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#include <aio.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include "pthread_impl.h"
#include "libc.h"
struct lio_state {
struct sigevent *sev;
int cnt;
struct aiocb *cbs[];
};
static int lio_wait(struct lio_state *st)
{
int i, err, got_err = 0;
int cnt = st->cnt;
struct aiocb **cbs = st->cbs;
for (;;) {
for (i=0; i<cnt; i++) {
if (!cbs[i]) continue;
err = aio_error(cbs[i]);
if (err==EINPROGRESS)
break;
if (err) got_err=1;
cbs[i] = 0;
}
if (i==cnt) {
if (got_err) {
errno = EIO;
return -1;
}
return 0;
}
if (aio_suspend((void *)cbs, cnt, 0))
return -1;
}
}
static void notify_signal(struct sigevent *sev)
{
siginfo_t si = {
.si_signo = sev->sigev_signo,
.si_value = sev->sigev_value,
.si_code = SI_ASYNCIO,
.si_pid = getpid(),
.si_uid = getuid()
};
__syscall(SYS_rt_sigqueueinfo, si.si_pid, si.si_signo, &si);
}
static void *wait_thread(void *p)
{
struct lio_state *st = p;
struct sigevent *sev = st->sev;
lio_wait(st);
free(st);
switch (sev->sigev_notify) {
case SIGEV_SIGNAL:
notify_signal(sev);
break;
case SIGEV_THREAD:
sev->sigev_notify_function(sev->sigev_value);
break;
}
return 0;
}
int lio_listio(int mode, struct aiocb *restrict const *restrict cbs, int cnt, struct sigevent *restrict sev)
{
int i, ret;
struct lio_state *st=0;
if (cnt < 0) {
errno = EINVAL;
return -1;
}
if (mode == LIO_WAIT || (sev && sev->sigev_notify != SIGEV_NONE)) {
if (!(st = malloc(sizeof *st + cnt*sizeof *cbs))) {
errno = EAGAIN;
return -1;
}
st->cnt = cnt;
st->sev = sev;
memcpy(st->cbs, (void*) cbs, cnt*sizeof *cbs);
}
for (i=0; i<cnt; i++) {
if (!cbs[i]) continue;
switch (cbs[i]->aio_lio_opcode) {
case LIO_READ:
ret = aio_read(cbs[i]);
break;
case LIO_WRITE:
ret = aio_write(cbs[i]);
break;
default:
continue;
}
if (ret) {
free(st);
errno = EAGAIN;
return -1;
}
}
if (mode == LIO_WAIT) {
ret = lio_wait(st);
free(st);
return ret;
}
if (st) {
pthread_attr_t a;
sigset_t set;
pthread_t td;
if (sev->sigev_notify == SIGEV_THREAD) {
if (sev->sigev_notify_attributes)
a = *sev->sigev_notify_attributes;
else
pthread_attr_init(&a);
} else {
pthread_attr_init(&a);
pthread_attr_setstacksize(&a, PAGE_SIZE);
pthread_attr_setguardsize(&a, 0);
}
pthread_attr_setdetachstate(&a, PTHREAD_CREATE_DETACHED);
sigfillset(&set);
pthread_sigmask(SIG_BLOCK, &set, &set);
if (pthread_create(&td, &a, wait_thread, st)) {
free(st);
errno = EAGAIN;
return -1;
}
pthread_sigmask(SIG_SETMASK, &set, 0);
}
return 0;
}
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