Make abseil logging sink thread-safe

src/main/main.cc

@@ -40,6 +40,7 @@
 #include <fstream>                                     // for ofstream
 #include <iostream>                                    // for operator<<
 #include <memory>                                      // for unique_ptr
+#include <mutex>                                       // for lock_guard, mutex
 #include <ostream>                                     // for std::flush
 #include <string>                                      // for string
 
@@ -81,10 +82,12 @@ public:
     }
     void Send(const absl::LogEntry& entry) override
     {
+        std::lock_guard<std::mutex> lock(logfile_mutex);
         logfile << entry.text_message_with_prefix_and_newline() << std::flush;
     }
 
 private:
+    std::mutex logfile_mutex;
     std::ofstream logfile;
     std::string filename;
 };

tests/single_test_main.cc

@@ -24,6 +24,7 @@
 #include <fstream>
 #include <iostream>
 #include <memory>
+#include <mutex>
 #include <ostream>
 #include <string>
 
@@ -61,10 +62,12 @@ public:
     }
     void Send(const absl::LogEntry& entry) override
     {
+        std::lock_guard<std::mutex> lock(logfile_mutex);
         logfile << entry.text_message_with_prefix_and_newline() << std::flush;
     }
 
 private:
+    std::mutex logfile_mutex;
     std::ofstream logfile;
 };
 

tests/system-tests/position_test.cc

@@ -47,6 +47,7 @@
 #include <fstream>
 #include <iomanip>
 #include <memory>
+#include <mutex>
 #include <numeric>
 #include <ostream>
 #include <string>
@@ -89,10 +90,12 @@ public:
     }
     void Send(const absl::LogEntry& entry) override
     {
+        std::lock_guard<std::mutex> lock(logfile_mutex);
         logfile << entry.text_message_with_prefix_and_newline() << std::flush;
     }
 
 private:
+    std::mutex logfile_mutex;
     std::ofstream logfile;
 };
 #endif

tests/test_main.cc

@@ -22,6 +22,7 @@
 #include <fstream>
 #include <iostream>
 #include <memory>
+#include <mutex>
 #include <ostream>
 #include <string>
 
@@ -63,10 +64,12 @@ public:
     }
     void Send(const absl::LogEntry& entry) override
     {
+        std::lock_guard<std::mutex> lock(logfile_mutex);
         logfile << entry.text_message_with_prefix_and_newline() << std::flush;
     }
 
 private:
+    std::mutex logfile_mutex;
     std::ofstream logfile;
     std::string filename;
 };

utils/front-end-cal/main.cc

@@ -63,6 +63,7 @@
 #include <iostream>
 #include <map>
 #include <memory>
+#include <mutex>
 #include <stdexcept>  // for logic_error
 #include <string>
 #include <thread>
@@ -122,10 +123,12 @@ public:
     }
     void Send(const absl::LogEntry& entry) override
     {
+        std::lock_guard<std::mutex> lock(logfile_mutex);
         logfile << entry.text_message_with_prefix_and_newline() << std::flush;
     }
 
 private:
+    std::mutex logfile_mutex;
     std::ofstream logfile;
 };