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
|
/* Copyright (C) 2003 MySQL AB
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
#ifndef __BUFFER_HPP_INCLUDED__
#define __BUFFER_HPP_INCLUDED__
#include <ndb_global.h>
/* This class represents a buffer of binary data, where you can append
* data at the end, and later read the entire bunch.
* It will take care of the hairy details of realloc()ing the space
* for you
*/
class UtilBuffer {
public:
UtilBuffer() { data = NULL; len = 0; alloc_size = 0; };
~UtilBuffer() { if(data) free(data); data = NULL; len = 0; alloc_size = 0; };
int reallocate(size_t newsize) {
if(newsize < len) {
errno = EINVAL;
return -1;
}
void *newdata;
if((newdata = realloc(data, newsize)) == NULL) {
errno = ENOMEM;
return -1;
}
alloc_size = newsize;
data = newdata;
return 0;
};
int grow(size_t l) {
if(l > alloc_size)
return reallocate(l);
return 0;
};
int append(const void *d, size_t l) {
int ret;
ret = grow(len+l);
if(ret != 0)
return ret;
memcpy((char *)data+len, d, l);
len+=l;
return 0;
};
void * append(size_t l){
if(grow(len+l) != 0)
return 0;
void * ret = (char*)data+len;
len += l;
return ret;
}
int assign(const void * d, size_t l) {
if (data) free(data);
data = NULL;
len = 0;
alloc_size = 0;
return append(d, l);
}
void clear() {
len = 0;
}
int length() const { return len; };
void *get_data() const { return data; };
private:
void *data; /* Pointer to data storage */
size_t len; /* Size of the stored data */
size_t alloc_size; /* Size of the allocated space,
* i.e. len can grow to this size */
};
#endif /* !__BUFFER_HPP_INCLUDED__ */
|
