SDL_bsearch

Perform a binary search on a previously sorted array.

Header File

Syntax

void * SDL_bsearch(const void *key, const void *base, size_t nmemb, size_t size, SDL_CompareCallback compare);

Function Parameters

const void *	key	a pointer to a key equal to the element being searched for.
const void *	base	a pointer to the start of the array.
size_t	nmemb	the number of elements in the array.
size_t	size	the size of the elements in the array.
SDL_CompareCallback	compare	a function used to compare elements in the array.

Return Value

(void *) Returns a pointer to the matching element in the array, or NULL if not found.

Remarks

For example:

typedef struct {
    int key;
    const char *string;
} data;

int SDLCALL compare(const void *a, const void *b)
{
    const data *A = (const data *)a;
    const data *B = (const data *)b;

    if (A->n < B->n) {
        return -1;
    } else if (B->n < A->n) {
        return 1;
    } else {
        return 0;
    }
}

data values[] = {
    { 1, "first" }, { 2, "second" }, { 3, "third" }
};
data key = { 2, NULL };

data *result = SDL_bsearch(&key, values, SDL_arraysize(values), sizeof(values[0]), compare);

Thread Safety

It is safe to call this function from any thread.

Version

This function is available since SDL 3.2.0.