Custom Memory Allocator inspired by the Buddy System

An educational project written in C

This project includes allocate_memory and free_memory functions similar to the standard library's malloc and free. Before allocating memory, the allocator must be initialized with initialize_memory_allocator.

Key Points

• Memory is allocated in static memory (not the heap)
• This is not a true Buddy System implementation¹

Example code

initialize_memory_allocator();

// Allocating memory for 5 int elements
int *a = allocate_memory(sizeof(int) * 5);

// Initializing dynamic array with data
for (int i = 0; i < 5; i++)
{
    a[i] = i;
}

// Printing dynamic array values
for (int i = 0; i < 5; i++)
{
    printf("Value at index %d: %d\n", i, a[i]);
}

// Freeing after use
free_memory(a);

Free memory Structure

The following code example would produce a binary tree structure as shown below:

// in this example 
// sizeof(BlockHeader) = 24
// MEMORY_POOL_SIZE = 1024

initialize_memory_allocator();

int *a = allocate_memory(214);

The actual block size in this implementation is smaller than expected because each block must include not only the free memory space but also the metadata of the BlockHeader struct². This metadata is essential for navigating the binary tree.

Additional Information

Footnotes

1. While this project is inspired by the Buddy System, it does not implement a true Buddy System because a true Buddy System's block size must be a power of two. ↩

2. In order to have a true Buddy System structure, the metadata of the struct would need to be stored elsewhere. ↩