X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=gdb%2Flinux-nat.c;h=9511815ecd6f478ce87714dda4465d54abe3b06b;hb=ea42b34a37453fb7cf3a4ac7a5a6d0d456623fd9;hp=e8cc7c55b575ccf65d6fd78f04647442467ded21;hpb=594f77850bb22a2cec4e8fc44c7ea735a6270eb2;p=deliverable%2Fbinutils-gdb.git
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index e8cc7c55b5..9511815ecd 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -1,13 +1,13 @@
/* 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
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,
@@ -16,9 +16,7 @@
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 . */
#include "defs.h"
#include "inferior.h"
@@ -48,6 +46,9 @@
#include "gdbthread.h" /* for struct thread_info etc. */
#include "gdb_stat.h" /* for struct stat */
#include /* for O_RDONLY */
+#include "inf-loop.h"
+#include "event-loop.h"
+#include "event-top.h"
#ifndef O_LARGEFILE
#define O_LARGEFILE 0
@@ -86,11 +87,18 @@
#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 *,
@@ -108,6 +116,15 @@ show_debug_linux_nat (struct ui_file *file, int from_tty,
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 linux_parent_pid;
struct simple_pid_list
@@ -128,6 +145,158 @@ static int linux_supports_tracefork_flag = -1;
static int linux_supports_tracevforkdone_flag = -1;
+/* Async mode support */
+
+/* To listen to target events asynchronously, we install a SIGCHLD
+ handler whose duty is to call waitpid (-1, ..., WNOHANG) to get all
+ the pending events into a pipe. Whenever we're ready to handle
+ events asynchronously, this pipe is registered as the waitable file
+ handle in the event loop. When we get to entry target points
+ coming out of the common code (target_wait, target_resume, ...),
+ that are going to call waitpid, we block SIGCHLD signals, and
+ remove all the events placed in the pipe into a local queue. All
+ the subsequent calls to my_waitpid (a waitpid wrapper) check this
+ local queue first. */
+
+/* True if async mode is currently on. */
+static int linux_nat_async_enabled;
+
+/* Zero if the async mode, although enabled, is masked, which means
+ linux_nat_wait should behave as if async mode was off. */
+static int linux_nat_async_mask_value = 1;
+
+/* 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;
+
+/* If async mode is on, true if we're listening for events; false if
+ target events are blocked. */
+static int linux_nat_async_events_enabled;
+
+static int linux_nat_async_events (int 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);
+
+/* 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;
+
+static int
+queued_waitpid (int pid, int *status, int flags)
+{
+ struct waitpid_result *msg = waitpid_queue, *prev = NULL;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "\
+QWPID: linux_nat_async_events_enabled(%d), linux_nat_num_queued_events(%d)\n",
+ linux_nat_async_events_enabled,
+ 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 (prev)
+ prev->next = msg->next;
+ else
+ waitpid_queue = msg->next;
+
+ msg->next = NULL;
+ if (status)
+ *status = msg->status;
+ pid = msg->pid;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "QWPID: pid(%d), status(%x)\n",
+ pid, msg->status);
+ xfree (msg);
+
+ return pid;
+ }
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "QWPID: miss\n");
+
+ if (status)
+ *status = 0;
+ return -1;
+}
+
+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)
+ ;
+}
+
/* Trivial list manipulation functions to keep track of a list of
new stopped processes. */
@@ -178,12 +347,21 @@ linux_tracefork_child (void)
_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_enabled);
+
+ ret = queued_waitpid (pid, status, flags);
+ if (ret != -1)
+ return ret;
+
do
{
ret = waitpid (pid, status, flags);
@@ -357,6 +535,9 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child)
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);
@@ -378,7 +559,7 @@ linux_child_follow_fork (struct target_ops *ops, int 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,
@@ -463,7 +644,7 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child)
/* 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,
@@ -501,21 +682,24 @@ linux_child_follow_fork (struct target_ops *ops, int follow_child)
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). */
push_target (ops);
+ linux_nat_switch_fork (inferior_ptid);
+ check_for_thread_db ();
/* Reset breakpoints in the child as appropriate. */
follow_inferior_reset_breakpoints ();
}
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+
return 0;
}
@@ -575,17 +759,12 @@ linux_child_insert_exec_catchpoint (int pid)
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;
-#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;
@@ -609,14 +788,19 @@ 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;
/* 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);
+
/* Convert wait status STATUS to a string. Used for printing debug
messages only. */
@@ -659,7 +843,8 @@ init_lwp_list (void)
}
/* 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)
@@ -680,6 +865,9 @@ 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;
}
@@ -802,20 +990,6 @@ prune_lwps (void)
p = &(*p)->next;
}
-/* Callback for iterate_over_threads that finds a thread corresponding
- to the given LWP. */
-
-static int
-find_thread_from_lwp (struct thread_info *thr, void *dummy)
-{
- ptid_t *ptid_p = dummy;
-
- if (GET_LWP (thr->ptid) && GET_LWP (thr->ptid) == GET_LWP (*ptid_p))
- return 1;
- else
- return 0;
-}
-
/* Handle the exit of a single thread LP. */
static void
@@ -823,32 +997,14 @@ exit_lwp (struct lwp_info *lp)
{
if (in_thread_list (lp->ptid))
{
+ if (print_thread_events)
+ printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid));
+
/* Core GDB cannot deal with us deleting the current thread. */
if (!ptid_equal (lp->ptid, inferior_ptid))
delete_thread (lp->ptid);
else
record_dead_thread (lp->ptid);
- printf_unfiltered (_("[%s exited]\n"),
- target_pid_to_str (lp->ptid));
- }
- else
- {
- /* 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. */
-
- struct thread_info *thr;
-
- 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);
- }
}
delete_lwp (lp->ptid);
@@ -860,19 +1016,15 @@ exit_lwp (struct lwp_info *lp)
be attached. */
int
-lin_lwp_attach_lwp (ptid_t ptid, int verbose)
+lin_lwp_attach_lwp (ptid_t ptid)
{
struct lwp_info *lp;
+ int async_events_were_enabled = 0;
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);
- }
+ if (target_can_async_p ())
+ async_events_were_enabled = linux_nat_async_events (0);
lp = find_lwp_pid (ptid);
@@ -886,12 +1038,13 @@ lin_lwp_attach_lwp (ptid_t ptid, int verbose)
{
pid_t pid;
int status;
+ int cloned = 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),
@@ -899,9 +1052,6 @@ lin_lwp_attach_lwp (ptid_t ptid, int verbose)
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",
@@ -912,12 +1062,16 @@ lin_lwp_attach_lwp (ptid_t ptid, int verbose)
{
/* Try again with __WCLONE to check cloned processes. */
pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE);
- lp->cloned = 1;
+ cloned = 1;
}
gdb_assert (pid == GET_LWP (ptid)
&& WIFSTOPPED (status) && WSTOPSIG (status));
+ if (lp == NULL)
+ lp = add_lwp (ptid);
+ lp->cloned = cloned;
+
target_post_attach (pid);
lp->stopped = 1;
@@ -943,52 +1097,105 @@ lin_lwp_attach_lwp (ptid_t ptid, int verbose)
lp->stopped = 1;
}
- if (verbose)
- printf_filtered (_("[New %s]\n"), target_pid_to_str (ptid));
+ if (async_events_were_enabled)
+ linux_nat_async_events (1);
return 0;
}
+static void
+linux_nat_create_inferior (char *exec_file, char *allargs, char **env,
+ int from_tty)
+{
+ int saved_async = 0;
+
+ /* The fork_child mechanism is synchronous and calls target_wait, so
+ we have to mask the async mode. */
+
+ if (target_can_async_p ())
+ 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);
+ }
+
+ linux_ops->to_create_inferior (exec_file, allargs, env, from_tty);
+
+ if (saved_async)
+ linux_nat_async_mask (saved_async);
+}
+
static void
linux_nat_attach (char *args, int from_tty)
{
struct lwp_info *lp;
pid_t pid;
int status;
+ int cloned = 0;
+ int options = 0;
/* 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);
+ if (!target_can_async_p ())
+ {
+ /* 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);
+ }
/* 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);
+ pid = my_waitpid (GET_PID (inferior_ptid), &status, options);
if (pid == -1 && errno == ECHILD)
{
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;
+ options = __WCLONE;
+ pid = my_waitpid (GET_PID (inferior_ptid), &status, options);
+ cloned = 1;
}
gdb_assert (pid == GET_PID (inferior_ptid)
&& WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP);
- lp->stopped = 1;
+ /* Add the initial process as the first LWP to the list. */
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
+ lp = add_lwp (inferior_ptid);
+ lp->cloned = cloned;
- /* Fake the SIGSTOP that core GDB expects. */
- lp->status = W_STOPCODE (SIGSTOP);
+ /* If this process is not using thread_db, then we still don't
+ detect any other threads, but add at least this one. */
+ add_thread_silent (lp->ptid);
+
+ lp->stopped = 1;
lp->resumed = 1;
- if (debug_linux_nat)
+
+ if (!target_can_async_p ())
{
- fprintf_unfiltered (gdb_stdlog,
- "LLA: waitpid %ld, faking SIGSTOP\n", (long) pid);
+ /* Fake the SIGSTOP that core GDB expects. */
+ lp->status = W_STOPCODE (SIGSTOP);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNA: waitpid %ld, faking SIGSTOP\n", (long) pid);
+ }
+ else
+ {
+ /* 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 (pid, status, options);
+ /* Register in the event loop. */
+ target_async (inferior_event_handler, 0);
}
}
@@ -1045,6 +1252,7 @@ detach_callback (struct lwp_info *lp, void *data)
target_pid_to_str (lp->ptid),
strsignal (WSTOPSIG (lp->status)));
+ drain_queued_events (GET_LWP (lp->ptid));
delete_lwp (lp->ptid);
}
@@ -1054,6 +1262,10 @@ detach_callback (struct lwp_info *lp, void *data)
static void
linux_nat_detach (char *args, int from_tty)
{
+ int pid;
+ if (target_can_async_p ())
+ linux_nat_async (NULL, 0);
+
iterate_over_lwps (detach_callback, NULL);
/* Only the initial process should be left right now. */
@@ -1064,12 +1276,12 @@ linux_nat_detach (char *args, int from_tty)
/* 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);
-
- inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid));
+ pid = GET_PID (inferior_ptid);
+ inferior_ptid = pid_to_ptid (pid);
linux_ops->to_detach (args, from_tty);
+
+ if (target_can_async_p ())
+ drain_queued_events (pid);
}
/* Resume LP. */
@@ -1079,8 +1291,6 @@ resume_callback (struct lwp_info *lp, void *data)
{
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)
@@ -1089,6 +1299,7 @@ resume_callback (struct lwp_info *lp, void *data)
target_pid_to_str (lp->ptid));
lp->stopped = 0;
lp->step = 0;
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
}
return 0;
@@ -1124,6 +1335,10 @@ linux_nat_resume (ptid_t ptid, int step, enum target_signal signo)
prune_lwps ();
+ if (target_can_async_p ())
+ /* Block events while we're here. */
+ linux_nat_async_events (0);
+
/* A specific PTID means `step only this process id'. */
resume_all = (PIDGET (ptid) == -1);
@@ -1138,74 +1353,85 @@ linux_nat_resume (ptid_t ptid, int step, enum target_signal signo)
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;
+ 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 && WIFSTOPPED (lp->status))
+ {
+ int saved_signo = target_signal_from_host (WSTOPSIG (lp->status));
- if (lp->status)
+ 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;
+ }
+ }
- 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_executing = 1;
+ target_async (inferior_event_handler, 0);
+ }
}
/* Issue kill to specified lwp. */
@@ -1418,6 +1644,22 @@ wait_lwp (struct lwp_info *lp)
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
@@ -1503,6 +1745,9 @@ stop_wait_callback (struct lwp_info *lp, void *data)
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);
@@ -1517,22 +1762,44 @@ stop_wait_callback (struct lwp_info *lp, void *data)
"SWC: Candidate SIGTRAP event in %s\n",
target_pid_to_str (lp->ptid));
}
- /* Hold the SIGTRAP for handling by linux_nat_wait. */
+ /* 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 there's another event, throw it back into the queue. */
- if (lp->status)
+
+ 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: kill %s, %s\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str ((int) status));
+ kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
+ }
+ }
+ 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
@@ -1559,12 +1826,11 @@ stop_wait_callback (struct lwp_info *lp, void *data)
/* 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
+
+ /* 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)
{
@@ -1575,6 +1841,8 @@ stop_wait_callback (struct lwp_info *lp, void *data)
}
kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
}
+ else
+ lp->status = status;
return 0;
}
}
@@ -1744,6 +2012,37 @@ select_event_lwp_callback (struct lwp_info *lp, void *data)
return 0;
}
+static int
+cancel_breakpoint (struct lwp_info *lp)
+{
+ /* 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
+ 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 (breakpoint_inserted_here_p (read_pc_pid (lp->ptid) -
+ gdbarch_decr_pc_after_break
+ (current_gdbarch)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "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);
+ return 1;
+ }
+ return 0;
+}
+
static int
cancel_breakpoints_callback (struct lwp_info *lp, void *data)
{
@@ -1766,24 +2065,9 @@ cancel_breakpoints_callback (struct lwp_info *lp, void *data)
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)))
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "CBC: 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);
-
- /* Throw away the SIGTRAP. */
- lp->status = 0;
- }
+ && cancel_breakpoint (lp))
+ /* Throw away the SIGTRAP. */
+ lp->status = 0;
return 0;
}
@@ -1871,49 +2155,268 @@ stop_and_resume_callback (struct lwp_info *lp, void *data)
return 0;
}
-static ptid_t
-linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
+/* 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 = NULL;
- int options = 0;
- int status = 0;
- pid_t pid = PIDGET (ptid);
- sigset_t flush_mask;
-
- /* 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
- moment at which we know its PID. */
- if (num_lwps == 0)
- {
- gdb_assert (!is_lwp (inferior_ptid));
+ struct lwp_info *lp;
- inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
- GET_PID (inferior_ptid));
- lp = add_lwp (inferior_ptid);
- lp->resumed = 1;
- }
+ lp = find_lwp_pid (pid_to_ptid (lwpid));
- sigemptyset (&flush_mask);
+ /* Check for stop events reported by a process we didn't already
+ know about - anything not already in our LWP list.
- /* Make sure SIGCHLD is blocked. */
- if (!sigismember (&blocked_mask, SIGCHLD))
+ 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)
{
- sigaddset (&blocked_mask, SIGCHLD);
- sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
+ linux_record_stopped_pid (lwpid, status);
+ return NULL;
}
-retry:
+ /* 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;
- /* Make sure there is at least one LWP that has been resumed. */
- gdb_assert (iterate_over_lwps (resumed_callback, NULL));
+ gdb_assert (WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGSTOP);
+ lp->signalled = 1;
- /* First check if there is a LWP with a wait status pending. */
- if (pid == -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)
+ {
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (running_callback, NULL));
+
+ /* Discard the event. */
+ 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;
+ }
+
+ /* 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)
+{
+ 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
+ moment at which we know its PID. */
+ if (num_lwps == 0)
+ {
+ gdb_assert (!is_lwp (inferior_ptid));
+
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ lp = add_lwp (inferior_ptid);
+ lp->resumed = 1;
+ /* Add the main thread to GDB's thread list. */
+ add_thread_silent (lp->ptid);
+ }
+
+ sigemptyset (&flush_mask);
+
+ if (target_can_async_p ())
+ /* Block events while we're here. */
+ target_async (NULL, 0);
+
+retry:
+
+ /* Make sure there is at least one LWP that has been resumed. */
+ gdb_assert (iterate_over_lwps (resumed_callback, NULL));
+
+ /* First check if there is a LWP with a wait status pending. */
+ if (pid == -1)
+ {
/* Any LWP that's been resumed will do. */
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;
@@ -1924,7 +2427,7 @@ retry:
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;
@@ -1983,15 +2486,24 @@ retry:
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 ();
+ set_sigio_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);
@@ -2003,165 +2515,10 @@ retry:
(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;
}
@@ -2174,17 +2531,38 @@ retry:
/* 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_sigio_trap ();
+ clear_sigint_trap ();
+ }
gdb_assert (lp);
@@ -2281,6 +2659,13 @@ retry:
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;
}
@@ -2315,11 +2700,18 @@ kill_wait_callback (struct lwp_info *lp, void *data)
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));
@@ -2330,11 +2722,14 @@ kill_wait_callback (struct lwp_info *lp, void *data)
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));
@@ -2350,6 +2745,9 @@ linux_nat_kill (void)
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. */
@@ -2364,7 +2762,10 @@ linux_nat_kill (void)
}
if (forks_exist_p ())
- linux_fork_killall ();
+ {
+ linux_fork_killall ();
+ drain_queued_events (-1);
+ }
else
{
/* Kill all LWP's ... */
@@ -2385,13 +2786,13 @@ linux_nat_mourn_inferior (void)
/* 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 ();
+ }
else
/* Multi-fork case. The current inferior_ptid has exited, but
there are other viable forks to debug. Delete the exiting
@@ -2459,6 +2860,13 @@ linux_nat_pid_to_str (ptid_t ptid)
static void
sigchld_handler (int signo)
{
+ if (linux_nat_async_enabled
+ && linux_nat_async_events_enabled
+ && 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. */
@@ -2688,7 +3096,9 @@ linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
{
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;
@@ -2701,9 +3111,18 @@ linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
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,
@@ -2926,10 +3345,11 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
{
int itmp;
char ctmp;
+ long ltmp;
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);
@@ -2943,71 +3363,71 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
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);
}
@@ -3163,7 +3583,7 @@ linux_xfer_partial (struct target_ops *ops, enum target_object object,
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
@@ -3205,6 +3625,376 @@ linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int))
return t;
}
+/* Controls if async mode is permitted. */
+static int linux_async_permitted = 0;
+
+/* The set command writes to this variable. If the inferior is
+ executing, linux_nat_async_permitted is *not* updated. */
+static int linux_async_permitted_1 = 0;
+
+static void
+set_maintenance_linux_async_permitted (char *args, int from_tty,
+ struct cmd_list_element *c)
+{
+ if (target_has_execution)
+ {
+ linux_async_permitted_1 = linux_async_permitted;
+ error (_("Cannot change this setting while the inferior is running."));
+ }
+
+ linux_async_permitted = linux_async_permitted_1;
+ linux_nat_set_async_mode (linux_async_permitted);
+}
+
+static void
+show_maintenance_linux_async_permitted (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("\
+Controlling the GNU/Linux inferior in asynchronous mode is %s.\n"),
+ value);
+}
+
+/* target_is_async_p implementation. */
+
+static int
+linux_nat_is_async_p (void)
+{
+ /* NOTE: palves 2008-03-21: We're only async when the user requests
+ it explicitly with the "maintenance set linux-async" command.
+ Someday, linux will always be async. */
+ if (!linux_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 linux-async" command.
+ Someday, linux will always be async. */
+ if (!linux_async_permitted)
+ return 0;
+
+ /* See target.h/target_async_mask. */
+ return linux_nat_async_mask_value;
+}
+
+/* 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;
+ /* We're in sync mode. Make sure SIGCHLD isn't handled by
+ async_sigchld_handler when we come out of sigsuspend in
+ linux_nat_wait. */
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
+ }
+ else
+ {
+ /* Restore the async handler. */
+ sigaction (SIGCHLD, &async_sigchld_action, NULL);
+ linux_nat_async_mask_value = mask;
+ linux_nat_async (inferior_event_handler, 0);
+ }
+ }
+
+ 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 (!linux_nat_async_enabled || !linux_nat_async_events_enabled)
+ 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 ();
+}
+
+/* Enable or disable async SIGCHLD handling. */
+
+static int
+linux_nat_async_events (int enable)
+{
+ int current_state = linux_nat_async_events_enabled;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNAE: enable(%d): linux_nat_async_events_enabled(%d), "
+ "linux_nat_num_queued_events(%d)\n",
+ enable, linux_nat_async_events_enabled,
+ linux_nat_num_queued_events);
+
+ if (current_state != enable)
+ {
+ sigset_t mask;
+ sigemptyset (&mask);
+ sigaddset (&mask, SIGCHLD);
+ if (enable)
+ {
+ /* Unblock target events. */
+ linux_nat_async_events_enabled = 1;
+
+ local_event_queue_to_pipe ();
+ /* While in masked async, we may have not collected all the
+ pending events. Get them out now. */
+ get_pending_events ();
+ sigprocmask (SIG_UNBLOCK, &mask, NULL);
+ }
+ else
+ {
+ /* Block target events. */
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+ linux_nat_async_events_enabled = 0;
+ /* Get events out of queue, and make them available to
+ queued_waitpid / my_waitpid. */
+ pipe_to_local_event_queue ();
+ }
+ }
+
+ 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 || !linux_nat_async_enabled)
+ 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 (1);
+ }
+ else
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+
+ linux_nat_async_events (0);
+ delete_file_handler (linux_nat_event_pipe[0]);
+ }
+ return;
+}
+
+/* Enable/Disable async mode. */
+
+static void
+linux_nat_set_async_mode (int on)
+{
+ if (linux_nat_async_enabled != on)
+ {
+ if (on)
+ {
+ gdb_assert (waitpid_queue == NULL);
+ sigaction (SIGCHLD, &async_sigchld_action, NULL);
+
+ 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);
+ }
+ else
+ {
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
+
+ drain_queued_events (-1);
+
+ linux_nat_num_queued_events = 0;
+ close (linux_nat_event_pipe[0]);
+ close (linux_nat_event_pipe[1]);
+ linux_nat_event_pipe[0] = linux_nat_event_pipe[1] = -1;
+
+ }
+ }
+ linux_nat_async_enabled = on;
+}
+
void
linux_nat_add_target (struct target_ops *t)
{
@@ -3216,6 +4006,7 @@ 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;
@@ -3227,6 +4018,13 @@ linux_nat_add_target (struct target_ops *t)
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_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;
+
/* 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
@@ -3240,10 +4038,31 @@ linux_nat_add_target (struct target_ops *t)
thread_db_init (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);
+
+ return &lp->siginfo;
+}
+
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\
@@ -3254,27 +4073,63 @@ Specify any of the following keywords for detailed info:\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);
+
+ add_setshow_boolean_cmd ("linux-async", class_maintenance,
+ &linux_async_permitted_1, _("\
+Set whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\
+Show whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\
+Tells gdb whether to control the GNU/Linux inferior in asynchronous mode."),
+ set_maintenance_linux_async_permitted,
+ show_maintenance_linux_async_permitted,
+ &maintenance_set_cmdlist,
+ &maintenance_show_cmdlist);
+
+ /* 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);
+ /* 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;
- 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);
+ /* Install the default mode. */
+ linux_nat_set_async_mode (linux_async_permitted);
}
@@ -3310,7 +4165,9 @@ lin_thread_get_thread_signals (sigset_t *set)
{
struct sigaction action;
int restart, cancel;
+ sigset_t blocked_mask;
+ sigemptyset (&blocked_mask);
sigemptyset (set);
restart = get_signo ("__pthread_sig_restart");