1 /* Native-dependent code for FreeBSD.
3 Copyright (C) 2002-2018 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "byte-vector.h"
27 #include "gdbthread.h"
29 #include "inf-ptrace.h"
30 #include <sys/types.h>
31 #include <sys/procfs.h>
32 #include <sys/ptrace.h>
33 #include <sys/signal.h>
34 #include <sys/sysctl.h>
36 #if defined(HAVE_KINFO_GETFILE) || defined(HAVE_KINFO_GETVMMAP)
39 #if !defined(HAVE_KINFO_GETVMMAP)
40 #include "filestuff.h"
45 #include "fbsd-tdep.h"
49 /* Return the name of a file that can be opened to get the symbols for
50 the child process identified by PID. */
53 fbsd_nat_target::pid_to_exec_file (int pid)
56 static char buf[PATH_MAX];
59 #ifdef KERN_PROC_PATHNAME
65 mib[2] = KERN_PROC_PATHNAME;
68 if (sysctl (mib, 4, buf, &buflen, NULL, 0) == 0)
69 /* The kern.proc.pathname.<pid> sysctl returns a length of zero
70 for processes without an associated executable such as kernel
72 return buflen == 0 ? NULL : buf;
75 xsnprintf (name, PATH_MAX, "/proc/%d/exe", pid);
76 len = readlink (name, buf, PATH_MAX - 1);
86 #ifdef HAVE_KINFO_GETVMMAP
87 /* Iterate over all the memory regions in the current inferior,
88 calling FUNC for each memory region. OBFD is passed as the last
92 fbsd_nat_target::find_memory_regions (find_memory_region_ftype func,
95 pid_t pid = inferior_ptid.pid ();
96 struct kinfo_vmentry *kve;
100 gdb::unique_xmalloc_ptr<struct kinfo_vmentry>
101 vmentl (kinfo_getvmmap (pid, &nitems));
103 perror_with_name (_("Couldn't fetch VM map entries."));
105 for (i = 0, kve = vmentl.get (); i < nitems; i++, kve++)
107 /* Skip unreadable segments and those where MAP_NOCORE has been set. */
108 if (!(kve->kve_protection & KVME_PROT_READ)
109 || kve->kve_flags & KVME_FLAG_NOCOREDUMP)
112 /* Skip segments with an invalid type. */
113 if (kve->kve_type != KVME_TYPE_DEFAULT
114 && kve->kve_type != KVME_TYPE_VNODE
115 && kve->kve_type != KVME_TYPE_SWAP
116 && kve->kve_type != KVME_TYPE_PHYS)
119 size = kve->kve_end - kve->kve_start;
122 fprintf_filtered (gdb_stdout,
123 "Save segment, %ld bytes at %s (%c%c%c)\n",
125 paddress (target_gdbarch (), kve->kve_start),
126 kve->kve_protection & KVME_PROT_READ ? 'r' : '-',
127 kve->kve_protection & KVME_PROT_WRITE ? 'w' : '-',
128 kve->kve_protection & KVME_PROT_EXEC ? 'x' : '-');
131 /* Invoke the callback function to create the corefile segment.
132 Pass MODIFIED as true, we do not know the real modification state. */
133 func (kve->kve_start, size, kve->kve_protection & KVME_PROT_READ,
134 kve->kve_protection & KVME_PROT_WRITE,
135 kve->kve_protection & KVME_PROT_EXEC, 1, obfd);
141 fbsd_read_mapping (FILE *mapfile, unsigned long *start, unsigned long *end,
144 /* FreeBSD 5.1-RELEASE uses a 256-byte buffer. */
146 int resident, privateresident;
150 /* As of FreeBSD 5.0-RELEASE, the layout is described in
151 /usr/src/sys/fs/procfs/procfs_map.c. Somewhere in 5.1-CURRENT a
152 new column was added to the procfs map. Therefore we can't use
153 fscanf since we need to support older releases too. */
154 if (fgets (buf, sizeof buf, mapfile) != NULL)
155 ret = sscanf (buf, "%lx %lx %d %d %lx %s", start, end,
156 &resident, &privateresident, &obj, protection);
158 return (ret != 0 && ret != EOF);
161 /* Iterate over all the memory regions in the current inferior,
162 calling FUNC for each memory region. OBFD is passed as the last
166 fbsd_nat_target::find_memory_regions (find_memory_region_ftype func,
169 pid_t pid = inferior_ptid.pid ();
170 unsigned long start, end, size;
172 int read, write, exec;
174 std::string mapfilename = string_printf ("/proc/%ld/map", (long) pid);
175 gdb_file_up mapfile (fopen (mapfilename.c_str (), "r"));
177 error (_("Couldn't open %s."), mapfilename.c_str ());
180 fprintf_filtered (gdb_stdout,
181 "Reading memory regions from %s\n", mapfilename.c_str ());
183 /* Now iterate until end-of-file. */
184 while (fbsd_read_mapping (mapfile.get (), &start, &end, &protection[0]))
188 read = (strchr (protection, 'r') != 0);
189 write = (strchr (protection, 'w') != 0);
190 exec = (strchr (protection, 'x') != 0);
194 fprintf_filtered (gdb_stdout,
195 "Save segment, %ld bytes at %s (%c%c%c)\n",
196 size, paddress (target_gdbarch (), start),
202 /* Invoke the callback function to create the corefile segment.
203 Pass MODIFIED as true, we do not know the real modification state. */
204 func (start, size, read, write, exec, 1, obfd);
211 /* Fetch the command line for a running process. */
213 static gdb::unique_xmalloc_ptr<char>
214 fbsd_fetch_cmdline (pid_t pid)
222 mib[2] = KERN_PROC_ARGS;
224 if (sysctl (mib, 4, NULL, &len, NULL, 0) == -1)
230 gdb::unique_xmalloc_ptr<char> cmdline ((char *) xmalloc (len));
231 if (sysctl (mib, 4, cmdline.get (), &len, NULL, 0) == -1)
237 /* Fetch the external variant of the kernel's internal process
238 structure for the process PID into KP. */
241 fbsd_fetch_kinfo_proc (pid_t pid, struct kinfo_proc *kp)
249 mib[2] = KERN_PROC_PID;
251 return (sysctl (mib, 4, kp, &len, NULL, 0) == 0);
254 /* Implement the "info_proc" target_ops method. */
257 fbsd_nat_target::info_proc (const char *args, enum info_proc_what what)
259 #ifdef HAVE_KINFO_GETFILE
260 gdb::unique_xmalloc_ptr<struct kinfo_file> fdtbl;
263 struct kinfo_proc kp;
265 bool do_cmdline = false;
268 #ifdef HAVE_KINFO_GETVMMAP
269 bool do_mappings = false;
271 bool do_status = false;
280 #ifdef HAVE_KINFO_GETVMMAP
302 #ifdef HAVE_KINFO_GETVMMAP
308 error (_("Not supported on this target."));
311 gdb_argv built_argv (args);
312 if (built_argv.count () == 0)
314 pid = inferior_ptid.pid ();
316 error (_("No current process: you must name one."));
318 else if (built_argv.count () == 1 && isdigit (built_argv[0][0]))
319 pid = strtol (built_argv[0], NULL, 10);
321 error (_("Invalid arguments."));
323 printf_filtered (_("process %d\n"), pid);
324 #ifdef HAVE_KINFO_GETFILE
325 if (do_cwd || do_exe)
326 fdtbl.reset (kinfo_getfile (pid, &nfd));
331 gdb::unique_xmalloc_ptr<char> cmdline = fbsd_fetch_cmdline (pid);
332 if (cmdline != nullptr)
333 printf_filtered ("cmdline = '%s'\n", cmdline.get ());
335 warning (_("unable to fetch command line"));
339 const char *cwd = NULL;
340 #ifdef HAVE_KINFO_GETFILE
341 struct kinfo_file *kf = fdtbl.get ();
342 for (int i = 0; i < nfd; i++, kf++)
344 if (kf->kf_type == KF_TYPE_VNODE && kf->kf_fd == KF_FD_TYPE_CWD)
352 printf_filtered ("cwd = '%s'\n", cwd);
354 warning (_("unable to fetch current working directory"));
358 const char *exe = NULL;
359 #ifdef HAVE_KINFO_GETFILE
360 struct kinfo_file *kf = fdtbl.get ();
361 for (int i = 0; i < nfd; i++, kf++)
363 if (kf->kf_type == KF_TYPE_VNODE && kf->kf_fd == KF_FD_TYPE_TEXT)
371 exe = pid_to_exec_file (pid);
373 printf_filtered ("exe = '%s'\n", exe);
375 warning (_("unable to fetch executable path name"));
377 #ifdef HAVE_KINFO_GETVMMAP
381 gdb::unique_xmalloc_ptr<struct kinfo_vmentry>
382 vmentl (kinfo_getvmmap (pid, &nvment));
384 if (vmentl != nullptr)
386 printf_filtered (_("Mapped address spaces:\n\n"));
388 printf_filtered (" %18s %18s %10s %10s %9s %s\n",
391 " Size", " Offset", "Flags ", "File");
393 printf_filtered ("\t%10s %10s %10s %10s %9s %s\n",
396 " Size", " Offset", "Flags ", "File");
399 struct kinfo_vmentry *kve = vmentl.get ();
400 for (int i = 0; i < nvment; i++, kve++)
404 start = kve->kve_start;
407 printf_filtered (" %18s %18s %10s %10s %9s %s\n",
410 hex_string (end - start),
411 hex_string (kve->kve_offset),
412 fbsd_vm_map_entry_flags (kve->kve_flags,
413 kve->kve_protection),
416 printf_filtered ("\t%10s %10s %10s %10s %9s %s\n",
419 hex_string (end - start),
420 hex_string (kve->kve_offset),
421 fbsd_vm_map_entry_flags (kve->kve_flags,
422 kve->kve_protection),
428 warning (_("unable to fetch virtual memory map"));
433 if (!fbsd_fetch_kinfo_proc (pid, &kp))
434 warning (_("Failed to fetch process information"));
440 printf_filtered ("Name: %s\n", kp.ki_comm);
447 state = "R (running)";
450 state = "T (stopped)";
453 state = "Z (zombie)";
456 state = "S (sleeping)";
459 state = "W (interrupt wait)";
462 state = "L (blocked on lock)";
465 state = "? (unknown)";
468 printf_filtered ("State: %s\n", state);
469 printf_filtered ("Parent process: %d\n", kp.ki_ppid);
470 printf_filtered ("Process group: %d\n", kp.ki_pgid);
471 printf_filtered ("Session id: %d\n", kp.ki_sid);
472 printf_filtered ("TTY: %ju\n", (uintmax_t) kp.ki_tdev);
473 printf_filtered ("TTY owner process group: %d\n", kp.ki_tpgid);
474 printf_filtered ("User IDs (real, effective, saved): %d %d %d\n",
475 kp.ki_ruid, kp.ki_uid, kp.ki_svuid);
476 printf_filtered ("Group IDs (real, effective, saved): %d %d %d\n",
477 kp.ki_rgid, kp.ki_groups[0], kp.ki_svgid);
478 printf_filtered ("Groups: ");
479 for (int i = 0; i < kp.ki_ngroups; i++)
480 printf_filtered ("%d ", kp.ki_groups[i]);
481 printf_filtered ("\n");
482 printf_filtered ("Minor faults (no memory page): %ld\n",
483 kp.ki_rusage.ru_minflt);
484 printf_filtered ("Minor faults, children: %ld\n",
485 kp.ki_rusage_ch.ru_minflt);
486 printf_filtered ("Major faults (memory page faults): %ld\n",
487 kp.ki_rusage.ru_majflt);
488 printf_filtered ("Major faults, children: %ld\n",
489 kp.ki_rusage_ch.ru_majflt);
490 printf_filtered ("utime: %jd.%06ld\n",
491 (intmax_t) kp.ki_rusage.ru_utime.tv_sec,
492 kp.ki_rusage.ru_utime.tv_usec);
493 printf_filtered ("stime: %jd.%06ld\n",
494 (intmax_t) kp.ki_rusage.ru_stime.tv_sec,
495 kp.ki_rusage.ru_stime.tv_usec);
496 printf_filtered ("utime, children: %jd.%06ld\n",
497 (intmax_t) kp.ki_rusage_ch.ru_utime.tv_sec,
498 kp.ki_rusage_ch.ru_utime.tv_usec);
499 printf_filtered ("stime, children: %jd.%06ld\n",
500 (intmax_t) kp.ki_rusage_ch.ru_stime.tv_sec,
501 kp.ki_rusage_ch.ru_stime.tv_usec);
502 printf_filtered ("'nice' value: %d\n", kp.ki_nice);
503 printf_filtered ("Start time: %jd.%06ld\n", kp.ki_start.tv_sec,
504 kp.ki_start.tv_usec);
505 pgtok = getpagesize () / 1024;
506 printf_filtered ("Virtual memory size: %ju kB\n",
507 (uintmax_t) kp.ki_size / 1024);
508 printf_filtered ("Data size: %ju kB\n",
509 (uintmax_t) kp.ki_dsize * pgtok);
510 printf_filtered ("Stack size: %ju kB\n",
511 (uintmax_t) kp.ki_ssize * pgtok);
512 printf_filtered ("Text size: %ju kB\n",
513 (uintmax_t) kp.ki_tsize * pgtok);
514 printf_filtered ("Resident set size: %ju kB\n",
515 (uintmax_t) kp.ki_rssize * pgtok);
516 printf_filtered ("Maximum RSS: %ju kB\n",
517 (uintmax_t) kp.ki_rusage.ru_maxrss);
518 printf_filtered ("Pending Signals: ");
519 for (int i = 0; i < _SIG_WORDS; i++)
520 printf_filtered ("%08x ", kp.ki_siglist.__bits[i]);
521 printf_filtered ("\n");
522 printf_filtered ("Ignored Signals: ");
523 for (int i = 0; i < _SIG_WORDS; i++)
524 printf_filtered ("%08x ", kp.ki_sigignore.__bits[i]);
525 printf_filtered ("\n");
526 printf_filtered ("Caught Signals: ");
527 for (int i = 0; i < _SIG_WORDS; i++)
528 printf_filtered ("%08x ", kp.ki_sigcatch.__bits[i]);
529 printf_filtered ("\n");
536 #ifdef KERN_PROC_AUXV
539 /* Return the size of siginfo for the current inferior. */
547 /* This structure matches the naming and layout of `siginfo_t' in
548 <sys/signal.h>. In particular, the `si_foo' macros defined in that
549 header can be used with both types to copy fields in the `_reason'
561 union sigval32 si_value;
594 struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
596 /* Is the inferior 32-bit? If so, use the 32-bit siginfo size. */
597 if (gdbarch_long_bit (gdbarch) == 32)
598 return sizeof (struct siginfo32);
600 return sizeof (siginfo_t);
603 /* Convert a native 64-bit siginfo object to a 32-bit object. Note
604 that FreeBSD doesn't support writing to $_siginfo, so this only
605 needs to convert one way. */
608 fbsd_convert_siginfo (siginfo_t *si)
611 struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
613 /* Is the inferior 32-bit? If not, nothing to do. */
614 if (gdbarch_long_bit (gdbarch) != 32)
617 struct siginfo32 si32;
619 si32.si_signo = si->si_signo;
620 si32.si_errno = si->si_errno;
621 si32.si_code = si->si_code;
622 si32.si_pid = si->si_pid;
623 si32.si_uid = si->si_uid;
624 si32.si_status = si->si_status;
625 si32.si_addr = (uintptr_t) si->si_addr;
627 /* If sival_ptr is being used instead of sival_int on a big-endian
628 platform, then sival_int will be zero since it holds the upper
629 32-bits of the pointer value. */
630 #if _BYTE_ORDER == _BIG_ENDIAN
631 if (si->si_value.sival_int == 0)
632 si32.si_value.sival_ptr = (uintptr_t) si->si_value.sival_ptr;
634 si32.si_value.sival_int = si->si_value.sival_int;
636 si32.si_value.sival_int = si->si_value.sival_int;
639 /* Always copy the spare fields and then possibly overwrite them for
640 signal-specific or code-specific fields. */
641 si32._reason.__spare__.__spare1__ = si->_reason.__spare__.__spare1__;
642 for (int i = 0; i < 7; i++)
643 si32._reason.__spare__.__spare2__[i] = si->_reason.__spare__.__spare2__[i];
644 switch (si->si_signo) {
649 si32.si_trapno = si->si_trapno;
652 switch (si->si_code) {
654 si32.si_timerid = si->si_timerid;
655 si32.si_overrun = si->si_overrun;
658 si32.si_mqd = si->si_mqd;
662 memcpy(si, &si32, sizeof (si32));
667 /* Implement the "xfer_partial" target_ops method. */
669 enum target_xfer_status
670 fbsd_nat_target::xfer_partial (enum target_object object,
671 const char *annex, gdb_byte *readbuf,
672 const gdb_byte *writebuf,
673 ULONGEST offset, ULONGEST len,
674 ULONGEST *xfered_len)
676 pid_t pid = inferior_ptid.pid ();
681 case TARGET_OBJECT_SIGNAL_INFO:
683 struct ptrace_lwpinfo pl;
686 /* FreeBSD doesn't support writing to $_siginfo. */
687 if (writebuf != NULL)
688 return TARGET_XFER_E_IO;
690 if (inferior_ptid.lwp_p ())
691 pid = inferior_ptid.lwp ();
693 siginfo_size = fbsd_siginfo_size ();
694 if (offset > siginfo_size)
695 return TARGET_XFER_E_IO;
697 if (ptrace (PT_LWPINFO, pid, (PTRACE_TYPE_ARG3) &pl, sizeof (pl)) == -1)
698 return TARGET_XFER_E_IO;
700 if (!(pl.pl_flags & PL_FLAG_SI))
701 return TARGET_XFER_E_IO;
703 fbsd_convert_siginfo (&pl.pl_siginfo);
704 if (offset + len > siginfo_size)
705 len = siginfo_size - offset;
707 memcpy (readbuf, ((gdb_byte *) &pl.pl_siginfo) + offset, len);
709 return TARGET_XFER_OK;
712 case TARGET_OBJECT_AUXV:
714 gdb::byte_vector buf_storage;
719 if (writebuf != NULL)
720 return TARGET_XFER_E_IO;
723 mib[2] = KERN_PROC_AUXV;
732 buflen = offset + len;
733 buf_storage.resize (buflen);
734 buf = buf_storage.data ();
736 if (sysctl (mib, 4, buf, &buflen, NULL, 0) == 0)
743 memcpy (readbuf, buf + offset, buflen);
748 *xfered_len = buflen;
749 return (buflen == 0) ? TARGET_XFER_EOF : TARGET_XFER_OK;
751 return TARGET_XFER_E_IO;
753 case TARGET_OBJECT_FREEBSD_VMMAP:
754 case TARGET_OBJECT_FREEBSD_PS_STRINGS:
756 gdb::byte_vector buf_storage;
762 uint32_t struct_size;
765 case TARGET_OBJECT_FREEBSD_VMMAP:
766 proc_target = KERN_PROC_VMMAP;
767 struct_size = sizeof (struct kinfo_vmentry);
769 case TARGET_OBJECT_FREEBSD_PS_STRINGS:
770 proc_target = KERN_PROC_PS_STRINGS;
771 struct_size = sizeof (void *);
775 if (writebuf != NULL)
776 return TARGET_XFER_E_IO;
780 mib[2] = proc_target;
783 if (sysctl (mib, 4, NULL, &buflen, NULL, 0) != 0)
784 return TARGET_XFER_E_IO;
785 buflen += sizeof (struct_size);
787 if (offset >= buflen)
790 return TARGET_XFER_EOF;
793 buf_storage.resize (buflen);
794 buf = buf_storage.data ();
796 memcpy (buf, &struct_size, sizeof (struct_size));
797 buflen -= sizeof (struct_size);
798 if (sysctl (mib, 4, buf + sizeof (struct_size), &buflen, NULL, 0) != 0)
799 return TARGET_XFER_E_IO;
800 buflen += sizeof (struct_size);
802 if (buflen - offset < len)
803 len = buflen - offset;
804 memcpy (readbuf, buf + offset, len);
806 return TARGET_XFER_OK;
809 return inf_ptrace_target::xfer_partial (object, annex,
810 readbuf, writebuf, offset,
817 static int debug_fbsd_lwp;
818 static int debug_fbsd_nat;
821 show_fbsd_lwp_debug (struct ui_file *file, int from_tty,
822 struct cmd_list_element *c, const char *value)
824 fprintf_filtered (file, _("Debugging of FreeBSD lwp module is %s.\n"), value);
828 show_fbsd_nat_debug (struct ui_file *file, int from_tty,
829 struct cmd_list_element *c, const char *value)
831 fprintf_filtered (file, _("Debugging of FreeBSD native target is %s.\n"),
836 FreeBSD's first thread support was via a "reentrant" version of libc
837 (libc_r) that first shipped in 2.2.7. This library multiplexed all
838 of the threads in a process onto a single kernel thread. This
839 library was supported via the bsd-uthread target.
841 FreeBSD 5.1 introduced two new threading libraries that made use of
842 multiple kernel threads. The first (libkse) scheduled M user
843 threads onto N (<= M) kernel threads (LWPs). The second (libthr)
844 bound each user thread to a dedicated kernel thread. libkse shipped
845 as the default threading library (libpthread).
847 FreeBSD 5.3 added a libthread_db to abstract the interface across
848 the various thread libraries (libc_r, libkse, and libthr).
850 FreeBSD 7.0 switched the default threading library from from libkse
851 to libpthread and removed libc_r.
853 FreeBSD 8.0 removed libkse and the in-kernel support for it. The
854 only threading library supported by 8.0 and later is libthr which
855 ties each user thread directly to an LWP. To simplify the
856 implementation, this target only supports LWP-backed threads using
857 ptrace directly rather than libthread_db.
859 FreeBSD 11.0 introduced LWP event reporting via PT_LWP_EVENTS.
862 /* Return true if PTID is still active in the inferior. */
865 fbsd_nat_target::thread_alive (ptid_t ptid)
869 struct ptrace_lwpinfo pl;
871 if (ptrace (PT_LWPINFO, ptid.lwp (), (caddr_t) &pl, sizeof pl)
874 #ifdef PL_FLAG_EXITED
875 if (pl.pl_flags & PL_FLAG_EXITED)
883 /* Convert PTID to a string. Returns the string in a static
887 fbsd_nat_target::pid_to_str (ptid_t ptid)
895 int pid = ptid.pid ();
897 xsnprintf (buf, sizeof buf, "LWP %d of process %d", lwp, pid);
901 return normal_pid_to_str (ptid);
904 #ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME
905 /* Return the name assigned to a thread by an application. Returns
906 the string in a static buffer. */
909 fbsd_nat_target::thread_name (struct thread_info *thr)
911 struct ptrace_lwpinfo pl;
912 struct kinfo_proc kp;
913 int pid = thr->ptid.pid ();
914 long lwp = thr->ptid.lwp ();
915 static char buf[sizeof pl.pl_tdname + 1];
917 /* Note that ptrace_lwpinfo returns the process command in pl_tdname
918 if a name has not been set explicitly. Return a NULL name in
920 if (!fbsd_fetch_kinfo_proc (pid, &kp))
921 perror_with_name (_("Failed to fetch process information"));
922 if (ptrace (PT_LWPINFO, lwp, (caddr_t) &pl, sizeof pl) == -1)
923 perror_with_name (("ptrace"));
924 if (strcmp (kp.ki_comm, pl.pl_tdname) == 0)
926 xsnprintf (buf, sizeof buf, "%s", pl.pl_tdname);
931 /* Enable additional event reporting on new processes.
933 To catch fork events, PTRACE_FORK is set on every traced process
934 to enable stops on returns from fork or vfork. Note that both the
935 parent and child will always stop, even if system call stops are
938 To catch LWP events, PTRACE_EVENTS is set on every traced process.
939 This enables stops on the birth for new LWPs (excluding the "main" LWP)
940 and the death of LWPs (excluding the last LWP in a process). Note
941 that unlike fork events, the LWP that creates a new LWP does not
945 fbsd_enable_proc_events (pid_t pid)
947 #ifdef PT_GET_EVENT_MASK
950 if (ptrace (PT_GET_EVENT_MASK, pid, (PTRACE_TYPE_ARG3)&events,
951 sizeof (events)) == -1)
952 perror_with_name (("ptrace"));
953 events |= PTRACE_FORK | PTRACE_LWP;
955 events |= PTRACE_VFORK;
957 if (ptrace (PT_SET_EVENT_MASK, pid, (PTRACE_TYPE_ARG3)&events,
958 sizeof (events)) == -1)
959 perror_with_name (("ptrace"));
962 if (ptrace (PT_FOLLOW_FORK, pid, (PTRACE_TYPE_ARG3)0, 1) == -1)
963 perror_with_name (("ptrace"));
966 if (ptrace (PT_LWP_EVENTS, pid, (PTRACE_TYPE_ARG3)0, 1) == -1)
967 perror_with_name (("ptrace"));
972 /* Add threads for any new LWPs in a process.
974 When LWP events are used, this function is only used to detect existing
975 threads when attaching to a process. On older systems, this function is
976 called to discover new threads each time the thread list is updated. */
979 fbsd_add_threads (pid_t pid)
983 gdb_assert (!in_thread_list (ptid_t (pid)));
984 nlwps = ptrace (PT_GETNUMLWPS, pid, NULL, 0);
986 perror_with_name (("ptrace"));
988 gdb::unique_xmalloc_ptr<lwpid_t[]> lwps (XCNEWVEC (lwpid_t, nlwps));
990 nlwps = ptrace (PT_GETLWPLIST, pid, (caddr_t) lwps.get (), nlwps);
992 perror_with_name (("ptrace"));
994 for (i = 0; i < nlwps; i++)
996 ptid_t ptid = ptid_t (pid, lwps[i], 0);
998 if (!in_thread_list (ptid))
1000 #ifdef PT_LWP_EVENTS
1001 struct ptrace_lwpinfo pl;
1003 /* Don't add exited threads. Note that this is only called
1004 when attaching to a multi-threaded process. */
1005 if (ptrace (PT_LWPINFO, lwps[i], (caddr_t) &pl, sizeof pl) == -1)
1006 perror_with_name (("ptrace"));
1007 if (pl.pl_flags & PL_FLAG_EXITED)
1011 fprintf_unfiltered (gdb_stdlog,
1012 "FLWP: adding thread for LWP %u\n",
1019 /* Implement the "update_thread_list" target_ops method. */
1022 fbsd_nat_target::update_thread_list ()
1024 #ifdef PT_LWP_EVENTS
1025 /* With support for thread events, threads are added/deleted from the
1026 list as events are reported, so just try deleting exited threads. */
1027 delete_exited_threads ();
1031 fbsd_add_threads (inferior_ptid.pid ());
1037 To catch fork events, PT_FOLLOW_FORK is set on every traced process
1038 to enable stops on returns from fork or vfork. Note that both the
1039 parent and child will always stop, even if system call stops are not
1042 After a fork, both the child and parent process will stop and report
1043 an event. However, there is no guarantee of order. If the parent
1044 reports its stop first, then fbsd_wait explicitly waits for the new
1045 child before returning. If the child reports its stop first, then
1046 the event is saved on a list and ignored until the parent's stop is
1047 reported. fbsd_wait could have been changed to fetch the parent PID
1048 of the new child and used that to wait for the parent explicitly.
1049 However, if two threads in the parent fork at the same time, then
1050 the wait on the parent might return the "wrong" fork event.
1052 The initial version of PT_FOLLOW_FORK did not set PL_FLAG_CHILD for
1053 the new child process. This flag could be inferred by treating any
1054 events for an unknown pid as a new child.
1056 In addition, the initial version of PT_FOLLOW_FORK did not report a
1057 stop event for the parent process of a vfork until after the child
1058 process executed a new program or exited. The kernel was changed to
1059 defer the wait for exit or exec of the child until after posting the
1060 stop event shortly after the change to introduce PL_FLAG_CHILD.
1061 This could be worked around by reporting a vfork event when the
1062 child event posted and ignoring the subsequent event from the
1065 This implementation requires both of these fixes for simplicity's
1066 sake. FreeBSD versions newer than 9.1 contain both fixes.
1069 static std::list<ptid_t> fbsd_pending_children;
1071 /* Record a new child process event that is reported before the
1072 corresponding fork event in the parent. */
1075 fbsd_remember_child (ptid_t pid)
1077 fbsd_pending_children.push_front (pid);
1080 /* Check for a previously-recorded new child process event for PID.
1081 If one is found, remove it from the list and return the PTID. */
1084 fbsd_is_child_pending (pid_t pid)
1086 for (auto it = fbsd_pending_children.begin ();
1087 it != fbsd_pending_children.end (); it++)
1088 if (it->pid () == pid)
1091 fbsd_pending_children.erase (it);
1097 #ifndef PTRACE_VFORK
1098 static std::forward_list<ptid_t> fbsd_pending_vfork_done;
1100 /* Record a pending vfork done event. */
1103 fbsd_add_vfork_done (ptid_t pid)
1105 fbsd_pending_vfork_done.push_front (pid);
1108 /* Check for a pending vfork done event for a specific PID. */
1111 fbsd_is_vfork_done_pending (pid_t pid)
1113 for (auto it = fbsd_pending_vfork_done.begin ();
1114 it != fbsd_pending_vfork_done.end (); it++)
1115 if (it->pid () == pid)
1120 /* Check for a pending vfork done event. If one is found, remove it
1121 from the list and return the PTID. */
1124 fbsd_next_vfork_done (void)
1126 if (!fbsd_pending_vfork_done.empty ())
1128 ptid_t ptid = fbsd_pending_vfork_done.front ();
1129 fbsd_pending_vfork_done.pop_front ();
1137 /* Implement the "resume" target_ops method. */
1140 fbsd_nat_target::resume (ptid_t ptid, int step, enum gdb_signal signo)
1142 #if defined(TDP_RFPPWAIT) && !defined(PTRACE_VFORK)
1145 /* Don't PT_CONTINUE a process which has a pending vfork done event. */
1146 if (minus_one_ptid == ptid)
1147 pid = inferior_ptid.pid ();
1150 if (fbsd_is_vfork_done_pending (pid))
1155 fprintf_unfiltered (gdb_stdlog,
1156 "FLWP: fbsd_resume for ptid (%d, %ld, %ld)\n",
1157 ptid.pid (), ptid.lwp (),
1161 /* If ptid is a specific LWP, suspend all other LWPs in the process. */
1162 struct thread_info *tp;
1165 ALL_NON_EXITED_THREADS (tp)
1167 if (tp->ptid.pid () != ptid.pid ())
1170 if (tp->ptid.lwp () == ptid.lwp ())
1171 request = PT_RESUME;
1173 request = PT_SUSPEND;
1175 if (ptrace (request, tp->ptid.lwp (), NULL, 0) == -1)
1176 perror_with_name (("ptrace"));
1181 /* If ptid is a wildcard, resume all matching threads (they won't run
1182 until the process is continued however). */
1183 struct thread_info *tp;
1185 ALL_NON_EXITED_THREADS (tp)
1187 if (!tp->ptid.matches (ptid))
1190 if (ptrace (PT_RESUME, tp->ptid.lwp (), NULL, 0) == -1)
1191 perror_with_name (("ptrace"));
1193 ptid = inferior_ptid;
1196 #if __FreeBSD_version < 1200052
1197 /* When multiple threads within a process wish to report STOPPED
1198 events from wait(), the kernel picks one thread event as the
1199 thread event to report. The chosen thread event is retrieved via
1200 PT_LWPINFO by passing the process ID as the request pid. If
1201 multiple events are pending, then the subsequent wait() after
1202 resuming a process will report another STOPPED event after
1203 resuming the process to handle the next thread event and so on.
1205 A single thread event is cleared as a side effect of resuming the
1206 process with PT_CONTINUE, PT_STEP, etc. In older kernels,
1207 however, the request pid was used to select which thread's event
1208 was cleared rather than always clearing the event that was just
1209 reported. To avoid clearing the event of the wrong LWP, always
1210 pass the process ID instead of an LWP ID to PT_CONTINUE or
1213 In the case of stepping, the process ID cannot be used with
1214 PT_STEP since it would step the thread that reported an event
1215 which may not be the thread indicated by PTID. For stepping, use
1216 PT_SETSTEP to enable stepping on the desired thread before
1217 resuming the process via PT_CONTINUE instead of using
1221 if (ptrace (PT_SETSTEP, get_ptrace_pid (ptid), NULL, 0) == -1)
1222 perror_with_name (("ptrace"));
1225 ptid = ptid_t (ptid.pid ());
1227 inf_ptrace_target::resume (ptid, step, signo);
1230 #ifdef USE_SIGTRAP_SIGINFO
1231 /* Handle breakpoint and trace traps reported via SIGTRAP. If the
1232 trap was a breakpoint or trace trap that should be reported to the
1233 core, return true. */
1236 fbsd_handle_debug_trap (ptid_t ptid, const struct ptrace_lwpinfo &pl)
1239 /* Ignore traps without valid siginfo or for signals other than
1241 if (! (pl.pl_flags & PL_FLAG_SI) || pl.pl_siginfo.si_signo != SIGTRAP)
1244 /* Trace traps are either a single step or a hardware watchpoint or
1246 if (pl.pl_siginfo.si_code == TRAP_TRACE)
1249 fprintf_unfiltered (gdb_stdlog,
1250 "FNAT: trace trap for LWP %ld\n", ptid.lwp ());
1254 if (pl.pl_siginfo.si_code == TRAP_BRKPT)
1256 /* Fixup PC for the software breakpoint. */
1257 struct regcache *regcache = get_thread_regcache (ptid);
1258 struct gdbarch *gdbarch = regcache->arch ();
1259 int decr_pc = gdbarch_decr_pc_after_break (gdbarch);
1262 fprintf_unfiltered (gdb_stdlog,
1263 "FNAT: sw breakpoint trap for LWP %ld\n",
1269 pc = regcache_read_pc (regcache);
1270 regcache_write_pc (regcache, pc - decr_pc);
1279 /* Wait for the child specified by PTID to do something. Return the
1280 process ID of the child, or MINUS_ONE_PTID in case of error; store
1281 the status in *OURSTATUS. */
1284 fbsd_nat_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus,
1291 #ifndef PTRACE_VFORK
1292 wptid = fbsd_next_vfork_done ();
1293 if (wptid != null_ptid)
1295 ourstatus->kind = TARGET_WAITKIND_VFORK_DONE;
1299 wptid = inf_ptrace_target::wait (ptid, ourstatus, target_options);
1300 if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
1302 struct ptrace_lwpinfo pl;
1307 if (ptrace (PT_LWPINFO, pid, (caddr_t) &pl, sizeof pl) == -1)
1308 perror_with_name (("ptrace"));
1310 wptid = ptid_t (pid, pl.pl_lwpid, 0);
1314 fprintf_unfiltered (gdb_stdlog,
1315 "FNAT: stop for LWP %u event %d flags %#x\n",
1316 pl.pl_lwpid, pl.pl_event, pl.pl_flags);
1317 if (pl.pl_flags & PL_FLAG_SI)
1318 fprintf_unfiltered (gdb_stdlog,
1319 "FNAT: si_signo %u si_code %u\n",
1320 pl.pl_siginfo.si_signo,
1321 pl.pl_siginfo.si_code);
1324 #ifdef PT_LWP_EVENTS
1325 if (pl.pl_flags & PL_FLAG_EXITED)
1327 /* If GDB attaches to a multi-threaded process, exiting
1328 threads might be skipped during post_attach that
1329 have not yet reported their PL_FLAG_EXITED event.
1330 Ignore EXITED events for an unknown LWP. */
1331 thread_info *thr = find_thread_ptid (wptid);
1335 fprintf_unfiltered (gdb_stdlog,
1336 "FLWP: deleting thread for LWP %u\n",
1338 if (print_thread_events)
1339 printf_unfiltered (_("[%s exited]\n"), target_pid_to_str
1341 delete_thread (thr);
1343 if (ptrace (PT_CONTINUE, pid, (caddr_t) 1, 0) == -1)
1344 perror_with_name (("ptrace"));
1349 /* Switch to an LWP PTID on the first stop in a new process.
1350 This is done after handling PL_FLAG_EXITED to avoid
1351 switching to an exited LWP. It is done before checking
1352 PL_FLAG_BORN in case the first stop reported after
1353 attaching to an existing process is a PL_FLAG_BORN
1355 if (in_thread_list (ptid_t (pid)))
1358 fprintf_unfiltered (gdb_stdlog,
1359 "FLWP: using LWP %u for first thread\n",
1361 thread_change_ptid (ptid_t (pid), wptid);
1364 #ifdef PT_LWP_EVENTS
1365 if (pl.pl_flags & PL_FLAG_BORN)
1367 /* If GDB attaches to a multi-threaded process, newborn
1368 threads might be added by fbsd_add_threads that have
1369 not yet reported their PL_FLAG_BORN event. Ignore
1370 BORN events for an already-known LWP. */
1371 if (!in_thread_list (wptid))
1374 fprintf_unfiltered (gdb_stdlog,
1375 "FLWP: adding thread for LWP %u\n",
1379 ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
1385 if (pl.pl_flags & PL_FLAG_FORKED)
1387 #ifndef PTRACE_VFORK
1388 struct kinfo_proc kp;
1393 child = pl.pl_child_pid;
1394 ourstatus->kind = TARGET_WAITKIND_FORKED;
1396 if (pl.pl_flags & PL_FLAG_VFORKED)
1397 ourstatus->kind = TARGET_WAITKIND_VFORKED;
1400 /* Make sure the other end of the fork is stopped too. */
1401 child_ptid = fbsd_is_child_pending (child);
1402 if (child_ptid == null_ptid)
1404 pid = waitpid (child, &status, 0);
1406 perror_with_name (("waitpid"));
1408 gdb_assert (pid == child);
1410 if (ptrace (PT_LWPINFO, child, (caddr_t)&pl, sizeof pl) == -1)
1411 perror_with_name (("ptrace"));
1413 gdb_assert (pl.pl_flags & PL_FLAG_CHILD);
1414 child_ptid = ptid_t (child, pl.pl_lwpid, 0);
1417 /* Enable additional events on the child process. */
1418 fbsd_enable_proc_events (child_ptid.pid ());
1420 #ifndef PTRACE_VFORK
1421 /* For vfork, the child process will have the P_PPWAIT
1423 if (fbsd_fetch_kinfo_proc (child, &kp))
1425 if (kp.ki_flag & P_PPWAIT)
1426 ourstatus->kind = TARGET_WAITKIND_VFORKED;
1429 warning (_("Failed to fetch process information"));
1431 ourstatus->value.related_pid = child_ptid;
1436 if (pl.pl_flags & PL_FLAG_CHILD)
1438 /* Remember that this child forked, but do not report it
1439 until the parent reports its corresponding fork
1441 fbsd_remember_child (wptid);
1446 if (pl.pl_flags & PL_FLAG_VFORK_DONE)
1448 ourstatus->kind = TARGET_WAITKIND_VFORK_DONE;
1455 if (pl.pl_flags & PL_FLAG_EXEC)
1457 ourstatus->kind = TARGET_WAITKIND_EXECD;
1458 ourstatus->value.execd_pathname
1459 = xstrdup (pid_to_exec_file (pid));
1464 #ifdef USE_SIGTRAP_SIGINFO
1465 if (fbsd_handle_debug_trap (wptid, pl))
1469 /* Note that PL_FLAG_SCE is set for any event reported while
1470 a thread is executing a system call in the kernel. In
1471 particular, signals that interrupt a sleep in a system
1472 call will report this flag as part of their event. Stops
1473 explicitly for system call entry and exit always use
1474 SIGTRAP, so only treat SIGTRAP events as system call
1475 entry/exit events. */
1476 if (pl.pl_flags & (PL_FLAG_SCE | PL_FLAG_SCX)
1477 && ourstatus->value.sig == SIGTRAP)
1479 #ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_SYSCALL_CODE
1480 if (catch_syscall_enabled ())
1482 if (catching_syscall_number (pl.pl_syscall_code))
1484 if (pl.pl_flags & PL_FLAG_SCE)
1485 ourstatus->kind = TARGET_WAITKIND_SYSCALL_ENTRY;
1487 ourstatus->kind = TARGET_WAITKIND_SYSCALL_RETURN;
1488 ourstatus->value.syscall_number = pl.pl_syscall_code;
1493 /* If the core isn't interested in this event, just
1494 continue the process explicitly and wait for another
1495 event. Note that PT_SYSCALL is "sticky" on FreeBSD
1496 and once system call stops are enabled on a process
1497 it stops for all system call entries and exits. */
1498 if (ptrace (PT_CONTINUE, pid, (caddr_t) 1, 0) == -1)
1499 perror_with_name (("ptrace"));
1507 #ifdef USE_SIGTRAP_SIGINFO
1508 /* Implement the "stopped_by_sw_breakpoint" target_ops method. */
1511 fbsd_nat_target::stopped_by_sw_breakpoint ()
1513 struct ptrace_lwpinfo pl;
1515 if (ptrace (PT_LWPINFO, get_ptrace_pid (inferior_ptid), (caddr_t) &pl,
1519 return ((pl.pl_flags & PL_FLAG_SI)
1520 && pl.pl_siginfo.si_signo == SIGTRAP
1521 && pl.pl_siginfo.si_code == TRAP_BRKPT);
1524 /* Implement the "supports_stopped_by_sw_breakpoint" target_ops
1528 fbsd_nat_target::supports_stopped_by_sw_breakpoint ()
1535 /* Target hook for follow_fork. On entry and at return inferior_ptid is
1536 the ptid of the followed inferior. */
1539 fbsd_nat_target::follow_fork (int follow_child, int detach_fork)
1541 if (!follow_child && detach_fork)
1543 struct thread_info *tp = inferior_thread ();
1544 pid_t child_pid = tp->pending_follow.value.related_pid.pid ();
1546 /* Breakpoints have already been detached from the child by
1549 if (ptrace (PT_DETACH, child_pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
1550 perror_with_name (("ptrace"));
1552 #ifndef PTRACE_VFORK
1553 if (tp->pending_follow.kind == TARGET_WAITKIND_VFORKED)
1555 /* We can't insert breakpoints until the child process has
1556 finished with the shared memory region. The parent
1557 process doesn't wait for the child process to exit or
1558 exec until after it has been resumed from the ptrace stop
1559 to report the fork. Once it has been resumed it doesn't
1560 stop again before returning to userland, so there is no
1561 reliable way to wait on the parent.
1563 We can't stay attached to the child to wait for an exec
1564 or exit because it may invoke ptrace(PT_TRACE_ME)
1565 (e.g. if the parent process is a debugger forking a new
1568 In the end, the best we can do is to make sure it runs
1569 for a little while. Hopefully it will be out of range of
1570 any breakpoints we reinsert. Usually this is only the
1571 single-step breakpoint at vfork's return point. */
1575 /* Schedule a fake VFORK_DONE event to report on the next
1577 fbsd_add_vfork_done (inferior_ptid);
1586 fbsd_nat_target::insert_fork_catchpoint (int pid)
1592 fbsd_nat_target::remove_fork_catchpoint (int pid)
1598 fbsd_nat_target::insert_vfork_catchpoint (int pid)
1604 fbsd_nat_target::remove_vfork_catchpoint (int pid)
1610 /* Implement the "post_startup_inferior" target_ops method. */
1613 fbsd_nat_target::post_startup_inferior (ptid_t pid)
1615 fbsd_enable_proc_events (pid.pid ());
1618 /* Implement the "post_attach" target_ops method. */
1621 fbsd_nat_target::post_attach (int pid)
1623 fbsd_enable_proc_events (pid);
1624 fbsd_add_threads (pid);
1628 /* If the FreeBSD kernel supports PL_FLAG_EXEC, then traced processes
1629 will always stop after exec. */
1632 fbsd_nat_target::insert_exec_catchpoint (int pid)
1638 fbsd_nat_target::remove_exec_catchpoint (int pid)
1644 #ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_SYSCALL_CODE
1646 fbsd_nat_target::set_syscall_catchpoint (int pid, bool needed,
1648 gdb::array_view<const int> syscall_counts)
1651 /* Ignore the arguments. inf-ptrace.c will use PT_SYSCALL which
1652 will catch all system call entries and exits. The system calls
1653 are filtered by GDB rather than the kernel. */
1660 _initialize_fbsd_nat (void)
1663 add_setshow_boolean_cmd ("fbsd-lwp", class_maintenance,
1664 &debug_fbsd_lwp, _("\
1665 Set debugging of FreeBSD lwp module."), _("\
1666 Show debugging of FreeBSD lwp module."), _("\
1667 Enables printf debugging output."),
1669 &show_fbsd_lwp_debug,
1670 &setdebuglist, &showdebuglist);
1671 add_setshow_boolean_cmd ("fbsd-nat", class_maintenance,
1672 &debug_fbsd_nat, _("\
1673 Set debugging of FreeBSD native target."), _("\
1674 Show debugging of FreeBSD native target."), _("\
1675 Enables printf debugging output."),
1677 &show_fbsd_nat_debug,
1678 &setdebuglist, &showdebuglist);