1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
/*
Copyright (c) 2019, 2020 MariaDB
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 Street, Fifth Floor, Boston, MA 02111-1301 USA */
#include "mariadb.h"
#include "sql_class.h"
#include "sql_type_string.h"
uchar *
StringPack::pack(uchar *to, const uchar *from, uint max_length) const
{
size_t length= MY_MIN(m_octet_length, max_length);
size_t local_char_length= char_length();
DBUG_PRINT("debug", ("length: %zu ", length));
if (length > local_char_length)
local_char_length= charset()->charpos(from, from + length,
local_char_length);
set_if_smaller(length, local_char_length);
/*
TODO: change charset interface to add a new function that does
the following or add a flag to lengthsp to do it itself
(this is for not packing padding adding bytes in BINARY
fields).
*/
if (mbmaxlen() == 1)
{
while (length && from[length-1] == charset()->pad_char)
length --;
}
else
length= charset()->lengthsp((const char*) from, length);
// Length always stored little-endian
*to++= (uchar) length;
if (m_octet_length > 255)
*to++= (uchar) (length >> 8);
// Store the actual bytes of the string
memcpy(to, from, length);
return to+length;
}
const uchar *
StringPack::unpack(uchar *to, const uchar *from, const uchar *from_end,
uint param_data) const
{
uint from_length, length;
/*
Compute the declared length of the field on the master. This is
used to decide if one or two bytes should be read as length.
*/
if (param_data)
from_length= (((param_data >> 4) & 0x300) ^ 0x300) + (param_data & 0x00ff);
else
from_length= m_octet_length;
DBUG_PRINT("debug",
("param_data: 0x%x, field_length: %u, from_length: %u",
param_data, m_octet_length, from_length));
/*
Compute the actual length of the data by reading one or two bits
(depending on the declared field length on the master).
*/
if (from_length > 255)
{
if (from + 2 > from_end)
return 0;
length= uint2korr(from);
from+= 2;
}
else
{
if (from + 1 > from_end)
return 0;
length= (uint) *from++;
}
if (from + length > from_end || length > m_octet_length)
return 0;
memcpy(to, from, length);
// Pad the string with the pad character of the fields charset
charset()->fill((char*) to + length,
m_octet_length - length,
charset()->pad_char);
return from+length;
}
|
