Unverified Commit fb445a1e authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

disconnect: separate connections and easy handles better 

Do not assume/store assocation between a given easy handle and the
connection if it can be avoided.

Long-term, the 'conn->data' pointer should probably be removed as it is a
little too error-prone. Still used very widely though.

Reported-by: masbug on github
Fixes #3391
Closes #3400
parent d18a5afa

lib/conncache.c

+8 −2
Original line number Diff line number Diff line
@@ -302,9 +302,14 @@ CURLcode Curl_conncache_add_conn(struct conncache *connc, 
  return result;

}



void Curl_conncache_remove_conn(struct connectdata *conn, bool lock)

/*

 * Removes the connectdata object from the connection cache *and* clears the

 * ->data pointer association. Pass TRUE/FALSE in the 'lock' argument

 * depending on if the parent function already holds the lock or not.

 */

void Curl_conncache_remove_conn(struct Curl_easy *data,

                                struct connectdata *conn, bool lock)

{

  struct Curl_easy *data = conn->data;

  struct connectbundle *bundle = conn->bundle;

  struct conncache *connc = data->state.conn_cache;
@@ -323,6 +328,7 @@ void Curl_conncache_remove_conn(struct connectdata *conn, bool lock) 
      DEBUGF(infof(data, "The cache now contains %zu members\n",

                   connc->num_conn));

    }

    conn->data = NULL; /* clear the association */

    if(lock) {

      CONN_UNLOCK(data);

    }

lib/conncache.h

+2 −1
Original line number Diff line number Diff line
@@ -64,7 +64,8 @@ size_t Curl_conncache_bundle_size(struct connectdata *conn); 
bool Curl_conncache_return_conn(struct connectdata *conn);

CURLcode Curl_conncache_add_conn(struct conncache *connc,

                                 struct connectdata *conn) WARN_UNUSED_RESULT;

void Curl_conncache_remove_conn(struct connectdata *conn,

void Curl_conncache_remove_conn(struct Curl_easy *data,

                                struct connectdata *conn,

                                bool lock);

bool Curl_conncache_foreach(struct Curl_easy *data,

                            struct conncache *connc,

lib/multi.c

+1 −3
Original line number Diff line number Diff line
@@ -761,10 +761,8 @@ CURLMcode curl_multi_remove_handle(struct Curl_multi *multi, 
                                vanish with this handle */



  /* Remove the association between the connection and the handle */

  if(data->easy_conn) {

    data->easy_conn->data = NULL;

  if(data->easy_conn)

    data->easy_conn = NULL;

  }



#ifdef USE_LIBPSL

  /* Remove the PSL association. */

lib/url.c

+2 −7
Original line number Diff line number Diff line
@@ -769,7 +769,6 @@ CURLcode Curl_disconnect(struct Curl_easy *data, 
    return CURLE_OK;

  }



  conn->data = data;

  if(conn->dns_entry != NULL) {

    Curl_resolv_unlock(data, conn->dns_entry);

    conn->dns_entry = NULL;
@@ -788,14 +787,13 @@ CURLcode Curl_disconnect(struct Curl_easy *data, 


    /* unlink ourselves! */

  infof(data, "Closing connection %ld\n", conn->connection_id);

  Curl_conncache_remove_conn(conn, TRUE);

  Curl_conncache_remove_conn(data, conn, TRUE);



  free_idnconverted_hostname(&conn->host);

  free_idnconverted_hostname(&conn->conn_to_host);

  free_idnconverted_hostname(&conn->http_proxy.host);

  free_idnconverted_hostname(&conn->socks_proxy.host);



  DEBUGASSERT(conn->data == data);

  /* this assumes that the pointer is still there after the connection was

     detected from the cache */

  Curl_ssl_close(conn, FIRSTSOCKET);
@@ -960,8 +958,6 @@ static bool extract_if_dead(struct connectdata *conn, 
       handles in pipeline and the connection isn't already marked in

       use */

    bool dead;



    conn->data = data;

    if(conn->handler->connection_check) {

      /* The protocol has a special method for checking the state of the

         connection. Use it to check if the connection is dead. */
@@ -977,8 +973,7 @@ static bool extract_if_dead(struct connectdata *conn, 


    if(dead) {

      infof(data, "Connection %ld seems to be dead!\n", conn->connection_id);

      Curl_conncache_remove_conn(conn, FALSE);

      conn->data = NULL; /* detach */

      Curl_conncache_remove_conn(data, conn, FALSE);

      return TRUE;

    }

  }