[ENH] Customization feature to choose a directory for dumping of log files during runtime

doc/source/reference/idefix.ini.rst

@@ -411,6 +411,9 @@ This section describes the outputs *Idefix* produces. For more details about eac
 +================+=========================+==================================================================================================+
 | log            | integer                 | | Time interval between log outputs, in code steps (default 100).                                |
 +----------------+-------------------------+--------------------------------------------------------------------------------------------------+
+| log_dir        | string                  | | directory for log file outputs. Default to "./"                                                |
+|                |                         | | The directory is automatically created if it does not exist.                                   |
++----------------+-------------------------+--------------------------------------------------------------------------------------------------+
 | dmp            | float, float+char       | | 1st parameter: Code time interval between dump outputs, in code units.                         |
 |                |                         | | If negative, the first parameter is ignored.                                                   |
 |                |                         | | 2nd parameter (optional): Wallclock time interval between two dumps. The ending character      |

src/global.cpp

@@ -8,6 +8,16 @@
 #include <iostream>
 #include <string>
 #include <sstream>
+#if __has_include(<filesystem>)
+  #include <filesystem> // NOLINT [build/c++17]
+  namespace fs = std::filesystem;
+#elif __has_include(<experimental/filesystem>)
+  #include <experimental/filesystem>
+  namespace fs = std::experimental::filesystem;
+#else
+  #error "Missing the <filesystem> header."
+#endif
+
 #include "idefix.hpp"
 #include "global.hpp"
 #include "profiler.hpp"
@@ -105,13 +115,31 @@ void IdefixOutStream::init(int rank) {
 
 
 // disable the log file
-void IdefixOutStream::enableLogFile() {
+void IdefixOutStream::enableLogFile(std::string logFileDir) {
   std::stringstream sslogFileName;
-  sslogFileName << "idefix." << idfx::prank << ".log";
-
+  sslogFileName << logFileDir << "/"  << "idefix." << idfx::prank << ".log";
   std::string logFileName(sslogFileName.str());
-  this->my_fstream.open(logFileName.c_str());
 
+  if(idfx::prank==0) {
+    if(!fs::is_directory(logFileDir)) {
+      try {
+        if(!fs::create_directories(logFileDir)) {
+          std::stringstream msg;
+          msg << "Cannot create directory " << logFileDir << std::endl;
+          IDEFIX_ERROR(msg);
+        }
+      } catch(std::exception &e) {
+        std::stringstream msg;
+        msg << "Cannot create directory " << logFileDir << std::endl;
+        msg << e.what();
+        IDEFIX_ERROR(msg);
+      }
+    }
+  }
+#ifdef WITH_MPI
+  MPI_Barrier(MPI_COMM_WORLD);
+#endif
+  this->my_fstream.open(logFileName.c_str());
   this->logFileEnabled = true;
 }
 

src/global.hpp

@@ -24,6 +24,7 @@ class Units;
 
 extern int prank;                       //< parallel rank
 extern int psize;
+extern std::string logFileDir;       //< logfileDir
 extern IdefixOutStream cout;              //< custom cout for idefix
 extern IdefixErrStream cerr;              //< custom cerr for idefix
 extern Profiler prof;                   //< profiler (for memory & performance usage)
@@ -66,7 +67,7 @@ void DumpArray(std::string filename, ArrayType array) {
 class idfx::IdefixOutStream {
  public:
   void init(int);
-  void enableLogFile();
+  void enableLogFile(std::string logFileDir);
   // for regular output of variables and stuff
   template<typename T> IdefixOutStream& operator<<(const T& something) {
     if(toscreen) std::cout << something;

src/input.cpp

@@ -44,6 +44,8 @@ Input::Input(int argc, char* argv[] ) {
   bool haveBlock = false;
   std::stringstream msg;
   int nParameters = 0;    // # of parameters in current block
+  // Log files are enabled by default
+  this->enableLogs = true;
 
   // Tell the system we want to catch the SIGUSR2 signals
   signal(SIGUSR2, signalHandler);
@@ -109,12 +111,19 @@ Input::Input(int argc, char* argv[] ) {
     }
   }
   file.close();
+
+  if(this->enableLogs) {
+    std::string logFileDir{"./"};
+    if(CheckEntry("Output","log_dir")>=0) {
+      logFileDir = Get<std::string>("Output", "log_dir", 0);
+    }
+    idfx::cout.enableLogFile(logFileDir);
+  }
 }
 
 // This routine parse command line options
 void Input::ParseCommandLine(int argc, char **argv) {
   std::stringstream msg;
-  bool enableLogs = true;
   for(int i = 1 ; i < argc ; i++) {
     // MPI decomposition argument
     if(std::string(argv[i]) == "-dec") {
@@ -172,9 +181,9 @@ void Input::ParseCommandLine(int argc, char **argv) {
       this->forceInitRequested = true;
     } else if(std::string(argv[i]) == "-nowrite") {
       this->forceNoWrite = true;
-      enableLogs = false;
+      this->enableLogs = false;
     } else if(std::string(argv[i]) == "-nolog") {
-      enableLogs = false;
+      this->enableLogs = false;
     } else if(std::string(argv[i]) == "-profile") {
       idfx::prof.EnablePerformanceProfiling();
     } else if(std::string(argv[i]) == "-Werror") {
@@ -191,9 +200,6 @@ void Input::ParseCommandLine(int argc, char **argv) {
       IDEFIX_ERROR(msg);
     }
   }
-  if(enableLogs) {
-    idfx::cout.enableLogFile();
-  }
 }
 
 

src/input.hpp

@@ -25,6 +25,9 @@ class Input {
   Input (int, char ** );
   void ShowConfig();
 
+  // flag if logging is to be done
+  bool enableLogs;
+
   // Accessor to input parameters
   // the parameters are always: BlockName, EntryName, ParameterNumber (starting from 0)
   // These specialised functions are deprecated. Use the template Get<T> function.