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