Commit | Line | Data |
---|---|---|
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 | |
11 | the Free Software Foundation; either version 2 of the License, or | |
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 | |
20 | along with this program; if not, write to the Free Software | |
197e01b6 EZ |
21 | Foundation, Inc., 51 Franklin Street, Fifth Floor, |
22 | Boston, MA 02110-1301, USA. */ | |
5bf970f9 AC |
23 | |
24 | #include "defs.h" | |
5bf970f9 | 25 | #include "command.h" |
2c4a536d MK |
26 | #include "inferior.h" |
27 | #include "inflow.h" | |
5bf970f9 | 28 | #include "gdbcore.h" |
8785ced0 | 29 | #include "regcache.h" |
5bf970f9 | 30 | |
f7dd0ed7 | 31 | #include "gdb_stdint.h" |
8785ced0 | 32 | #include "gdb_assert.h" |
2c4a536d MK |
33 | #include "gdb_string.h" |
34 | #include "gdb_ptrace.h" | |
34a17005 | 35 | #include "gdb_wait.h" |
5bf970f9 AC |
36 | #include <signal.h> |
37 | ||
2c4a536d MK |
38 | #include "inf-child.h" |
39 | ||
40 | /* HACK: Save the ptrace ops returned by inf_ptrace_target. */ | |
5bf970f9 | 41 | static struct target_ops *ptrace_ops_hack; |
c7c14b96 MK |
42 | \f |
43 | ||
735f54b4 MK |
44 | #ifdef PT_GET_PROCESS_STATE |
45 | ||
46 | static int | |
ee057212 | 47 | inf_ptrace_follow_fork (struct target_ops *ops, int follow_child) |
735f54b4 MK |
48 | { |
49 | pid_t pid, fpid; | |
50 | ptrace_state_t pe; | |
51 | ||
52 | /* FIXME: kettenis/20050720: This stuff should really be passed as | |
53 | an argument by our caller. */ | |
54 | { | |
55 | ptid_t ptid; | |
56 | struct target_waitstatus status; | |
57 | ||
58 | get_last_target_status (&ptid, &status); | |
59 | gdb_assert (status.kind == TARGET_WAITKIND_FORKED); | |
60 | ||
61 | pid = ptid_get_pid (ptid); | |
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 | { | |
73 | inferior_ptid = pid_to_ptid (fpid); | |
74 | detach_breakpoints (pid); | |
75 | ||
76 | /* Reset breakpoints in the child as appropriate. */ | |
77 | follow_inferior_reset_breakpoints (); | |
78 | ||
79 | if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
80 | perror_with_name (("ptrace")); | |
81 | } | |
82 | else | |
83 | { | |
84 | inferior_ptid = pid_to_ptid (pid); | |
85 | detach_breakpoints (fpid); | |
86 | ||
87 | if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
88 | perror_with_name (("ptrace")); | |
89 | } | |
90 | ||
91 | return 0; | |
92 | } | |
93 | ||
94 | #endif /* PT_GET_PROCESS_STATE */ | |
95 | \f | |
96 | ||
4b8a1a28 | 97 | /* Prepare to be traced. */ |
5bf970f9 AC |
98 | |
99 | static void | |
c7c14b96 | 100 | inf_ptrace_me (void) |
5bf970f9 | 101 | { |
c7c14b96 | 102 | /* "Trace me, Dr. Memory!" */ |
4b8a1a28 | 103 | ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0); |
5bf970f9 AC |
104 | } |
105 | ||
4b8a1a28 | 106 | /* Start tracing PID. */ |
5bf970f9 AC |
107 | |
108 | static void | |
c7c14b96 | 109 | inf_ptrace_him (int pid) |
5bf970f9 | 110 | { |
c7c14b96 | 111 | push_target (ptrace_ops_hack); |
5bf970f9 | 112 | |
c7c14b96 MK |
113 | /* On some targets, there must be some explicit synchronization |
114 | between the parent and child processes after the debugger | |
115 | forks, and before the child execs the debuggee program. This | |
116 | call basically gives permission for the child to exec. */ | |
5bf970f9 | 117 | |
c7c14b96 | 118 | target_acknowledge_created_inferior (pid); |
5bf970f9 | 119 | |
c7c14b96 MK |
120 | /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will |
121 | be 1 or 2 depending on whether we're starting without or with a | |
122 | shell. */ | |
123 | startup_inferior (START_INFERIOR_TRAPS_EXPECTED); | |
124 | ||
125 | /* On some targets, there must be some explicit actions taken after | |
126 | the inferior has been started up. */ | |
127 | target_post_startup_inferior (pid_to_ptid (pid)); | |
5bf970f9 AC |
128 | } |
129 | ||
4b8a1a28 MK |
130 | /* Start a new inferior Unix child process. EXEC_FILE is the file to |
131 | run, ALLARGS is a string containing the arguments to the program. | |
132 | ENV is the environment vector to pass. If FROM_TTY is non-zero, be | |
133 | chatty about it. */ | |
5bf970f9 | 134 | |
c7c14b96 MK |
135 | static void |
136 | inf_ptrace_create_inferior (char *exec_file, char *allargs, char **env, | |
137 | int from_tty) | |
5bf970f9 | 138 | { |
c7c14b96 MK |
139 | fork_inferior (exec_file, allargs, env, inf_ptrace_me, inf_ptrace_him, |
140 | NULL, NULL); | |
5bf970f9 AC |
141 | } |
142 | ||
e4ef629d MK |
143 | #ifdef PT_GET_PROCESS_STATE |
144 | ||
145 | static void | |
146 | inf_ptrace_post_startup_inferior (ptid_t pid) | |
147 | { | |
148 | ptrace_event_t pe; | |
149 | ||
150 | /* Set the initial event mask. */ | |
151 | memset (&pe, 0, sizeof pe); | |
152 | pe.pe_set_event |= PTRACE_FORK; | |
153 | if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid), | |
154 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
155 | perror_with_name (("ptrace")); | |
156 | } | |
157 | ||
158 | #endif | |
159 | ||
4b8a1a28 MK |
160 | /* Clean up a rotting corpse of an inferior after it died. */ |
161 | ||
c7c14b96 MK |
162 | static void |
163 | inf_ptrace_mourn_inferior (void) | |
5bf970f9 | 164 | { |
4b8a1a28 MK |
165 | int status; |
166 | ||
167 | /* Wait just one more time to collect the inferior's exit status. | |
f010475d | 168 | Do not check whether this succeeds though, since we may be |
4b8a1a28 | 169 | dealing with a process that we attached to. Such a process will |
3d450bdd | 170 | only report its exit status to its original parent. */ |
4b8a1a28 MK |
171 | waitpid (ptid_get_pid (inferior_ptid), &status, 0); |
172 | ||
c7c14b96 MK |
173 | unpush_target (ptrace_ops_hack); |
174 | generic_mourn_inferior (); | |
5bf970f9 AC |
175 | } |
176 | ||
4b8a1a28 MK |
177 | /* Attach to the process specified by ARGS. If FROM_TTY is non-zero, |
178 | be chatty about it. */ | |
5bf970f9 AC |
179 | |
180 | static void | |
181 | inf_ptrace_attach (char *args, int from_tty) | |
182 | { | |
183 | char *exec_file; | |
4b8a1a28 | 184 | pid_t pid; |
5bf970f9 AC |
185 | char *dummy; |
186 | ||
187 | if (!args) | |
e2e0b3e5 | 188 | error_no_arg (_("process-id to attach")); |
5bf970f9 AC |
189 | |
190 | dummy = args; | |
191 | pid = strtol (args, &dummy, 0); | |
f6ffd89b | 192 | /* Some targets don't set errno on errors, grrr! */ |
6e1e94ea | 193 | if (pid == 0 && args == dummy) |
8a3fe4f8 | 194 | error (_("Illegal process-id: %s."), args); |
5bf970f9 | 195 | |
f6ffd89b | 196 | if (pid == getpid ()) /* Trying to masturbate? */ |
8a3fe4f8 | 197 | error (_("I refuse to debug myself!")); |
5bf970f9 AC |
198 | |
199 | if (from_tty) | |
200 | { | |
4b8a1a28 | 201 | exec_file = get_exec_file (0); |
5bf970f9 AC |
202 | |
203 | if (exec_file) | |
a3f17187 | 204 | printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, |
5bf970f9 AC |
205 | target_pid_to_str (pid_to_ptid (pid))); |
206 | else | |
a3f17187 | 207 | printf_unfiltered (_("Attaching to %s\n"), |
5bf970f9 AC |
208 | target_pid_to_str (pid_to_ptid (pid))); |
209 | ||
210 | gdb_flush (gdb_stdout); | |
211 | } | |
212 | ||
6e1e94ea MK |
213 | #ifdef PT_ATTACH |
214 | errno = 0; | |
4b8a1a28 | 215 | ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0); |
6e1e94ea | 216 | if (errno != 0) |
e2e0b3e5 | 217 | perror_with_name (("ptrace")); |
6e1e94ea MK |
218 | attach_flag = 1; |
219 | #else | |
8a3fe4f8 | 220 | error (_("This system does not support attaching to a process")); |
6e1e94ea | 221 | #endif |
5bf970f9 AC |
222 | |
223 | inferior_ptid = pid_to_ptid (pid); | |
224 | push_target (ptrace_ops_hack); | |
225 | } | |
226 | ||
e4ef629d MK |
227 | #ifdef PT_GET_PROCESS_STATE |
228 | ||
229 | void | |
230 | inf_ptrace_post_attach (int pid) | |
231 | { | |
232 | ptrace_event_t pe; | |
233 | ||
234 | /* Set the initial event mask. */ | |
235 | memset (&pe, 0, sizeof pe); | |
236 | pe.pe_set_event |= PTRACE_FORK; | |
237 | if (ptrace (PT_SET_EVENT_MASK, pid, | |
238 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
239 | perror_with_name (("ptrace")); | |
240 | } | |
241 | ||
242 | #endif | |
243 | ||
4b8a1a28 | 244 | /* Detach from the inferior, optionally passing it the signal |
f010475d | 245 | specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ |
5bf970f9 AC |
246 | |
247 | static void | |
248 | inf_ptrace_detach (char *args, int from_tty) | |
249 | { | |
4b8a1a28 | 250 | pid_t pid = ptid_get_pid (inferior_ptid); |
6e1e94ea | 251 | int sig = 0; |
5bf970f9 AC |
252 | |
253 | if (from_tty) | |
254 | { | |
255 | char *exec_file = get_exec_file (0); | |
256 | if (exec_file == 0) | |
257 | exec_file = ""; | |
a3f17187 | 258 | printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, |
5bf970f9 AC |
259 | target_pid_to_str (pid_to_ptid (pid))); |
260 | gdb_flush (gdb_stdout); | |
261 | } | |
262 | if (args) | |
6e1e94ea | 263 | sig = atoi (args); |
5bf970f9 | 264 | |
6e1e94ea | 265 | #ifdef PT_DETACH |
4b8a1a28 | 266 | /* We'd better not have left any breakpoints in the program or it'll |
f010475d | 267 | die when it hits one. Also note that this may only work if we |
4b8a1a28 MK |
268 | previously attached to the inferior. It *might* work if we |
269 | started the process ourselves. */ | |
6e1e94ea | 270 | errno = 0; |
4b8a1a28 | 271 | ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig); |
6e1e94ea | 272 | if (errno != 0) |
e2e0b3e5 | 273 | perror_with_name (("ptrace")); |
6e1e94ea MK |
274 | attach_flag = 0; |
275 | #else | |
8a3fe4f8 | 276 | error (_("This system does not support detaching from a process")); |
6e1e94ea | 277 | #endif |
5bf970f9 AC |
278 | |
279 | inferior_ptid = null_ptid; | |
280 | unpush_target (ptrace_ops_hack); | |
281 | } | |
282 | ||
4b8a1a28 MK |
283 | /* Kill the inferior. */ |
284 | ||
5bf970f9 | 285 | static void |
4b8a1a28 | 286 | inf_ptrace_kill (void) |
5bf970f9 | 287 | { |
4b8a1a28 | 288 | pid_t pid = ptid_get_pid (inferior_ptid); |
c7c14b96 | 289 | int status; |
c7c14b96 MK |
290 | |
291 | if (pid == 0) | |
292 | return; | |
293 | ||
4b8a1a28 MK |
294 | ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0); |
295 | waitpid (pid, &status, 0); | |
296 | ||
c7c14b96 | 297 | target_mourn_inferior (); |
5bf970f9 AC |
298 | } |
299 | ||
4b8a1a28 | 300 | /* Stop the inferior. */ |
c7c14b96 | 301 | |
5bf970f9 | 302 | static void |
c7c14b96 | 303 | inf_ptrace_stop (void) |
5bf970f9 | 304 | { |
4b8a1a28 MK |
305 | /* Send a SIGINT to the process group. This acts just like the user |
306 | typed a ^C on the controlling terminal. Note that using a | |
307 | negative process number in kill() is a System V-ism. The proper | |
308 | BSD interface is killpg(). However, all modern BSDs support the | |
309 | System V interface too. */ | |
c7c14b96 | 310 | kill (-inferior_process_group, SIGINT); |
5bf970f9 AC |
311 | } |
312 | ||
4b8a1a28 MK |
313 | /* Resume execution of thread PTID, or all threads if PTID is -1. If |
314 | STEP is nonzero, single-step it. If SIGNAL is nonzero, give it | |
315 | that signal. */ | |
5bf970f9 AC |
316 | |
317 | static void | |
c7c14b96 | 318 | inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal) |
5bf970f9 | 319 | { |
4b8a1a28 | 320 | pid_t pid = ptid_get_pid (ptid); |
c7c14b96 | 321 | int request = PT_CONTINUE; |
c7c14b96 MK |
322 | |
323 | if (pid == -1) | |
4b8a1a28 MK |
324 | /* Resume all threads. Traditionally ptrace() only supports |
325 | single-threaded processes, so simply resume the inferior. */ | |
326 | pid = ptid_get_pid (inferior_ptid); | |
c7c14b96 MK |
327 | |
328 | if (step) | |
329 | { | |
330 | /* If this system does not support PT_STEP, a higher level | |
331 | function will have called single_step() to transmute the step | |
332 | request into a continue request (by setting breakpoints on | |
333 | all possible successor instructions), so we don't have to | |
334 | worry about that here. */ | |
335 | request = PT_STEP; | |
336 | } | |
337 | ||
338 | /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from | |
339 | where it was. If GDB wanted it to start some other way, we have | |
4b8a1a28 | 340 | already written a new program counter value to the child. */ |
c7c14b96 | 341 | errno = 0; |
4b8a1a28 | 342 | ptrace (request, pid, (PTRACE_TYPE_ARG3)1, target_signal_to_host (signal)); |
c7c14b96 MK |
343 | if (errno != 0) |
344 | perror_with_name (("ptrace")); | |
5bf970f9 AC |
345 | } |
346 | ||
4b8a1a28 MK |
347 | /* Wait for the child specified by PTID to do something. Return the |
348 | process ID of the child, or MINUS_ONE_PTID in case of error; store | |
349 | the status in *OURSTATUS. */ | |
5bf970f9 | 350 | |
c7c14b96 MK |
351 | static ptid_t |
352 | inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
5bf970f9 | 353 | { |
4b8a1a28 MK |
354 | pid_t pid; |
355 | int status, save_errno; | |
5bf970f9 | 356 | |
c7c14b96 MK |
357 | do |
358 | { | |
4b8a1a28 | 359 | set_sigint_trap (); |
c7c14b96 | 360 | set_sigio_trap (); |
5bf970f9 | 361 | |
4b8a1a28 MK |
362 | do |
363 | { | |
364 | pid = waitpid (ptid_get_pid (ptid), &status, 0); | |
365 | save_errno = errno; | |
366 | } | |
367 | while (pid == -1 && errno == EINTR); | |
5bf970f9 | 368 | |
c7c14b96 | 369 | clear_sigio_trap (); |
c7c14b96 | 370 | clear_sigint_trap (); |
5bf970f9 | 371 | |
c7c14b96 MK |
372 | if (pid == -1) |
373 | { | |
c7c14b96 | 374 | fprintf_unfiltered (gdb_stderr, |
4b8a1a28 | 375 | _("Child process unexpectedly missing: %s.\n"), |
c7c14b96 MK |
376 | safe_strerror (save_errno)); |
377 | ||
378 | /* Claim it exited with unknown signal. */ | |
379 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
380 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
4b8a1a28 | 381 | return minus_one_ptid; |
c7c14b96 MK |
382 | } |
383 | ||
4b8a1a28 MK |
384 | /* Ignore terminated detached child processes. */ |
385 | if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid)) | |
386 | pid = -1; | |
c7c14b96 | 387 | } |
4b8a1a28 | 388 | while (pid == -1); |
c7c14b96 | 389 | |
735f54b4 MK |
390 | #ifdef PT_GET_PROCESS_STATE |
391 | if (WIFSTOPPED (status)) | |
392 | { | |
393 | ptrace_state_t pe; | |
394 | pid_t fpid; | |
395 | ||
396 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
397 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
398 | perror_with_name (("ptrace")); | |
399 | ||
400 | switch (pe.pe_report_event) | |
401 | { | |
402 | case PTRACE_FORK: | |
403 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
404 | ourstatus->value.related_pid = pe.pe_other_pid; | |
405 | ||
406 | /* Make sure the other end of the fork is stopped too. */ | |
407 | fpid = waitpid (pe.pe_other_pid, &status, 0); | |
408 | if (fpid == -1) | |
409 | perror_with_name (("waitpid")); | |
410 | ||
411 | if (ptrace (PT_GET_PROCESS_STATE, fpid, | |
412 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
413 | perror_with_name (("ptrace")); | |
414 | ||
415 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
416 | gdb_assert (pe.pe_other_pid == pid); | |
417 | if (fpid == ptid_get_pid (inferior_ptid)) | |
418 | { | |
419 | ourstatus->value.related_pid = pe.pe_other_pid; | |
420 | return pid_to_ptid (fpid); | |
421 | } | |
422 | ||
423 | return pid_to_ptid (pid); | |
424 | } | |
425 | } | |
426 | #endif | |
427 | ||
c7c14b96 MK |
428 | store_waitstatus (ourstatus, status); |
429 | return pid_to_ptid (pid); | |
5bf970f9 AC |
430 | } |
431 | ||
4b8a1a28 MK |
432 | /* Attempt a transfer all LEN bytes starting at OFFSET between the |
433 | inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer. | |
434 | Return the number of bytes actually transferred. */ | |
5bf970f9 AC |
435 | |
436 | static LONGEST | |
437 | inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, | |
961cb7b5 MK |
438 | const char *annex, gdb_byte *readbuf, |
439 | const gdb_byte *writebuf, | |
440 | ULONGEST offset, LONGEST len) | |
5bf970f9 | 441 | { |
4b8a1a28 MK |
442 | pid_t pid = ptid_get_pid (inferior_ptid); |
443 | ||
5bf970f9 AC |
444 | switch (object) |
445 | { | |
446 | case TARGET_OBJECT_MEMORY: | |
f929a579 AC |
447 | #ifdef PT_IO |
448 | /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO | |
449 | request that promises to be much more efficient in reading | |
450 | and writing data in the traced process's address space. */ | |
451 | { | |
452 | struct ptrace_io_desc piod; | |
4b8a1a28 | 453 | |
f929a579 | 454 | /* NOTE: We assume that there are no distinct address spaces |
b457b3dd MK |
455 | for instruction and data. However, on OpenBSD 3.9 and |
456 | later, PIOD_WRITE_D doesn't allow changing memory that's | |
457 | mapped read-only. Since most code segments will be | |
458 | read-only, using PIOD_WRITE_D will prevent us from | |
459 | inserting breakpoints, so we use PIOD_WRITE_I instead. */ | |
460 | piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D; | |
f929a579 AC |
461 | piod.piod_addr = writebuf ? (void *) writebuf : readbuf; |
462 | piod.piod_offs = (void *) (long) offset; | |
463 | piod.piod_len = len; | |
464 | ||
465 | errno = 0; | |
4b8a1a28 | 466 | if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0) |
f929a579 AC |
467 | /* Return the actual number of bytes read or written. */ |
468 | return piod.piod_len; | |
469 | /* If the PT_IO request is somehow not supported, fallback on | |
470 | using PT_WRITE_D/PT_READ_D. Otherwise we will return zero | |
471 | to indicate failure. */ | |
472 | if (errno != EINVAL) | |
473 | return 0; | |
474 | } | |
475 | #endif | |
476 | { | |
477 | union | |
478 | { | |
479 | PTRACE_TYPE_RET word; | |
4b8a1a28 | 480 | gdb_byte byte[sizeof (PTRACE_TYPE_RET)]; |
f929a579 AC |
481 | } buffer; |
482 | ULONGEST rounded_offset; | |
483 | LONGEST partial_len; | |
4b8a1a28 | 484 | |
cb85a953 AC |
485 | /* Round the start offset down to the next long word |
486 | boundary. */ | |
f929a579 | 487 | rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); |
4b8a1a28 | 488 | |
cb85a953 AC |
489 | /* Since ptrace will transfer a single word starting at that |
490 | rounded_offset the partial_len needs to be adjusted down to | |
491 | that (remember this function only does a single transfer). | |
492 | Should the required length be even less, adjust it down | |
493 | again. */ | |
494 | partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset; | |
495 | if (partial_len > len) | |
f929a579 | 496 | partial_len = len; |
4b8a1a28 | 497 | |
f929a579 AC |
498 | if (writebuf) |
499 | { | |
cb85a953 AC |
500 | /* If OFFSET:PARTIAL_LEN is smaller than |
501 | ROUNDED_OFFSET:WORDSIZE then a read/modify write will | |
502 | be needed. Read in the entire word. */ | |
f929a579 | 503 | if (rounded_offset < offset |
cb85a953 AC |
504 | || (offset + partial_len |
505 | < rounded_offset + sizeof (PTRACE_TYPE_RET))) | |
f929a579 | 506 | /* Need part of initial word -- fetch it. */ |
4b8a1a28 | 507 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
508 | (PTRACE_TYPE_ARG3)(uintptr_t) |
509 | rounded_offset, 0); | |
4b8a1a28 | 510 | |
f929a579 AC |
511 | /* Copy data to be written over corresponding part of |
512 | buffer. */ | |
f6ffd89b MK |
513 | memcpy (buffer.byte + (offset - rounded_offset), |
514 | writebuf, partial_len); | |
4b8a1a28 | 515 | |
f929a579 | 516 | errno = 0; |
4b8a1a28 | 517 | ptrace (PT_WRITE_D, pid, |
f7dd0ed7 UW |
518 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
519 | buffer.word); | |
f929a579 AC |
520 | if (errno) |
521 | { | |
522 | /* Using the appropriate one (I or D) is necessary for | |
523 | Gould NP1, at least. */ | |
524 | errno = 0; | |
4b8a1a28 | 525 | ptrace (PT_WRITE_I, pid, |
f7dd0ed7 UW |
526 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
527 | buffer.word); | |
f929a579 AC |
528 | if (errno) |
529 | return 0; | |
530 | } | |
531 | } | |
4b8a1a28 | 532 | |
f929a579 AC |
533 | if (readbuf) |
534 | { | |
535 | errno = 0; | |
4b8a1a28 | 536 | buffer.word = ptrace (PT_READ_I, pid, |
f7dd0ed7 UW |
537 | (PTRACE_TYPE_ARG3)(uintptr_t)rounded_offset, |
538 | 0); | |
f929a579 AC |
539 | if (errno) |
540 | return 0; | |
541 | /* Copy appropriate bytes out of the buffer. */ | |
542 | memcpy (readbuf, buffer.byte + (offset - rounded_offset), | |
543 | partial_len); | |
544 | } | |
4b8a1a28 | 545 | |
f929a579 AC |
546 | return partial_len; |
547 | } | |
5bf970f9 AC |
548 | |
549 | case TARGET_OBJECT_UNWIND_TABLE: | |
550 | return -1; | |
551 | ||
552 | case TARGET_OBJECT_AUXV: | |
553 | return -1; | |
554 | ||
555 | case TARGET_OBJECT_WCOOKIE: | |
556 | return -1; | |
557 | ||
558 | default: | |
559 | return -1; | |
560 | } | |
561 | } | |
562 | ||
4b8a1a28 | 563 | /* Return non-zero if the thread specified by PTID is alive. */ |
c7c14b96 MK |
564 | |
565 | static int | |
566 | inf_ptrace_thread_alive (ptid_t ptid) | |
567 | { | |
4b8a1a28 MK |
568 | /* ??? Is kill the right way to do this? */ |
569 | return (kill (ptid_get_pid (ptid), 0) != -1); | |
c7c14b96 MK |
570 | } |
571 | ||
572 | /* Print status information about what we're accessing. */ | |
573 | ||
574 | static void | |
575 | inf_ptrace_files_info (struct target_ops *ignore) | |
576 | { | |
4b8a1a28 MK |
577 | printf_filtered (_("\tUsing the running image of %s %s.\n"), |
578 | attach_flag ? "attached" : "child", | |
579 | target_pid_to_str (inferior_ptid)); | |
5bf970f9 AC |
580 | } |
581 | ||
8785ced0 MK |
582 | /* Create a prototype ptrace target. The client can override it with |
583 | local methods. */ | |
584 | ||
5bf970f9 AC |
585 | struct target_ops * |
586 | inf_ptrace_target (void) | |
587 | { | |
588 | struct target_ops *t = inf_child_target (); | |
8785ced0 | 589 | |
5bf970f9 | 590 | t->to_attach = inf_ptrace_attach; |
5bf970f9 AC |
591 | t->to_detach = inf_ptrace_detach; |
592 | t->to_resume = inf_ptrace_resume; | |
593 | t->to_wait = inf_ptrace_wait; | |
5bf970f9 | 594 | t->to_files_info = inf_ptrace_files_info; |
4b8a1a28 | 595 | t->to_kill = inf_ptrace_kill; |
5bf970f9 | 596 | t->to_create_inferior = inf_ptrace_create_inferior; |
735f54b4 MK |
597 | #ifdef PT_GET_PROCESS_STATE |
598 | t->to_follow_fork = inf_ptrace_follow_fork; | |
e4ef629d MK |
599 | t->to_post_startup_inferior = inf_ptrace_post_startup_inferior; |
600 | t->to_post_attach = inf_ptrace_post_attach; | |
735f54b4 | 601 | #endif |
5bf970f9 | 602 | t->to_mourn_inferior = inf_ptrace_mourn_inferior; |
5bf970f9 | 603 | t->to_thread_alive = inf_ptrace_thread_alive; |
4b8a1a28 | 604 | t->to_pid_to_str = normal_pid_to_str; |
5bf970f9 | 605 | t->to_stop = inf_ptrace_stop; |
c7c14b96 | 606 | t->to_xfer_partial = inf_ptrace_xfer_partial; |
8785ced0 | 607 | |
c7c14b96 | 608 | ptrace_ops_hack = t; |
8785ced0 MK |
609 | return t; |
610 | } | |
611 | \f | |
612 | ||
4b8a1a28 | 613 | /* Pointer to a function that returns the offset within the user area |
8785ced0 | 614 | where a particular register is stored. */ |
7714d83a | 615 | static CORE_ADDR (*inf_ptrace_register_u_offset)(struct gdbarch *, int, int); |
8785ced0 MK |
616 | |
617 | /* Fetch register REGNUM from the inferior. */ | |
618 | ||
619 | static void | |
56be3814 | 620 | inf_ptrace_fetch_register (struct regcache *regcache, int regnum) |
8785ced0 MK |
621 | { |
622 | CORE_ADDR addr; | |
623 | size_t size; | |
624 | PTRACE_TYPE_RET *buf; | |
625 | int pid, i; | |
626 | ||
7714d83a UW |
627 | /* This isn't really an address, but ptrace thinks of it as one. */ |
628 | addr = inf_ptrace_register_u_offset (current_gdbarch, regnum, 0); | |
8d4c1ba3 UW |
629 | if (addr == (CORE_ADDR)-1 |
630 | || gdbarch_cannot_fetch_register (current_gdbarch, regnum)) | |
10d6c8cd | 631 | { |
56be3814 | 632 | regcache_raw_supply (regcache, regnum, NULL); |
10d6c8cd DJ |
633 | return; |
634 | } | |
635 | ||
8785ced0 | 636 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 637 | separate processes. */ |
8785ced0 MK |
638 | pid = ptid_get_lwp (inferior_ptid); |
639 | if (pid == 0) | |
640 | pid = ptid_get_pid (inferior_ptid); | |
641 | ||
8785ced0 | 642 | size = register_size (current_gdbarch, regnum); |
8785ced0 MK |
643 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
644 | buf = alloca (size); | |
645 | ||
10d6c8cd | 646 | /* Read the register contents from the inferior a chunk at a time. */ |
8785ced0 MK |
647 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
648 | { | |
649 | errno = 0; | |
f7dd0ed7 | 650 | buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, 0); |
8785ced0 | 651 | if (errno != 0) |
4b8a1a28 | 652 | error (_("Couldn't read register %s (#%d): %s."), |
c9f4d572 UW |
653 | gdbarch_register_name (current_gdbarch, regnum), |
654 | regnum, safe_strerror (errno)); | |
8785ced0 MK |
655 | |
656 | addr += sizeof (PTRACE_TYPE_RET); | |
657 | } | |
56be3814 | 658 | regcache_raw_supply (regcache, regnum, buf); |
8785ced0 MK |
659 | } |
660 | ||
661 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this | |
662 | for all registers. */ | |
663 | ||
664 | static void | |
56be3814 | 665 | inf_ptrace_fetch_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
666 | { |
667 | if (regnum == -1) | |
f57d151a | 668 | for (regnum = 0; regnum < gdbarch_num_regs (current_gdbarch); 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 MK |
678 | { |
679 | CORE_ADDR addr; | |
680 | size_t size; | |
681 | PTRACE_TYPE_RET *buf; | |
682 | int pid, i; | |
683 | ||
7714d83a UW |
684 | /* This isn't really an address, but ptrace thinks of it as one. */ |
685 | addr = inf_ptrace_register_u_offset (current_gdbarch, regnum, 1); | |
8d4c1ba3 UW |
686 | if (addr == (CORE_ADDR)-1 |
687 | || gdbarch_cannot_store_register (current_gdbarch, regnum)) | |
10d6c8cd DJ |
688 | return; |
689 | ||
8785ced0 | 690 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 691 | separate processes. */ |
8785ced0 MK |
692 | pid = ptid_get_lwp (inferior_ptid); |
693 | if (pid == 0) | |
694 | pid = ptid_get_pid (inferior_ptid); | |
695 | ||
8785ced0 | 696 | size = register_size (current_gdbarch, regnum); |
8785ced0 MK |
697 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); |
698 | buf = alloca (size); | |
699 | ||
10d6c8cd | 700 | /* Write the register contents into the inferior a chunk at a time. */ |
56be3814 | 701 | regcache_raw_collect (regcache, regnum, buf); |
8785ced0 MK |
702 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
703 | { | |
704 | errno = 0; | |
f7dd0ed7 | 705 | ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)(uintptr_t)addr, buf[i]); |
8785ced0 | 706 | if (errno != 0) |
4b8a1a28 | 707 | error (_("Couldn't write register %s (#%d): %s."), |
c9f4d572 UW |
708 | gdbarch_register_name (current_gdbarch, regnum), |
709 | regnum, safe_strerror (errno)); | |
8785ced0 MK |
710 | |
711 | addr += sizeof (PTRACE_TYPE_RET); | |
712 | } | |
713 | } | |
714 | ||
715 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do | |
716 | this for all registers. */ | |
717 | ||
718 | void | |
56be3814 | 719 | inf_ptrace_store_registers (struct regcache *regcache, int regnum) |
8785ced0 MK |
720 | { |
721 | if (regnum == -1) | |
f57d151a | 722 | for (regnum = 0; regnum < gdbarch_num_regs (current_gdbarch); regnum++) |
56be3814 | 723 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 | 724 | else |
56be3814 | 725 | inf_ptrace_store_register (regcache, regnum); |
8785ced0 MK |
726 | } |
727 | ||
728 | /* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be | |
729 | a function returning the offset within the user area where a | |
730 | particular register is stored. */ | |
731 | ||
732 | struct target_ops * | |
7714d83a UW |
733 | inf_ptrace_trad_target (CORE_ADDR (*register_u_offset) |
734 | (struct gdbarch *, int, int)) | |
8785ced0 MK |
735 | { |
736 | struct target_ops *t = inf_ptrace_target(); | |
737 | ||
738 | gdb_assert (register_u_offset); | |
739 | inf_ptrace_register_u_offset = register_u_offset; | |
740 | t->to_fetch_registers = inf_ptrace_fetch_registers; | |
741 | t->to_store_registers = inf_ptrace_store_registers; | |
742 | ||
5bf970f9 AC |
743 | return t; |
744 | } |