obj40.c

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/* Copyright (C) 2001-2005 by Hans Reiser, licensing governed by
   reiser4progs/COPYING.
   
   obj40.c -- reiser4 file 40 plugins common code. */

#include "obj40.h"

reiser4_core_t *obj40_core = NULL;

/* Initializing instance in the common way, reseting directory. */
errno_t obj40_open(reiser4_object_t *obj) {
	aal_assert("vpf-1827", obj != NULL);
	aal_assert("vpf-1826", obj->info.tree != NULL);
	aal_assert("vpf-1828", 
		   reiser4_psobj(obj)->p.id.type == OBJECT_PLUG_TYPE);
	
	if (obj->info.start.plug->p.id.group != STAT_ITEM)
		return -EIO;
	
	/* Positioning to the first directory unit. */
	if (reiser4_psobj(obj)->reset)
		reiser4_psobj(obj)->reset(obj);
	
	return 0;
}

/* Set the file position offset to the given @offset. */
errno_t obj40_seek(reiser4_object_t *obj, uint64_t offset) {
	aal_assert("umka-1968", obj != NULL);

	objcall(&obj->position, set_offset, offset);
	
	return 0;
}

/* Resets file position. The file position is stored inside @obj->position,
   so it just builds new zero offset key.*/
errno_t obj40_reset(reiser4_object_t *obj) {
	aal_assert("umka-1963", obj != NULL);
	
	plugcall(obj->info.object.plug, build_generic,
		 &obj->position, KEY_FILEBODY_TYPE, 
		 objcall(&obj->info.object, get_locality),
		 objcall(&obj->info.object, get_ordering),
		 objcall(&obj->info.object, get_objectid), 0);

	return 0;
}

/* Fetches item info at @place. */
errno_t obj40_fetch_item(reiser4_place_t *place) {
	return objcall(place->node, fetch, &place->pos, place);
}

/* Checks if @place has valid position. */
bool_t obj40_valid_item(reiser4_place_t *place) {
	uint32_t items = objcall(place->node, items);
	return (place->pos.item < items);
}

/* Checks if passed @place belongs to some object by the short @key. */
lookup_t obj40_belong(reiser4_place_t *place, reiser4_key_t *key) {
	errno_t res;
	
	/* If there is no valid node, it does defenetely not belong to 
	   the object. */
	if (!place->node)
		return ABSENT;
	
	/* Checking if item component in @place->pos is valid one. This is
	   needed because tree_lookup() does not fetch item data at place if it
	   was not found. So, it may point to unexistent item and we should
	   check this here. */
	if (!obj40_valid_item(place))
		return ABSENT;

	/* Fetching item info at @place. This is needed to make sue, that 
	   all @place fields are initialized rigth. Normally it is done by
	   tree_lookup(), if it is sure, that place points to valid postion 
	   in node. This happen if lookup found a key. Otherwise it leaves 
	   place not initialized and caller has to care about it. */
	if ((res = obj40_fetch_item(place)))
		return res;
	
	/* Is the place of the same object? */
	return objcall(key, compshort, &place->key) ? ABSENT : PRESENT;
}

/* Performs lookup and returns result to caller */
lookup_t obj40_find_item(reiser4_object_t *obj, reiser4_key_t *key, 
			 lookup_bias_t bias, coll_func_t func, 
			 coll_hint_t *chint, reiser4_place_t *place)
{
	lookup_hint_t hint;
	
	aal_assert("umka-1966", obj != NULL);
	aal_assert("umka-3111", key != NULL);
	aal_assert("umka-3112", place != NULL);

	hint.key = key;
	hint.level = LEAF_LEVEL;
	
#ifndef ENABLE_MINIMAL
	hint.hint = chint;
	hint.collision = func;
#endif
	
	return obj40_core->tree_ops.lookup(obj->info.tree,
					   &hint, bias, place);
}

/* Takes the next item, perform some checks if it is of the same object. */
lookup_t obj40_next_item(reiser4_object_t *obj) {
	reiser4_place_t place;
	lookup_t res;

	aal_assert("vpf-1833", obj != NULL);

	/* Getting next item into the @place. */
	if ((res = obj40_core->tree_ops.next_item(obj->info.tree,
						  &obj->body, &place)))
	{
		return res;
	}

	/* Check if this item owned by this object. */
	if (obj40_belong(&place, &obj->position) == ABSENT)
		return ABSENT;
	
	/* If @place belongs to the object, copy it to the object body. */
	aal_memcpy(&obj->body, &place, sizeof(place));
	
	/* Correcting unit pos for next body item. */
	if (obj->body.pos.unit == MAX_UINT32)
		obj->body.pos.unit = 0;

	return PRESENT;
}

lookup_t obj40_update_body(reiser4_object_t *obj, obj_func_t adjust_func) {
	uint32_t units;
	errno_t res;

#ifndef ENABLE_MINIMAL
	uint32_t adjust = obj->position.adjust;
#endif
	
	aal_assert("vpf-1344", obj != NULL);
	
	/* Lookup the current object position in the tree. */
	if ((res = obj40_find_item(obj, &obj->position, FIND_EXACT, 
				   NULL, NULL, &obj->body)) < 0)
	{
		return res;
	}
	
	if (res == ABSENT) {
		/* Getting next object item if not valid place & just 
		   check if the current is ours if a valid one. */
		if (!obj40_valid_item(&obj->body)) {
			res = obj40_next_item(obj);
		} else {
			res = obj40_belong(&obj->body, &obj->position);
		}
		
		if (res != PRESENT)
			return res;

#ifndef ENABLE_MINIMAL
		/* No adjusting for the ABSENT result. */
		adjust = 0;
#endif
	}
	
	units = objcall(&obj->body, balance->units);
	
	/* Correcting unit pos for next body item. */
	if (obj->body.pos.unit == MAX_UINT32)
		obj->body.pos.unit = 0;

	/* Adjusting current position by key's adjust. This is needed
	   for working fine when a key collision takes place. */
	while (
#ifndef ENABLE_MINIMAL
	       adjust || 
#endif
	       obj->body.pos.unit >= units) 
	{

		if (obj->body.pos.unit >= units) {
			if ((res = obj40_next_item(obj)) != PRESENT)
				return res;
			
			units = objcall(&obj->body, balance->units);
			continue;
		}
		
#ifndef ENABLE_MINIMAL
		if (adjust) {
			if ((res = adjust_func(obj, NULL)) < 0)
				return res;
			
			if (res) return PRESENT;
			
			adjust--;
		}
#endif		
		obj->body.pos.unit++;
	}
	
	return PRESENT;
}

/* Reads one stat data extension to @data. */
errno_t obj40_read_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_load_stat(obj, &stat);
}

/* Gets size field from the stat data */
uint64_t obj40_get_size(reiser4_object_t *obj) {
	sdhint_lw_t lwh;

	if (obj40_read_ext(obj, SDEXT_LW_ID, &lwh))
		return MAX_UINT64;
	
	return lwh.size;
}

/* Loads stat data to passed @hint. */
errno_t obj40_load_stat(reiser4_object_t *obj, stat_hint_t *hint) {
	trans_hint_t trans;

	aal_assert("umka-2553", obj != NULL);

	/* Preparing hint and mask. */
	trans.specific = hint;
	trans.place_func = NULL;
	trans.region_func = NULL;
	trans.shift_flags = SF_DEFAULT;
	
	/* Calling statdata fetch method. */
	if (objcall(STAT_PLACE(obj), object->fetch_units, &trans) != 1)
		return -EIO;
	
	return 0;
}

#ifndef ENABLE_MINIMAL
/* Saves stat data to passed @hint. */
errno_t obj40_save_stat(reiser4_object_t *obj, stat_hint_t *hint) {
	trans_hint_t trans;
	
	aal_assert("umka-2554", obj != NULL);

	/* Preparing hint and mask */
	trans.specific = hint;
	trans.place_func = NULL;
	trans.region_func = NULL;
	trans.shift_flags = SF_DEFAULT;

	/* Updating stat data. */
	if (objcall(STAT_PLACE(obj), object->update_units, &trans) <= 0)
		return -EIO;
	
	return 0;
}

errno_t obj40_inherit(object_info_t *info, object_info_t *parent) {
	int i;
	
	aal_assert("vpf-1855", info != NULL);
	aal_assert("vpf-1855", info->pset.plug[PSET_OBJ] != NULL);
	aal_assert("vpf-1855", parent != NULL);
	
	info->pset.plug_mask |= (1 << PSET_OBJ);
	
	/* Get not specified plugins from the parent. Do not set flags into 
	   plug_mask as these plugins are inherited but not specified 
	   explicitly. */
	for (i = 0; i < PSET_LAST; i++) {
		if (info->pset.plug_mask & (1 << i))
			continue;

		info->pset.plug[i] = parent->pset.plug[i];
	}

	return 0;
}

/* Prepapre unix hint in StatData */
errno_t obj40_stat_unix_init(stat_hint_t *stat, sdhint_unix_t *unixh, 
			     uint64_t bytes, uint64_t rdev) 
{
	aal_assert("vpf-1772", stat != NULL);
	aal_assert("vpf-1773", unixh != NULL);

	/* Unix extension hint initializing */
	if (rdev && bytes) {
		aal_error("Invalid stat data params (rdev or bytes).");
		return -EINVAL;
	} else {
		unixh->rdev = rdev;
		unixh->bytes = bytes;
	}

	unixh->uid = getuid();
	unixh->gid = getgid();
	
	unixh->atime = time(NULL);
	unixh->mtime = unixh->atime;
	unixh->ctime = unixh->atime;

	stat->extmask |= (1 << SDEXT_UNIX_ID);
	stat->ext[SDEXT_UNIX_ID] = unixh;
	
	return 0;
}

errno_t obj40_stat_lw_init(reiser4_object_t *obj, 
			   stat_hint_t *stat, 
			   sdhint_lw_t *lwh, 
			   uint64_t size,  
			   uint32_t nlink, 
			   uint16_t mode)
{
	aal_assert("vpf-1848", obj != NULL);
	aal_assert("vpf-1774", stat != NULL);
	aal_assert("vpf-1775", lwh != NULL);

	/* Light weight hint initializing. */
	lwh->size = size;
	lwh->nlink = nlink;

	/* mode is the bitwise OR between the given mode, the file type mode 
	   and the defaul rwx permissions. The later is 0755 for directories 
	   and 0644 for others. */
	mode |= reiser4_psobj(obj)->p.id.group == REG_OBJECT ? S_IFREG : 
		reiser4_psobj(obj)->p.id.group == DIR_OBJECT ? S_IFDIR : 
		reiser4_psobj(obj)->p.id.group == SYM_OBJECT ? S_IFLNK :
		0;
	
	if (reiser4_psobj(obj)->p.id.group == DIR_OBJECT)
		mode |= 0755;
	else
		mode |= 0644;

	
	lwh->mode = mode;
	
	stat->extmask |= (1 << SDEXT_LW_ID);
	stat->ext[SDEXT_LW_ID] = lwh;

	return 0;
}

static errno_t obj40_stat_plug_init(reiser4_object_t *obj, 
				    stat_hint_t *stat, 
				    sdhint_plug_t *plugh) 
{
	aal_assert("vpf-1777", stat != NULL);
	aal_assert("vpf-1776", plugh != NULL);
	aal_assert("vpf-1778", obj != NULL);

	/* Get plugins that must exists in the PLUGID extention. */
	obj->info.pset.plug_mask = 
		obj40_core->pset_ops.build_mask(obj->info.tree,
						&obj->info.pset);
	
	if (obj->info.pset.plug_mask) {
		aal_memcpy(plugh, &obj->info.pset, sizeof(*plugh));
		stat->extmask |= (1 << SDEXT_PSET_ID);
		stat->ext[SDEXT_PSET_ID] = plugh;
	}

	return 0;
}

static errno_t obj40_stat_heir_init(reiser4_object_t *obj, 
				    stat_hint_t *stat, 
				    sdhint_plug_t *heirh)
{
	aal_assert("vpf-1899", stat != NULL);
	aal_assert("vpf-1898", heirh != NULL);
	aal_assert("vpf-1897", obj != NULL);

	if (obj->info.hset.plug_mask) {
		aal_memcpy(heirh, &obj->info.hset, sizeof(*heirh));
		stat->extmask |= (1 << SDEXT_HSET_ID);
		stat->ext[SDEXT_HSET_ID] = heirh;
	}
	
	return 0;
}

static errno_t obj40_stat_sym_init(reiser4_object_t *obj, 
				   stat_hint_t *stat, 
				   char *path)
{
	aal_assert("vpf-1851", obj != NULL);
	aal_assert("vpf-1779", stat != NULL);
	
	if (reiser4_psobj(obj)->p.id.group != SYM_OBJECT)
		return 0;
	
	if (!path || !aal_strlen(path)) {
		aal_error("No SymLink target point is given.");
		return -EINVAL;
	}
	
	stat->extmask |= (1 << SDEXT_SYMLINK_ID);
	stat->ext[SDEXT_SYMLINK_ID] = path;
	
	return 0;
}

static errno_t obj40_stat_crc_init(reiser4_object_t *obj, 
				   stat_hint_t *stat,
				   sdhint_crypto_t *crch,
				   char *key) 
{
	aal_assert("vpf-1847", obj  != NULL);
	aal_assert("vpf-1780", stat != NULL);

	/* Plugin must be of the regular file group. */
	if (reiser4_psobj(obj)->p.id.group != REG_OBJECT)
		return 0;
	
	/* Check if cryto is specified. */
	if (reiser4_pscrypto(obj) != CRYPTO_NONE_ID) {
		if (!key || !aal_strlen(key)) {
			aal_error("No proper key is given: %s.", key);
			return -EINVAL;
		}
		
		stat->extmask |= (1 << SDEXT_CRYPTO_ID);
		stat->ext[SDEXT_CRYPTO_ID] = crch;

		crch->keylen = aal_strlen(key);
		/* To get the fingerprint digest plugin is needed. */
		aal_error("Crypto files cannot be created yet.");
		return -EINVAL;
	}
	
	return 0;
}

/* Create stat data item basing on passed extensions @mask, @size, @bytes,
   @nlinks, @mode and @path for symlinks. Returns error or zero for success. */
errno_t obj40_create_stat(reiser4_object_t *obj, 
			  uint64_t size, uint64_t bytes, 
			  uint64_t rdev, uint32_t nlink, 
			  uint16_t mode, char *str)
{
	sdhint_unix_t unixh;
	sdhint_plug_t plugh;
	sdhint_plug_t heirh;
	sdhint_crypto_t crch;
	sdhint_lw_t lwh;
	stat_hint_t stat;
	trans_hint_t hint;
	lookup_t lookup;
	int64_t res;
	
	aal_assert("vpf-1592", obj != NULL);
	aal_assert("vpf-1593", reiser4_psstat(obj) != NULL);
	
	aal_memset(&hint, 0, sizeof(hint));
	
	/* Getting statdata plugin */
	hint.plug = reiser4_psstat(obj);

	hint.count = 1;
	hint.shift_flags = SF_DEFAULT;
	
	aal_memcpy(&hint.offset, &obj->info.object, sizeof(hint.offset));