Commit | Line | Data |
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2c4a536d | 1 | /* Low-level child interface to ptrace. |
5bf970f9 | 2 | |
6aba47ca | 3 | Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, |
0fb0cc75 | 4 | 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2008, 2009 |
8785ced0 | 5 | Free Software Foundation, Inc. |
5bf970f9 AC |
6 | |
7 | This file is part of GDB. | |
8 | ||
9 | This program is free software; you can redistribute it and/or modify | |
10 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 11 | the Free Software Foundation; either version 3 of the License, or |
5bf970f9 AC |
12 | (at your option) any later version. |
13 | ||
14 | This program is distributed in the hope that it will be useful, | |
15 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | GNU General Public License for more details. | |
18 | ||
19 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 20 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
5bf970f9 AC |
21 | |
22 | #include "defs.h" | |
5bf970f9 | 23 | #include "command.h" |
2c4a536d MK |
24 | #include "inferior.h" |
25 | #include "inflow.h" | |
5bf970f9 | 26 | #include "gdbcore.h" |
8785ced0 | 27 | #include "regcache.h" |
5bf970f9 | 28 | |
8785ced0 | 29 | #include "gdb_assert.h" |
2c4a536d MK |
30 | #include "gdb_string.h" |
31 | #include "gdb_ptrace.h" | |
34a17005 | 32 | #include "gdb_wait.h" |
5bf970f9 AC |
33 | #include <signal.h> |
34 | ||
2c4a536d | 35 | #include "inf-child.h" |
af990527 | 36 | #include "gdbthread.h" |
2c4a536d | 37 | |
c7c14b96 MK |
38 | \f |
39 | ||
735f54b4 MK |
40 | #ifdef PT_GET_PROCESS_STATE |
41 | ||
42 | static int | |
ee057212 | 43 | inf_ptrace_follow_fork (struct target_ops *ops, int follow_child) |
735f54b4 MK |
44 | { |
45 | pid_t pid, fpid; | |
46 | ptrace_state_t pe; | |
4e1c45ea | 47 | struct thread_info *last_tp = NULL; |
735f54b4 MK |
48 | |
49 | /* FIXME: kettenis/20050720: This stuff should really be passed as | |
50 | an argument by our caller. */ | |
51 | { | |
52 | ptid_t ptid; | |
53 | struct target_waitstatus status; | |
54 | ||
55 | get_last_target_status (&ptid, &status); | |
56 | gdb_assert (status.kind == TARGET_WAITKIND_FORKED); | |
57 | ||
58 | pid = ptid_get_pid (ptid); | |
4e1c45ea | 59 | last_tp = find_thread_pid (ptid); |
735f54b4 MK |
60 | } |
61 | ||
62 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
63 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
64 | perror_with_name (("ptrace")); | |
65 | ||
66 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
67 | fpid = pe.pe_other_pid; | |
68 | ||
69 | if (follow_child) | |
70 | { | |
4e1c45ea PA |
71 | /* Copy user stepping state to the new inferior thread. */ |
72 | struct breakpoint *step_resume_breakpoint = last_tp->step_resume_breakpoint; | |
73 | CORE_ADDR step_range_start = last_tp->step_range_start; | |
74 | CORE_ADDR step_range_end = last_tp->step_range_end; | |
75 | struct frame_id step_frame_id = last_tp->step_frame_id; | |
735f54b4 | 76 | |
4e1c45ea PA |
77 | struct thread_info *tp; |
78 | ||
79 | /* Otherwise, deleting the parent would get rid of this | |
80 | breakpoint. */ | |
81 | last_tp->step_resume_breakpoint = NULL; | |
82 | ||
83 | /* Before detaching from the parent, remove all breakpoints from | |
84 | it. */ | |
85 | detach_breakpoints (pid); | |
735f54b4 MK |
86 | |
87 | if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
88 | perror_with_name (("ptrace")); | |
4e1c45ea | 89 | |
7f9f62ba PA |
90 | /* Switch inferior_ptid out of the parent's way. */ |
91 | inferior_ptid = pid_to_ptid (fpid); | |
92 | ||
4e1c45ea | 93 | /* Delete the parent. */ |
7f9f62ba | 94 | detach_inferior (pid); |
4e1c45ea PA |
95 | |
96 | /* Add the child. */ | |
7f9f62ba | 97 | add_inferior (fpid); |
4e1c45ea PA |
98 | tp = add_thread_silent (inferior_ptid); |
99 | ||
100 | tp->step_resume_breakpoint = step_resume_breakpoint; | |
101 | tp->step_range_start = step_range_start; | |
102 | tp->step_range_end = step_range_end; | |
103 | tp->step_frame_id = step_frame_id; | |
104 | ||
105 | /* Reset breakpoints in the child as appropriate. */ | |
106 | follow_inferior_reset_breakpoints (); | |
735f54b4 MK |
107 | } |
108 | else | |
109 | { | |
110 | inferior_ptid = pid_to_ptid (pid); | |
111 | detach_breakpoints (fpid); | |
112 | ||
113 | if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
114 | perror_with_name (("ptrace")); | |
7f9f62ba | 115 | detach_inferior (pid); |
735f54b4 MK |
116 | } |
117 | ||
118 | return 0; | |
119 | } | |
120 | ||
121 | #endif /* PT_GET_PROCESS_STATE */ | |
122 | \f | |
123 | ||
4b8a1a28 | 124 | /* Prepare to be traced. */ |
5bf970f9 AC |
125 | |
126 | static void | |
c7c14b96 | 127 | inf_ptrace_me (void) |
5bf970f9 | 128 | { |
c7c14b96 | 129 | /* "Trace me, Dr. Memory!" */ |
4b8a1a28 | 130 | ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0); |
5bf970f9 AC |
131 | } |
132 | ||
136d6dae VP |
133 | /* Start a new inferior Unix child process. EXEC_FILE is the file to |
134 | run, ALLARGS is a string containing the arguments to the program. | |
135 | ENV is the environment vector to pass. If FROM_TTY is non-zero, be | |
136 | chatty about it. */ | |
5bf970f9 AC |
137 | |
138 | static void | |
136d6dae VP |
139 | inf_ptrace_create_inferior (struct target_ops *ops, |
140 | char *exec_file, char *allargs, char **env, | |
141 | int from_tty) | |
5bf970f9 | 142 | { |
136d6dae VP |
143 | int pid; |
144 | ||
145 | pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL, | |
146 | NULL, NULL); | |
147 | ||
148 | push_target (ops); | |
5bf970f9 | 149 | |
c7c14b96 MK |
150 | /* On some targets, there must be some explicit synchronization |
151 | between the parent and child processes after the debugger | |
152 | forks, and before the child execs the debuggee program. This | |
153 | call basically gives permission for the child to exec. */ | |
5bf970f9 | 154 | |
c7c14b96 | 155 | target_acknowledge_created_inferior (pid); |
5bf970f9 | 156 | |
c7c14b96 MK |
157 | /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will |
158 | be 1 or 2 depending on whether we're starting without or with a | |
159 | shell. */ | |
160 | startup_inferior (START_INFERIOR_TRAPS_EXPECTED); | |
161 | ||
162 | /* On some targets, there must be some explicit actions taken after | |
163 | the inferior has been started up. */ | |
164 | target_post_startup_inferior (pid_to_ptid (pid)); | |
5bf970f9 AC |
165 | } |
166 | ||
e4ef629d MK |
167 | #ifdef PT_GET_PROCESS_STATE |
168 | ||
169 | static void | |
170 | inf_ptrace_post_startup_inferior (ptid_t pid) | |
171 | { | |
172 | ptrace_event_t pe; | |
173 | ||
174 | /* Set the initial event mask. */ | |
175 | memset (&pe, 0, sizeof pe); | |
176 | pe.pe_set_event |= PTRACE_FORK; | |
177 | if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid), | |
178 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
179 | perror_with_name (("ptrace")); | |
180 | } | |
181 | ||
182 | #endif | |
183 | ||
4b8a1a28 MK |
184 | /* Clean up a rotting corpse of an inferior after it died. */ |
185 | ||
c7c14b96 | 186 | static void |
136d6dae | 187 | inf_ptrace_mourn_inferior (struct target_ops *ops) |
5bf970f9 | 188 | { |
4b8a1a28 MK |
189 | int status; |
190 | ||
191 | /* Wait just one more time to collect the inferior's exit status. | |
f010475d | 192 | Do not check whether this succeeds though, since we may be |
4b8a1a28 | 193 | dealing with a process that we attached to. Such a process will |
3d450bdd | 194 | only report its exit status to its original parent. */ |
4b8a1a28 MK |
195 | waitpid (ptid_get_pid (inferior_ptid), &status, 0); |
196 | ||
136d6dae | 197 | unpush_target (ops); |
c7c14b96 | 198 | generic_mourn_inferior (); |
5bf970f9 AC |
199 | } |
200 | ||
4b8a1a28 MK |
201 | /* Attach to the process specified by ARGS. If FROM_TTY is non-zero, |
202 | be chatty about it. */ | |
5bf970f9 AC |
203 | |
204 | static void | |
136d6dae | 205 | inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty) |
5bf970f9 AC |
206 | { |
207 | char *exec_file; | |
4b8a1a28 | 208 | pid_t pid; |
5bf970f9 | 209 | char *dummy; |
181e7f93 | 210 | struct inferior *inf; |
5bf970f9 AC |
211 | |
212 | if (!args) | |
e2e0b3e5 | 213 | error_no_arg (_("process-id to attach")); |
5bf970f9 AC |
214 | |
215 | dummy = args; | |
216 | pid = strtol (args, &dummy, 0); | |
f6ffd89b | 217 | /* Some targets don't set errno on errors, grrr! */ |
6e1e94ea | 218 | if (pid == 0 && args == dummy) |
8a3fe4f8 | 219 | error (_("Illegal process-id: %s."), args); |
5bf970f9 | 220 | |
f6ffd89b | 221 | if (pid == getpid ()) /* Trying to masturbate? */ |
8a3fe4f8 | 222 | error (_("I refuse to debug myself!")); |
5bf970f9 AC |
223 | |
224 | if (from_tty) | |
225 | { | |
4b8a1a28 | 226 | exec_file = get_exec_file (0); |
5bf970f9 AC |
227 | |
228 | if (exec_file) | |
a3f17187 | 229 | printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, |
5bf970f9 AC |
230 | target_pid_to_str (pid_to_ptid (pid))); |
231 | else | |
a3f17187 | 232 | printf_unfiltered (_("Attaching to %s\n"), |
5bf970f9 AC |
233 | target_pid_to_str (pid_to_ptid (pid))); |
234 | ||
235 | gdb_flush (gdb_stdout); | |
236 | } | |
237 | ||
6e1e94ea MK |
238 | #ifdef PT_ATTACH |
239 | errno = 0; | |
4b8a1a28 | 240 | ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0); |
6e1e94ea | 241 | if (errno != 0) |
e2e0b3e5 | 242 | perror_with_name (("ptrace")); |
6e1e94ea | 243 | #else |
8a3fe4f8 | 244 | error (_("This system does not support attaching to a process")); |
6e1e94ea | 245 | #endif |
5bf970f9 AC |
246 | |
247 | inferior_ptid = pid_to_ptid (pid); | |
af990527 | 248 | |
181e7f93 PA |
249 | inf = add_inferior (pid); |
250 | inf->attach_flag = 1; | |
7f9f62ba | 251 | |
af990527 PA |
252 | /* Always add a main thread. If some target extends the ptrace |
253 | target, it should decorate the ptid later with more info. */ | |
254 | add_thread_silent (inferior_ptid); | |
255 | ||
136d6dae | 256 | push_target(ops); |
5bf970f9 AC |
257 | } |
258 | ||
e4ef629d MK |
259 | #ifdef PT_GET_PROCESS_STATE |
260 | ||
261 | void | |
262 | inf_ptrace_post_attach (int pid) | |
263 | { | |
264 | ptrace_event_t pe; | |
265 | ||
266 | /* Set the initial event mask. */ | |
267 | memset (&pe, 0, sizeof pe); | |
268 | pe.pe_set_event |= PTRACE_FORK; | |
269 | if (ptrace (PT_SET_EVENT_MASK, pid, | |
270 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
271 | perror_with_name (("ptrace")); | |
272 | } | |
273 | ||
274 | #endif | |
275 | ||
4b8a1a28 | 276 | /* Detach from the inferior, optionally passing it the signal |
f010475d | 277 | specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ |
5bf970f9 AC |
278 | |
279 | static void | |
136d6dae | 280 | inf_ptrace_detach (struct target_ops *ops, char *args, int from_tty) |
5bf970f9 | 281 | { |
4b8a1a28 | 282 | pid_t pid = ptid_get_pid (inferior_ptid); |
6e1e94ea | 283 | int sig = 0; |
5bf970f9 AC |
284 | |
285 | if (from_tty) | |
286 | { | |
287 | char *exec_file = get_exec_file (0); | |
288 | if (exec_file == 0) | |
289 | exec_file = ""; | |
a3f17187 | 290 | printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, |
5bf970f9 AC |
291 | target_pid_to_str (pid_to_ptid (pid))); |
292 | gdb_flush (gdb_stdout); | |
293 | } | |
294 | if (args) | |
6e1e94ea | 295 | sig = atoi (args); |
5bf970f9 | 296 | |
6e1e94ea | 297 | #ifdef PT_DETACH |
4b8a1a28 | 298 | /* We'd better not have left any breakpoints in the program or it'll |
f010475d | 299 | die when it hits one. Also note that this may only work if we |
4b8a1a28 MK |
300 | previously attached to the inferior. It *might* work if we |
301 | started the process ourselves. */ | |
6e1e94ea | 302 | errno = 0; |
4b8a1a28 | 303 | ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig); |
6e1e94ea | 304 | if (errno != 0) |
e2e0b3e5 | 305 | perror_with_name (("ptrace")); |
6e1e94ea | 306 | #else |
8a3fe4f8 | 307 | error (_("This system does not support detaching from a process")); |
6e1e94ea | 308 | #endif |
5bf970f9 AC |
309 | |
310 | inferior_ptid = null_ptid; | |
7f9f62ba | 311 | detach_inferior (pid); |
7a7d3353 PA |
312 | |
313 | if (!have_inferiors ()) | |
314 | unpush_target (ops); | |
5bf970f9 AC |
315 | } |
316 | ||
4b8a1a28 MK |
317 | /* Kill the inferior. */ |
318 | ||
5bf970f9 | 319 | static void |
4b8a1a28 | 320 | inf_ptrace_kill (void) |
5bf970f9 | 321 | { |
4b8a1a28 | 322 | pid_t pid = ptid_get_pid (inferior_ptid); |
c7c14b96 | 323 | int status; |
c7c14b96 MK |
324 | |
325 | if (pid == 0) | |
326 | return; | |
327 | ||
4b8a1a28 MK |
328 | ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0); |
329 | waitpid (pid, &status, 0); | |
330 | ||
c7c14b96 | 331 | target_mourn_inferior (); |
5bf970f9 AC |
332 | } |
333 | ||
4b8a1a28 | 334 | /* Stop the inferior. */ |
c7c14b96 | 335 | |
5bf970f9 | 336 | static void |
94cc34af | 337 | inf_ptrace_stop (ptid_t ptid) |
5bf970f9 | 338 | { |
4b8a1a28 MK |
339 | /* Send a SIGINT to the process group. This acts just like the user |
340 | typed a ^C on the controlling terminal. Note that using a | |
341 | negative process number in kill() is a System V-ism. The proper | |
342 | BSD interface is killpg(). However, all modern BSDs support the | |
343 | System V interface too. */ | |
c7c14b96 | 344 | kill (-inferior_process_group, SIGINT); |
5bf970f9 AC |
345 | } |
346 | ||
4b8a1a28 MK |
347 | /* Resume execution of thread PTID, or all threads if PTID is -1. If |
348 | STEP is nonzero, single-step it. If SIGNAL is nonzero, give it | |
349 | that signal. */ | |
5bf970f9 AC |
350 | |
351 | static void | |
c7c14b96 | 352 | inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal) |
5bf970f9 | 353 | { |
4b8a1a28 | 354 | pid_t pid = ptid_get_pid (ptid); |
c7c14b96 | 355 | int request = PT_CONTINUE; |
c7c14b96 MK |
356 | |
357 | if (pid == -1) | |
4b8a1a28 MK |
358 | /* Resume all threads. Traditionally ptrace() only supports |
359 | single-threaded processes, so simply resume the inferior. */ | |
360 | pid = ptid_get_pid (inferior_ptid); | |
c7c14b96 MK |
361 | |
362 | if (step) | |
363 | { | |
364 | /* If this system does not support PT_STEP, a higher level | |
365 | function will have called single_step() to transmute the step | |
366 | request into a continue request (by setting breakpoints on | |
367 | all possible successor instructions), so we don't have to | |
368 | worry about that here. */ | |
369 | request = PT_STEP; | |
370 | } | |
371 | ||
372 | /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from | |
373 | where it was. If GDB wanted it to start some other way, we have | |
4b8a1a28 | 374 | already written a new program counter value to the child. */ |
c7c14b96 | 375 | errno = 0; |
4b8a1a28 | 376 | ptrace (request, pid, (PTRACE_TYPE_ARG3)1, target_signal_to_host (signal)); |
c7c14b96 MK |
377 | if (errno != 0) |
378 | perror_with_name (("ptrace")); | |
5bf970f9 AC |
379 | } |
380 | ||
4b8a1a28 MK |
381 | /* Wait for the child specified by PTID to do something. Return the |
382 | process ID of the child, or MINUS_ONE_PTID in case of error; store | |
383 | the status in *OURSTATUS. */ | |
5bf970f9 | 384 | |
c7c14b96 MK |
385 | static ptid_t |
386 | inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
5bf970f9 | 387 | { |
4b8a1a28 MK |
388 | pid_t pid; |
389 | int status, save_errno; | |
5bf970f9 | 390 | |
c7c14b96 MK |
391 | do |
392 | { | |
4b8a1a28 | 393 | set_sigint_trap (); |
5bf970f9 | 394 | |
4b8a1a28 MK |
395 | do |
396 | { | |
397 | pid = waitpid (ptid_get_pid (ptid), &status, 0); | |
398 | save_errno = errno; | |
399 | } | |
400 | while (pid == -1 && errno == EINTR); | |
5bf970f9 | 401 | |
c7c14b96 | 402 | clear_sigint_trap (); |
5bf970f9 | 403 | |
c7c14b96 MK |
404 | if (pid == -1) |
405 | { | |
c7c14b96 | 406 | fprintf_unfiltered (gdb_stderr, |
4b8a1a28 | 407 | _("Child process unexpectedly missing: %s.\n"), |
c7c14b96 MK |
408 | safe_strerror (save_errno)); |
409 | ||
410 | /* Claim it exited with unknown signal. */ | |
411 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
412 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
fb66883a | 413 | return inferior_ptid; |
c7c14b96 MK |
414 | } |
415 | ||
4b8a1a28 MK |
416 | /* Ignore terminated detached child processes. */ |
417 | if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid)) | |
418 | pid = -1; | |
c7c14b96 | 419 | } |
4b8a1a28 | 420 | while (pid == -1); |
c7c14b96 | 421 | |
735f54b4 MK |
422 | #ifdef PT_GET_PROCESS_STATE |
423 | if (WIFSTOPPED (status)) | |
424 | { | |
425 | ptrace_state_t pe; | |
426 | pid_t fpid; | |
427 | ||
428 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
429 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
430 | perror_with_name (("ptrace")); | |
431 | ||
432 | switch (pe.pe_report_event) | |
433 | { | |
434 | case PTRACE_FORK: | |
435 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
3a3e9ee3 | 436 | ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid); |
735f54b4 MK |
437 | |
438 | /* Make sure the other end of the fork is stopped too. */ | |
439 | fpid = waitpid (pe.pe_other_pid, &status, 0); | |
440 | if (fpid == -1) | |
441 | perror_with_name (("waitpid")); | |
442 | ||
443 | if (ptrace (PT_GET_PROCESS_STATE, fpid, | |
444 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
445 | perror_with_name (("ptrace")); | |
446 | ||
447 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
448 | gdb_assert (pe.pe_other_pid == pid); | |
449 | if (fpid == ptid_get_pid (inferior_ptid)) | |
450 | { | |
3a3e9ee3 | 451 | ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid); |
735f54b4 MK |
452 | return pid_to_ptid (fpid); |
453 | } | |
454 | ||
455 | return pid_to_ptid (pid); | |
456 | } | |
457 | } | |
458 | #endif | |
459 | ||
c7c14b96 MK |
460 | store_waitstatus (ourstatus, status); |
461 | return pid_to_ptid (pid); | |
5bf970f9 AC |
462 | } |
463 | ||
4b8a1a28 MK |
464 | /* Attempt a transfer all LEN bytes starting at OFFSET between the |
465 | inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer. | |
466 | Return the number of bytes actually transferred. */ | |
5bf970f9 AC |
467 | |
468 | static LONGEST | |
469 | inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, | |
961cb7b5 MK |
470 | const char *annex, gdb_byte *readbuf, |
471 | const gdb_byte *writebuf, | |
472 | ULONGEST offset, LONGEST len) | |
5bf970f9 | 473 | { |
4b8a1a28 MK |
474 | pid_t pid = ptid_get_pid (inferior_ptid); |
475 | ||
5bf970f9 AC |
476 | switch (object) |
477 | { | |
478 | case TARGET_OBJECT_MEMORY: | |
f929a579 AC |
479 | #ifdef PT_IO |
480 | /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO | |
481 | request that promises to be much more efficient in reading | |
482 | and writing data in the traced process's address space. */ | |
483 | { | |
484 | struct ptrace_io_desc piod; | |
4b8a1a28 | 485 | |
f929a579 | 486 | /* NOTE: We assume that there are no distinct address spaces |
b457b3dd MK |
487 | for instruction and data. However, on OpenBSD 3.9 and |
488 | later, PIOD_WRITE_D doesn't allow changing memory that's | |
489 | mapped read-only. Since most code segments will be | |
490 | read-only, using PIOD_WRITE_D will prevent us from | |
491 | inserting breakpoints, so we use PIOD_WRITE_I instead. */ | |
492 | piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D; | |
f929a579 AC |
493 | piod.piod_addr = writebuf ? (void *) writebuf : readbuf; |
494 | piod.piod_offs = (void *) (long) offset; | |
495 | piod.piod_len = len; | |
496 | ||
497 | errno = 0; | |
4b8a1a28 | 498 | if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0) |
f929a579 AC |
499 | /* Return the actual number of bytes read or written. */ |
500 | return piod.piod_len; | |
501 | /* If the PT_IO request is somehow not supported, fallback on | |
502 | using PT_WRITE_D/PT_READ_D. Otherwise we will return zero | |
503 | to indicate failure. */ | |
504 | if (errno != EINVAL) | |
505 | return 0; | |
506 | } | |
507 | #endif | |
508 | { | |
509 | union | |
510 | { | |
511 | PTRACE_TYPE_RET word; | |
4b8a1a28 | 512 | gdb_byte byte[sizeof (PTRACE_TYPE_RET)]; |
f929a579 AC |
513 | } buffer; |
514 | ULONGEST rounded_offset; | |
515 | LONGEST partial_len; | |
4b8a1a28 | 516 | |
cb85a953 AC |
517 | /* Round the start offset down to the next long word |
518 | boundary. */ | |
f929a579 | 519 | rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); |
4b8a1a28 | 520 | |
cb85a953 AC |
521 | /* Since ptrace will transfer a single word starting at that |
522 | rounded_offset the partial_len needs to be adjusted down to | |
523 | that (remember this function only does a single transfer). | |
524 | Should the required length be even less, adjust it down | |
525 | again. */ | |
526 | partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset; | |
527 | if (partial_len > len) | |
f929a579 | 528 | partial_len = len; |
4b8a1a28 | 529 | |
f929a579 AC |
530 | if (writebuf) |
531 | { | |
cb85a953 AC |
532 | /* If OFFSET:PARTIAL_LEN is smaller than |
533 | ROUNDED_OFFSET:WORDSIZE then a read/modify write will | |
534 | be needed. Read in the entire word. */ | |
f929a579 | 535 | if (rounded_offset < offset |
cb85a953 AC |
536 | || (offset + partial_len |
537 | < rounded_offset + sizeof (PTRACE_TYPE_RET))) | |
f929a579 | 538 | /* Need part of initial word -- fetch it. */ |
4b8a1a28 | 539 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
540 | (PTRACE_TYPE_ARG3)(uintptr_t) |
541 | rounded_offset, 0); | |
4b8a1a28 | 542 | |
f929a579 AC |
543 | /* Copy data to be written over corresponding part of |
544 | buffer. */ | |
f6ffd89b MK |
545 | memcpy (buffer.byte + (offset - rounded_offset), |
546 | writebuf, partial_len); | |
4b8a1a28 | 547 | |
f929a579 | 548 | errno = 0; |
4b8a1a28 | 549 | ptrace (PT_WRITE_D, pid, |
f7dd0ed7 UW |
550 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
551 | buffer.word); | |
f929a579 AC |
552 | if (errno) |
553 | { | |
554 | /* Using the appropriate one (I or D) is necessary for | |
555 | Gould NP1, at least. */ | |
556 | errno = 0; | |
4b8a1a28 | 557 | ptrace (PT_WRITE_I, pid, |
f7dd0ed7 UW |
558 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
559 | buffer.word); | |
f929a579 AC |
560 | if (errno) |
561 | return 0; | |
562 | } | |
563 | } | |
4b8a1a28 | 564 | |
f929a579 AC |
565 | if (readbuf) |
566 | { | |
567 | errno = 0; | |
4b8a1a28 | 568 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
569 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
570 | 0); | |
f929a579 AC |
571 | if (errno) |
572 | return 0; | |
573 | /* Copy appropriate bytes out of the buffer. */ | |
574 | memcpy (readbuf, buffer.byte + (offset - rounded_offset), | |
575 | partial_len); | |
576 | } | |
4b8a1a28 | 577 | |
f929a579 AC |
578 | return partial_len; |
579 | } | |
5bf970f9 AC |
580 | |
581 | case TARGET_OBJECT_UNWIND_TABLE: | |
582 | return -1; | |
583 | ||
584 | case TARGET_OBJECT_AUXV: | |
585 | return -1; | |
586 | ||
587 | case TARGET_OBJECT_WCOOKIE: | |
588 | return -1; | |
589 | ||
590 | default: | |
591 | return -1; | |
592 | } | |
593 | } | |
594 | ||
4b8a1a28 | 595 | /* Return non-zero if the thread specified by PTID is alive. */ |
c7c14b96 MK |
596 | |
597 | static int | |
598 | inf_ptrace_thread_alive (ptid_t ptid) | |
599 | { | |
4b8a1a28 MK |
600 | /* ??? Is kill the right way to do this? */ |
601 | return (kill (ptid_get_pid (ptid), 0) != -1); | |
c7c14b96 MK |
602 | } |
603 | ||
604 | /* Print status information about what we're accessing. */ | |
605 | ||
606 | static void | |
607 | inf_ptrace_files_info (struct target_ops *ignore) | |
608 | { | |
181e7f93 PA |
609 | struct inferior *inf = current_inferior (); |
610 | ||
4b8a1a28 | 611 | printf_filtered (_("\tUsing the running image of %s %s.\n"), |
181e7f93 | 612 | inf->attach_flag ? "attached" : "child", |
4b8a1a28 | 613 | target_pid_to_str (inferior_ptid)); |
5bf970f9 AC |
614 | } |
615 | ||
8785ced0 MK |
616 | /* Create a prototype ptrace target. The client can override it with |
617 | local methods. */ | |
618 | ||
5bf970f9 AC |
619 | struct target_ops * |
620 | inf_ptrace_target (void) | |
621 | { | |
622 | struct target_ops *t = inf_child_target (); | |
8785ced0 | 623 | |
5bf970f9 | 624 | t->to_attach = inf_ptrace_attach; |
5bf970f9 AC |
625 | t->to_detach = inf_ptrace_detach; |
626 | t->to_resume = inf_ptrace_resume; | |
627 | t->to_wait = inf_ptrace_wait; | |
5bf970f9 | 628 | t->to_files_info = inf_ptrace_files_info; |
4b8a1a28 | 629 | t->to_kill = inf_ptrace_kill; |
5bf970f9 | 630 | t->to_create_inferior = inf_ptrace_create_inferior; |
735f54b4 MK |
631 | #ifdef PT_GET_PROCESS_STATE |
632 | t->to_follow_fork = inf_ptrace_follow_fork; | |
e4ef629d MK |
633 | t->to_post_startup_inferior = inf_ptrace_post_startup_inferior; |
634 | t->to_post_attach = inf_ptrace_post_attach; | |
735f54b4 | 635 | #endif |
5bf970f9 | 636 | t->to_mourn_inferior = inf_ptrace_mourn_inferior; |
5bf970f9 | 637 | t->to_thread_alive = inf_ptrace_thread_alive; |
4b8a1a28 | 638 | t->to_pid_to_str = normal_pid_to_str; |
5bf970f9 | 639 | t->to_stop = inf_ptrace_stop; |
c7c14b96 | 640 | t->to_xfer_partial = inf_ptrace_xfer_partial; |
8785ced0 MK |
641 | |
642 | return t; | |
643 | } | |
644 | \f | |
645 | ||
4b8a1a28 | 646 | /* Pointer to a function that returns the offset within the user area |
8785ced0 | 647 | where a particular register is stored. */ |
7714d83a | 648 | static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int); |
8785ced0 MK |
649 | |
650 | /* Fetch register REGNUM from the inferior. */ | |
651 | ||
652 | static void | |
56be3814 | 653 | inf_ptrace_fetch_register (struct regcache *regcache, int regnum) |
8785ced0 | 654 | { |
3b3b1423 | 655 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
8785ced0 MK |
656 | CORE_ADDR addr; |
657 | size_t size; | |
658 | PTRACE_TYPE_RET *buf; | |
659 | int pid, i; | |
660 | ||
7714d83a | 661 | /* This isn't really an address, but ptrace thinks of it as one. */ |
3b3b1423 | 662 | addr = inf_ptrace_register_u_offset (gdbarch, regnum, 0); |
8d4c1ba3 | 663 | if (addr == (CORE_ADDR)-1 |
3b3b1423 | 664 | || gdbarch_cannot_fetch_register (gdbarch, regnum)) |
10d6c8cd | 665 | { |
56be3814 | 666 | regcache_raw_supply (regcache, regnum, NULL); |
10d6c8cd DJ |
667 | return; |
668 | } | |
669 | ||
8785ced0 | 670 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 671 | separate processes. */ |
8785ced0 MK |
672 | pid = ptid_get_lwp (inferior_ptid); |
673 | if (pid == 0) | |
674 | pid = ptid_get_pid (inferior_ptid); | |
675 | ||
3b3b1423 | 676 | size = register_size (gdbarch, regnum); |
8785ced0 MK |
677 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
678 | buf = alloca (size); | |
679 | ||
10d6c8cd | 680 | /* Read the register contents from the inferior a chunk at a time. */ |
8785ced0 MK |
681 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
682 | { | |
683 | errno = 0; | |
f7dd0ed7 | 684 | buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, 0); |
8785ced0 | 685 | if (errno != 0) |
4b8a1a28 | 686 | error (_("Couldn't read register %s (#%d): %s."), |
3b3b1423 | 687 | gdbarch_register_name (gdbarch, regnum), |
c9f4d572 | 688 | regnum, safe_strerror (errno)); |
8785ced0 MK |
689 | |
690 | addr += sizeof (PTRACE_TYPE_RET); | |
691 | } | |
56be3814 | 692 | regcache_raw_supply (regcache, regnum, buf); |
8785ced0 MK |
693 | } |
694 | ||
695 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this | |
696 | for all registers. */ | |
697 | ||
698 | static void | |
56be3814 | 699 | inf_ptrace_fetch_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
700 | { |
701 | if (regnum == -1) | |
3b3b1423 UW |
702 | for (regnum = 0; |
703 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); | |
704 | regnum++) | |
56be3814 | 705 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 | 706 | else |
56be3814 | 707 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 MK |
708 | } |
709 | ||
710 | /* Store register REGNUM into the inferior. */ | |
711 | ||
712 | static void | |
56be3814 | 713 | inf_ptrace_store_register (const struct regcache *regcache, int regnum) |
8785ced0 | 714 | { |
3b3b1423 | 715 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
8785ced0 MK |
716 | CORE_ADDR addr; |
717 | size_t size; | |
718 | PTRACE_TYPE_RET *buf; | |
719 | int pid, i; | |
720 | ||
7714d83a | 721 | /* This isn't really an address, but ptrace thinks of it as one. */ |
3b3b1423 | 722 | addr = inf_ptrace_register_u_offset (gdbarch, regnum, 1); |
8d4c1ba3 | 723 | if (addr == (CORE_ADDR)-1 |
3b3b1423 | 724 | || gdbarch_cannot_store_register (gdbarch, regnum)) |
10d6c8cd DJ |
725 | return; |
726 | ||
8785ced0 | 727 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 728 | separate processes. */ |
8785ced0 MK |
729 | pid = ptid_get_lwp (inferior_ptid); |
730 | if (pid == 0) | |
731 | pid = ptid_get_pid (inferior_ptid); | |
732 | ||
3b3b1423 | 733 | size = register_size (gdbarch, regnum); |
8785ced0 MK |
734 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
735 | buf = alloca (size); | |
736 | ||
10d6c8cd | 737 | /* Write the register contents into the inferior a chunk at a time. */ |
56be3814 | 738 | regcache_raw_collect (regcache, regnum, buf); |
8785ced0 MK |
739 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
740 | { | |
741 | errno = 0; | |
f7dd0ed7 | 742 | ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]); |
8785ced0 | 743 | if (errno != 0) |
4b8a1a28 | 744 | error (_("Couldn't write register %s (#%d): %s."), |
3b3b1423 | 745 | gdbarch_register_name (gdbarch, regnum), |
c9f4d572 | 746 | regnum, safe_strerror (errno)); |
8785ced0 MK |
747 | |
748 | addr += sizeof (PTRACE_TYPE_RET); | |
749 | } | |
750 | } | |
751 | ||
752 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do | |
753 | this for all registers. */ | |
754 | ||
755 | void | |
56be3814 | 756 | inf_ptrace_store_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
757 | { |
758 | if (regnum == -1) | |
3b3b1423 UW |
759 | for (regnum = 0; |
760 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); | |
761 | regnum++) | |
56be3814 | 762 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 | 763 | else |
56be3814 | 764 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 MK |
765 | } |
766 | ||
767 | /* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be | |
768 | a function returning the offset within the user area where a | |
769 | particular register is stored. */ | |
770 | ||
771 | struct target_ops * | |
7714d83a UW |
772 | inf_ptrace_trad_target (CORE_ADDR (*register_u_offset) |
773 | (struct gdbarch *, int, int)) | |
8785ced0 MK |
774 | { |
775 | struct target_ops *t = inf_ptrace_target(); | |
776 | ||
777 | gdb_assert (register_u_offset); | |
778 | inf_ptrace_register_u_offset = register_u_offset; | |
779 | t->to_fetch_registers = inf_ptrace_fetch_registers; | |
780 | t->to_store_registers = inf_ptrace_store_registers; | |
781 | ||
5bf970f9 AC |
782 | return t; |
783 | } |