[CLEANUP] get rid of BF_SHUT*_PENDING
BF_SHUTR_PENDING and BF_SHUTW_PENDING were poor ideas because
BF_SHUTR is the pending of BF_SHUTW_DONE and BF_SHUTW is the
pending of BF_SHUTR_DONE. Remove those two useless and confusing
"pending" versions and rename buffer_shut{r,w}_* functions.
diff --git a/include/types/buffers.h b/include/types/buffers.h
index 8319010..be93693 100644
--- a/include/types/buffers.h
+++ b/include/types/buffers.h
@@ -28,13 +28,8 @@
/* The BF_* macros designate Buffer Flags, which may be ORed in the bit field
* member 'flags' in struct buffer.
*/
-#define BF_SHUTR_PENDING 1 /* ignored if BF_SHUTW_DONE */
-#define BF_SHUTR_DONE 2 /* takes precedence over BF_SHUTR_PENDING */
-#define BF_SHUTR_STATUS (BF_SHUTR_PENDING|BF_SHUTR_DONE)
-
-#define BF_SHUTW_PENDING 4 /* ignored if BF_SHUTW_DONE */
-#define BF_SHUTW_DONE 8 /* takes precedence over BF_SHUTW_PENDING */
-#define BF_SHUTW_STATUS (BF_SHUTW_PENDING|BF_SHUTW_DONE)
+#define BF_SHUTR 4 /* producer has already shut down */
+#define BF_SHUTW 8 /* consumer has already shut down */
#define BF_PARTIAL_READ 16
#define BF_COMPLETE_READ 32