minix/include/sys/gcq.h

464 lines
16 KiB
C
Raw Normal View History

2011-02-21 14:13:55 +01:00
/* $NetBSD: gcq.h,v 1.2 2007/08/19 07:35:32 kiyohara Exp $ */
/*
* Not (c) 2007 Matthew Orgass
* This file is public domain, meaning anyone can make any use of part or all
* of this file including copying into other works without credit. Any use,
* modified or not, is solely the responsibility of the user. If this file is
* part of a collection then use in the collection is governed by the terms of
* the collection.
*/
/*
* Generic Circular Queues: Pointer arithmetic is used to recover the
* enclosing object. Merge operation is provided. Items can be multiply
* removed, but queue traversal requires separate knowledge of the queue head.
*/
#ifndef _GCQ_H
#define _GCQ_H
#ifdef _KERNEL
#include <sys/types.h>
#include <sys/null.h>
#include <lib/libkern/libkern.h>
#else
#include <stdbool.h>
#include <stdint.h>
#include <stddef.h>
#include <assert.h>
#endif
#ifdef GCQ_USE_ASSERT
#define GCQ_ASSERT(x) assert(x)
#else
#ifdef _KERNEL
#define GCQ_ASSERT(x) KASSERT(x)
#else
#define GCQ_ASSERT(x) _DIAGASSERT(x)
#endif
#endif
struct gcq {
struct gcq *q_next;
struct gcq *q_prev;
};
struct gcq_head {
struct gcq hq;
};
#define GCQ_INIT(q) { &(q), &(q) }
#define GCQ_INIT_HEAD(head) { GCQ_INIT((head).hq) }
__attribute__((nonnull, always_inline)) static inline void
gcq_init(struct gcq *q)
{
q->q_next = q->q_prev = q;
}
__attribute__((nonnull, const, warn_unused_result, always_inline))
static inline struct gcq *
gcq_q(struct gcq *q)
{
return q;
}
__attribute__((nonnull, const, warn_unused_result, always_inline))
static inline struct gcq *
gcq_hq(struct gcq_head *head)
{
return (struct gcq *)head;
}
__attribute__((nonnull, const, warn_unused_result, always_inline))
static inline struct gcq_head *
gcq_head(struct gcq *q)
{
return (struct gcq_head *)q;
}
__attribute__((nonnull, always_inline)) static inline void
gcq_init_head(struct gcq_head *head)
{
gcq_init(gcq_hq(head));
}
__attribute__((nonnull, pure, warn_unused_result, always_inline))
static inline bool
gcq_onlist(struct gcq *q)
{
return (q->q_next != q);
}
__attribute__((nonnull, pure, warn_unused_result, always_inline))
static inline bool
gcq_empty(struct gcq_head *head)
{
return (!gcq_onlist(gcq_hq(head)));
}
__attribute__((nonnull, pure, warn_unused_result, always_inline))
static inline bool
gcq_linked(struct gcq *prev, struct gcq *next)
{
return (prev->q_next == next && next->q_prev == prev);
}
__attribute__((nonnull, always_inline)) static inline void
gcq_insert_after(struct gcq *on, struct gcq *off)
{
struct gcq *on_next;
GCQ_ASSERT(off->q_next == off && off->q_prev == off);
on_next = on->q_next;
off->q_prev = on;
off->q_next = on_next;
on_next->q_prev = off;
on->q_next = off;
}
__attribute__((nonnull)) static inline void
gcq_insert_before(struct gcq *on, struct gcq *off)
{
struct gcq *on_prev;
GCQ_ASSERT(off->q_next == off && off->q_prev == off);
on_prev = on->q_prev;
off->q_next = on;
off->q_prev = on_prev;
on_prev->q_next = off;
on->q_prev = off;
}
__attribute__((nonnull, always_inline)) static inline void
gcq_insert_head(struct gcq_head *head, struct gcq *q)
{
gcq_insert_after(gcq_hq(head), q);
}
__attribute__((nonnull, always_inline)) static inline void
gcq_insert_tail(struct gcq_head *head, struct gcq *q)
{
gcq_insert_before(gcq_hq(head), q);
}
__attribute__((nonnull)) static inline void
gcq_tie(struct gcq *dst, struct gcq *src)
{
struct gcq *dst_next, *src_prev;
dst_next = dst->q_next;
src_prev = src->q_prev;
src_prev->q_next = dst_next;
dst_next->q_prev = src_prev;
src->q_prev = dst;
dst->q_next = src;
}
__attribute__((nonnull, always_inline)) static inline void
gcq_tie_after(struct gcq *dst, struct gcq *src)
{
GCQ_ASSERT(dst != src && dst->q_prev != src);
gcq_tie(dst, src);
}
__attribute__((nonnull, always_inline)) static inline void
gcq_tie_before(struct gcq *dst, struct gcq *src)
{
gcq_tie_after(dst->q_prev, src);
}
__attribute__((nonnull)) static inline struct gcq *
gcq_remove(struct gcq *q)
{
struct gcq *next, *prev;
next = q->q_next;
prev = q->q_prev;
prev->q_next = next;
next->q_prev = prev;
gcq_init(q);
return q;
}
#ifdef GCQ_UNCONDITIONAL_MERGE
__attribute__((nonnull)) static inline void
gcq_merge(struct gcq *dst, struct gcq *src)
{
GCQ_ASSERT(dst != src && dst->q_prev != src);
gcq_tie(dst, src);
gcq_tie(src, src);
}
__attribute__((nonnull, always_inline)) static inline void
gcq_merge_head(struct gcq_head *dst, struct gcq_head *src)
{
gcq_merge(gcq_hq(dst), gcq_hq(src));
}
__attribute__((nonnull, always_inline)) static inline void
gcq_merge_tail(struct gcq_head *dst, struct gcq_head *src)
{
gcq_merge(gcq_hq(dst)->q_prev, gcq_hq(src));
}
#else
__attribute__((nonnull)) static inline void
gcq_merge(struct gcq *dst, struct gcq *src)
{
struct gcq *dst_next, *src_prev, *src_next;
GCQ_ASSERT(dst != src && dst->q_prev != src);
if (gcq_onlist(src)) {
dst_next = dst->q_next;
src_prev = src->q_prev;
src_next = src->q_next;
dst_next->q_prev = src_prev;
src_prev->q_next = dst_next;
dst->q_next = src_next;
src_next->q_prev = dst;
gcq_init(src);
}
}
__attribute__((nonnull, always_inline)) static inline void
gcq_merge_head(struct gcq_head *dst, struct gcq_head *src)
{
gcq_merge(gcq_hq(dst), gcq_hq(src));
}
__attribute__((nonnull, always_inline)) static inline void
gcq_merge_tail(struct gcq_head *dst, struct gcq_head *src)
{
gcq_merge(gcq_hq(dst)->q_prev, gcq_hq(src));
}
#endif
__attribute__((nonnull)) static inline void
gcq_clear(struct gcq *q)
{
struct gcq *nq, *next;
nq=q;
do {
next = nq->q_next;
gcq_init(nq);
nq = next;
} while (next != q);
}
__attribute__((nonnull, always_inline)) static inline void
gcq_remove_all(struct gcq_head *head)
{
gcq_clear(gcq_hq(head));
}
__attribute__((nonnull, always_inline)) static inline struct gcq *
_gcq_next(struct gcq *current, struct gcq_head *head, struct gcq *start)
{
struct gcq *q, *hq;
hq = gcq_hq(head);
q = current->q_next;
if (hq != start && q == hq)
q = hq->q_next;
if (current != start)
GCQ_ASSERT(gcq_onlist(current));
return q;
}
__attribute__((nonnull, always_inline)) static inline struct gcq *
_gcq_prev(struct gcq *current, struct gcq_head *head, struct gcq *start)
{
struct gcq *q, *hq;
hq = gcq_hq(head);
q = current->q_prev;
if (hq != start && q == hq)
q = hq->q_prev;
if (current != start)
GCQ_ASSERT(gcq_onlist(current));
return q;
}
#define GCQ_ITEM(q, type, name) \
((type *)(void *)((uint8_t *)gcq_q(q) - offsetof(type, name)))
#define _GCQ_GDQ(var, h, ptr, fn) (gcq_hq(h)->ptr != gcq_hq(h) ? \
(var = fn(gcq_hq(h)->ptr), true) : (var = NULL, false))
#define _GCQ_GDQ_TYPED(tvar, h, type, name, ptr, fn) \
(gcq_hq(h)->ptr != gcq_hq(h) ? (tvar = GCQ_ITEM(fn(gcq_hq(h)->ptr), \
type, name), true) : (tvar = NULL, false))
#define _GCQ_NP(var, current, head, start, np, fn) \
(np(current, head, start) != (start) ? \
(var = fn(np(current, head, start)), true) : (var = NULL, false))
#define _GCQ_NP_TYPED(tvar, current, head, start, type, name, np, fn) \
(np(current, head, start) != (start) ? \
(tvar = GCQ_ITEM(fn(np(current, head, start)), type, name), true) : \
(tvar = NULL, false))
#define _GCQ_GDQ_COND(var, h, ptr, rem, cond) \
(gcq_hq(h)->ptr != gcq_hq(h) ? (var = gcq_hq(h)->ptr, \
((cond) ? (rem, true) : (var = NULL, false))) : \
(var = NULL, false))
#define _GCQ_GDQ_COND_TYPED(tvar, h, type, name, ptr, rem, cond) \
(gcq_hq(h)->ptr != gcq_hq(h) ? (tvar = GCQ_ITEM(gcq_hq(h)->ptr, \
type, name), ((cond) ? (rem, true) : (tvar = NULL, false))) : \
(tvar = NULL, false))
#define _GCQ_NP_COND(var, current, head, start, np, rem, cond) \
(np(current, head, start) != (start) ? \
(var = fn(np(current, head, start)), ((cond) ? (rem), true) : \
(var = NULL, false))) : (var = NULL, false))
#define _GCQ_NP_COND_TYPED(tvar, current, head, start, type, name, np, \
rem, cond) (np(current, head, start) != (start) ? \
(tvar = GCQ_ITEM(fn(np(current, head, start)), type, name), \
((cond) ? (rem, true) : (var = NULL, false))) : \
(tvar = NULL, false))
#define GCQ_GOT_FIRST(var, h) _GCQ_GDQ(var, h, q_next, gcq_q)
#define GCQ_GOT_LAST(var, h) _GCQ_GDQ(var, h, q_prev, gcq_q)
#define GCQ_DEQUEUED_FIRST(var, h) _GCQ_GDQ(var, h, q_next, gcq_remove)
#define GCQ_DEQUEUED_LAST(var, h) _GCQ_GDQ(var, h, q_prev, gcq_remove)
#define GCQ_GOT_FIRST_TYPED(tvar, h, type, name) \
_GCQ_GDQ_TYPED(tvar, h, type, name, q_next, gcq_q)
#define GCQ_GOT_LAST_TYPED(tvar, h, type, name) \
_GCQ_GDQ_TYPED(tvar, h, type, name, q_prev, gcq_q)
#define GCQ_DEQUEUED_FIRST_TYPED(tvar, h, type, name) \
_GCQ_GDQ_TYPED(tvar, h, type, name, q_next, gcq_remove)
#define GCQ_DEQUEUED_LAST_TYPED(tvar, h, type, name) \
_GCQ_GDQ_TYPED(tvar, h, type, name, q_prev, gcq_remove)
#define GCQ_GOT_NEXT(var, current, head, start) \
_GCQ_NP(var, current, head, start, _gcq_next, gcq_q)
#define GCQ_GOT_PREV(var, current, head, start) \
_GCQ_NP(var, current, head, start, _gcq_prev, gcq_q)
#define GCQ_DEQUEUED_NEXT(var, current, head, start) \
_GCQ_NP(var, current, head, start, _gcq_next, gcq_remove)
#define GCQ_DEQUEUED_PREV(var, current, head, start) \
_GCQ_NP(var, current, head, start, _gcq_prev, gcq_remove)
#define GCQ_GOT_NEXT_TYPED(tvar, current, head, start, type, name) \
_GCQ_NP_TYPED(tvar, current, head, start, type, name, \
_gcq_next, gcq_q)
#define GCQ_GOT_PREV_TYPED(tvar, current, head, start, type, name) \
_GCQ_NP_TYPED(tvar, current, head, start, type, name, \
_gcq_prev, gcq_q)
#define GCQ_DEQUEUED_NEXT_TYPED(tvar, current, head, start, type, name) \
_GCQ_NP_TYPED(tvar, current, head, start, type, name, \
_gcq_next, gcq_remove)
#define GCQ_DEQUEUED_PREV_TYPED(tvar, current, head, start, type, name) \
_GCQ_NP_TYPED(tvar, current, head, start, type, name, \
_gcq_prev, gcq_remove)
#define GCQ_GOT_FIRST_COND(var, h, cond) \
_GCQ_GDQ_COND(var, h, q_next, ((void)0), cond)
#define GCQ_GOT_LAST_COND(var, h, cond) \
_GCQ_GDQ_COND(var, h, q_prev, ((void)0), cond)
#define GCQ_DEQUEUED_FIRST_COND(var, h, cond) \
_GCQ_GDQ_COND(var, h, q_next, gcq_remove(var), cond)
#define GCQ_DEQUEUED_LAST_COND(var, h, cond) \
_GCQ_GDQ_COND(var, h, q_prev, gcq_remove(var), cond)
#define GCQ_GOT_FIRST_COND_TYPED(tvar, h, type, name, cond) \
_GCQ_GDQ_COND_TYPED(tvar, h, type, name, q_next, ((void)0), cond)
#define GCQ_GOT_LAST_COND_TYPED(tvar, h, type, name, cond) \
_GCQ_GDQ_COND_TYPED(tvar, h, type, name, q_prev, ((void)0), cond)
#define GCQ_DEQUEUED_FIRST_COND_TYPED(tvar, h, type, name, cond) \
_GCQ_GDQ_COND_TYPED(tvar, h, type, name, q_next, \
gcq_remove(&(tvar)->name), cond)
#define GCQ_DEQUEUED_LAST_COND_TYPED(tvar, h, type, name, cond) \
_GCQ_GDQ_COND_TYPED(tvar, h, type, name, q_prev, \
gcq_remove(&(tvar)->name), cond)
#define GCQ_GOT_NEXT_COND(var, current, head, start, cond) \
_GCQ_NP_COND(var, current, head, start, _gcq_next, ((void)0), cond)
#define GCQ_GOT_PREV_COND(var, current, head, start, cond) \
_GCQ_NP_COND(var, current, head, start, _gcq_prev, ((void)0), cond)
#define GCQ_DEQUEUED_NEXT_COND(var, current, head, start, cond) \
_GCQ_NP_COND(var, current, head, start, _gcq_next, gcq_remove(var), \
cond)
#define GCQ_DEQUEUED_PREV_COND(var, current, head, start, cond) \
_GCQ_NP_COND(var, current, head, start, _gcq_prev, gcq_remove(var), \
cond)
#define GCQ_GOT_NEXT_COND_TYPED(tvar, current, head, start, type, name, \
cond) _GCQ_NP_COND_TYPED(tvar, current, head, start, type, name, \
_gcq_next, ((void)0), cond)
#define GCQ_GOT_PREV_COND_TYPED(tvar, current, head, start, type, name, \
cond) _GCQ_NP_COND_TYPED(tvar, current, head, start, type, name, \
_gcq_prev, ((void)0), cond)
#define GCQ_DEQUEUED_NEXT_COND_TYPED(tvar, current, head, start, type, \
name, cond) _GCQ_NP_COND_TYPED(tvar, current, head, start, type, \
name, _gcq_next, gcq_remove(&(tvar)->name), cond)
#define GCQ_DEQUEUED_PREV_COND_TYPED(tvar, current, head, start, type, \
name, cond) _GCQ_NP_COND_TYPED(tvar, current, head, start, type, \
name, _gcq_prev, gcq_remove(&(tvar)->name), cond)
#define _GCQ_FOREACH(var, h, tnull, item, ptr) \
for ((var)=gcq_hq(h)->ptr; ((var) != gcq_hq(h) && \
(GCQ_ASSERT(gcq_onlist(var)), item, true)) || \
(tnull, false); (var)=(var)->ptr)
#define _GCQ_FOREACH_NVAR(var, nvar, h, tnull, item, ptr, ol, rem, ro) \
for ((nvar)=gcq_hq(h)->ptr; (((var)=(nvar), (nvar) != gcq_hq(h)) && \
(ol, (nvar)=(nvar)->ptr, rem, item, true)) || (tnull, false); ro)
#define GCQ_FOREACH(var, h) \
_GCQ_FOREACH(var, h, ((void)0), ((void)0), q_next)
#define GCQ_FOREACH_REV(var, h) \
_GCQ_FOREACH(var, h, ((void)0), ((void)0), q_prev)
#define GCQ_FOREACH_NVAR(var, nvar, h) \
_GCQ_FOREACH_NVAR(var, nvar, h, ((void)0), ((void)0), \
q_next, GCQ_ASSERT(gcq_onlist(nvar)), ((void)0), ((void)0))
#define GCQ_FOREACH_NVAR_REV(var, nvar, h) \
_GCQ_FOREACH_NVAR(var, nvar, h, ((void)0), ((void)0), \
q_prev, GCQ_ASSERT(gcq_onlist(nvar)), ((void)0), ((void)0))
#define GCQ_FOREACH_RO(var, nvar, h) \
_GCQ_FOREACH_NVAR(var, nvar, h, ((void)0), ((void)0), \
q_next, ((void)0), ((void)0), GCQ_ASSERT(gcq_linked(var, nvar)))
#define GCQ_FOREACH_RO_REV(var, nvar, h) \
_GCQ_FOREACH_NVAR(var, nvar, h, ((void)0), ((void)0), \
q_prev, ((void)0), ((void)0), GCQ_ASSERT(gcq_linked(nvar, var)))
#define GCQ_FOREACH_DEQUEUED(var, nvar, h) \
_GCQ_FOREACH_NVAR(var, nvar, h, ((void)0), ((void)0), \
q_next, GCQ_ASSERT(gcq_onlist(nvar)), gcq_remove(var), ((void)0)
#define GCQ_FOREACH_DEQUEUED_REV(var, nvar, h) \
_GCQ_FOREACH_NVAR(var, nvar, h, ((void)0), ((void)0), \
q_prev, GCQ_ASSERT(gcq_onlist(nvar)), gcq_remove(var), ((void)0)
#define GCQ_FOREACH_TYPED(var, h, tvar, type, name) \
_GCQ_FOREACH(var, h, (tvar)=NULL, (tvar)=GCQ_ITEM(var, type, name), \
q_next)
#define GCQ_FOREACH_TYPED_REV(var, h, tvar, type, name) \
_GCQ_FOREACH(var, h, (tvar)=NULL, (tvar)=GCQ_ITEM(var, type, name), \
q_prev)
#define GCQ_FOREACH_NVAR_TYPED(var, nvar, h, tvar, type, name) \
_GCQ_FOREACH_NVAR(var, nvar, h, (tvar)=NULL, \
(tvar)=GCQ_ITEM(var, type, name), \
q_next, GCQ_ASSERT(gcq_onlist(nvar)), ((void)0), ((void)0))
#define GCQ_FOREACH_NVAR_REV_TYPED(var, nvar, h, tvar, type, name) \
_GCQ_FOREACH_NVAR(var, nvar, h, (tvar)=NULL, \
(tvar)=GCQ_ITEM(var, type, name), \
q_prev, GCQ_ASSERT(gcq_onlist(nvar)), ((void)0), ((void)0))
#define GCQ_FOREACH_RO_TYPED(var, nvar, h, tvar, type, name) \
_GCQ_FOREACH_NVAR(var, nvar, h, (tvar)=NULL, \
(tvar)=GCQ_ITEM(var, type, name), \
q_next, ((void)0), ((void)0), GCQ_ASSERT(gcq_lined(var, nvar)))
#define GCQ_FOREACH_RO_REV_TYPED(var, nvar, h, tvar, type, name) \
_GCQ_FOREACH_NVAR(var, nvar, h, (tvar)=NULL, \
(tvar)=GCQ_ITEM(var, type, name), \
q_prev, ((void)0), ((void)0), GCQ_ASSERT(gcq_linked(nvar, var)))
#define GCQ_FOREACH_DEQUEUED_TYPED(var, nvar, h, tvar, type, name) \
_GCQ_FOREACH_NVAR(var, nvar, h, (tvar)=NULL, \
(tvar)=GCQ_ITEM(var, type, name), \
q_next, GCQ_ASSERT(gcq_onlist(nvar)), gcq_remove(var), ((void)0))
#define GCQ_FOREACH_DEQUEUED_REV_TYPED(var, nvar, h, tvar, type, name) \
_GCQ_FOREACH_NVAR(var, nvar, h, (tvar)=NULL, \
(tvar)=GCQ_ITEM(var, type, name), \
q_prev, GCQ_ASSERT(gcq_onlist(nvar)), gcq_remove(var), ((void)0))
#define _GCQ_COND(fe, cond) do { fe { if (cond) break; } } while (0)
#define GCQ_FIND(var, h, cond) _GCQ_COND(GCQ_FOREACH(var, h), cond)
#define GCQ_FIND_REV(var, h, cond) _GCQ_COND(GCQ_FOREACH_REV(var, h), cond)
#define GCQ_FIND_TYPED(var, h, tvar, type, name, cond) \
_GCQ_COND(GCQ_FOREACH_TYPED(var, h, tvar, type, name), cond)
#define GCQ_FIND_TYPED_REV(var, h, tvar, type, name, cond) \
_GCQ_COND(GCQ_FOREACH_REV_TYPED(var, h, tvar, type, name), cond)
#endif /* _GCQ_H */