Use separate thread for saving session data.

src/core/dht_manager.cc

@@ -17,6 +17,7 @@
 #include "globals.h"
 #include "manager.h"
 #include "rpc/parse_commands.h"
+#include "session/session_manager.h"
 
 #define LT_LOG(log_fmt, ...)                                            \
   lt_log_print_subsystem(torrent::LOG_DHT_CONTROLLER, "dht_manager", log_fmt, __VA_ARGS__);
@@ -35,13 +36,13 @@ DhtManager::~DhtManager() {
 
 void
 DhtManager::load_dht_cache() {
-  if (m_start == dht_disable || !control->core()->download_store()->is_enabled()) {
+  if (m_start == dht_disable || !session_thread::manager()->is_used()) {
     LT_LOG("ignoring cache file", 0);
     return;
   }
 
-  std::string cache_filename = control->core()->download_store()->path() + "rtorrent.dht_cache";
-  std::fstream cache_stream(cache_filename.c_str(), std::ios::in | std::ios::binary);
+  auto cache_filename = session_thread::manager()->path() + "rtorrent.dht_cache";
+  auto cache_stream   = std::fstream(cache_filename.c_str(), std::ios::in | std::ios::binary);
 
   torrent::Object cache = torrent::Object::create_map();
 
@@ -115,14 +116,15 @@ DhtManager::stop_dht() {
 
 void
 DhtManager::save_dht_cache() {
-  if (!control->core()->download_store()->is_enabled())
+  if (!session_thread::manager()->is_used())
     return;
+
   if (!torrent::runtime::network_manager()->is_dht_valid())
     return;
 
-  std::string filename = control->core()->download_store()->path() + "rtorrent.dht_cache";
-  std::string filename_tmp = filename + ".new";
-  std::fstream cache_file(filename_tmp.c_str(), std::ios::out | std::ios::trunc);
+  auto filename     = session_thread::manager()->path() + "rtorrent.dht_cache";
+  auto filename_tmp = filename + ".new";
+  auto cache_file   = std::fstream(filename_tmp.c_str(), std::ios::out | std::ios::trunc);
 
   if (!cache_file.is_open())
     return;

src/core/download_store.cc

@@ -5,6 +5,7 @@
 #include <fstream>
 #include <stdio.h>
 #include <fcntl.h>
+#include <sstream>
 #include <unistd.h>
 #include <rak/error_number.h>
 #include <rak/path.h>
@@ -16,104 +17,17 @@
 #include <torrent/rate.h>
 #include <torrent/object_stream.h>
 
-#include "utils/directory.h"
-
 #include "download.h"
 #include "download_store.h"
 #include "rpc/parse_commands.h"
+#include "session/session_manager.h"
+#include "utils/directory.h"
 
 namespace core {
 
-void
-DownloadStore::enable(bool lock) {
-  if (is_enabled())
-    throw torrent::input_error("Session directory already enabled.");
-
-  if (m_path.empty())
-    return;
-
-  if (lock)
-    m_lockfile.set_path(m_path + "rtorrent.lock");
-  else
-    m_lockfile.set_path(std::string());
-
-  if (!m_lockfile.try_lock()) {
-    if (rak::error_number::current().is_bad_path())
-      throw torrent::input_error("Could not lock session directory: \"" + m_path + "\", " + rak::error_number::current().c_str());
-    else
-      throw torrent::input_error("Could not lock session directory: \"" + m_path + "\", held by \"" + m_lockfile.locked_by_as_string() + "\".");
-  }
-}
-
-void
-DownloadStore::disable() {
-  if (!is_enabled())
-    return;
-
-  m_lockfile.unlock();
-}
-
-void
-DownloadStore::set_path(const std::string& path) {
-  if (is_enabled())
-    throw torrent::input_error("Tried to change session directory while it is enabled.");
-
-  if (!path.empty() && *path.rbegin() != '/')
-    m_path = rak::path_expand(path + '/');
-  else
-    m_path = rak::path_expand(path);
-}
-
-bool
-DownloadStore::write_bencode(const std::string& filename, const torrent::Object& obj, uint32_t skip_mask) {
-  int fd;
-  torrent::Object tmp;
-  std::fstream output(filename.c_str(), std::ios::out | std::ios::trunc);
-
-  if (!output.is_open())
-    goto download_store_save_error;
-
-  torrent::object_write_bencode(&output, &obj, skip_mask);
-
-  if (!output.good())
-    goto download_store_save_error;
-
-  output.close();
-
-  // Test the new file, to ensure it is a valid bencode string.
-  output.open(filename.c_str(), std::ios::in);
-  output >> tmp;
-
-  if (!output.good())
-    goto download_store_save_error;
-
-  output.close();
-
-  // Ensure that the new file is actually written to the disk
-  fd = ::open(filename.c_str(), O_WRONLY);
-  if (fd < 0)
-    goto download_store_save_error;
-
-  if (rpc::call_command_value("system.files.session.fdatasync")) {
-#ifdef __APPLE__
-    fsync(fd);
-#else
-    fdatasync(fd);
-#endif
-  }
-
-  ::close(fd);
-
-  return true;
-
-download_store_save_error:
-  output.close();
-  return false;
-}
-
 bool
 DownloadStore::save(Download* d, int flags) {
-  if (!is_enabled())
+  if (!session_thread::manager()->is_used())
     return true;
 
   torrent::Object* resume_base   = &d->download()->bencode()->get_key("libtorrent_resume");
@@ -137,30 +51,38 @@ DownloadStore::save(Download* d, int flags) {
   resume_base->set_flags(torrent::Object::flag_session_data);
   rtorrent_base->set_flags(torrent::Object::flag_session_data);
 
-  std::string base_filename = create_filename(d);
+  auto download_stream = std::unique_ptr<std::stringstream>();
+  auto resume_stream   = std::make_unique<std::stringstream>();
+  auto rtorrent_stream = std::make_unique<std::stringstream>();
 
-  if (!write_bencode(base_filename + ".libtorrent_resume.new", *resume_base, 0) ||
-      !write_bencode(base_filename + ".rtorrent.new", *rtorrent_base, 0))
+  if (!(flags & flag_skip_static)) {
+    download_stream = std::make_unique<std::stringstream>();
+    torrent::object_write_bencode(&*download_stream, d->bencode(), torrent::Object::flag_session_data);
+
+    if (!download_stream->good())
+      return false;
+  }
+
+  torrent::object_write_bencode(&*resume_stream, resume_base, 0);
+
+  // TODO: Add logging.
+  if (!resume_stream->good())
     return false;
 
-  ::rename((base_filename + ".libtorrent_resume.new").c_str(), (base_filename + ".libtorrent_resume").c_str());
-  ::rename((base_filename + ".rtorrent.new").c_str(), (base_filename + ".rtorrent").c_str());
+  torrent::object_write_bencode(&*rtorrent_stream, rtorrent_base, 0);
 
-  if (!(flags & flag_skip_static) &&
-      write_bencode(base_filename + ".new", *d->bencode(), torrent::Object::flag_session_data))
-    ::rename((base_filename + ".new").c_str(), base_filename.c_str());
+  if (!rtorrent_stream->good())
+    return false;
 
+  auto base_filename = create_filename(d);
+
+  session_thread::manager()->save_download(d, base_filename, std::move(download_stream), std::move(resume_stream), std::move(rtorrent_stream));
   return true;
 }
 
 void
 DownloadStore::remove(Download* d) {
-  if (!is_enabled())
-    return;
-
-  ::unlink((create_filename(d) + ".libtorrent_resume").c_str());
-  ::unlink((create_filename(d) + ".rtorrent").c_str());
-  ::unlink(create_filename(d).c_str());
+  session_thread::manager()->remove_download(d, create_filename(d));
 }
 
 // This also needs to check that it isn't a directory.
@@ -171,13 +93,13 @@ not_correct_format(const utils::directory_entry& entry) {
 
 utils::Directory
 DownloadStore::get_formated_entries() {
-  if (!is_enabled())
+  if (!session_thread::manager()->is_used())
     return utils::Directory();
 
-  utils::Directory d(m_path);
+  utils::Directory d(session_thread::manager()->path());
 
   if (!d.update(utils::Directory::update_hide_dot))
-    throw torrent::storage_error("core::DownloadStore::update() could not open directory \"" + m_path + "\"");
+    throw torrent::storage_error("core::DownloadStore::update() could not open session directory: " + session_thread::manager()->path());
 
   d.erase(std::remove_if(d.begin(), d.end(), [&](const utils::directory_entry& entry) { return not_correct_format(entry); }), d.end());
 
@@ -199,7 +121,7 @@ DownloadStore::is_correct_format(const std::string& f) {
 
 std::string
 DownloadStore::create_filename(Download* d) {
-  return m_path + rak::transform_hex(d->info()->hash().begin(), d->info()->hash().end()) + ".torrent";
+  return session_thread::manager()->path() + rak::transform_hex(d->info()->hash().begin(), d->info()->hash().end()) + ".torrent";
 }
 
 }

src/core/download_store.h

@@ -2,8 +2,7 @@
 #define RTORRENT_CORE_DOWNLOAD_STORE_H
 
 #include <string>
-
-#include "utils/lockfile.h"
+#include <torrent/common.h>
 
 namespace utils {
   class Directory;
@@ -17,14 +16,6 @@ class DownloadStore {
 public:
   static const int flag_skip_static = 0x1;
 
-  bool                is_enabled()                            { return m_lockfile.is_locked(); }
-
-  void                enable(bool lock);
-  void                disable();
-
-  const std::string&  path() const                            { return m_path; }
-  void                set_path(const std::string& path);
-
   bool                save(Download* d, int flags);
   bool                save_full(Download* d)   { return save(d, 0); }
   bool                save_resume(Download* d) { return save(d, flag_skip_static); }
@@ -37,11 +28,6 @@ public:
 
 private:
   std::string         create_filename(Download* d);
-
-  bool                write_bencode(const std::string& filename, const torrent::Object& obj, uint32_t skip_mask);
-
-  std::string         m_path;
-  utils::Lockfile     m_lockfile;
 };
 
 }