Removed old LOG_TORRENT_* categories and replaced with LOG_TORRENT_{DEBUG,EVENTS}.

Keep the change to d, f, p and t multicalls. Parse each column lazily on first use and evaluate it through rpc::call_object, preserving per-target argument expansion.

Compared unpatched and patched builds on macOS: output was byte-identical across the test harness, including an erase-mid-call check.

configure.ac

@@ -1,6 +1,6 @@
 m4_pattern_allow([PKG_CHECK_EXISTS])
 
-AC_INIT([rtorrent],[0.16.24],[sundell.software@gmail.com])
+AC_INIT([rtorrent],[0.16.25],[sundell.software@gmail.com])
 
 AC_CONFIG_HEADERS([config.h])
 AC_CONFIG_MACRO_DIRS([scripts])
@@ -14,7 +14,7 @@ AX_CXX_COMPILE_STDCXX(20, noext, mandatory)
 
 PKG_PROG_PKG_CONFIG
 
-AC_DEFINE([API_VERSION], [28], [api version])
+AC_DEFINE([API_VERSION], [29], [api version])
 
 RAK_CHECK_CFLAGS
 RAK_CHECK_CXXFLAGS
@@ -49,7 +49,7 @@ fi
 
 PKG_CHECK_MODULES([CPPUNIT], [cppunit],, [no_cppunit="yes"])
 PKG_CHECK_MODULES([ZLIB], [zlib])
-PKG_CHECK_MODULES([DEPENDENCIES], [libtorrent >= 0.16.24])
+PKG_CHECK_MODULES([DEPENDENCIES], [libtorrent >= 0.16.25])
 
 AC_LANG_PUSH(C++)
 TORRENT_WITH_XMLRPC_C

src/command_download.cc

@@ -107,7 +107,7 @@ apply_d_change_link(core::Download* download, const torrent::Object::list_type&
   switch (changeType) {
   case 0:
     if (symlink(target.c_str(), link.c_str()) == -1)
-      lt_log_print(torrent::LOG_TORRENT_WARN, "create_link failed: %s", std::strerror(errno));
+      lt_log_print(torrent::LOG_TORRENT_DEBUG, "create_link failed: %s", std::strerror(errno));
 
     break;
 
@@ -117,7 +117,7 @@ apply_d_change_link(core::Download* download, const torrent::Object::list_type&
     errno = 0;
 
     if (!fileStat.update_link(link) || !fileStat.is_link() || unlink(link.c_str()) == -1)
-      lt_log_print(torrent::LOG_TORRENT_WARN, "delete_link failed: %s", std::strerror(errno));
+      lt_log_print(torrent::LOG_TORRENT_DEBUG, "delete_link failed: %s", std::strerror(errno));
 
     break;
   }
@@ -135,7 +135,7 @@ apply_d_delete_tied(core::Download* download) {
   if (tie.empty())
     return torrent::Object();
 
-  if (::unlink(expand_path(tie).c_str()) == -1)
+  if (unlink(expand_path(tie).c_str()) == -1)
     control->core()->push_log_std("Could not unlink tied file: " + std::string(std::strerror(errno)));
 
   rpc::call_command("d.tied_to_file.set", std::string(), rpc::make_target(download));
@@ -293,7 +293,7 @@ apply_d_add_peer(core::Download* download, const std::string& arg) {
   // Currently discarding SOCK_STREAM.
   torrent::this_thread::resolver()->resolve_preferred(callback_id, host, AF_UNSPEC, AF_INET, [download, port](torrent::c_sa_shared_ptr sa, int err) {
       if (sa == nullptr) {
-        lt_log_print(torrent::LOG_TORRENT_WARN, "could not resolve hostname for added peer: %s", gai_strerror(err));
+        lt_log_print(torrent::LOG_TORRENT_DEBUG, "could not resolve hostname for added peer: %s", gai_strerror(err));
         return;
       }
 
@@ -334,6 +334,11 @@ f_multicall(core::Download* download, const torrent::Object::list_type& args) {
 
   bool use_regex = true;
 
+  rpc::preparsed_commands commands([&args](auto& cmds) {
+    for (auto cItr = ++args.begin(); cItr != args.end(); ++cItr)
+      cmds.push_back(rpc::parse_command_object(cItr->as_string()));
+  });
+
   if (args.front().is_list())
     for (const auto& o : args.front().as_list())
       regex_list.push_back(o.as_string_c());
@@ -349,10 +354,10 @@ f_multicall(core::Download* download, const torrent::Object::list_type& args) {
 
     torrent::Object::list_type& row = result.insert(result.end(), torrent::Object::create_list())->as_list();
 
-    for (torrent::Object::list_const_iterator cItr = ++args.begin(); cItr != args.end(); cItr++) {
-      const std::string& cmd = cItr->as_string();
-      row.push_back(rpc::parse_command(rpc::make_target(file.get()), cmd.c_str(), cmd.c_str() + cmd.size()).first);
-    }
+    // Defer parsing until a file actually matches the multicall selection.
+    commands.prepare_if_needed();
+    for (auto& itr : commands)
+      row.push_back(rpc::call_object(itr, rpc::make_target(file.get())));
   }
 
   return resultRaw;
@@ -372,6 +377,11 @@ t_multicall(core::Download* download, const torrent::Object::list_type& args) {
   auto  result_raw = torrent::Object::create_list();
   auto& result     = result_raw.as_list();
 
+  rpc::preparsed_commands commands([&args](auto& cmds) {
+    for (auto cItr = ++args.begin(); cItr != args.end(); ++cItr)
+      cmds.push_back(rpc::parse_command_object(cItr->as_string()));
+  });
+
   for (uint32_t idx = 0, last = download->tracker_list_size(); idx < last; idx++) {
     auto& row     = result.insert(result.end(), torrent::Object::create_list())->as_list();
     auto  tracker = download->tracker_controller().at(idx);
@@ -379,11 +389,10 @@ t_multicall(core::Download* download, const torrent::Object::list_type& args) {
     if (!tracker.is_valid())
       continue;
 
-    for (auto cItr = ++args.begin(); cItr != args.end(); cItr++) {
-      auto& cmd = cItr->as_string();
-
-      row.push_back(rpc::parse_command(rpc::make_target(&tracker), cmd.c_str(), cmd.c_str() + cmd.size()).first);
-    }
+    // Do not parse columns when there are no valid tracker targets.
+    commands.prepare_if_needed();
+    for (auto& itr : commands)
+      row.push_back(rpc::call_object(itr, rpc::make_target(&tracker)));
   }
 
   return result_raw;
@@ -405,13 +414,18 @@ p_multicall(core::Download* download, const torrent::Object::list_type& args) {
   auto*      connection_list = download->connection_list();
   const auto change_counter  = connection_list->change_counter();
 
+  rpc::preparsed_commands commands([&args](auto& cmds) {
+    for (auto cItr = ++args.begin(); cItr != args.end(); ++cItr)
+      cmds.push_back(rpc::parse_command_object(cItr->as_string()));
+  });
+
   for (const auto& connection : *connection_list) {
     torrent::Object::list_type& row = result.insert(result.end(), torrent::Object::create_list())->as_list();
 
-    for (auto cItr = ++args.begin(); cItr != args.end(); cItr++) {
-      const std::string& cmd = cItr->as_string();
-
-      row.push_back(rpc::parse_command(rpc::make_target(connection), cmd.c_str(), cmd.c_str() + cmd.size()).first);
+    // Prepare only after a peer exists, preserving empty-list laziness.
+    commands.prepare_if_needed();
+    for (auto& itr : commands) {
+      row.push_back(rpc::call_object(itr, rpc::make_target(connection)));
 
       // Erasing a peer frees it and swaps the last element into its place, so
       // neither this peer nor the iteration survives a change to the list.

src/command_events.cc

@@ -169,7 +169,7 @@ void apply_try_import(const std::string& path) { if (!rpc::parse_command_file(pa
 
 torrent::Object
 apply_close_low_diskspace(int64_t arg, uint32_t skip_priority) {
-  bool closed = false;
+  int closed{};
 
   torrent::FileList::cache_list cache;
 
@@ -186,11 +186,11 @@ apply_close_low_diskspace(int64_t arg, uint32_t skip_priority) {
     download->set_hash_failed(true);
     download->set_message(std::string("Low diskspace."));
 
-    closed = true;
+    closed++;
   }
 
-  if (closed)
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Closed torrents due to low diskspace.");
+  if (closed != 0)
+    lt_log_print(torrent::LOG_TORRENT_EVENTS, "closed torrents due to low diskspace : count:%i", closed);
 
   return torrent::Object();
 }
@@ -247,20 +247,26 @@ d_multicall(const torrent::Object::list_type& args) {
   torrent::Object             resultRaw = torrent::Object::create_list();
   torrent::Object::list_type& result = resultRaw.as_list();
 
+  rpc::preparsed_commands commands([&args](auto& cmds) {
+    for (auto cItr = ++args.begin(); cItr != args.end(); ++cItr)
+      cmds.push_back(rpc::parse_command_object(cItr->as_string()));
+  });
+
   for (const auto& download : dlist) {
     if (download.use_count() == 1)
       continue;
 
     torrent::Object::list_type& row = result.insert(result.end(), torrent::Object::create_list())->as_list();
 
-    for (torrent::Object::list_const_iterator cItr = ++args.begin(); cItr != args.end(); cItr++) {
+    // Skip parsing if there are no usable download targets in the view.
+    commands.prepare_if_needed();
+    for (auto& itr : commands) {
       // A command may erase this download, which destroys the torrent object it
       // wraps; the list dropping its reference is what tells us.
       if (download.use_count() == 1)
         break;
 
-      auto& cmd = cItr->as_string();
-      row.push_back(rpc::parse_command(rpc::make_target(download), cmd.c_str(), cmd.c_str() + cmd.size()).first);
+      row.push_back(rpc::call_object(itr, rpc::make_target(download)));
     }
   }
 

src/command_groups.cc

@@ -20,9 +20,6 @@
 // For cg_d_group.
 #include "core/download.h"
 
-#define LT_LOG_SUBSYSTEM(log_fmt, ...)                                  \
-  lt_log_print_subsystem(torrent::LOG_TORRENT_INFO, "choke_queue", log_fmt, __VA_ARGS__);
-
 // A hack to allow testing of the new choke_group API without the
 // working parts present.
 #define USE_CHOKE_GROUP 0
@@ -207,7 +204,7 @@ apply_cg_index_of(const std::string& arg) {
 
 torrent::Object
 apply_cg_all_update_balance(bool is_up) {
-  LT_LOG_SUBSYSTEM("apply update balance: hack is_up:%i", (int)is_up);
+  lt_log_print(torrent::LOG_TORRENT_DEBUG, "choke_queue : applying update balance : is_up:%i", (int)is_up);
 
   for (const auto& itr : cg_list_hack) {
     if (is_up)

src/command_system.cc

@@ -88,6 +88,8 @@ initialize_command_system() {
 
   CMD_ANY         ("system.file_name.replace_slash",         [](auto, auto)        { return torrent::runtime::client_config()->file_name_replace_slash(); });
   CMD_ANY_STRING_V("system.file_name.replace_slash.set",     [](auto, auto& str)   { return torrent::runtime::client_config()->set_file_name_replace_slash(str); });
+  CMD_ANY         ("system.file_name.allow_legacy_utf8",     [](auto, auto)        { return torrent::runtime::client_config()->file_name_allow_legacy_utf8(); });
+  CMD_ANY_VALUE_V ("system.file_name.allow_legacy_utf8.set", [](auto, auto& value) { return torrent::runtime::client_config()->set_file_name_allow_legacy_utf8(value); });
 
   CMD_ANY         ("system.file_status_cache.size",      [](auto, auto)      { return control->core()->file_status_cache()->size(); });
   CMD_ANY_V       ("system.file_status_cache.prune",     [](auto, auto)      { return control->core()->file_status_cache()->prune(); });
@@ -167,10 +169,13 @@ initialize_command_system() {
   rpc::rpc.mark_safe("system.time");
   rpc::rpc.mark_safe("system.time_seconds");
   rpc::rpc.mark_safe("system.time_usec");
+  rpc::rpc.mark_safe("system.torrent_name.use_sanitized");
   rpc::rpc.mark_safe("system.file.allocate");
   rpc::rpc.mark_safe("system.file.max_size");
   rpc::rpc.mark_safe("system.file.split_size");
   rpc::rpc.mark_safe("system.file.split_suffix");
+  rpc::rpc.mark_safe("system.file_name.replace_slash");
+  rpc::rpc.mark_safe("system.file_name.allow_legacy_utf8");
 
   rpc::rpc.mark_safe("system.sockets.size");
   rpc::rpc.mark_safe("system.sockets.max_size");

src/core/download_list.cc

@@ -29,6 +29,11 @@
 #include "session/session_manager.h"
 #include "ui/root.h"
 
+#define LT_LOG_DOWNLOAD_DEBUG(log_fmt, ...)                             \
+  lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, download->info()->hash(), "download_list : " log_fmt, __VA_ARGS__);
+#define LT_LOG_DOWNLOAD_EVENTS(log_fmt, ...)                             \
+  lt_log_print_info(torrent::LOG_TORRENT_EVENTS, download->info(), "download_list", log_fmt, __VA_ARGS__);
+
 #define DL_TRIGGER_EVENT(download, event_name)                          \
   rpc::commands.call_catch(event_name, rpc::make_target(download), torrent::Object(), "Event '" event_name "' failed: ");
 
@@ -109,7 +114,7 @@ DownloadList::create(torrent::Object* obj, uint32_t tracker_key, bool printLog)
 
   } catch (torrent::local_error& e) {
     if (printLog)
-      lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not create download: %s", e.what());
+      lt_log_print(torrent::LOG_TORRENT_EVENTS, "download_list : could not create download : %s", e.what());
 
     delete obj;
 
@@ -135,7 +140,7 @@ DownloadList::create(std::istream* str, uint32_t tracker_key, bool printLog) {
       delete object;
 
       if (printLog)
-        lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not create download, the input is not a valid torrent.");
+        lt_log_print(torrent::LOG_TORRENT_EVENTS, "download_list : could not create download : invalid or incomplete bencode data");
 
       return NULL;
     }
@@ -146,7 +151,7 @@ DownloadList::create(std::istream* str, uint32_t tracker_key, bool printLog) {
     delete object;
 
     if (printLog)
-      lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not create download: %s", e.what());
+      lt_log_print(torrent::LOG_TORRENT_EVENTS, "download_list : could not create download : %s", e.what());
 
     return NULL;
   }
@@ -160,7 +165,7 @@ DownloadList::iterator
 DownloadList::insert(Download* download) {
   iterator itr = base_type::insert(end(), std::shared_ptr<Download>(download));
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Inserting download.");
+  LT_LOG_DOWNLOAD_DEBUG("inserting download", 0);
 
   try {
     (*itr)->data()->slot_initial_hash()        = std::bind(&DownloadList::hash_done, this, download);
@@ -200,7 +205,7 @@ DownloadList::erase(iterator itr) {
 
   (*itr)->set_erasing();
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, (*itr)->info(), "download_list", "Erasing download.");
+  lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, (*itr)->info()->hash(), "download_list : removing download");
 
   // Makes sure close doesn't restart hashing of this download.
   (*itr)->set_hash_failed(true);
@@ -228,7 +233,7 @@ DownloadList::open(Download* download) {
     return true;
 
   } catch (torrent::local_error& e) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not open download: %s", e.what());
+    lt_log_print(torrent::LOG_TORRENT_EVENTS, "download_list : could not open download : %s", e.what());
     return false;
   }
 }
@@ -237,7 +242,7 @@ void
 DownloadList::open_throw(Download* download) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Opening download.");
+  lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, download->info()->hash(), "download_list : opening download");
 
   if (download->download()->info()->is_open())
     return;
@@ -248,6 +253,7 @@ DownloadList::open_throw(Download* download) {
     openFlags |= torrent::Download::open_enable_fallocate;
 
   download->download()->open(openFlags);
+
   DL_TRIGGER_EVENT(download, "event.download.opened");
 }
 
@@ -257,7 +263,7 @@ DownloadList::close(Download* download) {
     close_throw(download);
 
   } catch (torrent::local_error& e) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not close download: %s", e.what());
+    lt_log_print(torrent::LOG_TORRENT_EVENTS, "download_list : could not close download : %s", e.what());
   }
 }
 
@@ -265,7 +271,7 @@ DownloadList::close(Download* download) {
 // need the files closed and will keep using the download.
 void
 DownloadList::close_files(Download* download) {
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Closing download files.");
+  lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, download->info()->hash(), "download_list : closing download files");
 
   if (download->download()->info()->is_active()) {
     download->download()->stop(torrent::Download::stop_skip_tracker);
@@ -280,7 +286,7 @@ DownloadList::close_files(Download* download) {
 
 void
 DownloadList::close_directly(Download* download) {
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Closing download directly.");
+  lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, download->info()->hash(), "download_list : closing download directly");
 
   auto lifetime   = download->lifetime();
   bool was_active = download->download()->info()->is_active();
@@ -327,7 +333,8 @@ DownloadList::update_paused_state(Download* download) {
 
 void
 DownloadList::close_quick(Download* download) {
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Closing download quickly.");
+  lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, download->info()->hash(), "download_list : closing download quickly.");
+
   close(download);
 
   // Make sure we cancel any tracker requests. This should rather be
@@ -341,7 +348,7 @@ void
 DownloadList::close_throw(Download* download) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Closing download with throw.");
+  LT_LOG_DOWNLOAD_DEBUG("closing download with throw", 0);
 
   // When pause gets called it will clear the initial hash check state
   // and set hash failed. This should ensure hashing doesn't restart
@@ -383,7 +390,7 @@ void
 DownloadList::resume(Download* download, int flags) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Resuming download: flags:%0x.", flags);
+  LT_LOG_DOWNLOAD_DEBUG("resuming download : flags:%0x.", flags);
 
   try {
 
@@ -472,7 +479,7 @@ DownloadList::resume(Download* download, int flags) {
     DL_TRIGGER_EVENT(download, "event.download.resumed");
 
   } catch (torrent::local_error& e) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not resume download: %s", e.what());
+    LT_LOG_DOWNLOAD_EVENTS("could not resume download : %s", e.what());
   }
 }
 
@@ -480,7 +487,7 @@ void
 DownloadList::pause(Download* download, int flags) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Pausing download: flags:%0x.", flags);
+  LT_LOG_DOWNLOAD_DEBUG("pausing download : flags:%0x.", flags);
 
   auto lifetime = download->lifetime();
 
@@ -523,7 +530,7 @@ DownloadList::pause(Download* download, int flags) {
     //control->core()->download_store()->save(download);
 
   } catch (torrent::local_error& e) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not pause download: %s", e.what());
+    LT_LOG_DOWNLOAD_EVENTS("could not pause download : %s", e.what());
   }
 }
 
@@ -531,7 +538,7 @@ void
 DownloadList::check_hash(Download* download) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Checking hash.");
+  LT_LOG_DOWNLOAD_DEBUG("checking hash", 0);
 
   try {
     if (rpc::call_command_value("d.hashing", rpc::make_target(download)) != Download::variable_hashing_stopped)
@@ -540,7 +547,7 @@ DownloadList::check_hash(Download* download) {
     hash_queue(download, Download::variable_hashing_rehash);
 
   } catch (torrent::local_error& e) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not check hash: %s", e.what());
+    LT_LOG_DOWNLOAD_EVENTS("could not check hash : %s", e.what());
   }
 }
 
@@ -548,7 +555,7 @@ void
 DownloadList::hash_done(Download* download) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Hash done.");
+  LT_LOG_DOWNLOAD_DEBUG("hash done", 0);
 
   if (download->is_hash_checking() || download->is_active())
     throw torrent::internal_error("DownloadList::hash_done(...) download in invalid state.");
@@ -613,7 +620,8 @@ DownloadList::hash_done(Download* download) {
       confirm_finished(download);
     } else {
       download->set_message("Hash check on download completion found bad chunks.");
-      lt_log_print(torrent::LOG_TORRENT_ERROR, "Hash check on download completion found bad chunks.");
+      LT_LOG_DOWNLOAD_EVENTS("hash check on download completion found bad chunks", 0);
+
       DL_TRIGGER_EVENT(download, "event.download.hash_final_failed");
     }
 
@@ -634,7 +642,7 @@ void
 DownloadList::hash_queue(Download* download, int type) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Hash queue.");
+  LT_LOG_DOWNLOAD_DEBUG("hash queue : type:%d", type);
 
   if (rpc::call_command_value("d.hashing", rpc::make_target(download)) != Download::variable_hashing_stopped)
     throw torrent::internal_error("DownloadList::hash_queue(...) hashing already queued.");
@@ -678,7 +686,7 @@ void
 DownloadList::received_finished(Download* download) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Received finished.");
+  LT_LOG_DOWNLOAD_DEBUG("received finished", 0);
 
   if (rpc::call_command_value("pieces.hash.on_completion"))
     // Set some 'checking_finished_thingie' variable to make hash_done
@@ -693,7 +701,7 @@ void
 DownloadList::confirm_finished(Download* download) {
   check_contains(download);
 
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Confirming finished.");
+  LT_LOG_DOWNLOAD_DEBUG("confirming finished", 0);
 
   if (download->download()->info()->is_meta_download())
     return process_meta_download(download);
@@ -768,7 +776,7 @@ DownloadList::confirm_finished(Download* download) {
 
 void
 DownloadList::process_meta_download(Download* download) {
-  lt_log_print_info(torrent::LOG_TORRENT_INFO, download->info(), "download_list", "Processing meta download.");
+  LT_LOG_DOWNLOAD_DEBUG("processing meta download", 0);
 
   rpc::call_command("d.stop", torrent::Object(), rpc::make_target(download));
   rpc::call_command("d.close", torrent::Object(), rpc::make_target(download));
@@ -778,7 +786,7 @@ DownloadList::process_meta_download(Download* download) {
   std::fstream file(metafile.c_str(), std::ios::in | std::ios::binary);
 
   if (!file.is_open()) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not read download metadata.");
+    LT_LOG_DOWNLOAD_EVENTS("could not read download metadata : %s", metafile.c_str());
     return;
   }
 
@@ -786,7 +794,7 @@ DownloadList::process_meta_download(Download* download) {
   file >> bencode->insert_key("info", torrent::Object());
 
   if (file.fail()) {
-    lt_log_print(torrent::LOG_TORRENT_ERROR, "Could not create download, the input is not a valid torrent.");
+    LT_LOG_DOWNLOAD_EVENTS("could not create download, the input is not a valid torrent : %s", metafile.c_str());
     return;
   }
 
@@ -794,8 +802,10 @@ DownloadList::process_meta_download(Download* download) {
 
   // Steal the keys we still need. The old download has no use for them.
   bencode->insert_key("rtorrent_meta_download", torrent::Object()).swap(download->bencode()->get_key("rtorrent_meta_download"));
+
   if (download->bencode()->has_key("announce"))
     bencode->insert_key("announce", torrent::Object()).swap(download->bencode()->get_key("announce"));
+
   if (download->bencode()->has_key("announce-list"))
     bencode->insert_key("announce-list", torrent::Object()).swap(download->bencode()->get_key("announce-list"));
 

src/core/download_list.h

@@ -1,6 +1,7 @@
 #ifndef RTORRENT_CORE_DOWNLOAD_LIST_H
 #define RTORRENT_CORE_DOWNLOAD_LIST_H
 
+#include <cstdint>
 #include <iosfwd>
 #include <list>
 #include <memory>

src/core/manager.cc

@@ -440,7 +440,8 @@ Manager::receive_hashing_changed() {
       } else {
         (*itr)->set_hash_failed(true);
         (*itr)->set_message("Hashing failed: " + std::string(e.what()));
-        lt_log_print(torrent::LOG_TORRENT_ERROR, "Hashing failed: %s", e.what());
+
+        lt_log_print_hash_only(torrent::LOG_TORRENT_EVENTS, (*itr)->info()->hash(), "hashing failed : %s", e.what());
       }
     }
   }

src/rpc/command.h

@@ -108,7 +108,7 @@ public:
 
     static stack_type* from_data(char* data) { return reinterpret_cast<stack_type*>(data); }
 
-    char buffer[sizeof(torrent::Object) * max_arguments];
+    alignas(optimal_alignment) char buffer[sizeof(torrent::Object) * max_arguments];
   };
 
   command_base() : m_copy_helper(nullptr), m_dest_helper(nullptr) {}

src/rpc/parse_commands.cc

@@ -123,6 +123,39 @@ parse_command(target_type target, const char* first, const char* last) {
   return std::make_pair(commands.call_command(key, args, target), first);
 }
 
+torrent::Object
+parse_command_object(const char* first, const char* last) {
+  first = std::find_if(first, last, [&](char c) { return !command_map_is_space(c); });
+
+  if (first == last || *first == '#')
+    return torrent::Object();
+
+  char key[128];
+
+  first = parse_command_name(first, last, key, key + 128);
+  first = std::find_if(first, last, [&](char c) { return !command_map_is_space(c); });
+
+  if (first == last || *first != '=')
+    throw torrent::input_error("Could not find '=' in command '" + std::string(key) + "'.");
+
+  torrent::Object result = torrent::Object::create_dict_key();
+
+  result.as_dict_key() = key;
+
+  first = parse_whole_list(first + 1, last, &result.as_dict_obj(), &parse_is_delim_command);
+
+  // Find the last character that is part of this command, skipping
+  // the whitespace at the end.
+  first = std::find_if(first, last, [&](char c) { return !command_map_is_space(c); });
+
+  // This helper accepts exactly one command and cannot return where a next
+  // command begins, so reject every non-whitespace suffix, including ';'.
+  if (first != last && *first != '\0')
+    throw torrent::input_error("Junk at end of input.");
+
+  return result;
+}
+
 torrent::Object
 parse_command_multiple(target_type target, const char* first, const char* last) {
   parse_command_type result;

src/rpc/parse_commands.h

@@ -37,6 +37,9 @@
 
 #include <string>
 #include <cstring>
+#include <functional>
+#include <utility>
+#include <vector>
 
 #include "xmlrpc.h"
 #include "rpc_manager.h"
@@ -67,6 +70,34 @@ parse_command_single(target_type target, const std::string& cmd) {
   return parse_command(target, cmd.c_str(), cmd.c_str() + cmd.size()).first;
 }
 
+// Parse one RPC command without executing it. Repeated evaluations can use
+// call_object on the result, which handles per-target argument expansion.
+torrent::Object        parse_command_object(const char* first, const char* last);
+
+inline torrent::Object parse_command_object(const std::string& cmd) {
+  return parse_command_object(cmd.c_str(), cmd.c_str() + cmd.size());
+}
+
+// Prepare a multicall's commands once, on the first target that uses them. This
+// keeps empty target lists from parsing commands that would never be evaluated.
+struct preparsed_commands : public std::vector<torrent::Object> {
+  explicit preparsed_commands(std::function<void(preparsed_commands&)> prepare)
+    : m_prepare(std::move(prepare)) {}
+
+  void prepare_if_needed() {
+    if (m_prepare) {
+      // Clear before invoking: the callback may inspect this vector, and a
+      // throwing callback must not be run again against partially added items.
+      auto prepare = std::move(m_prepare);
+      m_prepare = {};
+      prepare(*this);
+    }
+  }
+
+private:
+  std::function<void(preparsed_commands&)> m_prepare;
+};
+
 inline torrent::Object
 parse_command_multiple_std(const std::string& cmd, target_type target = rpc::make_target()) {
   return parse_command_multiple(target, cmd.c_str(), cmd.c_str() + cmd.size());

src/ui/element_download_list.cc

@@ -197,8 +197,9 @@ ElementDownloadList::receive_cycle_throttle() {
     return;
 
   core::Download* download = m_view->focus()->get();
+
   if (download->is_active()) {
-    lt_log_print(torrent::LOG_TORRENT_WARN, "Cannot change throttle on active download.");
+    lt_log_print_hash_only(torrent::LOG_TORRENT_DEBUG, download->info()->hash(), "cannot change throttle on active download");
     return;
   }
 

test/rpc/test_command.cc

@@ -2,7 +2,10 @@
 
 #include "test/rpc/test_command.h"
 
+#include <torrent/exceptions.h>
+
 #include "rpc/command.h"
+#include "rpc/parse_commands.h"
 
 CPPUNIT_TEST_SUITE_REGISTRATION(TestCommand);
 
@@ -83,3 +86,50 @@ TestCommand::test_stack_double() {
   rpc::command_base::pop_stack(&stack_first, last_stack_first);
   CPPUNIT_ASSERT(command_stack_all_empty());
 }
+
+void
+TestCommand::test_preparsed_commands() {
+  unsigned int prepare_count = 0;
+  rpc::preparsed_commands commands([&prepare_count](auto& prepared) {
+    ++prepare_count;
+    // Reentrant access must not invoke the same callback recursively.
+    prepared.prepare_if_needed();
+    prepared.push_back(rpc::parse_command_object("string.length=abc"));
+  });
+
+  CPPUNIT_ASSERT_EQUAL(0u, prepare_count);
+  CPPUNIT_ASSERT(commands.empty());
+
+  commands.prepare_if_needed();
+  CPPUNIT_ASSERT_EQUAL(1u, prepare_count);
+
+  size_t count = 0;
+  for (auto& itr : commands) {
+    CPPUNIT_ASSERT(itr.is_dict_key());
+    ++count;
+  }
+
+  CPPUNIT_ASSERT_EQUAL(size_t(1), count);
+  CPPUNIT_ASSERT_EQUAL(1u, prepare_count);
+
+  for (auto& itr : commands)
+    CPPUNIT_ASSERT(itr.is_dict_key());
+
+  CPPUNIT_ASSERT_EQUAL(1u, prepare_count);
+}
+
+void
+TestCommand::test_parse_command_object() {
+  auto command = rpc::parse_command_object("\tstring.length=abc  ");
+  CPPUNIT_ASSERT(command.is_dict_key());
+  CPPUNIT_ASSERT_EQUAL(std::string("string.length"), command.as_dict_key());
+
+  // This helper has no way to return the next-command pointer, so it must not
+  // silently accept a multipart command separated by ';'.
+  CPPUNIT_ASSERT_THROW(rpc::parse_command_object("string.length=abc;string.length=def"), torrent::input_error);
+
+  // Unlike parse_command (which parses command files), this helper handles one
+  // multicall command and must reject newline boundaries, including CRLF.
+  CPPUNIT_ASSERT_THROW(rpc::parse_command_object("string.length=abc\nstring.length=def"), torrent::input_error);
+  CPPUNIT_ASSERT_THROW(rpc::parse_command_object("string.length=abc\r\nstring.length=def"), torrent::input_error);
+}

test/rpc/test_command.h

@@ -5,10 +5,14 @@ class TestCommand : public test_fixture {
 
   CPPUNIT_TEST(test_stack);
   CPPUNIT_TEST(test_stack_double);
+  CPPUNIT_TEST(test_preparsed_commands);
+  CPPUNIT_TEST(test_parse_command_object);
 
   CPPUNIT_TEST_SUITE_END();
 
 public:
   void test_stack();
   void test_stack_double();
+  void test_preparsed_commands();
+  void test_parse_command_object();
 };