compiler/cpp/src/parse/t_type.h

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#ifndef T_TYPE_H
#define T_TYPE_H

#include <string>
#include <map>
#include <cstring>
#include <stdint.h>
#include "t_doc.h"

class t_program;

/**
 * Generic representation of a thrift type. These objects are used by the
 * parser module to build up a tree of object that are all explicitly typed.
 * The generic t_type class exports a variety of useful methods that are
 * used by the code generator to branch based upon different handling for the
 * various types.
 *
 */
class t_type : public t_doc {
 public:
  virtual ~t_type() {}

  virtual void set_name(const std::string& name) {
    name_ = name;
  }

  virtual const std::string& get_name() const {
    return name_;
  }

  virtual bool is_void()      const { return false; }
  virtual bool is_base_type() const { return false; }
  virtual bool is_string()    const { return false; }
  virtual bool is_bool()      const { return false; }
  virtual bool is_typedef()   const { return false; }
  virtual bool is_enum()      const { return false; }
  virtual bool is_struct()    const { return false; }
  virtual bool is_xception()  const { return false; }
  virtual bool is_container() const { return false; }
  virtual bool is_list()      const { return false; }
  virtual bool is_set()       const { return false; }
  virtual bool is_map()       const { return false; }
  virtual bool is_service()   const { return false; }

  t_program* get_program() {
    return program_;
  }

  t_type* get_true_type();

  // Return a string that uniquely identifies this type
  // from any other thrift type in the world, as far as
  // TDenseProtocol is concerned.
  // We don't cache this, which is a little sloppy,
  // but the compiler is so fast that it doesn't really matter.
  virtual std::string get_fingerprint_material() const = 0;

  // Fingerprint should change whenever (and only when)
  // the encoding via TDenseProtocol changes.
  static const int fingerprint_len = 16;

  // Call this before trying get_*_fingerprint().
  virtual void generate_fingerprint();

  bool has_fingerprint() const {
    for (int i = 0; i < fingerprint_len; i++) {
      if (fingerprint_[i] != 0) {
        return true;
      }
    }
    return false;
  }

  const uint8_t* get_binary_fingerprint() const {
    return fingerprint_;
  }

  std::string get_ascii_fingerprint() const {
    std::string rv;
    const uint8_t* fp = get_binary_fingerprint();
    for (int i = 0; i < fingerprint_len; i++) {
      rv += byte_to_hex(fp[i]);
    }
    return rv;
  }

  // This function will break (maybe badly) unless 0 <= num <= 16.
  static char nybble_to_xdigit(int num) {
    if (num < 10) {
      return '0' + num;
    } else {
      return 'A' + num - 10;
    }
  }

  static std::string byte_to_hex(uint8_t byte) {
    std::string rv;
    rv += nybble_to_xdigit(byte >> 4);
    rv += nybble_to_xdigit(byte & 0x0f);
    return rv;
  }

  std::map<std::string, std::string> annotations_;

 protected:
  t_type() :
    program_(NULL)
  {
    memset(fingerprint_, 0, sizeof(fingerprint_));
  }

  t_type(t_program* program) :
    program_(program)
  {
    memset(fingerprint_, 0, sizeof(fingerprint_));
  }

  t_type(t_program* program, std::string name) :
    program_(program),
    name_(name)
  {
    memset(fingerprint_, 0, sizeof(fingerprint_));
  }

  t_type(std::string name) :
    program_(NULL),
    name_(name)
  {
    memset(fingerprint_, 0, sizeof(fingerprint_));
  }

  t_program* program_;
  std::string name_;

  uint8_t fingerprint_[fingerprint_len];
};


/**
 * Placeholder struct for returning the key and value of an annotation
 * during parsing.
 */
struct t_annotation {
  std::string key;
  std::string val;
};

#endif