From da8910cdaf3566c17077e4846bde014500115e42 Mon Sep 17 00:00:00 2001
From: Jorj Bauer <jorj@jorj.org>
Date: Fri, 7 Jan 2022 12:50:13 -0500
Subject: [PATCH] add flush method

---
 filemanager.h                 | 4 +++-
 nix/nix-filemanager.cpp       | 5 +++++
 nix/nix-filemanager.h         | 1 +
 teensy/teensy-filemanager.cpp | 9 +++++++++
 teensy/teensy-filemanager.h   | 4 +++-
 5 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/filemanager.h b/filemanager.h
index ed1bd75..167f38a 100644
--- a/filemanager.h
+++ b/filemanager.h
@@ -141,7 +141,9 @@ class FileManager {
   virtual int write(int8_t fd, const void *buf, int nbyte) = 0;
   virtual int read(int8_t fd, void *buf, int nbyte) = 0;
   virtual int lseek(int8_t fd, int offset, int whence) = 0;
-  
+
+  virtual void flush() = 0;
+
  protected:
   volatile unsigned long fileSeekPositions[MAXFILES];
   char cachedNames[MAXFILES][MAXPATH];
diff --git a/nix/nix-filemanager.cpp b/nix/nix-filemanager.cpp
index a1c7e99..c0d686e 100644
--- a/nix/nix-filemanager.cpp
+++ b/nix/nix-filemanager.cpp
@@ -290,3 +290,8 @@ int NixFileManager::lseek(int8_t fd, int offset, int whence)
   exit(1); // this is an error condition we need to find and fix if it happens
   return -1;
 };
+
+void NixFileManager::flush()
+{
+  // No files are kept open, so there's nothing to flush
+}
diff --git a/nix/nix-filemanager.h b/nix/nix-filemanager.h
index 6300d60..e1aceb1 100644
--- a/nix/nix-filemanager.h
+++ b/nix/nix-filemanager.h
@@ -26,6 +26,7 @@ class NixFileManager : public FileManager {
   virtual int read(int8_t fd, void *buf, int nbyte);
   virtual int lseek(int8_t fd, int offset, int whence);
 
+  virtual void flush();
  private:
   int8_t numCached;
   
diff --git a/teensy/teensy-filemanager.cpp b/teensy/teensy-filemanager.cpp
index cebba02..7529823 100644
--- a/teensy/teensy-filemanager.cpp
+++ b/teensy/teensy-filemanager.cpp
@@ -300,3 +300,12 @@ int TeensyFileManager::lseek(int8_t fd, int offset, int whence)
   return -1;
 };
 
+void TeensyFileManager::flush()
+{
+  if (cacheFd == -1)
+    return;
+  
+  cacheFile.close();
+  cacheFd = -1;
+}
+
diff --git a/teensy/teensy-filemanager.h b/teensy/teensy-filemanager.h
index 21a7b29..c5d16d1 100644
--- a/teensy/teensy-filemanager.h
+++ b/teensy/teensy-filemanager.h
@@ -27,7 +27,9 @@ class TeensyFileManager : public FileManager {
   virtual int write(int8_t fd, const void *buf, int nbyte);
   virtual int read(int8_t fd, void *buf, int nbyte);
   virtual int lseek(int8_t fd, int offset, int whence);
-  
+
+  virtual void flush();
+
  private:
   bool _prepCache(int8_t fd);