#include "inf-loop.h"
#include "event-loop.h"
#include "event-top.h"
-
-/* Note on this file's use of signals:
-
- We stop threads by sending a SIGSTOP. The use of SIGSTOP instead
- of another signal is not entirely significant; we just need for a
- signal to be delivered, so that we can intercept it. SIGSTOP's
- advantage is that it can not be blocked. A disadvantage is that it
- is not a real-time signal, so it can only be queued once; we do not
- keep track of other sources of SIGSTOP.
-
- Two other signals that can't be blocked are SIGCONT and SIGKILL.
- But we can't use them, because they have special behavior when the
- signal is generated - not when it is delivered. SIGCONT resumes
- the entire thread group and SIGKILL kills the entire thread group.
-
- A delivered SIGSTOP would stop the entire thread group, not just the
- thread we tkill'd. But we never let the SIGSTOP deliver; we always
- intercept and cancel it (by PTRACE_CONT without passing SIGSTOP).
-
- We could use a real-time signal instead. This would solve those
- problems; we could use PTRACE_GETSIGINFO to locate the specific
- stop signals sent by GDB. But we would still have to have some
- support for SIGSTOP, since PTRACE_ATTACH generates it, and there
- are races with trying to find a signal that is not blocked. */
+#include <pwd.h>
+#include <sys/types.h>
+#include "gdb_dirent.h"
+#include "xml-support.h"
+
+#ifdef HAVE_PERSONALITY
+# include <sys/personality.h>
+# if !HAVE_DECL_ADDR_NO_RANDOMIZE
+# define ADDR_NO_RANDOMIZE 0x0040000
+# endif
+#endif /* HAVE_PERSONALITY */
+
+/* This comment documents high-level logic of this file.
+
+Waiting for events in sync mode
+===============================
+
+When waiting for an event in a specific thread, we just use waitpid, passing
+the specific pid, and not passing WNOHANG.
+
+When waiting for an event in all threads, waitpid is not quite good. Prior to
+version 2.4, Linux can either wait for event in main thread, or in secondary
+threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might
+miss an event. The solution is to use non-blocking waitpid, together with
+sigsuspend. First, we use non-blocking waitpid to get an event in the main
+process, if any. Second, we use non-blocking waitpid with the __WCLONED
+flag to check for events in cloned processes. If nothing is found, we use
+sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something
+happened to a child process -- and SIGCHLD will be delivered both for events
+in main debugged process and in cloned processes. As soon as we know there's
+an event, we get back to calling nonblocking waitpid with and without __WCLONED.
+
+Note that SIGCHLD should be blocked between waitpid and sigsuspend calls,
+so that we don't miss a signal. If SIGCHLD arrives in between, when it's
+blocked, the signal becomes pending and sigsuspend immediately
+notices it and returns.
+
+Waiting for events in async mode
+================================
+
+In async mode, GDB should always be ready to handle both user input and target
+events, so neither blocking waitpid nor sigsuspend are viable
+options. Instead, we should notify the GDB main event loop whenever there's
+unprocessed event from the target. The only way to notify this event loop is
+to make it wait on input from a pipe, and write something to the pipe whenever
+there's event. Obviously, if we fail to notify the event loop if there's
+target event, it's bad. If we notify the event loop when there's no event
+from target, linux-nat.c will detect that there's no event, actually, and
+report event of type TARGET_WAITKIND_IGNORE, but it will waste time and
+better avoided.
+
+The main design point is that every time GDB is outside linux-nat.c, we have a
+SIGCHLD handler installed that is called when something happens to the target
+and notifies the GDB event loop. Also, the event is extracted from the target
+using waitpid and stored for future use. Whenever GDB core decides to handle
+the event, and calls into linux-nat.c, we disable SIGCHLD and process things
+as in sync mode, except that before waitpid call we check if there are any
+previously read events.
+
+It could happen that during event processing, we'll try to get more events
+than there are events in the local queue, which will result to waitpid call.
+Those waitpid calls, while blocking, are guarantied to always have
+something for waitpid to return. E.g., stopping a thread with SIGSTOP, and
+waiting for the lwp to stop.
+
+The event loop is notified about new events using a pipe. SIGCHLD handler does
+waitpid and writes the results in to a pipe. GDB event loop has the other end
+of the pipe among the sources. When event loop starts to process the event
+and calls a function in linux-nat.c, all events from the pipe are transferred
+into a local queue and SIGCHLD is blocked. Further processing goes as in sync
+mode. Before we return from linux_nat_wait, we transfer all unprocessed events
+from local queue back to the pipe, so that when we get back to event loop,
+event loop will notice there's something more to do.
+
+SIGCHLD is blocked when we're inside target_wait, so that should we actually
+want to wait for some more events, SIGCHLD handler does not steal them from
+us. Technically, it would be possible to add new events to the local queue but
+it's about the same amount of work as blocking SIGCHLD.
+
+This moving of events from pipe into local queue and back into pipe when we
+enter/leave linux-nat.c is somewhat ugly. Unfortunately, GDB event loop is
+home-grown and incapable to wait on any queue.
+
+Use of signals
+==============
+
+We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another
+signal is not entirely significant; we just need for a signal to be delivered,
+so that we can intercept it. SIGSTOP's advantage is that it can not be
+blocked. A disadvantage is that it is not a real-time signal, so it can only
+be queued once; we do not keep track of other sources of SIGSTOP.
+
+Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't
+use them, because they have special behavior when the signal is generated -
+not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL
+kills the entire thread group.
+
+A delivered SIGSTOP would stop the entire thread group, not just the thread we
+tkill'd. But we never let the SIGSTOP be delivered; we always intercept and
+cancel it (by PTRACE_CONT without passing SIGSTOP).
+
+We could use a real-time signal instead. This would solve those problems; we
+could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB.
+But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH
+generates it, and there are races with trying to find a signal that is not
+blocked. */
#ifndef O_LARGEFILE
#define O_LARGEFILE 0
value);
}
+static int disable_randomization = 1;
+
+static void
+show_disable_randomization (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+#ifdef HAVE_PERSONALITY
+ fprintf_filtered (file, _("\
+Disabling randomization of debuggee's virtual address space is %s.\n"),
+ value);
+#else /* !HAVE_PERSONALITY */
+ fputs_filtered (_("\
+Disabling randomization of debuggee's virtual address space is unsupported on\n\
+this platform.\n"), file);
+#endif /* !HAVE_PERSONALITY */
+}
+
+static void
+set_disable_randomization (char *args, int from_tty, struct cmd_list_element *c)
+{
+#ifndef HAVE_PERSONALITY
+ error (_("\
+Disabling randomization of debuggee's virtual address space is unsupported on\n\
+this platform."));
+#endif /* !HAVE_PERSONALITY */
+}
+
static int linux_parent_pid;
struct simple_pid_list
/* Async mode support */
-/* To listen to target events asynchronously, we install a SIGCHLD
- handler whose duty is to call waitpid (-1, ..., WNOHANG) to get all
- the pending events into a pipe. Whenever we're ready to handle
- events asynchronously, this pipe is registered as the waitable file
- handle in the event loop. When we get to entry target points
- coming out of the common code (target_wait, target_resume, ...),
- that are going to call waitpid, we block SIGCHLD signals, and
- remove all the events placed in the pipe into a local queue. All
- the subsequent calls to my_waitpid (a waitpid wrapper) check this
- local queue first. */
-
-/* True if async mode is currently on. */
-static int linux_nat_async_enabled;
-
/* Zero if the async mode, although enabled, is masked, which means
linux_nat_wait should behave as if async mode was off. */
static int linux_nat_async_mask_value = 1;
/* Number of queued events in the pipe. */
static volatile int linux_nat_num_queued_events;
-/* If async mode is on, true if we're listening for events; false if
- target events are blocked. */
-static int linux_nat_async_events_enabled;
+/* The possible SIGCHLD handling states. */
-static int linux_nat_async_events (int enable);
+enum sigchld_state
+{
+ /* SIGCHLD disabled, with action set to sigchld_handler, for the
+ sigsuspend in linux_nat_wait. */
+ sigchld_sync,
+ /* SIGCHLD enabled, with action set to async_sigchld_handler. */
+ sigchld_async,
+ /* Set SIGCHLD to default action. Used while creating an
+ inferior. */
+ sigchld_default
+};
+
+/* The current SIGCHLD handling state. */
+static enum sigchld_state linux_nat_async_events_state;
+
+static enum sigchld_state linux_nat_async_events (enum sigchld_state enable);
static void pipe_to_local_event_queue (void);
static void local_event_queue_to_pipe (void);
static void linux_nat_event_pipe_push (int pid, int status, int options);
static int linux_nat_async_mask (int mask);
static int kill_lwp (int lwpid, int signo);
+static int stop_callback (struct lwp_info *lp, void *data);
+
/* Captures the result of a successful waitpid call, along with the
options used in that call. */
struct waitpid_result
in the async SIGCHLD handler. */
static struct waitpid_result *waitpid_queue = NULL;
+/* Similarly to `waitpid', but check the local event queue instead of
+ querying the kernel queue. If PEEK, don't remove the event found
+ from the queue. */
+
static int
-queued_waitpid (int pid, int *status, int flags)
+queued_waitpid_1 (int pid, int *status, int flags, int peek)
{
struct waitpid_result *msg = waitpid_queue, *prev = NULL;
if (debug_linux_nat_async)
fprintf_unfiltered (gdb_stdlog,
"\
-QWPID: linux_nat_async_events_enabled(%d), linux_nat_num_queued_events(%d)\n",
- linux_nat_async_events_enabled,
+QWPID: linux_nat_async_events_state(%d), linux_nat_num_queued_events(%d)\n",
+ linux_nat_async_events_state,
linux_nat_num_queued_events);
if (flags & __WALL)
{
int pid;
- if (prev)
- prev->next = msg->next;
- else
- waitpid_queue = msg->next;
-
- msg->next = NULL;
if (status)
*status = msg->status;
pid = msg->pid;
if (debug_linux_nat_async)
fprintf_unfiltered (gdb_stdlog, "QWPID: pid(%d), status(%x)\n",
pid, msg->status);
- xfree (msg);
+
+ if (!peek)
+ {
+ if (prev)
+ prev->next = msg->next;
+ else
+ waitpid_queue = msg->next;
+
+ msg->next = NULL;
+ xfree (msg);
+ }
return pid;
}
return -1;
}
+/* Similarly to `waitpid', but check the local event queue. */
+
+static int
+queued_waitpid (int pid, int *status, int flags)
+{
+ return queued_waitpid_1 (pid, status, flags, 0);
+}
+
static void
push_waitpid (int pid, int status, int options)
{
int ret;
/* There should be no concurrent calls to waitpid. */
- gdb_assert (!linux_nat_async_events_enabled);
+ gdb_assert (linux_nat_async_events_state == sigchld_sync);
ret = queued_waitpid (pid, status, flags);
if (ret != -1)
{
int child_pid, ret, status;
long second_pid;
+ enum sigchld_state async_events_original_state;
+
+ async_events_original_state = linux_nat_async_events (sigchld_sync);
linux_supports_tracefork_flag = 0;
linux_supports_tracevforkdone_flag = 0;
if (ret != 0)
{
warning (_("linux_test_for_tracefork: failed to kill child"));
+ linux_nat_async_events (async_events_original_state);
return;
}
warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from "
"killed child"), status);
+ linux_nat_async_events (async_events_original_state);
return;
}
if (ret != 0)
warning (_("linux_test_for_tracefork: failed to kill child"));
my_waitpid (child_pid, &status, 0);
+
+ linux_nat_async_events (async_events_original_state);
}
/* Return non-zero iff we have tracefork functionality available.
parent_pid = ptid_get_lwp (last_ptid);
if (parent_pid == 0)
parent_pid = ptid_get_pid (last_ptid);
- child_pid = last_status.value.related_pid;
+ child_pid = PIDGET (last_status.value.related_pid);
if (! follow_child)
{
else
{
struct fork_info *fp;
+
+ /* Add process to GDB's tables. */
+ add_inferior (child_pid);
+
/* Retain child fork in ptrace (stopped) state. */
fp = find_fork_pid (child_pid);
if (!fp)
}
else
{
+ struct thread_info *last_tp = find_thread_pid (last_ptid);
+ struct thread_info *tp;
char child_pid_spelling[40];
+ /* Copy user stepping state to the new inferior thread. */
+ struct breakpoint *step_resume_breakpoint = last_tp->step_resume_breakpoint;
+ CORE_ADDR step_range_start = last_tp->step_range_start;
+ CORE_ADDR step_range_end = last_tp->step_range_end;
+ struct frame_id step_frame_id = last_tp->step_frame_id;
+
+ /* Otherwise, deleting the parent would get rid of this
+ breakpoint. */
+ last_tp->step_resume_breakpoint = NULL;
+
/* Needed to keep the breakpoint lists in sync. */
if (! has_vforked)
detach_breakpoints (child_pid);
safely resume it. */
if (has_vforked)
- linux_parent_pid = parent_pid;
+ {
+ linux_parent_pid = parent_pid;
+ detach_inferior (parent_pid);
+ }
else if (!detach_fork)
{
struct fork_info *fp;
target_detach (NULL, 0);
inferior_ptid = ptid_build (child_pid, child_pid, 0);
+ add_inferior (child_pid);
/* Reinstall ourselves, since we might have been removed in
target_detach (which does other necessary cleanup). */
linux_nat_switch_fork (inferior_ptid);
check_for_thread_db ();
+ tp = inferior_thread ();
+ tp->step_resume_breakpoint = step_resume_breakpoint;
+ tp->step_range_start = step_range_start;
+ tp->step_range_end = step_range_end;
+ tp->step_frame_id = step_frame_id;
+
/* Reset breakpoints in the child as appropriate. */
follow_inferior_reset_breakpoints ();
}
static int num_lwps;
\f
-/* If the last reported event was a SIGTRAP, this variable is set to
- the process id of the LWP/thread that got it. */
-ptid_t trap_ptid;
-\f
-
-/* Since we cannot wait (in linux_nat_wait) for the initial process and
- any cloned processes with a single call to waitpid, we have to use
- the WNOHANG flag and call waitpid in a loop. To optimize
- things a bit we use `sigsuspend' to wake us up when a process has
- something to report (it will send us a SIGCHLD if it has). To make
- this work we have to juggle with the signal mask. We save the
- original signal mask such that we can restore it before creating a
- new process in order to avoid blocking certain signals in the
- inferior. We then block SIGCHLD during the waitpid/sigsuspend
- loop. */
-
/* Original signal mask. */
static sigset_t normal_mask;
/* SIGCHLD action for asynchronous mode. */
static struct sigaction async_sigchld_action;
+
+/* SIGCHLD default action, to pass to new inferiors. */
+static struct sigaction sigchld_default_action;
\f
/* Prototypes for local functions. */
{
struct lwp_info *lp;
- init_thread_list ();
init_lwp_list ();
lp = add_lwp (new_ptid);
- add_thread_silent (new_ptid);
lp->stopped = 1;
-}
-
-/* Record a PTID for later deletion. */
-
-struct saved_ptids
-{
- ptid_t ptid;
- struct saved_ptids *next;
-};
-static struct saved_ptids *threads_to_delete;
-static void
-record_dead_thread (ptid_t ptid)
-{
- struct saved_ptids *p = xmalloc (sizeof (struct saved_ptids));
- p->ptid = ptid;
- p->next = threads_to_delete;
- threads_to_delete = p;
-}
-
-/* Delete any dead threads which are not the current thread. */
-
-static void
-prune_lwps (void)
-{
- struct saved_ptids **p = &threads_to_delete;
-
- while (*p)
- if (! ptid_equal ((*p)->ptid, inferior_ptid))
- {
- struct saved_ptids *tmp = *p;
- delete_thread (tmp->ptid);
- *p = tmp->next;
- xfree (tmp);
- }
- else
- p = &(*p)->next;
+ init_thread_list ();
+ add_thread_silent (new_ptid);
}
/* Handle the exit of a single thread LP. */
if (print_thread_events)
printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid));
- /* Core GDB cannot deal with us deleting the current thread. */
- if (!ptid_equal (lp->ptid, inferior_ptid))
- delete_thread (lp->ptid);
- else
- record_dead_thread (lp->ptid);
+ delete_thread (lp->ptid);
}
delete_lwp (lp->ptid);
lin_lwp_attach_lwp (ptid_t ptid)
{
struct lwp_info *lp;
- int async_events_were_enabled = 0;
+ enum sigchld_state async_events_original_state;
gdb_assert (is_lwp (ptid));
- if (target_can_async_p ())
- async_events_were_enabled = linux_nat_async_events (0);
+ async_events_original_state = linux_nat_async_events (sigchld_sync);
lp = find_lwp_pid (ptid);
lp->stopped = 1;
}
- if (async_events_were_enabled)
- linux_nat_async_events (1);
-
+ linux_nat_async_events (async_events_original_state);
return 0;
}
static void
-linux_nat_create_inferior (char *exec_file, char *allargs, char **env,
+linux_nat_create_inferior (struct target_ops *ops,
+ char *exec_file, char *allargs, char **env,
int from_tty)
{
int saved_async = 0;
+#ifdef HAVE_PERSONALITY
+ int personality_orig = 0, personality_set = 0;
+#endif /* HAVE_PERSONALITY */
/* The fork_child mechanism is synchronous and calls target_wait, so
we have to mask the async mode. */
if (target_can_async_p ())
+ /* Mask async mode. Creating a child requires a loop calling
+ wait_for_inferior currently. */
saved_async = linux_nat_async_mask (0);
else
{
sigdelset (&suspend_mask, SIGCHLD);
}
- linux_ops->to_create_inferior (exec_file, allargs, env, from_tty);
+ /* Set SIGCHLD to the default action, until after execing the child,
+ since the inferior inherits the superior's signal mask. It will
+ be blocked again in linux_nat_wait, which is only reached after
+ the inferior execing. */
+ linux_nat_async_events (sigchld_default);
+
+#ifdef HAVE_PERSONALITY
+ if (disable_randomization)
+ {
+ errno = 0;
+ personality_orig = personality (0xffffffff);
+ if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE))
+ {
+ personality_set = 1;
+ personality (personality_orig | ADDR_NO_RANDOMIZE);
+ }
+ if (errno != 0 || (personality_set
+ && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
+ warning (_("Error disabling address space randomization: %s"),
+ safe_strerror (errno));
+ }
+#endif /* HAVE_PERSONALITY */
+
+ linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty);
+
+#ifdef HAVE_PERSONALITY
+ if (personality_set)
+ {
+ errno = 0;
+ personality (personality_orig);
+ if (errno != 0)
+ warning (_("Error restoring address space randomization: %s"),
+ safe_strerror (errno));
+ }
+#endif /* HAVE_PERSONALITY */
if (saved_async)
linux_nat_async_mask (saved_async);
}
static void
-linux_nat_attach (char *args, int from_tty)
+linux_nat_attach (struct target_ops *ops, char *args, int from_tty)
{
struct lwp_info *lp;
int status;
+ ptid_t ptid;
/* FIXME: We should probably accept a list of process id's, and
attach all of them. */
- linux_ops->to_attach (args, from_tty);
+ linux_ops->to_attach (ops, args, from_tty);
if (!target_can_async_p ())
{
sigdelset (&suspend_mask, SIGCHLD);
}
+ /* The ptrace base target adds the main thread with (pid,0,0)
+ format. Decorate it with lwp info. */
+ ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
+ thread_change_ptid (inferior_ptid, ptid);
+
/* Add the initial process as the first LWP to the list. */
- inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
- lp = add_lwp (inferior_ptid);
+ lp = add_lwp (ptid);
status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned,
&lp->signalled);
lp->stopped = 1;
- /* If this process is not using thread_db, then we still don't
- detect any other threads, but add at least this one. */
- add_thread_silent (lp->ptid);
-
/* Save the wait status to report later. */
lp->resumed = 1;
if (debug_linux_nat)
events are always cached in waitpid_queue. */
*status = 0;
- if (GET_LWP (lp->ptid) == GET_LWP (last_ptid))
+
+ if (non_stop)
{
- if (stop_signal != TARGET_SIGNAL_0
- && signal_pass_state (stop_signal))
- *status = W_STOPCODE (target_signal_to_host (stop_signal));
+ enum target_signal signo = TARGET_SIGNAL_0;
+
+ if (is_executing (lp->ptid))
+ {
+ /* If the core thought this lwp was executing --- e.g., the
+ executing property hasn't been updated yet, but the
+ thread has been stopped with a stop_callback /
+ stop_wait_callback sequence (see linux_nat_detach for
+ example) --- we can only have pending events in the local
+ queue. */
+ if (queued_waitpid (GET_LWP (lp->ptid), status, __WALL) != -1)
+ {
+ if (WIFSTOPPED (*status))
+ signo = target_signal_from_host (WSTOPSIG (*status));
+
+ /* If not stopped, then the lwp is gone, no use in
+ resending a signal. */
+ }
+ }
+ else
+ {
+ /* If the core knows the thread is not executing, then we
+ have the last signal recorded in
+ thread_info->stop_signal. */
+
+ struct thread_info *tp = find_thread_pid (lp->ptid);
+ signo = tp->stop_signal;
+ }
+
+ if (signo != TARGET_SIGNAL_0
+ && !signal_pass_state (signo))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "\
+GPT: lwp %s had signal %s, but it is in no pass state\n",
+ target_pid_to_str (lp->ptid),
+ target_signal_to_string (signo));
+ }
+ else
+ {
+ if (signo != TARGET_SIGNAL_0)
+ *status = W_STOPCODE (target_signal_to_host (signo));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "GPT: lwp %s as pending signal %s\n",
+ target_pid_to_str (lp->ptid),
+ target_signal_to_string (signo));
+ }
}
- else if (target_can_async_p ())
- queued_waitpid (GET_LWP (lp->ptid), status, __WALL);
else
- *status = lp->status;
+ {
+ if (GET_LWP (lp->ptid) == GET_LWP (last_ptid))
+ {
+ struct thread_info *tp = find_thread_pid (lp->ptid);
+ if (tp->stop_signal != TARGET_SIGNAL_0
+ && signal_pass_state (tp->stop_signal))
+ *status = W_STOPCODE (target_signal_to_host (tp->stop_signal));
+ }
+ else if (target_can_async_p ())
+ queued_waitpid (GET_LWP (lp->ptid), status, __WALL);
+ else
+ *status = lp->status;
+ }
return 0;
}
}
static void
-linux_nat_detach (char *args, int from_tty)
+linux_nat_detach (struct target_ops *ops, char *args, int from_tty)
{
int pid;
int status;
if (target_can_async_p ())
linux_nat_async (NULL, 0);
+ /* Stop all threads before detaching. ptrace requires that the
+ thread is stopped to sucessfully detach. */
+ iterate_over_lwps (stop_callback, NULL);
+ /* ... and wait until all of them have reported back that
+ they're no longer running. */
+ iterate_over_lwps (stop_wait_callback, NULL);
+
iterate_over_lwps (detach_callback, NULL);
/* Only the initial process should be left right now. */
target_pid_to_str (lwp_list->ptid));
}
- trap_ptid = null_ptid;
-
/* Destroy LWP info; it's no longer valid. */
init_lwp_list ();
pid = GET_PID (inferior_ptid);
inferior_ptid = pid_to_ptid (pid);
- linux_ops->to_detach (args, from_tty);
+ linux_ops->to_detach (ops, args, from_tty);
if (target_can_async_p ())
drain_queued_events (pid);
lp->step = 0;
memset (&lp->siginfo, 0, sizeof (lp->siginfo));
}
+ else if (lp->stopped && debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "RC: Not resuming sibling %s (has pending)\n",
+ target_pid_to_str (lp->ptid));
+ else if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "RC: Not resuming sibling %s (not stopped)\n",
+ target_pid_to_str (lp->ptid));
return 0;
}
signo ? strsignal (signo) : "0",
target_pid_to_str (inferior_ptid));
- prune_lwps ();
-
if (target_can_async_p ())
/* Block events while we're here. */
- linux_nat_async_events (0);
+ linux_nat_async_events (sigchld_sync);
/* A specific PTID means `step only this process id'. */
resume_all = (PIDGET (ptid) == -1);
- if (resume_all)
- iterate_over_lwps (resume_set_callback, NULL);
- else
- iterate_over_lwps (resume_clear_callback, NULL);
+ if (non_stop && resume_all)
+ internal_error (__FILE__, __LINE__,
+ "can't resume all in non-stop mode");
+
+ if (!non_stop)
+ {
+ if (resume_all)
+ iterate_over_lwps (resume_set_callback, NULL);
+ else
+ iterate_over_lwps (resume_clear_callback, NULL);
+ }
/* If PID is -1, it's the current inferior that should be
handled specially. */
lp = find_lwp_pid (ptid);
gdb_assert (lp != NULL);
+ /* Convert to something the lower layer understands. */
ptid = pid_to_ptid (GET_LWP (lp->ptid));
/* Remember if we're stepping. */
if (lp->status && WIFSTOPPED (lp->status))
{
- int saved_signo = target_signal_from_host (WSTOPSIG (lp->status));
+ int saved_signo;
+ struct inferior *inf;
- if (signal_stop_state (saved_signo) == 0
+ inf = find_inferior_pid (ptid_get_pid (ptid));
+ gdb_assert (inf);
+ saved_signo = target_signal_from_host (WSTOPSIG (lp->status));
+
+ /* Defer to common code if we're gaining control of the
+ inferior. */
+ if (inf->stop_soon == NO_STOP_QUIETLY
+ && signal_stop_state (saved_signo) == 0
&& signal_print_state (saved_signo) == 0
&& signal_pass_state (saved_signo) == 1)
{
signo ? strsignal (signo) : "0");
if (target_can_async_p ())
- {
- target_executing = 1;
- target_async (inferior_event_handler, 0);
- }
+ target_async (inferior_event_handler, 0);
}
/* Issue kill to specified lwp. */
_("wait returned unexpected status 0x%x"), status);
}
- ourstatus->value.related_pid = new_pid;
+ ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0);
if (event == PTRACE_EVENT_FORK)
ourstatus->kind = TARGET_WAITKIND_FORKED;
ourstatus->kind = TARGET_WAITKIND_VFORKED;
else
{
+ struct cleanup *old_chain;
+
ourstatus->kind = TARGET_WAITKIND_IGNORE;
new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid)));
new_lp->cloned = 1;
+ new_lp->stopped = 1;
if (WSTOPSIG (status) != SIGSTOP)
{
else
status = 0;
- if (stopping)
- new_lp->stopped = 1;
- else
+ if (non_stop)
+ {
+ /* Add the new thread to GDB's lists as soon as possible
+ so that:
+
+ 1) the frontend doesn't have to wait for a stop to
+ display them, and,
+
+ 2) we tag it with the correct running state. */
+
+ /* If the thread_db layer is active, let it know about
+ this new thread, and add it to GDB's list. */
+ if (!thread_db_attach_lwp (new_lp->ptid))
+ {
+ /* We're not using thread_db. Add it to GDB's
+ list. */
+ target_post_attach (GET_LWP (new_lp->ptid));
+ add_thread (new_lp->ptid);
+ }
+
+ if (!stopping)
+ {
+ set_running (new_lp->ptid, 1);
+ set_executing (new_lp->ptid, 1);
+ }
+ }
+
+ if (!stopping)
{
+ new_lp->stopped = 0;
new_lp->resumed = 1;
- ptrace (PTRACE_CONT, lp->waitstatus.value.related_pid, 0,
+ ptrace (PTRACE_CONT, new_pid, 0,
status ? WSTOPSIG (status) : 0);
}
linux_parent_pid = 0;
}
+ /* At this point, all inserted breakpoints are gone. Doing this
+ as soon as we detect an exec prevents the badness of deleting
+ a breakpoint writing the current "shadow contents" to lift
+ the bp. That shadow is NOT valid after an exec.
+
+ Note that we have to do this after the detach_breakpoints
+ call above, otherwise breakpoints wouldn't be lifted from the
+ parent on a vfork, because detach_breakpoints would think
+ that breakpoints are not inserted. */
+ mark_breakpoints_out ();
return 0;
}
return 0;
}
-/* Wait until LP is stopped. If DATA is non-null it is interpreted as
- a pointer to a set of signals to be flushed immediately. */
+/* Return non-zero if LWP PID has a pending SIGINT. */
static int
-stop_wait_callback (struct lwp_info *lp, void *data)
+linux_nat_has_pending_sigint (int pid)
{
- sigset_t *flush_mask = data;
+ sigset_t pending, blocked, ignored;
+ int i;
+
+ linux_proc_pending_signals (pid, &pending, &blocked, &ignored);
+ if (sigismember (&pending, SIGINT)
+ && !sigismember (&ignored, SIGINT))
+ return 1;
+
+ return 0;
+}
+
+/* Set a flag in LP indicating that we should ignore its next SIGINT. */
+
+static int
+set_ignore_sigint (struct lwp_info *lp, void *data)
+{
+ /* If a thread has a pending SIGINT, consume it; otherwise, set a
+ flag to consume the next one. */
+ if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status)
+ && WSTOPSIG (lp->status) == SIGINT)
+ lp->status = 0;
+ else
+ lp->ignore_sigint = 1;
+
+ return 0;
+}
+
+/* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
+ This function is called after we know the LWP has stopped; if the LWP
+ stopped before the expected SIGINT was delivered, then it will never have
+ arrived. Also, if the signal was delivered to a shared queue and consumed
+ by a different thread, it will never be delivered to this LWP. */
+
+static void
+maybe_clear_ignore_sigint (struct lwp_info *lp)
+{
+ if (!lp->ignore_sigint)
+ return;
+
+ if (!linux_nat_has_pending_sigint (GET_LWP (lp->ptid)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "MCIS: Clearing bogus flag for %s\n",
+ target_pid_to_str (lp->ptid));
+ lp->ignore_sigint = 0;
+ }
+}
+
+/* Wait until LP is stopped. */
+
+static int
+stop_wait_callback (struct lwp_info *lp, void *data)
+{
if (!lp->stopped)
{
int status;
if (status == 0)
return 0;
- /* Ignore any signals in FLUSH_MASK. */
- if (flush_mask && sigismember (flush_mask, WSTOPSIG (status)))
+ if (lp->ignore_sigint && WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGINT)
{
- if (!lp->signalled)
- {
- lp->stopped = 1;
- return 0;
- }
+ lp->ignore_sigint = 0;
errno = 0;
ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
- "PTRACE_CONT %s, 0, 0 (%s)\n",
+ "PTRACE_CONT %s, 0, 0 (%s) (discarding SIGINT)\n",
target_pid_to_str (lp->ptid),
errno ? safe_strerror (errno) : "OK");
- return stop_wait_callback (lp, flush_mask);
+ return stop_wait_callback (lp, NULL);
}
+ maybe_clear_ignore_sigint (lp);
+
if (WSTOPSIG (status) != SIGSTOP)
{
if (WSTOPSIG (status) == SIGTRAP)
}
/* Hold this event/waitstatus while we check to see if
there are any more (we still want to get that SIGSTOP). */
- stop_wait_callback (lp, data);
+ stop_wait_callback (lp, NULL);
if (target_can_async_p ())
{
/* There was no gdb breakpoint set at pc. Put
the event back in the queue. */
if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "SWC: kill %s, %s\n",
- target_pid_to_str (lp->ptid),
- status_to_str ((int) status));
- kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
+ fprintf_unfiltered (gdb_stdlog, "\
+SWC: leaving SIGTRAP in local queue of %s\n", target_pid_to_str (lp->ptid));
+ push_waitpid (GET_LWP (lp->ptid),
+ W_STOPCODE (SIGTRAP),
+ lp->cloned ? __WCLONE : 0);
}
}
else
/* Hold this event/waitstatus while we check to see if
there are any more (we still want to get that SIGSTOP). */
- stop_wait_callback (lp, data);
+ stop_wait_callback (lp, NULL);
/* If the lp->status field is still empty, use it to
hold this event. If not, then this event must be
return 0;
}
-/* Check whether PID has any pending signals in FLUSH_MASK. If so set
- the appropriate bits in PENDING, and return 1 - otherwise return 0. */
-
-static int
-linux_nat_has_pending (int pid, sigset_t *pending, sigset_t *flush_mask)
-{
- sigset_t blocked, ignored;
- int i;
-
- linux_proc_pending_signals (pid, pending, &blocked, &ignored);
-
- if (!flush_mask)
- return 0;
-
- for (i = 1; i < NSIG; i++)
- if (sigismember (pending, i))
- if (!sigismember (flush_mask, i)
- || sigismember (&blocked, i)
- || sigismember (&ignored, i))
- sigdelset (pending, i);
-
- if (sigisemptyset (pending))
- return 0;
-
- return 1;
-}
-
-/* DATA is interpreted as a mask of signals to flush. If LP has
- signals pending, and they are all in the flush mask, then arrange
- to flush them. LP should be stopped, as should all other threads
- it might share a signal queue with. */
-
-static int
-flush_callback (struct lwp_info *lp, void *data)
-{
- sigset_t *flush_mask = data;
- sigset_t pending, intersection, blocked, ignored;
- int pid, status;
-
- /* Normally, when an LWP exits, it is removed from the LWP list. The
- last LWP isn't removed till later, however. So if there is only
- one LWP on the list, make sure it's alive. */
- if (lwp_list == lp && lp->next == NULL)
- if (!linux_nat_thread_alive (lp->ptid))
- return 0;
-
- /* Just because the LWP is stopped doesn't mean that new signals
- can't arrive from outside, so this function must be careful of
- race conditions. However, because all threads are stopped, we
- can assume that the pending mask will not shrink unless we resume
- the LWP, and that it will then get another signal. We can't
- control which one, however. */
-
- if (lp->status)
- {
- if (debug_linux_nat)
- printf_unfiltered (_("FC: LP has pending status %06x\n"), lp->status);
- if (WIFSTOPPED (lp->status) && sigismember (flush_mask, WSTOPSIG (lp->status)))
- lp->status = 0;
- }
-
- /* While there is a pending signal we would like to flush, continue
- the inferior and collect another signal. But if there's already
- a saved status that we don't want to flush, we can't resume the
- inferior - if it stopped for some other reason we wouldn't have
- anywhere to save the new status. In that case, we must leave the
- signal unflushed (and possibly generate an extra SIGINT stop).
- That's much less bad than losing a signal. */
- while (lp->status == 0
- && linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask))
- {
- int ret;
-
- errno = 0;
- ret = ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stderr,
- "FC: Sent PTRACE_CONT, ret %d %d\n", ret, errno);
-
- lp->stopped = 0;
- stop_wait_callback (lp, flush_mask);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stderr,
- "FC: Wait finished; saved status is %d\n",
- lp->status);
- }
-
- return 0;
-}
-
/* Return non-zero if LP has a wait status pending. */
static int
gdb_assert (count != NULL);
- /* Count only LWPs that have a SIGTRAP event pending. */
- if (lp->status != 0
+ /* Count only resumed LWPs that have a SIGTRAP event pending. */
+ if (lp->status != 0 && lp->resumed
&& WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP)
(*count)++;
gdb_assert (selector != NULL);
- /* Select only LWPs that have a SIGTRAP event pending. */
- if (lp->status != 0
+ /* Select only resumed LWPs that have a SIGTRAP event pending. */
+ if (lp->status != 0 && lp->resumed
&& WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP)
if ((*selector)-- == 0)
return 1;
not the end of the debugged application and should be
ignored. */
if (num_lwps > 0)
- {
- /* Make sure there is at least one thread running. */
- gdb_assert (iterate_over_lwps (running_callback, NULL));
-
- /* Discard the event. */
- return NULL;
- }
+ return NULL;
}
/* Check if the current LWP has previously exited. In the nptl
return NULL;
}
+ /* Make sure we don't report a SIGINT that we have already displayed
+ for another thread. */
+ if (lp->ignore_sigint
+ && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Delayed SIGINT caught for %s.\n",
+ target_pid_to_str (lp->ptid));
+
+ /* This is a delayed SIGINT. */
+ lp->ignore_sigint = 0;
+
+ registers_changed ();
+ linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s %s, 0, 0 (discard SIGINT)\n",
+ lp->step ?
+ "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid));
+
+ lp->stopped = 0;
+ gdb_assert (lp->resumed);
+
+ /* Discard the event. */
+ return NULL;
+ }
+
/* An interesting event. */
gdb_assert (lp);
return lp;
int options = 0;
int status = 0;
pid_t pid = PIDGET (ptid);
- sigset_t flush_mask;
if (debug_linux_nat_async)
fprintf_unfiltered (gdb_stdlog, "LLW: enter\n");
{
gdb_assert (!is_lwp (inferior_ptid));
- inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
- GET_PID (inferior_ptid));
+ /* Upgrade the main thread's ptid. */
+ thread_change_ptid (inferior_ptid,
+ BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid)));
+
lp = add_lwp (inferior_ptid);
lp->resumed = 1;
- /* Add the main thread to GDB's thread list. */
- add_thread_silent (lp->ptid);
}
- sigemptyset (&flush_mask);
-
- if (target_can_async_p ())
- /* Block events while we're here. */
- target_async (NULL, 0);
+ /* Block events while we're here. */
+ linux_nat_async_events (sigchld_sync);
retry:
if (WIFSTOPPED (status))
{
int signo = target_signal_from_host (WSTOPSIG (status));
+ struct inferior *inf;
- /* If we get a signal while single-stepping, we may need special
- care, e.g. to skip the signal handler. Defer to common code. */
+ inf = find_inferior_pid (ptid_get_pid (lp->ptid));
+ gdb_assert (inf);
+
+ /* Defer to common code if we get a signal while
+ single-stepping, since that may need special care, e.g. to
+ skip the signal handler, or, if we're gaining control of the
+ inferior. */
if (!lp->step
+ && inf->stop_soon == NO_STOP_QUIETLY
&& signal_stop_state (signo) == 0
&& signal_print_state (signo) == 0
&& signal_pass_state (signo) == 1)
goto retry;
}
- if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0)
+ if (!non_stop)
{
- /* If ^C/BREAK is typed at the tty/console, SIGINT gets
- forwarded to the entire process group, that is, all LWP's
- will receive it. Since we only want to report it once,
- we try to flush it from all LWPs except this one. */
- sigaddset (&flush_mask, SIGINT);
+ /* Only do the below in all-stop, as we currently use SIGINT
+ to implement target_stop (see linux_nat_stop) in
+ non-stop. */
+ if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0)
+ {
+ /* If ^C/BREAK is typed at the tty/console, SIGINT gets
+ forwarded to the entire process group, that is, all LWPs
+ will receive it - unless they're using CLONE_THREAD to
+ share signals. Since we only want to report it once, we
+ mark it as ignored for all LWPs except this one. */
+ iterate_over_lwps (set_ignore_sigint, NULL);
+ lp->ignore_sigint = 0;
+ }
+ else
+ maybe_clear_ignore_sigint (lp);
}
}
fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n",
status_to_str (status), target_pid_to_str (lp->ptid));
- /* Now stop all other LWP's ... */
- iterate_over_lwps (stop_callback, NULL);
+ if (!non_stop)
+ {
+ /* Now stop all other LWP's ... */
+ iterate_over_lwps (stop_callback, NULL);
- /* ... and wait until all of them have reported back that they're no
- longer running. */
- iterate_over_lwps (stop_wait_callback, &flush_mask);
- iterate_over_lwps (flush_callback, &flush_mask);
+ /* ... and wait until all of them have reported back that
+ they're no longer running. */
+ iterate_over_lwps (stop_wait_callback, NULL);
- /* If we're not waiting for a specific LWP, choose an event LWP from
- among those that have had events. Giving equal priority to all
- LWPs that have had events helps prevent starvation. */
- if (pid == -1)
- select_event_lwp (&lp, &status);
+ /* If we're not waiting for a specific LWP, choose an event LWP
+ from among those that have had events. Giving equal priority
+ to all LWPs that have had events helps prevent
+ starvation. */
+ if (pid == -1)
+ select_event_lwp (&lp, &status);
+ }
/* Now that we've selected our final event LWP, cancel any
breakpoints in other LWPs that have hit a GDB breakpoint. See
if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP)
{
- trap_ptid = lp->ptid;
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
- "LLW: trap_ptid is %s.\n",
- target_pid_to_str (trap_ptid));
+ "LLW: trap ptid is %s.\n",
+ target_pid_to_str (lp->ptid));
}
- else
- trap_ptid = null_ptid;
if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
{
if (last.kind == TARGET_WAITKIND_FORKED
|| last.kind == TARGET_WAITKIND_VFORKED)
{
- ptrace (PT_KILL, last.value.related_pid, 0, 0);
+ ptrace (PT_KILL, PIDGET (last.value.related_pid), 0, 0);
wait (&status);
}
}
else
{
+ /* Stop all threads before killing them, since ptrace requires
+ that the thread is stopped to sucessfully PTRACE_KILL. */
+ iterate_over_lwps (stop_callback, NULL);
+ /* ... and wait until all of them have reported back that
+ they're no longer running. */
+ iterate_over_lwps (stop_wait_callback, NULL);
+
/* Kill all LWP's ... */
iterate_over_lwps (kill_callback, NULL);
}
static void
-linux_nat_mourn_inferior (void)
+linux_nat_mourn_inferior (struct target_ops *ops)
{
- trap_ptid = null_ptid;
-
/* Destroy LWP info; it's no longer valid. */
init_lwp_list ();
/* Normal case, no other forks available. */
if (target_can_async_p ())
linux_nat_async (NULL, 0);
- linux_ops->to_mourn_inferior ();
+ linux_ops->to_mourn_inferior (ops);
}
else
/* Multi-fork case. The current inferior_ptid has exited, but
static int
linux_nat_thread_alive (ptid_t ptid)
{
+ int err;
+
gdb_assert (is_lwp (ptid));
- errno = 0;
- ptrace (PTRACE_PEEKUSER, GET_LWP (ptid), 0, 0);
+ /* Send signal 0 instead of anything ptrace, because ptracing a
+ running thread errors out claiming that the thread doesn't
+ exist. */
+ err = kill_lwp (GET_LWP (ptid), 0);
+
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
- "LLTA: PTRACE_PEEKUSER %s, 0, 0 (%s)\n",
+ "LLTA: KILL(SIG0) %s (%s)\n",
target_pid_to_str (ptid),
- errno ? safe_strerror (errno) : "OK");
+ err ? safe_strerror (err) : "OK");
- /* Not every Linux kernel implements PTRACE_PEEKUSER. But we can
- handle that case gracefully since ptrace will first do a lookup
- for the process based upon the passed-in pid. If that fails we
- will get either -ESRCH or -EPERM, otherwise the child exists and
- is alive. */
- if (errno == ESRCH || errno == EPERM)
+ if (err != 0)
return 0;
return 1;
static void
sigchld_handler (int signo)
{
- if (linux_nat_async_enabled
- && linux_nat_async_events_enabled
+ if (target_async_permitted
+ && linux_nat_async_events_state != sigchld_sync
&& signo == SIGCHLD)
/* It is *always* a bug to hit this. */
internal_error (__FILE__, __LINE__,
char permissions[8], device[8], filename[MAXPATHLEN];
int read, write, exec;
int ret;
+ struct cleanup *cleanup;
/* Compose the filename for the /proc memory map, and open it. */
sprintf (mapsfilename, "/proc/%lld/maps", pid);
if ((mapsfile = fopen (mapsfilename, "r")) == NULL)
error (_("Could not open %s."), mapsfilename);
+ cleanup = make_cleanup_fclose (mapsfile);
if (info_verbose)
fprintf_filtered (gdb_stdout,
segment. */
func (addr, size, read, write, exec, obfd);
}
- fclose (mapsfile);
+ do_cleanups (cleanup);
return 0;
}
+static int
+find_signalled_thread (struct thread_info *info, void *data)
+{
+ if (info->stop_signal != TARGET_SIGNAL_0
+ && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
+ return 1;
+
+ return 0;
+}
+
+static enum target_signal
+find_stop_signal (void)
+{
+ struct thread_info *info =
+ iterate_over_threads (find_signalled_thread, NULL);
+
+ if (info)
+ return info->stop_signal;
+ else
+ return TARGET_SIGNAL_0;
+}
+
/* Records the thread's register state for the corefile note
section. */
static char *
linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid,
- char *note_data, int *note_size)
+ char *note_data, int *note_size,
+ enum target_signal stop_signal)
{
gdb_gregset_t gregs;
gdb_fpregset_t fpregs;
-#ifdef FILL_FPXREGSET
- gdb_fpxregset_t fpxregs;
-#endif
unsigned long lwp = ptid_get_lwp (ptid);
struct regcache *regcache = get_thread_regcache (ptid);
struct gdbarch *gdbarch = get_regcache_arch (regcache);
const struct regset *regset;
int core_regset_p;
struct cleanup *old_chain;
+ struct core_regset_section *sect_list;
+ char *gdb_regset;
old_chain = save_inferior_ptid ();
inferior_ptid = ptid;
do_cleanups (old_chain);
core_regset_p = gdbarch_regset_from_core_section_p (gdbarch);
+ sect_list = gdbarch_core_regset_sections (gdbarch);
+
if (core_regset_p
&& (regset = gdbarch_regset_from_core_section (gdbarch, ".reg",
sizeof (gregs))) != NULL
lwp,
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));
+ /* The loop below uses the new struct core_regset_section, which stores
+ the supported section names and sizes for the core file. Note that
+ note PRSTATUS needs to be treated specially. But the other notes are
+ structurally the same, so they can benefit from the new struct. */
+ if (core_regset_p && sect_list != NULL)
+ while (sect_list->sect_name != NULL)
+ {
+ /* .reg was already handled above. */
+ if (strcmp (sect_list->sect_name, ".reg") == 0)
+ {
+ sect_list++;
+ continue;
+ }
+ regset = gdbarch_regset_from_core_section (gdbarch,
+ sect_list->sect_name,
+ sect_list->size);
+ gdb_assert (regset && regset->collect_regset);
+ gdb_regset = xmalloc (sect_list->size);
+ regset->collect_regset (regset, regcache, -1,
+ gdb_regset, sect_list->size);
+ note_data = (char *) elfcore_write_register_note (obfd,
+ note_data,
+ note_size,
+ sect_list->sect_name,
+ gdb_regset,
+ sect_list->size);
+ xfree (gdb_regset);
+ sect_list++;
+ }
-#ifdef FILL_FPXREGSET
- if (core_regset_p
- && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg-xfp",
- sizeof (fpxregs))) != NULL
- && regset->collect_regset != NULL)
- regset->collect_regset (regset, regcache, -1,
- &fpxregs, sizeof (fpxregs));
+ /* For architectures that does not have the struct core_regset_section
+ implemented, we use the old method. When all the architectures have
+ the new support, the code below should be deleted. */
else
- fill_fpxregset (regcache, &fpxregs, -1);
+ {
+ 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));
+ }
- note_data = (char *) elfcore_write_prxfpreg (obfd,
- note_data,
- note_size,
- &fpxregs, sizeof (fpxregs));
-#endif
return note_data;
}
char *note_data;
int *note_size;
int num_notes;
+ enum target_signal stop_signal;
};
/* Called by gdbthread.c once per thread. Records the thread's
args->note_data = linux_nat_do_thread_registers (args->obfd,
ti->ptid,
args->note_data,
- args->note_size);
+ args->note_size,
+ args->stop_signal);
args->num_notes++;
return 0;
}
-/* Records the register state for the corefile note section. */
-
-static char *
-linux_nat_do_registers (bfd *obfd, ptid_t ptid,
- char *note_data, int *note_size)
-{
- return linux_nat_do_thread_registers (obfd,
- ptid_build (ptid_get_pid (inferior_ptid),
- ptid_get_pid (inferior_ptid),
- 0),
- note_data, note_size);
-}
-
/* Fills the "to_make_corefile_note" target vector. Builds the note
section for a corefile, and returns it in a malloc buffer. */
thread_args.note_data = note_data;
thread_args.note_size = note_size;
thread_args.num_notes = 0;
+ thread_args.stop_signal = find_stop_signal ();
iterate_over_lwps (linux_nat_corefile_thread_callback, &thread_args);
- if (thread_args.num_notes == 0)
- {
- /* iterate_over_threads didn't come up with any threads; just
- use inferior_ptid. */
- note_data = linux_nat_do_registers (obfd, inferior_ptid,
- note_data, note_size);
- }
- else
- {
- note_data = thread_args.note_data;
- }
+ gdb_assert (thread_args.num_notes != 0);
+ note_data = thread_args.note_data;
auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV,
NULL, &auxv);
if (args)
{
/* Break up 'args' into an argv array. */
- if ((argv = buildargv (args)) == NULL)
- nomem (0);
- else
- make_cleanup_freeargv (argv);
+ argv = gdb_buildargv (args);
+ make_cleanup_freeargv (argv);
}
while (argv != NULL && *argv != NULL)
{
sprintf (fname1, "/proc/%lld/cmdline", pid);
if ((procfile = fopen (fname1, "r")) != NULL)
{
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
fgets (buffer, sizeof (buffer), procfile);
printf_filtered ("cmdline = '%s'\n", buffer);
- fclose (procfile);
+ do_cleanups (cleanup);
}
else
warning (_("unable to open /proc file '%s'"), fname1);
{
long long addr, endaddr, size, offset, inode;
char permissions[8], device[8], filename[MAXPATHLEN];
+ struct cleanup *cleanup;
+ cleanup = make_cleanup_fclose (procfile);
printf_filtered (_("Mapped address spaces:\n\n"));
if (gdbarch_addr_bit (current_gdbarch) == 32)
{
}
}
- fclose (procfile);
+ do_cleanups (cleanup);
}
else
warning (_("unable to open /proc file '%s'"), fname1);
sprintf (fname1, "/proc/%lld/status", pid);
if ((procfile = fopen (fname1, "r")) != NULL)
{
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
while (fgets (buffer, sizeof (buffer), procfile) != NULL)
puts_filtered (buffer);
- fclose (procfile);
+ do_cleanups (cleanup);
}
else
warning (_("unable to open /proc file '%s'"), fname1);
int itmp;
char ctmp;
long ltmp;
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
if (fscanf (procfile, "%d ", &itmp) > 0)
printf_filtered (_("Process: %d\n"), itmp);
if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp);
#endif
- fclose (procfile);
+ do_cleanups (cleanup);
}
else
warning (_("unable to open /proc file '%s'"), fname1);
FILE *procfile;
char buffer[MAXPATHLEN], fname[MAXPATHLEN];
int signum;
+ struct cleanup *cleanup;
sigemptyset (pending);
sigemptyset (blocked);
procfile = fopen (fname, "r");
if (procfile == NULL)
error (_("Could not open %s"), fname);
+ cleanup = make_cleanup_fclose (procfile);
while (fgets (buffer, MAXPATHLEN, procfile) != NULL)
{
add_line_to_sigset (buffer + 8, ignored);
}
- fclose (procfile);
+ do_cleanups (cleanup);
+}
+
+static LONGEST
+linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
+{
+ /* We make the process list snapshot when the object starts to be
+ read. */
+ static const char *buf;
+ static LONGEST len_avail = -1;
+ static struct obstack obstack;
+
+ DIR *dirp;
+
+ gdb_assert (object == TARGET_OBJECT_OSDATA);
+
+ if (strcmp (annex, "processes") != 0)
+ return 0;
+
+ gdb_assert (readbuf && !writebuf);
+
+ if (offset == 0)
+ {
+ if (len_avail != -1 && len_avail != 0)
+ obstack_free (&obstack, NULL);
+ len_avail = 0;
+ buf = NULL;
+ obstack_init (&obstack);
+ obstack_grow_str (&obstack, "<osdata type=\"processes\">\n");
+
+ dirp = opendir ("/proc");
+ if (dirp)
+ {
+ struct dirent *dp;
+ while ((dp = readdir (dirp)) != NULL)
+ {
+ struct stat statbuf;
+ char procentry[sizeof ("/proc/4294967295")];
+
+ if (!isdigit (dp->d_name[0])
+ || strlen (dp->d_name) > sizeof ("4294967295") - 1)
+ continue;
+
+ sprintf (procentry, "/proc/%s", dp->d_name);
+ if (stat (procentry, &statbuf) == 0
+ && S_ISDIR (statbuf.st_mode))
+ {
+ char *pathname;
+ FILE *f;
+ char cmd[MAXPATHLEN + 1];
+ struct passwd *entry;
+
+ pathname = xstrprintf ("/proc/%s/cmdline", dp->d_name);
+ entry = getpwuid (statbuf.st_uid);
+
+ if ((f = fopen (pathname, "r")) != NULL)
+ {
+ size_t len = fread (cmd, 1, sizeof (cmd) - 1, f);
+ if (len > 0)
+ {
+ int i;
+ for (i = 0; i < len; i++)
+ if (cmd[i] == '\0')
+ cmd[i] = ' ';
+ cmd[len] = '\0';
+
+ obstack_xml_printf (
+ &obstack,
+ "<item>"
+ "<column name=\"pid\">%s</column>"
+ "<column name=\"user\">%s</column>"
+ "<column name=\"command\">%s</column>"
+ "</item>",
+ dp->d_name,
+ entry ? entry->pw_name : "?",
+ cmd);
+ }
+ fclose (f);
+ }
+
+ xfree (pathname);
+ }
+ }
+
+ closedir (dirp);
+ }
+
+ obstack_grow_str0 (&obstack, "</osdata>\n");
+ buf = obstack_finish (&obstack);
+ len_avail = strlen (buf);
+ }
+
+ if (offset >= len_avail)
+ {
+ /* Done. Get rid of the obstack. */
+ obstack_free (&obstack, NULL);
+ buf = NULL;
+ len_avail = 0;
+ return 0;
+ }
+
+ if (len > len_avail - offset)
+ len = len_avail - offset;
+ memcpy (readbuf, buf + offset, len);
+
+ return len;
}
static LONGEST
return procfs_xfer_auxv (ops, object, annex, readbuf, writebuf,
offset, len);
+ if (object == TARGET_OBJECT_OSDATA)
+ return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf,
offset, len);
if (xfer != 0)
return t;
}
-/* Controls if async mode is permitted. */
-static int linux_async_permitted = 0;
-
-/* The set command writes to this variable. If the inferior is
- executing, linux_nat_async_permitted is *not* updated. */
-static int linux_async_permitted_1 = 0;
-
-static void
-set_maintenance_linux_async_permitted (char *args, int from_tty,
- struct cmd_list_element *c)
-{
- if (target_has_execution)
- {
- linux_async_permitted_1 = linux_async_permitted;
- error (_("Cannot change this setting while the inferior is running."));
- }
-
- linux_async_permitted = linux_async_permitted_1;
- linux_nat_set_async_mode (linux_async_permitted);
-}
-
-static void
-show_maintenance_linux_async_permitted (struct ui_file *file, int from_tty,
- struct cmd_list_element *c, const char *value)
-{
- fprintf_filtered (file, _("\
-Controlling the GNU/Linux inferior in asynchronous mode is %s.\n"),
- value);
-}
-
/* target_is_async_p implementation. */
static int
linux_nat_is_async_p (void)
{
/* NOTE: palves 2008-03-21: We're only async when the user requests
- it explicitly with the "maintenance set linux-async" command.
+ it explicitly with the "maintenance set target-async" command.
Someday, linux will always be async. */
- if (!linux_async_permitted)
+ if (!target_async_permitted)
return 0;
return 1;
linux_nat_can_async_p (void)
{
/* NOTE: palves 2008-03-21: We're only async when the user requests
- it explicitly with the "maintenance set linux-async" command.
+ it explicitly with the "maintenance set target-async" command.
Someday, linux will always be async. */
- if (!linux_async_permitted)
+ if (!target_async_permitted)
return 0;
/* See target.h/target_async_mask. */
return linux_nat_async_mask_value;
}
+static int
+linux_nat_supports_non_stop (void)
+{
+ return 1;
+}
+
/* target_async_mask implementation. */
static int
{
linux_nat_async (NULL, 0);
linux_nat_async_mask_value = mask;
- /* We're in sync mode. Make sure SIGCHLD isn't handled by
- async_sigchld_handler when we come out of sigsuspend in
- linux_nat_wait. */
- sigaction (SIGCHLD, &sync_sigchld_action, NULL);
}
else
{
- /* Restore the async handler. */
- sigaction (SIGCHLD, &async_sigchld_action, NULL);
linux_nat_async_mask_value = mask;
linux_nat_async (inferior_event_handler, 0);
}
{
int status, options, pid;
- if (!linux_nat_async_enabled || !linux_nat_async_events_enabled)
+ if (!target_async_permitted
+ || linux_nat_async_events_state != sigchld_async)
internal_error (__FILE__, __LINE__,
"get_pending_events called with async masked");
get_pending_events ();
}
-/* Enable or disable async SIGCHLD handling. */
+/* Set SIGCHLD handling state to STATE. Returns previous state. */
-static int
-linux_nat_async_events (int enable)
+static enum sigchld_state
+linux_nat_async_events (enum sigchld_state state)
{
- int current_state = linux_nat_async_events_enabled;
+ enum sigchld_state current_state = linux_nat_async_events_state;
if (debug_linux_nat_async)
fprintf_unfiltered (gdb_stdlog,
- "LNAE: enable(%d): linux_nat_async_events_enabled(%d), "
+ "LNAE: state(%d): linux_nat_async_events_state(%d), "
"linux_nat_num_queued_events(%d)\n",
- enable, linux_nat_async_events_enabled,
+ state, linux_nat_async_events_state,
linux_nat_num_queued_events);
- if (current_state != enable)
+ if (current_state != state)
{
sigset_t mask;
sigemptyset (&mask);
sigaddset (&mask, SIGCHLD);
- if (enable)
- {
- /* Unblock target events. */
- linux_nat_async_events_enabled = 1;
-
- local_event_queue_to_pipe ();
- /* While in masked async, we may have not collected all the
- pending events. Get them out now. */
- get_pending_events ();
- sigprocmask (SIG_UNBLOCK, &mask, NULL);
- }
- else
+
+ /* Always block before changing state. */
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+
+ /* Set new state. */
+ linux_nat_async_events_state = state;
+
+ switch (state)
{
- /* Block target events. */
- sigprocmask (SIG_BLOCK, &mask, NULL);
- linux_nat_async_events_enabled = 0;
- /* Get events out of queue, and make them available to
- queued_waitpid / my_waitpid. */
- pipe_to_local_event_queue ();
+ case sigchld_sync:
+ {
+ /* Block target events. */
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
+ /* Get events out of queue, and make them available to
+ queued_waitpid / my_waitpid. */
+ pipe_to_local_event_queue ();
+ }
+ break;
+ case sigchld_async:
+ {
+ /* Unblock target events for async mode. */
+
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+
+ /* Put events we already waited on, in the pipe first, so
+ events are FIFO. */
+ local_event_queue_to_pipe ();
+ /* While in masked async, we may have not collected all
+ the pending events. Get them out now. */
+ get_pending_events ();
+
+ /* Let'em come. */
+ sigaction (SIGCHLD, &async_sigchld_action, NULL);
+ sigprocmask (SIG_UNBLOCK, &mask, NULL);
+ }
+ break;
+ case sigchld_default:
+ {
+ /* SIGCHLD default mode. */
+ sigaction (SIGCHLD, &sigchld_default_action, NULL);
+
+ /* Get events out of queue, and make them available to
+ queued_waitpid / my_waitpid. */
+ pipe_to_local_event_queue ();
+
+ /* Unblock SIGCHLD. */
+ sigprocmask (SIG_UNBLOCK, &mask, NULL);
+ }
+ break;
}
}
linux_nat_async (void (*callback) (enum inferior_event_type event_type,
void *context), void *context)
{
- if (linux_nat_async_mask_value == 0 || !linux_nat_async_enabled)
+ if (linux_nat_async_mask_value == 0 || !target_async_permitted)
internal_error (__FILE__, __LINE__,
"Calling target_async when async is masked");
add_file_handler (linux_nat_event_pipe[0],
linux_nat_async_file_handler, NULL);
- linux_nat_async_events (1);
+ linux_nat_async_events (sigchld_async);
}
else
{
async_client_callback = callback;
async_client_context = context;
- linux_nat_async_events (0);
+ linux_nat_async_events (sigchld_sync);
delete_file_handler (linux_nat_event_pipe[0]);
}
return;
}
-/* Enable/Disable async mode. */
+/* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
+ event came out. */
-static void
-linux_nat_set_async_mode (int on)
+static int
+linux_nat_stop_lwp (struct lwp_info *lwp, void *data)
{
- if (linux_nat_async_enabled != on)
+ ptid_t ptid = * (ptid_t *) data;
+
+ if (ptid_equal (lwp->ptid, ptid)
+ || ptid_equal (minus_one_ptid, ptid)
+ || (ptid_is_pid (ptid)
+ && ptid_get_pid (ptid) == ptid_get_pid (lwp->ptid)))
{
- if (on)
+ if (!lwp->stopped)
{
- gdb_assert (waitpid_queue == NULL);
- sigaction (SIGCHLD, &async_sigchld_action, NULL);
+ int pid, status;
- if (pipe (linux_nat_event_pipe) == -1)
- internal_error (__FILE__, __LINE__,
- "creating event pipe failed.");
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNSL: running -> suspending %s\n",
+ target_pid_to_str (lwp->ptid));
+
+ /* Peek once, to check if we've already waited for this
+ LWP. */
+ pid = queued_waitpid_1 (ptid_get_lwp (lwp->ptid), &status,
+ lwp->cloned ? __WCLONE : 0, 1 /* peek */);
+
+ if (pid == -1)
+ {
+ ptid_t ptid = lwp->ptid;
+
+ stop_callback (lwp, NULL);
+ stop_wait_callback (lwp, NULL);
- fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK);
- fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK);
+ /* If the lwp exits while we try to stop it, there's
+ nothing else to do. */
+ lwp = find_lwp_pid (ptid);
+ if (lwp == NULL)
+ return 0;
+
+ pid = queued_waitpid_1 (ptid_get_lwp (lwp->ptid), &status,
+ lwp->cloned ? __WCLONE : 0,
+ 1 /* peek */);
+ }
+
+ /* If we didn't collect any signal other than SIGSTOP while
+ stopping the LWP, push a SIGNAL_0 event. In either case,
+ the event-loop will end up calling target_wait which will
+ collect these. */
+ if (pid == -1)
+ push_waitpid (ptid_get_lwp (lwp->ptid), W_STOPCODE (0),
+ lwp->cloned ? __WCLONE : 0);
}
else
{
- sigaction (SIGCHLD, &sync_sigchld_action, NULL);
-
- drain_queued_events (-1);
-
- linux_nat_num_queued_events = 0;
- close (linux_nat_event_pipe[0]);
- close (linux_nat_event_pipe[1]);
- linux_nat_event_pipe[0] = linux_nat_event_pipe[1] = -1;
+ /* Already known to be stopped; do nothing. */
+ if (debug_linux_nat)
+ {
+ if (find_thread_pid (lwp->ptid)->stop_requested)
+ fprintf_unfiltered (gdb_stdlog, "\
+LNSL: already stopped/stop_requested %s\n",
+ target_pid_to_str (lwp->ptid));
+ else
+ fprintf_unfiltered (gdb_stdlog, "\
+LNSL: already stopped/no stop_requested yet %s\n",
+ target_pid_to_str (lwp->ptid));
+ }
}
}
- linux_nat_async_enabled = on;
+ return 0;
+}
+
+static void
+linux_nat_stop (ptid_t ptid)
+{
+ if (non_stop)
+ {
+ linux_nat_async_events (sigchld_sync);
+ iterate_over_lwps (linux_nat_stop_lwp, &ptid);
+ target_async (inferior_event_handler, 0);
+ }
+ else
+ linux_ops->to_stop (ptid);
}
void
t->to_can_async_p = linux_nat_can_async_p;
t->to_is_async_p = linux_nat_is_async_p;
+ t->to_supports_non_stop = linux_nat_supports_non_stop;
t->to_async = linux_nat_async;
t->to_async_mask = linux_nat_async_mask;
t->to_terminal_inferior = linux_nat_terminal_inferior;
t->to_terminal_ours = linux_nat_terminal_ours;
+ /* Methods for non-stop support. */
+ t->to_stop = linux_nat_stop;
+
/* We don't change the stratum; this target will sit at
process_stratum and thread_db will set at thread_stratum. This
is a little strange, since this is a multi-threaded-capable
return &lp->siginfo;
}
+/* Enable/Disable async mode. */
+
+static void
+linux_nat_setup_async (void)
+{
+ if (pipe (linux_nat_event_pipe) == -1)
+ internal_error (__FILE__, __LINE__,
+ "creating event pipe failed.");
+ fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK);
+ fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK);
+}
+
void
_initialize_linux_nat (void)
{
show_debug_linux_nat_async,
&setdebuglist, &showdebuglist);
- add_setshow_boolean_cmd ("linux-async", class_maintenance,
- &linux_async_permitted_1, _("\
-Set whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\
-Show whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\
-Tells gdb whether to control the GNU/Linux inferior in asynchronous mode."),
- set_maintenance_linux_async_permitted,
- show_maintenance_linux_async_permitted,
- &maintenance_set_cmdlist,
- &maintenance_show_cmdlist);
+ /* Get the default SIGCHLD action. Used while forking an inferior
+ (see linux_nat_create_inferior/linux_nat_async_events). */
+ sigaction (SIGCHLD, NULL, &sigchld_default_action);
/* Block SIGCHLD by default. Doing this early prevents it getting
unblocked if an exception is thrown due to an error while the
sigemptyset (&async_sigchld_action.sa_mask);
async_sigchld_action.sa_flags = SA_RESTART;
- /* Install the default mode. */
- linux_nat_set_async_mode (linux_async_permitted);
+ linux_nat_setup_async ();
+
+ add_setshow_boolean_cmd ("disable-randomization", class_support,
+ &disable_randomization, _("\
+Set disabling of debuggee's virtual address space randomization."), _("\
+Show disabling of debuggee's virtual address space randomization."), _("\
+When this mode is on (which is the default), randomization of the virtual\n\
+address space is disabled. Standalone programs run with the randomization\n\
+enabled by default on some platforms."),
+ &set_disable_randomization,
+ &show_disable_randomization,
+ &setlist, &showlist);
}
\f
projects / deliverable / binutils-gdb.git / blobdiff