Small code enhancements according to clang-tidy. [#CLICKHOUSE-2931]

dbms/src/Common/PoolWithFailoverBase.h

@@ -350,7 +350,7 @@ PoolWithFailoverBase<TNestedPool>::updatePoolStates()
         for (auto & state : shared_pool_states)
             state.randomize();
 
-        time_t current_time = time(0);
+        time_t current_time = time(nullptr);
 
         if (last_error_decrease_time)
         {

dbms/src/Common/ZooKeeper/tests/zkutil_expiration_test.cpp

@@ -27,7 +27,7 @@ int main(int argc, char ** argv)
 
         std::cerr << "Please run `./nozk.sh && sleep 40s && ./yeszk.sh`" << std::endl;
 
-        time_t time0 = time(0);
+        time_t time0 = time(nullptr);
 
         while (true)
         {

dbms/src/DataStreams/IProfilingBlockInputStream.cpp

@@ -203,7 +203,7 @@ void IProfilingBlockInputStream::checkQuota(Block & block)
 
         case LIMITS_CURRENT:
         {
-            time_t current_time = time(0);
+            time_t current_time = time(nullptr);
             double total_elapsed = info.total_stopwatch.elapsedSeconds();
 
             quota->checkAndAddResultRowsBytes(current_time, block.rows(), block.bytes());

dbms/src/Interpreters/executeQuery.cpp

@@ -128,7 +128,7 @@ static std::tuple<ASTPtr, BlockIO> executeQueryImpl(
     QueryProcessingStage::Enum stage)
 {
     ProfileEvents::increment(ProfileEvents::Query);
-    time_t current_time = time(0);
+    time_t current_time = time(nullptr);
 
     const Settings & settings = context.getSettingsRef();
 
@@ -253,7 +253,7 @@ static std::tuple<ASTPtr, BlockIO> executeQueryImpl(
 
                 elem.type = QueryLogElement::QUERY_FINISH;
 
-                elem.event_time = time(0);
+                elem.event_time = time(nullptr);
                 elem.query_duration_ms = elapsed_seconds * 1000;
 
                 elem.read_rows = process_list_elem->progress_in.rows;
@@ -305,7 +305,7 @@ static std::tuple<ASTPtr, BlockIO> executeQueryImpl(
 
                 elem.type = QueryLogElement::EXCEPTION_WHILE_PROCESSING;
 
-                elem.event_time = time(0);
+                elem.event_time = time(nullptr);
                 elem.query_duration_ms = 1000 * (elem.event_time - elem.query_start_time);
                 elem.exception = getCurrentExceptionMessage(false);
 

dbms/src/Server/Client.cpp

@@ -249,7 +249,7 @@ private:
     /// Should we celebrate a bit?
     bool isNewYearMode()
     {
-        time_t current_time = time(0);
+        time_t current_time = time(nullptr);
 
         /// It's bad to be intrusive.
         if (current_time % 3 != 0)

dbms/src/Storages/MergeTree/DataPartsExchange.cpp

@@ -265,7 +265,7 @@ MergeTreeData::MutableDataPartPtr Fetcher::fetchPartImpl(
     assertEOF(in);
 
     ActiveDataPartSet::parsePartName(part_name, *new_data_part);
-    new_data_part->modification_time = time(0);
+    new_data_part->modification_time = time(nullptr);
     new_data_part->loadColumns(true);
     new_data_part->loadChecksums(true);
     new_data_part->loadIndex();

dbms/src/Storages/MergeTree/MergeTreeData.cpp

@@ -483,7 +483,7 @@ void MergeTreeData::clearOldTemporaryDirectories(ssize_t custom_directories_life
     if (!lock.try_lock())
         return;
 
-    time_t current_time = time(0);
+    time_t current_time = time(nullptr);
     ssize_t deadline = (custom_directories_lifetime_seconds >= 0)
         ? current_time - custom_directories_lifetime_seconds
         : current_time - settings.temporary_directories_lifetime;
@@ -522,12 +522,12 @@ MergeTreeData::DataPartsVector MergeTreeData::grabOldParts()
     if (!lock.try_lock())
         return res;
 
-    time_t now = time(0);
+    time_t now = time(nullptr);
 
     {
-        std::lock_guard<std::mutex> lock(all_data_parts_mutex);
+        std::lock_guard<std::mutex> lock_all_parts(all_data_parts_mutex);
 
-        for (DataParts::iterator it = all_data_parts.begin(); it != all_data_parts.end();)
+        for (auto it = all_data_parts.begin(); it != all_data_parts.end();)
         {
             if (it->unique() && /// After this ref_count cannot increase.
                 (*it)->remove_time < now &&
@@ -1047,7 +1047,7 @@ MergeTreeData::AlterDataPartTransactionPtr MergeTreeData::alterDataPart(
     DataPart::Checksums new_checksums = part->checksums;
     for (auto it : transaction->rename_map)
     {
-        if (it.second == "")
+        if (it.second.empty())
             new_checksums.files.erase(it.first);
         else
             new_checksums.files[it.second] = add_checksums.files[it.first];
@@ -1110,7 +1110,7 @@ void MergeTreeData::AlterDataPartTransaction::commit()
                 Poco::File{path + it.first}.renameTo(path + it.second);
         }
 
-        DataPart & mutable_part = const_cast<DataPart &>(*data_part);
+        auto & mutable_part = const_cast<DataPart &>(*data_part);
         mutable_part.checksums = new_checksums;
         mutable_part.columns = new_columns;
 
@@ -1231,7 +1231,7 @@ MergeTreeData::DataPartsVector MergeTreeData::renameTempPartAndReplace(
 
         /// Parts contained in the part are consecutive in data_parts, intersecting the insertion place
         /// for the part itself.
-        DataParts::iterator it = data_parts.lower_bound(part);
+        auto it = data_parts.lower_bound(part);
         /// Go to the left.
         while (it != data_parts.begin())
         {
@@ -1244,7 +1244,7 @@ MergeTreeData::DataPartsVector MergeTreeData::renameTempPartAndReplace(
                 break;
             }
             replaced.push_back(*it);
-            (*it)->remove_time = time(0);
+            (*it)->remove_time = time(nullptr);
             removePartContributionToColumnSizes(*it);
             data_parts.erase(it++); /// Yes, ++, not --.
         }
@@ -1259,7 +1259,7 @@ MergeTreeData::DataPartsVector MergeTreeData::renameTempPartAndReplace(
                 break;
             }
             replaced.push_back(*it);
-            (*it)->remove_time = time(0);
+            (*it)->remove_time = time(nullptr);
             removePartContributionToColumnSizes(*it);
             data_parts.erase(it++);
         }
@@ -1267,7 +1267,7 @@ MergeTreeData::DataPartsVector MergeTreeData::renameTempPartAndReplace(
         if (obsolete)
         {
             LOG_WARNING(log, "Obsolete part " << part->name << " added");
-            part->remove_time = time(0);
+            part->remove_time = time(nullptr);
         }
         else
         {
@@ -1488,7 +1488,7 @@ MergeTreeData::DataPartPtr MergeTreeData::getActiveContainingPart(const String &
     std::lock_guard<std::mutex> lock(data_parts_mutex);
 
     /// The part can be covered only by the previous or the next one in data_parts.
-    DataParts::iterator it = data_parts.lower_bound(tmp_part);
+    auto it = data_parts.lower_bound(tmp_part);
 
     if (it != data_parts.end())
     {
@@ -1514,7 +1514,7 @@ MergeTreeData::DataPartPtr MergeTreeData::getPartIfExists(const String & part_na
     ActiveDataPartSet::parsePartName(part_name, *tmp_part);
 
     std::lock_guard<std::mutex> lock(all_data_parts_mutex);
-    DataParts::iterator it = all_data_parts.lower_bound(tmp_part);
+    auto it = all_data_parts.lower_bound(tmp_part);
     if (it != all_data_parts.end() && (*it)->name == part_name)
         return *it;
 
@@ -1527,8 +1527,8 @@ MergeTreeData::DataPartPtr MergeTreeData::getShardedPartIfExists(const String &
 
     if (part_from_shard->name == part_name)
         return part_from_shard;
-    else
-        return nullptr;
+
+    return nullptr;
 }
 
 MergeTreeData::MutableDataPartPtr MergeTreeData::loadPartAndFixMetadata(const String & relative_path)

dbms/src/Storages/MergeTree/MergeTreeDataMerger.cpp

@@ -262,7 +262,7 @@ bool MergeTreeDataMerger::selectAllPartsToMergeWithinPartition(
     /// Enough disk space to cover the new merge with a margin.
     if (available_disk_space <= sum_bytes * DISK_USAGE_COEFFICIENT_TO_SELECT)
     {
-        time_t now = time(0);
+        time_t now = time(nullptr);
         if (now - disk_space_warning_time > 3600)
         {
             disk_space_warning_time = now;
@@ -758,7 +758,7 @@ MergeTreeData::MutableDataPartPtr MergeTreeDataMerger::mergePartsToTemporaryPart
         throw Exception("Empty part after merge", ErrorCodes::LOGICAL_ERROR);
 
     new_data_part->size = to.marksCount();
-    new_data_part->modification_time = time(0);
+    new_data_part->modification_time = time(nullptr);
     new_data_part->size_in_bytes = MergeTreeData::DataPart::calcTotalSize(new_part_tmp_path);
     new_data_part->is_sharded = false;
 
@@ -1080,7 +1080,7 @@ MergeTreeData::PerShardDataParts MergeTreeDataMerger::reshardPartition(
         data_part->checksums = output_stream->writeSuffixAndGetChecksums();
         data_part->index.swap(output_stream->getIndex());
         data_part->size = output_stream->marksCount();
-        data_part->modification_time = time(0);
+        data_part->modification_time = time(nullptr);
         data_part->size_in_bytes = MergeTreeData::DataPart::calcTotalSize(output_stream->getPartPath());
         data_part->is_sharded = true;
         data_part->shard_no = shard_no;

dbms/src/Storages/MergeTree/MergeTreeDataWriter.cpp

@@ -163,7 +163,7 @@ MergeTreeData::MutableDataPartPtr MergeTreeDataWriter::writeTempPart(BlockWithDa
     new_data_part->right = temp_index;
     new_data_part->level = 0;
     new_data_part->size = part_size;
-    new_data_part->modification_time = time(0);
+    new_data_part->modification_time = time(nullptr);
     new_data_part->month = min_month;
     new_data_part->columns = columns;
     new_data_part->checksums = checksums;

dbms/src/Storages/MergeTree/ReplicatedMergeTreeBlockOutputStream.cpp

@@ -182,7 +182,7 @@ void ReplicatedMergeTreeBlockOutputStream::commitPart(zkutil::ZooKeeperPtr & zoo
 
     StorageReplicatedMergeTree::LogEntry log_entry;
     log_entry.type = StorageReplicatedMergeTree::LogEntry::GET_PART;
-    log_entry.create_time = time(0);
+    log_entry.create_time = time(nullptr);
     log_entry.source_replica = storage.replica_name;
     log_entry.new_part_name = part_name;
     log_entry.quorum = quorum;

dbms/src/Storages/MergeTree/ReplicatedMergeTreePartCheckThread.cpp

@@ -305,7 +305,7 @@ void ReplicatedMergeTreePartCheckThread::run()
     {
         try
         {
-            time_t current_time = time(0);
+            time_t current_time = time(nullptr);
 
             /// Take part from the queue for verification.
             PartsToCheckQueue::iterator selected = parts_queue.end();    /// end from std::list is not get invalidated

dbms/src/Storages/MergeTree/ReplicatedMergeTreeQueue.cpp

@@ -341,7 +341,7 @@ bool ReplicatedMergeTreeQueue::pullLogsToQueue(zkutil::ZooKeeperPtr zookeeper, z
                     insertUnlocked(copied_entries[i]);
                 }
 
-                last_queue_update = time(0);
+                last_queue_update = time(nullptr);
             }
             catch (...)
             {
@@ -644,7 +644,7 @@ ReplicatedMergeTreeQueue::CurrentlyExecuting::CurrentlyExecuting(ReplicatedMerge
 {
     entry->currently_executing = true;
     ++entry->num_tries;
-    entry->last_attempt_time = time(0);
+    entry->last_attempt_time = time(nullptr);
 
     if (!queue.future_parts.insert(entry->new_part_name).second)
         throw Exception("Tagging already tagged future part " + entry->new_part_name + ". This is a bug.", ErrorCodes::LOGICAL_ERROR);
@@ -708,7 +708,7 @@ ReplicatedMergeTreeQueue::SelectedEntry ReplicatedMergeTreeQueue::selectEntryToP
         else
         {
             ++(*it)->num_postponed;
-            (*it)->last_postpone_time = time(0);
+            (*it)->last_postpone_time = time(nullptr);
         }
     }
 

dbms/src/Storages/MergeTree/ReplicatedMergeTreeRestartingThread.cpp

@@ -112,7 +112,7 @@ void ReplicatedMergeTreeRestartingThread::run()
                 first_time = false;
             }
 
-            time_t current_time = time(0);
+            time_t current_time = time(nullptr);
             if (current_time >= prev_time_of_check_delay + static_cast<time_t>(storage.data.settings.check_delay_period))
             {
                 /// Find out lag of replicas.

dbms/src/Storages/MergeTree/ShardedPartitionUploader.cpp

@@ -105,7 +105,7 @@ void Service::processQuery(const Poco::Net::HTMLForm & params, ReadBuffer & body
     assertEOF(body);
 
     ActiveDataPartSet::parsePartName(part_name, *data_part);
-    data_part->modification_time = time(0);
+    data_part->modification_time = time(nullptr);
     data_part->loadColumns(true);
     data_part->loadChecksums(true);
     data_part->loadIndex();

dbms/src/Storages/StorageBuffer.cpp

@@ -296,7 +296,7 @@ private:
 
     void insertIntoBuffer(const Block & block, StorageBuffer::Buffer & buffer, std::unique_lock<std::mutex> && lock)
     {
-        time_t current_time = time(0);
+        time_t current_time = time(nullptr);
 
         /// Sort the columns in the block. This is necessary to make it easier to concatenate the blocks later.
         Block sorted_block = block.sortColumns();
@@ -434,7 +434,7 @@ void StorageBuffer::flushAllBuffers(const bool check_thresholds)
 void StorageBuffer::flushBuffer(Buffer & buffer, bool check_thresholds)
 {
     Block block_to_write;
-    time_t current_time = time(0);
+    time_t current_time = time(nullptr);
 
     size_t rows = 0;
     size_t bytes = 0;

dbms/src/Storages/StorageMergeTree.cpp

@@ -343,7 +343,7 @@ bool StorageMergeTree::merge(
     if (auto part_log = context.getPartLog(database_name, table_name))
     {
         PartLogElement elem;
-        elem.event_time = time(0);
+        elem.event_time = time(nullptr);
 
         elem.merged_from.reserve(merging_tagger->parts.size());
         for (const auto & part : merging_tagger->parts)

dbms/src/Storages/StorageReplicatedMergeTree.cpp

@@ -1120,7 +1120,7 @@ bool StorageReplicatedMergeTree::executeLogEntry(const LogEntry & entry)
                 if (auto part_log = context.getPartLog(database_name, table_name))
                 {
                     PartLogElement elem;
-                    elem.event_time = time(0);
+                    elem.event_time = time(nullptr);
 
                     elem.merged_from.reserve(parts.size());
                     for (const auto & part : parts)
@@ -1843,7 +1843,7 @@ bool StorageReplicatedMergeTree::createLogEntryToMergeParts(
     entry.source_replica = replica_name;
     entry.new_part_name = merged_name;
     entry.deduplicate = deduplicate;
-    entry.create_time = time(0);
+    entry.create_time = time(nullptr);
 
     for (const auto & part : parts)
         entry.parts_to_merge.push_back(part->name);
@@ -2147,7 +2147,7 @@ bool StorageReplicatedMergeTree::fetchPart(const String & part_name, const Strin
         if (auto part_log = context.getPartLog(database_name, table_name))
         {
             PartLogElement elem;
-            elem.event_time = time(0);
+            elem.event_time = time(nullptr);
             elem.event_type = PartLogElement::DOWNLOAD_PART;
             elem.size_in_bytes = part->size_in_bytes;
             elem.duration_ms = stopwatch.elapsed() / 10000000;
@@ -2650,7 +2650,7 @@ void StorageReplicatedMergeTree::clearColumnInPartition(
     entry.type = LogEntry::CLEAR_COLUMN;
     entry.new_part_name = fake_part_name;
     entry.column_name = column_name.safeGet<String>();
-    entry.create_time = time(0);
+    entry.create_time = time(nullptr);
 
     String log_znode_path = getZooKeeper()->create(zookeeper_path + "/log/log-", entry.toString(), zkutil::CreateMode::PersistentSequential);
     entry.znode_name = log_znode_path.substr(log_znode_path.find_last_of('/') + 1);
@@ -2700,7 +2700,7 @@ void StorageReplicatedMergeTree::dropPartition(const ASTPtr & query, const Field
     entry.source_replica = replica_name;
     entry.new_part_name = fake_part_name;
     entry.detach = detach;
-    entry.create_time = time(0);
+    entry.create_time = time(nullptr);
 
     String log_znode_path = getZooKeeper()->create(zookeeper_path + "/log/log-", entry.toString(), zkutil::CreateMode::PersistentSequential);
     entry.znode_name = log_znode_path.substr(log_znode_path.find_last_of('/') + 1);

dbms/src/Storages/StorageTrivialBuffer.cpp

@@ -191,7 +191,7 @@ void StorageTrivialBuffer::addBlock(const Block & block, DeduplicationController
 void StorageTrivialBuffer::flush(bool check_thresholds, bool is_called_from_background)
 {
     Block block_to_write;
-    time_t current_time = time(0);
+    time_t current_time = time(nullptr);
 
     time_t time_passed = 0;
 
@@ -316,7 +316,7 @@ public:
             }
         }
 
-        time_t current_time = time(0);
+        time_t current_time = time(nullptr);
         if (buffer.checkThresholds(current_time, rows, bytes))
         {
             /** We'll try to flush the buffer if thresholds are overdrafted.

libs/libcommon/include/common/logger_useful.h

@@ -17,46 +17,46 @@ using Poco::Logger;
     if ((logger)->trace()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->trace(oss_internal_rare.str());}} while(0)
+    (logger)->trace(oss_internal_rare.str());}} while(false)
 
 #define LOG_DEBUG(logger, message) do { \
     if ((logger)->debug()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->debug(oss_internal_rare.str());}} while(0)
+    (logger)->debug(oss_internal_rare.str());}} while(false)
 
 #define LOG_INFO(logger, message) do { \
     if ((logger)->information()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->information(oss_internal_rare.str());}} while(0)
+    (logger)->information(oss_internal_rare.str());}} while(false)
 
 #define LOG_NOTICE(logger, message) do { \
     if ((logger)->notice()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->notice(oss_internal_rare.str());}} while(0)
+    (logger)->notice(oss_internal_rare.str());}} while(false)
 
 #define LOG_WARNING(logger, message) do { \
     if ((logger)->warning()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->warning(oss_internal_rare.str());}} while(0)
+    (logger)->warning(oss_internal_rare.str());}} while(false)
 
 #define LOG_ERROR(logger, message) do { \
     if ((logger)->error()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->error(oss_internal_rare.str());}} while(0)
+    (logger)->error(oss_internal_rare.str());}} while(false)
 
 #define LOG_CRITICAL(logger, message) do { \
     if ((logger)->critical()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->critical(oss_internal_rare.str());}} while(0)
+    (logger)->critical(oss_internal_rare.str());}} while(false)
 
 #define LOG_FATAL(logger, message) do { \
     if ((logger)->fatal()) {\
     std::stringstream oss_internal_rare;    \
     oss_internal_rare << message; \
-    (logger)->fatal(oss_internal_rare.str());}} while(0)
+    (logger)->fatal(oss_internal_rare.str());}} while(false)