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Commit 0d3f926a authored by unknown's avatar unknown
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WL#2735: Refactor replication 

Factoring out pack_row() and unpack_row() into new files
rpl_record.{cc,h}.


libmysqld/Makefile.am:
  Adding file rpl_record.cc
sql/CMakeLists.txt:
  Adding file rpl_record.cc
sql/Makefile.am:
  Adding file rpl_record.cc and rpl_record.h
sql/log_event.cc:
  Moving implementation of unpack_row() into "rpl_record.cc".
  Adding inclusion of header file "rpl_record.h".
sql/log_event_old.cc:
  Signature of do_prepare_row() changed.
sql/log_event_old.h:
  Adding copyright.
sql/rpl_record_old.cc:
  Signature of do_prepare_row() changed.
sql/rpl_record_old.h:
  Adding copyright.
  Signature of do_prepare_row() changed.
sql/sql_class.cc:
  Moving implementation THD::pack_row() into "rpl_record.cc" and rewriting
  it to be a global function.
  Adding inclusion of header file "rpl_record.h".
sql/sql_class.h:
  Removing pack_row() as THD member function.
sql/rpl_record.cc:
  New BitKeeper file ``sql/rpl_record.cc''
sql/rpl_record.h:
  New BitKeeper file ``sql/rpl_record.h''
parent dc125bb3
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Showing with 368 additions and 282 deletions
libmysqld/Makefile.am
View file @ 0d3f926a
......@@ -54,7 +54,7 @@ sqlsources = derror.cc field.cc field_conv.cc strfunc.cc filesort.cc \
item_geofunc.cc item_subselect.cc item_row.cc\
item_xmlfunc.cc \
key.cc lock.cc log.cc sql_state.c \
log_event.cc \
log_event.cc rpl_record.cc \
log_event_old.cc rpl_record_old.cc \
protocol.cc net_serv.cc opt_range.cc \
opt_sum.cc procedure.cc records.cc sql_acl.cc \
......
sql/CMakeLists.txt
View file @ 0d3f926a
......@@ -47,7 +47,8 @@ ADD_EXECUTABLE(mysqld ../sql-common/client.c derror.cc des_key_file.cc
hostname.cc init.cc item.cc item_buff.cc item_cmpfunc.cc
item_create.cc item_func.cc item_geofunc.cc item_row.cc
item_strfunc.cc item_subselect.cc item_sum.cc item_timefunc.cc
key.cc log.cc lock.cc log_event.cc message.rc
key.cc log.cc lock.cc message.rc
log_event.cc rpl_record.cc
log_event_old.cc rpl_record_old.cc
message.h mf_iocache.cc my_decimal.cc ../sql-common/my_time.c
mysqld.cc net_serv.cc
......
sql/Makefile.am
View file @ 0d3f926a
......@@ -57,8 +57,8 @@ noinst_HEADERS = item.h item_func.h item_sum.h item_cmpfunc.h \
log.h sql_show.h rpl_rli.h rpl_mi.h \
sql_select.h structs.h table.h sql_udf.h hash_filo.h \
lex.h lex_symbol.h sql_acl.h sql_crypt.h \
log_event.h sql_repl.h slave.h rpl_filter.h \
rpl_injector.h \
sql_repl.h slave.h rpl_filter.h rpl_injector.h \
log_event.h rpl_record.h \
log_event_old.h rpl_record_old.h \
stacktrace.h sql_sort.h sql_cache.h set_var.h \
spatial.h gstream.h client_settings.h tzfile.h \
......@@ -87,8 +87,9 @@ mysqld_SOURCES = sql_lex.cc sql_handler.cc sql_partition.cc \
sql_prepare.cc sql_error.cc sql_locale.cc \
sql_update.cc sql_delete.cc uniques.cc sql_do.cc \
procedure.cc sql_test.cc \
log.cc log_event.cc init.cc derror.cc sql_acl.cc \
log.cc init.cc derror.cc sql_acl.cc \
unireg.cc des_key_file.cc \
log_event.cc rpl_record.cc \
log_event_old.cc rpl_record_old.cc \
discover.cc time.cc opt_range.cc opt_sum.cc \
records.cc filesort.cc handler.cc \
......
sql/log_event.cc
View file @ 0d3f926a
......@@ -26,6 +26,7 @@
#include "rpl_mi.h"
#include "rpl_filter.h"
#include "rpl_utility.h"
#include "rpl_record.h"
#include <my_dir.h>
#endif /* MYSQL_CLIENT */
#include <base64.h>
......@@ -5811,163 +5812,6 @@ int Rows_log_event::do_add_row_data(byte *const row_data,
#endif
#if !defined(MYSQL_CLIENT) && defined(HAVE_REPLICATION)
/*
Unpack a row into table->record[0].
SYNOPSIS
unpack_row()
rli Relay log info
table Table to unpack into
colcnt Number of columns to read from record
row Packed row data
cols Pointer to columns data to fill in
row_end Pointer to variable that will hold the value of the
one-after-end position for the row
master_reclength
Pointer to variable that will be set to the length of the
record on the master side
rw_set Pointer to bitmap that holds either the read_set or the
write_set of the table
DESCRIPTION
The function will always unpack into the table->record[0]
record. This is because there are too many dependencies on
where the various member functions of Field and subclasses
expect to write.
The row is assumed to only consist of the fields for which the
bitset represented by 'arr' and 'bits'; the other parts of the
record are left alone.
At most 'colcnt' columns are read: if the table is larger than
that, the remaining fields are not filled in.
RETURN VALUE
Error code, or zero if no error. The following error codes can
be returned:
ER_NO_DEFAULT_FOR_FIELD
Returned if one of the fields existing on the slave but not on
the master does not have a default value (and isn't nullable)
*/
static int
unpack_row(RELAY_LOG_INFO const *rli,
TABLE *table, uint const colcnt,
char const *const row_data, MY_BITMAP const *cols,
char const **const row_end, ulong *const master_reclength,
MY_BITMAP* const rw_set, Log_event_type const event_type)
{
DBUG_ENTER("unpack_row");
DBUG_ASSERT(row_data);
my_size_t const master_null_byte_count= (bitmap_bits_set(cols) + 7) / 8;
int error= 0;
char const *null_ptr= row_data;
char const *pack_ptr= row_data + master_null_byte_count;
bitmap_clear_all(rw_set);
empty_record(table);
Field **const begin_ptr = table->field;
Field **field_ptr;
Field **const end_ptr= begin_ptr + colcnt;
DBUG_ASSERT(null_ptr < row_data + master_null_byte_count);
// Mask to mask out the correct bit among the null bits
unsigned int null_mask= 1U;
// The "current" null bits
unsigned int null_bits= *null_ptr++;
for (field_ptr= begin_ptr ; field_ptr < end_ptr ; ++field_ptr)
{
Field *const f= *field_ptr;
/*
No need to bother about columns that does not exist: they have
gotten default values when being emptied above.
*/
if (bitmap_is_set(cols, field_ptr - begin_ptr))
{
if ((null_mask & 0xFF) == 0)
{
DBUG_ASSERT(null_ptr < row_data + master_null_byte_count);
null_mask= 1U;
null_bits= *null_ptr++;
}
DBUG_ASSERT(null_mask & 0xFF); // One of the 8 LSB should be set
/* Field...::unpack() cannot return 0 */
DBUG_ASSERT(pack_ptr != NULL);
if ((null_bits & null_mask) && f->maybe_null())
f->set_null();
else
{
f->set_notnull();
/*
We only unpack the field if it was non-null
*/
pack_ptr= f->unpack(f->ptr, pack_ptr);
}
bitmap_set_bit(rw_set, f->field_index);
null_mask <<= 1;
}
}
/*
We should now have read all the null bytes, otherwise something is
really wrong.
*/
DBUG_ASSERT(null_ptr == row_data + master_null_byte_count);
*row_end = pack_ptr;
if (master_reclength)
{
if (*field_ptr)
*master_reclength = (*field_ptr)->ptr - (char*) table->record[0];
else
*master_reclength = table->s->reclength;
}
/*
Set properties for remaining columns, if there are any. We let the
corresponding bit in the write_set be set, to write the value if
it was not there already. We iterate over all remaining columns,
even if there were an error, to get as many error messages as
possible. We are still able to return a pointer to the next row,
so redo that.
This generation of error messages is only relevant when inserting
new rows.
*/
for ( ; *field_ptr ; ++field_ptr)
{
uint32 const mask= NOT_NULL_FLAG | NO_DEFAULT_VALUE_FLAG;
Field *const f= *field_ptr;
if (event_type == WRITE_ROWS_EVENT &&
((*field_ptr)->flags & mask) == mask)
{
slave_print_msg(ERROR_LEVEL, rli, ER_NO_DEFAULT_FOR_FIELD,
"Field `%s` of table `%s`.`%s` "
"has no default value and cannot be NULL",
(*field_ptr)->field_name, table->s->db.str,
table->s->table_name.str);
error = ER_NO_DEFAULT_FOR_FIELD;
}
else
f->set_default();
}
DBUG_RETURN(error);
}
int Rows_log_event::do_apply_event(RELAY_LOG_INFO const *rli)
{
DBUG_ENTER("Rows_log_event::do_apply_event(st_relay_log_info*)");
......
sql/log_event_old.cc
View file @ 0d3f926a
......@@ -5,7 +5,8 @@
#if !defined(MYSQL_CLIENT) && defined(HAVE_REPLICATION)
int
Write_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
Write_rows_log_event_old::do_prepare_row(THD *thd,
RELAY_LOG_INFO const *rli,
TABLE *table,
char const *row_start,
char const **row_end)
......@@ -14,7 +15,8 @@ Write_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
DBUG_ASSERT(row_start && row_end);
int error;
error= unpack_row_old(rli, table, m_width, table->record[0],
error= unpack_row_old(const_cast<RELAY_LOG_INFO*>(rli),
table, m_width, table->record[0],
row_start, &m_cols, row_end, &m_master_reclength,
table->write_set, PRE_GA_WRITE_ROWS_EVENT);
bitmap_copy(table->read_set, table->write_set);
......@@ -23,7 +25,8 @@ Write_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
int
Delete_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
Delete_rows_log_event_old::do_prepare_row(THD *thd,
RELAY_LOG_INFO const *rli,
TABLE *table,
char const *row_start,
char const **row_end)
......@@ -36,7 +39,8 @@ Delete_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
*/
DBUG_ASSERT(table->s->fields >= m_width);
error= unpack_row_old(rli, table, m_width, table->record[0],
error= unpack_row_old(const_cast<RELAY_LOG_INFO*>(rli),
table, m_width, table->record[0],
row_start, &m_cols, row_end, &m_master_reclength,
table->read_set, PRE_GA_DELETE_ROWS_EVENT);
/*
......@@ -54,7 +58,8 @@ Delete_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
}
int Update_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
int Update_rows_log_event_old::do_prepare_row(THD *thd,
RELAY_LOG_INFO const *rli,
TABLE *table,
char const *row_start,
char const **row_end)
......@@ -68,12 +73,14 @@ int Update_rows_log_event_old::do_prepare_row(THD *thd, RELAY_LOG_INFO *rli,
DBUG_ASSERT(table->s->fields >= m_width);
/* record[0] is the before image for the update */
error= unpack_row_old(rli, table, m_width, table->record[0],
error= unpack_row_old(const_cast<RELAY_LOG_INFO*>(rli),
table, m_width, table->record[0],
row_start, &m_cols, row_end, &m_master_reclength,
table->read_set, PRE_GA_UPDATE_ROWS_EVENT);
row_start = *row_end;
/* m_after_image is the after image for the update */
error= unpack_row_old(rli, table, m_width, m_after_image,
error= unpack_row_old(const_cast<RELAY_LOG_INFO*>(rli),
table, m_width, m_after_image,
row_start, &m_cols, row_end, &m_master_reclength,
table->write_set, PRE_GA_UPDATE_ROWS_EVENT);
......
sql/log_event_old.h
View file @ 0d3f926a
/* Copyright 2007 MySQL AB. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifndef LOG_EVENT_OLD_H
#define LOG_EVENT_OLD_H
......
sql/rpl_record.cc 0 → 100644
View file @ 0d3f926a
/* Copyright 2007 MySQL AB. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#include "mysql_priv.h"
#include "rpl_record.h"
#include "slave.h" // Need to pull in slave_print_msg
/**
Pack a record of data for a table into a format suitable for
transfer via the binary log.
The format for a row in transfer with N fields is the following:
ceil(N/8) null bytes:
One null bit for every column *regardless of whether it can be
null or not*. This simplifies the decoding. Observe that the
number of null bits is equal to the number of set bits in the
@c cols bitmap. The number of null bytes is the smallest number
of bytes necessary to store the null bits.
Padding bits are 1.
N packets:
Each field is stored in packed format.
@param table Table describing the format of the record
@param cols Bitmap with a set bit for each column that should
be stored in the row
@param row_data Pointer to memory where row will be written
@param record Pointer to record that should be packed. It is
assumed that the pointer refers to either @c
record[0] or @c record[1], but no such check is
made since the code does not rely on that.
@return The number of bytes written at @c row_data.
*/
my_size_t
pack_row(TABLE *table, MY_BITMAP const* cols,
byte *const row_data, const byte *record)
{
Field **p_field= table->field, *field;
int const null_byte_count= (bitmap_bits_set(cols) + 7) / 8;
byte *pack_ptr = row_data + null_byte_count;
byte *null_ptr = row_data;
my_ptrdiff_t const rec_offset= record - table->record[0];
my_ptrdiff_t const def_offset= table->s->default_values - table->record[0];
/*
We write the null bits and the packed records using one pass
through all the fields. The null bytes are written little-endian,
i.e., the first fields are in the first byte.
*/
unsigned int null_bits= (1U << 8) - 1;
// Mask to mask out the correct but among the null bits
unsigned int null_mask= 1U;
for ( ; (field= *p_field) ; p_field++)
{
DBUG_PRINT("debug", ("null_mask=%d; null_ptr=%p; row_data=%p; null_byte_count=%d",
null_mask, null_ptr, row_data, null_byte_count));
if (bitmap_is_set(cols, p_field - table->field))
{
my_ptrdiff_t offset;
if (field->is_null(rec_offset))
{
offset= def_offset;
null_bits |= null_mask;
}
else
{
offset= rec_offset;
null_bits &= ~null_mask;
/*
We only store the data of the field if it is non-null
*/
pack_ptr= (byte*)field->pack((char *) pack_ptr, field->ptr + offset);
}
null_mask <<= 1;
if ((null_mask & 0xFF) == 0)
{
DBUG_ASSERT(null_ptr < row_data + null_byte_count);
null_mask = 1U;
*null_ptr++ = null_bits;
null_bits= (1U << 8) - 1;
}
}
}
/*
Write the last (partial) byte, if there is one
*/
if ((null_mask & 0xFF) > 1)
{
DBUG_ASSERT(null_ptr < row_data + null_byte_count);
*null_ptr++ = null_bits;
}
/*
The null pointer should now point to the first byte of the
packed data. If it doesn't, something is very wrong.
*/
DBUG_ASSERT(null_ptr == row_data + null_byte_count);
return static_cast<my_size_t>(pack_ptr - row_data);
}
/**
Unpack a row into @c table->record[0].
The function will always unpack into the @c table->record[0]
record. This is because there are too many dependencies on where
the various member functions of Field and subclasses expect to
write.
The row is assumed to only consist of the fields for which the
bitset represented by @c arr and @c bits; the other parts of the
record are left alone.
At most @c colcnt columns are read: if the table is larger than
that, the remaining fields are not filled in.
@param rli Relay log info
@param table Table to unpack into
@param colcnt Number of columns to read from record
@param row Packed row data
@param cols Pointer to columns data to fill in
@param row_end Pointer to variable that will hold the value of the
one-after-end position for the row
@param master_reclength
Pointer to variable that will be set to the length of the
record on the master side
@param rw_set Pointer to bitmap that holds either the read_set or the
write_set of the table
@retval 0 No error
@retval ER_NO_DEFAULT_FOR_FIELD
Returned if one of the fields existing on the slave but not on the
master does not have a default value (and isn't nullable)
*/
#ifdef HAVE_REPLICATION
int
unpack_row(RELAY_LOG_INFO const *rli,
TABLE *table, uint const colcnt,
char const *const row_data, MY_BITMAP const *cols,
char const **const row_end, ulong *const master_reclength,
MY_BITMAP* const rw_set, Log_event_type const event_type)
{
DBUG_ENTER("unpack_row");
DBUG_ASSERT(row_data);
my_size_t const master_null_byte_count= (bitmap_bits_set(cols) + 7) / 8;
int error= 0;
char const *null_ptr= row_data;
char const *pack_ptr= row_data + master_null_byte_count;
bitmap_clear_all(rw_set);
empty_record(table);
Field **const begin_ptr = table->field;
Field **field_ptr;
Field **const end_ptr= begin_ptr + colcnt;
DBUG_ASSERT(null_ptr < row_data + master_null_byte_count);
// Mask to mask out the correct bit among the null bits
unsigned int null_mask= 1U;
// The "current" null bits
unsigned int null_bits= *null_ptr++;
for (field_ptr= begin_ptr ; field_ptr < end_ptr ; ++field_ptr)
{
Field *const f= *field_ptr;
/*
No need to bother about columns that does not exist: they have
gotten default values when being emptied above.
*/
if (bitmap_is_set(cols, field_ptr - begin_ptr))
{
if ((null_mask & 0xFF) == 0)
{
DBUG_ASSERT(null_ptr < row_data + master_null_byte_count);
null_mask= 1U;
null_bits= *null_ptr++;
}
DBUG_ASSERT(null_mask & 0xFF); // One of the 8 LSB should be set
/* Field...::unpack() cannot return 0 */
DBUG_ASSERT(pack_ptr != NULL);
if ((null_bits & null_mask) && f->maybe_null())
f->set_null();
else
{
f->set_notnull();
/*
We only unpack the field if it was non-null
*/
pack_ptr= f->unpack(f->ptr, pack_ptr);
}
bitmap_set_bit(rw_set, f->field_index);
null_mask <<= 1;
}
}
/*
We should now have read all the null bytes, otherwise something is
really wrong.
*/
DBUG_ASSERT(null_ptr == row_data + master_null_byte_count);
*row_end = pack_ptr;
if (master_reclength)
{
if (*field_ptr)
*master_reclength = (*field_ptr)->ptr - (char*) table->record[0];
else
*master_reclength = table->s->reclength;
}
/*
Set properties for remaining columns, if there are any. We let the
corresponding bit in the write_set be set, to write the value if
it was not there already. We iterate over all remaining columns,
even if there were an error, to get as many error messages as
possible. We are still able to return a pointer to the next row,
so redo that.
This generation of error messages is only relevant when inserting
new rows.
*/
for ( ; *field_ptr ; ++field_ptr)
{
uint32 const mask= NOT_NULL_FLAG | NO_DEFAULT_VALUE_FLAG;
Field *const f= *field_ptr;
if (event_type == WRITE_ROWS_EVENT &&
((*field_ptr)->flags & mask) == mask)
{
slave_print_msg(ERROR_LEVEL, rli, ER_NO_DEFAULT_FOR_FIELD,
"Field `%s` of table `%s`.`%s` "
"has no default value and cannot be NULL",
(*field_ptr)->field_name, table->s->db.str,
table->s->table_name.str);
error = ER_NO_DEFAULT_FOR_FIELD;
}
else
f->set_default();
}
DBUG_RETURN(error);
}
#endif // HAVE_REPLICATION
sql/rpl_record.h 0 → 100644
View file @ 0d3f926a
/* Copyright 2007 MySQL AB. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifndef RPL_RECORD_H
#define RPL_RECORD_H
#if !defined(MYSQL_CLIENT)
my_size_t pack_row(TABLE* table, MY_BITMAP const* cols,
byte *row_data, const byte *data);
#endif
#if !defined(MYSQL_CLIENT) && defined(HAVE_REPLICATION)
int unpack_row(RELAY_LOG_INFO const *rli,
TABLE *table, uint const colcnt,
char const *const row_data, MY_BITMAP const *cols,
char const **const row_end, ulong *const master_reclength,
MY_BITMAP* const rw_set,
Log_event_type const event_type);
#endif
#endif
sql/rpl_record_old.cc
View file @ 0d3f926a
......@@ -3,7 +3,7 @@
#include "rpl_record_old.h"
my_size_t
pack_row_old(THD *thd, TABLE *table, MY_BITMAP const* cols,
pack_row_old(TABLE *table, MY_BITMAP const* cols,
byte *row_data, const byte *record)
{
Field **p_field= table->field, *field;
......
sql/rpl_record_old.h
View file @ 0d3f926a
/* Copyright 2007 MySQL AB. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifndef RPL_RECORD_OLD_H
#define RPL_RECORD_OLD_H
#ifndef MYSQL_CLIENT
my_size_t pack_row_old(THD *thd, TABLE *table, MY_BITMAP const* cols,
my_size_t pack_row_old(TABLE *table, MY_BITMAP const* cols,
byte *row_data, const byte *record);
#ifdef HAVE_REPLICATION
......
sql/sql_class.cc
View file @ 0d3f926a
......@@ -27,6 +27,7 @@
#include "mysql_priv.h"
#include "rpl_rli.h"
#include "rpl_record.h"
#include <my_bitmap.h>
#include "log_event.h"
#include <m_ctype.h>
......@@ -2554,112 +2555,6 @@ my_size_t THD::max_row_length_blob(TABLE *table, const byte *data) const
}
/*
Pack a record of data for a table into a format suitable for
transfer via the binary log.
SYNOPSIS
THD::pack_row()
table Table describing the format of the record
cols Bitmap with a set bit for each column that should be
stored in the row
row_data Pointer to memory where row will be written
record Pointer to record that should be packed. It is assumed
that the pointer refers to either record[0] or
record[1], but no such check is made since the code does
not rely on that.
DESCRIPTION
The format for a row in transfer with N fields is the following:
ceil(N/8) null bytes:
One null bit for every column *regardless of whether it can be
null or not*. This simplifies the decoding. Observe that the
number of null bits is equal to the number of set bits in the
'cols' bitmap. The number of null bytes is the smallest number
of bytes necessary to store the null bits.
Padding bits are 1.
N packets:
Each field is stored in packed format.
RETURN VALUE
The number of bytes written at 'row_data'.
*/
my_size_t
THD::pack_row(TABLE *table, MY_BITMAP const* cols,
byte *const row_data, const byte *record) const
{
Field **p_field= table->field, *field;
int const null_byte_count= (bitmap_bits_set(cols) + 7) / 8;
byte *pack_ptr = row_data + null_byte_count;
byte *null_ptr = row_data;
my_ptrdiff_t const rec_offset= record - table->record[0];
my_ptrdiff_t const def_offset= table->s->default_values - table->record[0];
/*
We write the null bits and the packed records using one pass
through all the fields. The null bytes are written little-endian,
i.e., the first fields are in the first byte.
*/
unsigned int null_bits= (1U << 8) - 1;
// Mask to mask out the correct but among the null bits
unsigned int null_mask= 1U;
for ( ; (field= *p_field) ; p_field++)
{
DBUG_PRINT("debug", ("null_mask=%d; null_ptr=%p; row_data=%p; null_byte_count=%d",
null_mask, null_ptr, row_data, null_byte_count));
if (bitmap_is_set(cols, p_field - table->field))
{
my_ptrdiff_t offset;
if (field->is_null(rec_offset))
{
offset= def_offset;
null_bits |= null_mask;
}
else
{
offset= rec_offset;
null_bits &= ~null_mask;
/*
We only store the data of the field if it is non-null
*/
pack_ptr= (byte*)field->pack((char *) pack_ptr, field->ptr + offset);
}
null_mask <<= 1;
if ((null_mask & 0xFF) == 0)
{
DBUG_ASSERT(null_ptr < row_data + null_byte_count);
null_mask = 1U;
*null_ptr++ = null_bits;
null_bits= (1U << 8) - 1;
}
}
}
/*
Write the last (partial) byte, if there is one
*/
if ((null_mask & 0xFF) > 1)
{
DBUG_ASSERT(null_ptr < row_data + null_byte_count);
*null_ptr++ = null_bits;
}
/*
The null pointer should now point to the first byte of the
packed data. If it doesn't, something is very wrong.
*/
DBUG_ASSERT(null_ptr == row_data + null_byte_count);
return static_cast<my_size_t>(pack_ptr - row_data);
}
namespace {
......
sql/sql_class.h
View file @ 0d3f926a
......@@ -1043,9 +1043,6 @@ public:
return (length+max_row_length_blob(table,data));
}
my_size_t pack_row(TABLE* table, MY_BITMAP const* cols, byte *row_data,
const byte *data) const;
int binlog_flush_pending_rows_event(bool stmt_end);
void binlog_delete_pending_rows_event();
......
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