indexer: Don't send more requests directly from worker status callback

This causes assert-crashes when workers disconnect while having multiple
requests:

indexer: Error: Indexer worker disconnected, discarding 2 requests for user@domain
indexer: Panic: file indexer.c: line 69 (queue_try_send_more): assertion failed: (worker_connection_is_connected(conn))

diff --git a/src/indexer/indexer.c b/src/indexer/indexer.c
index 89b7fb611c3a93c51ca6b419df13c08941a71ed9..a30c16d4b11d8e3cc89b21d1f4dfc6e903577ef7 100644 (file)
--- a/src/indexer/indexer.c
+++ b/src/indexer/indexer.c
@@ -1,6 +1,7 @@
 /* Copyright (c) 2011-2017 Dovecot authors, see the included COPYING file */
 
 #include "lib.h"
+#include "ioloop.h"
 #include "restrict-access.h"
 #include "process-title.h"
 #include "master-service.h"
@@ -18,6 +19,7 @@ struct worker_request {
 static const struct master_service_settings *set;
 static struct indexer_queue *queue;
 static struct worker_pool *worker_pool;
+static struct timeout *to_send_more;
 
 void indexer_refresh_proctitle(void)
 {
@@ -59,6 +61,9 @@ static void queue_try_send_more(struct indexer_queue *queue)
        struct worker_connection *conn;
        struct indexer_request *request;
 
+       if (to_send_more != NULL)
+               timeout_remove(&to_send_more);
+
        while ((request = indexer_queue_request_peek(queue)) != NULL) {
                conn = worker_pool_find_username_connection(worker_pool,
                                                            request->username);
@@ -98,8 +103,10 @@ static void worker_status_callback(int percentage, void *context)
        i_free(request);
 
        /* if this was the last request for the connection, we can send more
-          through it */
-       queue_try_send_more(queue);
+          through it. delay it a bit, since we may be coming here from
+          worker_connection_disconnect() and we want to finish it up. */
+       if (to_send_more == NULL)
+               to_send_more = timeout_add_short(0, queue_try_send_more, queue);
 }
 
 int main(int argc, char *argv[])
@@ -132,6 +139,8 @@ int main(int argc, char *argv[])
        indexer_clients_destroy_all();
        worker_pool_deinit(&worker_pool);
        indexer_queue_deinit(&queue);
+       if (to_send_more != NULL)
+               timeout_remove(&to_send_more);
 
        master_service_deinit(&master_service);
         return 0;