mariadb/innobase/data/data0data.c

/************************************************************************
SQL data field and tuple

(c) 1994-1996 Innobase Oy

Created 5/30/1994 Heikki Tuuri
*************************************************************************/

#include "data0data.h"

#ifdef UNIV_NONINL
#include "data0data.ic"
#endif

#include "rem0rec.h"
#include "rem0cmp.h"
#include "page0page.h"
#include "dict0dict.h"
#include "btr0cur.h"

byte	data_error;	/* data pointers of tuple fields are initialized
			to point here for error checking */

#ifdef UNIV_DEBUG
ulint	data_dummy;	/* this is used to fool the compiler in
			dtuple_validate */
#endif /* UNIV_DEBUG */

/* Some non-inlined functions used in the MySQL interface: */
void 
dfield_set_data_noninline(
	dfield_t* 	field,	/* in: field */
	void*		data,	/* in: data */
	ulint		len)	/* in: length or UNIV_SQL_NULL */
{
	dfield_set_data(field, data, len);
}
void* 
dfield_get_data_noninline(
	dfield_t* field)	/* in: field */
{
	return(dfield_get_data(field));
}
ulint
dfield_get_len_noninline(
	dfield_t* field)	/* in: field */
{
	return(dfield_get_len(field));
}
ulint 
dtuple_get_n_fields_noninline(
	dtuple_t* 	tuple)	/* in: tuple */
{
	return(dtuple_get_n_fields(tuple));
}
dfield_t* 
dtuple_get_nth_field_noninline(
	dtuple_t* 	tuple,	/* in: tuple */
	ulint		n)	/* in: index of field */
{
	return(dtuple_get_nth_field(tuple, n));
}

/*************************************************************************
Tests if dfield data length and content is equal to the given. */

ibool
dfield_data_is_binary_equal(
/*========================*/
				/* out: TRUE if equal */
	dfield_t*	field,	/* in: field */
	ulint		len,	/* in: data length or UNIV_SQL_NULL */
	byte*		data)	/* in: data */
{
	if (len != field->len) {

		return(FALSE);
	}

	if (len == UNIV_SQL_NULL) {

		return(TRUE);
	}

	if (0 != ut_memcmp(field->data, data, len)) {
	    	
		return(FALSE);
	}

	return(TRUE);
}

/****************************************************************
Returns TRUE if lengths of two dtuples are equal and respective data fields
in them are equal when compared with collation in char fields (not as binary
strings). */

ibool
dtuple_datas_are_ordering_equal(
/*============================*/
				/* out: TRUE if length and fieds are equal
				when compared with cmp_data_data:
				NOTE: in character type fields some letters
				are identified with others! (collation) */
	dtuple_t*	tuple1,	/* in: tuple 1 */
	dtuple_t*	tuple2)	/* in: tuple 2 */
{
	dfield_t*	field1;
	dfield_t*	field2;
	ulint		n_fields;
	ulint		i;

	ut_ad(tuple1 && tuple2);
	ut_ad(tuple1->magic_n == DATA_TUPLE_MAGIC_N);
	ut_ad(tuple2->magic_n == DATA_TUPLE_MAGIC_N);
	ut_ad(dtuple_check_typed(tuple1));
	ut_ad(dtuple_check_typed(tuple2));

	n_fields = dtuple_get_n_fields(tuple1);

	if (n_fields != dtuple_get_n_fields(tuple2)) {

		return(FALSE);
	}
	
	for (i = 0; i < n_fields; i++) {

		field1 = dtuple_get_nth_field(tuple1, i);
		field2 = dtuple_get_nth_field(tuple2, i);

		if (0 != cmp_dfield_dfield(field1, field2)) {
		
			return(FALSE);
		}			
	}
	
	return(TRUE);
}

/*************************************************************************
Creates a dtuple for use in MySQL. */

dtuple_t*
dtuple_create_for_mysql(
/*====================*/
				/* out, own created dtuple */
	void** 	heap,    	/* out: created memory heap */
	ulint 	n_fields) 	/* in: number of fields */
{
  	*heap = (void*)mem_heap_create(500);
 
  	return(dtuple_create(*((mem_heap_t**)heap), n_fields));  
}

/*************************************************************************
Frees a dtuple used in MySQL. */

void
dtuple_free_for_mysql(
/*==================*/
	void*	heap) /* in: memory heap where tuple was created */
{
  	mem_heap_free((mem_heap_t*)heap);
}

/*************************************************************************
Sets number of fields used in a tuple. Normally this is set in
dtuple_create, but if you want later to set it smaller, you can use this. */ 

void
dtuple_set_n_fields(
/*================*/
	dtuple_t*	tuple,		/* in: tuple */
	ulint		n_fields)	/* in: number of fields */
{
	ut_ad(tuple);

	tuple->n_fields = n_fields;
	tuple->n_fields_cmp = n_fields;
}

/**************************************************************
Checks that a data field is typed. */
static
ibool
dfield_check_typed_no_assert(
/*=========================*/
				/* out: TRUE if ok */
	dfield_t*	field)	/* in: data field */
{
	if (dfield_get_type(field)->mtype > DATA_MYSQL
	    || dfield_get_type(field)->mtype < DATA_VARCHAR) {

		fprintf(stderr,
"InnoDB: Error: data field type %lu, len %lu\n",
			dfield_get_type(field)->mtype, dfield_get_len(field));
		return(FALSE);
	}

	return(TRUE);
}

/**************************************************************
Checks that a data tuple is typed. */

ibool
dtuple_check_typed_no_assert(
/*=========================*/
				/* out: TRUE if ok */
	dtuple_t*	tuple)	/* in: tuple */
{
	dfield_t*	field;
	ulint	 	i;
	
	if (dtuple_get_n_fields(tuple) > REC_MAX_N_FIELDS) {
		fprintf(stderr,
"InnoDB: Error: index entry has %lu fields\n",
			dtuple_get_n_fields(tuple));
	dump:
		fputs("InnoDB: Tuple contents: ", stderr);
		dtuple_print(stderr, tuple);
		putc('\n', stderr);

		return(FALSE);
	}

	for (i = 0; i < dtuple_get_n_fields(tuple); i++) {

		field = dtuple_get_nth_field(tuple, i);

		if (!dfield_check_typed_no_assert(field)) {
			goto dump;
		}
	}

	return(TRUE);
}

/**************************************************************
Checks that a data field is typed. Asserts an error if not. */

ibool
dfield_check_typed(
/*===============*/
				/* out: TRUE if ok */
	dfield_t*	field)	/* in: data field */
{
	if (dfield_get_type(field)->mtype > DATA_MYSQL
	    || dfield_get_type(field)->mtype < DATA_VARCHAR) {

		fprintf(stderr,
"InnoDB: Error: data field type %lu, len %lu\n",
			dfield_get_type(field)->mtype, dfield_get_len(field));

		ut_error;
	}

	return(TRUE);
}

/**************************************************************
Checks that a data tuple is typed. Asserts an error if not. */

ibool
dtuple_check_typed(
/*===============*/
				/* out: TRUE if ok */
	dtuple_t*	tuple)	/* in: tuple */
{
	dfield_t*	field;
	ulint	 	i;

	for (i = 0; i < dtuple_get_n_fields(tuple); i++) {

		field = dtuple_get_nth_field(tuple, i);

		ut_a(dfield_check_typed(field));
	}

	return(TRUE);
}

#ifdef UNIV_DEBUG
/**************************************************************
Validates the consistency of a tuple which must be complete, i.e,
all fields must have been set. */

ibool
dtuple_validate(
/*============*/
				/* out: TRUE if ok */
	dtuple_t*	tuple)	/* in: tuple */
{
	dfield_t*	field;
	byte*	 	data;
	ulint	 	n_fields;
	ulint	 	len;
	ulint	 	i;
	ulint	 	j;

	ut_ad(tuple->magic_n == DATA_TUPLE_MAGIC_N);

	n_fields = dtuple_get_n_fields(tuple);

	/* We dereference all the data of each field to test
	for memory traps */

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

		field = dtuple_get_nth_field(tuple, i);
		len = dfield_get_len(field);
	
		if (len != UNIV_SQL_NULL) {

			data = field->data;

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

				data_dummy  += *data; /* fool the compiler not
							to optimize out this
							code */
				data++;
			}
		}
	}

	ut_a(dtuple_check_typed(tuple));

	return(TRUE);
}
#endif /* UNIV_DEBUG */

/*****************************************************************
Pretty prints a dfield value according to its data type. */

void
dfield_print(
/*=========*/
	dfield_t*	dfield)	 /* in: dfield */
{
	byte*	data;
	ulint	len;
	ulint	mtype;
	ulint	i;

	len = dfield_get_len(dfield);
	data = dfield_get_data(dfield);

	if (len == UNIV_SQL_NULL) {
		fputs("NULL", stderr);

		return;
	}

	mtype = dtype_get_mtype(dfield_get_type(dfield));

	if ((mtype == DATA_CHAR) || (mtype == DATA_VARCHAR)) {
	
		for (i = 0; i < len; i++) {
			int	c = *data++;
			putc(isprint(c) ? c : ' ', stderr);
		}
	} else if (mtype == DATA_INT) {
		ut_a(len == 4); /* only works for 32-bit integers */
		fprintf(stderr, "%d", (int)mach_read_from_4(data));
	} else {
		ut_error;
	}
}

/*****************************************************************
Pretty prints a dfield value according to its data type. Also the hex string
is printed if a string contains non-printable characters. */ 

void
dfield_print_also_hex(
/*==================*/
	dfield_t*	dfield)	 /* in: dfield */
{
	byte*	data;
	ulint	len;
	ulint	mtype;
	ulint	i;
	ibool	print_also_hex;

	len = dfield_get_len(dfield);
	data = dfield_get_data(dfield);

	if (len == UNIV_SQL_NULL) {
		fputs("NULL", stderr);

		return;
	}

	mtype = dtype_get_mtype(dfield_get_type(dfield));

	if ((mtype == DATA_CHAR) || (mtype == DATA_VARCHAR)) {

		print_also_hex = FALSE;
	
		for (i = 0; i < len; i++) {
			int c = *data++;
			if (!isprint(c)) {
				print_also_hex = TRUE;
				c = ' ';
			}
			putc(c, stderr);
		}

		if (!print_also_hex) {

			return;
		}

		fputs(" Hex: ", stderr);
		
		data = dfield_get_data(dfield);
		
		for (i = 0; i < len; i++) {
			fprintf(stderr, "%02lx", (ulint)*data);

			data++;
		}
	} else if (mtype == DATA_INT) {
		ut_a(len == 4); /* only works for 32-bit integers */
		fprintf(stderr, "%d", (int)mach_read_from_4(data));
	} else {
		ut_error;
	}
}

/**************************************************************
The following function prints the contents of a tuple. */

void
dtuple_print(
/*=========*/
	FILE*		f,	/* in: output stream */
	dtuple_t*	tuple)	/* in: tuple */
{
	dfield_t*	field;
	ulint		n_fields;
	ulint		i;

	n_fields = dtuple_get_n_fields(tuple);

	fprintf(f, "DATA TUPLE: %lu fields;\n", n_fields);

	for (i = 0; i < n_fields; i++) {
		fprintf(f, " %lu:", i);

		field = dtuple_get_nth_field(tuple, i);
		
		if (field->len != UNIV_SQL_NULL) {
			ut_print_buf(f, field->data, field->len);
		} else {
			fputs(" SQL NULL", f);
		}

		putc(';', f);
	}

	putc('\n', f);
	ut_ad(dtuple_validate(tuple));
}

/******************************************************************
Moves parts of long fields in entry to the big record vector so that
the size of tuple drops below the maximum record size allowed in the
database. Moves data only from those fields which are not necessary
to determine uniquely the insertion place of the tuple in the index. */

big_rec_t*
dtuple_convert_big_rec(
/*===================*/
				/* out, own: created big record vector,
				NULL if we are not able to shorten
				the entry enough, i.e., if there are
				too many short fields in entry */
	dict_index_t*	index,	/* in: index */
	dtuple_t*	entry,	/* in: index entry */
	ulint*		ext_vec,/* in: array of externally stored fields,
				or NULL: if a field already is externally
				stored, then we cannot move it to the vector
				this function returns */
	ulint		n_ext_vec)/* in: number of elements is ext_vec */
{
	mem_heap_t*	heap;
	big_rec_t*	vector;
	dfield_t*	dfield;
	ulint		size;
	ulint		n_fields;
	ulint		longest;
	ulint		longest_i		= ULINT_MAX;
	ibool		is_externally_stored;
	ulint		i;
	ulint		j;
	
	ut_a(dtuple_check_typed_no_assert(entry));

	size = rec_get_converted_size(entry);

	if (size > 1000000000) {
		fprintf(stderr,
"InnoDB: Warning: tuple size very big: %lu\n", size);
		fputs("InnoDB: Tuple contents: ", stderr);
		dtuple_print(stderr, entry);
		putc('\n', stderr);
	}

	heap = mem_heap_create(size + dtuple_get_n_fields(entry)
					* sizeof(big_rec_field_t) + 1000);

	vector = mem_heap_alloc(heap, sizeof(big_rec_t));

	vector->heap = heap;
	vector->fields = mem_heap_alloc(heap, dtuple_get_n_fields(entry)
					* sizeof(big_rec_field_t));

	/* Decide which fields to shorten: the algorithm is to look for
	the longest field whose type is DATA_BLOB */

	n_fields = 0;

	while ((rec_get_converted_size(entry)
					>= page_get_free_space_of_empty() / 2)
	       || rec_get_converted_size(entry) >= REC_MAX_DATA_SIZE) {

		longest = 0;
		for (i = dict_index_get_n_unique_in_tree(index);
				i < dtuple_get_n_fields(entry); i++) {

			/* Skip over fields which already are externally
			stored */

			is_externally_stored = FALSE;

			if (ext_vec) {
				for (j = 0; j < n_ext_vec; j++) {
					if (ext_vec[j] == i) {
						is_externally_stored = TRUE;
					}
				}
			}
				
			if (!is_externally_stored
			    && dict_index_get_nth_type(index, i)->mtype
			       == DATA_BLOB) {

				dfield = dtuple_get_nth_field(entry, i);

				if (dfield->len != UNIV_SQL_NULL &&
			        		dfield->len > longest) {

			        	longest = dfield->len;

			        	longest_i = i;
				}
			}
		}
	
		/* We do not store externally fields which are smaller than
		DICT_MAX_COL_PREFIX_LEN */

		ut_a(DICT_MAX_COL_PREFIX_LEN > REC_1BYTE_OFFS_LIMIT);

		if (longest < BTR_EXTERN_FIELD_REF_SIZE + 10
						+ DICT_MAX_COL_PREFIX_LEN) {
			/* Cannot shorten more */

			mem_heap_free(heap);

			return(NULL);
		}

		/* Move data from field longest_i to big rec vector;
		we do not let data size of the remaining entry
		drop below 128 which is the limit for the 2-byte
		offset storage format in a physical record. This
		we accomplish by storing 128 bytes of data in entry
		itself, and only the remaining part to big rec vec.

		We store the first bytes locally to the record. Then
		we can calculate all ordering fields in all indexes
		from locally stored data. */

		dfield = dtuple_get_nth_field(entry, longest_i);
		vector->fields[n_fields].field_no = longest_i;

		ut_a(dfield->len > DICT_MAX_COL_PREFIX_LEN);
		
		vector->fields[n_fields].len = dfield->len
						- DICT_MAX_COL_PREFIX_LEN;

		vector->fields[n_fields].data = mem_heap_alloc(heap,
						vector->fields[n_fields].len);

		/* Copy data (from the end of field) to big rec vector */

		ut_memcpy(vector->fields[n_fields].data,
				((byte*)dfield->data) + dfield->len
						- vector->fields[n_fields].len,
				vector->fields[n_fields].len);
		dfield->len = dfield->len - vector->fields[n_fields].len
						+ BTR_EXTERN_FIELD_REF_SIZE;

		/* Set the extern field reference in dfield to zero */
		memset(((byte*)dfield->data)
			+ dfield->len - BTR_EXTERN_FIELD_REF_SIZE,
					0, BTR_EXTERN_FIELD_REF_SIZE);
		n_fields++;
	}	

	vector->n_fields = n_fields;
	return(vector);
}

/******************************************************************
Puts back to entry the data stored in vector. Note that to ensure the
fields in entry can accommodate the data, vector must have been created
from entry with dtuple_convert_big_rec. */

void
dtuple_convert_back_big_rec(
/*========================*/
	dict_index_t*	index __attribute__((unused)),	/* in: index */
	dtuple_t*	entry,	/* in: entry whose data was put to vector */
	big_rec_t*	vector)	/* in, own: big rec vector; it is
				freed in this function */
{
	dfield_t*	dfield;
	ulint		i;	

	for (i = 0; i < vector->n_fields; i++) {
	
		dfield = dtuple_get_nth_field(entry,
						vector->fields[i].field_no);
		/* Copy data from big rec vector */

		ut_memcpy(((byte*)dfield->data)
				+ dfield->len - BTR_EXTERN_FIELD_REF_SIZE,
			  vector->fields[i].data,
		          vector->fields[i].len);
		dfield->len = dfield->len + vector->fields[i].len
						- BTR_EXTERN_FIELD_REF_SIZE;
	}	

	mem_heap_free(vector->heap);
}

/******************************************************************
Frees the memory in a big rec vector. */

void
dtuple_big_rec_free(
/*================*/
	big_rec_t*	vector)	/* in, own: big rec vector; it is
				freed in this function */
{
	mem_heap_free(vector->heap);
}