/my-malloc

Primary LanguageC

Custom Memory Allocation Library

The inspiration for this project was my Operating Systems class at BBU, Babeș-Bolyai University, during which, I got my hands on the Standard Library Memory Allocator. Using the knowledge obtained then, I created my humble version of the memory allocator, which thrives not in efficiency, but in being my very own shot at it. However, a great source of inspiration was this article.

Building the Project

To build the project, run the build.sh script:

./build.sh

Usage

Include the malloc.h header in your C program:

#include "malloc.h"

Functionalities

  1. void *my_malloc(size_t nsize) - allocates a block of memory of the specified size
  2. void my_free(void *block) - frees a previously allocated block of memory
  3. void *my_calloc(size_t num, size_t nsize) - allocates memory for an array of elements and initializes them to zero
  4. void *my_realloc(void *block, size_t nsize) - changes the size of a previously allocated memory block

Implementation Details

  • Concurrency - in order to avoid race conditions (different processes read and write the same memory blocks simultaneously), I used pthread_mutex_lock, that ensures mutual exclusivity for one process to the memory block.
  • Memory Acquisition - my implementation uses the system call void *sbrk(int incr) to increase or decrease the program's data segment size and therefore, request more memory from the operating system.
  • Memory Representation - the allocator maintains a singly linked list of all memory blocks, both allocated and free.