/* GNU/Linux native-dependent code common to multiple platforms.
- Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
+ 2011 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "inferior.h"
#include "target.h"
-
+#include "gdb_string.h"
#include "gdb_wait.h"
+#include "gdb_assert.h"
+#ifdef HAVE_TKILL_SYSCALL
+#include <unistd.h>
+#include <sys/syscall.h>
+#endif
#include <sys/ptrace.h>
-
#include "linux-nat.h"
+#include "linux-ptrace.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 <sys/param.h> /* for MAXPATHLEN */
+#include <sys/procfs.h> /* for elf_gregset etc. */
+#include "elf-bfd.h" /* for elfcore_write_* */
+#include "gregset.h" /* for gregset */
+#include "gdbcore.h" /* for get_exec_file */
+#include <ctype.h> /* for isdigit */
+#include "gdbthread.h" /* for struct thread_info etc. */
+#include "gdb_stat.h" /* for struct stat */
+#include <fcntl.h> /* for O_RDONLY */
+#include "inf-loop.h"
+#include "event-loop.h"
+#include "event-top.h"
+#include <pwd.h>
+#include <sys/types.h>
+#include "gdb_dirent.h"
+#include "xml-support.h"
+#include "terminal.h"
+#include <sys/vfs.h>
+#include "solib.h"
-/* If the system headers did not provide the constants, hard-code the normal
- values. */
-#ifndef PTRACE_EVENT_FORK
-
-#define PTRACE_SETOPTIONS 0x4200
-#define PTRACE_GETEVENTMSG 0x4201
-
-/* options set using PTRACE_SETOPTIONS */
-#define PTRACE_O_TRACESYSGOOD 0x00000001
-#define PTRACE_O_TRACEFORK 0x00000002
-#define PTRACE_O_TRACEVFORK 0x00000004
-#define PTRACE_O_TRACECLONE 0x00000008
-#define PTRACE_O_TRACEEXEC 0x00000010
-#define PTRACE_O_TRACEVFORKDONE 0x00000020
-#define PTRACE_O_TRACEEXIT 0x00000040
-
-/* Wait extended result codes for the above trace options. */
-#define PTRACE_EVENT_FORK 1
-#define PTRACE_EVENT_VFORK 2
-#define PTRACE_EVENT_CLONE 3
-#define PTRACE_EVENT_EXEC 4
-#define PTRACE_EVENT_VFORKDONE 5
-#define PTRACE_EVENT_EXIT 6
-
-#endif /* PTRACE_EVENT_FORK */
-
-/* We can't always assume that this flag is available, but all systems
- with the ptrace event handlers also have __WALL, so it's safe to use
- here. */
-#ifndef __WALL
-#define __WALL 0x40000000 /* Wait for any child. */
+#ifndef SPUFS_MAGIC
+#define SPUFS_MAGIC 0x23c9b64e
+#endif
+
+#ifdef HAVE_PERSONALITY
+# include <sys/personality.h>
+# if !HAVE_DECL_ADDR_NO_RANDOMIZE
+# define ADDR_NO_RANDOMIZE 0x0040000
+# endif
+#endif /* HAVE_PERSONALITY */
+
+/* This comment documents high-level logic of this file.
+
+Waiting for events in sync mode
+===============================
+
+When waiting for an event in a specific thread, we just use waitpid, passing
+the specific pid, and not passing WNOHANG.
+
+When waiting for an event in all threads, waitpid is not quite good. Prior to
+version 2.4, Linux can either wait for event in main thread, or in secondary
+threads. (2.4 has the __WALL flag). So, if we use blocking waitpid, we might
+miss an event. The solution is to use non-blocking waitpid, together with
+sigsuspend. First, we use non-blocking waitpid to get an event in the main
+process, if any. Second, we use non-blocking waitpid with the __WCLONED
+flag to check for events in cloned processes. If nothing is found, we use
+sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, it means something
+happened to a child process -- and SIGCHLD will be delivered both for events
+in main debugged process and in cloned processes. As soon as we know there's
+an event, we get back to calling nonblocking waitpid with and without
+__WCLONED.
+
+Note that SIGCHLD should be blocked between waitpid and sigsuspend calls,
+so that we don't miss a signal. If SIGCHLD arrives in between, when it's
+blocked, the signal becomes pending and sigsuspend immediately
+notices it and returns.
+
+Waiting for events in async mode
+================================
+
+In async mode, GDB should always be ready to handle both user input
+and target events, so neither blocking waitpid nor sigsuspend are
+viable options. Instead, we should asynchronously notify the GDB main
+event loop whenever there's an unprocessed event from the target. We
+detect asynchronous target events by handling SIGCHLD signals. To
+notify the event loop about target events, the self-pipe trick is used
+--- a pipe is registered as waitable event source in the event loop,
+the event loop select/poll's on the read end of this pipe (as well on
+other event sources, e.g., stdin), and the SIGCHLD handler writes a
+byte to this pipe. This is more portable than relying on
+pselect/ppoll, since on kernels that lack those syscalls, libc
+emulates them with select/poll+sigprocmask, and that is racy
+(a.k.a. plain broken).
+
+Obviously, if we fail to notify the event loop if there's a target
+event, it's bad. OTOH, if we notify the event loop when there's no
+event from the target, linux_nat_wait will detect that there's no real
+event to report, and return event of type TARGET_WAITKIND_IGNORE.
+This is mostly harmless, but it will waste time and is better avoided.
+
+The main design point is that every time GDB is outside linux-nat.c,
+we have a SIGCHLD handler installed that is called when something
+happens to the target and notifies the GDB event loop. Whenever GDB
+core decides to handle the event, and calls into linux-nat.c, we
+process things as in sync mode, except that the we never block in
+sigsuspend.
+
+While processing an event, we may end up momentarily blocked in
+waitpid calls. Those waitpid calls, while blocking, are guarantied to
+return quickly. E.g., in all-stop mode, before reporting to the core
+that an LWP hit a breakpoint, all LWPs are stopped by sending them
+SIGSTOP, and synchronously waiting for the SIGSTOP to be reported.
+Note that this is different from blocking indefinitely waiting for the
+next event --- here, we're already handling an event.
+
+Use of signals
+==============
+
+We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another
+signal is not entirely significant; we just need for a signal to be delivered,
+so that we can intercept it. SIGSTOP's advantage is that it can not be
+blocked. A disadvantage is that it is not a real-time signal, so it can only
+be queued once; we do not keep track of other sources of SIGSTOP.
+
+Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't
+use them, because they have special behavior when the signal is generated -
+not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL
+kills the entire thread group.
+
+A delivered SIGSTOP would stop the entire thread group, not just the thread we
+tkill'd. But we never let the SIGSTOP be delivered; we always intercept and
+cancel it (by PTRACE_CONT without passing SIGSTOP).
+
+We could use a real-time signal instead. This would solve those problems; we
+could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB.
+But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH
+generates it, and there are races with trying to find a signal that is not
+blocked. */
+
+#ifndef O_LARGEFILE
+#define O_LARGEFILE 0
#endif
-extern struct target_ops child_ops;
+/* Unlike other extended result codes, WSTOPSIG (status) on
+ PTRACE_O_TRACESYSGOOD syscall events doesn't return SIGTRAP, but
+ instead SIGTRAP with bit 7 set. */
+#define SYSCALL_SIGTRAP (SIGTRAP | 0x80)
+
+/* The single-threaded native GNU/Linux target_ops. We save a pointer for
+ the use of the multi-threaded target. */
+static struct target_ops *linux_ops;
+static struct target_ops linux_ops_saved;
+
+/* The method to call, if any, when a new thread is attached. */
+static void (*linux_nat_new_thread) (ptid_t);
+
+/* The method to call, if any, when the siginfo object needs to be
+ converted between the layout returned by ptrace, and the layout in
+ the architecture of the inferior. */
+static int (*linux_nat_siginfo_fixup) (struct siginfo *,
+ gdb_byte *,
+ int);
+
+/* The saved to_xfer_partial method, inherited from inf-ptrace.c.
+ Called by our to_xfer_partial. */
+static LONGEST (*super_xfer_partial) (struct target_ops *,
+ 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 disable_randomization = 1;
-static int linux_parent_pid;
+static void
+show_disable_randomization (struct ui_file *file, int from_tty,
+ struct cmd_list_element *c, const char *value)
+{
+#ifdef HAVE_PERSONALITY
+ fprintf_filtered (file,
+ _("Disabling randomization of debuggee's "
+ "virtual address space is %s.\n"),
+ value);
+#else /* !HAVE_PERSONALITY */
+ fputs_filtered (_("Disabling randomization of debuggee's "
+ "virtual address space is unsupported on\n"
+ "this platform.\n"), file);
+#endif /* !HAVE_PERSONALITY */
+}
+
+static void
+set_disable_randomization (char *args, int from_tty,
+ struct cmd_list_element *c)
+{
+#ifndef HAVE_PERSONALITY
+ error (_("Disabling randomization of debuggee's "
+ "virtual address space is unsupported on\n"
+ "this platform."));
+#endif /* !HAVE_PERSONALITY */
+}
struct simple_pid_list
{
int pid;
+ int status;
struct simple_pid_list *next;
};
struct simple_pid_list *stopped_pids;
static int linux_supports_tracefork_flag = -1;
+/* This variable is a tri-state flag: -1 for unknown, 0 if
+ PTRACE_O_TRACESYSGOOD can not be used, 1 if it can. */
+
+static int linux_supports_tracesysgood_flag = -1;
+
/* If we have PTRACE_O_TRACEFORK, this flag indicates whether we also have
PTRACE_O_TRACEVFORKDONE. */
static int linux_supports_tracevforkdone_flag = -1;
+/* Stores the current used ptrace() options. */
+static int current_ptrace_options = 0;
+
+/* Async mode support. */
+
+/* The read/write ends of the pipe registered as waitable file in the
+ event loop. */
+static int linux_nat_event_pipe[2] = { -1, -1 };
+
+/* Flush the event pipe. */
+
+static void
+async_file_flush (void)
+{
+ int ret;
+ char buf;
+
+ do
+ {
+ ret = read (linux_nat_event_pipe[0], &buf, 1);
+ }
+ while (ret >= 0 || (ret == -1 && errno == EINTR));
+}
+
+/* Put something (anything, doesn't matter what, or how much) in event
+ pipe, so that the select/poll in the event-loop realizes we have
+ something to process. */
+
+static void
+async_file_mark (void)
+{
+ int ret;
+
+ /* It doesn't really matter what the pipe contains, as long we end
+ up with something in it. Might as well flush the previous
+ left-overs. */
+ async_file_flush ();
+
+ do
+ {
+ ret = write (linux_nat_event_pipe[1], "+", 1);
+ }
+ while (ret == -1 && errno == EINTR);
+
+ /* Ignore EAGAIN. If the pipe is full, the event loop will already
+ be awakened anyway. */
+}
+
+static void linux_nat_async (void (*callback)
+ (enum inferior_event_type event_type,
+ void *context),
+ void *context);
+static int kill_lwp (int lwpid, int signo);
+
+static int stop_callback (struct lwp_info *lp, void *data);
+
+static void block_child_signals (sigset_t *prev_mask);
+static void restore_child_signals_mask (sigset_t *prev_mask);
+
+struct lwp_info;
+static struct lwp_info *add_lwp (ptid_t ptid);
+static void purge_lwp_list (int pid);
+static struct lwp_info *find_lwp_pid (ptid_t ptid);
+
\f
/* 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 *statusp)
{
struct simple_pid_list **p;
if ((*p)->pid == pid)
{
struct simple_pid_list *next = (*p)->next;
+
+ *statusp = (*p)->status;
xfree (*p);
*p = next;
return 1;
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);
}
\f
static void
linux_tracefork_child (void)
{
- int ret;
-
ptrace (PTRACE_TRACEME, 0, 0, 0);
kill (getpid (), SIGSTOP);
fork ();
- exit (0);
+ _exit (0);
+}
+
+/* Wrapper function for waitpid which handles EINTR. */
+
+static int
+my_waitpid (int pid, int *statusp, int flags)
+{
+ int ret;
+
+ do
+ {
+ ret = waitpid (pid, statusp, flags);
+ }
+ while (ret == -1 && errno == EINTR);
+
+ return ret;
}
-/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events. We
+/* Determine if PTRACE_O_TRACEFORK can be used to follow fork events.
+
+ First, we try to enable fork tracing on ORIGINAL_PID. If this fails,
+ we know that the feature is not available. This may change the tracing
+ options for ORIGINAL_PID, but we'll be setting them shortly anyway.
+
+ However, if it succeeds, we don't know for sure that the feature is
+ available; old versions of PTRACE_SETOPTIONS ignored unknown options. We
create a child process, attach to it, use PTRACE_SETOPTIONS to enable
- fork tracing, and let it fork. If the process exits, we assume that
- we can't use TRACEFORK; if we get the fork notification, and we can
- extract the new child's PID, then we assume that we can. */
+ fork tracing, and let it fork. If the process exits, we assume that we
+ can't use TRACEFORK; if we get the fork notification, and we can extract
+ the new child's PID, then we assume that we can. */
static void
-linux_test_for_tracefork (void)
+linux_test_for_tracefork (int original_pid)
{
int child_pid, ret, status;
long second_pid;
+ sigset_t prev_mask;
+
+ /* We don't want those ptrace calls to be interrupted. */
+ block_child_signals (&prev_mask);
+
+ linux_supports_tracefork_flag = 0;
+ linux_supports_tracevforkdone_flag = 0;
+
+ ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK);
+ if (ret != 0)
+ {
+ restore_child_signals_mask (&prev_mask);
+ return;
+ }
child_pid = fork ();
if (child_pid == -1)
- perror_with_name ("linux_test_for_tracefork: fork");
+ perror_with_name (("fork"));
if (child_pid == 0)
linux_tracefork_child ();
- ret = waitpid (child_pid, &status, 0);
+ ret = my_waitpid (child_pid, &status, 0);
if (ret == -1)
- perror_with_name ("linux_test_for_tracefork: waitpid");
+ perror_with_name (("waitpid"));
else if (ret != child_pid)
- error ("linux_test_for_tracefork: waitpid: unexpected result %d.", ret);
+ error (_("linux_test_for_tracefork: waitpid: unexpected result %d."), ret);
if (! WIFSTOPPED (status))
- error ("linux_test_for_tracefork: waitpid: unexpected status %d.", status);
-
- linux_supports_tracefork_flag = 0;
+ error (_("linux_test_for_tracefork: waitpid: unexpected status %d."),
+ status);
ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0, PTRACE_O_TRACEFORK);
if (ret != 0)
{
- ptrace (PTRACE_KILL, child_pid, 0, 0);
- waitpid (child_pid, &status, 0);
+ ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
+ if (ret != 0)
+ {
+ warning (_("linux_test_for_tracefork: failed to kill child"));
+ restore_child_signals_mask (&prev_mask);
+ return;
+ }
+
+ ret = my_waitpid (child_pid, &status, 0);
+ if (ret != child_pid)
+ warning (_("linux_test_for_tracefork: failed "
+ "to wait for killed child"));
+ else if (!WIFSIGNALED (status))
+ warning (_("linux_test_for_tracefork: unexpected "
+ "wait status 0x%x from killed child"), status);
+
+ restore_child_signals_mask (&prev_mask);
return;
}
PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE);
linux_supports_tracevforkdone_flag = (ret == 0);
- ptrace (PTRACE_CONT, child_pid, 0, 0);
- ret = waitpid (child_pid, &status, 0);
+ ret = ptrace (PTRACE_CONT, child_pid, 0, 0);
+ if (ret != 0)
+ warning (_("linux_test_for_tracefork: failed to resume child"));
+
+ ret = my_waitpid (child_pid, &status, 0);
+
if (ret == child_pid && WIFSTOPPED (status)
&& status >> 16 == PTRACE_EVENT_FORK)
{
int second_status;
linux_supports_tracefork_flag = 1;
- waitpid (second_pid, &second_status, 0);
- ptrace (PTRACE_DETACH, second_pid, 0, 0);
+ my_waitpid (second_pid, &second_status, 0);
+ 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
+ warning (_("linux_test_for_tracefork: unexpected result from waitpid "
+ "(%d, status 0x%x)"), ret, status);
- if (WIFSTOPPED (status))
- {
- ptrace (PTRACE_DETACH, child_pid, 0, 0);
- waitpid (child_pid, &status, 0);
- }
+ ret = ptrace (PTRACE_KILL, child_pid, 0, 0);
+ if (ret != 0)
+ warning (_("linux_test_for_tracefork: failed to kill child"));
+ my_waitpid (child_pid, &status, 0);
+
+ restore_child_signals_mask (&prev_mask);
+}
+
+/* Determine if PTRACE_O_TRACESYSGOOD can be used to follow syscalls.
+
+ We try to enable syscall tracing on ORIGINAL_PID. If this fails,
+ we know that the feature is not available. This may change the tracing
+ options for ORIGINAL_PID, but we'll be setting them shortly anyway. */
+
+static void
+linux_test_for_tracesysgood (int original_pid)
+{
+ int ret;
+ sigset_t prev_mask;
+
+ /* We don't want those ptrace calls to be interrupted. */
+ block_child_signals (&prev_mask);
+
+ linux_supports_tracesysgood_flag = 0;
+
+ ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACESYSGOOD);
+ if (ret != 0)
+ goto out;
+
+ linux_supports_tracesysgood_flag = 1;
+out:
+ restore_child_signals_mask (&prev_mask);
+}
+
+/* Determine wether we support PTRACE_O_TRACESYSGOOD option available.
+ This function also sets linux_supports_tracesysgood_flag. */
+
+static int
+linux_supports_tracesysgood (int pid)
+{
+ if (linux_supports_tracesysgood_flag == -1)
+ linux_test_for_tracesysgood (pid);
+ return linux_supports_tracesysgood_flag;
}
/* Return non-zero iff we have tracefork functionality available.
This function also sets linux_supports_tracefork_flag. */
static int
-linux_supports_tracefork (void)
+linux_supports_tracefork (int pid)
{
if (linux_supports_tracefork_flag == -1)
- linux_test_for_tracefork ();
+ linux_test_for_tracefork (pid);
return linux_supports_tracefork_flag;
}
static int
-linux_supports_tracevforkdone (void)
+linux_supports_tracevforkdone (int pid)
{
if (linux_supports_tracefork_flag == -1)
- linux_test_for_tracefork ();
+ linux_test_for_tracefork (pid);
return linux_supports_tracevforkdone_flag;
}
+static void
+linux_enable_tracesysgood (ptid_t ptid)
+{
+ int pid = ptid_get_lwp (ptid);
+
+ if (pid == 0)
+ pid = ptid_get_pid (ptid);
+
+ if (linux_supports_tracesysgood (pid) == 0)
+ return;
+
+ current_ptrace_options |= PTRACE_O_TRACESYSGOOD;
+
+ ptrace (PTRACE_SETOPTIONS, pid, 0, current_ptrace_options);
+}
+
\f
void
linux_enable_event_reporting (ptid_t ptid)
{
- int pid = ptid_get_pid (ptid);
- int options;
+ int pid = ptid_get_lwp (ptid);
+
+ if (pid == 0)
+ pid = ptid_get_pid (ptid);
- if (! linux_supports_tracefork ())
+ if (! linux_supports_tracefork (pid))
return;
- options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC
- | PTRACE_O_TRACECLONE;
- if (linux_supports_tracevforkdone ())
- options |= PTRACE_O_TRACEVFORKDONE;
+ current_ptrace_options |= PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK
+ | PTRACE_O_TRACEEXEC | PTRACE_O_TRACECLONE;
+
+ if (linux_supports_tracevforkdone (pid))
+ current_ptrace_options |= PTRACE_O_TRACEVFORKDONE;
/* Do not enable PTRACE_O_TRACEEXIT until GDB is more prepared to support
read-only process state. */
- ptrace (PTRACE_SETOPTIONS, pid, 0, options);
+ ptrace (PTRACE_SETOPTIONS, pid, 0, current_ptrace_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 ();
+ linux_enable_tracesysgood (pid_to_ptid (pid));
}
-void
+static void
linux_child_post_startup_inferior (ptid_t ptid)
{
linux_enable_event_reporting (ptid);
+ check_for_thread_db ();
+ linux_enable_tracesysgood (ptid);
}
-#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;
+ sigset_t prev_mask;
int has_vforked;
int parent_pid, child_pid;
- get_last_target_status (&last_ptid, &last_status);
- has_vforked = (last_status.kind == TARGET_WAITKIND_VFORKED);
- parent_pid = ptid_get_pid (last_ptid);
- child_pid = last_status.value.related_pid;
+ block_child_signals (&prev_mask);
+
+ has_vforked = (inferior_thread ()->pending_follow.kind
+ == TARGET_WAITKIND_VFORKED);
+ parent_pid = ptid_get_lwp (inferior_ptid);
+ if (parent_pid == 0)
+ parent_pid = ptid_get_pid (inferior_ptid);
+ child_pid = PIDGET (inferior_thread ()->pending_follow.value.related_pid);
+
+ if (!detach_fork)
+ linux_enable_event_reporting (pid_to_ptid (child_pid));
+
+ if (has_vforked
+ && !non_stop /* Non-stop always resumes both branches. */
+ && (!target_is_async_p () || sync_execution)
+ && !(follow_child || detach_fork || sched_multi))
+ {
+ /* The parent stays blocked inside the vfork syscall until the
+ child execs or exits. If we don't let the child run, then
+ the parent stays blocked. If we're telling the parent to run
+ in the foreground, the user will not be able to ctrl-c to get
+ back the terminal, effectively hanging the debug session. */
+ fprintf_filtered (gdb_stderr, _("\
+Can not resume the parent process over vfork in the foreground while\n\
+holding the child stopped. Try \"set detach-on-fork\" or \
+\"set schedule-multiple\".\n"));
+ /* FIXME output string > 80 columns. */
+ return 1;
+ }
if (! follow_child)
{
- /* We're already attached to the parent, by default. */
+ struct lwp_info *child_lp = NULL;
+
+ /* We're already attached to the parent, by default. */
+
+ /* Detach new forked process? */
+ if (detach_fork)
+ {
+ /* Before detaching from the child, remove all breakpoints
+ from it. If we forked, then this has already been taken
+ care of by infrun.c. If we vforked however, any
+ breakpoint inserted in the parent is visible in the
+ child, even those added while stopped in a vfork
+ catchpoint. This will remove the breakpoints from the
+ parent also, but they'll be reinserted below. */
+ if (has_vforked)
+ {
+ /* keep breakpoints list in sync. */
+ remove_breakpoints_pid (GET_PID (inferior_ptid));
+ }
+
+ 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);
+ }
+ else
+ {
+ struct inferior *parent_inf, *child_inf;
+ struct cleanup *old_chain;
+
+ /* Add process to GDB's tables. */
+ child_inf = add_inferior (child_pid);
+
+ parent_inf = current_inferior ();
+ child_inf->attach_flag = parent_inf->attach_flag;
+ copy_terminal_info (child_inf, parent_inf);
+
+ old_chain = save_inferior_ptid ();
+ save_current_program_space ();
+
+ inferior_ptid = ptid_build (child_pid, child_pid, 0);
+ add_thread (inferior_ptid);
+ child_lp = add_lwp (inferior_ptid);
+ child_lp->stopped = 1;
+ child_lp->resumed = 1;
+
+ /* If this is a vfork child, then the address-space is
+ shared with the parent. */
+ if (has_vforked)
+ {
+ child_inf->pspace = parent_inf->pspace;
+ child_inf->aspace = parent_inf->aspace;
+
+ /* The parent will be frozen until the child is done
+ with the shared region. Keep track of the
+ parent. */
+ child_inf->vfork_parent = parent_inf;
+ child_inf->pending_detach = 0;
+ parent_inf->vfork_child = child_inf;
+ parent_inf->pending_detach = 0;
+ }
+ else
+ {
+ child_inf->aspace = new_address_space ();
+ child_inf->pspace = add_program_space (child_inf->aspace);
+ child_inf->removable = 1;
+ set_current_program_space (child_inf->pspace);
+ clone_program_space (child_inf->pspace, parent_inf->pspace);
- /* Before detaching from the child, remove all breakpoints from
- it. (This won't actually modify the breakpoint list, but will
- physically remove the breakpoints from the child.) */
- /* If we vforked this will remove the breakpoints from the parent
- also, but they'll be reinserted below. */
- detach_breakpoints (child_pid);
+ /* Let the shared library layer (solib-svr4) learn about
+ this new process, relocate the cloned exec, pull in
+ shared libraries, and install the solib event
+ breakpoint. If a "cloned-VM" event was propagated
+ better throughout the core, this wouldn't be
+ required. */
+ solib_create_inferior_hook (0);
+ }
- fprintf_filtered (gdb_stdout,
- "Detaching after fork from child process %d.\n",
- child_pid);
+ /* Let the thread_db layer learn about this new process. */
+ check_for_thread_db ();
- ptrace (PTRACE_DETACH, child_pid, 0, 0);
+ do_cleanups (old_chain);
+ }
if (has_vforked)
{
- if (linux_supports_tracevforkdone ())
+ struct lwp_info *lp;
+ struct inferior *parent_inf;
+
+ parent_inf = current_inferior ();
+
+ /* If we detached from the child, then we have to be careful
+ to not insert breakpoints in the parent until the child
+ is done with the shared memory region. However, if we're
+ staying attached to the child, then we can and should
+ insert breakpoints, so that we can debug it. A
+ subsequent child exec or exit is enough to know when does
+ the child stops using the parent's address space. */
+ parent_inf->waiting_for_vfork_done = detach_fork;
+ parent_inf->pspace->breakpoints_not_allowed = detach_fork;
+
+ lp = find_lwp_pid (pid_to_ptid (parent_pid));
+ gdb_assert (linux_supports_tracefork_flag >= 0);
+ if (linux_supports_tracevforkdone (0))
{
- int status;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LCFF: waiting for VFORK_DONE on %d\n",
+ parent_pid);
- ptrace (PTRACE_CONT, parent_pid, 0, 0);
- waitpid (parent_pid, &status, __WALL);
- if ((status >> 16) != PTRACE_EVENT_VFORKDONE)
- warning ("Unexpected waitpid result %06x when waiting for "
- "vfork-done", status);
+ lp->stopped = 1;
+ lp->resumed = 1;
+
+ /* We'll handle the VFORK_DONE event like any other
+ event, in target_wait. */
}
else
{
is only the single-step breakpoint at vfork's return
point. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LCFF: no VFORK_DONE "
+ "support, sleeping a bit\n");
+
usleep (10000);
- }
- /* Since we vforked, breakpoints were removed in the parent
- too. Put them back. */
- reattach_breakpoints (parent_pid);
+ /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event,
+ and leave it pending. The next linux_nat_resume call
+ will notice a pending event, and bypasses actually
+ resuming the inferior. */
+ lp->status = 0;
+ lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
+ lp->stopped = 0;
+ lp->resumed = 1;
+
+ /* If we're in async mode, need to tell the event loop
+ there's something here to process. */
+ if (target_can_async_p ())
+ async_file_mark ();
+ }
}
}
else
{
- char child_pid_spelling[40];
+ struct inferior *parent_inf, *child_inf;
+ struct lwp_info *lp;
+ struct program_space *parent_pspace;
- /* Needed to keep the breakpoint lists in sync. */
- if (! has_vforked)
- detach_breakpoints (child_pid);
+ if (info_verbose || debug_linux_nat)
+ {
+ target_terminal_ours ();
+ if (has_vforked)
+ fprintf_filtered (gdb_stdlog,
+ _("Attaching after process %d "
+ "vfork to child process %d.\n"),
+ parent_pid, child_pid);
+ else
+ fprintf_filtered (gdb_stdlog,
+ _("Attaching after process %d "
+ "fork to child process %d.\n"),
+ parent_pid, child_pid);
+ }
- /* Before detaching from the parent, remove all breakpoints from it. */
- remove_breakpoints ();
+ /* Add the new inferior first, so that the target_detach below
+ doesn't unpush the target. */
- fprintf_filtered (gdb_stdout,
- "Attaching after fork to child process %d.\n",
- child_pid);
+ child_inf = add_inferior (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
- breakpoints from the parent and detach it; at exit time we
- could do the same (or even, sneakily, resume debugging it - the
- child's exec has failed, or something similar).
+ parent_inf = current_inferior ();
+ child_inf->attach_flag = parent_inf->attach_flag;
+ copy_terminal_info (child_inf, parent_inf);
- This doesn't clean up "properly", because we can't call
- target_detach, but that's OK; if the current target is "child",
- then it doesn't need any further cleanups, and lin_lwp will
- generally not encounter vfork (vfork is defined to fork
- in libpthread.so).
+ parent_pspace = parent_inf->pspace;
- The holding part is very easy if we have VFORKDONE events;
- but keeping track of both processes is beyond GDB at the
- moment. So we don't expose the parent to the rest of GDB.
- Instead we quietly hold onto it until such time as we can
- safely resume it. */
+ /* If we're vforking, we want to hold on to the parent until the
+ child exits or execs. At child exec or exit time we can
+ remove the old breakpoints from the parent and detach or
+ resume debugging it. Otherwise, detach the parent now; we'll
+ want to reuse it's program/address spaces, but we can't set
+ them to the child before removing breakpoints from the
+ parent, otherwise, the breakpoints module could decide to
+ remove breakpoints from the wrong process (since they'd be
+ assigned to the same address space). */
if (has_vforked)
- linux_parent_pid = parent_pid;
- else
+ {
+ gdb_assert (child_inf->vfork_parent == NULL);
+ gdb_assert (parent_inf->vfork_child == NULL);
+ child_inf->vfork_parent = parent_inf;
+ child_inf->pending_detach = 0;
+ parent_inf->vfork_child = child_inf;
+ parent_inf->pending_detach = detach_fork;
+ parent_inf->waiting_for_vfork_done = 0;
+ }
+ else if (detach_fork)
target_detach (NULL, 0);
- inferior_ptid = pid_to_ptid (child_pid);
- push_target (&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;
+ /* Note that the detach above makes PARENT_INF dangling. */
- if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK
- || event == PTRACE_EVENT_CLONE)
- {
- unsigned long new_pid;
- int ret;
+ /* Add the child thread to the appropriate lists, and switch to
+ this new thread, before cloning the program space, and
+ informing the solib layer about this new process. */
- ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid);
+ inferior_ptid = ptid_build (child_pid, child_pid, 0);
+ add_thread (inferior_ptid);
+ lp = add_lwp (inferior_ptid);
+ lp->stopped = 1;
+ lp->resumed = 1;
- /* If we haven't already seen the new PID stop, wait for it now. */
- if (! pull_pid_from_list (&stopped_pids, new_pid))
+ /* If this is a vfork child, then the address-space is shared
+ with the parent. If we detached from the parent, then we can
+ reuse the parent's program/address spaces. */
+ if (has_vforked || 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);
+ child_inf->pspace = parent_pspace;
+ child_inf->aspace = child_inf->pspace->aspace;
}
-
- if (event == PTRACE_EVENT_FORK)
- ourstatus->kind = TARGET_WAITKIND_FORKED;
- else if (event == PTRACE_EVENT_VFORK)
- ourstatus->kind = TARGET_WAITKIND_VFORKED;
else
- ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
-
- ourstatus->value.related_pid = new_pid;
- return inferior_ptid;
- }
-
- if (event == PTRACE_EVENT_EXEC)
- {
- ourstatus->kind = TARGET_WAITKIND_EXECD;
- ourstatus->value.execd_pathname
- = xstrdup (child_pid_to_exec_file (pid));
-
- if (linux_parent_pid)
{
- detach_breakpoints (linux_parent_pid);
- ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0);
+ child_inf->aspace = new_address_space ();
+ child_inf->pspace = add_program_space (child_inf->aspace);
+ child_inf->removable = 1;
+ set_current_program_space (child_inf->pspace);
+ clone_program_space (child_inf->pspace, parent_pspace);
- linux_parent_pid = 0;
+ /* Let the shared library layer (solib-svr4) learn about
+ this new process, relocate the cloned exec, pull in
+ shared libraries, and install the solib event breakpoint.
+ If a "cloned-VM" event was propagated better throughout
+ the core, this wouldn't be required. */
+ solib_create_inferior_hook (0);
}
- return inferior_ptid;
+ /* Let the thread_db layer learn about this new process. */
+ check_for_thread_db ();
}
- internal_error (__FILE__, __LINE__,
- "unknown ptrace event %d", event);
+ restore_child_signals_mask (&prev_mask);
+ return 0;
}
\f
-int
-child_insert_fork_catchpoint (int pid)
+static int
+linux_child_insert_fork_catchpoint (int pid)
{
- if (! linux_supports_tracefork ())
- error ("Your system does not support fork catchpoints.");
+ return !linux_supports_tracefork (pid);
+}
+static int
+linux_child_remove_fork_catchpoint (int pid)
+{
return 0;
}
-int
-child_insert_vfork_catchpoint (int pid)
+static int
+linux_child_insert_vfork_catchpoint (int pid)
{
- if (!linux_supports_tracefork ())
- error ("Your system does not support vfork catchpoints.");
+ return !linux_supports_tracefork (pid);
+}
+static int
+linux_child_remove_vfork_catchpoint (int pid)
+{
return 0;
}
-int
-child_insert_exec_catchpoint (int pid)
+static int
+linux_child_insert_exec_catchpoint (int pid)
{
- if (!linux_supports_tracefork ())
- error ("Your system does not support exec catchpoints.");
+ return !linux_supports_tracefork (pid);
+}
+static int
+linux_child_remove_exec_catchpoint (int pid)
+{
return 0;
}
-void
-kill_inferior (void)
+static int
+linux_child_set_syscall_catchpoint (int pid, int needed, int any_count,
+ int table_size, int *table)
{
- int status;
- int pid = PIDGET (inferior_ptid);
- struct target_waitstatus last;
- ptid_t last_ptid;
- int ret;
+ if (!linux_supports_tracesysgood (pid))
+ return 1;
- if (pid == 0)
- return;
+ /* On GNU/Linux, we ignore the arguments. It means that we only
+ enable the syscall catchpoints, but do not disable them.
- /* 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. */
+ Also, we do not use the `table' information because we do not
+ filter system calls here. We let GDB do the logic for us. */
+ return 0;
+}
+
+/* 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
+ is almost entirely a user-space issue; the kernel doesn't enforce
+ such a grouping at all (this might change in the future). In
+ general, we'll rely on the threads library (i.e. the GNU/Linux
+ Threads library) to provide such a grouping.
+
+ It is perfectly well possible to write a multi-threaded application
+ without the assistance of a threads library, by using the clone
+ system call directly. This module should be able to give some
+ rudimentary support for debugging such applications if developers
+ specify the CLONE_PTRACE flag in the clone system call, and are
+ using the Linux kernel 2.4 or above.
+
+ Note that there are some peculiarities in GNU/Linux that affect
+ this code:
+
+ - In general one should specify the __WCLONE flag to waitpid in
+ order to make it report events for any of the cloned processes
+ (and leave it out for the initial process). However, if a cloned
+ process has exited the exit status is only reported if the
+ __WCLONE flag is absent. Linux kernel 2.4 has a __WALL flag, but
+ we cannot use it since GDB must work on older systems too.
+
+ - When a traced, cloned process exits and is waited for by the
+ debugger, the kernel reassigns it to the original parent and
+ keeps it around as a "zombie". Somehow, the GNU/Linux Threads
+ library doesn't notice this, which leads to the "zombie problem":
+ When debugged a multi-threaded process that spawns a lot of
+ threads will run out of processes, even if the threads exit,
+ because the "zombies" stay around. */
+
+/* List of known LWPs. */
+struct lwp_info *lwp_list;
+\f
+
+/* Original signal mask. */
+static sigset_t normal_mask;
+
+/* Signal mask for use with sigsuspend in linux_nat_wait, initialized in
+ _initialize_linux_nat. */
+static sigset_t suspend_mask;
+
+/* Signals to block to make that sigsuspend work. */
+static sigset_t blocked_mask;
+
+/* SIGCHLD action. */
+struct sigaction sigchld_action;
+
+/* Block child signals (SIGCHLD and linux threads signals), and store
+ the previous mask in PREV_MASK. */
+
+static void
+block_child_signals (sigset_t *prev_mask)
+{
+ /* Make sure SIGCHLD is blocked. */
+ if (!sigismember (&blocked_mask, SIGCHLD))
+ sigaddset (&blocked_mask, SIGCHLD);
+
+ sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask);
+}
+
+/* Restore child signals mask, previously returned by
+ block_child_signals. */
+
+static void
+restore_child_signals_mask (sigset_t *prev_mask)
+{
+ sigprocmask (SIG_SETMASK, prev_mask, NULL);
+}
+
+/* Mask of signals to pass directly to the inferior. */
+static sigset_t pass_mask;
+
+/* Update signals to pass to the inferior. */
+static void
+linux_nat_pass_signals (int numsigs, unsigned char *pass_signals)
+{
+ int signo;
+
+ sigemptyset (&pass_mask);
+
+ for (signo = 1; signo < NSIG; signo++)
+ {
+ int target_signo = target_signal_from_host (signo);
+ if (target_signo < numsigs && pass_signals[target_signo])
+ sigaddset (&pass_mask, signo);
+ }
+}
+
+\f
+
+/* Prototypes for local functions. */
+static int stop_wait_callback (struct lwp_info *lp, void *data);
+static int linux_thread_alive (ptid_t ptid);
+static char *linux_child_pid_to_exec_file (int pid);
+
+\f
+/* Convert wait status STATUS to a string. Used for printing debug
+ messages only. */
+
+static char *
+status_to_str (int status)
+{
+ static char buf[64];
+
+ if (WIFSTOPPED (status))
+ {
+ if (WSTOPSIG (status) == SYSCALL_SIGTRAP)
+ snprintf (buf, sizeof (buf), "%s (stopped at syscall)",
+ strsignal (SIGTRAP));
+ else
+ snprintf (buf, sizeof (buf), "%s (stopped)",
+ strsignal (WSTOPSIG (status)));
+ }
+ else if (WIFSIGNALED (status))
+ snprintf (buf, sizeof (buf), "%s (terminated)",
+ strsignal (WTERMSIG (status)));
+ else
+ snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status));
+
+ return buf;
+}
+
+/* Remove all LWPs belong to PID from the lwp list. */
+
+static void
+purge_lwp_list (int pid)
+{
+ struct lwp_info *lp, *lpprev, *lpnext;
+
+ lpprev = NULL;
+
+ for (lp = lwp_list; lp; lp = lpnext)
+ {
+ lpnext = lp->next;
+
+ if (ptid_get_pid (lp->ptid) == pid)
+ {
+ if (lp == lwp_list)
+ lwp_list = lp->next;
+ else
+ lpprev->next = lp->next;
+
+ xfree (lp);
+ }
+ else
+ lpprev = lp;
+ }
+}
+
+/* Return the number of known LWPs in the tgid given by PID. */
+
+static int
+num_lwps (int pid)
+{
+ int count = 0;
+ struct lwp_info *lp;
+
+ for (lp = lwp_list; lp; lp = lp->next)
+ if (ptid_get_pid (lp->ptid) == pid)
+ count++;
+
+ return count;
+}
+
+/* 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)
+{
+ struct lwp_info *lp;
+
+ gdb_assert (is_lwp (ptid));
+
+ lp = (struct lwp_info *) xmalloc (sizeof (struct lwp_info));
+
+ memset (lp, 0, sizeof (struct lwp_info));
+
+ lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+
+ lp->ptid = ptid;
+ lp->core = -1;
+
+ lp->next = lwp_list;
+ lwp_list = lp;
+
+ if (num_lwps (GET_PID (ptid)) > 1 && linux_nat_new_thread != NULL)
+ linux_nat_new_thread (ptid);
+
+ return lp;
+}
+
+/* Remove the LWP specified by PID from the list. */
+
+static void
+delete_lwp (ptid_t ptid)
+{
+ struct lwp_info *lp, *lpprev;
+
+ lpprev = NULL;
+
+ for (lp = lwp_list; lp; lpprev = lp, lp = lp->next)
+ if (ptid_equal (lp->ptid, ptid))
+ break;
+
+ if (!lp)
+ return;
+
+ if (lpprev)
+ lpprev->next = lp->next;
+ else
+ lwp_list = lp->next;
+
+ xfree (lp);
+}
+
+/* Return a pointer to the structure describing the LWP corresponding
+ to PID. If no corresponding LWP could be found, return NULL. */
+
+static struct lwp_info *
+find_lwp_pid (ptid_t ptid)
+{
+ struct lwp_info *lp;
+ int lwp;
+
+ if (is_lwp (ptid))
+ lwp = GET_LWP (ptid);
+ else
+ lwp = GET_PID (ptid);
+
+ for (lp = lwp_list; lp; lp = lp->next)
+ if (lwp == GET_LWP (lp->ptid))
+ return lp;
+
+ return NULL;
+}
+
+/* Call CALLBACK with its second argument set to DATA for every LWP in
+ the list. If CALLBACK returns 1 for a particular LWP, return a
+ pointer to the structure describing that LWP immediately.
+ Otherwise return NULL. */
+
+struct lwp_info *
+iterate_over_lwps (ptid_t filter,
+ int (*callback) (struct lwp_info *, void *),
+ void *data)
+{
+ struct lwp_info *lp, *lpnext;
+
+ for (lp = lwp_list; lp; lp = lpnext)
+ {
+ lpnext = lp->next;
+
+ if (ptid_match (lp->ptid, filter))
+ {
+ if ((*callback) (lp, data))
+ return lp;
+ }
+ }
+
+ return NULL;
+}
+
+/* Update our internal state when changing from one checkpoint 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
+linux_nat_switch_fork (ptid_t new_ptid)
+{
+ struct lwp_info *lp;
+
+ purge_lwp_list (GET_PID (inferior_ptid));
+
+ lp = add_lwp (new_ptid);
+ lp->stopped = 1;
+
+ /* This changes the thread's ptid while preserving the gdb thread
+ num. Also changes the inferior pid, while preserving the
+ inferior num. */
+ thread_change_ptid (inferior_ptid, new_ptid);
+
+ /* We've just told GDB core that the thread changed target id, but,
+ in fact, it really is a different thread, with different register
+ contents. */
+ registers_changed ();
+}
+
+/* Handle the exit of a single thread LP. */
+
+static void
+exit_lwp (struct lwp_info *lp)
+{
+ struct thread_info *th = find_thread_ptid (lp->ptid);
+
+ if (th)
+ {
+ if (print_thread_events)
+ printf_unfiltered (_("[%s exited]\n"), target_pid_to_str (lp->ptid));
+
+ delete_thread (lp->ptid);
+ }
+
+ delete_lwp (lp->ptid);
+}
+
+/* Return an lwp's tgid, found in `/proc/PID/status'. */
+
+int
+linux_proc_get_tgid (int lwpid)
+{
+ FILE *status_file;
+ char buf[100];
+ int tgid = -1;
+
+ snprintf (buf, sizeof (buf), "/proc/%d/status", (int) lwpid);
+ status_file = fopen (buf, "r");
+ if (status_file != NULL)
+ {
+ while (fgets (buf, sizeof (buf), status_file))
+ {
+ if (strncmp (buf, "Tgid:", 5) == 0)
+ {
+ tgid = strtoul (buf + strlen ("Tgid:"), NULL, 10);
+ break;
+ }
+ }
+
+ fclose (status_file);
+ }
+
+ return tgid;
+}
+
+/* Detect `T (stopped)' in `/proc/PID/status'.
+ Other states including `T (tracing stop)' are reported as false. */
+
+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))
+ {
+ if (strncmp (buf, "State:", 6) == 0)
+ {
+ have_state = 1;
+ break;
+ }
+ }
+ if (have_state && strstr (buf, "T (stopped)") != NULL)
+ retval = 1;
+ fclose (status_file);
+ }
+ return retval;
+}
+
+/* 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)
+{
+ pid_t new_pid, pid = GET_LWP (ptid);
+ int status;
+
+ 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. */
+ new_pid = my_waitpid (pid, &status, 0);
+ if (new_pid == -1 && errno == ECHILD)
+ {
+ if (first)
+ warning (_("%s is a cloned process"), target_pid_to_str (ptid));
+
+ /* Try again with __WCLONE to check cloned processes. */
+ new_pid = my_waitpid (pid, &status, __WCLONE);
+ *cloned = 1;
+ }
+
+ gdb_assert (pid == new_pid);
+
+ if (!WIFSTOPPED (status))
+ {
+ /* The pid we tried to attach has apparently just exited. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s",
+ pid, status_to_str (status));
+ return 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;
+ sigset_t prev_mask;
+
+ gdb_assert (is_lwp (ptid));
+
+ block_child_signals (&prev_mask);
+
+ 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));
+ restore_child_signals_mask (&prev_mask);
+ 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);
+ if (!WIFSTOPPED (status))
+ {
+ restore_child_signals_mask (&prev_mask);
+ return -1;
+ }
+
+ 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;
+ }
+
+ restore_child_signals_mask (&prev_mask);
+ return 0;
+}
+
+static void
+linux_nat_create_inferior (struct target_ops *ops,
+ char *exec_file, char *allargs, char **env,
+ int from_tty)
+{
+#ifdef HAVE_PERSONALITY
+ int personality_orig = 0, personality_set = 0;
+#endif /* HAVE_PERSONALITY */
+
+ /* The fork_child mechanism is synchronous and calls target_wait, so
+ we have to mask the async mode. */
+
+#ifdef HAVE_PERSONALITY
+ if (disable_randomization)
+ {
+ errno = 0;
+ personality_orig = personality (0xffffffff);
+ if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE))
+ {
+ personality_set = 1;
+ personality (personality_orig | ADDR_NO_RANDOMIZE);
+ }
+ if (errno != 0 || (personality_set
+ && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
+ warning (_("Error disabling address space randomization: %s"),
+ safe_strerror (errno));
+ }
+#endif /* HAVE_PERSONALITY */
+
+ /* Make sure we report all signals during startup. */
+ linux_nat_pass_signals (0, NULL);
+
+ linux_ops->to_create_inferior (ops, exec_file, allargs, env, from_tty);
+
+#ifdef HAVE_PERSONALITY
+ if (personality_set)
+ {
+ errno = 0;
+ personality (personality_orig);
+ if (errno != 0)
+ warning (_("Error restoring address space randomization: %s"),
+ safe_strerror (errno));
+ }
+#endif /* HAVE_PERSONALITY */
+}
+
+static void
+linux_nat_attach (struct target_ops *ops, char *args, int from_tty)
+{
+ struct lwp_info *lp;
+ int status;
+ ptid_t ptid;
+
+ /* Make sure we report all signals during attach. */
+ linux_nat_pass_signals (0, NULL);
+
+ linux_ops->to_attach (ops, args, from_tty);
+
+ /* The ptrace base target adds the main thread with (pid,0,0)
+ format. Decorate it with lwp info. */
+ ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
+ thread_change_ptid (inferior_ptid, ptid);
+
+ /* Add the initial process as the first LWP to the list. */
+ lp = add_lwp (ptid);
+
+ status = linux_nat_post_attach_wait (lp->ptid, 1, &lp->cloned,
+ &lp->signalled);
+ if (!WIFSTOPPED (status))
+ {
+ if (WIFEXITED (status))
+ {
+ int exit_code = WEXITSTATUS (status);
+
+ target_terminal_ours ();
+ target_mourn_inferior ();
+ if (exit_code == 0)
+ error (_("Unable to attach: program exited normally."));
+ else
+ error (_("Unable to attach: program exited with code %d."),
+ exit_code);
+ }
+ else if (WIFSIGNALED (status))
+ {
+ enum target_signal signo;
+
+ target_terminal_ours ();
+ target_mourn_inferior ();
+
+ signo = target_signal_from_host (WTERMSIG (status));
+ error (_("Unable to attach: program terminated with signal "
+ "%s, %s."),
+ target_signal_to_name (signo),
+ target_signal_to_string (signo));
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("unexpected status %d for PID %ld"),
+ status, (long) GET_LWP (ptid));
+ }
+
+ lp->stopped = 1;
+
+ /* 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));
+
+ lp->status = status;
+
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+}
+
+/* Get pending status of LP. */
+static int
+get_pending_status (struct lwp_info *lp, int *status)
+{
+ enum target_signal signo = TARGET_SIGNAL_0;
+
+ /* If we paused threads momentarily, we may have stored pending
+ events in lp->status or lp->waitstatus (see stop_wait_callback),
+ and GDB core hasn't seen any signal for those threads.
+ Otherwise, the last signal reported to the core is found in the
+ thread object's stop_signal.
+
+ There's a corner case that isn't handled here at present. Only
+ if the thread stopped with a TARGET_WAITKIND_STOPPED does
+ stop_signal make sense as a real signal to pass to the inferior.
+ Some catchpoint related events, like
+ TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set
+ to TARGET_SIGNAL_SIGTRAP when the catchpoint triggers. But,
+ those traps are debug API (ptrace in our case) related and
+ induced; the inferior wouldn't see them if it wasn't being
+ traced. Hence, we should never pass them to the inferior, even
+ when set to pass state. Since this corner case isn't handled by
+ infrun.c when proceeding with a signal, for consistency, neither
+ do we handle it here (or elsewhere in the file we check for
+ signal pass state). Normally SIGTRAP isn't set to pass state, so
+ this is really a corner case. */
+
+ if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
+ signo = TARGET_SIGNAL_0; /* a pending ptrace event, not a real signal. */
+ else if (lp->status)
+ signo = target_signal_from_host (WSTOPSIG (lp->status));
+ else if (non_stop && !is_executing (lp->ptid))
+ {
+ struct thread_info *tp = find_thread_ptid (lp->ptid);
+
+ signo = tp->suspend.stop_signal;
+ }
+ else if (!non_stop)
+ {
+ struct target_waitstatus last;
+ ptid_t last_ptid;
+
+ get_last_target_status (&last_ptid, &last);
+
+ if (GET_LWP (lp->ptid) == GET_LWP (last_ptid))
+ {
+ struct thread_info *tp = find_thread_ptid (lp->ptid);
+
+ signo = tp->suspend.stop_signal;
+ }
+ }
+
+ *status = 0;
+
+ if (signo == TARGET_SIGNAL_0)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "GPT: lwp %s has no pending signal\n",
+ target_pid_to_str (lp->ptid));
+ }
+ else if (!signal_pass_state (signo))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "GPT: lwp %s had signal %s, "
+ "but it is in no pass state\n",
+ target_pid_to_str (lp->ptid),
+ target_signal_to_string (signo));
+ }
+ else
+ {
+ *status = W_STOPCODE (target_signal_to_host (signo));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "GPT: lwp %s has pending signal %s\n",
+ target_pid_to_str (lp->ptid),
+ target_signal_to_string (signo));
+ }
+
+ return 0;
+}
+
+static int
+detach_callback (struct lwp_info *lp, void *data)
+{
+ gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
+
+ if (debug_linux_nat && lp->status)
+ fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n",
+ strsignal (WSTOPSIG (lp->status)),
+ target_pid_to_str (lp->ptid));
+
+ /* If there is a pending SIGSTOP, get rid of it. */
+ if (lp->signalled)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "DC: Sending SIGCONT to %s\n",
+ target_pid_to_str (lp->ptid));
+
+ kill_lwp (GET_LWP (lp->ptid), SIGCONT);
+ lp->signalled = 0;
+ }
+
+ /* We don't actually detach from the LWP that has an id equal to the
+ overall process id just yet. */
+ if (GET_LWP (lp->ptid) != GET_PID (lp->ptid))
+ {
+ int status = 0;
+
+ /* Pass on any pending signal for this LWP. */
+ get_pending_status (lp, &status);
+
+ errno = 0;
+ if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0,
+ WSTOPSIG (status)) < 0)
+ error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid),
+ safe_strerror (errno));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "PTRACE_DETACH (%s, %s, 0) (OK)\n",
+ target_pid_to_str (lp->ptid),
+ strsignal (WSTOPSIG (status)));
+
+ delete_lwp (lp->ptid);
+ }
+
+ return 0;
+}
+
+static void
+linux_nat_detach (struct target_ops *ops, char *args, int from_tty)
+{
+ int pid;
+ int status;
+ struct lwp_info *main_lwp;
+
+ pid = GET_PID (inferior_ptid);
+
+ if (target_can_async_p ())
+ linux_nat_async (NULL, 0);
+
+ /* Stop all threads before detaching. ptrace requires that the
+ thread is stopped to sucessfully detach. */
+ iterate_over_lwps (pid_to_ptid (pid), stop_callback, NULL);
+ /* ... and wait until all of them have reported back that
+ they're no longer running. */
+ iterate_over_lwps (pid_to_ptid (pid), stop_wait_callback, NULL);
+
+ iterate_over_lwps (pid_to_ptid (pid), detach_callback, NULL);
+
+ /* Only the initial process should be left right now. */
+ gdb_assert (num_lwps (GET_PID (inferior_ptid)) == 1);
+
+ main_lwp = find_lwp_pid (pid_to_ptid (pid));
+
+ /* Pass on any pending signal for the last LWP. */
+ if ((args == NULL || *args == '\0')
+ && get_pending_status (main_lwp, &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));
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LND: Sending signal %s to %s\n",
+ args,
+ target_pid_to_str (main_lwp->ptid));
+ }
+
+ delete_lwp (main_lwp->ptid);
+
+ if (forks_exist_p ())
+ {
+ /* Multi-fork case. The current inferior_ptid is being detached
+ from, but there are other viable forks to debug. Detach from
+ the current fork, and context-switch to the first
+ available. */
+ linux_fork_detach (args, from_tty);
+
+ if (non_stop && target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+ }
+ else
+ linux_ops->to_detach (ops, args, from_tty);
+}
+
+/* Resume LP. */
+
+static int
+resume_callback (struct lwp_info *lp, void *data)
+{
+ struct inferior *inf = find_inferior_pid (GET_PID (lp->ptid));
+
+ if (lp->stopped && inf->vfork_child != NULL)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: Not resuming %s (vfork parent)\n",
+ target_pid_to_str (lp->ptid));
+ }
+ else if (lp->stopped && lp->status == 0)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: PTRACE_CONT %s, 0, 0 (resuming sibling)\n",
+ target_pid_to_str (lp->ptid));
+
+ linux_ops->to_resume (linux_ops,
+ pid_to_ptid (GET_LWP (lp->ptid)),
+ 0, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "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));
+ lp->stopped_by_watchpoint = 0;
+ }
+ else if (lp->stopped && debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: Not resuming sibling %s (has pending)\n",
+ target_pid_to_str (lp->ptid));
+ else if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RC: Not resuming sibling %s (not stopped)\n",
+ target_pid_to_str (lp->ptid));
+
+ return 0;
+}
+
+static int
+resume_clear_callback (struct lwp_info *lp, void *data)
+{
+ lp->resumed = 0;
+ return 0;
+}
+
+static int
+resume_set_callback (struct lwp_info *lp, void *data)
+{
+ lp->resumed = 1;
+ return 0;
+}
+
+static void
+linux_nat_resume (struct target_ops *ops,
+ ptid_t ptid, int step, enum target_signal signo)
+{
+ sigset_t prev_mask;
+ struct lwp_info *lp;
+ int resume_many;
+
+ 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 != TARGET_SIGNAL_0
+ ? strsignal (target_signal_to_host (signo)) : "0"),
+ target_pid_to_str (inferior_ptid));
+
+ block_child_signals (&prev_mask);
+
+ /* A specific PTID means `step only this process id'. */
+ resume_many = (ptid_equal (minus_one_ptid, ptid)
+ || ptid_is_pid (ptid));
+
+ /* Mark the lwps we're resuming as resumed. */
+ iterate_over_lwps (ptid, resume_set_callback, NULL);
+
+ /* See if it's the current inferior that should be handled
+ specially. */
+ if (resume_many)
+ lp = find_lwp_pid (inferior_ptid);
+ else
+ lp = find_lwp_pid (ptid);
+ gdb_assert (lp != NULL);
+
+ /* Remember if we're stepping. */
+ lp->step = step;
+
+ /* If we have a pending wait status for this thread, there is no
+ point in resuming the process. But first make sure that
+ linux_nat_wait won't preemptively handle the event - we
+ should never take this short-circuit if we are going to
+ leave LP running, since we have skipped resuming all the
+ other threads. This bit of code needs to be synchronized
+ with linux_nat_wait. */
+
+ if (lp->status && WIFSTOPPED (lp->status))
+ {
+ if (!lp->step
+ && WSTOPSIG (lp->status)
+ && sigismember (&pass_mask, WSTOPSIG (lp->status)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Not short circuiting for ignored "
+ "status 0x%x\n", lp->status);
+
+ /* FIXME: What should we do if we are supposed to continue
+ this thread with a signal? */
+ gdb_assert (signo == TARGET_SIGNAL_0);
+ signo = target_signal_from_host (WSTOPSIG (lp->status));
+ lp->status = 0;
+ }
+ }
+
+ if (lp->status || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
+ {
+ /* 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);
+
+ restore_child_signals_mask (&prev_mask);
+ if (target_can_async_p ())
+ {
+ target_async (inferior_event_handler, 0);
+ /* Tell the event loop we have something to process. */
+ async_file_mark ();
+ }
+ return;
+ }
+
+ /* Mark LWP as not stopped to prevent it from being continued by
+ resume_callback. */
+ lp->stopped = 0;
+
+ if (resume_many)
+ iterate_over_lwps (ptid, resume_callback, NULL);
+
+ /* Convert to something the lower layer understands. */
+ ptid = pid_to_ptid (GET_LWP (lp->ptid));
+
+ linux_ops->to_resume (linux_ops, ptid, step, signo);
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
+ lp->stopped_by_watchpoint = 0;
+
+ 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 != TARGET_SIGNAL_0
+ ? strsignal (target_signal_to_host (signo)) : "0"));
+
+ restore_child_signals_mask (&prev_mask);
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+}
+
+/* Send a signal to an LWP. */
+
+static int
+kill_lwp (int lwpid, int signo)
+{
+ /* Use tkill, if possible, in case we are using nptl threads. If tkill
+ fails, then we are not using nptl threads and we should be using kill. */
+
+#ifdef HAVE_TKILL_SYSCALL
+ {
+ static int tkill_failed;
+
+ if (!tkill_failed)
+ {
+ int ret;
+
+ errno = 0;
+ ret = syscall (__NR_tkill, lwpid, signo);
+ if (errno != ENOSYS)
+ return ret;
+ tkill_failed = 1;
+ }
+ }
+#endif
+
+ return kill (lwpid, signo);
+}
+
+/* Handle a GNU/Linux syscall trap wait response. If we see a syscall
+ event, check if the core is interested in it: if not, ignore the
+ event, and keep waiting; otherwise, we need to toggle the LWP's
+ syscall entry/exit status, since the ptrace event itself doesn't
+ indicate it, and report the trap to higher layers. */
+
+static int
+linux_handle_syscall_trap (struct lwp_info *lp, int stopping)
+{
+ struct target_waitstatus *ourstatus = &lp->waitstatus;
+ struct gdbarch *gdbarch = target_thread_architecture (lp->ptid);
+ int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, lp->ptid);
+
+ if (stopping)
+ {
+ /* If we're stopping threads, there's a SIGSTOP pending, which
+ makes it so that the LWP reports an immediate syscall return,
+ followed by the SIGSTOP. Skip seeing that "return" using
+ PTRACE_CONT directly, and let stop_wait_callback collect the
+ SIGSTOP. Later when the thread is resumed, a new syscall
+ entry event. If we didn't do this (and returned 0), we'd
+ leave a syscall entry pending, and our caller, by using
+ PTRACE_CONT to collect the SIGSTOP, skips the syscall return
+ itself. Later, when the user re-resumes this LWP, we'd see
+ another syscall entry event and we'd mistake it for a return.
+
+ If stop_wait_callback didn't force the SIGSTOP out of the LWP
+ (leaving immediately with LWP->signalled set, without issuing
+ a PTRACE_CONT), it would still be problematic to leave this
+ syscall enter pending, as later when the thread is resumed,
+ it would then see the same syscall exit mentioned above,
+ followed by the delayed SIGSTOP, while the syscall didn't
+ actually get to execute. It seems it would be even more
+ confusing to the user. */
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHST: ignoring syscall %d "
+ "for LWP %ld (stopping threads), "
+ "resuming with PTRACE_CONT for SIGSTOP\n",
+ syscall_number,
+ GET_LWP (lp->ptid));
+
+ lp->syscall_state = TARGET_WAITKIND_IGNORE;
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ return 1;
+ }
+
+ if (catch_syscall_enabled ())
+ {
+ /* Always update the entry/return state, even if this particular
+ syscall isn't interesting to the core now. In async mode,
+ the user could install a new catchpoint for this syscall
+ between syscall enter/return, and we'll need to know to
+ report a syscall return if that happens. */
+ lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
+ ? TARGET_WAITKIND_SYSCALL_RETURN
+ : TARGET_WAITKIND_SYSCALL_ENTRY);
+
+ if (catching_syscall_number (syscall_number))
+ {
+ /* Alright, an event to report. */
+ ourstatus->kind = lp->syscall_state;
+ ourstatus->value.syscall_number = syscall_number;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHST: stopping for %s of syscall %d"
+ " for LWP %ld\n",
+ lp->syscall_state
+ == TARGET_WAITKIND_SYSCALL_ENTRY
+ ? "entry" : "return",
+ syscall_number,
+ GET_LWP (lp->ptid));
+ return 0;
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHST: ignoring %s of syscall %d "
+ "for LWP %ld\n",
+ lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
+ ? "entry" : "return",
+ syscall_number,
+ GET_LWP (lp->ptid));
+ }
+ else
+ {
+ /* If we had been syscall tracing, and hence used PT_SYSCALL
+ before on this LWP, it could happen that the user removes all
+ syscall catchpoints before we get to process this event.
+ There are two noteworthy issues here:
+
+ - When stopped at a syscall entry event, resuming with
+ PT_STEP still resumes executing the syscall and reports a
+ syscall return.
+
+ - Only PT_SYSCALL catches syscall enters. If we last
+ single-stepped this thread, then this event can't be a
+ syscall enter. If we last single-stepped this thread, this
+ has to be a syscall exit.
+
+ The points above mean that the next resume, be it PT_STEP or
+ PT_CONTINUE, can not trigger a syscall trace event. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHST: caught syscall event "
+ "with no syscall catchpoints."
+ " %d for LWP %ld, ignoring\n",
+ syscall_number,
+ GET_LWP (lp->ptid));
+ lp->syscall_state = TARGET_WAITKIND_IGNORE;
+ }
+
+ /* The core isn't interested in this event. For efficiency, avoid
+ stopping all threads only to have the core resume them all again.
+ Since we're not stopping threads, if we're still syscall tracing
+ and not stepping, we can't use PTRACE_CONT here, as we'd miss any
+ subsequent syscall. Simply resume using the inf-ptrace layer,
+ which knows when to use PT_SYSCALL or PT_CONTINUE. */
+
+ /* Note that gdbarch_get_syscall_number may access registers, hence
+ fill a regcache. */
+ registers_changed ();
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ return 1;
+}
+
+/* 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_handle_extended_wait (struct lwp_info *lp, int status,
+ int stopping)
+{
+ int pid = GET_LWP (lp->ptid);
+ struct target_waitstatus *ourstatus = &lp->waitstatus;
+ 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, &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);
+ }
+
+ ourstatus->value.related_pid = ptid_build (new_pid, new_pid, 0);
+
+ if (event == PTRACE_EVENT_FORK
+ && linux_fork_checkpointing_p (GET_PID (lp->ptid)))
+ {
+ /* Handle checkpointing by linux-fork.c here as a special
+ case. We don't want the follow-fork-mode or 'catch fork'
+ to interfere with this. */
+
+ /* This won't actually modify the breakpoint list, but will
+ physically remove the breakpoints from the child. */
+ detach_breakpoints (new_pid);
+
+ /* Retain child fork in ptrace (stopped) state. */
+ if (!find_fork_pid (new_pid))
+ add_fork (new_pid);
+
+ /* Report as spurious, so that infrun doesn't want to follow
+ this fork. We're actually doing an infcall in
+ linux-fork.c. */
+ ourstatus->kind = TARGET_WAITKIND_SPURIOUS;
+ linux_enable_event_reporting (pid_to_ptid (new_pid));
+
+ /* Report the stop to the core. */
+ return 0;
+ }
+
+ if (event == PTRACE_EVENT_FORK)
+ ourstatus->kind = TARGET_WAITKIND_FORKED;
+ else if (event == PTRACE_EVENT_VFORK)
+ ourstatus->kind = TARGET_WAITKIND_VFORKED;
+ else
+ {
+ struct lwp_info *new_lp;
+
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
+ new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (lp->ptid)));
+ new_lp->cloned = 1;
+ new_lp->stopped = 1;
+
+ if (WSTOPSIG (status) != SIGSTOP)
+ {
+ /* This can happen if someone starts sending signals to
+ the new thread before it gets a chance to run, which
+ have a lower number than SIGSTOP (e.g. SIGUSR1).
+ This is an unlikely case, and harder to handle for
+ fork / vfork than for clone, so we do not try - but
+ we handle it for clone events here. We'll send
+ the other signal on to the thread below. */
+
+ new_lp->signalled = 1;
+ }
+ else
+ status = 0;
+
+ if (non_stop)
+ {
+ /* Add the new thread to GDB's lists as soon as possible
+ so that:
+
+ 1) the frontend doesn't have to wait for a stop to
+ display them, and,
+
+ 2) we tag it with the correct running state. */
+
+ /* If the thread_db layer is active, let it know about
+ this new thread, and add it to GDB's list. */
+ if (!thread_db_attach_lwp (new_lp->ptid))
+ {
+ /* We're not using thread_db. Add it to GDB's
+ list. */
+ target_post_attach (GET_LWP (new_lp->ptid));
+ add_thread (new_lp->ptid);
+ }
+
+ if (!stopping)
+ {
+ set_running (new_lp->ptid, 1);
+ set_executing (new_lp->ptid, 1);
+ }
+ }
+
+ /* Note the need to use the low target ops to resume, to
+ handle resuming with PT_SYSCALL if we have syscall
+ catchpoints. */
+ if (!stopping)
+ {
+ enum target_signal signo;
+
+ new_lp->stopped = 0;
+ new_lp->resumed = 1;
+
+ signo = (status
+ ? target_signal_from_host (WSTOPSIG (status))
+ : TARGET_SIGNAL_0);
+
+ linux_ops->to_resume (linux_ops, pid_to_ptid (new_pid),
+ 0, signo);
+ }
+ else
+ {
+ if (status != 0)
+ {
+ /* We created NEW_LP so it cannot yet contain STATUS. */
+ gdb_assert (new_lp->status == 0);
+
+ /* Save the wait status to report later. */
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: waitpid of new LWP %ld, "
+ "saving status %s\n",
+ (long) GET_LWP (new_lp->ptid),
+ status_to_str (status));
+ new_lp->status = status;
+ }
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got clone event "
+ "from LWP %ld, resuming\n",
+ GET_LWP (lp->ptid));
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ 0, TARGET_SIGNAL_0);
+
+ return 1;
+ }
+
+ return 0;
+ }
+
+ if (event == PTRACE_EVENT_EXEC)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got exec event from LWP %ld\n",
+ GET_LWP (lp->ptid));
+
+ ourstatus->kind = TARGET_WAITKIND_EXECD;
+ ourstatus->value.execd_pathname
+ = xstrdup (linux_child_pid_to_exec_file (pid));
+
+ return 0;
+ }
+
+ if (event == PTRACE_EVENT_VFORK_DONE)
+ {
+ if (current_inferior ()->waiting_for_vfork_done)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got expected PTRACE_EVENT_"
+ "VFORK_DONE from LWP %ld: stopping\n",
+ GET_LWP (lp->ptid));
+
+ ourstatus->kind = TARGET_WAITKIND_VFORK_DONE;
+ return 0;
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got PTRACE_EVENT_VFORK_DONE "
+ "from LWP %ld: resuming\n",
+ GET_LWP (lp->ptid));
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ return 1;
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("unknown ptrace event %d"), event);
+}
+
+/* Return non-zero if LWP is a zombie. */
+
+static int
+linux_lwp_is_zombie (long lwp)
+{
+ char buffer[MAXPATHLEN];
+ FILE *procfile;
+ int retval = 0;
+
+ xsnprintf (buffer, sizeof (buffer), "/proc/%ld/status", lwp);
+ procfile = fopen (buffer, "r");
+ if (procfile == NULL)
+ {
+ warning (_("unable to open /proc file '%s'"), buffer);
+ return 0;
+ }
+ while (fgets (buffer, sizeof (buffer), procfile) != NULL)
+ if (strcmp (buffer, "State:\tZ (zombie)\n") == 0)
+ {
+ retval = 1;
+ break;
+ }
+ fclose (procfile);
+
+ return retval;
+}
+
+/* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
+ exited. */
+
+static int
+wait_lwp (struct lwp_info *lp)
+{
+ pid_t pid;
+ int status = 0;
+ int thread_dead = 0;
+ sigset_t prev_mask;
+
+ gdb_assert (!lp->stopped);
+ gdb_assert (lp->status == 0);
+
+ /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */
+ block_child_signals (&prev_mask);
+
+ for (;;)
+ {
+ /* If my_waitpid returns 0 it means the __WCLONE vs. non-__WCLONE kind
+ was right and we should just call sigsuspend. */
+
+ pid = my_waitpid (GET_LWP (lp->ptid), &status, WNOHANG);
+ if (pid == -1 && errno == ECHILD)
+ pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE | WNOHANG);
+ if (pid != 0)
+ break;
+
+ /* Bugs 10970, 12702.
+ Thread group leader may have exited in which case we'll lock up in
+ waitpid if there are other threads, even if they are all zombies too.
+ Basically, we're not supposed to use waitpid this way.
+ __WCLONE is not applicable for the leader so we can't use that.
+ LINUX_NAT_THREAD_ALIVE cannot be used here as it requires a STOPPED
+ process; it gets ESRCH both for the zombie and for running processes.
+
+ As a workaround, check if we're waiting for the thread group leader and
+ if it's a zombie, and avoid calling waitpid if it is.
+
+ This is racy, what if the tgl becomes a zombie right after we check?
+ Therefore always use WNOHANG with sigsuspend - it is equivalent to
+ waiting waitpid but the linux_lwp_is_zombie is safe this way. */
+
+ if (GET_PID (lp->ptid) == GET_LWP (lp->ptid)
+ && linux_lwp_is_zombie (GET_LWP (lp->ptid)))
+ {
+ thread_dead = 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "WL: Thread group leader %s vanished.\n",
+ target_pid_to_str (lp->ptid));
+ break;
+ }
+
+ /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers
+ get invoked despite our caller had them intentionally blocked by
+ block_child_signals. This is sensitive only to the loop of
+ linux_nat_wait_1 and there if we get called my_waitpid gets called
+ again before it gets to sigsuspend so we can safely let the handlers
+ get executed here. */
+
+ sigsuspend (&suspend_mask);
+ }
+
+ restore_child_signals_mask (&prev_mask);
+
+ if (pid == -1 && errno == ECHILD)
+ {
+ /* The thread has previously exited. We need to delete it
+ now because, for some vendor 2.4 kernels with NPTL
+ support backported, there won't be an exit event unless
+ it is the main thread. 2.6 kernels will report an exit
+ event for each thread that exits, as expected. */
+ thread_dead = 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n",
+ target_pid_to_str (lp->ptid));
+ }
+
+ if (!thread_dead)
+ {
+ gdb_assert (pid == GET_LWP (lp->ptid));
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "WL: waitpid %s received %s\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str (status));
+ }
+ }
+
+ /* Check if the thread has exited. */
+ if (WIFEXITED (status) || WIFSIGNALED (status))
+ {
+ thread_dead = 1;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+ }
+
+ if (thread_dead)
+ {
+ exit_lwp (lp);
+ return 0;
+ }
+
+ gdb_assert (WIFSTOPPED (status));
+
+ /* Handle GNU/Linux's syscall SIGTRAPs. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP)
+ {
+ /* No longer need the sysgood bit. The ptrace event ends up
+ recorded in lp->waitstatus if we care for it. We can carry
+ on handling the event like a regular SIGTRAP from here
+ on. */
+ status = W_STOPCODE (SIGTRAP);
+ if (linux_handle_syscall_trap (lp, 1))
+ return wait_lwp (lp);
+ }
+
+ /* Handle GNU/Linux's extended waitstatus for trace events. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "WL: Handling extended status 0x%06x\n",
+ 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
+stop_callback (struct lwp_info *lp, void *data)
+{
+ if (!lp->stopped && !lp->signalled)
+ {
+ int ret;
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "SC: kill %s **<SIGSTOP>**\n",
+ target_pid_to_str (lp->ptid));
+ }
+ errno = 0;
+ ret = kill_lwp (GET_LWP (lp->ptid), SIGSTOP);
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "SC: lwp kill %d %s\n",
+ ret,
+ errno ? safe_strerror (errno) : "ERRNO-OK");
+ }
+
+ lp->signalled = 1;
+ gdb_assert (lp->status == 0);
+ }
+
+ return 0;
+}
+
+/* Return non-zero if LWP PID has a pending SIGINT. */
+
+static int
+linux_nat_has_pending_sigint (int pid)
+{
+ sigset_t pending, blocked, ignored;
+
+ linux_proc_pending_signals (pid, &pending, &blocked, &ignored);
+
+ if (sigismember (&pending, SIGINT)
+ && !sigismember (&ignored, SIGINT))
+ return 1;
+
+ return 0;
+}
+
+/* Set a flag in LP indicating that we should ignore its next SIGINT. */
+
+static int
+set_ignore_sigint (struct lwp_info *lp, void *data)
+{
+ /* If a thread has a pending SIGINT, consume it; otherwise, set a
+ flag to consume the next one. */
+ if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status)
+ && WSTOPSIG (lp->status) == SIGINT)
+ lp->status = 0;
+ else
+ lp->ignore_sigint = 1;
+
+ return 0;
+}
+
+/* If LP does not have a SIGINT pending, then clear the ignore_sigint flag.
+ This function is called after we know the LWP has stopped; if the LWP
+ stopped before the expected SIGINT was delivered, then it will never have
+ arrived. Also, if the signal was delivered to a shared queue and consumed
+ by a different thread, it will never be delivered to this LWP. */
+
+static void
+maybe_clear_ignore_sigint (struct lwp_info *lp)
+{
+ if (!lp->ignore_sigint)
+ return;
+
+ if (!linux_nat_has_pending_sigint (GET_LWP (lp->ptid)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "MCIS: Clearing bogus flag for %s\n",
+ target_pid_to_str (lp->ptid));
+ lp->ignore_sigint = 0;
+ }
+}
+
+/* Fetch the possible triggered data watchpoint info and store it in
+ LP.
+
+ On some archs, like x86, that use debug registers to set
+ watchpoints, it's possible that the way to know which watched
+ address trapped, is to check the register that is used to select
+ which address to watch. Problem is, between setting the watchpoint
+ and reading back which data address trapped, the user may change
+ the set of watchpoints, and, as a consequence, GDB changes the
+ debug registers in the inferior. To avoid reading back a stale
+ stopped-data-address when that happens, we cache in LP the fact
+ that a watchpoint trapped, and the corresponding data address, as
+ soon as we see LP stop with a SIGTRAP. If GDB changes the debug
+ registers meanwhile, we have the cached data we can rely on. */
+
+static void
+save_sigtrap (struct lwp_info *lp)
+{
+ struct cleanup *old_chain;
+
+ if (linux_ops->to_stopped_by_watchpoint == NULL)
+ {
+ lp->stopped_by_watchpoint = 0;
+ return;
+ }
+
+ old_chain = save_inferior_ptid ();
+ inferior_ptid = lp->ptid;
+
+ lp->stopped_by_watchpoint = linux_ops->to_stopped_by_watchpoint ();
+
+ if (lp->stopped_by_watchpoint)
+ {
+ if (linux_ops->to_stopped_data_address != NULL)
+ lp->stopped_data_address_p =
+ linux_ops->to_stopped_data_address (¤t_target,
+ &lp->stopped_data_address);
+ else
+ lp->stopped_data_address_p = 0;
+ }
+
+ do_cleanups (old_chain);
+}
+
+/* See save_sigtrap. */
+
+static int
+linux_nat_stopped_by_watchpoint (void)
+{
+ struct lwp_info *lp = find_lwp_pid (inferior_ptid);
+
+ gdb_assert (lp != NULL);
+
+ return lp->stopped_by_watchpoint;
+}
+
+static int
+linux_nat_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p)
+{
+ struct lwp_info *lp = find_lwp_pid (inferior_ptid);
+
+ gdb_assert (lp != NULL);
+
+ *addr_p = lp->stopped_data_address;
+
+ return lp->stopped_data_address_p;
+}
+
+/* Commonly any breakpoint / watchpoint generate only SIGTRAP. */
+
+static int
+sigtrap_is_event (int status)
+{
+ return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP;
+}
+
+/* SIGTRAP-like events recognizer. */
+
+static int (*linux_nat_status_is_event) (int status) = sigtrap_is_event;
+
+/* Check for SIGTRAP-like events in LP. */
+
+static int
+linux_nat_lp_status_is_event (struct lwp_info *lp)
+{
+ /* We check for lp->waitstatus in addition to lp->status, because we can
+ have pending process exits recorded in lp->status
+ and W_EXITCODE(0,0) == 0. We should probably have an additional
+ lp->status_p flag. */
+
+ return (lp->waitstatus.kind == TARGET_WAITKIND_IGNORE
+ && linux_nat_status_is_event (lp->status));
+}
+
+/* Set alternative SIGTRAP-like events recognizer. If
+ breakpoint_inserted_here_p there then gdbarch_decr_pc_after_break will be
+ applied. */
+
+void
+linux_nat_set_status_is_event (struct target_ops *t,
+ int (*status_is_event) (int status))
+{
+ linux_nat_status_is_event = status_is_event;
+}
+
+/* Wait until LP is stopped. */
+
+static int
+stop_wait_callback (struct lwp_info *lp, void *data)
+{
+ struct inferior *inf = find_inferior_pid (GET_PID (lp->ptid));
+
+ /* If this is a vfork parent, bail out, it is not going to report
+ any SIGSTOP until the vfork is done with. */
+ if (inf->vfork_child != NULL)
+ return 0;
+
+ if (!lp->stopped)
+ {
+ int status;
+
+ status = wait_lwp (lp);
+ if (status == 0)
+ return 0;
+
+ if (lp->ignore_sigint && WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGINT)
+ {
+ lp->ignore_sigint = 0;
+
+ errno = 0;
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "PTRACE_CONT %s, 0, 0 (%s) "
+ "(discarding SIGINT)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ return stop_wait_callback (lp, NULL);
+ }
+
+ maybe_clear_ignore_sigint (lp);
+
+ if (WSTOPSIG (status) != SIGSTOP)
+ {
+ if (linux_nat_status_is_event (status))
+ {
+ /* If a LWP other than the LWP that we're reporting an
+ event for has hit a GDB breakpoint (as opposed to
+ some random trap signal), then just arrange for it to
+ hit it again later. We don't keep the SIGTRAP status
+ and don't forward the SIGTRAP signal to the LWP. We
+ will handle the current event, eventually we will
+ resume all LWPs, and this one will get its breakpoint
+ trap again.
+
+ If we do not do this, then we run the risk that the
+ user will delete or disable the breakpoint, but the
+ thread will have already tripped on it. */
+
+ /* Save the trap's siginfo in case we need it later. */
+ save_siginfo (lp);
+
+ save_sigtrap (lp);
+
+ /* Now resume this LWP and get the SIGSTOP event. */
+ errno = 0;
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "PTRACE_CONT %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ fprintf_unfiltered (gdb_stdlog,
+ "SWC: Candidate SIGTRAP event in %s\n",
+ target_pid_to_str (lp->ptid));
+ }
+ /* Hold this event/waitstatus while we check to see if
+ there are any more (we still want to get that SIGSTOP). */
+ stop_wait_callback (lp, NULL);
+
+ /* 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
+ {
+ /* The thread was stopped with a signal other than
+ SIGSTOP, and didn't accidentally trip a breakpoint. */
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "SWC: Pending event %s in %s\n",
+ status_to_str ((int) status),
+ target_pid_to_str (lp->ptid));
+ }
+ /* Now resume this LWP and get the SIGSTOP event. */
+ errno = 0;
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "SWC: PTRACE_CONT %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ /* Hold this event/waitstatus while we check to see if
+ there are any more (we still want to get that SIGSTOP). */
+ stop_wait_callback (lp, NULL);
+
+ /* If 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)
+ {
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "SWC: kill %s, %s\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str ((int) status));
+ }
+ kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (status));
+ }
+ else
+ lp->status = status;
+ return 0;
+ }
+ }
+ else
+ {
+ /* We caught the SIGSTOP that we intended to catch, so
+ there's no SIGSTOP pending. */
+ lp->stopped = 1;
+ lp->signalled = 0;
+ }
+ }
+
+ return 0;
+}
+
+/* Return non-zero if LP has a wait status pending. */
+
+static int
+status_callback (struct lwp_info *lp, void *data)
+{
+ /* Only report a pending wait status if we pretend that this has
+ indeed been resumed. */
+ if (!lp->resumed)
+ return 0;
+
+ if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
+ {
+ /* A ptrace event, like PTRACE_FORK|VFORK|EXEC, syscall event,
+ or a pending process exit. Note that `W_EXITCODE(0,0) ==
+ 0', so a clean process exit can not be stored pending in
+ lp->status, it is indistinguishable from
+ no-pending-status. */
+ return 1;
+ }
+
+ if (lp->status != 0)
+ return 1;
+
+ return 0;
+}
+
+/* Return non-zero if LP isn't stopped. */
+
+static int
+running_callback (struct lwp_info *lp, void *data)
+{
+ return (lp->stopped == 0 || (lp->status != 0 && lp->resumed));
+}
+
+/* Count the LWP's that have had events. */
+
+static int
+count_events_callback (struct lwp_info *lp, void *data)
+{
+ int *count = data;
+
+ gdb_assert (count != NULL);
+
+ /* Count only resumed LWPs that have a SIGTRAP event pending. */
+ if (lp->resumed && linux_nat_lp_status_is_event (lp))
+ (*count)++;
+
+ return 0;
+}
+
+/* Select the LWP (if any) that is currently being single-stepped. */
+
+static int
+select_singlestep_lwp_callback (struct lwp_info *lp, void *data)
+{
+ if (lp->step && lp->status != 0)
+ return 1;
+ else
+ return 0;
+}
+
+/* Select the Nth LWP that has had a SIGTRAP event. */
+
+static int
+select_event_lwp_callback (struct lwp_info *lp, void *data)
+{
+ int *selector = data;
+
+ gdb_assert (selector != NULL);
+
+ /* Select only resumed LWPs that have a SIGTRAP event pending. */
+ if (lp->resumed && linux_nat_lp_status_is_event (lp))
+ if ((*selector)-- == 0)
+ return 1;
+
+ return 0;
+}
+
+static int
+cancel_breakpoint (struct lwp_info *lp)
+{
+ /* Arrange for a breakpoint to be hit again later. We don't keep
+ the SIGTRAP status and don't forward the SIGTRAP signal to the
+ LWP. We will handle the current event, eventually we will resume
+ this LWP, and this breakpoint will trap again.
+
+ If we do not do this, then we run the risk that the user will
+ delete or disable the breakpoint, but the LWP will have already
+ tripped on it. */
+
+ struct regcache *regcache = get_thread_regcache (lp->ptid);
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ CORE_ADDR pc;
+
+ pc = regcache_read_pc (regcache) - gdbarch_decr_pc_after_break (gdbarch);
+ if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "CB: Push back breakpoint for %s\n",
+ target_pid_to_str (lp->ptid));
+
+ /* Back up the PC if necessary. */
+ if (gdbarch_decr_pc_after_break (gdbarch))
+ regcache_write_pc (regcache, pc);
+
+ return 1;
+ }
+ return 0;
+}
+
+static int
+cancel_breakpoints_callback (struct lwp_info *lp, void *data)
+{
+ struct lwp_info *event_lp = data;
+
+ /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
+ if (lp == event_lp)
+ return 0;
+
+ /* If a LWP other than the LWP that we're reporting an event for has
+ hit a GDB breakpoint (as opposed to some random trap signal),
+ then just arrange for it to hit it again later. We don't keep
+ the SIGTRAP status and don't forward the SIGTRAP signal to the
+ LWP. We will handle the current event, eventually we will resume
+ all LWPs, and this one will get its breakpoint trap again.
+
+ If we do not do this, then we run the risk that the user will
+ delete or disable the breakpoint, but the LWP will have already
+ tripped on it. */
+
+ if (linux_nat_lp_status_is_event (lp)
+ && cancel_breakpoint (lp))
+ /* Throw away the SIGTRAP. */
+ lp->status = 0;
+
+ return 0;
+}
+
+/* Select one LWP out of those that have events pending. */
+
+static void
+select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status)
+{
+ int num_events = 0;
+ int random_selector;
+ struct lwp_info *event_lp;
+
+ /* Record the wait status for the original LWP. */
+ (*orig_lp)->status = *status;
+
+ /* Give preference to any LWP that is being single-stepped. */
+ event_lp = iterate_over_lwps (filter,
+ select_singlestep_lwp_callback, NULL);
+ if (event_lp != NULL)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "SEL: Select single-step %s\n",
+ target_pid_to_str (event_lp->ptid));
+ }
+ else
+ {
+ /* No single-stepping LWP. Select one at random, out of those
+ which have had SIGTRAP events. */
+
+ /* First see how many SIGTRAP events we have. */
+ iterate_over_lwps (filter, count_events_callback, &num_events);
+
+ /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
+ random_selector = (int)
+ ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
+
+ if (debug_linux_nat && num_events > 1)
+ fprintf_unfiltered (gdb_stdlog,
+ "SEL: Found %d SIGTRAP events, selecting #%d\n",
+ num_events, random_selector);
+
+ event_lp = iterate_over_lwps (filter,
+ select_event_lwp_callback,
+ &random_selector);
+ }
+
+ if (event_lp != NULL)
+ {
+ /* Switch the event LWP. */
+ *orig_lp = event_lp;
+ *status = event_lp->status;
+ }
+
+ /* Flush the wait status for the event LWP. */
+ (*orig_lp)->status = 0;
+}
+
+/* Return non-zero if LP has been resumed. */
+
+static int
+resumed_callback (struct lwp_info *lp, void *data)
+{
+ return lp->resumed;
+}
+
+/* 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;
+}
+
+/* Check if we should go on and pass this event to common code.
+ Return the affected lwp if we are, or NULL otherwise. */
+static struct lwp_info *
+linux_nat_filter_event (int lwpid, int status, int options)
+{
+ struct lwp_info *lp;
+
+ lp = find_lwp_pid (pid_to_ptid (lwpid));
+
+ /* Check for stop events reported by a process we didn't already
+ know about - anything not already in our LWP list.
+
+ If we're expecting to receive stopped processes after
+ fork, vfork, and clone events, then we'll just add the
+ new one to our list and go back to waiting for the event
+ to be reported - the stopped process might be returned
+ from waitpid before or after the event is. */
+ if (WIFSTOPPED (status) && !lp)
+ {
+ linux_record_stopped_pid (lwpid, status);
+ return NULL;
+ }
+
+ /* Make sure we don't report an event for the exit of an LWP not in
+ our list, i.e. not part of the current process. This can happen
+ if we detach from a program we originally forked and then it
+ exits. */
+ if (!WIFSTOPPED (status) && !lp)
+ return NULL;
+
+ /* NOTE drow/2003-06-17: This code seems to be meant for debugging
+ CLONE_PTRACE processes which do not use the thread library -
+ otherwise we wouldn't find the new LWP this way. That doesn't
+ currently work, and the following code is currently unreachable
+ due to the two blocks above. If it's fixed some day, this code
+ should be broken out into a function so that we can also pick up
+ LWPs from the new interface. */
+ if (!lp)
+ {
+ lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
+ if (options & __WCLONE)
+ lp->cloned = 1;
+
+ gdb_assert (WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGSTOP);
+ lp->signalled = 1;
+
+ if (!in_thread_list (inferior_ptid))
+ {
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ add_thread (inferior_ptid);
+ }
+
+ add_thread (lp->ptid);
+ }
+
+ /* Handle GNU/Linux's syscall SIGTRAPs. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP)
+ {
+ /* No longer need the sysgood bit. The ptrace event ends up
+ recorded in lp->waitstatus if we care for it. We can carry
+ on handling the event like a regular SIGTRAP from here
+ on. */
+ status = W_STOPCODE (SIGTRAP);
+ if (linux_handle_syscall_trap (lp, 0))
+ return NULL;
+ }
+
+ /* 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;
+ }
+
+ if (linux_nat_status_is_event (status))
+ {
+ /* Save the trap's siginfo in case we need it later. */
+ save_siginfo (lp);
+
+ save_sigtrap (lp);
+ }
+
+ /* Check if the thread has exited. */
+ if ((WIFEXITED (status) || WIFSIGNALED (status))
+ && num_lwps (GET_PID (lp->ptid)) > 1)
+ {
+ /* If this is the main thread, we must stop all threads and verify
+ if they are still alive. This is because in the nptl thread model
+ on Linux 2.4, there is no signal issued for exiting LWPs
+ other than the main thread. We only get the main thread exit
+ signal once all child threads have already exited. If we
+ stop all the threads and use the stop_wait_callback to check
+ if they have exited we can determine whether this signal
+ should be ignored or whether it means the end of the debugged
+ application, regardless of which threading model is being
+ used. */
+ if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
+ {
+ lp->stopped = 1;
+ iterate_over_lwps (pid_to_ptid (GET_PID (lp->ptid)),
+ stop_and_resume_callback, NULL);
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ if (num_lwps (GET_PID (lp->ptid)) > 1)
+ {
+ /* If there is at least one more LWP, then the exit signal
+ was not the end of the debugged application and should be
+ ignored. */
+ exit_lwp (lp);
+ return NULL;
+ }
+ }
+
+ /* Check if the current LWP has previously exited. In the nptl
+ thread model, LWPs other than the main thread do not issue
+ signals when they exit so we must check whenever the thread has
+ stopped. A similar check is made in stop_wait_callback(). */
+ if (num_lwps (GET_PID (lp->ptid)) > 1 && !linux_thread_alive (lp->ptid))
+ {
+ ptid_t ptid = pid_to_ptid (GET_PID (lp->ptid));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
+
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (ptid, running_callback, NULL));
+
+ /* Discard the event. */
+ return NULL;
+ }
+
+ /* Make sure we don't report a SIGSTOP that we sent ourselves in
+ an attempt to stop an LWP. */
+ if (lp->signalled
+ && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Delayed SIGSTOP caught for %s.\n",
+ target_pid_to_str (lp->ptid));
+
+ /* This is a delayed SIGSTOP. */
+ lp->signalled = 0;
+
+ registers_changed ();
+
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
+ lp->step ?
+ "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid));
+
+ lp->stopped = 0;
+ gdb_assert (lp->resumed);
+
+ /* Discard the event. */
+ return NULL;
+ }
+
+ /* Make sure we don't report a SIGINT that we have already displayed
+ for another thread. */
+ if (lp->ignore_sigint
+ && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Delayed SIGINT caught for %s.\n",
+ target_pid_to_str (lp->ptid));
+
+ /* This is a delayed SIGINT. */
+ lp->ignore_sigint = 0;
+
+ registers_changed ();
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s %s, 0, 0 (discard SIGINT)\n",
+ lp->step ?
+ "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid));
+
+ lp->stopped = 0;
+ gdb_assert (lp->resumed);
+
+ /* Discard the event. */
+ return NULL;
+ }
+
+ /* An interesting event. */
+ gdb_assert (lp);
+ lp->status = status;
+ return lp;
+}
+
+static ptid_t
+linux_nat_wait_1 (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus,
+ int target_options)
+{
+ static sigset_t prev_mask;
+ struct lwp_info *lp = NULL;
+ int options = 0;
+ int status = 0;
+ pid_t pid;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LLW: enter\n");
+
+ /* The first time we get here after starting a new inferior, we may
+ not have added it to the LWP list yet - this is the earliest
+ moment at which we know its PID. */
+ if (ptid_is_pid (inferior_ptid))
+ {
+ /* Upgrade the main thread's ptid. */
+ thread_change_ptid (inferior_ptid,
+ BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid)));
+
+ lp = add_lwp (inferior_ptid);
+ lp->resumed = 1;
+ }
+
+ /* Make sure SIGCHLD is blocked. */
+ block_child_signals (&prev_mask);
+
+ if (ptid_equal (ptid, minus_one_ptid))
+ pid = -1;
+ else if (ptid_is_pid (ptid))
+ /* A request to wait for a specific tgid. This is not possible
+ with waitpid, so instead, we wait for any child, and leave
+ children we're not interested in right now with a pending
+ status to report later. */
+ pid = -1;
+ else
+ pid = GET_LWP (ptid);
+
+retry:
+ lp = NULL;
+ status = 0;
+
+ /* Make sure that of those LWPs we want to get an event from, there
+ is at least one LWP that has been resumed. If there's none, just
+ bail out. The core may just be flushing asynchronously all
+ events. */
+ if (iterate_over_lwps (ptid, resumed_callback, NULL) == NULL)
+ {
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n");
+
+ restore_child_signals_mask (&prev_mask);
+ return minus_one_ptid;
+ }
+
+ /* First check if there is a LWP with a wait status pending. */
+ if (pid == -1)
+ {
+ /* Any LWP that's been resumed will do. */
+ lp = iterate_over_lwps (ptid, status_callback, NULL);
+ if (lp)
+ {
+ if (debug_linux_nat && lp->status)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Using pending wait status %s for %s.\n",
+ status_to_str (lp->status),
+ target_pid_to_str (lp->ptid));
+ }
+
+ /* 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;
+ }
+ else if (is_lwp (ptid))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Waiting for specific LWP %s.\n",
+ target_pid_to_str (ptid));
+
+ /* We have a specific LWP to check. */
+ lp = find_lwp_pid (ptid);
+ gdb_assert (lp);
+
+ if (debug_linux_nat && lp->status)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Using pending wait status %s for %s.\n",
+ status_to_str (lp->status),
+ target_pid_to_str (lp->ptid));
+
+ /* If we have to wait, take into account whether PID is a cloned
+ process or not. And we have to convert it to something that
+ the layer beneath us can understand. */
+ options = lp->cloned ? __WCLONE : 0;
+ pid = GET_LWP (ptid);
+
+ /* We check for lp->waitstatus in addition to lp->status,
+ because we can have pending process exits recorded in
+ lp->status and W_EXITCODE(0,0) == 0. We should probably have
+ an additional lp->status_p flag. */
+ if (lp->status == 0 && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE)
+ lp = NULL;
+ }
+
+ if (lp && lp->signalled)
+ {
+ /* A pending SIGSTOP may interfere with the normal stream of
+ events. In a typical case where interference is a problem,
+ we have a SIGSTOP signal pending for LWP A while
+ single-stepping it, encounter an event in LWP B, and take the
+ pending SIGSTOP while trying to stop LWP A. After processing
+ the event in LWP B, LWP A is continued, and we'll never see
+ the SIGTRAP associated with the last time we were
+ single-stepping LWP A. */
+
+ /* Resume the thread. It should halt immediately returning the
+ pending SIGSTOP. */
+ registers_changed ();
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s %s, 0, 0 (expect SIGSTOP)\n",
+ lp->step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid));
+ lp->stopped = 0;
+ gdb_assert (lp->resumed);
+
+ /* Catch the pending SIGSTOP. */
+ status = lp->status;
+ lp->status = 0;
+
+ stop_wait_callback (lp, NULL);
+
+ /* If the lp->status field isn't empty, we caught another signal
+ while flushing the SIGSTOP. Return it back to the event
+ queue of the LWP, as we already have an event to handle. */
+ if (lp->status)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: kill %s, %s\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str (lp->status));
+ kill_lwp (GET_LWP (lp->ptid), WSTOPSIG (lp->status));
+ }
+
+ lp->status = status;
+ }
+
+ if (!target_can_async_p ())
+ {
+ /* Causes SIGINT to be passed on to the attached process. */
+ set_sigint_trap ();
+ }
+
+ /* Translate generic target_wait options into waitpid options. */
+ if (target_options & TARGET_WNOHANG)
+ options |= WNOHANG;
+
+ while (lp == NULL)
+ {
+ pid_t lwpid;
+
+ lwpid = my_waitpid (pid, &status, options);
+
+ if (lwpid > 0)
+ {
+ gdb_assert (pid == -1 || lwpid == pid);
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: waitpid %ld received %s\n",
+ (long) lwpid, status_to_str (status));
+ }
+
+ lp = linux_nat_filter_event (lwpid, status, options);
+
+ /* STATUS is now no longer valid, use LP->STATUS instead. */
+ status = 0;
+
+ if (lp
+ && ptid_is_pid (ptid)
+ && ptid_get_pid (lp->ptid) != ptid_get_pid (ptid))
+ {
+ gdb_assert (lp->resumed);
+
+ if (debug_linux_nat)
+ fprintf (stderr,
+ "LWP %ld got an event %06x, leaving pending.\n",
+ ptid_get_lwp (lp->ptid), lp->status);
+
+ if (WIFSTOPPED (lp->status))
+ {
+ if (WSTOPSIG (lp->status) != SIGSTOP)
+ {
+ /* Cancel breakpoint hits. The breakpoint may
+ be removed before we fetch events from this
+ process to report to the core. It is best
+ not to assume the moribund breakpoints
+ heuristic always handles these cases --- it
+ could be too many events go through to the
+ core before this one is handled. All-stop
+ always cancels breakpoint hits in all
+ threads. */
+ if (non_stop
+ && linux_nat_lp_status_is_event (lp)
+ && cancel_breakpoint (lp))
+ {
+ /* Throw away the SIGTRAP. */
+ lp->status = 0;
+
+ if (debug_linux_nat)
+ fprintf (stderr,
+ "LLW: LWP %ld hit a breakpoint while"
+ " waiting for another process;"
+ " cancelled it\n",
+ ptid_get_lwp (lp->ptid));
+ }
+ lp->stopped = 1;
+ }
+ else
+ {
+ lp->stopped = 1;
+ lp->signalled = 0;
+ }
+ }
+ else if (WIFEXITED (lp->status) || WIFSIGNALED (lp->status))
+ {
+ if (debug_linux_nat)
+ fprintf (stderr,
+ "Process %ld exited while stopping LWPs\n",
+ ptid_get_lwp (lp->ptid));
+
+ /* This was the last lwp in the process. Since
+ events are serialized to GDB core, and we can't
+ report this one right now, but GDB core and the
+ other target layers will want to be notified
+ about the exit code/signal, leave the status
+ pending for the next time we're able to report
+ it. */
+
+ /* Prevent trying to stop this thread again. We'll
+ never try to resume it because it has a pending
+ status. */
+ lp->stopped = 1;
+
+ /* Dead LWP's aren't expected to reported a pending
+ sigstop. */
+ lp->signalled = 0;
+
+ /* Store the pending event in the waitstatus as
+ well, because W_EXITCODE(0,0) == 0. */
+ store_waitstatus (&lp->waitstatus, lp->status);
+ }
+
+ /* Keep looking. */
+ lp = NULL;
+ continue;
+ }
+
+ if (lp)
+ break;
+ else
+ {
+ if (pid == -1)
+ {
+ /* waitpid did return something. Restart over. */
+ options |= __WCLONE;
+ }
+ continue;
+ }
+ }
+
+ if (pid == -1)
+ {
+ /* Alternate between checking cloned and uncloned processes. */
+ options ^= __WCLONE;
+
+ /* And every time we have checked both:
+ In async mode, return to event loop;
+ In sync mode, suspend waiting for a SIGCHLD signal. */
+ if (options & __WCLONE)
+ {
+ if (target_options & TARGET_WNOHANG)
+ {
+ /* No interesting event. */
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
+
+ restore_child_signals_mask (&prev_mask);
+ return minus_one_ptid;
+ }
+
+ sigsuspend (&suspend_mask);
+ }
+ }
+ else if (target_options & TARGET_WNOHANG)
+ {
+ /* No interesting event for PID yet. */
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n");
+
+ restore_child_signals_mask (&prev_mask);
+ return minus_one_ptid;
+ }
+
+ /* We shouldn't end up here unless we want to try again. */
+ gdb_assert (lp == NULL);
+ }
+
+ if (!target_can_async_p ())
+ clear_sigint_trap ();
+
+ gdb_assert (lp);
+
+ status = lp->status;
+ lp->status = 0;
+
+ /* Don't report signals that GDB isn't interested in, such as
+ signals that are neither printed nor stopped upon. Stopping all
+ threads can be a bit time-consuming so if we want decent
+ performance with heavily multi-threaded programs, especially when
+ they're using a high frequency timer, we'd better avoid it if we
+ can. */
+
+ if (WIFSTOPPED (status))
+ {
+ enum target_signal signo = target_signal_from_host (WSTOPSIG (status));
+
+ /* When using hardware single-step, we need to report every signal.
+ Otherwise, signals in pass_mask may be short-circuited. */
+ if (!lp->step
+ && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)))
+ {
+ /* FIMXE: kettenis/2001-06-06: Should we resume all threads
+ here? It is not clear we should. GDB may not expect
+ other threads to run. On the other hand, not resuming
+ newly attached threads may cause an unwanted delay in
+ getting them running. */
+ registers_changed ();
+ linux_ops->to_resume (linux_ops, 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",
+ lp->step ?
+ "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid),
+ (signo != TARGET_SIGNAL_0
+ ? strsignal (target_signal_to_host (signo))
+ : "0"));
+ lp->stopped = 0;
+ goto retry;
+ }
+
+ if (!non_stop)
+ {
+ /* Only do the below in all-stop, as we currently use SIGINT
+ to implement target_stop (see linux_nat_stop) in
+ non-stop. */
+ if (signo == TARGET_SIGNAL_INT && signal_pass_state (signo) == 0)
+ {
+ /* If ^C/BREAK is typed at the tty/console, SIGINT gets
+ forwarded to the entire process group, that is, all LWPs
+ will receive it - unless they're using CLONE_THREAD to
+ share signals. Since we only want to report it once, we
+ mark it as ignored for all LWPs except this one. */
+ iterate_over_lwps (pid_to_ptid (ptid_get_pid (ptid)),
+ set_ignore_sigint, NULL);
+ lp->ignore_sigint = 0;
+ }
+ else
+ maybe_clear_ignore_sigint (lp);
+ }
+ }
+
+ /* This LWP is stopped now. */
+ lp->stopped = 1;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LLW: Candidate event %s in %s.\n",
+ status_to_str (status), target_pid_to_str (lp->ptid));
+
+ if (!non_stop)
+ {
+ /* Now stop all other LWP's ... */
+ iterate_over_lwps (minus_one_ptid, stop_callback, NULL);
+
+ /* ... and wait until all of them have reported back that
+ they're no longer running. */
+ iterate_over_lwps (minus_one_ptid, stop_wait_callback, NULL);
+
+ /* If we're not waiting for a specific LWP, choose an event LWP
+ from among those that have had events. Giving equal priority
+ to all LWPs that have had events helps prevent
+ starvation. */
+ if (pid == -1)
+ select_event_lwp (ptid, &lp, &status);
+
+ /* Now that we've selected our final event LWP, cancel any
+ breakpoints in other LWPs that have hit a GDB breakpoint.
+ See the comment in cancel_breakpoints_callback to find out
+ why. */
+ iterate_over_lwps (minus_one_ptid, cancel_breakpoints_callback, lp);
+
+ /* In all-stop, from the core's perspective, all LWPs are now
+ stopped until a new resume action is sent over. */
+ iterate_over_lwps (minus_one_ptid, resume_clear_callback, NULL);
+ }
+ else
+ lp->resumed = 0;
+
+ if (linux_nat_status_is_event (status))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: trap ptid is %s.\n",
+ target_pid_to_str (lp->ptid));
+ }
+
+ if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
+ {
+ *ourstatus = lp->waitstatus;
+ lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+ }
+ else
+ store_waitstatus (ourstatus, status);
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog, "LLW: exit\n");
+
+ restore_child_signals_mask (&prev_mask);
+
+ if (ourstatus->kind == TARGET_WAITKIND_EXITED
+ || ourstatus->kind == TARGET_WAITKIND_SIGNALLED)
+ lp->core = -1;
+ else
+ lp->core = linux_nat_core_of_thread_1 (lp->ptid);
+
+ return lp->ptid;
+}
+
+/* Resume LWPs that are currently stopped without any pending status
+ to report, but are resumed from the core's perspective. */
+
+static int
+resume_stopped_resumed_lwps (struct lwp_info *lp, void *data)
+{
+ ptid_t *wait_ptid_p = data;
+
+ if (lp->stopped
+ && lp->resumed
+ && lp->status == 0
+ && lp->waitstatus.kind == TARGET_WAITKIND_IGNORE)
+ {
+ gdb_assert (is_executing (lp->ptid));
+
+ /* Don't bother if there's a breakpoint at PC that we'd hit
+ immediately, and we're not waiting for this LWP. */
+ if (!ptid_match (lp->ptid, *wait_ptid_p))
+ {
+ struct regcache *regcache = get_thread_regcache (lp->ptid);
+ CORE_ADDR pc = regcache_read_pc (regcache);
+
+ if (breakpoint_inserted_here_p (get_regcache_aspace (regcache), pc))
+ return 0;
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "RSRL: resuming stopped-resumed LWP %s\n",
+ target_pid_to_str (lp->ptid));
+
+ linux_ops->to_resume (linux_ops, pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ lp->stopped = 0;
+ memset (&lp->siginfo, 0, sizeof (lp->siginfo));
+ lp->stopped_by_watchpoint = 0;
+ }
+
+ return 0;
+}
+
+static ptid_t
+linux_nat_wait (struct target_ops *ops,
+ ptid_t ptid, struct target_waitstatus *ourstatus,
+ int target_options)
+{
+ ptid_t event_ptid;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "linux_nat_wait: [%s]\n", target_pid_to_str (ptid));
+
+ /* Flush the async file first. */
+ if (target_can_async_p ())
+ async_file_flush ();
+
+ /* Resume LWPs that are currently stopped without any pending status
+ to report, but are resumed from the core's perspective. LWPs get
+ in this state if we find them stopping at a time we're not
+ interested in reporting the event (target_wait on a
+ specific_process, for example, see linux_nat_wait_1), and
+ meanwhile the event became uninteresting. Don't bother resuming
+ LWPs we're not going to wait for if they'd stop immediately. */
+ if (non_stop)
+ iterate_over_lwps (minus_one_ptid, resume_stopped_resumed_lwps, &ptid);
+
+ event_ptid = linux_nat_wait_1 (ops, ptid, ourstatus, target_options);
+
+ /* If we requested any event, and something came out, assume there
+ may be more. If we requested a specific lwp or process, also
+ assume there may be more. */
+ if (target_can_async_p ()
+ && (ourstatus->kind != TARGET_WAITKIND_IGNORE
+ || !ptid_equal (ptid, minus_one_ptid)))
+ async_file_mark ();
+
+ /* Get ready for the next event. */
+ if (target_can_async_p ())
+ target_async (inferior_event_handler, 0);
+
+ return event_ptid;
+}
+
+static int
+kill_callback (struct lwp_info *lp, void *data)
+{
+ /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */
+
+ errno = 0;
+ kill (GET_LWP (lp->ptid), SIGKILL);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "KC: kill (SIGKILL) %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ /* Some kernels ignore even SIGKILL for processes under ptrace. */
+
+ errno = 0;
+ ptrace (PTRACE_KILL, GET_LWP (lp->ptid), 0, 0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "KC: PTRACE_KILL %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ return 0;
+}
+
+static int
+kill_wait_callback (struct lwp_info *lp, void *data)
+{
+ pid_t pid;
+
+ /* We must make sure that there are no pending events (delayed
+ SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current
+ program doesn't interfere with any following debugging session. */
+
+ /* For cloned processes we must check both with __WCLONE and
+ without, since the exit status of a cloned process isn't reported
+ with __WCLONE. */
+ if (lp->cloned)
+ {
+ do
+ {
+ pid = my_waitpid (GET_LWP (lp->ptid), NULL, __WCLONE);
+ if (pid != (pid_t) -1)
+ {
+ 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));
+
+ gdb_assert (pid == -1 && errno == ECHILD);
+ }
+
+ do
+ {
+ pid = my_waitpid (GET_LWP (lp->ptid), NULL, 0);
+ if (pid != (pid_t) -1)
+ {
+ 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));
+
+ gdb_assert (pid == -1 && errno == ECHILD);
+ return 0;
+}
+
+static void
+linux_nat_kill (struct target_ops *ops)
+{
+ struct target_waitstatus last;
+ ptid_t last_ptid;
+ int status;
+
+ /* 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)
+ if (last.kind == TARGET_WAITKIND_FORKED
+ || last.kind == TARGET_WAITKIND_VFORKED)
+ {
+ ptrace (PT_KILL, PIDGET (last.value.related_pid), 0, 0);
+ wait (&status);
+ }
+
+ if (forks_exist_p ())
+ linux_fork_killall ();
+ else
+ {
+ ptid_t ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+
+ /* Stop all threads before killing them, since ptrace requires
+ that the thread is stopped to sucessfully PTRACE_KILL. */
+ iterate_over_lwps (ptid, stop_callback, NULL);
+ /* ... and wait until all of them have reported back that
+ they're no longer running. */
+ iterate_over_lwps (ptid, stop_wait_callback, NULL);
+
+ /* Kill all LWP's ... */
+ iterate_over_lwps (ptid, kill_callback, NULL);
+
+ /* ... and wait until we've flushed all events. */
+ iterate_over_lwps (ptid, kill_wait_callback, NULL);
+ }
+
+ target_mourn_inferior ();
+}
+
+static void
+linux_nat_mourn_inferior (struct target_ops *ops)
+{
+ purge_lwp_list (ptid_get_pid (inferior_ptid));
+
+ if (! forks_exist_p ())
+ /* Normal case, no other forks available. */
+ linux_ops->to_mourn_inferior (ops);
+ else
+ /* Multi-fork case. The current inferior_ptid has exited, but
+ there are other viable forks to debug. Delete the exiting
+ one and context-switch to the first available. */
+ linux_fork_mourn_inferior ();
+}
+
+/* Convert a native/host siginfo object, into/from the siginfo in the
+ layout of the inferiors' architecture. */
+
+static void
+siginfo_fixup (struct siginfo *siginfo, gdb_byte *inf_siginfo, int direction)
+{
+ int done = 0;
+
+ if (linux_nat_siginfo_fixup != NULL)
+ done = linux_nat_siginfo_fixup (siginfo, inf_siginfo, direction);
+
+ /* If there was no callback, or the callback didn't do anything,
+ then just do a straight memcpy. */
+ if (!done)
+ {
+ if (direction == 1)
+ memcpy (siginfo, inf_siginfo, sizeof (struct siginfo));
+ else
+ memcpy (inf_siginfo, siginfo, sizeof (struct siginfo));
+ }
+}
+
+static LONGEST
+linux_xfer_siginfo (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
+{
+ int pid;
+ struct siginfo siginfo;
+ gdb_byte inf_siginfo[sizeof (struct siginfo)];
+
+ gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO);
+ gdb_assert (readbuf || writebuf);
+
+ pid = GET_LWP (inferior_ptid);
+ if (pid == 0)
+ pid = GET_PID (inferior_ptid);
+
+ if (offset > sizeof (siginfo))
+ return -1;
+
+ errno = 0;
+ ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo);
+ if (errno != 0)
+ return -1;
+
+ /* When GDB is built as a 64-bit application, ptrace writes into
+ SIGINFO an object with 64-bit layout. Since debugging a 32-bit
+ inferior with a 64-bit GDB should look the same as debugging it
+ with a 32-bit GDB, we need to convert it. GDB core always sees
+ the converted layout, so any read/write will have to be done
+ post-conversion. */
+ siginfo_fixup (&siginfo, inf_siginfo, 0);
+
+ if (offset + len > sizeof (siginfo))
+ len = sizeof (siginfo) - offset;
+
+ if (readbuf != NULL)
+ memcpy (readbuf, inf_siginfo + offset, len);
+ else
+ {
+ memcpy (inf_siginfo + offset, writebuf, len);
+
+ /* Convert back to ptrace layout before flushing it out. */
+ siginfo_fixup (&siginfo, inf_siginfo, 1);
+
+ errno = 0;
+ ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo);
+ if (errno != 0)
+ return -1;
+ }
+
+ return len;
+}
+
+static LONGEST
+linux_nat_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, LONGEST len)
+{
+ struct cleanup *old_chain;
+ LONGEST xfer;
+
+ if (object == TARGET_OBJECT_SIGNAL_INFO)
+ return linux_xfer_siginfo (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
+ /* The target is connected but no live inferior is selected. Pass
+ this request down to a lower stratum (e.g., the executable
+ file). */
+ if (object == TARGET_OBJECT_MEMORY && ptid_equal (inferior_ptid, null_ptid))
+ return 0;
+
+ old_chain = save_inferior_ptid ();
+
+ if (is_lwp (inferior_ptid))
+ inferior_ptid = pid_to_ptid (GET_LWP (inferior_ptid));
+
+ xfer = linux_ops->to_xfer_partial (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
+ do_cleanups (old_chain);
+ return xfer;
+}
+
+static int
+linux_thread_alive (ptid_t ptid)
+{
+ int err, tmp_errno;
+
+ gdb_assert (is_lwp (ptid));
+
+ /* Send signal 0 instead of anything ptrace, because ptracing a
+ running thread errors out claiming that the thread doesn't
+ exist. */
+ err = kill_lwp (GET_LWP (ptid), 0);
+ tmp_errno = errno;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLTA: KILL(SIG0) %s (%s)\n",
+ target_pid_to_str (ptid),
+ err ? safe_strerror (tmp_errno) : "OK");
+
+ if (err != 0)
+ return 0;
+
+ return 1;
+}
+
+static int
+linux_nat_thread_alive (struct target_ops *ops, ptid_t ptid)
+{
+ return linux_thread_alive (ptid);
+}
+
+static char *
+linux_nat_pid_to_str (struct target_ops *ops, ptid_t ptid)
+{
+ static char buf[64];
+
+ if (is_lwp (ptid)
+ && (GET_PID (ptid) != GET_LWP (ptid)
+ || num_lwps (GET_PID (ptid)) > 1))
+ {
+ snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid));
+ return buf;
+ }
+
+ return normal_pid_to_str (ptid);
+}
+
+static char *
+linux_nat_thread_name (struct thread_info *thr)
+{
+ int pid = ptid_get_pid (thr->ptid);
+ long lwp = ptid_get_lwp (thr->ptid);
+#define FORMAT "/proc/%d/task/%ld/comm"
+ char buf[sizeof (FORMAT) + 30];
+ FILE *comm_file;
+ char *result = NULL;
+
+ snprintf (buf, sizeof (buf), FORMAT, pid, lwp);
+ comm_file = fopen (buf, "r");
+ if (comm_file)
+ {
+ /* Not exported by the kernel, so we define it here. */
+#define COMM_LEN 16
+ static char line[COMM_LEN + 1];
+
+ if (fgets (line, sizeof (line), comm_file))
+ {
+ char *nl = strchr (line, '\n');
+
+ if (nl)
+ *nl = '\0';
+ if (*line != '\0')
+ result = line;
+ }
+
+ fclose (comm_file);
+ }
+
+#undef COMM_LEN
+#undef FORMAT
+
+ return result;
+}
+
+/* Accepts an integer PID; Returns a string representing a file that
+ can be opened to get the symbols for the child process. */
+
+static char *
+linux_child_pid_to_exec_file (int pid)
+{
+ char *name1, *name2;
+
+ name1 = xmalloc (MAXPATHLEN);
+ name2 = xmalloc (MAXPATHLEN);
+ make_cleanup (xfree, name1);
+ make_cleanup (xfree, name2);
+ memset (name2, 0, MAXPATHLEN);
+
+ sprintf (name1, "/proc/%d/exe", pid);
+ if (readlink (name1, name2, MAXPATHLEN) > 0)
+ return name2;
+ else
+ return name1;
+}
+
+/* Service function for corefiles and info proc. */
+
+static int
+read_mapping (FILE *mapfile,
+ long long *addr,
+ long long *endaddr,
+ char *permissions,
+ long long *offset,
+ char *device, long long *inode, char *filename)
+{
+ int ret = fscanf (mapfile, "%llx-%llx %s %llx %s %llx",
+ addr, endaddr, permissions, offset, device, inode);
+
+ 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
+ confusing this code. It also makes this code more robust in
+ respect to annotations the kernel may add after the filename.
+
+ Note the filename is used for informational purposes
+ only. */
+ ret += fscanf (mapfile, "%[^\n]\n", filename);
+ }
+
+ return (ret != 0 && ret != EOF);
+}
+
+/* Fills the "to_find_memory_regions" target vector. Lists the memory
+ regions in the inferior for a corefile. */
+
+static int
+linux_nat_find_memory_regions (find_memory_region_ftype func, void *obfd)
+{
+ int pid = PIDGET (inferior_ptid);
+ char mapsfilename[MAXPATHLEN];
+ FILE *mapsfile;
+ long long addr, endaddr, size, offset, inode;
+ char permissions[8], device[8], filename[MAXPATHLEN];
+ int read, write, exec;
+ struct cleanup *cleanup;
+
+ /* Compose the filename for the /proc memory map, and open it. */
+ sprintf (mapsfilename, "/proc/%d/maps", pid);
+ if ((mapsfile = fopen (mapsfilename, "r")) == NULL)
+ error (_("Could not open %s."), mapsfilename);
+ cleanup = make_cleanup_fclose (mapsfile);
+
+ if (info_verbose)
+ fprintf_filtered (gdb_stdout,
+ "Reading memory regions from %s\n", mapsfilename);
+
+ /* Now iterate until end-of-file. */
+ while (read_mapping (mapsfile, &addr, &endaddr, &permissions[0],
+ &offset, &device[0], &inode, &filename[0]))
+ {
+ size = endaddr - addr;
+
+ /* Get the segment's permissions. */
+ read = (strchr (permissions, 'r') != 0);
+ write = (strchr (permissions, 'w') != 0);
+ exec = (strchr (permissions, 'x') != 0);
+
+ if (info_verbose)
+ {
+ fprintf_filtered (gdb_stdout,
+ "Save segment, %s bytes at %s (%c%c%c)",
+ plongest (size), paddress (target_gdbarch, addr),
+ read ? 'r' : ' ',
+ write ? 'w' : ' ', exec ? 'x' : ' ');
+ if (filename[0])
+ fprintf_filtered (gdb_stdout, " for %s", filename);
+ fprintf_filtered (gdb_stdout, "\n");
+ }
+
+ /* Invoke the callback function to create the corefile
+ segment. */
+ func (addr, size, read, write, exec, obfd);
+ }
+ do_cleanups (cleanup);
+ return 0;
+}
+
+static int
+find_signalled_thread (struct thread_info *info, void *data)
+{
+ if (info->suspend.stop_signal != TARGET_SIGNAL_0
+ && ptid_get_pid (info->ptid) == ptid_get_pid (inferior_ptid))
+ return 1;
+
+ return 0;
+}
+
+static enum target_signal
+find_stop_signal (void)
+{
+ struct thread_info *info =
+ iterate_over_threads (find_signalled_thread, NULL);
+
+ if (info)
+ return info->suspend.stop_signal;
+ else
+ return TARGET_SIGNAL_0;
+}
+
+/* Records the thread's register state for the corefile note
+ section. */
+
+static char *
+linux_nat_do_thread_registers (bfd *obfd, ptid_t ptid,
+ char *note_data, int *note_size,
+ enum target_signal stop_signal)
+{
+ unsigned long lwp = ptid_get_lwp (ptid);
+ struct gdbarch *gdbarch = target_gdbarch;
+ struct regcache *regcache = get_thread_arch_regcache (ptid, gdbarch);
+ const struct regset *regset;
+ int core_regset_p;
+ struct cleanup *old_chain;
+ struct core_regset_section *sect_list;
+ char *gdb_regset;
+
+ old_chain = save_inferior_ptid ();
+ inferior_ptid = ptid;
+ target_fetch_registers (regcache, -1);
+ do_cleanups (old_chain);
+
+ core_regset_p = gdbarch_regset_from_core_section_p (gdbarch);
+ sect_list = gdbarch_core_regset_sections (gdbarch);
+
+ /* The loop below uses the new struct core_regset_section, which stores
+ the supported section names and sizes for the core file. Note that
+ note PRSTATUS needs to be treated specially. But the other notes are
+ structurally the same, so they can benefit from the new struct. */
+ if (core_regset_p && sect_list != NULL)
+ while (sect_list->sect_name != NULL)
+ {
+ regset = gdbarch_regset_from_core_section (gdbarch,
+ sect_list->sect_name,
+ sect_list->size);
+ gdb_assert (regset && regset->collect_regset);
+ gdb_regset = xmalloc (sect_list->size);
+ regset->collect_regset (regset, regcache, -1,
+ gdb_regset, sect_list->size);
+
+ if (strcmp (sect_list->sect_name, ".reg") == 0)
+ note_data = (char *) elfcore_write_prstatus
+ (obfd, note_data, note_size,
+ lwp, target_signal_to_host (stop_signal),
+ gdb_regset);
+ else
+ note_data = (char *) elfcore_write_register_note
+ (obfd, note_data, note_size,
+ sect_list->sect_name, gdb_regset,
+ sect_list->size);
+ xfree (gdb_regset);
+ sect_list++;
+ }
+
+ /* For architectures that does not have the struct core_regset_section
+ implemented, we use the old method. When all the architectures have
+ the new support, the code below should be deleted. */
+ else
+ {
+ gdb_gregset_t gregs;
+ gdb_fpregset_t fpregs;
+
+ 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);
+
+ note_data = (char *) elfcore_write_prstatus
+ (obfd, note_data, note_size, lwp, target_signal_to_host (stop_signal),
+ &gregs);
+
+ if (core_regset_p
+ && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2",
+ sizeof (fpregs)))
+ != NULL && regset->collect_regset != NULL)
+ regset->collect_regset (regset, regcache, -1,
+ &fpregs, sizeof (fpregs));
+ else
+ fill_fpregset (regcache, &fpregs, -1);
+
+ note_data = (char *) elfcore_write_prfpreg (obfd,
+ note_data,
+ note_size,
+ &fpregs, sizeof (fpregs));
+ }
+
+ return note_data;
+}
+
+struct linux_nat_corefile_thread_data
+{
+ bfd *obfd;
+ char *note_data;
+ int *note_size;
+ int num_notes;
+ enum target_signal stop_signal;
+};
+
+/* Called by gdbthread.c once per thread. Records the thread's
+ register state for the corefile note section. */
+
+static int
+linux_nat_corefile_thread_callback (struct lwp_info *ti, void *data)
+{
+ struct linux_nat_corefile_thread_data *args = data;
+
+ args->note_data = linux_nat_do_thread_registers (args->obfd,
+ ti->ptid,
+ args->note_data,
+ args->note_size,
+ args->stop_signal);
+ args->num_notes++;
+
+ return 0;
+}
+
+/* Enumerate spufs IDs for process PID. */
+
+static void
+iterate_over_spus (int pid, void (*callback) (void *, int), void *data)
+{
+ char path[128];
+ DIR *dir;
+ struct dirent *entry;
+
+ xsnprintf (path, sizeof path, "/proc/%d/fd", pid);
+ dir = opendir (path);
+ if (!dir)
+ return;
+
+ rewinddir (dir);
+ while ((entry = readdir (dir)) != NULL)
+ {
+ struct stat st;
+ struct statfs stfs;
+ int fd;
+
+ fd = atoi (entry->d_name);
+ if (!fd)
+ continue;
+
+ xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd);
+ if (stat (path, &st) != 0)
+ continue;
+ if (!S_ISDIR (st.st_mode))
+ continue;
+
+ if (statfs (path, &stfs) != 0)
+ continue;
+ if (stfs.f_type != SPUFS_MAGIC)
+ continue;
+
+ callback (data, fd);
+ }
+
+ closedir (dir);
+}
+
+/* Generate corefile notes for SPU contexts. */
+
+struct linux_spu_corefile_data
+{
+ bfd *obfd;
+ char *note_data;
+ int *note_size;
+};
+
+static void
+linux_spu_corefile_callback (void *data, int fd)
+{
+ struct linux_spu_corefile_data *args = data;
+ int i;
+
+ static const char *spu_files[] =
+ {
+ "object-id",
+ "mem",
+ "regs",
+ "fpcr",
+ "lslr",
+ "decr",
+ "decr_status",
+ "signal1",
+ "signal1_type",
+ "signal2",
+ "signal2_type",
+ "event_mask",
+ "event_status",
+ "mbox_info",
+ "ibox_info",
+ "wbox_info",
+ "dma_info",
+ "proxydma_info",
+ };
+
+ for (i = 0; i < sizeof (spu_files) / sizeof (spu_files[0]); i++)
+ {
+ char annex[32], note_name[32];
+ gdb_byte *spu_data;
+ LONGEST spu_len;
+
+ xsnprintf (annex, sizeof annex, "%d/%s", fd, spu_files[i]);
+ spu_len = target_read_alloc (¤t_target, TARGET_OBJECT_SPU,
+ annex, &spu_data);
+ if (spu_len > 0)
+ {
+ xsnprintf (note_name, sizeof note_name, "SPU/%s", annex);
+ args->note_data = elfcore_write_note (args->obfd, args->note_data,
+ args->note_size, note_name,
+ NT_SPU, spu_data, spu_len);
+ xfree (spu_data);
+ }
+ }
+}
+
+static char *
+linux_spu_make_corefile_notes (bfd *obfd, char *note_data, int *note_size)
+{
+ struct linux_spu_corefile_data args;
+
+ args.obfd = obfd;
+ args.note_data = note_data;
+ args.note_size = note_size;
+
+ iterate_over_spus (PIDGET (inferior_ptid),
+ linux_spu_corefile_callback, &args);
+
+ return args.note_data;
+}
+
+/* Fills the "to_make_corefile_note" target vector. Builds the note
+ section for a corefile, and returns it in a malloc buffer. */
+
+static char *
+linux_nat_make_corefile_notes (bfd *obfd, int *note_size)
+{
+ struct linux_nat_corefile_thread_data thread_args;
+ /* 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 filter = pid_to_ptid (ptid_get_pid (inferior_ptid));
+ gdb_byte *auxv;
+ int auxv_len;
+
+ if (get_exec_file (0))
+ {
+ strncpy (fname, lbasename (get_exec_file (0)), sizeof (fname));
+ strncpy (psargs, get_exec_file (0), sizeof (psargs));
+ if (get_inferior_args ())
+ {
+ 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,
+ note_size, fname, psargs);
+ }
+
+ /* Dump information for threads. */
+ thread_args.obfd = obfd;
+ thread_args.note_data = note_data;
+ thread_args.note_size = note_size;
+ thread_args.num_notes = 0;
+ thread_args.stop_signal = find_stop_signal ();
+ iterate_over_lwps (filter, linux_nat_corefile_thread_callback, &thread_args);
+ gdb_assert (thread_args.num_notes != 0);
+ note_data = thread_args.note_data;
+
+ auxv_len = target_read_alloc (¤t_target, TARGET_OBJECT_AUXV,
+ NULL, &auxv);
+ if (auxv_len > 0)
+ {
+ note_data = elfcore_write_note (obfd, note_data, note_size,
+ "CORE", NT_AUXV, auxv, auxv_len);
+ xfree (auxv);
+ }
+
+ note_data = linux_spu_make_corefile_notes (obfd, note_data, note_size);
+
+ make_cleanup (xfree, note_data);
+ return note_data;
+}
+
+/* Implement the "info proc" command. */
+
+static void
+linux_nat_info_proc_cmd (char *args, int from_tty)
+{
+ /* A long is used for pid instead of an int to avoid a loss of precision
+ compiler warning from the output of strtoul. */
+ long pid = PIDGET (inferior_ptid);
+ FILE *procfile;
+ char **argv = NULL;
+ char buffer[MAXPATHLEN];
+ char fname1[MAXPATHLEN], fname2[MAXPATHLEN];
+ int cmdline_f = 1;
+ int cwd_f = 1;
+ int exe_f = 1;
+ int mappings_f = 0;
+ int status_f = 0;
+ int stat_f = 0;
+ int all = 0;
+ struct stat dummy;
+
+ if (args)
+ {
+ /* Break up 'args' into an argv array. */
+ argv = gdb_buildargv (args);
+ make_cleanup_freeargv (argv);
+ }
+ while (argv != NULL && *argv != NULL)
+ {
+ if (isdigit (argv[0][0]))
+ {
+ pid = strtoul (argv[0], NULL, 10);
+ }
+ else if (strncmp (argv[0], "mappings", strlen (argv[0])) == 0)
+ {
+ mappings_f = 1;
+ }
+ else if (strcmp (argv[0], "status") == 0)
+ {
+ status_f = 1;
+ }
+ else if (strcmp (argv[0], "stat") == 0)
+ {
+ stat_f = 1;
+ }
+ else if (strcmp (argv[0], "cmd") == 0)
+ {
+ cmdline_f = 1;
+ }
+ else if (strncmp (argv[0], "exe", strlen (argv[0])) == 0)
+ {
+ exe_f = 1;
+ }
+ else if (strcmp (argv[0], "cwd") == 0)
+ {
+ cwd_f = 1;
+ }
+ else if (strncmp (argv[0], "all", strlen (argv[0])) == 0)
+ {
+ all = 1;
+ }
+ else
+ {
+ /* [...] (future options here). */
+ }
+ argv++;
+ }
+ if (pid == 0)
+ error (_("No current process: you must name one."));
+
+ sprintf (fname1, "/proc/%ld", pid);
+ if (stat (fname1, &dummy) != 0)
+ error (_("No /proc directory: '%s'"), fname1);
+
+ printf_filtered (_("process %ld\n"), pid);
+ if (cmdline_f || all)
+ {
+ sprintf (fname1, "/proc/%ld/cmdline", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
+
+ if (fgets (buffer, sizeof (buffer), procfile))
+ printf_filtered ("cmdline = '%s'\n", buffer);
+ else
+ warning (_("unable to read '%s'"), fname1);
+ do_cleanups (cleanup);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+ if (cwd_f || all)
+ {
+ sprintf (fname1, "/proc/%ld/cwd", pid);
+ memset (fname2, 0, sizeof (fname2));
+ if (readlink (fname1, fname2, sizeof (fname2)) > 0)
+ printf_filtered ("cwd = '%s'\n", fname2);
+ else
+ warning (_("unable to read link '%s'"), fname1);
+ }
+ if (exe_f || all)
+ {
+ sprintf (fname1, "/proc/%ld/exe", pid);
+ memset (fname2, 0, sizeof (fname2));
+ if (readlink (fname1, fname2, sizeof (fname2)) > 0)
+ printf_filtered ("exe = '%s'\n", fname2);
+ else
+ warning (_("unable to read link '%s'"), fname1);
+ }
+ if (mappings_f || all)
+ {
+ sprintf (fname1, "/proc/%ld/maps", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ long long addr, endaddr, size, offset, inode;
+ char permissions[8], device[8], filename[MAXPATHLEN];
+ struct cleanup *cleanup;
+
+ cleanup = make_cleanup_fclose (procfile);
+ printf_filtered (_("Mapped address spaces:\n\n"));
+ if (gdbarch_addr_bit (target_gdbarch) == 32)
+ {
+ printf_filtered ("\t%10s %10s %10s %10s %7s\n",
+ "Start Addr",
+ " End Addr",
+ " Size", " Offset", "objfile");
+ }
+ else
+ {
+ printf_filtered (" %18s %18s %10s %10s %7s\n",
+ "Start Addr",
+ " End Addr",
+ " Size", " Offset", "objfile");
+ }
+
+ while (read_mapping (procfile, &addr, &endaddr, &permissions[0],
+ &offset, &device[0], &inode, &filename[0]))
+ {
+ size = endaddr - addr;
+
+ /* FIXME: carlton/2003-08-27: Maybe the printf_filtered
+ calls here (and possibly above) should be abstracted
+ out into their own functions? Andrew suggests using
+ a generic local_address_string instead to print out
+ the addresses; that makes sense to me, too. */
+
+ if (gdbarch_addr_bit (target_gdbarch) == 32)
+ {
+ printf_filtered ("\t%#10lx %#10lx %#10x %#10x %7s\n",
+ (unsigned long) addr, /* FIXME: pr_addr */
+ (unsigned long) endaddr,
+ (int) size,
+ (unsigned int) offset,
+ filename[0] ? filename : "");
+ }
+ else
+ {
+ printf_filtered (" %#18lx %#18lx %#10x %#10x %7s\n",
+ (unsigned long) addr, /* FIXME: pr_addr */
+ (unsigned long) endaddr,
+ (int) size,
+ (unsigned int) offset,
+ filename[0] ? filename : "");
+ }
+ }
+
+ do_cleanups (cleanup);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+ if (status_f || all)
+ {
+ sprintf (fname1, "/proc/%ld/status", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
+
+ while (fgets (buffer, sizeof (buffer), procfile) != NULL)
+ puts_filtered (buffer);
+ do_cleanups (cleanup);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+ if (stat_f || all)
+ {
+ sprintf (fname1, "/proc/%ld/stat", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ int itmp;
+ char ctmp;
+ long ltmp;
+ struct cleanup *cleanup = make_cleanup_fclose (procfile);
+
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("Process: %d\n"), itmp);
+ if (fscanf (procfile, "(%[^)]) ", &buffer[0]) > 0)
+ printf_filtered (_("Exec file: %s\n"), buffer);
+ if (fscanf (procfile, "%c ", &ctmp) > 0)
+ printf_filtered (_("State: %c\n"), ctmp);
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("Parent process: %d\n"), itmp);
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("Process group: %d\n"), itmp);
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("Session id: %d\n"), itmp);
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("TTY: %d\n"), itmp);
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("TTY owner process group: %d\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, "%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
+ do_cleanups (cleanup);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+}
+
+/* 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)
+{
+ LONGEST ret;
+ int fd;
+ char filename[64];
+
+ if (object != TARGET_OBJECT_MEMORY || !readbuf)
+ return 0;
+
+ /* Don't bother for one word. */
+ if (len < 3 * sizeof (long))
+ return 0;
+
+ /* We could keep this file open and cache it - possibly one per
+ thread. That requires some juggling, but is even faster. */
+ sprintf (filename, "/proc/%d/mem", PIDGET (inferior_ptid));
+ fd = open (filename, O_RDONLY | O_LARGEFILE);
+ if (fd == -1)
+ return 0;
+
+ /* If pread64 is available, use it. It's faster if the kernel
+ supports it (only one syscall), and it's 64-bit safe even on
+ 32-bit platforms (for instance, SPARC debugging a SPARC64
+ application). */
+#ifdef HAVE_PREAD64
+ if (pread64 (fd, readbuf, len, offset) != len)
+#else
+ if (lseek (fd, offset, SEEK_SET) == -1 || read (fd, readbuf, len) != len)
+#endif
+ ret = 0;
+ else
+ ret = len;
+
+ close (fd);
+ return ret;
+}
+
+
+/* Enumerate spufs IDs for process PID. */
+static LONGEST
+spu_enumerate_spu_ids (int pid, gdb_byte *buf, ULONGEST offset, LONGEST len)
+{
+ enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
+ LONGEST pos = 0;
+ LONGEST written = 0;
+ char path[128];
+ DIR *dir;
+ struct dirent *entry;
+
+ xsnprintf (path, sizeof path, "/proc/%d/fd", pid);
+ dir = opendir (path);
+ if (!dir)
+ return -1;
+
+ rewinddir (dir);
+ while ((entry = readdir (dir)) != NULL)
+ {
+ struct stat st;
+ struct statfs stfs;
+ int fd;
+
+ fd = atoi (entry->d_name);
+ if (!fd)
+ continue;
+
+ xsnprintf (path, sizeof path, "/proc/%d/fd/%d", pid, fd);
+ if (stat (path, &st) != 0)
+ continue;
+ if (!S_ISDIR (st.st_mode))
+ continue;
+
+ if (statfs (path, &stfs) != 0)
+ continue;
+ if (stfs.f_type != SPUFS_MAGIC)
+ continue;
+
+ if (pos >= offset && pos + 4 <= offset + len)
+ {
+ store_unsigned_integer (buf + pos - offset, 4, byte_order, fd);
+ written += 4;
+ }
+ pos += 4;
+ }
+
+ closedir (dir);
+ return written;
+}
+
+/* Implement the to_xfer_partial interface for the TARGET_OBJECT_SPU
+ object type, using the /proc file system. */
+static LONGEST
+linux_proc_xfer_spu (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, LONGEST len)
+{
+ char buf[128];
+ int fd = 0;
+ int ret = -1;
+ int pid = PIDGET (inferior_ptid);
+
+ if (!annex)
+ {
+ if (!readbuf)
+ return -1;
+ else
+ return spu_enumerate_spu_ids (pid, readbuf, offset, len);
+ }
+
+ xsnprintf (buf, sizeof buf, "/proc/%d/fd/%s", pid, annex);
+ fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
+ if (fd <= 0)
+ return -1;
+
+ if (offset != 0
+ && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
+ {
+ close (fd);
+ return 0;
+ }
+
+ if (writebuf)
+ ret = write (fd, writebuf, (size_t) len);
+ else if (readbuf)
+ ret = read (fd, readbuf, (size_t) len);
+
+ close (fd);
+ return ret;
+}
+
+
+/* Parse LINE as a signal set and add its set bits to SIGS. */
+
+static void
+add_line_to_sigset (const char *line, sigset_t *sigs)
+{
+ int len = strlen (line) - 1;
+ const char *p;
+ int signum;
+
+ if (line[len] != '\n')
+ error (_("Could not parse signal set: %s"), line);
+
+ p = line;
+ signum = len * 4;
+ while (len-- > 0)
+ {
+ int digit;
+
+ if (*p >= '0' && *p <= '9')
+ digit = *p - '0';
+ else if (*p >= 'a' && *p <= 'f')
+ digit = *p - 'a' + 10;
+ else
+ error (_("Could not parse signal set: %s"), line);
+
+ signum -= 4;
+
+ if (digit & 1)
+ sigaddset (sigs, signum + 1);
+ if (digit & 2)
+ sigaddset (sigs, signum + 2);
+ if (digit & 4)
+ sigaddset (sigs, signum + 3);
+ if (digit & 8)
+ sigaddset (sigs, signum + 4);
+
+ p++;
+ }
+}
+
+/* Find process PID's pending signals from /proc/pid/status and set
+ SIGS to match. */
+
+void
+linux_proc_pending_signals (int pid, sigset_t *pending,
+ sigset_t *blocked, sigset_t *ignored)
+{
+ FILE *procfile;
+ char buffer[MAXPATHLEN], fname[MAXPATHLEN];
+ struct cleanup *cleanup;
+
+ sigemptyset (pending);
+ sigemptyset (blocked);
+ sigemptyset (ignored);
+ sprintf (fname, "/proc/%d/status", pid);
+ procfile = fopen (fname, "r");
+ if (procfile == NULL)
+ error (_("Could not open %s"), fname);
+ cleanup = make_cleanup_fclose (procfile);
+
+ while (fgets (buffer, MAXPATHLEN, procfile) != NULL)
+ {
+ /* Normal queued signals are on the SigPnd line in the status
+ file. However, 2.6 kernels also have a "shared" pending
+ queue for delivering signals to a thread group, so check for
+ a ShdPnd line also.
+
+ Unfortunately some Red Hat kernels include the shared pending
+ queue but not the ShdPnd status field. */
+
+ if (strncmp (buffer, "SigPnd:\t", 8) == 0)
+ add_line_to_sigset (buffer + 8, pending);
+ else if (strncmp (buffer, "ShdPnd:\t", 8) == 0)
+ add_line_to_sigset (buffer + 8, pending);
+ else if (strncmp (buffer, "SigBlk:\t", 8) == 0)
+ add_line_to_sigset (buffer + 8, blocked);
+ else if (strncmp (buffer, "SigIgn:\t", 8) == 0)
+ add_line_to_sigset (buffer + 8, ignored);
+ }
+
+ do_cleanups (cleanup);
+}
+
+static LONGEST
+linux_nat_xfer_osdata (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
+{
+ /* We make the process list snapshot when the object starts to be
+ read. */
+ static const char *buf;
+ static LONGEST len_avail = -1;
+ static struct obstack obstack;
+
+ DIR *dirp;
+
+ gdb_assert (object == TARGET_OBJECT_OSDATA);
+
+ if (!annex)
+ {
+ if (offset == 0)
+ {
+ if (len_avail != -1 && len_avail != 0)
+ obstack_free (&obstack, NULL);
+ len_avail = 0;
+ buf = NULL;
+ obstack_init (&obstack);
+ obstack_grow_str (&obstack, "<osdata type=\"types\">\n");
+
+ obstack_xml_printf (&obstack,
+ "<item>"
+ "<column name=\"Type\">processes</column>"
+ "<column name=\"Description\">"
+ "Listing of all processes</column>"
+ "</item>");
+
+ obstack_grow_str0 (&obstack, "</osdata>\n");
+ buf = obstack_finish (&obstack);
+ len_avail = strlen (buf);
+ }
+
+ if (offset >= len_avail)
+ {
+ /* Done. Get rid of the obstack. */
+ obstack_free (&obstack, NULL);
+ buf = NULL;
+ len_avail = 0;
+ return 0;
+ }
+
+ if (len > len_avail - offset)
+ len = len_avail - offset;
+ memcpy (readbuf, buf + offset, len);
+
+ return len;
+ }
+
+ if (strcmp (annex, "processes") != 0)
+ return 0;
+
+ gdb_assert (readbuf && !writebuf);
+
+ if (offset == 0)
+ {
+ if (len_avail != -1 && len_avail != 0)
+ obstack_free (&obstack, NULL);
+ len_avail = 0;
+ buf = NULL;
+ obstack_init (&obstack);
+ obstack_grow_str (&obstack, "<osdata type=\"processes\">\n");
+
+ dirp = opendir ("/proc");
+ if (dirp)
+ {
+ struct dirent *dp;
+
+ while ((dp = readdir (dirp)) != NULL)
+ {
+ struct stat statbuf;
+ char procentry[sizeof ("/proc/4294967295")];
+
+ if (!isdigit (dp->d_name[0])
+ || NAMELEN (dp) > sizeof ("4294967295") - 1)
+ continue;
+
+ sprintf (procentry, "/proc/%s", dp->d_name);
+ if (stat (procentry, &statbuf) == 0
+ && S_ISDIR (statbuf.st_mode))
+ {
+ char *pathname;
+ FILE *f;
+ char cmd[MAXPATHLEN + 1];
+ struct passwd *entry;
+
+ pathname = xstrprintf ("/proc/%s/cmdline", dp->d_name);
+ entry = getpwuid (statbuf.st_uid);
+
+ if ((f = fopen (pathname, "r")) != NULL)
+ {
+ size_t length = fread (cmd, 1, sizeof (cmd) - 1, f);
+
+ if (length > 0)
+ {
+ int i;
+
+ for (i = 0; i < length; i++)
+ if (cmd[i] == '\0')
+ cmd[i] = ' ';
+ cmd[length] = '\0';
+
+ obstack_xml_printf (
+ &obstack,
+ "<item>"
+ "<column name=\"pid\">%s</column>"
+ "<column name=\"user\">%s</column>"
+ "<column name=\"command\">%s</column>"
+ "</item>",
+ dp->d_name,
+ entry ? entry->pw_name : "?",
+ cmd);
+ }
+ fclose (f);
+ }
+
+ xfree (pathname);
+ }
+ }
+
+ closedir (dirp);
+ }
+
+ obstack_grow_str0 (&obstack, "</osdata>\n");
+ buf = obstack_finish (&obstack);
+ len_avail = strlen (buf);
+ }
+
+ if (offset >= len_avail)
{
- ptrace (PT_KILL, last.value.related_pid, 0, 0);
- ptrace_wait (null_ptid, &status);
+ /* Done. Get rid of the obstack. */
+ obstack_free (&obstack, NULL);
+ buf = NULL;
+ len_avail = 0;
+ return 0;
}
- /* Kill the current process. */
- ptrace (PT_KILL, pid, 0, 0);
- ret = ptrace_wait (null_ptid, &status);
+ if (len > len_avail - offset)
+ len = len_avail - offset;
+ memcpy (readbuf, buf + offset, len);
+
+ return len;
+}
+
+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 memory_xfer_auxv (ops, object, annex, readbuf, writebuf,
+ offset, len);
- /* We might get a SIGCHLD instead of an exit status. This is
- aggravated by the first kill above - a child has just died. */
+ if (object == TARGET_OBJECT_OSDATA)
+ return linux_nat_xfer_osdata (ops, object, annex, readbuf, writebuf,
+ offset, len);
- while (ret == pid && WIFSTOPPED (status))
+ if (object == TARGET_OBJECT_SPU)
+ return linux_proc_xfer_spu (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
+ /* GDB calculates all the addresses in possibly larget width of the address.
+ Address width needs to be masked before its final use - either by
+ linux_proc_xfer_partial or inf_ptrace_xfer_partial.
+
+ Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */
+
+ if (object == TARGET_OBJECT_MEMORY)
{
- ptrace (PT_KILL, pid, 0, 0);
- ret = ptrace_wait (null_ptid, &status);
+ int addr_bit = gdbarch_addr_bit (target_gdbarch);
+
+ if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT))
+ offset &= ((ULONGEST) 1 << addr_bit) - 1;
}
- target_mourn_inferior ();
+ 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_remove_fork_catchpoint = linux_child_remove_fork_catchpoint;
+ t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint;
+ t->to_remove_vfork_catchpoint = linux_child_remove_vfork_catchpoint;
+ t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint;
+ t->to_remove_exec_catchpoint = linux_child_remove_exec_catchpoint;
+ t->to_set_syscall_catchpoint = linux_child_set_syscall_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;
+}
+
+/* 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 "set target-async" command.
+ Someday, linux will always be async. */
+ return target_async_permitted;
+}
+
+/* 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 "set target-async" command.
+ Someday, linux will always be async. */
+ return target_async_permitted;
+}
+
+static int
+linux_nat_supports_non_stop (void)
+{
+ return 1;
+}
+
+/* True if we want to support multi-process. To be removed when GDB
+ supports multi-exec. */
+
+int linux_multi_process = 1;
+
+static int
+linux_nat_supports_multi_process (void)
+{
+ return linux_multi_process;
+}
+
+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;
+ }
+
+ terminal_inferior ();
+
+ /* Calls to target_terminal_*() are meant to be idempotent. */
+ if (!async_terminal_is_ours)
+ return;
+
+ delete_file_handler (input_fd);
+ async_terminal_is_ours = 0;
+ set_sigint_trap ();
+}
+
+/* target_terminal_ours implementation. */
+
+static void
+linux_nat_terminal_ours (void)
+{
+ if (!target_is_async_p ())
+ {
+ /* Async mode is disabled. */
+ terminal_ours ();
+ return;
+ }
+
+ /* GDB should never give the terminal to the inferior if the
+ inferior is running in the background (run&, continue&, etc.),
+ but claiming it sure should. */
+ terminal_ours ();
+
+ if (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;
+
+/* SIGCHLD handler that serves two purposes: In non-stop/async mode,
+ so we notice when any child changes state, and notify the
+ event-loop; it allows us to use sigsuspend in linux_nat_wait_1
+ above to wait for the arrival of a SIGCHLD. */
+
+static void
+sigchld_handler (int signo)
+{
+ int old_errno = errno;
+
+ if (debug_linux_nat)
+ ui_file_write_async_safe (gdb_stdlog,
+ "sigchld\n", sizeof ("sigchld\n") - 1);
+
+ if (signo == SIGCHLD
+ && linux_nat_event_pipe[0] != -1)
+ async_file_mark (); /* Let the event loop know that there are
+ events to handle. */
+
+ errno = old_errno;
+}
+
+/* Callback registered with the target events file descriptor. */
+
+static void
+handle_target_event (int error, gdb_client_data client_data)
+{
+ (*async_client_callback) (INF_REG_EVENT, async_client_context);
+}
+
+/* Create/destroy the target events pipe. Returns previous state. */
+
+static int
+linux_async_pipe (int enable)
+{
+ int previous = (linux_nat_event_pipe[0] != -1);
+
+ if (previous != enable)
+ {
+ sigset_t prev_mask;
+
+ block_child_signals (&prev_mask);
+
+ if (enable)
+ {
+ 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
+ {
+ close (linux_nat_event_pipe[0]);
+ close (linux_nat_event_pipe[1]);
+ linux_nat_event_pipe[0] = -1;
+ linux_nat_event_pipe[1] = -1;
+ }
+
+ restore_child_signals_mask (&prev_mask);
+ }
+
+ return previous;
+}
+
+/* target_async implementation. */
+
+static void
+linux_nat_async (void (*callback) (enum inferior_event_type event_type,
+ void *context), void *context)
+{
+ if (callback != NULL)
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+ if (!linux_async_pipe (1))
+ {
+ add_file_handler (linux_nat_event_pipe[0],
+ handle_target_event, NULL);
+ /* There may be pending events to handle. Tell the event loop
+ to poll them. */
+ async_file_mark ();
+ }
+ }
+ else
+ {
+ async_client_callback = callback;
+ async_client_context = context;
+ delete_file_handler (linux_nat_event_pipe[0]);
+ linux_async_pipe (0);
+ }
+ return;
+}
+
+/* Stop an LWP, and push a TARGET_SIGNAL_0 stop status if no other
+ event came out. */
+
+static int
+linux_nat_stop_lwp (struct lwp_info *lwp, void *data)
+{
+ if (!lwp->stopped)
+ {
+ ptid_t ptid = lwp->ptid;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNSL: running -> suspending %s\n",
+ target_pid_to_str (lwp->ptid));
+
+
+ stop_callback (lwp, NULL);
+ stop_wait_callback (lwp, NULL);
+
+ /* If the lwp exits while we try to stop it, there's nothing
+ else to do. */
+ lwp = find_lwp_pid (ptid);
+ if (lwp == NULL)
+ return 0;
+
+ /* If we didn't collect any signal other than SIGSTOP while
+ stopping the LWP, push a SIGNAL_0 event. In either case, the
+ event-loop will end up calling target_wait which will collect
+ these. */
+ if (lwp->status == 0)
+ lwp->status = W_STOPCODE (0);
+ async_file_mark ();
+ }
+ else
+ {
+ /* Already known to be stopped; do nothing. */
+
+ if (debug_linux_nat)
+ {
+ if (find_thread_ptid (lwp->ptid)->stop_requested)
+ fprintf_unfiltered (gdb_stdlog,
+ "LNSL: already stopped/stop_requested %s\n",
+ target_pid_to_str (lwp->ptid));
+ else
+ fprintf_unfiltered (gdb_stdlog,
+ "LNSL: already stopped/no "
+ "stop_requested yet %s\n",
+ target_pid_to_str (lwp->ptid));
+ }
+ }
+ return 0;
+}
+
+static void
+linux_nat_stop (ptid_t ptid)
+{
+ if (non_stop)
+ iterate_over_lwps (ptid, linux_nat_stop_lwp, NULL);
+ else
+ linux_ops->to_stop (ptid);
+}
+
+static void
+linux_nat_close (int quitting)
+{
+ /* Unregister from the event loop. */
+ if (target_is_async_p ())
+ target_async (NULL, 0);
+
+ if (linux_ops->to_close)
+ linux_ops->to_close (quitting);
+}
+
+/* When requests are passed down from the linux-nat layer to the
+ single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are
+ used. The address space pointer is stored in the inferior object,
+ but the common code that is passed such ptid can't tell whether
+ lwpid is a "main" process id or not (it assumes so). We reverse
+ look up the "main" process id from the lwp here. */
+
+struct address_space *
+linux_nat_thread_address_space (struct target_ops *t, ptid_t ptid)
+{
+ struct lwp_info *lwp;
+ struct inferior *inf;
+ int pid;
+
+ pid = GET_LWP (ptid);
+ if (GET_LWP (ptid) == 0)
+ {
+ /* An (lwpid,0,0) ptid. Look up the lwp object to get at the
+ tgid. */
+ lwp = find_lwp_pid (ptid);
+ pid = GET_PID (lwp->ptid);
+ }
+ else
+ {
+ /* A (pid,lwpid,0) ptid. */
+ pid = GET_PID (ptid);
+ }
+
+ inf = find_inferior_pid (pid);
+ gdb_assert (inf != NULL);
+ return inf->aspace;
+}
+
+int
+linux_nat_core_of_thread_1 (ptid_t ptid)
+{
+ struct cleanup *back_to;
+ char *filename;
+ FILE *f;
+ char *content = NULL;
+ char *p;
+ char *ts = 0;
+ int content_read = 0;
+ int i;
+ int core;
+
+ filename = xstrprintf ("/proc/%d/task/%ld/stat",
+ GET_PID (ptid), GET_LWP (ptid));
+ back_to = make_cleanup (xfree, filename);
+
+ f = fopen (filename, "r");
+ if (!f)
+ {
+ do_cleanups (back_to);
+ return -1;
+ }
+
+ make_cleanup_fclose (f);
+
+ for (;;)
+ {
+ int n;
+
+ content = xrealloc (content, content_read + 1024);
+ n = fread (content + content_read, 1, 1024, f);
+ content_read += n;
+ if (n < 1024)
+ {
+ content[content_read] = '\0';
+ break;
+ }
+ }
+
+ make_cleanup (xfree, content);
+
+ p = strchr (content, '(');
+
+ /* Skip ")". */
+ if (p != NULL)
+ p = strchr (p, ')');
+ if (p != NULL)
+ p++;
+
+ /* If the first field after program name has index 0, then core number is
+ the field with index 36. There's no constant for that anywhere. */
+ if (p != NULL)
+ p = strtok_r (p, " ", &ts);
+ for (i = 0; p != NULL && i != 36; ++i)
+ p = strtok_r (NULL, " ", &ts);
+
+ if (p == NULL || sscanf (p, "%d", &core) == 0)
+ core = -1;
+
+ do_cleanups (back_to);
+
+ return core;
+}
+
+/* Return the cached value of the processor core for thread PTID. */
+
+int
+linux_nat_core_of_thread (struct target_ops *ops, ptid_t ptid)
+{
+ struct lwp_info *info = find_lwp_pid (ptid);
+
+ if (info)
+ return info->core;
+ return -1;
+}
+
+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_pass_signals = linux_nat_pass_signals;
+ 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_thread_name = linux_nat_thread_name;
+ t->to_has_thread_control = tc_schedlock;
+ t->to_thread_address_space = linux_nat_thread_address_space;
+ t->to_stopped_by_watchpoint = linux_nat_stopped_by_watchpoint;
+ t->to_stopped_data_address = linux_nat_stopped_data_address;
+
+ t->to_can_async_p = linux_nat_can_async_p;
+ t->to_is_async_p = linux_nat_is_async_p;
+ t->to_supports_non_stop = linux_nat_supports_non_stop;
+ t->to_async = linux_nat_async;
+ t->to_terminal_inferior = linux_nat_terminal_inferior;
+ t->to_terminal_ours = linux_nat_terminal_ours;
+ t->to_close = linux_nat_close;
+
+ /* Methods for non-stop support. */
+ t->to_stop = linux_nat_stop;
+
+ t->to_supports_multi_process = linux_nat_supports_multi_process;
+
+ t->to_core_of_thread = linux_nat_core_of_thread;
+
+ /* 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);
+}
+
+/* Register a method to call whenever a new thread is attached. */
+void
+linux_nat_set_new_thread (struct target_ops *t, void (*new_thread) (ptid_t))
+{
+ /* Save the pointer. We only support a single registered instance
+ of the GNU/Linux native target, so we do not need to map this to
+ T. */
+ linux_nat_new_thread = new_thread;
+}
+
+/* Register a method that converts a siginfo object between the layout
+ that ptrace returns, and the layout in the architecture of the
+ inferior. */
+void
+linux_nat_set_siginfo_fixup (struct target_ops *t,
+ int (*siginfo_fixup) (struct siginfo *,
+ gdb_byte *,
+ int))
+{
+ /* Save the pointer. */
+ linux_nat_siginfo_fixup = siginfo_fixup;
+}
+
+/* Return the saved siginfo associated with PTID. */
+struct siginfo *
+linux_nat_get_siginfo (ptid_t ptid)
+{
+ struct lwp_info *lp = find_lwp_pid (ptid);
+
+ gdb_assert (lp != NULL);
+
+ return &lp->siginfo;
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes. */
+extern initialize_file_ftype _initialize_linux_nat;
+
+void
+_initialize_linux_nat (void)
+{
+ add_info ("proc", linux_nat_info_proc_cmd, _("\
+Show /proc process information about any running process.\n\
+Specify any process id, or use the program being debugged by default.\n\
+Specify any of the following keywords for detailed info:\n\
+ mappings -- list of mapped memory regions.\n\
+ stat -- list a bunch of random process info.\n\
+ status -- list a different bunch of random process info.\n\
+ all -- list all available /proc info."));
+
+ 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);
+
+ /* Save this mask as the default. */
+ sigprocmask (SIG_SETMASK, NULL, &normal_mask);
+
+ /* Install a SIGCHLD handler. */
+ sigchld_action.sa_handler = sigchld_handler;
+ sigemptyset (&sigchld_action.sa_mask);
+ sigchld_action.sa_flags = SA_RESTART;
+
+ /* Make it the default. */
+ sigaction (SIGCHLD, &sigchld_action, NULL);
+
+ /* Make sure we don't block SIGCHLD during a sigsuspend. */
+ sigprocmask (SIG_SETMASK, NULL, &suspend_mask);
+ sigdelset (&suspend_mask, SIGCHLD);
+
+ sigemptyset (&blocked_mask);
+
+ add_setshow_boolean_cmd ("disable-randomization", class_support,
+ &disable_randomization, _("\
+Set disabling of debuggee's virtual address space randomization."), _("\
+Show disabling of debuggee's virtual address space randomization."), _("\
+When this mode is on (which is the default), randomization of the virtual\n\
+address space is disabled. Standalone programs run with the randomization\n\
+enabled by default on some platforms."),
+ &set_disable_randomization,
+ &show_disable_randomization,
+ &setlist, &showlist);
+}
+\f
+
+/* FIXME: kettenis/2000-08-26: The stuff on this page is specific to
+ the GNU/Linux Threads library and therefore doesn't really belong
+ here. */
+
+/* Read variable NAME in the target and return its value if found.
+ Otherwise return zero. It is assumed that the type of the variable
+ is `int'. */
+
+static int
+get_signo (const char *name)
+{
+ struct minimal_symbol *ms;
+ int signo;
+
+ ms = lookup_minimal_symbol (name, NULL, NULL);
+ if (ms == NULL)
+ return 0;
+
+ if (target_read_memory (SYMBOL_VALUE_ADDRESS (ms), (gdb_byte *) &signo,
+ sizeof (signo)) != 0)
+ return 0;
+
+ return signo;
+}
+
+/* Return the set of signals used by the threads library in *SET. */
+
+void
+lin_thread_get_thread_signals (sigset_t *set)
+{
+ struct sigaction action;
+ int restart, cancel;
+
+ 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)
+ restart = __SIGRTMIN;
+
+ if (cancel == 0)
+ cancel = __SIGRTMIN + 1;
+
+ sigaddset (set, restart);
+ sigaddset (set, cancel);
+
+ /* The GNU/Linux Threads library makes terminating threads send a
+ special "cancel" signal instead of SIGCHLD. Make sure we catch
+ those (to prevent them from terminating GDB itself, which is
+ likely to be their default action) and treat them the same way as
+ SIGCHLD. */
+
+ action.sa_handler = sigchld_handler;
+ sigemptyset (&action.sa_mask);
+ action.sa_flags = SA_RESTART;
+ sigaction (cancel, &action, NULL);
+
+ /* We block the "cancel" signal throughout this code ... */
+ sigaddset (&blocked_mask, cancel);
+ sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
+
+ /* ... except during a sigsuspend. */
+ sigdelset (&suspend_mask, cancel);
}
projects / deliverable / binutils-gdb.git / blobdiff