/* Target-struct-independent code to start (run) and stop an inferior
process.
- Copyright (C) 1986-2015 Free Software Foundation, Inc.
+ Copyright (C) 1986-2016 Free Software Foundation, Inc.
This file is part of GDB.
#include "solist.h"
#include "event-loop.h"
#include "thread-fsm.h"
+#include "common/enum-flags.h"
/* Prototypes for local functions */
/* Bit flags indicating what the thread needs to step over. */
-enum step_over_what
+enum step_over_what_flag
{
/* Step over a breakpoint. */
STEP_OVER_BREAKPOINT = 1,
expression. */
STEP_OVER_WATCHPOINT = 2
};
+DEF_ENUM_FLAGS_TYPE (enum step_over_what_flag, step_over_what);
/* Info about an instruction that is being stepped over. */
return 0;
}
+/* Return true if thread represented by PTID is doing a displaced
+ step. */
+
+static int
+displaced_step_in_progress_thread (ptid_t ptid)
+{
+ struct displaced_step_inferior_state *displaced;
+
+ gdb_assert (!ptid_equal (ptid, null_ptid));
+
+ displaced = get_displaced_stepping_state (ptid_get_pid (ptid));
+
+ return (displaced != NULL && ptid_equal (displaced->step_ptid, ptid));
+}
+
/* Return true if process PID has a thread doing a displaced step. */
static int
struct thread_info *tp = find_thread_ptid (ptid);
struct regcache *regcache = get_thread_regcache (ptid);
struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ struct address_space *aspace = get_regcache_aspace (regcache);
CORE_ADDR original, copy;
ULONGEST len;
struct displaced_step_closure *closure;
copy = gdbarch_displaced_step_location (gdbarch);
len = gdbarch_max_insn_length (gdbarch);
+ if (breakpoint_in_range_p (aspace, copy, len))
+ {
+ /* There's a breakpoint set in the scratch pad location range
+ (which is usually around the entry point). We'd either
+ install it before resuming, which would overwrite/corrupt the
+ scratch pad, or if it was already inserted, this displaced
+ step would overwrite it. The latter is OK in the sense that
+ we already assume that no thread is going to execute the code
+ in the scratch pad range (after initial startup) anyway, but
+ the former is unacceptable. Simply punt and fallback to
+ stepping over this breakpoint in-line. */
+ if (debug_displaced)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "displaced: breakpoint set in scratch pad. "
+ "Stepping over breakpoint in-line instead.\n");
+ }
+
+ do_cleanups (old_cleanups);
+ return -1;
+ }
+
/* Save the original contents of the copy area. */
displaced->step_saved_copy = (gdb_byte *) xmalloc (len);
ignore_cleanups = make_cleanup (free_current_contents,
static void keep_going_pass_signal (struct execution_control_state *ecs);
static void prepare_to_wait (struct execution_control_state *ecs);
static int keep_going_stepped_thread (struct thread_info *tp);
-static int thread_still_needs_step_over (struct thread_info *tp);
-static void stop_all_threads (void);
+static step_over_what thread_still_needs_step_over (struct thread_info *tp);
/* Are there any pending step-over requests? If so, run all we can
now and return true. Otherwise, return false. */
{
struct execution_control_state ecss;
struct execution_control_state *ecs = &ecss;
- enum step_over_what step_what;
+ step_over_what step_what;
int must_be_in_line;
next = thread_step_over_chain_next (tp);
gdb_assert (!(thread_has_single_step_breakpoints_set (tp) && step));
/* Decide the set of threads to ask the target to resume. */
- if ((step || thread_has_single_step_breakpoints_set (tp))
- && tp->control.trap_expected)
+ if (tp->control.trap_expected)
{
/* We're allowing a thread to run past a breakpoint it has
- hit, by single-stepping the thread with the breakpoint
- removed. In which case, we need to single-step only this
- thread, and keep others stopped, as they can miss this
- breakpoint if allowed to run. */
+ hit, either by single-stepping the thread with the breakpoint
+ removed, or by displaced stepping, with the breakpoint inserted.
+ In the former case, we need to single-step only this thread,
+ and keep others stopped, as they can miss this breakpoint if
+ allowed to run. That's not really a problem for displaced
+ stepping, but, we still keep other threads stopped, in case
+ another thread is also stopped for a breakpoint waiting for
+ its turn in the displaced stepping queue. */
resume_ptid = inferior_ptid;
}
else
to make progress when resumed. Returns an bitwise or of enum
step_over_what bits, indicating what needs to be stepped over. */
-static int
+static step_over_what
thread_still_needs_step_over (struct thread_info *tp)
{
struct inferior *inf = find_inferior_ptid (tp->ptid);
- int what = 0;
+ step_over_what what = 0;
if (thread_still_needs_step_over_bp (tp))
what |= STEP_OVER_BREAKPOINT;
/* Set the cached copy of the last ptid/waitstatus. */
-static void
+void
set_last_target_status (ptid_t ptid, struct target_waitstatus status)
{
target_last_wait_ptid = ptid;
}
}
-/* Stop all threads. */
+/* A cleanup that disables thread create/exit events. */
static void
+disable_thread_events (void *arg)
+{
+ target_thread_events (0);
+}
+
+/* See infrun.h. */
+
+void
stop_all_threads (void)
{
/* We may need multiple passes to discover all threads. */
entry_ptid = inferior_ptid;
old_chain = make_cleanup (switch_to_thread_cleanup, &entry_ptid);
+ target_thread_events (1);
+ make_cleanup (disable_thread_events, NULL);
+
/* Request threads to stop, and then wait for the stops. Because
threads we already know about can spawn more threads while we're
trying to stop them, and we only learn about new threads when we
{
/* All resumed threads exited. */
}
- else if (ws.kind == TARGET_WAITKIND_EXITED
+ else if (ws.kind == TARGET_WAITKIND_THREAD_EXITED
+ || ws.kind == TARGET_WAITKIND_EXITED
|| ws.kind == TARGET_WAITKIND_SIGNALLED)
{
if (debug_infrun)
}
else
{
+ struct inferior *inf;
+
t = find_thread_ptid (event_ptid);
if (t == NULL)
t = add_thread (event_ptid);
t->resumed = 0;
t->control.may_range_step = 0;
+ /* This may be the first time we see the inferior report
+ a stop. */
+ inf = find_inferior_ptid (event_ptid);
+ if (inf->needs_setup)
+ {
+ switch_to_thread_no_regs (t);
+ setup_inferior (0);
+ }
+
if (ws.kind == TARGET_WAITKIND_STOPPED
&& ws.value.sig == GDB_SIGNAL_0)
{
fprintf_unfiltered (gdb_stdlog, "infrun: stop_all_threads done\n");
}
+/* Handle a TARGET_WAITKIND_NO_RESUMED event. */
+
+static int
+handle_no_resumed (struct execution_control_state *ecs)
+{
+ struct inferior *inf;
+ struct thread_info *thread;
+
+ if (target_can_async_p () && !sync_execution)
+ {
+ /* There were no unwaited-for children left in the target, but,
+ we're not synchronously waiting for events either. Just
+ ignore. */
+
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: TARGET_WAITKIND_NO_RESUMED " "(ignoring: bg)\n");
+ prepare_to_wait (ecs);
+ return 1;
+ }
+
+ /* Otherwise, if we were running a synchronous execution command, we
+ may need to cancel it and give the user back the terminal.
+
+ In non-stop mode, the target can't tell whether we've already
+ consumed previous stop events, so it can end up sending us a
+ no-resumed event like so:
+
+ #0 - thread 1 is left stopped
+
+ #1 - thread 2 is resumed and hits breakpoint
+ -> TARGET_WAITKIND_STOPPED
+
+ #2 - thread 3 is resumed and exits
+ this is the last resumed thread, so
+ -> TARGET_WAITKIND_NO_RESUMED
+
+ #3 - gdb processes stop for thread 2 and decides to re-resume
+ it.
+
+ #4 - gdb processes the TARGET_WAITKIND_NO_RESUMED event.
+ thread 2 is now resumed, so the event should be ignored.
+
+ IOW, if the stop for thread 2 doesn't end a foreground command,
+ then we need to ignore the following TARGET_WAITKIND_NO_RESUMED
+ event. But it could be that the event meant that thread 2 itself
+ (or whatever other thread was the last resumed thread) exited.
+
+ To address this we refresh the thread list and check whether we
+ have resumed threads _now_. In the example above, this removes
+ thread 3 from the thread list. If thread 2 was re-resumed, we
+ ignore this event. If we find no thread resumed, then we cancel
+ the synchronous command show "no unwaited-for " to the user. */
+ update_thread_list ();
+
+ ALL_NON_EXITED_THREADS (thread)
+ {
+ if (thread->executing
+ || thread->suspend.waitstatus_pending_p)
+ {
+ /* There were no unwaited-for children left in the target at
+ some point, but there are now. Just ignore. */
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: TARGET_WAITKIND_NO_RESUMED "
+ "(ignoring: found resumed)\n");
+ prepare_to_wait (ecs);
+ return 1;
+ }
+ }
+
+ /* Note however that we may find no resumed thread because the whole
+ process exited meanwhile (thus updating the thread list results
+ in an empty thread list). In this case we know we'll be getting
+ a process exit event shortly. */
+ ALL_INFERIORS (inf)
+ {
+ if (inf->pid == 0)
+ continue;
+
+ thread = any_live_thread_of_process (inf->pid);
+ if (thread == NULL)
+ {
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog,
+ "infrun: TARGET_WAITKIND_NO_RESUMED "
+ "(expect process exit)\n");
+ prepare_to_wait (ecs);
+ return 1;
+ }
+ }
+
+ /* Go ahead and report the event. */
+ return 0;
+}
+
/* Given an execution control state that has been freshly filled in by
an event from the inferior, figure out what it means and take
appropriate action.
return;
}
- if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
- && target_can_async_p () && !sync_execution)
+ if (ecs->ws.kind == TARGET_WAITKIND_THREAD_EXITED)
{
- /* There were no unwaited-for children left in the target, but,
- we're not synchronously waiting for events either. Just
- ignore. Otherwise, if we were running a synchronous
- execution command, we need to cancel it and give the user
- back the terminal. */
if (debug_infrun)
- fprintf_unfiltered (gdb_stdlog,
- "infrun: TARGET_WAITKIND_NO_RESUMED (ignoring)\n");
+ fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_EXITED\n");
prepare_to_wait (ecs);
return;
}
+ if (ecs->ws.kind == TARGET_WAITKIND_NO_RESUMED
+ && handle_no_resumed (ecs))
+ return;
+
/* Cache the last pid/waitstatus. */
set_last_target_status (ecs->ptid, ecs->ws);
prepare_to_wait (ecs);
return;
+ case TARGET_WAITKIND_THREAD_CREATED:
+ if (debug_infrun)
+ fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_THREAD_CREATED\n");
+ if (!ptid_equal (ecs->ptid, inferior_ptid))
+ context_switch (ecs->ptid);
+ if (!switch_back_to_stepped_thread (ecs))
+ keep_going (ecs);
+ return;
+
case TARGET_WAITKIND_EXITED:
case TARGET_WAITKIND_SIGNALLED:
if (debug_infrun)
{
struct regcache *regcache = get_thread_regcache (ecs->ptid);
struct gdbarch *gdbarch = get_regcache_arch (regcache);
- struct displaced_step_inferior_state *displaced
- = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
/* If checking displaced stepping is supported, and thread
ecs->ptid is displaced stepping. */
- if (displaced && ptid_equal (displaced->step_ptid, ecs->ptid))
+ if (displaced_step_in_progress_thread (ecs->ptid))
{
struct inferior *parent_inf
= find_inferior_ptid (ecs->ptid);
if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
{
+ struct displaced_step_inferior_state *displaced
+ = get_displaced_stepping_state (ptid_get_pid (ecs->ptid));
+
/* Restore scratch pad for child process. */
displaced_step_restore (displaced, ecs->ws.value.related_pid);
}
context_switch (ecs->ptid);
if (deprecated_context_hook)
- deprecated_context_hook (pid_to_thread_id (ecs->ptid));
+ deprecated_context_hook (ptid_to_global_thread_id (ecs->ptid));
}
/* At this point, get hold of the now-current thread's frame. */
/* set_momentary_breakpoint_at_pc invalidates FRAME. */
frame = NULL;
- bp->thread = tp->num;
+ bp->thread = tp->global_num;
inferior_thread ()->control.exception_resume_breakpoint = bp;
}
}
bp = set_momentary_breakpoint_at_pc (get_frame_arch (frame),
handler, bp_exception_resume);
- bp->thread = tp->num;
+ bp->thread = tp->global_num;
inferior_thread ()->control.exception_resume_breakpoint = bp;
}
struct regcache *regcache = get_current_regcache ();
int remove_bp;
int remove_wps;
- enum step_over_what step_what;
+ step_over_what step_what;
/* Either the trap was not expected, but we are continuing
anyway (if we got a signal, the user asked it be passed to
void
print_signal_received_reason (struct ui_out *uiout, enum gdb_signal siggnal)
{
+ struct thread_info *thr = inferior_thread ();
+
annotate_signal ();
- if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
+ if (ui_out_is_mi_like_p (uiout))
+ ;
+ else if (show_thread_that_caused_stop ())
{
- struct thread_info *t = inferior_thread ();
+ const char *name;
+
+ ui_out_text (uiout, "\nThread ");
+ ui_out_field_fmt (uiout, "thread-id", "%s", print_thread_id (thr));
- ui_out_text (uiout, "\n[");
- ui_out_field_string (uiout, "thread-name",
- target_pid_to_str (t->ptid));
- ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
- ui_out_text (uiout, " stopped");
+ name = thr->name != NULL ? thr->name : target_thread_name (thr);
+ if (name != NULL)
+ {
+ ui_out_text (uiout, " \"");
+ ui_out_field_fmt (uiout, "name", "%s", name);
+ ui_out_text (uiout, "\"");
+ }
}
+ else
+ ui_out_text (uiout, "\nProgram");
+
+ if (siggnal == GDB_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
+ ui_out_text (uiout, " stopped");
else
{
- ui_out_text (uiout, "\nProgram received signal ");
+ ui_out_text (uiout, " received signal ");
annotate_signal_name ();
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string
"to change these tables.\n"));
}
-/* Check if it makes sense to read $_siginfo from the current thread
- at this point. If not, throw an error. */
-
-static void
-validate_siginfo_access (void)
-{
- /* No current inferior, no siginfo. */
- if (ptid_equal (inferior_ptid, null_ptid))
- error (_("No thread selected."));
-
- /* Don't try to read from a dead thread. */
- if (is_exited (inferior_ptid))
- error (_("The current thread has terminated"));
-
- /* ... or from a spinning thread. */
- if (is_running (inferior_ptid))
- error (_("Selected thread is running."));
-}
-
/* The $_siginfo convenience variable is a bit special. We don't know
for sure the type of the value until we actually have a chance to
fetch the data. The type can change depending on gdbarch, so it is
{
LONGEST transferred;
- validate_siginfo_access ();
+ /* If we can access registers, so can we access $_siginfo. Likewise
+ vice versa. */
+ validate_registers_access ();
transferred =
target_read (¤t_target, TARGET_OBJECT_SIGNAL_INFO,
{
LONGEST transferred;
- validate_siginfo_access ();
+ /* If we can access registers, so can we access $_siginfo. Likewise
+ vice versa. */
+ validate_registers_access ();
transferred = target_write (¤t_target,
TARGET_OBJECT_SIGNAL_INFO,