commit 641275e1bdbb0fb863911aa93eba40f1e4358b70
author Haynes Mathew George <hgeorge@codeaurora.org> Fri Jul 15 18:29:32 2016 -0700
committer Eric Laurent <elaurent@google.com> Tue Jul 19 11:38:56 2016 -0700
tree f3594853c90bb541533dfeb8c4077139d874b564
parent 8721b4dfc191381d71f4839f2081fe9328157579

sndmonitor: treat errors during poll

Bug: 30075678
Change-Id: I5e17c1def67b5c71461b43bee83a06e2126e29bb

hal/audio_extn/sndmonitor.c

diff --git a/hal/audio_extn/sndmonitor.c b/hal/audio_extn/sndmonitor.c
index 4b6332c..d303c06 100644
--- a/hal/audio_extn/sndmonitor.c
+++ b/hal/audio_extn/sndmonitor.c
@@ -430,8 +430,19 @@
 
     while (1) {
         if (poll(pfd, num_poll_fds, -1) < 0) {
+            int errno_ = errno;
             ALOGE("poll() failed w/ err %s", strerror(errno));
-            break;
+            switch (errno_) {
+            case EINTR:
+            case ENOMEM:
+                sleep(2);
+                continue;
+            default:
+                /* above errors can be caused due to current system
+                   state .. any other error is not expected */
+                LOG_ALWAYS_FATAL("unxpected poll() system call failure");
+                break;
+            }
         }
         ALOGV("out of poll()");
 
@@ -446,6 +457,11 @@
                 break;
         } else if (ERROR_IN_FD(&pfd[0])) {
             // do not consider for poll again
+            // POLLERR - can this happen?
+            // POLLHUP - adev must not close pipe
+            // POLLNVAL - fd is valid
+            LOG_ALWAYS_FATAL("unxpected error in pipe poll fd 0x%x",
+                             pfd[0].revents);
             pfd[0].fd *= -1;
         }
 
@@ -456,6 +472,11 @@
                 on_sndcard_state_update(s);
             else if (ERROR_IN_FD(&pfd[i])) {
                 // do not consider for poll again
+                // POLLERR - can this happen as we are reading from a fs?
+                // POLLHUP - not valid for cardN/state
+                // POLLNVAL - fd is valid
+                LOG_ALWAYS_FATAL("unxpected error in card poll fd 0x%x",
+                                 pfd[i].revents);
                 pfd[i].fd *= -1;
             }
             ++i;
@@ -467,11 +488,17 @@
                 on_dev_event(d);
             else if (ERROR_IN_FD(&pfd[i])) {
                 // do not consider for poll again
+                // POLLERR - can this happen as we are reading from a fs?
+                // POLLHUP - not valid for switch/state
+                // POLLNVAL - fd is valid
+                LOG_ALWAYS_FATAL("unxpected error in dev poll fd 0x%x",
+                                 pfd[i].revents);
                 pfd[i].fd *= -1;
             }
             ++i;
         }
     }
+
     return NULL;
 }