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, |
9b254dd1 | 4 | 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007, 2008 |
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 MK |
37 | |
38 | /* HACK: Save the ptrace ops returned by inf_ptrace_target. */ | |
5bf970f9 | 39 | static struct target_ops *ptrace_ops_hack; |
c7c14b96 MK |
40 | \f |
41 | ||
735f54b4 MK |
42 | #ifdef PT_GET_PROCESS_STATE |
43 | ||
44 | static int | |
ee057212 | 45 | inf_ptrace_follow_fork (struct target_ops *ops, int follow_child) |
735f54b4 MK |
46 | { |
47 | pid_t pid, fpid; | |
48 | ptrace_state_t pe; | |
4e1c45ea | 49 | struct thread_info *last_tp = NULL; |
735f54b4 MK |
50 | |
51 | /* FIXME: kettenis/20050720: This stuff should really be passed as | |
52 | an argument by our caller. */ | |
53 | { | |
54 | ptid_t ptid; | |
55 | struct target_waitstatus status; | |
56 | ||
57 | get_last_target_status (&ptid, &status); | |
58 | gdb_assert (status.kind == TARGET_WAITKIND_FORKED); | |
59 | ||
60 | pid = ptid_get_pid (ptid); | |
4e1c45ea | 61 | last_tp = find_thread_pid (ptid); |
735f54b4 MK |
62 | } |
63 | ||
64 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
65 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
66 | perror_with_name (("ptrace")); | |
67 | ||
68 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
69 | fpid = pe.pe_other_pid; | |
70 | ||
71 | if (follow_child) | |
72 | { | |
4e1c45ea PA |
73 | /* Copy user stepping state to the new inferior thread. */ |
74 | struct breakpoint *step_resume_breakpoint = last_tp->step_resume_breakpoint; | |
75 | CORE_ADDR step_range_start = last_tp->step_range_start; | |
76 | CORE_ADDR step_range_end = last_tp->step_range_end; | |
77 | struct frame_id step_frame_id = last_tp->step_frame_id; | |
735f54b4 | 78 | |
4e1c45ea PA |
79 | struct thread_info *tp; |
80 | ||
81 | /* Otherwise, deleting the parent would get rid of this | |
82 | breakpoint. */ | |
83 | last_tp->step_resume_breakpoint = NULL; | |
84 | ||
85 | /* Before detaching from the parent, remove all breakpoints from | |
86 | it. */ | |
87 | detach_breakpoints (pid); | |
735f54b4 MK |
88 | |
89 | if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
90 | perror_with_name (("ptrace")); | |
4e1c45ea | 91 | |
7f9f62ba PA |
92 | /* Switch inferior_ptid out of the parent's way. */ |
93 | inferior_ptid = pid_to_ptid (fpid); | |
94 | ||
4e1c45ea | 95 | /* Delete the parent. */ |
7f9f62ba | 96 | detach_inferior (pid); |
4e1c45ea PA |
97 | |
98 | /* Add the child. */ | |
7f9f62ba | 99 | add_inferior (fpid); |
4e1c45ea PA |
100 | tp = add_thread_silent (inferior_ptid); |
101 | ||
102 | tp->step_resume_breakpoint = step_resume_breakpoint; | |
103 | tp->step_range_start = step_range_start; | |
104 | tp->step_range_end = step_range_end; | |
105 | tp->step_frame_id = step_frame_id; | |
106 | ||
107 | /* Reset breakpoints in the child as appropriate. */ | |
108 | follow_inferior_reset_breakpoints (); | |
735f54b4 MK |
109 | } |
110 | else | |
111 | { | |
112 | inferior_ptid = pid_to_ptid (pid); | |
113 | detach_breakpoints (fpid); | |
114 | ||
115 | if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
116 | perror_with_name (("ptrace")); | |
7f9f62ba | 117 | detach_inferior (pid); |
735f54b4 MK |
118 | } |
119 | ||
120 | return 0; | |
121 | } | |
122 | ||
123 | #endif /* PT_GET_PROCESS_STATE */ | |
124 | \f | |
125 | ||
4b8a1a28 | 126 | /* Prepare to be traced. */ |
5bf970f9 AC |
127 | |
128 | static void | |
c7c14b96 | 129 | inf_ptrace_me (void) |
5bf970f9 | 130 | { |
c7c14b96 | 131 | /* "Trace me, Dr. Memory!" */ |
4b8a1a28 | 132 | ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0); |
5bf970f9 AC |
133 | } |
134 | ||
4b8a1a28 | 135 | /* Start tracing PID. */ |
5bf970f9 AC |
136 | |
137 | static void | |
c7c14b96 | 138 | inf_ptrace_him (int pid) |
5bf970f9 | 139 | { |
c7c14b96 | 140 | push_target (ptrace_ops_hack); |
5bf970f9 | 141 | |
c7c14b96 MK |
142 | /* On some targets, there must be some explicit synchronization |
143 | between the parent and child processes after the debugger | |
144 | forks, and before the child execs the debuggee program. This | |
145 | call basically gives permission for the child to exec. */ | |
5bf970f9 | 146 | |
c7c14b96 | 147 | target_acknowledge_created_inferior (pid); |
5bf970f9 | 148 | |
c7c14b96 MK |
149 | /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will |
150 | be 1 or 2 depending on whether we're starting without or with a | |
151 | shell. */ | |
152 | startup_inferior (START_INFERIOR_TRAPS_EXPECTED); | |
153 | ||
154 | /* On some targets, there must be some explicit actions taken after | |
155 | the inferior has been started up. */ | |
156 | target_post_startup_inferior (pid_to_ptid (pid)); | |
5bf970f9 AC |
157 | } |
158 | ||
4b8a1a28 MK |
159 | /* Start a new inferior Unix child process. EXEC_FILE is the file to |
160 | run, ALLARGS is a string containing the arguments to the program. | |
161 | ENV is the environment vector to pass. If FROM_TTY is non-zero, be | |
162 | chatty about it. */ | |
5bf970f9 | 163 | |
c7c14b96 MK |
164 | static void |
165 | inf_ptrace_create_inferior (char *exec_file, char *allargs, char **env, | |
166 | int from_tty) | |
5bf970f9 | 167 | { |
c7c14b96 MK |
168 | fork_inferior (exec_file, allargs, env, inf_ptrace_me, inf_ptrace_him, |
169 | NULL, NULL); | |
5bf970f9 AC |
170 | } |
171 | ||
e4ef629d MK |
172 | #ifdef PT_GET_PROCESS_STATE |
173 | ||
174 | static void | |
175 | inf_ptrace_post_startup_inferior (ptid_t pid) | |
176 | { | |
177 | ptrace_event_t pe; | |
178 | ||
179 | /* Set the initial event mask. */ | |
180 | memset (&pe, 0, sizeof pe); | |
181 | pe.pe_set_event |= PTRACE_FORK; | |
182 | if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid), | |
183 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
184 | perror_with_name (("ptrace")); | |
185 | } | |
186 | ||
187 | #endif | |
188 | ||
4b8a1a28 MK |
189 | /* Clean up a rotting corpse of an inferior after it died. */ |
190 | ||
c7c14b96 MK |
191 | static void |
192 | inf_ptrace_mourn_inferior (void) | |
5bf970f9 | 193 | { |
4b8a1a28 MK |
194 | int status; |
195 | ||
196 | /* Wait just one more time to collect the inferior's exit status. | |
f010475d | 197 | Do not check whether this succeeds though, since we may be |
4b8a1a28 | 198 | dealing with a process that we attached to. Such a process will |
3d450bdd | 199 | only report its exit status to its original parent. */ |
4b8a1a28 MK |
200 | waitpid (ptid_get_pid (inferior_ptid), &status, 0); |
201 | ||
c7c14b96 MK |
202 | unpush_target (ptrace_ops_hack); |
203 | generic_mourn_inferior (); | |
5bf970f9 AC |
204 | } |
205 | ||
4b8a1a28 MK |
206 | /* Attach to the process specified by ARGS. If FROM_TTY is non-zero, |
207 | be chatty about it. */ | |
5bf970f9 AC |
208 | |
209 | static void | |
210 | inf_ptrace_attach (char *args, int from_tty) | |
211 | { | |
212 | char *exec_file; | |
4b8a1a28 | 213 | pid_t pid; |
5bf970f9 | 214 | char *dummy; |
181e7f93 | 215 | struct inferior *inf; |
5bf970f9 AC |
216 | |
217 | if (!args) | |
e2e0b3e5 | 218 | error_no_arg (_("process-id to attach")); |
5bf970f9 AC |
219 | |
220 | dummy = args; | |
221 | pid = strtol (args, &dummy, 0); | |
f6ffd89b | 222 | /* Some targets don't set errno on errors, grrr! */ |
6e1e94ea | 223 | if (pid == 0 && args == dummy) |
8a3fe4f8 | 224 | error (_("Illegal process-id: %s."), args); |
5bf970f9 | 225 | |
f6ffd89b | 226 | if (pid == getpid ()) /* Trying to masturbate? */ |
8a3fe4f8 | 227 | error (_("I refuse to debug myself!")); |
5bf970f9 AC |
228 | |
229 | if (from_tty) | |
230 | { | |
4b8a1a28 | 231 | exec_file = get_exec_file (0); |
5bf970f9 AC |
232 | |
233 | if (exec_file) | |
a3f17187 | 234 | printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, |
5bf970f9 AC |
235 | target_pid_to_str (pid_to_ptid (pid))); |
236 | else | |
a3f17187 | 237 | printf_unfiltered (_("Attaching to %s\n"), |
5bf970f9 AC |
238 | target_pid_to_str (pid_to_ptid (pid))); |
239 | ||
240 | gdb_flush (gdb_stdout); | |
241 | } | |
242 | ||
6e1e94ea MK |
243 | #ifdef PT_ATTACH |
244 | errno = 0; | |
4b8a1a28 | 245 | ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0); |
6e1e94ea | 246 | if (errno != 0) |
e2e0b3e5 | 247 | perror_with_name (("ptrace")); |
6e1e94ea | 248 | #else |
8a3fe4f8 | 249 | error (_("This system does not support attaching to a process")); |
6e1e94ea | 250 | #endif |
5bf970f9 AC |
251 | |
252 | inferior_ptid = pid_to_ptid (pid); | |
af990527 | 253 | |
181e7f93 PA |
254 | inf = add_inferior (pid); |
255 | inf->attach_flag = 1; | |
7f9f62ba | 256 | |
af990527 PA |
257 | /* Always add a main thread. If some target extends the ptrace |
258 | target, it should decorate the ptid later with more info. */ | |
259 | add_thread_silent (inferior_ptid); | |
260 | ||
5bf970f9 AC |
261 | push_target (ptrace_ops_hack); |
262 | } | |
263 | ||
e4ef629d MK |
264 | #ifdef PT_GET_PROCESS_STATE |
265 | ||
266 | void | |
267 | inf_ptrace_post_attach (int pid) | |
268 | { | |
269 | ptrace_event_t pe; | |
270 | ||
271 | /* Set the initial event mask. */ | |
272 | memset (&pe, 0, sizeof pe); | |
273 | pe.pe_set_event |= PTRACE_FORK; | |
274 | if (ptrace (PT_SET_EVENT_MASK, pid, | |
275 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
276 | perror_with_name (("ptrace")); | |
277 | } | |
278 | ||
279 | #endif | |
280 | ||
4b8a1a28 | 281 | /* Detach from the inferior, optionally passing it the signal |
f010475d | 282 | specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ |
5bf970f9 AC |
283 | |
284 | static void | |
285 | inf_ptrace_detach (char *args, int from_tty) | |
286 | { | |
4b8a1a28 | 287 | pid_t pid = ptid_get_pid (inferior_ptid); |
6e1e94ea | 288 | int sig = 0; |
5bf970f9 AC |
289 | |
290 | if (from_tty) | |
291 | { | |
292 | char *exec_file = get_exec_file (0); | |
293 | if (exec_file == 0) | |
294 | exec_file = ""; | |
a3f17187 | 295 | printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, |
5bf970f9 AC |
296 | target_pid_to_str (pid_to_ptid (pid))); |
297 | gdb_flush (gdb_stdout); | |
298 | } | |
299 | if (args) | |
6e1e94ea | 300 | sig = atoi (args); |
5bf970f9 | 301 | |
6e1e94ea | 302 | #ifdef PT_DETACH |
4b8a1a28 | 303 | /* We'd better not have left any breakpoints in the program or it'll |
f010475d | 304 | die when it hits one. Also note that this may only work if we |
4b8a1a28 MK |
305 | previously attached to the inferior. It *might* work if we |
306 | started the process ourselves. */ | |
6e1e94ea | 307 | errno = 0; |
4b8a1a28 | 308 | ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig); |
6e1e94ea | 309 | if (errno != 0) |
e2e0b3e5 | 310 | perror_with_name (("ptrace")); |
6e1e94ea | 311 | #else |
8a3fe4f8 | 312 | error (_("This system does not support detaching from a process")); |
6e1e94ea | 313 | #endif |
5bf970f9 AC |
314 | |
315 | inferior_ptid = null_ptid; | |
7f9f62ba | 316 | detach_inferior (pid); |
5bf970f9 AC |
317 | unpush_target (ptrace_ops_hack); |
318 | } | |
319 | ||
4b8a1a28 MK |
320 | /* Kill the inferior. */ |
321 | ||
5bf970f9 | 322 | static void |
4b8a1a28 | 323 | inf_ptrace_kill (void) |
5bf970f9 | 324 | { |
4b8a1a28 | 325 | pid_t pid = ptid_get_pid (inferior_ptid); |
c7c14b96 | 326 | int status; |
c7c14b96 MK |
327 | |
328 | if (pid == 0) | |
329 | return; | |
330 | ||
4b8a1a28 MK |
331 | ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0); |
332 | waitpid (pid, &status, 0); | |
333 | ||
c7c14b96 | 334 | target_mourn_inferior (); |
5bf970f9 AC |
335 | } |
336 | ||
4b8a1a28 | 337 | /* Stop the inferior. */ |
c7c14b96 | 338 | |
5bf970f9 | 339 | static void |
94cc34af | 340 | inf_ptrace_stop (ptid_t ptid) |
5bf970f9 | 341 | { |
4b8a1a28 MK |
342 | /* Send a SIGINT to the process group. This acts just like the user |
343 | typed a ^C on the controlling terminal. Note that using a | |
344 | negative process number in kill() is a System V-ism. The proper | |
345 | BSD interface is killpg(). However, all modern BSDs support the | |
346 | System V interface too. */ | |
c7c14b96 | 347 | kill (-inferior_process_group, SIGINT); |
5bf970f9 AC |
348 | } |
349 | ||
4b8a1a28 MK |
350 | /* Resume execution of thread PTID, or all threads if PTID is -1. If |
351 | STEP is nonzero, single-step it. If SIGNAL is nonzero, give it | |
352 | that signal. */ | |
5bf970f9 AC |
353 | |
354 | static void | |
c7c14b96 | 355 | inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal) |
5bf970f9 | 356 | { |
4b8a1a28 | 357 | pid_t pid = ptid_get_pid (ptid); |
c7c14b96 | 358 | int request = PT_CONTINUE; |
c7c14b96 MK |
359 | |
360 | if (pid == -1) | |
4b8a1a28 MK |
361 | /* Resume all threads. Traditionally ptrace() only supports |
362 | single-threaded processes, so simply resume the inferior. */ | |
363 | pid = ptid_get_pid (inferior_ptid); | |
c7c14b96 MK |
364 | |
365 | if (step) | |
366 | { | |
367 | /* If this system does not support PT_STEP, a higher level | |
368 | function will have called single_step() to transmute the step | |
369 | request into a continue request (by setting breakpoints on | |
370 | all possible successor instructions), so we don't have to | |
371 | worry about that here. */ | |
372 | request = PT_STEP; | |
373 | } | |
374 | ||
375 | /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from | |
376 | where it was. If GDB wanted it to start some other way, we have | |
4b8a1a28 | 377 | already written a new program counter value to the child. */ |
c7c14b96 | 378 | errno = 0; |
4b8a1a28 | 379 | ptrace (request, pid, (PTRACE_TYPE_ARG3)1, target_signal_to_host (signal)); |
c7c14b96 MK |
380 | if (errno != 0) |
381 | perror_with_name (("ptrace")); | |
5bf970f9 AC |
382 | } |
383 | ||
4b8a1a28 MK |
384 | /* Wait for the child specified by PTID to do something. Return the |
385 | process ID of the child, or MINUS_ONE_PTID in case of error; store | |
386 | the status in *OURSTATUS. */ | |
5bf970f9 | 387 | |
c7c14b96 MK |
388 | static ptid_t |
389 | inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
5bf970f9 | 390 | { |
4b8a1a28 MK |
391 | pid_t pid; |
392 | int status, save_errno; | |
5bf970f9 | 393 | |
c7c14b96 MK |
394 | do |
395 | { | |
4b8a1a28 | 396 | set_sigint_trap (); |
c7c14b96 | 397 | set_sigio_trap (); |
5bf970f9 | 398 | |
4b8a1a28 MK |
399 | do |
400 | { | |
401 | pid = waitpid (ptid_get_pid (ptid), &status, 0); | |
402 | save_errno = errno; | |
403 | } | |
404 | while (pid == -1 && errno == EINTR); | |
5bf970f9 | 405 | |
c7c14b96 | 406 | clear_sigio_trap (); |
c7c14b96 | 407 | clear_sigint_trap (); |
5bf970f9 | 408 | |
c7c14b96 MK |
409 | if (pid == -1) |
410 | { | |
c7c14b96 | 411 | fprintf_unfiltered (gdb_stderr, |
4b8a1a28 | 412 | _("Child process unexpectedly missing: %s.\n"), |
c7c14b96 MK |
413 | safe_strerror (save_errno)); |
414 | ||
415 | /* Claim it exited with unknown signal. */ | |
416 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
417 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
4b8a1a28 | 418 | return minus_one_ptid; |
c7c14b96 MK |
419 | } |
420 | ||
4b8a1a28 MK |
421 | /* Ignore terminated detached child processes. */ |
422 | if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid)) | |
423 | pid = -1; | |
c7c14b96 | 424 | } |
4b8a1a28 | 425 | while (pid == -1); |
c7c14b96 | 426 | |
735f54b4 MK |
427 | #ifdef PT_GET_PROCESS_STATE |
428 | if (WIFSTOPPED (status)) | |
429 | { | |
430 | ptrace_state_t pe; | |
431 | pid_t fpid; | |
432 | ||
433 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
434 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
435 | perror_with_name (("ptrace")); | |
436 | ||
437 | switch (pe.pe_report_event) | |
438 | { | |
439 | case PTRACE_FORK: | |
440 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
3a3e9ee3 | 441 | ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid); |
735f54b4 MK |
442 | |
443 | /* Make sure the other end of the fork is stopped too. */ | |
444 | fpid = waitpid (pe.pe_other_pid, &status, 0); | |
445 | if (fpid == -1) | |
446 | perror_with_name (("waitpid")); | |
447 | ||
448 | if (ptrace (PT_GET_PROCESS_STATE, fpid, | |
449 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
450 | perror_with_name (("ptrace")); | |
451 | ||
452 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
453 | gdb_assert (pe.pe_other_pid == pid); | |
454 | if (fpid == ptid_get_pid (inferior_ptid)) | |
455 | { | |
3a3e9ee3 | 456 | ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid); |
735f54b4 MK |
457 | return pid_to_ptid (fpid); |
458 | } | |
459 | ||
460 | return pid_to_ptid (pid); | |
461 | } | |
462 | } | |
463 | #endif | |
464 | ||
c7c14b96 MK |
465 | store_waitstatus (ourstatus, status); |
466 | return pid_to_ptid (pid); | |
5bf970f9 AC |
467 | } |
468 | ||
4b8a1a28 MK |
469 | /* Attempt a transfer all LEN bytes starting at OFFSET between the |
470 | inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer. | |
471 | Return the number of bytes actually transferred. */ | |
5bf970f9 AC |
472 | |
473 | static LONGEST | |
474 | inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, | |
961cb7b5 MK |
475 | const char *annex, gdb_byte *readbuf, |
476 | const gdb_byte *writebuf, | |
477 | ULONGEST offset, LONGEST len) | |
5bf970f9 | 478 | { |
4b8a1a28 MK |
479 | pid_t pid = ptid_get_pid (inferior_ptid); |
480 | ||
5bf970f9 AC |
481 | switch (object) |
482 | { | |
483 | case TARGET_OBJECT_MEMORY: | |
f929a579 AC |
484 | #ifdef PT_IO |
485 | /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO | |
486 | request that promises to be much more efficient in reading | |
487 | and writing data in the traced process's address space. */ | |
488 | { | |
489 | struct ptrace_io_desc piod; | |
4b8a1a28 | 490 | |
f929a579 | 491 | /* NOTE: We assume that there are no distinct address spaces |
b457b3dd MK |
492 | for instruction and data. However, on OpenBSD 3.9 and |
493 | later, PIOD_WRITE_D doesn't allow changing memory that's | |
494 | mapped read-only. Since most code segments will be | |
495 | read-only, using PIOD_WRITE_D will prevent us from | |
496 | inserting breakpoints, so we use PIOD_WRITE_I instead. */ | |
497 | piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D; | |
f929a579 AC |
498 | piod.piod_addr = writebuf ? (void *) writebuf : readbuf; |
499 | piod.piod_offs = (void *) (long) offset; | |
500 | piod.piod_len = len; | |
501 | ||
502 | errno = 0; | |
4b8a1a28 | 503 | if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0) |
f929a579 AC |
504 | /* Return the actual number of bytes read or written. */ |
505 | return piod.piod_len; | |
506 | /* If the PT_IO request is somehow not supported, fallback on | |
507 | using PT_WRITE_D/PT_READ_D. Otherwise we will return zero | |
508 | to indicate failure. */ | |
509 | if (errno != EINVAL) | |
510 | return 0; | |
511 | } | |
512 | #endif | |
513 | { | |
514 | union | |
515 | { | |
516 | PTRACE_TYPE_RET word; | |
4b8a1a28 | 517 | gdb_byte byte[sizeof (PTRACE_TYPE_RET)]; |
f929a579 AC |
518 | } buffer; |
519 | ULONGEST rounded_offset; | |
520 | LONGEST partial_len; | |
4b8a1a28 | 521 | |
cb85a953 AC |
522 | /* Round the start offset down to the next long word |
523 | boundary. */ | |
f929a579 | 524 | rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); |
4b8a1a28 | 525 | |
cb85a953 AC |
526 | /* Since ptrace will transfer a single word starting at that |
527 | rounded_offset the partial_len needs to be adjusted down to | |
528 | that (remember this function only does a single transfer). | |
529 | Should the required length be even less, adjust it down | |
530 | again. */ | |
531 | partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset; | |
532 | if (partial_len > len) | |
f929a579 | 533 | partial_len = len; |
4b8a1a28 | 534 | |
f929a579 AC |
535 | if (writebuf) |
536 | { | |
cb85a953 AC |
537 | /* If OFFSET:PARTIAL_LEN is smaller than |
538 | ROUNDED_OFFSET:WORDSIZE then a read/modify write will | |
539 | be needed. Read in the entire word. */ | |
f929a579 | 540 | if (rounded_offset < offset |
cb85a953 AC |
541 | || (offset + partial_len |
542 | < rounded_offset + sizeof (PTRACE_TYPE_RET))) | |
f929a579 | 543 | /* Need part of initial word -- fetch it. */ |
4b8a1a28 | 544 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
545 | (PTRACE_TYPE_ARG3)(uintptr_t) |
546 | rounded_offset, 0); | |
4b8a1a28 | 547 | |
f929a579 AC |
548 | /* Copy data to be written over corresponding part of |
549 | buffer. */ | |
f6ffd89b MK |
550 | memcpy (buffer.byte + (offset - rounded_offset), |
551 | writebuf, partial_len); | |
4b8a1a28 | 552 | |
f929a579 | 553 | errno = 0; |
4b8a1a28 | 554 | ptrace (PT_WRITE_D, pid, |
f7dd0ed7 UW |
555 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
556 | buffer.word); | |
f929a579 AC |
557 | if (errno) |
558 | { | |
559 | /* Using the appropriate one (I or D) is necessary for | |
560 | Gould NP1, at least. */ | |
561 | errno = 0; | |
4b8a1a28 | 562 | ptrace (PT_WRITE_I, pid, |
f7dd0ed7 UW |
563 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
564 | buffer.word); | |
f929a579 AC |
565 | if (errno) |
566 | return 0; | |
567 | } | |
568 | } | |
4b8a1a28 | 569 | |
f929a579 AC |
570 | if (readbuf) |
571 | { | |
572 | errno = 0; | |
4b8a1a28 | 573 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
574 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
575 | 0); | |
f929a579 AC |
576 | if (errno) |
577 | return 0; | |
578 | /* Copy appropriate bytes out of the buffer. */ | |
579 | memcpy (readbuf, buffer.byte + (offset - rounded_offset), | |
580 | partial_len); | |
581 | } | |
4b8a1a28 | 582 | |
f929a579 AC |
583 | return partial_len; |
584 | } | |
5bf970f9 AC |
585 | |
586 | case TARGET_OBJECT_UNWIND_TABLE: | |
587 | return -1; | |
588 | ||
589 | case TARGET_OBJECT_AUXV: | |
590 | return -1; | |
591 | ||
592 | case TARGET_OBJECT_WCOOKIE: | |
593 | return -1; | |
594 | ||
595 | default: | |
596 | return -1; | |
597 | } | |
598 | } | |
599 | ||
4b8a1a28 | 600 | /* Return non-zero if the thread specified by PTID is alive. */ |
c7c14b96 MK |
601 | |
602 | static int | |
603 | inf_ptrace_thread_alive (ptid_t ptid) | |
604 | { | |
4b8a1a28 MK |
605 | /* ??? Is kill the right way to do this? */ |
606 | return (kill (ptid_get_pid (ptid), 0) != -1); | |
c7c14b96 MK |
607 | } |
608 | ||
609 | /* Print status information about what we're accessing. */ | |
610 | ||
611 | static void | |
612 | inf_ptrace_files_info (struct target_ops *ignore) | |
613 | { | |
181e7f93 PA |
614 | struct inferior *inf = current_inferior (); |
615 | ||
4b8a1a28 | 616 | printf_filtered (_("\tUsing the running image of %s %s.\n"), |
181e7f93 | 617 | inf->attach_flag ? "attached" : "child", |
4b8a1a28 | 618 | target_pid_to_str (inferior_ptid)); |
5bf970f9 AC |
619 | } |
620 | ||
8785ced0 MK |
621 | /* Create a prototype ptrace target. The client can override it with |
622 | local methods. */ | |
623 | ||
5bf970f9 AC |
624 | struct target_ops * |
625 | inf_ptrace_target (void) | |
626 | { | |
627 | struct target_ops *t = inf_child_target (); | |
8785ced0 | 628 | |
5bf970f9 | 629 | t->to_attach = inf_ptrace_attach; |
5bf970f9 AC |
630 | t->to_detach = inf_ptrace_detach; |
631 | t->to_resume = inf_ptrace_resume; | |
632 | t->to_wait = inf_ptrace_wait; | |
5bf970f9 | 633 | t->to_files_info = inf_ptrace_files_info; |
4b8a1a28 | 634 | t->to_kill = inf_ptrace_kill; |
5bf970f9 | 635 | t->to_create_inferior = inf_ptrace_create_inferior; |
735f54b4 MK |
636 | #ifdef PT_GET_PROCESS_STATE |
637 | t->to_follow_fork = inf_ptrace_follow_fork; | |
e4ef629d MK |
638 | t->to_post_startup_inferior = inf_ptrace_post_startup_inferior; |
639 | t->to_post_attach = inf_ptrace_post_attach; | |
735f54b4 | 640 | #endif |
5bf970f9 | 641 | t->to_mourn_inferior = inf_ptrace_mourn_inferior; |
5bf970f9 | 642 | t->to_thread_alive = inf_ptrace_thread_alive; |
4b8a1a28 | 643 | t->to_pid_to_str = normal_pid_to_str; |
5bf970f9 | 644 | t->to_stop = inf_ptrace_stop; |
c7c14b96 | 645 | t->to_xfer_partial = inf_ptrace_xfer_partial; |
8785ced0 | 646 | |
c7c14b96 | 647 | ptrace_ops_hack = t; |
8785ced0 MK |
648 | return t; |
649 | } | |
650 | \f | |
651 | ||
4b8a1a28 | 652 | /* Pointer to a function that returns the offset within the user area |
8785ced0 | 653 | where a particular register is stored. */ |
7714d83a | 654 | static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int); |
8785ced0 MK |
655 | |
656 | /* Fetch register REGNUM from the inferior. */ | |
657 | ||
658 | static void | |
56be3814 | 659 | inf_ptrace_fetch_register (struct regcache *regcache, int regnum) |
8785ced0 | 660 | { |
3b3b1423 | 661 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
8785ced0 MK |
662 | CORE_ADDR addr; |
663 | size_t size; | |
664 | PTRACE_TYPE_RET *buf; | |
665 | int pid, i; | |
666 | ||
7714d83a | 667 | /* This isn't really an address, but ptrace thinks of it as one. */ |
3b3b1423 | 668 | addr = inf_ptrace_register_u_offset (gdbarch, regnum, 0); |
8d4c1ba3 | 669 | if (addr == (CORE_ADDR)-1 |
3b3b1423 | 670 | || gdbarch_cannot_fetch_register (gdbarch, regnum)) |
10d6c8cd | 671 | { |
56be3814 | 672 | regcache_raw_supply (regcache, regnum, NULL); |
10d6c8cd DJ |
673 | return; |
674 | } | |
675 | ||
8785ced0 | 676 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 677 | separate processes. */ |
8785ced0 MK |
678 | pid = ptid_get_lwp (inferior_ptid); |
679 | if (pid == 0) | |
680 | pid = ptid_get_pid (inferior_ptid); | |
681 | ||
3b3b1423 | 682 | size = register_size (gdbarch, regnum); |
8785ced0 MK |
683 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
684 | buf = alloca (size); | |
685 | ||
10d6c8cd | 686 | /* Read the register contents from the inferior a chunk at a time. */ |
8785ced0 MK |
687 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
688 | { | |
689 | errno = 0; | |
f7dd0ed7 | 690 | buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, 0); |
8785ced0 | 691 | if (errno != 0) |
4b8a1a28 | 692 | error (_("Couldn't read register %s (#%d): %s."), |
3b3b1423 | 693 | gdbarch_register_name (gdbarch, regnum), |
c9f4d572 | 694 | regnum, safe_strerror (errno)); |
8785ced0 MK |
695 | |
696 | addr += sizeof (PTRACE_TYPE_RET); | |
697 | } | |
56be3814 | 698 | regcache_raw_supply (regcache, regnum, buf); |
8785ced0 MK |
699 | } |
700 | ||
701 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this | |
702 | for all registers. */ | |
703 | ||
704 | static void | |
56be3814 | 705 | inf_ptrace_fetch_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
706 | { |
707 | if (regnum == -1) | |
3b3b1423 UW |
708 | for (regnum = 0; |
709 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); | |
710 | regnum++) | |
56be3814 | 711 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 | 712 | else |
56be3814 | 713 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 MK |
714 | } |
715 | ||
716 | /* Store register REGNUM into the inferior. */ | |
717 | ||
718 | static void | |
56be3814 | 719 | inf_ptrace_store_register (const struct regcache *regcache, int regnum) |
8785ced0 | 720 | { |
3b3b1423 | 721 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
8785ced0 MK |
722 | CORE_ADDR addr; |
723 | size_t size; | |
724 | PTRACE_TYPE_RET *buf; | |
725 | int pid, i; | |
726 | ||
7714d83a | 727 | /* This isn't really an address, but ptrace thinks of it as one. */ |
3b3b1423 | 728 | addr = inf_ptrace_register_u_offset (gdbarch, regnum, 1); |
8d4c1ba3 | 729 | if (addr == (CORE_ADDR)-1 |
3b3b1423 | 730 | || gdbarch_cannot_store_register (gdbarch, regnum)) |
10d6c8cd DJ |
731 | return; |
732 | ||
8785ced0 | 733 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 734 | separate processes. */ |
8785ced0 MK |
735 | pid = ptid_get_lwp (inferior_ptid); |
736 | if (pid == 0) | |
737 | pid = ptid_get_pid (inferior_ptid); | |
738 | ||
3b3b1423 | 739 | size = register_size (gdbarch, regnum); |
8785ced0 MK |
740 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
741 | buf = alloca (size); | |
742 | ||
10d6c8cd | 743 | /* Write the register contents into the inferior a chunk at a time. */ |
56be3814 | 744 | regcache_raw_collect (regcache, regnum, buf); |
8785ced0 MK |
745 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
746 | { | |
747 | errno = 0; | |
f7dd0ed7 | 748 | ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]); |
8785ced0 | 749 | if (errno != 0) |
4b8a1a28 | 750 | error (_("Couldn't write register %s (#%d): %s."), |
3b3b1423 | 751 | gdbarch_register_name (gdbarch, regnum), |
c9f4d572 | 752 | regnum, safe_strerror (errno)); |
8785ced0 MK |
753 | |
754 | addr += sizeof (PTRACE_TYPE_RET); | |
755 | } | |
756 | } | |
757 | ||
758 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do | |
759 | this for all registers. */ | |
760 | ||
761 | void | |
56be3814 | 762 | inf_ptrace_store_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
763 | { |
764 | if (regnum == -1) | |
3b3b1423 UW |
765 | for (regnum = 0; |
766 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); | |
767 | regnum++) | |
56be3814 | 768 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 | 769 | else |
56be3814 | 770 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 MK |
771 | } |
772 | ||
773 | /* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be | |
774 | a function returning the offset within the user area where a | |
775 | particular register is stored. */ | |
776 | ||
777 | struct target_ops * | |
7714d83a UW |
778 | inf_ptrace_trad_target (CORE_ADDR (*register_u_offset) |
779 | (struct gdbarch *, int, int)) | |
8785ced0 MK |
780 | { |
781 | struct target_ops *t = inf_ptrace_target(); | |
782 | ||
783 | gdb_assert (register_u_offset); | |
784 | inf_ptrace_register_u_offset = register_u_offset; | |
785 | t->to_fetch_registers = inf_ptrace_fetch_registers; | |
786 | t->to_store_registers = inf_ptrace_store_registers; | |
787 | ||
5bf970f9 AC |
788 | return t; |
789 | } |