/* Native-dependent code for FreeBSD.
- Copyright (C) 2002, 2003, 2004, 2007 Free Software Foundation, Inc.
+ Copyright (C) 2002-2017 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
+#include "byte-vector.h"
#include "gdbcore.h"
#include "inferior.h"
#include "regcache.h"
#include "regset.h"
-
-#include "gdb_assert.h"
-#include "gdb_string.h"
+#include "gdbcmd.h"
+#include "gdbthread.h"
+#include "gdb_wait.h"
#include <sys/types.h>
#include <sys/procfs.h>
+#include <sys/ptrace.h>
+#include <sys/signal.h>
#include <sys/sysctl.h>
+#include <sys/user.h>
+#ifdef HAVE_KINFO_GETVMMAP
+#include <libutil.h>
+#else
+#include "filestuff.h"
+#endif
#include "elf-bfd.h"
#include "fbsd-nat.h"
-/* Return a the name of file that can be opened to get the symbols for
+#include <list>
+
+/* Return the name of a file that can be opened to get the symbols for
the child process identified by PID. */
-char *
-fbsd_pid_to_exec_file (int pid)
+static char *
+fbsd_pid_to_exec_file (struct target_ops *self, int pid)
{
- size_t len = MAXPATHLEN;
- char *buf = xcalloc (len, sizeof (char));
- char *path;
+ ssize_t len;
+ static char buf[PATH_MAX];
+ char name[PATH_MAX];
#ifdef KERN_PROC_PATHNAME
+ size_t buflen;
int mib[4];
mib[0] = CTL_KERN;
mib[1] = KERN_PROC;
mib[2] = KERN_PROC_PATHNAME;
mib[3] = pid;
- if (sysctl (mib, 4, buf, &len, NULL, 0) == 0)
+ buflen = sizeof buf;
+ if (sysctl (mib, 4, buf, &buflen, NULL, 0) == 0)
return buf;
#endif
- path = xstrprintf ("/proc/%d/file", pid);
- if (readlink (path, buf, MAXPATHLEN) == -1)
+ xsnprintf (name, PATH_MAX, "/proc/%d/exe", pid);
+ len = readlink (name, buf, PATH_MAX - 1);
+ if (len != -1)
{
- xfree (buf);
- buf = NULL;
+ buf[len] = '\0';
+ return buf;
}
- xfree (path);
- return buf;
+ return NULL;
}
+#ifdef HAVE_KINFO_GETVMMAP
+/* Deleter for std::unique_ptr that invokes free. */
+
+template <typename T>
+struct free_deleter
+{
+ void operator() (T *ptr) const { free (ptr); }
+};
+
+/* Iterate over all the memory regions in the current inferior,
+ calling FUNC for each memory region. OBFD is passed as the last
+ argument to FUNC. */
+
+static int
+fbsd_find_memory_regions (struct target_ops *self,
+ find_memory_region_ftype func, void *obfd)
+{
+ pid_t pid = ptid_get_pid (inferior_ptid);
+ struct kinfo_vmentry *kve;
+ uint64_t size;
+ int i, nitems;
+
+ std::unique_ptr<struct kinfo_vmentry, free_deleter<struct kinfo_vmentry>>
+ vmentl (kinfo_getvmmap (pid, &nitems));
+ if (vmentl == NULL)
+ perror_with_name (_("Couldn't fetch VM map entries."));
+
+ for (i = 0, kve = vmentl.get (); i < nitems; i++, kve++)
+ {
+ /* Skip unreadable segments and those where MAP_NOCORE has been set. */
+ if (!(kve->kve_protection & KVME_PROT_READ)
+ || kve->kve_flags & KVME_FLAG_NOCOREDUMP)
+ continue;
+
+ /* Skip segments with an invalid type. */
+ if (kve->kve_type != KVME_TYPE_DEFAULT
+ && kve->kve_type != KVME_TYPE_VNODE
+ && kve->kve_type != KVME_TYPE_SWAP
+ && kve->kve_type != KVME_TYPE_PHYS)
+ continue;
+
+ size = kve->kve_end - kve->kve_start;
+ if (info_verbose)
+ {
+ fprintf_filtered (gdb_stdout,
+ "Save segment, %ld bytes at %s (%c%c%c)\n",
+ (long) size,
+ paddress (target_gdbarch (), kve->kve_start),
+ kve->kve_protection & KVME_PROT_READ ? 'r' : '-',
+ kve->kve_protection & KVME_PROT_WRITE ? 'w' : '-',
+ kve->kve_protection & KVME_PROT_EXEC ? 'x' : '-');
+ }
+
+ /* Invoke the callback function to create the corefile segment.
+ Pass MODIFIED as true, we do not know the real modification state. */
+ func (kve->kve_start, size, kve->kve_protection & KVME_PROT_READ,
+ kve->kve_protection & KVME_PROT_WRITE,
+ kve->kve_protection & KVME_PROT_EXEC, 1, obfd);
+ }
+ return 0;
+}
+#else
static int
fbsd_read_mapping (FILE *mapfile, unsigned long *start, unsigned long *end,
char *protection)
calling FUNC for each memory region. OBFD is passed as the last
argument to FUNC. */
-int
-fbsd_find_memory_regions (int (*func) (CORE_ADDR, unsigned long,
- int, int, int, void *),
- void *obfd)
+static int
+fbsd_find_memory_regions (struct target_ops *self,
+ find_memory_region_ftype func, void *obfd)
{
pid_t pid = ptid_get_pid (inferior_ptid);
- char *mapfilename;
- FILE *mapfile;
unsigned long start, end, size;
char protection[4];
int read, write, exec;
- mapfilename = xstrprintf ("/proc/%ld/map", (long) pid);
- mapfile = fopen (mapfilename, "r");
+ std::string mapfilename = string_printf ("/proc/%ld/map", (long) pid);
+ gdb_file_up mapfile (fopen (mapfilename.c_str (), "r"));
if (mapfile == NULL)
- error (_("Couldn't open %s."), mapfilename);
+ error (_("Couldn't open %s."), mapfilename.c_str ());
if (info_verbose)
fprintf_filtered (gdb_stdout,
- "Reading memory regions from %s\n", mapfilename);
+ "Reading memory regions from %s\n", mapfilename.c_str ());
/* Now iterate until end-of-file. */
- while (fbsd_read_mapping (mapfile, &start, &end, &protection[0]))
+ while (fbsd_read_mapping (mapfile.get (), &start, &end, &protection[0]))
{
size = end - start;
if (info_verbose)
{
fprintf_filtered (gdb_stdout,
- "Save segment, %ld bytes at 0x%s (%c%c%c)\n",
- size, paddr_nz (start),
+ "Save segment, %ld bytes at %s (%c%c%c)\n",
+ size, paddress (target_gdbarch (), start),
read ? 'r' : '-',
write ? 'w' : '-',
exec ? 'x' : '-');
}
- /* Invoke the callback function to create the corefile segment. */
- func (start, size, read, write, exec, obfd);
+ /* Invoke the callback function to create the corefile segment.
+ Pass MODIFIED as true, we do not know the real modification state. */
+ func (start, size, read, write, exec, 1, obfd);
+ }
+
+ return 0;
+}
+#endif
+
+#ifdef KERN_PROC_AUXV
+static enum target_xfer_status (*super_xfer_partial) (struct target_ops *ops,
+ enum target_object object,
+ const char *annex,
+ gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset,
+ ULONGEST len,
+ ULONGEST *xfered_len);
+
+#ifdef PT_LWPINFO
+/* Return the size of siginfo for the current inferior. */
+
+#ifdef __LP64__
+union sigval32 {
+ int sival_int;
+ uint32_t sival_ptr;
+};
+
+/* This structure matches the naming and layout of `siginfo_t' in
+ <sys/signal.h>. In particular, the `si_foo' macros defined in that
+ header can be used with both types to copy fields in the `_reason'
+ union. */
+
+struct siginfo32
+{
+ int si_signo;
+ int si_errno;
+ int si_code;
+ __pid_t si_pid;
+ __uid_t si_uid;
+ int si_status;
+ uint32_t si_addr;
+ union sigval32 si_value;
+ union
+ {
+ struct
+ {
+ int _trapno;
+ } _fault;
+ struct
+ {
+ int _timerid;
+ int _overrun;
+ } _timer;
+ struct
+ {
+ int _mqd;
+ } _mesgq;
+ struct
+ {
+ int32_t _band;
+ } _poll;
+ struct
+ {
+ int32_t __spare1__;
+ int __spare2__[7];
+ } __spare__;
+ } _reason;
+};
+#endif
+
+static size_t
+fbsd_siginfo_size ()
+{
+#ifdef __LP64__
+ struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
+
+ /* Is the inferior 32-bit? If so, use the 32-bit siginfo size. */
+ if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word == 32)
+ return sizeof (struct siginfo32);
+#endif
+ return sizeof (siginfo_t);
+}
+
+/* Convert a native 64-bit siginfo object to a 32-bit object. Note
+ that FreeBSD doesn't support writing to $_siginfo, so this only
+ needs to convert one way. */
+
+static void
+fbsd_convert_siginfo (siginfo_t *si)
+{
+#ifdef __LP64__
+ struct gdbarch *gdbarch = get_frame_arch (get_current_frame ());
+
+ /* Is the inferior 32-bit? If not, nothing to do. */
+ if (gdbarch_bfd_arch_info (gdbarch)->bits_per_word != 32)
+ return;
+
+ struct siginfo32 si32;
+
+ si32.si_signo = si->si_signo;
+ si32.si_errno = si->si_errno;
+ si32.si_code = si->si_code;
+ si32.si_pid = si->si_pid;
+ si32.si_uid = si->si_uid;
+ si32.si_status = si->si_status;
+ si32.si_addr = (uintptr_t) si->si_addr;
+
+ /* If sival_ptr is being used instead of sival_int on a big-endian
+ platform, then sival_int will be zero since it holds the upper
+ 32-bits of the pointer value. */
+#if _BYTE_ORDER == _BIG_ENDIAN
+ if (si->si_value.sival_int == 0)
+ si32.si_value.sival_ptr = (uintptr_t) si->si_value.sival_ptr;
+ else
+ si32.si_value.sival_int = si->si_value.sival_int;
+#else
+ si32.si_value.sival_int = si->si_value.sival_int;
+#endif
+
+ /* Always copy the spare fields and then possibly overwrite them for
+ signal-specific or code-specific fields. */
+ si32._reason.__spare__.__spare1__ = si->_reason.__spare__.__spare1__;
+ for (int i = 0; i < 7; i++)
+ si32._reason.__spare__.__spare2__[i] = si->_reason.__spare__.__spare2__[i];
+ switch (si->si_signo) {
+ case SIGILL:
+ case SIGFPE:
+ case SIGSEGV:
+ case SIGBUS:
+ si32.si_trapno = si->si_trapno;
+ break;
+ }
+ switch (si->si_code) {
+ case SI_TIMER:
+ si32.si_timerid = si->si_timerid;
+ si32.si_overrun = si->si_overrun;
+ break;
+ case SI_MESGQ:
+ si32.si_mqd = si->si_mqd;
+ break;
+ }
+
+ memcpy(si, &si32, sizeof (si32));
+#endif
+}
+#endif
+
+/* Implement the "to_xfer_partial target_ops" method. */
+
+static enum target_xfer_status
+fbsd_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
+{
+ pid_t pid = ptid_get_pid (inferior_ptid);
+
+ switch (object)
+ {
+#ifdef PT_LWPINFO
+ case TARGET_OBJECT_SIGNAL_INFO:
+ {
+ struct ptrace_lwpinfo pl;
+ size_t siginfo_size;
+
+ /* FreeBSD doesn't support writing to $_siginfo. */
+ if (writebuf != NULL)
+ return TARGET_XFER_E_IO;
+
+ if (inferior_ptid.lwp_p ())
+ pid = inferior_ptid.lwp ();
+
+ siginfo_size = fbsd_siginfo_size ();
+ if (offset > siginfo_size)
+ return TARGET_XFER_E_IO;
+
+ if (ptrace (PT_LWPINFO, pid, (PTRACE_TYPE_ARG3) &pl, sizeof (pl)) == -1)
+ return TARGET_XFER_E_IO;
+
+ if (!(pl.pl_flags & PL_FLAG_SI))
+ return TARGET_XFER_E_IO;
+
+ fbsd_convert_siginfo (&pl.pl_siginfo);
+ if (offset + len > siginfo_size)
+ len = siginfo_size - offset;
+
+ memcpy (readbuf, ((gdb_byte *) &pl.pl_siginfo) + offset, len);
+ *xfered_len = len;
+ return TARGET_XFER_OK;
+ }
+#endif
+ case TARGET_OBJECT_AUXV:
+ {
+ gdb::byte_vector buf_storage;
+ gdb_byte *buf;
+ size_t buflen;
+ int mib[4];
+
+ if (writebuf != NULL)
+ return TARGET_XFER_E_IO;
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_PROC;
+ mib[2] = KERN_PROC_AUXV;
+ mib[3] = pid;
+ if (offset == 0)
+ {
+ buf = readbuf;
+ buflen = len;
+ }
+ else
+ {
+ buflen = offset + len;
+ buf_storage.resize (buflen);
+ buf = buf_storage.data ();
+ }
+ if (sysctl (mib, 4, buf, &buflen, NULL, 0) == 0)
+ {
+ if (offset != 0)
+ {
+ if (buflen > offset)
+ {
+ buflen -= offset;
+ memcpy (readbuf, buf + offset, buflen);
+ }
+ else
+ buflen = 0;
+ }
+ *xfered_len = buflen;
+ return (buflen == 0) ? TARGET_XFER_EOF : TARGET_XFER_OK;
+ }
+ return TARGET_XFER_E_IO;
+ }
+ default:
+ return super_xfer_partial (ops, object, annex, readbuf, writebuf, offset,
+ len, xfered_len);
}
+}
+#endif
+
+#ifdef PT_LWPINFO
+static int debug_fbsd_lwp;
+
+static void (*super_resume) (struct target_ops *,
+ ptid_t,
+ int,
+ enum gdb_signal);
+static ptid_t (*super_wait) (struct target_ops *,
+ ptid_t,
+ struct target_waitstatus *,
+ int);
+
+static void
+show_fbsd_lwp_debug (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("Debugging of FreeBSD lwp module is %s.\n"), value);
+}
+
+#if defined(TDP_RFPPWAIT) || defined(HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME)
+/* Fetch the external variant of the kernel's internal process
+ structure for the process PID into KP. */
+
+static void
+fbsd_fetch_kinfo_proc (pid_t pid, struct kinfo_proc *kp)
+{
+ size_t len;
+ int mib[4];
+
+ len = sizeof *kp;
+ mib[0] = CTL_KERN;
+ mib[1] = KERN_PROC;
+ mib[2] = KERN_PROC_PID;
+ mib[3] = pid;
+ if (sysctl (mib, 4, kp, &len, NULL, 0) == -1)
+ perror_with_name (("sysctl"));
+}
+#endif
+
+/*
+ FreeBSD's first thread support was via a "reentrant" version of libc
+ (libc_r) that first shipped in 2.2.7. This library multiplexed all
+ of the threads in a process onto a single kernel thread. This
+ library was supported via the bsd-uthread target.
+
+ FreeBSD 5.1 introduced two new threading libraries that made use of
+ multiple kernel threads. The first (libkse) scheduled M user
+ threads onto N (<= M) kernel threads (LWPs). The second (libthr)
+ bound each user thread to a dedicated kernel thread. libkse shipped
+ as the default threading library (libpthread).
+
+ FreeBSD 5.3 added a libthread_db to abstract the interface across
+ the various thread libraries (libc_r, libkse, and libthr).
+
+ FreeBSD 7.0 switched the default threading library from from libkse
+ to libpthread and removed libc_r.
+
+ FreeBSD 8.0 removed libkse and the in-kernel support for it. The
+ only threading library supported by 8.0 and later is libthr which
+ ties each user thread directly to an LWP. To simplify the
+ implementation, this target only supports LWP-backed threads using
+ ptrace directly rather than libthread_db.
+
+ FreeBSD 11.0 introduced LWP event reporting via PT_LWP_EVENTS.
+*/
+
+/* Return true if PTID is still active in the inferior. */
+
+static int
+fbsd_thread_alive (struct target_ops *ops, ptid_t ptid)
+{
+ if (ptid_lwp_p (ptid))
+ {
+ struct ptrace_lwpinfo pl;
+
+ if (ptrace (PT_LWPINFO, ptid_get_lwp (ptid), (caddr_t) &pl, sizeof pl)
+ == -1)
+ return 0;
+#ifdef PL_FLAG_EXITED
+ if (pl.pl_flags & PL_FLAG_EXITED)
+ return 0;
+#endif
+ }
+
+ return 1;
+}
+
+/* Convert PTID to a string. Returns the string in a static
+ buffer. */
+
+static const char *
+fbsd_pid_to_str (struct target_ops *ops, ptid_t ptid)
+{
+ lwpid_t lwp;
+
+ lwp = ptid_get_lwp (ptid);
+ if (lwp != 0)
+ {
+ static char buf[64];
+ int pid = ptid_get_pid (ptid);
+
+ xsnprintf (buf, sizeof buf, "LWP %d of process %d", lwp, pid);
+ return buf;
+ }
+
+ return normal_pid_to_str (ptid);
+}
+
+#ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME
+/* Return the name assigned to a thread by an application. Returns
+ the string in a static buffer. */
+
+static const char *
+fbsd_thread_name (struct target_ops *self, struct thread_info *thr)
+{
+ struct ptrace_lwpinfo pl;
+ struct kinfo_proc kp;
+ int pid = ptid_get_pid (thr->ptid);
+ long lwp = ptid_get_lwp (thr->ptid);
+ static char buf[sizeof pl.pl_tdname + 1];
+
+ /* Note that ptrace_lwpinfo returns the process command in pl_tdname
+ if a name has not been set explicitly. Return a NULL name in
+ that case. */
+ fbsd_fetch_kinfo_proc (pid, &kp);
+ if (ptrace (PT_LWPINFO, lwp, (caddr_t) &pl, sizeof pl) == -1)
+ perror_with_name (("ptrace"));
+ if (strcmp (kp.ki_comm, pl.pl_tdname) == 0)
+ return NULL;
+ xsnprintf (buf, sizeof buf, "%s", pl.pl_tdname);
+ return buf;
+}
+#endif
+
+/* Enable additional event reporting on new processes.
+
+ To catch fork events, PTRACE_FORK is set on every traced process
+ to enable stops on returns from fork or vfork. Note that both the
+ parent and child will always stop, even if system call stops are
+ not enabled.
+
+ To catch LWP events, PTRACE_EVENTS is set on every traced process.
+ This enables stops on the birth for new LWPs (excluding the "main" LWP)
+ and the death of LWPs (excluding the last LWP in a process). Note
+ that unlike fork events, the LWP that creates a new LWP does not
+ report an event. */
+
+static void
+fbsd_enable_proc_events (pid_t pid)
+{
+#ifdef PT_GET_EVENT_MASK
+ int events;
+
+ if (ptrace (PT_GET_EVENT_MASK, pid, (PTRACE_TYPE_ARG3)&events,
+ sizeof (events)) == -1)
+ perror_with_name (("ptrace"));
+ events |= PTRACE_FORK | PTRACE_LWP;
+#ifdef PTRACE_VFORK
+ events |= PTRACE_VFORK;
+#endif
+ if (ptrace (PT_SET_EVENT_MASK, pid, (PTRACE_TYPE_ARG3)&events,
+ sizeof (events)) == -1)
+ perror_with_name (("ptrace"));
+#else
+#ifdef TDP_RFPPWAIT
+ if (ptrace (PT_FOLLOW_FORK, pid, (PTRACE_TYPE_ARG3)0, 1) == -1)
+ perror_with_name (("ptrace"));
+#endif
+#ifdef PT_LWP_EVENTS
+ if (ptrace (PT_LWP_EVENTS, pid, (PTRACE_TYPE_ARG3)0, 1) == -1)
+ perror_with_name (("ptrace"));
+#endif
+#endif
+}
+
+/* Add threads for any new LWPs in a process.
+
+ When LWP events are used, this function is only used to detect existing
+ threads when attaching to a process. On older systems, this function is
+ called to discover new threads each time the thread list is updated. */
+
+static void
+fbsd_add_threads (pid_t pid)
+{
+ int i, nlwps;
+
+ gdb_assert (!in_thread_list (pid_to_ptid (pid)));
+ nlwps = ptrace (PT_GETNUMLWPS, pid, NULL, 0);
+ if (nlwps == -1)
+ perror_with_name (("ptrace"));
+
+ gdb::unique_xmalloc_ptr<lwpid_t[]> lwps (XCNEWVEC (lwpid_t, nlwps));
+
+ nlwps = ptrace (PT_GETLWPLIST, pid, (caddr_t) lwps.get (), nlwps);
+ if (nlwps == -1)
+ perror_with_name (("ptrace"));
+
+ for (i = 0; i < nlwps; i++)
+ {
+ ptid_t ptid = ptid_build (pid, lwps[i], 0);
+
+ if (!in_thread_list (ptid))
+ {
+#ifdef PT_LWP_EVENTS
+ struct ptrace_lwpinfo pl;
+
+ /* Don't add exited threads. Note that this is only called
+ when attaching to a multi-threaded process. */
+ if (ptrace (PT_LWPINFO, lwps[i], (caddr_t) &pl, sizeof pl) == -1)
+ perror_with_name (("ptrace"));
+ if (pl.pl_flags & PL_FLAG_EXITED)
+ continue;
+#endif
+ if (debug_fbsd_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "FLWP: adding thread for LWP %u\n",
+ lwps[i]);
+ add_thread (ptid);
+ }
+ }
+}
+
+/* Implement the "to_update_thread_list" target_ops method. */
+
+static void
+fbsd_update_thread_list (struct target_ops *ops)
+{
+#ifdef PT_LWP_EVENTS
+ /* With support for thread events, threads are added/deleted from the
+ list as events are reported, so just try deleting exited threads. */
+ delete_exited_threads ();
+#else
+ prune_threads ();
+
+ fbsd_add_threads (ptid_get_pid (inferior_ptid));
+#endif
+}
+
+#ifdef TDP_RFPPWAIT
+/*
+ To catch fork events, PT_FOLLOW_FORK is set on every traced process
+ to enable stops on returns from fork or vfork. Note that both the
+ parent and child will always stop, even if system call stops are not
+ enabled.
+
+ After a fork, both the child and parent process will stop and report
+ an event. However, there is no guarantee of order. If the parent
+ reports its stop first, then fbsd_wait explicitly waits for the new
+ child before returning. If the child reports its stop first, then
+ the event is saved on a list and ignored until the parent's stop is
+ reported. fbsd_wait could have been changed to fetch the parent PID
+ of the new child and used that to wait for the parent explicitly.
+ However, if two threads in the parent fork at the same time, then
+ the wait on the parent might return the "wrong" fork event.
+
+ The initial version of PT_FOLLOW_FORK did not set PL_FLAG_CHILD for
+ the new child process. This flag could be inferred by treating any
+ events for an unknown pid as a new child.
+
+ In addition, the initial version of PT_FOLLOW_FORK did not report a
+ stop event for the parent process of a vfork until after the child
+ process executed a new program or exited. The kernel was changed to
+ defer the wait for exit or exec of the child until after posting the
+ stop event shortly after the change to introduce PL_FLAG_CHILD.
+ This could be worked around by reporting a vfork event when the
+ child event posted and ignoring the subsequent event from the
+ parent.
+
+ This implementation requires both of these fixes for simplicity's
+ sake. FreeBSD versions newer than 9.1 contain both fixes.
+*/
+
+static std::list<ptid_t> fbsd_pending_children;
+
+/* Record a new child process event that is reported before the
+ corresponding fork event in the parent. */
+
+static void
+fbsd_remember_child (ptid_t pid)
+{
+ fbsd_pending_children.push_front (pid);
+}
+
+/* Check for a previously-recorded new child process event for PID.
+ If one is found, remove it from the list and return the PTID. */
+
+static ptid_t
+fbsd_is_child_pending (pid_t pid)
+{
+ for (auto it = fbsd_pending_children.begin ();
+ it != fbsd_pending_children.end (); it++)
+ if (it->pid () == pid)
+ {
+ ptid_t ptid = *it;
+ fbsd_pending_children.erase (it);
+ return ptid;
+ }
+ return null_ptid;
+}
+
+#ifndef PTRACE_VFORK
+static std::forward_list<ptid_t> fbsd_pending_vfork_done;
+
+/* Record a pending vfork done event. */
- fclose (mapfile);
+static void
+fbsd_add_vfork_done (ptid_t pid)
+{
+ fbsd_pending_vfork_done.push_front (pid);
+}
+
+/* Check for a pending vfork done event for a specific PID. */
+
+static int
+fbsd_is_vfork_done_pending (pid_t pid)
+{
+ for (auto it = fbsd_pending_vfork_done.begin ();
+ it != fbsd_pending_vfork_done.end (); it++)
+ if (it->pid () == pid)
+ return 1;
return 0;
}
-/* Create appropriate note sections for a corefile, returning them in
- allocated memory. */
+/* Check for a pending vfork done event. If one is found, remove it
+ from the list and return the PTID. */
+
+static ptid_t
+fbsd_next_vfork_done (void)
+{
+ if (!fbsd_pending_vfork_done.empty ())
+ {
+ ptid_t ptid = fbsd_pending_vfork_done.front ();
+ fbsd_pending_vfork_done.pop_front ();
+ return ptid;
+ }
+ return null_ptid;
+}
+#endif
+#endif
+
+/* Implement the "to_resume" target_ops method. */
+
+static void
+fbsd_resume (struct target_ops *ops,
+ ptid_t ptid, int step, enum gdb_signal signo)
+{
+#if defined(TDP_RFPPWAIT) && !defined(PTRACE_VFORK)
+ pid_t pid;
+
+ /* Don't PT_CONTINUE a process which has a pending vfork done event. */
+ if (ptid_equal (minus_one_ptid, ptid))
+ pid = ptid_get_pid (inferior_ptid);
+ else
+ pid = ptid_get_pid (ptid);
+ if (fbsd_is_vfork_done_pending (pid))
+ return;
+#endif
+
+ if (debug_fbsd_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "FLWP: fbsd_resume for ptid (%d, %ld, %ld)\n",
+ ptid_get_pid (ptid), ptid_get_lwp (ptid),
+ ptid_get_tid (ptid));
+ if (ptid_lwp_p (ptid))
+ {
+ /* If ptid is a specific LWP, suspend all other LWPs in the process. */
+ struct thread_info *tp;
+ int request;
+
+ ALL_NON_EXITED_THREADS (tp)
+ {
+ if (ptid_get_pid (tp->ptid) != ptid_get_pid (ptid))
+ continue;
+
+ if (ptid_get_lwp (tp->ptid) == ptid_get_lwp (ptid))
+ request = PT_RESUME;
+ else
+ request = PT_SUSPEND;
+
+ if (ptrace (request, ptid_get_lwp (tp->ptid), NULL, 0) == -1)
+ perror_with_name (("ptrace"));
+ }
+ }
+ else
+ {
+ /* If ptid is a wildcard, resume all matching threads (they won't run
+ until the process is continued however). */
+ struct thread_info *tp;
+
+ ALL_NON_EXITED_THREADS (tp)
+ {
+ if (!ptid_match (tp->ptid, ptid))
+ continue;
+
+ if (ptrace (PT_RESUME, ptid_get_lwp (tp->ptid), NULL, 0) == -1)
+ perror_with_name (("ptrace"));
+ }
+ ptid = inferior_ptid;
+ }
+ super_resume (ops, ptid, step, signo);
+}
+
+/* Wait for the child specified by PTID to do something. Return the
+ process ID of the child, or MINUS_ONE_PTID in case of error; store
+ the status in *OURSTATUS. */
-char *
-fbsd_make_corefile_notes (bfd *obfd, int *note_size)
+static ptid_t
+fbsd_wait (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus,
+ int target_options)
{
- struct gdbarch *gdbarch = current_gdbarch;
- const struct regcache *regcache = current_regcache;
- gregset_t gregs;
- fpregset_t fpregs;
- char *note_data = NULL;
- Elf_Internal_Ehdr *i_ehdrp;
- const struct regset *regset;
- size_t size;
+ ptid_t wptid;
+
+ while (1)
+ {
+#ifndef PTRACE_VFORK
+ wptid = fbsd_next_vfork_done ();
+ if (!ptid_equal (wptid, null_ptid))
+ {
+ ourstatus->kind = TARGET_WAITKIND_VFORK_DONE;
+ return wptid;
+ }
+#endif
+ wptid = super_wait (ops, ptid, ourstatus, target_options);
+ if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
+ {
+ struct ptrace_lwpinfo pl;
+ pid_t pid;
+ int status;
- /* Put a "FreeBSD" label in the ELF header. */
- i_ehdrp = elf_elfheader (obfd);
- i_ehdrp->e_ident[EI_OSABI] = ELFOSABI_FREEBSD;
+ pid = ptid_get_pid (wptid);
+ if (ptrace (PT_LWPINFO, pid, (caddr_t) &pl, sizeof pl) == -1)
+ perror_with_name (("ptrace"));
- gdb_assert (gdbarch_regset_from_core_section_p (gdbarch));
+ wptid = ptid_build (pid, pl.pl_lwpid, 0);
- size = sizeof gregs;
- regset = gdbarch_regset_from_core_section (gdbarch, ".reg", size);
- gdb_assert (regset && regset->collect_regset);
- regset->collect_regset (regset, regcache, -1, &gregs, size);
+#ifdef PT_LWP_EVENTS
+ if (pl.pl_flags & PL_FLAG_EXITED)
+ {
+ /* If GDB attaches to a multi-threaded process, exiting
+ threads might be skipped during fbsd_post_attach that
+ have not yet reported their PL_FLAG_EXITED event.
+ Ignore EXITED events for an unknown LWP. */
+ if (in_thread_list (wptid))
+ {
+ if (debug_fbsd_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "FLWP: deleting thread for LWP %u\n",
+ pl.pl_lwpid);
+ if (print_thread_events)
+ printf_unfiltered (_("[%s exited]\n"), target_pid_to_str
+ (wptid));
+ delete_thread (wptid);
+ }
+ if (ptrace (PT_CONTINUE, pid, (caddr_t) 1, 0) == -1)
+ perror_with_name (("ptrace"));
+ continue;
+ }
+#endif
+
+ /* Switch to an LWP PTID on the first stop in a new process.
+ This is done after handling PL_FLAG_EXITED to avoid
+ switching to an exited LWP. It is done before checking
+ PL_FLAG_BORN in case the first stop reported after
+ attaching to an existing process is a PL_FLAG_BORN
+ event. */
+ if (in_thread_list (pid_to_ptid (pid)))
+ {
+ if (debug_fbsd_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "FLWP: using LWP %u for first thread\n",
+ pl.pl_lwpid);
+ thread_change_ptid (pid_to_ptid (pid), wptid);
+ }
+
+#ifdef PT_LWP_EVENTS
+ if (pl.pl_flags & PL_FLAG_BORN)
+ {
+ /* If GDB attaches to a multi-threaded process, newborn
+ threads might be added by fbsd_add_threads that have
+ not yet reported their PL_FLAG_BORN event. Ignore
+ BORN events for an already-known LWP. */
+ if (!in_thread_list (wptid))
+ {
+ if (debug_fbsd_lwp)
+ fprintf_unfiltered (gdb_stdlog,
+ "FLWP: adding thread for LWP %u\n",
+ pl.pl_lwpid);
+ add_thread (wptid);
+ }
+ ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
+ return wptid;
+ }
+#endif
+
+#ifdef TDP_RFPPWAIT
+ if (pl.pl_flags & PL_FLAG_FORKED)
+ {
+#ifndef PTRACE_VFORK
+ struct kinfo_proc kp;
+#endif
+ ptid_t child_ptid;
+ pid_t child;
+
+ child = pl.pl_child_pid;
+ ourstatus->kind = TARGET_WAITKIND_FORKED;
+#ifdef PTRACE_VFORK
+ if (pl.pl_flags & PL_FLAG_VFORKED)
+ ourstatus->kind = TARGET_WAITKIND_VFORKED;
+#endif
+
+ /* Make sure the other end of the fork is stopped too. */
+ child_ptid = fbsd_is_child_pending (child);
+ if (ptid_equal (child_ptid, null_ptid))
+ {
+ pid = waitpid (child, &status, 0);
+ if (pid == -1)
+ perror_with_name (("waitpid"));
+
+ gdb_assert (pid == child);
+
+ if (ptrace (PT_LWPINFO, child, (caddr_t)&pl, sizeof pl) == -1)
+ perror_with_name (("ptrace"));
+
+ gdb_assert (pl.pl_flags & PL_FLAG_CHILD);
+ child_ptid = ptid_build (child, pl.pl_lwpid, 0);
+ }
+
+ /* Enable additional events on the child process. */
+ fbsd_enable_proc_events (ptid_get_pid (child_ptid));
+
+#ifndef PTRACE_VFORK
+ /* For vfork, the child process will have the P_PPWAIT
+ flag set. */
+ fbsd_fetch_kinfo_proc (child, &kp);
+ if (kp.ki_flag & P_PPWAIT)
+ ourstatus->kind = TARGET_WAITKIND_VFORKED;
+#endif
+ ourstatus->value.related_pid = child_ptid;
+
+ return wptid;
+ }
+
+ if (pl.pl_flags & PL_FLAG_CHILD)
+ {
+ /* Remember that this child forked, but do not report it
+ until the parent reports its corresponding fork
+ event. */
+ fbsd_remember_child (wptid);
+ continue;
+ }
+
+#ifdef PTRACE_VFORK
+ if (pl.pl_flags & PL_FLAG_VFORK_DONE)
+ {
+ ourstatus->kind = TARGET_WAITKIND_VFORK_DONE;
+ return wptid;
+ }
+#endif
+#endif
- note_data = elfcore_write_prstatus (obfd, note_data, note_size,
- ptid_get_pid (inferior_ptid),
- stop_signal, &gregs);
+#ifdef PL_FLAG_EXEC
+ if (pl.pl_flags & PL_FLAG_EXEC)
+ {
+ ourstatus->kind = TARGET_WAITKIND_EXECD;
+ ourstatus->value.execd_pathname
+ = xstrdup (fbsd_pid_to_exec_file (NULL, pid));
+ return wptid;
+ }
+#endif
- size = sizeof fpregs;
- regset = gdbarch_regset_from_core_section (gdbarch, ".reg2", size);
- gdb_assert (regset && regset->collect_regset);
- regset->collect_regset (regset, regcache, -1, &fpregs, size);
+ /* Note that PL_FLAG_SCE is set for any event reported while
+ a thread is executing a system call in the kernel. In
+ particular, signals that interrupt a sleep in a system
+ call will report this flag as part of their event. Stops
+ explicitly for system call entry and exit always use
+ SIGTRAP, so only treat SIGTRAP events as system call
+ entry/exit events. */
+ if (pl.pl_flags & (PL_FLAG_SCE | PL_FLAG_SCX)
+ && ourstatus->value.sig == SIGTRAP)
+ {
+#ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_SYSCALL_CODE
+ if (catch_syscall_enabled ())
+ {
+ if (catching_syscall_number (pl.pl_syscall_code))
+ {
+ if (pl.pl_flags & PL_FLAG_SCE)
+ ourstatus->kind = TARGET_WAITKIND_SYSCALL_ENTRY;
+ else
+ ourstatus->kind = TARGET_WAITKIND_SYSCALL_RETURN;
+ ourstatus->value.syscall_number = pl.pl_syscall_code;
+ return wptid;
+ }
+ }
+#endif
+ /* If the core isn't interested in this event, just
+ continue the process explicitly and wait for another
+ event. Note that PT_SYSCALL is "sticky" on FreeBSD
+ and once system call stops are enabled on a process
+ it stops for all system call entries and exits. */
+ if (ptrace (PT_CONTINUE, pid, (caddr_t) 1, 0) == -1)
+ perror_with_name (("ptrace"));
+ continue;
+ }
+ }
+ return wptid;
+ }
+}
- note_data = elfcore_write_prfpreg (obfd, note_data, note_size,
- &fpregs, sizeof (fpregs));
+#ifdef TDP_RFPPWAIT
+/* Target hook for follow_fork. On entry and at return inferior_ptid is
+ the ptid of the followed inferior. */
- if (get_exec_file (0))
+static int
+fbsd_follow_fork (struct target_ops *ops, int follow_child,
+ int detach_fork)
+{
+ if (!follow_child && detach_fork)
{
- char *fname = strrchr (get_exec_file (0), '/') + 1;
- char *psargs = xstrdup (fname);
+ struct thread_info *tp = inferior_thread ();
+ pid_t child_pid = ptid_get_pid (tp->pending_follow.value.related_pid);
+
+ /* Breakpoints have already been detached from the child by
+ infrun.c. */
+
+ if (ptrace (PT_DETACH, child_pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
+ perror_with_name (("ptrace"));
+
+#ifndef PTRACE_VFORK
+ if (tp->pending_follow.kind == TARGET_WAITKIND_VFORKED)
+ {
+ /* We can't insert breakpoints until the child process has
+ finished with the shared memory region. The parent
+ process doesn't wait for the child process to exit or
+ exec until after it has been resumed from the ptrace stop
+ to report the fork. Once it has been resumed it doesn't
+ stop again before returning to userland, so there is no
+ reliable way to wait on the parent.
+
+ We can't stay attached to the child to wait for an exec
+ or exit because it may invoke ptrace(PT_TRACE_ME)
+ (e.g. if the parent process is a debugger forking a new
+ child process).
+
+ In the end, the best we can do is to make sure it runs
+ for a little while. Hopefully it will be out of range of
+ any breakpoints we reinsert. Usually this is only the
+ single-step breakpoint at vfork's return point. */
- if (get_inferior_args ())
- psargs = reconcat (psargs, psargs, " ", get_inferior_args (), NULL);
+ usleep (10000);
- note_data = elfcore_write_prpsinfo (obfd, note_data, note_size,
- fname, psargs);
+ /* Schedule a fake VFORK_DONE event to report on the next
+ wait. */
+ fbsd_add_vfork_done (inferior_ptid);
+ }
+#endif
}
- make_cleanup (xfree, note_data);
- return note_data;
+ return 0;
+}
+
+static int
+fbsd_insert_fork_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+
+static int
+fbsd_remove_fork_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+
+static int
+fbsd_insert_vfork_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+
+static int
+fbsd_remove_vfork_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+#endif
+
+/* Implement the "to_post_startup_inferior" target_ops method. */
+
+static void
+fbsd_post_startup_inferior (struct target_ops *self, ptid_t pid)
+{
+ fbsd_enable_proc_events (ptid_get_pid (pid));
+}
+
+/* Implement the "to_post_attach" target_ops method. */
+
+static void
+fbsd_post_attach (struct target_ops *self, int pid)
+{
+ fbsd_enable_proc_events (pid);
+ fbsd_add_threads (pid);
+}
+
+#ifdef PL_FLAG_EXEC
+/* If the FreeBSD kernel supports PL_FLAG_EXEC, then traced processes
+ will always stop after exec. */
+
+static int
+fbsd_insert_exec_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+
+static int
+fbsd_remove_exec_catchpoint (struct target_ops *self, int pid)
+{
+ return 0;
+}
+#endif
+
+#ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_SYSCALL_CODE
+static int
+fbsd_set_syscall_catchpoint (struct target_ops *self, int pid, int needed,
+ int any_count, int table_size, int *table)
+{
+
+ /* Ignore the arguments. inf-ptrace.c will use PT_SYSCALL which
+ will catch all system call entries and exits. The system calls
+ are filtered by GDB rather than the kernel. */
+ return 0;
+}
+#endif
+#endif
+
+void
+fbsd_nat_add_target (struct target_ops *t)
+{
+ t->to_pid_to_exec_file = fbsd_pid_to_exec_file;
+ t->to_find_memory_regions = fbsd_find_memory_regions;
+#ifdef KERN_PROC_AUXV
+ super_xfer_partial = t->to_xfer_partial;
+ t->to_xfer_partial = fbsd_xfer_partial;
+#endif
+#ifdef PT_LWPINFO
+ t->to_thread_alive = fbsd_thread_alive;
+ t->to_pid_to_str = fbsd_pid_to_str;
+#ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_TDNAME
+ t->to_thread_name = fbsd_thread_name;
+#endif
+ t->to_update_thread_list = fbsd_update_thread_list;
+ t->to_has_thread_control = tc_schedlock;
+ super_resume = t->to_resume;
+ t->to_resume = fbsd_resume;
+ super_wait = t->to_wait;
+ t->to_wait = fbsd_wait;
+ t->to_post_startup_inferior = fbsd_post_startup_inferior;
+ t->to_post_attach = fbsd_post_attach;
+#ifdef TDP_RFPPWAIT
+ t->to_follow_fork = fbsd_follow_fork;
+ t->to_insert_fork_catchpoint = fbsd_insert_fork_catchpoint;
+ t->to_remove_fork_catchpoint = fbsd_remove_fork_catchpoint;
+ t->to_insert_vfork_catchpoint = fbsd_insert_vfork_catchpoint;
+ t->to_remove_vfork_catchpoint = fbsd_remove_vfork_catchpoint;
+#endif
+#ifdef PL_FLAG_EXEC
+ t->to_insert_exec_catchpoint = fbsd_insert_exec_catchpoint;
+ t->to_remove_exec_catchpoint = fbsd_remove_exec_catchpoint;
+#endif
+#ifdef HAVE_STRUCT_PTRACE_LWPINFO_PL_SYSCALL_CODE
+ t->to_set_syscall_catchpoint = fbsd_set_syscall_catchpoint;
+#endif
+#endif
+ add_target (t);
+}
+
+void
+_initialize_fbsd_nat (void)
+{
+#ifdef PT_LWPINFO
+ add_setshow_boolean_cmd ("fbsd-lwp", class_maintenance,
+ &debug_fbsd_lwp, _("\
+Set debugging of FreeBSD lwp module."), _("\
+Show debugging of FreeBSD lwp module."), _("\
+Enables printf debugging output."),
+ NULL,
+ &show_fbsd_lwp_debug,
+ &setdebuglist, &showdebuglist);
+#endif
}
projects / deliverable / binutils-gdb.git / blobdiff