~drizzle-trunk/drizzle/development

/************************************************************************

SQL data field and tuple

(c) 1994-1996 Innobase Oy

Created 5/30/1994 Heikki Tuuri

*************************************************************************/

#include "mem0mem.h"

#include "ut0rnd.h"

#ifdef UNIV_DEBUG

extern byte data_error;

#endif /* UNIV_DEBUG */

/*************************************************************************

Gets pointer to the type struct of SQL data field. */

UNIV_INLINE

dtype_t*

dfield_get_type(

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

				/* out: pointer to the type struct */

	dfield_t*	field)	/* in: SQL data field */

{

	ut_ad(field);

	return(&(field->type));

}

/*************************************************************************

Sets the type struct of SQL data field. */

UNIV_INLINE

void

dfield_set_type(

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

	dfield_t*	field,	/* in: SQL data field */

	dtype_t*	type)	/* in: pointer to data type struct */

{

	ut_ad(field && type);

	field->type = *type;

}

/*************************************************************************

Gets pointer to the data in a field. */

UNIV_INLINE

void*

dfield_get_data(

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

				/* out: pointer to data */

	dfield_t* field)	/* in: field */

{

	ut_ad(field);

	ut_ad((field->len == UNIV_SQL_NULL)

	      || (field->data != &data_error));

	return(field->data);

}

/*************************************************************************

Gets length of field data. */

UNIV_INLINE

ulint

dfield_get_len(

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

				/* out: length of data; UNIV_SQL_NULL if

				SQL null data */

	dfield_t* field)	/* in: field */

{

	ut_ad(field);

	ut_ad((field->len == UNIV_SQL_NULL)

	      || (field->data != &data_error));

	return(field->len);

}

/*************************************************************************

Sets length in a field. */

UNIV_INLINE

void

dfield_set_len(

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

	dfield_t*	field,	/* in: field */

	ulint		len)	/* in: length or UNIV_SQL_NULL */

{

	ut_ad(field);

	field->len = len;

}

/*************************************************************************

Sets pointer to the data and length in a field. */

UNIV_INLINE

void

dfield_set_data(

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

	dfield_t*	field,	/* in: field */

	const void*	data,	/* in: data */

	ulint		len)	/* in: length or UNIV_SQL_NULL */

{

	ut_ad(field);

	field->data = (void*) data;

	field->len = len;

}

/*************************************************************************

Copies the data and len fields. */

UNIV_INLINE

void

dfield_copy_data(

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

	dfield_t*	field1,	/* in: field to copy to */

	dfield_t*	field2)	/* in: field to copy from */

{

	ut_ad(field1 && field2);

	field1->data = field2->data;

	field1->len = field2->len;

}

/*************************************************************************

Copies a data field to another. */

UNIV_INLINE

void

dfield_copy(

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

	dfield_t*	field1,	/* in: field to copy to */

	dfield_t*	field2)	/* in: field to copy from */

{

	*field1 = *field2;

}

/*************************************************************************

Tests if data length and content is equal for two dfields. */

UNIV_INLINE

ibool

dfield_datas_are_binary_equal(

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

				/* out: TRUE if equal */

	dfield_t*	field1,	/* in: field */

	dfield_t*	field2)	/* in: field */

{

	ulint	len;

	len = field1->len;

	if ((len != field2->len)

	    || ((len != UNIV_SQL_NULL)

		&& (0 != ut_memcmp(field1->data, field2->data,

				   len)))) {

		return(FALSE);

	}

	return(TRUE);

}

/*************************************************************************

Gets info bits in a data tuple. */

UNIV_INLINE

ulint

dtuple_get_info_bits(

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

				/* out: info bits */

	dtuple_t*	tuple)	/* in: tuple */

{

	ut_ad(tuple);

	return(tuple->info_bits);

}

/*************************************************************************

Sets info bits in a data tuple. */

UNIV_INLINE

void

dtuple_set_info_bits(

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

	dtuple_t*	tuple,		/* in: tuple */

	ulint		info_bits)	/* in: info bits */

{

	ut_ad(tuple);

	tuple->info_bits = info_bits;

}

/*************************************************************************

Gets number of fields used in record comparisons. */

UNIV_INLINE

ulint

dtuple_get_n_fields_cmp(

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

				/* out: number of fields used in comparisons

				in rem0cmp.* */

	dtuple_t*	tuple)	/* in: tuple */

{

	ut_ad(tuple);

	return(tuple->n_fields_cmp);

}

/*************************************************************************

Sets number of fields used in record comparisons. */

UNIV_INLINE

void

dtuple_set_n_fields_cmp(

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

	dtuple_t*	tuple,		/* in: tuple */

	ulint		n_fields_cmp)	/* in: number of fields used in

					comparisons in rem0cmp.* */

{

	ut_ad(tuple);

	ut_ad(n_fields_cmp <= tuple->n_fields);

	tuple->n_fields_cmp = n_fields_cmp;

}

/*************************************************************************

Gets number of fields in a data tuple. */

UNIV_INLINE

ulint

dtuple_get_n_fields(

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

				/* out: number of fields */

	dtuple_t*	tuple)	/* in: tuple */

{

	ut_ad(tuple);

	return(tuple->n_fields);

}

/*************************************************************************

Gets nth field of a tuple. */

UNIV_INLINE

dfield_t*

dtuple_get_nth_field(

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

				/* out: nth field */

	dtuple_t*	tuple,	/* in: tuple */

	ulint		n)	/* in: index of field */

{

	ut_ad(tuple);

	ut_ad(n < tuple->n_fields);

	return(tuple->fields + n);

}

/**************************************************************

Creates a data tuple to a memory heap. The default value for number

of fields used in record comparisons for this tuple is n_fields. */

UNIV_INLINE

dtuple_t*

dtuple_create(

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

				/* out, own: created tuple */

	mem_heap_t*	heap,	/* in: memory heap where the tuple

				is created */

	ulint		n_fields) /* in: number of fields */

{

	dtuple_t*	tuple;

	ut_ad(heap);

	tuple = (dtuple_t*) mem_heap_alloc(heap, sizeof(dtuple_t)

					   + n_fields * sizeof(dfield_t));

	tuple->info_bits = 0;

	tuple->n_fields = n_fields;

	tuple->n_fields_cmp = n_fields;

	tuple->fields = (dfield_t*)(((byte*)tuple) + sizeof(dtuple_t));

#ifdef UNIV_DEBUG

	tuple->magic_n = DATA_TUPLE_MAGIC_N;

	{	/* In the debug version, initialize fields to an error value */

		ulint	i;

		for (i = 0; i < n_fields; i++) {

			(tuple->fields + i)->data = &data_error;

			dfield_get_type(tuple->fields + i)->mtype = DATA_ERROR;

		}

	}

#endif

	return(tuple);

}

/**************************************************************

The following function returns the sum of data lengths of a tuple. The space

occupied by the field structs or the tuple struct is not counted. Neither

is possible space in externally stored parts of the field. */

UNIV_INLINE

ulint

dtuple_get_data_size(

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

				/* out: sum of data lengths */

	dtuple_t*	tuple)	/* in: typed data tuple */

{

	dfield_t*	field;

	ulint		n_fields;

	ulint		len;

	ulint		i;

	ulint		sum	= 0;

	ut_ad(tuple);

	ut_ad(dtuple_check_typed(tuple));

	ut_ad(tuple->magic_n == DATA_TUPLE_MAGIC_N);

	n_fields = tuple->n_fields;

	for (i = 0; i < n_fields; i++) {

		field = dtuple_get_nth_field(tuple,  i);

		len = dfield_get_len(field);

		if (len == UNIV_SQL_NULL) {

			len = dtype_get_sql_null_size(dfield_get_type(field));

		}

		sum += len;

	}

	return(sum);

}

/***********************************************************************

Sets types of fields binary in a tuple. */

UNIV_INLINE

void

dtuple_set_types_binary(

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

	dtuple_t*	tuple,	/* in: data tuple */

	ulint		n)	/* in: number of fields to set */

{

	dtype_t*	dfield_type;

	ulint		i;

	for (i = 0; i < n; i++) {

		dfield_type = dfield_get_type(dtuple_get_nth_field(tuple, i));

		dtype_set(dfield_type, DATA_BINARY, 0, 0);

	}

}

/****************************************************************

Folds a prefix given as the number of fields of a tuple. */

UNIV_INLINE

ulint

dtuple_fold(

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

				/* out: the folded value */

	dtuple_t*	tuple,	/* in: the tuple */

	ulint		n_fields,/* in: number of complete fields to fold */

	ulint		n_bytes,/* in: number of bytes to fold in an

				incomplete last field */

	dulint		tree_id)/* in: index tree id */

{

	dfield_t*	field;

	ulint		i;

	byte*		data;

	ulint		len;

	ulint		fold;

	ut_ad(tuple);

	ut_ad(tuple->magic_n == DATA_TUPLE_MAGIC_N);

	ut_ad(dtuple_check_typed(tuple));

	fold = ut_fold_dulint(tree_id);

	for (i = 0; i < n_fields; i++) {

		field = dtuple_get_nth_field(tuple, i);

		data = (byte*) dfield_get_data(field);

		len = dfield_get_len(field);

		if (len != UNIV_SQL_NULL) {

			fold = ut_fold_ulint_pair(fold,

						  ut_fold_binary(data, len));

		}

	}

	if (n_bytes > 0) {

		field = dtuple_get_nth_field(tuple, i);

		data = (byte*) dfield_get_data(field);

		len = dfield_get_len(field);

		if (len != UNIV_SQL_NULL) {

			if (len > n_bytes) {

				len = n_bytes;

			}

			fold = ut_fold_ulint_pair(fold,

						  ut_fold_binary(data, len));

		}

	}

	return(fold);

}

/**************************************************************************

Writes an SQL null field full of zeros. */

UNIV_INLINE

void

data_write_sql_null(

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

	byte*	data,	/* in: pointer to a buffer of size len */

	ulint	len)	/* in: SQL null size in bytes */

{

	ulint	j;

	for (j = 0; j < len; j++) {

		data[j] = '\0';

	}

}

/**************************************************************************

Checks if a dtuple contains an SQL null value. */

UNIV_INLINE

ibool

dtuple_contains_null(

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

				/* out: TRUE if some field is SQL null */

	dtuple_t*	tuple)	/* in: dtuple */

{

	ulint	n;

	ulint	i;

	n = dtuple_get_n_fields(tuple);

	for (i = 0; i < n; i++) {

		if (dfield_get_len(dtuple_get_nth_field(tuple, i))

		    == UNIV_SQL_NULL) {

			return(TRUE);

		}

	}

	return(FALSE);

}