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// Copyright (c) 2005, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author: Sanjay Ghemawat

#ifndef _PCRECPPARG_H
#define _PCRECPPARG_H

#include <stdlib.h>    // for NULL
#include <string>

#include <pcre2.h>

namespace pcrecpp {

class StringPiece;

// Hex/Octal/Binary?

// Special class for parsing into objects that define a ParseFrom() method
template <class T>
class _RE_MatchObject {
 public:
  static inline bool Parse(const char* str, int n, void* dest) {
    if (dest == NULL) return true;
    T* object = reinterpret_cast<T*>(dest);
    return object->ParseFrom(str, n);
  }
};

class Arg {
 public:
  // Empty constructor so we can declare arrays of Arg
  Arg();

  // Constructor specially designed for NULL arguments
  Arg(void*);

  typedef bool (*Parser)(const char* str, int n, void* dest);

// Type-specific parsers
#define PCRE_MAKE_PARSER(type,name)                             \
  Arg(type* p) : arg_(p), parser_(name) { }                     \
  Arg(type* p, Parser parser) : arg_(p), parser_(parser) { }


  PCRE_MAKE_PARSER(char,               parse_char);
  PCRE_MAKE_PARSER(unsigned char,      parse_uchar);
  PCRE_MAKE_PARSER(short,              parse_short);
  PCRE_MAKE_PARSER(unsigned short,     parse_ushort);
  PCRE_MAKE_PARSER(int,                parse_int);
  PCRE_MAKE_PARSER(unsigned int,       parse_uint);
  PCRE_MAKE_PARSER(long,               parse_long);
  PCRE_MAKE_PARSER(unsigned long,      parse_ulong);
#if 1
  PCRE_MAKE_PARSER(long long,          parse_longlong);
#endif
#if 1
  PCRE_MAKE_PARSER(unsigned long long, parse_ulonglong);
#endif
  PCRE_MAKE_PARSER(float,              parse_float);
  PCRE_MAKE_PARSER(double,             parse_double);
  PCRE_MAKE_PARSER(std::string,        parse_string);
  PCRE_MAKE_PARSER(StringPiece,        parse_stringpiece);

#undef PCRE_MAKE_PARSER

  // Generic constructor
  template <class T> Arg(T*, Parser parser);
  // Generic constructor template
  template <class T> Arg(T* p)
    : arg_(p), parser_(_RE_MatchObject<T>::Parse) {
  }

  // Parse the data
  bool Parse(const char* str, int n) const;

 private:
  void*         arg_;
  Parser        parser_;

  static bool parse_null          (const char* str, int n, void* dest);
  static bool parse_char          (const char* str, int n, void* dest);
  static bool parse_uchar         (const char* str, int n, void* dest);
  static bool parse_float         (const char* str, int n, void* dest);
  static bool parse_double        (const char* str, int n, void* dest);
  static bool parse_string        (const char* str, int n, void* dest);
  static bool parse_stringpiece   (const char* str, int n, void* dest);

#define PCRE_DECLARE_INTEGER_PARSER(name)                                   \
 private:                                                                   \
  static bool parse_ ## name(const char* str, int n, void* dest);           \
  static bool parse_ ## name ## _radix(                                     \
    const char* str, int n, void* dest, int radix);                         \
 public:                                                                    \
  static bool parse_ ## name ## _hex(const char* str, int n, void* dest);   \
  static bool parse_ ## name ## _octal(const char* str, int n, void* dest); \
  static bool parse_ ## name ## _cradix(const char* str, int n, void* dest)

  PCRE_DECLARE_INTEGER_PARSER(short);
  PCRE_DECLARE_INTEGER_PARSER(ushort);
  PCRE_DECLARE_INTEGER_PARSER(int);
  PCRE_DECLARE_INTEGER_PARSER(uint);
  PCRE_DECLARE_INTEGER_PARSER(long);
  PCRE_DECLARE_INTEGER_PARSER(ulong);
  PCRE_DECLARE_INTEGER_PARSER(longlong);
  PCRE_DECLARE_INTEGER_PARSER(ulonglong);

#undef PCRE_DECLARE_INTEGER_PARSER
};

inline Arg::Arg() : arg_(NULL), parser_(parse_null) { }
inline Arg::Arg(void* p) : arg_(p), parser_(parse_null) { }

inline bool Arg::Parse(const char* str, int n) const {
  return (*parser_)(str, n, arg_);
}

// This part of the parser, appropriate only for ints, deals with bases
#define MAKE_INTEGER_PARSER(type, name) \
  inline Arg Hex(type* ptr) { \
    return Arg(ptr, Arg::parse_ ## name ## _hex); } \
  inline Arg Octal(type* ptr) { \
    return Arg(ptr, Arg::parse_ ## name ## _octal); } \
  inline Arg CRadix(type* ptr) { \
    return Arg(ptr, Arg::parse_ ## name ## _cradix); }

MAKE_INTEGER_PARSER(short,              short)     /*                        */
MAKE_INTEGER_PARSER(unsigned short,     ushort)    /*                        */
MAKE_INTEGER_PARSER(int,                int)       /* Don't use semicolons   */
MAKE_INTEGER_PARSER(unsigned int,       uint)      /* after these statement  */
MAKE_INTEGER_PARSER(long,               long)      /* because they can cause */
MAKE_INTEGER_PARSER(unsigned long,      ulong)     /* compiler warnings if   */
#if 1                          /* the checking level is  */
MAKE_INTEGER_PARSER(long long,          longlong)  /* turned up high enough. */
#endif                                             /*                        */
#if 1                         /*                        */
MAKE_INTEGER_PARSER(unsigned long long, ulonglong) /*                        */
#endif

#undef PCRE_IS_SET
#undef PCRE_SET_OR_CLEAR
#undef MAKE_INTEGER_PARSER

template<typename ARG>
inline Arg wrap_arg(ARG && any) {
  return Arg(any);
}

inline Arg const & wrap_arg(Arg const & arg) {
  return arg;
}

template<typename ... ARGS>
struct Args;

template<typename HEAD, typename ... TAIL>
struct Args<HEAD, TAIL...> {
  typedef Args<TAIL...> next;
  constexpr static unsigned count() {
    return 1 + next::count();
  }
  template<typename _HEAD, typename ... _TAIL>
  inline static void arrayify(Arg * ptr, _HEAD && head, _TAIL && ... tail) {
    *ptr++ = wrap_arg(head);
    next::arrayify(ptr, tail...);
  }
};

template<>
struct Args<> {
  constexpr static unsigned count() {
    return 0;
  }
  inline static void arrayify(Arg *) {
  }
};

}   // namespace pcrecpp


#endif /* _PCRECPPARG_H */