tiny_alloc_c

A very simple memory allocation implementation in pure C.

• Usage
• Features
• Examples
• License

Usage

Useless, but funny

Features

• talloc - allocating memory
• trealloc - reallocating memory
• tfree - freeing allocated memory
• talloc_heap_view - printing the heap and chunks info

talloc

void* talloc(size_t count);

A function that allocates an amount of memory equal to count. Returns 0 if the function fails for some reason.

If the function returns 0, it is usually due to the virtual heap size being too small. You can change its size by modifying TALLOC_MAX_HEAP_SIZE.

By default, this value is 1024 * 1024 * 4, which is 4 megabytes (mebibytes).

If this is the first call to this function, it initializes the heap, and an assert is triggered in case of failure.

If copyOld is equal to zero, then the memory from pointer will not be copied and cleared.

trealloc

void* trealloc(void* pointer, size_t count, const int copyOld);

Reallocates memory for pointer with a size of count.

If the function returns 0, it is usually due to the virtual heap size being too small. You can change its size by modifying TALLOC_MAX_HEAP_SIZE.

If this is the first call to this function, it initializes the heap, and an assert is triggered in case of failure.

tfree

void tfree(void* pointer);

Deallocates the memory allocated for pointer.

If for some reason the function cannot free the memory for this pointer, it does nothing.

talloc_heap_view

void talloc_heap_view();

Prints to stdout basic information about the heap and chunks used for the operation of the talloc and tfree functions.

If this is the first call to this function, it initializes the heap, and an assert is triggered in case of failure.

Examples

#define TALLOC_IMPLEMENTATION
#include "tiny_alloc_single_header.h"
#include <stdio.h>
#include <string.h>

int main() {
    char* pointer1 = talloc(128);
    char* pointer2 = talloc(51);
    assert(pointer1 != 0);
    assert(pointer2 != 0);
    strcpy(pointer1, "beleberda bum bim brbrbrbbrbr !!!---");
    strcpy(pointer2, "beleberda bum bim brbrbrbbrbr !!!--- part two! pis");
    printf("%s\n", pointer1);
    printf("%s\n", pointer2);
    tfree(pointer2);
    tfree(pointer1);

    return 0;
}

A huge thank you to the creator(s) of stb_image for providing the wonderful opportunity to test my wacky ideas.

#define TALLOC_IMPLEMENTATION
#define TALLOC_TESTING
#define TALLOC_MAX_HEAP_SIZE (1024 * 1024 * 8)
#include "tiny_alloc_single_header.h"

#define STB_IMAGE_IMPLEMENTATION
#define STBI_MALLOC talloc
#define STBI_FREE tfree
#define STBI_REALLOC trealloc
#include "stb_image.h"

#include <stdio.h>

int main() {
    int x;
    int y;
    int c;
    stbi_uc* data = stbi_load("F:/projects/tiny_malloc/image.jpg", &x, &y, &c, 3);
    assert(data != 0);
    // stbi for SOME REASON allocates (x * y * c) + 1 bytes for jpeg images
    talloc_heap_view();
    stbi_image_free(data);
    printf("%s", "success");
    return 0;
}

License

This library is licensed under the MIT License. See the LICENSE file for more details.