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#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include "til_setup.h"
/* Allocate and initialize a new til_setup_t of size bytes.
* free_func is assigned to til_setup_t.free, and will be used for freeing the
* instance returned when destroyed. If free_func is NULL, free() will be
* used by default.
*
* Note this returns void * despite creating a til_setup_t, this is for convenience
* as the callers are generally using it in place of calloc(), and assign it to a
* container struct of some other type but having an embedded til_setup_t.
*/
void * til_setup_new(size_t size, void (*free_func)(til_setup_t *setup))
{
til_setup_t *setup;
assert(size >= sizeof(til_setup_t));
setup = calloc(1, size);
if (!setup)
return NULL;
setup->refcount = 1;
setup->free = free_func;
return setup;
}
/* bump refcount on setup */
void * til_setup_ref(til_setup_t *setup)
{
assert(setup);
setup->refcount++;
return setup;
}
/* unref setup, freeing it when refcount reaches zero.
* returns NULL if setup is freed (including when NULL was supplied for setup)
* resturns setup when setup persists.
* the public api is to just use til_setup_free() and discard that information,
* but this is kept here as distinct for potential debugging purposes.
*/
static void * til_setup_unref(til_setup_t *setup)
{
if (!setup)
return NULL;
assert(setup->refcount > 0);
setup->refcount--;
if (!setup->refcount) {
if (setup->free)
setup->free(setup);
else
free(setup);
return NULL;
}
return setup;
}
/* like til_setup_unref() except always returns NULL so you
* can't tell if it was actually freed or not, but this is sometimes
* a convenient free-style wrapper if you have to NULL-assign a placeholder.
*/
void * til_setup_free(til_setup_t *setup)
{
(void) til_setup_unref(setup);
return NULL;
}
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