/* GNU/Linux native-dependent code common to multiple platforms.
- Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "inferior.h"
#include "gdbthread.h" /* for struct thread_info etc. */
#include "gdb_stat.h" /* for struct stat */
#include <fcntl.h> /* for O_RDONLY */
+#include "inf-loop.h"
+#include "event-loop.h"
+#include "event-top.h"
+#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
#define __WALL 0x40000000 /* Wait for any child. */
#endif
+#ifndef PTRACE_GETSIGINFO
+#define PTRACE_GETSIGINFO 0x4202
+#endif
+
/* The single-threaded native GNU/Linux target_ops. We save a pointer for
the use of the multi-threaded target. */
static struct target_ops *linux_ops;
static struct target_ops linux_ops_saved;
+/* The method to call, if any, when a new thread is attached. */
+static void (*linux_nat_new_thread) (ptid_t);
+
/* The saved to_xfer_partial method, inherited from inf-ptrace.c.
Called by our to_xfer_partial. */
static LONGEST (*super_xfer_partial) (struct target_ops *,
value);
}
+static int debug_linux_nat_async = 0;
+static void
+show_debug_linux_nat_async (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("Debugging of GNU/Linux async lwp module is %s.\n"),
+ 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
static int linux_supports_tracevforkdone_flag = -1;
+/* Async mode support */
+
+/* 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;
+
+/* The read/write ends of the pipe registered as waitable file in the
+ event loop. */
+static int linux_nat_event_pipe[2] = { -1, -1 };
+
+/* Number of queued events in the pipe. */
+static volatile int linux_nat_num_queued_events;
+
+/* The possible SIGCHLD handling states. */
+
+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_event_pipe_pop (int* ptr_status, int* ptr_options);
+static void linux_nat_set_async_mode (int on);
+static void linux_nat_async (void (*callback)
+ (enum inferior_event_type event_type, void *context),
+ void *context);
+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
+{
+ int pid;
+ int status;
+ int options;
+ struct waitpid_result *next;
+};
+
+/* A singly-linked list of the results of the waitpid calls performed
+ 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_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_state(%d), linux_nat_num_queued_events(%d)\n",
+ linux_nat_async_events_state,
+ linux_nat_num_queued_events);
+
+ if (flags & __WALL)
+ {
+ for (; msg; prev = msg, msg = msg->next)
+ if (pid == -1 || pid == msg->pid)
+ break;
+ }
+ else if (flags & __WCLONE)
+ {
+ for (; msg; prev = msg, msg = msg->next)
+ if (msg->options & __WCLONE
+ && (pid == -1 || pid == msg->pid))
+ break;
+ }
+ else
+ {
+ for (; msg; prev = msg, msg = msg->next)
+ if ((msg->options & __WCLONE) == 0
+ && (pid == -1 || pid == msg->pid))
+ break;
+ }
+
+ if (msg)
+ {
+ int pid;
+
+ 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);
+
+ if (!peek)
+ {
+ if (prev)
+ prev->next = msg->next;
+ else
+ waitpid_queue = msg->next;
+
+ msg->next = NULL;
+ xfree (msg);
+ }
+
+ return pid;
+ }
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "QWPID: miss\n");
+
+ if (status)
+ *status = 0;
+ 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)
+{
+ struct waitpid_result *event, *new_event;
+
+ new_event = xmalloc (sizeof (*new_event));
+ new_event->pid = pid;
+ new_event->status = status;
+ new_event->options = options;
+ new_event->next = NULL;
+
+ if (waitpid_queue)
+ {
+ for (event = waitpid_queue;
+ event && event->next;
+ event = event->next)
+ ;
+
+ event->next = new_event;
+ }
+ else
+ waitpid_queue = new_event;
+}
+
+/* Drain all queued events of PID. If PID is -1, the effect is of
+ draining all events. */
+static void
+drain_queued_events (int pid)
+{
+ while (queued_waitpid (pid, NULL, __WALL) != -1)
+ ;
+}
+
\f
/* Trivial list manipulation functions to keep track of a list of
new stopped processes. */
_exit (0);
}
-/* Wrapper function for waitpid which handles EINTR. */
+/* Wrapper function for waitpid which handles EINTR, and checks for
+ locally queued events. */
static int
my_waitpid (int pid, int *status, int flags)
{
int ret;
+
+ /* There should be no concurrent calls to waitpid. */
+ gdb_assert (linux_nat_async_events_state == sigchld_sync);
+
+ ret = queued_waitpid (pid, status, flags);
+ if (ret != -1)
+ return ret;
+
do
{
ret = waitpid (pid, status, flags);
{
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.
int has_vforked;
int parent_pid, child_pid;
+ if (target_can_async_p ())
+ target_async (NULL, 0);
+
get_last_target_status (&last_ptid, &last_status);
has_vforked = (last_status.kind == TARGET_WAITKIND_VFORKED);
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)
{
/* Detach new forked process? */
if (detach_fork)
{
- if (debug_linux_nat)
+ if (info_verbose || debug_linux_nat)
{
target_terminal_ours ();
fprintf_filtered (gdb_stdlog,
else
{
struct fork_info *fp;
+ struct inferior *parent_inf, *child_inf;
+
+ /* Add process to GDB's tables. */
+ child_inf = add_inferior (child_pid);
+
+ parent_inf = find_inferior_pid (GET_PID (last_ptid));
+ child_inf->attach_flag = parent_inf->attach_flag;
+
/* 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];
+ struct inferior *parent_inf, *child_inf;
+
+ /* 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)
/* Before detaching from the parent, remove all breakpoints from it. */
remove_breakpoints ();
- if (debug_linux_nat)
+ if (info_verbose || debug_linux_nat)
{
target_terminal_ours ();
fprintf_filtered (gdb_stdlog,
child_pid);
}
+ /* Add the new inferior first, so that the target_detach below
+ doesn't unpush the target. */
+
+ child_inf = add_inferior (child_pid);
+
+ parent_inf = find_inferior_pid (GET_PID (last_ptid));
+ child_inf->attach_flag = parent_inf->attach_flag;
+
/* If we're vforking, we may want to hold on to the parent until
the child exits or execs. At exec time we can remove the old
breakpoints from the parent and detach it; at exit time we
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;
if (!fp)
fp = add_fork (parent_pid);
fork_save_infrun_state (fp, 0);
+
+ /* Also add an entry for the child fork. */
+ fp = find_fork_pid (child_pid);
+ if (!fp)
+ fp = add_fork (child_pid);
+ fork_save_infrun_state (fp, 0);
}
else
- {
- target_detach (NULL, 0);
- }
+ target_detach (NULL, 0);
- inferior_ptid = pid_to_ptid (child_pid);
+ inferior_ptid = ptid_build (child_pid, child_pid, 0);
- /* 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 ();
- push_target (ops);
+ 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 ();
}
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+
return 0;
}
because the "zombies" stay around. */
/* List of known LWPs. */
-static struct lwp_info *lwp_list;
+struct lwp_info *lwp_list;
/* Number of LWPs in the list. */
static int num_lwps;
\f
-#define GET_LWP(ptid) ptid_get_lwp (ptid)
-#define GET_PID(ptid) ptid_get_pid (ptid)
-#define is_lwp(ptid) (GET_LWP (ptid) != 0)
-#define BUILD_LWP(lwp, pid) ptid_build (pid, lwp, 0)
-
-/* 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;
_initialize_linux_nat. */
static sigset_t suspend_mask;
-/* Signals to block to make that sigsuspend work. */
-static sigset_t blocked_mask;
+/* SIGCHLD action for synchronous mode. */
+struct sigaction sync_sigchld_action;
+
+/* 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. */
static int stop_wait_callback (struct lwp_info *lp, void *data);
static int linux_nat_thread_alive (ptid_t ptid);
static char *linux_child_pid_to_exec_file (int pid);
+static int cancel_breakpoint (struct lwp_info *lp);
+
\f
/* Convert wait status STATUS to a string. Used for printing debug
messages only. */
}
/* Add the LWP specified by PID to the list. Return a pointer to the
- structure describing the new LWP. */
+ structure describing the new LWP. The LWP should already be stopped
+ (with an exception for the very first LWP). */
static struct lwp_info *
add_lwp (ptid_t ptid)
lwp_list = lp;
++num_lwps;
+ if (num_lwps > 1 && linux_nat_new_thread != NULL)
+ linux_nat_new_thread (ptid);
+
return lp;
}
init_lwp_list ();
lp = add_lwp (new_ptid);
lp->stopped = 1;
-}
-/* Record a PTID for later deletion. */
+ init_thread_list ();
+ add_thread_silent (new_ptid);
+}
-struct saved_ptids
-{
- ptid_t ptid;
- struct saved_ptids *next;
-};
-static struct saved_ptids *threads_to_delete;
+/* Handle the exit of a single thread LP. */
static void
-record_dead_thread (ptid_t ptid)
+exit_lwp (struct lwp_info *lp)
{
- struct saved_ptids *p = xmalloc (sizeof (struct saved_ptids));
- p->ptid = ptid;
- p->next = threads_to_delete;
- threads_to_delete = p;
-}
+ struct thread_info *th = find_thread_pid (lp->ptid);
-/* Delete any dead threads which are not the current thread. */
+ if (th)
+ {
+ if (print_thread_events)
+ printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid));
-static void
-prune_lwps (void)
-{
- struct saved_ptids **p = &threads_to_delete;
+ delete_thread (lp->ptid);
+ }
- 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;
+ delete_lwp (lp->ptid);
}
-/* Callback for iterate_over_threads that finds a thread corresponding
- to the given LWP. */
+/* Detect `T (stopped)' in `/proc/PID/status'.
+ Other states including `T (tracing stop)' are reported as false. */
static int
-find_thread_from_lwp (struct thread_info *thr, void *dummy)
+pid_is_stopped (pid_t pid)
{
- ptid_t *ptid_p = dummy;
+ FILE *status_file;
+ char buf[100];
+ int retval = 0;
- if (GET_LWP (thr->ptid) && GET_LWP (thr->ptid) == GET_LWP (*ptid_p))
- return 1;
- else
- return 0;
+ snprintf (buf, sizeof (buf), "/proc/%d/status", (int) pid);
+ status_file = fopen (buf, "r");
+ if (status_file != NULL)
+ {
+ int have_state = 0;
+
+ while (fgets (buf, sizeof (buf), status_file))
+ {
+ if (strncmp (buf, "State:", 6) == 0)
+ {
+ have_state = 1;
+ break;
+ }
+ }
+ if (have_state && strstr (buf, "T (stopped)") != NULL)
+ retval = 1;
+ fclose (status_file);
+ }
+ return retval;
}
-/* Handle the exit of a single thread LP. */
+/* Wait for the LWP specified by LP, which we have just attached to.
+ Returns a wait status for that LWP, to cache. */
-static void
-exit_lwp (struct lwp_info *lp)
+static int
+linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned,
+ int *signalled)
{
- if (in_thread_list (lp->ptid))
+ pid_t new_pid, pid = GET_LWP (ptid);
+ int status;
+
+ if (pid_is_stopped (pid))
{
- /* 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);
- printf_unfiltered (_("[%s exited]\n"),
- target_pid_to_str (lp->ptid));
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNPAW: Attaching to a stopped process\n");
+
+ /* The process is definitely stopped. It is in a job control
+ stop, unless the kernel predates the TASK_STOPPED /
+ TASK_TRACED distinction, in which case it might be in a
+ ptrace stop. Make sure it is in a ptrace stop; from there we
+ can kill it, signal it, et cetera.
+
+ First make sure there is a pending SIGSTOP. Since we are
+ already attached, the process can not transition from stopped
+ to running without a PTRACE_CONT; so we know this signal will
+ go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
+ probably already in the queue (unless this kernel is old
+ enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP
+ is not an RT signal, it can only be queued once. */
+ kill_lwp (pid, SIGSTOP);
+
+ /* Finally, resume the stopped process. This will deliver the SIGSTOP
+ (or a higher priority signal, just like normal PTRACE_ATTACH). */
+ ptrace (PTRACE_CONT, pid, 0, 0);
}
- else
+
+ /* Make sure the initial process is stopped. The user-level threads
+ layer might want to poke around in the inferior, and that won't
+ work if things haven't stabilized yet. */
+ new_pid = my_waitpid (pid, &status, 0);
+ if (new_pid == -1 && errno == ECHILD)
{
- /* Even if LP->PTID is not in the global GDB thread list, the
- LWP may be - with an additional thread ID. We don't need
- to print anything in this case; thread_db is in use and
- already took care of that. But it didn't delete the thread
- in order to handle zombies correctly. */
+ if (first)
+ warning (_("%s is a cloned process"), target_pid_to_str (ptid));
- struct thread_info *thr;
+ /* Try again with __WCLONE to check cloned processes. */
+ new_pid = my_waitpid (pid, &status, __WCLONE);
+ *cloned = 1;
+ }
- thr = iterate_over_threads (find_thread_from_lwp, &lp->ptid);
- if (thr)
- {
- if (!ptid_equal (thr->ptid, inferior_ptid))
- delete_thread (thr->ptid);
- else
- record_dead_thread (thr->ptid);
- }
+ gdb_assert (pid == new_pid && WIFSTOPPED (status));
+
+ if (WSTOPSIG (status) != SIGSTOP)
+ {
+ *signalled = 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNPAW: Received %s after attaching\n",
+ status_to_str (status));
}
- delete_lwp (lp->ptid);
+ return status;
}
-/* Attach to the LWP specified by PID. If VERBOSE is non-zero, print
- a message telling the user that a new LWP has been added to the
- process. Return 0 if successful or -1 if the new LWP could not
- be attached. */
+/* Attach to the LWP specified by PID. Return 0 if successful or -1
+ if the new LWP could not be attached. */
int
-lin_lwp_attach_lwp (ptid_t ptid, int verbose)
+lin_lwp_attach_lwp (ptid_t ptid)
{
struct lwp_info *lp;
+ enum sigchld_state async_events_original_state;
gdb_assert (is_lwp (ptid));
- /* Make sure SIGCHLD is blocked. We don't want SIGCHLD events
- to interrupt either the ptrace() or waitpid() calls below. */
- if (!sigismember (&blocked_mask, SIGCHLD))
- {
- sigaddset (&blocked_mask, SIGCHLD);
- sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
- }
+ async_events_original_state = linux_nat_async_events (sigchld_sync);
lp = find_lwp_pid (ptid);
to happen. */
if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL)
{
- pid_t pid;
- int status;
+ int status, cloned = 0, signalled = 0;
if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
{
/* If we fail to attach to the thread, issue a warning,
but continue. One way this can happen is if thread
- creation is interrupted; as of Linux 2.6.19, a kernel
+ creation is interrupted; as of Linux kernel 2.6.19, a
bug may place threads in the thread list and then fail
to create them. */
warning (_("Can't attach %s: %s"), target_pid_to_str (ptid),
return -1;
}
- if (lp == NULL)
- lp = add_lwp (ptid);
-
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
target_pid_to_str (ptid));
- pid = my_waitpid (GET_LWP (ptid), &status, 0);
- if (pid == -1 && errno == ECHILD)
+ status = linux_nat_post_attach_wait (ptid, 0, &cloned, &signalled);
+ lp = add_lwp (ptid);
+ lp->stopped = 1;
+ lp->cloned = cloned;
+ lp->signalled = signalled;
+ if (WSTOPSIG (status) != SIGSTOP)
{
- /* Try again with __WCLONE to check cloned processes. */
- pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE);
- lp->cloned = 1;
+ lp->resumed = 1;
+ lp->status = status;
}
- gdb_assert (pid == GET_LWP (ptid)
- && WIFSTOPPED (status) && WSTOPSIG (status));
-
- target_post_attach (pid);
-
- lp->stopped = 1;
+ target_post_attach (GET_LWP (lp->ptid));
if (debug_linux_nat)
{
lp->stopped = 1;
}
- if (verbose)
- printf_filtered (_("[New %s]\n"), target_pid_to_str (ptid));
-
+ linux_nat_async_events (async_events_original_state);
return 0;
}
static void
-linux_nat_attach (char *args, int from_tty)
+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
+ {
+ /* Restore the original signal mask. */
+ sigprocmask (SIG_SETMASK, &normal_mask, NULL);
+ /* Make sure we don't block SIGCHLD during a sigsuspend. */
+ suspend_mask = normal_mask;
+ sigdelset (&suspend_mask, SIGCHLD);
+ }
+
+ /* 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 (struct target_ops *ops, char *args, int from_tty)
{
struct lwp_info *lp;
- pid_t pid;
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);
-
- /* 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);
+ linux_ops->to_attach (ops, args, from_tty);
- /* Make sure the initial process is stopped. The user-level threads
- layer might want to poke around in the inferior, and that won't
- work if things haven't stabilized yet. */
- pid = my_waitpid (GET_PID (inferior_ptid), &status, 0);
- if (pid == -1 && errno == ECHILD)
+ if (!target_can_async_p ())
{
- warning (_("%s is a cloned process"), target_pid_to_str (inferior_ptid));
-
- /* Try again with __WCLONE to check cloned processes. */
- pid = my_waitpid (GET_PID (inferior_ptid), &status, __WCLONE);
- lp->cloned = 1;
+ /* Restore the original signal mask. */
+ sigprocmask (SIG_SETMASK, &normal_mask, NULL);
+ /* Make sure we don't block SIGCHLD during a sigsuspend. */
+ suspend_mask = normal_mask;
+ sigdelset (&suspend_mask, SIGCHLD);
}
- gdb_assert (pid == GET_PID (inferior_ptid)
- && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP);
+ /* 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. */
+ lp = add_lwp (ptid);
+ status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned,
+ &lp->signalled);
lp->stopped = 1;
- /* Fake the SIGSTOP that core GDB expects. */
- lp->status = W_STOPCODE (SIGSTOP);
+ /* Save the wait status to report later. */
lp->resumed = 1;
if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNA: waitpid %ld, saving status %s\n",
+ (long) GET_PID (lp->ptid), status_to_str (status));
+
+ if (!target_can_async_p ())
+ lp->status = status;
+ else
{
- fprintf_unfiltered (gdb_stdlog,
- "LLA: waitpid %ld, faking SIGSTOP\n", (long) pid);
+ /* We already waited for this LWP, so put the wait result on the
+ pipe. The event loop will wake up and gets us to handling
+ this event. */
+ linux_nat_event_pipe_push (GET_PID (lp->ptid), status,
+ lp->cloned ? __WCLONE : 0);
+ /* Register in the event loop. */
+ target_async (inferior_event_handler, 0);
}
}
+/* Get pending status of LP. */
static int
-detach_callback (struct lwp_info *lp, void *data)
+get_pending_status (struct lwp_info *lp, int *status)
{
- gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
-
- if (debug_linux_nat && lp->status)
- fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n",
- strsignal (WSTOPSIG (lp->status)),
- target_pid_to_str (lp->ptid));
-
- while (lp->signalled && lp->stopped)
- {
- errno = 0;
- if (ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0,
- WSTOPSIG (lp->status)) < 0)
- error (_("Can't continue %s: %s"), target_pid_to_str (lp->ptid),
- safe_strerror (errno));
+ struct target_waitstatus last;
+ ptid_t last_ptid;
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "DC: PTRACE_CONTINUE (%s, 0, %s) (OK)\n",
- target_pid_to_str (lp->ptid),
- status_to_str (lp->status));
+ get_last_target_status (&last_ptid, &last);
- lp->stopped = 0;
- lp->signalled = 0;
- lp->status = 0;
- /* FIXME drow/2003-08-26: There was a call to stop_wait_callback
- here. But since lp->signalled was cleared above,
- stop_wait_callback didn't do anything; the process was left
- running. Shouldn't we be waiting for it to stop?
- I've removed the call, since stop_wait_callback now does do
- something when called with lp->signalled == 0. */
+ /* If this lwp is the ptid that GDB is processing an event from, the
+ signal will be in stop_signal. Otherwise, in all-stop + sync
+ mode, we may cache pending events in lp->status while trying to
+ stop all threads (see stop_wait_callback). In async mode, the
+ events are always cached in waitpid_queue. */
- gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
- }
+ *status = 0;
- /* We don't actually detach from the LWP that has an id equal to the
- overall process id just yet. */
- if (GET_LWP (lp->ptid) != GET_PID (lp->ptid))
+ if (non_stop)
{
- errno = 0;
- if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0,
- WSTOPSIG (lp->status)) < 0)
- error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid),
- safe_strerror (errno));
-
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "PTRACE_DETACH (%s, %s, 0) (OK)\n",
- target_pid_to_str (lp->ptid),
- strsignal (WSTOPSIG (lp->status)));
+ enum target_signal signo = TARGET_SIGNAL_0;
- delete_lwp (lp->ptid);
- }
+ 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));
- return 0;
+ /* 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 (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 int
+detach_callback (struct lwp_info *lp, void *data)
+{
+ gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
+
+ if (debug_linux_nat && lp->status)
+ fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n",
+ strsignal (WSTOPSIG (lp->status)),
+ target_pid_to_str (lp->ptid));
+
+ /* If there is a pending SIGSTOP, get rid of it. */
+ if (lp->signalled)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "DC: Sending SIGCONT to %s\n",
+ target_pid_to_str (lp->ptid));
+
+ kill_lwp (GET_LWP (lp->ptid), SIGCONT);
+ lp->signalled = 0;
+ }
+
+ /* We don't actually detach from the LWP that has an id equal to the
+ overall process id just yet. */
+ if (GET_LWP (lp->ptid) != GET_PID (lp->ptid))
+ {
+ int status = 0;
+
+ /* Pass on any pending signal for this LWP. */
+ get_pending_status (lp, &status);
+
+ errno = 0;
+ if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0,
+ WSTOPSIG (status)) < 0)
+ error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid),
+ safe_strerror (errno));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "PTRACE_DETACH (%s, %s, 0) (OK)\n",
+ target_pid_to_str (lp->ptid),
+ strsignal (WSTOPSIG (lp->status)));
+
+ delete_lwp (lp->ptid);
+ }
+
+ 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;
+ enum target_signal sig;
+
+ 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. */
gdb_assert (num_lwps == 1);
- trap_ptid = null_ptid;
+ /* Pass on any pending signal for the last LWP. */
+ if ((args == NULL || *args == '\0')
+ && get_pending_status (lwp_list, &status) != -1
+ && WIFSTOPPED (status))
+ {
+ /* Put the signal number in ARGS so that inf_ptrace_detach will
+ pass it along with PTRACE_DETACH. */
+ args = alloca (8);
+ sprintf (args, "%d", (int) WSTOPSIG (status));
+ fprintf_unfiltered (gdb_stdlog,
+ "LND: Sending signal %s to %s\n",
+ args,
+ target_pid_to_str (lwp_list->ptid));
+ }
/* Destroy LWP info; it's no longer valid. */
init_lwp_list ();
- /* Restore the original signal mask. */
- sigprocmask (SIG_SETMASK, &normal_mask, NULL);
- sigemptyset (&blocked_mask);
+ pid = ptid_get_pid (inferior_ptid);
- inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid));
- linux_ops->to_detach (args, from_tty);
+ if (target_can_async_p ())
+ drain_queued_events (pid);
+
+ if (forks_exist_p ())
+ {
+ /* Multi-fork case. The current inferior_ptid is being detached
+ from, but there are other viable forks to debug. Detach from
+ the current fork, and context-switch to the first
+ available. */
+ linux_fork_detach (args, from_tty);
+
+ if (non_stop && target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+ }
+ else
+ linux_ops->to_detach (ops, args, from_tty);
}
/* Resume LP. */
{
if (lp->stopped && lp->status == 0)
{
- struct thread_info *tp;
-
linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
0, TARGET_SIGNAL_0);
if (debug_linux_nat)
target_pid_to_str (lp->ptid));
lp->stopped = 0;
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 (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. */
ptid = inferior_ptid;
lp = find_lwp_pid (ptid);
- if (lp)
- {
- ptid = pid_to_ptid (GET_LWP (lp->ptid));
+ gdb_assert (lp != NULL);
- /* Remember if we're stepping. */
- lp->step = step;
+ /* Convert to something the lower layer understands. */
+ ptid = pid_to_ptid (GET_LWP (lp->ptid));
- /* Mark this LWP as resumed. */
- lp->resumed = 1;
+ /* Remember if we're stepping. */
+ lp->step = step;
- /* If we have a pending wait status for this thread, there is no
- point in resuming the process. But first make sure that
- linux_nat_wait won't preemptively handle the event - we
- should never take this short-circuit if we are going to
- leave LP running, since we have skipped resuming all the
- other threads. This bit of code needs to be synchronized
- with linux_nat_wait. */
+ /* Mark this LWP as resumed. */
+ lp->resumed = 1;
- if (lp->status && WIFSTOPPED (lp->status))
- {
- int saved_signo = target_signal_from_host (WSTOPSIG (lp->status));
+ /* If we have a pending wait status for this thread, there is no
+ point in resuming the process. But first make sure that
+ linux_nat_wait won't preemptively handle the event - we
+ should never take this short-circuit if we are going to
+ leave LP running, since we have skipped resuming all the
+ other threads. This bit of code needs to be synchronized
+ with linux_nat_wait. */
- if (signal_stop_state (saved_signo) == 0
- && signal_print_state (saved_signo) == 0
- && signal_pass_state (saved_signo) == 1)
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLR: Not short circuiting for ignored "
- "status 0x%x\n", lp->status);
-
- /* FIXME: What should we do if we are supposed to continue
- this thread with a signal? */
- gdb_assert (signo == TARGET_SIGNAL_0);
- signo = saved_signo;
- lp->status = 0;
- }
- }
+ /* In async mode, we never have pending wait status. */
+ if (target_can_async_p () && lp->status)
+ internal_error (__FILE__, __LINE__, "Pending status in async mode");
- if (lp->status)
+ if (lp->status && WIFSTOPPED (lp->status))
+ {
+ int saved_signo;
+ struct inferior *inf;
+
+ 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)
{
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Not short circuiting for ignored "
+ "status 0x%x\n", lp->status);
+
/* FIXME: What should we do if we are supposed to continue
this thread with a signal? */
gdb_assert (signo == TARGET_SIGNAL_0);
+ signo = saved_signo;
+ lp->status = 0;
+ }
+ }
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLR: Short circuiting for status 0x%x\n",
- lp->status);
+ if (lp->status)
+ {
+ /* FIXME: What should we do if we are supposed to continue
+ this thread with a signal? */
+ gdb_assert (signo == TARGET_SIGNAL_0);
- return;
- }
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Short circuiting for status 0x%x\n",
+ lp->status);
- /* Mark LWP as not stopped to prevent it from being continued by
- resume_callback. */
- lp->stopped = 0;
+ return;
}
+ /* Mark LWP as not stopped to prevent it from being continued by
+ resume_callback. */
+ lp->stopped = 0;
+
if (resume_all)
iterate_over_lwps (resume_callback, NULL);
linux_ops->to_resume (ptid, step, signo);
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
+
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LLR: %s %s, %s (resume event thread)\n",
step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
target_pid_to_str (ptid),
signo ? strsignal (signo) : "0");
+
+ if (target_can_async_p ())
+ 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 status;
}
+/* Save the most recent siginfo for LP. This is currently only called
+ for SIGTRAP; some ports use the si_addr field for
+ target_stopped_data_address. In the future, it may also be used to
+ restore the siginfo of requeued signals. */
+
+static void
+save_siginfo (struct lwp_info *lp)
+{
+ errno = 0;
+ ptrace (PTRACE_GETSIGINFO, GET_LWP (lp->ptid),
+ (PTRACE_TYPE_ARG3) 0, &lp->siginfo);
+
+ if (errno != 0)
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
+}
+
/* Send a SIGSTOP to LP. */
static int
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 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)
{
- sigset_t *flush_mask = data;
+ 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)
user will delete or disable the breakpoint, but the
thread will have already tripped on it. */
+ /* Save the trap's siginfo in case we need it later. */
+ save_siginfo (lp);
+
/* Now resume this LWP and get the SIGSTOP event. */
errno = 0;
ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
"SWC: Candidate SIGTRAP event in %s\n",
target_pid_to_str (lp->ptid));
}
- /* Hold the SIGTRAP for handling by linux_nat_wait. */
- stop_wait_callback (lp, data);
- /* If there's another event, throw it back into the queue. */
- if (lp->status)
+ /* 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, NULL);
+
+ if (target_can_async_p ())
{
- if (debug_linux_nat)
+ /* Don't leave a pending wait status in async mode.
+ Retrigger the breakpoint. */
+ if (!cancel_breakpoint (lp))
{
- fprintf_unfiltered (gdb_stdlog,
- "SWC: kill %s, %s\n",
- target_pid_to_str (lp->ptid),
- status_to_str ((int) status));
+ /* There was no gdb breakpoint set at pc. Put
+ the event back in the queue. */
+ if (debug_linux_nat)
+ 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 the SIGTRAP for handling by
+ linux_nat_wait. */
+ /* If there's another event, throw it back into the
+ queue. */
+ if (lp->status)
+ {
+ 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 (lp->status));
}
- kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status));
+ /* Save the sigtrap event. */
+ lp->status = status;
}
- /* Save the sigtrap event. */
- lp->status = status;
return 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);
- /* If the lp->status field is still empty, use it to hold
- this event. If not, then this event must be returned
- to the event queue of the LWP. */
- if (lp->status == 0)
- lp->status = status;
- else
+ 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
+ returned to the event queue of the LWP. */
+ if (lp->status || target_can_async_p ())
{
if (debug_linux_nat)
{
}
kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
}
+ else
+ lp->status = status;
return 0;
}
}
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;
}
static int
-cancel_breakpoints_callback (struct lwp_info *lp, void *data)
+cancel_breakpoint (struct lwp_info *lp)
{
- struct lwp_info *event_lp = data;
-
- /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
- if (lp == event_lp)
- return 0;
-
- /* If a LWP other than the LWP that we're reporting an event for has
- hit a GDB breakpoint (as opposed to some random trap signal),
- then just arrange for it to hit it again later. We don't keep
+ /* Arrange for a breakpoint to be hit again later. We don't keep
the SIGTRAP status and don't forward the SIGTRAP signal to the
LWP. We will handle the current event, eventually we will resume
- all LWPs, and this one will get its breakpoint trap again.
+ this LWP, and this breakpoint will trap again.
If we do not do this, then we run the risk that the user will
delete or disable the breakpoint, but the LWP will have already
tripped on it. */
- if (lp->status != 0
- && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP
- && breakpoint_inserted_here_p (read_pc_pid (lp->ptid) -
- gdbarch_decr_pc_after_break
- (current_gdbarch)))
+ struct regcache *regcache = get_thread_regcache (lp->ptid);
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ CORE_ADDR pc;
+
+ pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch);
+ if (breakpoint_inserted_here_p (pc))
{
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
- "CBC: Push back breakpoint for %s\n",
+ "CB: Push back breakpoint for %s\n",
target_pid_to_str (lp->ptid));
/* Back up the PC if necessary. */
- if (gdbarch_decr_pc_after_break (current_gdbarch))
- write_pc_pid (read_pc_pid (lp->ptid) - gdbarch_decr_pc_after_break
- (current_gdbarch),
- lp->ptid);
+ if (gdbarch_decr_pc_after_break (gdbarch))
+ regcache_write_pc (regcache, pc);
- /* Throw away the SIGTRAP. */
- lp->status = 0;
+ return 1;
}
-
+ return 0;
+}
+
+static int
+cancel_breakpoints_callback (struct lwp_info *lp, void *data)
+{
+ struct lwp_info *event_lp = data;
+
+ /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
+ if (lp == event_lp)
+ return 0;
+
+ /* If a LWP other than the LWP that we're reporting an event for has
+ hit a GDB breakpoint (as opposed to some random trap signal),
+ then just arrange for it to hit it again later. We don't keep
+ the SIGTRAP status and don't forward the SIGTRAP signal to the
+ LWP. We will handle the current event, eventually we will resume
+ all LWPs, and this one will get its breakpoint trap again.
+
+ If we do not do this, then we run the risk that the user will
+ delete or disable the breakpoint, but the LWP will have already
+ tripped on it. */
+
+ if (lp->status != 0
+ && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP
+ && cancel_breakpoint (lp))
+ /* Throw away the SIGTRAP. */
+ lp->status = 0;
+
return 0;
}
return 0;
}
+/* Check if we should go on and pass this event to common code.
+ Return the affected lwp if we are, or NULL otherwise. */
+static struct lwp_info *
+linux_nat_filter_event (int lwpid, int status, int options)
+{
+ struct lwp_info *lp;
+
+ lp = find_lwp_pid (pid_to_ptid (lwpid));
+
+ /* Check for stop events reported by a process we didn't already
+ know about - anything not already in our LWP list.
+
+ If we're expecting to receive stopped processes after
+ fork, vfork, and clone events, then we'll just add the
+ new one to our list and go back to waiting for the event
+ to be reported - the stopped process might be returned
+ from waitpid before or after the event is. */
+ if (WIFSTOPPED (status) && !lp)
+ {
+ linux_record_stopped_pid (lwpid, status);
+ return NULL;
+ }
+
+ /* Make sure we don't report an event for the exit of an LWP not in
+ our list, i.e. not part of the current process. This can happen
+ if we detach from a program we original forked and then it
+ exits. */
+ if (!WIFSTOPPED (status) && !lp)
+ return NULL;
+
+ /* NOTE drow/2003-06-17: This code seems to be meant for debugging
+ CLONE_PTRACE processes which do not use the thread library -
+ otherwise we wouldn't find the new LWP this way. That doesn't
+ currently work, and the following code is currently unreachable
+ due to the two blocks above. If it's fixed some day, this code
+ should be broken out into a function so that we can also pick up
+ LWPs from the new interface. */
+ if (!lp)
+ {
+ lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
+ if (options & __WCLONE)
+ lp->cloned = 1;
+
+ gdb_assert (WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGSTOP);
+ lp->signalled = 1;
+
+ if (!in_thread_list (inferior_ptid))
+ {
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ add_thread (inferior_ptid);
+ }
+
+ add_thread (lp->ptid);
+ }
+
+ /* Save the trap's siginfo in case we need it later. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP)
+ save_siginfo (lp);
+
+ /* Handle GNU/Linux's extended waitstatus for trace events. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Handling extended status 0x%06x\n",
+ status);
+ if (linux_handle_extended_wait (lp, status, 0))
+ return NULL;
+ }
+
+ /* Check if the thread has exited. */
+ if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
+ {
+ /* If this is the main thread, we must stop all threads and
+ verify if they are still alive. This is because in the nptl
+ thread model, there is no signal issued for exiting LWPs
+ other than the main thread. We only get the main thread exit
+ signal once all child threads have already exited. If we
+ stop all the threads and use the stop_wait_callback to check
+ if they have exited we can determine whether this signal
+ should be ignored or whether it means the end of the debugged
+ application, regardless of which threading model is being
+ used. */
+ if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
+ {
+ lp->stopped = 1;
+ iterate_over_lwps (stop_and_resume_callback, NULL);
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
+
+ /* If there is at least one more LWP, then the exit signal was
+ not the end of the debugged application and should be
+ ignored. */
+ if (num_lwps > 0)
+ return NULL;
+ }
+
+ /* Check if the current LWP has previously exited. In the nptl
+ thread model, LWPs other than the main thread do not issue
+ signals when they exit so we must check whenever the thread has
+ stopped. A similar check is made in stop_wait_callback(). */
+ if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
+
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (running_callback, NULL));
+
+ /* Discard the event. */
+ return NULL;
+ }
+
+ /* Make sure we don't report a SIGSTOP that we sent ourselves in
+ an attempt to stop an LWP. */
+ if (lp->signalled
+ && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Delayed SIGSTOP caught for %s.\n",
+ target_pid_to_str (lp->ptid));
+
+ /* This is a delayed SIGSTOP. */
+ lp->signalled = 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 SIGSTOP)\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;
+ }
+
+ /* 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;
+}
+
+/* Get the events stored in the pipe into the local queue, so they are
+ accessible to queued_waitpid. We need to do this, since it is not
+ always the case that the event at the head of the pipe is the event
+ we want. */
+
+static void
+pipe_to_local_event_queue (void)
+{
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "PTLEQ: linux_nat_num_queued_events(%d)\n",
+ linux_nat_num_queued_events);
+ while (linux_nat_num_queued_events)
+ {
+ int lwpid, status, options;
+ lwpid = linux_nat_event_pipe_pop (&status, &options);
+ gdb_assert (lwpid > 0);
+ push_waitpid (lwpid, status, options);
+ }
+}
+
+/* Get the unprocessed events stored in the local queue back into the
+ pipe, so the event loop realizes there's something else to
+ process. */
+
+static void
+local_event_queue_to_pipe (void)
+{
+ struct waitpid_result *w = waitpid_queue;
+ while (w)
+ {
+ struct waitpid_result *next = w->next;
+ linux_nat_event_pipe_push (w->pid,
+ w->status,
+ w->options);
+ xfree (w);
+ w = next;
+ }
+ waitpid_queue = NULL;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "LEQTP: linux_nat_num_queued_events(%d)\n",
+ linux_nat_num_queued_events);
+}
+
static ptid_t
-linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
+linux_nat_wait (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus)
{
struct lwp_info *lp = NULL;
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");
/* The first time we get here after starting a new inferior, we may
not have added it to the LWP list yet - this is the earliest
{
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;
}
- sigemptyset (&flush_mask);
-
- /* Make sure SIGCHLD is blocked. */
- if (!sigismember (&blocked_mask, SIGCHLD))
- {
- sigaddset (&blocked_mask, SIGCHLD);
- sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
- }
+ /* Block events while we're here. */
+ linux_nat_async_events (sigchld_sync);
retry:
lp = iterate_over_lwps (status_callback, NULL);
if (lp)
{
+ if (target_can_async_p ())
+ internal_error (__FILE__, __LINE__,
+ "Found an LWP with a pending status in async mode.");
+
status = lp->status;
lp->status = 0;
target_pid_to_str (lp->ptid));
}
- /* But if we don't fine one, we'll have to wait, and check both
+ /* But if we don't find one, we'll have to wait, and check both
cloned and uncloned processes. We start with the cloned
processes. */
options = __WCLONE | WNOHANG;
stop_wait_callback (lp, NULL);
}
- set_sigint_trap (); /* Causes SIGINT to be passed on to the
- attached process. */
- set_sigio_trap ();
+ if (!target_can_async_p ())
+ {
+ /* Causes SIGINT to be passed on to the attached process. */
+ set_sigint_trap ();
+ }
while (status == 0)
{
pid_t lwpid;
- lwpid = my_waitpid (pid, &status, options);
+ if (target_can_async_p ())
+ /* In async mode, don't ever block. Only look at the locally
+ queued events. */
+ lwpid = queued_waitpid (pid, &status, options);
+ else
+ lwpid = my_waitpid (pid, &status, options);
+
if (lwpid > 0)
{
gdb_assert (pid == -1 || lwpid == pid);
(long) lwpid, status_to_str (status));
}
- lp = find_lwp_pid (pid_to_ptid (lwpid));
-
- /* Check for stop events reported by a process we didn't
- already know about - anything not already in our LWP
- list.
-
- If we're expecting to receive stopped processes after
- fork, vfork, and clone events, then we'll just add the
- new one to our list and go back to waiting for the event
- to be reported - the stopped process might be returned
- from waitpid before or after the event is. */
- if (WIFSTOPPED (status) && !lp)
- {
- linux_record_stopped_pid (lwpid, status);
- status = 0;
- continue;
- }
-
- /* Make sure we don't report an event for the exit of an LWP not in
- our list, i.e. not part of the current process. This can happen
- if we detach from a program we original forked and then it
- exits. */
- if (!WIFSTOPPED (status) && !lp)
- {
- status = 0;
- continue;
- }
-
- /* NOTE drow/2003-06-17: This code seems to be meant for debugging
- CLONE_PTRACE processes which do not use the thread library -
- otherwise we wouldn't find the new LWP this way. That doesn't
- currently work, and the following code is currently unreachable
- due to the two blocks above. If it's fixed some day, this code
- should be broken out into a function so that we can also pick up
- LWPs from the new interface. */
+ lp = linux_nat_filter_event (lwpid, status, options);
if (!lp)
{
- lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
- if (options & __WCLONE)
- lp->cloned = 1;
-
- gdb_assert (WIFSTOPPED (status)
- && WSTOPSIG (status) == SIGSTOP);
- lp->signalled = 1;
-
- if (!in_thread_list (inferior_ptid))
- {
- inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
- GET_PID (inferior_ptid));
- add_thread (inferior_ptid);
- }
-
- add_thread (lp->ptid);
- printf_unfiltered (_("[New %s]\n"),
- target_pid_to_str (lp->ptid));
- }
-
- /* Handle GNU/Linux's extended waitstatus for trace events. */
- if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: Handling extended status 0x%06x\n",
- status);
- if (linux_handle_extended_wait (lp, status, 0))
- {
- status = 0;
- continue;
- }
- }
-
- /* Check if the thread has exited. */
- if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
- {
- /* If this is the main thread, we must stop all threads and
- verify if they are still alive. This is because in the nptl
- thread model, there is no signal issued for exiting LWPs
- other than the main thread. We only get the main thread
- exit signal once all child threads have already exited.
- If we stop all the threads and use the stop_wait_callback
- to check if they have exited we can determine whether this
- signal should be ignored or whether it means the end of the
- debugged application, regardless of which threading model
- is being used. */
- if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
- {
- lp->stopped = 1;
- iterate_over_lwps (stop_and_resume_callback, NULL);
- }
-
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s exited.\n",
- target_pid_to_str (lp->ptid));
-
- exit_lwp (lp);
-
- /* If there is at least one more LWP, then the exit signal
- was 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. */
- status = 0;
- continue;
- }
- }
-
- /* Check if the current LWP has previously exited. In the nptl
- thread model, LWPs other than the main thread do not issue
- signals when they exit so we must check whenever the thread
- has stopped. A similar check is made in stop_wait_callback(). */
- if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid))
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s exited.\n",
- target_pid_to_str (lp->ptid));
-
- exit_lwp (lp);
-
- /* Make sure there is at least one thread running. */
- gdb_assert (iterate_over_lwps (running_callback, NULL));
-
- /* Discard the event. */
- status = 0;
- continue;
- }
-
- /* Make sure we don't report a SIGSTOP that we sent
- ourselves in an attempt to stop an LWP. */
- if (lp->signalled
- && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP)
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: Delayed SIGSTOP caught for %s.\n",
- target_pid_to_str (lp->ptid));
-
- /* This is a delayed SIGSTOP. */
- lp->signalled = 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 SIGSTOP)\n",
- lp->step ?
- "PTRACE_SINGLESTEP" : "PTRACE_CONT",
- target_pid_to_str (lp->ptid));
-
- lp->stopped = 0;
- gdb_assert (lp->resumed);
-
- /* Discard the event. */
+ /* A discarded event. */
status = 0;
continue;
}
/* Alternate between checking cloned and uncloned processes. */
options ^= __WCLONE;
- /* And suspend every time we have checked both. */
+ /* And every time we have checked both:
+ In async mode, return to event loop;
+ In sync mode, suspend waiting for a SIGCHLD signal. */
if (options & __WCLONE)
- sigsuspend (&suspend_mask);
+ {
+ if (target_can_async_p ())
+ {
+ /* No interesting event. */
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
+ /* Get ready for the next event. */
+ target_async (inferior_event_handler, 0);
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
+
+ return minus_one_ptid;
+ }
+
+ sigsuspend (&suspend_mask);
+ }
}
/* We shouldn't end up here unless we want to try again. */
gdb_assert (status == 0);
}
- clear_sigio_trap ();
- clear_sigint_trap ();
+ if (!target_can_async_p ())
+ clear_sigint_trap ();
gdb_assert (lp);
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)
{
else
store_waitstatus (ourstatus, status);
+ /* Get ready for the next event. */
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit\n");
+
return lp->ptid;
}
do
{
pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE);
- if (pid != (pid_t) -1 && debug_linux_nat)
+ if (pid != (pid_t) -1)
{
- fprintf_unfiltered (gdb_stdlog,
- "KWC: wait %s received unknown.\n",
- target_pid_to_str (lp->ptid));
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "KWC: wait %s received unknown.\n",
+ target_pid_to_str (lp->ptid));
+ /* The Linux kernel sometimes fails to kill a thread
+ completely after PTRACE_KILL; that goes from the stop
+ point in do_fork out to the one in
+ get_signal_to_deliever and waits again. So kill it
+ again. */
+ kill_callback (lp, NULL);
}
}
while (pid == GET_LWP (lp->ptid));
do
{
pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0);
- if (pid != (pid_t) -1 && debug_linux_nat)
+ if (pid != (pid_t) -1)
{
- fprintf_unfiltered (gdb_stdlog,
- "KWC: wait %s received unk.\n",
- target_pid_to_str (lp->ptid));
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "KWC: wait %s received unk.\n",
+ target_pid_to_str (lp->ptid));
+ /* See the call to kill_callback above. */
+ kill_callback (lp, NULL);
}
}
while (pid == GET_LWP (lp->ptid));
ptid_t last_ptid;
int status;
+ if (target_can_async_p ())
+ target_async (NULL, 0);
+
/* If we're stopped while forking and we haven't followed yet,
kill the other task. We need to do this first because the
parent will be sleeping if this is a vfork. */
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);
}
if (forks_exist_p ())
- linux_fork_killall ();
+ {
+ linux_fork_killall ();
+ drain_queued_events (-1);
+ }
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 ();
- /* Restore the original signal mask. */
- sigprocmask (SIG_SETMASK, &normal_mask, NULL);
- sigemptyset (&blocked_mask);
-
if (! forks_exist_p ())
- /* Normal case, no other forks available. */
- linux_ops->to_mourn_inferior ();
+ {
+ /* Normal case, no other forks available. */
+ if (target_can_async_p ())
+ linux_nat_async (NULL, 0);
+ linux_ops->to_mourn_inferior (ops);
+ }
else
/* Multi-fork case. The current inferior_ptid has exited, but
there are other viable forks to debug. Delete the exiting
}
static LONGEST
-linux_nat_xfer_partial (struct target_ops *ops, enum target_object object,
- const char *annex, gdb_byte *readbuf,
- const gdb_byte *writebuf,
- ULONGEST offset, LONGEST len)
-{
- struct cleanup *old_chain = save_inferior_ptid ();
+linux_xfer_siginfo (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
+{
+ struct lwp_info *lp;
+ LONGEST n;
+ int pid;
+ struct siginfo siginfo;
+
+ gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO);
+ gdb_assert (readbuf || writebuf);
+
+ pid = GET_LWP (inferior_ptid);
+ if (pid == 0)
+ pid = GET_PID (inferior_ptid);
+
+ if (offset > sizeof (siginfo))
+ return -1;
+
+ errno = 0;
+ ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo);
+ if (errno != 0)
+ return -1;
+
+ if (offset + len > sizeof (siginfo))
+ len = sizeof (siginfo) - offset;
+
+ if (readbuf != NULL)
+ memcpy (readbuf, (char *)&siginfo + offset, len);
+ else
+ {
+ memcpy ((char *)&siginfo + offset, writebuf, len);
+ errno = 0;
+ ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo);
+ if (errno != 0)
+ return -1;
+ }
+
+ return len;
+}
+
+static LONGEST
+linux_nat_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, LONGEST len)
+{
+ struct cleanup *old_chain;
LONGEST xfer;
+ if (object == TARGET_OBJECT_SIGNAL_INFO)
+ return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
+ old_chain = save_inferior_ptid ();
+
if (is_lwp (inferior_ptid))
inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid));
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 char *
-linux_nat_pid_to_str (ptid_t ptid)
+linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid)
{
static char buf[64];
- if (lwp_list && lwp_list->next && is_lwp (ptid))
+ if (is_lwp (ptid)
+ && ((lwp_list && lwp_list->next)
+ || GET_PID (ptid) != GET_LWP (ptid)))
{
snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid));
return buf;
static void
sigchld_handler (int signo)
{
+ 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__,
+ "sigchld_handler called when async events are enabled");
+
/* Do nothing. The only reason for this handler is that it allows
us to use sigsuspend in linux_nat_wait above to wait for the
arrival of a SIGCHLD. */
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 gdbarch *gdbarch = current_gdbarch;
+ 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;
+ target_fetch_registers (regcache, -1);
+ 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
&& regset->collect_regset != NULL)
- regset->collect_regset (regset, current_regcache, -1,
+ regset->collect_regset (regset, regcache, -1,
&gregs, sizeof (gregs));
else
- fill_gregset (current_regcache, &gregs, -1);
+ fill_gregset (regcache, &gregs, -1);
note_data = (char *) elfcore_write_prstatus (obfd,
note_data,
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, current_regcache, -1,
- &fpregs, sizeof (fpregs));
- else
- fill_fpregset (current_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, current_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 (current_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
linux_nat_corefile_thread_callback (struct lwp_info *ti, void *data)
{
struct linux_nat_corefile_thread_data *args = data;
- ptid_t saved_ptid = inferior_ptid;
- inferior_ptid = ti->ptid;
- registers_changed ();
- /* FIXME should not be necessary; fill_gregset should do it automatically. */
- target_fetch_registers (current_regcache, -1);
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++;
- inferior_ptid = saved_ptid;
- registers_changed ();
- /* FIXME should not be necessary; fill_gregset should do it automatically. */
- target_fetch_registers (current_regcache, -1);
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)
-{
- registers_changed ();
- /* FIXME should not be necessary; fill_gregset should do it automatically. */
- target_fetch_registers (current_regcache, -1);
- return linux_nat_do_thread_registers (obfd,
- ptid_build (ptid_get_pid (inferior_ptid),
- ptid_get_pid (inferior_ptid),
- 0),
- note_data, note_size);
- return note_data;
-}
-
/* Fills the "to_make_corefile_note" target vector. Builds the note
section for a corefile, and returns it in a malloc buffer. */
{
struct linux_nat_corefile_thread_data thread_args;
struct cleanup *old_chain;
+ /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
char fname[16] = { '\0' };
+ /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
char psargs[80] = { '\0' };
char *note_data = NULL;
ptid_t current_ptid = inferior_ptid;
strncpy (psargs, get_exec_file (0), sizeof (psargs));
if (get_inferior_args ())
{
- strncat (psargs, " ", sizeof (psargs) - strlen (psargs));
- strncat (psargs, get_inferior_args (),
- sizeof (psargs) - strlen (psargs));
+ char *string_end;
+ char *psargs_end = psargs + sizeof (psargs);
+
+ /* linux_elfcore_write_prpsinfo () handles zero unterminated
+ strings fine. */
+ string_end = memchr (psargs, 0, sizeof (psargs));
+ if (string_end != NULL)
+ {
+ *string_end++ = ' ';
+ strncpy (string_end, get_inferior_args (),
+ psargs_end - string_end);
+ }
}
note_data = (char *) elfcore_write_prpsinfo (obfd,
note_data,
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)
{
- fgets (buffer, sizeof (buffer), procfile);
- printf_filtered ("cmdline = '%s'\n", buffer);
- fclose (procfile);
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
+ if (fgets (buffer, sizeof (buffer), procfile))
+ printf_filtered ("cmdline = '%s'\n", buffer);
+ else
+ warning (_("unable to read '%s'"), fname1);
+ 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, "%s ", &buffer[0]) > 0)
+ if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0)
printf_filtered (_("Exec file: %s\n"), buffer);
if (fscanf (procfile, "%c ", &ctmp) > 0)
printf_filtered (_("State: %c\n"), ctmp);
printf_filtered (_("TTY: %d\n"), itmp);
if (fscanf (procfile, "%d ", &itmp) > 0)
printf_filtered (_("TTY owner process group: %d\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Flags: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Minor faults (no memory page): %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Minor faults, children: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Major faults (memory page faults): %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Major faults, children: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("utime: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("stime: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("utime, children: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("stime, children: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("jiffies remaining in current time slice: %d\n"),
- itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("'nice' value: %d\n", itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("jiffies until next timeout: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered ("jiffies until next SIGALRM: %u\n",
- (unsigned int) itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("start time (jiffies since system boot): %d\n"),
- itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Virtual memory size: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Resident set size: %u\n"), (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered ("rlim: %u\n", (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Start of text: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("End of text: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Start of stack: 0x%x\n"), itmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Flags: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Minor faults (no memory page): %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Minor faults, children: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Major faults (memory page faults): %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Major faults, children: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("utime: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("stime: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("utime, children: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("stime, children: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("jiffies remaining in current time slice: %ld\n"),
+ ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("'nice' value: %ld\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("jiffies until next timeout: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("start time (jiffies since system boot): %ld\n"),
+ ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Virtual memory size: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Start of text: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("End of text: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Start of stack: 0x%lx\n"), ltmp);
#if 0 /* Don't know how architecture-dependent the rest is...
Anyway the signal bitmap info is available from "status". */
- if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
- printf_filtered (_("Kernel stack pointer: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
- printf_filtered (_("Kernel instr pointer: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Pending signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Blocked signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Ignored signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Catched signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
- printf_filtered (_("wchan (system call): 0x%x\n"), itmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
+ printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
+ printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp);
+ 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)
offset, len);
}
-/* Create a prototype generic Linux target. The client can override
+/* Create a prototype generic GNU/Linux target. The client can override
it with local methods. */
static void
return t;
}
+/* 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 target-async" command.
+ Someday, linux will always be async. */
+ if (!target_async_permitted)
+ return 0;
+
+ return 1;
+}
+
+/* target_can_async_p implementation. */
+
+static int
+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 target-async" command.
+ Someday, linux will always be async. */
+ 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_mask (int mask)
+{
+ int current_state;
+ current_state = linux_nat_async_mask_value;
+
+ if (current_state != mask)
+ {
+ if (mask == 0)
+ {
+ linux_nat_async (NULL, 0);
+ linux_nat_async_mask_value = mask;
+ }
+ else
+ {
+ linux_nat_async_mask_value = mask;
+ linux_nat_async (inferior_event_handler, 0);
+ }
+ }
+
+ return current_state;
+}
+
+/* Pop an event from the event pipe. */
+
+static int
+linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options)
+{
+ struct waitpid_result event = {0};
+ int ret;
+
+ do
+ {
+ ret = read (linux_nat_event_pipe[0], &event, sizeof (event));
+ }
+ while (ret == -1 && errno == EINTR);
+
+ gdb_assert (ret == sizeof (event));
+
+ *ptr_status = event.status;
+ *ptr_options = event.options;
+
+ linux_nat_num_queued_events--;
+
+ return event.pid;
+}
+
+/* Push an event into the event pipe. */
+
+static void
+linux_nat_event_pipe_push (int pid, int status, int options)
+{
+ int ret;
+ struct waitpid_result event = {0};
+ event.pid = pid;
+ event.status = status;
+ event.options = options;
+
+ do
+ {
+ ret = write (linux_nat_event_pipe[1], &event, sizeof (event));
+ gdb_assert ((ret == -1 && errno == EINTR) || ret == sizeof (event));
+ } while (ret == -1 && errno == EINTR);
+
+ linux_nat_num_queued_events++;
+}
+
+static void
+get_pending_events (void)
+{
+ int status, options, pid;
+
+ if (!target_async_permitted
+ || linux_nat_async_events_state != sigchld_async)
+ internal_error (__FILE__, __LINE__,
+ "get_pending_events called with async masked");
+
+ while (1)
+ {
+ status = 0;
+ options = __WCLONE | WNOHANG;
+
+ do
+ {
+ pid = waitpid (-1, &status, options);
+ }
+ while (pid == -1 && errno == EINTR);
+
+ if (pid <= 0)
+ {
+ options = WNOHANG;
+ do
+ {
+ pid = waitpid (-1, &status, options);
+ }
+ while (pid == -1 && errno == EINTR);
+ }
+
+ if (pid <= 0)
+ /* No more children reporting events. */
+ break;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "\
+get_pending_events: pid(%d), status(%x), options (%x)\n",
+ pid, status, options);
+
+ linux_nat_event_pipe_push (pid, status, options);
+ }
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "\
+get_pending_events: linux_nat_num_queued_events(%d)\n",
+ linux_nat_num_queued_events);
+}
+
+/* SIGCHLD handler for async mode. */
+
+static void
+async_sigchld_handler (int signo)
+{
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "async_sigchld_handler\n");
+
+ get_pending_events ();
+}
+
+/* Set SIGCHLD handling state to STATE. Returns previous state. */
+
+static enum sigchld_state
+linux_nat_async_events (enum sigchld_state state)
+{
+ enum sigchld_state current_state = linux_nat_async_events_state;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNAE: state(%d): linux_nat_async_events_state(%d), "
+ "linux_nat_num_queued_events(%d)\n",
+ state, linux_nat_async_events_state,
+ linux_nat_num_queued_events);
+
+ if (current_state != state)
+ {
+ sigset_t mask;
+ sigemptyset (&mask);
+ sigaddset (&mask, SIGCHLD);
+
+ /* Always block before changing state. */
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+
+ /* Set new state. */
+ linux_nat_async_events_state = state;
+
+ switch (state)
+ {
+ 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;
+ }
+ }
+
+ return current_state;
+}
+
+static int async_terminal_is_ours = 1;
+
+/* target_terminal_inferior implementation. */
+
+static void
+linux_nat_terminal_inferior (void)
+{
+ if (!target_is_async_p ())
+ {
+ /* Async mode is disabled. */
+ terminal_inferior ();
+ return;
+ }
+
+ /* GDB should never give the terminal to the inferior, if the
+ inferior is running in the background (run&, continue&, etc.).
+ This check can be removed when the common code is fixed. */
+ if (!sync_execution)
+ return;
+
+ terminal_inferior ();
+
+ if (!async_terminal_is_ours)
+ return;
+
+ delete_file_handler (input_fd);
+ async_terminal_is_ours = 0;
+ set_sigint_trap ();
+}
+
+/* target_terminal_ours implementation. */
+
+void
+linux_nat_terminal_ours (void)
+{
+ if (!target_is_async_p ())
+ {
+ /* Async mode is disabled. */
+ terminal_ours ();
+ return;
+ }
+
+ /* GDB should never give the terminal to the inferior if the
+ inferior is running in the background (run&, continue&, etc.),
+ but claiming it sure should. */
+ terminal_ours ();
+
+ if (!sync_execution)
+ return;
+
+ if (async_terminal_is_ours)
+ return;
+
+ clear_sigint_trap ();
+ add_file_handler (input_fd, stdin_event_handler, 0);
+ async_terminal_is_ours = 1;
+}
+
+static void (*async_client_callback) (enum inferior_event_type event_type,
+ void *context);
+static void *async_client_context;
+
+static void
+linux_nat_async_file_handler (int error, gdb_client_data client_data)
+{
+ async_client_callback (INF_REG_EVENT, async_client_context);
+}
+
+/* target_async implementation. */
+
+static void
+linux_nat_async (void (*callback) (enum inferior_event_type event_type,
+ void *context), void *context)
+{
+ if (linux_nat_async_mask_value == 0 || !target_async_permitted)
+ internal_error (__FILE__, __LINE__,
+ "Calling target_async when async is masked");
+
+ if (callback != NULL)
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+ add_file_handler (linux_nat_event_pipe[0],
+ linux_nat_async_file_handler, NULL);
+
+ linux_nat_async_events (sigchld_async);
+ }
+ else
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+
+ linux_nat_async_events (sigchld_sync);
+ delete_file_handler (linux_nat_event_pipe[0]);
+ }
+ return;
+}
+
+/* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
+ event came out. */
+
+static int
+linux_nat_stop_lwp (struct lwp_info *lwp, void *data)
+{
+ 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 (!lwp->stopped)
+ {
+ int pid, status;
+
+ 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);
+
+ /* 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
+ {
+ /* 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));
+ }
+ }
+ }
+ 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
linux_nat_add_target (struct target_ops *t)
{
linux_ops = &linux_ops_saved;
/* Override some methods for multithreading. */
+ t->to_create_inferior = linux_nat_create_inferior;
t->to_attach = linux_nat_attach;
t->to_detach = linux_nat_detach;
t->to_resume = linux_nat_resume;
t->to_pid_to_str = linux_nat_pid_to_str;
t->to_has_thread_control = tc_schedlock;
+ 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
also want to be used for single-threaded processes. */
add_target (t);
+}
+
+/* Register a method to call whenever a new thread is attached. */
+void
+linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t))
+{
+ /* Save the pointer. We only support a single registered instance
+ of the GNU/Linux native target, so we do not need to map this to
+ T. */
+ linux_nat_new_thread = new_thread;
+}
+
+/* Return the saved siginfo associated with PTID. */
+struct siginfo *
+linux_nat_get_siginfo (ptid_t ptid)
+{
+ struct lwp_info *lp = find_lwp_pid (ptid);
+
+ gdb_assert (lp != NULL);
- /* TODO: Eliminate this and have libthread_db use
- find_target_beneath. */
- thread_db_init (t);
+ 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)
{
- struct sigaction action;
+ sigset_t mask;
add_info ("proc", linux_nat_info_proc_cmd, _("\
Show /proc process information about any running process.\n\
status -- list a different bunch of random process info.\n\
all -- list all available /proc info."));
- /* Save the original signal mask. */
+ add_setshow_zinteger_cmd ("lin-lwp", class_maintenance,
+ &debug_linux_nat, _("\
+Set debugging of GNU/Linux lwp module."), _("\
+Show debugging of GNU/Linux lwp module."), _("\
+Enables printf debugging output."),
+ NULL,
+ show_debug_linux_nat,
+ &setdebuglist, &showdebuglist);
+
+ add_setshow_zinteger_cmd ("lin-lwp-async", class_maintenance,
+ &debug_linux_nat_async, _("\
+Set debugging of GNU/Linux async lwp module."), _("\
+Show debugging of GNU/Linux async lwp module."), _("\
+Enables printf debugging output."),
+ NULL,
+ show_debug_linux_nat_async,
+ &setdebuglist, &showdebuglist);
+
+ /* 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
+ inferior is starting (sigsetjmp/siglongjmp). */
+ sigemptyset (&mask);
+ sigaddset (&mask, SIGCHLD);
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+
+ /* Save this mask as the default. */
sigprocmask (SIG_SETMASK, NULL, &normal_mask);
- action.sa_handler = sigchld_handler;
- sigemptyset (&action.sa_mask);
- action.sa_flags = SA_RESTART;
- sigaction (SIGCHLD, &action, NULL);
+ /* The synchronous SIGCHLD handler. */
+ sync_sigchld_action.sa_handler = sigchld_handler;
+ sigemptyset (&sync_sigchld_action.sa_mask);
+ sync_sigchld_action.sa_flags = SA_RESTART;
+
+ /* Make it the default. */
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
/* Make sure we don't block SIGCHLD during a sigsuspend. */
sigprocmask (SIG_SETMASK, NULL, &suspend_mask);
sigdelset (&suspend_mask, SIGCHLD);
- sigemptyset (&blocked_mask);
-
- add_setshow_zinteger_cmd ("lin-lwp", no_class, &debug_linux_nat, _("\
-Set debugging of GNU/Linux lwp module."), _("\
-Show debugging of GNU/Linux lwp module."), _("\
-Enables printf debugging output."),
- NULL,
- show_debug_linux_nat,
- &setdebuglist, &showdebuglist);
+ /* SIGCHLD handler for async mode. */
+ async_sigchld_action.sa_handler = async_sigchld_handler;
+ sigemptyset (&async_sigchld_action.sa_mask);
+ async_sigchld_action.sa_flags = SA_RESTART;
+
+ 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
{
struct sigaction action;
int restart, cancel;
+ sigset_t blocked_mask;
+ sigemptyset (&blocked_mask);
sigemptyset (set);
restart = get_signo ("__pthread_sig_restart");
/* ... except during a sigsuspend. */
sigdelset (&suspend_mask, cancel);
}
-
projects / binutils-gdb.git / blobdiff