implemented asynchronous close and rename of files

src/OutputFileHandler.cc

 #include "OutputFileHandler.h"
 #include "log.h"
+#include "tools.h"
 #include <iomanip>
 
+const std::string OutputFileHandler::working_dir_ = "in_progress";
+const std::string OutputFileHandler::journal_file_ = "index.journal";
+
+tbb::concurrent_bounded_queue<std::pair<std::string, FILE *>>
+    OutputFileHandler::files_to_close_ =
+        tbb::concurrent_bounded_queue<std::pair<std::string, FILE *>>();
+bool OutputFileHandler::file_handler_running_ = false;
+
+void OutputFileHandler::enqueue_current_file_for_close_and_move_maybe() {
+  if (current_file_ != 0)
+    files_to_close_.push(
+        std::pair<std::string, FILE *>(current_filename_, current_file_));
+}
+
+FILE *OutputFileHandler::getFile(uint32_t run, uint32_t index) {
+  if (current_run_number_ != run || current_index_ != index) {
+    enqueue_current_file_for_close_and_move_maybe();
+    current_run_number_ = run;
+    current_index_ = index;
+    open_new_file();
+  }
+  return current_file_;
+}
+
 void OutputFileHandler::create_output_directory_maybe(
     std::string &output_directory) {
   struct stat sb;
@@ -26,29 +51,47 @@ void OutputFileHandler::create_output_directory_maybe(
   LOG(TRACE) << "Created output directory: " << output_directory << "'.";
 }
 
-void OutputFileHandler::open_file(uint32_t index, uint32_t run) {
+void OutputFileHandler::open_new_file() {
   // Create a new file
-  create_output_directory_maybe(working_files_basepath_);
-  std::string filename = working_files_base_path_ + "/" +
-                         format_filename(control.run_number, index);
-  LOG(TRACE) << "opening file with index " << index;
-  current_file_ = fopen( filename.c_str(), "wbx" ));
+  create_output_directory_maybe(working_files_base_path_);
+  current_filename_ = format_filename(current_run_number_, current_index_);
+  std::string full_filename =
+      working_files_base_path_ + "/" + current_filename_;
+  LOG(TRACE) << "opening file with index " << current_index_;
+  current_file_ = fopen(full_filename.c_str(), "wbx");
   if (current_file_ == NULL) {
-    std::string err = tools::strerror("ERROR when creating file '" +
-                                      current_filename_a + "'");
+    std::string err =
+        tools::strerror("ERROR when creating file '" + current_filename_ + "'");
     LOG(ERROR) << err;
     throw std::runtime_error(err);
   }
-  current_index_ = index;
 }
 
-/*
- * Create a properly formatted file name
- */
+// Create a properly formatted file name
+
 std::string OutputFileHandler::format_filename(uint32_t run_number,
                                                uint32_t index) {
   std::ostringstream ofilename;
-  ofilename << filename_prefix_ << "_" << std::setfill(0) << std::setw(6)
+  ofilename << filename_prefix_ << "_" << std::setfill('0') << std::setw(6)
             << run_number << "_" << index << ".dat";
   return ofilename.str();
 }
+
+void OutputFileHandler::close_and_rename::operator()() const {
+  std::pair<std::string, FILE *> n;
+  while (file_handler_running_ || (files_to_close_.size() > 0)) {
+    //	std::cout << std::this_thread::get_id() << " try pop" <<
+    // files_to_close_.size() << std::endl;
+    files_to_close_.pop(n);
+    if (fclose(n.second) != 0) {
+      LOG(ERROR) << tools::strerror("File close failed");
+    }
+    std::string from = base_path_ + "/" + working_dir_ + "/" + n.first;
+    std::string to = base_path_ + "/" + n.first;
+    if (rename(from.c_str(), to.c_str()) != 0) {
+      LOG(ERROR) << tools::strerror("File rename failed");
+    }
+    //	std::cout << std::this_thread::get_id() << " popped " << n.first << "
+    // size now " << files_to_close_.size() << std::endl;
+  }
+}