53 lines
1.0 KiB
C++
53 lines
1.0 KiB
C++
#include <memory.h>
|
|
#include <algorithm>
|
|
#include <stdlib.h>
|
|
#include "block_allocator.h"
|
|
|
|
block_allocator::block_allocator(size_t blocksize)
|
|
: m_head(0), m_blocksize(blocksize)
|
|
{
|
|
}
|
|
|
|
block_allocator::~block_allocator()
|
|
{
|
|
while (m_head)
|
|
{
|
|
block *temp = m_head->next;
|
|
::free(m_head);
|
|
m_head = temp;
|
|
}
|
|
}
|
|
|
|
void block_allocator::swap(block_allocator &rhs)
|
|
{
|
|
std::swap(m_blocksize, rhs.m_blocksize);
|
|
std::swap(m_head, rhs.m_head);
|
|
}
|
|
|
|
void *block_allocator::malloc(size_t size)
|
|
{
|
|
if ((m_head && m_head->used + size > m_head->size) || !m_head)
|
|
{
|
|
// calc needed size for allocation
|
|
size_t alloc_size = std::max(sizeof(block) + size, m_blocksize);
|
|
|
|
// create new block
|
|
char *buffer = (char *)::malloc(alloc_size);
|
|
block *b = reinterpret_cast<block *>(buffer);
|
|
b->size = alloc_size;
|
|
b->used = sizeof(block);
|
|
b->buffer = buffer;
|
|
b->next = m_head;
|
|
m_head = b;
|
|
}
|
|
|
|
void *ptr = m_head->buffer + m_head->used;
|
|
m_head->used += size;
|
|
return ptr;
|
|
}
|
|
|
|
void block_allocator::free()
|
|
{
|
|
block_allocator(0).swap(*this);
|
|
}
|