Sort an array, passing a userdata pointer to the compare function.
Defined in <SDL3/SDL_stdinc.h>
void SDL_qsort_r(void *base, size_t nmemb, size_t size, SDL_CompareCallback_r compare, void *userdata);| 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_r | compare | a function used to compare elements in the array. |
| void * | userdata | a pointer to pass to the compare function. |
For example:
typedef enum {
sort_increasing,
sort_decreasing,
} sort_method;
typedef struct {
int key;
const char *string;
} data;
int SDLCALL compare(const void *userdata, const void *a, const void *b)
{
sort_method method = (sort_method)(uintptr_t)userdata;
const data *A = (const data *)a;
const data *B = (const data *)b;
if (A->key < B->key) {
return (method == sort_increasing) ? -1 : 1;
} else if (B->key < A->key) {
return (method == sort_increasing) ? 1 : -1;
} else {
return 0;
}
}
data values[] = {
{ 3, "third" }, { 1, "first" }, { 2, "second" }
};
SDL_qsort_r(values, SDL_arraysize(values), sizeof(values[0]), compare, (const void *)(uintptr_t)sort_increasing);It is safe to call this function from any thread.
This function is available since SDL 3.1.3.