/**************************************************************
 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * 
 *************************************************************/


#define _BSD_SOURCE /* sys/mman.h: MAP_ANON */
#include "alloc_arena.h"

#include "alloc_impl.h"
#include "internal/once.h"
#include "sal/macros.h"
#include "osl/diagnose.h"

#include <string.h>
#include <stdio.h>

#ifdef OS2
#undef OSL_TRACE
#define OSL_TRACE                  1 ? ((void)0) : _OSL_GLOBAL osl_trace
#define INCL_DOS
#include <os2.h>
#endif

/* ================================================================= *
 *
 * arena internals.
 *
 * ================================================================= */

/** g_arena_list
 *  @internal
 */
struct rtl_arena_list_st
{
	rtl_memory_lock_type m_lock;
	rtl_arena_type       m_arena_head;
};

static struct rtl_arena_list_st g_arena_list;


/** gp_arena_arena
 *  provided for arena_type allocations, and hash_table resizing.
 *
 *  @internal
 */
static rtl_arena_type * gp_arena_arena = 0;


/** gp_machdep_arena
 *
 *  Low level virtual memory (pseudo) arena
 *  (platform dependent implementation)
 *
 *  @internal
 */
static rtl_arena_type * gp_machdep_arena = 0;


static void *
SAL_CALL rtl_machdep_alloc (
	rtl_arena_type * pArena,
	sal_Size *       pSize
);

static void
SAL_CALL rtl_machdep_free (
	rtl_arena_type * pArena,
	void *           pAddr,
	sal_Size         nSize
);

static sal_Size
rtl_machdep_pagesize (void);


/** gp_default_arena
 */
rtl_arena_type * gp_default_arena = 0;


/** rtl_arena_init()
 *  @internal
 */
static int
rtl_arena_init (void);


/* ================================================================= */

/** rtl_arena_segment_constructor()
 */
static int
rtl_arena_segment_constructor (void * obj)
{
	rtl_arena_segment_type * segment = (rtl_arena_segment_type*)(obj);

	QUEUE_START_NAMED(segment, s);
	QUEUE_START_NAMED(segment, f);

	return (1);
}


/** rtl_arena_segment_destructor()
 */
static void
rtl_arena_segment_destructor (void * obj)
{
#if OSL_DEBUG_LEVEL == 0
    (void) obj; /* unused */
#else /* OSL_DEBUG_LEVEL */
	rtl_arena_segment_type * segment = (rtl_arena_segment_type*)(obj);

	OSL_ASSERT(QUEUE_STARTED_NAMED(segment, s));
	OSL_ASSERT(QUEUE_STARTED_NAMED(segment, f));
#endif /* OSL_DEBUG_LEVEL */
}

/* ================================================================= */

/** rtl_arena_segment_populate()
 *
 *  @precond  arena->m_lock acquired.
 */
static int
rtl_arena_segment_populate (
	rtl_arena_type * arena
)
{
    rtl_arena_segment_type *span;
	sal_Size                size = rtl_machdep_pagesize();

    span = rtl_machdep_alloc(gp_machdep_arena, &size);
	if (span != 0)
	{
        rtl_arena_segment_type *first, *last, *head;
		sal_Size                count = size / sizeof(rtl_arena_segment_type);

		/* insert onto reserve span list */
		QUEUE_INSERT_TAIL_NAMED(&(arena->m_segment_reserve_span_head), span, s);
		QUEUE_START_NAMED(span, f);
		span->m_addr = (sal_uIntPtr)(span);
		span->m_size = size;
		span->m_type = RTL_ARENA_SEGMENT_TYPE_SPAN;

		/* insert onto reserve list */
		head  = &(arena->m_segment_reserve_head);
		for (first = span + 1, last = span + count; first < last; ++first)
		{
		    QUEUE_INSERT_TAIL_NAMED(head, first, s);
			QUEUE_START_NAMED(first, f);
			first->m_addr = 0;
			first->m_size = 0;
			first->m_type = 0;
		}
	}
	return (span != 0);
}


/** rtl_arena_segment_get()
 *
 *  @precond  arena->m_lock acquired.
 *  @precond  (*ppSegment == 0)
 */
static RTL_MEMORY_INLINE void
rtl_arena_segment_get (
	rtl_arena_type *          arena,
	rtl_arena_segment_type ** ppSegment
)
{
    rtl_arena_segment_type * head;

    OSL_ASSERT(*ppSegment == 0);

    head = &(arena->m_segment_reserve_head);
    if ((head->m_snext != head) || rtl_arena_segment_populate (arena))
    {
		(*ppSegment) = head->m_snext;
		QUEUE_REMOVE_NAMED((*ppSegment), s);
    }
}

#if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
#pragma inline(rtl_arena_segment_get)
#endif


/** rtl_arena_segment_put()
 *
 *  @precond  arena->m_lock acquired.
 *  @postcond (*ppSegment == 0)
 */
static RTL_MEMORY_INLINE void
rtl_arena_segment_put (
	rtl_arena_type *          arena,
	rtl_arena_segment_type ** ppSegment
)
{
	rtl_arena_segment_type * head;

	OSL_ASSERT(QUEUE_STARTED_NAMED((*ppSegment), s));
	OSL_ASSERT(QUEUE_STARTED_NAMED((*ppSegment), f));

	(*ppSegment)->m_addr = 0;
	(*ppSegment)->m_size = 0;

	OSL_ASSERT((*ppSegment)->m_type != RTL_ARENA_SEGMENT_TYPE_HEAD);
	(*ppSegment)->m_type = 0;

	/* keep as reserve */
	head = &(arena->m_segment_reserve_head);
	QUEUE_INSERT_HEAD_NAMED(head, (*ppSegment), s);

	/* clear */
	(*ppSegment) = 0;
}

#if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
#pragma inline(rtl_arena_segment_put)
#endif

/* ================================================================= */

/** rtl_arena_freelist_insert()
 *
 *  @precond arena->m_lock acquired.
 */
static RTL_MEMORY_INLINE void
rtl_arena_freelist_insert (
	rtl_arena_type *         arena,
	rtl_arena_segment_type * segment
)
{
	rtl_arena_segment_type * head;

	head = &(arena->m_freelist_head[highbit(segment->m_size) - 1]);
	QUEUE_INSERT_TAIL_NAMED(head, segment, f);

	arena->m_freelist_bitmap |= head->m_size;
}

#if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
#pragma inline(rtl_arena_freelist_insert)
#endif /* __SUNPRO_C */


/** rtl_arena_freelist_remove()
 *
 *  @precond arena->m_lock acquired.
 */
static RTL_MEMORY_INLINE void
rtl_arena_freelist_remove (
	rtl_arena_type *         arena,
	rtl_arena_segment_type * segment
)
{
	if ((segment->m_fnext->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD) &&
		(segment->m_fprev->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD)    )
	{
		rtl_arena_segment_type * head;

		head = segment->m_fprev;
		OSL_ASSERT(arena->m_freelist_bitmap & head->m_size);
		arena->m_freelist_bitmap ^= head->m_size;
	}
	QUEUE_REMOVE_NAMED(segment, f);
}

#if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
#pragma inline(rtl_arena_freelist_remove)
#endif /* __SUNPRO_C */


/* ================================================================= */

/** RTL_ARENA_HASH_INDEX()
 */
#define	RTL_ARENA_HASH_INDEX_IMPL(a, s, q, m) \
 	((((a) + ((a) >> (s)) + ((a) >> ((s) << 1))) >> (q)) & (m))
 
#define	RTL_ARENA_HASH_INDEX(arena, addr) \
    RTL_ARENA_HASH_INDEX_IMPL((addr), (arena)->m_hash_shift, (arena)->m_quantum_shift, ((arena)->m_hash_size - 1))

/** rtl_arena_hash_rescale()
 *
 * @precond arena->m_lock released.
 */
static void
rtl_arena_hash_rescale (
	rtl_arena_type * arena,
	sal_Size         new_size
)
{
	rtl_arena_segment_type ** new_table;
	sal_Size                  new_bytes;

	new_bytes = new_size * sizeof(rtl_arena_segment_type*);
	new_table = (rtl_arena_segment_type **)rtl_arena_alloc (gp_arena_arena, &new_bytes);

	if (new_table != 0)
	{
		rtl_arena_segment_type ** old_table;
		sal_Size                  old_size, i;

		memset (new_table, 0, new_bytes);

		RTL_MEMORY_LOCK_ACQUIRE(&(arena->m_lock));

		old_table = arena->m_hash_table;
		old_size  = arena->m_hash_size;

		OSL_TRACE(
			"rtl_arena_hash_rescale(\"%s\"): "
			"nseg: %"PRIu64" (ave: %"PRIu64"), frees: %"PRIu64" "
			"[old_size: %lu, new_size: %lu]",
			arena->m_name,
			arena->m_stats.m_alloc - arena->m_stats.m_free,
			(arena->m_stats.m_alloc - arena->m_stats.m_free) >> arena->m_hash_shift,
			arena->m_stats.m_free,
			old_size, new_size
		);

#if 0  /* DBG */
		for (i = 0; i < arena->m_hash_size; i++)
		{
			sal_Size k = 0; rtl_arena_segment_type ** segpp = &(arena->m_hash_table[i]);
			while (*segpp)
			{
				k += 1;
				segpp = &((*segpp)->m_fnext);
			}
			fprintf(stdout, "%d, ", k);
		}
		fprintf(stdout, "\n");
#endif /* DBG */

		arena->m_hash_table = new_table;
		arena->m_hash_size  = new_size;
		arena->m_hash_shift = highbit(arena->m_hash_size) - 1;

		for (i = 0; i < old_size; i++)
		{
			rtl_arena_segment_type * curr = old_table[i];
			while (curr != 0)
			{
				rtl_arena_segment_type  * next = curr->m_fnext;
				rtl_arena_segment_type ** head;

				head = &(arena->m_hash_table[RTL_ARENA_HASH_INDEX(arena, curr->m_addr)]);
				curr->m_fnext = (*head);
				(*head) = curr;

				curr = next;
			}
			old_table[i] = 0;
		}

		RTL_MEMORY_LOCK_RELEASE(&(arena->m_lock));

		if (old_table != arena->m_hash_table_0)
		{
			sal_Size old_bytes = old_size * sizeof(rtl_arena_segment_type*);
			rtl_arena_free (gp_arena_arena, old_table, old_bytes);
		}
	}
}


/** rtl_arena_hash_insert()
 *  ...and update stats.
 */
static RTL_MEMORY_INLINE void
rtl_arena_hash_insert (
	rtl_arena_type *         arena,
	rtl_arena_segment_type * segment
)
{
	rtl_arena_segment_type ** ppSegment;

	ppSegment = &(arena->m_hash_table[RTL_ARENA_HASH_INDEX(arena, segment->m_addr)]);

	segment->m_fnext = (*ppSegment);
	(*ppSegment) = segment;

	arena->m_stats.m_alloc     += 1;
	arena->m_stats.m_mem_alloc += segment->m_size;
}

#if defined(__SUNPRO_C) || defined(__SUNPRO_CC)
#pragma inline(rtl_arena_hash_insert)
#endif /* __SUNPRO_C */


/** rtl_arena_hash_remove()
 *  ...and update stats.
 */
static rtl_arena_segment_type *
rtl_arena_hash_remove (
	rtl_arena_type * arena,
	sal_uIntPtr      addr,
	sal_Size         size
)
{
	rtl_arena_segment_type *segment, **segpp;
	sal_Size lookups = 0;

#if OSL_DEBUG_LEVEL == 0
    (void) size; /* unused */
#endif /* OSL_DEBUG_LEVEL */

	segpp = &(arena->m_hash_table[RTL_ARENA_HASH_INDEX(arena, addr)]);
	while ((segment = *segpp) != 0)
	{
		if (segment->m_addr == addr)
		{
			*segpp = segment->m_fnext, segment->m_fnext = segment->m_fprev = segment;
			break;
		}

		/* update lookup miss stats */
		lookups += 1;
		segpp = &(segment->m_fnext);
	}

	OSL_POSTCOND(segment != 0, "rtl_arena_hash_remove(): bad free.");
	if (segment != 0)
	{
		OSL_POSTCOND(segment->m_size == size, "rtl_arena_hash_remove(): wrong size.");

		arena->m_stats.m_free      += 1;
		arena->m_stats.m_mem_alloc -= segment->m_size;

		if (lookups > 1)
		{
			sal_Size nseg = (sal_Size)(arena->m_stats.m_alloc - arena->m_stats.m_free);
			if (nseg > 4 * arena->m_hash_size)
			{
				if (!(arena->m_flags & RTL_ARENA_FLAG_RESCALE))
				{
					sal_Size ave = nseg >> arena->m_hash_shift;
					sal_Size new_size = arena->m_hash_size << (highbit(ave) - 1);

					arena->m_flags |= RTL_ARENA_FLAG_RESCALE;
					RTL_MEMORY_LOCK_RELEASE(&(arena->m_lock));
					rtl_arena_hash_rescale (arena, new_size);
					RTL_MEMORY_LOCK_ACQUIRE(&(arena->m_lock));
					arena->m_flags &= ~RTL_ARENA_FLAG_RESCALE;
				}
			}
		}
	}

	return (segment);
}

/* ================================================================= */

/** rtl_arena_segment_alloc()
 *  allocate (and remove) segment from freelist
 *
 *  @precond arena->m_lock acquired
 *  @precond (*ppSegment == 0)
 */
static int
rtl_arena_segment_alloc (
	rtl_arena_type *          arena,
	sal_Size                  size,
	rtl_arena_segment_type ** ppSegment
)
{
	int index = 0;

	OSL_ASSERT(*ppSegment == 0);
	if (!RTL_MEMORY_ISP2(size))
	{
		int msb = highbit(size);
		if (RTL_ARENA_FREELIST_SIZE == SAL_INT_CAST(size_t, msb))
		{
			/* highest possible freelist: fall back to first fit */
			rtl_arena_segment_type *head, *segment;

			head = &(arena->m_freelist_head[msb - 1]);
			for (segment = head->m_fnext; segment != head; segment = segment->m_fnext)
			{
				if (segment->m_size >= size)
				{
					/* allocate first fit segment */
					(*ppSegment) = segment;
					break;
				}
			}
			goto dequeue_and_leave;
		}

		/* roundup to next power of 2 */
		size = (1UL << msb);
	}

	index = lowbit(RTL_MEMORY_P2ALIGN(arena->m_freelist_bitmap, size));
	if (index > 0)
	{
		/* instant fit: allocate first free segment */
		rtl_arena_segment_type *head;

		head = &(arena->m_freelist_head[index - 1]);
		(*ppSegment) = head->m_fnext;
		OSL_ASSERT((*ppSegment) != head);
	}

dequeue_and_leave:
	if (*ppSegment != 0)
	{
		/* remove from freelist */
		rtl_arena_freelist_remove (arena, (*ppSegment));
	}
	return (*ppSegment != 0);
}


/** rtl_arena_segment_create()
 *  import new (span) segment from source arena
 *
 *  @precond arena->m_lock acquired
 *  @precond (*ppSegment == 0)
 */
static int
rtl_arena_segment_create (
	rtl_arena_type *          arena,
	sal_Size                  size,
	rtl_arena_segment_type ** ppSegment
)
{
	OSL_ASSERT((*ppSegment) == 0);
	if (arena->m_source_alloc != 0)
	{
		rtl_arena_segment_get (arena, ppSegment);
		if (*ppSegment != 0)
		{
			rtl_arena_segment_type * span = 0;
			rtl_arena_segment_get (arena, &span);
			if (span != 0)
			{
				/* import new span from source arena */
				RTL_MEMORY_LOCK_RELEASE(&(arena->m_lock));

				span->m_size = size;
				span->m_addr = (sal_uIntPtr)(arena->m_source_alloc)(
					arena->m_source_arena, &(span->m_size));

				RTL_MEMORY_LOCK_ACQUIRE(&(arena->m_lock));
				if (span->m_addr != 0)
				{
					/* insert onto segment list, update stats */
					span->m_type = RTL_ARENA_SEGMENT_TYPE_SPAN;
					QUEUE_INSERT_HEAD_NAMED(&(arena->m_segment_head), span, s);
					arena->m_stats.m_mem_total += span->m_size;

					(*ppSegment)->m_addr = span->m_addr;
					(*ppSegment)->m_size = span->m_size;
					(*ppSegment)->m_type = RTL_ARENA_SEGMENT_TYPE_FREE;
					QUEUE_INSERT_HEAD_NAMED(span, (*ppSegment), s);

					/* report success */
					return (1);
				}
				rtl_arena_segment_put (arena, &span);
			}
			rtl_arena_segment_put (arena, ppSegment);
		}
	}
	return (0);
}


/** rtl_arena_segment_coalesce()
 *  mark as free and join with adjacent free segment(s)
 *
 *  @precond arena->m_lock acquired
 *  @precond segment marked 'used'
 */
static void
rtl_arena_segment_coalesce (
	rtl_arena_type *         arena,
	rtl_arena_segment_type * segment
)
{
	rtl_arena_segment_type *next, *prev;

	/* mark segment free */
	OSL_ASSERT(segment->m_type == RTL_ARENA_SEGMENT_TYPE_USED);
	segment->m_type = RTL_ARENA_SEGMENT_TYPE_FREE;

	/* try to merge w/ next segment */
	next = segment->m_snext;
	if (next->m_type == RTL_ARENA_SEGMENT_TYPE_FREE)
	{
		OSL_ASSERT(segment->m_addr + segment->m_size == next->m_addr);
		segment->m_size += next->m_size;

		/* remove from freelist */
		rtl_arena_freelist_remove (arena, next);

		/* remove from segment list */
		QUEUE_REMOVE_NAMED(next, s);

		/* release segment descriptor */
		rtl_arena_segment_put (arena, &next);
	}

	/* try to merge w/ prev segment */
	prev = segment->m_sprev;
	if (prev->m_type == RTL_ARENA_SEGMENT_TYPE_FREE)
	{
		OSL_ASSERT(prev->m_addr + prev->m_size == segment->m_addr);
		segment->m_addr  = prev->m_addr;
		segment->m_size += prev->m_size;

		/* remove from freelist */
		rtl_arena_freelist_remove (arena, prev);

		/* remove from segment list */
		QUEUE_REMOVE_NAMED(prev, s);

		/* release segment descriptor */
		rtl_arena_segment_put (arena, &prev);
	}
}

/* ================================================================= */

/** rtl_arena_constructor()
 */
static void
rtl_arena_constructor (void * obj)
{
	rtl_arena_type * arena = (rtl_arena_type*)(obj);
	rtl_arena_segment_type * head;
	size_t i;

	memset (arena, 0, sizeof(rtl_arena_type));

	QUEUE_START_NAMED(arena, arena_);

	(void) RTL_MEMORY_LOCK_INIT(&(arena->m_lock));

	head = &(arena->m_segment_reserve_span_head);
	rtl_arena_segment_constructor (head);
	head->m_type = RTL_ARENA_SEGMENT_TYPE_HEAD;

	head = &(arena->m_segment_reserve_head);
	rtl_arena_segment_constructor (head);
	head->m_type = RTL_ARENA_SEGMENT_TYPE_HEAD;

	head = &(arena->m_segment_head);
	rtl_arena_segment_constructor (head);
	head->m_type = RTL_ARENA_SEGMENT_TYPE_HEAD;

	for (i = 0; i < RTL_ARENA_FREELIST_SIZE; i++)
	{
		head = &(arena->m_freelist_head[i]);
		rtl_arena_segment_constructor (head);

		head->m_size = (1UL << i);
		head->m_type = RTL_ARENA_SEGMENT_TYPE_HEAD;
	}

	arena->m_hash_table = arena->m_hash_table_0;
	arena->m_hash_size  = RTL_ARENA_HASH_SIZE;
	arena->m_hash_shift = highbit(arena->m_hash_size) - 1;
}


/** rtl_arena_destructor()
 */
static void
rtl_arena_destructor (void * obj)
{
	rtl_arena_type * arena = (rtl_arena_type*)(obj);
	rtl_arena_segment_type * head;
	size_t i;

	OSL_ASSERT(QUEUE_STARTED_NAMED(arena, arena_));

	RTL_MEMORY_LOCK_DESTROY(&(arena->m_lock));

	head = &(arena->m_segment_reserve_span_head);
	OSL_ASSERT(head->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD);
	rtl_arena_segment_destructor (head);

	head = &(arena->m_segment_reserve_head);
	OSL_ASSERT(head->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD);
	rtl_arena_segment_destructor (head);

	head = &(arena->m_segment_head);
	OSL_ASSERT(head->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD);
	rtl_arena_segment_destructor (head);

	for (i = 0; i < RTL_ARENA_FREELIST_SIZE; i++)
	{
		head = &(arena->m_freelist_head[i]);

		OSL_ASSERT(head->m_size == (1UL << i));
		OSL_ASSERT(head->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD);

		rtl_arena_segment_destructor (head);
	}

	OSL_ASSERT(arena->m_hash_table == arena->m_hash_table_0);
	OSL_ASSERT(arena->m_hash_size  == RTL_ARENA_HASH_SIZE);
	OSL_ASSERT(
        arena->m_hash_shift ==
        SAL_INT_CAST(unsigned, highbit(arena->m_hash_size) - 1));
}

/* ================================================================= */

/** rtl_arena_activate()
 */
static rtl_arena_type *
rtl_arena_activate (
	rtl_arena_type *   arena,
	const char *       name,
	sal_Size           quantum,
	sal_Size           quantum_cache_max,
	rtl_arena_type *   source_arena,
	void * (SAL_CALL * source_alloc)(rtl_arena_type *, sal_Size *),
	void   (SAL_CALL * source_free) (rtl_arena_type *, void *, sal_Size)
)
{
	OSL_ASSERT(arena != 0);
	if (arena != 0)
	{
		(void) snprintf (arena->m_name, sizeof(arena->m_name), "%s", name);

		if (!RTL_MEMORY_ISP2(quantum))
		{
			/* roundup to next power of 2 */
			quantum = (1UL << highbit(quantum));
		}
		quantum_cache_max = RTL_MEMORY_P2ROUNDUP(quantum_cache_max, quantum);

		arena->m_quantum = quantum;
		arena->m_quantum_shift = highbit(arena->m_quantum) - 1;
		arena->m_qcache_max = quantum_cache_max;

		arena->m_source_arena = source_arena;
		arena->m_source_alloc = source_alloc;
		arena->m_source_free  = source_free;

		if (arena->m_qcache_max > 0)
		{
			char name[RTL_ARENA_NAME_LENGTH + 1];
			int  i, n = (arena->m_qcache_max >> arena->m_quantum_shift);

			sal_Size size = n * sizeof(rtl_cache_type*);
			arena->m_qcache_ptr = (rtl_cache_type**)rtl_arena_alloc (gp_arena_arena, &size);
			if (!(arena->m_qcache_ptr))
			{
				/* out of memory */
				return (0);
			}
			for (i = 1; i <= n; i++)
			{
				size = i * arena->m_quantum;
				(void) snprintf (name, sizeof(name), "%s_%lu", arena->m_name, size);
				arena->m_qcache_ptr[i - 1] = rtl_cache_create(name, size, 0, NULL, NULL, NULL, NULL, arena, RTL_CACHE_FLAG_QUANTUMCACHE);
			}
		}

		/* insert into arena list */
		RTL_MEMORY_LOCK_ACQUIRE(&(g_arena_list.m_lock));
		QUEUE_INSERT_TAIL_NAMED(&(g_arena_list.m_arena_head), arena, arena_);
		RTL_MEMORY_LOCK_RELEASE(&(g_arena_list.m_lock));
	}
	return (arena);
}

/** rtl_arena_deactivate()
 */
static void
rtl_arena_deactivate (
	rtl_arena_type * arena
)
{
	rtl_arena_segment_type * head, * segment;

	/* remove from arena list */
	RTL_MEMORY_LOCK_ACQUIRE(&(g_arena_list.m_lock));
	QUEUE_REMOVE_NAMED(arena, arena_);
	RTL_MEMORY_LOCK_RELEASE(&(g_arena_list.m_lock));

	/* cleanup quantum cache(s) */
	if ((arena->m_qcache_max > 0) && (arena->m_qcache_ptr != 0))
	{
		int  i, n = (arena->m_qcache_max >> arena->m_quantum_shift);
		for (i = 1; i <= n; i++)
		{
			if (arena->m_qcache_ptr[i - 1] != 0)
			{
				rtl_cache_destroy (arena->m_qcache_ptr[i - 1]);
				arena->m_qcache_ptr[i - 1] = 0;
			}
		}
		rtl_arena_free (
			gp_arena_arena,
			arena->m_qcache_ptr,
			n * sizeof(rtl_cache_type*));

		arena->m_qcache_ptr = 0;
	}

	/* check for leaked segments */
	OSL_TRACE(
		"rtl_arena_deactivate(\"%s\"): "
		"allocs: %"PRIu64", frees: %"PRIu64"; total: %lu, used: %lu",
		arena->m_name,
		arena->m_stats.m_alloc, arena->m_stats.m_free,
		arena->m_stats.m_mem_total, arena->m_stats.m_mem_alloc
	);
	if (arena->m_stats.m_alloc > arena->m_stats.m_free)
	{
		sal_Size i, n;

		OSL_TRACE(
			"rtl_arena_deactivate(\"%s\"): "
			"cleaning up %"PRIu64" leaked segment(s) [%lu bytes]",
			arena->m_name,
			arena->m_stats.m_alloc - arena->m_stats.m_free,
			arena->m_stats.m_mem_alloc
		);

		/* cleanup still used segment(s) */
		for (i = 0, n = arena->m_hash_size; i < n; i++)
		{
			while ((segment = arena->m_hash_table[i]) != 0)
			{
				/* pop from hash table */
				arena->m_hash_table[i] = segment->m_fnext, segment->m_fnext = segment->m_fprev = segment;

				/* coalesce w/ adjacent free segment(s) */
				rtl_arena_segment_coalesce (arena, segment);

				/* insert onto freelist */
				rtl_arena_freelist_insert (arena, segment);
			}
		}
	}

	/* cleanup hash table */
	if (arena->m_hash_table != arena->m_hash_table_0)
	{
		rtl_arena_free (
			gp_arena_arena,
			arena->m_hash_table, 
			arena->m_hash_size * sizeof(rtl_arena_segment_type*));

		arena->m_hash_table = arena->m_hash_table_0;
		arena->m_hash_size  = RTL_ARENA_HASH_SIZE;
		arena->m_hash_shift = highbit(arena->m_hash_size) - 1;
	}

	/* cleanup segment list */
	head = &(arena->m_segment_head);
	for (segment = head->m_snext; segment != head; segment = head->m_snext)
	{
		if (segment->m_type == RTL_ARENA_SEGMENT_TYPE_FREE)
		{
			/* remove from freelist */
			rtl_arena_freelist_remove (arena, segment);
		}
		else
		{
			/* can have only free and span segments here */
			OSL_ASSERT(segment->m_type == RTL_ARENA_SEGMENT_TYPE_SPAN);
		}

		/* remove from segment list */
		QUEUE_REMOVE_NAMED(segment, s);

		/* release segment descriptor */
		rtl_arena_segment_put (arena, &segment);
	}

	/* cleanup segment reserve list */
	head = &(arena->m_segment_reserve_head);
	for (segment = head->m_snext; segment != head; segment = head->m_snext)
	{
		/* remove from segment list */
		QUEUE_REMOVE_NAMED(segment, s);
	}

	/* cleanup segment reserve span(s) */
	head = &(arena->m_segment_reserve_span_head);
	for (segment = head->m_snext; segment != head; segment = head->m_snext)
	{
		/* can have only span segments here */
		OSL_ASSERT(segment->m_type == RTL_ARENA_SEGMENT_TYPE_SPAN);

		/* remove from segment list */
		QUEUE_REMOVE_NAMED(segment, s);

		/* return span to g_machdep_arena */
		rtl_machdep_free (gp_machdep_arena, (void*)(segment->m_addr), segment->m_size);
	}
}

/* ================================================================= *
 *
 * arena implementation.
 *
 * ================================================================= */

/** rtl_arena_create()
 */
rtl_arena_type *
SAL_CALL rtl_arena_create (
	const char *       name,
	sal_Size           quantum,
	sal_Size           quantum_cache_max,
	rtl_arena_type *   source_arena,
	void * (SAL_CALL * source_alloc)(rtl_arena_type *, sal_Size *),
	void   (SAL_CALL * source_free) (rtl_arena_type *, void *, sal_Size),
	int                flags
) SAL_THROW_EXTERN_C()
{
	rtl_arena_type * result = 0;
	sal_Size         size   = sizeof(rtl_arena_type);

    (void) flags; /* unused */

try_alloc:
	result = (rtl_arena_type*)rtl_arena_alloc (gp_arena_arena, &size);
	if (result != 0)
	{
		rtl_arena_type * arena = result;
		VALGRIND_CREATE_MEMPOOL(arena, 0, 0);
		rtl_arena_constructor (arena);

		if (!source_arena)
		{
			OSL_ASSERT(gp_default_arena != 0);
			source_arena = gp_default_arena;
		}

		result = rtl_arena_activate (
			arena,
			name,
			quantum,
			quantum_cache_max,
			source_arena,
			source_alloc,
			source_free
		);

		if (result == 0)
		{
			rtl_arena_deactivate (arena);
			rtl_arena_destructor (arena);
			VALGRIND_DESTROY_MEMPOOL(arena);
			rtl_arena_free (gp_arena_arena, arena, size);
		}
	}
	else if (gp_arena_arena == 0)
	{
		if (rtl_arena_init())
		{
			/* try again */
			goto try_alloc;
		}
	}
	return (result);
}

/** rtl_arena_destroy()
 */
void
SAL_CALL rtl_arena_destroy (
	rtl_arena_type * arena
) 
{
	if (arena != 0)
	{
		rtl_arena_deactivate (arena);
		rtl_arena_destructor (arena);
		VALGRIND_DESTROY_MEMPOOL(arena);
		rtl_arena_free (gp_arena_arena, arena, sizeof(rtl_arena_type));
	}
}

/** rtl_arena_alloc()
 */
void *
SAL_CALL rtl_arena_alloc (
	rtl_arena_type * arena,
	sal_Size *       pSize
) SAL_THROW_EXTERN_C()
{
	void * addr = 0;

	if ((arena != 0) && (pSize != 0))
	{
		sal_Size size = RTL_MEMORY_ALIGN((*pSize), arena->m_quantum);
		if (size > arena->m_qcache_max)
		{
			/* allocate from segment list */
			rtl_arena_segment_type *segment = 0;

			RTL_MEMORY_LOCK_ACQUIRE(&(arena->m_lock));
			if (rtl_arena_segment_alloc (arena, size, &segment) ||
				rtl_arena_segment_create(arena, size, &segment)    )
			{
				/* shrink to fit */
				sal_Size oversize;

				/* mark segment used */
				OSL_ASSERT(segment->m_type == RTL_ARENA_SEGMENT_TYPE_FREE);
				segment->m_type = RTL_ARENA_SEGMENT_TYPE_USED;

				/* resize */
				OSL_ASSERT(segment->m_size >= size);
				oversize = segment->m_size - size;
				if (oversize >= SAL_MAX(arena->m_quantum, arena->m_qcache_max))
				{
					rtl_arena_segment_type * remainder = 0;
					rtl_arena_segment_get (arena, &remainder);
					if (remainder != 0)
					{
						segment->m_size = size;

						remainder->m_addr = segment->m_addr + segment->m_size;
						remainder->m_size = oversize;
						remainder->m_type = RTL_ARENA_SEGMENT_TYPE_FREE;
						QUEUE_INSERT_HEAD_NAMED(segment, remainder, s);

						rtl_arena_freelist_insert (arena, remainder);
					}
				}

				rtl_arena_hash_insert (arena, segment);

                /* DEBUG ONLY: mark allocated, undefined */
				OSL_DEBUG_ONLY(memset((void*)(segment->m_addr), 0x77777777, segment->m_size));
				VALGRIND_MEMPOOL_ALLOC(arena, segment->m_addr, segment->m_size);

				(*pSize) = segment->m_size;
				addr = (void*)(segment->m_addr);
			}
			RTL_MEMORY_LOCK_RELEASE(&(arena->m_lock));
		}
		else if (size > 0)
		{
			/* allocate from quantum cache(s) */
			int index = (size >> arena->m_quantum_shift) - 1;
			OSL_ASSERT (arena->m_qcache_ptr[index] != 0);

			addr = rtl_cache_alloc (arena->m_qcache_ptr[index]);
			if (addr != 0)
				(*pSize) = size;
		}
	}
	return (addr);
}

/** rtl_arena_free()
 */
void
SAL_CALL rtl_arena_free (
	rtl_arena_type * arena,
	void *           addr,
	sal_Size         size
) SAL_THROW_EXTERN_C()
{
	if (arena != 0)
	{
		size = RTL_MEMORY_ALIGN(size, arena->m_quantum);
		if (size > arena->m_qcache_max)
		{
			/* free to segment list */
			rtl_arena_segment_type * segment;

			RTL_MEMORY_LOCK_ACQUIRE(&(arena->m_lock));

			segment = rtl_arena_hash_remove (arena, (sal_uIntPtr)(addr), size);
			if (segment != 0)
			{
				rtl_arena_segment_type *next, *prev;

				/* DEBUG ONLY: mark unallocated, undefined */
				VALGRIND_MEMPOOL_FREE(arena, segment->m_addr);
                /* OSL_DEBUG_ONLY() */ VALGRIND_MAKE_MEM_UNDEFINED(segment->m_addr, segment->m_size);
                OSL_DEBUG_ONLY(memset((void*)(segment->m_addr), 0x33333333, segment->m_size));

				/* coalesce w/ adjacent free segment(s) */
				rtl_arena_segment_coalesce (arena, segment);

				/* determine (new) next and prev segment */
				next = segment->m_snext, prev = segment->m_sprev;

				/* entire span free when prev is a span, and next is either a span or a list head */
				if (((prev->m_type == RTL_ARENA_SEGMENT_TYPE_SPAN)) &&
					((next->m_type == RTL_ARENA_SEGMENT_TYPE_SPAN)  ||
					 (next->m_type == RTL_ARENA_SEGMENT_TYPE_HEAD))    )
				{
					OSL_ASSERT((prev->m_addr == segment->m_addr) &&
							   (prev->m_size == segment->m_size)    );

					if (arena->m_source_free)
					{
						addr = (void*)(prev->m_addr);
						size = prev->m_size;

						/* remove from segment list */
						QUEUE_REMOVE_NAMED(segment, s);

						/* release segment descriptor */
						rtl_arena_segment_put (arena, &segment);

						/* remove from segment list */
						QUEUE_REMOVE_NAMED(prev, s);

						/* release (span) segment descriptor */
						rtl_arena_segment_put (arena, &prev);

						/* update stats, return span to source arena */
						arena->m_stats.m_mem_total -= size;
						RTL_MEMORY_LOCK_RELEASE(&(arena->m_lock));

						(arena->m_source_free)(arena->m_source_arena, addr, size);
						return;
					}
				}

				/* insert onto freelist */
				rtl_arena_freelist_insert (arena, segment);
			}

			RTL_MEMORY_LOCK_RELEASE(&(arena->m_lock));
		}
		else if (size > 0)
		{
			/* free to quantum cache(s) */
			int index = (size >> arena->m_quantum_shift) - 1;
			OSL_ASSERT (arena->m_qcache_ptr[index] != 0);

			rtl_cache_free (arena->m_qcache_ptr[index], addr);
		}
	}
}

/* ================================================================= *
 *
 * machdep internals.
 *
 * ================================================================= */

#if defined(SAL_UNX)
#include <sys/mman.h>
#elif defined(SAL_W32) || defined(SAL_OS2)
#define MAP_FAILED 0
#endif /* SAL_UNX || SAL_W32 */

/** rtl_machdep_alloc()
 */
static void *
SAL_CALL rtl_machdep_alloc (
	rtl_arena_type * pArena,
	sal_Size *       pSize
)
{
	void *   addr;
	sal_Size size = (*pSize);

	OSL_PRECOND(pArena == gp_machdep_arena, "rtl_machdep_alloc(): invalid argument");

#if defined(SOLARIS) && defined(SPARC)
	/* see @ mmap(2) man pages */
	size += (pArena->m_quantum + pArena->m_quantum); /* "red-zone" pages */
	if (size > (4 << 20))
		size = RTL_MEMORY_P2ROUNDUP(size, (4 << 20));
	else if (size > (512 << 10))
		size = RTL_MEMORY_P2ROUNDUP(size, (512 << 10));
	else
		size = RTL_MEMORY_P2ROUNDUP(size, (64 << 10));
	size -= (pArena->m_quantum + pArena->m_quantum); /* "red-zone" pages */
#else
	/* default allocation granularity */
	size = RTL_MEMORY_P2ROUNDUP(size, SAL_MAX(pArena->m_quantum, 64 << 10));
#endif

#if defined(SAL_UNX)
	addr = mmap (NULL, (size_t)(size), PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
#elif defined(SAL_W32)
	addr = VirtualAlloc (NULL, (SIZE_T)(size), MEM_COMMIT, PAGE_READWRITE);
#elif defined(SAL_OS2)
	/* Use valloc() to use libc 16MB chunks when allocating high memory, to reduce
	   virtual address fragmentation. */
	addr = valloc( size);
#endif /* (SAL_UNX || SAL_W32 || SAL_OS2) */

	if (addr != MAP_FAILED)
	{
		pArena->m_stats.m_alloc += 1;
		pArena->m_stats.m_mem_total += size;
		pArena->m_stats.m_mem_alloc += size;

		(*pSize) = size;
		return (addr);
	}
	return (NULL);
}

/** rtl_machdep_free()
 */
static void
SAL_CALL rtl_machdep_free (
	rtl_arena_type * pArena,
	void *           pAddr,
	sal_Size         nSize
)
{
	OSL_PRECOND(pArena == gp_machdep_arena, "rtl_machdep_free(): invalid argument");

	pArena->m_stats.m_free += 1;
	pArena->m_stats.m_mem_total -= nSize;
	pArena->m_stats.m_mem_alloc -= nSize;

#if defined(SAL_UNX)
	(void) munmap(pAddr, nSize);
#elif defined(SAL_W32)
	(void) VirtualFree ((LPVOID)(pAddr), (SIZE_T)(0), MEM_RELEASE);
#elif defined(SAL_OS2)
	free(pAddr);
#endif /* (SAL_UNX || SAL_W32) */
}

/** rtl_machdep_pagesize()
 */
static sal_Size
rtl_machdep_pagesize (void)
{
#if defined(SAL_UNX)
#if defined(FREEBSD) || defined(NETBSD)
	return ((sal_Size)getpagesize());
#else  /* POSIX */
	return ((sal_Size)sysconf(_SC_PAGESIZE));
#endif /* xBSD || POSIX */
#elif defined(SAL_W32)
	SYSTEM_INFO info;
	GetSystemInfo (&info);
	return ((sal_Size)(info.dwPageSize));
#elif defined(SAL_OS2)
	ULONG ulPageSize;
	DosQuerySysInfo(QSV_PAGE_SIZE, QSV_PAGE_SIZE, &ulPageSize, sizeof(ULONG));
	return ((sal_Size)ulPageSize);
#endif /* (SAL_UNX || SAL_W32) */
}

/* ================================================================= *
 *
 * arena initialization.
 *
 * ================================================================= */

static void
rtl_arena_once_init (void)
{
	{
		/* list of arenas */
		RTL_MEMORY_LOCK_INIT(&(g_arena_list.m_lock));
		rtl_arena_constructor (&(g_arena_list.m_arena_head));
	}
	{
		/* machdep (pseudo) arena */
		static rtl_arena_type g_machdep_arena;

		OSL_ASSERT(gp_machdep_arena == 0);
		VALGRIND_CREATE_MEMPOOL(&g_machdep_arena, 0, 0);
		rtl_arena_constructor (&g_machdep_arena);

		gp_machdep_arena = rtl_arena_activate (
			&g_machdep_arena,
			"rtl_machdep_arena",
			rtl_machdep_pagesize(),
			0,       /* no quantum caching */
			0, 0, 0  /* no source */
		);
		OSL_ASSERT(gp_machdep_arena != 0);
	}
	{
		/* default arena */
		static rtl_arena_type g_default_arena;

		OSL_ASSERT(gp_default_arena == 0);
		VALGRIND_CREATE_MEMPOOL(&g_default_arena, 0, 0);
		rtl_arena_constructor (&g_default_arena);

		gp_default_arena = rtl_arena_activate (
			&g_default_arena,
			"rtl_default_arena",
			rtl_machdep_pagesize(),
			0,                 /* no quantum caching */
			gp_machdep_arena,  /* source */
			rtl_machdep_alloc,
			rtl_machdep_free
		);
		OSL_ASSERT(gp_default_arena != 0);
	}
	{
		/* arena internal arena */
		static rtl_arena_type g_arena_arena;

		OSL_ASSERT(gp_arena_arena == 0);
		VALGRIND_CREATE_MEMPOOL(&g_arena_arena, 0, 0);
		rtl_arena_constructor (&g_arena_arena);

		gp_arena_arena = rtl_arena_activate (
			&g_arena_arena,
			"rtl_arena_internal_arena",
			64,                /* quantum */
			0,                 /* no quantum caching */
			gp_default_arena,  /* source */
			rtl_arena_alloc,
			rtl_arena_free
		);
		OSL_ASSERT(gp_arena_arena != 0);
	}
}

static int
rtl_arena_init (void)
{
	static sal_once_type g_once = SAL_ONCE_INIT;
	SAL_ONCE(&g_once, rtl_arena_once_init);
	return (gp_arena_arena != 0);
}

/* ================================================================= */

/*
  Issue http://udk.openoffice.org/issues/show_bug.cgi?id=92388

  Mac OS X does not seem to support "__cxa__atexit", thus leading
  to the situation that "__attribute__((destructor))__" functions
  (in particular "rtl_{memory|cache|arena}_fini") become called
  _before_ global C++ object d'tors.

  Delegated the call to "rtl_arena_fini()" into a dummy C++ object,
  see alloc_fini.cxx .
*/
#if defined(__GNUC__) && !defined(MACOSX)
static void rtl_arena_fini (void) __attribute__((destructor));
#elif defined(__SUNPRO_C) || defined(__SUNPRO_CC)
#pragma fini(rtl_arena_fini)
static void rtl_arena_fini (void);
#endif /* __GNUC__ || __SUNPRO_C */

void
rtl_arena_fini (void)
{
	if (gp_arena_arena != 0)
	{
		rtl_arena_type * arena, * head;

		RTL_MEMORY_LOCK_ACQUIRE(&(g_arena_list.m_lock));
		head = &(g_arena_list.m_arena_head);

		for (arena = head->m_arena_next; arena != head; arena = arena->m_arena_next)
		{
			OSL_TRACE(
				"rtl_arena_fini(\"%s\"): "
				"allocs: %"PRIu64", frees: %"PRIu64"; total: %lu, used: %lu",
				arena->m_name,
				arena->m_stats.m_alloc, arena->m_stats.m_free,
				arena->m_stats.m_mem_total, arena->m_stats.m_mem_alloc
			);
		}
		RTL_MEMORY_LOCK_RELEASE(&(g_arena_list.m_lock));
	}
}

/* ================================================================= */