||
75914335 RM |
624 | handler = ss->actions[signo].sa_handler; |
625 | ||
28f540f4 RM |
626 | if (handler == SIG_DFL) |
627 | /* Figure out the default action for this signal. */ | |
628 | switch (signo) | |
629 | { | |
630 | case 0: | |
631 | /* A sig_post msg with SIGNO==0 is sent to | |
632 | tell us to check for pending signals. */ | |
633 | act = ignore; | |
634 | break; | |
635 | ||
636 | case SIGTTIN: | |
637 | case SIGTTOU: | |
638 | case SIGSTOP: | |
639 | case SIGTSTP: | |
640 | act = stop; | |
641 | break; | |
642 | ||
643 | case SIGCONT: | |
644 | case SIGIO: | |
645 | case SIGURG: | |
646 | case SIGCHLD: | |
647 | case SIGWINCH: | |
648 | act = ignore; | |
649 | break; | |
650 | ||
651 | case SIGQUIT: | |
652 | case SIGILL: | |
653 | case SIGTRAP: | |
654 | case SIGIOT: | |
655 | case SIGEMT: | |
656 | case SIGFPE: | |
657 | case SIGBUS: | |
658 | case SIGSEGV: | |
659 | case SIGSYS: | |
660 | act = core; | |
661 | break; | |
662 | ||
663 | case SIGINFO: | |
664 | if (_hurd_pgrp == _hurd_pid) | |
665 | { | |
666 | /* We are the process group leader. Since there is no | |
667 | user-specified handler for SIGINFO, we use a default one | |
668 | which prints something interesting. We use the normal | |
669 | handler mechanism instead of just doing it here to avoid | |
670 | the signal thread faulting or blocking in this | |
671 | potentially hairy operation. */ | |
672 | act = handle; | |
673 | handler = _hurd_siginfo_handler; | |
674 | } | |
675 | else | |
676 | act = ignore; | |
677 | break; | |
678 | ||
679 | default: | |
680 | act = term; | |
681 | break; | |
682 | } | |
683 | else if (handler == SIG_IGN) | |
684 | act = ignore; | |
685 | else | |
686 | act = handle; | |
687 | ||
688 | if (__sigmask (signo) & STOPSIGS) | |
689 | /* Stop signals clear a pending SIGCONT even if they | |
690 | are handled or ignored (but not if preempted). */ | |
05dea6d1 | 691 | __sigdelset (&ss->pending, SIGCONT); |
28f540f4 RM |
692 | else |
693 | { | |
694 | if (signo == SIGCONT) | |
695 | /* Even if handled or ignored (but not preempted), SIGCONT clears | |
696 | stop signals and resumes the process. */ | |
697 | ss->pending &= ~STOPSIGS; | |
698 | ||
699 | if (_hurd_stopped && act != stop && (untraced || signo == SIGCONT)) | |
75914335 | 700 | resume (); |
28f540f4 RM |
701 | } |
702 | } | |
703 | ||
704 | if (_hurd_orphaned && act == stop && | |
705 | (__sigmask (signo) & (__sigmask (SIGTTIN) | __sigmask (SIGTTOU) | | |
706 | __sigmask (SIGTSTP)))) | |
707 | { | |
708 | /* If we would ordinarily stop for a job control signal, but we are | |
709 | orphaned so noone would ever notice and continue us again, we just | |
710 | quietly die, alone and in the dark. */ | |
0e3426bb | 711 | detail->code = signo; |
28f540f4 RM |
712 | signo = SIGKILL; |
713 | act = term; | |
714 | } | |
715 | ||
75914335 | 716 | /* Handle receipt of a blocked signal, or any signal while stopped. */ |
4d02a5b1 RM |
717 | if (act != ignore && /* Signals ignored now are forgotten now. */ |
718 | __sigismember (&ss->blocked, signo) || | |
28f540f4 RM |
719 | (signo != SIGKILL && _hurd_stopped)) |
720 | { | |
721 | mark_pending (); | |
722 | act = ignore; | |
723 | } | |
724 | ||
725 | /* Perform the chosen action for the signal. */ | |
726 | switch (act) | |
727 | { | |
728 | case stop: | |
729 | if (_hurd_stopped) | |
b96bdcd7 RM |
730 | { |
731 | /* We are already stopped, but receiving an untraced stop | |
732 | signal. Instead of resuming and suspending again, just | |
733 | notify the proc server of the new stop signal. */ | |
0e3426bb RM |
734 | error_t err = __USEPORT (PROC, __proc_mark_stop |
735 | (port, signo, detail->code)); | |
b96bdcd7 RM |
736 | assert_perror (err); |
737 | } | |
28f540f4 RM |
738 | else |
739 | /* Suspend the process. */ | |
740 | suspend (); | |
741 | break; | |
742 | ||
743 | case ignore: | |
2b965f1b RM |
744 | if (detail->exc) |
745 | /* Blocking or ignoring a machine exception is fatal. | |
746 | Otherwise we could just spin on the faulting instruction. */ | |
747 | goto fatal; | |
748 | ||
4d02a5b1 RM |
749 | /* Nobody cares about this signal. If there was a call to resume |
750 | above in SIGCONT processing and we've left a thread suspended, | |
751 | now's the time to set it going. */ | |
752 | if (ss_suspended) | |
753 | { | |
754 | err = __thread_resume (ss->thread); | |
755 | assert_perror (err); | |
756 | ss_suspended = 0; | |
757 | } | |
28f540f4 RM |
758 | break; |
759 | ||
421f82e5 RM |
760 | sigbomb: |
761 | /* We got a fault setting up the stack frame for the handler. | |
762 | Nothing to do but die; BSD gets SIGILL in this case. */ | |
0e3426bb | 763 | detail->code = signo; /* XXX ? */ |
421f82e5 | 764 | signo = SIGILL; |
2b965f1b RM |
765 | |
766 | fatal: | |
421f82e5 RM |
767 | act = core; |
768 | /* FALLTHROUGH */ | |
769 | ||
28f540f4 RM |
770 | case term: /* Time to die. */ |
771 | case core: /* And leave a rotting corpse. */ | |
28f540f4 | 772 | /* Have the proc server stop all other threads in our task. */ |
b96bdcd7 RM |
773 | err = __USEPORT (PROC, __proc_dostop (port, _hurd_msgport_thread)); |
774 | assert_perror (err); | |
28f540f4 RM |
775 | /* No more user instructions will be executed. |
776 | The signal can now be considered delivered. */ | |
777 | reply (); | |
778 | /* Abort all server operations now in progress. */ | |
779 | abort_all_rpcs (signo, &thread_state, 0); | |
780 | ||
781 | { | |
782 | int status = W_EXITCODE (0, signo); | |
783 | /* Do a core dump if desired. Only set the wait status bit saying we | |
784 | in fact dumped core if the operation was actually successful. */ | |
0e3426bb | 785 | if (act == core && write_corefile (signo, detail)) |
28f540f4 RM |
786 | status |= WCOREFLAG; |
787 | /* Tell proc how we died and then stick the saber in the gut. */ | |
788 | _hurd_exit (status); | |
789 | /* NOTREACHED */ | |
790 | } | |
791 | ||
792 | case handle: | |
793 | /* Call a handler for this signal. */ | |
794 | { | |
421f82e5 | 795 | struct sigcontext *scp, ocontext; |
28f540f4 RM |
796 | int wait_for_reply, state_changed; |
797 | ||
798 | /* Stop the thread and abort its pending RPC operations. */ | |
799 | if (! ss_suspended) | |
b96bdcd7 RM |
800 | { |
801 | err = __thread_suspend (ss->thread); | |
802 | assert_perror (err); | |
803 | } | |
28f540f4 RM |
804 | |
805 | /* Abort the thread's kernel context, so any pending message send | |
806 | or receive completes immediately or aborts. If an interruptible | |
807 | RPC is in progress, abort_rpcs will do this. But we must always | |
808 | do it before fetching the thread's state, because | |
809 | thread_get_state is never kosher before thread_abort. */ | |
1a3a58fd | 810 | abort_thread (ss, &thread_state, NULL); |
28f540f4 | 811 | |
421f82e5 RM |
812 | if (ss->context) |
813 | { | |
814 | /* We have a previous sigcontext that sigreturn was about | |
815 | to restore when another signal arrived. */ | |
816 | ||
817 | mach_port_t *loc; | |
28f540f4 | 818 | |
fb8e70d6 | 819 | if (_hurdsig_catch_memory_fault (ss->context)) |
421f82e5 | 820 | { |
421f82e5 RM |
821 | /* We faulted reading the thread's stack. Forget that |
822 | context and pretend it wasn't there. It almost | |
823 | certainly crash if this handler returns, but that's it's | |
824 | problem. */ | |
825 | ss->context = NULL; | |
826 | } | |
827 | else | |
828 | { | |
829 | /* Copy the context from the thread's stack before | |
830 | we start diddling the stack to set up the handler. */ | |
831 | ocontext = *ss->context; | |
832 | ss->context = &ocontext; | |
833 | } | |
834 | _hurdsig_end_catch_fault (); | |
75914335 | 835 | |
421f82e5 RM |
836 | if (! machine_get_basic_state (ss->thread, &thread_state)) |
837 | goto sigbomb; | |
54da5be3 | 838 | loc = interrupted_reply_port_location (&thread_state, 1); |
421f82e5 RM |
839 | if (loc && *loc != MACH_PORT_NULL) |
840 | /* This is the reply port for the context which called | |
841 | sigreturn. Since we are abandoning that context entirely | |
842 | and restoring SS->context instead, destroy this port. */ | |
843 | __mach_port_destroy (__mach_task_self (), *loc); | |
844 | ||
845 | /* The thread was in sigreturn, not in any interruptible RPC. */ | |
846 | wait_for_reply = 0; | |
847 | ||
8f0c527e | 848 | assert (! __spin_lock_locked (&ss->critical_section_lock)); |
421f82e5 RM |
849 | } |
850 | else | |
28f540f4 | 851 | { |
e33b438a RM |
852 | int crit = __spin_lock_locked (&ss->critical_section_lock); |
853 | ||
54da5be3 | 854 | wait_for_reply |
e33b438a RM |
855 | = (_hurdsig_abort_rpcs (ss, |
856 | /* In a critical section, any RPC | |
857 | should be cancelled instead of | |
858 | restarted, regardless of | |
3081378b | 859 | SA_RESTART, so the entire |
e33b438a RM |
860 | "atomic" operation can be aborted |
861 | as a unit. */ | |
862 | crit ? 0 : signo, 1, | |
54da5be3 | 863 | &thread_state, &state_changed, |
1a3a58fd | 864 | &reply) |
54da5be3 | 865 | != MACH_PORT_NULL); |
421f82e5 | 866 | |
e33b438a | 867 | if (crit) |
421f82e5 RM |
868 | { |
869 | /* The thread is in a critical section. Mark the signal as | |
870 | pending. When it finishes the critical section, it will | |
871 | check for pending signals. */ | |
872 | mark_pending (); | |
e33b438a RM |
873 | if (state_changed) |
874 | /* Some cases of interrupting an RPC must change the | |
875 | thread state to back out the call. Normally this | |
876 | change is rolled into the warping to the handler and | |
877 | sigreturn, but we are not running the handler now | |
878 | because the thread is in a critical section. Instead, | |
879 | mutate the thread right away for the RPC interruption | |
880 | and resume it; the RPC will return early so the | |
881 | critical section can end soon. */ | |
882 | __thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR, | |
883 | (natural_t *) &thread_state.basic, | |
884 | MACHINE_THREAD_STATE_COUNT); | |
885 | /* */ | |
886 | ss->intr_port = MACH_PORT_NULL; | |
421f82e5 RM |
887 | __thread_resume (ss->thread); |
888 | break; | |
889 | } | |
28f540f4 RM |
890 | } |
891 | ||
892 | /* Call the machine-dependent function to set the thread up | |
893 | to run the signal handler, and preserve its old context. */ | |
0e3426bb | 894 | scp = _hurd_setup_sighandler (ss, handler, signo, detail, |
28f540f4 RM |
895 | wait_for_reply, &thread_state); |
896 | if (scp == NULL) | |
421f82e5 | 897 | goto sigbomb; |
28f540f4 RM |
898 | |
899 | /* Set the machine-independent parts of the signal context. */ | |
900 | ||
28f540f4 RM |
901 | { |
902 | /* Fetch the thread variable for the MiG reply port, | |
903 | and set it to MACH_PORT_NULL. */ | |
54da5be3 RM |
904 | mach_port_t *loc = interrupted_reply_port_location (&thread_state, |
905 | 1); | |
28f540f4 RM |
906 | if (loc) |
907 | { | |
908 | scp->sc_reply_port = *loc; | |
909 | *loc = MACH_PORT_NULL; | |
910 | } | |
911 | else | |
912 | scp->sc_reply_port = MACH_PORT_NULL; | |
421f82e5 RM |
913 | |
914 | /* Save the intr_port in use by the interrupted code, | |
915 | and clear the cell before running the trampoline. */ | |
916 | scp->sc_intr_port = ss->intr_port; | |
917 | ss->intr_port = MACH_PORT_NULL; | |
918 | ||
919 | if (ss->context) | |
920 | { | |
921 | /* After the handler runs we will restore to the state in | |
922 | SS->context, not the state of the thread now. So restore | |
923 | that context's reply port and intr port. */ | |
924 | ||
925 | scp->sc_reply_port = ss->context->sc_reply_port; | |
926 | scp->sc_intr_port = ss->context->sc_intr_port; | |
927 | ||
928 | ss->context = NULL; | |
929 | } | |
28f540f4 RM |
930 | } |
931 | ||
421f82e5 | 932 | /* Backdoor extra argument to signal handler. */ |
0e3426bb | 933 | scp->sc_error = detail->error; |
421f82e5 | 934 | |
ac61ed31 | 935 | /* Block requested signals while running the handler. */ |
28f540f4 | 936 | scp->sc_mask = ss->blocked; |
05dea6d1 | 937 | __sigorset (&ss->blocked, &ss->blocked, &ss->actions[signo].sa_mask); |
5d83494f | 938 | |
ac61ed31 MK |
939 | /* Also block SIGNO unless we're asked not to. */ |
940 | if (! (ss->actions[signo].sa_flags & (SA_RESETHAND | SA_NODEFER))) | |
05dea6d1 | 941 | __sigaddset (&ss->blocked, signo); |
5d83494f | 942 | |
ac61ed31 MK |
943 | /* Reset to SIG_DFL if requested. SIGILL and SIGTRAP cannot |
944 | be automatically reset when delivered; the system silently | |
945 | enforces this restriction. */ | |
946 | if (ss->actions[signo].sa_flags & SA_RESETHAND | |
947 | && signo != SIGILL && signo != SIGTRAP) | |
5d83494f | 948 | ss->actions[signo].sa_handler = SIG_DFL; |
28f540f4 | 949 | |
28f540f4 RM |
950 | /* Start the thread running the handler (or possibly waiting for an |
951 | RPC reply before running the handler). */ | |
b96bdcd7 RM |
952 | err = __thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR, |
953 | (natural_t *) &thread_state.basic, | |
954 | MACHINE_THREAD_STATE_COUNT); | |
955 | assert_perror (err); | |
956 | err = __thread_resume (ss->thread); | |
957 | assert_perror (err); | |
28f540f4 RM |
958 | thread_state.set = 0; /* Everything we know is now wrong. */ |
959 | break; | |
960 | } | |
961 | } | |
962 | ||
963 | /* The signal has either been ignored or is now being handled. We can | |
75914335 RM |
964 | consider it delivered and reply to the killer. */ |
965 | reply (); | |
28f540f4 RM |
966 | |
967 | /* We get here unless the signal was fatal. We still hold SS->lock. | |
968 | Check for pending signals, and loop to post them. */ | |
7cc645ed RM |
969 | { |
970 | /* Return nonzero if SS has any signals pending we should worry about. | |
971 | We don't worry about any pending signals if we are stopped, nor if | |
972 | SS is in a critical section. We are guaranteed to get a sig_post | |
973 | message before any of them become deliverable: either the SIGCONT | |
974 | signal, or a sig_post with SIGNO==0 as an explicit poll when the | |
975 | thread finishes its critical section. */ | |
976 | inline int signals_pending (void) | |
977 | { | |
8f0c527e | 978 | if (_hurd_stopped || __spin_lock_locked (&ss->critical_section_lock)) |
7cc645ed RM |
979 | return 0; |
980 | return pending = ss->pending & ~ss->blocked; | |
981 | } | |
982 | ||
75914335 RM |
983 | check_pending_signals: |
984 | untraced = 0; | |
985 | ||
7cc645ed RM |
986 | if (signals_pending ()) |
987 | { | |
7cc645ed RM |
988 | for (signo = 1; signo < NSIG; ++signo) |
989 | if (__sigismember (&pending, signo)) | |
990 | { | |
6172aaa3 | 991 | deliver_pending: |
7cc645ed | 992 | __sigdelset (&ss->pending, signo); |
0e3426bb | 993 | *detail = ss->pending_data[signo]; |
7cc645ed RM |
994 | __spin_unlock (&ss->lock); |
995 | goto post_signal; | |
996 | } | |
997 | } | |
998 | ||
999 | /* No pending signals left undelivered for this thread. | |
1000 | If we were sent signal 0, we need to check for pending | |
1001 | signals for all threads. */ | |
1002 | if (signo == 0) | |
1003 | { | |
1004 | __spin_unlock (&ss->lock); | |
1005 | __mutex_lock (&_hurd_siglock); | |
1006 | for (ss = _hurd_sigstates; ss != NULL; ss = ss->next) | |
28f540f4 | 1007 | { |
7cc645ed | 1008 | __spin_lock (&ss->lock); |
4d02a5b1 | 1009 | for (signo = 1; signo < NSIG; ++signo) |
1a6a8198 TBB |
1010 | if (__sigismember (&ss->pending, signo) |
1011 | && (!__sigismember (&ss->blocked, signo) | |
4bbb963e RM |
1012 | /* We "deliver" immediately pending blocked signals whose |
1013 | action might be to ignore, so that if ignored they are | |
1014 | dropped right away. */ | |
1a6a8198 TBB |
1015 | || ss->actions[signo].sa_handler == SIG_IGN |
1016 | || ss->actions[signo].sa_handler == SIG_DFL)) | |
6a60a937 TBB |
1017 | { |
1018 | mutex_unlock (&_hurd_siglock); | |
1019 | goto deliver_pending; | |
1020 | } | |
28f540f4 | 1021 | __spin_unlock (&ss->lock); |
28f540f4 | 1022 | } |
7cc645ed RM |
1023 | __mutex_unlock (&_hurd_siglock); |
1024 | } | |
1025 | else | |
1026 | { | |
1027 | /* No more signals pending; SS->lock is still locked. | |
1028 | Wake up any sigsuspend call that is blocking SS->thread. */ | |
1029 | if (ss->suspended != MACH_PORT_NULL) | |
1030 | { | |
1031 | /* There is a sigsuspend waiting. Tell it to wake up. */ | |
1032 | error_t err; | |
1033 | mach_msg_header_t msg; | |
90f9eba7 | 1034 | msg.msgh_bits = MACH_MSGH_BITS (MACH_MSG_TYPE_MAKE_SEND, 0); |
7cc645ed RM |
1035 | msg.msgh_remote_port = ss->suspended; |
1036 | msg.msgh_local_port = MACH_PORT_NULL; | |
1037 | /* These values do not matter. */ | |
1038 | msg.msgh_id = 8675309; /* Jenny, Jenny. */ | |
7cc645ed RM |
1039 | ss->suspended = MACH_PORT_NULL; |
1040 | err = __mach_msg (&msg, MACH_SEND_MSG, sizeof msg, 0, | |
1041 | MACH_PORT_NULL, MACH_MSG_TIMEOUT_NONE, | |
1042 | MACH_PORT_NULL); | |
1043 | assert_perror (err); | |
1044 | } | |
1045 | __spin_unlock (&ss->lock); | |
1046 | } | |
1047 | } | |
28f540f4 RM |
1048 | |
1049 | /* All pending signals delivered to all threads. | |
1050 | Now we can send the reply message even for signal 0. */ | |
1051 | reply (); | |
1052 | } | |
1053 | \f | |
1054 | /* Decide whether REFPORT enables the sender to send us a SIGNO signal. | |
1055 | Returns zero if so, otherwise the error code to return to the sender. */ | |
1056 | ||
1057 | static error_t | |
1058 | signal_allowed (int signo, mach_port_t refport) | |
1059 | { | |
1060 | if (signo < 0 || signo >= NSIG) | |
1061 | return EINVAL; | |
1062 | ||
1063 | if (refport == __mach_task_self ()) | |
1064 | /* Can send any signal. */ | |
1065 | goto win; | |
1066 | ||
1067 | /* Avoid needing to check for this below. */ | |
1068 | if (refport == MACH_PORT_NULL) | |
1069 | return EPERM; | |
1070 | ||
1071 | switch (signo) | |
1072 | { | |
1073 | case SIGINT: | |
1074 | case SIGQUIT: | |
1075 | case SIGTSTP: | |
1076 | case SIGHUP: | |
1077 | case SIGINFO: | |
1078 | case SIGTTIN: | |
1079 | case SIGTTOU: | |
ce7f605b | 1080 | case SIGWINCH: |
28f540f4 RM |
1081 | /* Job control signals can be sent by the controlling terminal. */ |
1082 | if (__USEPORT (CTTYID, port == refport)) | |
1083 | goto win; | |
1084 | break; | |
1085 | ||
1086 | case SIGCONT: | |
1087 | { | |
1088 | /* A continue signal can be sent by anyone in the session. */ | |
1089 | mach_port_t sessport; | |
1090 | if (! __USEPORT (PROC, __proc_getsidport (port, &sessport))) | |
75914335 | 1091 | { |
28f540f4 RM |
1092 | __mach_port_deallocate (__mach_task_self (), sessport); |
1093 | if (refport == sessport) | |
1094 | goto win; | |
1095 | } | |
1096 | } | |
1097 | break; | |
1098 | ||
1099 | case SIGIO: | |
1100 | case SIGURG: | |
1101 | { | |
1102 | /* Any io object a file descriptor refers to might send us | |
1103 | one of these signals using its async ID port for REFPORT. | |
1104 | ||
1105 | This is pretty wide open; it is not unlikely that some random | |
1106 | process can at least open for reading something we have open, | |
1107 | get its async ID port, and send us a spurious SIGIO or SIGURG | |
1108 | signal. But BSD is actually wider open than that!--you can set | |
1109 | the owner of an io object to any process or process group | |
1110 | whatsoever and send them gratuitous signals. | |
1111 | ||
1112 | Someday we could implement some reasonable scheme for | |
1113 | authorizing SIGIO and SIGURG signals properly. */ | |
1114 | ||
1115 | int d; | |
e0637da1 | 1116 | int lucky = 0; /* True if we find a match for REFPORT. */ |
28f540f4 | 1117 | __mutex_lock (&_hurd_dtable_lock); |
e0637da1 | 1118 | for (d = 0; !lucky && (unsigned) d < (unsigned) _hurd_dtablesize; ++d) |
28f540f4 RM |
1119 | { |
1120 | struct hurd_userlink ulink; | |
1121 | io_t port; | |
1122 | mach_port_t asyncid; | |
1123 | if (_hurd_dtable[d] == NULL) | |
1124 | continue; | |
1125 | port = _hurd_port_get (&_hurd_dtable[d]->port, &ulink); | |
1126 | if (! __io_get_icky_async_id (port, &asyncid)) | |
1127 | { | |
1128 | if (refport == asyncid) | |
1129 | /* Break out of the loop on the next iteration. */ | |
e0637da1 | 1130 | lucky = 1; |
28f540f4 RM |
1131 | __mach_port_deallocate (__mach_task_self (), asyncid); |
1132 | } | |
1133 | _hurd_port_free (&_hurd_dtable[d]->port, &ulink, port); | |
1134 | } | |
c90c1e1c | 1135 | __mutex_unlock (&_hurd_dtable_lock); |
28f540f4 | 1136 | /* If we found a lucky winner, we've set D to -1 in the loop. */ |
e0637da1 | 1137 | if (lucky) |
28f540f4 RM |
1138 | goto win; |
1139 | } | |
1140 | } | |
1141 | ||
1142 | /* If this signal is legit, we have done `goto win' by now. | |
1143 | When we return the error, mig deallocates REFPORT. */ | |
1144 | return EPERM; | |
1145 | ||
1146 | win: | |
1147 | /* Deallocate the REFPORT send right; we are done with it. */ | |
1148 | __mach_port_deallocate (__mach_task_self (), refport); | |
1149 | ||
1150 | return 0; | |
1151 | } | |
1152 | ||
1153 | /* Implement the sig_post RPC from <hurd/msg.defs>; | |
1154 | sent when someone wants us to get a signal. */ | |
1155 | kern_return_t | |
1156 | _S_msg_sig_post (mach_port_t me, | |
1157 | mach_port_t reply_port, mach_msg_type_name_t reply_port_type, | |
8f0c527e | 1158 | int signo, natural_t sigcode, |
28f540f4 RM |
1159 | mach_port_t refport) |
1160 | { | |
1161 | error_t err; | |
93a470c7 | 1162 | struct hurd_signal_detail d; |
28f540f4 RM |
1163 | |
1164 | if (err = signal_allowed (signo, refport)) | |
1165 | return err; | |
1166 | ||
93a470c7 RM |
1167 | d.code = sigcode; |
1168 | d.exc = 0; | |
1169 | ||
28f540f4 RM |
1170 | /* Post the signal to the designated signal-receiving thread. This will |
1171 | reply when the signal can be considered delivered. */ | |
1172 | _hurd_internal_post_signal (_hurd_thread_sigstate (_hurd_sigthread), | |
93a470c7 | 1173 | signo, &d, reply_port, reply_port_type, |
28f540f4 RM |
1174 | 0); /* Stop if traced. */ |
1175 | ||
1176 | return MIG_NO_REPLY; /* Already replied. */ | |
1177 | } | |
1178 | ||
1179 | /* Implement the sig_post_untraced RPC from <hurd/msg.defs>; | |
1180 | sent when the debugger wants us to really get a signal | |
1181 | even if we are traced. */ | |
1182 | kern_return_t | |
1183 | _S_msg_sig_post_untraced (mach_port_t me, | |
1184 | mach_port_t reply_port, | |
1185 | mach_msg_type_name_t reply_port_type, | |
8f0c527e | 1186 | int signo, natural_t sigcode, |
28f540f4 RM |
1187 | mach_port_t refport) |
1188 | { | |
1189 | error_t err; | |
93a470c7 | 1190 | struct hurd_signal_detail d; |
28f540f4 RM |
1191 | |
1192 | if (err = signal_allowed (signo, refport)) | |
1193 | return err; | |
1194 | ||
93a470c7 RM |
1195 | d.code = sigcode; |
1196 | d.exc = 0; | |
1197 | ||
28f540f4 RM |
1198 | /* Post the signal to the designated signal-receiving thread. This will |
1199 | reply when the signal can be considered delivered. */ | |
1200 | _hurd_internal_post_signal (_hurd_thread_sigstate (_hurd_sigthread), | |
93a470c7 | 1201 | signo, &d, reply_port, reply_port_type, |
28f540f4 RM |
1202 | 1); /* Untraced flag. */ |
1203 | ||
1204 | return MIG_NO_REPLY; /* Already replied. */ | |
1205 | } | |
1206 | \f | |
1207 | extern void __mig_init (void *); | |
1208 | ||
1209 | #include <mach/task_special_ports.h> | |
1210 | ||
1211 | /* Initialize the message port and _hurd_sigthread and start the signal | |
1212 | thread. */ | |
1213 | ||
1214 | void | |
62495816 | 1215 | _hurdsig_init (const int *intarray, size_t intarraysize) |
28f540f4 RM |
1216 | { |
1217 | error_t err; | |
1218 | vm_size_t stacksize; | |
62495816 | 1219 | struct hurd_sigstate *ss; |
28f540f4 RM |
1220 | |
1221 | __mutex_init (&_hurd_siglock); | |
1222 | ||
a5a81fec RM |
1223 | err = __mach_port_allocate (__mach_task_self (), |
1224 | MACH_PORT_RIGHT_RECEIVE, | |
1225 | &_hurd_msgport); | |
1226 | assert_perror (err); | |
75914335 | 1227 | |
28f540f4 | 1228 | /* Make a send right to the signal port. */ |
a5a81fec RM |
1229 | err = __mach_port_insert_right (__mach_task_self (), |
1230 | _hurd_msgport, | |
1231 | _hurd_msgport, | |
1232 | MACH_MSG_TYPE_MAKE_SEND); | |
1233 | assert_perror (err); | |
28f540f4 | 1234 | |
62495816 RM |
1235 | /* Initialize the main thread's signal state. */ |
1236 | ss = _hurd_self_sigstate (); | |
1237 | ||
1238 | /* Copy inherited values from our parent (or pre-exec process state) | |
1239 | into the signal settings of the main thread. */ | |
1240 | if (intarraysize > INIT_SIGMASK) | |
1241 | ss->blocked = intarray[INIT_SIGMASK]; | |
1242 | if (intarraysize > INIT_SIGPENDING) | |
760b7056 | 1243 | ss->pending = intarray[INIT_SIGPENDING]; |
62495816 RM |
1244 | if (intarraysize > INIT_SIGIGN && intarray[INIT_SIGIGN] != 0) |
1245 | { | |
1246 | int signo; | |
1247 | for (signo = 1; signo < NSIG; ++signo) | |
1248 | if (intarray[INIT_SIGIGN] & __sigmask(signo)) | |
1249 | ss->actions[signo].sa_handler = SIG_IGN; | |
1250 | } | |
1251 | ||
28f540f4 RM |
1252 | /* Set the default thread to receive task-global signals |
1253 | to this one, the main (first) user thread. */ | |
62495816 | 1254 | _hurd_sigthread = ss->thread; |
28f540f4 RM |
1255 | |
1256 | /* Start the signal thread listening on the message port. */ | |
1257 | ||
72e1a750 RM |
1258 | if (__hurd_threadvar_stack_mask == 0) |
1259 | { | |
1260 | err = __thread_create (__mach_task_self (), &_hurd_msgport_thread); | |
1261 | assert_perror (err); | |
28f540f4 | 1262 | |
72e1a750 RM |
1263 | stacksize = __vm_page_size * 8; /* Small stack for signal thread. */ |
1264 | err = __mach_setup_thread (__mach_task_self (), _hurd_msgport_thread, | |
1265 | _hurd_msgport_receive, | |
1266 | (vm_address_t *) &__hurd_sigthread_stack_base, | |
1267 | &stacksize); | |
1268 | assert_perror (err); | |
28f540f4 | 1269 | |
72e1a750 RM |
1270 | __hurd_sigthread_stack_end = __hurd_sigthread_stack_base + stacksize; |
1271 | __hurd_sigthread_variables = | |
1272 | malloc (__hurd_threadvar_max * sizeof (unsigned long int)); | |
1273 | if (__hurd_sigthread_variables == NULL) | |
1274 | __libc_fatal ("hurd: Can't allocate threadvars for signal thread\n"); | |
cc13edc8 RM |
1275 | memset (__hurd_sigthread_variables, 0, |
1276 | __hurd_threadvar_max * sizeof (unsigned long int)); | |
1277 | __hurd_sigthread_variables[_HURD_THREADVAR_LOCALE] | |
1278 | = (unsigned long int) &_nl_global_locale; | |
28f540f4 | 1279 | |
72e1a750 RM |
1280 | /* Reinitialize the MiG support routines so they will use a per-thread |
1281 | variable for the cached reply port. */ | |
1282 | __mig_init ((void *) __hurd_sigthread_stack_base); | |
28f540f4 | 1283 | |
72e1a750 RM |
1284 | err = __thread_resume (_hurd_msgport_thread); |
1285 | assert_perror (err); | |
1286 | } | |
1287 | else | |
1288 | { | |
1289 | /* When cthreads is being used, we need to make the signal thread a | |
1290 | proper cthread. Otherwise it cannot use mutex_lock et al, which | |
1291 | will be the cthreads versions. Various of the message port RPC | |
1292 | handlers need to take locks, so we need to be able to call into | |
1293 | cthreads code and meet its assumptions about how our thread and | |
1294 | its stack are arranged. Since cthreads puts it there anyway, | |
1295 | we'll let the signal thread's per-thread variables be found as for | |
1296 | any normal cthread, and just leave the magic __hurd_sigthread_* | |
1297 | values all zero so they'll be ignored. */ | |
1298 | #pragma weak cthread_fork | |
1299 | #pragma weak cthread_detach | |
1300 | cthread_detach (cthread_fork ((cthread_fn_t) &_hurd_msgport_receive, 0)); | |
64659255 MK |
1301 | |
1302 | /* XXX We need the thread port for the signal thread further on | |
1303 | in this thread (see hurdfault.c:_hurdsigfault_init). | |
1304 | Therefore we block until _hurd_msgport_thread is initialized | |
1305 | by the newly created thread. This really shouldn't be | |
1306 | necessary; we should be able to fetch the thread port for a | |
1307 | cthread from here. */ | |
1308 | while (_hurd_msgport_thread == 0) | |
1309 | __swtch_pri (0); | |
72e1a750 | 1310 | } |
75914335 | 1311 | |
28f540f4 | 1312 | /* Receive exceptions on the signal port. */ |
7595ddb8 | 1313 | #ifdef TASK_EXCEPTION_PORT |
28f540f4 RM |
1314 | __task_set_special_port (__mach_task_self (), |
1315 | TASK_EXCEPTION_PORT, _hurd_msgport); | |
7595ddb8 RM |
1316 | #elif defined (EXC_MASK_ALL) |
1317 | __task_set_exception_ports (__mach_task_self (), | |
1318 | EXC_MASK_ALL & ~(EXC_MASK_SYSCALL | |
1319 | | EXC_MASK_MACH_SYSCALL | |
1320 | | EXC_MASK_RPC_ALERT), | |
1321 | _hurd_msgport, | |
1322 | EXCEPTION_DEFAULT, MACHINE_THREAD_STATE); | |
1323 | #else | |
1324 | # error task_set_exception_port? | |
1325 | #endif | |
159d4836 RM |
1326 | |
1327 | /* Sanity check. Any pending, unblocked signals should have been | |
1328 | taken by our predecessor incarnation (i.e. parent or pre-exec state) | |
1329 | before packing up our init ints. This assert is last (not above) | |
1330 | so that signal handling is all set up to handle the abort. */ | |
1331 | assert ((ss->pending &~ ss->blocked) == 0); | |
28f540f4 RM |
1332 | } |
1333 | \f /* XXXX */ | |
1334 | /* Reauthenticate with the proc server. */ | |
1335 | ||
1336 | static void | |
1337 | reauth_proc (mach_port_t new) | |
1338 | { | |
1339 | mach_port_t ref, ignore; | |
1340 | ||
1341 | ref = __mach_reply_port (); | |
1342 | if (! HURD_PORT_USE (&_hurd_ports[INIT_PORT_PROC], | |
1343 | __proc_reauthenticate (port, ref, | |
1344 | MACH_MSG_TYPE_MAKE_SEND) || | |
8f0c527e | 1345 | __auth_user_authenticate (new, ref, |
28f540f4 RM |
1346 | MACH_MSG_TYPE_MAKE_SEND, |
1347 | &ignore)) | |
1348 | && ignore != MACH_PORT_NULL) | |
1349 | __mach_port_deallocate (__mach_task_self (), ignore); | |
1350 | __mach_port_destroy (__mach_task_self (), ref); | |
1351 | ||
762a2918 UD |
1352 | /* Set the owner of the process here too. */ |
1353 | mutex_lock (&_hurd_id.lock); | |
1354 | if (!_hurd_check_ids ()) | |
1355 | HURD_PORT_USE (&_hurd_ports[INIT_PORT_PROC], | |
1356 | __proc_setowner (port, | |
1357 | (_hurd_id.gen.nuids | |
1358 | ? _hurd_id.gen.uids[0] : 0), | |
1359 | !_hurd_id.gen.nuids)); | |
1360 | mutex_unlock (&_hurd_id.lock); | |
1361 | ||
28f540f4 RM |
1362 | (void) &reauth_proc; /* Silence compiler warning. */ |
1363 | } | |
1364 | text_set_element (_hurd_reauth_hook, reauth_proc); | |
1365 | \f | |
1366 | /* Like `getenv', but safe for the signal thread to run. | |
1367 | If the environment is trashed, this will just return NULL. */ | |
1368 | ||
1369 | const char * | |
1370 | _hurdsig_getenv (const char *variable) | |
1371 | { | |
a753ffb2 RM |
1372 | if (__libc_enable_secure) |
1373 | return NULL; | |
1374 | ||
fb8e70d6 | 1375 | if (_hurdsig_catch_memory_fault (__environ)) |
28f540f4 RM |
1376 | /* We bombed in getenv. */ |
1377 | return NULL; | |
1378 | else | |
1379 | { | |
fb8e70d6 RM |
1380 | const size_t len = strlen (variable); |
1381 | char *value = NULL; | |
1382 | char *volatile *ep = __environ; | |
1383 | while (*ep) | |
1384 | { | |
1385 | const char *p = *ep; | |
10dc2a90 UD |
1386 | _hurdsig_fault_preemptor.first = (long int) p; |
1387 | _hurdsig_fault_preemptor.last = VM_MAX_ADDRESS; | |
fb8e70d6 RM |
1388 | if (! strncmp (p, variable, len) && p[len] == '=') |
1389 | { | |
fb8e70d6 RM |
1390 | size_t valuelen; |
1391 | p += len + 1; | |
1392 | valuelen = strlen (p); | |
10dc2a90 | 1393 | _hurdsig_fault_preemptor.last = (long int) (p + valuelen); |
fb8e70d6 RM |
1394 | value = malloc (++valuelen); |
1395 | if (value) | |
1396 | memcpy (value, p, valuelen); | |
1397 | break; | |
1398 | } | |
10dc2a90 UD |
1399 | _hurdsig_fault_preemptor.first = (long int) ++ep; |
1400 | _hurdsig_fault_preemptor.last = (long int) (ep + 1); | |
fb8e70d6 | 1401 | } |
28f540f4 RM |
1402 | _hurdsig_end_catch_fault (); |
1403 | return value; | |
1404 | } | |
1405 | } |