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/**
* @file malloc.c
* @brief malloc implementation.
*/
#include "malloc.h"
#include "malloc_internal.h"
t_heap g_heap = { 0 };
static t_chunk *
_s_find_free_chunk (t_zone *zone, size_t aligned_size)
{
t_chunk *chunk;
chunk = (t_chunk *)((char *)zone + ALIGN (sizeof (t_zone)));
while (chunk)
{
if (chunk->is_free && chunk->size >= aligned_size)
return (chunk);
chunk = chunk->next;
}
return (NULL);
}
static void
_s_split_chunk (t_chunk *chunk, size_t aligned_size)
{
t_chunk *remainder;
size_t min_split;
min_split = ALIGN (sizeof (t_chunk)) + ALIGNMENT;
if (chunk->size >= aligned_size + min_split)
{
remainder = (t_chunk *)((char *)chunk + ALIGN (sizeof (t_chunk))
+ aligned_size);
remainder->size = chunk->size - aligned_size - ALIGN (sizeof (t_chunk));
remainder->next = chunk->next;
remainder->is_free = 1;
chunk->size = aligned_size;
chunk->next = remainder;
}
chunk->is_free = 0;
}
void *
malloc (size_t size)
{
t_zone **zone_list;
t_zone *zone;
t_chunk *chunk;
size_t alloc_max;
size_t aligned_size;
if (size == 0)
size = 1;
if (size <= TINY_MAX)
{
zone_list = &g_heap.tiny;
alloc_max = TINY_MAX;
}
else if (size <= SMALL_MAX)
{
zone_list = &g_heap.small;
alloc_max = SMALL_MAX;
}
else
{
zone_list = &g_heap.large;
alloc_max = size;
}
aligned_size = ALIGN (size);
chunk = NULL;
zone = *zone_list;
while (zone && !chunk)
{
chunk = _s_find_free_chunk (zone, aligned_size);
if (!chunk)
zone = zone->next;
}
if (!chunk)
{
zone = zone_new (alloc_max);
if (!zone)
return (NULL);
zone->next = *zone_list;
*zone_list = zone;
chunk = _s_find_free_chunk (zone, aligned_size);
}
_s_split_chunk (chunk, aligned_size);
return ((char *)chunk + ALIGN (sizeof (t_chunk)));
}
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