//    OpenVPN -- An application to securely tunnel IP networks
//               over a single port, with support for SSL/TLS-based
//               session authentication and key exchange,
//               packet encryption, packet authentication, and
//               packet compression.
//
//    Copyright (C) 2012-2020 OpenVPN Inc.
//
//    This program is free software: you can redistribute it and/or modify
//    it under the terms of the GNU Affero General Public License Version 3
//    as published by the Free Software Foundation.
//
//    This program is distributed in the hope that it will be useful,
//    but WITHOUT ANY WARRANTY; without even the implied warranty of
//    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//    GNU Affero General Public License for more details.
//
//    You should have received a copy of the GNU Affero General Public License
//    along with this program in the COPYING file.
//    If not, see <http://www.gnu.org/licenses/>.

#ifndef OPENVPN_BUFFER_BUFREAD_H
#define OPENVPN_BUFFER_BUFREAD_H

#include <unistd.h>
#include <errno.h>

#include <string>
#include <cstring>

#include <openvpn/common/size.hpp>
#include <openvpn/common/exception.hpp>
#include <openvpn/common/strerror.hpp>
#include <openvpn/buffer/buflist.hpp>

namespace openvpn {
  OPENVPN_EXCEPTION(buf_read_error);

  inline bool buf_read(const int fd, Buffer& buf, const std::string& title)
  {
    const ssize_t status = ::read(fd, buf.data_end(), buf.remaining(0));
    if (status < 0)
      {
	const int eno = errno;
	OPENVPN_THROW(buf_read_error, "on " << title << " : " << strerror_str(eno));
      }
    else if (!status)
      return false;
    buf.inc_size(status);
    return true;
  }

  inline BufferList buf_read(const int fd, const std::string& title)
  {
    BufferList buflist;
    while (true)
      {
	BufferAllocated buf(1024, 0);
	if (!buf_read(fd, buf, title))
	  break;
	buflist.put_consume(buf);
      }
    return buflist;
  }
}

#endif