[CLEANUP] use distinct bits per load-balancing algorithm type
It's useful to be able to check against an LB algorithm type by
testing just one bit.
diff --git a/include/types/backend.h b/include/types/backend.h
index 536f453..e392a7b 100644
--- a/include/types/backend.h
+++ b/include/types/backend.h
@@ -24,14 +24,24 @@
#include <common/config.h>
-/* Parameters for proxy->lbprm.algo. Those values are exclusive */
-#define BE_LB_ALGO_RR 0x00000001 /* balance in round-robin mode */
-#define BE_LB_ALGO_SH 0x00000002 /* balance on source IP hash */
-#define BE_LB_ALGO_L4 0x00000003 /* mask to match layer4-based algorithms */
-#define BE_LB_ALGO_UH 0x00000004 /* balance on URI hash */
-#define BE_LB_ALGO_PH 0x00000005 /* balance on URL parameter hash */
-#define BE_LB_ALGO_L7 0x00000004 /* mask to match layer7-based algorithms */
-#define BE_LB_ALGO 0x00000007 /* mask to extract BALANCE algorithm */
+/* Parameters for proxy->lbprm.algo.
+ * The low part of the value is unique for each algo so that applying the mask
+ * BE_LB_ALGO returns a unique algorithm.
+ * The high part indicates specific properties.
+ */
+
+/* Masks to extract algorithm properties */
+#define BE_LB_ALGO 0x000007FF /* mask to extract all algorithm flags */
+#define BE_LB_PROP_DYN 0x00000100 /* mask to match dynamic algorithms */
+#define BE_LB_PROP_L4 0x00000200 /* mask to match layer4-based algorithms */
+#define BE_LB_PROP_L7 0x00000400 /* mask to match layer7-based algorithms */
+
+/* the algorithms themselves */
+#define BE_LB_ALGO_NONE 0x00000000 /* dispatch or transparent mode */
+#define BE_LB_ALGO_RR (BE_LB_PROP_DYN | 0x01) /* fast weighted round-robin mode (dynamic) */
+#define BE_LB_ALGO_SH (BE_LB_PROP_L4 | 0x02) /* balance on source IP hash */
+#define BE_LB_ALGO_UH (BE_LB_PROP_L7 | 0x03) /* balance on URI hash */
+#define BE_LB_ALGO_PH (BE_LB_PROP_L7 | 0x04) /* balance on URL parameter hash */
/* various constants */
#define BE_WEIGHT_SCALE 256 /* scale between user weight and effective weight */