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gdb/ChangeLog: Update year range in copyright notice of all files.
817 lines
22 KiB
C
817 lines
22 KiB
C
/* GNU/Linux native-dependent code for debugging multiple forks.
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Copyright (C) 2005-2016 Free Software Foundation, Inc.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "arch-utils.h"
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#include "inferior.h"
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#include "infrun.h"
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#include "regcache.h"
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#include "gdbcmd.h"
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#include "infcall.h"
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#include "objfiles.h"
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#include "linux-fork.h"
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#include "linux-nat.h"
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#include "gdbthread.h"
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#include "source.h"
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#include "nat/gdb_ptrace.h"
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#include "gdb_wait.h"
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#include <dirent.h>
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#include <ctype.h>
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struct fork_info *fork_list;
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static int highest_fork_num;
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/* Prevent warning from -Wmissing-prototypes. */
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extern void _initialize_linux_fork (void);
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/* Fork list data structure: */
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struct fork_info
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{
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struct fork_info *next;
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ptid_t ptid;
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ptid_t parent_ptid;
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int num; /* Convenient handle (GDB fork id). */
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struct regcache *savedregs; /* Convenient for info fork, saves
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having to actually switch contexts. */
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int clobber_regs; /* True if we should restore saved regs. */
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off_t *filepos; /* Set of open file descriptors' offsets. */
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int maxfd;
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};
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/* Fork list methods: */
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int
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forks_exist_p (void)
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{
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return (fork_list != NULL);
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}
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/* Return the last fork in the list. */
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static struct fork_info *
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find_last_fork (void)
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{
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struct fork_info *last;
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if (fork_list == NULL)
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return NULL;
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for (last = fork_list; last->next != NULL; last = last->next)
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;
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return last;
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}
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/* Add a fork to the internal fork list. */
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struct fork_info *
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add_fork (pid_t pid)
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{
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struct fork_info *fp;
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if (fork_list == NULL && pid != ptid_get_pid (inferior_ptid))
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{
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/* Special case -- if this is the first fork in the list
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(the list is hitherto empty), and if this new fork is
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NOT the current inferior_ptid, then add inferior_ptid
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first, as a special zeroeth fork id. */
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highest_fork_num = -1;
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add_fork (ptid_get_pid (inferior_ptid)); /* safe recursion */
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}
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fp = XCNEW (struct fork_info);
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fp->ptid = ptid_build (pid, pid, 0);
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fp->num = ++highest_fork_num;
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if (fork_list == NULL)
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fork_list = fp;
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else
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{
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struct fork_info *last = find_last_fork ();
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last->next = fp;
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}
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return fp;
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}
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static void
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free_fork (struct fork_info *fp)
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{
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/* Notes on step-resume breakpoints: since this is a concern for
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threads, let's convince ourselves that it's not a concern for
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forks. There are two ways for a fork_info to be created. First,
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by the checkpoint command, in which case we're at a gdb prompt
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and there can't be any step-resume breakpoint. Second, by a fork
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in the user program, in which case we *may* have stepped into the
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fork call, but regardless of whether we follow the parent or the
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child, we will return to the same place and the step-resume
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breakpoint, if any, will take care of itself as usual. And
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unlike threads, we do not save a private copy of the step-resume
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breakpoint -- so we're OK. */
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if (fp)
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{
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if (fp->savedregs)
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regcache_xfree (fp->savedregs);
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if (fp->filepos)
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xfree (fp->filepos);
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xfree (fp);
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}
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}
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static void
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delete_fork (ptid_t ptid)
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{
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struct fork_info *fp, *fpprev;
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fpprev = NULL;
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linux_nat_forget_process (ptid_get_pid (ptid));
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for (fp = fork_list; fp; fpprev = fp, fp = fp->next)
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if (ptid_equal (fp->ptid, ptid))
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break;
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if (!fp)
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return;
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if (fpprev)
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fpprev->next = fp->next;
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else
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fork_list = fp->next;
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free_fork (fp);
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/* Special case: if there is now only one process in the list,
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and if it is (hopefully!) the current inferior_ptid, then
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remove it, leaving the list empty -- we're now down to the
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default case of debugging a single process. */
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if (fork_list != NULL && fork_list->next == NULL &&
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ptid_equal (fork_list->ptid, inferior_ptid))
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{
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/* Last fork -- delete from list and handle as solo process
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(should be a safe recursion). */
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delete_fork (inferior_ptid);
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}
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}
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/* Find a fork_info by matching PTID. */
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static struct fork_info *
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find_fork_ptid (ptid_t ptid)
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{
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struct fork_info *fp;
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for (fp = fork_list; fp; fp = fp->next)
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if (ptid_equal (fp->ptid, ptid))
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return fp;
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return NULL;
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}
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/* Find a fork_info by matching ID. */
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static struct fork_info *
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find_fork_id (int num)
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{
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struct fork_info *fp;
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for (fp = fork_list; fp; fp = fp->next)
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if (fp->num == num)
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return fp;
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return NULL;
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}
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/* Find a fork_info by matching pid. */
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extern struct fork_info *
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find_fork_pid (pid_t pid)
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{
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struct fork_info *fp;
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for (fp = fork_list; fp; fp = fp->next)
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if (pid == ptid_get_pid (fp->ptid))
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return fp;
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return NULL;
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}
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static ptid_t
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fork_id_to_ptid (int num)
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{
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struct fork_info *fork = find_fork_id (num);
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if (fork)
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return fork->ptid;
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else
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return pid_to_ptid (-1);
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}
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static void
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init_fork_list (void)
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{
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struct fork_info *fp, *fpnext;
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if (!fork_list)
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return;
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for (fp = fork_list; fp; fp = fpnext)
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{
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fpnext = fp->next;
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free_fork (fp);
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}
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fork_list = NULL;
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}
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/* Fork list <-> gdb interface. */
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/* Utility function for fork_load/fork_save.
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Calls lseek in the (current) inferior process. */
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static off_t
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call_lseek (int fd, off_t offset, int whence)
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{
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char exp[80];
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snprintf (&exp[0], sizeof (exp), "lseek (%d, %ld, %d)",
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fd, (long) offset, whence);
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return (off_t) parse_and_eval_long (&exp[0]);
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}
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/* Load infrun state for the fork PTID. */
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static void
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fork_load_infrun_state (struct fork_info *fp)
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{
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extern void nullify_last_target_wait_ptid ();
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int i;
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linux_nat_switch_fork (fp->ptid);
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if (fp->savedregs && fp->clobber_regs)
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regcache_cpy (get_current_regcache (), fp->savedregs);
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registers_changed ();
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reinit_frame_cache ();
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stop_pc = regcache_read_pc (get_current_regcache ());
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nullify_last_target_wait_ptid ();
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/* Now restore the file positions of open file descriptors. */
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if (fp->filepos)
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{
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for (i = 0; i <= fp->maxfd; i++)
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if (fp->filepos[i] != (off_t) -1)
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call_lseek (i, fp->filepos[i], SEEK_SET);
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/* NOTE: I can get away with using SEEK_SET and SEEK_CUR because
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this is native-only. If it ever has to be cross, we'll have
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to rethink this. */
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}
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}
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/* Save infrun state for the fork PTID.
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Exported for use by linux child_follow_fork. */
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static void
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fork_save_infrun_state (struct fork_info *fp, int clobber_regs)
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{
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char path[PATH_MAX];
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struct dirent *de;
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DIR *d;
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if (fp->savedregs)
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regcache_xfree (fp->savedregs);
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fp->savedregs = regcache_dup (get_current_regcache ());
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fp->clobber_regs = clobber_regs;
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if (clobber_regs)
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{
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/* Now save the 'state' (file position) of all open file descriptors.
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Unfortunately fork does not take care of that for us... */
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snprintf (path, PATH_MAX, "/proc/%ld/fd",
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(long) ptid_get_pid (fp->ptid));
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if ((d = opendir (path)) != NULL)
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{
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long tmp;
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fp->maxfd = 0;
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while ((de = readdir (d)) != NULL)
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{
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/* Count open file descriptors (actually find highest
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numbered). */
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tmp = strtol (&de->d_name[0], NULL, 10);
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if (fp->maxfd < tmp)
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fp->maxfd = tmp;
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}
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/* Allocate array of file positions. */
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fp->filepos = XRESIZEVEC (off_t, fp->filepos, fp->maxfd + 1);
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/* Initialize to -1 (invalid). */
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for (tmp = 0; tmp <= fp->maxfd; tmp++)
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fp->filepos[tmp] = -1;
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/* Now find actual file positions. */
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rewinddir (d);
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while ((de = readdir (d)) != NULL)
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if (isdigit (de->d_name[0]))
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{
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tmp = strtol (&de->d_name[0], NULL, 10);
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fp->filepos[tmp] = call_lseek (tmp, 0, SEEK_CUR);
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}
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closedir (d);
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}
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}
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}
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/* Kill 'em all, let God sort 'em out... */
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void
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linux_fork_killall (void)
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{
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/* Walk list and kill every pid. No need to treat the
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current inferior_ptid as special (we do not return a
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status for it) -- however any process may be a child
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or a parent, so may get a SIGCHLD from a previously
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killed child. Wait them all out. */
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struct fork_info *fp;
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pid_t pid, ret;
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int status;
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for (fp = fork_list; fp; fp = fp->next)
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{
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pid = ptid_get_pid (fp->ptid);
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do {
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/* Use SIGKILL instead of PTRACE_KILL because the former works even
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if the thread is running, while the later doesn't. */
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kill (pid, SIGKILL);
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ret = waitpid (pid, &status, 0);
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/* We might get a SIGCHLD instead of an exit status. This is
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aggravated by the first kill above - a child has just
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died. MVS comment cut-and-pasted from linux-nat. */
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} while (ret == pid && WIFSTOPPED (status));
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}
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init_fork_list (); /* Clear list, prepare to start fresh. */
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}
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/* The current inferior_ptid has exited, but there are other viable
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forks to debug. Delete the exiting one and context-switch to the
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first available. */
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void
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linux_fork_mourn_inferior (void)
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{
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struct fork_info *last;
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int status;
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/* Wait just one more time to collect the inferior's exit status.
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Do not check whether this succeeds though, since we may be
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dealing with a process that we attached to. Such a process will
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only report its exit status to its original parent. */
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waitpid (ptid_get_pid (inferior_ptid), &status, 0);
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/* OK, presumably inferior_ptid is the one who has exited.
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We need to delete that one from the fork_list, and switch
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to the next available fork. */
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delete_fork (inferior_ptid);
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/* There should still be a fork - if there's only one left,
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delete_fork won't remove it, because we haven't updated
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inferior_ptid yet. */
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gdb_assert (fork_list);
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last = find_last_fork ();
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fork_load_infrun_state (last);
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printf_filtered (_("[Switching to %s]\n"),
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target_pid_to_str (inferior_ptid));
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/* If there's only one fork, switch back to non-fork mode. */
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if (fork_list->next == NULL)
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delete_fork (inferior_ptid);
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}
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/* The current inferior_ptid is being detached, but there are other
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viable forks to debug. Detach and delete it and context-switch to
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the first available. */
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void
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linux_fork_detach (const char *args, int from_tty)
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{
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/* OK, inferior_ptid is the one we are detaching from. We need to
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delete it from the fork_list, and switch to the next available
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fork. */
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if (ptrace (PTRACE_DETACH, ptid_get_pid (inferior_ptid), 0, 0))
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error (_("Unable to detach %s"), target_pid_to_str (inferior_ptid));
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delete_fork (inferior_ptid);
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/* There should still be a fork - if there's only one left,
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delete_fork won't remove it, because we haven't updated
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inferior_ptid yet. */
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gdb_assert (fork_list);
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fork_load_infrun_state (fork_list);
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if (from_tty)
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printf_filtered (_("[Switching to %s]\n"),
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target_pid_to_str (inferior_ptid));
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/* If there's only one fork, switch back to non-fork mode. */
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if (fork_list->next == NULL)
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delete_fork (inferior_ptid);
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}
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static void
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inferior_call_waitpid_cleanup (void *fp)
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{
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struct fork_info *oldfp = (struct fork_info *) fp;
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if (oldfp)
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{
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/* Switch back to inferior_ptid. */
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remove_breakpoints ();
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fork_load_infrun_state (oldfp);
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insert_breakpoints ();
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}
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}
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static int
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inferior_call_waitpid (ptid_t pptid, int pid)
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{
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struct objfile *waitpid_objf;
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struct value *waitpid_fn = NULL;
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struct value *argv[4], *retv;
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struct gdbarch *gdbarch = get_current_arch ();
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struct fork_info *oldfp = NULL, *newfp = NULL;
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struct cleanup *old_cleanup;
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int ret = -1;
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if (!ptid_equal (pptid, inferior_ptid))
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{
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/* Switch to pptid. */
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oldfp = find_fork_ptid (inferior_ptid);
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gdb_assert (oldfp != NULL);
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newfp = find_fork_ptid (pptid);
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gdb_assert (newfp != NULL);
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fork_save_infrun_state (oldfp, 1);
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remove_breakpoints ();
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fork_load_infrun_state (newfp);
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insert_breakpoints ();
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}
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old_cleanup = make_cleanup (inferior_call_waitpid_cleanup, oldfp);
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/* Get the waitpid_fn. */
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if (lookup_minimal_symbol ("waitpid", NULL, NULL).minsym != NULL)
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waitpid_fn = find_function_in_inferior ("waitpid", &waitpid_objf);
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if (!waitpid_fn
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&& lookup_minimal_symbol ("_waitpid", NULL, NULL).minsym != NULL)
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waitpid_fn = find_function_in_inferior ("_waitpid", &waitpid_objf);
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if (!waitpid_fn)
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goto out;
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/* Get the argv. */
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argv[0] = value_from_longest (builtin_type (gdbarch)->builtin_int, pid);
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argv[1] = value_from_pointer (builtin_type (gdbarch)->builtin_data_ptr, 0);
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argv[2] = value_from_longest (builtin_type (gdbarch)->builtin_int, 0);
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argv[3] = 0;
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retv = call_function_by_hand (waitpid_fn, 3, argv);
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if (value_as_long (retv) < 0)
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goto out;
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ret = 0;
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out:
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do_cleanups (old_cleanup);
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return ret;
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}
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/* Fork list <-> user interface. */
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static void
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delete_checkpoint_command (char *args, int from_tty)
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{
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ptid_t ptid, pptid;
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struct fork_info *fi;
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if (!args || !*args)
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error (_("Requires argument (checkpoint id to delete)"));
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ptid = fork_id_to_ptid (parse_and_eval_long (args));
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if (ptid_equal (ptid, minus_one_ptid))
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error (_("No such checkpoint id, %s"), args);
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if (ptid_equal (ptid, inferior_ptid))
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error (_("\
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Please switch to another checkpoint before deleting the current one"));
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if (ptrace (PTRACE_KILL, ptid_get_pid (ptid), 0, 0))
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error (_("Unable to kill pid %s"), target_pid_to_str (ptid));
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fi = find_fork_ptid (ptid);
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gdb_assert (fi);
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pptid = fi->parent_ptid;
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if (from_tty)
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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, ptid_get_pid (ptid)))
|
|
warning (_("Unable to wait pid %s"), target_pid_to_str (ptid));
|
|
}
|
|
}
|
|
|
|
static void
|
|
detach_checkpoint_command (char *args, int from_tty)
|
|
{
|
|
ptid_t ptid;
|
|
|
|
if (!args || !*args)
|
|
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 checkpoint id, %s"), args);
|
|
|
|
if (ptid_equal (ptid, inferior_ptid))
|
|
error (_("\
|
|
Please switch to another checkpoint before detaching the current one"));
|
|
|
|
if (ptrace (PTRACE_DETACH, ptid_get_pid (ptid), 0, 0))
|
|
error (_("Unable to detach %s"), target_pid_to_str (ptid));
|
|
|
|
if (from_tty)
|
|
printf_filtered (_("Detached %s\n"), target_pid_to_str (ptid));
|
|
|
|
delete_fork (ptid);
|
|
}
|
|
|
|
/* Print information about currently known checkpoints. */
|
|
|
|
static void
|
|
info_checkpoints_command (char *arg, int from_tty)
|
|
{
|
|
struct gdbarch *gdbarch = get_current_arch ();
|
|
struct symtab_and_line sal;
|
|
struct fork_info *fp;
|
|
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 = regcache_read_pc (get_current_regcache ());
|
|
}
|
|
else
|
|
{
|
|
printf_filtered (" ");
|
|
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 "));
|
|
fputs_filtered (paddress (gdbarch, pc), gdb_stdout);
|
|
|
|
sal = find_pc_line (pc, 0);
|
|
if (sal.symtab)
|
|
printf_filtered (_(", file %s"),
|
|
symtab_to_filename_for_display (sal.symtab));
|
|
if (sal.line)
|
|
printf_filtered (_(", line %d"), sal.line);
|
|
if (!sal.symtab && !sal.line)
|
|
{
|
|
struct bound_minimal_symbol msym;
|
|
|
|
msym = lookup_minimal_symbol_by_pc (pc);
|
|
if (msym.minsym)
|
|
printf_filtered (", <%s>", MSYMBOL_LINKAGE_NAME (msym.minsym));
|
|
}
|
|
|
|
putchar_filtered ('\n');
|
|
}
|
|
if (printed == NULL)
|
|
{
|
|
if (requested > 0)
|
|
printf_filtered (_("No checkpoint number %d.\n"), requested);
|
|
else
|
|
printf_filtered (_("No checkpoints.\n"));
|
|
}
|
|
}
|
|
|
|
/* The PID of the process we're checkpointing. */
|
|
static int checkpointing_pid = 0;
|
|
|
|
int
|
|
linux_fork_checkpointing_p (int pid)
|
|
{
|
|
return (checkpointing_pid == pid);
|
|
}
|
|
|
|
/* Callback for iterate over threads. Used to check whether
|
|
the current inferior is multi-threaded. Returns true as soon
|
|
as it sees the second thread of the current inferior. */
|
|
|
|
static int
|
|
inf_has_multiple_thread_cb (struct thread_info *tp, void *data)
|
|
{
|
|
int *count_p = (int *) data;
|
|
|
|
if (current_inferior ()->pid == ptid_get_pid (tp->ptid))
|
|
(*count_p)++;
|
|
|
|
/* Stop the iteration if multiple threads have been detected. */
|
|
return *count_p > 1;
|
|
}
|
|
|
|
/* Return true if the current inferior is multi-threaded. */
|
|
|
|
static int
|
|
inf_has_multiple_threads (void)
|
|
{
|
|
int count = 0;
|
|
|
|
iterate_over_threads (inf_has_multiple_thread_cb, &count);
|
|
return (count > 1);
|
|
}
|
|
|
|
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;
|
|
|
|
if (!target_has_execution)
|
|
error (_("The program is not being run."));
|
|
|
|
/* Ensure that the inferior is not multithreaded. */
|
|
update_thread_list ();
|
|
if (inf_has_multiple_threads ())
|
|
error (_("checkpoint: can't checkpoint multiple threads."));
|
|
|
|
/* Make the inferior fork, record its (and gdb's) state. */
|
|
|
|
if (lookup_minimal_symbol ("fork", NULL, NULL).minsym != NULL)
|
|
fork_fn = find_function_in_inferior ("fork", &fork_objf);
|
|
if (!fork_fn)
|
|
if (lookup_minimal_symbol ("_fork", NULL, NULL).minsym != NULL)
|
|
fork_fn = find_function_in_inferior ("fork", &fork_objf);
|
|
if (!fork_fn)
|
|
error (_("checkpoint: can't find fork function in inferior."));
|
|
|
|
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 = ptid_get_pid (inferior_ptid);
|
|
|
|
ret = call_function_by_hand (fork_fn, 0, &ret);
|
|
do_cleanups (old_chain);
|
|
if (!ret) /* Probably can't happen. */
|
|
error (_("checkpoint: call_function_by_hand returned null."));
|
|
|
|
retpid = value_as_long (ret);
|
|
get_last_target_status (&last_target_ptid, &last_target_waitstatus);
|
|
|
|
fp = find_fork_pid (retpid);
|
|
|
|
if (from_tty)
|
|
{
|
|
int parent_pid;
|
|
|
|
printf_filtered (_("checkpoint %d: fork returned pid %ld.\n"),
|
|
fp != NULL ? fp->num : -1, (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"),
|
|
(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;
|
|
|
|
gdb_assert (newfp != NULL);
|
|
|
|
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"),
|
|
target_pid_to_str (inferior_ptid));
|
|
|
|
print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
|
|
}
|
|
|
|
/* Switch inferior process (checkpoint) context, by checkpoint id. */
|
|
static void
|
|
restart_command (char *args, int from_tty)
|
|
{
|
|
struct fork_info *fp;
|
|
|
|
if (!args || !*args)
|
|
error (_("Requires argument (checkpoint id to restart)"));
|
|
|
|
if ((fp = find_fork_id (parse_and_eval_long (args))) == NULL)
|
|
error (_("Not found: checkpoint id %s"), args);
|
|
|
|
linux_fork_context (fp, from_tty);
|
|
}
|
|
|
|
void
|
|
_initialize_linux_fork (void)
|
|
{
|
|
init_fork_list ();
|
|
|
|
/* 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 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
|
|
the fork list. */
|
|
|
|
add_cmd ("checkpoint", class_obscure, delete_checkpoint_command, _("\
|
|
Delete a checkpoint (experimental)."),
|
|
&deletelist);
|
|
|
|
/* Detach checkpoint command: release the process to run independently,
|
|
and remove it from the fork list. */
|
|
|
|
add_cmd ("checkpoint", class_obscure, detach_checkpoint_command, _("\
|
|
Detach from a checkpoint (experimental)."),
|
|
&detachlist);
|
|
|
|
/* Info checkpoints command: list all forks/checkpoints
|
|
currently under gdb's control. */
|
|
|
|
add_info ("checkpoints", info_checkpoints_command,
|
|
_("IDs of currently known checkpoints."));
|
|
}
|