Commit | Line | Data |
---|---|---|
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 | ||
2c0b251b | 35 | #include "inf-ptrace.h" |
2c4a536d | 36 | #include "inf-child.h" |
af990527 | 37 | #include "gdbthread.h" |
2c4a536d | 38 | |
c7c14b96 MK |
39 | \f |
40 | ||
735f54b4 MK |
41 | #ifdef PT_GET_PROCESS_STATE |
42 | ||
43 | static int | |
ee057212 | 44 | inf_ptrace_follow_fork (struct target_ops *ops, int follow_child) |
735f54b4 MK |
45 | { |
46 | pid_t pid, fpid; | |
47 | ptrace_state_t pe; | |
4e1c45ea | 48 | struct thread_info *last_tp = NULL; |
735f54b4 MK |
49 | |
50 | /* FIXME: kettenis/20050720: This stuff should really be passed as | |
51 | an argument by our caller. */ | |
52 | { | |
53 | ptid_t ptid; | |
54 | struct target_waitstatus status; | |
55 | ||
56 | get_last_target_status (&ptid, &status); | |
57 | gdb_assert (status.kind == TARGET_WAITKIND_FORKED); | |
58 | ||
59 | pid = ptid_get_pid (ptid); | |
4e1c45ea | 60 | last_tp = find_thread_pid (ptid); |
735f54b4 MK |
61 | } |
62 | ||
63 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
64 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
65 | perror_with_name (("ptrace")); | |
66 | ||
67 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
68 | fpid = pe.pe_other_pid; | |
69 | ||
70 | if (follow_child) | |
71 | { | |
4e1c45ea PA |
72 | /* Copy user stepping state to the new inferior thread. */ |
73 | struct breakpoint *step_resume_breakpoint = last_tp->step_resume_breakpoint; | |
74 | CORE_ADDR step_range_start = last_tp->step_range_start; | |
75 | CORE_ADDR step_range_end = last_tp->step_range_end; | |
76 | struct frame_id step_frame_id = last_tp->step_frame_id; | |
77435e4c PA |
77 | int attach_flag = find_inferior_pid (pid)->attach_flag; |
78 | struct inferior *inf; | |
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. */ | |
77435e4c | 87 | remove_breakpoints (); |
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. */ | |
77435e4c PA |
99 | inf = add_inferior (fpid); |
100 | inf->attach_flag = attach_flag; | |
4e1c45ea PA |
101 | tp = add_thread_silent (inferior_ptid); |
102 | ||
103 | tp->step_resume_breakpoint = step_resume_breakpoint; | |
104 | tp->step_range_start = step_range_start; | |
105 | tp->step_range_end = step_range_end; | |
106 | tp->step_frame_id = step_frame_id; | |
107 | ||
108 | /* Reset breakpoints in the child as appropriate. */ | |
109 | follow_inferior_reset_breakpoints (); | |
735f54b4 MK |
110 | } |
111 | else | |
112 | { | |
113 | inferior_ptid = pid_to_ptid (pid); | |
114 | detach_breakpoints (fpid); | |
115 | ||
116 | if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
117 | perror_with_name (("ptrace")); | |
7f9f62ba | 118 | detach_inferior (pid); |
735f54b4 MK |
119 | } |
120 | ||
121 | return 0; | |
122 | } | |
123 | ||
124 | #endif /* PT_GET_PROCESS_STATE */ | |
125 | \f | |
126 | ||
4b8a1a28 | 127 | /* Prepare to be traced. */ |
5bf970f9 AC |
128 | |
129 | static void | |
c7c14b96 | 130 | inf_ptrace_me (void) |
5bf970f9 | 131 | { |
c7c14b96 | 132 | /* "Trace me, Dr. Memory!" */ |
4b8a1a28 | 133 | ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0); |
5bf970f9 AC |
134 | } |
135 | ||
136d6dae VP |
136 | /* Start a new inferior Unix child process. EXEC_FILE is the file to |
137 | run, ALLARGS is a string containing the arguments to the program. | |
138 | ENV is the environment vector to pass. If FROM_TTY is non-zero, be | |
139 | chatty about it. */ | |
5bf970f9 AC |
140 | |
141 | static void | |
136d6dae VP |
142 | inf_ptrace_create_inferior (struct target_ops *ops, |
143 | char *exec_file, char *allargs, char **env, | |
144 | int from_tty) | |
5bf970f9 | 145 | { |
136d6dae VP |
146 | int pid; |
147 | ||
148 | pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL, | |
149 | NULL, NULL); | |
150 | ||
151 | push_target (ops); | |
5bf970f9 | 152 | |
c7c14b96 MK |
153 | /* On some targets, there must be some explicit synchronization |
154 | between the parent and child processes after the debugger | |
155 | forks, and before the child execs the debuggee program. This | |
156 | call basically gives permission for the child to exec. */ | |
5bf970f9 | 157 | |
c7c14b96 | 158 | target_acknowledge_created_inferior (pid); |
5bf970f9 | 159 | |
c7c14b96 MK |
160 | /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will |
161 | be 1 or 2 depending on whether we're starting without or with a | |
162 | shell. */ | |
163 | startup_inferior (START_INFERIOR_TRAPS_EXPECTED); | |
164 | ||
165 | /* On some targets, there must be some explicit actions taken after | |
166 | the inferior has been started up. */ | |
167 | target_post_startup_inferior (pid_to_ptid (pid)); | |
5bf970f9 AC |
168 | } |
169 | ||
e4ef629d MK |
170 | #ifdef PT_GET_PROCESS_STATE |
171 | ||
172 | static void | |
173 | inf_ptrace_post_startup_inferior (ptid_t pid) | |
174 | { | |
175 | ptrace_event_t pe; | |
176 | ||
177 | /* Set the initial event mask. */ | |
178 | memset (&pe, 0, sizeof pe); | |
179 | pe.pe_set_event |= PTRACE_FORK; | |
180 | if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid), | |
181 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
182 | perror_with_name (("ptrace")); | |
183 | } | |
184 | ||
185 | #endif | |
186 | ||
4b8a1a28 MK |
187 | /* Clean up a rotting corpse of an inferior after it died. */ |
188 | ||
c7c14b96 | 189 | static void |
136d6dae | 190 | inf_ptrace_mourn_inferior (struct target_ops *ops) |
5bf970f9 | 191 | { |
4b8a1a28 MK |
192 | int status; |
193 | ||
194 | /* Wait just one more time to collect the inferior's exit status. | |
f010475d | 195 | Do not check whether this succeeds though, since we may be |
4b8a1a28 | 196 | dealing with a process that we attached to. Such a process will |
3d450bdd | 197 | only report its exit status to its original parent. */ |
4b8a1a28 MK |
198 | waitpid (ptid_get_pid (inferior_ptid), &status, 0); |
199 | ||
136d6dae | 200 | unpush_target (ops); |
c7c14b96 | 201 | generic_mourn_inferior (); |
5bf970f9 AC |
202 | } |
203 | ||
4b8a1a28 MK |
204 | /* Attach to the process specified by ARGS. If FROM_TTY is non-zero, |
205 | be chatty about it. */ | |
5bf970f9 AC |
206 | |
207 | static void | |
136d6dae | 208 | inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty) |
5bf970f9 AC |
209 | { |
210 | char *exec_file; | |
4b8a1a28 | 211 | pid_t pid; |
5bf970f9 | 212 | char *dummy; |
181e7f93 | 213 | struct inferior *inf; |
5bf970f9 AC |
214 | |
215 | if (!args) | |
e2e0b3e5 | 216 | error_no_arg (_("process-id to attach")); |
5bf970f9 AC |
217 | |
218 | dummy = args; | |
219 | pid = strtol (args, &dummy, 0); | |
f6ffd89b | 220 | /* Some targets don't set errno on errors, grrr! */ |
6e1e94ea | 221 | if (pid == 0 && args == dummy) |
8a3fe4f8 | 222 | error (_("Illegal process-id: %s."), args); |
5bf970f9 | 223 | |
f6ffd89b | 224 | if (pid == getpid ()) /* Trying to masturbate? */ |
8a3fe4f8 | 225 | error (_("I refuse to debug myself!")); |
5bf970f9 AC |
226 | |
227 | if (from_tty) | |
228 | { | |
4b8a1a28 | 229 | exec_file = get_exec_file (0); |
5bf970f9 AC |
230 | |
231 | if (exec_file) | |
a3f17187 | 232 | printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, |
5bf970f9 AC |
233 | target_pid_to_str (pid_to_ptid (pid))); |
234 | else | |
a3f17187 | 235 | printf_unfiltered (_("Attaching to %s\n"), |
5bf970f9 AC |
236 | target_pid_to_str (pid_to_ptid (pid))); |
237 | ||
238 | gdb_flush (gdb_stdout); | |
239 | } | |
240 | ||
6e1e94ea MK |
241 | #ifdef PT_ATTACH |
242 | errno = 0; | |
4b8a1a28 | 243 | ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0); |
6e1e94ea | 244 | if (errno != 0) |
e2e0b3e5 | 245 | perror_with_name (("ptrace")); |
6e1e94ea | 246 | #else |
8a3fe4f8 | 247 | error (_("This system does not support attaching to a process")); |
6e1e94ea | 248 | #endif |
5bf970f9 AC |
249 | |
250 | inferior_ptid = pid_to_ptid (pid); | |
af990527 | 251 | |
181e7f93 PA |
252 | inf = add_inferior (pid); |
253 | inf->attach_flag = 1; | |
7f9f62ba | 254 | |
af990527 PA |
255 | /* Always add a main thread. If some target extends the ptrace |
256 | target, it should decorate the ptid later with more info. */ | |
257 | add_thread_silent (inferior_ptid); | |
258 | ||
136d6dae | 259 | push_target(ops); |
5bf970f9 AC |
260 | } |
261 | ||
e4ef629d MK |
262 | #ifdef PT_GET_PROCESS_STATE |
263 | ||
264 | void | |
265 | inf_ptrace_post_attach (int pid) | |
266 | { | |
267 | ptrace_event_t pe; | |
268 | ||
269 | /* Set the initial event mask. */ | |
270 | memset (&pe, 0, sizeof pe); | |
271 | pe.pe_set_event |= PTRACE_FORK; | |
272 | if (ptrace (PT_SET_EVENT_MASK, pid, | |
273 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
274 | perror_with_name (("ptrace")); | |
275 | } | |
276 | ||
277 | #endif | |
278 | ||
4b8a1a28 | 279 | /* Detach from the inferior, optionally passing it the signal |
f010475d | 280 | specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ |
5bf970f9 AC |
281 | |
282 | static void | |
136d6dae | 283 | inf_ptrace_detach (struct target_ops *ops, char *args, int from_tty) |
5bf970f9 | 284 | { |
4b8a1a28 | 285 | pid_t pid = ptid_get_pid (inferior_ptid); |
6e1e94ea | 286 | int sig = 0; |
5bf970f9 AC |
287 | |
288 | if (from_tty) | |
289 | { | |
290 | char *exec_file = get_exec_file (0); | |
291 | if (exec_file == 0) | |
292 | exec_file = ""; | |
a3f17187 | 293 | printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, |
5bf970f9 AC |
294 | target_pid_to_str (pid_to_ptid (pid))); |
295 | gdb_flush (gdb_stdout); | |
296 | } | |
297 | if (args) | |
6e1e94ea | 298 | sig = atoi (args); |
5bf970f9 | 299 | |
6e1e94ea | 300 | #ifdef PT_DETACH |
4b8a1a28 | 301 | /* We'd better not have left any breakpoints in the program or it'll |
f010475d | 302 | die when it hits one. Also note that this may only work if we |
4b8a1a28 MK |
303 | previously attached to the inferior. It *might* work if we |
304 | started the process ourselves. */ | |
6e1e94ea | 305 | errno = 0; |
4b8a1a28 | 306 | ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig); |
6e1e94ea | 307 | if (errno != 0) |
e2e0b3e5 | 308 | perror_with_name (("ptrace")); |
6e1e94ea | 309 | #else |
8a3fe4f8 | 310 | error (_("This system does not support detaching from a process")); |
6e1e94ea | 311 | #endif |
5bf970f9 AC |
312 | |
313 | inferior_ptid = null_ptid; | |
7f9f62ba | 314 | detach_inferior (pid); |
7a7d3353 PA |
315 | |
316 | if (!have_inferiors ()) | |
317 | unpush_target (ops); | |
5bf970f9 AC |
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 | 388 | static ptid_t |
117de6a9 PA |
389 | inf_ptrace_wait (struct target_ops *ops, |
390 | ptid_t ptid, struct target_waitstatus *ourstatus) | |
5bf970f9 | 391 | { |
4b8a1a28 MK |
392 | pid_t pid; |
393 | int status, save_errno; | |
5bf970f9 | 394 | |
c7c14b96 MK |
395 | do |
396 | { | |
4b8a1a28 | 397 | set_sigint_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_sigint_trap (); |
5bf970f9 | 407 | |
c7c14b96 MK |
408 | if (pid == -1) |
409 | { | |
c7c14b96 | 410 | fprintf_unfiltered (gdb_stderr, |
4b8a1a28 | 411 | _("Child process unexpectedly missing: %s.\n"), |
c7c14b96 MK |
412 | safe_strerror (save_errno)); |
413 | ||
414 | /* Claim it exited with unknown signal. */ | |
415 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
416 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
fb66883a | 417 | return inferior_ptid; |
c7c14b96 MK |
418 | } |
419 | ||
4b8a1a28 MK |
420 | /* Ignore terminated detached child processes. */ |
421 | if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid)) | |
422 | pid = -1; | |
c7c14b96 | 423 | } |
4b8a1a28 | 424 | while (pid == -1); |
c7c14b96 | 425 | |
735f54b4 MK |
426 | #ifdef PT_GET_PROCESS_STATE |
427 | if (WIFSTOPPED (status)) | |
428 | { | |
429 | ptrace_state_t pe; | |
430 | pid_t fpid; | |
431 | ||
432 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
433 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
434 | perror_with_name (("ptrace")); | |
435 | ||
436 | switch (pe.pe_report_event) | |
437 | { | |
438 | case PTRACE_FORK: | |
439 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
3a3e9ee3 | 440 | ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid); |
735f54b4 MK |
441 | |
442 | /* Make sure the other end of the fork is stopped too. */ | |
443 | fpid = waitpid (pe.pe_other_pid, &status, 0); | |
444 | if (fpid == -1) | |
445 | perror_with_name (("waitpid")); | |
446 | ||
447 | if (ptrace (PT_GET_PROCESS_STATE, fpid, | |
448 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
449 | perror_with_name (("ptrace")); | |
450 | ||
451 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
452 | gdb_assert (pe.pe_other_pid == pid); | |
453 | if (fpid == ptid_get_pid (inferior_ptid)) | |
454 | { | |
3a3e9ee3 | 455 | ourstatus->value.related_pid = pid_to_ptid (pe.pe_other_pid); |
735f54b4 MK |
456 | return pid_to_ptid (fpid); |
457 | } | |
458 | ||
459 | return pid_to_ptid (pid); | |
460 | } | |
461 | } | |
462 | #endif | |
463 | ||
c7c14b96 MK |
464 | store_waitstatus (ourstatus, status); |
465 | return pid_to_ptid (pid); | |
5bf970f9 AC |
466 | } |
467 | ||
4b8a1a28 MK |
468 | /* Attempt a transfer all LEN bytes starting at OFFSET between the |
469 | inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer. | |
470 | Return the number of bytes actually transferred. */ | |
5bf970f9 AC |
471 | |
472 | static LONGEST | |
473 | inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, | |
961cb7b5 MK |
474 | const char *annex, gdb_byte *readbuf, |
475 | const gdb_byte *writebuf, | |
476 | ULONGEST offset, LONGEST len) | |
5bf970f9 | 477 | { |
4b8a1a28 MK |
478 | pid_t pid = ptid_get_pid (inferior_ptid); |
479 | ||
5bf970f9 AC |
480 | switch (object) |
481 | { | |
482 | case TARGET_OBJECT_MEMORY: | |
f929a579 AC |
483 | #ifdef PT_IO |
484 | /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO | |
485 | request that promises to be much more efficient in reading | |
486 | and writing data in the traced process's address space. */ | |
487 | { | |
488 | struct ptrace_io_desc piod; | |
4b8a1a28 | 489 | |
f929a579 | 490 | /* NOTE: We assume that there are no distinct address spaces |
b457b3dd MK |
491 | for instruction and data. However, on OpenBSD 3.9 and |
492 | later, PIOD_WRITE_D doesn't allow changing memory that's | |
493 | mapped read-only. Since most code segments will be | |
494 | read-only, using PIOD_WRITE_D will prevent us from | |
495 | inserting breakpoints, so we use PIOD_WRITE_I instead. */ | |
496 | piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D; | |
f929a579 AC |
497 | piod.piod_addr = writebuf ? (void *) writebuf : readbuf; |
498 | piod.piod_offs = (void *) (long) offset; | |
499 | piod.piod_len = len; | |
500 | ||
501 | errno = 0; | |
4b8a1a28 | 502 | if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0) |
f929a579 AC |
503 | /* Return the actual number of bytes read or written. */ |
504 | return piod.piod_len; | |
505 | /* If the PT_IO request is somehow not supported, fallback on | |
506 | using PT_WRITE_D/PT_READ_D. Otherwise we will return zero | |
507 | to indicate failure. */ | |
508 | if (errno != EINVAL) | |
509 | return 0; | |
510 | } | |
511 | #endif | |
512 | { | |
513 | union | |
514 | { | |
515 | PTRACE_TYPE_RET word; | |
4b8a1a28 | 516 | gdb_byte byte[sizeof (PTRACE_TYPE_RET)]; |
f929a579 AC |
517 | } buffer; |
518 | ULONGEST rounded_offset; | |
519 | LONGEST partial_len; | |
4b8a1a28 | 520 | |
cb85a953 AC |
521 | /* Round the start offset down to the next long word |
522 | boundary. */ | |
f929a579 | 523 | rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); |
4b8a1a28 | 524 | |
cb85a953 AC |
525 | /* Since ptrace will transfer a single word starting at that |
526 | rounded_offset the partial_len needs to be adjusted down to | |
527 | that (remember this function only does a single transfer). | |
528 | Should the required length be even less, adjust it down | |
529 | again. */ | |
530 | partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset; | |
531 | if (partial_len > len) | |
f929a579 | 532 | partial_len = len; |
4b8a1a28 | 533 | |
f929a579 AC |
534 | if (writebuf) |
535 | { | |
cb85a953 AC |
536 | /* If OFFSET:PARTIAL_LEN is smaller than |
537 | ROUNDED_OFFSET:WORDSIZE then a read/modify write will | |
538 | be needed. Read in the entire word. */ | |
f929a579 | 539 | if (rounded_offset < offset |
cb85a953 AC |
540 | || (offset + partial_len |
541 | < rounded_offset + sizeof (PTRACE_TYPE_RET))) | |
f929a579 | 542 | /* Need part of initial word -- fetch it. */ |
4b8a1a28 | 543 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
544 | (PTRACE_TYPE_ARG3)(uintptr_t) |
545 | rounded_offset, 0); | |
4b8a1a28 | 546 | |
f929a579 AC |
547 | /* Copy data to be written over corresponding part of |
548 | buffer. */ | |
f6ffd89b MK |
549 | memcpy (buffer.byte + (offset - rounded_offset), |
550 | writebuf, partial_len); | |
4b8a1a28 | 551 | |
f929a579 | 552 | errno = 0; |
4b8a1a28 | 553 | ptrace (PT_WRITE_D, pid, |
f7dd0ed7 UW |
554 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
555 | buffer.word); | |
f929a579 AC |
556 | if (errno) |
557 | { | |
558 | /* Using the appropriate one (I or D) is necessary for | |
559 | Gould NP1, at least. */ | |
560 | errno = 0; | |
4b8a1a28 | 561 | ptrace (PT_WRITE_I, pid, |
f7dd0ed7 UW |
562 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
563 | buffer.word); | |
f929a579 AC |
564 | if (errno) |
565 | return 0; | |
566 | } | |
567 | } | |
4b8a1a28 | 568 | |
f929a579 AC |
569 | if (readbuf) |
570 | { | |
571 | errno = 0; | |
4b8a1a28 | 572 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
573 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
574 | 0); | |
f929a579 AC |
575 | if (errno) |
576 | return 0; | |
577 | /* Copy appropriate bytes out of the buffer. */ | |
578 | memcpy (readbuf, buffer.byte + (offset - rounded_offset), | |
579 | partial_len); | |
580 | } | |
4b8a1a28 | 581 | |
f929a579 AC |
582 | return partial_len; |
583 | } | |
5bf970f9 AC |
584 | |
585 | case TARGET_OBJECT_UNWIND_TABLE: | |
586 | return -1; | |
587 | ||
588 | case TARGET_OBJECT_AUXV: | |
589 | return -1; | |
590 | ||
591 | case TARGET_OBJECT_WCOOKIE: | |
592 | return -1; | |
593 | ||
594 | default: | |
595 | return -1; | |
596 | } | |
597 | } | |
598 | ||
4b8a1a28 | 599 | /* Return non-zero if the thread specified by PTID is alive. */ |
c7c14b96 MK |
600 | |
601 | static int | |
602 | inf_ptrace_thread_alive (ptid_t ptid) | |
603 | { | |
4b8a1a28 MK |
604 | /* ??? Is kill the right way to do this? */ |
605 | return (kill (ptid_get_pid (ptid), 0) != -1); | |
c7c14b96 MK |
606 | } |
607 | ||
608 | /* Print status information about what we're accessing. */ | |
609 | ||
610 | static void | |
611 | inf_ptrace_files_info (struct target_ops *ignore) | |
612 | { | |
181e7f93 PA |
613 | struct inferior *inf = current_inferior (); |
614 | ||
4b8a1a28 | 615 | printf_filtered (_("\tUsing the running image of %s %s.\n"), |
181e7f93 | 616 | inf->attach_flag ? "attached" : "child", |
4b8a1a28 | 617 | target_pid_to_str (inferior_ptid)); |
5bf970f9 AC |
618 | } |
619 | ||
117de6a9 PA |
620 | static char * |
621 | inf_ptrace_pid_to_str (struct target_ops *ops, ptid_t ptid) | |
622 | { | |
623 | return normal_pid_to_str (ptid); | |
624 | } | |
625 | ||
8785ced0 MK |
626 | /* Create a prototype ptrace target. The client can override it with |
627 | local methods. */ | |
628 | ||
5bf970f9 AC |
629 | struct target_ops * |
630 | inf_ptrace_target (void) | |
631 | { | |
632 | struct target_ops *t = inf_child_target (); | |
8785ced0 | 633 | |
5bf970f9 | 634 | t->to_attach = inf_ptrace_attach; |
5bf970f9 AC |
635 | t->to_detach = inf_ptrace_detach; |
636 | t->to_resume = inf_ptrace_resume; | |
637 | t->to_wait = inf_ptrace_wait; | |
5bf970f9 | 638 | t->to_files_info = inf_ptrace_files_info; |
4b8a1a28 | 639 | t->to_kill = inf_ptrace_kill; |
5bf970f9 | 640 | t->to_create_inferior = inf_ptrace_create_inferior; |
735f54b4 MK |
641 | #ifdef PT_GET_PROCESS_STATE |
642 | t->to_follow_fork = inf_ptrace_follow_fork; | |
e4ef629d MK |
643 | t->to_post_startup_inferior = inf_ptrace_post_startup_inferior; |
644 | t->to_post_attach = inf_ptrace_post_attach; | |
735f54b4 | 645 | #endif |
5bf970f9 | 646 | t->to_mourn_inferior = inf_ptrace_mourn_inferior; |
5bf970f9 | 647 | t->to_thread_alive = inf_ptrace_thread_alive; |
117de6a9 | 648 | t->to_pid_to_str = inf_ptrace_pid_to_str; |
5bf970f9 | 649 | t->to_stop = inf_ptrace_stop; |
c7c14b96 | 650 | t->to_xfer_partial = inf_ptrace_xfer_partial; |
8785ced0 MK |
651 | |
652 | return t; | |
653 | } | |
654 | \f | |
655 | ||
4b8a1a28 | 656 | /* Pointer to a function that returns the offset within the user area |
8785ced0 | 657 | where a particular register is stored. */ |
7714d83a | 658 | static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int); |
8785ced0 MK |
659 | |
660 | /* Fetch register REGNUM from the inferior. */ | |
661 | ||
662 | static void | |
56be3814 | 663 | inf_ptrace_fetch_register (struct regcache *regcache, int regnum) |
8785ced0 | 664 | { |
3b3b1423 | 665 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
8785ced0 MK |
666 | CORE_ADDR addr; |
667 | size_t size; | |
668 | PTRACE_TYPE_RET *buf; | |
669 | int pid, i; | |
670 | ||
7714d83a | 671 | /* This isn't really an address, but ptrace thinks of it as one. */ |
3b3b1423 | 672 | addr = inf_ptrace_register_u_offset (gdbarch, regnum, 0); |
8d4c1ba3 | 673 | if (addr == (CORE_ADDR)-1 |
3b3b1423 | 674 | || gdbarch_cannot_fetch_register (gdbarch, regnum)) |
10d6c8cd | 675 | { |
56be3814 | 676 | regcache_raw_supply (regcache, regnum, NULL); |
10d6c8cd DJ |
677 | return; |
678 | } | |
679 | ||
8785ced0 | 680 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 681 | separate processes. */ |
8785ced0 MK |
682 | pid = ptid_get_lwp (inferior_ptid); |
683 | if (pid == 0) | |
684 | pid = ptid_get_pid (inferior_ptid); | |
685 | ||
3b3b1423 | 686 | size = register_size (gdbarch, regnum); |
8785ced0 MK |
687 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
688 | buf = alloca (size); | |
689 | ||
10d6c8cd | 690 | /* Read the register contents from the inferior a chunk at a time. */ |
8785ced0 MK |
691 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
692 | { | |
693 | errno = 0; | |
f7dd0ed7 | 694 | buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, 0); |
8785ced0 | 695 | if (errno != 0) |
4b8a1a28 | 696 | error (_("Couldn't read register %s (#%d): %s."), |
3b3b1423 | 697 | gdbarch_register_name (gdbarch, regnum), |
c9f4d572 | 698 | regnum, safe_strerror (errno)); |
8785ced0 MK |
699 | |
700 | addr += sizeof (PTRACE_TYPE_RET); | |
701 | } | |
56be3814 | 702 | regcache_raw_supply (regcache, regnum, buf); |
8785ced0 MK |
703 | } |
704 | ||
705 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this | |
706 | for all registers. */ | |
707 | ||
708 | static void | |
56be3814 | 709 | inf_ptrace_fetch_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
710 | { |
711 | if (regnum == -1) | |
3b3b1423 UW |
712 | for (regnum = 0; |
713 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); | |
714 | regnum++) | |
56be3814 | 715 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 | 716 | else |
56be3814 | 717 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 MK |
718 | } |
719 | ||
720 | /* Store register REGNUM into the inferior. */ | |
721 | ||
722 | static void | |
56be3814 | 723 | inf_ptrace_store_register (const struct regcache *regcache, int regnum) |
8785ced0 | 724 | { |
3b3b1423 | 725 | struct gdbarch *gdbarch = get_regcache_arch (regcache); |
8785ced0 MK |
726 | CORE_ADDR addr; |
727 | size_t size; | |
728 | PTRACE_TYPE_RET *buf; | |
729 | int pid, i; | |
730 | ||
7714d83a | 731 | /* This isn't really an address, but ptrace thinks of it as one. */ |
3b3b1423 | 732 | addr = inf_ptrace_register_u_offset (gdbarch, regnum, 1); |
8d4c1ba3 | 733 | if (addr == (CORE_ADDR)-1 |
3b3b1423 | 734 | || gdbarch_cannot_store_register (gdbarch, regnum)) |
10d6c8cd DJ |
735 | return; |
736 | ||
8785ced0 | 737 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 738 | separate processes. */ |
8785ced0 MK |
739 | pid = ptid_get_lwp (inferior_ptid); |
740 | if (pid == 0) | |
741 | pid = ptid_get_pid (inferior_ptid); | |
742 | ||
3b3b1423 | 743 | size = register_size (gdbarch, regnum); |
8785ced0 MK |
744 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
745 | buf = alloca (size); | |
746 | ||
10d6c8cd | 747 | /* Write the register contents into the inferior a chunk at a time. */ |
56be3814 | 748 | regcache_raw_collect (regcache, regnum, buf); |
8785ced0 MK |
749 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
750 | { | |
751 | errno = 0; | |
f7dd0ed7 | 752 | ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]); |
8785ced0 | 753 | if (errno != 0) |
4b8a1a28 | 754 | error (_("Couldn't write register %s (#%d): %s."), |
3b3b1423 | 755 | gdbarch_register_name (gdbarch, regnum), |
c9f4d572 | 756 | regnum, safe_strerror (errno)); |
8785ced0 MK |
757 | |
758 | addr += sizeof (PTRACE_TYPE_RET); | |
759 | } | |
760 | } | |
761 | ||
762 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do | |
763 | this for all registers. */ | |
764 | ||
2c0b251b | 765 | static void |
56be3814 | 766 | inf_ptrace_store_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
767 | { |
768 | if (regnum == -1) | |
3b3b1423 UW |
769 | for (regnum = 0; |
770 | regnum < gdbarch_num_regs (get_regcache_arch (regcache)); | |
771 | regnum++) | |
56be3814 | 772 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 | 773 | else |
56be3814 | 774 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 MK |
775 | } |
776 | ||
777 | /* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be | |
778 | a function returning the offset within the user area where a | |
779 | particular register is stored. */ | |
780 | ||
781 | struct target_ops * | |
7714d83a UW |
782 | inf_ptrace_trad_target (CORE_ADDR (*register_u_offset) |
783 | (struct gdbarch *, int, int)) | |
8785ced0 MK |
784 | { |
785 | struct target_ops *t = inf_ptrace_target(); | |
786 | ||
787 | gdb_assert (register_u_offset); | |
788 | inf_ptrace_register_u_offset = register_u_offset; | |
789 | t->to_fetch_registers = inf_ptrace_fetch_registers; | |
790 | t->to_store_registers = inf_ptrace_store_registers; | |
791 | ||
5bf970f9 AC |
792 | return t; |
793 | } |