X-Git-Url: https://git.distorted.org.uk/~mdw/disorder/blobdiff_plain/67895023d60fc492720d2f575045ed0173948947..d76bbdea349bf3856172ce9599e657d566e91162:/lib/uaudio.h

diff --git a/lib/uaudio.h b/lib/uaudio.h
index aa686d0..d6376c8 100644
--- a/lib/uaudio.h
+++ b/lib/uaudio.h
@@ -34,6 +34,15 @@ extern size_t uaudio_sample_size;
  * @param max_samples How many samples to supply
  * @param userdata As passed to uaudio_open()
  * @return Number of samples filled
+ *
+ * This function should not block if possible (better to fill the buffer with
+ * 0s) and should definitely not block indefinitely.  This great caution with
+ * any locks or syscalls!  In particular avoid it taking a lock that may be
+ * held while any of the @ref uaudio members are called.
+ *
+ * If it's more convenient, it's OK to return less than the maximum number of
+ * samples (including 0) provided you expect to be called again for more
+ * samples immediately.
  */
 typedef size_t uaudio_callback(void *buffer,
                                size_t max_samples,
@@ -127,7 +136,17 @@ void uaudio_thread_start(uaudio_callback *callback,
 			 void *userdata,
 			 uaudio_playcallback *playcallback,
 			 size_t min,
-                         size_t max);
+                         size_t max,
+                         unsigned flags);
+
+/** @brief Fake pauses
+ *
+ * This flag is used for audio backends that cannot sensibly be paused.
+ * The thread support code will supply silence while deactivated in this
+ * case.
+ */
+#define UAUDIO_THREAD_FAKE_PAUSE 0x00000001
+
 void uaudio_thread_stop(void);
 void uaudio_thread_activate(void);
 void uaudio_thread_deactivate(void);