mariadb/include/queues.h
unknown 81eadfcac1 WL#1034 update
QUEUE implementation working now. this should be ready more or less
for testing once the debug output is being cleaned and some things
around DYNAMIC_ARRAY are cleaned
- fix handling in case of errors that lead to crashes, now no more crashes
  in case of table corruption and such.


include/queues.h:
  introduce a safe version of queue_insert that will extend the queue if
  necessary. the auto_extent is passed to the _ex version of init_queue()
mysys/queues.c:
  add init_queue_ex() implementation
  add queue_insert_safe() implementation
sql/event.cc:
  - move mysql_priv.h inclusion to event_priv.h
  - use a priority queue instead of DYNAMIC_ARRAY which is sorted
sql/event.h:
  reorder
sql/event_executor.cc:
  reorder
sql/event_priv.h:
  - reorder a bit
  - add macroses and functions for queue manipulation which stay on top
   of QUEUE (partly implemented for DYNAMIC_ARRAY but will be cleared to be
   only for QUEUE).
sql/event_timed.cc:
  allocate one more byte and zeroterminate, really
2005-12-12 21:19:19 +01:00

73 lines
2.6 KiB
C

/* Copyright (C) 2000 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/*
Code for generell handling of priority Queues.
Implemention of queues from "Algoritms in C" by Robert Sedgewick.
Copyright Monty Program KB.
By monty.
*/
#ifndef _queues_h
#define _queues_h
#ifdef __cplusplus
extern "C" {
#endif
typedef struct st_queue {
byte **root;
void *first_cmp_arg;
uint elements;
uint max_elements;
uint offset_to_key; /* compare is done on element+offset */
int max_at_top; /* Set if queue_top gives max */
int (*compare)(void *, byte *,byte *);
uint auto_extent;
} QUEUE;
#define queue_top(queue) ((queue)->root[1])
#define queue_element(queue,index) ((queue)->root[index+1])
#define queue_end(queue) ((queue)->root[(queue)->elements])
#define queue_replaced(queue) _downheap(queue,1)
#define queue_set_cmp_arg(queue, set_arg) (queue)->first_cmp_arg= set_arg
#define queue_set_max_at_top(queue, set_arg) \
(queue)->max_at_top= set_arg ? (-1 ^ 1) : 0
typedef int (*queue_compare)(void *,byte *, byte *);
int init_queue(QUEUE *queue,uint max_elements,uint offset_to_key,
pbool max_at_top, queue_compare compare,
void *first_cmp_arg);
int init_queue_ex(QUEUE *queue,uint max_elements,uint offset_to_key,
pbool max_at_top, queue_compare compare,
void *first_cmp_arg, uint auto_extent);
int reinit_queue(QUEUE *queue,uint max_elements,uint offset_to_key,
pbool max_at_top, queue_compare compare,
void *first_cmp_arg);
int resize_queue(QUEUE *queue, uint max_elements);
void delete_queue(QUEUE *queue);
void queue_insert(QUEUE *queue,byte *element);
int queue_insert_safe(QUEUE *queue, byte *element);
byte *queue_remove(QUEUE *queue,uint idx);
#define queue_remove_all(queue) { (queue)->elements= 0; }
#define queue_is_full(queue) (queue->elements == queue->max_elements)
void _downheap(QUEUE *queue,uint idx);
void queue_fix(QUEUE *queue);
#define is_queue_inited(queue) ((queue)->root != 0)
#ifdef __cplusplus
}
#endif
#endif