dmmlib/custom_malloc.c

#include "custom_malloc.h"
#include "posix_lock.h"
#include "other.h"
#include "sys_alloc.h"

void * custom_malloc(heap_t* heap, size_t size) {
	leaHdr *ptr;
	int fixed_list_id, i, found;
	MAPTABLE_NODE *current_maptable_node;
	leaHdr *current_node;

	ptr = NULL;

	posix_lock(heap);

	fixed_list_id = map_size_to_list(heap, size);
	
	// If a fixed list is found, do a first fit
	if(fixed_list_id != -1) {
		current_maptable_node = heap->maptable_head;
		// traverse through the maptable node list
		if(fixed_list_id != 0) {
			for(i = 1; i < fixed_list_id; i++) {
				current_maptable_node = current_maptable_node->next;
			}
		}
		if(current_maptable_node->fixed_list_head != NULL) {
			ptr = current_maptable_node->fixed_list_head;
			current_maptable_node->fixed_list_head = ptr->next;
			set_requested_size(ptr, size);
			markInUse(ptr);
		}
	}

	if(ptr == NULL) {
		found = 0;

		// first fit from free list
		current_node = heap->free_list_head;

		if(current_node != NULL && getSize(current_node) >= size) {
			ptr = current_node;
			heap->free_list_head = ptr->next;
			set_requested_size(ptr, size);
			markInUse(ptr);
		}
		while(current_node && !found) {
			if(getSize(current_node->next) >= size) {
				ptr = current_node->next;
				current_node->next = ptr->next;
				set_requested_size(ptr, size);
				markInUse(ptr);
				found = 1;
			}
			current_node = current_node->next;
		}

		if(!found) {
			posix_unlock(heap);
			return sys_alloc(size);
		}

	}

	posix_unlock(heap);
	return ptr;
}