From 1e5f6af0c7deda7a101d9842fba78682f5c7aa0c Mon Sep 17 00:00:00 2001
From: "Mark D. Roth" <roth@google.com>
Date: Fri, 7 Oct 2016 08:32:58 -0700
Subject: [PATCH] Fix grpclb LB policy pick method to return 0 upon error.
---
src/core/ext/client_config/lb_policy.h | 21 ++++++++++++---------
src/core/ext/lb_policy/grpclb/grpclb.c | 2 +-
2 files changed, 13 insertions(+), 10 deletions(-)
diff --git a/src/core/ext/client_config/lb_policy.h b/src/core/ext/client_config/lb_policy.h
index 6cc3e1ebd3..110d08fcac 100644
--- a/src/core/ext/client_config/lb_policy.h
+++ b/src/core/ext/client_config/lb_policy.h
@@ -142,15 +142,18 @@ void grpc_lb_policy_weak_unref(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy);
void grpc_lb_policy_init(grpc_lb_policy *policy,
const grpc_lb_policy_vtable *vtable);
-/** Find an appropriate target for this call, based on \a pick_args.
- Picking can be synchronous or asynchronous. In the synchronous case, when a
- pick is readily available, it'll be returned in \a target and a non-zero
- value will be returned.
- In the asynchronous case, zero is returned and \a on_complete will be called
- once \a target and \a user_data have been set. Any IO should be done under
- \a pick_args->pollent. The opaque \a user_data output argument corresponds
- to information that may need be propagated from the LB policy. It may be
- NULL. Errors are signaled by receiving a NULL \a *target. */
+/** Finds an appropriate subchannel for a call, based on \a pick_args.
+
+ \a target will be set to the selected subchannel, or NULL on failure.
+ Upon success, \a user_data will be set to whatever opaque information
+ may need to be propagated from the LB policy, or NULL if not needed.
+
+ If the pick succeeds and a result is known immediately, a non-zero
+ value will be returned. Otherwise, \a on_complete will be invoked
+ once the pick is complete with its error argument set to indicate
+ success or failure.
+
+ Any I/O should be done under \a pick_args->pollent. */
int grpc_lb_policy_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *policy,
const grpc_lb_policy_pick_args *pick_args,
grpc_connected_subchannel **target, void **user_data,
diff --git a/src/core/ext/lb_policy/grpclb/grpclb.c b/src/core/ext/lb_policy/grpclb/grpclb.c
index 63af774ea6..ae1f2a3b4c 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/lb_policy/grpclb/grpclb.c
@@ -761,7 +761,7 @@ static int glb_pick(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
GRPC_ERROR_CREATE("No mdelem storage for the LB token. Load reporting "
"won't work without it. Failing"),
NULL);
- return 1;
+ return 0;
}
glb_lb_policy *glb_policy = (glb_lb_policy *)pol;
--
GitLab