obj40.c

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	/* Prepapre the StatData hint. */
	aal_memset(&stat, 0, sizeof(stat));
	
	if ((res = obj40_stat_unix_init(&stat, &unixh, bytes, rdev)))
		return res;
	
	if ((res = obj40_stat_lw_init(obj, &stat, &lwh, size, nlink, mode)))
		return res;

	if ((res = obj40_stat_plug_init(obj, &stat, &plugh)))
		return res;
	
	if ((res = obj40_stat_heir_init(obj, &stat, &heirh)))
		return res;
	
	if ((res = obj40_stat_sym_init(obj, &stat, str)))
		return res;

	if ((res = obj40_stat_crc_init(obj, &stat, &crch, str)))
		return res;
	
	hint.specific = &stat;

	/* Lookup place new item to be insert at and insert it to tree */
	switch ((lookup = obj40_find_item(obj, &hint.offset, FIND_CONV, 
					  NULL, NULL, STAT_PLACE(obj))))
	{
	case ABSENT:
		break;
	default:
		return lookup < 0 ? lookup : -EIO;
	}
	
	/* Insert stat data to tree */
	res = obj40_insert(obj, STAT_PLACE(obj), &hint, LEAF_LEVEL);
	
	/* Reset file. */
	if (reiser4_psobj(obj)->reset)
		reiser4_psobj(obj)->reset(obj);

	return res < 0 ? res : 0;
}

errno_t obj40_create(reiser4_object_t *obj, object_hint_t *hint) {
	if (hint == NULL)
		return obj40_create_stat(obj, 0, 0, 0, 0, 0, NULL);
	
	return obj40_create_stat(obj, 0, 0, hint->rdev, 0, 
				 hint->mode, hint->str);
}

/* Writes one stat data extension. */
errno_t obj40_write_ext(reiser4_object_t *obj, rid_t id, void *data) {
	stat_hint_t stat;

	aal_memset(&stat, 0, sizeof(stat));

	stat.extmask |= (1 << id);
	if (data) stat.ext[id] = data;

	return obj40_save_stat(obj, &stat);
}

/* Returns extensions mask from stat data item at @place. */
uint64_t obj40_extmask(reiser4_place_t *place) {
	trans_hint_t hint;
	stat_hint_t stat;

	aal_memset(&stat, 0, sizeof(stat));

	/* Preparing hint and mask */
	hint.specific = &stat;
	hint.place_func = NULL;
	hint.region_func = NULL;
	hint.shift_flags = SF_DEFAULT;
	
	/* Calling statdata open method if any */
	if (objcall(place, object->fetch_units, &hint) != 1)
		return MAX_UINT64;
	
	return stat.extmask;
}

/* Updates size field in the stat data */
errno_t obj40_set_size(reiser4_object_t *obj, uint64_t size) {
	sdhint_lw_t lwh;
	errno_t res;

	if ((res = obj40_read_ext(obj, SDEXT_LW_ID, &lwh)))
		return res;

	lwh.size = size;
	
	return obj40_write_ext(obj, SDEXT_LW_ID, &lwh);
}

/* Gets nlink field from the stat data */
int64_t obj40_get_nlink(reiser4_object_t *obj, int update) {
	sdhint_lw_t lwh;
	errno_t res;

	if (update) {
		if ((res = obj40_update(obj)))
			return res;
	}
	
	if ((res = obj40_read_ext(obj, SDEXT_LW_ID, &lwh)))
		return res;
	
	return lwh.nlink;
}

/* Updates nlink field in the stat data */
errno_t obj40_set_nlink(reiser4_object_t *obj, uint32_t nlink) {
	sdhint_lw_t lwh;
	errno_t res;

	if ((res = obj40_read_ext(obj, SDEXT_LW_ID, &lwh)))
		return res;

	lwh.nlink = nlink;
	
	return obj40_write_ext(obj, SDEXT_LW_ID, &lwh);
}

/* Gets bytes field from the stat data */
uint64_t obj40_get_bytes(reiser4_object_t *obj) {
	sdhint_unix_t unixh;

	if (obj40_read_ext(obj, SDEXT_UNIX_ID, &unixh))
		return 0;
	
	return unixh.bytes;
}

/* Updates bytes field in the stat data */
errno_t obj40_set_bytes(reiser4_object_t *obj, uint64_t bytes) {
	sdhint_unix_t unixh;
	errno_t res;

	if ((res = obj40_read_ext(obj, SDEXT_UNIX_ID, &unixh)))
		return res;

	unixh.rdev = 0;
	unixh.bytes = bytes;
	
	return obj40_write_ext(obj, SDEXT_UNIX_ID, &unixh);
}

/* Changes nlink field in statdata by passed @value */
static errno_t obj40_inc_link(reiser4_object_t *obj, 
			      int32_t value, int update)
{
	uint32_t nlink = obj40_get_nlink(obj, update);
	return obj40_set_nlink(obj, nlink + value);
}

/* Removes object stat data. */
errno_t obj40_clobber(reiser4_object_t *obj) {
	errno_t res;
	trans_hint_t hint;
	
	aal_assert("umka-2546", obj != NULL);

	if ((res = obj40_update(obj)))
		return res;

	aal_memset(&hint, 0, sizeof(hint));
	hint.count = 1;
	hint.shift_flags = SF_DEFAULT;
	STAT_PLACE(obj)->pos.unit = MAX_UINT32;
	
	return obj40_remove(obj, STAT_PLACE(obj), &hint);
}

/* Enumerates object metadata. */
errno_t obj40_metadata(reiser4_object_t *obj, 
		       place_func_t place_func,
		       void *data)
{
	errno_t res;
	
	aal_assert("umka-2549", obj != NULL);
	aal_assert("umka-2550", place_func != NULL);

	if ((res = obj40_update(obj)))
		return res;

	return place_func(STAT_PLACE(obj), data);
}

errno_t obj40_link(reiser4_object_t *obj) {
	return obj40_inc_link(obj, 1, 1);
}

errno_t obj40_unlink(reiser4_object_t *obj) {
	return obj40_inc_link(obj, -1, 1);
}

/* Check if linked. Needed to let higher API levels know, that file has
   zero links and may be clobbered. */
bool_t obj40_linked(reiser4_object_t *entity) {
	return obj40_get_nlink(entity, 1) != 0;
}
#endif

/* Makes sure, that passed place points to right location in tree by means of
   calling tree_lookup() for its key. This is needed, because items may move to
   somewhere after each balancing. */
errno_t obj40_update(reiser4_object_t *obj) {
	lookup_t res;
	
	aal_assert("umka-1905", obj != NULL);
		
	/* Looking for stat data place by */
	switch ((res = obj40_find_item(obj, &obj->info.object,
				       FIND_EXACT, NULL, NULL,
				       STAT_PLACE(obj))))
	{
	case PRESENT:
		return 0;
	case ABSENT:
		return -EIO;
	default:
		return res;
	}
}

/* Reads data from the tree to passed @hint. */
int64_t obj40_read(reiser4_object_t *obj, trans_hint_t *hint, 
		   void *buff, uint64_t off, uint64_t count)
{	
	/* Preparing hint to be used for calling read with it. Here we
	   initialize @count -- number of bytes to read, @specific -- pointer to
	   buffer data will be read into, and pointer to tree instance, file is
	   opened on. */ 
	aal_memset(hint, 0, sizeof(*hint));
	
	/* Initializing offset data must be read from. This is current file
	   offset, so we use @reg->position. */
	aal_memcpy(&hint->offset, &obj->position, sizeof(hint->offset));
	objcall(&hint->offset, set_offset, off);
	
	hint->count = count;
	hint->specific = buff;
	
	return obj40_core->flow_ops.read(obj->info.tree, hint);
}

#ifndef ENABLE_MINIMAL
int64_t obj40_convert(reiser4_object_t *obj, conv_hint_t *hint) {
	return obj40_core->flow_ops.convert(obj->info.tree, hint);
}

int64_t obj40_cut(reiser4_object_t *obj, trans_hint_t *hint, 
		  uint64_t off, uint64_t count,
		  region_func_t func, 
		  void *data)
{
	aal_memset(hint, 0, sizeof(*hint));
		
	/* Preparing key of the data to be cut. */
	aal_memcpy(&hint->offset, &obj->position, sizeof(hint->offset));
	objcall(&hint->offset, set_offset, off);

	/* Removing data from the tree. */
	hint->count = count;
	hint->shift_flags = SF_DEFAULT;
	hint->region_func = func;
	hint->data = data;
	
	return obj40_core->flow_ops.cut(obj->info.tree, hint);
}

/* Truncates data in tree */
int64_t obj40_truncate(reiser4_object_t *obj, uint64_t n,
		       reiser4_item_plug_t *item_plug)
{
	trans_hint_t hint;
	uint64_t size;
	uint64_t bytes;
	errno_t res;
	
	aal_assert("vpf-1882", obj != NULL);
	aal_assert("vpf-1884", item_plug != NULL);
	
	if ((res = obj40_update(obj)))
		return res;
	
	size = obj40_get_size(obj);
	
	if (size == n)
		return 0;
	
	if (n > size) {
		if ((res = obj40_write(obj, &hint, NULL, size, n - size, 
				       item_plug, NULL, NULL)) < 0)
		{
			return res;
		}
		
		bytes = hint.bytes;
	} else {
		res = obj40_cut(obj, &hint, n, MAX_UINT64, NULL, NULL);
		if (res < 0) return res;

		bytes = -hint.bytes;
	}
	
	/* Updating stat data fields. */
	return obj40_touch(obj, n - size, bytes);
}

/* Inserts passed item hint into the tree. After function is finished, place
   contains the place of the inserted item. */
int64_t obj40_insert(reiser4_object_t *obj, 
		     reiser4_place_t *place,
		     trans_hint_t *hint, 
		     uint8_t level)
{
	return obj40_core->tree_ops.insert(obj->info.tree,
					   place, hint, level);
}

/* Removes item/unit by @key */
errno_t obj40_remove(reiser4_object_t *obj, 
		     reiser4_place_t *place,
		     trans_hint_t *trans)
{
	return obj40_core->tree_ops.remove(obj->info.tree,
					   place, trans);
}

/* This fucntion implements object item enumerator function. 
   Used for getting directory metadata on packing, etc. */
errno_t obj40_traverse(reiser4_object_t *obj, 
		       place_func_t place_func, 
		       obj_func_t obj_func,
		       void *data)
{
	errno_t res;
	
	aal_assert("umka-1712", obj != NULL);
	aal_assert("umka-1713", place_func != NULL);
	
	/* Calculating stat data item. */
	if ((res = obj40_metadata(obj, place_func, data)))
		return res;

	/* Update current body item coord. */
	if ((res = obj40_update_body(obj, obj_func)) != PRESENT)
		return res == ABSENT ? 0 : res;

	/* Loop until all items are enumerated. */
	while (1) {
		/* Calling callback function. */
		if ((res = place_func(&obj->body, data)))
			return res;

		/* Getting next item. */
		if ((res = obj40_next_item(obj)) < 0)
			return res;
		
		if (res == ABSENT)
			return 0;
	}

	return 0;
}

/* File data enumeration related stuff. */
typedef struct layout_hint {
	void *data;
	region_func_t region_func;
} layout_hint_t;

static errno_t cb_item_layout(blk_t start, count_t width, void *data) {
	layout_hint_t *hint = (layout_hint_t *)data;
	return hint->region_func(start, width, hint->data);
}

/* This fucntion implements hashed directory enumerator function.
   It is used when calculating fargmentation, prining. */
errno_t obj40_layout(reiser4_object_t *obj,
		     region_func_t region_func,
		     obj_func_t obj_func,
		     void *data)
{
	layout_hint_t hint;
	errno_t res;

	aal_assert("umka-1473", obj != NULL);
	aal_assert("umka-1474", region_func != NULL);
	
	/* Update current body item coord. */
	if ((res = obj40_update_body(obj, obj_func)) != PRESENT)
		return res == ABSENT ? 0 : res;

	/* Prepare layout hint. */
	hint.data = data;
	hint.region_func = region_func;

	/* Loop until all items are enumerated. */
	while (1) {
		reiser4_place_t *place = &obj->body;
		
		if (obj->body.plug->object->layout) {
			/* Calling item's layout method */
			if ((res = objcall(place, object->layout, 
					   cb_item_layout, &hint)))
			{
				return res;
			}
		} else {
			/* Layout method is not implemented. Counting item
			   itself. */
			blk_t blk = place_blknr(place);
			
			if ((res = cb_item_layout(blk, 1, &hint)))
				return res;
		}

		/* Getting next item. */
		if ((res = obj40_next_item(obj)) < 0)
			return res;

		/* Object is over? */
		if (res == ABSENT)
			return 0;
	}
	
	return 0;
}

/* Writes passed data to the file. Returns amount of written bytes. */
int64_t obj40_write(reiser4_object_t *obj, trans_hint_t *hint, 
		    void *buff, uint64_t off, uint64_t count, 
		    reiser4_item_plug_t *item_plug, 
		    place_func_t func, void *data)
{
	/* Preparing hint to be used for calling write method. This is
	   initializing @count - number of bytes to write, @specific - buffer to
	   write into and @offset -- file offset data must be written at. */
	aal_memset(hint, 0, sizeof(*hint));
	hint->count = count;
	
	hint->specific = buff;
	hint->shift_flags = SF_DEFAULT;
	hint->place_func = func;
	hint->plug = item_plug;
	hint->data = data;
	
	aal_memcpy(&hint->offset, &obj->position, sizeof(hint->offset));
	objcall(&hint->offset, set_offset, off);
	
	/* Write data to tree. */
	return obj40_core->flow_ops.write(obj->info.tree, hint);
}

errno_t obj40_touch(reiser4_object_t *obj, int64_t size, int64_t bytes) {
	uint64_t fbytes;
	uint64_t fsize;
	errno_t res;
	
	/* Updating the SD place and update size, bytes there. */
	if ((res = obj40_update(obj)))
		return res;
	
	fsize = obj40_get_size(obj);
	fbytes = obj40_get_bytes(obj);

	/* Update size & bytes unless they do not change. */
	if (size && (res = obj40_set_size(obj, fsize + size)))
		return res;

	if (bytes && (res = obj40_set_bytes(obj, fbytes + bytes)))
		return res;
	
	return 0;
}
#endif