blob: c1c09eaf4b34a2cb0e72c0104e861fb9b0b1913a (
plain)
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
|
/* (c) Magnus Auvinen. See licence.txt in the root of the distribution for more information. */
/* If you are missing that file, acquire a complete release at teeworlds.com. */
#include <base/system.h>
#include "memheap.h"
static const int CHUNK_SIZE = 1024*64;
// allocates a new chunk to be used
void CHeap::NewChunk()
{
CChunk *pChunk;
char *pMem;
// allocate memory
pMem = (char*)mem_alloc(sizeof(CChunk)+CHUNK_SIZE, 1);
if(!pMem)
return;
// the chunk structure is located in the begining of the chunk
// init it and return the chunk
pChunk = (CChunk*)pMem;
pChunk->m_pMemory = (char*)(pChunk+1);
pChunk->m_pCurrent = pChunk->m_pMemory;
pChunk->m_pEnd = pChunk->m_pMemory + CHUNK_SIZE;
pChunk->m_pNext = (CChunk *)0x0;
pChunk->m_pNext = m_pCurrent;
m_pCurrent = pChunk;
}
//****************
void *CHeap::AllocateFromChunk(unsigned int Size)
{
char *pMem;
// check if we need can fit the allocation
if(m_pCurrent->m_pCurrent + Size > m_pCurrent->m_pEnd)
return (void*)0x0;
// get memory and move the pointer forward
pMem = m_pCurrent->m_pCurrent;
m_pCurrent->m_pCurrent += Size;
return pMem;
}
// creates a heap
CHeap::CHeap()
{
m_pCurrent = 0x0;
Reset();
}
CHeap::~CHeap()
{
Clear();
}
void CHeap::Reset()
{
Clear();
NewChunk();
}
// destroys the heap
void CHeap::Clear()
{
CChunk *pChunk = m_pCurrent;
CChunk *pNext;
while(pChunk)
{
pNext = pChunk->m_pNext;
mem_free(pChunk);
pChunk = pNext;
}
m_pCurrent = 0x0;
}
//
void *CHeap::Allocate(unsigned Size)
{
char *pMem;
// try to allocate from current chunk
pMem = (char *)AllocateFromChunk(Size);
if(!pMem)
{
// allocate new chunk and add it to the heap
NewChunk();
// try to allocate again
pMem = (char *)AllocateFromChunk(Size);
}
return pMem;
}
|