[Kernel] Add support for XFileEndOfFileInformation.

src/xenia/base/filesystem.h

@@ -88,6 +88,9 @@ class FileHandle {
   virtual bool Write(size_t file_offset, const void* buffer,
                      size_t buffer_length, size_t* out_bytes_written) = 0;
 
+  // Set length of the file in bytes.
+  virtual bool SetLength(size_t length) = 0;
+
   // Flushes any pending write buffers to the underlying filesystem.
   virtual void Flush() = 0;
 

src/xenia/base/filesystem_posix.cc

@@ -99,6 +99,9 @@ class PosixFileHandle : public FileHandle {
     *out_bytes_written = out;
     return out >= 0 ? true : false;
   }
+  bool SetLength(size_t length) override {
+    return ftruncate(handle_, length) >= 0 ? true : false;
+  }
   void Flush() override { fsync(handle_); }
 
  private:

src/xenia/base/filesystem_win.cc

@@ -115,6 +115,17 @@ class Win32FileHandle : public FileHandle {
       return false;
     }
   }
+  bool SetLength(size_t length) {
+    LARGE_INTEGER position;
+    position.QuadPart = length;
+    if (!SetFilePointerEx(handle_, position, nullptr, SEEK_SET)) {
+      return false;
+    }
+    if (!SetEndOfFile(handle_)) {
+      return false;
+    }
+    return true;
+  }
   void Flush() override { FlushFileBuffers(handle_); }
 
  private: