mysql/sql/field_conv.cc at t6-dev · sateeshgithub/mysql · GitHub

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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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */

/**

@file

@brief

Functions to copy data to or from fields

This could be done with a single short function but opencoding this

gives much more speed.

#include "sql_priv.h"

#include "sql_class.h" // THD

#include <m_ctype.h>

static void do_field_eq(Copy_field *copy)

{

memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);

}

static void do_field_1(Copy_field *copy)

{

copy->to_ptr[0]=copy->from_ptr[0];

}

static void do_field_2(Copy_field *copy)

{

copy->to_ptr[0]=copy->from_ptr[0];

copy->to_ptr[1]=copy->from_ptr[1];

}

static void do_field_3(Copy_field *copy)

{

copy->to_ptr[0]=copy->from_ptr[0];

copy->to_ptr[1]=copy->from_ptr[1];

copy->to_ptr[2]=copy->from_ptr[2];

}

static void do_field_4(Copy_field *copy)

{

copy->to_ptr[0]=copy->from_ptr[0];

copy->to_ptr[1]=copy->from_ptr[1];

copy->to_ptr[2]=copy->from_ptr[2];

copy->to_ptr[3]=copy->from_ptr[3];

}

static void do_field_6(Copy_field *copy)

{ // For blob field

copy->to_ptr[0]=copy->from_ptr[0];

copy->to_ptr[1]=copy->from_ptr[1];

copy->to_ptr[2]=copy->from_ptr[2];

copy->to_ptr[3]=copy->from_ptr[3];

copy->to_ptr[4]=copy->from_ptr[4];

copy->to_ptr[5]=copy->from_ptr[5];

}

static void do_field_8(Copy_field *copy)

{

copy->to_ptr[0]=copy->from_ptr[0];

copy->to_ptr[1]=copy->from_ptr[1];

copy->to_ptr[2]=copy->from_ptr[2];

copy->to_ptr[3]=copy->from_ptr[3];

copy->to_ptr[4]=copy->from_ptr[4];

copy->to_ptr[5]=copy->from_ptr[5];

copy->to_ptr[6]=copy->from_ptr[6];

copy->to_ptr[7]=copy->from_ptr[7];

}

static void do_field_to_null_str(Copy_field *copy)

{

if (*copy->from_null_ptr & copy->from_bit)

{

bzero(copy->to_ptr,copy->from_length);

copy->to_null_ptr[0]=1; // Always bit 1

}

else

{

copy->to_null_ptr[0]=0;

memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);

}

static void do_outer_field_to_null_str(Copy_field *copy)

{

if (*copy->null_row ||

(copy->from_null_ptr && (*copy->from_null_ptr & copy->from_bit)))

{

bzero(copy->to_ptr,copy->from_length);

copy->to_null_ptr[0]=1; // Always bit 1

}

else

{

copy->to_null_ptr[0]=0;

memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);

}

int

set_field_to_null(Field *field)

{

if (field->real_maybe_null())

{

field->set_null();

field->reset();

return 0;

}

field->reset();

switch (field->table->in_use->count_cuted_fields) {

case CHECK_FIELD_WARN:

field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN, WARN_DATA_TRUNCATED, 1);

/* fall through */

case CHECK_FIELD_IGNORE:

return 0;

case CHECK_FIELD_ERROR_FOR_NULL:

if (!field->table->in_use->no_errors)

my_error(ER_BAD_NULL_ERROR, MYF(0), field->field_name);

return -1;

}

DBUG_ASSERT(0); // impossible

return -1;

}

/**

Set field to NULL or TIMESTAMP or to next auto_increment number.

@param field Field to update

@param no_conversions Set to 1 if we should return 1 if field can't

take null values.

If set to 0 we will do store the 'default value'

if the field is a special field. If not we will

give an error.

@retval

0 Field could take 0 or an automatic conversion was used

@retval

-1 Field could not take NULL and no conversion was used.

If no_conversion was not set, an error message is printed

int

set_field_to_null_with_conversions(Field *field, bool no_conversions)

{

if (field->real_maybe_null())

{

field->set_null();

field->reset();

return 0;

}

if (no_conversions)

return -1;

Check if this is a special type, which will get a special walue

when set to NULL (TIMESTAMP fields which allow setting to NULL

are handled by first check).

if (field->type() == MYSQL_TYPE_TIMESTAMP)

{

((Field_timestamp*) field)->set_time();

return 0; // Ok to set time to NULL

}

// Note: we ignore any potential failure of reset() here.

field->reset();

if (field == field->table->next_number_field)

{

field->table->auto_increment_field_not_null= FALSE;

return 0; // field is set in fill_record()

}

switch (field->table->in_use->count_cuted_fields) {

case CHECK_FIELD_WARN:

field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN, ER_BAD_NULL_ERROR, 1);

/* fall through */

case CHECK_FIELD_IGNORE:

return 0;

case CHECK_FIELD_ERROR_FOR_NULL:

if (!field->table->in_use->no_errors)

my_error(ER_BAD_NULL_ERROR, MYF(0), field->field_name);

return -1;

}

DBUG_ASSERT(0); // impossible

return -1;

}

static void do_skip(Copy_field *copy __attribute__((unused)))

{

}

static void do_copy_null(Copy_field *copy)

{

if (*copy->from_null_ptr & copy->from_bit)

{

*copy->to_null_ptr|=copy->to_bit;

copy->to_field->reset();

}

else

{

*copy->to_null_ptr&= ~copy->to_bit;

(copy->do_copy2)(copy);

}

static void do_outer_field_null(Copy_field *copy)

{

if (*copy->null_row ||

(copy->from_null_ptr && (*copy->from_null_ptr & copy->from_bit)))

{

*copy->to_null_ptr|=copy->to_bit;

copy->to_field->reset();

}

else

{

*copy->to_null_ptr&= ~copy->to_bit;

(copy->do_copy2)(copy);

}

static void do_copy_not_null(Copy_field *copy)

{

if (*copy->from_null_ptr & copy->from_bit)

{

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

copy->to_field->reset();

}

else

(copy->do_copy2)(copy);

}

static void do_copy_maybe_null(Copy_field *copy)

{

*copy->to_null_ptr&= ~copy->to_bit;

(copy->do_copy2)(copy);

}

/* timestamp and next_number has special handling in case of NULL values */

static void do_copy_timestamp(Copy_field *copy)

{

if (*copy->from_null_ptr & copy->from_bit)

{

/* Same as in set_field_to_null_with_conversions() */

((Field_timestamp*) copy->to_field)->set_time();

}

else

(copy->do_copy2)(copy);

}

static void do_copy_next_number(Copy_field *copy)

{

if (*copy->from_null_ptr & copy->from_bit)

{

/* Same as in set_field_to_null_with_conversions() */

copy->to_field->table->auto_increment_field_not_null= FALSE;

copy->to_field->reset();

}

else

(copy->do_copy2)(copy);

}

static void do_copy_blob(Copy_field *copy)

{

ulong length=((Field_blob*) copy->from_field)->get_length();

((Field_blob*) copy->to_field)->store_length(length);

memcpy(copy->to_ptr, copy->from_ptr, sizeof(char*));

}

static void do_conv_blob(Copy_field *copy)

{

copy->from_field->val_str(&copy->tmp);

((Field_blob *) copy->to_field)->store(copy->tmp.ptr(),

copy->tmp.length(),

copy->tmp.charset());

}

/** Save blob in copy->tmp for GROUP BY. */

static void do_save_blob(Copy_field *copy)

{

char buff[MAX_FIELD_WIDTH];

String res(buff,sizeof(buff),copy->tmp.charset());

copy->from_field->val_str(&res);

copy->tmp.copy(res);

((Field_blob *) copy->to_field)->store(copy->tmp.ptr(),

copy->tmp.length(),

copy->tmp.charset());

}

static void do_field_string(Copy_field *copy)

{

char buff[MAX_FIELD_WIDTH];

copy->tmp.set_quick(buff,sizeof(buff),copy->tmp.charset());

copy->from_field->val_str(&copy->tmp);

copy->to_field->store(copy->tmp.c_ptr_quick(),copy->tmp.length(),

copy->tmp.charset());

}

static void do_field_enum(Copy_field *copy)

{

if (copy->from_field->val_int() == 0)

((Field_enum *) copy->to_field)->store_type((ulonglong) 0);

else

do_field_string(copy);

}

static void do_field_varbinary_pre50(Copy_field *copy)

{

char buff[MAX_FIELD_WIDTH];

copy->tmp.set_quick(buff,sizeof(buff),copy->tmp.charset());

copy->from_field->val_str(&copy->tmp);

/* Use the same function as in 4.1 to trim trailing spaces */

uint length= my_lengthsp_8bit(&my_charset_bin, copy->tmp.c_ptr_quick(),

copy->from_field->field_length);

copy->to_field->store(copy->tmp.c_ptr_quick(), length,

copy->tmp.charset());

}

static void do_field_int(Copy_field *copy)

{

longlong value= copy->from_field->val_int();

copy->to_field->store(value,

test(copy->from_field->flags & UNSIGNED_FLAG));

}

static void do_field_real(Copy_field *copy)

{

double value=copy->from_field->val_real();

copy->to_field->store(value);

}

static void do_field_decimal(Copy_field *copy)

{

my_decimal value;

copy->to_field->store_decimal(copy->from_field->val_decimal(&value));

}

/**

string copy for single byte characters set when to string is shorter than

from string.

static void do_cut_string(Copy_field *copy)

{

CHARSET_INFO *cs= copy->from_field->charset();

memcpy(copy->to_ptr,copy->from_ptr,copy->to_length);

/* Check if we loosed any important characters */

if (cs->cset->scan(cs,

(char*) copy->from_ptr + copy->to_length,

(char*) copy->from_ptr + copy->from_length,

MY_SEQ_SPACES) < copy->from_length - copy->to_length)

{

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

}

/**

string copy for multi byte characters set when to string is shorter than

from string.

static void do_cut_string_complex(Copy_field *copy)

{ // Shorter string field

int well_formed_error;

CHARSET_INFO *cs= copy->from_field->charset();

const uchar *from_end= copy->from_ptr + copy->from_length;

uint copy_length= cs->cset->well_formed_len(cs,

(char*) copy->from_ptr,

(char*) from_end,

copy->to_length / cs->mbmaxlen,

&well_formed_error);

if (copy->to_length < copy_length)

copy_length= copy->to_length;

memcpy(copy->to_ptr, copy->from_ptr, copy_length);

/* Check if we lost any important characters */

if (well_formed_error ||

cs->cset->scan(cs, (char*) copy->from_ptr + copy_length,

(char*) from_end,

MY_SEQ_SPACES) < (copy->from_length - copy_length))

{

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

}

if (copy_length < copy->to_length)

cs->cset->fill(cs, (char*) copy->to_ptr + copy_length,

copy->to_length - copy_length, ' ');

}

static void do_expand_binary(Copy_field *copy)

{

CHARSET_INFO *cs= copy->from_field->charset();

memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);

cs->cset->fill(cs, (char*) copy->to_ptr+copy->from_length,

copy->to_length-copy->from_length, '\0');

}

static void do_expand_string(Copy_field *copy)

{

CHARSET_INFO *cs= copy->from_field->charset();

memcpy(copy->to_ptr,copy->from_ptr,copy->from_length);

cs->cset->fill(cs, (char*) copy->to_ptr+copy->from_length,

copy->to_length-copy->from_length, ' ');

}

static void do_varstring1(Copy_field *copy)

{

uint length= (uint) *(uchar*) copy->from_ptr;

if (length > copy->to_length- 1)

{

length=copy->to_length - 1;

if (copy->from_field->table->in_use->count_cuted_fields)

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

}

*(uchar*) copy->to_ptr= (uchar) length;

memcpy(copy->to_ptr+1, copy->from_ptr + 1, length);

}

static void do_varstring1_mb(Copy_field *copy)

{

int well_formed_error;

CHARSET_INFO *cs= copy->from_field->charset();

uint from_length= (uint) *(uchar*) copy->from_ptr;

const uchar *from_ptr= copy->from_ptr + 1;

uint to_char_length= (copy->to_length - 1) / cs->mbmaxlen;

uint length= cs->cset->well_formed_len(cs, (char*) from_ptr,

(char*) from_ptr + from_length,

to_char_length, &well_formed_error);

if (length < from_length)

{

if (current_thd->count_cuted_fields)

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

}

*copy->to_ptr= (uchar) length;

memcpy(copy->to_ptr + 1, from_ptr, length);

}

static void do_varstring2(Copy_field *copy)

{

uint length=uint2korr(copy->from_ptr);

if (length > copy->to_length- HA_KEY_BLOB_LENGTH)

{

length=copy->to_length-HA_KEY_BLOB_LENGTH;

if (copy->from_field->table->in_use->count_cuted_fields)

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

}

int2store(copy->to_ptr,length);

memcpy(copy->to_ptr+HA_KEY_BLOB_LENGTH, copy->from_ptr + HA_KEY_BLOB_LENGTH,

length);

}

static void do_varstring2_mb(Copy_field *copy)

{

int well_formed_error;

CHARSET_INFO *cs= copy->from_field->charset();

uint char_length= (copy->to_length - HA_KEY_BLOB_LENGTH) / cs->mbmaxlen;

uint from_length= uint2korr(copy->from_ptr);

const uchar *from_beg= copy->from_ptr + HA_KEY_BLOB_LENGTH;

uint length= cs->cset->well_formed_len(cs, (char*) from_beg,

(char*) from_beg + from_length,

char_length, &well_formed_error);

if (length < from_length)

{

if (current_thd->count_cuted_fields)

copy->to_field->set_warning(MYSQL_ERROR::WARN_LEVEL_WARN,

WARN_DATA_TRUNCATED, 1);

}

int2store(copy->to_ptr, length);

memcpy(copy->to_ptr+HA_KEY_BLOB_LENGTH, from_beg, length);

}

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

** The different functions that fills in a Copy_field class

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

/**

copy of field to maybe null string.

If field is null then the all bytes are set to 0.

if field is not null then the first byte is set to 1 and the rest of the

string is the field value.

The 'to' buffer should have a size of field->pack_length()+1

void Copy_field::set(uchar *to,Field *from)

{

from_ptr=from->ptr;

to_ptr=to;

from_length=from->pack_length();

if (from->maybe_null())

{

from_null_ptr=from->null_ptr;

from_bit= from->null_bit;

to_ptr[0]= 1; // Null as default value

to_null_ptr= (uchar*) to_ptr++;

to_bit= 1;

if (from->table->maybe_null)

{

null_row= &from->table->null_row;

do_copy= do_outer_field_to_null_str;

}

else

do_copy= do_field_to_null_str;

}

else

{

to_null_ptr= 0; // For easy debugging

do_copy= do_field_eq;

}

To do:

If 'save\ is set to true and the 'from' is a blob field, do_copy is set to

do_save_blob rather than do_conv_blob. The only differences between them

appears to be:

- do_save_blob allocates and uses an intermediate buffer before calling

Field_blob::store. Is this in order to trigger the call to

well_formed_copy_nchars, by changing the pointer copy->tmp.ptr()?

That call will take place anyway in all known cases.

- The above causes a truncation to MAX_FIELD_WIDTH. Is this the intended

effect? Truncation is handled by well_formed_copy_nchars anyway.

void Copy_field::set(Field *to,Field *from,bool save)

{

if (to->type() == MYSQL_TYPE_NULL)

{

to_null_ptr=0; // For easy debugging

to_ptr=0;

do_copy=do_skip;

return;

}

from_field=from;

to_field=to;

from_ptr=from->ptr;

from_length=from->pack_length();

to_ptr= to->ptr;

to_length=to_field->pack_length();

// set up null handling

from_null_ptr=to_null_ptr=0;

if (from->maybe_null())

{

from_null_ptr= from->null_ptr;

from_bit= from->null_bit;

if (to_field->real_maybe_null())

{

to_null_ptr= to->null_ptr;

to_bit= to->null_bit;

if (from_null_ptr)

do_copy= do_copy_null;

else

{

null_row= &from->table->null_row;

do_copy= do_outer_field_null;

}

else

{

if (to_field->type() == MYSQL_TYPE_TIMESTAMP)

do_copy= do_copy_timestamp; // Automatic timestamp

else if (to_field == to_field->table->next_number_field)

do_copy= do_copy_next_number;

else

do_copy= do_copy_not_null;

}

else if (to_field->real_maybe_null())

{

to_null_ptr= to->null_ptr;

to_bit= to->null_bit;

do_copy= do_copy_maybe_null;

}

else

do_copy=0;

if ((to->flags & BLOB_FLAG) && save)

do_copy2= do_save_blob;

else

do_copy2= get_copy_func(to,from);

if (!do_copy) // Not null

do_copy=do_copy2;

}

Copy_field::Copy_func *

Copy_field::get_copy_func(Field *to,Field *from)

{

bool compatible_db_low_byte_first= (to->table->s->db_low_byte_first ==

from->table->s->db_low_byte_first);

if (to->flags & BLOB_FLAG)

{

if (!(from->flags & BLOB_FLAG) || from->charset() != to->charset())

return do_conv_blob;

if (from_length != to_length || !compatible_db_low_byte_first)

{

// Correct pointer to point at char pointer

to_ptr+= to_length - to->table->s->blob_ptr_size;

from_ptr+= from_length- from->table->s->blob_ptr_size;

return do_copy_blob;

}

else

{

if (to->real_type() == MYSQL_TYPE_BIT ||

from->real_type() == MYSQL_TYPE_BIT)

return do_field_int;

if (to->result_type() == DECIMAL_RESULT)

return do_field_decimal;

// Check if identical fields

if (from->result_type() == STRING_RESULT)

{

Detect copy from pre 5.0 varbinary to varbinary as of 5.0 and

use special copy function that removes trailing spaces and thus

repairs data.

if (from->type() == MYSQL_TYPE_VAR_STRING && !from->has_charset() &&

to->type() == MYSQL_TYPE_VARCHAR && !to->has_charset())

return do_field_varbinary_pre50;

If we are copying date or datetime's we have to check the dates

if we don't allow 'all' dates.

if (to->real_type() != from->real_type() ||

!compatible_db_low_byte_first ||

(((to->table->in_use->variables.sql_mode &

(MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE | MODE_INVALID_DATES)) &&

to->type() == MYSQL_TYPE_DATE) ||

to->type() == MYSQL_TYPE_DATETIME))

{

if (from->real_type() == MYSQL_TYPE_ENUM ||

from->real_type() == MYSQL_TYPE_SET)

if (to->result_type() != STRING_RESULT)

return do_field_int; // Convert SET to number

return do_field_string;

}

if (to->real_type() == MYSQL_TYPE_ENUM ||

to->real_type() == MYSQL_TYPE_SET)

{

if (!to->eq_def(from))

{

if (from->real_type() == MYSQL_TYPE_ENUM &&

to->real_type() == MYSQL_TYPE_ENUM)

return do_field_enum;

else

return do_field_string;

}

else if (to->charset() != from->charset())

return do_field_string;

else if (to->real_type() == MYSQL_TYPE_VARCHAR)

{

if (((Field_varstring*) to)->length_bytes !=

((Field_varstring*) from)->length_bytes)

return do_field_string;

else

return (((Field_varstring*) to)->length_bytes == 1 ?

(from->charset()->mbmaxlen == 1 ? do_varstring1 :

do_varstring1_mb) :

(from->charset()->mbmaxlen == 1 ? do_varstring2 :

do_varstring2_mb));

}

else if (to_length < from_length)

return (from->charset()->mbmaxlen == 1 ?

do_cut_string : do_cut_string_complex);

else if (to_length > from_length)

{

if (to->charset() == &my_charset_bin)

return do_expand_binary;

else

return do_expand_string;

}

else if (to->real_type() != from->real_type() ||

to_length != from_length ||

!compatible_db_low_byte_first)

{

if (to->real_type() == MYSQL_TYPE_DECIMAL ||

to->result_type() == STRING_RESULT)

return do_field_string;

if (to->result_type() == INT_RESULT)

return do_field_int;

return do_field_real;

}

else

{

if (!to->eq_def(from) || !compatible_db_low_byte_first)

{

if (to->real_type() == MYSQL_TYPE_DECIMAL)

return do_field_string;

if (to->result_type() == INT_RESULT)

return do_field_int;

else

return do_field_real;

}

/* Eq fields */

switch (to_length) {

case 1: return do_field_1;

case 2: return do_field_2;

case 3: return do_field_3;

case 4: return do_field_4;

case 6: return do_field_6;

case 8: return do_field_8;

}

return do_field_eq;

}

/** Simple quick field convert that is called on insert. */

int field_conv(Field *to,Field *from)

{

if (to->real_type() == from->real_type() &&

!(to->type() == MYSQL_TYPE_BLOB && to->table->copy_blobs))

{

if (to->pack_length() == from->pack_length() &&

!(to->flags & UNSIGNED_FLAG && !(from->flags & UNSIGNED_FLAG)) &&

to->real_type() != MYSQL_TYPE_ENUM &&

to->real_type() != MYSQL_TYPE_SET &&

to->real_type() != MYSQL_TYPE_BIT &&

(to->real_type() != MYSQL_TYPE_NEWDECIMAL ||

(to->field_length == from->field_length &&

(((Field_num*)to)->dec == ((Field_num*)from)->dec))) &&

from->charset() == to->charset() &&

to->table->s->db_low_byte_first == from->table->s->db_low_byte_first &&

(!(to->table->in_use->variables.sql_mode &

(MODE_NO_ZERO_IN_DATE | MODE_NO_ZERO_DATE | MODE_INVALID_DATES)) ||

(to->type() != MYSQL_TYPE_DATE &&

to->type() != MYSQL_TYPE_DATETIME)) &&

(from->real_type() != MYSQL_TYPE_VARCHAR ||

((Field_varstring*)from)->length_bytes ==

((Field_varstring*)to)->length_bytes))

{ // Identical fields

// to->ptr==from->ptr may happen if one does 'UPDATE ... SET x=x'

memmove(to->ptr, from->ptr, to->pack_length());

return 0;

}

if (to->type() == MYSQL_TYPE_BLOB)

{ // Be sure the value is stored

Field_blob *blob=(Field_blob*) to;

from->val_str(&blob->value);

Copy value if copy_blobs is set, or source is not a string and

we have a pointer to its internal string conversion buffer.

if (to->table->copy_blobs ||

(!blob->value.is_alloced() &&

from->real_type() != MYSQL_TYPE_STRING &&

from->real_type() != MYSQL_TYPE_VARCHAR))

blob->value.copy();

return blob->store(blob->value.ptr(),blob->value.length(),from->charset());

}

if (from->real_type() == MYSQL_TYPE_ENUM &&

to->real_type() == MYSQL_TYPE_ENUM &&

from->val_int() == 0)

{

((Field_enum *)(to))->store_type(0);

return 0;

}

else if ((from->result_type() == STRING_RESULT &&

(to->result_type() == STRING_RESULT ||

(from->real_type() != MYSQL_TYPE_ENUM &&

from->real_type() != MYSQL_TYPE_SET))) ||

to->type() == MYSQL_TYPE_DECIMAL)

{

char buff[MAX_FIELD_WIDTH];

String result(buff,sizeof(buff),from->charset());

from->val_str(&result);

We use c_ptr_quick() here to make it easier if to is a float/double

as the conversion routines will do a copy of the result doesn't

end with \0. Can be replaced with .ptr() when we have our own

string->double conversion.

return to->store(result.c_ptr_quick(),result.length(),from->charset());

}

else if (from->result_type() == REAL_RESULT)

return to->store(from->val_real());

else if (from->result_type() == DECIMAL_RESULT)

{

my_decimal buff;

return to->store_decimal(from->val_decimal(&buff));

}

else

return to->store(from->val_int(), test(from->flags & UNSIGNED_FLAG));

}

mysql/sql/field_conv.cc at t6-dev · sateeshgithub/mysql · GitHub

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