add antlr

lib/antlr4/include/ANTLRInputStream.h

@@ -0,0 +1,69 @@
+/* Copyright (c) 2012-2017 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+
+#pragma once
+
+#include "CharStream.h"
+
+namespace antlr4 {
+
+  // Vacuum all input from a stream and then treat it
+  // like a string. Can also pass in a string or char[] to use.
+  // Input is expected to be encoded in UTF-8 and converted to UTF-32 internally.
+  class ANTLR4CPP_PUBLIC ANTLRInputStream : public CharStream {
+  protected:
+    /// The data being scanned.
+    // UTF-32
+    UTF32String _data;
+
+    /// 0..n-1 index into string of next char </summary>
+    size_t p;
+
+  public:
+    /// What is name or source of this char stream?
+    std::string name;
+
+    ANTLRInputStream(const std::string &input = "");
+    ANTLRInputStream(const char data_[], size_t numberOfActualCharsInArray);
+    ANTLRInputStream(std::istream &stream);
+
+    virtual void load(const std::string &input);
+    virtual void load(std::istream &stream);
+
+    /// Reset the stream so that it's in the same state it was
+    /// when the object was created *except* the data array is not
+    /// touched.
+    virtual void reset();
+    virtual void consume() override;
+    virtual size_t LA(ssize_t i) override;
+    virtual size_t LT(ssize_t i);
+
+    /// <summary>
+    /// Return the current input symbol index 0..n where n indicates the
+    ///  last symbol has been read.  The index is the index of char to
+    ///  be returned from LA(1).
+    /// </summary>
+    virtual size_t index() override;
+    virtual size_t size() override;
+
+    /// <summary>
+    /// mark/release do nothing; we have entire buffer </summary>
+    virtual ssize_t mark() override;
+    virtual void release(ssize_t marker) override;
+
+    /// <summary>
+    /// consume() ahead until p==index; can't just set p=index as we must
+    ///  update line and charPositionInLine. If we seek backwards, just set p
+    /// </summary>
+    virtual void seek(size_t index) override;
+    virtual std::string getText(const misc::Interval &interval) override;
+    virtual std::string getSourceName() const override;
+    virtual std::string toString() const override;
+
+  private:
+    void InitializeInstanceFields();
+  };
+
+} // namespace antlr4