gdbsupport/task-group.cc

   1 /* Task group
   2
   3    Copyright (C) 2023-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "task-group.h"
  21 #include "thread-pool.h"
  22
  23 namespace gdb
  24 {
  25
  26 class task_group::impl : public std::enable_shared_from_this<task_group::impl>
  27 {
  28 public:
  29
  30   explicit impl (std::function<void ()> &&done)
  31     : m_done (std::move (done))
  32   { }
  33   DISABLE_COPY_AND_ASSIGN (impl);
  34
  35   ~impl ()
  36   {
  37     if (m_started)
  38       m_done ();
  39   }
  40
  41   /* Add a task to the task group.  */
  42   void add_task (std::function<void ()> &&task)
  43   {
  44     m_tasks.push_back (std::move (task));
  45   };
  46
  47   /* Start this task group.  */
  48   void start ();
  49
  50   /* True if started.  */
  51   bool m_started = false;
  52   /* The tasks.  */
  53   std::vector<std::function<void ()>> m_tasks;
  54   /* The 'done' function.  */
  55   std::function<void ()> m_done;
  56 };
  57
  58 void
  59 task_group::impl::start ()
  60 {
  61   std::shared_ptr<impl> shared_this = shared_from_this ();
  62   m_started = true;
  63   for (size_t i = 0; i < m_tasks.size (); ++i)
  64     {
  65       gdb::thread_pool::g_thread_pool->post_task ([=] ()
  66       {
  67         /* Be sure to capture a shared reference here.  */
  68         shared_this->m_tasks[i] ();
  69       });
  70     }
  71 }
  72
  73 task_group::task_group (std::function<void ()> &&done)
  74   : m_task (new impl (std::move (done)))
  75 {
  76 }
  77
  78 void
  79 task_group::add_task (std::function<void ()> &&task)
  80 {
  81   gdb_assert (m_task != nullptr);
  82   m_task->add_task (std::move (task));
  83 }
  84
  85 void
  86 task_group::start ()
  87 {
  88   gdb_assert (m_task != nullptr);
  89   m_task->start ();
  90   m_task.reset ();
  91 }
  92
  93 } /* namespace gdb */