X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Flinux-nat.c;h=0679173764cf3f6593b3b930ef081d8f3f862f6e;hb=5d3b6af6f9b3416184e5b87e5fd3fc4483cf6f81;hp=f050e7e83f91545f2f90f89e5ff562de0140f542;hpb=01f0fe5e0450edf168c1f612feb93cf588e4e7ea;p=deliverable%2Fbinutils-gdb.git
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index f050e7e83f..0679173764 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
+ 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,
@@ -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"
@@ -36,6 +34,7 @@
#include "gdbthread.h"
#include "gdbcmd.h"
#include "regcache.h"
+#include "regset.h"
#include "inf-ptrace.h"
#include "auxv.h"
#include /* for MAXPATHLEN */
@@ -47,6 +46,115 @@
#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"
+#include
+#include
+#include "gdb_dirent.h"
+#include "xml-support.h"
+
+#ifdef HAVE_PERSONALITY
+# include
+# 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
@@ -85,11 +193,26 @@
#define __WALL 0x40000000 /* Wait for any child. */
#endif
+#ifndef PTRACE_GETSIGINFO
+# define PTRACE_GETSIGINFO 0x4202
+# define PTRACE_SETSIGINFO 0x4203
+#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 method to call, if any, when the siginfo object needs to be
+ converted between the layout returned by ptrace, and the layout in
+ the architecture of the inferior. */
+static int (*linux_nat_siginfo_fixup) (struct siginfo *,
+ gdb_byte *,
+ int);
+
/* 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 *,
@@ -107,11 +230,48 @@ 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 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
{
int pid;
+ int status;
struct simple_pid_list *next;
};
struct simple_pid_list *stopped_pids;
@@ -126,20 +286,191 @@ static int linux_supports_tracefork_flag = -1;
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)
+ ;
+}
+
/* Trivial list manipulation functions to keep track of a list of
new stopped processes. */
static void
-add_to_pid_list (struct simple_pid_list **listp, int pid)
+add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
{
struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list));
new_pid->pid = pid;
+ new_pid->status = status;
new_pid->next = *listp;
*listp = new_pid;
}
static int
-pull_pid_from_list (struct simple_pid_list **listp, int pid)
+pull_pid_from_list (struct simple_pid_list **listp, int pid, int *status)
{
struct simple_pid_list **p;
@@ -147,6 +478,7 @@ pull_pid_from_list (struct simple_pid_list **listp, int pid)
if ((*p)->pid == pid)
{
struct simple_pid_list *next = (*p)->next;
+ *status = (*p)->status;
xfree (*p);
*p = next;
return 1;
@@ -154,10 +486,10 @@ pull_pid_from_list (struct simple_pid_list **listp, int pid)
return 0;
}
-void
-linux_record_stopped_pid (int pid)
+static void
+linux_record_stopped_pid (int pid, int status)
{
- add_to_pid_list (&stopped_pids, pid);
+ add_to_pid_list (&stopped_pids, pid, status);
}
@@ -174,12 +506,21 @@ 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_state == sigchld_sync);
+
+ ret = queued_waitpid (pid, status, flags);
+ if (ret != -1)
+ return ret;
+
do
{
ret = waitpid (pid, status, flags);
@@ -207,6 +548,9 @@ linux_test_for_tracefork (int original_pid)
{
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;
@@ -237,6 +581,7 @@ linux_test_for_tracefork (int original_pid)
if (ret != 0)
{
warning (_("linux_test_for_tracefork: failed to kill child"));
+ linux_nat_async_events (async_events_original_state);
return;
}
@@ -247,6 +592,7 @@ linux_test_for_tracefork (int original_pid)
warning (_("linux_test_for_tracefork: unexpected wait status 0x%x from "
"killed child"), status);
+ linux_nat_async_events (async_events_original_state);
return;
}
@@ -275,6 +621,7 @@ linux_test_for_tracefork (int original_pid)
ret = ptrace (PTRACE_KILL, second_pid, 0, 0);
if (ret != 0)
warning (_("linux_test_for_tracefork: failed to kill second child"));
+ my_waitpid (second_pid, &status, 0);
}
}
else
@@ -285,6 +632,8 @@ linux_test_for_tracefork (int original_pid)
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.
@@ -330,8 +679,8 @@ linux_enable_event_reporting (ptid_t ptid)
ptrace (PTRACE_SETOPTIONS, pid, 0, options);
}
-void
-child_post_attach (int pid)
+static void
+linux_child_post_attach (int pid)
{
linux_enable_event_reporting (pid_to_ptid (pid));
check_for_thread_db ();
@@ -344,20 +693,23 @@ linux_child_post_startup_inferior (ptid_t ptid)
check_for_thread_db ();
}
-int
-child_follow_fork (struct target_ops *ops, int follow_child)
+static int
+linux_child_follow_fork (struct target_ops *ops, int follow_child)
{
ptid_t last_ptid;
struct target_waitstatus last_status;
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)
{
@@ -373,7 +725,7 @@ 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,
@@ -386,6 +738,14 @@ child_follow_fork (struct target_ops *ops, int follow_child)
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)
@@ -449,7 +809,20 @@ child_follow_fork (struct target_ops *ops, int follow_child)
}
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)
@@ -458,7 +831,7 @@ 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,
@@ -466,6 +839,14 @@ child_follow_fork (struct target_ops *ops, int follow_child)
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
@@ -485,7 +866,10 @@ child_follow_fork (struct target_ops *ops, int follow_child)
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;
@@ -494,106 +878,54 @@ child_follow_fork (struct target_ops *ops, int follow_child)
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 ();
}
- return 0;
-}
-
-ptid_t
-linux_handle_extended_wait (int pid, int status,
- struct target_waitstatus *ourstatus)
-{
- int event = status >> 16;
-
- if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
- || event == PTRACE_EVENT_CLONE)
- {
- unsigned long new_pid;
- int ret;
-
- ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
-
- /* If we haven't already seen the new PID stop, wait for it now. */
- if (! pull_pid_from_list (&stopped_pids, new_pid))
- {
- /* The new child has a pending SIGSTOP. We can't affect it until it
- hits the SIGSTOP, but we're already attached. */
- ret = my_waitpid (new_pid, &status,
- (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0);
- if (ret == -1)
- perror_with_name (_("waiting for new child"));
- else if (ret != new_pid)
- internal_error (__FILE__, __LINE__,
- _("wait returned unexpected PID %d"), ret);
- else if (!WIFSTOPPED (status) || WSTOPSIG (status) != SIGSTOP)
- internal_error (__FILE__, __LINE__,
- _("wait returned unexpected status 0x%x"), status);
- }
-
- if (event == PTRACE_EVENT_FORK)
- ourstatus->kind = TARGET_WAITKIND_FORKED;
- else if (event == PTRACE_EVENT_VFORK)
- ourstatus->kind = TARGET_WAITKIND_VFORKED;
- else
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
-
- ourstatus->value.related_pid = new_pid;
- return inferior_ptid;
- }
-
- if (event == PTRACE_EVENT_EXEC)
- {
- ourstatus->kind = TARGET_WAITKIND_EXECD;
- ourstatus->value.execd_pathname
- = xstrdup (child_pid_to_exec_file (pid));
-
- if (linux_parent_pid)
- {
- detach_breakpoints (linux_parent_pid);
- ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0);
-
- linux_parent_pid = 0;
- }
-
- return inferior_ptid;
- }
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
- internal_error (__FILE__, __LINE__,
- _("unknown ptrace event %d"), event);
+ return 0;
}
-void
-child_insert_fork_catchpoint (int pid)
+static void
+linux_child_insert_fork_catchpoint (int pid)
{
if (! linux_supports_tracefork (pid))
error (_("Your system does not support fork catchpoints."));
}
-void
-child_insert_vfork_catchpoint (int pid)
+static void
+linux_child_insert_vfork_catchpoint (int pid)
{
if (!linux_supports_tracefork (pid))
error (_("Your system does not support vfork catchpoints."));
}
-void
-child_insert_exec_catchpoint (int pid)
+static void
+linux_child_insert_exec_catchpoint (int pid)
{
if (!linux_supports_tracefork (pid))
error (_("Your system does not support exec catchpoints."));
@@ -633,33 +965,12 @@ 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;
-
-
-/* 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;
@@ -667,13 +978,22 @@ 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;
/* 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 int linux_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. */
@@ -716,7 +1036,8 @@ 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)
@@ -737,6 +1058,9 @@ 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;
}
@@ -820,119 +1144,138 @@ linux_nat_switch_fork (ptid_t new_ptid)
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 && !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. */
+/* Attach to the LWP specified by PID. Return 0 if successful or -1
+ if the new LWP could not be attached. */
-void
-lin_lwp_attach_lwp (ptid_t ptid, int verbose)
+int
+lin_lwp_attach_lwp (ptid_t ptid)
{
- struct lwp_info *lp, *found_lp;
+ 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);
- }
-
- if (verbose)
- printf_filtered (_("[New %s]\n"), target_pid_to_str (ptid));
+ async_events_original_state = linux_nat_async_events (sigchld_sync);
- found_lp = lp = find_lwp_pid (ptid);
- if (lp == NULL)
- lp = add_lwp (ptid);
+ lp = find_lwp_pid (ptid);
/* We assume that we're already attached to any LWP that has an id
equal to the overall process id, and to any LWP that is already
@@ -940,34 +1283,39 @@ lin_lwp_attach_lwp (ptid_t ptid, int verbose)
and we've had PID wraparound since we last tried to stop all threads,
this assumption might be wrong; fortunately, this is very unlikely
to happen. */
- if (GET_LWP (ptid) != GET_PID (ptid) && found_lp == NULL)
+ 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)
- error (_("Can't attach %s: %s"), target_pid_to_str (ptid),
- safe_strerror (errno));
+ {
+ /* 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 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),
+ safe_strerror (errno));
+ return -1;
+ }
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)
{
@@ -981,55 +1329,223 @@ lin_lwp_attach_lwp (ptid_t ptid, int verbose)
{
/* We assume that the LWP representing the original process is
already stopped. Mark it as stopped in the data structure
- that the linux ptrace layer uses to keep track of threads.
- Note that this won't have already been done since the main
- thread will have, we assume, been stopped by an attach from a
- different layer. */
+ that the GNU/linux ptrace layer uses to keep track of
+ threads. Note that this won't have already been done since
+ the main thread will have, we assume, been stopped by an
+ attach from a different layer. */
+ if (lp == NULL)
+ lp = add_lwp (ptid);
lp->stopped = 1;
}
+
+ 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)
{
- struct lwp_info *lp;
- pid_t pid;
- int status;
+ 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);
+ }
- /* FIXME: We should probably accept a list of process id's, and
- attach all of them. */
- linux_ops->to_attach (args, from_tty);
+ /* Set SIGCHLD to the default action, until after execing the child,
+ since the inferior inherits the superior's signal mask. It will
+ be blocked again in linux_nat_wait, which is only reached after
+ the inferior execing. */
+ linux_nat_async_events (sigchld_default);
- /* 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);
+#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 */
- /* 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)
+ linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty);
+
+#ifdef HAVE_PERSONALITY
+ if (personality_set)
{
- warning (_("%s is a cloned process"), target_pid_to_str (inferior_ptid));
+ errno = 0;
+ personality (personality_orig);
+ if (errno != 0)
+ warning (_("Error restoring address space randomization: %s"),
+ safe_strerror (errno));
+ }
+#endif /* HAVE_PERSONALITY */
- /* Try again with __WCLONE to check cloned processes. */
- pid = my_waitpid (GET_PID (inferior_ptid), &status, __WCLONE);
- lp->cloned = 1;
+ 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;
+ 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 (ops, args, from_tty);
+
+ 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);
}
- 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
+get_pending_status (struct lwp_info *lp, int *status)
+{
+ struct target_waitstatus last;
+ ptid_t last_ptid;
+
+ get_last_target_status (&last_ptid, &last);
+
+ /* 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. */
+
+ *status = 0;
+
+ if (non_stop)
+ {
+ enum target_signal signo = TARGET_SIGNAL_0;
+
+ if (is_executing (lp->ptid))
+ {
+ /* If the core thought this lwp was executing --- e.g., the
+ executing property hasn't been updated yet, but the
+ thread has been stopped with a stop_callback /
+ stop_wait_callback sequence (see linux_nat_detach for
+ example) --- we can only have pending events in the local
+ queue. */
+ if (queued_waitpid (GET_LWP (lp->ptid), status, __WALL) != -1)
+ {
+ if (WIFSTOPPED (*status))
+ signo = target_signal_from_host (WSTOPSIG (*status));
+
+ /* If not stopped, then the lwp is gone, no use in
+ resending a signal. */
+ }
+ }
+ else
+ {
+ /* If the core knows the thread is not executing, then we
+ have the last signal recorded in
+ thread_info->stop_signal. */
+
+ struct thread_info *tp = find_thread_pid (lp->ptid);
+ signo = tp->stop_signal;
+ }
+
+ if (signo != TARGET_SIGNAL_0
+ && !signal_pass_state (signo))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "\
+GPT: lwp %s had signal %s, but it is in no pass state\n",
+ target_pid_to_str (lp->ptid),
+ target_signal_to_string (signo));
+ }
+ else
+ {
+ if (signo != TARGET_SIGNAL_0)
+ *status = W_STOPCODE (target_signal_to_host (signo));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "GPT: lwp %s as pending signal %s\n",
+ target_pid_to_str (lp->ptid),
+ target_signal_to_string (signo));
+ }
}
+ else
+ {
+ if (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
@@ -1042,40 +1558,30 @@ detach_callback (struct lwp_info *lp, void *data)
strsignal (WSTOPSIG (lp->status)),
target_pid_to_str (lp->ptid));
- while (lp->signalled && lp->stopped)
+ /* If there is a pending SIGSTOP, get rid of it. */
+ if (lp->signalled)
{
- 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));
-
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));
+ "DC: Sending SIGCONT to %s\n",
+ target_pid_to_str (lp->ptid));
- lp->stopped = 0;
+ kill_lwp (GET_LWP (lp->ptid), SIGCONT);
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. */
-
- gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
}
/* 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 (lp->status)) < 0)
+ WSTOPSIG (status)) < 0)
error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid),
safe_strerror (errno));
@@ -1092,24 +1598,63 @@ detach_callback (struct lwp_info *lp, void *data)
}
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. */
@@ -1119,9 +1664,8 @@ 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)),
+ linux_ops->to_resume (linux_ops,
+ pid_to_ptid (GET_LWP (lp->ptid)),
0, TARGET_SIGNAL_0);
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
@@ -1129,7 +1673,14 @@ 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));
}
+ 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;
}
@@ -1149,7 +1700,8 @@ resume_set_callback (struct lwp_info *lp, void *data)
}
static void
-linux_nat_resume (ptid_t ptid, int step, enum target_signal signo)
+linux_nat_resume (struct target_ops *ops,
+ ptid_t ptid, int step, enum target_signal signo)
{
struct lwp_info *lp;
int resume_all;
@@ -1162,15 +1714,24 @@ linux_nat_resume (ptid_t ptid, int step, enum target_signal signo)
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. */
@@ -1178,74 +1739,91 @@ 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;
+ /* 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);
+ linux_ops->to_resume (linux_ops, 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. */
@@ -1274,39 +1852,152 @@ kill_lwp (int lwpid, int signo)
return kill (lwpid, signo);
}
-/* Handle a GNU/Linux extended wait response. Most of the work we
- just pass off to linux_handle_extended_wait, but if it reports a
- clone event we need to add the new LWP to our list (and not report
- the trap to higher layers). This function returns non-zero if
- the event should be ignored and we should wait again. */
+/* Handle a GNU/Linux extended wait response. If we see a clone
+ event, we need to add the new LWP to our list (and not report the
+ trap to higher layers). This function returns non-zero if the
+ event should be ignored and we should wait again. If STOPPING is
+ true, the new LWP remains stopped, otherwise it is continued. */
static int
-linux_nat_handle_extended (struct lwp_info *lp, int status)
+linux_handle_extended_wait (struct lwp_info *lp, int status,
+ int stopping)
{
- linux_handle_extended_wait (GET_LWP (lp->ptid), status,
- &lp->waitstatus);
+ int pid = GET_LWP (lp->ptid);
+ struct target_waitstatus *ourstatus = &lp->waitstatus;
+ struct lwp_info *new_lp = NULL;
+ int event = status >> 16;
- /* TARGET_WAITKIND_SPURIOUS is used to indicate clone events. */
- if (lp->waitstatus.kind == TARGET_WAITKIND_SPURIOUS)
+ if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
+ || event == PTRACE_EVENT_CLONE)
{
- struct lwp_info *new_lp;
- new_lp = add_lwp (BUILD_LWP (lp->waitstatus.value.related_pid,
- GET_PID (inferior_ptid)));
- new_lp->cloned = 1;
- new_lp->stopped = 1;
+ unsigned long new_pid;
+ int ret;
- lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+ ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLHE: Got clone event from LWP %ld, resuming\n",
- GET_LWP (lp->ptid));
- ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ /* If we haven't already seen the new PID stop, wait for it now. */
+ if (! pull_pid_from_list (&stopped_pids, new_pid, &status))
+ {
+ /* The new child has a pending SIGSTOP. We can't affect it until it
+ hits the SIGSTOP, but we're already attached. */
+ ret = my_waitpid (new_pid, &status,
+ (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0);
+ if (ret == -1)
+ perror_with_name (_("waiting for new child"));
+ else if (ret != new_pid)
+ internal_error (__FILE__, __LINE__,
+ _("wait returned unexpected PID %d"), ret);
+ else if (!WIFSTOPPED (status))
+ internal_error (__FILE__, __LINE__,
+ _("wait returned unexpected status 0x%x"), status);
+ }
- return 1;
+ ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0);
+
+ if (event == PTRACE_EVENT_FORK)
+ ourstatus->kind = TARGET_WAITKIND_FORKED;
+ else if (event == PTRACE_EVENT_VFORK)
+ 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)
+ {
+ /* This can happen if someone starts sending signals to
+ the new thread before it gets a chance to run, which
+ have a lower number than SIGSTOP (e.g. SIGUSR1).
+ This is an unlikely case, and harder to handle for
+ fork / vfork than for clone, so we do not try - but
+ we handle it for clone events here. We'll send
+ the other signal on to the thread below. */
+
+ new_lp->signalled = 1;
+ }
+ else
+ status = 0;
+
+ 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, new_pid, 0,
+ status ? WSTOPSIG (status) : 0);
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got clone event from LWP %ld, resuming\n",
+ GET_LWP (lp->ptid));
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+
+ return 1;
+ }
+
+ return 0;
}
- return 0;
+ if (event == PTRACE_EVENT_EXEC)
+ {
+ ourstatus->kind = TARGET_WAITKIND_EXECD;
+ ourstatus->value.execd_pathname
+ = xstrdup (linux_child_pid_to_exec_file (pid));
+
+ if (linux_parent_pid)
+ {
+ detach_breakpoints (linux_parent_pid);
+ ptrace (PTRACE_DETACH, linux_parent_pid, 0, 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;
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("unknown ptrace event %d"), event);
}
/* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
@@ -1377,13 +2068,29 @@ wait_lwp (struct lwp_info *lp)
fprintf_unfiltered (gdb_stdlog,
"WL: Handling extended status 0x%06x\n",
status);
- if (linux_nat_handle_extended (lp, status))
+ if (linux_handle_extended_wait (lp, status, 1))
return wait_lwp (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
@@ -1416,43 +2123,93 @@ stop_callback (struct lwp_info *lp, void *data)
return 0;
}
-/* Wait until LP is stopped. If DATA is non-null it is interpreted as
- a pointer to a set of signals to be flushed immediately. */
+/* Return non-zero if LWP PID has a pending SIGINT. */
static int
-stop_wait_callback (struct lwp_info *lp, void *data)
+linux_nat_has_pending_sigint (int pid)
{
- sigset_t *flush_mask = data;
+ sigset_t pending, blocked, ignored;
+ int i;
- if (!lp->stopped)
- {
- int status;
+ linux_proc_pending_signals (pid, &pending, &blocked, &ignored);
- status = wait_lwp (lp);
- if (status == 0)
- return 0;
+ if (sigismember (&pending, SIGINT)
+ && !sigismember (&ignored, SIGINT))
+ return 1;
- /* Ignore any signals in FLUSH_MASK. */
- if (flush_mask && sigismember (flush_mask, WSTOPSIG (status)))
- {
- if (!lp->signalled)
- {
- lp->stopped = 1;
- return 0;
- }
+ return 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",
- target_pid_to_str (lp->ptid),
- errno ? safe_strerror (errno) : "OK");
+/* Set a flag in LP indicating that we should ignore its next SIGINT. */
- return stop_wait_callback (lp, flush_mask);
- }
+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;
- if (WSTOPSIG (status) != SIGSTOP)
+ return 0;
+}
+
+/* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
+ This function is called after we know the LWP has stopped; if the LWP
+ stopped before the expected SIGINT was delivered, then it will never have
+ arrived. Also, if the signal was delivered to a shared queue and consumed
+ by a different thread, it will never be delivered to this LWP. */
+
+static void
+maybe_clear_ignore_sigint (struct lwp_info *lp)
+{
+ if (!lp->ignore_sigint)
+ return;
+
+ if (!linux_nat_has_pending_sigint (GET_LWP (lp->ptid)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "MCIS: Clearing bogus flag for %s\n",
+ target_pid_to_str (lp->ptid));
+ lp->ignore_sigint = 0;
+ }
+}
+
+/* Wait until LP is stopped. */
+
+static int
+stop_wait_callback (struct lwp_info *lp, void *data)
+{
+ if (!lp->stopped)
+ {
+ int status;
+
+ status = wait_lwp (lp);
+ if (status == 0)
+ return 0;
+
+ if (lp->ignore_sigint && WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGINT)
+ {
+ 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) (discarding SIGINT)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ return stop_wait_callback (lp, NULL);
+ }
+
+ maybe_clear_ignore_sigint (lp);
+
+ if (WSTOPSIG (status) != SIGSTOP)
{
if (WSTOPSIG (status) == SIGTRAP)
{
@@ -1469,6 +2226,9 @@ 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);
@@ -1483,22 +2243,44 @@ 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. */
- 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);
}
- kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status));
}
- /* Save the sigtrap event. */
- lp->status = 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));
+ }
+ /* Save the sigtrap event. */
+ lp->status = status;
+ }
return 0;
}
else
@@ -1524,13 +2306,12 @@ 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
+ 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)
{
@@ -1541,6 +2322,8 @@ stop_wait_callback (struct lwp_info *lp, void *data)
}
kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
}
+ else
+ lp->status = status;
return 0;
}
}
@@ -1556,88 +2339,6 @@ stop_wait_callback (struct lwp_info *lp, void *data)
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 (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
@@ -1665,8 +2366,8 @@ count_events_callback (struct lwp_info *lp, void *data)
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)++;
@@ -1693,8 +2394,8 @@ select_event_lwp_callback (struct lwp_info *lp, void *data)
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;
@@ -1702,6 +2403,39 @@ 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. */
+
+ 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,
+ "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 (gdbarch))
+ regcache_write_pc (regcache, pc);
+
+ return 1;
+ }
+ return 0;
+}
+
static int
cancel_breakpoints_callback (struct lwp_info *lp, void *data)
{
@@ -1724,21 +2458,9 @@ 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) -
- DECR_PC_AFTER_BREAK))
- {
- 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 (DECR_PC_AFTER_BREAK)
- write_pc_pid (read_pc_pid (lp->ptid) - DECR_PC_AFTER_BREAK, lp->ptid);
-
- /* Throw away the SIGTRAP. */
- lp->status = 0;
- }
+ && cancel_breakpoint (lp))
+ /* Throw away the SIGTRAP. */
+ lp->status = 0;
return 0;
}
@@ -1826,14 +2548,255 @@ stop_and_resume_callback (struct lwp_info *lp, void *data)
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
+ on Linux 2.4, 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));
+
+ if (num_lwps > 1)
+ {
+ /* If there is at least one more LWP, then the exit signal
+ was not the end of the debugged application and should be
+ ignored. */
+ exit_lwp (lp);
+ 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_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 (linux_ops, 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 (linux_ops, 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
@@ -1842,20 +2805,17 @@ linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
{
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:
@@ -1869,6 +2829,10 @@ 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;
@@ -1879,7 +2843,7 @@ 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;
@@ -1924,7 +2888,7 @@ retry:
/* Resume the thread. It should halt immediately returning the
pending SIGSTOP. */
registers_changed ();
- linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
lp->step, TARGET_SIGNAL_0);
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
@@ -1938,15 +2902,23 @@ 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 ();
+ }
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);
@@ -1958,188 +2930,51 @@ 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)
+ lp = linux_nat_filter_event (lwpid, status, options);
+ if (!lp)
{
- linux_record_stopped_pid (lwpid);
+ /* A discarded event. */
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. */
- 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));
- }
+ break;
+ }
- /* 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_nat_handle_extended (lp, status))
- {
- status = 0;
- continue;
- }
- }
+ if (pid == -1)
+ {
+ /* Alternate between checking cloned and uncloned processes. */
+ options ^= __WCLONE;
- /* Check if the thread has exited. */
- if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
+ /* 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)
{
- /* 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))
+ if (target_can_async_p ())
{
- lp->stopped = 1;
- iterate_over_lwps (stop_and_resume_callback, NULL);
- }
+ /* No interesting event. */
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s exited.\n",
- target_pid_to_str (lp->ptid));
+ /* Get ready for the next event. */
+ target_async (inferior_event_handler, 0);
- exit_lwp (lp);
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
- /* 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;
+ return minus_one_ptid;
}
- }
-
- /* 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;
+ sigsuspend (&suspend_mask);
}
-
- /* 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. */
- status = 0;
- continue;
- }
-
- break;
- }
-
- if (pid == -1)
- {
- /* Alternate between checking cloned and uncloned processes. */
- options ^= __WCLONE;
-
- /* And suspend every time we have checked both. */
- if (options & __WCLONE)
- 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);
@@ -2153,8 +2988,18 @@ retry:
if (WIFSTOPPED (status))
{
int signo = target_signal_from_host (WSTOPSIG (status));
-
- if (signal_stop_state (signo) == 0
+ struct inferior *inf;
+
+ 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)
{
@@ -2164,7 +3009,7 @@ retry:
newly attached threads may cause an unwanted delay in
getting them running. */
registers_changed ();
- linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
lp->step, signo);
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
@@ -2178,13 +3023,23 @@ retry:
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);
}
}
@@ -2195,19 +3050,22 @@ retry:
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
@@ -2216,14 +3074,11 @@ retry:
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)
{
@@ -2233,6 +3088,13 @@ 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;
}
@@ -2267,11 +3129,18 @@ 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));
@@ -2282,11 +3151,14 @@ 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));
@@ -2296,12 +3168,15 @@ kill_wait_callback (struct lwp_info *lp, void *data)
}
static void
-linux_nat_kill (void)
+linux_nat_kill (struct target_ops *ops)
{
struct target_waitstatus last;
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. */
@@ -2311,14 +3186,24 @@ linux_nat_kill (void)
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);
@@ -2330,20 +3215,18 @@ linux_nat_kill (void)
}
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
@@ -2351,15 +3234,98 @@ linux_nat_mourn_inferior (void)
linux_fork_mourn_inferior ();
}
+/* Convert a native/host siginfo object, into/from the siginfo in the
+ layout of the inferiors' architecture. */
+
+static void
+siginfo_fixup (struct siginfo *siginfo, gdb_byte *inf_siginfo, int direction)
+{
+ int done = 0;
+
+ if (linux_nat_siginfo_fixup != NULL)
+ done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction);
+
+ /* If there was no callback, or the callback didn't do anything,
+ then just do a straight memcpy. */
+ if (!done)
+ {
+ if (direction == 1)
+ memcpy (siginfo, inf_siginfo, sizeof (struct siginfo));
+ else
+ memcpy (inf_siginfo, siginfo, sizeof (struct siginfo));
+ }
+}
+
+static LONGEST
+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_byte inf_siginfo[sizeof (struct 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;
+
+ /* When GDB is built as a 64-bit application, ptrace writes into
+ SIGINFO an object with 64-bit layout. Since debugging a 32-bit
+ inferior with a 64-bit GDB should look the same as debugging it
+ with a 32-bit GDB, we need to convert it. GDB core always sees
+ the converted layout, so any read/write will have to be done
+ post-conversion. */
+ siginfo_fixup (&siginfo, inf_siginfo, 0);
+
+ if (offset + len > sizeof (siginfo))
+ len = sizeof (siginfo) - offset;
+
+ if (readbuf != NULL)
+ memcpy (readbuf, inf_siginfo + offset, len);
+ else
+ {
+ memcpy (inf_siginfo + offset, writebuf, len);
+
+ /* Convert back to ptrace layout before flushing it out. */
+ siginfo_fixup (&siginfo, inf_siginfo, 1);
+
+ 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 = save_inferior_ptid ();
+ 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));
@@ -2371,35 +3337,43 @@ linux_nat_xfer_partial (struct target_ops *ops, enum target_object object,
}
static int
-linux_nat_thread_alive (ptid_t ptid)
+linux_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 target 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 int
+linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid)
+{
+ return linux_thread_alive (ptid);
+}
+
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;
@@ -2411,6 +3385,13 @@ linux_nat_pid_to_str (ptid_t ptid)
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. */
@@ -2419,8 +3400,8 @@ sigchld_handler (int signo)
/* Accepts an integer PID; Returns a string representing a file that
can be opened to get the symbols for the child process. */
-char *
-child_pid_to_exec_file (int pid)
+static char *
+linux_child_pid_to_exec_file (int pid)
{
char *name1, *name2;
@@ -2474,18 +3455,20 @@ linux_nat_find_memory_regions (int (*func) (CORE_ADDR,
unsigned long,
int, int, int, void *), void *obfd)
{
- long long pid = PIDGET (inferior_ptid);
+ int pid = PIDGET (inferior_ptid);
char mapsfilename[MAXPATHLEN];
FILE *mapsfile;
long long addr, endaddr, size, offset, inode;
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);
+ sprintf (mapsfilename, "/proc/%d/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,
@@ -2509,7 +3492,7 @@ linux_nat_find_memory_regions (int (*func) (CORE_ADDR,
size, paddr_nz (addr),
read ? 'r' : ' ',
write ? 'w' : ' ', exec ? 'x' : ' ');
- if (filename && filename[0])
+ if (filename[0])
fprintf_filtered (gdb_stdout, " for %s", filename);
fprintf_filtered (gdb_stdout, "\n");
}
@@ -2518,43 +3501,124 @@ linux_nat_find_memory_regions (int (*func) (CORE_ADDR,
segment. */
func (addr, size, read, write, exec, obfd);
}
- fclose (mapsfile);
+ do_cleanups (cleanup);
return 0;
}
+static int
+find_signalled_thread (struct thread_info *info, void *data)
+{
+ if (info->stop_signal != TARGET_SIGNAL_0
+ && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
+ return 1;
+
+ return 0;
+}
+
+static enum target_signal
+find_stop_signal (void)
+{
+ struct thread_info *info =
+ iterate_over_threads (find_signalled_thread, NULL);
+
+ if (info)
+ return info->stop_signal;
+ else
+ return TARGET_SIGNAL_0;
+}
+
/* Records the thread's register state for the corefile note
section. */
static char *
linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid,
- char *note_data, int *note_size)
+ char *note_data, int *note_size,
+ enum target_signal stop_signal)
{
gdb_gregset_t gregs;
gdb_fpregset_t fpregs;
-#ifdef FILL_FPXREGSET
- gdb_fpxregset_t fpxregs;
-#endif
unsigned long lwp = ptid_get_lwp (ptid);
+ struct regcache *regcache = get_thread_regcache (ptid);
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ const struct regset *regset;
+ int core_regset_p;
+ struct cleanup *old_chain;
+ struct core_regset_section *sect_list;
+ char *gdb_regset;
+
+ old_chain = save_inferior_ptid ();
+ inferior_ptid = ptid;
+ 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, regcache, -1,
+ &gregs, sizeof (gregs));
+ else
+ fill_gregset (regcache, &gregs, -1);
- fill_gregset (&gregs, -1);
note_data = (char *) elfcore_write_prstatus (obfd,
note_data,
note_size,
lwp,
stop_signal, &gregs);
- fill_fpregset (&fpregs, -1);
- note_data = (char *) elfcore_write_prfpreg (obfd,
- note_data,
- note_size,
- &fpregs, sizeof (fpregs));
-#ifdef FILL_FPXREGSET
- fill_fpxregset (&fpxregs, -1);
- note_data = (char *) elfcore_write_prxfpreg (obfd,
- note_data,
- note_size,
- &fpxregs, sizeof (fpxregs));
-#endif
+ /* 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++;
+ }
+
+ /* 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
+ {
+ 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));
+ }
+
return note_data;
}
@@ -2564,6 +3628,7 @@ struct linux_nat_corefile_thread_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
@@ -2573,39 +3638,15 @@ static int
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 ();
- target_fetch_registers (-1); /* FIXME should not be necessary;
- fill_gregset should do it automatically. */
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 ();
- target_fetch_registers (-1); /* FIXME should not be necessary;
- fill_gregset should do it automatically. */
- 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 ();
- target_fetch_registers (-1); /* FIXME should not be necessary;
- fill_gregset should do it automatically. */
- 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;
+ return 0;
}
/* Fills the "to_make_corefile_note" target vector. Builds the note
@@ -2616,7 +3657,9 @@ 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;
@@ -2629,9 +3672,18 @@ 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,
@@ -2643,20 +3695,13 @@ linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
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_auxv_read (¤t_target, &auxv);
+ auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV,
+ NULL, &auxv);
if (auxv_len > 0)
{
note_data = elfcore_write_note (obfd, note_data, note_size,
@@ -2673,7 +3718,9 @@ linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
static void
linux_nat_info_proc_cmd (char *args, int from_tty)
{
- long long pid = PIDGET (inferior_ptid);
+ /* A long is used for pid instead of an int to avoid a loss of precision
+ compiler warning from the output of strtoul. */
+ long pid = PIDGET (inferior_ptid);
FILE *procfile;
char **argv = NULL;
char buffer[MAXPATHLEN];
@@ -2691,10 +3738,8 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
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)
{
@@ -2739,26 +3784,29 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
if (pid == 0)
error (_("No current process: you must name one."));
- sprintf (fname1, "/proc/%lld", pid);
+ sprintf (fname1, "/proc/%ld", pid);
if (stat (fname1, &dummy) != 0)
error (_("No /proc directory: '%s'"), fname1);
- printf_filtered (_("process %lld\n"), pid);
+ printf_filtered (_("process %ld\n"), pid);
if (cmdline_f || all)
{
- sprintf (fname1, "/proc/%lld/cmdline", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ sprintf (fname1, "/proc/%ld/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);
}
if (cwd_f || all)
{
- sprintf (fname1, "/proc/%lld/cwd", pid);
+ sprintf (fname1, "/proc/%ld/cwd", pid);
memset (fname2, 0, sizeof (fname2));
if (readlink (fname1, fname2, sizeof (fname2)) > 0)
printf_filtered ("cwd = '%s'\n", fname2);
@@ -2767,7 +3815,7 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
}
if (exe_f || all)
{
- sprintf (fname1, "/proc/%lld/exe", pid);
+ sprintf (fname1, "/proc/%ld/exe", pid);
memset (fname2, 0, sizeof (fname2));
if (readlink (fname1, fname2, sizeof (fname2)) > 0)
printf_filtered ("exe = '%s'\n", fname2);
@@ -2776,14 +3824,16 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
}
if (mappings_f || all)
{
- sprintf (fname1, "/proc/%lld/maps", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ sprintf (fname1, "/proc/%ld/maps", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
{
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 (TARGET_ADDR_BIT == 32)
+ if (gdbarch_addr_bit (current_gdbarch) == 32)
{
printf_filtered ("\t%10s %10s %10s %10s %7s\n",
"Start Addr",
@@ -2809,7 +3859,7 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
a generic local_address_string instead to print out
the addresses; that makes sense to me, too. */
- if (TARGET_ADDR_BIT == 32)
+ if (gdbarch_addr_bit (current_gdbarch) == 32)
{
printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
(unsigned long) addr, /* FIXME: pr_addr */
@@ -2829,34 +3879,37 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
}
}
- fclose (procfile);
+ do_cleanups (cleanup);
}
else
warning (_("unable to open /proc file '%s'"), fname1);
}
if (status_f || all)
{
- sprintf (fname1, "/proc/%lld/status", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ sprintf (fname1, "/proc/%ld/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);
}
if (stat_f || all)
{
- sprintf (fname1, "/proc/%lld/stat", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ sprintf (fname1, "/proc/%ld/stat", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
{
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);
@@ -2870,73 +3923,73 @@ 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);
+ do_cleanups (cleanup);
}
else
warning (_("unable to open /proc file '%s'"), fname1);
@@ -3038,6 +4091,7 @@ linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigse
FILE *procfile;
char buffer[MAXPATHLEN], fname[MAXPATHLEN];
int signum;
+ struct cleanup *cleanup;
sigemptyset (pending);
sigemptyset (blocked);
@@ -3046,6 +4100,7 @@ linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigse
procfile = fopen (fname, "r");
if (procfile == NULL)
error (_("Could not open %s"), fname);
+ cleanup = make_cleanup_fclose (procfile);
while (fgets (buffer, MAXPATHLEN, procfile) != NULL)
{
@@ -3067,7 +4122,114 @@ linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigse
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, "\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])
+ || NAMELEN (dp) > 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,
+ "- "
+ "%s"
+ "%s"
+ "%s"
+ "
",
+ dp->d_name,
+ entry ? entry->pw_name : "?",
+ cmd);
+ }
+ fclose (f);
+ }
+
+ xfree (pathname);
+ }
+ }
+
+ closedir (dirp);
+ }
+
+ obstack_grow_str0 (&obstack, "\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
@@ -3081,6 +4243,10 @@ linux_xfer_partial (struct target_ops *ops, enum target_object object,
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)
@@ -3090,56 +4256,474 @@ linux_xfer_partial (struct target_ops *ops, enum target_object object,
offset, len);
}
-#ifndef FETCH_INFERIOR_REGISTERS
-
-/* Return the address in the core dump or inferior of register
- REGNO. */
+/* Create a prototype generic GNU/Linux target. The client can override
+ it with local methods. */
-static CORE_ADDR
-linux_register_u_offset (int regno)
+static void
+linux_target_install_ops (struct target_ops *t)
{
- /* FIXME drow/2005-09-04: The hardcoded use of register_addr should go
- away. This requires disentangling the various definitions of it
- (particularly alpha-nat.c's). */
- return register_addr (regno, 0);
-}
-
-#endif
+ t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint;
+ t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint;
+ t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint;
+ t->to_pid_to_exec_file = linux_child_pid_to_exec_file;
+ t->to_post_startup_inferior = linux_child_post_startup_inferior;
+ t->to_post_attach = linux_child_post_attach;
+ t->to_follow_fork = linux_child_follow_fork;
+ t->to_find_memory_regions = linux_nat_find_memory_regions;
+ t->to_make_corefile_notes = linux_nat_make_corefile_notes;
-/* Create a prototype generic Linux target. The client can override
- it with local methods. */
+ super_xfer_partial = t->to_xfer_partial;
+ t->to_xfer_partial = linux_xfer_partial;
+}
struct target_ops *
linux_target (void)
{
struct target_ops *t;
-#ifdef FETCH_INFERIOR_REGISTERS
t = inf_ptrace_target ();
-#else
- t = inf_ptrace_trad_target (linux_register_u_offset);
-#endif
- t->to_insert_fork_catchpoint = child_insert_fork_catchpoint;
- t->to_insert_vfork_catchpoint = child_insert_vfork_catchpoint;
- t->to_insert_exec_catchpoint = child_insert_exec_catchpoint;
- t->to_pid_to_exec_file = child_pid_to_exec_file;
- t->to_post_startup_inferior = linux_child_post_startup_inferior;
- t->to_post_attach = child_post_attach;
- t->to_follow_fork = child_follow_fork;
- t->to_find_memory_regions = linux_nat_find_memory_regions;
- t->to_make_corefile_notes = linux_nat_make_corefile_notes;
+ linux_target_install_ops (t);
- super_xfer_partial = t->to_xfer_partial;
- t->to_xfer_partial = linux_xfer_partial;
+ return t;
+}
+
+struct target_ops *
+linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int))
+{
+ struct target_ops *t;
+
+ t = inf_ptrace_trad_target (register_u_offset);
+ linux_target_install_ops (t);
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. */
+
+static 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)
{
- extern void thread_db_init (struct target_ops *);
-
/* Save the provided single-threaded target. We save this in a separate
variable because another target we've inherited from (e.g. inf-ptrace)
may have saved a pointer to T; we want to use it for the final
@@ -3148,6 +4732,7 @@ 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;
@@ -3159,6 +4744,17 @@ 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_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
@@ -3166,16 +4762,61 @@ linux_nat_add_target (struct target_ops *t)
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;
+}
+
+/* Register a method that converts a siginfo object between the layout
+ that ptrace returns, and the layout in the architecture of the
+ inferior. */
+void
+linux_nat_set_siginfo_fixup (struct target_ops *t,
+ int (*siginfo_fixup) (struct siginfo *,
+ gdb_byte *,
+ int))
+{
+ /* Save the pointer. */
+ linux_nat_siginfo_fixup = siginfo_fixup;
+}
+
+/* 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;
+}
+
+/* Enable/Disable async mode. */
- /* TODO: Eliminate this and have libthread_db use
- find_target_beneath. */
- thread_db_init (t);
+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);
}
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_linux_nat;
+
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\
@@ -3186,27 +4827,67 @@ 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);
+
+ /* 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);
}
@@ -3242,7 +4923,9 @@ 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");
@@ -3280,4 +4963,3 @@ lin_thread_get_thread_signals (sigset_t *set)
/* ... except during a sigsuspend. */
sigdelset (&suspend_mask, cancel);
}
-