Commit 280d2cff authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

multi: avoid sending multiple complete messages 

I fell over this bug report that mentioned that libcurl could wrongly
send more than one complete messages at the end of a transfer. Reading
the code confirmed this, so I've added a new multi state to make it not
happen. The mentioned bug report was made by Brad Jorsch but is (oddly
enough) filed in Debian's bug tracker for the "wmweather+" tool.

Bug: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=593390
parent ac20f52e

lib/multi.c

+12 −5
Original line number Diff line number Diff line
@@ -83,7 +83,7 @@ typedef enum { 
  CURLM_STATE_TOOFAST,     /* wait because limit-rate exceeded */

  CURLM_STATE_DONE,        /* post data transfer operation */

  CURLM_STATE_COMPLETED,   /* operation complete */



  CURLM_STATE_MSGSENT,     /* the operation complete message is sent */

  CURLM_STATE_LAST /* not a true state, never use this */

} CURLMstate;
@@ -211,6 +211,7 @@ static const char * const statename[]={ 
  "TOOFAST",

  "DONE",

  "COMPLETED",

  "MSGSENT",

};

#endif
@@ -622,7 +623,7 @@ CURLMcode curl_multi_remove_handle(CURLM *multi_handle, 
  easy = data->multi_pos;



  if(easy) {

    bool premature = (bool)(easy->state != CURLM_STATE_COMPLETED);

    bool premature = (bool)(easy->state < CURLM_STATE_COMPLETED);

    bool easy_owns_conn = (bool)(easy->easy_conn &&

                                 (easy->easy_conn->data == easy->easy_handle));
@@ -837,6 +838,7 @@ static int multi_getsock(struct Curl_one_easy *easy, 
         to be present */

  case CURLM_STATE_TOOFAST:  /* returns 0, so will not select. */

  case CURLM_STATE_COMPLETED:

  case CURLM_STATE_MSGSENT:

  case CURLM_STATE_INIT:

  case CURLM_STATE_CONNECT:

  case CURLM_STATE_WAITDO:
@@ -952,7 +954,7 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi, 
      infof(data, "Pipe broke: handle 0x%p, url = %s\n",

            easy, data->state.path);



      if(easy->state != CURLM_STATE_COMPLETED) {

      if(easy->state < CURLM_STATE_COMPLETED) {

        /* Head back to the CONNECT state */

        multistate(easy, CURLM_STATE_CONNECT);

        result = CURLM_CALL_MULTI_PERFORM;
@@ -1563,11 +1565,14 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi, 
      easy->easy_conn = NULL;

      break;



    case CURLM_STATE_MSGSENT:

      return CURLM_OK; /* do nothing */



    default:

      return CURLM_INTERNAL_ERROR;

    }



    if(CURLM_STATE_COMPLETED != easy->state) {

    if(CURLM_STATE_COMPLETED > easy->state) {

      if(CURLE_OK != easy->result) {

        /*

         * If an error was returned, and we aren't in completed state now,
@@ -1625,6 +1630,8 @@ static CURLMcode multi_runsingle(struct Curl_multi *multi, 
    msg->extmsg.data.result = easy->result;



    result = multi_addmsg(multi, msg);



    multistate(easy, CURLM_STATE_MSGSENT);

  }



  return result;
@@ -2686,7 +2693,7 @@ void Curl_multi_dump(const struct Curl_multi *multi_handle) 
  fprintf(stderr, "* Multi status: %d handles, %d alive\n",

          multi->num_easy, multi->num_alive);

  for(easy=multi->easy.next; easy != &multi->easy; easy = easy->next) {

    if(easy->state != CURLM_STATE_COMPLETED) {

    if(easy->state < CURLM_STATE_COMPLETED) {

      /* only display handles that are not completed */

      fprintf(stderr, "handle %p, state %s, %d sockets\n",

              (void *)easy->easy_handle,