/* GNU/Linux native-dependent code common to multiple platforms.
- Copyright (C) 2003 Free Software Foundation, Inc.
+
+ Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ 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-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 */
+
+#ifndef O_LARGEFILE
+#define O_LARGEFILE 0
+#endif
/* If the system headers did not provide the constants, hard-code the normal
values. */
#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_VFORK_DONE 5
+#define PTRACE_EVENT_EXIT 6
#endif /* PTRACE_EVENT_FORK */
#define __WALL 0x40000000 /* Wait for any child. */
#endif
+/* The single-threaded native GNU/Linux target_ops. We save a pointer for
+ the use of the multi-threaded target. */
+static struct target_ops *linux_ops;
+static struct target_ops linux_ops_saved;
+
+/* The 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 linux_parent_pid;
+
+struct simple_pid_list
+{
+ int pid;
+ int status;
+ struct simple_pid_list *next;
+};
+struct simple_pid_list *stopped_pids;
+
/* This variable is a tri-state flag: -1 for unknown, 0 if PTRACE_O_TRACEFORK
can not be used, 1 if it can. */
static int linux_supports_tracefork_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;
+
+\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, 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, int *status)
+{
+ struct simple_pid_list **p;
+
+ for (p = listp; *p != NULL; p = &(*p)->next)
+ if ((*p)->pid == pid)
+ {
+ struct simple_pid_list *next = (*p)->next;
+ *status = (*p)->status;
+ xfree (*p);
+ *p = next;
+ return 1;
+ }
+ return 0;
+}
+
+static void
+linux_record_stopped_pid (int pid, int status)
+{
+ add_to_pid_list (&stopped_pids, pid, status);
+}
+
\f
/* A helper function for linux_test_for_tracefork, called after fork (). */
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 *status, int flags)
+{
+ int ret;
+ do
+ {
+ ret = waitpid (pid, status, 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;
+ linux_supports_tracefork_flag = 0;
+ linux_supports_tracevforkdone_flag = 0;
+
+ ret = ptrace (PTRACE_SETOPTIONS, original_pid, 0, PTRACE_O_TRACEFORK);
+ if (ret != 0)
+ 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"));
+ 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);
+
return;
}
- ptrace (PTRACE_CONT, child_pid, 0, 0);
- ret = waitpid (child_pid, &status, 0);
+ /* Check whether PTRACE_O_TRACEVFORKDONE is available. */
+ ret = ptrace (PTRACE_SETOPTIONS, child_pid, 0,
+ PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORKDONE);
+ linux_supports_tracevforkdone_flag = (ret == 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);
}
/* 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 (int pid)
+{
+ if (linux_supports_tracefork_flag == -1)
+ linux_test_for_tracefork (pid);
+ return linux_supports_tracevforkdone_flag;
+}
+
\f
-int
-child_insert_fork_catchpoint (int pid)
+void
+linux_enable_event_reporting (ptid_t ptid)
+{
+ int pid = ptid_get_lwp (ptid);
+ int options;
+
+ if (pid == 0)
+ pid = ptid_get_pid (ptid);
+
+ if (! linux_supports_tracefork (pid))
+ return;
+
+ options = PTRACE_O_TRACEFORK | PTRACE_O_TRACEVFORK | PTRACE_O_TRACEEXEC
+ | PTRACE_O_TRACECLONE;
+ if (linux_supports_tracevforkdone (pid))
+ 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);
+}
+
+static void
+linux_child_post_attach (int pid)
+{
+ linux_enable_event_reporting (pid_to_ptid (pid));
+ check_for_thread_db ();
+}
+
+static void
+linux_child_post_startup_inferior (ptid_t ptid)
+{
+ linux_enable_event_reporting (ptid);
+ check_for_thread_db ();
+}
+
+static int
+linux_child_follow_fork (struct target_ops *ops, int follow_child)
{
- if (linux_supports_tracefork ())
- error ("Fork catchpoints have not been implemented yet.");
+ ptid_t last_ptid;
+ struct target_waitstatus last_status;
+ 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_lwp (last_ptid);
+ if (parent_pid == 0)
+ parent_pid = ptid_get_pid (last_ptid);
+ child_pid = last_status.value.related_pid;
+
+ if (! follow_child)
+ {
+ /* We're already attached to the parent, by default. */
+
+ /* 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);
+
+ /* Detach new forked process? */
+ if (detach_fork)
+ {
+ if (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 fork_info *fp;
+ /* Retain child fork in ptrace (stopped) state. */
+ fp = find_fork_pid (child_pid);
+ if (!fp)
+ fp = add_fork (child_pid);
+ fork_save_infrun_state (fp, 0);
+ }
+
+ if (has_vforked)
+ {
+ gdb_assert (linux_supports_tracefork_flag >= 0);
+ if (linux_supports_tracevforkdone (0))
+ {
+ int status;
+
+ ptrace (PTRACE_CONT, parent_pid, 0, 0);
+ my_waitpid (parent_pid, &status, __WALL);
+ if ((status >> 16) != PTRACE_EVENT_VFORK_DONE)
+ warning (_("Unexpected waitpid result %06x when waiting for "
+ "vfork-done"), status);
+ }
+ else
+ {
+ /* We can't insert breakpoints until the child has
+ finished with the shared memory region. We need to
+ wait until that happens. Ideal would be to just
+ call:
+ - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0);
+ - waitpid (parent_pid, &status, __WALL);
+ However, most architectures can't handle a syscall
+ being traced on the way out if it wasn't traced on
+ the way in.
+
+ We might also think to loop, continuing the child
+ until it exits or gets a SIGTRAP. One problem is
+ that the child might call ptrace with PTRACE_TRACEME.
+
+ There's no simple and reliable way to figure out when
+ the vforked child will be done with its copy of the
+ shared memory. We could step it out of the syscall,
+ two instructions, let it go, and then single-step the
+ parent once. When we have hardware single-step, this
+ would work; with software single-step it could still
+ be made to work but we'd have to be able to insert
+ single-step breakpoints in the child, and we'd have
+ to insert -just- the single-step breakpoint in the
+ parent. Very awkward.
+
+ In the end, the best we can do is to make sure it
+ runs for a little while. Hopefully it will be out of
+ range of any breakpoints we reinsert. Usually this
+ is only the single-step breakpoint at vfork's return
+ point. */
+
+ usleep (10000);
+ }
+
+ /* Since we vforked, breakpoints were removed in the parent
+ too. Put them back. */
+ reattach_breakpoints (parent_pid);
+ }
+ }
else
- error ("Your system does not support fork catchpoints.");
+ {
+ char child_pid_spelling[40];
+
+ /* Needed to keep the breakpoint lists in sync. */
+ if (! has_vforked)
+ detach_breakpoints (child_pid);
+
+ /* Before detaching from the parent, remove all breakpoints from it. */
+ remove_breakpoints ();
+
+ if (debug_linux_nat)
+ {
+ target_terminal_ours ();
+ fprintf_filtered (gdb_stdlog,
+ "Attaching after fork to child process %d.\n",
+ child_pid);
+ }
+
+ /* If we're vforking, we may want to hold on to the parent until
+ the child exits or execs. At exec time we can remove the old
+ 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).
+
+ 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).
+
+ 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 (has_vforked)
+ linux_parent_pid = parent_pid;
+ else if (!detach_fork)
+ {
+ struct fork_info *fp;
+ /* Retain parent fork in ptrace (stopped) state. */
+ fp = find_fork_pid (parent_pid);
+ if (!fp)
+ fp = add_fork (parent_pid);
+ fork_save_infrun_state (fp, 0);
+ }
+ else
+ {
+ target_detach (NULL, 0);
+ }
+
+ inferior_ptid = pid_to_ptid (child_pid);
+
+ /* Reinstall ourselves, since we might have been removed in
+ target_detach (which does other necessary cleanup). */
+
+ push_target (ops);
+
+ /* Reset breakpoints in the child as appropriate. */
+ follow_inferior_reset_breakpoints ();
+ }
+
+ return 0;
}
-int
-child_insert_vfork_catchpoint (int pid)
+\f
+static void
+linux_child_insert_fork_catchpoint (int pid)
+{
+ if (! linux_supports_tracefork (pid))
+ error (_("Your system does not support fork catchpoints."));
+}
+
+static void
+linux_child_insert_vfork_catchpoint (int pid)
+{
+ if (!linux_supports_tracefork (pid))
+ error (_("Your system does not support vfork catchpoints."));
+}
+
+static void
+linux_child_insert_exec_catchpoint (int pid)
+{
+ if (!linux_supports_tracefork (pid))
+ error (_("Your system does not support exec catchpoints."));
+}
+
+/* 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. */
+static struct lwp_info *lwp_list;
+
+/* Number of LWPs in the list. */
+static int num_lwps;
+\f
+
+#define GET_LWP(ptid) ptid_get_lwp (ptid)
+#define GET_PID(ptid) ptid_get_pid (ptid)
+#define is_lwp(ptid) (GET_LWP (ptid) != 0)
+#define BUILD_LWP(lwp, pid) ptid_build (pid, lwp, 0)
+
+/* If the last reported event was a SIGTRAP, this variable is set to
+ the process id of the LWP/thread that got it. */
+ptid_t trap_ptid;
+\f
+
+/* Since we cannot wait (in linux_nat_wait) for the initial process and
+ any cloned processes with a single call to waitpid, we have to use
+ the WNOHANG flag and call waitpid in a loop. To optimize
+ things a bit we use `sigsuspend' to wake us up when a process has
+ something to report (it will send us a SIGCHLD if it has). To make
+ this work we have to juggle with the signal mask. We save the
+ original signal mask such that we can restore it before creating a
+ new process in order to avoid blocking certain signals in the
+ inferior. We then block SIGCHLD during the waitpid/sigsuspend
+ loop. */
+
+/* Original signal mask. */
+static sigset_t normal_mask;
+
+/* 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;
+\f
+
+/* Prototypes for local functions. */
+static int stop_wait_callback (struct lwp_info *lp, void *data);
+static int linux_nat_thread_alive (ptid_t ptid);
+static char *linux_child_pid_to_exec_file (int pid);
+\f
+/* Convert wait status STATUS to a string. Used for printing debug
+ messages only. */
+
+static char *
+status_to_str (int status)
{
- if (linux_supports_tracefork ())
- error ("Vfork catchpoints have not been implemented yet.");
+ static char buf[64];
+
+ if (WIFSTOPPED (status))
+ snprintf (buf, sizeof (buf), "%s (stopped)",
+ strsignal (WSTOPSIG (status)));
+ else if (WIFSIGNALED (status))
+ snprintf (buf, sizeof (buf), "%s (terminated)",
+ strsignal (WSTOPSIG (status)));
else
- error ("Your system does not support vfork catchpoints.");
+ snprintf (buf, sizeof (buf), "%d (exited)", WEXITSTATUS (status));
+
+ return buf;
}
-int
-child_insert_exec_catchpoint (int pid)
+/* Initialize the list of LWPs. Note that this module, contrary to
+ what GDB's generic threads layer does for its thread list,
+ re-initializes the LWP lists whenever we mourn or detach (which
+ doesn't involve mourning) the inferior. */
+
+static void
+init_lwp_list (void)
+{
+ struct lwp_info *lp, *lpnext;
+
+ for (lp = lwp_list; lp; lp = lpnext)
+ {
+ lpnext = lp->next;
+ xfree (lp);
+ }
+
+ lwp_list = NULL;
+ num_lwps = 0;
+}
+
+/* Add the LWP specified by PID to the list. Return a pointer to the
+ structure describing the new 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->next = lwp_list;
+ lwp_list = lp;
+ ++num_lwps;
+
+ 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;
+
+ num_lwps--;
+
+ 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)
{
- if (linux_supports_tracefork ())
- error ("Exec catchpoints have not been implemented yet.");
+ 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 (int (*callback) (struct lwp_info *, void *), void *data)
+{
+ struct lwp_info *lp, *lpnext;
+
+ for (lp = lwp_list; lp; lp = lpnext)
+ {
+ lpnext = lp->next;
+ if ((*callback) (lp, data))
+ return lp;
+ }
+
+ return NULL;
+}
+
+/* Update our internal state when changing from one fork (checkpoint,
+ et cetera) to another indicated by NEW_PTID. We can only switch
+ single-threaded applications, so we only create one new LWP, and
+ the previous list is discarded. */
+
+void
+linux_nat_switch_fork (ptid_t new_ptid)
+{
+ struct lwp_info *lp;
+
+ init_lwp_list ();
+ lp = add_lwp (new_ptid);
+ lp->stopped = 1;
+}
+
+/* Record a PTID for later deletion. */
+
+struct saved_ptids
+{
+ ptid_t ptid;
+ struct saved_ptids *next;
+};
+static struct saved_ptids *threads_to_delete;
+
+static void
+record_dead_thread (ptid_t ptid)
+{
+ struct saved_ptids *p = xmalloc (sizeof (struct saved_ptids));
+ p->ptid = ptid;
+ p->next = threads_to_delete;
+ threads_to_delete = p;
+}
+
+/* Delete any dead threads which are not the current thread. */
+
+static void
+prune_lwps (void)
+{
+ struct saved_ptids **p = &threads_to_delete;
+
+ while (*p)
+ if (! ptid_equal ((*p)->ptid, inferior_ptid))
+ {
+ struct saved_ptids *tmp = *p;
+ delete_thread (tmp->ptid);
+ *p = tmp->next;
+ xfree (tmp);
+ }
+ else
+ p = &(*p)->next;
+}
+
+/* Callback for iterate_over_threads that finds a thread corresponding
+ to the given LWP. */
+
+static int
+find_thread_from_lwp (struct thread_info *thr, void *dummy)
+{
+ ptid_t *ptid_p = dummy;
+
+ if (GET_LWP (thr->ptid) && GET_LWP (thr->ptid) == GET_LWP (*ptid_p))
+ return 1;
+ else
+ return 0;
+}
+
+/* Handle the exit of a single thread LP. */
+
+static void
+exit_lwp (struct lwp_info *lp)
+{
+ if (in_thread_list (lp->ptid))
+ {
+ /* Core GDB cannot deal with us deleting the current thread. */
+ if (!ptid_equal (lp->ptid, inferior_ptid))
+ delete_thread (lp->ptid);
+ else
+ record_dead_thread (lp->ptid);
+ printf_unfiltered (_("[%s exited]\n"),
+ target_pid_to_str (lp->ptid));
+ }
else
- error ("Your system does not support exec catchpoints.");
+ {
+ /* Even if LP->PTID is not in the global GDB thread list, the
+ LWP may be - with an additional thread ID. We don't need
+ to print anything in this case; thread_db is in use and
+ already took care of that. But it didn't delete the thread
+ in order to handle zombies correctly. */
+
+ struct thread_info *thr;
+
+ thr = iterate_over_threads (find_thread_from_lwp, &lp->ptid);
+ if (thr)
+ {
+ if (!ptid_equal (thr->ptid, inferior_ptid))
+ delete_thread (thr->ptid);
+ else
+ record_dead_thread (thr->ptid);
+ }
+ }
+
+ delete_lwp (lp->ptid);
}
+/* Attach to the LWP specified by PID. If VERBOSE is non-zero, print
+ a message telling the user that a new LWP has been added to the
+ process. Return 0 if successful or -1 if the new LWP could not
+ be attached. */
+
+int
+lin_lwp_attach_lwp (ptid_t ptid, int verbose)
+{
+ struct lwp_info *lp;
+
+ gdb_assert (is_lwp (ptid));
+
+ /* Make sure SIGCHLD is blocked. We don't want SIGCHLD events
+ to interrupt either the ptrace() or waitpid() calls below. */
+ if (!sigismember (&blocked_mask, SIGCHLD))
+ {
+ sigaddset (&blocked_mask, SIGCHLD);
+ sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
+ }
+
+ 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)
+ {
+ pid_t pid;
+ int status;
+
+ if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
+ {
+ /* If we fail to attach to the thread, issue a warning,
+ but continue. One way this can happen is if thread
+ creation is interrupted; as of Linux 2.6.19, a kernel
+ bug may place threads in the thread list and then fail
+ to create them. */
+ warning (_("Can't attach %s: %s"), target_pid_to_str (ptid),
+ safe_strerror (errno));
+ return -1;
+ }
+
+ if (lp == NULL)
+ lp = add_lwp (ptid);
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
+ target_pid_to_str (ptid));
+
+ pid = my_waitpid (GET_LWP (ptid), &status, 0);
+ if (pid == -1 && errno == ECHILD)
+ {
+ /* Try again with __WCLONE to check cloned processes. */
+ pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE);
+ lp->cloned = 1;
+ }
+
+ gdb_assert (pid == GET_LWP (ptid)
+ && WIFSTOPPED (status) && WSTOPSIG (status));
+
+ target_post_attach (pid);
+
+ lp->stopped = 1;
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "LLAL: waitpid %s received %s\n",
+ target_pid_to_str (ptid),
+ status_to_str (status));
+ }
+ }
+ else
+ {
+ /* We assume that the LWP representing the original process is
+ already stopped. Mark it as stopped in the data structure
+ that the GNU/linux ptrace layer uses to keep track of
+ threads. Note that this won't have already been done since
+ the main thread will have, we assume, been stopped by an
+ attach from a different layer. */
+ if (lp == NULL)
+ lp = add_lwp (ptid);
+ lp->stopped = 1;
+ }
+
+ if (verbose)
+ printf_filtered (_("[New %s]\n"), target_pid_to_str (ptid));
+
+ return 0;
+}
+
+static void
+linux_nat_attach (char *args, int from_tty)
+{
+ struct lwp_info *lp;
+ pid_t pid;
+ int status;
+
+ /* FIXME: We should probably accept a list of process id's, and
+ attach all of them. */
+ linux_ops->to_attach (args, from_tty);
+
+ /* Add the initial process as the first LWP to the list. */
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
+ lp = add_lwp (inferior_ptid);
+
+ /* Make sure the initial process is stopped. The user-level threads
+ layer might want to poke around in the inferior, and that won't
+ work if things haven't stabilized yet. */
+ pid = my_waitpid (GET_PID (inferior_ptid), &status, 0);
+ if (pid == -1 && errno == ECHILD)
+ {
+ warning (_("%s is a cloned process"), target_pid_to_str (inferior_ptid));
+
+ /* Try again with __WCLONE to check cloned processes. */
+ pid = my_waitpid (GET_PID (inferior_ptid), &status, __WCLONE);
+ lp->cloned = 1;
+ }
+
+ gdb_assert (pid == GET_PID (inferior_ptid)
+ && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP);
+
+ lp->stopped = 1;
+
+ /* Fake the SIGSTOP that core GDB expects. */
+ lp->status = W_STOPCODE (SIGSTOP);
+ lp->resumed = 1;
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "LLA: waitpid %ld, faking SIGSTOP\n", (long) pid);
+ }
+}
+
+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));
+
+ while (lp->signalled && lp->stopped)
+ {
+ errno = 0;
+ if (ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0,
+ WSTOPSIG (lp->status)) < 0)
+ error (_("Can't continue %s: %s"), target_pid_to_str (lp->ptid),
+ safe_strerror (errno));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "DC: PTRACE_CONTINUE (%s, 0, %s) (OK)\n",
+ target_pid_to_str (lp->ptid),
+ status_to_str (lp->status));
+
+ lp->stopped = 0;
+ lp->signalled = 0;
+ lp->status = 0;
+ /* FIXME drow/2003-08-26: There was a call to stop_wait_callback
+ here. But since lp->signalled was cleared above,
+ stop_wait_callback didn't do anything; the process was left
+ running. Shouldn't we be waiting for it to stop?
+ I've removed the call, since stop_wait_callback now does do
+ something when called with lp->signalled == 0. */
+
+ gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status));
+ }
+
+ /* We don't actually detach from the LWP that has an id equal to the
+ overall process id just yet. */
+ if (GET_LWP (lp->ptid) != GET_PID (lp->ptid))
+ {
+ errno = 0;
+ if (ptrace (PTRACE_DETACH, GET_LWP (lp->ptid), 0,
+ WSTOPSIG (lp->status)) < 0)
+ error (_("Can't detach %s: %s"), target_pid_to_str (lp->ptid),
+ safe_strerror (errno));
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "PTRACE_DETACH (%s, %s, 0) (OK)\n",
+ target_pid_to_str (lp->ptid),
+ strsignal (WSTOPSIG (lp->status)));
+
+ delete_lwp (lp->ptid);
+ }
+
+ return 0;
+}
+
+static void
+linux_nat_detach (char *args, int from_tty)
+{
+ iterate_over_lwps (detach_callback, NULL);
+
+ /* Only the initial process should be left right now. */
+ gdb_assert (num_lwps == 1);
+
+ trap_ptid = null_ptid;
+
+ /* Destroy LWP info; it's no longer valid. */
+ init_lwp_list ();
+
+ /* Restore the original signal mask. */
+ sigprocmask (SIG_SETMASK, &normal_mask, NULL);
+ sigemptyset (&blocked_mask);
+
+ inferior_ptid = pid_to_ptid (GET_PID (inferior_ptid));
+ linux_ops->to_detach (args, from_tty);
+}
+
+/* Resume LP. */
+
+static int
+resume_callback (struct lwp_info *lp, void *data)
+{
+ if (lp->stopped && lp->status == 0)
+ {
+ struct thread_info *tp;
+
+ linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ 0, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ 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;
+ }
+
+ 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 (ptid_t ptid, int step, enum target_signal signo)
+{
+ struct lwp_info *lp;
+ int resume_all;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Preparing to %s %s, %s, inferior_ptid %s\n",
+ step ? "step" : "resume",
+ target_pid_to_str (ptid),
+ signo ? strsignal (signo) : "0",
+ target_pid_to_str (inferior_ptid));
+
+ prune_lwps ();
+
+ /* A specific PTID means `step only this process id'. */
+ resume_all = (PIDGET (ptid) == -1);
+
+ if (resume_all)
+ iterate_over_lwps (resume_set_callback, NULL);
+ else
+ iterate_over_lwps (resume_clear_callback, NULL);
+
+ /* If PID is -1, it's the current inferior that should be
+ handled specially. */
+ if (PIDGET (ptid) == -1)
+ ptid = inferior_ptid;
+
+ lp = find_lwp_pid (ptid);
+ if (lp)
+ {
+ ptid = pid_to_ptid (GET_LWP (lp->ptid));
+
+ /* Remember if we're stepping. */
+ lp->step = step;
+
+ /* Mark this LWP as resumed. */
+ lp->resumed = 1;
+
+ /* If we have a pending wait status for this thread, there is no
+ point in resuming the process. But first make sure that
+ linux_nat_wait won't preemptively handle the event - we
+ should never take this short-circuit if we are going to
+ leave LP running, since we have skipped resuming all the
+ other threads. This bit of code needs to be synchronized
+ with linux_nat_wait. */
+
+ if (lp->status && WIFSTOPPED (lp->status))
+ {
+ int saved_signo = target_signal_from_host (WSTOPSIG (lp->status));
+
+ if (signal_stop_state (saved_signo) == 0
+ && signal_print_state (saved_signo) == 0
+ && signal_pass_state (saved_signo) == 1)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Not short circuiting for ignored "
+ "status 0x%x\n", lp->status);
+
+ /* FIXME: What should we do if we are supposed to continue
+ this thread with a signal? */
+ gdb_assert (signo == TARGET_SIGNAL_0);
+ signo = saved_signo;
+ lp->status = 0;
+ }
+ }
+
+ if (lp->status)
+ {
+ /* FIXME: What should we do if we are supposed to continue
+ this thread with a signal? */
+ gdb_assert (signo == TARGET_SIGNAL_0);
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: Short circuiting for status 0x%x\n",
+ lp->status);
+
+ return;
+ }
+
+ /* Mark LWP as not stopped to prevent it from being continued by
+ resume_callback. */
+ lp->stopped = 0;
+ }
+
+ if (resume_all)
+ iterate_over_lwps (resume_callback, NULL);
+
+ linux_ops->to_resume (ptid, step, signo);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLR: %s %s, %s (resume event thread)\n",
+ step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (ptid),
+ signo ? strsignal (signo) : "0");
+}
+
+/* Issue kill to specified lwp. */
+
+static int tkill_failed;
+
+static int
+kill_lwp (int lwpid, int signo)
+{
+ errno = 0;
+
+/* 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
+ if (!tkill_failed)
+ {
+ int ret = syscall (__NR_tkill, lwpid, signo);
+ if (errno != ENOSYS)
+ return ret;
+ errno = 0;
+ tkill_failed = 1;
+ }
+#endif
+
+ return kill (lwpid, signo);
+}
+
+/* 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;
+ struct lwp_info *new_lp = NULL;
+ 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 = new_pid;
+
+ if (event == PTRACE_EVENT_FORK)
+ ourstatus->kind = TARGET_WAITKIND_FORKED;
+ else if (event == PTRACE_EVENT_VFORK)
+ ourstatus->kind = TARGET_WAITKIND_VFORKED;
+ else
+ {
+ ourstatus->kind = TARGET_WAITKIND_IGNORE;
+ new_lp = add_lwp (BUILD_LWP (new_pid, GET_PID (inferior_ptid)));
+ new_lp->cloned = 1;
+
+ if (WSTOPSIG (status) != SIGSTOP)
+ {
+ /* This can happen if someone starts sending signals to
+ the new thread before it gets a chance to run, which
+ have a lower number than SIGSTOP (e.g. SIGUSR1).
+ This is an unlikely case, and harder to handle for
+ fork / vfork than for clone, so we do not try - but
+ we handle it for clone events here. We'll send
+ the other signal on to the thread below. */
+
+ new_lp->signalled = 1;
+ }
+ else
+ status = 0;
+
+ if (stopping)
+ new_lp->stopped = 1;
+ else
+ {
+ new_lp->resumed = 1;
+ ptrace (PTRACE_CONT, lp->waitstatus.value.related_pid, 0,
+ status ? WSTOPSIG (status) : 0);
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LHEW: Got clone event from LWP %ld, resuming\n",
+ GET_LWP (lp->ptid));
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+
+ return 1;
+ }
+
+ return 0;
+ }
+
+ if (event == PTRACE_EVENT_EXEC)
+ {
+ ourstatus->kind = TARGET_WAITKIND_EXECD;
+ ourstatus->value.execd_pathname
+ = xstrdup (linux_child_pid_to_exec_file (pid));
+
+ if (linux_parent_pid)
+ {
+ detach_breakpoints (linux_parent_pid);
+ ptrace (PTRACE_DETACH, linux_parent_pid, 0, 0);
+
+ linux_parent_pid = 0;
+ }
+
+ return 0;
+ }
+
+ internal_error (__FILE__, __LINE__,
+ _("unknown ptrace event %d"), event);
+}
+
+/* Wait for LP to stop. Returns the wait status, or 0 if the LWP has
+ exited. */
+
+static int
+wait_lwp (struct lwp_info *lp)
+{
+ pid_t pid;
+ int status;
+ int thread_dead = 0;
+
+ gdb_assert (!lp->stopped);
+ gdb_assert (lp->status == 0);
+
+ pid = my_waitpid (GET_LWP (lp->ptid), &status, 0);
+ if (pid == -1 && errno == ECHILD)
+ {
+ pid = my_waitpid (GET_LWP (lp->ptid), &status, __WCLONE);
+ 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 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;
+}
+
+/* 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;
+}
+
+/* Wait until LP is stopped. If DATA is non-null it is interpreted as
+ a pointer to a set of signals to be flushed immediately. */
+
+static int
+stop_wait_callback (struct lwp_info *lp, void *data)
+{
+ sigset_t *flush_mask = data;
+
+ if (!lp->stopped)
+ {
+ int status;
+
+ status = wait_lwp (lp);
+ if (status == 0)
+ return 0;
+
+ /* Ignore any signals in FLUSH_MASK. */
+ if (flush_mask && sigismember (flush_mask, WSTOPSIG (status)))
+ {
+ if (!lp->signalled)
+ {
+ lp->stopped = 1;
+ return 0;
+ }
+
+ errno = 0;
+ ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "PTRACE_CONT %s, 0, 0 (%s)\n",
+ target_pid_to_str (lp->ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ return stop_wait_callback (lp, flush_mask);
+ }
+
+ if (WSTOPSIG (status) != SIGSTOP)
+ {
+ if (WSTOPSIG (status) == SIGTRAP)
+ {
+ /* 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. */
+
+ /* 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 the SIGTRAP for handling by linux_nat_wait. */
+ stop_wait_callback (lp, data);
+ /* If there's another event, throw it back into the queue. */
+ if (lp->status)
+ {
+ 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, data);
+ /* If the lp->status field is still empty, use it to hold
+ this event. If not, then this event must be returned
+ to the event queue of the LWP. */
+ if (lp->status == 0)
+ lp->status = status;
+ else
+ {
+ if (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));
+ }
+ 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;
+}
+
+/* Check whether PID has any pending signals in FLUSH_MASK. If so set
+ the appropriate bits in PENDING, and return 1 - otherwise return 0. */
+
+static int
+linux_nat_has_pending (int pid, sigset_t *pending, sigset_t *flush_mask)
+{
+ sigset_t blocked, ignored;
+ int i;
+
+ linux_proc_pending_signals (pid, pending, &blocked, &ignored);
+
+ if (!flush_mask)
+ return 0;
+
+ for (i = 1; i < NSIG; i++)
+ if (sigismember (pending, i))
+ if (!sigismember (flush_mask, i)
+ || sigismember (&blocked, i)
+ || sigismember (&ignored, i))
+ sigdelset (pending, i);
+
+ if (sigisemptyset (pending))
+ return 0;
+
+ return 1;
+}
+
+/* DATA is interpreted as a mask of signals to flush. If LP has
+ signals pending, and they are all in the flush mask, then arrange
+ to flush them. LP should be stopped, as should all other threads
+ it might share a signal queue with. */
+
+static int
+flush_callback (struct lwp_info *lp, void *data)
+{
+ sigset_t *flush_mask = data;
+ sigset_t pending, intersection, blocked, ignored;
+ int pid, status;
+
+ /* Normally, when an LWP exits, it is removed from the LWP list. The
+ last LWP isn't removed till later, however. So if there is only
+ one LWP on the list, make sure it's alive. */
+ if (lwp_list == lp && lp->next == NULL)
+ if (!linux_nat_thread_alive (lp->ptid))
+ return 0;
+
+ /* Just because the LWP is stopped doesn't mean that new signals
+ can't arrive from outside, so this function must be careful of
+ race conditions. However, because all threads are stopped, we
+ can assume that the pending mask will not shrink unless we resume
+ the LWP, and that it will then get another signal. We can't
+ control which one, however. */
+
+ if (lp->status)
+ {
+ if (debug_linux_nat)
+ printf_unfiltered (_("FC: LP has pending status %06x\n"), lp->status);
+ if (WIFSTOPPED (lp->status) && sigismember (flush_mask, WSTOPSIG (lp->status)))
+ lp->status = 0;
+ }
+
+ /* While there is a pending signal we would like to flush, continue
+ the inferior and collect another signal. But if there's already
+ a saved status that we don't want to flush, we can't resume the
+ inferior - if it stopped for some other reason we wouldn't have
+ anywhere to save the new status. In that case, we must leave the
+ signal unflushed (and possibly generate an extra SIGINT stop).
+ That's much less bad than losing a signal. */
+ while (lp->status == 0
+ && linux_nat_has_pending (GET_LWP (lp->ptid), &pending, flush_mask))
+ {
+ int ret;
+
+ errno = 0;
+ ret = ptrace (PTRACE_CONT, GET_LWP (lp->ptid), 0, 0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stderr,
+ "FC: Sent PTRACE_CONT, ret %d %d\n", ret, errno);
+
+ lp->stopped = 0;
+ stop_wait_callback (lp, flush_mask);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stderr,
+ "FC: Wait finished; saved status is %d\n",
+ lp->status);
+ }
+
+ return 0;
+}
+
+/* Return non-zero if LP has a wait status pending. */
+
+static int
+status_callback (struct lwp_info *lp, void *data)
+{
+ /* Only report a pending wait status if we pretend that this has
+ indeed been resumed. */
+ return (lp->status != 0 && lp->resumed);
+}
+
+/* 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 LWPs that have a SIGTRAP event pending. */
+ if (lp->status != 0
+ && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP)
+ (*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 LWPs that have a SIGTRAP event pending. */
+ if (lp->status != 0
+ && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP)
+ if ((*selector)-- == 0)
+ return 1;
+
+ return 0;
+}
+
+static int
+cancel_breakpoints_callback (struct lwp_info *lp, void *data)
+{
+ struct lwp_info *event_lp = data;
+
+ /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
+ if (lp == event_lp)
+ return 0;
+
+ /* If a LWP other than the LWP that we're reporting an event for has
+ hit a GDB breakpoint (as opposed to some random trap signal),
+ then just arrange for it to hit it again later. We don't keep
+ the SIGTRAP status and don't forward the SIGTRAP signal to the
+ LWP. We will handle the current event, eventually we will resume
+ all LWPs, and this one will get its breakpoint trap again.
+
+ If we do not do this, then we run the risk that the user will
+ delete or disable the breakpoint, but the LWP will have already
+ tripped on it. */
+
+ if (lp->status != 0
+ && WIFSTOPPED (lp->status) && WSTOPSIG (lp->status) == SIGTRAP
+ && breakpoint_inserted_here_p (read_pc_pid (lp->ptid) -
+ gdbarch_decr_pc_after_break
+ (current_gdbarch)))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "CBC: Push back breakpoint for %s\n",
+ target_pid_to_str (lp->ptid));
+
+ /* Back up the PC if necessary. */
+ if (gdbarch_decr_pc_after_break (current_gdbarch))
+ write_pc_pid (read_pc_pid (lp->ptid) - gdbarch_decr_pc_after_break
+ (current_gdbarch),
+ lp->ptid);
+
+ /* Throw away the SIGTRAP. */
+ lp->status = 0;
+ }
+
+ return 0;
+}
+
+/* Select one LWP out of those that have events pending. */
+
+static void
+select_event_lwp (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 (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 (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 (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;
+}
+
+static ptid_t
+linux_nat_wait (ptid_t ptid, struct target_waitstatus *ourstatus)
+{
+ struct lwp_info *lp = NULL;
+ int options = 0;
+ int status = 0;
+ pid_t pid = PIDGET (ptid);
+ sigset_t flush_mask;
+
+ /* The first time we get here after starting a new inferior, we may
+ not have added it to the LWP list yet - this is the earliest
+ moment at which we know its PID. */
+ if (num_lwps == 0)
+ {
+ gdb_assert (!is_lwp (inferior_ptid));
+
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ lp = add_lwp (inferior_ptid);
+ lp->resumed = 1;
+ }
+
+ sigemptyset (&flush_mask);
+
+ /* Make sure SIGCHLD is blocked. */
+ if (!sigismember (&blocked_mask, SIGCHLD))
+ {
+ sigaddset (&blocked_mask, SIGCHLD);
+ sigprocmask (SIG_BLOCK, &blocked_mask, NULL);
+ }
+
+retry:
+
+ /* Make sure there is at least one LWP that has been resumed. */
+ gdb_assert (iterate_over_lwps (resumed_callback, NULL));
+
+ /* First check if there is a LWP with a wait status pending. */
+ if (pid == -1)
+ {
+ /* Any LWP that's been resumed will do. */
+ lp = iterate_over_lwps (status_callback, NULL);
+ if (lp)
+ {
+ status = lp->status;
+ lp->status = 0;
+
+ if (debug_linux_nat && status)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Using pending wait status %s for %s.\n",
+ status_to_str (status),
+ target_pid_to_str (lp->ptid));
+ }
+
+ /* But if we don't fine 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);
+ status = lp->status;
+ lp->status = 0;
+
+ if (debug_linux_nat && status)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Using pending wait status %s for %s.\n",
+ status_to_str (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);
+ }
+
+ if (status && 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 (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);
+
+ /* This should catch the pending SIGSTOP. */
+ stop_wait_callback (lp, NULL);
+ }
+
+ set_sigint_trap (); /* Causes SIGINT to be passed on to the
+ attached process. */
+ set_sigio_trap ();
+
+ while (status == 0)
+ {
+ 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 = find_lwp_pid (pid_to_ptid (lwpid));
+
+ /* Check for stop events reported by a process we didn't
+ already know about - anything not already in our LWP
+ list.
+
+ If we're expecting to receive stopped processes after
+ fork, vfork, and clone events, then we'll just add the
+ new one to our list and go back to waiting for the event
+ to be reported - the stopped process might be returned
+ from waitpid before or after the event is. */
+ if (WIFSTOPPED (status) && !lp)
+ {
+ linux_record_stopped_pid (lwpid, status);
+ status = 0;
+ continue;
+ }
+
+ /* Make sure we don't report an event for the exit of an LWP not in
+ our list, i.e. not part of the current process. This can happen
+ if we detach from a program we original forked and then it
+ exits. */
+ if (!WIFSTOPPED (status) && !lp)
+ {
+ status = 0;
+ continue;
+ }
+
+ /* NOTE drow/2003-06-17: This code seems to be meant for debugging
+ CLONE_PTRACE processes which do not use the thread library -
+ otherwise we wouldn't find the new LWP this way. That doesn't
+ currently work, and the following code is currently unreachable
+ due to the two blocks above. If it's fixed some day, this code
+ should be broken out into a function so that we can also pick up
+ LWPs from the new interface. */
+ if (!lp)
+ {
+ lp = add_lwp (BUILD_LWP (lwpid, GET_PID (inferior_ptid)));
+ if (options & __WCLONE)
+ lp->cloned = 1;
+
+ gdb_assert (WIFSTOPPED (status)
+ && WSTOPSIG (status) == SIGSTOP);
+ lp->signalled = 1;
+
+ if (!in_thread_list (inferior_ptid))
+ {
+ inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid),
+ GET_PID (inferior_ptid));
+ add_thread (inferior_ptid);
+ }
+
+ add_thread (lp->ptid);
+ printf_unfiltered (_("[New %s]\n"),
+ target_pid_to_str (lp->ptid));
+ }
+
+ /* Handle GNU/Linux's extended waitstatus for trace events. */
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Handling extended status 0x%06x\n",
+ status);
+ if (linux_handle_extended_wait (lp, status, 0))
+ {
+ status = 0;
+ continue;
+ }
+ }
+
+ /* Check if the thread has exited. */
+ if ((WIFEXITED (status) || WIFSIGNALED (status)) && num_lwps > 1)
+ {
+ /* If this is the main thread, we must stop all threads and
+ verify if they are still alive. This is because in the nptl
+ thread model, there is no signal issued for exiting LWPs
+ other than the main thread. We only get the main thread
+ exit signal once all child threads have already exited.
+ If we stop all the threads and use the stop_wait_callback
+ to check if they have exited we can determine whether this
+ signal should be ignored or whether it means the end of the
+ debugged application, regardless of which threading model
+ is being used. */
+ if (GET_PID (lp->ptid) == GET_LWP (lp->ptid))
+ {
+ lp->stopped = 1;
+ iterate_over_lwps (stop_and_resume_callback, NULL);
+ }
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
+
+ /* If there is at least one more LWP, then the exit signal
+ was not the end of the debugged application and should be
+ ignored. */
+ if (num_lwps > 0)
+ {
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (running_callback, NULL));
+
+ /* Discard the event. */
+ status = 0;
+ continue;
+ }
+ }
+
+ /* Check if the current LWP has previously exited. In the nptl
+ thread model, LWPs other than the main thread do not issue
+ signals when they exit so we must check whenever the thread
+ has stopped. A similar check is made in stop_wait_callback(). */
+ if (num_lwps > 1 && !linux_nat_thread_alive (lp->ptid))
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s exited.\n",
+ target_pid_to_str (lp->ptid));
+
+ exit_lwp (lp);
+
+ /* Make sure there is at least one thread running. */
+ gdb_assert (iterate_over_lwps (running_callback, NULL));
+
+ /* Discard the event. */
+ status = 0;
+ continue;
+ }
+
+ /* Make sure we don't report a SIGSTOP that we sent
+ ourselves in an attempt to stop an LWP. */
+ if (lp->signalled
+ && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP)
+ {
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: Delayed SIGSTOP caught for %s.\n",
+ target_pid_to_str (lp->ptid));
+
+ /* This is a delayed SIGSTOP. */
+ lp->signalled = 0;
+
+ registers_changed ();
+ linux_ops->to_resume (pid_to_ptid (GET_LWP (lp->ptid)),
+ lp->step, TARGET_SIGNAL_0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: %s %s, 0, 0 (discard SIGSTOP)\n",
+ lp->step ?
+ "PTRACE_SINGLESTEP" : "PTRACE_CONT",
+ target_pid_to_str (lp->ptid));
+
+ lp->stopped = 0;
+ gdb_assert (lp->resumed);
+
+ /* Discard the event. */
+ status = 0;
+ continue;
+ }
+
+ break;
+ }
+
+ if (pid == -1)
+ {
+ /* Alternate between checking cloned and uncloned processes. */
+ options ^= __WCLONE;
+
+ /* And suspend every time we have checked both. */
+ if (options & __WCLONE)
+ sigsuspend (&suspend_mask);
+ }
+
+ /* We shouldn't end up here unless we want to try again. */
+ gdb_assert (status == 0);
+ }
+
+ clear_sigio_trap ();
+ clear_sigint_trap ();
+
+ gdb_assert (lp);
+
+ /* 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))
+ {
+ int signo = target_signal_from_host (WSTOPSIG (status));
+
+ /* If we get a signal while single-stepping, we may need special
+ care, e.g. to skip the signal handler. Defer to common code. */
+ if (!lp->step
+ && signal_stop_state (signo) == 0
+ && signal_print_state (signo) == 0
+ && signal_pass_state (signo) == 1)
+ {
+ /* 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 (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 ? strsignal (signo) : "0");
+ lp->stopped = 0;
+ status = 0;
+ goto retry;
+ }
+
+ 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 LWP's
+ will receive it. Since we only want to report it once,
+ we try to flush it from all LWPs except this one. */
+ sigaddset (&flush_mask, SIGINT);
+ }
+ }
+
+ /* 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));
+
+ /* Now stop all other LWP's ... */
+ iterate_over_lwps (stop_callback, NULL);
+
+ /* ... and wait until all of them have reported back that they're no
+ longer running. */
+ iterate_over_lwps (stop_wait_callback, &flush_mask);
+ iterate_over_lwps (flush_callback, &flush_mask);
+
+ /* If we're not waiting for a specific LWP, choose an event LWP from
+ among those that have had events. Giving equal priority to all
+ LWPs that have had events helps prevent starvation. */
+ if (pid == -1)
+ select_event_lwp (&lp, &status);
+
+ /* Now that we've selected our final event LWP, cancel any
+ breakpoints in other LWPs that have hit a GDB breakpoint. See
+ the comment in cancel_breakpoints_callback to find out why. */
+ iterate_over_lwps (cancel_breakpoints_callback, lp);
+
+ if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP)
+ {
+ trap_ptid = lp->ptid;
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLW: trap_ptid is %s.\n",
+ target_pid_to_str (trap_ptid));
+ }
+ else
+ trap_ptid = null_ptid;
+
+ if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE)
+ {
+ *ourstatus = lp->waitstatus;
+ lp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
+ }
+ else
+ store_waitstatus (ourstatus, status);
+
+ return lp->ptid;
+}
+
+static int
+kill_callback (struct lwp_info *lp, void *data)
+{
+ 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 && debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "KWC: wait %s received unknown.\n",
+ target_pid_to_str (lp->ptid));
+ }
+ }
+ 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 && debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "KWC: wait %s received unk.\n",
+ target_pid_to_str (lp->ptid));
+ }
+ }
+ while (pid == GET_LWP (lp->ptid));
+
+ gdb_assert (pid == -1 && errno == ECHILD);
+ return 0;
+}
+
+static void
+linux_nat_kill (void)
+{
+ 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)
+ {
+ ptrace (PT_KILL, last.value.related_pid, 0, 0);
+ wait (&status);
+ }
+
+ if (forks_exist_p ())
+ linux_fork_killall ();
+ else
+ {
+ /* Kill all LWP's ... */
+ iterate_over_lwps (kill_callback, NULL);
+
+ /* ... and wait until we've flushed all events. */
+ iterate_over_lwps (kill_wait_callback, NULL);
+ }
+
+ target_mourn_inferior ();
+}
+
+static void
+linux_nat_mourn_inferior (void)
+{
+ trap_ptid = null_ptid;
+
+ /* Destroy LWP info; it's no longer valid. */
+ init_lwp_list ();
+
+ /* Restore the original signal mask. */
+ sigprocmask (SIG_SETMASK, &normal_mask, NULL);
+ sigemptyset (&blocked_mask);
+
+ if (! forks_exist_p ())
+ /* Normal case, no other forks available. */
+ linux_ops->to_mourn_inferior ();
+ else
+ /* Multi-fork case. The current inferior_ptid has exited, but
+ there are other viable forks to debug. Delete the exiting
+ one and context-switch to the first available. */
+ linux_fork_mourn_inferior ();
+}
+
+static LONGEST
+linux_nat_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf,
+ ULONGEST offset, LONGEST len)
+{
+ struct cleanup *old_chain = save_inferior_ptid ();
+ LONGEST xfer;
+
+ 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_nat_thread_alive (ptid_t ptid)
+{
+ gdb_assert (is_lwp (ptid));
+
+ errno = 0;
+ ptrace (PTRACE_PEEKUSER, GET_LWP (ptid), 0, 0);
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLTA: PTRACE_PEEKUSER %s, 0, 0 (%s)\n",
+ target_pid_to_str (ptid),
+ errno ? safe_strerror (errno) : "OK");
+
+ /* Not every Linux kernel implements PTRACE_PEEKUSER. But we can
+ handle that case gracefully since ptrace will first do a lookup
+ for the process based upon the passed-in pid. If that fails we
+ will get either -ESRCH or -EPERM, otherwise the child exists and
+ is alive. */
+ if (errno == ESRCH || errno == EPERM)
+ return 0;
+
+ return 1;
+}
+
+static char *
+linux_nat_pid_to_str (ptid_t ptid)
+{
+ static char buf[64];
+
+ if (lwp_list && lwp_list->next && is_lwp (ptid))
+ {
+ snprintf (buf, sizeof (buf), "LWP %ld", GET_LWP (ptid));
+ return buf;
+ }
+
+ return normal_pid_to_str (ptid);
+}
+
+static void
+sigchld_handler (int signo)
+{
+ /* Do nothing. The only reason for this handler is that it allows
+ us to use sigsuspend in linux_nat_wait above to wait for the
+ arrival of a SIGCHLD. */
+}
+
+/* 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 (int (*func) (CORE_ADDR,
+ unsigned long,
+ int, int, int, void *), void *obfd)
+{
+ long long pid = PIDGET (inferior_ptid);
+ char mapsfilename[MAXPATHLEN];
+ FILE *mapsfile;
+ long long addr, endaddr, size, offset, inode;
+ char permissions[8], device[8], filename[MAXPATHLEN];
+ int read, write, exec;
+ int ret;
+
+ /* Compose the filename for the /proc memory map, and open it. */
+ sprintf (mapsfilename, "/proc/%lld/maps", pid);
+ if ((mapsfile = fopen (mapsfilename, "r")) == NULL)
+ error (_("Could not open %s."), mapsfilename);
+
+ 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, %lld bytes at 0x%s (%c%c%c)",
+ size, paddr_nz (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);
+ }
+ fclose (mapsfile);
+ return 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)
+{
+ gdb_gregset_t gregs;
+ gdb_fpregset_t fpregs;
+#ifdef FILL_FPXREGSET
+ gdb_fpxregset_t fpxregs;
+#endif
+ unsigned long lwp = ptid_get_lwp (ptid);
+ struct regcache *regcache = get_thread_regcache (ptid);
+ struct gdbarch *gdbarch = get_regcache_arch (regcache);
+ const struct regset *regset;
+ int core_regset_p;
+ struct cleanup *old_chain;
+
+ old_chain = save_inferior_ptid ();
+ inferior_ptid = ptid;
+ target_fetch_registers (regcache, -1);
+ do_cleanups (old_chain);
+
+ core_regset_p = gdbarch_regset_from_core_section_p (gdbarch);
+ if (core_regset_p
+ && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg",
+ sizeof (gregs))) != NULL
+ && regset->collect_regset != NULL)
+ regset->collect_regset (regset, regcache, -1,
+ &gregs, sizeof (gregs));
+ else
+ fill_gregset (regcache, &gregs, -1);
+
+ note_data = (char *) elfcore_write_prstatus (obfd,
+ note_data,
+ note_size,
+ lwp,
+ stop_signal, &gregs);
+
+ if (core_regset_p
+ && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2",
+ sizeof (fpregs))) != NULL
+ && regset->collect_regset != NULL)
+ regset->collect_regset (regset, regcache, -1,
+ &fpregs, sizeof (fpregs));
+ else
+ fill_fpregset (regcache, &fpregs, -1);
+
+ note_data = (char *) elfcore_write_prfpreg (obfd,
+ note_data,
+ note_size,
+ &fpregs, sizeof (fpregs));
+
+#ifdef FILL_FPXREGSET
+ if (core_regset_p
+ && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg-xfp",
+ sizeof (fpxregs))) != NULL
+ && regset->collect_regset != NULL)
+ regset->collect_regset (regset, regcache, -1,
+ &fpxregs, sizeof (fpxregs));
+ else
+ fill_fpxregset (regcache, &fpxregs, -1);
+
+ note_data = (char *) elfcore_write_prxfpreg (obfd,
+ note_data,
+ note_size,
+ &fpxregs, sizeof (fpxregs));
+#endif
+ return note_data;
+}
+
+struct linux_nat_corefile_thread_data
+{
+ bfd *obfd;
+ char *note_data;
+ int *note_size;
+ int num_notes;
+};
+
+/* 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->num_notes++;
+
+ return 0;
+}
+
+/* Records the register state for the corefile note section. */
+
+static char *
+linux_nat_do_registers (bfd *obfd, ptid_t ptid,
+ char *note_data, int *note_size)
+{
+ return linux_nat_do_thread_registers (obfd,
+ ptid_build (ptid_get_pid (inferior_ptid),
+ ptid_get_pid (inferior_ptid),
+ 0),
+ note_data, note_size);
+}
+
+/* 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;
+ struct cleanup *old_chain;
+ /* The variable size must be >= sizeof (prpsinfo_t.pr_fname). */
+ char fname[16] = { '\0' };
+ /* The variable size must be >= sizeof (prpsinfo_t.pr_psargs). */
+ char psargs[80] = { '\0' };
+ char *note_data = NULL;
+ ptid_t current_ptid = inferior_ptid;
+ gdb_byte *auxv;
+ int auxv_len;
+
+ if (get_exec_file (0))
+ {
+ strncpy (fname, strrchr (get_exec_file (0), '/') + 1, 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;
+ iterate_over_lwps (linux_nat_corefile_thread_callback, &thread_args);
+ if (thread_args.num_notes == 0)
+ {
+ /* iterate_over_threads didn't come up with any threads; just
+ use inferior_ptid. */
+ note_data = linux_nat_do_registers (obfd, inferior_ptid,
+ note_data, note_size);
+ }
+ else
+ {
+ note_data = thread_args.note_data;
+ }
+
+ 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);
+ }
+
+ 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)
+{
+ long 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 environ_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. */
+ if ((argv = buildargv (args)) == NULL)
+ nomem (0);
+ else
+ 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/%lld", pid);
+ if (stat (fname1, &dummy) != 0)
+ error (_("No /proc directory: '%s'"), fname1);
+
+ printf_filtered (_("process %lld\n"), pid);
+ if (cmdline_f || all)
+ {
+ sprintf (fname1, "/proc/%lld/cmdline", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ fgets (buffer, sizeof (buffer), procfile);
+ printf_filtered ("cmdline = '%s'\n", buffer);
+ fclose (procfile);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+ if (cwd_f || all)
+ {
+ sprintf (fname1, "/proc/%lld/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/%lld/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/%lld/maps", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ long long addr, endaddr, size, offset, inode;
+ char permissions[8], device[8], filename[MAXPATHLEN];
+
+ printf_filtered (_("Mapped address spaces:\n\n"));
+ if (gdbarch_addr_bit (current_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 (current_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 : "");
+ }
+ }
+
+ fclose (procfile);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+ if (status_f || all)
+ {
+ sprintf (fname1, "/proc/%lld/status", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ while (fgets (buffer, sizeof (buffer), procfile) != NULL)
+ puts_filtered (buffer);
+ fclose (procfile);
+ }
+ else
+ warning (_("unable to open /proc file '%s'"), fname1);
+ }
+ if (stat_f || all)
+ {
+ sprintf (fname1, "/proc/%lld/stat", pid);
+ if ((procfile = fopen (fname1, "r")) != NULL)
+ {
+ int itmp;
+ char ctmp;
+ long ltmp;
+
+ if (fscanf (procfile, "%d ", &itmp) > 0)
+ printf_filtered (_("Process: %d\n"), itmp);
+ if (fscanf (procfile, "(%[^)]) ", &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
+ fclose (procfile);
+ }
+ 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;
+}
+
+/* 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];
+ int signum;
+
+ 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);
+
+ 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);
+ }
+
+ fclose (procfile);
+}
+
+static LONGEST
+linux_xfer_partial (struct target_ops *ops, enum target_object object,
+ const char *annex, gdb_byte *readbuf,
+ const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
+{
+ LONGEST xfer;
+
+ if (object == TARGET_OBJECT_AUXV)
+ return procfs_xfer_auxv (ops, object, annex, readbuf, writebuf,
+ offset, len);
+
+ xfer = linux_proc_xfer_partial (ops, object, annex, readbuf, writebuf,
+ offset, len);
+ if (xfer != 0)
+ return xfer;
+
+ return super_xfer_partial (ops, object, annex, readbuf, writebuf,
+ offset, len);
+}
+
+/* Create a prototype generic Linux target. The client can override
+ it with local methods. */
+
+static void
+linux_target_install_ops (struct target_ops *t)
+{
+ t->to_insert_fork_catchpoint = linux_child_insert_fork_catchpoint;
+ t->to_insert_vfork_catchpoint = linux_child_insert_vfork_catchpoint;
+ t->to_insert_exec_catchpoint = linux_child_insert_exec_catchpoint;
+ t->to_pid_to_exec_file = linux_child_pid_to_exec_file;
+ t->to_post_startup_inferior = linux_child_post_startup_inferior;
+ t->to_post_attach = linux_child_post_attach;
+ t->to_follow_fork = linux_child_follow_fork;
+ t->to_find_memory_regions = linux_nat_find_memory_regions;
+ t->to_make_corefile_notes = linux_nat_make_corefile_notes;
+
+ super_xfer_partial = t->to_xfer_partial;
+ t->to_xfer_partial = linux_xfer_partial;
+}
+
+struct target_ops *
+linux_target (void)
+{
+ struct target_ops *t;
+
+ t = inf_ptrace_target ();
+ linux_target_install_ops (t);
+
+ return t;
+}
+
+struct target_ops *
+linux_trad_target (CORE_ADDR (*register_u_offset)(struct gdbarch *, int, int))
+{
+ struct target_ops *t;
+
+ t = inf_ptrace_trad_target (register_u_offset);
+ linux_target_install_ops (t);
+
+ return t;
+}
+
+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_attach = linux_nat_attach;
+ t->to_detach = linux_nat_detach;
+ t->to_resume = linux_nat_resume;
+ t->to_wait = linux_nat_wait;
+ t->to_xfer_partial = linux_nat_xfer_partial;
+ t->to_kill = linux_nat_kill;
+ t->to_mourn_inferior = linux_nat_mourn_inferior;
+ t->to_thread_alive = linux_nat_thread_alive;
+ t->to_pid_to_str = linux_nat_pid_to_str;
+ t->to_has_thread_control = tc_schedlock;
+
+ /* We don't change the stratum; this target will sit at
+ process_stratum and thread_db will set at thread_stratum. This
+ is a little strange, since this is a multi-threaded-capable
+ target, but we want to be on the stack below thread_db, and we
+ also want to be used for single-threaded processes. */
+
+ add_target (t);
+
+ /* TODO: Eliminate this and have libthread_db use
+ find_target_beneath. */
+ thread_db_init (t);
+}
+
+void
+_initialize_linux_nat (void)
+{
+ struct sigaction action;
+
+ 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."));
+
+ /* Save the original signal mask. */
+ sigprocmask (SIG_SETMASK, NULL, &normal_mask);
+
+ action.sa_handler = sigchld_handler;
+ sigemptyset (&action.sa_mask);
+ action.sa_flags = SA_RESTART;
+ sigaction (SIGCHLD, &action, NULL);
+
+ /* Make sure we don't block SIGCHLD during a sigsuspend. */
+ sigprocmask (SIG_SETMASK, NULL, &suspend_mask);
+ sigdelset (&suspend_mask, SIGCHLD);
+
+ sigemptyset (&blocked_mask);
+
+ add_setshow_zinteger_cmd ("lin-lwp", no_class, &debug_linux_nat, _("\
+Set debugging of GNU/Linux lwp module."), _("\
+Show debugging of GNU/Linux lwp module."), _("\
+Enables printf debugging output."),
+ NULL,
+ show_debug_linux_nat,
+ &setdebuglist, &showdebuglist);
+}
+\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 (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