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Diffstat (limited to 'rt/lio_listio64.c')
-rw-r--r--rt/lio_listio64.c113
1 files changed, 99 insertions, 14 deletions
diff --git a/rt/lio_listio64.c b/rt/lio_listio64.c
index b17e9edae2..19f56adab1 100644
--- a/rt/lio_listio64.c
+++ b/rt/lio_listio64.c
@@ -20,11 +20,20 @@
#include <aio.h>
#include <errno.h>
-#include <semaphore.h>
+#include <stdlib.h>
#include "aio_misc.h"
+/* We need this special structure to handle asynchronous I/O. */
+struct async_waitlist
+ {
+ int counter;
+ struct sigevent sigev;
+ struct waitlist list[0];
+ };
+
+
int
lio_listio64 (mode, list, nent, sig)
int mode;
@@ -32,8 +41,9 @@ lio_listio64 (mode, list, nent, sig)
int nent;
struct sigevent *sig;
{
+ struct requestlist *requests[nent];
int cnt;
- int total = 0;
+ volatile int total = 0;
int result = 0;
/* Check arguments. */
@@ -43,24 +53,99 @@ lio_listio64 (mode, list, nent, sig)
return -1;
}
- /* Request the semaphore. */
- sem_wait (&__aio_requests_sema);
+ /* Request the mutex. */
+ pthread_mutex_lock (&__aio_requests_mutex);
/* Now we can enqueue all requests. Since we already acquired the
- semaphore the enqueue function need not do this. */
+ mutex the enqueue function need not do this. */
for (cnt = 0; cnt < nent; ++cnt)
if (list[cnt] != NULL && list[cnt]->aio_lio_opcode != LIO_NOP)
- if (__aio_enqueue_request ((aiocb_union *) list[cnt],
- list[cnt]->aio_lio_opcode | 128, 0) >= 0)
- /* Successfully enqueued. */
- ++total;
+ {
+ requests[cnt] = __aio_enqueue_request ((aiocb_union *) list[cnt],
+ (list[cnt]->aio_lio_opcode
+ | 128));
+ if (requests[cnt] != NULL)
+ /* Successfully enqueued. */
+ ++total;
+ else
+ /* Signal that we've seen an error. `errno' and the error code
+ of the aiocb will tell more. */
+ result = -1;
+ }
+
+ if (total == 0)
+ {
+ /* We don't have anything to do except signalling if we work
+ asynchronously. */
+ if (mode == LIO_NOWAIT)
+ __aio_notify_only (sig);
+ }
+ else if (mode == LIO_WAIT)
+ {
+ pthread_cond_t cond;
+ struct waitlist waitlist[nent];
+ int oldstate;
+
+ total = 0;
+ for (cnt = 0; cnt < nent; ++cnt)
+ if (list[cnt] != NULL && list[cnt]->aio_lio_opcode != LIO_NOP
+ && requests[cnt] != NULL)
+ {
+ waitlist[cnt].cond = &cond;
+ waitlist[cnt].next = requests[cnt]->waiting;
+ waitlist[cnt].counterp = &total;
+ waitlist[cnt].sigevp = NULL;
+ requests[cnt]->waiting = &waitlist[cnt];
+ ++total;
+ }
+
+ /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancelation
+ points we must be careful. We added entries to the waiting lists
+ which we must remove. So defer cancelation for now. */
+ pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &oldstate);
+
+ while (total > 0)
+ pthread_cond_wait (&cond, &__aio_requests_mutex);
+
+ /* Now it's time to restore the cancelation state. */
+ pthread_setcancelstate (oldstate, NULL);
+ }
+ else
+ {
+ struct async_waitlist *waitlist;
+
+ waitlist = (struct async_waitlist *)
+ malloc (sizeof (struct async_waitlist)
+ + (nent * sizeof (struct waitlist)));
+
+ if (waitlist == NULL)
+ {
+ __set_errno (EAGAIN);
+ result = -1;
+ }
else
- /* Signal that we've seen an error. `errno' and the error code
- of the aiocb will tell more. */
- result = -1;
+ {
+ total = 0;
+
+ for (cnt = 0; cnt < nent; ++cnt)
+ if (list[cnt] != NULL && list[cnt]->aio_lio_opcode != LIO_NOP
+ && requests[cnt] != NULL)
+ {
+ waitlist->list[cnt].cond = NULL;
+ waitlist->list[cnt].next = requests[cnt]->waiting;
+ waitlist->list[cnt].counterp = &waitlist->counter;
+ waitlist->list[cnt].sigevp = &waitlist->sigev;
+ requests[cnt]->waiting = &waitlist->list[cnt];
+ ++total;
+ }
+
+ waitlist->counter = total;
+ waitlist->sigev = *sig;
+ }
+ }
- /* Release the semaphore. */
- sem_post (&__aio_requests_sema);
+ /* Release the mutex. */
+ pthread_mutex_unlock (&__aio_requests_mutex);
return result;
}