control.c: snd_ctl_wait: fix revents handling

The revents parameter of snd_ctl_poll_descriptors_revents() is a single
value, not an array.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

diff --git a/src/control/control.c b/src/control/control.c
index c9b04a1bdb48c76427da349953eb5cf8fd9b465d..ae70e7668c36f50564a1ea6e9b03486a111f5182 100644 (file)
--- a/src/control/control.c
+++ b/src/control/control.c
@@ -674,8 +674,8 @@ int snd_ctl_read(snd_ctl_t *ctl, snd_ctl_event_t *event)
 int snd_ctl_wait(snd_ctl_t *ctl, int timeout)
 {
        struct pollfd *pfd;
-       unsigned short *revents;
-       int i, npfds, pollio, err, err_poll;
+       unsigned short revents;
+       int i, npfds, err, err_poll;
 
        npfds = snd_ctl_poll_descriptors_count(ctl);
        if (npfds <= 0 || npfds >= 16) {
@@ -683,7 +683,6 @@ int snd_ctl_wait(snd_ctl_t *ctl, int timeout)
                return -EIO;
        }
        pfd = alloca(sizeof(*pfd) * npfds);
-       revents = alloca(sizeof(*revents) * npfds);
        err = snd_ctl_poll_descriptors(ctl, pfd, npfds);
        if (err < 0)
                return err;
@@ -691,26 +690,20 @@ int snd_ctl_wait(snd_ctl_t *ctl, int timeout)
                SNDMSG("invalid poll descriptors %d\n", err);
                return -EIO;
        }
-       do {
+       for (;;) {
                err_poll = poll(pfd, npfds, timeout);
                if (err_poll < 0)
                        return -errno;
                if (! err_poll)
-                       break;
-               err = snd_ctl_poll_descriptors_revents(ctl, pfd, npfds, revents);
+                       return 0;
+               err = snd_ctl_poll_descriptors_revents(ctl, pfd, npfds, &revents);
                if (err < 0)
                        return err;
-               pollio = 0;
-               for (i = 0; i < npfds; i++) {
-                       if (revents[i] & (POLLERR | POLLNVAL))
-                               return -EIO;
-                       if ((revents[i] & (POLLIN | POLLOUT)) == 0)
-                               continue;
-                       pollio++;
-               }
-       } while (! pollio);
-
-       return err_poll > 0 ? 1 : 0;
+               if (revents & (POLLERR | POLLNVAL))
+                       return -EIO;
+               if (revents & (POLLIN | POLLOUT))
+                       return 1;
+       }
 }
 
 /**