static CURLcode easy_transfer(CURLM *multi)
{
  bool done = FALSE;
  CURLMcode mcode = CURLM_OK;
  CURLcode code = CURLE_OK;
  struct timeval before;
  int without_fds = 0;  /* count number of consecutive returns from
                           curl_multi_wait() without any filedescriptors */

  while(!done && !mcode) {
    int still_running;
    int ret;

    before = curlx_tvnow();
    mcode = curl_multi_wait(multi, NULL, 0, 1000, &ret);

    if(mcode == CURLM_OK) {
      if(ret == -1) {
        /* poll() failed not on EINTR, indicate a network problem */
        code = CURLE_RECV_ERROR;
        break;
      }
      else if(ret == 0) {
        struct timeval after = curlx_tvnow();
        /* If it returns without any filedescriptor instantly, we need to
           avoid busy-looping during periods where it has nothing particular
           to wait for */
        if(curlx_tvdiff(after, before) <= 10) {
          without_fds++;
          if(without_fds > 2) {
            int sleep_ms = without_fds < 10 ? (1 << (without_fds-1)): 1000;
            Curl_wait_ms(sleep_ms);
          }
        }
        else
          /* it wasn't "instant", restart counter */
          without_fds = 0;
      }
      else
        /* got file descriptor, restart counter */
        without_fds = 0;

      mcode = curl_multi_perform(multi, &still_running);
    }

    /* only read 'still_running' if curl_multi_perform() return OK */
    if((mcode == CURLM_OK) && !still_running) {
      int rc;
      CURLMsg *msg = curl_multi_info_read(multi, &rc);
      if(msg) {
        code = msg->data.result;
        done = TRUE;
      }
    }
  }
  return code;
}

/*
 * Portable function used for waiting a specific amount of ms.
 * Waiting indefinitely with this function is not allowed, a
 * zero or negative timeout value will return immediately.
 *
 * Return values:
 *   -1 = system call error, or invalid timeout value
 *    0 = specified timeout has elapsed
 */
int wait_ms(int timeout_ms)
{
#if !defined(MSDOS) && !defined(USE_WINSOCK)
#ifndef HAVE_POLL_FINE
  struct timeval pending_tv;
#endif
  struct timeval initial_tv;
  int pending_ms;
  int error;
#endif
  int r = 0;

  if(!timeout_ms)
    return 0;
  if(timeout_ms < 0) {
    SET_SOCKERRNO(EINVAL);
    return -1;
  }
#if defined(MSDOS)
  delay(timeout_ms);
#elif defined(USE_WINSOCK)
  Sleep(timeout_ms);
#else
  pending_ms = timeout_ms;
  initial_tv = curlx_tvnow();
  do {
#if defined(HAVE_POLL_FINE)
    r = poll(NULL, 0, pending_ms);
#else
    pending_tv.tv_sec = pending_ms / 1000;
    pending_tv.tv_usec = (pending_ms % 1000) * 1000;
    r = select(0, NULL, NULL, NULL, &pending_tv);
#endif /* HAVE_POLL_FINE */
    if(r != -1)
      break;
    error = SOCKERRNO;
    if(error && (error != EINTR))
      break;
    pending_ms = timeout_ms - (int)curlx_tvdiff(curlx_tvnow(), initial_tv);
    if(pending_ms <= 0)
      break;
  } while(r == -1);
#endif /* USE_WINSOCK */
  if(r)
    r = -1;
  return r;
}

/*
 * Internal function used for waiting a specific amount of ms
 * in Curl_socket_check() and Curl_poll() when no file descriptor
 * is provided to wait on, just being used to delay execution.
 * WinSock select() and poll() timeout mechanisms need a valid
 * socket descriptor in a not null file descriptor set to work.
 * Waiting indefinitely with this function is not allowed, a
 * zero or negative timeout value will return immediately.
 * Timeout resolution, accuracy, as well as maximum supported
 * value is system dependent, neither factor is a citical issue
 * for the intended use of this function in the library.
 *
 * Return values:
 *   -1 = system call error, invalid timeout value, or interrupted
 *    0 = specified timeout has elapsed
 */
int Curl_wait_ms(int timeout_ms)
{
#if !defined(MSDOS) && !defined(USE_WINSOCK)
#ifndef HAVE_POLL_FINE
  struct timeval pending_tv;
#endif
  struct timeval initial_tv;
  int pending_ms;
  int error;
#endif
  int r = 0;

  if(!timeout_ms)
    return 0;
  if(timeout_ms < 0) {
    SET_SOCKERRNO(EINVAL);
    return -1;
  }
#if defined(MSDOS)
  delay(timeout_ms);
#elif defined(USE_WINSOCK)
  Sleep(timeout_ms);
#else
  pending_ms = timeout_ms;
  initial_tv = curlx_tvnow();
  do {
#if defined(HAVE_POLL_FINE)
    r = poll(NULL, 0, pending_ms);
#else
    pending_tv.tv_sec = pending_ms / 1000;
    pending_tv.tv_usec = (pending_ms % 1000) * 1000;
    r = select(0, NULL, NULL, NULL, &pending_tv);
#endif /* HAVE_POLL_FINE */
    if(r != -1)
      break;
    error = SOCKERRNO;
    if(error && ERROR_NOT_EINTR(error))
      break;
    pending_ms = timeout_ms - ELAPSED_MS();
    if(pending_ms <= 0) {
      r = 0;  /* Simulate a "call timed out" case */
      break;
    }
  } while(r == -1);
#endif /* USE_WINSOCK */
  if(r)
    r = -1;
  return r;
}

void logmsg(const char *msg, ...)
{
  va_list ap;
  char buffer[2048 + 1];
  FILE *logfp;
  int error;
  struct timeval tv;
  time_t sec;
  struct tm *now;
  char timebuf[20];
  static time_t epoch_offset;
  static int    known_offset;

  if (!serverlogfile) {
    fprintf(stderr, "Error: serverlogfile not set\n");
    return;
  }

  tv = curlx_tvnow();
  if(!known_offset) {
    epoch_offset = time(NULL) - tv.tv_sec;
    known_offset = 1;
  }
  sec = epoch_offset + tv.tv_sec;
  now = localtime(&sec); /* not thread safe but we don't care */

  snprintf(timebuf, sizeof(timebuf), "%02d:%02d:%02d.%06ld",
    (int)now->tm_hour, (int)now->tm_min, (int)now->tm_sec, (long)tv.tv_usec);

  va_start(ap, msg);
  vsnprintf(buffer, sizeof(buffer), msg, ap);
  va_end(ap);

  logfp = fopen(serverlogfile, "ab");
  if(logfp) {
    fprintf(logfp, "%s %s\n", timebuf, buffer);
    fclose(logfp);
  }
  else {
    error = ERRNO;
    fprintf(stderr, "fopen() failed with error: %d %s\n",
            error, strerror(error));
    fprintf(stderr, "Error opening file: %s\n", serverlogfile);
    fprintf(stderr, "Msg not logged: %s %s\n", timebuf, buffer);
  }
}

void logmsg(const char *msg, ...)
{
  va_list ap;
  char buffer[256]; /* possible overflow if you pass in a huge string */
  FILE *logfp;

  struct timeval tv = curlx_tvnow();
  struct tm *now =
    localtime(&tv.tv_sec); /* not multithread safe but we don't care */

  char timebuf[20];
  snprintf(timebuf, sizeof(timebuf), "%02d:%02d:%02d.%06ld",
           now->tm_hour, now->tm_min, now->tm_sec, tv.tv_usec);

  va_start(ap, msg);
  vsprintf(buffer, msg, ap);
  va_end(ap);

  logfp = fopen(serverlogfile, "a");
  if(logfp) {
    fprintf(logfp, "%s %s\n", timebuf, buffer);
    fclose(logfp);
  }
}

static CURLcode easy_transfer(struct Curl_multi *multi)
{
  bool done = FALSE;
  CURLMcode mcode = CURLM_OK;
  CURLcode result = CURLE_OK;
  struct timeval before;
  int without_fds = 0;  /* count number of consecutive returns from
                           curl_multi_wait() without any filedescriptors */

  while(!done && !mcode) {
    int still_running = 0;
    int rc;

    before = curlx_tvnow();
    mcode = curl_multi_wait(multi, NULL, 0, 1000, &rc);

    if(!mcode) {
      if(!rc) {
        struct timeval after = curlx_tvnow();

        /* If it returns without any filedescriptor instantly, we need to
           avoid busy-looping during periods where it has nothing particular
           to wait for */
        if(curlx_tvdiff(after, before) <= 10) {
          without_fds++;
          if(without_fds > 2) {
            int sleep_ms = without_fds < 10 ? (1 << (without_fds - 1)) : 1000;
            Curl_wait_ms(sleep_ms);
          }
        }
        else
          /* it wasn't "instant", restart counter */
          without_fds = 0;
      }
      else
        /* got file descriptor, restart counter */
        without_fds = 0;

      mcode = curl_multi_perform(multi, &still_running);
    }

    /* only read 'still_running' if curl_multi_perform() return OK */
    if(!mcode && !still_running) {
      CURLMsg *msg = curl_multi_info_read(multi, &rc);
      if(msg) {
        result = msg->data.result;
        done = TRUE;
      }
    }
  }

  /* Make sure to return some kind of error if there was a multi problem */
  if(mcode) {
    result = (mcode == CURLM_OUT_OF_MEMORY) ? CURLE_OUT_OF_MEMORY :
              /* The other multi errors should never happen, so return
                 something suitably generic */
              CURLE_BAD_FUNCTION_ARGUMENT;
  }

  return result;
}

static CURLcode wait_or_timeout(struct Curl_multi *multi, struct events *ev)
{
  bool done = FALSE;
  CURLMcode mcode;
  CURLcode result = CURLE_OK;

  while(!done) {
    CURLMsg *msg;
    struct socketmonitor *m;
    struct pollfd *f;
    struct pollfd fds[4];
    int numfds=0;
    int pollrc;
    int i;
    struct timeval before;
    struct timeval after;

    /* populate the fds[] array */
    for(m = ev->list, f=&fds[0]; m; m = m->next) {
      f->fd = m->socket.fd;
      f->events = m->socket.events;
      f->revents = 0;
      /* fprintf(stderr, "poll() %d check socket %d\n", numfds, f->fd); */
      f++;
      numfds++;
    }

    /* get the time stamp to use to figure out how long poll takes */
    before = curlx_tvnow();

    /* wait for activity or timeout */
    pollrc = Curl_poll(fds, numfds, (int)ev->ms);

    after = curlx_tvnow();

    ev->msbump = FALSE; /* reset here */

    if(0 == pollrc) {
      /* timeout! */
      ev->ms = 0;
      /* fprintf(stderr, "call curl_multi_socket_action(TIMEOUT)\n"); */
      mcode = curl_multi_socket_action(multi, CURL_SOCKET_TIMEOUT, 0,
                                       &ev->running_handles);
    }
    else if(pollrc > 0) {
      /* loop over the monitored sockets to see which ones had activity */
      for(i = 0; i< numfds; i++) {
        if(fds[i].revents) {
          /* socket activity, tell libcurl */
          int act = poll2cselect(fds[i].revents); /* convert */
          infof(multi->easyp, "call curl_multi_socket_action(socket %d)\n",
                fds[i].fd);
          mcode = curl_multi_socket_action(multi, fds[i].fd, act,
                                           &ev->running_handles);
        }
      }

      if(!ev->msbump)
        /* If nothing updated the timeout, we decrease it by the spent time.
         * If it was updated, it has the new timeout time stored already.
         */
        ev->ms += curlx_tvdiff(after, before);

    }
    else
      return CURLE_RECV_ERROR;

    if(mcode)
      return CURLE_URL_MALFORMAT; /* TODO: return a proper error! */

    /* we don't really care about the "msgs_in_queue" value returned in the
       second argument */
    msg = curl_multi_info_read(multi, &pollrc);
    if(msg) {
      result = msg->data.result;
      done = TRUE;
    }
  }

  return result;
}

/*
 * This is a wrapper around poll().  If poll() does not exist, then
 * select() is used instead.  An error is returned if select() is
 * being used and a file descriptor is too large for FD_SETSIZE.
 * A negative timeout value makes this function wait indefinitely,
 * unles no valid file descriptor is given, when this happens the
 * negative timeout is ignored and the function times out immediately.
 *
 * Return values:
 *   -1 = system call error or fd >= FD_SETSIZE
 *    0 = timeout
 *    N = number of structures with non zero revent fields
 */
int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
{
#ifndef HAVE_POLL_FINE
  struct timeval pending_tv;
  struct timeval *ptimeout;
  fd_set fds_read;
  fd_set fds_write;
  fd_set fds_err;
  curl_socket_t maxfd;
#endif
  struct timeval initial_tv = {0,0};
  bool fds_none = TRUE;
  unsigned int i;
  int pending_ms = 0;
  int error;
  int r;

  if(ufds) {
    for(i = 0; i < nfds; i++) {
      if(ufds[i].fd != CURL_SOCKET_BAD) {
        fds_none = FALSE;
        break;
      }
    }
  }
  if(fds_none) {
    r = Curl_wait_ms(timeout_ms);
    return r;
  }

  /* Avoid initial timestamp, avoid curlx_tvnow() call, when elapsed
     time in this function does not need to be measured. This happens
     when function is called with a zero timeout or a negative timeout
     value indicating a blocking call should be performed. */

  if(timeout_ms > 0) {
    pending_ms = timeout_ms;
    initial_tv = curlx_tvnow();
  }

#ifdef HAVE_POLL_FINE

  do {
    if(timeout_ms < 0)
      pending_ms = -1;
    else if(!timeout_ms)
      pending_ms = 0;
    r = poll(ufds, nfds, pending_ms);
    if(r != -1)
      break;
    error = SOCKERRNO;
    if(error && error_not_EINTR)
      break;
    if(timeout_ms > 0) {
      pending_ms = timeout_ms - elapsed_ms;
      if(pending_ms <= 0)
        break;
    }
  } while(r == -1);

  if(r < 0)
    return -1;
  if(r == 0)
    return 0;

  for(i = 0; i < nfds; i++) {
    if(ufds[i].fd == CURL_SOCKET_BAD)
      continue;
    if(ufds[i].revents & POLLHUP)
      ufds[i].revents |= POLLIN;
    if(ufds[i].revents & POLLERR)
      ufds[i].revents |= (POLLIN|POLLOUT);
  }

#else  /* HAVE_POLL_FINE */

  FD_ZERO(&fds_read);
  FD_ZERO(&fds_write);
  FD_ZERO(&fds_err);
  maxfd = (curl_socket_t)-1;

  for(i = 0; i < nfds; i++) {
    ufds[i].revents = 0;
    if(ufds[i].fd == CURL_SOCKET_BAD)
      continue;
    VERIFY_SOCK(ufds[i].fd);
    if(ufds[i].events & (POLLIN|POLLOUT|POLLPRI|
//.........这里部分代码省略.........

/*
 * Wait for read or write events on a set of file descriptors. It uses poll()
 * when a fine poll() is available, in order to avoid limits with FD_SETSIZE,
 * otherwise select() is used.  An error is returned if select() is being used
 * and a file descriptor is too large for FD_SETSIZE.
 *
 * A negative timeout value makes this function wait indefinitely,
 * unles no valid file descriptor is given, when this happens the
 * negative timeout is ignored and the function times out immediately.
 *
 * Return values:
 *   -1 = system call error or fd >= FD_SETSIZE
 *    0 = timeout
 *    [bitmask] = action as described below
 *
 * CURL_CSELECT_IN - first socket is readable
 * CURL_CSELECT_IN2 - second socket is readable
 * CURL_CSELECT_OUT - write socket is writable
 * CURL_CSELECT_ERR - an error condition occurred
 */
int Curl_socket_check(curl_socket_t readfd0, /* two sockets to read from */
                      curl_socket_t readfd1,
                      curl_socket_t writefd, /* socket to write to */
                      long timeout_ms)       /* milliseconds to wait */
{
#ifdef HAVE_POLL_FINE
  struct pollfd pfd[3];
  int num;
#else
  struct timeval pending_tv;
  struct timeval *ptimeout;
  fd_set fds_read;
  fd_set fds_write;
  fd_set fds_err;
  curl_socket_t maxfd;
#endif
  struct timeval initial_tv = {0,0};
  int pending_ms = 0;
  int error;
  int r;
  int ret;

  if((readfd0 == CURL_SOCKET_BAD) && (readfd1 == CURL_SOCKET_BAD) &&
     (writefd == CURL_SOCKET_BAD)) {
    /* no sockets, just wait */
    r = Curl_wait_ms((int)timeout_ms);
    return r;
  }

  /* Avoid initial timestamp, avoid curlx_tvnow() call, when elapsed
     time in this function does not need to be measured. This happens
     when function is called with a zero timeout or a negative timeout
     value indicating a blocking call should be performed. */

  if(timeout_ms > 0) {
    pending_ms = (int)timeout_ms;
    initial_tv = curlx_tvnow();
  }

#ifdef HAVE_POLL_FINE

  num = 0;
  if(readfd0 != CURL_SOCKET_BAD) {
    pfd[num].fd = readfd0;
    pfd[num].events = POLLRDNORM|POLLIN|POLLRDBAND|POLLPRI;
    pfd[num].revents = 0;
    num++;
  }
  if(readfd1 != CURL_SOCKET_BAD) {
    pfd[num].fd = readfd1;
    pfd[num].events = POLLRDNORM|POLLIN|POLLRDBAND|POLLPRI;
    pfd[num].revents = 0;
    num++;
  }
  if(writefd != CURL_SOCKET_BAD) {
    pfd[num].fd = writefd;
    pfd[num].events = POLLWRNORM|POLLOUT;
    pfd[num].revents = 0;
    num++;
  }

  do {
    if(timeout_ms < 0)
      pending_ms = -1;
    else if(!timeout_ms)
      pending_ms = 0;
    r = poll(pfd, num, pending_ms);
    if(r != -1)
      break;
    error = SOCKERRNO;
    if(error && error_not_EINTR)
      break;
    if(timeout_ms > 0) {
      pending_ms = (int)(timeout_ms - elapsed_ms);
      if(pending_ms <= 0) {
        r = 0;  /* Simulate a "call timed out" case */
        break;
      }
    }
  } while(r == -1);
//.........这里部分代码省略.........

/*
 * This is an internal function used for waiting for read or write
 * events on a pair of file descriptors.  It uses poll() when a fine
 * poll() is available, in order to avoid limits with FD_SETSIZE,
 * otherwise select() is used.  An error is returned if select() is
 * being used and a file descriptor is too large for FD_SETSIZE.
 * A negative timeout value makes this function wait indefinitely,
 * unles no valid file descriptor is given, when this happens the
 * negative timeout is ignored and the function times out immediately.
 * When compiled with CURL_ACKNOWLEDGE_EINTR defined, EINTR condition
 * is honored and function might exit early without awaiting timeout,
 * otherwise EINTR will be ignored.
 *
 * Return values:
 *   -1 = system call error or fd >= FD_SETSIZE
 *    0 = timeout
 *    CURL_CSELECT_IN | CURL_CSELECT_OUT | CURL_CSELECT_ERR
 */
int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
                      int timeout_ms)
{
#ifdef HAVE_POLL_FINE
  struct pollfd pfd[2];
  int num;
#else
  struct timeval pending_tv;
  struct timeval *ptimeout;
  fd_set fds_read;
  fd_set fds_write;
  fd_set fds_err;
  curl_socket_t maxfd;
#endif
  struct timeval initial_tv = {0,0};
  int pending_ms = 0;
  int error;
  int r;
  int ret;

  if((readfd == CURL_SOCKET_BAD) && (writefd == CURL_SOCKET_BAD)) {
    r = wait_ms(timeout_ms);
    return r;
  }

  /* Avoid initial timestamp, avoid curlx_tvnow() call, when elapsed
     time in this function does not need to be measured. This happens
     when function is called with a zero timeout or a negative timeout
     value indicating a blocking call should be performed. */

  if(timeout_ms > 0) {
    pending_ms = timeout_ms;
    initial_tv = curlx_tvnow();
  }

#ifdef HAVE_POLL_FINE

  num = 0;
  if(readfd != CURL_SOCKET_BAD) {
    pfd[num].fd = readfd;
    pfd[num].events = POLLRDNORM|POLLIN|POLLRDBAND|POLLPRI;
    pfd[num].revents = 0;
    num++;
  }
  if(writefd != CURL_SOCKET_BAD) {
    pfd[num].fd = writefd;
    pfd[num].events = POLLWRNORM|POLLOUT;
    pfd[num].revents = 0;
    num++;
  }

  do {
    if(timeout_ms < 0)
      pending_ms = -1;
    else if(!timeout_ms)
      pending_ms = 0;
    r = poll(pfd, num, pending_ms);
    if(r != -1)
      break;
    error = SOCKERRNO;
    if(error && error_not_EINTR)
      break;
    if(timeout_ms > 0) {
      pending_ms = timeout_ms - elapsed_ms;
      if(pending_ms <= 0)
        break;
    }
  } while(r == -1);

  if(r < 0)
    return -1;
  if(r == 0)
    return 0;

  ret = 0;
  num = 0;
  if(readfd != CURL_SOCKET_BAD) {
    if(pfd[num].revents & (POLLRDNORM|POLLIN|POLLERR|POLLHUP))
      ret |= CURL_CSELECT_IN;
    if(pfd[num].revents & (POLLRDBAND|POLLPRI|POLLNVAL))
      ret |= CURL_CSELECT_ERR;
    num++;
//.........这里部分代码省略.........

/*
 * This is a wrapper around poll().  If poll() does not exist, then
 * select() is used instead.  An error is returned if select() is
 * being used and a file descriptor is too large for FD_SETSIZE.
 * A negative timeout value makes this function wait indefinitely,
 * unles no valid file descriptor is given, when this happens the
 * negative timeout is ignored and the function times out immediately.
 * When compiled with CURL_ACKNOWLEDGE_EINTR defined, EINTR condition
 * is honored and function might exit early without awaiting timeout,
 * otherwise EINTR will be ignored.
 *
 * Return values:
 *   -1 = system call error or fd >= FD_SETSIZE
 *    0 = timeout
 *    N = number of structures with non zero revent fields
 */
int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
{
#ifndef HAVE_POLL_FINE
  struct timeval pending_tv;
  struct timeval *ptimeout;
  fd_set fds_read;
  fd_set fds_write;
  fd_set fds_err;
  curl_socket_t maxfd;
#endif
  struct timeval initial_tv;
  bool fds_none = TRUE;
  unsigned int i;
  int pending_ms;
  int error;
  int r;

  if (ufds) {
    for (i = 0; i < nfds; i++) {
      if (ufds[i].fd != CURL_SOCKET_BAD) {
        fds_none = FALSE;
        break;
      }
    }
  }
  if (fds_none) {
    r = wait_ms(timeout_ms);
    return r;
  }

  pending_ms = timeout_ms;
  initial_tv = curlx_tvnow();

#ifdef HAVE_POLL_FINE

  do {
    if (timeout_ms < 0)
      pending_ms = -1;
    r = poll(ufds, nfds, pending_ms);
  } while ((r == -1) && (error = SOCKERRNO) &&
           (error != EINVAL) && error_not_EINTR &&
           ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));

#else  /* HAVE_POLL_FINE */

  FD_ZERO(&fds_read);
  FD_ZERO(&fds_write);
  FD_ZERO(&fds_err);
  maxfd = (curl_socket_t)-1;

  for (i = 0; i < nfds; i++) {
    ufds[i].revents = 0;
    if (ufds[i].fd == CURL_SOCKET_BAD)
      continue;
    VERIFY_SOCK(ufds[i].fd);
    if (ufds[i].events & (POLLIN|POLLOUT|POLLPRI|
                          POLLRDNORM|POLLWRNORM|POLLRDBAND)) {
      if (ufds[i].fd > maxfd)
        maxfd = ufds[i].fd;
      if (ufds[i].events & (POLLRDNORM|POLLIN))
        FD_SET(ufds[i].fd, &fds_read);
      if (ufds[i].events & (POLLWRNORM|POLLOUT))
        FD_SET(ufds[i].fd, &fds_write);
      if (ufds[i].events & (POLLRDBAND|POLLPRI))
        FD_SET(ufds[i].fd, &fds_err);
    }
  }

  ptimeout = (timeout_ms < 0) ? NULL : &pending_tv;

  do {
    if (ptimeout) {
      pending_tv.tv_sec = pending_ms / 1000;
      pending_tv.tv_usec = (pending_ms % 1000) * 1000;
    }
    r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
  } while ((r == -1) && (error = SOCKERRNO) &&
           (error != EINVAL) && (error != EBADF) && error_not_EINTR &&
           ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));

  if (r < 0)
    return -1;
  if (r == 0)
    return 0;
//.........这里部分代码省略.........

int test(char *URL)
{
  int res = 0;
  CURL *curl[NUM_HANDLES];
  int running;
  char done=FALSE;
  CURLM *m;
  int current=0;
  int i, j;
  struct timeval ml_start;
  struct timeval mp_start;
  char ml_timedout = FALSE;
  char mp_timedout = FALSE;

  if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    fprintf(stderr, "curl_global_init() failed\n");
    return TEST_ERR_MAJOR_BAD;
  }

  /* get NUM_HANDLES easy handles */
  for(i=0; i < NUM_HANDLES; i++) {
    curl[i] = curl_easy_init();
    if(!curl[i]) {
      fprintf(stderr, "curl_easy_init() failed "
              "on handle #%d\n", i);
      for (j=i-1; j >= 0; j--) {
        curl_easy_cleanup(curl[j]);
      }
      curl_global_cleanup();
      return TEST_ERR_MAJOR_BAD + i;
    }
    curl_easy_setopt(curl[i], CURLOPT_URL, URL);

    /* go verbose */
    curl_easy_setopt(curl[i], CURLOPT_VERBOSE, 1);
  }

  if ((m = curl_multi_init()) == NULL) {
    fprintf(stderr, "curl_multi_init() failed\n");
    for(i=0; i < NUM_HANDLES; i++) {
      curl_easy_cleanup(curl[i]);
    }
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  if ((res = (int)curl_multi_add_handle(m, curl[current])) != CURLM_OK) {
    fprintf(stderr, "curl_multi_add_handle() failed, "
            "with code %d\n", res);
    curl_multi_cleanup(m);
    for(i=0; i < NUM_HANDLES; i++) {
      curl_easy_cleanup(curl[i]);
    }
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  ml_timedout = FALSE;
  ml_start = curlx_tvnow();

  fprintf(stderr, "Start at URL 0\n");

  while (!done) {
    fd_set rd, wr, exc;
    int max_fd;
    struct timeval interval;

    interval.tv_sec = 1;
    interval.tv_usec = 0;

    if (curlx_tvdiff(curlx_tvnow(), ml_start) > 
        MAIN_LOOP_HANG_TIMEOUT) {
      ml_timedout = TRUE;
      break;
    }
    mp_timedout = FALSE;
    mp_start = curlx_tvnow();

    while (res == CURLM_CALL_MULTI_PERFORM) {
      res = (int)curl_multi_perform(m, &running);
      if (curlx_tvdiff(curlx_tvnow(), mp_start) > 
          MULTI_PERFORM_HANG_TIMEOUT) {
        mp_timedout = TRUE;
        break;
      }
      if (running <= 0) {
#ifdef LIB527
        /* NOTE: this code does not remove the handle from the multi handle
           here, which would be the nice, sane and documented way of working.
           This however tests that the API survives this abuse gracefully. */
        curl_easy_cleanup(curl[current]);
#endif
        if(++current < NUM_HANDLES) {
          fprintf(stderr, "Advancing to URL %d\n", current);
#ifdef LIB532
          /* first remove the only handle we use */
          curl_multi_remove_handle(m, curl[0]);

          /* make us re-use the same handle all the time, and try resetting
             the handle first too */
//.........这里部分代码省略.........

/*
 * This is a wrapper around poll().  If poll() does not exist, then
 * select() is used instead.  An error is returned if select() is
 * being used and a file descriptor is too large for FD_SETSIZE.
 * A negative timeout value makes this function wait indefinitely,
 * unles no valid file descriptor is given, when this happens the
 * negative timeout is ignored and the function times out immediately.
 * When compiled with CURL_ACKNOWLEDGE_EINTR defined, EINTR condition
 * is honored and function might exit early without awaiting timeout,
 * otherwise EINTR will be ignored.
 *
 * Return values:
 *   -1 = system call error or fd >= FD_SETSIZE
 *    0 = timeout
 *    N = number of structures with non zero revent fields
 */
int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
{
#ifndef HAVE_POLL_FINE
    struct timeval pending_tv;
    struct timeval *ptimeout;
    fd_set fds_read;
    fd_set fds_write;
    fd_set fds_err;
    curl_socket_t maxfd;
#endif
    struct timeval initial_tv;
    bool fds_none = TRUE;
    unsigned int i;
    int pending_ms = 0;
    int error;
    int r;

    if (ufds) {
        for (i = 0; i < nfds; i++) {
            if (ufds[i].fd != CURL_SOCKET_BAD) {
                fds_none = FALSE;
                break;
            }
        }
    }
    if (fds_none) {
        r = wait_ms(timeout_ms);
        return r;
    }

    /* Avoid initial timestamp, avoid gettimeofday() call, when elapsed
       time in this function does not need to be measured. This happens
       when function is called with a zero timeout or a negative timeout
       value indicating a blocking call should be performed. */

    if (timeout_ms > 0) {
        pending_ms = timeout_ms;
        initial_tv = curlx_tvnow();
    }

#ifdef HAVE_POLL_FINE

    do {
        if (timeout_ms < 0)
            pending_ms = -1;
        else if (!timeout_ms)
            pending_ms = 0;
        r = poll(ufds, nfds, pending_ms);
        if (r != -1)
            break;
        error = SOCKERRNO;
        if ((error == EINVAL) || error_is_EINTR)
            break;
        if (timeout_ms > 0) {
            pending_ms = timeout_ms - elapsed_ms;
            if (pending_ms <= 0)
                break;
        }
    } while (r == -1);

#else  /* HAVE_POLL_FINE */

    FD_ZERO(&fds_read);
    FD_ZERO(&fds_write);
    FD_ZERO(&fds_err);
    maxfd = (curl_socket_t)-1;

    for (i = 0; i < nfds; i++) {
        ufds[i].revents = 0;
        if (ufds[i].fd == CURL_SOCKET_BAD)
            continue;
        VERIFY_SOCK(ufds[i].fd);
        if (ufds[i].events & (POLLIN|POLLOUT|POLLPRI|
                              POLLRDNORM|POLLWRNORM|POLLRDBAND)) {
            if (ufds[i].fd > maxfd)
                maxfd = ufds[i].fd;
            if (ufds[i].events & (POLLRDNORM|POLLIN))
                FD_SET(ufds[i].fd, &fds_read);
            if (ufds[i].events & (POLLWRNORM|POLLOUT))
                FD_SET(ufds[i].fd, &fds_write);
            if (ufds[i].events & (POLLRDBAND|POLLPRI))
                FD_SET(ufds[i].fd, &fds_err);
        }
    }
//.........这里部分代码省略.........

int test(char *URL)
{
  CURLM* multi;
  sslctxparm p;
  CURLMcode res;
  int running;
  char done = FALSE;
  int i = 0;
  CURLMsg *msg;

  struct timeval ml_start;
  struct timeval mp_start;
  char ml_timedout = FALSE;
  char mp_timedout = FALSE;

  if(arg2) {
    portnum = atoi(arg2);
  }

  if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    fprintf(stderr, "curl_global_init() failed\n");
    return TEST_ERR_MAJOR_BAD;
  }

  if ((p.curl = curl_easy_init()) == NULL) {
    fprintf(stderr, "curl_easy_init() failed\n");
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  p.accessinfoURL = (unsigned char *) strdup(URL);
  p.accesstype = OBJ_obj2nid(OBJ_txt2obj("AD_DVCS",0)) ;

  curl_easy_setopt(p.curl, CURLOPT_URL, p.accessinfoURL);

  curl_easy_setopt(p.curl, CURLOPT_SSL_CTX_FUNCTION, sslctxfun)  ;
  curl_easy_setopt(p.curl, CURLOPT_SSL_CTX_DATA, &p);

  curl_easy_setopt(p.curl, CURLOPT_SSL_VERIFYPEER, FALSE);
  curl_easy_setopt(p.curl, CURLOPT_SSL_VERIFYHOST, 1);

  if ((multi = curl_multi_init()) == NULL) {
    fprintf(stderr, "curl_multi_init() failed\n");
    curl_easy_cleanup(p.curl);
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  if ((res = curl_multi_add_handle(multi, p.curl)) != CURLM_OK) {
    fprintf(stderr, "curl_multi_add_handle() failed, "
            "with code %d\n", res);
    curl_multi_cleanup(multi);
    curl_easy_cleanup(p.curl);
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  fprintf(stderr, "Going to perform %s\n", (char *)p.accessinfoURL);

  ml_timedout = FALSE;
  ml_start = curlx_tvnow();

  while (!done) {
    fd_set rd, wr, exc;
    int max_fd;
    struct timeval interval;

    interval.tv_sec = 1;
    interval.tv_usec = 0;

    if (curlx_tvdiff(curlx_tvnow(), ml_start) > 
        MAIN_LOOP_HANG_TIMEOUT) {
      ml_timedout = TRUE;
      break;
    }
    mp_timedout = FALSE;
    mp_start = curlx_tvnow();

    while (res == CURLM_CALL_MULTI_PERFORM) {
      res = curl_multi_perform(multi, &running);
      if (curlx_tvdiff(curlx_tvnow(), mp_start) > 
          MULTI_PERFORM_HANG_TIMEOUT) {
        mp_timedout = TRUE;
        break;
      }
      fprintf(stderr, "running=%d res=%d\n",running,res);
      if (running <= 0) {
        done = TRUE;
        break;
      }
    }
    if (mp_timedout || done)
      break;

    if (res != CURLM_OK) {
      fprintf(stderr, "not okay???\n");
      i = 80;
      break;
    }

//.........这里部分代码省略.........

/*
 * curl_easy_perform() is the external interface that performs a blocking
 * transfer as previously setup.
 *
 * CONCEPT: This function creates a multi handle, adds the easy handle to it,
 * runs curl_multi_perform() until the transfer is done, then detaches the
 * easy handle, destroys the multi handle and returns the easy handle's return
 * code.
 *
 * REALITY: it can't just create and destroy the multi handle that easily. It
 * needs to keep it around since if this easy handle is used again by this
 * function, the same multi handle must be re-used so that the same pools and
 * caches can be used.
 */
CURLcode curl_easy_perform(CURL *easy)
{
  CURLM *multi;
  CURLMcode mcode;
  CURLcode code = CURLE_OK;
  CURLMsg *msg;
  bool done = FALSE;
  int rc;
  struct SessionHandle *data = easy;
  int without_fds = 0;  /* count number of consecutive returns from
                           curl_multi_wait() without any filedescriptors */
  struct timeval before;

  if(!easy)
    return CURLE_BAD_FUNCTION_ARGUMENT;

  if(data->multi) {
    failf(data, "easy handled already used in multi handle");
    return CURLE_FAILED_INIT;
  }

  if(data->multi_easy)
    multi = data->multi_easy;
  else {
    /* this multi handle will only ever have a single easy handled attached
       to it, so make it use minimal hashes */
    multi = Curl_multi_handle(1, 3);
    if(!multi)
      return CURLE_OUT_OF_MEMORY;
    data->multi_easy = multi;
  }

  /* Copy the MAXCONNECTS option to the multi handle */
  curl_multi_setopt(multi, CURLMOPT_MAXCONNECTS, data->set.maxconnects);

  mcode = curl_multi_add_handle(multi, easy);
  if(mcode) {
    curl_multi_cleanup(multi);
    if(mcode == CURLM_OUT_OF_MEMORY)
      return CURLE_OUT_OF_MEMORY;
    else
      return CURLE_FAILED_INIT;
  }

  /* assign this after curl_multi_add_handle() since that function checks for
     it and rejects this handle otherwise */
  data->multi = multi;

  while(!done && !mcode) {
    int still_running;
    int ret;

    before = curlx_tvnow();
    mcode = curl_multi_wait(multi, NULL, 0, 1000, &ret);

    if(mcode == CURLM_OK) {
      if(ret == -1) {
        /* poll() failed not on EINTR, indicate a network problem */
        code = CURLE_RECV_ERROR;
        break;
      }
      else if(ret == 0) {
        struct timeval after = curlx_tvnow();
        /* If it returns without any filedescriptor instantly, we need to
           avoid busy-looping during periods where it has nothing particular
           to wait for */
        if(curlx_tvdiff(after, before) <= 10) {
          without_fds++;
          if(without_fds > 2) {
            int sleep_ms = without_fds * 50;
            if(sleep_ms > 1000)
              sleep_ms = 1000;
            Curl_wait_ms(sleep_ms);
          }
        }
        else
          /* it wasn't "instant", restart counter */
          without_fds = 0;
      }
      else
        /* got file descriptor, restart counter */
        without_fds = 0;

      mcode = curl_multi_perform(multi, &still_running);
    }

//.........这里部分代码省略.........

/*
 * This is a wrapper around select().  It uses poll() when a fine
 * poll() is available, in order to avoid limits with FD_SETSIZE,
 * otherwise select() is used.  An error is returned if select() is
 * being used and a the number of file descriptors is larger than
 * FD_SETSIZE.  A NULL timeout pointer makes this function wait
 * indefinitely, unles no valid file descriptor is given, when this
 * happens the NULL timeout is ignored and the function times out
 * immediately.  When compiled with CURL_ACKNOWLEDGE_EINTR defined,
 * EINTR condition is honored and function might exit early without
 * awaiting timeout, otherwise EINTR will be ignored.
 *
 * Return values:
 *   -1 = system call error or nfds > FD_SETSIZE
 *    0 = timeout
 *    N = number of file descriptors kept in file descriptor sets.
 */
int Curl_select(int nfds,
                fd_set *fds_read, fd_set *fds_write, fd_set *fds_excep,
                struct timeval *timeout)
{
  struct timeval initial_tv;
  int timeout_ms;
  int pending_ms;
  int error;
  int r;
#ifdef HAVE_POLL_FINE
  struct pollfd small_fds[SMALL_POLLNFDS];
  struct pollfd *poll_fds;
  int ix;
  int fd;
  int poll_nfds = 0;
#else
  struct timeval pending_tv;
  struct timeval *ptimeout;
#endif
  int ret = 0;

  if ((nfds < 0) ||
     ((nfds > 0) && (!fds_read && !fds_write && !fds_excep))) {
    SET_SOCKERRNO(EINVAL);
    return -1;
  }

  if (timeout) {
    if ((timeout->tv_sec < 0) ||
        (timeout->tv_usec < 0) ||
        (timeout->tv_usec >= 1000000)) {
      SET_SOCKERRNO(EINVAL);
      return -1;
    }
    timeout_ms = (int)(timeout->tv_sec * 1000) + (int)(timeout->tv_usec / 1000);
  }
  else {
    timeout_ms = -1;
  }

  if ((!nfds) || (!fds_read && !fds_write && !fds_excep)) {
    r = wait_ms(timeout_ms);
    return r;
  }

  pending_ms = timeout_ms;
  initial_tv = curlx_tvnow();

#ifdef HAVE_POLL_FINE

  if (fds_read || fds_write || fds_excep) {
    fd = nfds;
    while (fd--) {
      if ((fds_read && (0 != FD_ISSET(fd, fds_read))) ||
          (fds_write && (0 != FD_ISSET(fd, fds_write))) ||
          (fds_excep && (0 != FD_ISSET(fd, fds_excep))))
        poll_nfds++;
    }
  }

  if (!poll_nfds)
    poll_fds = NULL;
  else if (poll_nfds <= SMALL_POLLNFDS)
    poll_fds = small_fds;
  else {
    poll_fds = calloc((size_t)poll_nfds, sizeof(struct pollfd));
    if (!poll_fds) {
      SET_SOCKERRNO(ENOBUFS);
      return -1;
    }
  }

  if (poll_fds) {
    ix = 0;
    fd = nfds;
    while (fd--) {
      poll_fds[ix].events = 0;
      if (fds_read && (0 != FD_ISSET(fd, fds_read)))
        poll_fds[ix].events |= (POLLRDNORM|POLLIN);
      if (fds_write && (0 != FD_ISSET(fd, fds_write)))
        poll_fds[ix].events |= (POLLWRNORM|POLLOUT);
      if (fds_excep && (0 != FD_ISSET(fd, fds_excep)))
        poll_fds[ix].events |= (POLLRDBAND|POLLPRI);
//.........这里部分代码省略.........

/*
 * Source code in here hugely as reported in bug report 651464 by
 * Christopher R. Palmer.
 *
 * Use multi interface to get document over proxy with bad port number.
 * This caused the interface to "hang" in libcurl 7.10.2.
 */
int test(char *URL)
{
  CURL *c;
  int ret=0;
  CURLM *m;
  fd_set rd, wr, exc;
  CURLMcode res;
  char done = FALSE;
  int running;
  int max_fd;
  int rc;
  struct timeval ml_start;
  struct timeval mp_start;
  char ml_timedout = FALSE;
  char mp_timedout = FALSE;

  if (curl_global_init(CURL_GLOBAL_ALL) != CURLE_OK) {
    fprintf(stderr, "curl_global_init() failed\n");
    return TEST_ERR_MAJOR_BAD;
  }

  if ((c = curl_easy_init()) == NULL) {
    fprintf(stderr, "curl_easy_init() failed\n");
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  /* the point here being that there must not run anything on the given
     proxy port */
  curl_easy_setopt(c, CURLOPT_PROXY, arg2);
  curl_easy_setopt(c, CURLOPT_URL, URL);
  curl_easy_setopt(c, CURLOPT_VERBOSE, 1);

  if ((m = curl_multi_init()) == NULL) {
    fprintf(stderr, "curl_multi_init() failed\n");
    curl_easy_cleanup(c);
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  if ((res = curl_multi_add_handle(m, c)) != CURLM_OK) {
    fprintf(stderr, "curl_multi_add_handle() failed, "
            "with code %d\n", res);
    curl_multi_cleanup(m);
    curl_easy_cleanup(c);
    curl_global_cleanup();
    return TEST_ERR_MAJOR_BAD;
  }

  ml_timedout = FALSE;
  ml_start = curlx_tvnow();

  while (!done) {
    struct timeval interval;

    interval.tv_sec = 1;
    interval.tv_usec = 0;

    if (curlx_tvdiff(curlx_tvnow(), ml_start) > 
        MAIN_LOOP_HANG_TIMEOUT) {
      ml_timedout = TRUE;
      break;
    }
    mp_timedout = FALSE;
    mp_start = curlx_tvnow();

    fprintf(stderr, "curl_multi_perform()\n");

    res = CURLM_CALL_MULTI_PERFORM;

    while (res == CURLM_CALL_MULTI_PERFORM) {
      res = curl_multi_perform(m, &running);
      if (curlx_tvdiff(curlx_tvnow(), mp_start) > 
          MULTI_PERFORM_HANG_TIMEOUT) {
        mp_timedout = TRUE;
        break;
      }
    }
    if (mp_timedout)
      break;

    if(!running) {
      /* This is where this code is expected to reach */
      int numleft;
      CURLMsg *msg = curl_multi_info_read(m, &numleft);
      fprintf(stderr, "Expected: not running\n");
      if(msg && !numleft)
        ret = 100; /* this is where we should be */
      else
        ret = 99; /* not correct */
      break;
    }
    fprintf(stderr, "running == %d, res == %d\n", running, res);
//.........这里部分代码省略.........