faster BXParser

src/BXParser.cc

@@ -6,15 +6,37 @@
 #include <errno.h>
 
 int BXParser::get() {
-	int ch = stream_.get();
-	if (ch == '\n') {
-		line_ += 1;
-		ch_ = 1;
+	if (dataidx_ < datalen_) {
+		return buf_[dataidx_++];
+	}
+
+	dataidx_ = 0;
+	stream_.read(buf_, sizeof(buf_));
+	datalen_ = stream_.gcount();
+	if (datalen_ == 0) {
+		return EOF;
+	}
+
+	return buf_[dataidx_++];
+}
+
+int BXParser::peek() {
+	if (dataidx_ < datalen_) {
+		return buf_[dataidx_];
 	} else {
-		ch_ += 1;
+		return stream_.peek();
 	}
+}
 
-	return ch;
+int BXParser::peek2() {
+	if (dataidx_ + 1 < datalen_) { 
+		return buf_[dataidx_ + 1];
+	} else {
+		stream_.get();
+		int ch = stream_.peek();
+		stream_.unget();
+		return ch;
+	}
 }
 
 BXParser::Operator BXParser::readOperator() {

src/BXParser.h

@@ -28,10 +28,10 @@ public:
 	void parse(BXVariables &vars);
 	void parseList(const BXVariables &vars, std::vector<std::string> &values);
 
-	int peek() { return stream_.peek(); }
-	int peek2() { stream_.get(); int ch = peek(); stream_.unget(); return ch; }
 	int get();
-	void skip(char);
+	int peek();
+	int peek2();
+	void skip(char expected);
 	void skip() { get(); }
 
 	int line() const { return line_; }
@@ -62,6 +62,10 @@ private:
 	int line_;
 	int ch_;
 	std::istream &stream_;
+
+	char buf_[1024];
+	size_t dataidx_ = 0;
+	size_t datalen_ = 0;
 };
 
 class BXWriter {