Small improvement

Author: mike-lischke

runtime/Cpp/runtime/src/ANTLRFileStream.cpp

@@ -9,9 +9,6 @@
 
 using namespace antlr4;
 
-ANTLRFileStream::ANTLRFileStream(): ANTLRInputStream() {
-}
-
 void ANTLRFileStream::loadFromFile(const std::string &fileName) {
   _fileName = fileName;
   if (_fileName.empty()) {

runtime/Cpp/runtime/src/ANTLRFileStream.h

@@ -14,7 +14,7 @@ namespace antlr4 {
   // TODO: this class needs testing.
   class ANTLR4CPP_PUBLIC ANTLRFileStream : public ANTLRInputStream {
   public:
-    ANTLRFileStream();
+    ANTLRFileStream() = default;
     ANTLRFileStream(const std::string &) = delete;
     ANTLRFileStream(const char *data, size_t length) = delete;
     ANTLRFileStream(std::istream &stream) = delete;

runtime/Cpp/runtime/src/ANTLRInputStream.cpp

@@ -48,7 +48,7 @@ void ANTLRInputStream::load(const std::string &input) {
 void ANTLRInputStream::load(const char *data, size_t length) {
   // Remove the UTF-8 BOM if present.
   const char *bom = "\xef\xbb\xbf";
-  if (length > 3 && strncmp(data, bom, 3) == 0)
+  if (length >= 3 && strncmp(data, bom, 3) == 0)
     _data = antlrcpp::utf8_to_utf32(data + 3, data + length);
   else
     _data = antlrcpp::utf8_to_utf32(data, data + length);