/* GNU/Linux native-dependent code for debugging multiple forks.
- Copyright (C) 2005-2014 Free Software Foundation, Inc.
+ Copyright (C) 2005-2020 Free Software Foundation, Inc.
This file is part of GDB.
#include "defs.h"
#include "arch-utils.h"
#include "inferior.h"
+#include "infrun.h"
#include "regcache.h"
#include "gdbcmd.h"
#include "infcall.h"
#include "objfiles.h"
-#include "gdb_assert.h"
-#include <string.h>
#include "linux-fork.h"
#include "linux-nat.h"
#include "gdbthread.h"
#include "source.h"
-#include <sys/ptrace.h>
-#include "gdb_wait.h"
+#include "nat/gdb_ptrace.h"
+#include "gdbsupport/gdb_wait.h"
#include <dirent.h>
#include <ctype.h>
-struct fork_info *fork_list;
-static int highest_fork_num;
-
-/* Prevent warning from -Wmissing-prototypes. */
-extern void _initialize_linux_fork (void);
+#include <list>
/* 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
- having to actually switch contexts. */
- int clobber_regs; /* True if we should restore saved regs. */
- off_t *filepos; /* Set of open file descriptors' offsets. */
- int maxfd;
+ explicit fork_info (pid_t pid)
+ : ptid (pid, pid, 0)
+ {
+ }
+
+ ~fork_info ()
+ {
+ /* Notes on step-resume breakpoints: since this is a concern for
+ threads, let's convince ourselves that it's not a concern for
+ forks. There are two ways for a fork_info to be created.
+ First, by the checkpoint command, in which case we're at a gdb
+ prompt and there can't be any step-resume breakpoint. Second,
+ by a fork in the user program, in which case we *may* have
+ stepped into the fork call, but regardless of whether we follow
+ the parent or the child, we will return to the same place and
+ the step-resume breakpoint, if any, will take care of itself as
+ usual. And unlike threads, we do not save a private copy of
+ the step-resume breakpoint -- so we're OK. */
+
+ if (savedregs)
+ delete savedregs;
+ if (filepos)
+ xfree (filepos);
+ }
+
+ ptid_t ptid = null_ptid;
+ ptid_t parent_ptid = null_ptid;
+
+ /* Convenient handle (GDB fork id). */
+ int num = 0;
+
+ /* Convenient for info fork, saves having to actually switch
+ contexts. */
+ readonly_detached_regcache *savedregs = nullptr;
+
+ CORE_ADDR pc = 0;
+
+ /* Set of open file descriptors' offsets. */
+ off_t *filepos = nullptr;
+
+ int maxfd = 0;
};
+static std::list<fork_info> fork_list;
+static int highest_fork_num;
+
/* Fork list methods: */
int
forks_exist_p (void)
{
- return (fork_list != NULL);
+ return !fork_list.empty ();
}
-/* Add a fork to the internal fork list. */
+/* Return the last fork in the list. */
-struct fork_info *
-add_fork (pid_t pid)
+static struct fork_info *
+find_last_fork (void)
{
- struct fork_info *fp;
-
- if (fork_list == NULL && pid != ptid_get_pid (inferior_ptid))
- {
- /* Special case -- if this is the first fork in the list
- (the list is hitherto empty), and if this new fork is
- NOT the current inferior_ptid, then add inferior_ptid
- first, as a special zeroeth fork id. */
- highest_fork_num = -1;
- add_fork (ptid_get_pid (inferior_ptid)); /* safe recursion */
- }
+ if (fork_list.empty ())
+ return NULL;
- fp = XCNEW (struct fork_info);
- fp->ptid = ptid_build (pid, pid, 0);
- fp->num = ++highest_fork_num;
- fp->next = fork_list;
- fork_list = fp;
- return fp;
+ return &fork_list.back ();
}
-static void
-free_fork (struct fork_info *fp)
-{
- /* Notes on step-resume breakpoints: since this is a concern for
- threads, let's convince ourselves that it's not a concern for
- forks. There are two ways for a fork_info to be created. First,
- by the checkpoint command, in which case we're at a gdb prompt
- and there can't be any step-resume breakpoint. Second, by a fork
- in the user program, in which case we *may* have stepped into the
- fork call, but regardless of whether we follow the parent or the
- child, we will return to the same place and the step-resume
- breakpoint, if any, will take care of itself as usual. And
- unlike threads, we do not save a private copy of the step-resume
- breakpoint -- so we're OK. */
-
- if (fp)
- {
- if (fp->savedregs)
- regcache_xfree (fp->savedregs);
- if (fp->filepos)
- xfree (fp->filepos);
- xfree (fp);
- }
-}
+/* Return true iff there's one fork in the list. */
-static void
-delete_fork (ptid_t ptid)
+static bool
+one_fork_p ()
{
- struct fork_info *fp, *fpprev;
-
- fpprev = NULL;
-
- linux_nat_forget_process (ptid_get_pid (ptid));
+ return (!fork_list.empty ()
+ && &fork_list.front () == &fork_list.back ());
+}
- for (fp = fork_list; fp; fpprev = fp, fp = fp->next)
- if (ptid_equal (fp->ptid, ptid))
- break;
+/* Add a new fork to the internal fork list. */
- if (!fp)
- return;
+void
+add_fork (pid_t pid)
+{
+ fork_list.emplace_back (pid);
- if (fpprev)
- fpprev->next = fp->next;
- else
- fork_list = fp->next;
+ if (one_fork_p ())
+ highest_fork_num = 0;
- free_fork (fp);
+ fork_info *fp = &fork_list.back ();
+ fp->num = ++highest_fork_num;
+}
- /* 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. */
- if (fork_list != NULL && fork_list->next == NULL &&
- ptid_equal (fork_list->ptid, inferior_ptid))
- {
- /* Last fork -- delete from list and handle as solo process
- (should be a safe recursion). */
- delete_fork (inferior_ptid);
- }
+static void
+delete_fork (ptid_t ptid)
+{
+ linux_target->low_forget_process (ptid.pid ());
+
+ for (auto it = fork_list.begin (); it != fork_list.end (); ++it)
+ if (it->ptid == ptid)
+ {
+ fork_list.erase (it);
+
+ /* 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. */
+ if (one_fork_p () && fork_list.front ().ptid == inferior_ptid)
+ {
+ /* Last fork -- delete from list and handle as solo
+ process (should be a safe recursion). */
+ delete_fork (inferior_ptid);
+ }
+ return;
+ }
}
/* Find a fork_info by matching PTID. */
static struct fork_info *
find_fork_ptid (ptid_t ptid)
{
- struct fork_info *fp;
-
- for (fp = fork_list; fp; fp = fp->next)
- if (ptid_equal (fp->ptid, ptid))
- return fp;
+ for (fork_info &fi : fork_list)
+ if (fi.ptid == ptid)
+ return &fi;
return NULL;
}
static struct fork_info *
find_fork_id (int num)
{
- struct fork_info *fp;
-
- for (fp = fork_list; fp; fp = fp->next)
- if (fp->num == num)
- return fp;
+ for (fork_info &fi : fork_list)
+ if (fi.num == num)
+ return &fi;
return NULL;
}
extern struct fork_info *
find_fork_pid (pid_t pid)
{
- struct fork_info *fp;
-
- for (fp = fork_list; fp; fp = fp->next)
- if (pid == ptid_get_pid (fp->ptid))
- return fp;
+ for (fork_info &fi : fork_list)
+ if (pid == fi.ptid.pid ())
+ return &fi;
return NULL;
}
if (fork)
return fork->ptid;
else
- return pid_to_ptid (-1);
-}
-
-static void
-init_fork_list (void)
-{
- struct fork_info *fp, *fpnext;
-
- if (!fork_list)
- return;
-
- for (fp = fork_list; fp; fp = fpnext)
- {
- fpnext = fp->next;
- free_fork (fp);
- }
-
- fork_list = NULL;
+ return ptid_t (-1);
}
/* Fork list <-> gdb interface. */
{
char exp[80];
- snprintf (&exp[0], sizeof (exp), "lseek (%d, %ld, %d)",
+ snprintf (&exp[0], sizeof (exp), "(long) lseek (%d, %ld, %d)",
fd, (long) offset, whence);
return (off_t) parse_and_eval_long (&exp[0]);
}
static void
fork_load_infrun_state (struct fork_info *fp)
{
- extern void nullify_last_target_wait_ptid ();
int i;
linux_nat_switch_fork (fp->ptid);
- if (fp->savedregs && fp->clobber_regs)
- regcache_cpy (get_current_regcache (), fp->savedregs);
+ if (fp->savedregs)
+ get_current_regcache ()->restore (fp->savedregs);
registers_changed ();
reinit_frame_cache ();
- stop_pc = regcache_read_pc (get_current_regcache ());
+ inferior_thread ()->suspend.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. */
+/* Save infrun state for the fork FP. */
static void
-fork_save_infrun_state (struct fork_info *fp, int clobber_regs)
+fork_save_infrun_state (struct fork_info *fp)
{
char path[PATH_MAX];
struct dirent *de;
DIR *d;
if (fp->savedregs)
- regcache_xfree (fp->savedregs);
+ delete fp->savedregs;
- fp->savedregs = regcache_dup (get_current_regcache ());
- fp->clobber_regs = clobber_regs;
+ fp->savedregs = new readonly_detached_regcache (*get_current_regcache ());
+ fp->pc = regcache_read_pc (get_current_regcache ());
- if (clobber_regs)
+ /* Now save the 'state' (file position) of all open file descriptors.
+ Unfortunately fork does not take care of that for us... */
+ snprintf (path, PATH_MAX, "/proc/%ld/fd", (long) fp->ptid.pid ());
+ if ((d = opendir (path)) != NULL)
{
- /* Now save the 'state' (file position) of all open file descriptors.
- Unfortunately fork does not take care of that for us... */
- snprintf (path, PATH_MAX, "/proc/%ld/fd",
- (long) ptid_get_pid (fp->ptid));
- if ((d = opendir (path)) != NULL)
+ long tmp;
+
+ fp->maxfd = 0;
+ while ((de = readdir (d)) != NULL)
{
- long tmp;
-
- fp->maxfd = 0;
- while ((de = readdir (d)) != NULL)
- {
- /* Count open file descriptors (actually find highest
- numbered). */
- tmp = strtol (&de->d_name[0], NULL, 10);
- if (fp->maxfd < tmp)
- fp->maxfd = tmp;
- }
- /* Allocate array of file positions. */
- fp->filepos = xrealloc (fp->filepos,
- (fp->maxfd + 1) * sizeof (*fp->filepos));
-
- /* Initialize to -1 (invalid). */
- for (tmp = 0; tmp <= fp->maxfd; tmp++)
- fp->filepos[tmp] = -1;
-
- /* Now find actual file positions. */
- rewinddir (d);
- while ((de = readdir (d)) != NULL)
- if (isdigit (de->d_name[0]))
- {
- tmp = strtol (&de->d_name[0], NULL, 10);
- fp->filepos[tmp] = call_lseek (tmp, 0, SEEK_CUR);
- }
- closedir (d);
+ /* Count open file descriptors (actually find highest
+ numbered). */
+ tmp = strtol (&de->d_name[0], NULL, 10);
+ if (fp->maxfd < tmp)
+ fp->maxfd = tmp;
}
+ /* Allocate array of file positions. */
+ fp->filepos = XRESIZEVEC (off_t, fp->filepos, fp->maxfd + 1);
+
+ /* Initialize to -1 (invalid). */
+ for (tmp = 0; tmp <= fp->maxfd; tmp++)
+ fp->filepos[tmp] = -1;
+
+ /* Now find actual file positions. */
+ rewinddir (d);
+ while ((de = readdir (d)) != NULL)
+ if (isdigit (de->d_name[0]))
+ {
+ tmp = strtol (&de->d_name[0], NULL, 10);
+ fp->filepos[tmp] = call_lseek (tmp, 0, SEEK_CUR);
+ }
+ closedir (d);
}
}
status for it) -- however any process may be a child
or a parent, so may get a SIGCHLD from a previously
killed child. Wait them all out. */
- struct fork_info *fp;
- pid_t pid, ret;
- int status;
- for (fp = fork_list; fp; fp = fp->next)
+ for (fork_info &fi : fork_list)
{
- pid = ptid_get_pid (fp->ptid);
+ pid_t pid = fi.ptid.pid ();
+ int status;
+ pid_t ret;
do {
/* Use SIGKILL instead of PTRACE_KILL because the former works even
if the thread is running, while the later doesn't. */
died. MVS comment cut-and-pasted from linux-nat. */
} while (ret == pid && WIFSTOPPED (status));
}
- init_fork_list (); /* Clear list, prepare to start fresh. */
+
+ /* Clear list, prepare to start fresh. */
+ fork_list.clear ();
}
/* The current inferior_ptid has exited, but there are other viable
void
linux_fork_mourn_inferior (void)
{
+ struct fork_info *last;
+ int status;
+
/* Wait just one more time to collect the inferior's exit status.
Do not check whether this succeeds though, since we may be
dealing with a process that we attached to. Such a process will
only report its exit status to its original parent. */
- int status;
-
- waitpid (ptid_get_pid (inferior_ptid), &status, 0);
+ waitpid (inferior_ptid.pid (), &status, 0);
/* OK, presumably inferior_ptid is the one who has exited.
We need to delete that one from the fork_list, and switch
/* 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);
+ gdb_assert (!fork_list.empty ());
- fork_load_infrun_state (fork_list);
+ last = find_last_fork ();
+ fork_load_infrun_state (last);
printf_filtered (_("[Switching to %s]\n"),
- target_pid_to_str (inferior_ptid));
+ target_pid_to_str (inferior_ptid).c_str ());
/* If there's only one fork, switch back to non-fork mode. */
- if (fork_list->next == NULL)
+ if (one_fork_p ())
delete_fork (inferior_ptid);
}
the first available. */
void
-linux_fork_detach (const char *args, int from_tty)
+linux_fork_detach (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, ptid_get_pid (inferior_ptid), 0, 0))
- error (_("Unable to detach %s"), target_pid_to_str (inferior_ptid));
+ if (ptrace (PTRACE_DETACH, inferior_ptid.pid (), 0, 0))
+ error (_("Unable to detach %s"),
+ target_pid_to_str (inferior_ptid).c_str ());
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);
+ gdb_assert (!fork_list.empty ());
- fork_load_infrun_state (fork_list);
+ fork_load_infrun_state (&fork_list.front ());
if (from_tty)
printf_filtered (_("[Switching to %s]\n"),
- target_pid_to_str (inferior_ptid));
+ target_pid_to_str (inferior_ptid).c_str ());
/* If there's only one fork, switch back to non-fork mode. */
- if (fork_list->next == NULL)
+ if (one_fork_p ())
delete_fork (inferior_ptid);
}
-static void
-inferior_call_waitpid_cleanup (void *fp)
-{
- struct fork_info *oldfp = fp;
+/* Temporarily switch to the infrun state stored on the fork_info
+ identified by a given ptid_t. When this object goes out of scope,
+ restore the currently selected infrun state. */
- if (oldfp)
- {
- /* Switch back to inferior_ptid. */
- remove_breakpoints ();
- fork_load_infrun_state (oldfp);
- insert_breakpoints ();
- }
-}
+class scoped_switch_fork_info
+{
+public:
+ /* Switch to the infrun state held on the fork_info identified by
+ PPTID. If PPTID is the current inferior then no switch is done. */
+ explicit scoped_switch_fork_info (ptid_t pptid)
+ : m_oldfp (nullptr)
+ {
+ if (pptid != inferior_ptid)
+ {
+ struct fork_info *newfp = nullptr;
+
+ /* Switch to pptid. */
+ m_oldfp = find_fork_ptid (inferior_ptid);
+ gdb_assert (m_oldfp != nullptr);
+ newfp = find_fork_ptid (pptid);
+ gdb_assert (newfp != nullptr);
+ fork_save_infrun_state (m_oldfp);
+ remove_breakpoints ();
+ fork_load_infrun_state (newfp);
+ insert_breakpoints ();
+ }
+ }
+
+ /* Restore the previously selected infrun state. If the constructor
+ didn't need to switch states, then nothing is done here either. */
+ ~scoped_switch_fork_info ()
+ {
+ if (m_oldfp != nullptr)
+ {
+ /* Switch back to inferior_ptid. */
+ try
+ {
+ remove_breakpoints ();
+ fork_load_infrun_state (m_oldfp);
+ insert_breakpoints ();
+ }
+ catch (const gdb_exception &ex)
+ {
+ warning (_("Couldn't restore checkpoint state in %s: %s"),
+ target_pid_to_str (m_oldfp->ptid).c_str (),
+ ex.what ());
+ }
+ }
+ }
+
+ DISABLE_COPY_AND_ASSIGN (scoped_switch_fork_info);
+
+private:
+ /* The fork_info for the previously selected infrun state, or nullptr if
+ we were already in the desired state, and nothing needs to be
+ restored. */
+ struct fork_info *m_oldfp;
+};
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 (newfp != 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);
+ scoped_switch_fork_info switch_fork_info (pptid);
/* Get the waitpid_fn. */
- if (lookup_minimal_symbol ("waitpid", NULL, NULL) != NULL)
+ if (lookup_minimal_symbol ("waitpid", NULL, NULL).minsym != NULL)
waitpid_fn = find_function_in_inferior ("waitpid", &waitpid_objf);
- if (!waitpid_fn && lookup_minimal_symbol ("_waitpid", NULL, NULL) != NULL)
+ if (!waitpid_fn
+ && lookup_minimal_symbol ("_waitpid", NULL, NULL).minsym != NULL)
waitpid_fn = find_function_in_inferior ("_waitpid", &waitpid_objf);
- if (!waitpid_fn)
- goto out;
+ if (waitpid_fn != nullptr)
+ {
+ struct gdbarch *gdbarch = get_current_arch ();
+ struct value *argv[3], *retv;
- /* 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;
+ /* 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);
- retv = call_function_by_hand (waitpid_fn, 3, argv);
- if (value_as_long (retv) < 0)
- goto out;
+ retv = call_function_by_hand (waitpid_fn, NULL, argv);
- ret = 0;
+ if (value_as_long (retv) >= 0)
+ ret = 0;
+ }
-out:
- do_cleanups (old_cleanup);
return ret;
}
/* Fork list <-> user interface. */
static void
-delete_checkpoint_command (char *args, int from_tty)
+delete_checkpoint_command (const char *args, int from_tty)
{
ptid_t ptid, pptid;
struct fork_info *fi;
error (_("Requires argument (checkpoint id to delete)"));
ptid = fork_id_to_ptid (parse_and_eval_long (args));
- if (ptid_equal (ptid, minus_one_ptid))
+ if (ptid == minus_one_ptid)
error (_("No such checkpoint id, %s"), args);
- if (ptid_equal (ptid, inferior_ptid))
+ if (ptid == inferior_ptid)
error (_("\
Please switch to another checkpoint before deleting the current one"));
- if (ptrace (PTRACE_KILL, ptid_get_pid (ptid), 0, 0))
- error (_("Unable to kill pid %s"), target_pid_to_str (ptid));
+ if (ptrace (PTRACE_KILL, ptid.pid (), 0, 0))
+ error (_("Unable to kill pid %s"), target_pid_to_str (ptid).c_str ());
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));
+ printf_filtered (_("Killed %s\n"), target_pid_to_str (ptid).c_str ());
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
+ If fi->parent_ptid is a part of lwp and it is stopped, waitpid the
ptid. */
- if ((!find_thread_ptid (pptid) && find_fork_ptid (pptid))
- || (find_thread_ptid (pptid) && is_stopped (pptid)))
+ thread_info *parent = find_thread_ptid (linux_target, pptid);
+ if ((parent == NULL && find_fork_ptid (pptid))
+ || (parent != NULL && parent->state == THREAD_STOPPED))
{
- if (inferior_call_waitpid (pptid, ptid_get_pid (ptid)))
- warning (_("Unable to wait pid %s"), target_pid_to_str (ptid));
+ if (inferior_call_waitpid (pptid, ptid.pid ()))
+ warning (_("Unable to wait pid %s"),
+ target_pid_to_str (ptid).c_str ());
}
}
static void
-detach_checkpoint_command (char *args, int from_tty)
+detach_checkpoint_command (const char *args, int from_tty)
{
ptid_t ptid;
error (_("Requires argument (checkpoint id to detach)"));
ptid = fork_id_to_ptid (parse_and_eval_long (args));
- if (ptid_equal (ptid, minus_one_ptid))
+ if (ptid == minus_one_ptid)
error (_("No such checkpoint id, %s"), args);
- if (ptid_equal (ptid, inferior_ptid))
+ if (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 (ptrace (PTRACE_DETACH, ptid.pid (), 0, 0))
+ error (_("Unable to detach %s"), target_pid_to_str (ptid).c_str ());
if (from_tty)
- printf_filtered (_("Detached %s\n"), target_pid_to_str (ptid));
+ printf_filtered (_("Detached %s\n"), target_pid_to_str (ptid).c_str ());
delete_fork (ptid);
}
/* Print information about currently known checkpoints. */
static void
-info_checkpoints_command (char *arg, int from_tty)
+info_checkpoints_command (const 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;
+ const fork_info *printed = NULL;
if (arg && *arg)
requested = (int) parse_and_eval_long (arg);
- for (fp = fork_list; fp; fp = fp->next)
+ for (const fork_info &fi : fork_list)
{
- if (requested > 0 && fp->num != requested)
+ if (requested > 0 && fi.num != requested)
continue;
- printed = fp;
- if (ptid_equal (fp->ptid, inferior_ptid))
- {
- printf_filtered ("* ");
- pc = regcache_read_pc (get_current_regcache ());
- }
+ printed = &fi;
+ if (fi.ptid == inferior_ptid)
+ printf_filtered ("* ");
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 (" ");
+
+ ULONGEST pc = fi.pc;
+ printf_filtered ("%d %s", fi.num, target_pid_to_str (fi.ptid).c_str ());
+ if (fi.num == 0)
printf_filtered (_(" (main process)"));
printf_filtered (_(" at "));
fputs_filtered (paddress (gdbarch, pc), gdb_stdout);
- sal = find_pc_line (pc, 0);
+ symtab_and_line sal = find_pc_line (pc, 0);
if (sal.symtab)
printf_filtered (_(", file %s"),
symtab_to_filename_for_display (sal.symtab));
msym = lookup_minimal_symbol_by_pc (pc);
if (msym.minsym)
- printf_filtered (", <%s>", SYMBOL_LINKAGE_NAME (msym.minsym));
+ printf_filtered (", <%s>", msym.minsym->linkage_name ());
}
putchar_filtered ('\n');
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)
+static bool
+inf_has_multiple_threads ()
{
int count = 0;
- iterate_over_threads (inf_has_multiple_thread_cb, &count);
- return (count > 1);
+ /* Return true as soon as we see the second thread of the current
+ inferior. */
+ for (thread_info *tp ATTRIBUTE_UNUSED : current_inferior ()->threads ())
+ if (++count > 1)
+ return true;
+
+ return false;
}
static void
-checkpoint_command (char *args, int from_tty)
+checkpoint_command (const char *args, int from_tty)
{
struct objfile *fork_objf;
struct gdbarch *gdbarch;
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."));
/* Make the inferior fork, record its (and gdb's) state. */
- if (lookup_minimal_symbol ("fork", NULL, NULL) != NULL)
+ 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) != NULL)
+ 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."));
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);
+ {
+ scoped_restore save_pid
+ = make_scoped_restore (&checkpointing_pid, inferior_ptid.pid ());
+
+ ret = call_function_by_hand (fork_fn, NULL, {});
+ }
- 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);
+ get_last_target_status (nullptr, &last_target_ptid, &last_target_waitstatus);
+
+ fp = find_fork_pid (retpid);
+
if (from_tty)
{
int parent_pid;
- printf_filtered (_("checkpoint: fork returned pid %ld.\n"),
- (long) retpid);
+ 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);
+ parent_pid = last_target_ptid.lwp ();
if (parent_pid == 0)
- parent_pid = ptid_get_pid (last_target_ptid);
+ parent_pid = last_target_ptid.pid ();
printf_filtered (_(" gdb says parent = %ld.\n"),
(long) parent_pid);
}
}
- fp = find_fork_pid (retpid);
if (!fp)
error (_("Failed to find new fork"));
- fork_save_infrun_state (fp, 1);
+
+ if (one_fork_p ())
+ {
+ /* Special case -- if this is the first fork in the list (the
+ list was hitherto empty), then add inferior_ptid first, as a
+ special zeroeth fork id. */
+ fork_list.emplace_front (inferior_ptid.pid ());
+ }
+
+ fork_save_infrun_state (fp);
fp->parent_ptid = last_target_ptid;
}
oldfp = find_fork_ptid (inferior_ptid);
gdb_assert (oldfp != NULL);
- fork_save_infrun_state (oldfp, 1);
+ fork_save_infrun_state (oldfp);
remove_breakpoints ();
fork_load_infrun_state (newfp);
insert_breakpoints ();
printf_filtered (_("Switching to %s\n"),
- target_pid_to_str (inferior_ptid));
+ target_pid_to_str (inferior_ptid).c_str ());
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)
+restart_command (const char *args, int from_tty)
{
struct fork_info *fp;
void
_initialize_linux_fork (void)
{
- init_fork_list ();
-
/* Checkpoint command: create a fork of the inferior process
and set it aside for later debugging. */
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'."));
+Restore program context from a checkpoint.\n\
+Usage: restart N\n\
+Argument N is checkpoint ID, as displayed by 'info checkpoints'."));
/* Delete checkpoint command: kill the process and remove it from
the fork list. */