/* ----------------
 *		heap_attisnull	- returns TRUE iff tuple attribute is not present
 * ----------------
 */
bool
heap_attisnull(HeapTuple tup, int attnum)
{
	if (attnum > (int) HeapTupleHeaderGetNatts(tup->t_data))
		return true;

	if (attnum > 0)
	{
		if (HeapTupleNoNulls(tup))
			return false;
		return att_isnull(attnum - 1, tup->t_data->t_bits);
	}

	switch (attnum)
	{
		case TableOidAttributeNumber:
		case SelfItemPointerAttributeNumber:
		case ObjectIdAttributeNumber:
		case MinTransactionIdAttributeNumber:
		case MinCommandIdAttributeNumber:
		case MaxTransactionIdAttributeNumber:
		case MaxCommandIdAttributeNumber:
			/* these are never null */
			break;

		default:
			elog(ERROR, "invalid attnum: %d", attnum);
	}

	return false;
}
Exemple #2
0
bool
heap_attisnull_normalattr(HeapTuple tup, int attnum)
{
	Assert(attnum > 0);
	if (HeapTupleNoNulls(tup))
		return false;
	return att_isnull(attnum - 1, tup->t_data->t_bits);
}
Exemple #3
0
/*
 * Try to decode a tuple using a types string provided previously.
 *
 * Arguments:
 *   tupleData   - pointer to the tuple data
 *   tupleSize   - tuple size in bytes
 */
void
FormatDecode(const char *tupleData, unsigned int tupleSize)
{
	HeapTupleHeader header = (HeapTupleHeader) tupleData;
	const char *data = tupleData + header->t_hoff;
	unsigned int size = tupleSize - header->t_hoff;
	int			curr_attr;

	CopyClear();

	for (curr_attr = 0; curr_attr < ncallbacks; curr_attr++)
	{
		int			ret;
		unsigned int processed_size = 0;

		if ((header->t_infomask & HEAP_HASNULL) && att_isnull(curr_attr, header->t_bits))
		{
			CopyAppend("\\N");
			continue;
		}

		if (size <= 0)
		{
			printf("Error: unable to decode a tuple, no more bytes left. Partial data: %s\n",
				   copyString.data);
			return;
		}

		ret = callbacks[curr_attr] (data, size, &processed_size);
		if (ret < 0)
		{
			printf("Error: unable to decode a tuple, callback #%d returned %d. Partial data: %s\n",
				   curr_attr + 1, ret, copyString.data);
			return;
		}

		size -= processed_size;
		data += processed_size;
	}

	if (size != 0)
	{
		printf("Error: unable to decode a tuple, %d bytes left, 0 expected. Partial data: %s\n",
			   size, copyString.data);
		return;
	}

	CopyFlush();
}
Exemple #4
0
/* ----------------
 *		heap_attisnull	- returns true iff tuple attribute is not present
 * ----------------
 */
bool
heap_attisnull(HeapTuple tup, int attnum, TupleDesc tupleDesc)
{
	/*
	 * We allow a NULL tupledesc for relations not expected to have missing
	 * values, such as catalog relations and indexes.
	 */
	Assert(!tupleDesc || attnum <= tupleDesc->natts);
	if (attnum > (int) HeapTupleHeaderGetNatts(tup->t_data))
	{
		if (tupleDesc && TupleDescAttr(tupleDesc, attnum - 1)->atthasmissing)
			return false;
		else
			return true;
	}

	if (attnum > 0)
	{
		if (HeapTupleNoNulls(tup))
			return false;
		return att_isnull(attnum - 1, tup->t_data->t_bits);
	}

	switch (attnum)
	{
		case TableOidAttributeNumber:
		case SelfItemPointerAttributeNumber:
		case MinTransactionIdAttributeNumber:
		case MinCommandIdAttributeNumber:
		case MaxTransactionIdAttributeNumber:
		case MaxCommandIdAttributeNumber:
			/* these are never null */
			break;

		default:
			elog(ERROR, "invalid attnum: %d", attnum);
	}

	return false;
}
Exemple #5
0
HeapTuple
CheckerConstraints(Checker *checker, HeapTuple tuple, int *parsing_field)
{
	if (checker->has_constraints)
	{
		*parsing_field = 0;

		/* Place tuple in tuple slot */
		ExecStoreTuple(tuple, checker->slot, InvalidBuffer, false);

		/* Check the constraints of the tuple */
		ExecConstraints(checker->resultRelInfo, checker->slot, checker->estate);
	}
	else if (checker->has_not_null && HeapTupleHasNulls(tuple))
	{
		/*
		 * Even if CHECK_CONSTRAINTS is not specified, check NOT NULL constraint
		 */
		TupleDesc	desc = checker->desc;
		int			i;

		for (i = 0; i < desc->natts; i++)
		{
			if (desc->attrs[i]->attnotnull &&
				att_isnull(i, tuple->t_data->t_bits))
			{
				*parsing_field = i + 1;	/* 1 origin */
				ereport(ERROR,
						(errcode(ERRCODE_NOT_NULL_VIOLATION),
						 errmsg("null value in column \"%s\" violates not-null constraint",
						NameStr(desc->attrs[i]->attname))));
			}
		}
	}

	return tuple;
}
Exemple #6
0
/*
 * slot_deform_tuple
 *		Given a TupleTableSlot, extract data from the slot's physical tuple
 *		into its Datum/isnull arrays.  Data is extracted up through the
 *		natts'th column (caller must ensure this is a legal column number).
 *
 *		This is essentially an incremental version of heap_deform_tuple:
 *		on each call we extract attributes up to the one needed, without
 *		re-computing information about previously extracted attributes.
 *		slot->tts_nvalid is the number of attributes already extracted.
 */
static void
slot_deform_tuple(TupleTableSlot *slot, int natts)
{
	HeapTuple	tuple = TupGetHeapTuple(slot); 
	TupleDesc	tupleDesc = slot->tts_tupleDescriptor;
	Datum	   *values = slot->PRIVATE_tts_values;
	bool	   *isnull = slot->PRIVATE_tts_isnull;
	HeapTupleHeader tup = tuple->t_data;
	bool		hasnulls = HeapTupleHasNulls(tuple);
	Form_pg_attribute *att = tupleDesc->attrs;
	int			attnum;
	char	   *tp;				/* ptr to tuple data */
	long		off;			/* offset in tuple data */
	bits8	   *bp = tup->t_bits;		/* ptr to null bitmap in tuple */
	bool		slow;			/* can we use/set attcacheoff? */

	/*
	 * Check whether the first call for this tuple, and initialize or restore
	 * loop state.
	 */
	attnum = slot->PRIVATE_tts_nvalid;
	if (attnum == 0)
	{
		/* Start from the first attribute */
		off = 0;
		slow = false;
	}
	else
	{
		/* Restore state from previous execution */
		off = slot->PRIVATE_tts_off;
		slow = slot->PRIVATE_tts_slow;
	}

	tp = (char *) tup + tup->t_hoff;

	for (; attnum < natts; attnum++)
	{
		Form_pg_attribute thisatt = att[attnum];

		if (hasnulls && att_isnull(attnum, bp))
		{
			values[attnum] = (Datum) 0;
			isnull[attnum] = true;
			slow = true;		/* can't use attcacheoff anymore */
			continue;
		}

		isnull[attnum] = false;

		if (!slow && thisatt->attcacheoff >= 0)
			off = thisatt->attcacheoff;
		else if (thisatt->attlen == -1)
		{
			/*
			 * We can only cache the offset for a varlena attribute if the
			 * offset is already suitably aligned, so that there would be no
			 * pad bytes in any case: then the offset will be valid for either
			 * an aligned or unaligned value.
			 */
			if (!slow &&
				off == att_align_nominal(off, thisatt->attalign))
				thisatt->attcacheoff = off;
			else
			{
				off = att_align_pointer(off, thisatt->attalign, -1,
										tp + off);
				slow = true;
			}
		}
		else
		{
			/* not varlena, so safe to use att_align_nominal */
			off = att_align_nominal(off, thisatt->attalign);

			if (!slow)
				thisatt->attcacheoff = off;
		}
		if (!slow && thisatt->attlen < 0)
			slow = true;

		values[attnum] = fetchatt(thisatt, tp + off);

		off = att_addlength_pointer(off, thisatt->attlen, tp + off);

		if (thisatt->attlen <= 0)
			slow = true;		/* can't use attcacheoff anymore */
	}

	/*
	 * Save state for next execution
	 */
	slot->PRIVATE_tts_nvalid = attnum;
	slot->PRIVATE_tts_off = off;
	slot->PRIVATE_tts_slow = slow;
}
Exemple #7
0
/*
 * tuple_data_split_internal
 *
 * Split raw tuple data taken directly from a page into an array of bytea
 * elements. This routine does a lookup on NULL values and creates array
 * elements accordingly. This is a reimplementation of nocachegetattr()
 * in heaptuple.c simplified for educational purposes.
 */
static Datum
tuple_data_split_internal(Oid relid, char *tupdata,
						  uint16 tupdata_len, uint16 t_infomask,
						  uint16 t_infomask2, bits8 *t_bits,
						  bool do_detoast)
{
	ArrayBuildState *raw_attrs;
	int			nattrs;
	int			i;
	int			off = 0;
	Relation	rel;
	TupleDesc	tupdesc;

	/* Get tuple descriptor from relation OID */
	rel = relation_open(relid, AccessShareLock);
	tupdesc = RelationGetDescr(rel);

	raw_attrs = initArrayResult(BYTEAOID, CurrentMemoryContext, false);
	nattrs = tupdesc->natts;

	if (nattrs < (t_infomask2 & HEAP_NATTS_MASK))
		ereport(ERROR,
				(errcode(ERRCODE_DATA_CORRUPTED),
				 errmsg("number of attributes in tuple header is greater than number of attributes in tuple descriptor")));

	for (i = 0; i < nattrs; i++)
	{
		Form_pg_attribute attr;
		bool		is_null;
		bytea	   *attr_data = NULL;

		attr = TupleDescAttr(tupdesc, i);

		/*
		 * Tuple header can specify less attributes than tuple descriptor as
		 * ALTER TABLE ADD COLUMN without DEFAULT keyword does not actually
		 * change tuples in pages, so attributes with numbers greater than
		 * (t_infomask2 & HEAP_NATTS_MASK) should be treated as NULL.
		 */
		if (i >= (t_infomask2 & HEAP_NATTS_MASK))
			is_null = true;
		else
			is_null = (t_infomask & HEAP_HASNULL) && att_isnull(i, t_bits);

		if (!is_null)
		{
			int			len;

			if (attr->attlen == -1)
			{
				off = att_align_pointer(off, attr->attalign, -1,
										tupdata + off);

				/*
				 * As VARSIZE_ANY throws an exception if it can't properly
				 * detect the type of external storage in macros VARTAG_SIZE,
				 * this check is repeated to have a nicer error handling.
				 */
				if (VARATT_IS_EXTERNAL(tupdata + off) &&
					!VARATT_IS_EXTERNAL_ONDISK(tupdata + off) &&
					!VARATT_IS_EXTERNAL_INDIRECT(tupdata + off))
					ereport(ERROR,
							(errcode(ERRCODE_DATA_CORRUPTED),
							 errmsg("first byte of varlena attribute is incorrect for attribute %d", i)));

				len = VARSIZE_ANY(tupdata + off);
			}
			else
			{
				off = att_align_nominal(off, attr->attalign);
				len = attr->attlen;
			}

			if (tupdata_len < off + len)
				ereport(ERROR,
						(errcode(ERRCODE_DATA_CORRUPTED),
						 errmsg("unexpected end of tuple data")));

			if (attr->attlen == -1 && do_detoast)
				attr_data = DatumGetByteaPCopy(tupdata + off);
			else
			{
				attr_data = (bytea *) palloc(len + VARHDRSZ);
				SET_VARSIZE(attr_data, len + VARHDRSZ);
				memcpy(VARDATA(attr_data), tupdata + off, len);
			}

			off = att_addlength_pointer(off, attr->attlen,
										tupdata + off);
		}

		raw_attrs = accumArrayResult(raw_attrs, PointerGetDatum(attr_data),
									 is_null, BYTEAOID, CurrentMemoryContext);
		if (attr_data)
			pfree(attr_data);
	}

	if (tupdata_len != off)
		ereport(ERROR,
				(errcode(ERRCODE_DATA_CORRUPTED),
				 errmsg("end of tuple reached without looking at all its data")));

	relation_close(rel, AccessShareLock);

	return makeArrayResult(raw_attrs, CurrentMemoryContext);
}
Exemple #8
0
/*
 * Convert an index tuple into Datum/isnull arrays.
 *
 * The caller must allocate sufficient storage for the output arrays.
 * (INDEX_MAX_KEYS entries should be enough.)
 *
 * This is nearly the same as heap_deform_tuple(), but for IndexTuples.
 * One difference is that the tuple should never have any missing columns.
 */
void
index_deform_tuple(IndexTuple tup, TupleDesc tupleDescriptor,
				   Datum *values, bool *isnull)
{
	int			hasnulls = IndexTupleHasNulls(tup);
	int			natts = tupleDescriptor->natts; /* number of atts to extract */
	int			attnum;
	char	   *tp;				/* ptr to tuple data */
	int			off;			/* offset in tuple data */
	bits8	   *bp;				/* ptr to null bitmap in tuple */
	bool		slow = false;	/* can we use/set attcacheoff? */

	/* Assert to protect callers who allocate fixed-size arrays */
	Assert(natts <= INDEX_MAX_KEYS);

	/* XXX "knows" t_bits are just after fixed tuple header! */
	bp = (bits8 *) ((char *) tup + sizeof(IndexTupleData));

	tp = (char *) tup + IndexInfoFindDataOffset(tup->t_info);
	off = 0;

	for (attnum = 0; attnum < natts; attnum++)
	{
		Form_pg_attribute thisatt = TupleDescAttr(tupleDescriptor, attnum);

		if (hasnulls && att_isnull(attnum, bp))
		{
			values[attnum] = (Datum) 0;
			isnull[attnum] = true;
			slow = true;		/* can't use attcacheoff anymore */
			continue;
		}

		isnull[attnum] = false;

		if (!slow && thisatt->attcacheoff >= 0)
			off = thisatt->attcacheoff;
		else if (thisatt->attlen == -1)
		{
			/*
			 * We can only cache the offset for a varlena attribute if the
			 * offset is already suitably aligned, so that there would be no
			 * pad bytes in any case: then the offset will be valid for either
			 * an aligned or unaligned value.
			 */
			if (!slow &&
				off == att_align_nominal(off, thisatt->attalign))
				thisatt->attcacheoff = off;
			else
			{
				off = att_align_pointer(off, thisatt->attalign, -1,
										tp + off);
				slow = true;
			}
		}
		else
		{
			/* not varlena, so safe to use att_align_nominal */
			off = att_align_nominal(off, thisatt->attalign);

			if (!slow)
				thisatt->attcacheoff = off;
		}

		values[attnum] = fetchatt(thisatt, tp + off);

		off = att_addlength_pointer(off, thisatt->attlen, tp + off);

		if (thisatt->attlen <= 0)
			slow = true;		/* can't use attcacheoff anymore */
	}
}
Exemple #9
0
static void
convert_heaptuple(HeapTupleHeader htup)
{
	/* HEAP_HASEXTENDED and HEAP_HASCOMPRESSED flags were removed. Clear them out */
	htup->t_infomask &= ~(VERSION4_HEAP_HASEXTENDED | VERSION4_HEAP_HASCOMPRESSED);

	/* HEAP_HASOID flag was moved */
	if (htup->t_infomask & VERSION4_HEAP_HASOID)
	{
		htup->t_infomask &= ~(VERSION4_HEAP_HASOID);
		htup->t_infomask |= HEAP_HASOID;
	}

	/* Any numeric columns? */
	if (curr_hasnumerics)
	{
		/* This is like heap_deform_tuple() */

		bool		hasnulls = (htup->t_infomask & HEAP_HASNULL) != 0;
		int			attnum;
		char	   *tp;
		long		off;
		bits8	   *bp = htup->t_bits;		/* ptr to null bitmap in tuple */

		tp = (char *) htup + htup->t_hoff;

		off = 0;

		for (attnum = 0; attnum < curr_natts; attnum++)
		{
			AttInfo	   *thisatt = &curr_atts[attnum];

			if (hasnulls && att_isnull(attnum, bp))
				continue;

			if (thisatt->attlen == -1)
			{
				off = att_align_pointer(off, thisatt->attalign, -1,
										tp + off);
			}
			else
			{
				/* not varlena, so safe to use att_align_nominal */
				off = att_align_nominal(off, thisatt->attalign);
			}

			if (thisatt->is_numeric)
			{
				/*
				 * Before PostgreSQL 8.3, the n_weight and n_sign_dscale fields
				 * were the other way 'round. Swap them.
				 *
				 * FIXME: need to handle toasted datums here.
				 */
				Datum		datum = PointerGetDatum(tp + off);

				if (VARATT_IS_COMPRESSED(datum))
					pg_log(PG_FATAL, "converting compressed numeric datums is not implemented\n");
				else if (VARATT_IS_EXTERNAL(datum))
					pg_log(PG_FATAL, "converting toasted numeric datums is not implemented\n");
				else
				{
					char	   *numericdata = VARDATA_ANY(DatumGetPointer(datum));
					int			sz = VARSIZE_ANY_EXHDR(DatumGetPointer(datum));
					uint16		tmp;

					if (sz < 4)
						pg_log(PG_FATAL, "unexpected size for numeric datum: %d\n", sz);

					memcpy(&tmp, &numericdata[0], 2);
					memcpy(&numericdata[0], &numericdata[2], 2);
					memcpy(&numericdata[2], &tmp, 2);
				}
			}

			off = att_addlength_pointer(off, thisatt->attlen, tp + off);
		}
	}
}
Exemple #10
0
/*
 * heap_deform_tuple
 *		Given a tuple, extract data into values/isnull arrays; this is
 *		the inverse of heap_form_tuple.
 *
 *		Storage for the values/isnull arrays is provided by the caller;
 *		it should be sized according to tupleDesc->natts not tuple->t_natts.
 *
 *		Note that for pass-by-reference datatypes, the pointer placed
 *		in the Datum will point into the given tuple.
 *
 *		When all or most of a tuple's fields need to be extracted,
 *		this routine will be significantly quicker than a loop around
 *		heap_getattr; the loop will become O(N^2) as soon as any
 *		noncacheable attribute offsets are involved.
 */
void
heap_deform_tuple(HeapTuple tuple, TupleDesc tupleDesc,
				  Datum *values, bool *isnull)
{
	HeapTupleHeader tup = tuple->t_data;
	bool		hasnulls = HeapTupleHasNulls(tuple);
	Form_pg_attribute *att = tupleDesc->attrs;
	int			tdesc_natts = tupleDesc->natts;
	int			natts;			/* number of atts to extract */
	int			attnum;
	char	   *tp;				/* ptr to tuple data */
	long		off;			/* offset in tuple data */
	bits8	   *bp = tup->t_bits;		/* ptr to null bitmap in tuple */
	bool		slow = false;	/* can we use/set attcacheoff? */

	Assert(!is_heaptuple_memtuple(tuple));
	natts = HeapTupleHeaderGetNatts(tup);

	/*
	 * In inheritance situations, it is possible that the given tuple actually
	 * has more fields than the caller is expecting.  Don't run off the end of
	 * the caller's arrays.
	 */
	natts = Min(natts, tdesc_natts);

	tp = (char *) tup + tup->t_hoff;

	off = 0;

	for (attnum = 0; attnum < natts; attnum++)
	{
		Form_pg_attribute thisatt = att[attnum];

		if (hasnulls && att_isnull(attnum, bp))
		{
			values[attnum] = (Datum) 0;
			isnull[attnum] = true;
			slow = true;		/* can't use attcacheoff anymore */
			continue;
		}

		isnull[attnum] = false;

		if (!slow && thisatt->attcacheoff >= 0)
			off = thisatt->attcacheoff;
		else
		{
			/* if it's a varlena it may or may not be aligned, so check for
			 * something that looks like a padding byte before aligning. If
			 * we're already aligned it may be the leading byte of a 4-byte
			 * header but then the att_align is harmless. Don't bother looking
			 * if it's not a varlena though.*/
			if (thisatt->attlen != -1 || !tp[off])
				off = att_align(off, thisatt->attalign);

			if (!slow && thisatt->attlen != -1)
				thisatt->attcacheoff = off;

		}
		if (!slow && thisatt->attlen < 0)
			slow = true;

		values[attnum] = fetchatt(thisatt, tp + off);

#ifdef USE_ASSERT_CHECKING
		/* Ignore attributes with dropped types */
		if (thisatt->attlen == -1 && !thisatt->attisdropped)
		{
			Assert(VARATT_IS_SHORT_D(values[attnum]) || 
				   !VARATT_COULD_SHORT_D(values[attnum]) ||
				   thisatt->atttypid == OIDVECTOROID ||
				   thisatt->atttypid == INT2VECTOROID ||
				   thisatt->atttypid >= FirstNormalObjectId);	
		}
#endif

		off = att_addlength(off, thisatt->attlen, PointerGetDatum(tp + off));
	}

	/*
	 * If tuple doesn't have all the atts indicated by tupleDesc, read the
	 * rest as null
	 */
	for (; attnum < tdesc_natts; attnum++)
	{
		values[attnum] = (Datum) 0;
		isnull[attnum] = true;
	}
}
Exemple #11
0
/* checks the individual attributes of the tuple */
uint32 check_index_tuple_attributes(Relation rel, PageHeader header, int block, int i, char *buffer) {
  
	IndexTuple tuple;
	uint32 nerrs = 0;
	int j, off;
	
	bits8 * bitmap;
	BTPageOpaque opaque;
	
	ereport(DEBUG2,(errmsg("[%d:%d] checking attributes for the tuple", block, i)));
	
	/* get the index tuple and info about the page */
	tuple = (IndexTuple)(buffer + header->pd_linp[i].lp_off);
	opaque = (BTPageOpaque)(buffer + header->pd_special);
	
	/* current attribute offset - always starts at (buffer + off) */
	off = header->pd_linp[i].lp_off + IndexInfoFindDataOffset(tuple->t_info);
	
	ereport(DEBUG3,(errmsg("[%d:%d] tuple has %d attributes", block, (i+1),
						   RelationGetNumberOfAttributes(rel))));
	
	bitmap = (bits8*)(buffer + header->pd_linp[i].lp_off + sizeof(IndexTupleData));
	
	/* TODO This is mostly copy'n'paste from check_heap_tuple_attributes,
	   so maybe it could be refactored to share the code. */

	/* For left-most tuples on non-leaf pages, there are no data actually
	   (see src/backend/access/nbtree/README, last paragraph in section "Notes
	   About Data Representation")
   
	   Use P_LEFTMOST/P_ISLEAF to identify such cases (for the leftmost item only)
	   and set len = 0.
	*/
	
	if (P_LEFTMOST(opaque) && (! P_ISLEAF(opaque)) && (i == 0)) {
		ereport(DEBUG3, (errmsg("[%d:%d] leftmost tuple on non-leaf block => no data, skipping", block, i)));
		return nerrs;
	}
	  
	/* check all the index attributes */
	for (j = 0; j < rel->rd_att->natts; j++) {
		
		/* default length of the attribute */
		int len = rel->rd_att->attrs[j]->attlen;
		
		/* copy from src/backend/commands/analyze.c */
		bool is_varlena  = (!rel->rd_att->attrs[j]->attbyval && len == -1);
		bool is_varwidth = (!rel->rd_att->attrs[j]->attbyval && len < 0); /* thus it's "len = -2" */
		
		/* if the attribute is marked as NULL (in the tuple header), skip to the next attribute */
		if (IndexTupleHasNulls(tuple) && att_isnull(j, bitmap)) {
			ereport(DEBUG3, (errmsg("[%d:%d] attribute '%s' is NULL (skipping)", block, (i+1), rel->rd_att->attrs[j]->attname.data)));
			continue;
		}

		/* fix the alignment (see src/include/access/tupmacs.h) */
		off = att_align_pointer(off, rel->rd_att->attrs[j]->attalign, rel->rd_att->attrs[j]->attlen, buffer+off);
		
		if (is_varlena) { 
		
			/*
			  other interesting macros (see postgres.h) - should do something about those ...
			  
			  VARATT_IS_COMPRESSED(PTR)			VARATT_IS_4B_C(PTR)
			  VARATT_IS_EXTERNAL(PTR)				VARATT_IS_1B_E(PTR)
			  VARATT_IS_SHORT(PTR)				VARATT_IS_1B(PTR)
			  VARATT_IS_EXTENDED(PTR)				(!VARATT_IS_4B_U(PTR))
			*/
			
			len = VARSIZE_ANY(buffer + off);
			
			if (len < 0) {
				ereport(WARNING, (errmsg("[%d:%d] attribute '%s' has negative length < 0 (%d)", block, (i+1), rel->rd_att->attrs[j]->attname.data, len)));
				++nerrs;
				break;
			}
			
			if (VARATT_IS_COMPRESSED(buffer + off)) {
				/* the raw length should be less than 1G (and positive) */
				if ((VARRAWSIZE_4B_C(buffer + off) < 0) || (VARRAWSIZE_4B_C(buffer + off) > 1024*1024)) {
					ereport(WARNING, (errmsg("[%d:%d]  attribute '%s' has invalid length %d (should be between 0 and 1G)", block, (i+1), rel->rd_att->attrs[j]->attname.data, VARRAWSIZE_4B_C(buffer + off))));
					++nerrs;
					/* no break here, this does not break the page structure - we may check the other attributes */
				}
			}
				
			/* FIXME Check if the varlena value may be detoasted. */
			
		} else if (is_varwidth) {
		
			/* get the C-string length (at most to the end of tuple), +1 as it does not include '\0' at the end */
			/* if the string is not properly terminated, then this returns 'remaining space + 1' so it's detected */
			len = strnlen(buffer + off, header->pd_linp[i].lp_off + len + header->pd_linp[i].lp_len - off) + 1;
			
		}
			
		/* Check if the length makes sense (is not negative and does not overflow
		 * the tuple end, stop validating the other rows (we don't know where to
		 * continue anyway). */
		
		if (off + len > (header->pd_linp[i].lp_off + header->pd_linp[i].lp_len)) {
			ereport(WARNING, (errmsg("[%d:%d] attribute '%s' (off=%d len=%d) overflows tuple end (off=%d, len=%d)", block, (i+1), rel->rd_att->attrs[j]->attname.data, off, len, header->pd_linp[i].lp_off, header->pd_linp[i].lp_len)));
			++nerrs;
			break;
		}
		
		/* skip to the next attribute */
		off += len;
		
		ereport(DEBUG3,(errmsg("[%d:%d] attribute '%s' len=%d", block, (i+1), rel->rd_att->attrs[j]->attname.data, len)));
		
	}
	
	ereport(DEBUG3,(errmsg("[%d:%d] last attribute ends at %d, tuple ends at %d", block, (i+1), off, header->pd_linp[i].lp_off + header->pd_linp[i].lp_len)));
	
	/* after the last attribute, the offset should be exactly the same as the end of the tuple */
	if (MAXALIGN(off) != header->pd_linp[i].lp_off + header->pd_linp[i].lp_len) {
		ereport(WARNING, (errmsg("[%d:%d] the last attribute ends at %d but the tuple ends at %d", block, (i+1), off, header->pd_linp[i].lp_off + header->pd_linp[i].lp_len)));
		++nerrs;
	}
	
	return nerrs;

}
Exemple #12
0
/* ----------------
 *		nocache_index_getattr
 *
 *		This gets called from index_getattr() macro, and only in cases
 *		where we can't use cacheoffset and the value is not null.
 *
 *		This caches attribute offsets in the attribute descriptor.
 *
 *		An alternate way to speed things up would be to cache offsets
 *		with the tuple, but that seems more difficult unless you take
 *		the storage hit of actually putting those offsets into the
 *		tuple you send to disk.  Yuck.
 *
 *		This scheme will be slightly slower than that, but should
 *		perform well for queries which hit large #'s of tuples.  After
 *		you cache the offsets once, examining all the other tuples using
 *		the same attribute descriptor will go much quicker. -cim 5/4/91
 * ----------------
 */
Datum
nocache_index_getattr(IndexTuple tup,
					  int attnum,
					  TupleDesc tupleDesc,
					  bool *isnull)
{
	Form_pg_attribute *att = tupleDesc->attrs;
	char	   *tp;				/* ptr to att in tuple */
	bits8	   *bp = NULL;		/* ptr to null bitmask in tuple */
	bool		slow = false;	/* do we have to walk nulls? */
	int			data_off;		/* tuple data offset */

	(void) isnull;				/* not used */

	/*
	 * sanity checks
	 */

	/* ----------------
	 *	 Three cases:
	 *
	 *	 1: No nulls and no variable-width attributes.
	 *	 2: Has a null or a var-width AFTER att.
	 *	 3: Has nulls or var-widths BEFORE att.
	 * ----------------
	 */

#ifdef IN_MACRO
/* This is handled in the macro */
	Assert(PointerIsValid(isnull));
	Assert(attnum > 0);

	*isnull = false;
#endif

	data_off = IndexInfoFindDataOffset(tup->t_info);

	attnum--;

	if (!IndexTupleHasNulls(tup))
	{
#ifdef IN_MACRO
/* This is handled in the macro */
		if (att[attnum]->attcacheoff != -1)
		{
			return fetchatt(att[attnum],
							(char *) tup + data_off +
							att[attnum]->attcacheoff);
		}
#endif
	}
	else
	{
		/*
		 * there's a null somewhere in the tuple
		 *
		 * check to see if desired att is null
		 */

		/* XXX "knows" t_bits are just after fixed tuple header! */
		bp = (bits8 *) ((char *) tup + sizeof(IndexTupleData));

#ifdef IN_MACRO
/* This is handled in the macro */

		if (att_isnull(attnum, bp))
		{
			*isnull = true;
			return (Datum) NULL;
		}
#endif

		/*
		 * Now check to see if any preceding bits are null...
		 */
		{
			int			byte = attnum >> 3;
			int			finalbit = attnum & 0x07;

			/* check for nulls "before" final bit of last byte */
			if ((~bp[byte]) & ((1 << finalbit) - 1))
				slow = true;
			else
			{
				/* check for nulls in any "earlier" bytes */
				int			i;

				for (i = 0; i < byte; i++)
				{
					if (bp[i] != 0xFF)
					{
						slow = true;
						break;
					}
				}
			}
		}
	}

	tp = (char *) tup + data_off;

	/*
	 * now check for any non-fixed length attrs before our attribute
	 */
	if (!slow)
	{
		if (att[attnum]->attcacheoff != -1)
		{
			return fetchatt(att[attnum],
							tp + att[attnum]->attcacheoff);
		}
		else if (IndexTupleHasVarwidths(tup))
		{
			int			j;

			for (j = 0; j < attnum; j++)
			{
				if (att[j]->attlen <= 0)
				{
					slow = true;
					break;
				}
			}
		}
	}

	/*
	 * If slow is false, and we got here, we know that we have a tuple with no
	 * nulls or var-widths before the target attribute. If possible, we also
	 * want to initialize the remainder of the attribute cached offset values.
	 */
	if (!slow)
	{
		int			j = 1;
		long		off;

		/*
		 * need to set cache for some atts
		 */

		att[0]->attcacheoff = 0;

		while (j < attnum && att[j]->attcacheoff > 0)
			j++;

		off = att[j - 1]->attcacheoff + att[j - 1]->attlen;

		for (; j <= attnum; j++)
		{
			off = att_align(off, att[j]->attalign);

			att[j]->attcacheoff = off;

			off += att[j]->attlen;
		}

		return fetchatt(att[attnum], tp + att[attnum]->attcacheoff);
	}
	else
	{
		bool		usecache = true;
		int			off = 0;
		int			i;

		/*
		 * Now we know that we have to walk the tuple CAREFULLY.
		 */

		for (i = 0; i < attnum; i++)
		{
			if (IndexTupleHasNulls(tup))
			{
				if (att_isnull(i, bp))
				{
					usecache = false;
					continue;
				}
			}

			/* If we know the next offset, we can skip the rest */
			if (usecache && att[i]->attcacheoff != -1)
				off = att[i]->attcacheoff;
			else
			{
				off = att_align(off, att[i]->attalign);

				if (usecache)
					att[i]->attcacheoff = off;
			}

			off = att_addlength(off, att[i]->attlen, tp + off);

			if (usecache && att[i]->attlen <= 0)
				usecache = false;
		}

		off = att_align(off, att[attnum]->attalign);

		return fetchatt(att[attnum], tp + off);
	}
}
Exemple #13
0
/* ----------------
 *		nocachegetattr
 *
 *		This only gets called from fastgetattr() macro, in cases where
 *		we can't use a cacheoffset and the value is not null.
 *
 *		This caches attribute offsets in the attribute descriptor.
 *
 *		An alternative way to speed things up would be to cache offsets
 *		with the tuple, but that seems more difficult unless you take
 *		the storage hit of actually putting those offsets into the
 *		tuple you send to disk.  Yuck.
 *
 *		This scheme will be slightly slower than that, but should
 *		perform well for queries which hit large #'s of tuples.  After
 *		you cache the offsets once, examining all the other tuples using
 *		the same attribute descriptor will go much quicker. -cim 5/4/91
 *
 *		NOTE: if you need to change this code, see also heap_deform_tuple.
 *		Also see nocache_index_getattr, which is the same code for index
 *		tuples.
 * ----------------
 */
Datum
nocachegetattr(HeapTuple tuple,
			   int attnum,
			   TupleDesc tupleDesc)
{
	HeapTupleHeader tup = tuple->t_data;
	Form_pg_attribute *att = tupleDesc->attrs;
	char	   *tp;				/* ptr to att in tuple */
	bits8	   *bp = tup->t_bits;		/* ptr to null bitmap in tuple */
	bool		slow = false;	/* do we have to walk nulls? */

	Assert(!is_heaptuple_memtuple(tuple));
	/* If any cached offsets are there we can check that they make sense, but
	 * there may not be any at all, so pass -1 for the attnum we know is valid */

#ifdef IN_MACRO
/* This is handled in the macro */
	Assert(attnum > 0);

	if (isnull)
		*isnull = false;
#endif

	attnum--;

	/* ----------------
	 *	 Three cases:
	 *
	 *	 1: No nulls and no variable-width attributes.
	 *	 2: Has a null or a var-width AFTER att.
	 *	 3: Has nulls or var-widths BEFORE att.
	 * ----------------
	 */

	if (HeapTupleNoNulls(tuple))
	{
#ifdef IN_MACRO
/* This is handled in the macro */
		if (att[attnum]->attcacheoff != -1)
		{
			return fetchatt(att[attnum],
							(char *) tup + tup->t_hoff +
							att[attnum]->attcacheoff);
		}
#endif
	}
	else
	{
		/*
		 * there's a null somewhere in the tuple
		 *
		 * check to see if desired att is null
		 */

#ifdef IN_MACRO
/* This is handled in the macro */
		if (att_isnull(attnum, bp))
		{
			if (isnull)
				*isnull = true;
			return (Datum) NULL;
		}
#endif

		/*
		 * Now check to see if any preceding bits are null...
		 */
		{
			int			byte = attnum >> 3;
			int			finalbit = attnum & 0x07;

			/* check for nulls "before" final bit of last byte */
			if ((~bp[byte]) & ((1 << finalbit) - 1))
				slow = true;
			else
			{
				/* check for nulls in any "earlier" bytes */
				int			i;

				for (i = 0; i < byte; i++)
				{
					if (bp[i] != 0xFF)
					{
						slow = true;
						break;
					}
				}
			}
		}
	}

	tp = (char *) tup + tup->t_hoff;

	/*
	 * now check for any non-fixed length attrs before our attribute
	 */
	if (!slow)
	{
		/*
		 * If we get here, there are no nulls up to and including the target
		 * attribute.  If we have a cached offset, we can use it.
		 */
		if (att[attnum]->attcacheoff >= 0)
		{
			return fetchatt(att[attnum],
							tp + att[attnum]->attcacheoff);
		}

		/*
		 * Otherwise, check for non-fixed-length attrs up to and including
		 * target.	If there aren't any, it's safe to cheaply initialize the
		 * cached offsets for these attrs.
		 */
		if (HeapTupleHasVarWidth(tuple))
		{
			int			j;

			/*
			 * In for(), we test <= and not < because we want to see if we can
			 * go past it in initializing offsets.
			 */
			for (j = 0; j <= attnum; j++)
			{
				if (att[j]->attlen <= 0)
				{
					slow = true;
					break;
				}
			}
		}
	}

	/*
	 * If slow is false, and we got here, we know that we have a tuple with no
	 * nulls or var-widths before the target attribute. If possible, we also
	 * want to initialize the remainder of the attribute cached offset values.
	 */
	if (!slow)
	{
		int			j = 1;
		long		off;
		int			natts = HeapTupleHeaderGetNatts(tup);

		/*
		 * If we get here, we have a tuple with no nulls or var-widths up to
		 * and including the target attribute, so we can use the cached offset
		 * ... only we don't have it yet, or we'd not have got here.  Since
		 * it's cheap to compute offsets for fixed-width columns, we take the
		 * opportunity to initialize the cached offsets for *all* the leading
		 * fixed-width columns, in hope of avoiding future visits to this
		 * routine.
		 */

		/* this is always true */
		att[0]->attcacheoff = 0;

		while (j < attnum && att[j]->attcacheoff > 0)
			j++;

		off = att[j - 1]->attcacheoff + att[j - 1]->attlen;

		for (; j <= attnum ||
		/* Can we compute more?  We will probably need them */
			 (j < natts &&
			  att[j]->attcacheoff == -1 &&
			  (HeapTupleNoNulls(tuple) || !att_isnull(j, bp)) &&
			  (HeapTupleAllFixed(tuple) || att[j]->attlen > 0)); j++)
		{
			/* don't need to worry about shortvarlenas here since we're only
			 * looking at non-varlenas. Note that it's important that we check
			 * that the target attribute itself is a nonvarlena too since we
			 * can't use cached offsets for even the first varlena any more. */
			off = att_align(off, att[j]->attalign);

			att[j]->attcacheoff = off;

			off = att_addlength(off, att[j]->attlen, PointerGetDatum(tp + off));
		}

		return fetchatt(att[attnum], tp + att[attnum]->attcacheoff);
	}
	else
	{
		bool		usecache = true;
		int			off = 0;
		int			i;

		/* this is always true */
		att[0]->attcacheoff = 0;

		/*
		 * Now we know that we have to walk the tuple CAREFULLY.
		 *
		 * Note - This loop is a little tricky.  For each non-null attribute,
		 * we have to first account for alignment padding before the attr,
		 * then advance over the attr based on its length.	Nulls have no
		 * storage and no alignment padding either.  We can use/set
		 * attcacheoff until we reach either a null or a var-width attribute.
		 */

		for (i = 0; i < attnum; i++)
		{
			if (HeapTupleHasNulls(tuple) && att_isnull(i, bp))
			{
				usecache = false;
				continue;
			}

			/* If we know the next offset, we can skip the alignment calc */
			if (usecache && att[i]->attcacheoff != -1)
				off = att[i]->attcacheoff;
			else
			{
				/* if it's a varlena it may or may not be aligned, so check for
				 * something that looks like a padding byte before aligning. If
				 * we're already aligned it may be the leading byte of a 4-byte
				 * header but then the att_align is harmless. Don't bother
				 * looking if it's not a varlena though.*/
				if (att[i]->attlen != -1 || !tp[off])
					off = att_align(off, att[i]->attalign);
				if (usecache && att[i]->attlen != -1)
					att[i]->attcacheoff = off;
			}

			if (att[i]->attlen < 0)
				usecache = false;

			off = att_addlength(off, att[i]->attlen, PointerGetDatum(tp + off));
		}

		if (att[attnum]->attlen != -1 || !tp[off])
			off = att_align(off, att[attnum]->attalign);

		return fetchatt(att[attnum], tp + off);
	}
}
/* ----------------
 *		nocache_index_getattr
 *
 *		This gets called from index_getattr() macro, and only in cases
 *		where we can't use cacheoffset and the value is not null.
 *
 *		This caches attribute offsets in the attribute descriptor.
 *
 *		An alternative way to speed things up would be to cache offsets
 *		with the tuple, but that seems more difficult unless you take
 *		the storage hit of actually putting those offsets into the
 *		tuple you send to disk.  Yuck.
 *
 *		This scheme will be slightly slower than that, but should
 *		perform well for queries which hit large #'s of tuples.  After
 *		you cache the offsets once, examining all the other tuples using
 *		the same attribute descriptor will go much quicker. -cim 5/4/91
 * ----------------
 */
Datum
nocache_index_getattr(IndexTuple tup,
					  int attnum,
					  TupleDesc tupleDesc)
{
	Form_pg_attribute *att = tupleDesc->attrs;
	char	   *tp;				/* ptr to data part of tuple */
	bits8	   *bp = NULL;		/* ptr to null bitmap in tuple */
	bool		slow = false;	/* do we have to walk attrs? */
	int			data_off;		/* tuple data offset */
	int			off;			/* current offset within data */

	/* ----------------
	 *	 Three cases:
	 *
	 *	 1: No nulls and no variable-width attributes.
	 *	 2: Has a null or a var-width AFTER att.
	 *	 3: Has nulls or var-widths BEFORE att.
	 * ----------------
	 */

	data_off = IndexInfoFindDataOffset(tup->t_info);

	attnum--;

	if (IndexTupleHasNulls(tup))
	{
		/*
		 * there's a null somewhere in the tuple
		 *
		 * check to see if desired att is null
		 */

		/* XXX "knows" t_bits are just after fixed tuple header! */
		bp = (bits8 *) ((char *) tup + sizeof(IndexTupleData));

		/*
		 * Now check to see if any preceding bits are null...
		 */
		{
			int			byte = attnum >> 3;
			int			finalbit = attnum & 0x07;

			/* check for nulls "before" final bit of last byte */
			if ((~bp[byte]) & ((1 << finalbit) - 1))
				slow = true;
			else
			{
				/* check for nulls in any "earlier" bytes */
				int			i;

				for (i = 0; i < byte; i++)
				{
					if (bp[i] != 0xFF)
					{
						slow = true;
						break;
					}
				}
			}
		}
	}

	tp = (char *) tup + data_off;

	if (!slow)
	{
		/*
		 * If we get here, there are no nulls up to and including the target
		 * attribute.  If we have a cached offset, we can use it.
		 */
		if (att[attnum]->attcacheoff >= 0)
		{
			return fetchatt(att[attnum],
							tp + att[attnum]->attcacheoff);
		}

		/*
		 * Otherwise, check for non-fixed-length attrs up to and including
		 * target.  If there aren't any, it's safe to cheaply initialize the
		 * cached offsets for these attrs.
		 */
		if (IndexTupleHasVarwidths(tup))
		{
			int			j;

			for (j = 0; j <= attnum; j++)
			{
				if (att[j]->attlen <= 0)
				{
					slow = true;
					break;
				}
			}
		}
	}

	if (!slow)
	{
		int			natts = tupleDesc->natts;
		int			j = 1;

		/*
		 * If we get here, we have a tuple with no nulls or var-widths up to
		 * and including the target attribute, so we can use the cached offset
		 * ... only we don't have it yet, or we'd not have got here.  Since
		 * it's cheap to compute offsets for fixed-width columns, we take the
		 * opportunity to initialize the cached offsets for *all* the leading
		 * fixed-width columns, in hope of avoiding future visits to this
		 * routine.
		 */
		att[0]->attcacheoff = 0;

		/* we might have set some offsets in the slow path previously */
		while (j < natts && att[j]->attcacheoff > 0)
			j++;

		off = att[j - 1]->attcacheoff + att[j - 1]->attlen;

		for (; j < natts; j++)
		{
			if (att[j]->attlen <= 0)
				break;

			off = att_align_nominal(off, att[j]->attalign);

			att[j]->attcacheoff = off;

			off += att[j]->attlen;
		}

		Assert(j > attnum);

		off = att[attnum]->attcacheoff;
	}
	else
	{
		bool		usecache = true;
		int			i;

		/*
		 * Now we know that we have to walk the tuple CAREFULLY.  But we still
		 * might be able to cache some offsets for next time.
		 *
		 * Note - This loop is a little tricky.  For each non-null attribute,
		 * we have to first account for alignment padding before the attr,
		 * then advance over the attr based on its length.  Nulls have no
		 * storage and no alignment padding either.  We can use/set
		 * attcacheoff until we reach either a null or a var-width attribute.
		 */
		off = 0;
		for (i = 0;; i++)		/* loop exit is at "break" */
		{
			if (IndexTupleHasNulls(tup) && att_isnull(i, bp))
			{
				usecache = false;
				continue;		/* this cannot be the target att */
			}

			/* If we know the next offset, we can skip the rest */
			if (usecache && att[i]->attcacheoff >= 0)
				off = att[i]->attcacheoff;
			else if (att[i]->attlen == -1)
			{
				/*
				 * We can only cache the offset for a varlena attribute if the
				 * offset is already suitably aligned, so that there would be
				 * no pad bytes in any case: then the offset will be valid for
				 * either an aligned or unaligned value.
				 */
				if (usecache &&
					off == att_align_nominal(off, att[i]->attalign))
					att[i]->attcacheoff = off;
				else
				{
					off = att_align_pointer(off, att[i]->attalign, -1,
											tp + off);
					usecache = false;
				}
			}
			else
			{
				/* not varlena, so safe to use att_align_nominal */
				off = att_align_nominal(off, att[i]->attalign);

				if (usecache)
					att[i]->attcacheoff = off;
			}

			if (i == attnum)
				break;

			off = att_addlength_pointer(off, att[i]->attlen, tp + off);

			if (usecache && att[i]->attlen <= 0)
				usecache = false;
		}
	}

	return fetchatt(att[attnum], tp + off);
}
Exemple #15
0
/*
 *		heap_deformtuple
 *
 *		Given a tuple, extract data into values/nulls arrays; this is
 *		the inverse of heap_formtuple.
 *
 *		Storage for the values/nulls arrays is provided by the caller;
 *		it should be sized according to tupleDesc->natts not tuple->t_natts.
 *
 *		Note that for pass-by-reference datatypes, the pointer placed
 *		in the Datum will point into the given tuple.
 *
 *		When all or most of a tuple's fields need to be extracted,
 *		this routine will be significantly quicker than a loop around
 *		heap_getattr; the loop will become O(N^2) as soon as any
 *		noncacheable attribute offsets are involved.
 *
 * OLD API with char 'n'/' ' convention for indicating nulls.
 * This is deprecated and should not be used in new code, but we keep it
 * around for use by old add-on modules.
 */
void
heap_deformtuple(HeapTuple tuple,
				 TupleDesc tupleDesc,
				 Datum *values,
				 char *nulls)
{
	HeapTupleHeader tup = tuple->t_data;
	bool		hasnulls = HeapTupleHasNulls(tuple);
	Form_pg_attribute *att = tupleDesc->attrs;
	int			tdesc_natts = tupleDesc->natts;
	int			natts;			/* number of atts to extract */
	int			attnum;
	char	   *tp;				/* ptr to tuple data */
	long		off;			/* offset in tuple data */
	bits8	   *bp = tup->t_bits;		/* ptr to null bitmap in tuple */
	bool		slow = false;	/* can we use/set attcacheoff? */

	natts = HeapTupleHeaderGetNatts(tup);

	/*
	 * In inheritance situations, it is possible that the given tuple actually
	 * has more fields than the caller is expecting.  Don't run off the end of
	 * the caller's arrays.
	 */
	natts = Min(natts, tdesc_natts);

	tp = (char *) tup + tup->t_hoff;

	off = 0;

	for (attnum = 0; attnum < natts; attnum++)
	{
		Form_pg_attribute thisatt = att[attnum];

		if (hasnulls && att_isnull(attnum, bp))
		{
			values[attnum] = (Datum) 0;
			nulls[attnum] = 'n';
			slow = true;		/* can't use attcacheoff anymore */
			continue;
		}

		nulls[attnum] = ' ';

		if (!slow && thisatt->attcacheoff >= 0)
			off = thisatt->attcacheoff;
		else if (thisatt->attlen == -1)
		{
			/*
			 * We can only cache the offset for a varlena attribute if the
			 * offset is already suitably aligned, so that there would be no
			 * pad bytes in any case: then the offset will be valid for either
			 * an aligned or unaligned value.
			 */
			if (!slow &&
				off == att_align_nominal(off, thisatt->attalign))
				thisatt->attcacheoff = off;
			else
			{
				off = att_align_pointer(off, thisatt->attalign, -1,
										tp + off);
				slow = true;
			}
		}
		else
		{
			/* not varlena, so safe to use att_align_nominal */
			off = att_align_nominal(off, thisatt->attalign);

			if (!slow)
				thisatt->attcacheoff = off;
		}

		values[attnum] = fetchatt(thisatt, tp + off);

		off = att_addlength_pointer(off, thisatt->attlen, tp + off);

		if (thisatt->attlen <= 0)
			slow = true;		/* can't use attcacheoff anymore */
	}

	/*
	 * If tuple doesn't have all the atts indicated by tupleDesc, read the
	 * rest as null
	 */
	for (; attnum < tdesc_natts; attnum++)
	{
		values[attnum] = (Datum) 0;
		nulls[attnum] = 'n';
	}
}
Exemple #16
0
/*
 * heap_deform_tuple
 *		Given a tuple, extract data into values/isnull arrays; this is
 *		the inverse of heap_form_tuple.
 *
 *		Storage for the values/isnull arrays is provided by the caller;
 *		it should be sized according to tupleDesc->natts not tuple->t_natts.
 *
 *		Note that for pass-by-reference datatypes, the pointer placed
 *		in the Datum will point into the given tuple.
 *
 *		When all or most of a tuple's fields need to be extracted,
 *		this routine will be significantly quicker than a loop around
 *		heap_getattr; the loop will become O(N^2) as soon as any
 *		noncacheable attribute offsets are involved.
 */
void
heap_deform_tuple(HeapTuple tuple, TupleDesc tupleDesc,
				  Datum *values, bool *isnull)
{
	HeapTupleHeader tup = tuple->t_data;
	bool		hasnulls = HeapTupleHasNulls(tuple);
	Form_pg_attribute *att = tupleDesc->attrs;
	int			tdesc_natts = tupleDesc->natts;
	int			natts;			/* number of atts to extract */
	int			attnum;
	char	   *tp;				/* ptr to tuple data */
	long		off;			/* offset in tuple data */
	bits8	   *bp = tup->t_bits;		/* ptr to null bitmap in tuple */
	bool		slow = false;	/* can we use/set attcacheoff? */

	Assert(!is_heaptuple_memtuple(tuple));
	natts = HeapTupleHeaderGetNatts(tup);

	/*
	 * In inheritance situations, it is possible that the given tuple actually
	 * has more fields than the caller is expecting.  Don't run off the end of
	 * the caller's arrays.
	 */
	natts = Min(natts, tdesc_natts);

	tp = (char *) tup + tup->t_hoff;

	off = 0;

	for (attnum = 0; attnum < natts; attnum++)
	{
		Form_pg_attribute thisatt = att[attnum];

		if (hasnulls && att_isnull(attnum, bp))
		{
			values[attnum] = (Datum) 0;
			isnull[attnum] = true;
			slow = true;		/* can't use attcacheoff anymore */
			continue;
		}

		isnull[attnum] = false;

		if (!slow && thisatt->attcacheoff >= 0)
			off = thisatt->attcacheoff;
		else if (thisatt->attlen == -1)
		{
			/*
			 * We can only cache the offset for a varlena attribute if the
			 * offset is already suitably aligned, so that there would be no
			 * pad bytes in any case: then the offset will be valid for either
			 * an aligned or unaligned value.
			 */
			if (!slow &&
				off == att_align_nominal(off, thisatt->attalign))
				thisatt->attcacheoff = off;
			else
			{
				off = att_align_pointer(off, thisatt->attalign, -1,
										tp + off);
				slow = true;
			}
		}
		else
		{
			/* not varlena, so safe to use att_align_nominal */
			off = att_align_nominal(off, thisatt->attalign);

			if (!slow)
				thisatt->attcacheoff = off;

		}
		if (!slow && thisatt->attlen < 0)
			slow = true;

		values[attnum] = fetchatt(thisatt, tp + off);

#ifdef USE_ASSERT_CHECKING
		/* Ignore attributes with dropped types */
		if (thisatt->attlen == -1 && !thisatt->attisdropped)
		{
			Assert(VARATT_IS_SHORT(DatumGetPointer(values[attnum])) ||
				   !VARATT_CAN_MAKE_SHORT(DatumGetPointer(values[attnum])) ||
				   thisatt->atttypid == OIDVECTOROID ||
				   thisatt->atttypid == INT2VECTOROID ||
				   thisatt->atttypid >= FirstNormalObjectId);	
		}
#endif

		off = att_addlength_pointer(off, thisatt->attlen, tp + off);
	}

	/*
	 * If tuple doesn't have all the atts indicated by tupleDesc, read the
	 * rest as null
	 */
	for (; attnum < tdesc_natts; attnum++)
	{
		values[attnum] = (Datum) 0;
		isnull[attnum] = true;
	}
}
Exemple #17
0
/*
 * load_auth_entries: read pg_authid into auth_entry[]
 *
 * auth_info_out: pointer to auth_entry * where address to auth_entry[] should be stored
 * total_roles_out: pointer to int where num of total roles should be stored
 */
static void
load_auth_entries(Relation rel_authid, auth_entry **auth_info_out, int *total_roles_out)
{
	BlockNumber totalblocks;
	HeapScanDesc scan;
	HeapTuple   tuple;
	int         curr_role = 0;
	int         total_roles = 0;
	int         est_rows;
	auth_entry *auth_info;

	/*
	 * Read pg_authid and fill temporary data structures.  Note we must read
	 * all roles, even those without rolcanlogin.
	 */
	totalblocks = RelationGetNumberOfBlocks(rel_authid);
	totalblocks = totalblocks ? totalblocks : 1;
	est_rows = totalblocks * (BLCKSZ / (sizeof(HeapTupleHeaderData) + sizeof(FormData_pg_authid)));
	auth_info = (auth_entry *) palloc(est_rows * sizeof(auth_entry));

	scan = heap_beginscan(rel_authid, SnapshotNow, 0, NULL);
	while ((tuple = heap_getnext(scan, ForwardScanDirection)) != NULL)
	{
		Form_pg_authid aform = (Form_pg_authid) GETSTRUCT(tuple);
		HeapTupleHeader tup = tuple->t_data;
		char	   *tp;			/* ptr to tuple data */
		long		off;		/* offset in tuple data */
		bits8	   *bp = tup->t_bits;	/* ptr to null bitmask in tuple */
		Datum		datum;

		if (curr_role >= est_rows)
		{
			est_rows *= 2;
			auth_info = (auth_entry *)
				repalloc(auth_info, est_rows * sizeof(auth_entry));
		}

		auth_info[curr_role].roleid = HeapTupleGetOid(tuple);
		auth_info[curr_role].rolsuper = aform->rolsuper;
		auth_info[curr_role].rolcanlogin = aform->rolcanlogin;
		auth_info[curr_role].rolname = pstrdup(NameStr(aform->rolname));
		auth_info[curr_role].member_of = NIL;

		/*
		 * We can't use heap_getattr() here because during startup we will not
		 * have any tupdesc for pg_authid.  Fortunately it's not too hard to
		 * work around this.  rolpassword is the first possibly-null field so
		 * we can compute its offset directly.
		 */
		tp = (char *) tup + tup->t_hoff;
		off = offsetof(FormData_pg_authid, rolpassword);

		if (HeapTupleHasNulls(tuple) &&
			att_isnull(Anum_pg_authid_rolpassword - 1, bp))
		{
			/* passwd is null, emit as an empty string */
			auth_info[curr_role].rolpassword = pstrdup("");
		}
		else
		{
			/* assume passwd is pass-by-ref */
			datum = PointerGetDatum(tp + off);

			/*
			 * The password probably shouldn't ever be out-of-line toasted; if
			 * it is, ignore it, since we can't handle that in startup mode.
			 */
			if (VARATT_IS_EXTERNAL(DatumGetPointer(datum)))
				auth_info[curr_role].rolpassword = pstrdup("");
			else
				auth_info[curr_role].rolpassword = DatumGetCString(DirectFunctionCall1(textout, datum));

			/* assume passwd has attlen -1 */
			off = att_addlength(off, -1, PointerGetDatum(tp + off));
		}

		if (HeapTupleHasNulls(tuple) &&
			att_isnull(Anum_pg_authid_rolvaliduntil - 1, bp))
		{
			/* rolvaliduntil is null, emit as an empty string */
			auth_info[curr_role].rolvaliduntil = pstrdup("");
		}
		else
		{
			/*
			 * rolvaliduntil is timestamptz, which we assume is double
			 * alignment and pass-by-value.
			 */
			off = att_align(off, 'd');
			datum = fetch_att(tp + off, true, sizeof(TimestampTz));
			auth_info[curr_role].rolvaliduntil = DatumGetCString(DirectFunctionCall1(timestamptz_out, datum));
		}

		/*
		 * Check for illegal characters in the user name and password.
		 */
		if (!name_okay(auth_info[curr_role].rolname))
		{
			ereport(LOG,
					(errmsg("invalid role name \"%s\"",
							auth_info[curr_role].rolname)));
			continue;
		}
		if (!name_okay(auth_info[curr_role].rolpassword))
		{
			ereport(LOG,
					(errmsg("invalid role password \"%s\"",
							auth_info[curr_role].rolpassword)));
			continue;
		}

		curr_role++;
		total_roles++;
	}
	heap_endscan(scan);

	*auth_info_out = auth_info;
	*total_roles_out = total_roles;
}
Exemple #18
0
/*
 * brin_deconstruct_tuple
 *		Guts of attribute extraction from an on-disk BRIN tuple.
 *
 * Its arguments are:
 *	brdesc		BRIN descriptor for the stored tuple
 *	tp			pointer to the tuple data area
 *	nullbits	pointer to the tuple nulls bitmask
 *	nulls		"has nulls" bit in tuple infomask
 *	values		output values, array of size brdesc->bd_totalstored
 *	allnulls	output "allnulls", size brdesc->bd_tupdesc->natts
 *	hasnulls	output "hasnulls", size brdesc->bd_tupdesc->natts
 *
 * Output arrays must have been allocated by caller.
 */
static inline void
brin_deconstruct_tuple(BrinDesc *brdesc,
					   char *tp, bits8 *nullbits, bool nulls,
					   Datum *values, bool *allnulls, bool *hasnulls)
{
	int			attnum;
	int			stored;
	TupleDesc	diskdsc;
	long		off;

	/*
	 * First iterate to natts to obtain both null flags for each attribute.
	 * Note that we reverse the sense of the att_isnull test, because we store
	 * 1 for a null value (rather than a 1 for a not null value as is the
	 * att_isnull convention used elsewhere.)  See brin_form_tuple.
	 */
	for (attnum = 0; attnum < brdesc->bd_tupdesc->natts; attnum++)
	{
		/*
		 * the "all nulls" bit means that all values in the page range for
		 * this column are nulls.  Therefore there are no values in the tuple
		 * data area.
		 */
		allnulls[attnum] = nulls && !att_isnull(attnum, nullbits);

		/*
		 * the "has nulls" bit means that some tuples have nulls, but others
		 * have not-null values.  Therefore we know the tuple contains data
		 * for this column.
		 *
		 * The hasnulls bits follow the allnulls bits in the same bitmask.
		 */
		hasnulls[attnum] =
			nulls && !att_isnull(brdesc->bd_tupdesc->natts + attnum, nullbits);
	}

	/*
	 * Iterate to obtain each attribute's stored values.  Note that since we
	 * may reuse attribute entries for more than one column, we cannot cache
	 * offsets here.
	 */
	diskdsc = brtuple_disk_tupdesc(brdesc);
	stored = 0;
	off = 0;
	for (attnum = 0; attnum < brdesc->bd_tupdesc->natts; attnum++)
	{
		int			datumno;

		if (allnulls[attnum])
		{
			stored += brdesc->bd_info[attnum]->oi_nstored;
			continue;
		}

		for (datumno = 0;
			 datumno < brdesc->bd_info[attnum]->oi_nstored;
			 datumno++)
		{
			Form_pg_attribute thisatt = TupleDescAttr(diskdsc, stored);

			if (thisatt->attlen == -1)
			{
				off = att_align_pointer(off, thisatt->attalign, -1,
										tp + off);
			}
			else
			{
				/* not varlena, so safe to use att_align_nominal */
				off = att_align_nominal(off, thisatt->attalign);
			}

			values[stored++] = fetchatt(thisatt, tp + off);

			off = att_addlength_pointer(off, thisatt->attlen, tp + off);
		}
	}
}
Exemple #19
0
/*
 * slot_deform_tuple
 *		Given a TupleTableSlot, extract data from the slot's physical tuple
 *		into its Datum/isnull arrays.  Data is extracted up through the
 *		natts'th column (caller must ensure this is a legal column number).
 *
 *		This is essentially an incremental version of heap_deform_tuple:
 *		on each call we extract attributes up to the one needed, without
 *		re-computing information about previously extracted attributes.
 *		slot->tts_nvalid is the number of attributes already extracted.
 */
static void
slot_deform_tuple(TupleTableSlot *slot, int natts)
{
	HeapTuple	tuple = TupGetHeapTuple(slot); 
	TupleDesc	tupleDesc = slot->tts_tupleDescriptor;
	Datum	   *values = slot->PRIVATE_tts_values;
	bool	   *isnull = slot->PRIVATE_tts_isnull;
	HeapTupleHeader tup = tuple->t_data;
	bool		hasnulls = HeapTupleHasNulls(tuple);
	Form_pg_attribute *att = tupleDesc->attrs;
	int			attnum;
	char	   *tp;				/* ptr to tuple data */
	long		off;			/* offset in tuple data */
	bits8	   *bp = tup->t_bits;		/* ptr to null bitmap in tuple */
	bool		slow;			/* can we use/set attcacheoff? */

	/*
	 * Check whether the first call for this tuple, and initialize or restore
	 * loop state.
	 */
	attnum = slot->PRIVATE_tts_nvalid;
	if (attnum == 0)
	{
		/* Start from the first attribute */
		off = 0;
		slow = false;
	}
	else
	{
		/* Restore state from previous execution */
		off = slot->PRIVATE_tts_off;
		slow = slot->PRIVATE_tts_slow;
	}

	tp = (char *) tup + tup->t_hoff;

	for (; attnum < natts; attnum++)
	{
		Form_pg_attribute thisatt = att[attnum];

		if (hasnulls && att_isnull(attnum, bp))
		{
			values[attnum] = (Datum) 0;
			isnull[attnum] = true;
			slow = true;		/* can't use attcacheoff anymore */
			continue;
		}

		isnull[attnum] = false;

		if (!slow && thisatt->attcacheoff >= 0)
			off = thisatt->attcacheoff;
		else
		{
			/* if it's a varlena it may or may not be aligned, so check for
			 * something that looks like a padding byte before aligning. If
			 * we're already aligned it may be the leading byte of a 4-byte
			 * header but then the att_align is harmless. Don't bother looking
			 * if it's not a varlena though.*/
			if (thisatt->attlen != -1 || !tp[off])
				off = att_align(off, thisatt->attalign);

			if (!slow && thisatt->attlen != -1)
				thisatt->attcacheoff = off;
		}
		if (!slow && thisatt->attlen < 0)
			slow = true;

		values[attnum] = fetchatt(thisatt, tp + off);

		off = att_addlength(off, thisatt->attlen, PointerGetDatum(tp + off));
	}

	/*
	 * Save state for next execution
	 */
	slot->PRIVATE_tts_nvalid = attnum;
	slot->PRIVATE_tts_off = off;
	slot->PRIVATE_tts_slow = slow;
}