Some minor optimizations to FSNodePOSIX.

src/emucore/FSNode.cxx

@@ -417,7 +417,6 @@ size_t FSNode::write(const ByteBuffer& buffer, size_t size) const
 
     out.seekp(0, std::ios::end);
     sizeWritten = static_cast<size_t>(out.tellp());
-    out.seekp(0, std::ios::beg);
   }
   else
     throw runtime_error("File open/write error");
@@ -442,7 +441,6 @@ size_t FSNode::write(const stringstream& buffer) const
 
     out.seekp(0, std::ios::end);
     sizeWritten = static_cast<size_t>(out.tellp());
-    out.seekp(0, std::ios::beg);
   }
   else
     throw runtime_error("File open/write error");

src/os/unix/FSNodePOSIX.cxx

@@ -15,8 +15,6 @@
 // this file, and for a DISCLAIMER OF ALL WARRANTIES.
 //============================================================================
 
-#include "TimerManager.hxx"
-
 #if defined(RETRON77)
   #define ROOT_DIR "/mnt/games/"
 #else
@@ -39,9 +37,8 @@ FSNodePOSIX::FSNodePOSIX(const string& path, bool verify)
   // Expand '~' to the HOME environment variable
   if(_path[0] == '~')
   {
-    const char* home = std::getenv("HOME");  // NOLINT (not thread safe)
-    if (home != nullptr)
-      _path.replace(0, 1, home);
+    if (ourHomeDir != nullptr)
+      _path.replace(0, 1, ourHomeDir);
   }
   // Get absolute path (only used for relative directories)
   else if(_path[0] == '.')
@@ -62,7 +59,7 @@ void FSNodePOSIX::setFlags()
 {
   struct stat st;
 
-  _isValid = (0 == stat(_path.c_str(), &st));
+  _isValid = stat(_path.c_str(), &st) == 0;
   if(_isValid)
   {
     _isDirectory = S_ISDIR(st.st_mode);
@@ -80,8 +77,7 @@ void FSNodePOSIX::setFlags()
 string FSNodePOSIX::getShortPath() const
 {
   // If the path starts with the home directory, replace it with '~'
-  const char* env_home = std::getenv("HOME");  // NOLINT (not thread safe)
-  const string& home = env_home != nullptr ? env_home : EmptyString;
+  const string& home = ourHomeDir != nullptr ? ourHomeDir : EmptyString;
 
   if(home != EmptyString && BSPF::startsWithIgnoreCase(_path, home))
   {
@@ -94,12 +90,31 @@ string FSNodePOSIX::getShortPath() const
   return _path;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+size_t FSNodePOSIX::getSize() const
+{
+  struct stat st;
+  return (stat(_path.c_str(), &st) == 0) ? st.st_size : 0;
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool FSNodePOSIX::hasParent() const
 {
   return !_path.empty() && _path != ROOT_DIR;
 }
 
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+AbstractFSNodePtr FSNodePOSIX::getParent() const
+{
+  if (_path == ROOT_DIR)
+    return nullptr;
+
+  const char* start = _path.c_str();
+  const char* end = lastPathComponent(_path);
+
+  return make_unique<FSNodePOSIX>(string(start, static_cast<size_t>(end - start)));
+}
+
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool FSNodePOSIX::getChildren(AbstractFSList& myList, ListMode mode) const
 {
@@ -172,13 +187,6 @@ bool FSNodePOSIX::getChildren(AbstractFSList& myList, ListMode mode) const
   return true;
 }
 
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-size_t FSNodePOSIX::getSize() const
-{
-  struct stat st;
-  return (stat(_path.c_str(), &st) == 0) ? st.st_size : 0;
-}
-
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 bool FSNodePOSIX::makeDir()
 {
@@ -228,13 +236,4 @@ bool FSNodePOSIX::rename(const string& newfile)
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-AbstractFSNodePtr FSNodePOSIX::getParent() const
-{
-  if (_path == ROOT_DIR)
-    return nullptr;
-
-  const char* start = _path.c_str();
-  const char* end = lastPathComponent(_path);
-
-  return make_unique<FSNodePOSIX>(string(start, static_cast<size_t>(end - start)));
-}
+const char* FSNodePOSIX::ourHomeDir = std::getenv("HOME"); // NOLINT (not thread safe)

src/os/unix/FSNodePOSIX.hxx

@@ -65,7 +65,6 @@ class FSNodePOSIX : public AbstractFSNode
     void setName(const string& name) override { _displayName = name; }
     const string& getPath() const override { return _path; }
     string getShortPath() const override;
-    bool hasParent() const override;
     bool isDirectory() const override { return _isDirectory; }
     bool isFile() const override      { return _isFile;      }
     bool isReadable() const override  { return access(_path.c_str(), R_OK) == 0; }
@@ -74,15 +73,9 @@ class FSNodePOSIX : public AbstractFSNode
     bool rename(const string& newfile) override;
 
     size_t getSize() const override;
-    bool getChildren(AbstractFSList& list, ListMode mode) const override;
+    bool hasParent() const override;
     AbstractFSNodePtr getParent() const override;
-
-  protected:
-    string _path;
-    string _displayName;
-    bool _isValid{true};
-    bool _isFile{false};
-    bool _isDirectory{true};
+    bool getChildren(AbstractFSList& list, ListMode mode) const override;
 
   private:
     /**
@@ -90,6 +83,12 @@ class FSNodePOSIX : public AbstractFSNode
      * using the stat() function.
      */
     void setFlags();
+
+  private:
+    string _path, _displayName;
+    bool _isValid{true}, _isFile{false}, _isDirectory{true};
+
+    static const char* ourHomeDir;
 };
 
 #endif