/* GNU/Linux native-dependent code for debugging multiple forks.
- Copyright (C) 2005, 2006 Free Software Foundation, Inc.
+ Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010
+ 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., 51 Franklin Street, Fifth Floor,
- Boston, MA 02110-1301, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
+#include "arch-utils.h"
#include "inferior.h"
#include "regcache.h"
#include "gdbcmd.h"
#include "infcall.h"
+#include "objfiles.h"
#include "gdb_assert.h"
#include "gdb_string.h"
#include "linux-fork.h"
#include "linux-nat.h"
+#include "gdbthread.h"
#include <sys/ptrace.h>
-#include <sys/wait.h>
+#include "gdb_wait.h"
#include <sys/param.h>
-#include <dirent.h>
+#include "gdb_dirent.h"
#include <ctype.h>
struct fork_info *fork_list;
/* Prevent warning from -Wmissing-prototypes. */
extern void _initialize_linux_fork (void);
-int detach_fork = 1; /* Default behavior is to detach
- newly forked processes (legacy). */
-
/* Fork list data structure: */
struct fork_info
{
struct fork_info *next;
ptid_t ptid;
+ ptid_t parent_ptid;
int num; /* Convenient handle (GDB fork id) */
- struct regcache *savedregs; /* Convenient for info fork, saves
+ struct regcache *savedregs; /* Convenient for info fork, saves
having to actually switch contexts. */
int clobber_regs; /* True if we should restore saved regs. */
- ULONGEST pc; /* PC for info fork. */
off_t *filepos; /* Set of open file descriptors' offsets. */
int maxfd;
};
/* Fork list methods: */
-extern int
+int
forks_exist_p (void)
{
return (fork_list != NULL);
}
-/* Add a fork to internal fork list.
- Called from linux child_follow_fork. */
+/* Add a fork to the internal fork list. */
-extern struct fork_info *
+struct fork_info *
add_fork (pid_t pid)
{
struct fork_info *fp;
free_fork (fp);
- /* Special case: if there is now only one process in the list,
+ /* Special case: if there is now only one process in the list,
and if it is (hopefully!) the current inferior_ptid, then
remove it, leaving the list empty -- we're now down to the
default case of debugging a single process. */
/* Fork list <-> gdb interface. */
-/* Utility function for fork_load/fork_save.
+/* Utility function for fork_load/fork_save.
Calls lseek in the (current) inferior process. */
static off_t
extern void nullify_last_target_wait_ptid ();
int i;
- inferior_ptid = fp->ptid;
-
- linux_nat_switch_fork (inferior_ptid);
+ linux_nat_switch_fork (fp->ptid);
if (fp->savedregs && fp->clobber_regs)
- regcache_cpy (current_regcache, fp->savedregs);
+ regcache_cpy (get_current_regcache (), fp->savedregs);
registers_changed ();
reinit_frame_cache ();
- /* We must select a new frame before making any inferior calls to
- avoid warnings. */
- select_frame (get_current_frame ());
-
- stop_pc = read_pc ();
+ stop_pc = regcache_read_pc (get_current_regcache ());
nullify_last_target_wait_ptid ();
/* Now restore the file positions of open file descriptors. */
/* Save infrun state for the fork PTID.
Exported for use by linux child_follow_fork. */
-extern void
+static void
fork_save_infrun_state (struct fork_info *fp, int clobber_regs)
{
char path[MAXPATHLEN];
if (fp->savedregs)
regcache_xfree (fp->savedregs);
- fp->savedregs = regcache_dup (current_regcache);
+ fp->savedregs = regcache_dup (get_current_regcache ());
fp->clobber_regs = clobber_regs;
- fp->pc = read_pc ();
if (clobber_regs)
{
fp->maxfd = tmp;
}
/* Allocate array of file positions. */
- fp->filepos = xrealloc (fp->filepos,
+ fp->filepos = xrealloc (fp->filepos,
(fp->maxfd + 1) * sizeof (*fp->filepos));
/* Initialize to -1 (invalid). */
/* Kill 'em all, let God sort 'em out... */
-extern void
+void
linux_fork_killall (void)
{
/* Walk list and kill every pid. No need to treat the
{
pid = PIDGET (fp->ptid);
do {
- ptrace (PT_KILL, pid, 0, 0);
+ /* Use SIGKILL instead of PTRACE_KILL because the former works even
+ if the thread is running, while the later doesn't. */
+ kill (pid, SIGKILL);
ret = waitpid (pid, &status, 0);
/* We might get a SIGCHLD instead of an exit status. This is
aggravated by the first kill above - a child has just
forks to debug. Delete the exiting one and context-switch to the
first available. */
-extern void
+void
linux_fork_mourn_inferior (void)
{
/* Wait just one more time to collect the inferior's exit status.
delete_fork (inferior_ptid);
}
+/* The current inferior_ptid is being detached, but there are other
+ viable forks to debug. Detach and delete it and context-switch to
+ the first available. */
+
+void
+linux_fork_detach (char *args, int from_tty)
+{
+ /* OK, inferior_ptid is the one we are detaching from. We need to
+ delete it from the fork_list, and switch to the next available
+ fork. */
+
+ if (ptrace (PTRACE_DETACH, PIDGET (inferior_ptid), 0, 0))
+ error (_("Unable to detach %s"), target_pid_to_str (inferior_ptid));
+
+ delete_fork (inferior_ptid);
+
+ /* There should still be a fork - if there's only one left,
+ delete_fork won't remove it, because we haven't updated
+ inferior_ptid yet. */
+ gdb_assert (fork_list);
+
+ fork_load_infrun_state (fork_list);
+
+ if (from_tty)
+ printf_filtered (_("[Switching to %s]\n"),
+ target_pid_to_str (inferior_ptid));
+
+ /* If there's only one fork, switch back to non-fork mode. */
+ if (fork_list->next == NULL)
+ delete_fork (inferior_ptid);
+}
+
+static void
+inferior_call_waitpid_cleanup (void *fp)
+{
+ struct fork_info *oldfp = fp;
+
+ if (oldfp)
+ {
+ /* Switch back to inferior_ptid. */
+ remove_breakpoints ();
+ fork_load_infrun_state (oldfp);
+ insert_breakpoints ();
+ }
+}
+
+static int
+inferior_call_waitpid (ptid_t pptid, int pid)
+{
+ struct objfile *waitpid_objf;
+ struct value *waitpid_fn = NULL;
+ struct value *argv[4], *retv;
+ struct gdbarch *gdbarch = get_current_arch ();
+ struct fork_info *oldfp = NULL, *newfp = NULL;
+ struct cleanup *old_cleanup;
+ int ret = -1;
+
+ if (!ptid_equal (pptid, inferior_ptid))
+ {
+ /* Switch to pptid. */
+ oldfp = find_fork_ptid (inferior_ptid);
+ gdb_assert (oldfp != NULL);
+ newfp = find_fork_ptid (pptid);
+ gdb_assert (oldfp != NULL);
+ fork_save_infrun_state (oldfp, 1);
+ remove_breakpoints ();
+ fork_load_infrun_state (newfp);
+ insert_breakpoints ();
+ }
+
+ old_cleanup = make_cleanup (inferior_call_waitpid_cleanup, oldfp);
+
+ /* Get the waitpid_fn. */
+ if (lookup_minimal_symbol ("waitpid", NULL, NULL) != NULL)
+ waitpid_fn = find_function_in_inferior ("waitpid", &waitpid_objf);
+ if (!waitpid_fn && lookup_minimal_symbol ("_waitpid", NULL, NULL) != NULL)
+ waitpid_fn = find_function_in_inferior ("_waitpid", &waitpid_objf);
+ if (!waitpid_fn)
+ goto out;
+
+ /* Get the argv. */
+ argv[0] = value_from_longest (builtin_type (gdbarch)->builtin_int, pid);
+ argv[1] = value_from_pointer (builtin_type (gdbarch)->builtin_data_ptr, 0);
+ argv[2] = value_from_longest (builtin_type (gdbarch)->builtin_int, 0);
+ argv[3] = 0;
+
+ retv = call_function_by_hand (waitpid_fn, 3, argv);
+ if (value_as_long (retv) < 0)
+ goto out;
+
+ ret = 0;
+
+out:
+ do_cleanups (old_cleanup);
+ return ret;
+}
+
/* Fork list <-> user interface. */
static void
-delete_fork_command (char *args, int from_tty)
+delete_checkpoint_command (char *args, int from_tty)
{
- ptid_t ptid;
+ ptid_t ptid, pptid;
+ struct fork_info *fi;
if (!args || !*args)
- error (_("Requires argument (fork/checkpoint id to delete)"));
+ error (_("Requires argument (checkpoint id to delete)"));
ptid = fork_id_to_ptid (parse_and_eval_long (args));
if (ptid_equal (ptid, minus_one_ptid))
- error (_("No such fork/checkpoint id, %s"), args);
+ error (_("No such checkpoint id, %s"), args);
if (ptid_equal (ptid, inferior_ptid))
- error (_("Please switch to another fork/checkpoint before deleting the current one"));
+ error (_("\
+Please switch to another checkpoint before deleting the current one"));
if (ptrace (PTRACE_KILL, PIDGET (ptid), 0, 0))
- error (_("Unable to kill pid %s"), target_tid_to_str (ptid));
+ error (_("Unable to kill pid %s"), target_pid_to_str (ptid));
+
+ fi = find_fork_ptid (ptid);
+ gdb_assert (fi);
+ pptid = fi->parent_ptid;
if (from_tty)
printf_filtered (_("Killed %s\n"), target_pid_to_str (ptid));
delete_fork (ptid);
+
+ /* If fi->parent_ptid is not a part of lwp but it's a part of checkpoint
+ list, waitpid the ptid.
+ If fi->parent_ptid is a part of lwp and it is stoped, waitpid the
+ ptid. */
+ if ((!find_thread_ptid (pptid) && find_fork_ptid (pptid))
+ || (find_thread_ptid (pptid) && is_stopped (pptid)))
+ {
+ if (inferior_call_waitpid (pptid, PIDGET (ptid)))
+ warning (_("Unable to wait pid %s"), target_pid_to_str (ptid));
+ }
}
static void
-detach_fork_command (char *args, int from_tty)
+detach_checkpoint_command (char *args, int from_tty)
{
ptid_t ptid;
if (!args || !*args)
- error (_("Requires argument (fork id to detach)"));
+ error (_("Requires argument (checkpoint id to detach)"));
ptid = fork_id_to_ptid (parse_and_eval_long (args));
if (ptid_equal (ptid, minus_one_ptid))
- error (_("No such fork id, %s"), args);
+ error (_("No such checkpoint id, %s"), args);
if (ptid_equal (ptid, inferior_ptid))
- error (_("Please switch to another fork before detaching the current one"));
+ error (_("\
+Please switch to another checkpoint before detaching the current one"));
if (ptrace (PTRACE_DETACH, PIDGET (ptid), 0, 0))
error (_("Unable to detach %s"), target_pid_to_str (ptid));
delete_fork (ptid);
}
-/* Print information about currently known forks. */
+/* Print information about currently known checkpoints. */
static void
-info_forks_command (char *arg, int from_tty)
+info_checkpoints_command (char *arg, int from_tty)
{
- struct frame_info *cur_frame;
+ struct gdbarch *gdbarch = get_current_arch ();
struct symtab_and_line sal;
- struct symtab *cur_symtab;
struct fork_info *fp;
- int cur_line;
ULONGEST pc;
+ int requested = -1;
+ struct fork_info *printed = NULL;
+
+ if (arg && *arg)
+ requested = (int) parse_and_eval_long (arg);
for (fp = fork_list; fp; fp = fp->next)
{
+ if (requested > 0 && fp->num != requested)
+ continue;
+
+ printed = fp;
if (ptid_equal (fp->ptid, inferior_ptid))
{
printf_filtered ("* ");
- pc = read_pc ();
+ pc = regcache_read_pc (get_current_regcache ());
}
else
{
printf_filtered (" ");
- pc = fp->pc;
+ pc = regcache_read_pc (fp->savedregs);
}
printf_filtered ("%d %s", fp->num, target_pid_to_str (fp->ptid));
if (fp->num == 0)
printf_filtered (_(" (main process)"));
printf_filtered (_(" at "));
- deprecated_print_address_numeric (pc, 1, gdb_stdout);
+ fputs_filtered (paddress (gdbarch, pc), gdb_stdout);
sal = find_pc_line (pc, 0);
if (sal.symtab)
putchar_filtered ('\n');
}
+ if (printed == NULL)
+ {
+ if (requested > 0)
+ printf_filtered (_("No checkpoint number %d.\n"), requested);
+ else
+ printf_filtered (_("No checkpoints.\n"));
+ }
}
-/* Save/restore mode variable 'detach_fork':
- We need to temporarily take over this mode variable, while
- preserving the user-specified state, and make sure that it
- gets restored in case of error.
-
- The int pointer that we use comes from the caller, so we can
- be called more than once (even though currently we don't need to). */
+/* The PID of the process we're checkpointing. */
+static int checkpointing_pid = 0;
-static void
-restore_detach_fork (void *arg)
+int
+linux_fork_checkpointing_p (int pid)
{
- detach_fork = *(int *) arg;
-}
-
-static struct cleanup *
-save_detach_fork (int *saved_val)
-{
- *saved_val = detach_fork;
- return make_cleanup (restore_detach_fork, (void *) saved_val);
+ return (checkpointing_pid == pid);
}
static void
checkpoint_command (char *args, int from_tty)
{
+ struct objfile *fork_objf;
+ struct gdbarch *gdbarch;
struct target_waitstatus last_target_waitstatus;
ptid_t last_target_ptid;
struct value *fork_fn = NULL, *ret;
struct fork_info *fp;
pid_t retpid;
struct cleanup *old_chain;
- long i;
- /* Make this temp var static, 'cause it's used in the error context. */
- static int temp_detach_fork;
/* Make the inferior fork, record its (and gdb's) state. */
if (lookup_minimal_symbol ("fork", NULL, NULL) != NULL)
- fork_fn = find_function_in_inferior ("fork");
+ fork_fn = find_function_in_inferior ("fork", &fork_objf);
if (!fork_fn)
if (lookup_minimal_symbol ("_fork", NULL, NULL) != NULL)
- fork_fn = find_function_in_inferior ("fork");
+ fork_fn = find_function_in_inferior ("fork", &fork_objf);
if (!fork_fn)
error (_("checkpoint: can't find fork function in inferior."));
- ret = value_from_longest (builtin_type_int, 0);
- old_chain = save_detach_fork (&temp_detach_fork);
- detach_fork = 0;
+ gdbarch = get_objfile_arch (fork_objf);
+ ret = value_from_longest (builtin_type (gdbarch)->builtin_int, 0);
+
+ /* Tell linux-nat.c that we're checkpointing this inferior. */
+ old_chain = make_cleanup_restore_integer (&checkpointing_pid);
+ checkpointing_pid = PIDGET (inferior_ptid);
+
ret = call_function_by_hand (fork_fn, 0, &ret);
do_cleanups (old_chain);
if (!ret) /* Probably can't happen. */
{
int parent_pid;
- printf_filtered (_("checkpoint: fork returned pid %ld.\n"),
+ printf_filtered (_("checkpoint: fork returned pid %ld.\n"),
(long) retpid);
if (info_verbose)
{
parent_pid = ptid_get_lwp (last_target_ptid);
if (parent_pid == 0)
parent_pid = ptid_get_pid (last_target_ptid);
- printf_filtered (_(" gdb says parent = %ld.\n"),
+ printf_filtered (_(" gdb says parent = %ld.\n"),
(long) parent_pid);
}
}
if (!fp)
error (_("Failed to find new fork"));
fork_save_infrun_state (fp, 1);
+ fp->parent_ptid = last_target_ptid;
}
static void
linux_fork_context (struct fork_info *newfp, int from_tty)
{
/* Now we attempt to switch processes. */
- struct fork_info *oldfp = find_fork_ptid (inferior_ptid);
- ptid_t ptid;
- int id, i;
+ struct fork_info *oldfp;
- if (!newfp)
- error (_("No such fork/process"));
+ gdb_assert (newfp != NULL);
- if (!oldfp)
- oldfp = add_fork (ptid_get_pid (inferior_ptid));
+ oldfp = find_fork_ptid (inferior_ptid);
+ gdb_assert (oldfp != NULL);
fork_save_infrun_state (oldfp, 1);
+ remove_breakpoints ();
fork_load_infrun_state (newfp);
+ insert_breakpoints ();
- printf_filtered (_("Switching to %s\n"),
+ printf_filtered (_("Switching to %s\n"),
target_pid_to_str (inferior_ptid));
print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
}
-/* Switch inferior process (fork) context, by process id. */
-static void
-process_command (char *args, int from_tty)
-{
- struct fork_info *fp;
-
- if (!args || !*args)
- error (_("Requires argument (process id to switch to)"));
-
- if ((fp = find_fork_pid (parse_and_eval_long (args))) == NULL)
- error (_("Not found: process id %s"), args);
-
- linux_fork_context (fp, from_tty);
-}
-
-/* Switch inferior process (fork) context, by fork id. */
-static void
-fork_command (char *args, int from_tty)
-{
- struct fork_info *fp;
-
- if (!args || !*args)
- error (_("Requires argument (fork id to switch to)"));
-
- if ((fp = find_fork_id (parse_and_eval_long (args))) == NULL)
- error (_("Not found: fork id %s"), args);
-
- linux_fork_context (fp, from_tty);
-}
-
-/* Switch inferior process (fork) context, by checkpoint id. */
+/* Switch inferior process (checkpoint) context, by checkpoint id. */
static void
restart_command (char *args, int from_tty)
{
{
init_fork_list ();
- /* Set/show detach-on-fork: user-settable mode. */
-
- add_setshow_boolean_cmd ("detach-on-fork", class_obscure, &detach_fork, _("\
-Set whether gdb will detach the child of a fork."), _("\
-Show whether gdb will detach the child of a fork."), _("\
-Tells gdb whether to detach the child of a fork."),
- NULL, NULL, &setlist, &showlist);
-
- /* Set/show restart-auto-finish: user-settable count. Causes the
- first "restart" of a fork to do some number of "finish" commands
- before returning to user.
-
- Useful because otherwise the virgin fork process will be stopped
- somewhere in the un-interesting fork system call. */
-
/* Checkpoint command: create a fork of the inferior process
and set it aside for later debugging. */
add_com ("checkpoint", class_obscure, checkpoint_command, _("\
Fork a duplicate process (experimental)."));
- /* Restart command: restore the context of a specified fork
- process. May be used for "program forks" as well as for
- "debugger forks" (checkpoints). */
+ /* Restart command: restore the context of a specified checkpoint
+ process. */
add_com ("restart", class_obscure, restart_command, _("\
restart <n>: restore program context from a checkpoint.\n\
Argument 'n' is checkpoint ID, as displayed by 'info checkpoints'."));
- /* Delete-checkpoint command: kill the process and remove it from
- fork list. */
+ /* Delete checkpoint command: kill the process and remove it from
+ the fork list. */
- add_com ("delete-checkpoint", class_obscure, delete_fork_command, _("\
-Delete a fork/checkpoint (experimental)."));
+ add_cmd ("checkpoint", class_obscure, delete_checkpoint_command, _("\
+Delete a checkpoint (experimental)."),
+ &deletelist);
- /* Detach-checkpoint command: release the process to run independantly,
+ /* Detach checkpoint command: release the process to run independently,
and remove it from the fork list. */
- add_com ("detach-checkpoint", class_obscure, detach_fork_command, _("\
-Detach from a fork/checkpoint (experimental)."));
+ add_cmd ("checkpoint", class_obscure, detach_checkpoint_command, _("\
+Detach from a checkpoint (experimental)."),
+ &detachlist);
- /* Info checkpoints command: list all forks/checkpoints
+ /* Info checkpoints command: list all forks/checkpoints
currently under gdb's control. */
- add_info ("checkpoints", info_forks_command,
- _("IDs of currently known forks/checkpoints."));
-
- /* Command aliases (let "fork" and "checkpoint" be used
- interchangeably). */
-
- add_com_alias ("delete-fork", "delete-checkpoint", class_obscure, 1);
- add_com_alias ("detach-fork", "detach-checkpoint", class_obscure, 1);
- add_info_alias ("forks", "checkpoints", 0);
-
- /* "fork <n>" (by analogy to "thread <n>"). */
- add_com ("fork", class_obscure, fork_command, _("\
-fork <n>: Switch between forked processes.\n\
-Argument 'n' is fork ID, as displayed by 'info forks'."));
-
- /* "process <proc id>" as opposed to "fork <fork id>". */
- add_com ("process", class_obscure, process_command, _("\
-process <pid>: Switch between forked processes.\n\
-Argument 'pid' is process ID, as displayed by 'info forks' or 'shell ps'."));
+ add_info ("checkpoints", info_checkpoints_command,
+ _("IDs of currently known checkpoints."));
}
projects / deliverable / binutils-gdb.git / blobdiff