Commit 0db91407 authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

multi: make sure the next timeout is used when one expires 

Each easy handle has a list of timeouts, so as soon as the main timeout
for a handle expires, we must make sure to get the next entry from the
list and re-add the handle to the splay tree.

This was attempted previously but was done poorly in my commit
232ad654.
parent 55c266de

lib/multi.c

+64 −40
Original line number Diff line number Diff line
@@ -192,6 +192,9 @@ static void moveHandleFromRecvToDonePipeline(struct SessionHandle *handle, 
                                             struct connectdata *conn);

static bool isHandleAtHead(struct SessionHandle *handle,

                           struct curl_llist *pipeline);

static CURLMcode add_next_timeout(struct timeval now,

                                  struct Curl_multi *multi,

                                  struct SessionHandle *d);



#ifdef DEBUGBUILD

static const char * const statename[]={
@@ -1690,37 +1693,9 @@ CURLMcode curl_multi_perform(CURLM *multi_handle, int *running_handles) 
   */

  do {

    multi->timetree = Curl_splaygetbest(now, multi->timetree, &t);

    if(t) {

      struct SessionHandle *d = t->payload;

      struct timeval *tv = &d->state.expiretime;

      struct curl_llist *list = d->state.timeoutlist;

      struct curl_llist_element *e;



      /* move over the timeout list for this specific handle and remove all

         timeouts that are now passed tense and store the next pending

         timeout in *tv */

      for(e = list->head; e; ) {

        struct curl_llist_element *n = e->next;

        if(curlx_tvdiff(*(struct timeval *)e->ptr, now) < 0)

          /* remove outdated entry */

          Curl_llist_remove(list, e, NULL);

        e = n;

      }

      if(!list->size)  {

        /* clear the expire times within the handles that we remove from the

           splay tree */

        tv->tv_sec = 0;

        tv->tv_usec = 0;

      }

      else {

        e = list->head;

        /* copy the first entry to 'tv' */

        memcpy(tv, e->ptr, sizeof(*tv));



        /* remove first entry from list */

        Curl_llist_remove(list, e, NULL);

      }

    }

    if(t)

      /* the removed may have another timeout in queue */

      (void)add_next_timeout(now, multi, t->payload);



  } while(t);
@@ -1992,6 +1967,62 @@ static void singlesocket(struct Curl_multi *multi, 
  easy->numsocks = num;

}



/*

 * add_next_timeout()

 *

 * Each SessionHandle has a list of timeouts. The add_next_timeout() is called

 * when it has just been removed from the splay tree because the timeout has

 * expired. This function is then to advance in the list to pick the next

 * timeout to use (skip the already expired ones) and add this node back to

 * the splay tree again.

 *

 * The splay tree only has each sessionhandle as a single node and the nearest

 * timeout is used to sort it on.

 */

static CURLMcode add_next_timeout(struct timeval now,

                                  struct Curl_multi *multi,

                                  struct SessionHandle *d)

{

  struct timeval *tv = &d->state.expiretime;

  struct curl_llist *list = d->state.timeoutlist;

  struct curl_llist_element *e;



  /* move over the timeout list for this specific handle and remove all

     timeouts that are now passed tense and store the next pending

     timeout in *tv */

  for(e = list->head; e; ) {

    struct curl_llist_element *n = e->next;

    long diff = curlx_tvdiff(*(struct timeval *)e->ptr, now);

    if(diff <= 0)

      /* remove outdated entry */

      Curl_llist_remove(list, e, NULL);

    else

      /* the list is sorted so get out on the first mismatch */

      break;

    e = n;

  }

  if(!list->size)  {

    /* clear the expire times within the handles that we remove from the

       splay tree */

    tv->tv_sec = 0;

    tv->tv_usec = 0;

  }

  else {

    e = list->head;

    /* copy the first entry to 'tv' */

    memcpy(tv, e->ptr, sizeof(*tv));



    /* remove first entry from list */

    Curl_llist_remove(list, e, NULL);



    /* insert this node again into the splay */

    multi->timetree = Curl_splayinsert(*tv, multi->timetree,

                                       &d->state.timenode);

  }

  return CURLM_OK;

}





static CURLMcode multi_socket(struct Curl_multi *multi,

                              bool checkall,

                              curl_socket_t s,
@@ -2106,15 +2137,8 @@ static CURLMcode multi_socket(struct Curl_multi *multi, 
    }



    multi->timetree = Curl_splaygetbest(now, multi->timetree, &t);

    if(t) {

      /* assign 'data' to be the easy handle we just removed from the splay

         tree */

      data = t->payload;

      /* clear the expire time within the handle we removed from the

         splay tree */

      data->state.expiretime.tv_sec = 0;

      data->state.expiretime.tv_usec = 0;

    }

    if(t)

      (void)add_next_timeout(now, multi, t->payload);



  } while(t);