[wpiutil, wpilib] Add FileLogger and integrate with DLM

ntcoreffi/src/main/native/cpp/DataLogManager.cpp

@@ -14,6 +14,7 @@
 #include <fmt/format.h>
 #include <networktables/NetworkTableInstance.h>
 #include <wpi/DataLogBackgroundWriter.h>
+#include <wpi/FileLogger.h>
 #include <wpi/SafeThread.h>
 #include <wpi/StringExtras.h>
 #include <wpi/fs.h>
@@ -191,13 +192,17 @@ struct Thread final : public wpi::SafeThread {
 
   void StartNTLog();
   void StopNTLog();
+  void StartConsoleLog();
+  void StopConsoleLog();
 
   std::string m_logDir;
   bool m_filenameOverride;
   wpi::log::DataLogBackgroundWriter m_log;
   bool m_ntLoggerEnabled = false;
   NT_DataLogger m_ntEntryLogger = 0;
   NT_ConnectionDataLogger m_ntConnLogger = 0;
+  bool m_consoleLoggerEnabled = false;
+  wpi::FileLogger m_consoleLogger;
   wpi::log::StringLogEntry m_messageLog;
 };
 
@@ -452,6 +457,20 @@ void Thread::StopNTLog() {
   }
 }
 
+void Thread::StartConsoleLog() {
+  if (!m_consoleLoggerEnabled) {
+    m_consoleLoggerEnabled = true;
+    m_consoleLogger = {"FRC_UserProgram.log", m_log, "output"};
+  }
+}
+
+void Thread::StopConsoleLog() {
+  if (m_consoleLoggerEnabled) {
+    m_consoleLoggerEnabled = false;
+    m_consoleLogger = {};
+  }
+}
+
 Instance::Instance(std::string_view dir, std::string_view filename,
                    double period) {
   // Delete all previously existing FRC_TBD_*.wpilog files. These only exist
@@ -516,6 +535,16 @@ void DataLogManager::LogNetworkTables(bool enabled) {
   }
 }
 
+void DataLogManager::LogConsoleOutput(bool enabled) {
+  if (auto thr = GetInstance().owner.GetThread()) {
+    if (enabled) {
+      thr->StartConsoleLog();
+    } else if (!enabled) {
+      thr->StopConsoleLog();
+    }
+  }
+}
+
 void DataLogManager::SignalNewDSDataOccur() {
   wpi::SetSignalObject(DriverStation::gNewDataEvent);
 }
@@ -546,6 +575,10 @@ void DLM_LogNetworkTables(int enabled) {
   DataLogManager::LogNetworkTables(enabled);
 }
 
+void DLM_LogConsoleOutput(int enabled) {
+  DataLogManager::LogConsoleOutput(enabled);
+}
+
 void DLM_SignalNewDSDataOccur(void) {
   DataLogManager::SignalNewDSDataOccur();
 }

ntcoreffi/src/main/native/include/DataLogManager.h

@@ -89,6 +89,11 @@ class DataLogManager final {
    */
   static void LogNetworkTables(bool enabled);
 
+  /**
+   * Enable or disable logging of the console output. Defaults to enabled.
+   * @param enabled  true to enable, false to disable
+   */
+  static void LogConsoleOutput(bool enabled);
   /**
    * Signal new DS data is available.
    */
@@ -152,6 +157,13 @@ const char* DLM_GetLogDir(void);
  */
 void DLM_LogNetworkTables(int enabled);
 
+
+  /**
+   * Enable or disable logging of the console output. Defaults to enabled.
+   * @param enabled  true to enable, false to disable
+   */
+void DLM_LogConsoleOutput(int enabled);
+
 /**
  * Signal new DS data is available.
  */

ntcoreffi/src/main/native/symbols.txt

@@ -1,6 +1,7 @@
 DLM_GetLog
 DLM_GetLogDir
 DLM_Log
+DLM_LogConsoleOutput
 DLM_LogNetworkTables
 DLM_SignalNewDSDataOccur
 DLM_Start

wpilibc/src/main/native/cpp/DataLogManager.cpp

@@ -13,6 +13,7 @@
 #include <fmt/chrono.h>
 #include <networktables/NetworkTableInstance.h>
 #include <wpi/DataLog.h>
+#include <wpi/FileLogger.h>
 #include <wpi/DataLogBackgroundWriter.h>
 #include <wpi/SafeThread.h>
 #include <wpi/StringExtras.h>
@@ -37,13 +38,17 @@ struct Thread final : public wpi::SafeThread {
 
   void StartNTLog();
   void StopNTLog();
+  void StartConsoleLog();
+  void StopConsoleLog();
 
   std::string m_logDir;
   bool m_filenameOverride;
   wpi::log::DataLogBackgroundWriter m_log;
   bool m_ntLoggerEnabled = false;
   NT_DataLogger m_ntEntryLogger = 0;
   NT_ConnectionDataLogger m_ntConnLogger = 0;
+  bool m_consoleLoggerEnabled = false;
+  wpi::FileLogger m_consoleLogger;
   wpi::log::StringLogEntry m_messageLog;
 };
 
@@ -109,10 +114,12 @@ Thread::Thread(std::string_view dir, std::string_view filename, double period)
       m_log{dir, MakeLogFilename(filename), period},
       m_messageLog{m_log, "messages"} {
   StartNTLog();
+  StartConsoleLog();
 }
 
 Thread::~Thread() {
   StopNTLog();
+  StopConsoleLog();
 }
 
 void Thread::Main() {
@@ -297,6 +304,20 @@ void Thread::StopNTLog() {
   }
 }
 
+void Thread::StartConsoleLog() {
+  if (!m_consoleLoggerEnabled) {
+    m_consoleLoggerEnabled = true;
+    m_consoleLogger = {"FRC_UserProgram.log", m_log, "output"};
+  }
+}
+
+void Thread::StopConsoleLog() {
+  if (m_consoleLoggerEnabled) {
+    m_consoleLoggerEnabled = false;
+    m_consoleLogger = {};
+  }
+}
+
 Instance::Instance(std::string_view dir, std::string_view filename,
                    double period) {
   // Delete all previously existing FRC_TBD_*.wpilog files. These only exist
@@ -360,3 +381,13 @@ void DataLogManager::LogNetworkTables(bool enabled) {
     }
   }
 }
+
+void DataLogManager::LogConsoleOutput(bool enabled) {
+  if (auto thr = GetInstance().owner.GetThread()) {
+    if (enabled) {
+      thr->StartConsoleLog();
+    } else if (!enabled) {
+      thr->StopConsoleLog();
+    }
+  }
+}

wpilibc/src/main/native/include/frc/DataLogManager.h

@@ -85,6 +85,13 @@ class DataLogManager final {
    * @param enabled true to enable, false to disable
    */
   static void LogNetworkTables(bool enabled);
+
+
+  /**
+   * Enable or disable logging of the console output. Defaults to enabled.
+   * @param enabled  true to enable, false to disable
+   */
+  static void LogConsoleOutput(bool enabled);
 };
 
 }  // namespace frc

wpilibj/src/main/java/edu/wpi/first/wpilibj/DataLogManager.java

@@ -5,6 +5,7 @@
 package edu.wpi.first.wpilibj;
 
 import edu.wpi.first.networktables.NetworkTableInstance;
+import edu.wpi.first.util.FileLogger;
 import edu.wpi.first.util.WPIUtilJNI;
 import edu.wpi.first.util.concurrent.Event;
 import edu.wpi.first.util.datalog.DataLog;
@@ -52,6 +53,8 @@ public final class DataLogManager {
   private static boolean m_ntLoggerEnabled = true;
   private static int m_ntEntryLogger;
   private static int m_ntConnLogger;
+  private static boolean m_consoleLoggerEnabled = true;
+  private static FileLogger m_consoleLogger;
   private static StringLogEntry m_messageLog;
 
   // if less than this much free space, delete log files until there is this much free space
@@ -121,6 +124,10 @@ public static synchronized void start(String dir, String filename, double period
       if (m_ntLoggerEnabled) {
         startNtLog();
       }
+      // Log console output
+      if (m_consoleLoggerEnabled) {
+        startConsoleLog();
+      }
     } else if (m_stopped) {
       m_log.setFilename(makeLogFilename(filename));
       m_log.resume();
@@ -205,6 +212,24 @@ public static synchronized void logNetworkTables(boolean enabled) {
     }
   }
 
+  /**
+   * Enable or disable logging of the console output. Defaults to enabled.
+   * @param enabled  true to enable, false to disable
+   */
+  public static synchronized void logConsoleOutput(boolean enabled) {
+    boolean wasEnabled = m_consoleLoggerEnabled;
+    m_consoleLoggerEnabled = enabled;
+    if (m_log == null) {
+      start();
+      return;
+    }
+    if (enabled && !wasEnabled) {
+      startConsoleLog();
+    } else if (!enabled && wasEnabled) {
+      stopConsoleLog();
+    }
+  }
+
   private static String makeLogDir(String dir) {
     if (!dir.isEmpty()) {
       return dir;
@@ -266,6 +291,14 @@ private static void stopNtLog() {
     NetworkTableInstance.stopConnectionDataLog(m_ntConnLogger);
   }
 
+  private static void startConsoleLog() {
+    m_consoleLogger = new FileLogger("FRC_UserProgram.log", m_log, "console");
+  }
+
+  private static void stopConsoleLog() {
+    m_consoleLogger.close();
+  }
+
   private static void logMain() {
     // based on free disk space, scan for "old" FRC_*.wpilog files and remove
     {

wpiutil/src/main/java/edu/wpi/first/util/FileLogger.java

@@ -0,0 +1,27 @@
+package edu.wpi.first.util;
+
+import edu.wpi.first.util.datalog.DataLog;
+
+/**
+ * A class version of `tail -f`, otherwise known as `tail -f` at home. Watches a file and puts the data into a data log.  Only works on Linux-based platforms.
+ */
+public class FileLogger implements AutoCloseable {
+  private long m_impl;
+
+  /**
+   * Construct a FileLogger. When the specified file is modified, appended data will be
+   * appended to the specified data log.
+   *
+   * @param file The path to the file.
+   * @param log A data log.
+   * @param key The log key to append data to.
+   */
+    public FileLogger(String file, DataLog log, String key) {
+        m_impl = WPIUtilJNI.createFileLogger(file, log, key);
+    }
+
+    @Override
+    public void close()  {
+        WPIUtilJNI.freeFileLogger(m_impl);
+    }
+}

wpiutil/src/main/java/edu/wpi/first/util/WPIUtilJNI.java

@@ -8,6 +8,8 @@
 import java.nio.ByteBuffer;
 import java.util.concurrent.atomic.AtomicBoolean;
 
+import edu.wpi.first.util.datalog.DataLog;
+
 /** WPIUtil JNI. */
 public class WPIUtilJNI {
   static boolean libraryLoaded = false;
@@ -217,6 +219,23 @@ public static native boolean waitForObjectTimeout(int handle, double timeout)
   public static native int[] waitForObjectsTimeout(int[] handles, double timeout)
       throws InterruptedException;
 
+  /**
+   * Create a native FileLogger. When the specified file is modified, appended data will be
+   * appended to the specified data log.
+   *
+   * @param file The path to the file.
+   * @param log A data log.
+   * @param key The log key to append data to.
+   */
+  public static native long createFileLogger(String file, DataLog log, String key);
+
+  /**
+   * Free a native FileLogger. This causes the FileLogger to stop appending data to the log.
+   *
+   * @param fileTail The FileLogger handle.
+   */
+  public static native void freeFileLogger(long fileTail);
+
   /** Utility class. */
   protected WPIUtilJNI() {}
 }

wpiutil/src/main/native/cpp/FileLogger.cpp

@@ -0,0 +1,34 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "wpi/FileLogger.h"
+
+namespace wpi {
+FileLogger::FileLogger(std::string_view file,
+                   std::function<void(std::string_view)> callback)
+#ifdef __linux__
+    : m_fileHandle{open(file.data(), O_RDONLY)},
+      m_inotifyHandle{inotify_init()},
+      m_inotifyWatchHandle{
+          inotify_add_watch(m_inotifyHandle, file.data(), IN_MODIFY)},
+      m_thread{[=, this] {
+        char buf[4000];
+        struct inotify_event ev;
+        int len = 0;
+        while ((len = read(m_inotifyHandle, &ev, sizeof(ev))) > 0) {
+          int buf_len = read(m_fileHandle, buf, sizeof(buf));
+          callback(std::string_view{buf, buf_len});
+        }
+      }}
+#endif
+{}
+FileLogger::~FileLogger() {
+#ifdef __linux__
+  inotify_rm_watch(m_inotifyHandle, m_inotifyWatchHandle);
+  close(m_inotifyHandle);
+  close(m_fileHandle);
+  m_thread.join();
+#endif
+}
+}  // namespace wpi