Change __sync_* to std::atomic and remove unneeded code

src/thread_disk.cc

@@ -1,39 +1,3 @@
-// libTorrent - BitTorrent library
-// Copyright (C) 2005-2011, Jari Sundell
-//
-// 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
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-//
-// In addition, as a special exception, the copyright holders give
-// permission to link the code of portions of this program with the
-// OpenSSL library under certain conditions as described in each
-// individual source file, and distribute linked combinations
-// including the two.
-//
-// You must obey the GNU General Public License in all respects for
-// all of the code used other than OpenSSL.  If you modify file(s)
-// with this exception, you may extend this exception to your version
-// of the file(s), but you are not obligated to do so.  If you do not
-// wish to do so, delete this exception statement from your version.
-// If you delete this exception statement from all source files in the
-// program, then also delete it here.
-//
-// Contact:  Jari Sundell <[email protected]>
-//
-//           Skomakerveien 33
-//           3185 Skoppum, NORWAY
-
 #include "config.h"
 
 #include <rak/timer.h>
@@ -67,7 +31,7 @@ thread_disk::call_events() {
     if ((m_flags & flag_did_shutdown))
       throw internal_error("Already trigged shutdown.");
 
-    __sync_or_and_fetch(&m_flags, flag_did_shutdown);
+    m_flags |= flag_did_shutdown;
     throw shutdown_exception();
   }
 

src/thread_main.cc

@@ -1,39 +1,3 @@
-// libTorrent - BitTorrent library
-// Copyright (C) 2005-2011, Jari Sundell
-//
-// 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
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-//
-// In addition, as a special exception, the copyright holders give
-// permission to link the code of portions of this program with the
-// OpenSSL library under certain conditions as described in each
-// individual source file, and distribute linked combinations
-// including the two.
-//
-// You must obey the GNU General Public License in all respects for
-// all of the code used other than OpenSSL.  If you modify file(s)
-// with this exception, you may extend this exception to your version
-// of the file(s), but you are not obligated to do so.  If you do not
-// wish to do so, delete this exception statement from your version.
-// If you delete this exception statement from all source files in the
-// program, then also delete it here.
-//
-// Contact:  Jari Sundell <[email protected]>
-//
-//           Skomakerveien 33
-//           3185 Skoppum, NORWAY
-
 #include "config.h"
 
 #include <rak/timer.h>

src/thread_main.h

@@ -1,39 +1,3 @@
-// libTorrent - BitTorrent library
-// Copyright (C) 2005-2011, Jari Sundell
-//
-// 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
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-//
-// In addition, as a special exception, the copyright holders give
-// permission to link the code of portions of this program with the
-// OpenSSL library under certain conditions as described in each
-// individual source file, and distribute linked combinations
-// including the two.
-//
-// You must obey the GNU General Public License in all respects for
-// all of the code used other than OpenSSL.  If you modify file(s)
-// with this exception, you may extend this exception to your version
-// of the file(s), but you are not obligated to do so.  If you do not
-// wish to do so, delete this exception statement from your version.
-// If you delete this exception statement from all source files in the
-// program, then also delete it here.
-//
-// Contact:  Jari Sundell <[email protected]>
-//
-//           Skomakerveien 33
-//           3185 Skoppum, NORWAY
-
 #ifndef LIBTORRENT_THREAD_MAIN_H
 #define LIBTORRENT_THREAD_MAIN_H
 

src/torrent/poll_epoll.cc

@@ -1,39 +1,3 @@
-// libTorrent - BitTorrent library
-// Copyright (C) 2005-2011, Jari Sundell
-//
-// 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
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-//
-// In addition, as a special exception, the copyright holders give
-// permission to link the code of portions of this program with the
-// OpenSSL library under certain conditions as described in each
-// individual source file, and distribute linked combinations
-// including the two.
-//
-// You must obey the GNU General Public License in all respects for
-// all of the code used other than OpenSSL.  If you modify file(s)
-// with this exception, you may extend this exception to your version
-// of the file(s), but you are not obligated to do so.  If you do not
-// wish to do so, delete this exception statement from your version.
-// If you delete this exception statement from all source files in the
-// program, then also delete it here.
-//
-// Contact:  Jari Sundell <[email protected]>
-//
-//           Skomakerveien 33
-//           3185 Skoppum, NORWAY
-
 #include "config.h"
 
 #include <cerrno>
@@ -203,13 +167,11 @@ PollEPoll::do_poll(int64_t timeout_usec, int flags) {
 
   if (!(flags & poll_worker_thread)) {
     thread_base::release_global_lock();
-    thread_base::entering_main_polling();
   }
 
   int status = poll((timeout.usec() + 999) / 1000);
 
   if (!(flags & poll_worker_thread)) {
-    thread_base::leaving_main_polling();
     thread_base::acquire_global_lock();
   }
 

src/torrent/poll_kqueue.cc

@@ -1,39 +1,3 @@
-// libTorrent - BitTorrent library
-// Copyright (C) 2005-2011, Jari Sundell
-//
-// 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
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-//
-// In addition, as a special exception, the copyright holders give
-// permission to link the code of portions of this program with the
-// OpenSSL library under certain conditions as described in each
-// individual source file, and distribute linked combinations
-// including the two.
-//
-// You must obey the GNU General Public License in all respects for
-// all of the code used other than OpenSSL.  If you modify file(s)
-// with this exception, you may extend this exception to your version
-// of the file(s), but you are not obligated to do so.  If you do not
-// wish to do so, delete this exception statement from your version.213
-// If you delete this exception statement from all source files in the
-// program, then also delete it here.
-//
-// Contact:  Jari Sundell <[email protected]>
-//
-//           Skomakerveien 33
-//           3185 Skoppum, NORWAY
-
 #include "config.h"
 
 #include <cerrno>
@@ -262,13 +226,11 @@ PollKQueue::do_poll(int64_t timeout_usec, int flags) {
 
   if (!(flags & poll_worker_thread)) {
     thread_base::release_global_lock();
-    thread_base::entering_main_polling();
   }
 
   int status = poll((timeout.usec() + 999) / 1000);
 
   if (!(flags & poll_worker_thread)) {
-    thread_base::leaving_main_polling();
     thread_base::acquire_global_lock();
   }
 

src/torrent/poll_select.cc

@@ -1,39 +1,3 @@
-// libTorrent - BitTorrent library
-// Copyright (C) 2005-2011, Jari Sundell
-//
-// 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
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-//
-// In addition, as a special exception, the copyright holders give
-// permission to link the code of portions of this program with the
-// OpenSSL library under certain conditions as described in each
-// individual source file, and distribute linked combinations
-// including the two.
-//
-// You must obey the GNU General Public License in all respects for
-// all of the code used other than OpenSSL.  If you modify file(s)
-// with this exception, you may extend this exception to your version
-// of the file(s), but you are not obligated to do so.  If you do not
-// wish to do so, delete this exception statement from your version.
-// If you delete this exception statement from all source files in the
-// program, then also delete it here.
-//
-// Contact:  Jari Sundell <[email protected]>
-//
-//           Skomakerveien 33
-//           3185 Skoppum, NORWAY
-
 #include "config.h"
 
 #include <algorithm>
@@ -243,14 +207,12 @@ PollSelect::do_poll(int64_t timeout_usec, int flags) {
   timeval t = timeout.tval();
 
   if (!(flags & poll_worker_thread)) {
-    thread_base::entering_main_polling();
     thread_base::release_global_lock();
   }
 
   int status = select(maxFd + 1, read_set, write_set, error_set, &t);
 
   if (!(flags & poll_worker_thread)) {
-    thread_base::leaving_main_polling();
     thread_base::acquire_global_lock();
   }
 
@@ -273,7 +235,7 @@ log_poll_open(Event* event) {
 
   if (log_fd == -1) {
     snprintf(buffer, 256, LT_LOG_POLL_OPEN, getpid());
-    
+
     if ((log_fd = open(buffer, O_WRONLY | O_CREAT | O_TRUNC)) == -1)
       throw internal_error("Could not open poll open log file.");
   }

src/torrent/utils/signal_bitfield.cc

@@ -1,45 +1,46 @@
 #include "config.h"
 
-#include "torrent/exceptions.h"
-
 #include "signal_bitfield.h"
 
+#include <cassert>
+#include "torrent/exceptions.h"
+
 namespace torrent {
 
 const unsigned int signal_bitfield::max_size;
 
 // Only the thread owning this signal bitfield should add signals.
 unsigned int
 signal_bitfield::add_signal(slot_type slot) {
+  if (m_thread_id != std::this_thread::get_id())
+    throw internal_error("signal_bitfield::add_signal(...): Only the owning thread can add signals.");
+
   if (m_size >= max_size)
     throw internal_error("signal_bitfield::add_signal(...): No more available slots.");
 
   if (!slot)
     throw internal_error("signal_bitfield::add_signal(...): Cannot add empty slot.");
 
-  unsigned int index = m_size;
-  __sync_add_and_fetch(&m_size, 1);
-
+  unsigned int index = m_size++;
   m_slots[index] = slot;
+
   return index;
 }
 
 void
 signal_bitfield::work() {
-  bitfield_type bitfield;
+  // static_assert(std::atomic<bitfield_type>()::is_always_lock_free(), "signal_bitfield::work(...): Bitfield type is not lockfree.");
 
-  while (!__sync_bool_compare_and_swap(&m_bitfield, (bitfield = m_bitfield), 0))
-    ; // Do nothing.
+  if (m_thread_id != std::this_thread::get_id())
+    throw internal_error("signal_bitfield::work(...): Only the owning thread can do work for signal bitfields.");
 
-  unsigned int i = 0;
+  auto bitfield = m_bitfield.exchange(0);
 
-  while (bitfield) {
+  for (unsigned int i = 0; bitfield != 0 && i < m_size; i++) {
     if ((bitfield & (1 << i))) {
       m_slots[i]();
       bitfield = bitfield & ~(1 << i);
     }
-
-    i++;
   }
 }