Commit | Line | Data |
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2c4a536d | 1 | /* Low-level child interface to ptrace. |
5bf970f9 | 2 | |
6aba47ca DJ |
3 | Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, |
4 | 1999, 2000, 2001, 2002, 2004, 2005, 2006, 2007 | |
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 | |
f7dd0ed7 | 29 | #include "gdb_stdint.h" |
8785ced0 | 30 | #include "gdb_assert.h" |
2c4a536d MK |
31 | #include "gdb_string.h" |
32 | #include "gdb_ptrace.h" | |
34a17005 | 33 | #include "gdb_wait.h" |
5bf970f9 AC |
34 | #include <signal.h> |
35 | ||
2c4a536d MK |
36 | #include "inf-child.h" |
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; | |
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); | |
60 | } | |
61 | ||
62 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
63 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
64 | perror_with_name (("ptrace")); | |
65 | ||
66 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
67 | fpid = pe.pe_other_pid; | |
68 | ||
69 | if (follow_child) | |
70 | { | |
71 | inferior_ptid = pid_to_ptid (fpid); | |
72 | detach_breakpoints (pid); | |
73 | ||
74 | /* Reset breakpoints in the child as appropriate. */ | |
75 | follow_inferior_reset_breakpoints (); | |
76 | ||
77 | if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
78 | perror_with_name (("ptrace")); | |
79 | } | |
80 | else | |
81 | { | |
82 | inferior_ptid = pid_to_ptid (pid); | |
83 | detach_breakpoints (fpid); | |
84 | ||
85 | if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
86 | perror_with_name (("ptrace")); | |
87 | } | |
88 | ||
89 | return 0; | |
90 | } | |
91 | ||
92 | #endif /* PT_GET_PROCESS_STATE */ | |
93 | \f | |
94 | ||
4b8a1a28 | 95 | /* Prepare to be traced. */ |
5bf970f9 AC |
96 | |
97 | static void | |
c7c14b96 | 98 | inf_ptrace_me (void) |
5bf970f9 | 99 | { |
c7c14b96 | 100 | /* "Trace me, Dr. Memory!" */ |
4b8a1a28 | 101 | ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0); |
5bf970f9 AC |
102 | } |
103 | ||
4b8a1a28 | 104 | /* Start tracing PID. */ |
5bf970f9 AC |
105 | |
106 | static void | |
c7c14b96 | 107 | inf_ptrace_him (int pid) |
5bf970f9 | 108 | { |
c7c14b96 | 109 | push_target (ptrace_ops_hack); |
5bf970f9 | 110 | |
c7c14b96 MK |
111 | /* On some targets, there must be some explicit synchronization |
112 | between the parent and child processes after the debugger | |
113 | forks, and before the child execs the debuggee program. This | |
114 | call basically gives permission for the child to exec. */ | |
5bf970f9 | 115 | |
c7c14b96 | 116 | target_acknowledge_created_inferior (pid); |
5bf970f9 | 117 | |
c7c14b96 MK |
118 | /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will |
119 | be 1 or 2 depending on whether we're starting without or with a | |
120 | shell. */ | |
121 | startup_inferior (START_INFERIOR_TRAPS_EXPECTED); | |
122 | ||
123 | /* On some targets, there must be some explicit actions taken after | |
124 | the inferior has been started up. */ | |
125 | target_post_startup_inferior (pid_to_ptid (pid)); | |
5bf970f9 AC |
126 | } |
127 | ||
4b8a1a28 MK |
128 | /* Start a new inferior Unix child process. EXEC_FILE is the file to |
129 | run, ALLARGS is a string containing the arguments to the program. | |
130 | ENV is the environment vector to pass. If FROM_TTY is non-zero, be | |
131 | chatty about it. */ | |
5bf970f9 | 132 | |
c7c14b96 MK |
133 | static void |
134 | inf_ptrace_create_inferior (char *exec_file, char *allargs, char **env, | |
135 | int from_tty) | |
5bf970f9 | 136 | { |
c7c14b96 MK |
137 | fork_inferior (exec_file, allargs, env, inf_ptrace_me, inf_ptrace_him, |
138 | NULL, NULL); | |
5bf970f9 AC |
139 | } |
140 | ||
e4ef629d MK |
141 | #ifdef PT_GET_PROCESS_STATE |
142 | ||
143 | static void | |
144 | inf_ptrace_post_startup_inferior (ptid_t pid) | |
145 | { | |
146 | ptrace_event_t pe; | |
147 | ||
148 | /* Set the initial event mask. */ | |
149 | memset (&pe, 0, sizeof pe); | |
150 | pe.pe_set_event |= PTRACE_FORK; | |
151 | if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid), | |
152 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
153 | perror_with_name (("ptrace")); | |
154 | } | |
155 | ||
156 | #endif | |
157 | ||
4b8a1a28 MK |
158 | /* Clean up a rotting corpse of an inferior after it died. */ |
159 | ||
c7c14b96 MK |
160 | static void |
161 | inf_ptrace_mourn_inferior (void) | |
5bf970f9 | 162 | { |
4b8a1a28 MK |
163 | int status; |
164 | ||
165 | /* Wait just one more time to collect the inferior's exit status. | |
f010475d | 166 | Do not check whether this succeeds though, since we may be |
4b8a1a28 | 167 | dealing with a process that we attached to. Such a process will |
3d450bdd | 168 | only report its exit status to its original parent. */ |
4b8a1a28 MK |
169 | waitpid (ptid_get_pid (inferior_ptid), &status, 0); |
170 | ||
c7c14b96 MK |
171 | unpush_target (ptrace_ops_hack); |
172 | generic_mourn_inferior (); | |
5bf970f9 AC |
173 | } |
174 | ||
4b8a1a28 MK |
175 | /* Attach to the process specified by ARGS. If FROM_TTY is non-zero, |
176 | be chatty about it. */ | |
5bf970f9 AC |
177 | |
178 | static void | |
179 | inf_ptrace_attach (char *args, int from_tty) | |
180 | { | |
181 | char *exec_file; | |
4b8a1a28 | 182 | pid_t pid; |
5bf970f9 AC |
183 | char *dummy; |
184 | ||
185 | if (!args) | |
e2e0b3e5 | 186 | error_no_arg (_("process-id to attach")); |
5bf970f9 AC |
187 | |
188 | dummy = args; | |
189 | pid = strtol (args, &dummy, 0); | |
f6ffd89b | 190 | /* Some targets don't set errno on errors, grrr! */ |
6e1e94ea | 191 | if (pid == 0 && args == dummy) |
8a3fe4f8 | 192 | error (_("Illegal process-id: %s."), args); |
5bf970f9 | 193 | |
f6ffd89b | 194 | if (pid == getpid ()) /* Trying to masturbate? */ |
8a3fe4f8 | 195 | error (_("I refuse to debug myself!")); |
5bf970f9 AC |
196 | |
197 | if (from_tty) | |
198 | { | |
4b8a1a28 | 199 | exec_file = get_exec_file (0); |
5bf970f9 AC |
200 | |
201 | if (exec_file) | |
a3f17187 | 202 | printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, |
5bf970f9 AC |
203 | target_pid_to_str (pid_to_ptid (pid))); |
204 | else | |
a3f17187 | 205 | printf_unfiltered (_("Attaching to %s\n"), |
5bf970f9 AC |
206 | target_pid_to_str (pid_to_ptid (pid))); |
207 | ||
208 | gdb_flush (gdb_stdout); | |
209 | } | |
210 | ||
6e1e94ea MK |
211 | #ifdef PT_ATTACH |
212 | errno = 0; | |
4b8a1a28 | 213 | ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0); |
6e1e94ea | 214 | if (errno != 0) |
e2e0b3e5 | 215 | perror_with_name (("ptrace")); |
6e1e94ea MK |
216 | attach_flag = 1; |
217 | #else | |
8a3fe4f8 | 218 | error (_("This system does not support attaching to a process")); |
6e1e94ea | 219 | #endif |
5bf970f9 AC |
220 | |
221 | inferior_ptid = pid_to_ptid (pid); | |
222 | push_target (ptrace_ops_hack); | |
223 | } | |
224 | ||
e4ef629d MK |
225 | #ifdef PT_GET_PROCESS_STATE |
226 | ||
227 | void | |
228 | inf_ptrace_post_attach (int pid) | |
229 | { | |
230 | ptrace_event_t pe; | |
231 | ||
232 | /* Set the initial event mask. */ | |
233 | memset (&pe, 0, sizeof pe); | |
234 | pe.pe_set_event |= PTRACE_FORK; | |
235 | if (ptrace (PT_SET_EVENT_MASK, pid, | |
236 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
237 | perror_with_name (("ptrace")); | |
238 | } | |
239 | ||
240 | #endif | |
241 | ||
4b8a1a28 | 242 | /* Detach from the inferior, optionally passing it the signal |
f010475d | 243 | specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ |
5bf970f9 AC |
244 | |
245 | static void | |
246 | inf_ptrace_detach (char *args, int from_tty) | |
247 | { | |
4b8a1a28 | 248 | pid_t pid = ptid_get_pid (inferior_ptid); |
6e1e94ea | 249 | int sig = 0; |
5bf970f9 AC |
250 | |
251 | if (from_tty) | |
252 | { | |
253 | char *exec_file = get_exec_file (0); | |
254 | if (exec_file == 0) | |
255 | exec_file = ""; | |
a3f17187 | 256 | printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, |
5bf970f9 AC |
257 | target_pid_to_str (pid_to_ptid (pid))); |
258 | gdb_flush (gdb_stdout); | |
259 | } | |
260 | if (args) | |
6e1e94ea | 261 | sig = atoi (args); |
5bf970f9 | 262 | |
6e1e94ea | 263 | #ifdef PT_DETACH |
4b8a1a28 | 264 | /* We'd better not have left any breakpoints in the program or it'll |
f010475d | 265 | die when it hits one. Also note that this may only work if we |
4b8a1a28 MK |
266 | previously attached to the inferior. It *might* work if we |
267 | started the process ourselves. */ | |
6e1e94ea | 268 | errno = 0; |
4b8a1a28 | 269 | ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig); |
6e1e94ea | 270 | if (errno != 0) |
e2e0b3e5 | 271 | perror_with_name (("ptrace")); |
6e1e94ea MK |
272 | attach_flag = 0; |
273 | #else | |
8a3fe4f8 | 274 | error (_("This system does not support detaching from a process")); |
6e1e94ea | 275 | #endif |
5bf970f9 AC |
276 | |
277 | inferior_ptid = null_ptid; | |
278 | unpush_target (ptrace_ops_hack); | |
279 | } | |
280 | ||
4b8a1a28 MK |
281 | /* Kill the inferior. */ |
282 | ||
5bf970f9 | 283 | static void |
4b8a1a28 | 284 | inf_ptrace_kill (void) |
5bf970f9 | 285 | { |
4b8a1a28 | 286 | pid_t pid = ptid_get_pid (inferior_ptid); |
c7c14b96 | 287 | int status; |
c7c14b96 MK |
288 | |
289 | if (pid == 0) | |
290 | return; | |
291 | ||
4b8a1a28 MK |
292 | ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0); |
293 | waitpid (pid, &status, 0); | |
294 | ||
c7c14b96 | 295 | target_mourn_inferior (); |
5bf970f9 AC |
296 | } |
297 | ||
4b8a1a28 | 298 | /* Stop the inferior. */ |
c7c14b96 | 299 | |
5bf970f9 | 300 | static void |
c7c14b96 | 301 | inf_ptrace_stop (void) |
5bf970f9 | 302 | { |
4b8a1a28 MK |
303 | /* Send a SIGINT to the process group. This acts just like the user |
304 | typed a ^C on the controlling terminal. Note that using a | |
305 | negative process number in kill() is a System V-ism. The proper | |
306 | BSD interface is killpg(). However, all modern BSDs support the | |
307 | System V interface too. */ | |
c7c14b96 | 308 | kill (-inferior_process_group, SIGINT); |
5bf970f9 AC |
309 | } |
310 | ||
4b8a1a28 MK |
311 | /* Resume execution of thread PTID, or all threads if PTID is -1. If |
312 | STEP is nonzero, single-step it. If SIGNAL is nonzero, give it | |
313 | that signal. */ | |
5bf970f9 AC |
314 | |
315 | static void | |
c7c14b96 | 316 | inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal) |
5bf970f9 | 317 | { |
4b8a1a28 | 318 | pid_t pid = ptid_get_pid (ptid); |
c7c14b96 | 319 | int request = PT_CONTINUE; |
c7c14b96 MK |
320 | |
321 | if (pid == -1) | |
4b8a1a28 MK |
322 | /* Resume all threads. Traditionally ptrace() only supports |
323 | single-threaded processes, so simply resume the inferior. */ | |
324 | pid = ptid_get_pid (inferior_ptid); | |
c7c14b96 MK |
325 | |
326 | if (step) | |
327 | { | |
328 | /* If this system does not support PT_STEP, a higher level | |
329 | function will have called single_step() to transmute the step | |
330 | request into a continue request (by setting breakpoints on | |
331 | all possible successor instructions), so we don't have to | |
332 | worry about that here. */ | |
333 | request = PT_STEP; | |
334 | } | |
335 | ||
336 | /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from | |
337 | where it was. If GDB wanted it to start some other way, we have | |
4b8a1a28 | 338 | already written a new program counter value to the child. */ |
c7c14b96 | 339 | errno = 0; |
4b8a1a28 | 340 | ptrace (request, pid, (PTRACE_TYPE_ARG3)1, target_signal_to_host (signal)); |
c7c14b96 MK |
341 | if (errno != 0) |
342 | perror_with_name (("ptrace")); | |
5bf970f9 AC |
343 | } |
344 | ||
4b8a1a28 MK |
345 | /* Wait for the child specified by PTID to do something. Return the |
346 | process ID of the child, or MINUS_ONE_PTID in case of error; store | |
347 | the status in *OURSTATUS. */ | |
5bf970f9 | 348 | |
c7c14b96 MK |
349 | static ptid_t |
350 | inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
5bf970f9 | 351 | { |
4b8a1a28 MK |
352 | pid_t pid; |
353 | int status, save_errno; | |
5bf970f9 | 354 | |
c7c14b96 MK |
355 | do |
356 | { | |
4b8a1a28 | 357 | set_sigint_trap (); |
c7c14b96 | 358 | set_sigio_trap (); |
5bf970f9 | 359 | |
4b8a1a28 MK |
360 | do |
361 | { | |
362 | pid = waitpid (ptid_get_pid (ptid), &status, 0); | |
363 | save_errno = errno; | |
364 | } | |
365 | while (pid == -1 && errno == EINTR); | |
5bf970f9 | 366 | |
c7c14b96 | 367 | clear_sigio_trap (); |
c7c14b96 | 368 | clear_sigint_trap (); |
5bf970f9 | 369 | |
c7c14b96 MK |
370 | if (pid == -1) |
371 | { | |
c7c14b96 | 372 | fprintf_unfiltered (gdb_stderr, |
4b8a1a28 | 373 | _("Child process unexpectedly missing: %s.\n"), |
c7c14b96 MK |
374 | safe_strerror (save_errno)); |
375 | ||
376 | /* Claim it exited with unknown signal. */ | |
377 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
378 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
4b8a1a28 | 379 | return minus_one_ptid; |
c7c14b96 MK |
380 | } |
381 | ||
4b8a1a28 MK |
382 | /* Ignore terminated detached child processes. */ |
383 | if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid)) | |
384 | pid = -1; | |
c7c14b96 | 385 | } |
4b8a1a28 | 386 | while (pid == -1); |
c7c14b96 | 387 | |
735f54b4 MK |
388 | #ifdef PT_GET_PROCESS_STATE |
389 | if (WIFSTOPPED (status)) | |
390 | { | |
391 | ptrace_state_t pe; | |
392 | pid_t fpid; | |
393 | ||
394 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
395 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
396 | perror_with_name (("ptrace")); | |
397 | ||
398 | switch (pe.pe_report_event) | |
399 | { | |
400 | case PTRACE_FORK: | |
401 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
402 | ourstatus->value.related_pid = pe.pe_other_pid; | |
403 | ||
404 | /* Make sure the other end of the fork is stopped too. */ | |
405 | fpid = waitpid (pe.pe_other_pid, &status, 0); | |
406 | if (fpid == -1) | |
407 | perror_with_name (("waitpid")); | |
408 | ||
409 | if (ptrace (PT_GET_PROCESS_STATE, fpid, | |
410 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
411 | perror_with_name (("ptrace")); | |
412 | ||
413 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
414 | gdb_assert (pe.pe_other_pid == pid); | |
415 | if (fpid == ptid_get_pid (inferior_ptid)) | |
416 | { | |
417 | ourstatus->value.related_pid = pe.pe_other_pid; | |
418 | return pid_to_ptid (fpid); | |
419 | } | |
420 | ||
421 | return pid_to_ptid (pid); | |
422 | } | |
423 | } | |
424 | #endif | |
425 | ||
c7c14b96 MK |
426 | store_waitstatus (ourstatus, status); |
427 | return pid_to_ptid (pid); | |
5bf970f9 AC |
428 | } |
429 | ||
4b8a1a28 MK |
430 | /* Attempt a transfer all LEN bytes starting at OFFSET between the |
431 | inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer. | |
432 | Return the number of bytes actually transferred. */ | |
5bf970f9 AC |
433 | |
434 | static LONGEST | |
435 | inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, | |
961cb7b5 MK |
436 | const char *annex, gdb_byte *readbuf, |
437 | const gdb_byte *writebuf, | |
438 | ULONGEST offset, LONGEST len) | |
5bf970f9 | 439 | { |
4b8a1a28 MK |
440 | pid_t pid = ptid_get_pid (inferior_ptid); |
441 | ||
5bf970f9 AC |
442 | switch (object) |
443 | { | |
444 | case TARGET_OBJECT_MEMORY: | |
f929a579 AC |
445 | #ifdef PT_IO |
446 | /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO | |
447 | request that promises to be much more efficient in reading | |
448 | and writing data in the traced process's address space. */ | |
449 | { | |
450 | struct ptrace_io_desc piod; | |
4b8a1a28 | 451 | |
f929a579 | 452 | /* NOTE: We assume that there are no distinct address spaces |
b457b3dd MK |
453 | for instruction and data. However, on OpenBSD 3.9 and |
454 | later, PIOD_WRITE_D doesn't allow changing memory that's | |
455 | mapped read-only. Since most code segments will be | |
456 | read-only, using PIOD_WRITE_D will prevent us from | |
457 | inserting breakpoints, so we use PIOD_WRITE_I instead. */ | |
458 | piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D; | |
f929a579 AC |
459 | piod.piod_addr = writebuf ? (void *) writebuf : readbuf; |
460 | piod.piod_offs = (void *) (long) offset; | |
461 | piod.piod_len = len; | |
462 | ||
463 | errno = 0; | |
4b8a1a28 | 464 | if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0) |
f929a579 AC |
465 | /* Return the actual number of bytes read or written. */ |
466 | return piod.piod_len; | |
467 | /* If the PT_IO request is somehow not supported, fallback on | |
468 | using PT_WRITE_D/PT_READ_D. Otherwise we will return zero | |
469 | to indicate failure. */ | |
470 | if (errno != EINVAL) | |
471 | return 0; | |
472 | } | |
473 | #endif | |
474 | { | |
475 | union | |
476 | { | |
477 | PTRACE_TYPE_RET word; | |
4b8a1a28 | 478 | gdb_byte byte[sizeof (PTRACE_TYPE_RET)]; |
f929a579 AC |
479 | } buffer; |
480 | ULONGEST rounded_offset; | |
481 | LONGEST partial_len; | |
4b8a1a28 | 482 | |
cb85a953 AC |
483 | /* Round the start offset down to the next long word |
484 | boundary. */ | |
f929a579 | 485 | rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); |
4b8a1a28 | 486 | |
cb85a953 AC |
487 | /* Since ptrace will transfer a single word starting at that |
488 | rounded_offset the partial_len needs to be adjusted down to | |
489 | that (remember this function only does a single transfer). | |
490 | Should the required length be even less, adjust it down | |
491 | again. */ | |
492 | partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset; | |
493 | if (partial_len > len) | |
f929a579 | 494 | partial_len = len; |
4b8a1a28 | 495 | |
f929a579 AC |
496 | if (writebuf) |
497 | { | |
cb85a953 AC |
498 | /* If OFFSET:PARTIAL_LEN is smaller than |
499 | ROUNDED_OFFSET:WORDSIZE then a read/modify write will | |
500 | be needed. Read in the entire word. */ | |
f929a579 | 501 | if (rounded_offset < offset |
cb85a953 AC |
502 | || (offset + partial_len |
503 | < rounded_offset + sizeof (PTRACE_TYPE_RET))) | |
f929a579 | 504 | /* Need part of initial word -- fetch it. */ |
4b8a1a28 | 505 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
506 | (PTRACE_TYPE_ARG3)(uintptr_t) |
507 | rounded_offset, 0); | |
4b8a1a28 | 508 | |
f929a579 AC |
509 | /* Copy data to be written over corresponding part of |
510 | buffer. */ | |
f6ffd89b MK |
511 | memcpy (buffer.byte + (offset - rounded_offset), |
512 | writebuf, partial_len); | |
4b8a1a28 | 513 | |
f929a579 | 514 | errno = 0; |
4b8a1a28 | 515 | ptrace (PT_WRITE_D, pid, |
f7dd0ed7 UW |
516 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
517 | buffer.word); | |
f929a579 AC |
518 | if (errno) |
519 | { | |
520 | /* Using the appropriate one (I or D) is necessary for | |
521 | Gould NP1, at least. */ | |
522 | errno = 0; | |
4b8a1a28 | 523 | ptrace (PT_WRITE_I, pid, |
f7dd0ed7 UW |
524 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
525 | buffer.word); | |
f929a579 AC |
526 | if (errno) |
527 | return 0; | |
528 | } | |
529 | } | |
4b8a1a28 | 530 | |
f929a579 AC |
531 | if (readbuf) |
532 | { | |
533 | errno = 0; | |
4b8a1a28 | 534 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
535 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
536 | 0); | |
f929a579 AC |
537 | if (errno) |
538 | return 0; | |
539 | /* Copy appropriate bytes out of the buffer. */ | |
540 | memcpy (readbuf, buffer.byte + (offset - rounded_offset), | |
541 | partial_len); | |
542 | } | |
4b8a1a28 | 543 | |
f929a579 AC |
544 | return partial_len; |
545 | } | |
5bf970f9 AC |
546 | |
547 | case TARGET_OBJECT_UNWIND_TABLE: | |
548 | return -1; | |
549 | ||
550 | case TARGET_OBJECT_AUXV: | |
551 | return -1; | |
552 | ||
553 | case TARGET_OBJECT_WCOOKIE: | |
554 | return -1; | |
555 | ||
556 | default: | |
557 | return -1; | |
558 | } | |
559 | } | |
560 | ||
4b8a1a28 | 561 | /* Return non-zero if the thread specified by PTID is alive. */ |
c7c14b96 MK |
562 | |
563 | static int | |
564 | inf_ptrace_thread_alive (ptid_t ptid) | |
565 | { | |
4b8a1a28 MK |
566 | /* ??? Is kill the right way to do this? */ |
567 | return (kill (ptid_get_pid (ptid), 0) != -1); | |
c7c14b96 MK |
568 | } |
569 | ||
570 | /* Print status information about what we're accessing. */ | |
571 | ||
572 | static void | |
573 | inf_ptrace_files_info (struct target_ops *ignore) | |
574 | { | |
4b8a1a28 MK |
575 | printf_filtered (_("\tUsing the running image of %s %s.\n"), |
576 | attach_flag ? "attached" : "child", | |
577 | target_pid_to_str (inferior_ptid)); | |
5bf970f9 AC |
578 | } |
579 | ||
8785ced0 MK |
580 | /* Create a prototype ptrace target. The client can override it with |
581 | local methods. */ | |
582 | ||
5bf970f9 AC |
583 | struct target_ops * |
584 | inf_ptrace_target (void) | |
585 | { | |
586 | struct target_ops *t = inf_child_target (); | |
8785ced0 | 587 | |
5bf970f9 | 588 | t->to_attach = inf_ptrace_attach; |
5bf970f9 AC |
589 | t->to_detach = inf_ptrace_detach; |
590 | t->to_resume = inf_ptrace_resume; | |
591 | t->to_wait = inf_ptrace_wait; | |
5bf970f9 | 592 | t->to_files_info = inf_ptrace_files_info; |
4b8a1a28 | 593 | t->to_kill = inf_ptrace_kill; |
5bf970f9 | 594 | t->to_create_inferior = inf_ptrace_create_inferior; |
735f54b4 MK |
595 | #ifdef PT_GET_PROCESS_STATE |
596 | t->to_follow_fork = inf_ptrace_follow_fork; | |
e4ef629d MK |
597 | t->to_post_startup_inferior = inf_ptrace_post_startup_inferior; |
598 | t->to_post_attach = inf_ptrace_post_attach; | |
735f54b4 | 599 | #endif |
5bf970f9 | 600 | t->to_mourn_inferior = inf_ptrace_mourn_inferior; |
5bf970f9 | 601 | t->to_thread_alive = inf_ptrace_thread_alive; |
4b8a1a28 | 602 | t->to_pid_to_str = normal_pid_to_str; |
5bf970f9 | 603 | t->to_stop = inf_ptrace_stop; |
c7c14b96 | 604 | t->to_xfer_partial = inf_ptrace_xfer_partial; |
8785ced0 | 605 | |
c7c14b96 | 606 | ptrace_ops_hack = t; |
8785ced0 MK |
607 | return t; |
608 | } | |
609 | \f | |
610 | ||
4b8a1a28 | 611 | /* Pointer to a function that returns the offset within the user area |
8785ced0 | 612 | where a particular register is stored. */ |
7714d83a | 613 | static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int); |
8785ced0 MK |
614 | |
615 | /* Fetch register REGNUM from the inferior. */ | |
616 | ||
617 | static void | |
56be3814 | 618 | inf_ptrace_fetch_register (struct regcache *regcache, int regnum) |
8785ced0 MK |
619 | { |
620 | CORE_ADDR addr; | |
621 | size_t size; | |
622 | PTRACE_TYPE_RET *buf; | |
623 | int pid, i; | |
624 | ||
7714d83a UW |
625 | /* This isn't really an address, but ptrace thinks of it as one. */ |
626 | addr = inf_ptrace_register_u_offset (current_gdbarch, regnum, 0); | |
8d4c1ba3 UW |
627 | if (addr == (CORE_ADDR)-1 |
628 | || gdbarch_cannot_fetch_register (current_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 | ||
8785ced0 | 640 | size = register_size (current_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."), |
c9f4d572 UW |
651 | gdbarch_register_name (current_gdbarch, regnum), |
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) | |
f57d151a | 666 | for (regnum = 0; regnum < gdbarch_num_regs (current_gdbarch); regnum++) |
56be3814 | 667 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 | 668 | else |
56be3814 | 669 | inf_ptrace_fetch_register (regcache, regnum); |
8785ced0 MK |
670 | } |
671 | ||
672 | /* Store register REGNUM into the inferior. */ | |
673 | ||
674 | static void | |
56be3814 | 675 | inf_ptrace_store_register (const struct regcache *regcache, int regnum) |
8785ced0 MK |
676 | { |
677 | CORE_ADDR addr; | |
678 | size_t size; | |
679 | PTRACE_TYPE_RET *buf; | |
680 | int pid, i; | |
681 | ||
7714d83a UW |
682 | /* This isn't really an address, but ptrace thinks of it as one. */ |
683 | addr = inf_ptrace_register_u_offset (current_gdbarch, regnum, 1); | |
8d4c1ba3 UW |
684 | if (addr == (CORE_ADDR)-1 |
685 | || gdbarch_cannot_store_register (current_gdbarch, regnum)) | |
10d6c8cd DJ |
686 | return; |
687 | ||
8785ced0 | 688 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 689 | separate processes. */ |
8785ced0 MK |
690 | pid = ptid_get_lwp (inferior_ptid); |
691 | if (pid == 0) | |
692 | pid = ptid_get_pid (inferior_ptid); | |
693 | ||
8785ced0 | 694 | size = register_size (current_gdbarch, regnum); |
8785ced0 MK |
695 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
696 | buf = alloca (size); | |
697 | ||
10d6c8cd | 698 | /* Write the register contents into the inferior a chunk at a time. */ |
56be3814 | 699 | regcache_raw_collect (regcache, regnum, buf); |
8785ced0 MK |
700 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
701 | { | |
702 | errno = 0; | |
f7dd0ed7 | 703 | ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]); |
8785ced0 | 704 | if (errno != 0) |
4b8a1a28 | 705 | error (_("Couldn't write register %s (#%d): %s."), |
c9f4d572 UW |
706 | gdbarch_register_name (current_gdbarch, regnum), |
707 | regnum, safe_strerror (errno)); | |
8785ced0 MK |
708 | |
709 | addr += sizeof (PTRACE_TYPE_RET); | |
710 | } | |
711 | } | |
712 | ||
713 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do | |
714 | this for all registers. */ | |
715 | ||
716 | void | |
56be3814 | 717 | inf_ptrace_store_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
718 | { |
719 | if (regnum == -1) | |
f57d151a | 720 | for (regnum = 0; regnum < gdbarch_num_regs (current_gdbarch); regnum++) |
56be3814 | 721 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 | 722 | else |
56be3814 | 723 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 MK |
724 | } |
725 | ||
726 | /* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be | |
727 | a function returning the offset within the user area where a | |
728 | particular register is stored. */ | |
729 | ||
730 | struct target_ops * | |
7714d83a UW |
731 | inf_ptrace_trad_target (CORE_ADDR (*register_u_offset) |
732 | (struct gdbarch *, int, int)) | |
8785ced0 MK |
733 | { |
734 | struct target_ops *t = inf_ptrace_target(); | |
735 | ||
736 | gdb_assert (register_u_offset); | |
737 | inf_ptrace_register_u_offset = register_u_offset; | |
738 | t->to_fetch_registers = inf_ptrace_fetch_registers; | |
739 | t->to_store_registers = inf_ptrace_store_registers; | |
740 | ||
5bf970f9 AC |
741 | return t; |
742 | } |