ostream.h

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/*
 Formatting library for C++ - std::ostream support

 Copyright (c) 2012 - 2016, Victor Zverovich
 All rights reserved.

 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are met:

 1. Redistributions of source code must retain the above copyright notice, this
    list of conditions and the following disclaimer.
 2. 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.

 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.
 */

#ifndef FMT_OSTREAM_H_
#define FMT_OSTREAM_H_

#include "system/fmt/format.h"
#include <ostream>

namespace fmt {

namespace internal {

template <class Char>
class FormatBuf : public std::basic_streambuf<Char> {
 private:
  typedef typename std::basic_streambuf<Char>::int_type int_type;
  typedef typename std::basic_streambuf<Char>::traits_type traits_type;

  Buffer<Char> &buffer_;
  Char *start_;

 public:
  FormatBuf(Buffer<Char> &buffer) : buffer_(buffer), start_(&buffer[0]) {
    this->setp(start_, start_ + buffer_.capacity());
  }

  int_type overflow(int_type ch = traits_type::eof()) {
    if (!traits_type::eq_int_type(ch, traits_type::eof())) {
      size_t buf_size = size();
      buffer_.resize(buf_size);
      buffer_.reserve(buf_size * 2);

      start_ = &buffer_[0];
      start_[buf_size] = traits_type::to_char_type(ch);
      this->setp(start_+ buf_size + 1, start_ + buf_size * 2);
    }
    return ch;
  }

  size_t size() const {
    return to_unsigned(this->pptr() - start_);
  }
};

Yes &convert(std::ostream &);

struct DummyStream : std::ostream {
  DummyStream();  // Suppress a bogus warning in MSVC.
  // Hide all operator<< overloads from std::ostream.
  void operator<<(Null<>);
};

No &operator<<(std::ostream &, int);

template<typename T>
struct ConvertToIntImpl<T, true> {
  // Convert to int only if T doesn't have an overloaded operator<<.
  enum {
    value = sizeof(convert(get<DummyStream>() << get<T>())) == sizeof(No)
  };
};
}  // namespace internal

// Formats a value.
template <typename Char, typename ArgFormatter, typename T>
void format(BasicFormatter<Char, ArgFormatter> &f,
            const Char *&format_str, const T &value) {
  internal::MemoryBuffer<Char, internal::INLINE_BUFFER_SIZE> buffer;

  internal::FormatBuf<Char> format_buf(buffer);
  std::basic_ostream<Char> output(&format_buf);
  output << value;

  BasicStringRef<Char> str(&buffer[0], format_buf.size());
  typedef internal::MakeArg< BasicFormatter<Char> > MakeArg;
  format_str = f.format(format_str, MakeArg(str));
}

/**
  \rst
  Prints formatted data to the stream *os*.

  **Example**::

    print(cerr, "Don't {}!", "panic");
  \endrst
 */
FMT_API void print(std::ostream &os, CStringRef format_str, ArgList args);
FMT_VARIADIC(void, print, std::ostream &, CStringRef)

/**
  \rst
  Prints formatted data to the stream *os*.

  **Example**::

    fprintf(cerr, "Don't %s!", "panic");
  \endrst
 */
FMT_API int fprintf(std::ostream &os, CStringRef format_str, ArgList args);
FMT_VARIADIC(int, fprintf, std::ostream &, CStringRef)
}  // namespace fmt

#ifdef FMT_HEADER_ONLY
# include "ostream.cc"
#endif

#endif  // FMT_OSTREAM_H_