Use gdb::function_view in iterate_over_threads

This C++-ifies iterate_over_threads, changing it to accept a
gdb::function_view and to return bool.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

gdb/aix-thread.c

@@ -867,16 +867,6 @@ sync_threadlists (pid_t pid)
       }
 }
 
-/* Iterate_over_threads() callback for locating a thread, using
-   the TID of its associated kernel thread.  */
-
-static int
-iter_tid (struct thread_info *thread, void *tidp)
-{
-  const pthdb_tid_t tid = *(pthdb_tid_t *)tidp;
-  return thread->ptid.lwp () == tid;
-}
-
 /* Synchronize libpthdebug's state with the inferior and with GDB,
    generate a composite process/thread <pid> for the current thread,
    Return the ptid of the event thread if one can be found, else
@@ -906,7 +896,10 @@ pd_update (pid_t pid)
 
   tid = get_signaled_thread (pid);
   if (tid != 0)
-    thread = iterate_over_threads (iter_tid, &tid);
+    thread = iterate_over_threads ([&] (struct thread_info *thread)
+      {
+	return thread->ptid.lwp () == tid;
+      });
   if (!thread)
     ptid = ptid_t (pid);
   else

gdb/breakpoint.c

@@ -11831,16 +11831,6 @@ bpstat_remove_bp_location (bpstat *bps, struct breakpoint *bpt)
       }
 }
 
-/* Callback for iterate_over_threads.  */
-static int
-bpstat_remove_breakpoint_callback (struct thread_info *th, void *data)
-{
-  struct breakpoint *bpt = (struct breakpoint *) data;
-
-  bpstat_remove_bp_location (th->control.stop_bpstat, bpt);
-  return 0;
-}
-
 /* See breakpoint.h.  */
 
 void
@@ -12685,7 +12675,11 @@ delete_breakpoint (struct breakpoint *bpt)
      event-top.c won't do anything, and temporary breakpoints with
      commands won't work.  */
 
-  iterate_over_threads (bpstat_remove_breakpoint_callback, bpt);
+  iterate_over_threads ([&] (struct thread_info *th)
+    {
+      bpstat_remove_bp_location (th->control.stop_bpstat, bpt);
+      return false;
+    });
 
   /* Now that breakpoint is removed from breakpoint list, update the
      global location list.  This will remove locations that used to

gdb/fbsd-tdep.c

@@ -637,14 +637,11 @@ fbsd_core_xfer_siginfo (struct gdbarch *gdbarch, gdb_byte *readbuf,
   return len;
 }
 
-static int
+static bool
-find_signalled_thread (struct thread_info *info, void *data)
+find_signalled_thread (struct thread_info *info)
 {
-  if (info->stop_signal () != GDB_SIGNAL_0
+  return (info->stop_signal () != GDB_SIGNAL_0
-      && info->ptid.pid () == inferior_ptid.pid ())
+	  && info->ptid.pid () == inferior_ptid.pid ());
-    return 1;
-
-  return 0;
 }
 
 /* Return a byte_vector containing the contents of a core dump note
@@ -718,7 +715,7 @@ fbsd_make_corefile_notes (struct gdbarch *gdbarch, bfd *obfd, int *note_size)
     signalled_thr = curr_thr;
   else
     {
-      signalled_thr = iterate_over_threads (find_signalled_thread, NULL);
+      signalled_thr = iterate_over_threads (find_signalled_thread);
       if (signalled_thr == NULL)
 	signalled_thr = curr_thr;
     }

gdb/gdbthread.h

@@ -734,8 +734,8 @@ void thread_change_ptid (process_stratum_target *targ,
 
 /* Iterator function to call a user-provided callback function
    once for each known thread.  */
-typedef int (*thread_callback_func) (struct thread_info *, void *);
+typedef gdb::function_view<bool (struct thread_info *)> thread_callback_func;
-extern struct thread_info *iterate_over_threads (thread_callback_func, void *);
+extern struct thread_info *iterate_over_threads (thread_callback_func);
 
 /* Pull in the internals of the inferiors/threads ranges and
    iterators.  Must be done after struct thread_info is defined.  */

gdb/infcmd.c

@@ -530,8 +530,8 @@ starti_command (const char *args, int from_tty)
   run_command_1 (args, from_tty, RUN_STOP_AT_FIRST_INSN);
 } 
 
-static int
+static bool
-proceed_thread_callback (struct thread_info *thread, void *arg)
+proceed_thread_callback (struct thread_info *thread)
 {
   /* We go through all threads individually instead of compressing
      into a single target `resume_all' request, because some threads
@@ -543,15 +543,15 @@ proceed_thread_callback (struct thread_info *thread, void *arg)
      thread stopped until I say otherwise', then we can optimize
      this.  */
   if (thread->state != THREAD_STOPPED)
-    return 0;
+    return false;
 
   if (!thread->inf->has_execution ())
-    return 0;
+    return false;
 
   switch_to_thread (thread);
   clear_proceed_status (0);
   proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
-  return 0;
+  return false;
 }
 
 static void
@@ -608,7 +608,7 @@ continue_1 (int all_threads)
       scoped_disable_commit_resumed disable_commit_resumed
 	("continue all threads in non-stop");
 
-      iterate_over_threads (proceed_thread_callback, nullptr);
+      iterate_over_threads (proceed_thread_callback);
 
       if (current_ui->prompt_state == PROMPT_BLOCKED)
 	{

gdb/infrun.c

@@ -6671,9 +6671,8 @@ restart_threads (struct thread_info *event_thread, inferior *inf)
 /* Callback for iterate_over_threads.  Find a resumed thread that has
    a pending waitstatus.  */
 
-static int
+static bool
-resumed_thread_with_pending_status (struct thread_info *tp,
+resumed_thread_with_pending_status (struct thread_info *tp)
-				    void *arg)
 {
   return tp->resumed () && tp->has_pending_waitstatus ();
 }
@@ -6751,8 +6750,7 @@ finish_step_over (struct execution_control_state *ecs)
       if (ecs->ws.kind () == TARGET_WAITKIND_THREAD_EXITED)
        return 0;
 
-      pending = iterate_over_threads (resumed_thread_with_pending_status,
+      pending = iterate_over_threads (resumed_thread_with_pending_status);
-				      nullptr);
       if (pending != nullptr)
 	{
 	  struct thread_info *tp = ecs->event_thread;

gdb/mi/mi-main.c

@@ -250,15 +250,6 @@ proceed_thread (struct thread_info *thread, int pid)
   proceed ((CORE_ADDR) -1, GDB_SIGNAL_DEFAULT);
 }
 
-static int
-proceed_thread_callback (struct thread_info *thread, void *arg)
-{
-  int pid = *(int *)arg;
-
-  proceed_thread (thread, pid);
-  return 0;
-}
-
 static void
 exec_continue (const char *const *argv, int argc)
 {
@@ -288,7 +279,11 @@ exec_continue (const char *const *argv, int argc)
 	      pid = inf->pid;
 	    }
 
-	  iterate_over_threads (proceed_thread_callback, &pid);
+	  iterate_over_threads ([&] (struct thread_info *thread)
+	    {
+	      proceed_thread (thread, pid);
+	      return false;
+	    });
 	  disable_commit_resumed.reset_and_commit ();
 	}
       else
@@ -341,21 +336,6 @@ mi_cmd_exec_continue (const char *command, const char *const *argv, int argc)
     exec_continue (argv, argc);
 }
 
-static int
-interrupt_thread_callback (struct thread_info *thread, void *arg)
-{
-  int pid = *(int *)arg;
-
-  if (thread->state != THREAD_RUNNING)
-    return 0;
-
-  if (thread->ptid.pid () != pid)
-    return 0;
-
-  target_stop (thread->ptid);
-  return 0;
-}
-
 /* Interrupt the execution of the target.  Note how we must play
    around with the token variables, in order to display the current
    token in the result of the interrupt command, and the previous
@@ -385,7 +365,17 @@ mi_cmd_exec_interrupt (const char *command, const char *const *argv, int argc)
       scoped_disable_commit_resumed disable_commit_resumed
 	("interrupting all threads of thread group");
 
-      iterate_over_threads (interrupt_thread_callback, &inf->pid);
+      iterate_over_threads ([&] (struct thread_info *thread)
+	{
+	  if (thread->state != THREAD_RUNNING)
+	    return false;
+
+	  if (thread->ptid.pid () != inf->pid)
+	    return false;
+
+	  target_stop (thread->ptid);
+	  return false;
+	});
     }
   else
     {
@@ -478,18 +468,6 @@ mi_cmd_exec_run (const char *command, const char *const *argv, int argc)
     }
 }
 
-
-static int
-find_thread_of_process (struct thread_info *ti, void *p)
-{
-  int pid = *(int *)p;
-
-  if (ti->ptid.pid () == pid && ti->state != THREAD_EXITED)
-    return 1;
-
-  return 0;
-}
-
 void
 mi_cmd_target_detach (const char *command, const char *const *argv, int argc)
 {
@@ -528,7 +506,10 @@ mi_cmd_target_detach (const char *command, const char *const *argv, int argc)
 
       /* Pick any thread in the desired process.  Current
 	 target_detach detaches from the parent of inferior_ptid.  */
-      tp = iterate_over_threads (find_thread_of_process, &pid);
+      tp = iterate_over_threads ([&] (struct thread_info *ti)
+	{
+	  return ti->ptid.pid () == pid && ti->state != THREAD_EXITED;
+	});
       if (!tp)
 	error (_("Thread group is empty"));
 
@@ -600,28 +581,6 @@ mi_cmd_thread_info (const char *command, const char *const *argv, int argc)
   print_thread_info (current_uiout, argv[0], -1);
 }
 
-struct collect_cores_data
-{
-  int pid;
-  std::set<int> cores;
-};
-
-static int
-collect_cores (struct thread_info *ti, void *xdata)
-{
-  struct collect_cores_data *data = (struct collect_cores_data *) xdata;
-
-  if (ti->ptid.pid () == data->pid)
-    {
-      int core = target_core_of_thread (ti->ptid);
-
-      if (core != -1)
-	data->cores.insert (core);
-    }
-
-  return 0;
-}
-
 static void
 print_one_inferior (struct inferior *inferior, bool recurse,
 		    const std::set<int> &ids)
@@ -630,7 +589,7 @@ print_one_inferior (struct inferior *inferior, bool recurse,
 
   if (ids.empty () || (ids.find (inferior->pid) != ids.end ()))
     {
-      struct collect_cores_data data;
+      std::set<int> cores;
       ui_out_emit_tuple tuple_emitter (uiout, NULL);
 
       uiout->field_fmt ("id", "i%d", inferior->num);
@@ -646,15 +605,24 @@ print_one_inferior (struct inferior *inferior, bool recurse,
 
       if (inferior->pid != 0)
 	{
-	  data.pid = inferior->pid;
+	  iterate_over_threads ([&] (struct thread_info *ti)
-	  iterate_over_threads (collect_cores, &data);
+	    {
+	      if (ti->ptid.pid () == inferior->pid)
+		{
+		  int core = target_core_of_thread (ti->ptid);
+
+		  if (core != -1)
+		    cores.insert (core);
+		}
+	      return false;
+	    });
 	}
 
-      if (!data.cores.empty ())
+      if (!cores.empty ())
 	{
 	  ui_out_emit_list list_emitter (uiout, "cores");
 
-	  for (int b : data.cores)
+	  for (int b : cores)
 	    uiout->field_signed (NULL, b);
 	}
 

gdb/sol-thread.c

@@ -1108,25 +1108,14 @@ info_solthreads (const char *args, int from_tty)
 		    TD_SIGNO_MASK, TD_THR_ANY_USER_FLAGS);
 }
 
-/* Callback routine used to find a thread based on the TID part of
-   its PTID.  */
-
-static int
-thread_db_find_thread_from_tid (struct thread_info *thread, void *data)
-{
-  ULONGEST *tid = (ULONGEST *) data;
-
-  if (thread->ptid.tid () == *tid)
-    return 1;
-
-  return 0;
-}
-
 ptid_t
 sol_thread_target::get_ada_task_ptid (long lwp, ULONGEST thread)
 {
-  struct thread_info *thread_info =
+  struct thread_info *thread_info
-    iterate_over_threads (thread_db_find_thread_from_tid, &thread);
+    = iterate_over_threads ([&] (struct thread_info *thread)
+       {
+	 return thread->ptid.tid () == thread;
+       });
 
   if (thread_info == NULL)
     {

gdb/thread.c

@@ -602,11 +602,10 @@ find_thread_by_handle (gdb::array_view<const gdb_byte> handle,
  */
 
 struct thread_info *
-iterate_over_threads (int (*callback) (struct thread_info *, void *),
+iterate_over_threads (gdb::function_view<bool (struct thread_info *)> callback)
-		      void *data)
 {
   for (thread_info *tp : all_threads_safe ())
-    if ((*callback) (tp, data))
+    if (callback (tp))
       return tp;
 
   return NULL;