diff options
Diffstat (limited to 'mysys/queues.c')
| -rw-r--r-- | mysys/queues.c | 45 |
1 files changed, 38 insertions, 7 deletions
diff --git a/mysys/queues.c b/mysys/queues.c index f077b38ca0b..ecf1058af41 100644 --- a/mysys/queues.c +++ b/mysys/queues.c @@ -64,7 +64,7 @@ int init_queue(QUEUE *queue, uint max_elements, uint offset_to_key, /* - Reinitialize queue for other usage (deletes all elements) + Reinitialize queue for other usage SYNOPSIS reinit_queue() @@ -77,8 +77,8 @@ int init_queue(QUEUE *queue, uint max_elements, uint offset_to_key, first_cmp_arg First argument to compare function NOTES - You can't currently resize the number of elements! If you need this, - fix it :) + This will delete all elements from the queue. If you don't want this, + use resize_queue() instead. RETURN 0 ok @@ -90,15 +90,46 @@ int reinit_queue(QUEUE *queue, uint max_elements, uint offset_to_key, void *first_cmp_arg) { DBUG_ENTER("reinit_queue"); - if (queue->max_elements < max_elements) - /* It's real easy to do realloc here, just don't want to bother */ - DBUG_RETURN(my_errno=EE_OUTOFMEMORY); - queue->elements=0; queue->compare=compare; queue->first_cmp_arg=first_cmp_arg; queue->offset_to_key=offset_to_key; queue->max_at_top= max_at_top ? (-1 ^ 1) : 0; + resize_queue(queue, max_elements); + DBUG_RETURN(0); +} + + +/* + Resize queue + + SYNOPSIS + resize_queue() + queue Queue + max_elements New max size for queue + + NOTES + If you resize queue to be less than the elements you have in it, + the extra elements will be deleted + + RETURN + 0 ok + 1 Error. In this case the queue is unchanged +*/ + +int resize_queue(QUEUE *queue, uint max_elements) +{ + byte **new_root; + DBUG_ENTER("resize_queue"); + if (queue->max_elements == max_elements) + DBUG_RETURN(0); + if ((new_root= (byte **) my_realloc((void *)queue->root, + (max_elements+1)*sizeof(void*), + MYF(MY_WME))) == 0) + DBUG_RETURN(1); + set_if_smaller(queue->elements, max_elements); + queue->max_elements= max_elements; + queue->root= new_root; DBUG_RETURN(0); } |