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d4f3574e SS |
1 | /* Low level interface for debugging GNU/Linux threads for GDB, |
2 | the GNU debugger. | |
b6ba6518 | 3 | Copyright 1998, 1999, 2000 Free Software Foundation, Inc. |
d4f3574e SS |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ | |
20 | ||
21 | /* This module implements the debugging interface of the linuxthreads package | |
22 | of the glibc. This package implements a simple clone()-based implementation | |
23 | of Posix threads for Linux. To use this module, be sure that you have at | |
24 | least the version of the linuxthreads package that holds the support of | |
25 | GDB (currently 0.8 included in the glibc-2.0.7). | |
26 | ||
27 | Right now, the linuxthreads package does not care of priority scheduling, | |
28 | so, neither this module does; In particular, the threads are resumed | |
29 | in any order, which could lead to different scheduling than the one | |
30 | happening when GDB does not control the execution. | |
31 | ||
32 | The latest point is that ptrace(PT_ATTACH, ...) is intrusive in Linux: | |
33 | When a process is attached, then the attaching process becomes the current | |
34 | parent of the attached process, and the old parent has lost this child. | |
35 | If the old parent does a wait[...](), then this child is no longer | |
36 | considered by the kernel as a child of the old parent, thus leading to | |
37 | results of the call different when the child is attached and when it's not. | |
38 | ||
39 | A fix has been submitted to the Linux community to solve this problem, | |
40 | which consequences are not visible to the application itself, but on the | |
41 | process which may wait() for the completion of the application (mostly, | |
42 | it may consider that the application no longer exists (errno == ECHILD), | |
43 | although it does, and thus being unable to get the exit status and resource | |
44 | usage of the child. If by chance, it is able to wait() for the application | |
45 | after it has died (by receiving first a SIGCHILD, and then doing a wait(), | |
46 | then the exit status and resource usage may be wrong, because the | |
47 | linuxthreads package heavily relies on wait() synchronization to keep | |
48 | them correct. */ | |
49 | ||
203051af | 50 | #include "defs.h" |
d4f3574e SS |
51 | #include <sys/types.h> /* for pid_t */ |
52 | #include <sys/ptrace.h> /* for PT_* flags */ | |
03f2053f | 53 | #include "gdb_wait.h" /* for WUNTRACED and __WCLONE flags */ |
d4f3574e SS |
54 | #include <signal.h> /* for struct sigaction and NSIG */ |
55 | #include <sys/utsname.h> | |
56 | ||
d4f3574e SS |
57 | #include "target.h" |
58 | #include "inferior.h" | |
59 | #include "gdbcore.h" | |
60 | #include "gdbthread.h" | |
d4f3574e SS |
61 | #include "gdbcmd.h" |
62 | #include "breakpoint.h" | |
63 | ||
64 | #ifndef PT_ATTACH | |
65 | #define PT_ATTACH PTRACE_ATTACH | |
66 | #endif | |
67 | #ifndef PT_KILL | |
68 | #define PT_KILL PTRACE_KILL | |
69 | #endif | |
70 | #ifndef PT_READ_U | |
71 | #define PT_READ_U PTRACE_PEEKUSR | |
72 | #endif | |
73 | ||
74 | #ifdef NSIG | |
75 | #define LINUXTHREAD_NSIG NSIG | |
76 | #else | |
77 | #ifdef _NSIG | |
78 | #define LINUXTHREAD_NSIG _NSIG | |
79 | #endif | |
80 | #endif | |
81 | ||
82 | extern int child_suppress_run; /* make inftarg.c non-runnable */ | |
83 | struct target_ops linuxthreads_ops; /* Forward declaration */ | |
84 | extern struct target_ops child_ops; /* target vector for inftarg.c */ | |
85 | ||
86 | static CORE_ADDR linuxthreads_handles; /* array of linuxthreads handles */ | |
87 | static CORE_ADDR linuxthreads_manager; /* pid of linuxthreads manager thread */ | |
88 | static CORE_ADDR linuxthreads_initial; /* pid of linuxthreads initial thread */ | |
89 | static CORE_ADDR linuxthreads_debug; /* linuxthreads internal debug flag */ | |
90 | static CORE_ADDR linuxthreads_num; /* number of valid handle entries */ | |
91 | ||
92 | static int linuxthreads_max; /* Maximum number of linuxthreads. | |
93 | Zero if this executable doesn't use | |
94 | threads, or wasn't linked with a | |
95 | debugger-friendly version of the | |
96 | linuxthreads library. */ | |
97 | ||
98 | static int linuxthreads_sizeof_handle; /* size of a linuxthreads handle */ | |
99 | static int linuxthreads_offset_descr; /* h_descr offset of the linuxthreads | |
100 | handle */ | |
101 | static int linuxthreads_offset_pid; /* p_pid offset of the linuxthreads | |
102 | descr */ | |
103 | ||
104 | static int linuxthreads_manager_pid; /* manager pid */ | |
105 | static int linuxthreads_initial_pid; /* initial pid */ | |
106 | ||
107 | /* These variables form a bag of threads with interesting status. If | |
108 | wait_thread (PID) finds that PID stopped for some interesting | |
109 | reason (i.e. anything other than stopped with SIGSTOP), then it | |
110 | records its status in this queue. linuxthreads_wait and | |
111 | linuxthreads_find_trap extract processes from here. */ | |
112 | static int *linuxthreads_wait_pid; /* wait array of pid */ | |
113 | static int *linuxthreads_wait_status; /* wait array of status */ | |
114 | static int linuxthreads_wait_last; /* index of last valid elt in | |
115 | linuxthreads_wait_{pid,status} */ | |
116 | ||
ed9a39eb | 117 | static sigset_t linuxthreads_block_mask; /* sigset without SIGCHLD */ |
d4f3574e SS |
118 | |
119 | static int linuxthreads_step_pid; /* current stepped pid */ | |
120 | static int linuxthreads_step_signo; /* current stepped target signal */ | |
121 | static int linuxthreads_exit_status; /* exit status of initial thread */ | |
122 | ||
123 | static int linuxthreads_inferior_pid; /* temporary internal inferior pid */ | |
124 | static int linuxthreads_breakpoint_pid; /* last pid that hit a breakpoint */ | |
125 | static int linuxthreads_attach_pending; /* attach command without wait */ | |
126 | ||
127 | static int linuxthreads_breakpoints_inserted; /* any breakpoints inserted */ | |
128 | ||
129 | /* LinuxThreads uses certain signals for communication between | |
130 | processes; we need to tell GDB to pass them through silently to the | |
131 | inferior. The LinuxThreads library has global variables we can | |
132 | read containing the relevant signal numbers, but since the signal | |
133 | numbers are chosen at run-time, those variables aren't initialized | |
134 | until the shared library's constructors have had a chance to run. */ | |
135 | ||
136 | struct linuxthreads_signal { | |
137 | ||
138 | /* The name of the LinuxThreads library variable that contains | |
139 | the signal number. */ | |
140 | char *var; | |
141 | ||
142 | /* True if this variable must exist for us to debug properly. */ | |
143 | int required; | |
144 | ||
145 | /* The variable's address in the inferior, or zero if the | |
146 | LinuxThreads library hasn't been loaded into this inferior yet. */ | |
147 | CORE_ADDR addr; | |
148 | ||
149 | /* The signal number, or zero if we don't know yet (either because | |
150 | we haven't found the variable, or it hasn't been initialized). | |
151 | This is an actual target signal number that you could pass to | |
152 | `kill', not a GDB signal number. */ | |
153 | int signal; | |
154 | ||
155 | /* GDB's original settings for `stop' and `print' for this signal. | |
156 | We restore them when the user selects a different executable. | |
157 | Invariant: if sig->signal != 0, then sig->{stop,print} contain | |
158 | the original settings. */ | |
159 | int stop, print; | |
160 | }; | |
161 | ||
162 | struct linuxthreads_signal linuxthreads_sig_restart = { | |
5c44784c | 163 | "__pthread_sig_restart", 1, 0, 0, 0, 0 |
d4f3574e SS |
164 | }; |
165 | struct linuxthreads_signal linuxthreads_sig_cancel = { | |
5c44784c | 166 | "__pthread_sig_cancel", 1, 0, 0, 0, 0 |
d4f3574e SS |
167 | }; |
168 | struct linuxthreads_signal linuxthreads_sig_debug = { | |
5c44784c | 169 | "__pthread_sig_debug", 0, 0, 0, 0, 0 |
d4f3574e SS |
170 | }; |
171 | ||
ed9a39eb JM |
172 | /* Set by thread_db module when it takes over the thread_stratum. |
173 | In that case we must: | |
174 | a) refrain from turning on the debug signal, and | |
175 | b) refrain from calling add_thread. */ | |
176 | ||
177 | int using_thread_db = 0; | |
178 | ||
d4f3574e SS |
179 | /* A table of breakpoint locations, one per PID. */ |
180 | static struct linuxthreads_breakpoint { | |
181 | CORE_ADDR pc; /* PC of breakpoint */ | |
182 | int pid; /* pid of breakpoint */ | |
183 | int step; /* whether the pc has been reached after sstep */ | |
184 | } *linuxthreads_breakpoint_zombie; /* Zombie breakpoints array */ | |
185 | static int linuxthreads_breakpoint_last; /* Last zombie breakpoint */ | |
186 | ||
187 | /* linuxthreads_{insert,remove}_breakpoint pass the breakpoint address | |
188 | to {insert,remove}_breakpoint via this variable, since | |
189 | iterate_active_threads doesn't provide any way to pass values | |
190 | through to the worker function. */ | |
191 | static CORE_ADDR linuxthreads_breakpoint_addr; | |
192 | ||
193 | #define REMOVE_BREAKPOINT_ZOMBIE(_i) \ | |
194 | { \ | |
195 | if ((_i) < linuxthreads_breakpoint_last) \ | |
196 | linuxthreads_breakpoint_zombie[(_i)] = \ | |
197 | linuxthreads_breakpoint_zombie[linuxthreads_breakpoint_last]; \ | |
198 | linuxthreads_breakpoint_last--; \ | |
199 | } | |
200 | ||
201 | ||
202 | \f | |
203 | #ifndef PTRACE_XFER_TYPE | |
204 | #define PTRACE_XFER_TYPE int | |
205 | #endif | |
206 | /* Check to see if the given thread is alive. */ | |
207 | static int | |
39f77062 | 208 | linuxthreads_thread_alive (ptid_t ptid) |
d4f3574e SS |
209 | { |
210 | errno = 0; | |
39f77062 KB |
211 | return ptrace (PT_READ_U, PIDGET (ptid), (PTRACE_ARG3_TYPE)0, 0) >= 0 |
212 | || errno == 0; | |
d4f3574e SS |
213 | } |
214 | ||
215 | /* On detach(), find a SIGTRAP status. If stop is non-zero, find a | |
216 | SIGSTOP one, too. | |
217 | ||
218 | Make sure PID is ready to run, and free of interference from our | |
219 | efforts to debug it (e.g., pending SIGSTOP or SIGTRAP signals). If | |
220 | STOP is zero, just look for a SIGTRAP. If STOP is non-zero, look | |
221 | for a SIGSTOP, too. Return non-zero if PID is alive and ready to | |
222 | run; return zero if PID is dead. | |
223 | ||
224 | PID may or may not be stopped at the moment, and we may or may not | |
225 | have waited for it already. We check the linuxthreads_wait bag in | |
226 | case we've already got a status for it. We may possibly wait for | |
227 | it ourselves. | |
228 | ||
229 | PID may have signals waiting to be delivered. If they're caused by | |
230 | our efforts to debug it, accept them with wait, but don't pass them | |
231 | through to PID. Do pass all other signals through. */ | |
232 | static int | |
fba45db2 | 233 | linuxthreads_find_trap (int pid, int stop) |
d4f3574e SS |
234 | { |
235 | int i; | |
236 | int rpid; | |
237 | int status; | |
238 | int found_stop = 0; | |
239 | int found_trap = 0; | |
240 | ||
241 | /* PID may have any number of signals pending. The kernel will | |
242 | report each of them to us via wait, and then it's up to us to | |
243 | pass them along to the process via ptrace, if we so choose. | |
244 | ||
245 | We need to paw through the whole set until we've found a SIGTRAP | |
246 | (or a SIGSTOP, if `stop' is set). We don't pass the SIGTRAP (or | |
247 | SIGSTOP) through, but we do re-send all the others, so PID will | |
248 | receive them when we resume it. */ | |
249 | int *wstatus = alloca (LINUXTHREAD_NSIG * sizeof (int)); | |
250 | int last = 0; | |
251 | ||
252 | /* Look at the pending status */ | |
253 | for (i = linuxthreads_wait_last; i >= 0; i--) | |
254 | if (linuxthreads_wait_pid[i] == pid) | |
255 | { | |
256 | status = linuxthreads_wait_status[i]; | |
257 | ||
258 | /* Delete the i'th member of the table. Since the table is | |
259 | unordered, we can do this simply by copying the table's | |
260 | last element to the i'th position, and shrinking the table | |
261 | by one element. */ | |
262 | if (i < linuxthreads_wait_last) | |
263 | { | |
264 | linuxthreads_wait_status[i] = | |
265 | linuxthreads_wait_status[linuxthreads_wait_last]; | |
266 | linuxthreads_wait_pid[i] = | |
267 | linuxthreads_wait_pid[linuxthreads_wait_last]; | |
268 | } | |
269 | linuxthreads_wait_last--; | |
270 | ||
271 | if (!WIFSTOPPED(status)) /* Thread has died */ | |
272 | return 0; | |
273 | ||
274 | if (WSTOPSIG(status) == SIGTRAP) | |
275 | { | |
276 | if (stop) | |
277 | found_trap = 1; | |
278 | else | |
279 | return 1; | |
280 | } | |
281 | else if (WSTOPSIG(status) == SIGSTOP) | |
282 | { | |
283 | if (stop) | |
284 | found_stop = 1; | |
285 | } | |
286 | else | |
287 | { | |
288 | wstatus[0] = status; | |
289 | last = 1; | |
290 | } | |
291 | ||
292 | break; | |
293 | } | |
294 | ||
295 | if (stop) | |
296 | { | |
297 | /* Make sure that we'll find what we're looking for. */ | |
298 | if (!found_trap) | |
ed9a39eb JM |
299 | { |
300 | kill (pid, SIGTRAP); | |
301 | } | |
d4f3574e | 302 | if (!found_stop) |
ed9a39eb JM |
303 | { |
304 | kill (pid, SIGSTOP); | |
305 | } | |
d4f3574e SS |
306 | } |
307 | ||
308 | /* Catch all status until SIGTRAP and optionally SIGSTOP show up. */ | |
309 | for (;;) | |
310 | { | |
ed9a39eb | 311 | /* resume the child every time... */ |
39f77062 | 312 | child_resume (pid_to_ptid (pid), 1, TARGET_SIGNAL_0); |
d4f3574e | 313 | |
ed9a39eb JM |
314 | /* loop as long as errno == EINTR: |
315 | waitpid syscall may be aborted due to GDB receiving a signal. | |
316 | FIXME: EINTR handling should no longer be necessary here, since | |
317 | we now block SIGCHLD except in an explicit sigsuspend call. */ | |
318 | ||
d4f3574e SS |
319 | for (;;) |
320 | { | |
321 | rpid = waitpid (pid, &status, __WCLONE); | |
322 | if (rpid > 0) | |
ed9a39eb JM |
323 | { |
324 | break; | |
325 | } | |
d4f3574e | 326 | if (errno == EINTR) |
ed9a39eb JM |
327 | { |
328 | continue; | |
329 | } | |
d4f3574e SS |
330 | |
331 | /* There are a few reasons the wait call above may have | |
332 | failed. If the thread manager dies, its children get | |
333 | reparented, and this interferes with GDB waiting for | |
334 | them, in some cases. Another possibility is that the | |
335 | initial thread was not cloned, so calling wait with | |
336 | __WCLONE won't find it. I think neither of these should | |
337 | occur in modern Linux kernels --- they don't seem to in | |
338 | 2.0.36. */ | |
339 | rpid = waitpid (pid, &status, 0); | |
340 | if (rpid > 0) | |
ed9a39eb JM |
341 | { |
342 | break; | |
343 | } | |
d4f3574e | 344 | if (errno != EINTR) |
ed9a39eb | 345 | perror_with_name ("find_trap/waitpid"); |
d4f3574e SS |
346 | } |
347 | ||
348 | if (!WIFSTOPPED(status)) /* Thread has died */ | |
349 | return 0; | |
350 | ||
351 | if (WSTOPSIG(status) == SIGTRAP) | |
352 | if (!stop || found_stop) | |
353 | break; | |
354 | else | |
355 | found_trap = 1; | |
356 | else if (WSTOPSIG(status) != SIGSTOP) | |
357 | wstatus[last++] = status; | |
358 | else if (stop) | |
5c44784c JM |
359 | { |
360 | if (found_trap) | |
361 | break; | |
362 | else | |
363 | found_stop = 1; | |
364 | } | |
d4f3574e SS |
365 | } |
366 | ||
367 | /* Resend any other signals we noticed to the thread, to be received | |
368 | when we continue it. */ | |
369 | while (--last >= 0) | |
ed9a39eb JM |
370 | { |
371 | kill (pid, WSTOPSIG(wstatus[last])); | |
372 | } | |
d4f3574e SS |
373 | |
374 | return 1; | |
375 | } | |
376 | ||
39f77062 | 377 | /* Cleanup stub for save_inferior_ptid. */ |
d4f3574e | 378 | static void |
39f77062 | 379 | restore_inferior_ptid (void *arg) |
d4f3574e | 380 | { |
39f77062 KB |
381 | ptid_t *saved_ptid_ptr = arg; |
382 | inferior_ptid = *saved_ptid_ptr; | |
b8c9b27d | 383 | xfree (arg); |
d4f3574e SS |
384 | } |
385 | ||
39f77062 | 386 | /* Register a cleanup to restore the value of inferior_ptid. */ |
d4f3574e | 387 | static struct cleanup * |
39f77062 | 388 | save_inferior_ptid (void) |
d4f3574e | 389 | { |
39f77062 | 390 | ptid_t *saved_ptid_ptr; |
a91f7ea9 | 391 | |
39f77062 KB |
392 | saved_ptid_ptr = xmalloc (sizeof (ptid_t)); |
393 | *saved_ptid_ptr = inferior_ptid; | |
394 | return make_cleanup (restore_inferior_ptid, saved_ptid_ptr); | |
d4f3574e SS |
395 | } |
396 | ||
397 | static void | |
fba45db2 | 398 | sigchld_handler (int signo) |
d4f3574e SS |
399 | { |
400 | /* This handler is used to get an EINTR while doing waitpid() | |
401 | when an event is received */ | |
402 | } | |
403 | ||
404 | /* Have we already collected a wait status for PID in the | |
405 | linuxthreads_wait bag? */ | |
406 | static int | |
fba45db2 | 407 | linuxthreads_pending_status (int pid) |
d4f3574e SS |
408 | { |
409 | int i; | |
410 | for (i = linuxthreads_wait_last; i >= 0; i--) | |
411 | if (linuxthreads_wait_pid[i] == pid) | |
412 | return 1; | |
413 | return 0; | |
414 | } | |
415 | ||
416 | \f | |
417 | /* Internal linuxthreads signal management */ | |
418 | ||
419 | /* Check in OBJFILE for the variable that holds the number for signal SIG. | |
420 | We assume that we've already found other LinuxThreads-ish variables | |
421 | in OBJFILE, so we complain if it's required, but not there. | |
422 | Return true iff things are okay. */ | |
423 | static int | |
fba45db2 | 424 | find_signal_var (struct linuxthreads_signal *sig, struct objfile *objfile) |
d4f3574e SS |
425 | { |
426 | struct minimal_symbol *ms = lookup_minimal_symbol (sig->var, NULL, objfile); | |
427 | ||
428 | if (! ms) | |
429 | { | |
430 | if (sig->required) | |
431 | { | |
432 | fprintf_unfiltered (gdb_stderr, | |
433 | "Unable to find linuxthreads symbol \"%s\"\n", | |
434 | sig->var); | |
435 | return 0; | |
436 | } | |
437 | else | |
438 | { | |
439 | sig->addr = 0; | |
440 | return 1; | |
441 | } | |
442 | } | |
443 | ||
444 | sig->addr = SYMBOL_VALUE_ADDRESS (ms); | |
445 | ||
446 | return 1; | |
447 | } | |
448 | ||
449 | static int | |
fba45db2 | 450 | find_all_signal_vars (struct objfile *objfile) |
d4f3574e SS |
451 | { |
452 | return ( find_signal_var (&linuxthreads_sig_restart, objfile) | |
453 | && find_signal_var (&linuxthreads_sig_cancel, objfile) | |
454 | && find_signal_var (&linuxthreads_sig_debug, objfile)); | |
455 | } | |
456 | ||
457 | /* A struct complaint isn't appropriate here. */ | |
458 | static int complained_cannot_determine_thread_signal_number = 0; | |
459 | ||
460 | /* Check to see if the variable holding the signal number for SIG has | |
461 | been initialized yet. If it has, tell GDB to pass that signal | |
462 | through to the inferior silently. */ | |
463 | static void | |
fba45db2 | 464 | check_signal_number (struct linuxthreads_signal *sig) |
d4f3574e SS |
465 | { |
466 | int num; | |
467 | ||
468 | if (sig->signal) | |
469 | /* We already know this signal number. */ | |
470 | return; | |
471 | ||
472 | if (! sig->addr) | |
473 | /* We don't know the variable's address yet. */ | |
474 | return; | |
475 | ||
476 | if (target_read_memory (sig->addr, (char *)&num, sizeof (num)) | |
477 | != 0) | |
478 | { | |
479 | /* If this happens once, it'll probably happen for all the | |
480 | signals, so only complain once. */ | |
481 | if (! complained_cannot_determine_thread_signal_number) | |
482 | warning ("Cannot determine thread signal number; " | |
483 | "GDB may report spurious signals."); | |
484 | complained_cannot_determine_thread_signal_number = 1; | |
485 | return; | |
486 | } | |
487 | ||
488 | if (num == 0) | |
489 | /* It hasn't been initialized yet. */ | |
490 | return; | |
491 | ||
492 | /* We know sig->signal was zero, and is becoming non-zero, so it's | |
493 | okay to sample GDB's original settings. */ | |
494 | sig->signal = num; | |
495 | sig->stop = signal_stop_update (target_signal_from_host (num), 0); | |
496 | sig->print = signal_print_update (target_signal_from_host (num), 0); | |
497 | } | |
498 | ||
ed9a39eb | 499 | void |
fba45db2 | 500 | check_all_signal_numbers (void) |
d4f3574e SS |
501 | { |
502 | /* If this isn't a LinuxThreads program, quit early. */ | |
503 | if (! linuxthreads_max) | |
504 | return; | |
505 | ||
506 | check_signal_number (&linuxthreads_sig_restart); | |
507 | check_signal_number (&linuxthreads_sig_cancel); | |
508 | check_signal_number (&linuxthreads_sig_debug); | |
509 | ||
510 | /* handle linuxthread exit */ | |
511 | if (linuxthreads_sig_debug.signal | |
512 | || linuxthreads_sig_restart.signal) | |
513 | { | |
514 | struct sigaction sact; | |
515 | ||
516 | sact.sa_handler = sigchld_handler; | |
517 | sigemptyset(&sact.sa_mask); | |
518 | sact.sa_flags = 0; | |
ed9a39eb | 519 | |
d4f3574e SS |
520 | if (linuxthreads_sig_debug.signal > 0) |
521 | sigaction(linuxthreads_sig_cancel.signal, &sact, NULL); | |
522 | else | |
523 | sigaction(linuxthreads_sig_restart.signal, &sact, NULL); | |
524 | } | |
525 | } | |
526 | ||
527 | ||
528 | /* Restore GDB's original settings for SIG. | |
529 | This should only be called when we're no longer sure if we're | |
530 | talking to an executable that uses LinuxThreads, so we clear the | |
531 | signal number and variable address too. */ | |
532 | static void | |
fba45db2 | 533 | restore_signal (struct linuxthreads_signal *sig) |
d4f3574e SS |
534 | { |
535 | if (! sig->signal) | |
536 | return; | |
537 | ||
538 | /* We know sig->signal was non-zero, and is becoming zero, so it's | |
539 | okay to restore GDB's original settings. */ | |
540 | signal_stop_update (target_signal_from_host (sig->signal), sig->stop); | |
541 | signal_print_update (target_signal_from_host (sig->signal), sig->print); | |
542 | ||
543 | sig->signal = 0; | |
544 | sig->addr = 0; | |
545 | } | |
546 | ||
547 | ||
548 | /* Restore GDB's original settings for all LinuxThreads signals. | |
549 | This should only be called when we're no longer sure if we're | |
550 | talking to an executable that uses LinuxThreads, so we clear the | |
551 | signal number and variable address too. */ | |
552 | static void | |
fba45db2 | 553 | restore_all_signals (void) |
d4f3574e SS |
554 | { |
555 | restore_signal (&linuxthreads_sig_restart); | |
556 | restore_signal (&linuxthreads_sig_cancel); | |
557 | restore_signal (&linuxthreads_sig_debug); | |
558 | ||
559 | /* If it happens again, we should complain again. */ | |
560 | complained_cannot_determine_thread_signal_number = 0; | |
561 | } | |
562 | ||
563 | ||
564 | \f | |
565 | ||
566 | /* Apply FUNC to the pid of each active thread. This consults the | |
567 | inferior's handle table to find active threads. | |
568 | ||
569 | If ALL is non-zero, process all threads. | |
570 | If ALL is zero, skip threads with pending status. */ | |
571 | static void | |
064002de | 572 | iterate_active_threads (void (*func) (int), int all) |
d4f3574e SS |
573 | { |
574 | CORE_ADDR descr; | |
575 | int pid; | |
576 | int i; | |
577 | int num; | |
578 | ||
579 | read_memory (linuxthreads_num, (char *)&num, sizeof (int)); | |
580 | ||
581 | for (i = 0; i < linuxthreads_max && num > 0; i++) | |
582 | { | |
583 | read_memory (linuxthreads_handles + | |
584 | linuxthreads_sizeof_handle * i + linuxthreads_offset_descr, | |
585 | (char *)&descr, sizeof (void *)); | |
586 | if (descr) | |
587 | { | |
588 | num--; | |
589 | read_memory (descr + linuxthreads_offset_pid, | |
590 | (char *)&pid, sizeof (pid_t)); | |
591 | if (pid > 0 && pid != linuxthreads_manager_pid | |
592 | && (all || (!linuxthreads_pending_status (pid)))) | |
593 | (*func)(pid); | |
594 | } | |
595 | } | |
d4f3574e SS |
596 | } |
597 | ||
598 | /* Insert a thread breakpoint at linuxthreads_breakpoint_addr. | |
599 | This is the worker function for linuxthreads_insert_breakpoint, | |
600 | which passes it to iterate_active_threads. */ | |
601 | static void | |
fba45db2 | 602 | insert_breakpoint (int pid) |
d4f3574e SS |
603 | { |
604 | int j; | |
605 | ||
606 | /* Remove (if any) the positive zombie breakpoint. */ | |
607 | for (j = linuxthreads_breakpoint_last; j >= 0; j--) | |
608 | if (linuxthreads_breakpoint_zombie[j].pid == pid) | |
609 | { | |
610 | if ((linuxthreads_breakpoint_zombie[j].pc - DECR_PC_AFTER_BREAK | |
611 | == linuxthreads_breakpoint_addr) | |
612 | && !linuxthreads_breakpoint_zombie[j].step) | |
613 | REMOVE_BREAKPOINT_ZOMBIE(j); | |
614 | break; | |
615 | } | |
616 | } | |
617 | ||
618 | /* Note that we're about to remove a thread breakpoint at | |
619 | linuxthreads_breakpoint_addr. | |
620 | ||
621 | This is the worker function for linuxthreads_remove_breakpoint, | |
622 | which passes it to iterate_active_threads. The actual work of | |
623 | overwriting the breakpoint instruction is done by | |
624 | child_ops.to_remove_breakpoint; here, we simply create a zombie | |
625 | breakpoint if the thread's PC is pointing at the breakpoint being | |
626 | removed. */ | |
627 | static void | |
fba45db2 | 628 | remove_breakpoint (int pid) |
d4f3574e SS |
629 | { |
630 | int j; | |
631 | ||
632 | /* Insert a positive zombie breakpoint (if needed). */ | |
633 | for (j = 0; j <= linuxthreads_breakpoint_last; j++) | |
634 | if (linuxthreads_breakpoint_zombie[j].pid == pid) | |
635 | break; | |
636 | ||
39f77062 KB |
637 | if (in_thread_list (pid_to_ptid (pid)) |
638 | && linuxthreads_thread_alive (pid_to_ptid (pid))) | |
d4f3574e | 639 | { |
39f77062 | 640 | CORE_ADDR pc = read_pc_pid (pid_to_ptid (pid)); |
d4f3574e SS |
641 | if (linuxthreads_breakpoint_addr == pc - DECR_PC_AFTER_BREAK |
642 | && j > linuxthreads_breakpoint_last) | |
643 | { | |
644 | linuxthreads_breakpoint_zombie[j].pid = pid; | |
645 | linuxthreads_breakpoint_zombie[j].pc = pc; | |
646 | linuxthreads_breakpoint_zombie[j].step = 0; | |
647 | linuxthreads_breakpoint_last++; | |
648 | } | |
649 | } | |
650 | } | |
651 | ||
652 | /* Kill a thread */ | |
653 | static void | |
fba45db2 | 654 | kill_thread (int pid) |
d4f3574e | 655 | { |
39f77062 | 656 | if (in_thread_list (pid_to_ptid (pid))) |
ed9a39eb JM |
657 | { |
658 | ptrace (PT_KILL, pid, (PTRACE_ARG3_TYPE) 0, 0); | |
659 | } | |
d4f3574e | 660 | else |
ed9a39eb JM |
661 | { |
662 | kill (pid, SIGKILL); | |
663 | } | |
d4f3574e SS |
664 | } |
665 | ||
666 | /* Resume a thread */ | |
667 | static void | |
fba45db2 | 668 | resume_thread (int pid) |
d4f3574e | 669 | { |
39f77062 KB |
670 | if (pid != PIDGET (inferior_ptid) |
671 | && in_thread_list (pid_to_ptid (pid)) | |
672 | && linuxthreads_thread_alive (pid_to_ptid (pid))) | |
5c44784c JM |
673 | { |
674 | if (pid == linuxthreads_step_pid) | |
ed9a39eb | 675 | { |
39f77062 | 676 | child_resume (pid_to_ptid (pid), 1, linuxthreads_step_signo); |
ed9a39eb | 677 | } |
5c44784c | 678 | else |
ed9a39eb | 679 | { |
39f77062 | 680 | child_resume (pid_to_ptid (pid), 0, TARGET_SIGNAL_0); |
ed9a39eb | 681 | } |
5c44784c | 682 | } |
d4f3574e SS |
683 | } |
684 | ||
685 | /* Detach a thread */ | |
686 | static void | |
fba45db2 | 687 | detach_thread (int pid) |
d4f3574e | 688 | { |
39f77062 KB |
689 | ptid_t ptid = pid_to_ptid (pid); |
690 | ||
691 | if (in_thread_list (ptid) && linuxthreads_thread_alive (ptid)) | |
d4f3574e SS |
692 | { |
693 | /* Remove pending SIGTRAP and SIGSTOP */ | |
694 | linuxthreads_find_trap (pid, 1); | |
695 | ||
39f77062 | 696 | inferior_ptid = ptid; |
d4f3574e | 697 | detach (TARGET_SIGNAL_0); |
39f77062 | 698 | inferior_ptid = pid_to_ptid (linuxthreads_manager_pid); |
d4f3574e SS |
699 | } |
700 | } | |
701 | ||
ed9a39eb JM |
702 | /* Attach a thread */ |
703 | void | |
fba45db2 | 704 | attach_thread (int pid) |
ed9a39eb JM |
705 | { |
706 | if (ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 0, 0) != 0) | |
707 | perror_with_name ("attach_thread"); | |
708 | } | |
709 | ||
d4f3574e SS |
710 | /* Stop a thread */ |
711 | static void | |
fba45db2 | 712 | stop_thread (int pid) |
d4f3574e | 713 | { |
39f77062 | 714 | if (pid != PIDGET (inferior_ptid)) |
5c44784c | 715 | { |
39f77062 | 716 | if (in_thread_list (pid_to_ptid (pid))) |
ed9a39eb JM |
717 | { |
718 | kill (pid, SIGSTOP); | |
719 | } | |
5c44784c JM |
720 | else if (ptrace (PT_ATTACH, pid, (PTRACE_ARG3_TYPE) 0, 0) == 0) |
721 | { | |
722 | if (!linuxthreads_attach_pending) | |
39f77062 KB |
723 | printf_filtered ("[New %s]\n", |
724 | target_pid_to_str (pid_to_ptid (pid))); | |
725 | add_thread (pid_to_ptid (pid)); | |
5c44784c | 726 | if (linuxthreads_sig_debug.signal) |
ed9a39eb JM |
727 | { |
728 | /* After a new thread in glibc 2.1 signals gdb its existence, | |
729 | it suspends itself and wait for linuxthreads_sig_restart, | |
730 | now we can wake it up. */ | |
731 | kill (pid, linuxthreads_sig_restart.signal); | |
732 | } | |
5c44784c JM |
733 | } |
734 | else | |
735 | perror_with_name ("ptrace in stop_thread"); | |
736 | } | |
d4f3574e SS |
737 | } |
738 | ||
739 | /* Wait for a thread */ | |
740 | static void | |
fba45db2 | 741 | wait_thread (int pid) |
d4f3574e SS |
742 | { |
743 | int status; | |
744 | int rpid; | |
745 | ||
39f77062 | 746 | if (pid != PIDGET (inferior_ptid) && in_thread_list (pid_to_ptid (pid))) |
d4f3574e | 747 | { |
ed9a39eb JM |
748 | /* loop as long as errno == EINTR: |
749 | waitpid syscall may be aborted if GDB receives a signal. | |
750 | FIXME: EINTR handling should no longer be necessary here, since | |
751 | we now block SIGCHLD except during an explicit sigsuspend call. */ | |
d4f3574e SS |
752 | for (;;) |
753 | { | |
754 | /* Get first pid status. */ | |
755 | rpid = waitpid(pid, &status, __WCLONE); | |
756 | if (rpid > 0) | |
ed9a39eb JM |
757 | { |
758 | break; | |
759 | } | |
d4f3574e | 760 | if (errno == EINTR) |
ed9a39eb JM |
761 | { |
762 | continue; | |
763 | } | |
d4f3574e SS |
764 | |
765 | /* There are two reasons this might have failed: | |
766 | ||
767 | 1) PID is the initial thread, which wasn't cloned, so | |
768 | passing the __WCLONE flag to waitpid prevented us from | |
769 | finding it. | |
770 | ||
771 | 2) The manager thread is the parent of all but the | |
772 | initial thread; if it dies, the children will all be | |
773 | reparented to init, which will wait for them. This means | |
774 | our call to waitpid won't find them. | |
775 | ||
776 | Actually, based on a casual look at the 2.0.36 kernel | |
777 | code, I don't think either of these cases happen. But I | |
778 | don't have things set up for remotely debugging the | |
779 | kernel, so I'm not sure. And perhaps older kernels | |
780 | didn't work. */ | |
781 | rpid = waitpid(pid, &status, 0); | |
782 | if (rpid > 0) | |
ed9a39eb JM |
783 | { |
784 | break; | |
785 | } | |
39f77062 | 786 | if (errno != EINTR && linuxthreads_thread_alive (pid_to_ptid (pid))) |
ed9a39eb | 787 | perror_with_name ("wait_thread/waitpid"); |
d4f3574e SS |
788 | |
789 | /* the thread is dead. */ | |
790 | return; | |
791 | } | |
792 | if (!WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP) | |
793 | { | |
794 | linuxthreads_wait_pid[++linuxthreads_wait_last] = pid; | |
795 | linuxthreads_wait_status[linuxthreads_wait_last] = status; | |
796 | } | |
797 | } | |
798 | } | |
799 | ||
800 | /* Walk through the linuxthreads handles in order to detect all | |
801 | threads and stop them */ | |
802 | static void | |
fba45db2 | 803 | update_stop_threads (int test_pid) |
d4f3574e SS |
804 | { |
805 | struct cleanup *old_chain = NULL; | |
806 | ||
807 | check_all_signal_numbers (); | |
808 | ||
809 | if (linuxthreads_manager_pid == 0) | |
810 | { | |
811 | if (linuxthreads_manager) | |
812 | { | |
39f77062 | 813 | if (test_pid > 0 && test_pid != PIDGET (inferior_ptid)) |
d4f3574e | 814 | { |
39f77062 KB |
815 | old_chain = save_inferior_ptid (); |
816 | inferior_ptid = pid_to_ptid (test_pid); | |
d4f3574e SS |
817 | } |
818 | read_memory (linuxthreads_manager, | |
819 | (char *)&linuxthreads_manager_pid, sizeof (pid_t)); | |
820 | } | |
821 | if (linuxthreads_initial) | |
822 | { | |
39f77062 | 823 | if (test_pid > 0 && test_pid != PIDGET (inferior_ptid)) |
d4f3574e | 824 | { |
39f77062 KB |
825 | old_chain = save_inferior_ptid (); |
826 | inferior_ptid = pid_to_ptid (test_pid); | |
d4f3574e SS |
827 | } |
828 | read_memory(linuxthreads_initial, | |
829 | (char *)&linuxthreads_initial_pid, sizeof (pid_t)); | |
830 | } | |
831 | } | |
832 | ||
833 | if (linuxthreads_manager_pid != 0) | |
834 | { | |
835 | if (old_chain == NULL && test_pid > 0 && | |
39f77062 KB |
836 | test_pid != PIDGET (inferior_ptid) |
837 | && linuxthreads_thread_alive (pid_to_ptid (test_pid))) | |
d4f3574e | 838 | { |
39f77062 KB |
839 | old_chain = save_inferior_ptid (); |
840 | inferior_ptid = pid_to_ptid (test_pid); | |
d4f3574e SS |
841 | } |
842 | ||
39f77062 | 843 | if (linuxthreads_thread_alive (inferior_ptid)) |
d4f3574e SS |
844 | { |
845 | if (test_pid > 0) | |
846 | { | |
847 | if (test_pid != linuxthreads_manager_pid | |
848 | && !linuxthreads_pending_status (linuxthreads_manager_pid)) | |
849 | { | |
850 | stop_thread (linuxthreads_manager_pid); | |
851 | wait_thread (linuxthreads_manager_pid); | |
852 | } | |
39f77062 | 853 | if (!in_thread_list (pid_to_ptid (test_pid))) |
d4f3574e SS |
854 | { |
855 | if (!linuxthreads_attach_pending) | |
ed9a39eb | 856 | printf_filtered ("[New %s]\n", |
39f77062 KB |
857 | target_pid_to_str (pid_to_ptid (test_pid))); |
858 | add_thread (pid_to_ptid (test_pid)); | |
d4f3574e | 859 | if (linuxthreads_sig_debug.signal |
39f77062 | 860 | && PIDGET (inferior_ptid) == test_pid) |
ed9a39eb JM |
861 | { |
862 | /* After a new thread in glibc 2.1 signals gdb its | |
863 | existence, it suspends itself and wait for | |
864 | linuxthreads_sig_restart, now we can wake it up. */ | |
865 | kill (test_pid, linuxthreads_sig_restart.signal); | |
866 | } | |
d4f3574e SS |
867 | } |
868 | } | |
869 | iterate_active_threads (stop_thread, 0); | |
870 | iterate_active_threads (wait_thread, 0); | |
871 | } | |
872 | } | |
873 | ||
874 | if (old_chain != NULL) | |
875 | do_cleanups (old_chain); | |
876 | } | |
877 | ||
11cf8741 JM |
878 | /* This routine is called whenever a new symbol table is read in, or |
879 | when all symbol tables are removed. linux-thread event handling | |
880 | can only be initialized when we find the right variables in | |
881 | libpthread.so. Since it's a shared library, those variables don't | |
882 | show up until the library gets mapped and the symbol table is read | |
883 | in. */ | |
884 | ||
885 | /* This new_objfile event is now managed by a chained function pointer. | |
886 | * It is the callee's responsability to call the next client on the chain. | |
887 | */ | |
888 | ||
889 | /* Saved pointer to previous owner of the new_objfile event. */ | |
507f3c78 | 890 | static void (*target_new_objfile_chain) (struct objfile *); |
d4f3574e SS |
891 | |
892 | void | |
fba45db2 | 893 | linuxthreads_new_objfile (struct objfile *objfile) |
d4f3574e SS |
894 | { |
895 | struct minimal_symbol *ms; | |
896 | ||
ed9a39eb JM |
897 | /* Call predecessor on chain, if any. |
898 | Calling the new module first allows it to dominate, | |
899 | if it finds its compatible libraries. */ | |
900 | ||
901 | if (target_new_objfile_chain) | |
902 | target_new_objfile_chain (objfile); | |
903 | ||
d4f3574e SS |
904 | if (!objfile) |
905 | { | |
906 | /* We're starting an entirely new executable, so we can no | |
907 | longer be sure that it uses LinuxThreads. Restore the signal | |
908 | flags to their original states. */ | |
909 | restore_all_signals (); | |
910 | ||
911 | /* Indicate that we don't know anything's address any more. */ | |
912 | linuxthreads_max = 0; | |
913 | ||
11cf8741 | 914 | goto quit; |
d4f3574e SS |
915 | } |
916 | ||
917 | /* If we've already found our variables in another objfile, don't | |
918 | bother looking for them again. */ | |
919 | if (linuxthreads_max) | |
11cf8741 | 920 | goto quit; |
d4f3574e SS |
921 | |
922 | if (! lookup_minimal_symbol ("__pthread_initial_thread", NULL, objfile)) | |
923 | /* This object file isn't the pthreads library. */ | |
11cf8741 | 924 | goto quit; |
d4f3574e SS |
925 | |
926 | if ((ms = lookup_minimal_symbol ("__pthread_threads_debug", | |
927 | NULL, objfile)) == NULL) | |
928 | { | |
929 | /* The debugging-aware libpthreads is not present in this objfile */ | |
930 | warning ("\ | |
931 | This program seems to use POSIX threads, but the thread library used\n\ | |
932 | does not support debugging. This may make using GDB difficult. Don't\n\ | |
933 | set breakpoints or single-step through code that might be executed by\n\ | |
934 | any thread other than the main thread."); | |
11cf8741 | 935 | goto quit; |
d4f3574e SS |
936 | } |
937 | linuxthreads_debug = SYMBOL_VALUE_ADDRESS (ms); | |
938 | ||
939 | /* Read internal structures configuration */ | |
940 | if ((ms = lookup_minimal_symbol ("__pthread_sizeof_handle", | |
941 | NULL, objfile)) == NULL | |
942 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), | |
943 | (char *)&linuxthreads_sizeof_handle, | |
944 | sizeof (linuxthreads_sizeof_handle)) != 0) | |
945 | { | |
946 | fprintf_unfiltered (gdb_stderr, | |
947 | "Unable to find linuxthreads symbol \"%s\"\n", | |
948 | "__pthread_sizeof_handle"); | |
11cf8741 | 949 | goto quit; |
d4f3574e SS |
950 | } |
951 | ||
952 | if ((ms = lookup_minimal_symbol ("__pthread_offsetof_descr", | |
953 | NULL, objfile)) == NULL | |
954 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), | |
955 | (char *)&linuxthreads_offset_descr, | |
956 | sizeof (linuxthreads_offset_descr)) != 0) | |
957 | { | |
958 | fprintf_unfiltered (gdb_stderr, | |
959 | "Unable to find linuxthreads symbol \"%s\"\n", | |
960 | "__pthread_offsetof_descr"); | |
11cf8741 | 961 | goto quit; |
d4f3574e SS |
962 | } |
963 | ||
964 | if ((ms = lookup_minimal_symbol ("__pthread_offsetof_pid", | |
965 | NULL, objfile)) == NULL | |
966 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), | |
967 | (char *)&linuxthreads_offset_pid, | |
968 | sizeof (linuxthreads_offset_pid)) != 0) | |
969 | { | |
970 | fprintf_unfiltered (gdb_stderr, | |
971 | "Unable to find linuxthreads symbol \"%s\"\n", | |
972 | "__pthread_offsetof_pid"); | |
11cf8741 | 973 | goto quit; |
d4f3574e SS |
974 | } |
975 | ||
976 | if (! find_all_signal_vars (objfile)) | |
11cf8741 | 977 | goto quit; |
d4f3574e SS |
978 | |
979 | /* Read adresses of internal structures to access */ | |
980 | if ((ms = lookup_minimal_symbol ("__pthread_handles", | |
981 | NULL, objfile)) == NULL) | |
982 | { | |
983 | fprintf_unfiltered (gdb_stderr, | |
984 | "Unable to find linuxthreads symbol \"%s\"\n", | |
985 | "__pthread_handles"); | |
11cf8741 | 986 | goto quit; |
d4f3574e SS |
987 | } |
988 | linuxthreads_handles = SYMBOL_VALUE_ADDRESS (ms); | |
989 | ||
990 | if ((ms = lookup_minimal_symbol ("__pthread_handles_num", | |
991 | NULL, objfile)) == NULL) | |
992 | { | |
993 | fprintf_unfiltered (gdb_stderr, | |
994 | "Unable to find linuxthreads symbol \"%s\"\n", | |
995 | "__pthread_handles_num"); | |
11cf8741 | 996 | goto quit; |
d4f3574e SS |
997 | } |
998 | linuxthreads_num = SYMBOL_VALUE_ADDRESS (ms); | |
999 | ||
1000 | if ((ms = lookup_minimal_symbol ("__pthread_manager_thread", | |
1001 | NULL, objfile)) == NULL) | |
1002 | { | |
1003 | fprintf_unfiltered (gdb_stderr, | |
1004 | "Unable to find linuxthreads symbol \"%s\"\n", | |
1005 | "__pthread_manager_thread"); | |
11cf8741 | 1006 | goto quit; |
d4f3574e SS |
1007 | } |
1008 | linuxthreads_manager = SYMBOL_VALUE_ADDRESS (ms) + linuxthreads_offset_pid; | |
1009 | ||
1010 | if ((ms = lookup_minimal_symbol ("__pthread_initial_thread", | |
1011 | NULL, objfile)) == NULL) | |
1012 | { | |
1013 | fprintf_unfiltered (gdb_stderr, | |
1014 | "Unable to find linuxthreads symbol \"%s\"\n", | |
1015 | "__pthread_initial_thread"); | |
11cf8741 | 1016 | goto quit; |
d4f3574e SS |
1017 | } |
1018 | linuxthreads_initial = SYMBOL_VALUE_ADDRESS (ms) + linuxthreads_offset_pid; | |
1019 | ||
1020 | /* Search for this last, so it won't be set to a non-zero value unless | |
1021 | we successfully found all the symbols above. */ | |
1022 | if ((ms = lookup_minimal_symbol ("__pthread_threads_max", | |
1023 | NULL, objfile)) == NULL | |
1024 | || target_read_memory (SYMBOL_VALUE_ADDRESS (ms), | |
1025 | (char *)&linuxthreads_max, | |
1026 | sizeof (linuxthreads_max)) != 0) | |
1027 | { | |
1028 | fprintf_unfiltered (gdb_stderr, | |
1029 | "Unable to find linuxthreads symbol \"%s\"\n", | |
1030 | "__pthread_threads_max"); | |
11cf8741 | 1031 | goto quit; |
d4f3574e SS |
1032 | } |
1033 | ||
1034 | /* Allocate gdb internal structures */ | |
1035 | linuxthreads_wait_pid = | |
1036 | (int *) xmalloc (sizeof (int) * (linuxthreads_max + 1)); | |
1037 | linuxthreads_wait_status = | |
1038 | (int *) xmalloc (sizeof (int) * (linuxthreads_max + 1)); | |
1039 | linuxthreads_breakpoint_zombie = (struct linuxthreads_breakpoint *) | |
1040 | xmalloc (sizeof (struct linuxthreads_breakpoint) * (linuxthreads_max + 1)); | |
1041 | ||
39f77062 | 1042 | if (PIDGET (inferior_ptid) != 0 && |
ed9a39eb JM |
1043 | !linuxthreads_attach_pending && |
1044 | !using_thread_db) /* suppressed by thread_db module */ | |
d4f3574e SS |
1045 | { |
1046 | int on = 1; | |
ed9a39eb | 1047 | |
d4f3574e SS |
1048 | target_write_memory (linuxthreads_debug, (char *)&on, sizeof (on)); |
1049 | linuxthreads_attach_pending = 1; | |
39f77062 | 1050 | update_stop_threads (PIDGET (inferior_ptid)); |
d4f3574e SS |
1051 | linuxthreads_attach_pending = 0; |
1052 | } | |
11cf8741 | 1053 | |
ed9a39eb JM |
1054 | check_all_signal_numbers (); |
1055 | ||
11cf8741 | 1056 | quit: |
d4f3574e SS |
1057 | } |
1058 | ||
1059 | /* If we have switched threads from a one that stopped at breakpoint, | |
e02bc4cc DS |
1060 | return 1 otherwise 0. |
1061 | ||
1062 | Note that this implementation is potentially redundant now that | |
1063 | default_prepare_to_proceed() has been added. */ | |
d4f3574e SS |
1064 | |
1065 | int | |
fba45db2 | 1066 | linuxthreads_prepare_to_proceed (int step) |
d4f3574e SS |
1067 | { |
1068 | if (!linuxthreads_max | |
1069 | || !linuxthreads_manager_pid | |
1070 | || !linuxthreads_breakpoint_pid | |
39f77062 KB |
1071 | || !breakpoint_here_p ( |
1072 | read_pc_pid (pid_to_ptid (linuxthreads_breakpoint_pid)))) | |
d4f3574e SS |
1073 | return 0; |
1074 | ||
1075 | if (step) | |
1076 | { | |
1077 | /* Mark the current inferior as single stepping process. */ | |
39f77062 | 1078 | linuxthreads_step_pid = PIDGET (inferior_ptid); |
d4f3574e SS |
1079 | } |
1080 | ||
1081 | linuxthreads_inferior_pid = linuxthreads_breakpoint_pid; | |
1082 | return linuxthreads_breakpoint_pid; | |
1083 | } | |
1084 | ||
1085 | /* Convert a pid to printable form. */ | |
1086 | ||
1087 | char * | |
39f77062 | 1088 | linuxthreads_pid_to_str (ptid_t ptid) |
d4f3574e SS |
1089 | { |
1090 | static char buf[100]; | |
39f77062 | 1091 | int pid = PIDGET (ptid); |
d4f3574e SS |
1092 | |
1093 | sprintf (buf, "%s %d%s", linuxthreads_max ? "Thread" : "Pid", pid, | |
1094 | (pid == linuxthreads_manager_pid) ? " (manager thread)" | |
1095 | : (pid == linuxthreads_initial_pid) ? " (initial thread)" | |
1096 | : ""); | |
1097 | ||
1098 | return buf; | |
1099 | } | |
1100 | ||
1101 | /* Attach to process PID, then initialize for debugging it | |
1102 | and wait for the trace-trap that results from attaching. */ | |
1103 | ||
1104 | static void | |
fba45db2 | 1105 | linuxthreads_attach (char *args, int from_tty) |
d4f3574e SS |
1106 | { |
1107 | if (!args) | |
1108 | error_no_arg ("process-id to attach"); | |
1109 | ||
1110 | push_target (&linuxthreads_ops); | |
1111 | linuxthreads_breakpoints_inserted = 1; | |
1112 | linuxthreads_breakpoint_last = -1; | |
1113 | linuxthreads_wait_last = -1; | |
67aaefa2 | 1114 | WSETSTOP (linuxthreads_exit_status, 0); |
d4f3574e SS |
1115 | |
1116 | child_ops.to_attach (args, from_tty); | |
1117 | ||
1118 | if (linuxthreads_max) | |
1119 | linuxthreads_attach_pending = 1; | |
1120 | } | |
1121 | ||
1122 | /* Take a program previously attached to and detaches it. | |
1123 | The program resumes execution and will no longer stop | |
1124 | on signals, etc. We'd better not have left any breakpoints | |
1125 | in the program or it'll die when it hits one. For this | |
1126 | to work, it may be necessary for the process to have been | |
1127 | previously attached. It *might* work if the program was | |
1128 | started via the normal ptrace (PTRACE_TRACEME). */ | |
1129 | ||
1130 | static void | |
fba45db2 | 1131 | linuxthreads_detach (char *args, int from_tty) |
d4f3574e SS |
1132 | { |
1133 | if (linuxthreads_max) | |
1134 | { | |
1135 | int i; | |
1136 | int pid; | |
1137 | int off = 0; | |
1138 | target_write_memory (linuxthreads_debug, (char *)&off, sizeof (off)); | |
1139 | ||
1140 | /* Walk through linuxthreads array in order to detach known threads. */ | |
1141 | if (linuxthreads_manager_pid != 0) | |
1142 | { | |
1143 | /* Get rid of all positive zombie breakpoints. */ | |
1144 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) | |
1145 | { | |
1146 | if (linuxthreads_breakpoint_zombie[i].step) | |
1147 | continue; | |
1148 | ||
1149 | pid = linuxthreads_breakpoint_zombie[i].pid; | |
39f77062 | 1150 | if (!linuxthreads_thread_alive (pid_to_ptid (pid))) |
d4f3574e SS |
1151 | continue; |
1152 | ||
39f77062 KB |
1153 | if (linuxthreads_breakpoint_zombie[i].pc |
1154 | != read_pc_pid (pid_to_ptid (pid))) | |
d4f3574e SS |
1155 | continue; |
1156 | ||
1157 | /* Continue in STEP mode until the thread pc has moved or | |
1158 | until SIGTRAP is found on the same PC. */ | |
1159 | if (linuxthreads_find_trap (pid, 0) | |
39f77062 KB |
1160 | && linuxthreads_breakpoint_zombie[i].pc |
1161 | == read_pc_pid (pid_to_ptid (pid))) | |
d4f3574e | 1162 | write_pc_pid (linuxthreads_breakpoint_zombie[i].pc |
39f77062 | 1163 | - DECR_PC_AFTER_BREAK, pid_to_ptid (pid)); |
d4f3574e SS |
1164 | } |
1165 | ||
1166 | /* Detach thread after thread. */ | |
39f77062 | 1167 | inferior_ptid = pid_to_ptid (linuxthreads_manager_pid); |
d4f3574e SS |
1168 | iterate_active_threads (detach_thread, 1); |
1169 | ||
1170 | /* Remove pending SIGTRAP and SIGSTOP */ | |
39f77062 | 1171 | linuxthreads_find_trap (PIDGET (inferior_ptid), 1); |
d4f3574e SS |
1172 | |
1173 | linuxthreads_wait_last = -1; | |
67aaefa2 | 1174 | WSETSTOP (linuxthreads_exit_status, 0); |
d4f3574e SS |
1175 | } |
1176 | ||
1177 | linuxthreads_inferior_pid = 0; | |
1178 | linuxthreads_breakpoint_pid = 0; | |
1179 | linuxthreads_step_pid = 0; | |
1180 | linuxthreads_step_signo = TARGET_SIGNAL_0; | |
1181 | linuxthreads_manager_pid = 0; | |
1182 | linuxthreads_initial_pid = 0; | |
1183 | linuxthreads_attach_pending = 0; | |
1184 | init_thread_list (); /* Destroy thread info */ | |
1185 | } | |
1186 | ||
1187 | child_ops.to_detach (args, from_tty); | |
1188 | ||
1189 | unpush_target (&linuxthreads_ops); | |
1190 | } | |
1191 | ||
1192 | /* Resume execution of process PID. If STEP is nozero, then | |
1193 | just single step it. If SIGNAL is nonzero, restart it with that | |
1194 | signal activated. */ | |
1195 | ||
1196 | static void | |
39f77062 | 1197 | linuxthreads_resume (ptid_t ptid, int step, enum target_signal signo) |
d4f3574e SS |
1198 | { |
1199 | if (!linuxthreads_max || stop_soon_quietly || linuxthreads_manager_pid == 0) | |
ed9a39eb | 1200 | { |
39f77062 | 1201 | child_ops.to_resume (ptid, step, signo); |
ed9a39eb | 1202 | } |
d4f3574e SS |
1203 | else |
1204 | { | |
1205 | int rpid; | |
1206 | if (linuxthreads_inferior_pid) | |
1207 | { | |
1208 | /* Prepare resume of the last thread that hit a breakpoint */ | |
1209 | linuxthreads_breakpoints_inserted = 0; | |
1210 | rpid = linuxthreads_inferior_pid; | |
1211 | linuxthreads_step_signo = signo; | |
1212 | } | |
1213 | else | |
1214 | { | |
1215 | struct cleanup *old_chain = NULL; | |
1216 | int i; | |
1217 | ||
39f77062 | 1218 | if (PIDGET (ptid) < 0) |
d4f3574e | 1219 | { |
39f77062 | 1220 | linuxthreads_step_pid = step ? PIDGET (inferior_ptid) : 0; |
d4f3574e | 1221 | linuxthreads_step_signo = signo; |
39f77062 | 1222 | rpid = PIDGET (inferior_ptid); |
d4f3574e SS |
1223 | } |
1224 | else | |
39f77062 | 1225 | rpid = PIDGET (ptid); |
d4f3574e | 1226 | |
39f77062 | 1227 | if (PIDGET (ptid) < 0 || !step) |
d4f3574e SS |
1228 | { |
1229 | linuxthreads_breakpoints_inserted = 1; | |
1230 | ||
1231 | /* Walk through linuxthreads array in order to resume threads */ | |
39f77062 | 1232 | if (PIDGET (ptid) >= 0 && !ptid_equal (inferior_ptid, ptid)) |
d4f3574e | 1233 | { |
39f77062 KB |
1234 | old_chain = save_inferior_ptid (); |
1235 | inferior_ptid = ptid; | |
d4f3574e SS |
1236 | } |
1237 | ||
1238 | iterate_active_threads (resume_thread, 0); | |
39f77062 | 1239 | if (linuxthreads_manager_pid != PIDGET (inferior_ptid) |
d4f3574e SS |
1240 | && !linuxthreads_pending_status (linuxthreads_manager_pid)) |
1241 | resume_thread (linuxthreads_manager_pid); | |
1242 | } | |
1243 | else | |
1244 | linuxthreads_breakpoints_inserted = 0; | |
1245 | ||
1246 | /* Deal with zombie breakpoint */ | |
1247 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) | |
1248 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) | |
1249 | { | |
39f77062 KB |
1250 | if (linuxthreads_breakpoint_zombie[i].pc |
1251 | != read_pc_pid (pid_to_ptid (rpid))) | |
d4f3574e SS |
1252 | { |
1253 | /* The current pc is out of zombie breakpoint. */ | |
1254 | REMOVE_BREAKPOINT_ZOMBIE(i); | |
1255 | } | |
1256 | break; | |
1257 | } | |
1258 | ||
1259 | if (old_chain != NULL) | |
1260 | do_cleanups (old_chain); | |
1261 | } | |
1262 | ||
1263 | /* Resume initial thread. */ | |
ed9a39eb | 1264 | /* [unles it has a wait event pending] */ |
d4f3574e | 1265 | if (!linuxthreads_pending_status (rpid)) |
ed9a39eb | 1266 | { |
39f77062 | 1267 | child_ops.to_resume (pid_to_ptid (rpid), step, signo); |
ed9a39eb | 1268 | } |
d4f3574e SS |
1269 | } |
1270 | } | |
1271 | ||
ed9a39eb JM |
1272 | /* Abstract out the child_wait functionality. */ |
1273 | int | |
fba45db2 | 1274 | linux_child_wait (int pid, int *rpid, int *status) |
ed9a39eb JM |
1275 | { |
1276 | int save_errno; | |
1277 | ||
1278 | /* Note: inftarg has these inside the loop. */ | |
1279 | set_sigint_trap (); /* Causes SIGINT to be passed on to the | |
1280 | attached process. */ | |
1281 | set_sigio_trap (); | |
1282 | ||
1283 | errno = save_errno = 0; | |
1284 | for (;;) | |
1285 | { | |
1286 | errno = 0; | |
1287 | *rpid = waitpid (pid, status, __WCLONE | WNOHANG); | |
1288 | save_errno = errno; | |
1289 | ||
1290 | if (*rpid > 0) | |
1291 | { | |
1292 | /* Got an event -- break out */ | |
1293 | break; | |
1294 | } | |
1295 | if (errno == EINTR) /* interrupted by signal, try again */ | |
1296 | { | |
1297 | continue; | |
1298 | } | |
1299 | ||
1300 | errno = 0; | |
1301 | *rpid = waitpid (pid, status, WNOHANG); | |
1302 | if (*rpid > 0) | |
1303 | { | |
1304 | /* Got an event -- break out */ | |
1305 | break; | |
1306 | } | |
1307 | if (errno == EINTR) | |
1308 | { | |
1309 | continue; | |
1310 | } | |
1311 | if (errno != 0 && save_errno != 0) | |
1312 | { | |
1313 | break; | |
1314 | } | |
1315 | sigsuspend(&linuxthreads_block_mask); | |
1316 | } | |
1317 | clear_sigio_trap (); | |
1318 | clear_sigint_trap (); | |
1319 | ||
1320 | return errno ? errno : save_errno; | |
1321 | } | |
1322 | ||
1323 | ||
d4f3574e SS |
1324 | /* Wait for any threads to stop. We may have to convert PID from a thread id |
1325 | to a LWP id, and vice versa on the way out. */ | |
1326 | ||
39f77062 KB |
1327 | static ptid_t |
1328 | linuxthreads_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
d4f3574e SS |
1329 | { |
1330 | int status; | |
1331 | int rpid; | |
1332 | int i; | |
1333 | int last; | |
1334 | int *wstatus; | |
39f77062 | 1335 | int pid = PIDGET (ptid); |
d4f3574e SS |
1336 | |
1337 | if (linuxthreads_max && !linuxthreads_breakpoints_inserted) | |
1338 | wstatus = alloca (LINUXTHREAD_NSIG * sizeof (int)); | |
1339 | ||
1340 | /* See if the inferior has chosen values for its signals yet. By | |
1341 | checking for them here, we can be sure we've updated GDB's signal | |
1342 | handling table before the inferior ever gets one of them. (Well, | |
1343 | before we notice, anyway.) */ | |
1344 | check_all_signal_numbers (); | |
1345 | ||
1346 | for (;;) | |
1347 | { | |
1348 | if (!linuxthreads_max) | |
1349 | rpid = 0; | |
1350 | else if (!linuxthreads_breakpoints_inserted) | |
1351 | { | |
1352 | if (linuxthreads_inferior_pid) | |
1353 | pid = linuxthreads_inferior_pid; | |
1354 | else if (pid < 0) | |
39f77062 | 1355 | pid = PIDGET (inferior_ptid); |
d4f3574e SS |
1356 | last = rpid = 0; |
1357 | } | |
1358 | else if (pid < 0 && linuxthreads_wait_last >= 0) | |
1359 | { | |
1360 | status = linuxthreads_wait_status[linuxthreads_wait_last]; | |
1361 | rpid = linuxthreads_wait_pid[linuxthreads_wait_last--]; | |
1362 | } | |
1363 | else if (pid > 0 && linuxthreads_pending_status (pid)) | |
1364 | { | |
1365 | for (i = linuxthreads_wait_last; i >= 0; i--) | |
1366 | if (linuxthreads_wait_pid[i] == pid) | |
1367 | break; | |
1368 | if (i < 0) | |
1369 | rpid = 0; | |
1370 | else | |
1371 | { | |
1372 | status = linuxthreads_wait_status[i]; | |
1373 | rpid = pid; | |
1374 | if (i < linuxthreads_wait_last) | |
1375 | { | |
1376 | linuxthreads_wait_status[i] = | |
1377 | linuxthreads_wait_status[linuxthreads_wait_last]; | |
1378 | linuxthreads_wait_pid[i] = | |
1379 | linuxthreads_wait_pid[linuxthreads_wait_last]; | |
1380 | } | |
1381 | linuxthreads_wait_last--; | |
1382 | } | |
1383 | } | |
1384 | else | |
1385 | rpid = 0; | |
1386 | ||
1387 | if (rpid == 0) | |
1388 | { | |
1389 | int save_errno; | |
d4f3574e | 1390 | |
ed9a39eb | 1391 | save_errno = linux_child_wait (pid, &rpid, &status); |
d4f3574e SS |
1392 | |
1393 | if (rpid == -1) | |
1394 | { | |
1395 | if (WIFEXITED(linuxthreads_exit_status)) | |
1396 | { | |
1397 | store_waitstatus (ourstatus, linuxthreads_exit_status); | |
39f77062 | 1398 | return inferior_ptid; |
d4f3574e SS |
1399 | } |
1400 | else | |
1401 | { | |
1402 | fprintf_unfiltered | |
1403 | (gdb_stderr, "Child process unexpectedly missing: %s.\n", | |
1404 | safe_strerror (save_errno)); | |
1405 | /* Claim it exited with unknown signal. */ | |
1406 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
1407 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
39f77062 | 1408 | return pid_to_ptid (-1); |
d4f3574e SS |
1409 | } |
1410 | } | |
1411 | ||
ed9a39eb JM |
1412 | /* We have now gotten a new event from waitpid above. */ |
1413 | ||
1414 | /* Signals arrive in any order. So get all signals until | |
1415 | SIGTRAP and resend previous ones to be held after. */ | |
d4f3574e SS |
1416 | if (linuxthreads_max |
1417 | && !linuxthreads_breakpoints_inserted | |
1418 | && WIFSTOPPED(status)) | |
1419 | if (WSTOPSIG(status) == SIGTRAP) | |
1420 | { | |
1421 | while (--last >= 0) | |
ed9a39eb JM |
1422 | { |
1423 | kill (rpid, WSTOPSIG(wstatus[last])); | |
1424 | } | |
d4f3574e SS |
1425 | |
1426 | /* insert negative zombie breakpoint */ | |
1427 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) | |
1428 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) | |
1429 | break; | |
1430 | if (i > linuxthreads_breakpoint_last) | |
1431 | { | |
1432 | linuxthreads_breakpoint_zombie[i].pid = rpid; | |
1433 | linuxthreads_breakpoint_last++; | |
1434 | } | |
39f77062 KB |
1435 | linuxthreads_breakpoint_zombie[i].pc |
1436 | = read_pc_pid (pid_to_ptid (rpid)); | |
d4f3574e SS |
1437 | linuxthreads_breakpoint_zombie[i].step = 1; |
1438 | } | |
1439 | else | |
1440 | { | |
1441 | if (WSTOPSIG(status) != SIGSTOP) | |
1442 | { | |
1443 | for (i = 0; i < last; i++) | |
1444 | if (wstatus[i] == status) | |
1445 | break; | |
1446 | if (i >= last) | |
ed9a39eb JM |
1447 | { |
1448 | wstatus[last++] = status; | |
1449 | } | |
d4f3574e | 1450 | } |
39f77062 | 1451 | child_resume (pid_to_ptid (rpid), 1, TARGET_SIGNAL_0); |
d4f3574e SS |
1452 | continue; |
1453 | } | |
1454 | if (linuxthreads_inferior_pid) | |
1455 | linuxthreads_inferior_pid = 0; | |
1456 | } | |
1457 | ||
1458 | if (linuxthreads_max && !stop_soon_quietly) | |
1459 | { | |
1460 | if (linuxthreads_max | |
1461 | && WIFSTOPPED(status) | |
1462 | && WSTOPSIG(status) == SIGSTOP) | |
1463 | { | |
1464 | /* Skip SIGSTOP signals. */ | |
1465 | if (!linuxthreads_pending_status (rpid)) | |
5c44784c JM |
1466 | { |
1467 | if (linuxthreads_step_pid == rpid) | |
ed9a39eb | 1468 | { |
39f77062 KB |
1469 | child_resume (pid_to_ptid (rpid), 1, |
1470 | linuxthreads_step_signo); | |
ed9a39eb | 1471 | } |
5c44784c | 1472 | else |
ed9a39eb | 1473 | { |
39f77062 | 1474 | child_resume (pid_to_ptid (rpid), 0, TARGET_SIGNAL_0); |
ed9a39eb | 1475 | } |
5c44784c | 1476 | } |
d4f3574e SS |
1477 | continue; |
1478 | } | |
1479 | ||
1480 | /* Do no report exit status of cloned threads. */ | |
1481 | if (WIFEXITED(status)) | |
1482 | { | |
1483 | if (rpid == linuxthreads_initial_pid) | |
1484 | linuxthreads_exit_status = status; | |
1485 | ||
1486 | /* Remove any zombie breakpoint. */ | |
1487 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) | |
1488 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) | |
1489 | { | |
1490 | REMOVE_BREAKPOINT_ZOMBIE(i); | |
1491 | break; | |
1492 | } | |
1493 | if (pid > 0) | |
1494 | pid = -1; | |
1495 | continue; | |
1496 | } | |
1497 | ||
1498 | /* Deal with zombie breakpoint */ | |
1499 | for (i = 0; i <= linuxthreads_breakpoint_last; i++) | |
1500 | if (linuxthreads_breakpoint_zombie[i].pid == rpid) | |
1501 | break; | |
1502 | ||
1503 | if (i <= linuxthreads_breakpoint_last) | |
1504 | { | |
1505 | /* There is a potential zombie breakpoint */ | |
1506 | if (WIFEXITED(status) | |
39f77062 KB |
1507 | || linuxthreads_breakpoint_zombie[i].pc |
1508 | != read_pc_pid (pid_to_ptid (rpid))) | |
d4f3574e SS |
1509 | { |
1510 | /* The current pc is out of zombie breakpoint. */ | |
1511 | REMOVE_BREAKPOINT_ZOMBIE(i); | |
1512 | } | |
1513 | else if (!linuxthreads_breakpoint_zombie[i].step | |
1514 | && WIFSTOPPED(status) && WSTOPSIG(status) == SIGTRAP) | |
1515 | { | |
1516 | /* This is a real one ==> decrement PC and restart. */ | |
1517 | write_pc_pid (linuxthreads_breakpoint_zombie[i].pc | |
39f77062 | 1518 | - DECR_PC_AFTER_BREAK, pid_to_ptid (rpid)); |
d4f3574e | 1519 | if (linuxthreads_step_pid == rpid) |
ed9a39eb | 1520 | { |
39f77062 | 1521 | child_resume (pid_to_ptid (rpid), 1, linuxthreads_step_signo); |
ed9a39eb | 1522 | } |
d4f3574e | 1523 | else |
ed9a39eb | 1524 | { |
39f77062 | 1525 | child_resume (pid_to_ptid (rpid), 0, TARGET_SIGNAL_0); |
ed9a39eb | 1526 | } |
d4f3574e SS |
1527 | continue; |
1528 | } | |
1529 | } | |
1530 | ||
1531 | /* Walk through linuxthreads array in order to stop them */ | |
1532 | if (linuxthreads_breakpoints_inserted) | |
1533 | update_stop_threads (rpid); | |
1534 | ||
1535 | } | |
39f77062 | 1536 | else if (rpid != PIDGET (inferior_ptid)) |
d4f3574e SS |
1537 | continue; |
1538 | ||
1539 | store_waitstatus (ourstatus, status); | |
1540 | ||
1541 | if (linuxthreads_attach_pending && !stop_soon_quietly) | |
1542 | { | |
1543 | int on = 1; | |
ed9a39eb JM |
1544 | if (!using_thread_db) |
1545 | { | |
1546 | target_write_memory (linuxthreads_debug, | |
1547 | (char *) &on, sizeof (on)); | |
1548 | update_stop_threads (rpid); | |
1549 | } | |
d4f3574e SS |
1550 | linuxthreads_attach_pending = 0; |
1551 | } | |
1552 | ||
1553 | if (linuxthreads_breakpoints_inserted | |
1554 | && WIFSTOPPED(status) | |
1555 | && WSTOPSIG(status) == SIGTRAP) | |
1556 | linuxthreads_breakpoint_pid = rpid; | |
1557 | else if (linuxthreads_breakpoint_pid) | |
1558 | linuxthreads_breakpoint_pid = 0; | |
1559 | ||
39f77062 | 1560 | return pid_to_ptid (rpid); |
d4f3574e SS |
1561 | } |
1562 | } | |
1563 | ||
1564 | /* Fork an inferior process, and start debugging it with ptrace. */ | |
1565 | ||
1566 | static void | |
fba45db2 | 1567 | linuxthreads_create_inferior (char *exec_file, char *allargs, char **env) |
d4f3574e SS |
1568 | { |
1569 | if (!exec_file && !exec_bfd) | |
1570 | { | |
1571 | error ("No executable file specified.\n\ | |
1572 | Use the \"file\" or \"exec-file\" command."); | |
1573 | return; | |
1574 | } | |
1575 | ||
1576 | push_target (&linuxthreads_ops); | |
1577 | linuxthreads_breakpoints_inserted = 1; | |
1578 | linuxthreads_breakpoint_last = -1; | |
1579 | linuxthreads_wait_last = -1; | |
67aaefa2 | 1580 | WSETSTOP (linuxthreads_exit_status, 0); |
d4f3574e SS |
1581 | |
1582 | if (linuxthreads_max) | |
1583 | linuxthreads_attach_pending = 1; | |
1584 | ||
1585 | child_ops.to_create_inferior (exec_file, allargs, env); | |
1586 | } | |
1587 | ||
ed9a39eb | 1588 | void |
fba45db2 | 1589 | linuxthreads_discard_global_state (void) |
ed9a39eb JM |
1590 | { |
1591 | linuxthreads_inferior_pid = 0; | |
1592 | linuxthreads_breakpoint_pid = 0; | |
1593 | linuxthreads_step_pid = 0; | |
1594 | linuxthreads_step_signo = TARGET_SIGNAL_0; | |
1595 | linuxthreads_manager_pid = 0; | |
1596 | linuxthreads_initial_pid = 0; | |
1597 | linuxthreads_attach_pending = 0; | |
1598 | linuxthreads_max = 0; | |
1599 | } | |
1600 | ||
d4f3574e SS |
1601 | /* Clean up after the inferior dies. */ |
1602 | ||
1603 | static void | |
fba45db2 | 1604 | linuxthreads_mourn_inferior (void) |
d4f3574e SS |
1605 | { |
1606 | if (linuxthreads_max) | |
1607 | { | |
1608 | int off = 0; | |
1609 | target_write_memory (linuxthreads_debug, (char *)&off, sizeof (off)); | |
1610 | ||
ed9a39eb | 1611 | linuxthreads_discard_global_state (); |
d4f3574e SS |
1612 | init_thread_list(); /* Destroy thread info */ |
1613 | } | |
1614 | ||
1615 | child_ops.to_mourn_inferior (); | |
1616 | ||
1617 | unpush_target (&linuxthreads_ops); | |
1618 | } | |
1619 | ||
1620 | /* Kill the inferior process */ | |
1621 | ||
1622 | static void | |
fba45db2 | 1623 | linuxthreads_kill (void) |
d4f3574e SS |
1624 | { |
1625 | int rpid; | |
1626 | int status; | |
1627 | ||
39f77062 | 1628 | if (PIDGET (inferior_ptid) == 0) |
d4f3574e SS |
1629 | return; |
1630 | ||
1631 | if (linuxthreads_max && linuxthreads_manager_pid != 0) | |
1632 | { | |
1633 | /* Remove all threads status. */ | |
39f77062 | 1634 | inferior_ptid = pid_to_ptid (linuxthreads_manager_pid); |
d4f3574e SS |
1635 | iterate_active_threads (kill_thread, 1); |
1636 | } | |
1637 | ||
39f77062 | 1638 | kill_thread (PIDGET (inferior_ptid)); |
d4f3574e SS |
1639 | |
1640 | #if 0 | |
1641 | /* doing_quit_force solves a real problem, but I think a properly | |
1642 | placed call to catch_errors would do the trick much more cleanly. */ | |
1643 | if (doing_quit_force >= 0) | |
1644 | { | |
1645 | if (linuxthreads_max && linuxthreads_manager_pid != 0) | |
1646 | { | |
1647 | /* Wait for thread to complete */ | |
1648 | while ((rpid = waitpid (-1, &status, __WCLONE)) > 0) | |
1649 | if (!WIFEXITED(status)) | |
1650 | kill_thread (rpid); | |
1651 | ||
1652 | while ((rpid = waitpid (-1, &status, 0)) > 0) | |
1653 | if (!WIFEXITED(status)) | |
1654 | kill_thread (rpid); | |
1655 | } | |
1656 | else | |
39f77062 | 1657 | while ((rpid = waitpid (PIDGET (inferior_ptid), &status, 0)) > 0) |
d4f3574e | 1658 | if (!WIFEXITED(status)) |
39f77062 | 1659 | ptrace (PT_KILL, PIDGET (inferior_ptid), (PTRACE_ARG3_TYPE) 0, 0); |
d4f3574e SS |
1660 | } |
1661 | #endif | |
1662 | ||
1663 | /* Wait for all threads. */ | |
1664 | do | |
ed9a39eb JM |
1665 | { |
1666 | rpid = waitpid (-1, &status, __WCLONE | WNOHANG); | |
1667 | } | |
d4f3574e | 1668 | while (rpid > 0 || errno == EINTR); |
ed9a39eb | 1669 | /* FIXME: should no longer need to handle EINTR here. */ |
d4f3574e SS |
1670 | |
1671 | do | |
ed9a39eb JM |
1672 | { |
1673 | rpid = waitpid (-1, &status, WNOHANG); | |
1674 | } | |
d4f3574e | 1675 | while (rpid > 0 || errno == EINTR); |
ed9a39eb | 1676 | /* FIXME: should no longer need to handle EINTR here. */ |
d4f3574e SS |
1677 | |
1678 | linuxthreads_mourn_inferior (); | |
1679 | } | |
1680 | ||
1681 | /* Insert a breakpoint */ | |
1682 | ||
1683 | static int | |
fba45db2 | 1684 | linuxthreads_insert_breakpoint (CORE_ADDR addr, char *contents_cache) |
d4f3574e SS |
1685 | { |
1686 | if (linuxthreads_max && linuxthreads_manager_pid != 0) | |
1687 | { | |
1688 | linuxthreads_breakpoint_addr = addr; | |
1689 | iterate_active_threads (insert_breakpoint, 1); | |
1690 | insert_breakpoint (linuxthreads_manager_pid); | |
1691 | } | |
1692 | ||
1693 | return child_ops.to_insert_breakpoint (addr, contents_cache); | |
1694 | } | |
1695 | ||
1696 | /* Remove a breakpoint */ | |
1697 | ||
1698 | static int | |
fba45db2 | 1699 | linuxthreads_remove_breakpoint (CORE_ADDR addr, char *contents_cache) |
d4f3574e SS |
1700 | { |
1701 | if (linuxthreads_max && linuxthreads_manager_pid != 0) | |
1702 | { | |
1703 | linuxthreads_breakpoint_addr = addr; | |
1704 | iterate_active_threads (remove_breakpoint, 1); | |
1705 | remove_breakpoint (linuxthreads_manager_pid); | |
1706 | } | |
1707 | ||
1708 | return child_ops.to_remove_breakpoint (addr, contents_cache); | |
1709 | } | |
1710 | ||
1711 | /* Mark our target-struct as eligible for stray "run" and "attach" commands. */ | |
1712 | ||
1713 | static int | |
fba45db2 | 1714 | linuxthreads_can_run (void) |
d4f3574e SS |
1715 | { |
1716 | return child_suppress_run; | |
1717 | } | |
ed9a39eb | 1718 | |
d4f3574e SS |
1719 | \f |
1720 | static void | |
fba45db2 | 1721 | init_linuxthreads_ops (void) |
d4f3574e SS |
1722 | { |
1723 | linuxthreads_ops.to_shortname = "linuxthreads"; | |
1724 | linuxthreads_ops.to_longname = "LINUX threads and pthread."; | |
1725 | linuxthreads_ops.to_doc = "LINUX threads and pthread support."; | |
1726 | linuxthreads_ops.to_attach = linuxthreads_attach; | |
1727 | linuxthreads_ops.to_detach = linuxthreads_detach; | |
1728 | linuxthreads_ops.to_resume = linuxthreads_resume; | |
1729 | linuxthreads_ops.to_wait = linuxthreads_wait; | |
1730 | linuxthreads_ops.to_kill = linuxthreads_kill; | |
1731 | linuxthreads_ops.to_can_run = linuxthreads_can_run; | |
1732 | linuxthreads_ops.to_stratum = thread_stratum; | |
1733 | linuxthreads_ops.to_insert_breakpoint = linuxthreads_insert_breakpoint; | |
1734 | linuxthreads_ops.to_remove_breakpoint = linuxthreads_remove_breakpoint; | |
1735 | linuxthreads_ops.to_create_inferior = linuxthreads_create_inferior; | |
1736 | linuxthreads_ops.to_mourn_inferior = linuxthreads_mourn_inferior; | |
1737 | linuxthreads_ops.to_thread_alive = linuxthreads_thread_alive; | |
ed9a39eb | 1738 | linuxthreads_ops.to_pid_to_str = linuxthreads_pid_to_str; |
d4f3574e SS |
1739 | linuxthreads_ops.to_magic = OPS_MAGIC; |
1740 | } | |
1741 | ||
1742 | void | |
fba45db2 | 1743 | _initialize_linuxthreads (void) |
d4f3574e SS |
1744 | { |
1745 | struct sigaction sact; | |
ed9a39eb | 1746 | sigset_t linuxthreads_wait_mask; /* sigset with SIGCHLD */ |
d4f3574e SS |
1747 | |
1748 | init_linuxthreads_ops (); | |
1749 | add_target (&linuxthreads_ops); | |
1750 | child_suppress_run = 1; | |
1751 | ||
11cf8741 JM |
1752 | /* Hook onto the "new_objfile" event. |
1753 | * If someone else is already hooked onto the event, | |
1754 | * then make sure he will be called after we are. | |
1755 | */ | |
1756 | target_new_objfile_chain = target_new_objfile_hook; | |
1757 | target_new_objfile_hook = linuxthreads_new_objfile; | |
1758 | ||
d4f3574e SS |
1759 | /* Attach SIGCHLD handler */ |
1760 | sact.sa_handler = sigchld_handler; | |
1761 | sigemptyset (&sact.sa_mask); | |
1762 | sact.sa_flags = 0; | |
1763 | sigaction (SIGCHLD, &sact, NULL); | |
1764 | ||
1765 | /* initialize SIGCHLD mask */ | |
1766 | sigemptyset (&linuxthreads_wait_mask); | |
1767 | sigaddset (&linuxthreads_wait_mask, SIGCHLD); | |
ed9a39eb JM |
1768 | |
1769 | /* Use SIG_BLOCK to block receipt of SIGCHLD. | |
1770 | The block_mask will allow us to wait for this signal explicitly. */ | |
1771 | sigprocmask(SIG_BLOCK, | |
1772 | &linuxthreads_wait_mask, | |
1773 | &linuxthreads_block_mask); | |
0fda6bd2 JM |
1774 | /* Make sure that linuxthreads_block_mask is not blocking SIGCHLD */ |
1775 | sigdelset (&linuxthreads_block_mask, SIGCHLD); | |
d4f3574e | 1776 | } |