process.
Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994,
- 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002 Free Software
+ 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software
Foundation, Inc.
This file is part of GDB.
static void build_infrun (void);
-static void follow_inferior_fork (int parent_pid, int child_pid,
- int has_forked, int has_vforked);
-
-static void follow_fork (int parent_pid, int child_pid);
-
-static void follow_vfork (int parent_pid, int child_pid);
+static int follow_fork (void);
static void set_schedlock_func (char *args, int from_tty,
struct cmd_list_element *c);
struct
{
int parent_pid;
- int saw_parent_fork;
int child_pid;
- int saw_child_fork;
- int saw_child_exec;
}
fork_event;
char *execd_pathname;
static const char *follow_fork_mode_string = follow_fork_mode_parent;
\f
-static void
-follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
- int has_vforked)
+static int
+follow_fork (void)
{
- int followed_parent = 0;
- int followed_child = 0;
-
- /* Which process did the user want us to follow? */
const char *follow_mode = follow_fork_mode_string;
+ int follow_child = (follow_mode == follow_fork_mode_child);
/* Or, did the user not know, and want us to ask? */
if (follow_fork_mode_string == follow_fork_mode_ask)
/* follow_mode = follow_fork_mode_...; */
}
- /* If we're to be following the parent, then detach from child_pid.
- We're already following the parent, so need do nothing explicit
- for it. */
- if (follow_mode == follow_fork_mode_parent)
- {
- followed_parent = 1;
-
- /* We're already attached to the parent, by default. */
-
- /* Before detaching from the child, remove all breakpoints from
- it. (This won't actually modify the breakpoint list, but will
- physically remove the breakpoints from the child.) */
- detach_breakpoints (child_pid);
-#ifdef SOLIB_REMOVE_INFERIOR_HOOK
- SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
-#endif
-
- /* Detach from the child. */
- dont_repeat ();
-
- target_require_detach (child_pid, "", 1);
- }
-
- /* If we're to be following the child, then attach to it, detach
- from inferior_ptid, and set inferior_ptid to child_pid. */
- else if (follow_mode == follow_fork_mode_child)
- {
- char child_pid_spelling[100]; /* Arbitrary length. */
-
- followed_child = 1;
-
- /* Before detaching from the parent, detach all breakpoints from
- the child. Note that this only works if we're following vforks
- right away; if we've exec'd then the breakpoints are already detached
- and the shadow contents are out of date. */
- detach_breakpoints (child_pid);
-
- /* Before detaching from the parent, remove all breakpoints from it. */
- remove_breakpoints ();
-
- /* Also reset the solib inferior hook from the parent. */
-#ifdef SOLIB_REMOVE_INFERIOR_HOOK
- SOLIB_REMOVE_INFERIOR_HOOK (PIDGET (inferior_ptid));
-#endif
-
- /* Detach from the parent. */
- dont_repeat ();
- target_detach (NULL, 1);
-
- /* Attach to the child. */
- inferior_ptid = pid_to_ptid (child_pid);
- sprintf (child_pid_spelling, "%d", child_pid);
- dont_repeat ();
-
- target_require_attach (child_pid_spelling, 1);
-
- /* Was there a step_resume breakpoint? (There was if the user
- did a "next" at the fork() call.) If so, explicitly reset its
- thread number.
-
- step_resumes are a form of bp that are made to be per-thread.
- Since we created the step_resume bp when the parent process
- was being debugged, and now are switching to the child process,
- from the breakpoint package's viewpoint, that's a switch of
- "threads". We must update the bp's notion of which thread
- it is for, or it'll be ignored when it triggers... */
- /* As above, if we're following vforks at exec time then resetting the
- step resume breakpoint is probably wrong. */
- if (step_resume_breakpoint)
- breakpoint_re_set_thread (step_resume_breakpoint);
-
- /* Reinsert all breakpoints in the child. (The user may've set
- breakpoints after catching the fork, in which case those
- actually didn't get set in the child, but only in the parent.) */
- breakpoint_re_set ();
- insert_breakpoints ();
- }
-
- /* The parent and child of a vfork share the same address space.
- Also, on some targets the order in which vfork and exec events
- are received for parent in child requires some delicate handling
- of the events.
-
- For instance, on ptrace-based HPUX we receive the child's vfork
- event first, at which time the parent has been suspended by the
- OS and is essentially untouchable until the child's exit or second
- exec event arrives. At that time, the parent's vfork event is
- delivered to us, and that's when we see and decide how to follow
- the vfork. But to get to that point, we must continue the child
- until it execs or exits. To do that smoothly, all breakpoints
- must be removed from the child, in case there are any set between
- the vfork() and exec() calls. But removing them from the child
- also removes them from the parent, due to the shared-address-space
- nature of a vfork'd parent and child. On HPUX, therefore, we must
- take care to restore the bp's to the parent before we continue it.
- Else, it's likely that we may not stop in the expected place. (The
- worst scenario is when the user tries to step over a vfork() call;
- the step-resume bp must be restored for the step to properly stop
- in the parent after the call completes!)
-
- Sequence of events, as reported to gdb from HPUX:
-
- Parent Child Action for gdb to take
- -------------------------------------------------------
- 1 VFORK Continue child
- 2 EXEC
- 3 EXEC or EXIT
- 4 VFORK */
- if (has_vforked)
- {
- target_post_follow_vfork (parent_pid,
- followed_parent, child_pid, followed_child);
- }
-
- pending_follow.fork_event.saw_parent_fork = 0;
- pending_follow.fork_event.saw_child_fork = 0;
+ return target_follow_fork (follow_child);
}
-static void
-follow_fork (int parent_pid, int child_pid)
+void
+follow_inferior_reset_breakpoints (void)
{
- follow_inferior_fork (parent_pid, child_pid, 1, 0);
-}
+ /* Was there a step_resume breakpoint? (There was if the user
+ did a "next" at the fork() call.) If so, explicitly reset its
+ thread number.
+ step_resumes are a form of bp that are made to be per-thread.
+ Since we created the step_resume bp when the parent process
+ was being debugged, and now are switching to the child process,
+ from the breakpoint package's viewpoint, that's a switch of
+ "threads". We must update the bp's notion of which thread
+ it is for, or it'll be ignored when it triggers. */
-/* Forward declaration. */
-static void follow_exec (int, char *);
+ if (step_resume_breakpoint)
+ breakpoint_re_set_thread (step_resume_breakpoint);
-static void
-follow_vfork (int parent_pid, int child_pid)
-{
- follow_inferior_fork (parent_pid, child_pid, 0, 1);
+ /* Reinsert all breakpoints in the child. The user may have set
+ breakpoints after catching the fork, in which case those
+ were never set in the child, but only in the parent. This makes
+ sure the inserted breakpoints match the breakpoint list. */
+
+ breakpoint_re_set ();
+ insert_breakpoints ();
}
/* EXECD_PATHNAME is assumed to be non-NULL. */
#endif
/* If there were any forks/vforks/execs that were caught and are
- now to be followed, then do so. */
+ now to be followed, then do so. */
switch (pending_follow.kind)
{
- case (TARGET_WAITKIND_FORKED):
+ case TARGET_WAITKIND_FORKED:
+ case TARGET_WAITKIND_VFORKED:
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
- follow_fork (PIDGET (inferior_ptid),
- pending_follow.fork_event.child_pid);
- break;
-
- case (TARGET_WAITKIND_VFORKED):
- {
- int saw_child_exec = pending_follow.fork_event.saw_child_exec;
-
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
- follow_vfork (PIDGET (inferior_ptid),
- pending_follow.fork_event.child_pid);
-
- /* Did we follow the child, but not yet see the child's exec event?
- If so, then it actually ought to be waiting for us; we respond to
- parent vfork events. We don't actually want to resume the child
- in this situation; we want to just get its exec event. */
- if (!saw_child_exec &&
- (PIDGET (inferior_ptid) == pending_follow.fork_event.child_pid))
- should_resume = 0;
- }
+ if (follow_fork ())
+ should_resume = 0;
break;
- case (TARGET_WAITKIND_EXECD):
- /* If we saw a vfork event but couldn't follow it until we saw
- an exec, then now might be the time! */
- pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
+ case TARGET_WAITKIND_EXECD:
/* follow_exec is called as soon as the exec event is seen. */
+ pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
break;
default:
/* The first resume is not following a fork/vfork/exec. */
pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
- pending_follow.fork_event.saw_parent_fork = 0;
- pending_follow.fork_event.saw_child_fork = 0;
- pending_follow.fork_event.saw_child_exec = 0;
/* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
number_of_threads_in_syscalls = 0;
/* The following are the only cases in which we keep going;
the above cases end in a continue or goto. */
case TARGET_WAITKIND_FORKED:
+ case TARGET_WAITKIND_VFORKED:
stop_signal = TARGET_SIGNAL_TRAP;
pending_follow.kind = ecs->ws.kind;
- pending_follow.fork_event.saw_child_fork = 1;
pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
- stop_pc = read_pc_pid (ecs->ptid);
- ecs->saved_inferior_ptid = inferior_ptid;
- inferior_ptid = ecs->ptid;
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
- inferior_ptid = ecs->saved_inferior_ptid;
- goto process_event_stop_test;
+ stop_pc = read_pc ();
- /* If this a platform which doesn't allow a debugger to touch a
- vfork'd inferior until after it exec's, then we'd best keep
- our fingers entirely off the inferior, other than continuing
- it. This has the unfortunate side-effect that catchpoints
- of vforks will be ignored. But since the platform doesn't
- allow the inferior be touched at vfork time, there's really
- little choice. */
- case TARGET_WAITKIND_VFORKED:
- stop_signal = TARGET_SIGNAL_TRAP;
- pending_follow.kind = ecs->ws.kind;
+ /* Assume that catchpoints are not really software breakpoints. If
+ some future target implements them using software breakpoints then
+ that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
+ we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
+ bpstat_stop_status will not decrement the PC. */
- /* Is this a vfork of the parent? If so, then give any
- vfork catchpoints a chance to trigger now. (It's
- dangerous to do so if the child canot be touched until
- it execs, and the child has not yet exec'd. We probably
- should warn the user to that effect when the catchpoint
- triggers...) */
- if (ptid_equal (ecs->ptid, inferior_ptid))
- {
- pending_follow.fork_event.saw_parent_fork = 1;
- pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
- pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
- }
+ stop_bpstat = bpstat_stop_status (&stop_pc, 1);
- /* If we've seen the child's vfork event but cannot really touch
- the child until it execs, then we must continue the child now.
- Else, give any vfork catchpoints a chance to trigger now. */
- else
+ ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
+
+ /* If no catchpoint triggered for this, then keep going. */
+ if (ecs->random_signal)
{
- pending_follow.fork_event.saw_child_fork = 1;
- pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
- pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
- target_post_startup_inferior (pid_to_ptid
- (pending_follow.fork_event.
- child_pid));
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
}
-
- stop_pc = read_pc ();
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
- ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
goto process_event_stop_test;
case TARGET_WAITKIND_EXECD:
stop_pc = read_pc_pid (ecs->ptid);
ecs->saved_inferior_ptid = inferior_ptid;
inferior_ptid = ecs->ptid;
- /* The second argument of bpstat_stop_status is meant to help
- distinguish between a breakpoint trap and a singlestep trap.
- This is only important on targets where DECR_PC_AFTER_BREAK
- is non-zero. The prev_pc test is meant to distinguish between
- singlestepping a trap instruction, and singlestepping thru a
- jump to the instruction following a trap instruction. */
-
- stop_bpstat = bpstat_stop_status (&stop_pc,
- currently_stepping (ecs) &&
- prev_pc !=
- stop_pc - DECR_PC_AFTER_BREAK);
+
+ /* Assume that catchpoints are not really software breakpoints. If
+ some future target implements them using software breakpoints then
+ that target is responsible for fudging DECR_PC_AFTER_BREAK. Thus
+ we pass 1 for the NOT_A_SW_BREAKPOINT argument, so that
+ bpstat_stop_status will not decrement the PC. */
+
+ stop_bpstat = bpstat_stop_status (&stop_pc, 1);
+
ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
inferior_ptid = ecs->saved_inferior_ptid;
+
+ /* If no catchpoint triggered for this, then keep going. */
+ if (ecs->random_signal)
+ {
+ stop_signal = TARGET_SIGNAL_0;
+ keep_going (ecs);
+ return;
+ }
goto process_event_stop_test;
/* These syscall events are returned on HP-UX, as part of its
else
ecs->random_signal = 1;
- /* If a fork, vfork or exec event was seen, then there are two
- possible responses we can make:
-
- 1. If a catchpoint triggers for the event (ecs->random_signal == 0),
- then we must stop now and issue a prompt. We will resume
- the inferior when the user tells us to.
- 2. If no catchpoint triggers for the event (ecs->random_signal == 1),
- then we must resume the inferior now and keep checking.
-
- In either case, we must take appropriate steps to "follow" the
- the fork/vfork/exec when the inferior is resumed. For example,
- if follow-fork-mode is "child", then we must detach from the
- parent inferior and follow the new child inferior.
-
- In either case, setting pending_follow causes the next resume()
- to take the appropriate following action. */
-process_event_stop_test:
- if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
- {
- if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
- {
- trap_expected = 1;
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
- return;
- }
- }
- else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
- {
- if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
- {
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
- return;
- }
- }
- else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
- {
- pending_follow.kind = ecs->ws.kind;
- if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
- {
- trap_expected = 1;
- stop_signal = TARGET_SIGNAL_0;
- keep_going (ecs);
- return;
- }
- }
+process_event_stop_test:
/* For the program's own signals, act according to
the signal handling tables. */
set_longjmp_resume_breakpoint (jmp_buf_pc, get_current_frame ());
else
#endif /* 0 */
- set_longjmp_resume_breakpoint (jmp_buf_pc, NULL);
+ set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
ecs->handling_longjmp = 1; /* FIXME */
keep_going (ecs);
return;
check_for_old_step_resume_breakpoint ();
step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
if (breakpoints_inserted)
insert_breakpoints ();
}
step_frame_id; I don't think anyone thought to try it. */
check_for_old_step_resume_breakpoint ();
step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
if (breakpoints_inserted)
insert_breakpoints ();
}
xxx.section = find_pc_overlay (xxx.pc);
check_for_old_step_resume_breakpoint ();
step_resume_breakpoint =
- set_momentary_breakpoint (xxx, NULL, bp_step_resume);
+ set_momentary_breakpoint (xxx, null_frame_id, bp_step_resume);
insert_breakpoints ();
keep_going (ecs);
return;
is where the new fp value is established. */
check_for_old_step_resume_breakpoint ();
step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
if (breakpoints_inserted)
insert_breakpoints ();
/* We perhaps could set the frame if we kept track of what the
frame corresponding to prev_pc was. But we don't, so don't. */
through_sigtramp_breakpoint =
- set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
+ set_momentary_breakpoint (sr_sal, null_frame_id, bp_through_sigtramp);
if (breakpoints_inserted)
insert_breakpoints ();
established. */
check_for_old_step_resume_breakpoint ();
step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
+ set_momentary_breakpoint (sr_sal, null_frame_id, bp_step_resume);
if (breakpoints_inserted)
insert_breakpoints ();
check_for_old_step_resume_breakpoint ();
step_resume_breakpoint =
- set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
+ set_momentary_breakpoint (sr_sal, get_frame_id (get_current_frame ()),
+ bp_step_resume);
if (frame_id_p (step_frame_id)
&& !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
- /* FIXME: cagney/2002-12-01: Someone should modify the breakpoint
- code so that it uses a frame ID, instead of a frame address. */
- step_resume_breakpoint->frame = step_frame_id.base;
+ step_resume_breakpoint->frame_id = step_frame_id;
if (breakpoints_inserted)
insert_breakpoints ();
{
if (target_has_execution)
{
- /* Are we stopping for a vfork event? We only stop when we see
- the child's event. However, we may not yet have seen the
- parent's event. And, inferior_ptid is still set to the
- parent's pid, until we resume again and follow either the
- parent or child.
-
- To ensure that we can really touch inferior_ptid (aka, the
- parent process) -- which calls to functions like read_pc
- implicitly do -- wait on the parent if necessary. */
- if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
- && !pending_follow.fork_event.saw_parent_fork)
- {
- ptid_t parent_ptid;
-
- do
- {
- if (target_wait_hook)
- parent_ptid = target_wait_hook (pid_to_ptid (-1), &(ecs->ws));
- else
- parent_ptid = target_wait (pid_to_ptid (-1), &(ecs->ws));
- }
- while (!ptid_equal (parent_ptid, inferior_ptid));
- }
-
/* Assuming the inferior still exists, set these up for next
time, just like we did above if we didn't break out of the
loop. */
/* Make sure that the current_frame's pc is correct. This
is a correction for setting up the frame info before doing
DECR_PC_AFTER_BREAK */
- if (target_has_execution && get_current_frame ())
- (get_current_frame ())->pc = read_pc ();
+ if (target_has_execution)
+ /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
+ DECR_PC_AFTER_BREAK, the program counter can change. Ask the
+ frame code to check for this and sort out any resultant mess.
+ DECR_PC_AFTER_BREAK needs to just go away. */
+ deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
if (target_has_execution && breakpoints_inserted)
{
LOCATION: Print only location
SRC_AND_LOC: Print location and source line */
if (do_frame_printing)
- show_and_print_stack_frame (deprecated_selected_frame, -1, source_flag);
+ print_stack_frame (deprecated_selected_frame, -1, source_flag);
/* Display the auto-display expressions. */
do_displays ();
projects / deliverable / binutils-gdb.git / blobdiff