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) 1994 James Clark
// See the file COPYING for copying permission.
#include "splib.h"
#include "Allocator.h"
#include "macros.h"
#ifdef SP_NAMESPACE
namespace SP_NAMESPACE {
#endif
Allocator::Allocator(size_t maxSize, unsigned blocksPerSegment)
: objectSize_(maxSize),
blocksPerSegment_(blocksPerSegment),
freeList_(0),
segments_(0)
{
}
Allocator::~Allocator()
{
SegmentHeader *p = segments_;
while (p) {
SegmentHeader *tem = p->next;
if (p->liveCount == 0)
::operator delete(p);
else
p->freeList = 0;
p = tem;
}
}
void *Allocator::alloc(size_t sz)
{
if (sz > objectSize_)
tooBig(sz);
Block *tem = freeList_;
if (tem) {
tem->header.seg->liveCount += 1;
freeList_ = tem->next;
return &(tem->next);
}
else
return alloc1();
}
void *Allocator::allocSimple(size_t sz)
{
BlockHeader *p = (BlockHeader *)::operator new(sz + sizeof(BlockHeader));
p->seg = 0;
return p + 1;
}
void Allocator::free(void *p)
{
BlockHeader *b = ((BlockHeader *)p) - 1;
SegmentHeader *seg = b->seg;
if (seg == 0)
::operator delete(b);
else {
Block **freeList = seg->freeList;
if (freeList == 0) {
seg->liveCount -= 1;
if (seg->liveCount == 0)
::operator delete(seg);
}
else {
((Block *)b)->next = *freeList;
*freeList = (Block *)b;
seg->liveCount -= 1;
}
}
}
void *Allocator::alloc1()
{
SegmentHeader *seg
= (SegmentHeader *)::operator new(sizeof(SegmentHeader)
+ ((objectSize_ + sizeof(BlockHeader))
* blocksPerSegment_));
seg->next = segments_;
segments_ = seg;
seg->liveCount = 1;
seg->freeList = &freeList_;
char *p = (char *)(seg + 1);
Block *head = 0;
for (size_t n = blocksPerSegment_; n > 0; n--) {
((Block *)p)->next = head;
((Block *)p)->header.seg = seg;
head = (Block *)p;
p += sizeof(BlockHeader) + objectSize_;
}
freeList_ = head->next;
return &(head->next);
}
void Allocator::tooBig(size_t sz)
{
ASSERT(sz <= objectSize_);
}
#ifdef SP_NAMESPACE
}
#endif
|
