cbmreco: Add flag to write logs to file.

algo/base/Options.cxx

@@ -54,7 +54,9 @@ Options::Options(int argc, char** argv)
       "set log level (debug, info, warning, error, fatal)")
     ("monitor,m", po::value(&fMonitorUri)->value_name("<uri>")->implicit_value("file:cout"),
       "URI specifying monitor output (e.g. file:/tmp/monitor.txt, influx1:login:8086:cbmreco_status). Prints to cout when no argument is given. Monitor is disabled when flag is not set.")
-    ("num-ts,n", po::value(&fNumTimeslices)->default_value(-1)->value_name("<num>"),
+    ("log-file,f", po::value(&fLogFile)->value_name("<file>"),
+      "write log messages to file")
+    ("num-ts,n", po::value<int>(&fNumTimeslices)->default_value(-1)->value_name("<num>"),
       "Stop after <num> timeslices (-1 = all)")
     ("skip-ts,s", po::value(&fSkipTimeslices)->default_value(0)->value_name("<num>"),
       "Skip first <num> timeslices")

algo/base/Options.h

@@ -21,6 +21,7 @@ namespace cbm::algo
     fs::path ParamsDir() const { return fParamsDir; }
     const std::string& InputLocator() const { return fInputLocator; }
     severity_level LogLevel() const { return fLogLevel; }
+    fs::path LogFile() const { return fLogFile; }
     const std::string& Device() const { return fDevice; }
     const std::string& MonitorUri() const { return fMonitorUri; }
     bool CollectKernelTimes() const { return fCollectKernelTimes; }
@@ -31,6 +32,7 @@ namespace cbm::algo
     std::string fParamsDir;  // TODO: can we make this a std::path?
     std::string fInputLocator;
     severity_level fLogLevel;
+    std::string fLogFile;
     std::string fDevice;
     std::string fMonitorUri;
     bool fCollectKernelTimes = false;

reco/app/cbmreco/main.cxx

@@ -19,6 +19,8 @@ int main(int argc, char** argv)
 
   logging::add_console(opts.LogLevel());
 
+  if (!opts.LogFile().empty()) logging::add_file(opts.LogFile().string(), opts.LogLevel());
+
   // XPU
   xpu::settings settings;
   settings.profile = opts.CollectKernelTimes();