/*
* Copyright (c) 2007, Novell Inc.
*
* This program is licensed under the BSD license, read LICENSE.BSD
* for further information
*/
/*
* queue.h
*
*/
#ifndef LIBSOLV_QUEUE_H
#define LIBSOLV_QUEUE_H
#include "pooltypes.h"
#ifdef __cplusplus
extern "C" {
#endif
typedef struct s_Queue {
Id *elements; /* pointer to elements */
int count; /* current number of elements in queue */
Id *alloc; /* this is whats actually allocated, elements > alloc if shifted */
int left; /* space left in alloc *after* elements+count */
} Queue;
extern void queue_alloc_one(Queue *q); /* internal */
extern void queue_alloc_one_head(Queue *q); /* internal */
/* clear queue */
static inline void
queue_empty(Queue *q)
{
if (q->alloc)
{
q->left += (q->elements - q->alloc) + q->count;
q->elements = q->alloc;
}
else
q->left += q->count;
q->count = 0;
}
static inline Id
queue_shift(Queue *q)
{
if (!q->count)
return 0;
q->count--;
return *q->elements++;
}
static inline Id
queue_pop(Queue *q)
{
if (!q->count)
return 0;
q->left++;
return q->elements[--q->count];
}
static inline void
queue_unshift(Queue *q, Id id)
{
if (!q->alloc || q->alloc == q->elements)
queue_alloc_one_head(q);
*--q->elements = id;
q->count++;
}
static inline void
queue_push(Queue *q, Id id)
{
if (!q->left)
queue_alloc_one(q);
q->elements[q->count++] = id;
q->left--;
}
static inline void
queue_pushunique(Queue *q, Id id)
{
int i;
for (i = q->count; i > 0; )
if (q->elements[--i] == id)
return;
queue_push(q, id);
}
static inline void
queue_push2(Queue *q, Id id1, Id id2)
{
queue_push(q, id1);
queue_push(q, id2);
}
static inline void
queue_truncate(Queue *q, int n)
{
if (q->count > n)
{
q->left += q->count - n;
q->count = n;
}
}
extern void queue_init(Queue *q);
extern void queue_init_buffer(Queue *q, Id *buf, int size);
extern void queue_init_clone(Queue *target, const Queue *source);
extern void queue_free(Queue *q);
extern void queue_insert(Queue *q, int pos, Id id);
extern void queue_insert2(Queue *q, int pos, Id id1, Id id2);
extern void queue_insertn(Queue *q, int pos, int n, const Id *elements);
extern void queue_delete(Queue *q, int pos);
extern void queue_delete2(Queue *q, int pos);
extern void queue_deleten(Queue *q, int pos, int n);
extern void queue_prealloc(Queue *q, int n);
#ifdef __cplusplus
}
#endif
#endif /* LIBSOLV_QUEUE_H */