X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Flinux-nat.c;h=b09cd498960283d0b8f3dc8296756a4a40777096;hb=604133b5c51154a435f50cc079b24cb2f2eb8770;hp=80b0cfff70c5012aad279bb07b470015b1188a69;hpb=85c078043bd43ef5cb76191a6d3e2159da0c302e;p=deliverable%2Fbinutils-gdb.git
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index 80b0cfff70..b09cd49896 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -1,12 +1,13 @@
/* GNU/Linux native-dependent code common to multiple platforms.
- Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
+ Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
@@ -15,9 +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., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see . */
#include "defs.h"
#include "inferior.h"
@@ -31,9 +30,13 @@
#endif
#include
#include "linux-nat.h"
+#include "linux-fork.h"
#include "gdbthread.h"
#include "gdbcmd.h"
#include "regcache.h"
+#include "regset.h"
+#include "inf-ptrace.h"
+#include "auxv.h"
#include /* for MAXPATHLEN */
#include /* for elf_gregset etc. */
#include "elf-bfd.h" /* for elfcore_write_* */
@@ -43,6 +46,33 @@
#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"
+
+/* Note on this file's use of signals:
+
+ We stop threads by sending a SIGSTOP. The use of SIGSTOP instead
+ of another signal is not entirely significant; we just need for a
+ signal to be delivered, so that we can intercept it. SIGSTOP's
+ advantage is that it can not be blocked. A disadvantage is that it
+ is not a real-time signal, so it can only be queued once; we do not
+ keep track of other sources of SIGSTOP.
+
+ Two other signals that can't be blocked are SIGCONT and SIGKILL.
+ But we can't use them, because they have special behavior when the
+ signal is generated - not when it is delivered. SIGCONT resumes
+ the entire thread group and SIGKILL kills the entire thread group.
+
+ A delivered SIGSTOP would stop the entire thread group, not just the
+ thread we tkill'd. But we never let the SIGSTOP deliver; we always
+ intercept and cancel it (by PTRACE_CONT without passing SIGSTOP).
+
+ We could use a real-time signal instead. This would solve those
+ problems; we could use PTRACE_GETSIGINFO to locate the specific
+ stop signals sent by GDB. But we would still have to have some
+ support for SIGSTOP, since PTRACE_ATTACH generates it, and there
+ are races with trying to find a signal that is not blocked. */
#ifndef O_LARGEFILE
#define O_LARGEFILE 0
@@ -81,13 +111,50 @@
#define __WALL 0x40000000 /* Wait for any child. */
#endif
+#ifndef PTRACE_GETSIGINFO
+#define PTRACE_GETSIGINFO 0x4202
+#endif
+
+/* The single-threaded native GNU/Linux target_ops. We save a pointer for
+ the use of the multi-threaded target. */
+static struct target_ops *linux_ops;
+static struct target_ops linux_ops_saved;
+
+/* The method to call, if any, when a new thread is attached. */
+static void (*linux_nat_new_thread) (ptid_t);
+
+/* The saved to_xfer_partial method, inherited from inf-ptrace.c.
+ Called by our to_xfer_partial. */
+static LONGEST (*super_xfer_partial) (struct target_ops *,
+ enum target_object,
+ const char *, gdb_byte *,
+ const gdb_byte *,
+ ULONGEST, LONGEST);
+
static int debug_linux_nat;
+static void
+show_debug_linux_nat (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"),
+ value);
+}
+
+static int debug_linux_nat_async = 0;
+static void
+show_debug_linux_nat_async (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("Debugging of GNU/Linux async lwp module is %s.\n"),
+ value);
+}
static int linux_parent_pid;
struct simple_pid_list
{
int pid;
+ int status;
struct simple_pid_list *next;
};
struct simple_pid_list *stopped_pids;
@@ -102,20 +169,174 @@ static int linux_supports_tracefork_flag = -1;
static int linux_supports_tracevforkdone_flag = -1;
+/* Async mode support */
+
+/* To listen to target events asynchronously, we install a SIGCHLD
+ handler whose duty is to call waitpid (-1, ..., WNOHANG) to get all
+ the pending events into a pipe. Whenever we're ready to handle
+ events asynchronously, this pipe is registered as the waitable file
+ handle in the event loop. When we get to entry target points
+ coming out of the common code (target_wait, target_resume, ...),
+ that are going to call waitpid, we block SIGCHLD signals, and
+ remove all the events placed in the pipe into a local queue. All
+ the subsequent calls to my_waitpid (a waitpid wrapper) check this
+ local queue first. */
+
+/* True if async mode is currently on. */
+static int linux_nat_async_enabled;
+
+/* Zero if the async mode, although enabled, is masked, which means
+ linux_nat_wait should behave as if async mode was off. */
+static int linux_nat_async_mask_value = 1;
+
+/* The read/write ends of the pipe registered as waitable file in the
+ event loop. */
+static int linux_nat_event_pipe[2] = { -1, -1 };
+
+/* Number of queued events in the pipe. */
+static volatile int linux_nat_num_queued_events;
+
+/* If async mode is on, true if we're listening for events; false if
+ target events are blocked. */
+static int linux_nat_async_events_enabled;
+
+static int linux_nat_async_events (int enable);
+static void pipe_to_local_event_queue (void);
+static void local_event_queue_to_pipe (void);
+static void linux_nat_event_pipe_push (int pid, int status, int options);
+static int linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options);
+static void linux_nat_set_async_mode (int on);
+static void linux_nat_async (void (*callback)
+ (enum inferior_event_type event_type, void *context),
+ void *context);
+static int linux_nat_async_mask (int mask);
+static int kill_lwp (int lwpid, int signo);
+
+/* Captures the result of a successful waitpid call, along with the
+ options used in that call. */
+struct waitpid_result
+{
+ int pid;
+ int status;
+ int options;
+ struct waitpid_result *next;
+};
+
+/* A singly-linked list of the results of the waitpid calls performed
+ in the async SIGCHLD handler. */
+static struct waitpid_result *waitpid_queue = NULL;
+
+static int
+queued_waitpid (int pid, int *status, int flags)
+{
+ struct waitpid_result *msg = waitpid_queue, *prev = NULL;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "\
+QWPID: linux_nat_async_events_enabled(%d), linux_nat_num_queued_events(%d)\n",
+ linux_nat_async_events_enabled,
+ linux_nat_num_queued_events);
+
+ if (flags & __WALL)
+ {
+ for (; msg; prev = msg, msg = msg->next)
+ if (pid == -1 || pid == msg->pid)
+ break;
+ }
+ else if (flags & __WCLONE)
+ {
+ for (; msg; prev = msg, msg = msg->next)
+ if (msg->options & __WCLONE
+ && (pid == -1 || pid == msg->pid))
+ break;
+ }
+ else
+ {
+ for (; msg; prev = msg, msg = msg->next)
+ if ((msg->options & __WCLONE) == 0
+ && (pid == -1 || pid == msg->pid))
+ break;
+ }
+
+ if (msg)
+ {
+ int pid;
+
+ if (prev)
+ prev->next = msg->next;
+ else
+ waitpid_queue = msg->next;
+
+ msg->next = NULL;
+ if (status)
+ *status = msg->status;
+ pid = msg->pid;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "QWPID: pid(%d), status(%x)\n",
+ pid, msg->status);
+ xfree (msg);
+
+ return pid;
+ }
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "QWPID: miss\n");
+
+ if (status)
+ *status = 0;
+ return -1;
+}
+
+static void
+push_waitpid (int pid, int status, int options)
+{
+ struct waitpid_result *event, *new_event;
+
+ new_event = xmalloc (sizeof (*new_event));
+ new_event->pid = pid;
+ new_event->status = status;
+ new_event->options = options;
+ new_event->next = NULL;
+
+ if (waitpid_queue)
+ {
+ for (event = waitpid_queue;
+ event && event->next;
+ event = event->next)
+ ;
+
+ event->next = new_event;
+ }
+ else
+ waitpid_queue = new_event;
+}
+
+/* Drain all queued events of PID. If PID is -1, the effect is of
+ draining all events. */
+static void
+drain_queued_events (int pid)
+{
+ while (queued_waitpid (pid, NULL, __WALL) != -1)
+ ;
+}
+
/* Trivial list manipulation functions to keep track of a list of
new stopped processes. */
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;
@@ -123,6 +344,7 @@ 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;
@@ -130,10 +352,10 @@ 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);
}
@@ -150,12 +372,21 @@ linux_tracefork_child (void)
_exit (0);
}
-/* Wrapper function for waitpid which handles EINTR. */
+/* Wrapper function for waitpid which handles EINTR, and checks for
+ locally queued events. */
static int
my_waitpid (int pid, int *status, int flags)
{
int ret;
+
+ /* There should be no concurrent calls to waitpid. */
+ gdb_assert (!linux_nat_async_events_enabled);
+
+ ret = queued_waitpid (pid, status, flags);
+ if (ret != -1)
+ return ret;
+
do
{
ret = waitpid (pid, status, flags);
@@ -251,6 +482,7 @@ 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
@@ -286,9 +518,12 @@ linux_supports_tracevforkdone (int pid)
void
linux_enable_event_reporting (ptid_t ptid)
{
- int pid = ptid_get_pid (ptid);
+ int pid = ptid_get_lwp (ptid);
int options;
+ if (pid == 0)
+ pid = ptid_get_pid (ptid);
+
if (! linux_supports_tracefork (pid))
return;
@@ -303,37 +538,36 @@ 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 ();
}
-void
+static void
linux_child_post_startup_inferior (ptid_t ptid)
{
linux_enable_event_reporting (ptid);
+ check_for_thread_db ();
}
-#ifndef LINUX_CHILD_POST_STARTUP_INFERIOR
-void
-child_post_startup_inferior (ptid_t ptid)
-{
- linux_child_post_startup_inferior (ptid);
-}
-#endif
-
-int
-child_follow_fork (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_pid (last_ptid);
+ 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;
if (! follow_child)
@@ -347,11 +581,28 @@ child_follow_fork (int follow_child)
also, but they'll be reinserted below. */
detach_breakpoints (child_pid);
- fprintf_filtered (gdb_stdout,
- "Detaching after fork from child process %d.\n",
- child_pid);
+ /* Detach new forked process? */
+ if (detach_fork)
+ {
+ if (info_verbose || debug_linux_nat)
+ {
+ target_terminal_ours ();
+ fprintf_filtered (gdb_stdlog,
+ "Detaching after fork from child process %d.\n",
+ child_pid);
+ }
- ptrace (PTRACE_DETACH, child_pid, 0, 0);
+ ptrace (PTRACE_DETACH, child_pid, 0, 0);
+ }
+ else
+ {
+ struct fork_info *fp;
+ /* Retain child fork in ptrace (stopped) state. */
+ fp = find_fork_pid (child_pid);
+ if (!fp)
+ fp = add_fork (child_pid);
+ fork_save_infrun_state (fp, 0);
+ }
if (has_vforked)
{
@@ -361,7 +612,7 @@ child_follow_fork (int follow_child)
int status;
ptrace (PTRACE_CONT, parent_pid, 0, 0);
- waitpid (parent_pid, &status, __WALL);
+ my_waitpid (parent_pid, &status, __WALL);
if ((status >> 16) != PTRACE_EVENT_VFORK_DONE)
warning (_("Unexpected waitpid result %06x when waiting for "
"vfork-done"), status);
@@ -418,9 +669,13 @@ child_follow_fork (int follow_child)
/* Before detaching from the parent, remove all breakpoints from it. */
remove_breakpoints ();
- fprintf_filtered (gdb_stdout,
- "Attaching after fork to child process %d.\n",
- child_pid);
+ if (info_verbose || debug_linux_nat)
+ {
+ target_terminal_ours ();
+ fprintf_filtered (gdb_stdlog,
+ "Attaching after fork to child process %d.\n",
+ child_pid);
+ }
/* 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
@@ -442,147 +697,59 @@ child_follow_fork (int follow_child)
if (has_vforked)
linux_parent_pid = parent_pid;
- else
- target_detach (NULL, 0);
-
- inferior_ptid = pid_to_ptid (child_pid);
- push_target (&deprecated_child_ops);
-
- /* 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))
+ else if (!detach_fork)
{
- /* The new child has a pending SIGSTOP. We can't affect it until it
- hits the SIGSTOP, but we're already attached. */
- do {
- ret = waitpid (new_pid, &status,
- (event == PTRACE_EVENT_CLONE) ? __WCLONE : 0);
- } while (ret == -1 && errno == EINTR);
- 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);
+ struct fork_info *fp;
+ /* Retain parent fork in ptrace (stopped) state. */
+ fp = find_fork_pid (parent_pid);
+ if (!fp)
+ fp = add_fork (parent_pid);
+ fork_save_infrun_state (fp, 0);
}
-
- 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;
- }
+ target_detach (NULL, 0);
- if (event == PTRACE_EVENT_EXEC)
- {
- ourstatus->kind = TARGET_WAITKIND_EXECD;
- ourstatus->value.execd_pathname
- = xstrdup (child_pid_to_exec_file (pid));
+ inferior_ptid = ptid_build (child_pid, child_pid, 0);
- if (linux_parent_pid)
- {
- detach_breakpoints (linux_parent_pid);
- ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0);
+ /* Reinstall ourselves, since we might have been removed in
+ target_detach (which does other necessary cleanup). */
- linux_parent_pid = 0;
- }
+ push_target (ops);
+ linux_nat_switch_fork (inferior_ptid);
+ check_for_thread_db ();
- return inferior_ptid;
+ /* Reset breakpoints in the child as appropriate. */
+ follow_inferior_reset_breakpoints ();
}
- internal_error (__FILE__, __LINE__,
- _("unknown ptrace event %d"), event);
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+
+ 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."));
}
-void
-kill_inferior (void)
-{
- int status;
- int pid = PIDGET (inferior_ptid);
- struct target_waitstatus last;
- ptid_t last_ptid;
- int ret;
-
- if (pid == 0)
- return;
-
- /* 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. */
-
- get_last_target_status (&last_ptid, &last);
-
- if (last.kind == TARGET_WAITKIND_FORKED
- || last.kind == TARGET_WAITKIND_VFORKED)
- {
- ptrace (PT_KILL, last.value.related_pid, 0, 0);
- wait (&status);
- }
-
- /* Kill the current process. */
- ptrace (PT_KILL, pid, 0, 0);
- ret = wait (&status);
-
- /* We might get a SIGCHLD instead of an exit status. This is
- aggravated by the first kill above - a child has just died. */
-
- while (ret == pid && WIFSTOPPED (status))
- {
- ptrace (PT_KILL, pid, 0, 0);
- ret = wait (&status);
- }
-
- target_mourn_inferior ();
-}
-
/* On GNU/Linux there are no real LWP's. The closest thing to LWP's
are processes sharing the same VM space. A multi-threaded process
is basically a group of such processes. However, such a grouping
@@ -617,28 +784,17 @@ kill_inferior (void)
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;
-
-/* Non-zero if we're running in "threaded" mode. */
-static int threaded;
-#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;
-/* This module's target-specific operations. */
-static struct target_ops linux_nat_ops;
-
/* 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
@@ -657,13 +813,19 @@ static sigset_t normal_mask;
_initialize_linux_nat. */
static sigset_t suspend_mask;
-/* Signals to block to make that sigsuspend work. */
-static sigset_t blocked_mask;
+/* SIGCHLD action for synchronous mode. */
+struct sigaction sync_sigchld_action;
+
+/* SIGCHLD action for asynchronous mode. */
+static struct sigaction async_sigchld_action;
/* Prototypes for local functions. */
static int stop_wait_callback (struct lwp_info *lp, void *data);
static int linux_nat_thread_alive (ptid_t ptid);
+static char *linux_child_pid_to_exec_file (int pid);
+static int cancel_breakpoint (struct lwp_info *lp);
+
/* Convert wait status STATUS to a string. Used for printing debug
messages only. */
@@ -703,12 +865,11 @@ init_lwp_list (void)
lwp_list = NULL;
num_lwps = 0;
- threaded = 0;
}
-/* Add the LWP specified by PID to the list. If this causes the
- number of LWPs to become larger than one, go into "threaded" mode.
- Return a pointer to the structure describing the new LWP. */
+/* Add the LWP specified by PID to the list. Return a pointer to the
+ 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)
@@ -727,8 +888,10 @@ add_lwp (ptid_t ptid)
lp->next = lwp_list;
lwp_list = lp;
- if (++num_lwps > 1)
- threaded = 1;
+ ++num_lwps;
+
+ if (num_lwps > 1 && linux_nat_new_thread != NULL)
+ linux_nat_new_thread (ptid);
return lp;
}
@@ -749,8 +912,6 @@ delete_lwp (ptid_t ptid)
if (!lp)
return;
- /* We don't go back to "non-threaded" mode if the number of threads
- becomes less than two. */
num_lwps--;
if (lpprev)
@@ -802,129 +963,364 @@ iterate_over_lwps (int (*callback) (struct lwp_info *, void *), void *data)
return NULL;
}
-/* 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. */
+/* Update our internal state when changing from one fork (checkpoint,
+ et cetera) to another indicated by NEW_PTID. We can only switch
+ single-threaded applications, so we only create one new LWP, and
+ the previous list is discarded. */
void
-lin_lwp_attach_lwp (ptid_t ptid, int verbose)
+linux_nat_switch_fork (ptid_t new_ptid)
{
- struct lwp_info *lp, *found_lp;
+ struct lwp_info *lp;
- gdb_assert (is_lwp (ptid));
+ init_lwp_list ();
+ lp = add_lwp (new_ptid);
+ lp->stopped = 1;
+}
- /* 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);
- }
+/* Record a PTID for later deletion. */
- if (verbose)
- printf_filtered (_("[New %s]\n"), target_pid_to_str (ptid));
+struct saved_ptids
+{
+ ptid_t ptid;
+ struct saved_ptids *next;
+};
+static struct saved_ptids *threads_to_delete;
- found_lp = lp = find_lwp_pid (ptid);
- if (lp == NULL)
- lp = add_lwp (ptid);
+static void
+record_dead_thread (ptid_t ptid)
+{
+ struct saved_ptids *p = xmalloc (sizeof (struct saved_ptids));
+ p->ptid = ptid;
+ p->next = threads_to_delete;
+ threads_to_delete = p;
+}
- /* 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
- in our list of LWPs. If we're not seeing exit events from threads
- 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)
- {
- pid_t pid;
- int status;
+/* Delete any dead threads which are not the current thread. */
- if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
- error (_("Can't attach %s: %s"), target_pid_to_str (ptid),
- safe_strerror (errno));
+static void
+prune_lwps (void)
+{
+ struct saved_ptids **p = &threads_to_delete;
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
- target_pid_to_str (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;
+}
- pid = waitpid (GET_LWP (ptid), &status, 0);
- if (pid == -1 && errno == ECHILD)
- {
- /* Try again with __WCLONE to check cloned processes. */
- pid = waitpid (GET_LWP (ptid), &status, __WCLONE);
- lp->cloned = 1;
- }
+/* Handle the exit of a single thread LP. */
+
+static void
+exit_lwp (struct lwp_info *lp)
+{
+ if (in_thread_list (lp->ptid))
+ {
+ if (print_thread_events)
+ printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid));
- gdb_assert (pid == GET_LWP (ptid)
- && WIFSTOPPED (status) && WSTOPSIG (status));
+ /* 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);
+ }
- child_post_attach (pid);
+ delete_lwp (lp->ptid);
+}
- lp->stopped = 1;
+/* Detect `T (stopped)' in `/proc/PID/status'.
+ Other states including `T (tracing stop)' are reported as false. */
- if (debug_linux_nat)
+static int
+pid_is_stopped (pid_t pid)
+{
+ FILE *status_file;
+ char buf[100];
+ int retval = 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))
{
- fprintf_unfiltered (gdb_stdlog,
- "LLAL: waitpid %s received %s\n",
- target_pid_to_str (ptid),
- status_to_str (status));
+ if (strncmp (buf, "State:", 6) == 0)
+ {
+ have_state = 1;
+ break;
+ }
}
+ if (have_state && strstr (buf, "T (stopped)") != NULL)
+ retval = 1;
+ fclose (status_file);
}
- else
- {
- /* 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. */
- lp->stopped = 1;
- }
+ return retval;
}
-static void
-linux_nat_attach (char *args, int from_tty)
+/* Wait for the LWP specified by LP, which we have just attached to.
+ Returns a wait status for that LWP, to cache. */
+
+static int
+linux_nat_post_attach_wait (ptid_t ptid, int first, int *cloned,
+ int *signalled)
{
- struct lwp_info *lp;
- pid_t pid;
+ pid_t new_pid, pid = GET_LWP (ptid);
int status;
- /* FIXME: We should probably accept a list of process id's, and
- attach all of them. */
- deprecated_child_ops.to_attach (args, from_tty);
-
- /* Add the initial process as the first LWP to the list. */
- lp = add_lwp (BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid)));
+ if (pid_is_stopped (pid))
+ {
+ 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);
+ }
/* 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 = waitpid (GET_PID (inferior_ptid), &status, 0);
- if (pid == -1 && errno == ECHILD)
+ new_pid = my_waitpid (pid, &status, 0);
+ if (new_pid == -1 && errno == ECHILD)
{
- warning (_("%s is a cloned process"), target_pid_to_str (inferior_ptid));
+ if (first)
+ warning (_("%s is a cloned process"), target_pid_to_str (ptid));
/* Try again with __WCLONE to check cloned processes. */
- pid = waitpid (GET_PID (inferior_ptid), &status, __WCLONE);
- lp->cloned = 1;
+ new_pid = my_waitpid (pid, &status, __WCLONE);
+ *cloned = 1;
+ }
+
+ 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));
+ }
+
+ return status;
+}
+
+/* Attach to the LWP specified by PID. Return 0 if successful or -1
+ if the new LWP could not be attached. */
+
+int
+lin_lwp_attach_lwp (ptid_t ptid)
+{
+ struct lwp_info *lp;
+ int async_events_were_enabled = 0;
+
+ gdb_assert (is_lwp (ptid));
+
+ if (target_can_async_p ())
+ async_events_were_enabled = linux_nat_async_events (0);
+
+ 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
+ in our list of LWPs. If we're not seeing exit events from threads
+ 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) && lp == NULL)
+ {
+ int status, cloned = 0, signalled = 0;
+
+ if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
+ {
+ /* If we fail to attach to the thread, issue a warning,
+ but continue. One way this can happen is if thread
+ creation is interrupted; as of Linux 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));
+
+ 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)
+ {
+ lp->resumed = 1;
+ lp->status = status;
+ }
+
+ target_post_attach (GET_LWP (lp->ptid));
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "LLAL: waitpid %s received %s\n",
+ target_pid_to_str (ptid),
+ status_to_str (status));
+ }
}
+ else
+ {
+ /* We assume that the LWP representing the original process is
+ already stopped. Mark it as stopped in the data structure
+ 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;
+ }
+
+ if (async_events_were_enabled)
+ linux_nat_async_events (1);
- gdb_assert (pid == GET_PID (inferior_ptid)
- && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP);
+ return 0;
+}
+
+static void
+linux_nat_create_inferior (char *exec_file, char *allargs, char **env,
+ int from_tty)
+{
+ int saved_async = 0;
+
+ /* The fork_child mechanism is synchronous and calls target_wait, so
+ we have to mask the async mode. */
+
+ if (target_can_async_p ())
+ saved_async = linux_nat_async_mask (0);
+ else
+ {
+ /* Restore the original signal mask. */
+ sigprocmask (SIG_SETMASK, &normal_mask, NULL);
+ /* Make sure we don't block SIGCHLD during a sigsuspend. */
+ suspend_mask = normal_mask;
+ sigdelset (&suspend_mask, SIGCHLD);
+ }
+
+ linux_ops->to_create_inferior (exec_file, allargs, env, from_tty);
+
+ if (saved_async)
+ linux_nat_async_mask (saved_async);
+}
+static void
+linux_nat_attach (char *args, int from_tty)
+{
+ struct lwp_info *lp;
+ int status;
+
+ /* FIXME: We should probably accept a list of process id's, and
+ attach all of them. */
+ linux_ops->to_attach (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);
+ }
+
+ /* 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);
+
+ 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);
+ /* If this process is not using thread_db, then we still don't
+ detect any other threads, but add at least this one. */
+ add_thread_silent (lp->ptid);
+
+ /* Save the wait status to report later. */
lp->resumed = 1;
if (debug_linux_nat)
+ 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 (GET_LWP (lp->ptid) == GET_LWP (last_ptid))
+ {
+ if (stop_signal != TARGET_SIGNAL_0
+ && signal_pass_state (stop_signal))
+ *status = W_STOPCODE (target_signal_to_host (stop_signal));
+ }
+ else if (target_can_async_p ())
+ queued_waitpid (GET_LWP (lp->ptid), status, __WALL);
+ else
+ *status = lp->status;
+
+ return 0;
+}
+
static int
detach_callback (struct lwp_info *lp, void *data)
{
@@ -935,40 +1331,30 @@ 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));
@@ -987,22 +1373,44 @@ detach_callback (struct lwp_info *lp, void *data)
static void
linux_nat_detach (char *args, int from_tty)
{
+ int pid;
+ int status;
+ enum target_signal sig;
+
+ if (target_can_async_p ())
+ linux_nat_async (NULL, 0);
+
iterate_over_lwps (detach_callback, NULL);
/* Only the initial process should be left right now. */
gdb_assert (num_lwps == 1);
+ /* 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));
+ }
+
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);
+ pid = GET_PID (inferior_ptid);
+ inferior_ptid = pid_to_ptid (pid);
+ linux_ops->to_detach (args, from_tty);
- inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid));
- deprecated_child_ops.to_detach (args, from_tty);
+ if (target_can_async_p ())
+ drain_queued_events (pid);
}
/* Resume LP. */
@@ -1012,15 +1420,15 @@ resume_callback (struct lwp_info *lp, void *data)
{
if (lp->stopped && lp->status == 0)
{
- struct thread_info *tp;
-
- child_resume (pid_to_ptid (GET_LWP (lp->ptid)), 0, TARGET_SIGNAL_0);
+ linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ 0, TARGET_SIGNAL_0);
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"RC: PTRACE_CONT %s, 0, 0 (resume sibling)\n",
target_pid_to_str (lp->ptid));
lp->stopped = 0;
lp->step = 0;
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
}
return 0;
@@ -1046,6 +1454,20 @@ linux_nat_resume (ptid_t ptid, int step, enum target_signal signo)
struct lwp_info *lp;
int resume_all;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
+ step ? "step" : "resume",
+ target_pid_to_str (ptid),
+ signo ? strsignal (signo) : "0",
+ target_pid_to_str (inferior_ptid));
+
+ prune_lwps ();
+
+ if (target_can_async_p ())
+ /* Block events while we're here. */
+ linux_nat_async_events (0);
+
/* A specific PTID means `step only this process id'. */
resume_all = (PIDGET (ptid) == -1);
@@ -1060,41 +1482,85 @@ linux_nat_resume (ptid_t ptid, int step, enum target_signal signo)
ptid = inferior_ptid;
lp = find_lwp_pid (ptid);
- if (lp)
- {
- ptid = pid_to_ptid (GET_LWP (lp->ptid));
+ gdb_assert (lp != NULL);
- /* Remember if we're stepping. */
- lp->step = step;
+ ptid = pid_to_ptid (GET_LWP (lp->ptid));
- /* Mark this LWP as resumed. */
- lp->resumed = 1;
+ /* Remember if we're stepping. */
+ lp->step = step;
+
+ /* Mark this LWP as resumed. */
+ lp->resumed = 1;
+
+ /* 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. */
+
+ /* In async mode, we never have pending wait status. */
+ if (target_can_async_p () && lp->status)
+ internal_error (__FILE__, __LINE__, "Pending status in async mode");
+
+ if (lp->status && WIFSTOPPED (lp->status))
+ {
+ int saved_signo = target_signal_from_host (WSTOPSIG (lp->status));
- /* If we have a pending wait status for this thread, there is no
- point in resuming the process. */
- if (lp->status)
+ if (signal_stop_state (saved_signo) == 0
+ && signal_print_state (saved_signo) == 0
+ && signal_pass_state (saved_signo) == 1)
{
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Not short circuiting for ignored "
+ "status 0x%x\n", lp->status);
+
/* FIXME: What should we do if we are supposed to continue
this thread with a signal? */
gdb_assert (signo == TARGET_SIGNAL_0);
- return;
+ signo = saved_signo;
+ lp->status = 0;
}
+ }
- /* Mark LWP as not stopped to prevent it from being continued by
- resume_callback. */
- lp->stopped = 0;
+ 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);
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Short circuiting for status 0x%x\n",
+ lp->status);
+
+ 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);
- child_resume (ptid, step, signo);
+ linux_ops->to_resume (ptid, step, signo);
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
+
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LLR: %s %s, %s (resume event thread)\n",
step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
target_pid_to_str (ptid),
signo ? strsignal (signo) : "0");
+
+ if (target_can_async_p ())
+ {
+ target_executing = 1;
+ target_async (inferior_event_handler, 0);
+ }
}
/* Issue kill to specified lwp. */
@@ -1123,39 +1589,113 @@ 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 = new_pid;
+
+ 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_IGNORE;
+ new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid)));
+ new_lp->cloned = 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 (stopping)
+ new_lp->stopped = 1;
+ else
+ {
+ new_lp->resumed = 1;
+ ptrace (PTRACE_CONT, lp->waitstatus.value.related_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;
+ }
+
+ 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
@@ -1171,10 +1711,10 @@ wait_lwp (struct lwp_info *lp)
gdb_assert (!lp->stopped);
gdb_assert (lp->status == 0);
- pid = waitpid (GET_LWP (lp->ptid), &status, 0);
+ pid = my_waitpid (GET_LWP (lp->ptid), &status, 0);
if (pid == -1 && errno == ECHILD)
{
- pid = waitpid (GET_LWP (lp->ptid), &status, __WCLONE);
+ pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE);
if (pid == -1 && errno == ECHILD)
{
/* The thread has previously exited. We need to delete it
@@ -1213,16 +1753,7 @@ wait_lwp (struct lwp_info *lp)
if (thread_dead)
{
- if (in_thread_list (lp->ptid))
- {
- /* Core GDB cannot deal with us deleting the current thread. */
- if (!ptid_equal (lp->ptid, inferior_ptid))
- delete_thread (lp->ptid);
- printf_unfiltered (_("[%s exited]\n"),
- target_pid_to_str (lp->ptid));
- }
-
- delete_lwp (lp->ptid);
+ exit_lwp (lp);
return 0;
}
@@ -1235,13 +1766,29 @@ 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
@@ -1327,6 +1874,9 @@ 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);
@@ -1341,22 +1891,44 @@ stop_wait_callback (struct lwp_info *lp, void *data)
"SWC: Candidate SIGTRAP event in %s\n",
target_pid_to_str (lp->ptid));
}
- /* Hold the SIGTRAP for handling by linux_nat_wait. */
+ /* Hold this event/waitstatus while we check to see if
+ there are any more (we still want to get that SIGSTOP). */
stop_wait_callback (lp, data);
- /* If there's another event, throw it back into the queue. */
- if (lp->status)
+
+ if (target_can_async_p ())
{
- if (debug_linux_nat)
+ /* Don't leave a pending wait status in async mode.
+ Retrigger the breakpoint. */
+ if (!cancel_breakpoint (lp))
{
- fprintf_unfiltered (gdb_stdlog,
- "SWC: kill %s, %s\n",
- target_pid_to_str (lp->ptid),
- status_to_str ((int) status));
+ /* There was no gdb breakpoint set at pc. Put
+ the event back in the queue. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "SWC: kill %s, %s\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str ((int) status));
+ kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
}
- 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
@@ -1383,12 +1955,11 @@ stop_wait_callback (struct lwp_info *lp, void *data)
/* Hold this event/waitstatus while we check to see if
there are any more (we still want to get that SIGSTOP). */
stop_wait_callback (lp, data);
- /* If the lp->status field is still empty, use it to hold
- this event. If not, then this event must be returned
- to the event queue of the LWP. */
- if (lp->status == 0)
- lp->status = status;
- else
+
+ /* If the lp->status field is still empty, use it to
+ hold this event. If not, then this event must be
+ returned to the event queue of the LWP. */
+ if (lp->status || target_can_async_p ())
{
if (debug_linux_nat)
{
@@ -1399,6 +1970,8 @@ stop_wait_callback (struct lwp_info *lp, void *data)
}
kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
}
+ else
+ lp->status = status;
return 0;
}
}
@@ -1475,7 +2048,15 @@ flush_callback (struct lwp_info *lp, void *data)
lp->status = 0;
}
- while (linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask))
+ /* While there is a pending signal we would like to flush, continue
+ the inferior and collect another signal. But if there's already
+ a saved status that we don't want to flush, we can't resume the
+ inferior - if it stopped for some other reason we wouldn't have
+ anywhere to save the new status. In that case, we must leave the
+ signal unflushed (and possibly generate an extra SIGINT stop).
+ That's much less bad than losing a signal. */
+ while (lp->status == 0
+ && linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask))
{
int ret;
@@ -1560,6 +2141,37 @@ select_event_lwp_callback (struct lwp_info *lp, void *data)
return 0;
}
+static int
+cancel_breakpoint (struct lwp_info *lp)
+{
+ /* Arrange for a breakpoint to be hit again later. We don't keep
+ the SIGTRAP status and don't forward the SIGTRAP signal to the
+ LWP. We will handle the current event, eventually we will resume
+ this LWP, and this breakpoint will trap again.
+
+ If we do not do this, then we run the risk that the user will
+ delete or disable the breakpoint, but the LWP will have already
+ tripped on it. */
+
+ if (breakpoint_inserted_here_p (read_pc_pid (lp->ptid) -
+ gdbarch_decr_pc_after_break
+ (current_gdbarch)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "CB: Push back breakpoint for %s\n",
+ target_pid_to_str (lp->ptid));
+
+ /* Back up the PC if necessary. */
+ if (gdbarch_decr_pc_after_break (current_gdbarch))
+ write_pc_pid (read_pc_pid (lp->ptid) - gdbarch_decr_pc_after_break
+ (current_gdbarch),
+ lp->ptid);
+ return 1;
+ }
+ return 0;
+}
+
static int
cancel_breakpoints_callback (struct lwp_info *lp, void *data)
{
@@ -1582,21 +2194,9 @@ 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;
}
@@ -1610,7 +2210,7 @@ select_event_lwp (struct lwp_info **orig_lp, int *status)
int random_selector;
struct lwp_info *event_lp;
- /* Record the wait status for the origional LWP. */
+ /* Record the wait status for the original LWP. */
(*orig_lp)->status = *status;
/* Give preference to any LWP that is being single-stepped. */
@@ -1662,134 +2262,239 @@ resumed_callback (struct lwp_info *lp, void *data)
return lp->resumed;
}
-#ifdef CHILD_WAIT
+/* Stop an active thread, verify it still exists, then resume it. */
+
+static int
+stop_and_resume_callback (struct lwp_info *lp, void *data)
+{
+ struct lwp_info *ptr;
+
+ if (!lp->stopped && !lp->signalled)
+ {
+ stop_callback (lp, NULL);
+ stop_wait_callback (lp, NULL);
+ /* Resume if the lwp still exists. */
+ for (ptr = lwp_list; ptr; ptr = ptr->next)
+ if (lp == ptr)
+ {
+ resume_callback (lp, NULL);
+ resume_set_callback (lp, NULL);
+ }
+ }
+ return 0;
+}
-/* We need to override child_wait to support attaching to cloned
- processes, since a normal wait (as done by the default version)
- ignores those processes. */
+/* 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;
-/* Wait for child PTID to do something. Return id of the child,
- minus_one_ptid in case of error; store status into *OURSTATUS. */
+ lp = find_lwp_pid (pid_to_ptid (lwpid));
-ptid_t
-child_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
-{
- int save_errno;
- int status;
- pid_t pid;
+ /* Check for stop events reported by a process we didn't already
+ know about - anything not already in our LWP list.
- ourstatus->kind = TARGET_WAITKIND_IGNORE;
+ 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;
+ }
- do
+ /* 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)
{
- set_sigint_trap (); /* Causes SIGINT to be passed on to the
- attached process. */
- set_sigio_trap ();
+ lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
+ if (options & __WCLONE)
+ lp->cloned = 1;
- pid = waitpid (GET_PID (ptid), &status, 0);
- if (pid == -1 && errno == ECHILD)
- /* Try again with __WCLONE to check cloned processes. */
- pid = waitpid (GET_PID (ptid), &status, __WCLONE);
+ gdb_assert (WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGSTOP);
+ lp->signalled = 1;
- if (debug_linux_nat)
+ if (!in_thread_list (inferior_ptid))
{
- fprintf_unfiltered (gdb_stdlog,
- "CW: waitpid %ld received %s\n",
- (long) pid, status_to_str (status));
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ add_thread (inferior_ptid);
}
- save_errno = errno;
+ add_thread (lp->ptid);
+ }
+
+ /* Save the trap's siginfo in case we need it later. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP)
+ save_siginfo (lp);
- /* Make sure we don't report an event for the exit of the
- original program, if we've detached from it. */
- if (pid != -1 && !WIFSTOPPED (status) && pid != GET_PID (inferior_ptid))
- {
- pid = -1;
- save_errno = EINTR;
- }
+ /* 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 for stop events reported by a process we didn't already
- know about - in this case, anything other than inferior_ptid.
-
- 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 we want to handle debugging of
- CLONE_PTRACE processes we need to do more here, i.e. switch
- to multi-threaded mode. */
- if (pid != -1 && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP
- && pid != GET_PID (inferior_ptid))
+ /* Check if the thread has exited. */
+ if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
+ {
+ /* If this is the main thread, we must stop all threads and
+ verify if they are still alive. This is because in the nptl
+ thread model, there is no signal issued for exiting LWPs
+ other than the main thread. We only get the main thread exit
+ signal once all child threads have already exited. If we
+ stop all the threads and use the stop_wait_callback to check
+ if they have exited we can determine whether this signal
+ should be ignored or whether it means the end of the debugged
+ application, regardless of which threading model is being
+ used. */
+ if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
{
- linux_record_stopped_pid (pid);
- pid = -1;
- save_errno = EINTR;
+ lp->stopped = 1;
+ iterate_over_lwps (stop_and_resume_callback, NULL);
}
- /* Handle GNU/Linux's extended waitstatus for trace events. */
- if (pid != -1 && WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP
- && status >> 16 != 0)
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
+
+ /* If there is at least one more LWP, then the exit signal was
+ not the end of the debugged application and should be
+ ignored. */
+ if (num_lwps > 0)
{
- linux_handle_extended_wait (pid, status, ourstatus);
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (running_callback, NULL));
- /* If we see a clone event, detach the child, and don't
- report the event. It would be nice to offer some way to
- switch into a non-thread-db based threaded mode at this
- point. */
- if (ourstatus->kind == TARGET_WAITKIND_SPURIOUS)
- {
- ptrace (PTRACE_DETACH, ourstatus->value.related_pid, 0, 0);
- ourstatus->kind = TARGET_WAITKIND_IGNORE;
- ptrace (PTRACE_CONT, pid, 0, 0);
- pid = -1;
- save_errno = EINTR;
- }
+ /* Discard the event. */
+ return NULL;
}
-
- clear_sigio_trap ();
- clear_sigint_trap ();
}
- while (pid == -1 && save_errno == EINTR);
- if (pid == -1)
+ /* 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))
{
- warning (_("Child process unexpectedly missing: %s"),
- safe_strerror (errno));
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
- /* Claim it exited with unknown signal. */
- ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
- ourstatus->value.sig = TARGET_SIGNAL_UNKNOWN;
- return minus_one_ptid;
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (running_callback, NULL));
+
+ /* Discard the event. */
+ return NULL;
}
- if (ourstatus->kind == TARGET_WAITKIND_IGNORE)
- store_waitstatus (ourstatus, status);
+ /* 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));
- return pid_to_ptid (pid);
-}
+ /* This is a delayed SIGSTOP. */
+ lp->signalled = 0;
-#endif
+ registers_changed ();
-/* Stop an active thread, verify it still exists, then resume it. */
+ 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));
-static int
-stop_and_resume_callback (struct lwp_info *lp, void *data)
+ 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)
{
- struct lwp_info *ptr;
+ 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);
+ }
+}
- if (!lp->stopped && !lp->signalled)
+/* 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)
{
- stop_callback (lp, NULL);
- stop_wait_callback (lp, NULL);
- /* Resume if the lwp still exists. */
- for (ptr = lwp_list; ptr; ptr = ptr->next)
- if (lp == ptr)
- {
- resume_callback (lp, NULL);
- resume_set_callback (lp, NULL);
- }
+ struct waitpid_result *next = w->next;
+ linux_nat_event_pipe_push (w->pid,
+ w->status,
+ w->options);
+ xfree (w);
+ w = next;
}
- return 0;
+ 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
@@ -1801,20 +2506,34 @@ linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
pid_t pid = PIDGET (ptid);
sigset_t flush_mask;
- sigemptyset (&flush_mask);
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "LLW: enter\n");
- /* Make sure SIGCHLD is blocked. */
- if (!sigismember (&blocked_mask, SIGCHLD))
+ /* The first time we get here after starting a new inferior, we may
+ not have added it to the LWP list yet - this is the earliest
+ moment at which we know its PID. */
+ if (num_lwps == 0)
{
- sigaddset (&blocked_mask, SIGCHLD);
- sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
+ gdb_assert (!is_lwp (inferior_ptid));
+
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ lp = add_lwp (inferior_ptid);
+ lp->resumed = 1;
+ /* Add the main thread to GDB's thread list. */
+ add_thread_silent (lp->ptid);
}
+ sigemptyset (&flush_mask);
+
+ if (target_can_async_p ())
+ /* Block events while we're here. */
+ target_async (NULL, 0);
+
retry:
- /* Make sure there is at least one LWP that has been resumed, at
- least if there are any LWPs at all. */
- gdb_assert (num_lwps == 0 || iterate_over_lwps (resumed_callback, NULL));
+ /* Make sure there is at least one LWP that has been resumed. */
+ gdb_assert (iterate_over_lwps (resumed_callback, NULL));
/* First check if there is a LWP with a wait status pending. */
if (pid == -1)
@@ -1823,6 +2542,10 @@ 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;
@@ -1833,7 +2556,7 @@ 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;
@@ -1878,8 +2601,8 @@ retry:
/* Resume the thread. It should halt immediately returning the
pending SIGSTOP. */
registers_changed ();
- child_resume (pid_to_ptid (GET_LWP (lp->ptid)), lp->step,
- TARGET_SIGNAL_0);
+ 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 (expect SIGSTOP)\n",
@@ -1892,15 +2615,24 @@ retry:
stop_wait_callback (lp, NULL);
}
- set_sigint_trap (); /* Causes SIGINT to be passed on to the
- attached process. */
- set_sigio_trap ();
+ if (!target_can_async_p ())
+ {
+ /* Causes SIGINT to be passed on to the attached process. */
+ set_sigint_trap ();
+ set_sigio_trap ();
+ }
while (status == 0)
{
pid_t lwpid;
- lwpid = 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);
@@ -1912,187 +2644,10 @@ retry:
(long) lwpid, status_to_str (status));
}
- lp = find_lwp_pid (pid_to_ptid (lwpid));
-
- /* Check for stop events reported by a process we didn't
- already know about - anything not already in our LWP
- list.
-
- If we're expecting to receive stopped processes after
- fork, vfork, and clone events, then we'll just add the
- new one to our list and go back to waiting for the event
- to be reported - the stopped process might be returned
- from waitpid before or after the event is. */
- if (WIFSTOPPED (status) && !lp)
- {
- linux_record_stopped_pid (lwpid);
- status = 0;
- continue;
- }
-
- /* Make sure we don't report an event for the exit of an LWP not in
- our list, i.e. not part of the current process. This can happen
- if we detach from a program we original forked and then it
- exits. */
- if (!WIFSTOPPED (status) && !lp)
- {
- status = 0;
- continue;
- }
-
- /* NOTE drow/2003-06-17: This code seems to be meant for debugging
- CLONE_PTRACE processes which do not use the thread library -
- otherwise we wouldn't find the new LWP this way. That doesn't
- currently work, and the following code is currently unreachable
- due to the two blocks above. If it's fixed some day, this code
- should be broken out into a function so that we can also pick up
- LWPs from the new interface. */
+ lp = linux_nat_filter_event (lwpid, status, options);
if (!lp)
{
- lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
- if (options & __WCLONE)
- lp->cloned = 1;
-
- if (threaded)
- {
- gdb_assert (WIFSTOPPED (status)
- && WSTOPSIG (status) == SIGSTOP);
- lp->signalled = 1;
-
- if (!in_thread_list (inferior_ptid))
- {
- inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
- GET_PID (inferior_ptid));
- add_thread (inferior_ptid);
- }
-
- add_thread (lp->ptid);
- printf_unfiltered (_("[New %s]\n"),
- target_pid_to_str (lp->ptid));
- }
- }
-
- /* Handle GNU/Linux's extended waitstatus for trace events. */
- if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: Handling extended status 0x%06x\n",
- status);
- if (linux_nat_handle_extended (lp, status))
- {
- status = 0;
- continue;
- }
- }
-
- /* Check if the thread has exited. */
- if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
- {
- if (in_thread_list (lp->ptid))
- {
- /* Core GDB cannot deal with us deleting the current
- thread. */
- if (!ptid_equal (lp->ptid, inferior_ptid))
- delete_thread (lp->ptid);
- printf_unfiltered (_("[%s exited]\n"),
- target_pid_to_str (lp->ptid));
- }
-
- /* If this is the main thread, we must stop all threads and
- verify if they are still alive. This is because in the nptl
- thread model, there is no signal issued for exiting LWPs
- other than the main thread. We only get the main thread
- exit signal once all child threads have already exited.
- If we stop all the threads and use the stop_wait_callback
- to check if they have exited we can determine whether this
- signal should be ignored or whether it means the end of the
- debugged application, regardless of which threading model
- is being used. */
- if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
- {
- lp->stopped = 1;
- iterate_over_lwps (stop_and_resume_callback, NULL);
- }
-
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s exited.\n",
- target_pid_to_str (lp->ptid));
-
- delete_lwp (lp->ptid);
-
- /* If there is at least one more LWP, then the exit signal
- was not the end of the debugged application and should be
- ignored. */
- if (num_lwps > 0)
- {
- /* Make sure there is at least one thread running. */
- gdb_assert (iterate_over_lwps (running_callback, NULL));
-
- /* Discard the event. */
- status = 0;
- continue;
- }
- }
-
- /* Check if the current LWP has previously exited. In the nptl
- thread model, LWPs other than the main thread do not issue
- signals when they exit so we must check whenever the thread
- has stopped. A similar check is made in stop_wait_callback(). */
- if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid))
- {
- if (in_thread_list (lp->ptid))
- {
- /* Core GDB cannot deal with us deleting the current
- thread. */
- if (!ptid_equal (lp->ptid, inferior_ptid))
- delete_thread (lp->ptid);
- printf_unfiltered (_("[%s exited]\n"),
- target_pid_to_str (lp->ptid));
- }
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s exited.\n",
- target_pid_to_str (lp->ptid));
-
- delete_lwp (lp->ptid);
-
- /* Make sure there is at least one thread running. */
- gdb_assert (iterate_over_lwps (running_callback, NULL));
-
- /* Discard the event. */
- status = 0;
- continue;
- }
-
- /* Make sure we don't report a SIGSTOP that we sent
- ourselves in an attempt to stop an LWP. */
- if (lp->signalled
- && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP)
- {
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: Delayed SIGSTOP caught for %s.\n",
- target_pid_to_str (lp->ptid));
-
- /* This is a delayed SIGSTOP. */
- lp->signalled = 0;
-
- registers_changed ();
- child_resume (pid_to_ptid (GET_LWP (lp->ptid)), lp->step,
- TARGET_SIGNAL_0);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
- lp->step ?
- "PTRACE_SINGLESTEP" : "PTRACE_CONT",
- target_pid_to_str (lp->ptid));
-
- lp->stopped = 0;
- gdb_assert (lp->resumed);
-
- /* Discard the event. */
+ /* A discarded event. */
status = 0;
continue;
}
@@ -2105,17 +2660,38 @@ retry:
/* Alternate between checking cloned and uncloned processes. */
options ^= __WCLONE;
- /* And suspend every time we have checked both. */
+ /* And every time we have checked both:
+ In async mode, return to event loop;
+ In sync mode, suspend waiting for a SIGCHLD signal. */
if (options & __WCLONE)
- sigsuspend (&suspend_mask);
+ {
+ if (target_can_async_p ())
+ {
+ /* No interesting event. */
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
+ /* Get ready for the next event. */
+ target_async (inferior_event_handler, 0);
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
+
+ return minus_one_ptid;
+ }
+
+ sigsuspend (&suspend_mask);
+ }
}
/* We shouldn't end up here unless we want to try again. */
gdb_assert (status == 0);
}
- clear_sigio_trap ();
- clear_sigint_trap ();
+ if (!target_can_async_p ())
+ {
+ clear_sigio_trap ();
+ clear_sigint_trap ();
+ }
gdb_assert (lp);
@@ -2130,7 +2706,10 @@ retry:
{
int signo = target_signal_from_host (WSTOPSIG (status));
- if (signal_stop_state (signo) == 0
+ /* If we get a signal while single-stepping, we may need special
+ care, e.g. to skip the signal handler. Defer to common code. */
+ if (!lp->step
+ && signal_stop_state (signo) == 0
&& signal_print_state (signo) == 0
&& signal_pass_state (signo) == 1)
{
@@ -2140,7 +2719,8 @@ retry:
newly attached threads may cause an unwanted delay in
getting them running. */
registers_changed ();
- child_resume (pid_to_ptid (GET_LWP (lp->ptid)), lp->step, signo);
+ linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, signo);
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LLW: %s %s, %s (preempt 'handle')\n",
@@ -2189,12 +2769,9 @@ retry:
the comment in cancel_breakpoints_callback to find out why. */
iterate_over_lwps (cancel_breakpoints_callback, lp);
- /* If we're not running in "threaded" mode, we'll report the bare
- process id. */
-
if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP)
{
- trap_ptid = (threaded ? lp->ptid : pid_to_ptid (GET_LWP (lp->ptid)));
+ trap_ptid = lp->ptid;
if (debug_linux_nat)
fprintf_unfiltered (gdb_stdlog,
"LLW: trap_ptid is %s.\n",
@@ -2211,7 +2788,14 @@ retry:
else
store_waitstatus (ourstatus, status);
- return (threaded ? lp->ptid : pid_to_ptid (GET_LWP (lp->ptid)));
+ /* 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;
}
static int
@@ -2244,12 +2828,19 @@ kill_wait_callback (struct lwp_info *lp, void *data)
{
do
{
- pid = waitpid (GET_LWP (lp->ptid), NULL, __WCLONE);
- if (pid != (pid_t) -1 && debug_linux_nat)
+ pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE);
+ 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));
@@ -2259,12 +2850,15 @@ kill_wait_callback (struct lwp_info *lp, void *data)
do
{
- pid = waitpid (GET_LWP (lp->ptid), NULL, 0);
- if (pid != (pid_t) -1 && debug_linux_nat)
+ pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0);
+ 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));
@@ -2276,20 +2870,41 @@ kill_wait_callback (struct lwp_info *lp, void *data)
static void
linux_nat_kill (void)
{
- /* Kill all LWP's ... */
- iterate_over_lwps (kill_callback, NULL);
+ struct target_waitstatus last;
+ ptid_t last_ptid;
+ int status;
- /* ... and wait until we've flushed all events. */
- iterate_over_lwps (kill_wait_callback, NULL);
+ if (target_can_async_p ())
+ target_async (NULL, 0);
- target_mourn_inferior ();
-}
+ /* 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. */
-static void
-linux_nat_create_inferior (char *exec_file, char *allargs, char **env,
- int from_tty)
-{
- deprecated_child_ops.to_create_inferior (exec_file, allargs, env, from_tty);
+ get_last_target_status (&last_ptid, &last);
+
+ if (last.kind == TARGET_WAITKIND_FORKED
+ || last.kind == TARGET_WAITKIND_VFORKED)
+ {
+ ptrace (PT_KILL, last.value.related_pid, 0, 0);
+ wait (&status);
+ }
+
+ if (forks_exist_p ())
+ {
+ linux_fork_killall ();
+ drain_queued_events (-1);
+ }
+ else
+ {
+ /* Kill all LWP's ... */
+ iterate_over_lwps (kill_callback, NULL);
+
+ /* ... and wait until we've flushed all events. */
+ iterate_over_lwps (kill_wait_callback, NULL);
+ }
+
+ target_mourn_inferior ();
}
static void
@@ -2300,26 +2915,34 @@ linux_nat_mourn_inferior (void)
/* Destroy LWP info; it's no longer valid. */
init_lwp_list ();
- /* Restore the original signal mask. */
- sigprocmask (SIG_SETMASK, &normal_mask, NULL);
- sigemptyset (&blocked_mask);
-
- deprecated_child_ops.to_mourn_inferior ();
+ if (! forks_exist_p ())
+ {
+ /* Normal case, no other forks available. */
+ if (target_can_async_p ())
+ linux_nat_async (NULL, 0);
+ linux_ops->to_mourn_inferior ();
+ }
+ else
+ /* Multi-fork case. The current inferior_ptid has exited, but
+ there are other viable forks to debug. Delete the exiting
+ one and context-switch to the first available. */
+ linux_fork_mourn_inferior ();
}
-static int
-linux_nat_xfer_memory (CORE_ADDR memaddr, char *myaddr, int len, int write,
- struct mem_attrib *attrib, struct target_ops *target)
+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 ();
- int xfer;
+ LONGEST xfer;
if (is_lwp (inferior_ptid))
inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid));
- xfer = linux_proc_xfer_memory (memaddr, myaddr, len, write, attrib, target);
- if (xfer == 0)
- xfer = child_xfer_memory (memaddr, myaddr, len, write, attrib, target);
+ xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf,
+ offset, len);
do_cleanups (old_chain);
return xfer;
@@ -2337,7 +2960,13 @@ linux_nat_thread_alive (ptid_t ptid)
"LLTA: PTRACE_PEEKUSER %s, 0, 0 (%s)\n",
target_pid_to_str (ptid),
errno ? safe_strerror (errno) : "OK");
- if (errno)
+
+ /* Not every Linux kernel implements PTRACE_PEEKUSER. But we can
+ handle that case gracefully since ptrace will first do a lookup
+ for the process based upon the passed-in pid. If that fails we
+ will get either -ESRCH or -EPERM, otherwise the child exists and
+ is alive. */
+ if (errno == ESRCH || errno == EPERM)
return 0;
return 1;
@@ -2348,7 +2977,9 @@ linux_nat_pid_to_str (ptid_t ptid)
{
static char buf[64];
- if (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;
@@ -2357,43 +2988,16 @@ linux_nat_pid_to_str (ptid_t ptid)
return normal_pid_to_str (ptid);
}
-static void
-init_linux_nat_ops (void)
-{
-#if 0
- linux_nat_ops.to_open = linux_nat_open;
-#endif
- linux_nat_ops.to_shortname = "lwp-layer";
- linux_nat_ops.to_longname = "lwp-layer";
- linux_nat_ops.to_doc = "Low level threads support (LWP layer)";
- linux_nat_ops.to_attach = linux_nat_attach;
- linux_nat_ops.to_detach = linux_nat_detach;
- linux_nat_ops.to_resume = linux_nat_resume;
- linux_nat_ops.to_wait = linux_nat_wait;
- /* fetch_inferior_registers and store_inferior_registers will
- honor the LWP id, so we can use them directly. */
- linux_nat_ops.to_fetch_registers = fetch_inferior_registers;
- linux_nat_ops.to_store_registers = store_inferior_registers;
- linux_nat_ops.deprecated_xfer_memory = linux_nat_xfer_memory;
- linux_nat_ops.to_kill = linux_nat_kill;
- linux_nat_ops.to_create_inferior = linux_nat_create_inferior;
- linux_nat_ops.to_mourn_inferior = linux_nat_mourn_inferior;
- linux_nat_ops.to_thread_alive = linux_nat_thread_alive;
- linux_nat_ops.to_pid_to_str = linux_nat_pid_to_str;
- linux_nat_ops.to_post_startup_inferior = child_post_startup_inferior;
- linux_nat_ops.to_post_attach = child_post_attach;
- linux_nat_ops.to_insert_fork_catchpoint = child_insert_fork_catchpoint;
- linux_nat_ops.to_insert_vfork_catchpoint = child_insert_vfork_catchpoint;
- linux_nat_ops.to_insert_exec_catchpoint = child_insert_exec_catchpoint;
-
- linux_nat_ops.to_stratum = thread_stratum;
- linux_nat_ops.to_has_thread_control = tc_schedlock;
- linux_nat_ops.to_magic = OPS_MAGIC;
-}
-
static void
sigchld_handler (int signo)
{
+ if (linux_nat_async_enabled
+ && linux_nat_async_events_enabled
+ && signo == SIGCHLD)
+ /* It is *always* a bug to hit this. */
+ internal_error (__FILE__, __LINE__,
+ "sigchld_handler called when async events are enabled");
+
/* Do nothing. The only reason for this handler is that it allows
us to use sigsuspend in linux_nat_wait above to wait for the
arrival of a SIGCHLD. */
@@ -2402,8 +3006,8 @@ 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;
@@ -2433,7 +3037,8 @@ read_mapping (FILE *mapfile,
int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx",
addr, endaddr, permissions, offset, device, inode);
- if (ret > 0 && ret != EOF && *inode != 0)
+ filename[0] = '\0';
+ if (ret > 0 && ret != EOF)
{
/* Eat everything up to EOL for the filename. This will prevent
weird filenames (such as one with embedded whitespace) from
@@ -2444,11 +3049,7 @@ read_mapping (FILE *mapfile,
only. */
ret += fscanf (mapfile, "%[^\n]\n", filename);
}
- else
- {
- filename[0] = '\0'; /* no filename */
- fscanf (mapfile, "\n");
- }
+
return (ret != 0 && ret != EOF);
}
@@ -2495,7 +3096,7 @@ 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");
}
@@ -2521,21 +3122,57 @@ linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid,
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;
+
+ 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);
+ 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);
+ 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));
+
#ifdef FILL_FPXREGSET
- fill_fpxregset (&fpxregs, -1);
+ if (core_regset_p
+ && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg-xfp",
+ sizeof (fpxregs))) != NULL
+ && regset->collect_regset != NULL)
+ regset->collect_regset (regset, regcache, -1,
+ &fpxregs, sizeof (fpxregs));
+ else
+ fill_fpxregset (regcache, &fpxregs, -1);
+
note_data = (char *) elfcore_write_prxfpreg (obfd,
note_data,
note_size,
@@ -2559,21 +3196,13 @@ 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->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;
}
@@ -2583,15 +3212,11 @@ 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;
}
/* Fills the "to_make_corefile_note" target vector. Builds the note
@@ -2602,11 +3227,13 @@ 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;
- char *auxv;
+ gdb_byte *auxv;
int auxv_len;
if (get_exec_file (0))
@@ -2615,9 +3242,18 @@ 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,
@@ -2642,7 +3278,8 @@ linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
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,
@@ -2733,7 +3370,7 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
if (cmdline_f || all)
{
sprintf (fname1, "/proc/%lld/cmdline", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ if ((procfile = fopen (fname1, "r")) != NULL)
{
fgets (buffer, sizeof (buffer), procfile);
printf_filtered ("cmdline = '%s'\n", buffer);
@@ -2763,13 +3400,13 @@ 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)
+ if ((procfile = fopen (fname1, "r")) != NULL)
{
long long addr, endaddr, size, offset, inode;
char permissions[8], device[8], filename[MAXPATHLEN];
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",
@@ -2795,7 +3432,7 @@ 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 */
@@ -2823,7 +3460,7 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
if (status_f || all)
{
sprintf (fname1, "/proc/%lld/status", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ if ((procfile = fopen (fname1, "r")) != NULL)
{
while (fgets (buffer, sizeof (buffer), procfile) != NULL)
puts_filtered (buffer);
@@ -2835,14 +3472,15 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
if (stat_f || all)
{
sprintf (fname1, "/proc/%lld/stat", pid);
- if ((procfile = fopen (fname1, "r")) > 0)
+ if ((procfile = fopen (fname1, "r")) != NULL)
{
int itmp;
char ctmp;
+ long ltmp;
if (fscanf (procfile, "%d ", &itmp) > 0)
printf_filtered (_("Process: %d\n"), itmp);
- if (fscanf (procfile, "%s ", &buffer[0]) > 0)
+ if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0)
printf_filtered (_("Exec file: %s\n"), buffer);
if (fscanf (procfile, "%c ", &ctmp) > 0)
printf_filtered (_("State: %c\n"), ctmp);
@@ -2856,71 +3494,71 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
printf_filtered (_("TTY: %d\n"), itmp);
if (fscanf (procfile, "%d ", &itmp) > 0)
printf_filtered (_("TTY owner process group: %d\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Flags: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Minor faults (no memory page): %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Minor faults, children: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Major faults (memory page faults): %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Major faults, children: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("utime: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("stime: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("utime, children: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("stime, children: %d\n", itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("jiffies remaining in current time slice: %d\n"),
- itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered ("'nice' value: %d\n", itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("jiffies until next timeout: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered ("jiffies until next SIGALRM: %u\n",
- (unsigned int) itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("start time (jiffies since system boot): %d\n"),
- itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Virtual memory size: %u\n"),
- (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Resident set size: %u\n"), (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered ("rlim: %u\n", (unsigned int) itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Start of text: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("End of text: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0)
- printf_filtered (_("Start of stack: 0x%x\n"), itmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Flags: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Minor faults (no memory page): %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Minor faults, children: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Major faults (memory page faults): %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Major faults, children: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("utime: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("stime: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("utime, children: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("stime, children: %ld\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("jiffies remaining in current time slice: %ld\n"),
+ ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("'nice' value: %ld\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("jiffies until next timeout: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("jiffies until next SIGALRM: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("start time (jiffies since system boot): %ld\n"),
+ ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Virtual memory size: %lu\n"),
+ (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Resident set size: %lu\n"), (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("rlim: %lu\n"), (unsigned long) ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Start of text: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("End of text: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0)
+ printf_filtered (_("Start of stack: 0x%lx\n"), ltmp);
#if 0 /* Don't know how architecture-dependent the rest is...
Anyway the signal bitmap info is available from "status". */
- if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
- printf_filtered (_("Kernel stack pointer: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
- printf_filtered (_("Kernel instr pointer: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Pending signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Blocked signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Ignored signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%d ", &itmp) > 0)
- printf_filtered (_("Catched signals bitmap: 0x%x\n"), itmp);
- if (fscanf (procfile, "%u ", &itmp) > 0) /* FIXME arch? */
- printf_filtered (_("wchan (system call): 0x%x\n"), itmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
+ printf_filtered (_("Kernel stack pointer: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
+ printf_filtered (_("Kernel instr pointer: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Pending signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Blocked signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Ignored signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%ld ", <mp) > 0)
+ printf_filtered (_("Catched signals bitmap: 0x%lx\n"), ltmp);
+ if (fscanf (procfile, "%lu ", <mp) > 0) /* FIXME arch? */
+ printf_filtered (_("wchan (system call): 0x%lx\n"), ltmp);
#endif
fclose (procfile);
}
@@ -2929,14 +3567,22 @@ linux_nat_info_proc_cmd (char *args, int from_tty)
}
}
-int
-linux_proc_xfer_memory (CORE_ADDR addr, char *myaddr, int len, int write,
- struct mem_attrib *attrib, struct target_ops *target)
+/* Implement the to_xfer_partial interface for memory reads using the /proc
+ filesystem. Because we can use a single read() call for /proc, this
+ can be much more efficient than banging away at PTRACE_PEEKTEXT,
+ but it doesn't support writes. */
+
+static LONGEST
+linux_proc_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, LONGEST len)
{
- int fd, ret;
+ LONGEST ret;
+ int fd;
char filename[64];
- if (write)
+ if (object != TARGET_OBJECT_MEMORY || !readbuf)
return 0;
/* Don't bother for one word. */
@@ -2955,9 +3601,9 @@ linux_proc_xfer_memory (CORE_ADDR addr, char *myaddr, int len, int write,
32-bit platforms (for instance, SPARC debugging a SPARC64
application). */
#ifdef HAVE_PREAD64
- if (pread64 (fd, myaddr, len, addr) != len)
+ if (pread64 (fd, readbuf, len, offset) != len)
#else
- if (lseek (fd, addr, SEEK_SET) == -1 || read (fd, myaddr, len) != len)
+ if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len)
#endif
ret = 0;
else
@@ -3048,14 +3694,506 @@ linux_proc_pending_signals (int pid, sigset_t *pending, sigset_t *blocked, sigse
fclose (procfile);
}
+static LONGEST
+linux_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
+{
+ LONGEST xfer;
+
+ if (object == TARGET_OBJECT_AUXV)
+ return procfs_xfer_auxv (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
+ xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf,
+ offset, len);
+ if (xfer != 0)
+ return xfer;
+
+ return super_xfer_partial (ops, object, annex, readbuf, writebuf,
+ offset, len);
+}
+
+/* Create a prototype generic GNU/Linux target. The client can override
+ it with local methods. */
+
+static void
+linux_target_install_ops (struct target_ops *t)
+{
+ 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;
+
+ super_xfer_partial = t->to_xfer_partial;
+ t->to_xfer_partial = linux_xfer_partial;
+}
+
+struct target_ops *
+linux_target (void)
+{
+ struct target_ops *t;
+
+ t = inf_ptrace_target ();
+ linux_target_install_ops (t);
+
+ 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;
+}
+
+/* Controls if async mode is permitted. */
+static int linux_async_permitted = 0;
+
+/* The set command writes to this variable. If the inferior is
+ executing, linux_nat_async_permitted is *not* updated. */
+static int linux_async_permitted_1 = 0;
+
+static void
+set_maintenance_linux_async_permitted (char *args, int from_tty,
+ struct cmd_list_element *c)
+{
+ if (target_has_execution)
+ {
+ linux_async_permitted_1 = linux_async_permitted;
+ error (_("Cannot change this setting while the inferior is running."));
+ }
+
+ linux_async_permitted = linux_async_permitted_1;
+ linux_nat_set_async_mode (linux_async_permitted);
+}
+
+static void
+show_maintenance_linux_async_permitted (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+ fprintf_filtered (file, _("\
+Controlling the GNU/Linux inferior in asynchronous mode is %s.\n"),
+ value);
+}
+
+/* target_is_async_p implementation. */
+
+static int
+linux_nat_is_async_p (void)
+{
+ /* NOTE: palves 2008-03-21: We're only async when the user requests
+ it explicitly with the "maintenance set linux-async" command.
+ Someday, linux will always be async. */
+ if (!linux_async_permitted)
+ return 0;
+
+ return 1;
+}
+
+/* target_can_async_p implementation. */
+
+static int
+linux_nat_can_async_p (void)
+{
+ /* NOTE: palves 2008-03-21: We're only async when the user requests
+ it explicitly with the "maintenance set linux-async" command.
+ Someday, linux will always be async. */
+ if (!linux_async_permitted)
+ return 0;
+
+ /* See target.h/target_async_mask. */
+ return linux_nat_async_mask_value;
+}
+
+/* target_async_mask implementation. */
+
+static int
+linux_nat_async_mask (int mask)
+{
+ int current_state;
+ current_state = linux_nat_async_mask_value;
+
+ if (current_state != mask)
+ {
+ if (mask == 0)
+ {
+ linux_nat_async (NULL, 0);
+ linux_nat_async_mask_value = mask;
+ /* We're in sync mode. Make sure SIGCHLD isn't handled by
+ async_sigchld_handler when we come out of sigsuspend in
+ linux_nat_wait. */
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
+ }
+ else
+ {
+ /* Restore the async handler. */
+ sigaction (SIGCHLD, &async_sigchld_action, NULL);
+ linux_nat_async_mask_value = mask;
+ linux_nat_async (inferior_event_handler, 0);
+ }
+ }
+
+ return current_state;
+}
+
+/* Pop an event from the event pipe. */
+
+static int
+linux_nat_event_pipe_pop (int* ptr_status, int* ptr_options)
+{
+ struct waitpid_result event = {0};
+ int ret;
+
+ do
+ {
+ ret = read (linux_nat_event_pipe[0], &event, sizeof (event));
+ }
+ while (ret == -1 && errno == EINTR);
+
+ gdb_assert (ret == sizeof (event));
+
+ *ptr_status = event.status;
+ *ptr_options = event.options;
+
+ linux_nat_num_queued_events--;
+
+ return event.pid;
+}
+
+/* Push an event into the event pipe. */
+
+static void
+linux_nat_event_pipe_push (int pid, int status, int options)
+{
+ int ret;
+ struct waitpid_result event = {0};
+ event.pid = pid;
+ event.status = status;
+ event.options = options;
+
+ do
+ {
+ ret = write (linux_nat_event_pipe[1], &event, sizeof (event));
+ gdb_assert ((ret == -1 && errno == EINTR) || ret == sizeof (event));
+ } while (ret == -1 && errno == EINTR);
+
+ linux_nat_num_queued_events++;
+}
+
+static void
+get_pending_events (void)
+{
+ int status, options, pid;
+
+ if (!linux_nat_async_enabled || !linux_nat_async_events_enabled)
+ internal_error (__FILE__, __LINE__,
+ "get_pending_events called with async masked");
+
+ while (1)
+ {
+ status = 0;
+ options = __WCLONE | WNOHANG;
+
+ do
+ {
+ pid = waitpid (-1, &status, options);
+ }
+ while (pid == -1 && errno == EINTR);
+
+ if (pid <= 0)
+ {
+ options = WNOHANG;
+ do
+ {
+ pid = waitpid (-1, &status, options);
+ }
+ while (pid == -1 && errno == EINTR);
+ }
+
+ if (pid <= 0)
+ /* No more children reporting events. */
+ break;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "\
+get_pending_events: pid(%d), status(%x), options (%x)\n",
+ pid, status, options);
+
+ linux_nat_event_pipe_push (pid, status, options);
+ }
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "\
+get_pending_events: linux_nat_num_queued_events(%d)\n",
+ linux_nat_num_queued_events);
+}
+
+/* SIGCHLD handler for async mode. */
+
+static void
+async_sigchld_handler (int signo)
+{
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog, "async_sigchld_handler\n");
+
+ get_pending_events ();
+}
+
+/* Enable or disable async SIGCHLD handling. */
+
+static int
+linux_nat_async_events (int enable)
+{
+ int current_state = linux_nat_async_events_enabled;
+
+ if (debug_linux_nat_async)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNAE: enable(%d): linux_nat_async_events_enabled(%d), "
+ "linux_nat_num_queued_events(%d)\n",
+ enable, linux_nat_async_events_enabled,
+ linux_nat_num_queued_events);
+
+ if (current_state != enable)
+ {
+ sigset_t mask;
+ sigemptyset (&mask);
+ sigaddset (&mask, SIGCHLD);
+ if (enable)
+ {
+ /* Unblock target events. */
+ linux_nat_async_events_enabled = 1;
+
+ local_event_queue_to_pipe ();
+ /* While in masked async, we may have not collected all the
+ pending events. Get them out now. */
+ get_pending_events ();
+ sigprocmask (SIG_UNBLOCK, &mask, NULL);
+ }
+ else
+ {
+ /* Block target events. */
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+ linux_nat_async_events_enabled = 0;
+ /* Get events out of queue, and make them available to
+ queued_waitpid / my_waitpid. */
+ pipe_to_local_event_queue ();
+ }
+ }
+
+ return current_state;
+}
+
+static int async_terminal_is_ours = 1;
+
+/* target_terminal_inferior implementation. */
+
+static void
+linux_nat_terminal_inferior (void)
+{
+ if (!target_is_async_p ())
+ {
+ /* Async mode is disabled. */
+ terminal_inferior ();
+ return;
+ }
+
+ /* GDB should never give the terminal to the inferior, if the
+ inferior is running in the background (run&, continue&, etc.).
+ This check can be removed when the common code is fixed. */
+ if (!sync_execution)
+ return;
+
+ terminal_inferior ();
+
+ if (!async_terminal_is_ours)
+ return;
+
+ delete_file_handler (input_fd);
+ async_terminal_is_ours = 0;
+ set_sigint_trap ();
+}
+
+/* target_terminal_ours implementation. */
+
void
-_initialize_linux_nat (void)
+linux_nat_terminal_ours (void)
{
- struct sigaction action;
- extern void thread_db_init (struct target_ops *);
+ if (!target_is_async_p ())
+ {
+ /* Async mode is disabled. */
+ terminal_ours ();
+ return;
+ }
+
+ /* GDB should never give the terminal to the inferior if the
+ inferior is running in the background (run&, continue&, etc.),
+ but claiming it sure should. */
+ terminal_ours ();
+
+ if (!sync_execution)
+ return;
+
+ if (async_terminal_is_ours)
+ return;
+
+ clear_sigint_trap ();
+ add_file_handler (input_fd, stdin_event_handler, 0);
+ async_terminal_is_ours = 1;
+}
+
+static void (*async_client_callback) (enum inferior_event_type event_type,
+ void *context);
+static void *async_client_context;
+
+static void
+linux_nat_async_file_handler (int error, gdb_client_data client_data)
+{
+ async_client_callback (INF_REG_EVENT, async_client_context);
+}
+
+/* target_async implementation. */
+
+static void
+linux_nat_async (void (*callback) (enum inferior_event_type event_type,
+ void *context), void *context)
+{
+ if (linux_nat_async_mask_value == 0 || !linux_nat_async_enabled)
+ internal_error (__FILE__, __LINE__,
+ "Calling target_async when async is masked");
+
+ if (callback != NULL)
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+ add_file_handler (linux_nat_event_pipe[0],
+ linux_nat_async_file_handler, NULL);
+
+ linux_nat_async_events (1);
+ }
+ else
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+
+ linux_nat_async_events (0);
+ delete_file_handler (linux_nat_event_pipe[0]);
+ }
+ return;
+}
+
+/* Enable/Disable async mode. */
+
+static void
+linux_nat_set_async_mode (int on)
+{
+ if (linux_nat_async_enabled != on)
+ {
+ if (on)
+ {
+ gdb_assert (waitpid_queue == NULL);
+ sigaction (SIGCHLD, &async_sigchld_action, NULL);
+
+ if (pipe (linux_nat_event_pipe) == -1)
+ internal_error (__FILE__, __LINE__,
+ "creating event pipe failed.");
+
+ fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK);
+ fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK);
+ }
+ else
+ {
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
+
+ drain_queued_events (-1);
+
+ linux_nat_num_queued_events = 0;
+ close (linux_nat_event_pipe[0]);
+ close (linux_nat_event_pipe[1]);
+ linux_nat_event_pipe[0] = linux_nat_event_pipe[1] = -1;
+
+ }
+ }
+ linux_nat_async_enabled = on;
+}
+
+void
+linux_nat_add_target (struct target_ops *t)
+{
+ /* 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
+ process stratum target. */
+ linux_ops_saved = *t;
+ linux_ops = &linux_ops_saved;
+
+ /* Override some methods for multithreading. */
+ t->to_create_inferior = linux_nat_create_inferior;
+ t->to_attach = linux_nat_attach;
+ t->to_detach = linux_nat_detach;
+ t->to_resume = linux_nat_resume;
+ t->to_wait = linux_nat_wait;
+ t->to_xfer_partial = linux_nat_xfer_partial;
+ t->to_kill = linux_nat_kill;
+ t->to_mourn_inferior = linux_nat_mourn_inferior;
+ t->to_thread_alive = linux_nat_thread_alive;
+ t->to_pid_to_str = linux_nat_pid_to_str;
+ t->to_has_thread_control = tc_schedlock;
+
+ t->to_can_async_p = linux_nat_can_async_p;
+ t->to_is_async_p = linux_nat_is_async_p;
+ t->to_async = linux_nat_async;
+ t->to_async_mask = linux_nat_async_mask;
+ t->to_terminal_inferior = linux_nat_terminal_inferior;
+ t->to_terminal_ours = linux_nat_terminal_ours;
+
+ /* We don't change the stratum; this target will sit at
+ process_stratum and thread_db will set at thread_stratum. This
+ is a little strange, since this is a multi-threaded-capable
+ target, but we want to be on the stack below thread_db, and we
+ also want to be used for single-threaded processes. */
+
+ add_target (t);
+
+ /* TODO: Eliminate this and have libthread_db use
+ find_target_beneath. */
+ thread_db_init (t);
+}
+
+/* Register a method to call whenever a new thread is attached. */
+void
+linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t))
+{
+ /* Save the pointer. We only support a single registered instance
+ of the GNU/Linux native target, so we do not need to map this to
+ T. */
+ linux_nat_new_thread = new_thread;
+}
+
+/* Return the saved siginfo associated with PTID. */
+struct siginfo *
+linux_nat_get_siginfo (ptid_t ptid)
+{
+ struct lwp_info *lp = find_lwp_pid (ptid);
+
+ gdb_assert (lp != NULL);
+
+ return &lp->siginfo;
+}
- deprecated_child_ops.to_find_memory_regions = linux_nat_find_memory_regions;
- deprecated_child_ops.to_make_corefile_notes = linux_nat_make_corefile_notes;
+void
+_initialize_linux_nat (void)
+{
+ sigset_t mask;
add_info ("proc", linux_nat_info_proc_cmd, _("\
Show /proc process information about any running process.\n\
@@ -3066,31 +4204,63 @@ Specify any of the following keywords for detailed info:\n\
status -- list a different bunch of random process info.\n\
all -- list all available /proc info."));
- init_linux_nat_ops ();
- add_target (&linux_nat_ops);
- thread_db_init (&linux_nat_ops);
+ 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);
- /* Save the original signal mask. */
+ add_setshow_boolean_cmd ("linux-async", class_maintenance,
+ &linux_async_permitted_1, _("\
+Set whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\
+Show whether gdb controls the GNU/Linux inferior in asynchronous mode."), _("\
+Tells gdb whether to control the GNU/Linux inferior in asynchronous mode."),
+ set_maintenance_linux_async_permitted,
+ show_maintenance_linux_async_permitted,
+ &maintenance_set_cmdlist,
+ &maintenance_show_cmdlist);
+
+ /* Block SIGCHLD by default. Doing this early prevents it getting
+ unblocked if an exception is thrown due to an error while the
+ inferior is starting (sigsetjmp/siglongjmp). */
+ sigemptyset (&mask);
+ sigaddset (&mask, SIGCHLD);
+ sigprocmask (SIG_BLOCK, &mask, NULL);
+
+ /* Save this mask as the default. */
sigprocmask (SIG_SETMASK, NULL, &normal_mask);
- action.sa_handler = sigchld_handler;
- sigemptyset (&action.sa_mask);
- action.sa_flags = 0;
- sigaction (SIGCHLD, &action, NULL);
+ /* The synchronous SIGCHLD handler. */
+ sync_sigchld_action.sa_handler = sigchld_handler;
+ sigemptyset (&sync_sigchld_action.sa_mask);
+ sync_sigchld_action.sa_flags = SA_RESTART;
+
+ /* Make it the default. */
+ sigaction (SIGCHLD, &sync_sigchld_action, NULL);
/* Make sure we don't block SIGCHLD during a sigsuspend. */
sigprocmask (SIG_SETMASK, NULL, &suspend_mask);
sigdelset (&suspend_mask, SIGCHLD);
- sigemptyset (&blocked_mask);
+ /* SIGCHLD handler for async mode. */
+ async_sigchld_action.sa_handler = async_sigchld_handler;
+ sigemptyset (&async_sigchld_action.sa_mask);
+ async_sigchld_action.sa_flags = SA_RESTART;
- add_setshow_zinteger_cmd ("lin-lwp", no_class, &debug_linux_nat, _("\
-Set debugging of GNU/Linux lwp module."), _("\
-Show debugging of GNU/Linux lwp module."), _("\
-Enables printf debugging output."),
- NULL,
- NULL, /* FIXME: i18n: */
- &setdebuglist, &showdebuglist);
+ /* Install the default mode. */
+ linux_nat_set_async_mode (linux_async_permitted);
}
@@ -3112,7 +4282,7 @@ get_signo (const char *name)
if (ms == NULL)
return 0;
- if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (char *) &signo,
+ if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo,
sizeof (signo)) != 0)
return 0;
@@ -3126,16 +4296,24 @@ 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");
+ cancel = get_signo ("__pthread_sig_cancel");
+
+ /* LinuxThreads normally uses the first two RT signals, but in some legacy
+ cases may use SIGUSR1/SIGUSR2. NPTL always uses RT signals, but does
+ not provide any way for the debugger to query the signal numbers -
+ fortunately they don't change! */
+
if (restart == 0)
- return;
+ restart = __SIGRTMIN;
- cancel = get_signo ("__pthread_sig_cancel");
if (cancel == 0)
- return;
+ cancel = __SIGRTMIN + 1;
sigaddset (set, restart);
sigaddset (set, cancel);
@@ -3148,7 +4326,7 @@ lin_thread_get_thread_signals (sigset_t *set)
action.sa_handler = sigchld_handler;
sigemptyset (&action.sa_mask);
- action.sa_flags = 0;
+ action.sa_flags = SA_RESTART;
sigaction (cancel, &action, NULL);
/* We block the "cancel" signal throughout this code ... */