Custom Memory Allocator

A thread-safe implementation of a basic memory allocator in C, providing custom malloc() functionality.

Features

• Thread-safe memory allocation using mutex locks
• Free block reuse
• Linked list memory block management
• Memory alignment support

Implementation Details

The allocator uses a linked list of memory blocks, each with a header containing:

• Block size
• Free/occupied status
• Pointer to next block

Key Components

struct head_t {
    size_t size;
    unsigned is_free;
    struct head_t *next;
};

Memory Management Strategy

1. Block Reuse: Searches for existing free blocks before requesting new memory
2. Memory Extension: Uses sbrk() to extend heap when needed
3. Thread Safety: Implements mutex locks for concurrent access

Usage

void *ptr1 = malloc(100);  // Allocate 100 bytes
void *ptr2 = malloc(50);   // Allocate 50 bytes

Building

Compile with pthread support:

gcc -pthread allocator.c -o allocator

Limitations

• No memory coalescing
• No splitting of larger blocks
• Simple first-fit allocation strategy

License

MIT License

Contributing

Pull requests welcome. Please ensure thread safety is maintained in any modifications.