/**********************************************************************//**
Reads from an undo log record a stored column value.
@return remaining part of undo log record after reading these values */
static
byte*
trx_undo_rec_get_col_val(
/*=====================*/
byte* ptr, /*!< in: pointer to remaining part of undo log record */
byte** field, /*!< out: pointer to stored field */
ulint* len, /*!< out: length of the field, or UNIV_SQL_NULL */
ulint* orig_len)/*!< out: original length of the locally
stored part of an externally stored column, or 0 */
{
*len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*len);
*orig_len = 0;
switch (*len) {
case UNIV_SQL_NULL:
*field = NULL;
break;
case UNIV_EXTERN_STORAGE_FIELD:
*orig_len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*orig_len);
*len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*len);
*field = ptr;
ptr += *len;
ut_ad(*orig_len >= BTR_EXTERN_FIELD_REF_SIZE);
ut_ad(*len > *orig_len);
/* @see dtuple_convert_big_rec() */
ut_ad(*len >= BTR_EXTERN_FIELD_REF_SIZE * 2);
/* we do not have access to index->table here
ut_ad(dict_table_get_format(index->table) >= DICT_TF_FORMAT_ZIP
|| *len >= REC_MAX_INDEX_COL_LEN
+ BTR_EXTERN_FIELD_REF_SIZE);
*/
*len += UNIV_EXTERN_STORAGE_FIELD;
break;
default:
*field = ptr;
if (*len >= UNIV_EXTERN_STORAGE_FIELD) {
ptr += *len - UNIV_EXTERN_STORAGE_FIELD;
} else {
ptr += *len;
}
}
return(ptr);
}
/**************************************************************************
Reads from an undo log record a stored column value. */
static
byte*
trx_undo_rec_get_col_val(
/*=====================*/
/* out: remaining part of undo log record after
reading these values */
byte* ptr, /* in: pointer to remaining part of undo log record */
byte** field, /* out: pointer to stored field */
ulint* len) /* out: length of the field, or UNIV_SQL_NULL */
{
*len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*len);
*field = ptr;
if (*len != UNIV_SQL_NULL) {
if (*len >= UNIV_EXTERN_STORAGE_FIELD) {
ptr += (*len - UNIV_EXTERN_STORAGE_FIELD);
} else {
ptr += *len;
}
}
return(ptr);
}
/**********************************************************************//**
Reads from an undo log record a stored column value.
@return remaining part of undo log record after reading these values */
static
byte*
trx_undo_rec_get_col_val(
/*=====================*/
byte* ptr, /*!< in: pointer to remaining part of undo log record */
byte** field, /*!< out: pointer to stored field */
ulint* len, /*!< out: length of the field, or UNIV_SQL_NULL */
ulint* orig_len)/*!< out: original length of the locally
stored part of an externally stored column, or 0 */
{
*len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*len);
*orig_len = 0;
switch (*len) {
case UNIV_SQL_NULL:
*field = NULL;
break;
case UNIV_EXTERN_STORAGE_FIELD:
*orig_len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*orig_len);
*len = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*len);
*field = ptr;
ptr += *len;
ut_ad(*orig_len >= BTR_EXTERN_FIELD_REF_SIZE);
ut_ad(*len > *orig_len);
ut_ad(*len >= REC_MAX_INDEX_COL_LEN
+ BTR_EXTERN_FIELD_REF_SIZE);
*len += UNIV_EXTERN_STORAGE_FIELD;
break;
default:
*field = ptr;
if (*len >= UNIV_EXTERN_STORAGE_FIELD) {
ptr += *len - UNIV_EXTERN_STORAGE_FIELD;
} else {
ptr += *len;
}
}
return(ptr);
}
/**********************************************************************//**
Reads from an update undo log record a stored field number.
@return remaining part of undo log record after reading this value */
UNIV_INLINE
byte*
trx_undo_update_rec_get_field_no(
/*=============================*/
byte* ptr, /*!< in: pointer to remaining part of undo log record */
ulint* field_no)/*!< out: field number */
{
*field_no = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*field_no);
return(ptr);
}
/**********************************************************************//**
Reads from an update undo log record the number of updated fields.
@return remaining part of undo log record after reading this value */
UNIV_INLINE
byte*
trx_undo_update_rec_get_n_upd_fields(
/*=================================*/
byte* ptr, /*!< in: pointer to remaining part of undo log record */
ulint* n) /*!< out: number of fields */
{
*n = mach_read_compressed(ptr);
ptr += mach_get_compressed_size(*n);
return(ptr);
}
byte*
mach_dulint_parse_compressed(
/*=========================*/
/* out: pointer to end of the stored field, NULL if
not complete */
byte* ptr, /* in: pointer to buffer from where to read */
byte* end_ptr,/* in: pointer to end of the buffer */
dulint* val) /* out: read value */
{
ulint high;
ulint low;
ulint size;
ut_ad(ptr && end_ptr && val);
if (end_ptr < ptr + 5) {
return(NULL);
}
high = mach_read_compressed(ptr);
size = mach_get_compressed_size(high);
ptr += size;
if (end_ptr < ptr + 4) {
return(NULL);
}
low = mach_read_from_4(ptr);
*val = ut_dulint_create(high, low);
return(ptr + 4);
}