spdylay/examples/spdyd.cc

/*
 * Spdylay - SPDY Library
 *
 * Copyright (c) 2012 Tatsuhiro Tsujikawa
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netdb.h>
#include <unistd.h>
#include <fcntl.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <signal.h>
#include <getopt.h>

#include <cassert>
#include <cstdio>
#include <cerrno>
#include <cstdlib>
#include <cstring>
#include <string>
#include <iostream>
#include <string>
#include <set>
#include <iomanip>
#include <fstream>
#include <map>
#include <vector>
#include <sstream>

#include <openssl/ssl.h>
#include <openssl/err.h>
#include <spdylay/spdylay.h>

#include "spdylay_ssl.h"
#include "uri.h"
#include "util.h"
#include "EventPoll.h"

namespace spdylay {

struct Config {
  std::string htdocs;
  bool verbose;
  bool daemon;
  uint16_t port;
  std::string private_key_file;
  std::string cert_file;
  Config(): verbose(false), daemon(false), port(0) {}
};

extern bool ssl_debug;

namespace {
Config config;
const std::string STATUS_200 = "200 OK";
const std::string STATUS_304 = "304 Not Modified";
const std::string STATUS_400 = "400 Bad Request";
const std::string STATUS_404 = "404 Not Found";
const std::string DEFAULT_HTML = "index.html";
const std::string SPDYD_SERVER = "spdyd spdylay/"SPDYLAY_VERSION;
} // namespace

struct Request {
  int32_t stream_id;
  std::vector<std::pair<std::string, std::string> > headers;
  int file;
  Request(int32_t stream_id)
    : stream_id(stream_id), file(-1) {}
  ~Request()
  {
    if(file != -1) {
      close(file);
    }
  }
};

class Sessions;

class EventHandler {
public:
  EventHandler() : mark_del_(false) {}
  virtual ~EventHandler() {}
  virtual int execute(Sessions *sessions) = 0;
  virtual bool want_read() = 0;
  virtual bool want_write() = 0;
  virtual int fd() const = 0;
  virtual bool finish() = 0;
  bool mark_del()
  {
    return mark_del_;
  }
  void mark_del(bool d)
  {
    mark_del_ = d;
  }
private:
  bool mark_del_;
};

namespace {
void on_close(Sessions &sessions, EventHandler *hd);
} // namespace

class Sessions {
public:
  Sessions(int max_events, SSL_CTX *ssl_ctx)
    : eventPoll_(max_events),
      ssl_ctx_(ssl_ctx)
  {}
  ~Sessions()
  {
    for(std::set<EventHandler*>::iterator i = handlers_.begin(),
          eoi = handlers_.end(); i != eoi; ++i) {
      on_close(*this, *i);
      delete *i;
    }
    SSL_CTX_free(ssl_ctx_);
  }
  void add_handler(EventHandler *handler)
  {
    handlers_.insert(handler);
  }
  void remove_handler(EventHandler *handler)
  {
    handlers_.erase(handler);
  }
  SSL* ssl_session_new(int fd)
  {
    SSL *ssl = SSL_new(ssl_ctx_);
    if(SSL_set_fd(ssl, fd) == 0) {
      SSL_free(ssl);
      return 0;
    }
    return ssl;
  }
  int add_poll(EventHandler *handler)
  {
    return update_poll_internal(handler, EP_ADD);
  }
  int mod_poll(EventHandler *handler)
  {
    return update_poll_internal(handler, EP_MOD);
  }
  int poll(int timeout)
  {
    return eventPoll_.poll(timeout);
  }
  void* get_user_data(int p)
  {
    return eventPoll_.get_user_data(p);
  }
  int get_events(int p)
  {
    return eventPoll_.get_events(p);
  }
private:
  int update_poll_internal(EventHandler *handler, int op)
  {
    int events = 0;
    if(handler->want_read()) {
      events |= EP_POLLIN;
    }
    if(handler->want_write()) {
      events |= EP_POLLOUT;
    }
    return eventPoll_.ctl_event(op, handler->fd(), events, handler);
  }

  std::set<EventHandler*> handlers_;
  EventPoll eventPoll_;
  SSL_CTX *ssl_ctx_;
};

namespace {
void print_session_id(int64_t id)
{
  std::cout << "[id=" << id << "] ";
}
} // namespace

namespace {
void on_session_closed(int64_t session_id)
{
  if(config.verbose) {
    print_session_id(session_id);
    print_timer();
    std::cout << " closed" << std::endl;
  }
}
} // namespace

class SpdyEventHandler : public EventHandler {
public:
  SpdyEventHandler(int fd, SSL *ssl, const spdylay_session_callbacks *callbacks,
                   int64_t session_id)
    : fd_(fd), ssl_(ssl), session_id_(session_id), want_write_(false)
  {
    spdylay_session_server_new(&session_, callbacks, this);
  }
    
  virtual ~SpdyEventHandler()
  {
    on_session_closed(session_id_);
    spdylay_session_del(session_);
    for(std::map<int32_t, Request*>::iterator i = id2req_.begin(),
          eoi = id2req_.end(); i != eoi; ++i) {
      delete (*i).second;
    }
    SSL_shutdown(ssl_);
    SSL_free(ssl_);
    shutdown(fd_, SHUT_WR);
    close(fd_);
  }
  virtual int execute(Sessions *sessions)
  {
    int r;
    r = spdylay_session_recv(session_);
    if(r == 0) {
      r = spdylay_session_send(session_);
    }
    return r;
  }
  virtual bool want_read()
  {
    return spdylay_session_want_read(session_);
  }
  virtual bool want_write()
  {
    return spdylay_session_want_write(session_) || want_write_;
  }
  virtual int fd() const
  {
    return fd_;
  }
  virtual bool finish()
  {
    return !want_read() && !want_write();
  }
  ssize_t send_data(const uint8_t *data, size_t len, int flags)
  {
    ssize_t r;
    r = SSL_write(ssl_, data, len);
    return r;
  }

  ssize_t recv_data(uint8_t *data, size_t len, int flags)
  {
    ssize_t r;
    want_write_ = false;
    r = SSL_read(ssl_, data, len);
    if(r < 0) {
      if(SSL_get_error(ssl_, r) == SSL_ERROR_WANT_WRITE) {
        want_write_ = true;
      }
    }
    return r;
  }
  bool would_block(int r)
  {
    int e = SSL_get_error(ssl_, r);
    return e == SSL_ERROR_WANT_WRITE || e == SSL_ERROR_WANT_READ;
  }
  int submit_file_response(const std::string& status,
                           int32_t stream_id,
                           time_t last_modified,
                           off_t file_length,
                           spdylay_data_provider *data_prd)
  {
    const char *nv[] = {
      "status", status.c_str(),
      "version", "HTTP/1.1",
      "server", SPDYD_SERVER.c_str(),
      "content-length", util::to_str(file_length).c_str(),
      "cache-control", "max-age=3600",
      "date", util::http_date(time(0)).c_str(),
      0, 0,
      0
    };
    if(last_modified != 0) {
      nv[12] = "last-modified";
      nv[13] = util::http_date(last_modified).c_str();
    }
    return spdylay_submit_response(session_, stream_id, nv, data_prd);
  }
  int submit_response(const std::string& status,
                      int32_t stream_id,
                      spdylay_data_provider *data_prd)
  {
    const char *nv[] = {
      "status", status.c_str(),
      "version", "HTTP/1.1",
      "server", SPDYD_SERVER.c_str(),
      0
    };
    return spdylay_submit_response(session_, stream_id, nv, data_prd);
  }
  void add_stream(int32_t stream_id, Request *req)
  {
    id2req_[stream_id] = req;
  }
  void remove_stream(int32_t stream_id)
  {
    Request *req = id2req_[stream_id];
    id2req_.erase(stream_id);
    delete req;
  }
  Request* get_stream(int32_t stream_id)
  {
    return id2req_[stream_id];
  }
  int64_t session_id() const
  {
    return session_id_;
  }
private:
  spdylay_session *session_;
  int fd_;
  SSL* ssl_;
  int64_t session_id_;
  bool want_write_;
  std::map<int32_t, Request*> id2req_;
};

namespace {
ssize_t hd_send_callback(spdylay_session *session,
                         const uint8_t *data, size_t len, int flags,
                         void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  ssize_t r = hd->send_data(data, len, flags);
  if(r < 0) {
    if(hd->would_block(r)) {
      r = SPDYLAY_ERR_WOULDBLOCK;
    } else {
      r = SPDYLAY_ERR_CALLBACK_FAILURE;
    }
  }
  return r;
}
} // namespace

namespace {
ssize_t hd_recv_callback(spdylay_session *session,
                         uint8_t *data, size_t len, int flags, void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  ssize_t r = hd->recv_data(data, len, flags);
  if(r < 0) {
    if(hd->would_block(r)) {
      r = SPDYLAY_ERR_WOULDBLOCK;
    } else {
      r = SPDYLAY_ERR_CALLBACK_FAILURE;
    }
  } else if(r == 0) {
    r = SPDYLAY_ERR_CALLBACK_FAILURE;
  }
  return r;
}
} // namespace

namespace {
ssize_t file_read_callback
(spdylay_session *session, uint8_t *buf, size_t length, int *eof,
 spdylay_data_source *source, void *user_data)
{
  int fd = source->fd;
  ssize_t r;
  while((r = read(fd, buf, length)) == -1 && errno == EINTR);
  if(r == -1) {
    return SPDYLAY_ERR_CALLBACK_FAILURE;
  } else {
    if(r == 0) {
      *eof = 1;
    }
    return r;
  }
}
} // namespace

namespace {
bool check_url(const std::string& url)
{
  // We don't like '\' in url.
  return !url.empty() && url[0] == '/' &&
    url.find('\\') == std::string::npos &&
    url.find("/../") == std::string::npos &&
    url.find("/./") == std::string::npos &&
    !util::endsWith(url, "/..") && !util::endsWith(url, "/.");
}
} // namespace

namespace {
void prepare_status_response(Request *req, SpdyEventHandler *hd,
                             const std::string& status)
{
  int pipefd[2];
  if(pipe(pipefd) == -1) {
    hd->submit_response(status, req->stream_id, 0);
  } else {
    std::stringstream ss;
    ss << "<html><head><title>" << status << "</title></head><body>"
       << "<h1>" << status << "</h1>"
       << "<hr>"
       << "<address>" << SPDYD_SERVER << " at port " << config.port
       << "</address>"
       << "</body></html>";
    std::string body = ss.str();
    write(pipefd[1], body.c_str(), body.size());
    close(pipefd[1]);

    req->file = pipefd[0];
    spdylay_data_provider data_prd;
    data_prd.source.fd = pipefd[0];
    data_prd.read_callback = file_read_callback;
    hd->submit_file_response(status, req->stream_id, 0, body.size(), &data_prd);
  }
}
} // namespace

namespace {
void prepare_response(Request *req, SpdyEventHandler *hd)
{
  std::string url;
  bool url_found = false;
  bool method_found = false;
  bool scheme_found = false;
  bool version_found = false;
  time_t last_mod;
  bool last_mod_found = false;
  for(int i = 0; i < (int)req->headers.size(); ++i) {
    const std::string &field = req->headers[i].first;
    const std::string &value = req->headers[i].second;
    if(!url_found && field == "url") {
      url_found = true;
      url = value;
    } else if(field == "method") {
      method_found = true;
    } else if(field == "scheme") {
      scheme_found = true;
    } else if(field == "version") {
      version_found = true;
    } else if(!last_mod_found && field == "if-modified-since") {
      last_mod_found = true;
      last_mod = util::parse_http_date(value);
    }
  }
  if(!url_found || !method_found || !scheme_found || !version_found) {
    prepare_status_response(req, hd, STATUS_400);
    return;
  }
  std::string::size_type query_pos = url.find("?");
  if(query_pos != std::string::npos) {
    url = url.substr(0, query_pos);
  }
  url = util::percentDecode(url.begin(), url.end());
  if(!check_url(url)) {
    prepare_status_response(req, hd, STATUS_404);
    return;
  }
  std::string path = config.htdocs+url;
  if(path[path.size()-1] == '/') {
    path += DEFAULT_HTML;
  }
  int file = open(path.c_str(), O_RDONLY);
  if(file == -1) {
    prepare_status_response(req, hd, STATUS_404);
  } else {
    struct stat buf;
    if(fstat(file, &buf) == -1) {
      close(file);
      prepare_status_response(req, hd, STATUS_404);
    } else {
      req->file = file;
      spdylay_data_provider data_prd;
      data_prd.source.fd = file;
      data_prd.read_callback = file_read_callback;
      if(last_mod_found && buf.st_mtime <= last_mod) {
        prepare_status_response(req, hd, STATUS_304);
      } else {
        hd->submit_file_response(STATUS_200, req->stream_id, buf.st_mtime,
                                 buf.st_size, &data_prd);
      }
    }
  }
}
} // namespace

namespace {
void append_nv(Request *req, char **nv)
{
  for(int i = 0; nv[i]; i += 2) {
    req->headers.push_back(std::make_pair(nv[i], nv[i+1]));
  }
}
} // namespace

namespace {
void hd_on_ctrl_recv_callback
(spdylay_session *session, spdylay_frame_type type, spdylay_frame *frame,
 void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  if(config.verbose) {
    print_session_id(hd->session_id());
    on_ctrl_recv_callback(session, type, frame, user_data);
  }
  switch(type) {
  case SPDYLAY_SYN_STREAM: {
    int32_t stream_id = frame->syn_stream.stream_id;
    Request *req = new Request(stream_id);
    append_nv(req, frame->syn_stream.nv);
    hd->add_stream(stream_id, req);
    break;
  }
  case SPDYLAY_HEADERS: {
    int32_t stream_id = frame->headers.stream_id;
    Request *req = hd->get_stream(stream_id);
    append_nv(req, frame->headers.nv);
    break;
  }
  default:
    break;
  }
}
} // namespace

namespace {
void hd_on_request_recv_callback
(spdylay_session *session, int32_t stream_id, void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  prepare_response(hd->get_stream(stream_id), hd);
}
} // namespace

namespace {
void hd_on_ctrl_send_callback
(spdylay_session *session, spdylay_frame_type type, spdylay_frame *frame,
 void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  if(config.verbose) {
    print_session_id(hd->session_id());
    on_ctrl_send_callback(session, type, frame, user_data);
  }
}
} // namespace

namespace {
void on_data_chunk_recv_callback
(spdylay_session *session, uint8_t flags, int32_t stream_id,
 const uint8_t *data, size_t len, void *user_data)
{
  // TODO Handle POST
}
} // namespace

namespace {
void hd_on_data_recv_callback
(spdylay_session *session, uint8_t flags, int32_t stream_id, int32_t length,
 void *user_data)
{
  // TODO Handle POST
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  if(config.verbose) {
    print_session_id(hd->session_id());
    on_data_recv_callback(session, flags, stream_id, length, user_data);
  }
}
} // namespace

namespace {
void hd_on_data_send_callback
(spdylay_session *session, uint8_t flags, int32_t stream_id, int32_t length,
 void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  if(config.verbose) {
    print_session_id(hd->session_id());
    on_data_send_callback(session, flags, stream_id, length, user_data);
  }
}
} // namespace

namespace {
void on_stream_close_callback
(spdylay_session *session, int32_t stream_id, spdylay_status_code status_code,
 void *user_data)
{
  SpdyEventHandler *hd = (SpdyEventHandler*)user_data;
  hd->remove_stream(stream_id);
  if(config.verbose) {
    print_session_id(hd->session_id());
    print_timer();
    printf(" stream_id=%d closed\n", stream_id);
    fflush(stdout);
  }
}
} // namespace

class SSLAcceptEventHandler : public EventHandler {
public:
  SSLAcceptEventHandler(int fd, SSL *ssl, int64_t session_id)
    : fd_(fd), ssl_(ssl), fail_(false),
      want_read_(true), want_write_(true), finish_(false),
      session_id_(session_id)
  {}
  virtual ~SSLAcceptEventHandler()
  {
    if(fail_) {
      on_session_closed(session_id_);
      SSL_shutdown(ssl_);
      SSL_free(ssl_);
      shutdown(fd_, SHUT_WR);
      close(fd_);
    }
  }
  virtual int execute(Sessions *sessions)
  {
    want_read_ = want_write_ = false;
    int r = SSL_accept(ssl_);
    if(r == 1) {
      finish_ = true;
      const unsigned char *next_proto = 0;
      unsigned int next_proto_len;
      SSL_get0_next_proto_negotiated(ssl_, &next_proto, &next_proto_len);
      if(next_proto) {
        std::string proto(next_proto, next_proto+next_proto_len);
        if(config.verbose) {
          std::cout << "The negotiated next protocol: " << proto << std::endl;
        }
        if(proto == "spdy/2") {
          add_next_handler(sessions);
        } else {
          fail_ = true;
        }
      } else {
        fail_ = true;
      }
    } else if(r == 0) {
      int e = SSL_get_error(ssl_, r);
      if(e == SSL_ERROR_SSL) {
        if(config.verbose) {
          std::cerr << ERR_error_string(ERR_get_error(), 0) << std::endl;
        }
      }
      finish_ = true;
      fail_ = true;
    } else {
      int d = SSL_get_error(ssl_, r);
      if(d == SSL_ERROR_WANT_READ) {
        want_read_ = true;
      } else if(d == SSL_ERROR_WANT_WRITE) {
        want_write_ = true;
      } else {
        finish_ = true;
        fail_ = true;
      }
    }
    return 0;
  }
  virtual bool want_read()
  {
    return want_read_;
  }
  virtual bool want_write()
  {
    return want_write_;
  }
  virtual int fd() const
  {
    return fd_;
  }
  virtual bool finish()
  {
    return finish_;
  }
private:
  void add_next_handler(Sessions *sessions)
  {
    spdylay_session_callbacks callbacks;
    memset(&callbacks, 0, sizeof(spdylay_session_callbacks));
    callbacks.send_callback = hd_send_callback;
    callbacks.recv_callback = hd_recv_callback;
    callbacks.on_stream_close_callback = on_stream_close_callback;
    callbacks.on_ctrl_recv_callback = hd_on_ctrl_recv_callback;
    callbacks.on_ctrl_send_callback = hd_on_ctrl_send_callback;
    callbacks.on_data_recv_callback = hd_on_data_recv_callback;
    callbacks.on_data_send_callback = hd_on_data_send_callback;
    callbacks.on_data_chunk_recv_callback = on_data_chunk_recv_callback;
    callbacks.on_request_recv_callback = hd_on_request_recv_callback;
    SpdyEventHandler *hd = new SpdyEventHandler(fd_, ssl_, &callbacks,
                                                session_id_);
    if(sessions->mod_poll(hd) == -1) {
      // fd_, ssl_ are freed by ~SpdyEventHandler()
      delete hd;
    } else {
      sessions->add_handler(hd);
    }
  }
  
  int fd_;
  SSL *ssl_;
  bool fail_, finish_;
  bool want_read_, want_write_;
  int64_t session_id_;
};

class ListenEventHandler : public EventHandler {
public:
  ListenEventHandler(int fd) : fd_(fd), session_id_seed_(0) {}
  virtual ~ListenEventHandler()
  {
    close(fd_);
  }
  virtual int execute(Sessions *sessions)
  {
    int cfd;
    while((cfd = accept(fd_, 0, 0)) == -1 && errno == EINTR);
    if(cfd != -1) {
      if(make_non_block(cfd) == -1 ||
         set_tcp_nodelay(cfd) == -1) {
        close(cfd);
      } else {
        add_next_handler(sessions, cfd);
      }
    }
    return 0;
  }
  virtual bool want_read()
  {
    return true;
  }
  virtual bool want_write()
  {
    return false;
  }
  virtual int fd() const
  {
    return fd_;
  }
  virtual bool finish()
  {
    return false;
  }
private:
  void add_next_handler(Sessions *sessions, int cfd)
  {
    SSL *ssl = sessions->ssl_session_new(cfd);
    if(ssl == 0) {
      close(cfd);
      return;
    }
    SSLAcceptEventHandler *hd = new SSLAcceptEventHandler(cfd, ssl,
                                                          ++session_id_seed_);
    if(sessions->add_poll(hd) == -1) {
      delete hd;
      SSL_free(ssl);
      close(cfd);
    } else {
      sessions->add_handler(hd);
    }
  }

  int fd_;
  int64_t session_id_seed_;
};

namespace {
void on_close(Sessions &sessions, EventHandler *hd)
{
  sessions.remove_handler(hd);
  delete hd;
}
} // namespace

namespace {
unsigned char *proto_list;
unsigned int proto_list_len;
} // namespace

namespace {
int next_proto_cb(SSL *s, const unsigned char **data, unsigned int *len,
                  void *arg)
{
  *data = proto_list;
  *len = proto_list_len;
  return SSL_TLSEXT_ERR_OK;
}
} // namespace

namespace {
int reactor()
{
  SSL_CTX *ssl_ctx;
  ssl_ctx = SSL_CTX_new(SSLv23_server_method());
  if(!ssl_ctx) {
    std::cerr << ERR_error_string(ERR_get_error(), 0) << std::endl;
    return -1;
  }
  SSL_CTX_set_options(ssl_ctx, SSL_OP_ALL|SSL_OP_NO_SSLv2);
  SSL_CTX_set_mode(ssl_ctx, SSL_MODE_AUTO_RETRY);
  SSL_CTX_set_mode(ssl_ctx, SSL_MODE_RELEASE_BUFFERS);
  if(SSL_CTX_use_PrivateKey_file(ssl_ctx,
                                 config.private_key_file.c_str(),
                                 SSL_FILETYPE_PEM) != 1) {
    std::cerr << "SSL_CTX_use_PrivateKey_file failed." << std::endl;
    return -1;
  }
  if(SSL_CTX_use_certificate_file(ssl_ctx, config.cert_file.c_str(),
                                  SSL_FILETYPE_PEM) != 1) {
    std::cerr << "SSL_CTX_use_certificate_file failed." << std::endl;
    return -1;
  }
  if(SSL_CTX_check_private_key(ssl_ctx) != 1) {
    std::cerr << "SSL_CTX_check_private_key failed." << std::endl;
    return -1;
  }
  SSL_CTX_set_next_protos_advertised_cb(ssl_ctx, next_proto_cb, 0);

  const size_t MAX_EVENTS = 256;
  Sessions sessions(MAX_EVENTS, ssl_ctx);

  int families[] = { AF_INET, AF_INET6 };
  bool bind_ok = false;
  for(int i = 0; i < 2; ++i) {
    const char* ipv = (families[i] == AF_INET ? "IPv4" : "IPv6");
    int sfd = make_listen_socket(config.port, families[i]);
    if(sfd == -1) {
      std::cerr << ipv << ": Could not listen on port " << config.port
                << std::endl;
    }
    make_non_block(sfd);

    ListenEventHandler *listen_hd = new ListenEventHandler(sfd);
    if(sessions.add_poll(listen_hd) == -1) {
      std::cerr <<  ipv << ": Adding listening socket to poll failed."
                << std::endl;
      delete listen_hd;
    }
    sessions.add_handler(listen_hd);
    if(config.verbose) {
      std::cout << ipv << ": listen on port " << config.port << std::endl;
    }
    bind_ok = true;
  }
  if(!bind_ok) {
    return -1;
  }

  std::vector<EventHandler*> del_list;
  while(1) {
    int n = sessions.poll(-1);
    if(n == -1) {
      perror("EventPoll");
    } else {
      for(int i = 0; i < n; ++i) {
        EventHandler *hd = reinterpret_cast<EventHandler*>
          (sessions.get_user_data(i));
        int events = sessions.get_events(i);
        int r = 0;
        if(hd->mark_del()) {
          continue;
        }
        if((events & EP_POLLIN) || (events & EP_POLLOUT)) {
          r = hd->execute(&sessions);
        } else if(events & (EP_POLLERR | EP_POLLHUP)) {
          hd->mark_del(true);
        }
        if(r != 0) {
          hd->mark_del(true);
        } else {
          if(hd->finish()) {
            hd->mark_del(true);
          } else {
            sessions.mod_poll(hd);
          }
        }
      }
      for(std::vector<EventHandler*>::iterator i = del_list.begin(),
            eoi = del_list.end(); i != eoi; ++i) {
        on_close(sessions, *i);
      }
      del_list.clear();
    }
  }
  return 0;
}
} // namespace

namespace {
void print_usage(std::ostream& out)
{
  out << "Usage: spdyd [-Ddhv] PORT PRIVATE_KEY CERT" << std::endl;
}
} // namespace

namespace {
void print_help(std::ostream& out)
{
  print_usage(out);
  out << "\n"
      << "OPTIONS:\n"
      << "    -D, --daemon       Run in a background. If -D is used, the\n"
      << "                       current working directory is changed to '/'.\n"
      << "                       Therefore if this option is used, -d option\n"
      << "                       must be specified.\n"
      << "\n"
      << "    -d, --htdocs=PATH  Specify document root. If this option is not\n"
      << "                       specified, the document root is the current\n"
      << "                       working directory.\n"
      << "\n"
      << "    -v, --verbose      Print debug information such as reception/\n"
      << "                       transmission of frames and name/value pairs.\n"
      << "\n"
      << "    -h, --help         Print this help.\n"
      << std::endl;
}
} // namespace

int main(int argc, char **argv)
{
  while(1) {
    static option long_options[] = {
      {"daemon", no_argument, 0, 'D' },
      {"htdocs", required_argument, 0, 'd' },
      {"help", no_argument, 0, 'h' },
      {"verbose", no_argument, 0, 'v' },
      {0, 0, 0, 0 }
    };
    int option_index = 0;
    int c = getopt_long(argc, argv, "Dd:hv", long_options, &option_index);
    if(c == -1) {
      break;
    }
    switch(c) {
    case 'D':
      config.daemon = true;
      break;
    case 'd':
      config.htdocs = optarg;
      break;
    case 'h':
      print_help(std::cout);
      exit(EXIT_SUCCESS);
    case 'v':
      config.verbose = true;
      break;
    case '?':
      exit(EXIT_FAILURE);
    default:
      break;
    }
  }
  if(argc-optind < 3) {
    print_usage(std::cerr);
    std::cerr << "Too few arguments" << std::endl;
    exit(EXIT_FAILURE);
  }
  if(config.daemon) {
    if(config.htdocs.empty()) {
      print_usage(std::cerr);
      std::cerr << "-d option must be specified when -D is used." << std::endl;
      exit(EXIT_FAILURE);
    }
    if(daemon(0, 0) == -1) {
      perror("daemon");
      exit(EXIT_FAILURE);
    }
  }
  if(config.htdocs.empty()) {
    config.htdocs = "./";
  }
  struct sigaction act;
  memset(&act, 0, sizeof(struct sigaction));
  act.sa_handler = SIG_IGN;
  sigaction(SIGPIPE, &act, 0);
  OpenSSL_add_all_algorithms();
  SSL_load_error_strings();
  SSL_library_init();
  reset_timer();
  config.port = strtol(argv[optind++], 0, 10);
  config.private_key_file = argv[optind++];
  config.cert_file = argv[optind++];
  ssl_debug = config.verbose;
  // We only speak "spdy/2".
  proto_list_len = 7;
  proto_list = new unsigned char[proto_list_len];
  proto_list[0] = 6;
  memcpy(&proto_list[1], "spdy/2", 6);
  reactor();
  delete [] proto_list;
  return 0;
}

} // namespace spdylay

int main(int argc, char **argv)
{
  return spdylay::main(argc, argv);
}