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/* - mode: c++ c-basic-offset: 2; indent-tabs-mode: nil; -*-
* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
*
* Copyright (C) 2008 MySQL
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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
*/
#include <config.h>
#include <drizzled/field/varstring.h>
#include <drizzled/table.h>
#include <drizzled/session.h>
#include <plugin/myisam/myisam.h>
#include <string>
using namespace std;
namespace drizzled
{
/****************************************************************************
VARCHAR type
Data in field->ptr is stored as:
1 or 2 bytes length-prefix-header (from Field_varstring::length_bytes)
data
NOTE:
When VARCHAR is stored in a key (for handler::index_read() etc) it's always
stored with a 2 byte prefix. (Just like blob keys).
Normally length_bytes is calculated as (field_length < 256 : 1 ? 2)
The exception is if there is a prefix key field that is part of a long
VARCHAR, in which case field_length for this may be 1 but the length_bytes
is 2.
****************************************************************************/
const uint32_t Field_varstring::MAX_SIZE= UINT16_MAX;
Field_varstring::Field_varstring(unsigned char *ptr_arg,
uint32_t len_arg,
uint32_t length_bytes_arg,
unsigned char *null_ptr_arg,
unsigned char null_bit_arg,
const char *field_name_arg,
const CHARSET_INFO * const cs) :
Field_str(ptr_arg,
len_arg,
null_ptr_arg,
null_bit_arg,
field_name_arg, cs),
length_bytes(length_bytes_arg)
{
}
Field_varstring::Field_varstring(uint32_t len_arg,
bool maybe_null_arg,
const char *field_name_arg,
const CHARSET_INFO * const cs) :
Field_str((unsigned char*) 0,
len_arg,
maybe_null_arg ? (unsigned char*) "": 0,
0,
field_name_arg,
cs),
length_bytes(len_arg < 256 ? 1 :2)
{
}
int Field_varstring::store(const char *from,uint32_t length, const CHARSET_INFO * const cs)
{
uint32_t copy_length;
const char *well_formed_error_pos;
const char *cannot_convert_error_pos;
const char *from_end_pos;
ASSERT_COLUMN_MARKED_FOR_WRITE;
copy_length= well_formed_copy_nchars(field_charset,
(char*) ptr + length_bytes,
field_length,
cs, from, length,
field_length / field_charset->mbmaxlen,
&well_formed_error_pos,
&cannot_convert_error_pos,
&from_end_pos);
if (length_bytes == 1)
*ptr= (unsigned char) copy_length;
else
int2store(ptr, copy_length);
if (check_string_copy_error(this, well_formed_error_pos,
cannot_convert_error_pos, from + length, cs))
return 2;
return report_if_important_data(from_end_pos, from + length);
}
int Field_varstring::store(int64_t nr, bool unsigned_val)
{
char buff[64];
uint32_t length;
length= (uint32_t) (field_charset->cset->int64_t10_to_str)(field_charset,
buff,
sizeof(buff),
(unsigned_val ? 10: -10),
nr);
return Field_varstring::store(buff, length, field_charset);
}
double Field_varstring::val_real(void) const
{
int not_used;
char *end_not_used;
ASSERT_COLUMN_MARKED_FOR_READ;
uint32_t length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
return my_strntod(field_charset, (char*) ptr+length_bytes, length,
&end_not_used, ¬_used);
}
int64_t Field_varstring::val_int(void) const
{
int not_used;
char *end_not_used;
uint32_t length;
ASSERT_COLUMN_MARKED_FOR_READ;
length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
return my_strntoll(field_charset, (char*) ptr+length_bytes, length, 10,
&end_not_used, ¬_used);
}
String *Field_varstring::val_str(String *, String *val_ptr) const
{
uint32_t length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
ASSERT_COLUMN_MARKED_FOR_READ;
val_ptr->set((const char*) ptr+length_bytes, length, field_charset);
return val_ptr;
}
type::Decimal *Field_varstring::val_decimal(type::Decimal *decimal_value) const
{
uint32_t length;
ASSERT_COLUMN_MARKED_FOR_READ;
length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
decimal_value->store(E_DEC_FATAL_ERROR, (char*) ptr+length_bytes, length, charset());
return decimal_value;
}
int Field_varstring::cmp_max(const unsigned char *a_ptr, const unsigned char *b_ptr,
uint32_t max_len)
{
uint32_t a_length, b_length;
int diff;
if (length_bytes == 1)
{
a_length= (uint32_t) *a_ptr;
b_length= (uint32_t) *b_ptr;
}
else
{
a_length= uint2korr(a_ptr);
b_length= uint2korr(b_ptr);
}
set_if_smaller(a_length, max_len);
set_if_smaller(b_length, max_len);
diff= field_charset->coll->strnncollsp(field_charset,
a_ptr+
length_bytes,
a_length,
b_ptr+
length_bytes,
b_length,0);
return diff;
}
/**
@note
varstring and blob keys are ALWAYS stored with a 2 byte length prefix
*/
int Field_varstring::key_cmp(const unsigned char *key_ptr, uint32_t max_key_length)
{
uint32_t length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
uint32_t local_char_length= max_key_length / field_charset->mbmaxlen;
local_char_length= my_charpos(field_charset, ptr + length_bytes,
ptr + length_bytes + length, local_char_length);
set_if_smaller(length, local_char_length);
return field_charset->coll->strnncollsp(field_charset,
ptr + length_bytes,
length,
key_ptr+
HA_KEY_BLOB_LENGTH,
uint2korr(key_ptr), 0);
}
/**
Compare to key segments (always 2 byte length prefix).
@note
This is used only to compare key segments created for index_read().
(keys are created and compared in key.cc)
*/
int Field_varstring::key_cmp(const unsigned char *a,const unsigned char *b)
{
return field_charset->coll->strnncollsp(field_charset,
a + HA_KEY_BLOB_LENGTH,
uint2korr(a),
b + HA_KEY_BLOB_LENGTH,
uint2korr(b),
0);
}
void Field_varstring::sort_string(unsigned char *to,uint32_t length)
{
uint32_t tot_length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
if (field_charset == &my_charset_bin)
{
/* Store length last in high-byte order to sort longer strings first */
if (length_bytes == 1)
to[length-1]= tot_length;
else
mi_int2store(to+length-2, tot_length);
length-= length_bytes;
}
tot_length= my_strnxfrm(field_charset,
to, length, ptr + length_bytes,
tot_length);
assert(tot_length == length);
}
enum ha_base_keytype Field_varstring::key_type() const
{
enum ha_base_keytype res;
if (binary())
res= length_bytes == 1 ? HA_KEYTYPE_VARBINARY1 : HA_KEYTYPE_VARBINARY2;
else
res= length_bytes == 1 ? HA_KEYTYPE_VARTEXT1 : HA_KEYTYPE_VARTEXT2;
return res;
}
void Field_varstring::sql_type(String &res) const
{
const CHARSET_INFO * const cs=res.charset();
uint32_t length;
length= cs->cset->snprintf(cs,(char*) res.ptr(),
res.alloced_length(), "%s(%d)",
(has_charset() ? "varchar" : "varbinary"),
(int) field_length / charset()->mbmaxlen);
res.length(length);
}
uint32_t Field_varstring::used_length()
{
return length_bytes == 1 ? 1 + (uint32_t) (unsigned char) *ptr : 2 + uint2korr(ptr);
}
/*
Functions to create a packed row.
Here the number of length bytes are depending on the given max_length
*/
unsigned char *Field_varstring::pack(unsigned char *to, const unsigned char *from,
uint32_t max_length,
bool )
{
uint32_t length= length_bytes == 1 ? (uint32_t) *from : uint2korr(from);
set_if_smaller(max_length, field_length);
if (length > max_length)
length=max_length;
/* Length always stored little-endian */
*to++= length & 0xFF;
if (max_length > 255)
*to++= (length >> 8) & 0xFF;
/* Store bytes of string */
if (length > 0)
memcpy(to, from+length_bytes, length);
return to+length;
}
/**
Unpack a varstring field from row data.
This method is used to unpack a varstring field from a master
whose size of the field is less than that of the slave.
@note
The string length is always packed little-endian.
@param to Destination of the data
@param from Source of the data
@param param_data Length bytes from the master's field data
@return New pointer into memory based on from + length of the data
*/
const unsigned char *
Field_varstring::unpack(unsigned char *to, const unsigned char *from,
uint32_t param_data,
bool )
{
uint32_t length;
uint32_t l_bytes= (param_data && (param_data < field_length)) ?
(param_data <= 255) ? 1 : 2 : length_bytes;
if (l_bytes == 1)
{
to[0]= *from++;
length= to[0];
if (length_bytes == 2)
to[1]= 0;
}
else /* l_bytes == 2 */
{
length= uint2korr(from);
to[0]= *from++;
to[1]= *from++;
}
if (length)
memcpy(to+ length_bytes, from, length);
return from+length;
}
uint32_t Field_varstring::max_packed_col_length(uint32_t max_length)
{
return (max_length > 255 ? 2 : 1)+max_length;
}
uint32_t Field_varstring::get_key_image(basic_string<unsigned char> &buff, uint32_t length)
{
/* Key is always stored with 2 bytes */
const uint32_t key_len= 2;
uint32_t f_length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
uint32_t local_char_length= length / field_charset->mbmaxlen;
unsigned char *pos= ptr+length_bytes;
local_char_length= my_charpos(field_charset, pos, pos + f_length,
local_char_length);
set_if_smaller(f_length, local_char_length);
unsigned char len_buff[key_len];
int2store(len_buff,f_length);
buff.append(len_buff);
buff.append(pos, f_length);
if (f_length < length)
{
/*
Must clear this as we do a memcmp in optimizer/range.cc to detect
identical keys
*/
buff.append(length-f_length, 0);
}
return key_len+f_length;
}
uint32_t Field_varstring::get_key_image(unsigned char *buff, uint32_t length)
{
uint32_t f_length= length_bytes == 1 ? (uint32_t) *ptr : uint2korr(ptr);
uint32_t local_char_length= length / field_charset->mbmaxlen;
unsigned char *pos= ptr+length_bytes;
local_char_length= my_charpos(field_charset, pos, pos + f_length,
local_char_length);
set_if_smaller(f_length, local_char_length);
/* Key is always stored with 2 bytes */
int2store(buff,f_length);
memcpy(buff+HA_KEY_BLOB_LENGTH, pos, f_length);
if (f_length < length)
{
/*
Must clear this as we do a memcmp in optimizer/range.cc to detect
identical keys
*/
memset(buff+HA_KEY_BLOB_LENGTH+f_length, 0, (length-f_length));
}
return HA_KEY_BLOB_LENGTH+f_length;
}
void Field_varstring::set_key_image(const unsigned char *buff, uint32_t length)
{
length= uint2korr(buff); // Real length is here
(void) Field_varstring::store((const char*) buff+HA_KEY_BLOB_LENGTH, length, field_charset);
}
int Field_varstring::cmp_binary(const unsigned char *a_ptr,
const unsigned char *b_ptr,
uint32_t max_length)
{
uint32_t a_length,b_length;
if (length_bytes == 1)
{
a_length= (uint32_t) *a_ptr;
b_length= (uint32_t) *b_ptr;
}
else
{
a_length= uint2korr(a_ptr);
b_length= uint2korr(b_ptr);
}
set_if_smaller(a_length, max_length);
set_if_smaller(b_length, max_length);
if (a_length != b_length)
return 1;
return memcmp(a_ptr+length_bytes, b_ptr+length_bytes, a_length);
}
Field *Field_varstring::new_field(memory::Root *root, Table *new_table, bool keep_type)
{
Field_varstring *res= (Field_varstring*) Field::new_field(root, new_table,
keep_type);
if (res)
res->length_bytes= length_bytes;
return res;
}
Field *Field_varstring::new_key_field(memory::Root *root,
Table *new_table,
unsigned char *new_ptr, unsigned char *new_null_ptr,
uint32_t new_null_bit)
{
Field_varstring *res;
if ((res= (Field_varstring*) Field::new_key_field(root,
new_table,
new_ptr,
new_null_ptr,
new_null_bit)))
{
/* Keys length prefixes are always packed with 2 bytes */
res->length_bytes= 2;
}
return res;
}
} /* namespace drizzled */
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