/*
 * heap_create.c
 */
#include "private.h"
#include "context.h"

/*--------------------------------------------------------- */
static int lub_heap_block_compare(const void *clientnode, const void *clientkey)
{
	int delta;
	const lub_heap_free_block_t *block = clientnode;
	const lub_heap_key_t *key = clientkey;

	delta = (block->tag.words - key->words);
	if (0 == delta) {
		/* if same size differentiate by address */
		delta = (block - key->block);
	}
	return delta;
}

/*--------------------------------------------------------- */
lub_heap_t *lub_heap_create(void *start, size_t size)
{
	lub_heap_t *this = NULL;

	/* we must have at least 1024 bytes for a heap */
	if (size > (sizeof(lub_heap_t) + 4)) {
		this = start;
		/* set up the binary tree for the free blocks */
		lub_bintree_init(&this->free_tree,
				 offsetof(lub_heap_free_block_t, bt_node),
				 lub_heap_block_compare, lub_heap_block_getkey);

		this->cache = 0;
		this->suppress = 0;

		/* initialise the statistics */
		this->stats.segs = 0;
		this->stats.segs_bytes = 0;
		this->stats.segs_overhead = 0;
		this->stats.free_blocks = 0;
		this->stats.free_bytes = 0;
		this->stats.free_overhead = 0;
		this->stats.static_blocks = 0;
		this->stats.static_bytes = 0;
		this->stats.static_overhead = 0;
		this->stats.alloc_blocks = 0;
		this->stats.alloc_bytes = 0;
		this->stats.alloc_overhead = 0;
		this->stats.alloc_hightide_blocks = 0;
		this->stats.alloc_hightide_bytes = 0;
		this->stats.alloc_hightide_overhead = 0;
		this->stats.free_hightide_blocks = 0;
		this->stats.free_hightide_bytes = 0;
		this->stats.free_hightide_overhead = 0;
		this->stats.alloc_total_blocks = 0;
		this->stats.alloc_total_bytes = 0;

		/* initialise the first segment */
		this->first_segment.next = NULL;

		/* create the default segment */
		lub_heap_add_segment(this,
				     &this->first_segment,
				     size - sizeof(lub_heap_t) +
				     sizeof(lub_heap_segment_t));

		this->stats.segs_overhead += sizeof(lub_heap_t);

		/* add this heap to the linked list of heaps in the system */
		{
			lub_heap_leak_t *leak = lub_heap_leak_instance();
			this->next = leak->m_heap_list;
			leak->m_heap_list = this;
			lub_heap_leak_release(leak);
		}
	}
	return this;
}

/*--------------------------------------------------------- */