rtorrent/src/rpc/scgi_task.cc

// rTorrent - BitTorrent client
// Copyright (C) 2005-2006, Jari Sundell
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
// 
// 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 General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
//
// In addition, as a special exception, the copyright holders give
// permission to link the code of portions of this program with the
// OpenSSL library under certain conditions as described in each
// individual source file, and distribute linked combinations
// including the two.
//
// You must obey the GNU General Public License in all respects for
// all of the code used other than OpenSSL.  If you modify file(s)
// with this exception, you may extend this exception to your version
// of the file(s), but you are not obligated to do so.  If you do not
// wish to do so, delete this exception statement from your version.
// If you delete this exception statement from all source files in the
// program, then also delete it here.
//
// Contact:  Jari Sundell <jaris@ifi.uio.no>
//
//           Skomakerveien 33
//           3185 Skoppum, NORWAY

#include "config.h"

#include <rak/error_number.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <torrent/exceptions.h>
#include <torrent/poll.h>

#include "utils/socket_fd.h"

#include "control.h"
#include "globals.h"
#include "scgi.h"

namespace rpc {

void
SCgiTask::open(SCgi* parent, int fd) {
  m_parent = parent;
  m_fileDesc = fd;
  m_buffer = new char[(m_bufferSize = 2048)];
  m_position = m_buffer;

  control->poll()->open(this);
  control->poll()->insert_read(this);
  control->poll()->insert_error(this);
}

void
SCgiTask::close() {
  if (!get_fd().is_valid())
    return;

  control->poll()->remove_read(this);
  control->poll()->remove_write(this);
  control->poll()->remove_error(this);
  control->poll()->close(this);

  get_fd().close();
  get_fd().clear();

  delete [] m_buffer;
  m_buffer = NULL;
}

void
SCgiTask::event_read() {
  int bytes = ::recv(m_fileDesc, m_position, m_bufferSize - 1 - (m_position - m_buffer), 0);

  if (bytes == -1) {
    if (!rak::error_number::current().is_blocked_momentary())
      close();

    return;
  }

  m_position += bytes;
  *m_position = '\0';

  // Don't bother caching the parsed values, as we're likely to
  // receive all the data we need the first time.
  char* current;
  char* contentPos;

  int headerSize = strtol(m_buffer, &current, 0);
  int contentSize;

  if (current == m_buffer || current == m_position)
    // Need to validate the header size.
    return;

  if (*current != ':' || headerSize < 17)
    goto event_read_failed;

  if (std::distance(++current, m_position) < headerSize + 1)
    return;

  if (std::memcmp(current, "CONTENT_LENGTH", 15) != 0)
    goto event_read_failed;

  contentSize = strtol(current + 15, &contentPos, 0);

  if (*contentPos != '\0' || contentSize <= 0)
    goto event_read_failed;

  // Start of the data.
  current += headerSize + 1;

  if (std::distance(current, m_position) < contentSize)
    return;

  control->poll()->remove_read(this);
  control->poll()->insert_write(this);

  if (!m_parent->receive_call(this, current, contentSize))
    close();

  return;

 event_read_failed:
  throw torrent::internal_error("SCgiTask::event_read() fault not handled.");
}

void
SCgiTask::event_write() {
  int bytes = ::send(m_fileDesc, m_position, m_bufferSize, 0);

  if (bytes == -1) {
    if (!rak::error_number::current().is_blocked_momentary())
      close();

    return;
  }

  m_position += bytes;
  m_bufferSize -= bytes;

  if (bytes == 0 || m_bufferSize == 0)
    return close();
}

void
SCgiTask::event_error() {
  close();
}

bool
SCgiTask::receive_write(const char* buffer, uint32_t length) {
  if (length + 44 > m_bufferSize) {
    delete [] m_buffer;
    m_buffer = new char[length + 44];
  }

  // Try writing as much as possible from here, before copying
  // anything.

  m_position = m_buffer;
  m_bufferSize = length + 44;
  
  std::memcpy(m_buffer, "Status: 200 OK\r\nContent-Type: text/plain\r\n\r\n", 44);
  std::memcpy(m_buffer + 44, buffer, length);

  event_write();

  return true;
}

}