metal-cos/lib/libc/exit.c
2023-10-02 19:33:47 -04:00

48 lines
811 B
C

#include <stdint.h>
#include <stdlib.h>
#include <syscall.h>
struct atexit_cb {
struct atexit_cb *next;
void (*cb)(void);
};
static uint64_t _atexit_count = 0;
static struct atexit_cb _atexits[32]; // POSIX requires at least 32 atexit functions
static struct atexit_cb *_atexit_last = NULL;
int
atexit(void (*function)(void))
{
if (_atexit_count < 32) {
struct atexit_cb *prev = _atexit_last;
_atexits[_atexit_count].cb = function;
_atexits[_atexit_count].next = prev;
_atexit_last = &_atexits[_atexit_count];
_atexit_count++;
} else {
// XXX: Support malloc
return -1;
}
return 0;
}
void
exit(int status)
{
while (_atexit_last != NULL) {
(_atexit_last->cb)();
_atexit_last = _atexit_last->next;
}
OSExit(status & 0x00ff);
__builtin_unreachable();
}