Commit | Line | Data |
---|---|---|
2c4a536d | 1 | /* Low-level child interface to ptrace. |
5bf970f9 | 2 | |
197e01b6 | 3 | Copyright (C) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, |
281b533b | 4 | 1998, 1999, 2000, 2001, 2002, 2004, 2005, 2006 |
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 | |
8785ced0 | 31 | #include "gdb_assert.h" |
2c4a536d MK |
32 | #include "gdb_string.h" |
33 | #include "gdb_ptrace.h" | |
34a17005 | 34 | #include "gdb_wait.h" |
5bf970f9 AC |
35 | #include <signal.h> |
36 | ||
2c4a536d MK |
37 | #include "inf-child.h" |
38 | ||
39 | /* HACK: Save the ptrace ops returned by inf_ptrace_target. */ | |
5bf970f9 | 40 | static struct target_ops *ptrace_ops_hack; |
c7c14b96 MK |
41 | \f |
42 | ||
735f54b4 MK |
43 | #ifdef PT_GET_PROCESS_STATE |
44 | ||
45 | static int | |
ee057212 | 46 | inf_ptrace_follow_fork (struct target_ops *ops, int follow_child) |
735f54b4 MK |
47 | { |
48 | pid_t pid, fpid; | |
49 | ptrace_state_t pe; | |
50 | ||
51 | /* FIXME: kettenis/20050720: This stuff should really be passed as | |
52 | an argument by our caller. */ | |
53 | { | |
54 | ptid_t ptid; | |
55 | struct target_waitstatus status; | |
56 | ||
57 | get_last_target_status (&ptid, &status); | |
58 | gdb_assert (status.kind == TARGET_WAITKIND_FORKED); | |
59 | ||
60 | pid = ptid_get_pid (ptid); | |
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 | { | |
72 | inferior_ptid = pid_to_ptid (fpid); | |
73 | detach_breakpoints (pid); | |
74 | ||
75 | /* Reset breakpoints in the child as appropriate. */ | |
76 | follow_inferior_reset_breakpoints (); | |
77 | ||
78 | if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
79 | perror_with_name (("ptrace")); | |
80 | } | |
81 | else | |
82 | { | |
83 | inferior_ptid = pid_to_ptid (pid); | |
84 | detach_breakpoints (fpid); | |
85 | ||
86 | if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) == -1) | |
87 | perror_with_name (("ptrace")); | |
88 | } | |
89 | ||
90 | return 0; | |
91 | } | |
92 | ||
93 | #endif /* PT_GET_PROCESS_STATE */ | |
94 | \f | |
95 | ||
4b8a1a28 | 96 | /* Prepare to be traced. */ |
5bf970f9 AC |
97 | |
98 | static void | |
c7c14b96 | 99 | inf_ptrace_me (void) |
5bf970f9 | 100 | { |
c7c14b96 | 101 | /* "Trace me, Dr. Memory!" */ |
4b8a1a28 | 102 | ptrace (PT_TRACE_ME, 0, (PTRACE_TYPE_ARG3)0, 0); |
5bf970f9 AC |
103 | } |
104 | ||
4b8a1a28 | 105 | /* Start tracing PID. */ |
5bf970f9 AC |
106 | |
107 | static void | |
c7c14b96 | 108 | inf_ptrace_him (int pid) |
5bf970f9 | 109 | { |
c7c14b96 | 110 | push_target (ptrace_ops_hack); |
5bf970f9 | 111 | |
c7c14b96 MK |
112 | /* On some targets, there must be some explicit synchronization |
113 | between the parent and child processes after the debugger | |
114 | forks, and before the child execs the debuggee program. This | |
115 | call basically gives permission for the child to exec. */ | |
5bf970f9 | 116 | |
c7c14b96 | 117 | target_acknowledge_created_inferior (pid); |
5bf970f9 | 118 | |
c7c14b96 MK |
119 | /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will |
120 | be 1 or 2 depending on whether we're starting without or with a | |
121 | shell. */ | |
122 | startup_inferior (START_INFERIOR_TRAPS_EXPECTED); | |
123 | ||
124 | /* On some targets, there must be some explicit actions taken after | |
125 | the inferior has been started up. */ | |
126 | target_post_startup_inferior (pid_to_ptid (pid)); | |
5bf970f9 AC |
127 | } |
128 | ||
4b8a1a28 MK |
129 | /* Start a new inferior Unix child process. EXEC_FILE is the file to |
130 | run, ALLARGS is a string containing the arguments to the program. | |
131 | ENV is the environment vector to pass. If FROM_TTY is non-zero, be | |
132 | chatty about it. */ | |
5bf970f9 | 133 | |
c7c14b96 MK |
134 | static void |
135 | inf_ptrace_create_inferior (char *exec_file, char *allargs, char **env, | |
136 | int from_tty) | |
5bf970f9 | 137 | { |
c7c14b96 MK |
138 | fork_inferior (exec_file, allargs, env, inf_ptrace_me, inf_ptrace_him, |
139 | NULL, NULL); | |
5bf970f9 AC |
140 | } |
141 | ||
e4ef629d MK |
142 | #ifdef PT_GET_PROCESS_STATE |
143 | ||
144 | static void | |
145 | inf_ptrace_post_startup_inferior (ptid_t pid) | |
146 | { | |
147 | ptrace_event_t pe; | |
148 | ||
149 | /* Set the initial event mask. */ | |
150 | memset (&pe, 0, sizeof pe); | |
151 | pe.pe_set_event |= PTRACE_FORK; | |
152 | if (ptrace (PT_SET_EVENT_MASK, ptid_get_pid (pid), | |
153 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
154 | perror_with_name (("ptrace")); | |
155 | } | |
156 | ||
157 | #endif | |
158 | ||
4b8a1a28 MK |
159 | /* Clean up a rotting corpse of an inferior after it died. */ |
160 | ||
c7c14b96 MK |
161 | static void |
162 | inf_ptrace_mourn_inferior (void) | |
5bf970f9 | 163 | { |
4b8a1a28 MK |
164 | int status; |
165 | ||
166 | /* Wait just one more time to collect the inferior's exit status. | |
f010475d | 167 | Do not check whether this succeeds though, since we may be |
4b8a1a28 | 168 | dealing with a process that we attached to. Such a process will |
3d450bdd | 169 | only report its exit status to its original parent. */ |
4b8a1a28 MK |
170 | waitpid (ptid_get_pid (inferior_ptid), &status, 0); |
171 | ||
c7c14b96 MK |
172 | unpush_target (ptrace_ops_hack); |
173 | generic_mourn_inferior (); | |
5bf970f9 AC |
174 | } |
175 | ||
4b8a1a28 MK |
176 | /* Attach to the process specified by ARGS. If FROM_TTY is non-zero, |
177 | be chatty about it. */ | |
5bf970f9 AC |
178 | |
179 | static void | |
180 | inf_ptrace_attach (char *args, int from_tty) | |
181 | { | |
182 | char *exec_file; | |
4b8a1a28 | 183 | pid_t pid; |
5bf970f9 AC |
184 | char *dummy; |
185 | ||
186 | if (!args) | |
e2e0b3e5 | 187 | error_no_arg (_("process-id to attach")); |
5bf970f9 AC |
188 | |
189 | dummy = args; | |
190 | pid = strtol (args, &dummy, 0); | |
f6ffd89b | 191 | /* Some targets don't set errno on errors, grrr! */ |
6e1e94ea | 192 | if (pid == 0 && args == dummy) |
8a3fe4f8 | 193 | error (_("Illegal process-id: %s."), args); |
5bf970f9 | 194 | |
f6ffd89b | 195 | if (pid == getpid ()) /* Trying to masturbate? */ |
8a3fe4f8 | 196 | error (_("I refuse to debug myself!")); |
5bf970f9 AC |
197 | |
198 | if (from_tty) | |
199 | { | |
4b8a1a28 | 200 | exec_file = get_exec_file (0); |
5bf970f9 AC |
201 | |
202 | if (exec_file) | |
a3f17187 | 203 | printf_unfiltered (_("Attaching to program: %s, %s\n"), exec_file, |
5bf970f9 AC |
204 | target_pid_to_str (pid_to_ptid (pid))); |
205 | else | |
a3f17187 | 206 | printf_unfiltered (_("Attaching to %s\n"), |
5bf970f9 AC |
207 | target_pid_to_str (pid_to_ptid (pid))); |
208 | ||
209 | gdb_flush (gdb_stdout); | |
210 | } | |
211 | ||
6e1e94ea MK |
212 | #ifdef PT_ATTACH |
213 | errno = 0; | |
4b8a1a28 | 214 | ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0); |
6e1e94ea | 215 | if (errno != 0) |
e2e0b3e5 | 216 | perror_with_name (("ptrace")); |
6e1e94ea MK |
217 | attach_flag = 1; |
218 | #else | |
8a3fe4f8 | 219 | error (_("This system does not support attaching to a process")); |
6e1e94ea | 220 | #endif |
5bf970f9 AC |
221 | |
222 | inferior_ptid = pid_to_ptid (pid); | |
223 | push_target (ptrace_ops_hack); | |
224 | } | |
225 | ||
e4ef629d MK |
226 | #ifdef PT_GET_PROCESS_STATE |
227 | ||
228 | void | |
229 | inf_ptrace_post_attach (int pid) | |
230 | { | |
231 | ptrace_event_t pe; | |
232 | ||
233 | /* Set the initial event mask. */ | |
234 | memset (&pe, 0, sizeof pe); | |
235 | pe.pe_set_event |= PTRACE_FORK; | |
236 | if (ptrace (PT_SET_EVENT_MASK, pid, | |
237 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
238 | perror_with_name (("ptrace")); | |
239 | } | |
240 | ||
241 | #endif | |
242 | ||
4b8a1a28 | 243 | /* Detach from the inferior, optionally passing it the signal |
f010475d | 244 | specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ |
5bf970f9 AC |
245 | |
246 | static void | |
247 | inf_ptrace_detach (char *args, int from_tty) | |
248 | { | |
4b8a1a28 | 249 | pid_t pid = ptid_get_pid (inferior_ptid); |
6e1e94ea | 250 | int sig = 0; |
5bf970f9 AC |
251 | |
252 | if (from_tty) | |
253 | { | |
254 | char *exec_file = get_exec_file (0); | |
255 | if (exec_file == 0) | |
256 | exec_file = ""; | |
a3f17187 | 257 | printf_unfiltered (_("Detaching from program: %s, %s\n"), exec_file, |
5bf970f9 AC |
258 | target_pid_to_str (pid_to_ptid (pid))); |
259 | gdb_flush (gdb_stdout); | |
260 | } | |
261 | if (args) | |
6e1e94ea | 262 | sig = atoi (args); |
5bf970f9 | 263 | |
6e1e94ea | 264 | #ifdef PT_DETACH |
4b8a1a28 | 265 | /* We'd better not have left any breakpoints in the program or it'll |
f010475d | 266 | die when it hits one. Also note that this may only work if we |
4b8a1a28 MK |
267 | previously attached to the inferior. It *might* work if we |
268 | started the process ourselves. */ | |
6e1e94ea | 269 | errno = 0; |
4b8a1a28 | 270 | ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig); |
6e1e94ea | 271 | if (errno != 0) |
e2e0b3e5 | 272 | perror_with_name (("ptrace")); |
6e1e94ea MK |
273 | attach_flag = 0; |
274 | #else | |
8a3fe4f8 | 275 | error (_("This system does not support detaching from a process")); |
6e1e94ea | 276 | #endif |
5bf970f9 AC |
277 | |
278 | inferior_ptid = null_ptid; | |
279 | unpush_target (ptrace_ops_hack); | |
280 | } | |
281 | ||
4b8a1a28 MK |
282 | /* Kill the inferior. */ |
283 | ||
5bf970f9 | 284 | static void |
4b8a1a28 | 285 | inf_ptrace_kill (void) |
5bf970f9 | 286 | { |
4b8a1a28 | 287 | pid_t pid = ptid_get_pid (inferior_ptid); |
c7c14b96 | 288 | int status; |
c7c14b96 MK |
289 | |
290 | if (pid == 0) | |
291 | return; | |
292 | ||
4b8a1a28 MK |
293 | ptrace (PT_KILL, pid, (PTRACE_TYPE_ARG3)0, 0); |
294 | waitpid (pid, &status, 0); | |
295 | ||
c7c14b96 | 296 | target_mourn_inferior (); |
5bf970f9 AC |
297 | } |
298 | ||
4b8a1a28 | 299 | /* Stop the inferior. */ |
c7c14b96 | 300 | |
5bf970f9 | 301 | static void |
c7c14b96 | 302 | inf_ptrace_stop (void) |
5bf970f9 | 303 | { |
4b8a1a28 MK |
304 | /* Send a SIGINT to the process group. This acts just like the user |
305 | typed a ^C on the controlling terminal. Note that using a | |
306 | negative process number in kill() is a System V-ism. The proper | |
307 | BSD interface is killpg(). However, all modern BSDs support the | |
308 | System V interface too. */ | |
c7c14b96 | 309 | kill (-inferior_process_group, SIGINT); |
5bf970f9 AC |
310 | } |
311 | ||
4b8a1a28 MK |
312 | /* Resume execution of thread PTID, or all threads if PTID is -1. If |
313 | STEP is nonzero, single-step it. If SIGNAL is nonzero, give it | |
314 | that signal. */ | |
5bf970f9 AC |
315 | |
316 | static void | |
c7c14b96 | 317 | inf_ptrace_resume (ptid_t ptid, int step, enum target_signal signal) |
5bf970f9 | 318 | { |
4b8a1a28 | 319 | pid_t pid = ptid_get_pid (ptid); |
c7c14b96 | 320 | int request = PT_CONTINUE; |
c7c14b96 MK |
321 | |
322 | if (pid == -1) | |
4b8a1a28 MK |
323 | /* Resume all threads. Traditionally ptrace() only supports |
324 | single-threaded processes, so simply resume the inferior. */ | |
325 | pid = ptid_get_pid (inferior_ptid); | |
c7c14b96 MK |
326 | |
327 | if (step) | |
328 | { | |
329 | /* If this system does not support PT_STEP, a higher level | |
330 | function will have called single_step() to transmute the step | |
331 | request into a continue request (by setting breakpoints on | |
332 | all possible successor instructions), so we don't have to | |
333 | worry about that here. */ | |
334 | request = PT_STEP; | |
335 | } | |
336 | ||
337 | /* An address of (PTRACE_TYPE_ARG3)1 tells ptrace to continue from | |
338 | where it was. If GDB wanted it to start some other way, we have | |
4b8a1a28 | 339 | already written a new program counter value to the child. */ |
c7c14b96 | 340 | errno = 0; |
4b8a1a28 | 341 | ptrace (request, pid, (PTRACE_TYPE_ARG3)1, target_signal_to_host (signal)); |
c7c14b96 MK |
342 | if (errno != 0) |
343 | perror_with_name (("ptrace")); | |
5bf970f9 AC |
344 | } |
345 | ||
4b8a1a28 MK |
346 | /* Wait for the child specified by PTID to do something. Return the |
347 | process ID of the child, or MINUS_ONE_PTID in case of error; store | |
348 | the status in *OURSTATUS. */ | |
5bf970f9 | 349 | |
c7c14b96 MK |
350 | static ptid_t |
351 | inf_ptrace_wait (ptid_t ptid, struct target_waitstatus *ourstatus) | |
5bf970f9 | 352 | { |
4b8a1a28 MK |
353 | pid_t pid; |
354 | int status, save_errno; | |
5bf970f9 | 355 | |
c7c14b96 MK |
356 | do |
357 | { | |
4b8a1a28 | 358 | set_sigint_trap (); |
c7c14b96 | 359 | set_sigio_trap (); |
5bf970f9 | 360 | |
4b8a1a28 MK |
361 | do |
362 | { | |
363 | pid = waitpid (ptid_get_pid (ptid), &status, 0); | |
364 | save_errno = errno; | |
365 | } | |
366 | while (pid == -1 && errno == EINTR); | |
5bf970f9 | 367 | |
c7c14b96 | 368 | clear_sigio_trap (); |
c7c14b96 | 369 | clear_sigint_trap (); |
5bf970f9 | 370 | |
c7c14b96 MK |
371 | if (pid == -1) |
372 | { | |
c7c14b96 | 373 | fprintf_unfiltered (gdb_stderr, |
4b8a1a28 | 374 | _("Child process unexpectedly missing: %s.\n"), |
c7c14b96 MK |
375 | safe_strerror (save_errno)); |
376 | ||
377 | /* Claim it exited with unknown signal. */ | |
378 | ourstatus->kind = TARGET_WAITKIND_SIGNALLED; | |
379 | ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN; | |
4b8a1a28 | 380 | return minus_one_ptid; |
c7c14b96 MK |
381 | } |
382 | ||
4b8a1a28 MK |
383 | /* Ignore terminated detached child processes. */ |
384 | if (!WIFSTOPPED (status) && pid != ptid_get_pid (inferior_ptid)) | |
385 | pid = -1; | |
c7c14b96 | 386 | } |
4b8a1a28 | 387 | while (pid == -1); |
c7c14b96 | 388 | |
735f54b4 MK |
389 | #ifdef PT_GET_PROCESS_STATE |
390 | if (WIFSTOPPED (status)) | |
391 | { | |
392 | ptrace_state_t pe; | |
393 | pid_t fpid; | |
394 | ||
395 | if (ptrace (PT_GET_PROCESS_STATE, pid, | |
396 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
397 | perror_with_name (("ptrace")); | |
398 | ||
399 | switch (pe.pe_report_event) | |
400 | { | |
401 | case PTRACE_FORK: | |
402 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
403 | ourstatus->value.related_pid = pe.pe_other_pid; | |
404 | ||
405 | /* Make sure the other end of the fork is stopped too. */ | |
406 | fpid = waitpid (pe.pe_other_pid, &status, 0); | |
407 | if (fpid == -1) | |
408 | perror_with_name (("waitpid")); | |
409 | ||
410 | if (ptrace (PT_GET_PROCESS_STATE, fpid, | |
411 | (PTRACE_TYPE_ARG3)&pe, sizeof pe) == -1) | |
412 | perror_with_name (("ptrace")); | |
413 | ||
414 | gdb_assert (pe.pe_report_event == PTRACE_FORK); | |
415 | gdb_assert (pe.pe_other_pid == pid); | |
416 | if (fpid == ptid_get_pid (inferior_ptid)) | |
417 | { | |
418 | ourstatus->value.related_pid = pe.pe_other_pid; | |
419 | return pid_to_ptid (fpid); | |
420 | } | |
421 | ||
422 | return pid_to_ptid (pid); | |
423 | } | |
424 | } | |
425 | #endif | |
426 | ||
c7c14b96 MK |
427 | store_waitstatus (ourstatus, status); |
428 | return pid_to_ptid (pid); | |
5bf970f9 AC |
429 | } |
430 | ||
4b8a1a28 MK |
431 | /* Attempt a transfer all LEN bytes starting at OFFSET between the |
432 | inferior's OBJECT:ANNEX space and GDB's READBUF/WRITEBUF buffer. | |
433 | Return the number of bytes actually transferred. */ | |
5bf970f9 AC |
434 | |
435 | static LONGEST | |
436 | inf_ptrace_xfer_partial (struct target_ops *ops, enum target_object object, | |
961cb7b5 MK |
437 | const char *annex, gdb_byte *readbuf, |
438 | const gdb_byte *writebuf, | |
439 | ULONGEST offset, LONGEST len) | |
5bf970f9 | 440 | { |
4b8a1a28 MK |
441 | pid_t pid = ptid_get_pid (inferior_ptid); |
442 | ||
5bf970f9 AC |
443 | switch (object) |
444 | { | |
445 | case TARGET_OBJECT_MEMORY: | |
f929a579 AC |
446 | #ifdef PT_IO |
447 | /* OpenBSD 3.1, NetBSD 1.6 and FreeBSD 5.0 have a new PT_IO | |
448 | request that promises to be much more efficient in reading | |
449 | and writing data in the traced process's address space. */ | |
450 | { | |
451 | struct ptrace_io_desc piod; | |
4b8a1a28 | 452 | |
f929a579 | 453 | /* NOTE: We assume that there are no distinct address spaces |
b457b3dd MK |
454 | for instruction and data. However, on OpenBSD 3.9 and |
455 | later, PIOD_WRITE_D doesn't allow changing memory that's | |
456 | mapped read-only. Since most code segments will be | |
457 | read-only, using PIOD_WRITE_D will prevent us from | |
458 | inserting breakpoints, so we use PIOD_WRITE_I instead. */ | |
459 | piod.piod_op = writebuf ? PIOD_WRITE_I : PIOD_READ_D; | |
f929a579 AC |
460 | piod.piod_addr = writebuf ? (void *) writebuf : readbuf; |
461 | piod.piod_offs = (void *) (long) offset; | |
462 | piod.piod_len = len; | |
463 | ||
464 | errno = 0; | |
4b8a1a28 | 465 | if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0) |
f929a579 AC |
466 | /* Return the actual number of bytes read or written. */ |
467 | return piod.piod_len; | |
468 | /* If the PT_IO request is somehow not supported, fallback on | |
469 | using PT_WRITE_D/PT_READ_D. Otherwise we will return zero | |
470 | to indicate failure. */ | |
471 | if (errno != EINVAL) | |
472 | return 0; | |
473 | } | |
474 | #endif | |
475 | { | |
476 | union | |
477 | { | |
478 | PTRACE_TYPE_RET word; | |
4b8a1a28 | 479 | gdb_byte byte[sizeof (PTRACE_TYPE_RET)]; |
f929a579 AC |
480 | } buffer; |
481 | ULONGEST rounded_offset; | |
482 | LONGEST partial_len; | |
4b8a1a28 | 483 | |
cb85a953 AC |
484 | /* Round the start offset down to the next long word |
485 | boundary. */ | |
f929a579 | 486 | rounded_offset = offset & -(ULONGEST) sizeof (PTRACE_TYPE_RET); |
4b8a1a28 | 487 | |
cb85a953 AC |
488 | /* Since ptrace will transfer a single word starting at that |
489 | rounded_offset the partial_len needs to be adjusted down to | |
490 | that (remember this function only does a single transfer). | |
491 | Should the required length be even less, adjust it down | |
492 | again. */ | |
493 | partial_len = (rounded_offset + sizeof (PTRACE_TYPE_RET)) - offset; | |
494 | if (partial_len > len) | |
f929a579 | 495 | partial_len = len; |
4b8a1a28 | 496 | |
f929a579 AC |
497 | if (writebuf) |
498 | { | |
cb85a953 AC |
499 | /* If OFFSET:PARTIAL_LEN is smaller than |
500 | ROUNDED_OFFSET:WORDSIZE then a read/modify write will | |
501 | be needed. Read in the entire word. */ | |
f929a579 | 502 | if (rounded_offset < offset |
cb85a953 AC |
503 | || (offset + partial_len |
504 | < rounded_offset + sizeof (PTRACE_TYPE_RET))) | |
f929a579 | 505 | /* Need part of initial word -- fetch it. */ |
4b8a1a28 MK |
506 | buffer.word = ptrace (PT_READ_I, pid, |
507 | (PTRACE_TYPE_ARG3)(long)rounded_offset, 0); | |
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 MK |
515 | ptrace (PT_WRITE_D, pid, |
516 | (PTRACE_TYPE_ARG3)(long)rounded_offset, 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 MK |
522 | ptrace (PT_WRITE_I, pid, |
523 | (PTRACE_TYPE_ARG3)(long)rounded_offset, buffer.word); | |
f929a579 AC |
524 | if (errno) |
525 | return 0; | |
526 | } | |
527 | } | |
4b8a1a28 | 528 | |
f929a579 AC |
529 | if (readbuf) |
530 | { | |
531 | errno = 0; | |
4b8a1a28 MK |
532 | buffer.word = ptrace (PT_READ_I, pid, |
533 | (PTRACE_TYPE_ARG3)(long)rounded_offset, 0); | |
f929a579 AC |
534 | if (errno) |
535 | return 0; | |
536 | /* Copy appropriate bytes out of the buffer. */ | |
537 | memcpy (readbuf, buffer.byte + (offset - rounded_offset), | |
538 | partial_len); | |
539 | } | |
4b8a1a28 | 540 | |
f929a579 AC |
541 | return partial_len; |
542 | } | |
5bf970f9 AC |
543 | |
544 | case TARGET_OBJECT_UNWIND_TABLE: | |
545 | return -1; | |
546 | ||
547 | case TARGET_OBJECT_AUXV: | |
548 | return -1; | |
549 | ||
550 | case TARGET_OBJECT_WCOOKIE: | |
551 | return -1; | |
552 | ||
553 | default: | |
554 | return -1; | |
555 | } | |
556 | } | |
557 | ||
4b8a1a28 | 558 | /* Return non-zero if the thread specified by PTID is alive. */ |
c7c14b96 MK |
559 | |
560 | static int | |
561 | inf_ptrace_thread_alive (ptid_t ptid) | |
562 | { | |
4b8a1a28 MK |
563 | /* ??? Is kill the right way to do this? */ |
564 | return (kill (ptid_get_pid (ptid), 0) != -1); | |
c7c14b96 MK |
565 | } |
566 | ||
567 | /* Print status information about what we're accessing. */ | |
568 | ||
569 | static void | |
570 | inf_ptrace_files_info (struct target_ops *ignore) | |
571 | { | |
4b8a1a28 MK |
572 | printf_filtered (_("\tUsing the running image of %s %s.\n"), |
573 | attach_flag ? "attached" : "child", | |
574 | target_pid_to_str (inferior_ptid)); | |
5bf970f9 AC |
575 | } |
576 | ||
8785ced0 MK |
577 | /* Create a prototype ptrace target. The client can override it with |
578 | local methods. */ | |
579 | ||
5bf970f9 AC |
580 | struct target_ops * |
581 | inf_ptrace_target (void) | |
582 | { | |
583 | struct target_ops *t = inf_child_target (); | |
8785ced0 | 584 | |
5bf970f9 | 585 | t->to_attach = inf_ptrace_attach; |
5bf970f9 AC |
586 | t->to_detach = inf_ptrace_detach; |
587 | t->to_resume = inf_ptrace_resume; | |
588 | t->to_wait = inf_ptrace_wait; | |
5bf970f9 | 589 | t->to_files_info = inf_ptrace_files_info; |
4b8a1a28 | 590 | t->to_kill = inf_ptrace_kill; |
5bf970f9 | 591 | t->to_create_inferior = inf_ptrace_create_inferior; |
735f54b4 MK |
592 | #ifdef PT_GET_PROCESS_STATE |
593 | t->to_follow_fork = inf_ptrace_follow_fork; | |
e4ef629d MK |
594 | t->to_post_startup_inferior = inf_ptrace_post_startup_inferior; |
595 | t->to_post_attach = inf_ptrace_post_attach; | |
735f54b4 | 596 | #endif |
5bf970f9 | 597 | t->to_mourn_inferior = inf_ptrace_mourn_inferior; |
5bf970f9 | 598 | t->to_thread_alive = inf_ptrace_thread_alive; |
4b8a1a28 | 599 | t->to_pid_to_str = normal_pid_to_str; |
5bf970f9 | 600 | t->to_stop = inf_ptrace_stop; |
c7c14b96 | 601 | t->to_xfer_partial = inf_ptrace_xfer_partial; |
8785ced0 | 602 | |
c7c14b96 | 603 | ptrace_ops_hack = t; |
8785ced0 MK |
604 | return t; |
605 | } | |
606 | \f | |
607 | ||
4b8a1a28 | 608 | /* Pointer to a function that returns the offset within the user area |
8785ced0 MK |
609 | where a particular register is stored. */ |
610 | static CORE_ADDR (*inf_ptrace_register_u_offset)(int); | |
611 | ||
612 | /* Fetch register REGNUM from the inferior. */ | |
613 | ||
614 | static void | |
615 | inf_ptrace_fetch_register (int regnum) | |
616 | { | |
617 | CORE_ADDR addr; | |
618 | size_t size; | |
619 | PTRACE_TYPE_RET *buf; | |
620 | int pid, i; | |
621 | ||
10d6c8cd DJ |
622 | if (CANNOT_FETCH_REGISTER (regnum)) |
623 | { | |
624 | regcache_raw_supply (current_regcache, regnum, NULL); | |
625 | return; | |
626 | } | |
627 | ||
8785ced0 | 628 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 629 | separate processes. */ |
8785ced0 MK |
630 | pid = ptid_get_lwp (inferior_ptid); |
631 | if (pid == 0) | |
632 | pid = ptid_get_pid (inferior_ptid); | |
633 | ||
634 | /* This isn't really an address, but ptrace thinks of it as one. */ | |
635 | addr = inf_ptrace_register_u_offset (regnum); | |
636 | size = register_size (current_gdbarch, regnum); | |
637 | ||
638 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); | |
639 | buf = alloca (size); | |
640 | ||
10d6c8cd | 641 | /* Read the register contents from the inferior a chunk at a time. */ |
8785ced0 MK |
642 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) |
643 | { | |
644 | errno = 0; | |
4b8a1a28 | 645 | buf[i] = ptrace (PT_READ_U, pid, (PTRACE_TYPE_ARG3)addr, 0); |
8785ced0 | 646 | if (errno != 0) |
4b8a1a28 MK |
647 | error (_("Couldn't read register %s (#%d): %s."), |
648 | REGISTER_NAME (regnum), regnum, safe_strerror (errno)); | |
8785ced0 MK |
649 | |
650 | addr += sizeof (PTRACE_TYPE_RET); | |
651 | } | |
652 | regcache_raw_supply (current_regcache, regnum, buf); | |
653 | } | |
654 | ||
655 | /* Fetch register REGNUM from the inferior. If REGNUM is -1, do this | |
656 | for all registers. */ | |
657 | ||
658 | static void | |
659 | inf_ptrace_fetch_registers (int regnum) | |
660 | { | |
661 | if (regnum == -1) | |
662 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
663 | inf_ptrace_fetch_register (regnum); | |
664 | else | |
665 | inf_ptrace_fetch_register (regnum); | |
666 | } | |
667 | ||
668 | /* Store register REGNUM into the inferior. */ | |
669 | ||
670 | static void | |
671 | inf_ptrace_store_register (int regnum) | |
672 | { | |
673 | CORE_ADDR addr; | |
674 | size_t size; | |
675 | PTRACE_TYPE_RET *buf; | |
676 | int pid, i; | |
677 | ||
10d6c8cd DJ |
678 | if (CANNOT_STORE_REGISTER (regnum)) |
679 | return; | |
680 | ||
8785ced0 | 681 | /* Cater for systems like GNU/Linux, that implement threads as |
10d6c8cd | 682 | separate processes. */ |
8785ced0 MK |
683 | pid = ptid_get_lwp (inferior_ptid); |
684 | if (pid == 0) | |
685 | pid = ptid_get_pid (inferior_ptid); | |
686 | ||
687 | /* This isn't really an address, but ptrace thinks of it as one. */ | |
688 | addr = inf_ptrace_register_u_offset (regnum); | |
689 | size = register_size (current_gdbarch, regnum); | |
690 | ||
691 | gdb_assert ((size % sizeof (PTRACE_TYPE_RET)) == 0); | |
692 | buf = alloca (size); | |
693 | ||
10d6c8cd | 694 | /* Write the register contents into the inferior a chunk at a time. */ |
8785ced0 MK |
695 | regcache_raw_collect (current_regcache, regnum, buf); |
696 | for (i = 0; i < size / sizeof (PTRACE_TYPE_RET); i++) | |
697 | { | |
698 | errno = 0; | |
4b8a1a28 | 699 | ptrace (PT_WRITE_U, pid, (PTRACE_TYPE_ARG3)addr, buf[i]); |
8785ced0 | 700 | if (errno != 0) |
4b8a1a28 MK |
701 | error (_("Couldn't write register %s (#%d): %s."), |
702 | REGISTER_NAME (regnum), regnum, safe_strerror (errno)); | |
8785ced0 MK |
703 | |
704 | addr += sizeof (PTRACE_TYPE_RET); | |
705 | } | |
706 | } | |
707 | ||
708 | /* Store register REGNUM back into the inferior. If REGNUM is -1, do | |
709 | this for all registers. */ | |
710 | ||
711 | void | |
712 | inf_ptrace_store_registers (int regnum) | |
713 | { | |
714 | if (regnum == -1) | |
715 | for (regnum = 0; regnum < NUM_REGS; regnum++) | |
716 | inf_ptrace_store_register (regnum); | |
717 | else | |
718 | inf_ptrace_store_register (regnum); | |
719 | } | |
720 | ||
721 | /* Create a "traditional" ptrace target. REGISTER_U_OFFSET should be | |
722 | a function returning the offset within the user area where a | |
723 | particular register is stored. */ | |
724 | ||
725 | struct target_ops * | |
726 | inf_ptrace_trad_target (CORE_ADDR (*register_u_offset)(int)) | |
727 | { | |
728 | struct target_ops *t = inf_ptrace_target(); | |
729 | ||
730 | gdb_assert (register_u_offset); | |
731 | inf_ptrace_register_u_offset = register_u_offset; | |
732 | t->to_fetch_registers = inf_ptrace_fetch_registers; | |
733 | t->to_store_registers = inf_ptrace_store_registers; | |
734 | ||
5bf970f9 AC |
735 | return t; |
736 | } |