#include "target.h"
#include "nat/linux-nat.h"
#include "nat/linux-waitpid.h"
-#include <string.h>
#include "gdb_wait.h"
-#include "gdb_assert.h"
#ifdef HAVE_TKILL_SYSCALL
#include <unistd.h>
#include <sys/syscall.h>
#endif
#include <sys/ptrace.h>
#include "linux-nat.h"
-#include "linux-ptrace.h"
-#include "linux-procfs.h"
+#include "nat/linux-ptrace.h"
+#include "nat/linux-procfs.h"
#include "linux-fork.h"
#include "gdbthread.h"
#include "gdbcmd.h"
#include <sys/types.h>
#include <dirent.h>
#include "xml-support.h"
-#include "terminal.h"
#include <sys/vfs.h>
#include "solib.h"
-#include "linux-osdata.h"
+#include "nat/linux-osdata.h"
#include "linux-tdep.h"
#include "symfile.h"
#include "agent.h"
#include "tracepoint.h"
-#include "exceptions.h"
#include "buffer.h"
#include "target-descriptions.h"
#include "filestuff.h"
delete_lwp (lp->ptid);
}
+/* Target hook for follow_fork. On entry inferior_ptid must be the
+ ptid of the followed inferior. At return, inferior_ptid will be
+ unchanged. */
+
static int
linux_child_follow_fork (struct target_ops *ops, int follow_child,
int detach_fork)
{
- int has_vforked;
- int parent_pid, child_pid;
-
- has_vforked = (inferior_thread ()->pending_follow.kind
- == TARGET_WAITKIND_VFORKED);
- parent_pid = ptid_get_lwp (inferior_ptid);
- if (parent_pid == 0)
- parent_pid = ptid_get_pid (inferior_ptid);
- child_pid
- = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid);
-
- if (has_vforked
- && !non_stop /* Non-stop always resumes both branches. */
- && (!target_is_async_p () || sync_execution)
- && !(follow_child || detach_fork || sched_multi))
- {
- /* The parent stays blocked inside the vfork syscall until the
- child execs or exits. If we don't let the child run, then
- the parent stays blocked. If we're telling the parent to run
- in the foreground, the user will not be able to ctrl-c to get
- back the terminal, effectively hanging the debug session. */
- fprintf_filtered (gdb_stderr, _("\
-Can not resume the parent process over vfork in the foreground while\n\
-holding the child stopped. Try \"set detach-on-fork\" or \
-\"set schedule-multiple\".\n"));
- /* FIXME output string > 80 columns. */
- return 1;
- }
-
- if (! follow_child)
+ if (!follow_child)
{
struct lwp_info *child_lp = NULL;
+ int status = W_STOPCODE (0);
+ struct cleanup *old_chain;
+ int has_vforked;
+ int parent_pid, child_pid;
+
+ has_vforked = (inferior_thread ()->pending_follow.kind
+ == TARGET_WAITKIND_VFORKED);
+ parent_pid = ptid_get_lwp (inferior_ptid);
+ if (parent_pid == 0)
+ parent_pid = ptid_get_pid (inferior_ptid);
+ child_pid
+ = ptid_get_pid (inferior_thread ()->pending_follow.value.related_pid);
+
/* We're already attached to the parent, by default. */
+ old_chain = save_inferior_ptid ();
+ inferior_ptid = ptid_build (child_pid, child_pid, 0);
+ child_lp = add_lwp (inferior_ptid);
+ child_lp->stopped = 1;
+ child_lp->last_resume_kind = resume_stop;
/* Detach new forked process? */
if (detach_fork)
{
- struct cleanup *old_chain;
-
- /* Before detaching from the child, remove all breakpoints
- from it. If we forked, then this has already been taken
- care of by infrun.c. If we vforked however, any
- breakpoint inserted in the parent is visible in the
- child, even those added while stopped in a vfork
- catchpoint. This will remove the breakpoints from the
- parent also, but they'll be reinserted below. */
- if (has_vforked)
- {
- /* keep breakpoints list in sync. */
- remove_breakpoints_pid (ptid_get_pid (inferior_ptid));
- }
-
- if (info_verbose || debug_linux_nat)
- {
- target_terminal_ours ();
- fprintf_filtered (gdb_stdlog,
- "Detaching after fork from "
- "child process %d.\n",
- child_pid);
- }
-
- old_chain = save_inferior_ptid ();
- inferior_ptid = ptid_build (child_pid, child_pid, 0);
-
- child_lp = add_lwp (inferior_ptid);
- child_lp->stopped = 1;
- child_lp->last_resume_kind = resume_stop;
make_cleanup (delete_lwp_cleanup, child_lp);
if (linux_nat_prepare_to_resume != NULL)
linux_nat_prepare_to_resume (child_lp);
- ptrace (PTRACE_DETACH, child_pid, 0, 0);
- do_cleanups (old_chain);
- }
- else
- {
- struct inferior *parent_inf, *child_inf;
- struct cleanup *old_chain;
-
- /* Add process to GDB's tables. */
- child_inf = add_inferior (child_pid);
-
- parent_inf = current_inferior ();
- child_inf->attach_flag = parent_inf->attach_flag;
- copy_terminal_info (child_inf, parent_inf);
- child_inf->gdbarch = parent_inf->gdbarch;
- copy_inferior_target_desc_info (child_inf, parent_inf);
-
- old_chain = save_inferior_ptid ();
- save_current_program_space ();
-
- inferior_ptid = ptid_build (child_pid, child_pid, 0);
- add_thread (inferior_ptid);
- child_lp = add_lwp (inferior_ptid);
- child_lp->stopped = 1;
- child_lp->last_resume_kind = resume_stop;
- child_inf->symfile_flags = SYMFILE_NO_READ;
-
- /* If this is a vfork child, then the address-space is
- shared with the parent. */
- if (has_vforked)
+ /* When debugging an inferior in an architecture that supports
+ hardware single stepping on a kernel without commit
+ 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child
+ process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits
+ set if the parent process had them set.
+ To work around this, single step the child process
+ once before detaching to clear the flags. */
+
+ if (!gdbarch_software_single_step_p (target_thread_architecture
+ (child_lp->ptid)))
{
- child_inf->pspace = parent_inf->pspace;
- child_inf->aspace = parent_inf->aspace;
-
- /* The parent will be frozen until the child is done
- with the shared region. Keep track of the
- parent. */
- child_inf->vfork_parent = parent_inf;
- child_inf->pending_detach = 0;
- parent_inf->vfork_child = child_inf;
- parent_inf->pending_detach = 0;
+ linux_disable_event_reporting (child_pid);
+ if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0)
+ perror_with_name (_("Couldn't do single step"));
+ if (my_waitpid (child_pid, &status, 0) < 0)
+ perror_with_name (_("Couldn't wait vfork process"));
}
- else
+
+ if (WIFSTOPPED (status))
{
- child_inf->aspace = new_address_space ();
- child_inf->pspace = add_program_space (child_inf->aspace);
- child_inf->removable = 1;
- set_current_program_space (child_inf->pspace);
- clone_program_space (child_inf->pspace, parent_inf->pspace);
-
- /* Let the shared library layer (solib-svr4) learn about
- this new process, relocate the cloned exec, pull in
- shared libraries, and install the solib event
- breakpoint. If a "cloned-VM" event was propagated
- better throughout the core, this wouldn't be
- required. */
- solib_create_inferior_hook (0);
+ int signo;
+
+ signo = WSTOPSIG (status);
+ if (signo != 0
+ && !signal_pass_state (gdb_signal_from_host (signo)))
+ signo = 0;
+ ptrace (PTRACE_DETACH, child_pid, 0, signo);
}
+ /* Resets value of inferior_ptid to parent ptid. */
+ do_cleanups (old_chain);
+ }
+ else
+ {
/* Let the thread_db layer learn about this new process. */
check_for_thread_db ();
-
- do_cleanups (old_chain);
}
+ do_cleanups (old_chain);
+
if (has_vforked)
{
struct lwp_info *parent_lp;
- struct inferior *parent_inf;
-
- parent_inf = current_inferior ();
-
- /* If we detached from the child, then we have to be careful
- to not insert breakpoints in the parent until the child
- is done with the shared memory region. However, if we're
- staying attached to the child, then we can and should
- insert breakpoints, so that we can debug it. A
- subsequent child exec or exit is enough to know when does
- the child stops using the parent's address space. */
- parent_inf->waiting_for_vfork_done = detach_fork;
- parent_inf->pspace->breakpoints_not_allowed = detach_fork;
parent_lp = find_lwp_pid (pid_to_ptid (parent_pid));
gdb_assert (linux_supports_tracefork () >= 0);
}
else
{
- struct inferior *parent_inf, *child_inf;
struct lwp_info *child_lp;
- struct program_space *parent_pspace;
- if (info_verbose || debug_linux_nat)
- {
- target_terminal_ours ();
- if (has_vforked)
- fprintf_filtered (gdb_stdlog,
- _("Attaching after process %d "
- "vfork to child process %d.\n"),
- parent_pid, child_pid);
- else
- fprintf_filtered (gdb_stdlog,
- _("Attaching after process %d "
- "fork to child process %d.\n"),
- parent_pid, child_pid);
- }
-
- /* Add the new inferior first, so that the target_detach below
- doesn't unpush the target. */
-
- child_inf = add_inferior (child_pid);
-
- parent_inf = current_inferior ();
- child_inf->attach_flag = parent_inf->attach_flag;
- copy_terminal_info (child_inf, parent_inf);
- child_inf->gdbarch = parent_inf->gdbarch;
- copy_inferior_target_desc_info (child_inf, parent_inf);
-
- parent_pspace = parent_inf->pspace;
-
- /* If we're vforking, we want to hold on to the parent until the
- child exits or execs. At child exec or exit time we can
- remove the old breakpoints from the parent and detach or
- resume debugging it. Otherwise, detach the parent now; we'll
- want to reuse it's program/address spaces, but we can't set
- them to the child before removing breakpoints from the
- parent, otherwise, the breakpoints module could decide to
- remove breakpoints from the wrong process (since they'd be
- assigned to the same address space). */
-
- if (has_vforked)
- {
- gdb_assert (child_inf->vfork_parent == NULL);
- gdb_assert (parent_inf->vfork_child == NULL);
- child_inf->vfork_parent = parent_inf;
- child_inf->pending_detach = 0;
- parent_inf->vfork_child = child_inf;
- parent_inf->pending_detach = detach_fork;
- parent_inf->waiting_for_vfork_done = 0;
- }
- else if (detach_fork)
- target_detach (NULL, 0);
-
- /* Note that the detach above makes PARENT_INF dangling. */
-
- /* Add the child thread to the appropriate lists, and switch to
- this new thread, before cloning the program space, and
- informing the solib layer about this new process. */
-
- inferior_ptid = ptid_build (child_pid, child_pid, 0);
- add_thread (inferior_ptid);
child_lp = add_lwp (inferior_ptid);
child_lp->stopped = 1;
child_lp->last_resume_kind = resume_stop;
- /* If this is a vfork child, then the address-space is shared
- with the parent. If we detached from the parent, then we can
- reuse the parent's program/address spaces. */
- if (has_vforked || detach_fork)
- {
- child_inf->pspace = parent_pspace;
- child_inf->aspace = child_inf->pspace->aspace;
- }
- else
- {
- child_inf->aspace = new_address_space ();
- child_inf->pspace = add_program_space (child_inf->aspace);
- child_inf->removable = 1;
- child_inf->symfile_flags = SYMFILE_NO_READ;
- set_current_program_space (child_inf->pspace);
- clone_program_space (child_inf->pspace, parent_pspace);
-
- /* Let the shared library layer (solib-svr4) learn about
- this new process, relocate the cloned exec, pull in
- shared libraries, and install the solib event breakpoint.
- If a "cloned-VM" event was propagated better throughout
- the core, this wouldn't be required. */
- solib_create_inferior_hook (0);
- }
-
/* Let the thread_db layer learn about this new process. */
check_for_thread_db ();
}
thread = find_thread_ptid (lp->ptid);
if (thread != NULL)
{
- if (signal_pass_state (thread->suspend.stop_signal))
- signo = thread->suspend.stop_signal;
+ signo = thread->suspend.stop_signal;
thread->suspend.stop_signal = GDB_SIGNAL_0;
}
}
{
int pid = ptid_get_lwp (lp->ptid);
struct target_waitstatus *ourstatus = &lp->waitstatus;
- int event = status >> 16;
+ int event = linux_ptrace_get_extended_event (status);
if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
|| event == PTRACE_EVENT_CLONE)
again before it gets to sigsuspend so we can safely let the handlers
get executed here. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "WL: about to sigsuspend\n");
sigsuspend (&suspend_mask);
}
}
/* Handle GNU/Linux's extended waitstatus for trace events. */
- if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP
+ && linux_is_extended_waitstatus (status))
{
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
linux_nat_filter_event (int lwpid, int status, int *new_pending_p)
{
struct lwp_info *lp;
+ int event = linux_ptrace_get_extended_event (status);
*new_pending_p = 0;
thread changes its tid to the tgid. */
if (WIFSTOPPED (status) && lp == NULL
- && (WSTOPSIG (status) == SIGTRAP && status >> 16 == PTRACE_EVENT_EXEC))
+ && (WSTOPSIG (status) == SIGTRAP && event == PTRACE_EVENT_EXEC))
{
/* A multi-thread exec after we had seen the leader exiting. */
if (debug_linux_nat)
}
/* Handle GNU/Linux's extended waitstatus for trace events. */
- if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP
+ && linux_is_extended_waitstatus (status))
{
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
gdb_assert (lp->resumed);
if (debug_linux_nat)
- fprintf (stderr,
- "LWP %ld got an event %06x, leaving pending.\n",
- ptid_get_lwp (lp->ptid), lp->status);
+ fprintf_unfiltered (gdb_stdlog,
+ "LWP %ld got an event %06x, "
+ "leaving pending.\n",
+ ptid_get_lwp (lp->ptid), lp->status);
if (WIFSTOPPED (lp->status))
{
lp->status = 0;
if (debug_linux_nat)
- fprintf (stderr,
- "LLW: LWP %ld hit a breakpoint while"
- " waiting for another process;"
- " cancelled it\n",
- ptid_get_lwp (lp->ptid));
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: LWP %ld hit a "
+ "breakpoint while "
+ "waiting for another "
+ "process; "
+ "cancelled it\n",
+ ptid_get_lwp (lp->ptid));
}
}
else
else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status))
{
if (debug_linux_nat)
- fprintf (stderr,
- "Process %ld exited while stopping LWPs\n",
- ptid_get_lwp (lp->ptid));
+ fprintf_unfiltered (gdb_stdlog,
+ "Process %ld exited while stopping "
+ "LWPs\n",
+ ptid_get_lwp (lp->ptid));
/* This was the last lwp in the process. Since
events are serialized to GDB core, and we can't
gdb_assert (lp == NULL);
/* Block until we get an event reported with SIGCHLD. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LNW: about to sigsuspend\n");
sigsuspend (&suspend_mask);
}
/* PTRACE_KILL may resume the inferior. Send SIGKILL first. */
errno = 0;
- kill (ptid_get_lwp (lp->ptid), SIGKILL);
+ kill_lwp (ptid_get_lwp (lp->ptid), SIGKILL);
if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
- target_pid_to_str (lp->ptid),
- errno ? safe_strerror (errno) : "OK");
+ {
+ int save_errno = errno;
+
+ fprintf_unfiltered (gdb_stdlog,
+ "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ save_errno ? safe_strerror (save_errno) : "OK");
+ }
/* Some kernels ignore even SIGKILL for processes under ptrace. */
errno = 0;
ptrace (PTRACE_KILL, ptid_get_lwp (lp->ptid), 0, 0);
if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
- target_pid_to_str (lp->ptid),
- errno ? safe_strerror (errno) : "OK");
+ {
+ int save_errno = errno;
+
+ fprintf_unfiltered (gdb_stdlog,
+ "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ save_errno ? safe_strerror (save_errno) : "OK");
+ }
return 0;
}
return buf;
}
-/* Records the thread's register state for the corefile note
- section. */
-
-static char *
-linux_nat_collect_thread_registers (const struct regcache *regcache,
- ptid_t ptid, bfd *obfd,
- char *note_data, int *note_size,
- enum gdb_signal stop_signal)
-{
- struct gdbarch *gdbarch = get_regcache_arch (regcache);
- const struct regset *regset;
- int core_regset_p;
- gdb_gregset_t gregs;
- gdb_fpregset_t fpregs;
-
- core_regset_p = gdbarch_regset_from_core_section_p (gdbarch);
-
- if (core_regset_p
- && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg",
- sizeof (gregs)))
- != NULL && regset->collect_regset != NULL)
- regset->collect_regset (regset, regcache, -1, &gregs, sizeof (gregs));
- else
- fill_gregset (regcache, &gregs, -1);
-
- note_data = (char *) elfcore_write_prstatus
- (obfd, note_data, note_size, ptid_get_lwp (ptid),
- gdb_signal_to_host (stop_signal), &gregs);
-
- if (core_regset_p
- && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2",
- sizeof (fpregs)))
- != NULL && regset->collect_regset != NULL)
- regset->collect_regset (regset, regcache, -1, &fpregs, sizeof (fpregs));
- else
- fill_fpregset (regcache, &fpregs, -1);
-
- note_data = (char *) elfcore_write_prfpreg (obfd, note_data, note_size,
- &fpregs, sizeof (fpregs));
-
- return note_data;
-}
-
-/* Fills the "to_make_corefile_note" target vector. Builds the note
- section for a corefile, and returns it in a malloc buffer. */
-
-static char *
-linux_nat_make_corefile_notes (struct target_ops *self,
- bfd *obfd, int *note_size)
-{
- /* FIXME: uweigand/2011-10-06: Once all GNU/Linux architectures have been
- converted to gdbarch_core_regset_sections, this function can go away. */
- return linux_make_corefile_notes (target_gdbarch (), obfd, note_size,
- linux_nat_collect_thread_registers);
-}
-
/* Implement the to_xfer_partial interface for memory reads using the /proc
filesystem. Because we can use a single read() call for /proc, this
can be much more efficient than banging away at PTRACE_PEEKTEXT,
t->to_post_startup_inferior = linux_child_post_startup_inferior;
t->to_post_attach = linux_child_post_attach;
t->to_follow_fork = linux_child_follow_fork;
- t->to_make_corefile_notes = linux_nat_make_corefile_notes;
super_xfer_partial = t->to_xfer_partial;
t->to_xfer_partial = linux_xfer_partial;
static int async_terminal_is_ours = 1;
-/* target_terminal_inferior implementation. */
+/* target_terminal_inferior implementation.
+
+ This is a wrapper around child_terminal_inferior to add async support. */
static void
linux_nat_terminal_inferior (struct target_ops *self)
set_sigint_trap ();
}
-/* target_terminal_ours implementation. */
+/* target_terminal_ours implementation.
+
+ This is a wrapper around child_terminal_ours to add async support (and
+ implement the target_terminal_ours vs target_terminal_ours_for_output
+ distinction). child_terminal_ours is currently no different than
+ child_terminal_ours_for_output.
+ We leave target_terminal_ours_for_output alone, leaving it to
+ child_terminal_ours_for_output. */
static void
linux_nat_terminal_ours (struct target_ops *self)
linux_nat_close (struct target_ops *self)
{
/* Unregister from the event loop. */
- if (linux_nat_is_async_p (NULL))
- linux_nat_async (NULL, NULL, 0);
+ if (linux_nat_is_async_p (self))
+ linux_nat_async (self, NULL, NULL);
if (linux_ops->to_close)
linux_ops->to_close (linux_ops);
struct inferior *inf;
int pid;
- pid = ptid_get_lwp (ptid);
if (ptid_get_lwp (ptid) == 0)
{
/* An (lwpid,0,0) ptid. Look up the lwp object to get at the
sigdelset (&suspend_mask, SIGCHLD);
sigemptyset (&blocked_mask);
+
+ /* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to
+ support read-only process state. */
+ linux_ptrace_set_additional_flags (PTRACE_O_TRACESYSGOOD
+ | PTRACE_O_TRACEVFORKDONE
+ | PTRACE_O_TRACEVFORK
+ | PTRACE_O_TRACEFORK
+ | PTRACE_O_TRACEEXEC);
}
\f