[pulseaudio-discuss] [PATCH] bluetooth: Refactor POLLHUP handling

[Tanu Kaskinen]

The code in the "io_fail" section was only used for HUP handling, but
there were jumps to there also from places where reading or writing
failed, because the read/write failure could have been caused by HUP.
This patch simplifies things by checking for HUP condition before
trying to read or write. Now if reading or writing fails, we will
jump to "fail" directly instead of going via the "io_fail" label. As
a result, the "io_fail" label isn't needed any more.
---
 src/modules/bluetooth/module-bluez5-device.c | 48 ++++++++++++----------------
 1 file changed, 20 insertions(+), 28 deletions(-)

diff --git a/src/modules/bluetooth/module-bluez5-device.c b/src/modules/bluetooth/module-bluez5-device.c
index 7e6b237..57b2791 100644
--- a/src/modules/bluetooth/module-bluez5-device.c
+++ b/src/modules/bluetooth/module-bluez5-device.c
@@ -1082,6 +1082,24 @@ static void thread_func(void *userdata) {
 
         pollfd = u->rtpoll_item ? pa_rtpoll_item_get_pollfd(u->rtpoll_item, NULL) : NULL;
 
+        if (pollfd && (pollfd->revents & ~(POLLOUT|POLLIN))) {
+            pa_log_info("FD error: %s%s%s%s",
+                        pollfd->revents & POLLERR ? "POLLERR " :"",
+                        pollfd->revents & POLLHUP ? "POLLHUP " :"",
+                        pollfd->revents & POLLPRI ? "POLLPRI " :"",
+                        pollfd->revents & POLLNVAL ? "POLLNVAL " :"");
+
+            if (pollfd->revents & POLLHUP) {
+                pollfd = NULL;
+                teardown_stream(u);
+                do_write = 0;
+                pending_read_bytes = 0;
+                writable = false;
+                pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->msg), BLUETOOTH_MESSAGE_STREAM_FD_HUP, NULL, 0, NULL, NULL);
+            } else
+                goto fail;
+        }
+
         if (u->source && PA_SOURCE_IS_LINKED(u->source->thread_info.state)) {
 
             /* We should send two blocks to the device before we expect
@@ -1096,7 +1114,7 @@ static void thread_func(void *userdata) {
                 n_read = a2dp_process_push(u);
 
                 if (n_read < 0)
-                    goto io_fail;
+                    goto fail;
 
                 if (n_read > 0) {
                     /* We just read something, so we are supposed to write something, too */
@@ -1165,7 +1183,7 @@ static void thread_func(void *userdata) {
                         u->started_at = pa_rtclock_now();
 
                     if ((n_written = a2dp_process_render(u)) < 0)
-                        goto io_fail;
+                        goto fail;
 
                     if (n_written == 0)
                         pa_log("Broken kernel: we got EAGAIN on write() after POLLOUT!");
@@ -1212,32 +1230,6 @@ static void thread_func(void *userdata) {
             transport_release(u);
             goto finish;
         }
-
-        pollfd = u->rtpoll_item ? pa_rtpoll_item_get_pollfd(u->rtpoll_item, NULL) : NULL;
-
-        if (pollfd && (pollfd->revents & ~(POLLOUT|POLLIN))) {
-            pa_log_info("FD error: %s%s%s%s",
-                        pollfd->revents & POLLERR ? "POLLERR " :"",
-                        pollfd->revents & POLLHUP ? "POLLHUP " :"",
-                        pollfd->revents & POLLPRI ? "POLLPRI " :"",
-                        pollfd->revents & POLLNVAL ? "POLLNVAL " :"");
-            goto io_fail;
-        }
-
-        continue;
-
-io_fail:
-        /* In case of HUP, just tear down the streams */
-        if (!pollfd || (pollfd->revents & POLLHUP) == 0)
-            goto fail;
-
-        do_write = 0;
-        pending_read_bytes = 0;
-        writable = false;
-
-        pa_asyncmsgq_post(pa_thread_mq_get()->outq, PA_MSGOBJECT(u->msg), BLUETOOTH_MESSAGE_STREAM_FD_HUP, NULL, 0, NULL, NULL);
-
-        teardown_stream(u);
     }
 
 fail:
-- 
1.9.3