Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2015, Google Inc. |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions are |
| 8 | * met: |
| 9 | * |
| 10 | * * Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * * Redistributions in binary form must reproduce the above |
| 13 | * copyright notice, this list of conditions and the following disclaimer |
| 14 | * in the documentation and/or other materials provided with the |
| 15 | * distribution. |
| 16 | * * Neither the name of Google Inc. nor the names of its |
| 17 | * contributors may be used to endorse or promote products derived from |
| 18 | * this software without specific prior written permission. |
| 19 | * |
| 20 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 21 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 22 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 23 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| 24 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| 25 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| 26 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 27 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 28 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 29 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| 30 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 31 | * |
| 32 | */ |
| 33 | |
| 34 | #ifndef GRPC_INTERNAL_CORE_CLIENT_CONFIG_LB_POLICY_H |
| 35 | #define GRPC_INTERNAL_CORE_CLIENT_CONFIG_LB_POLICY_H |
| 36 | |
Craig Tiller | af69180 | 2015-06-23 14:57:07 -0700 | [diff] [blame] | 37 | #include "src/core/client_config/subchannel.h" |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 38 | |
| 39 | /** A load balancing policy: specified by a vtable and a struct (which |
| 40 | is expected to be extended to contain some parameters) */ |
| 41 | typedef struct grpc_lb_policy grpc_lb_policy; |
| 42 | typedef struct grpc_lb_policy_vtable grpc_lb_policy_vtable; |
| 43 | |
Craig Tiller | 7df28a7 | 2015-06-24 09:23:52 -0700 | [diff] [blame] | 44 | typedef void (*grpc_lb_completion)(void *cb_arg, grpc_subchannel *subchannel, |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 45 | grpc_status_code status, const char *errmsg); |
| 46 | |
Craig Tiller | 7c0b4d7 | 2015-06-25 14:44:44 -0700 | [diff] [blame] | 47 | struct grpc_lb_policy { |
Craig Tiller | eb3b12e | 2015-06-26 14:42:49 -0700 | [diff] [blame] | 48 | const grpc_lb_policy_vtable *vtable; |
Craig Tiller | d7b68e7 | 2015-06-28 11:41:09 -0700 | [diff] [blame] | 49 | gpr_refcount refs; |
Craig Tiller | 7c0b4d7 | 2015-06-25 14:44:44 -0700 | [diff] [blame] | 50 | }; |
| 51 | |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 52 | struct grpc_lb_policy_vtable { |
Craig Tiller | d7b68e7 | 2015-06-28 11:41:09 -0700 | [diff] [blame] | 53 | void (*destroy)(grpc_lb_policy *policy); |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 54 | |
| 55 | void (*shutdown)(grpc_lb_policy *policy); |
| 56 | |
| 57 | /** implement grpc_lb_policy_pick */ |
| 58 | void (*pick)(grpc_lb_policy *policy, grpc_pollset *pollset, |
Craig Tiller | 7df28a7 | 2015-06-24 09:23:52 -0700 | [diff] [blame] | 59 | grpc_metadata_batch *initial_metadata, grpc_subchannel **target, |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 60 | grpc_iomgr_closure *on_complete); |
Craig Tiller | c7b5f76 | 2015-06-27 11:48:42 -0700 | [diff] [blame] | 61 | |
Craig Tiller | 48cb07c | 2015-07-15 16:16:15 -0700 | [diff] [blame] | 62 | /** try to enter a READY connectivity state */ |
| 63 | void (*exit_idle)(grpc_lb_policy *policy); |
| 64 | |
Craig Tiller | c7b5f76 | 2015-06-27 11:48:42 -0700 | [diff] [blame] | 65 | /** broadcast a transport op to all subchannels */ |
| 66 | void (*broadcast)(grpc_lb_policy *policy, grpc_transport_op *op); |
| 67 | |
| 68 | /** check the current connectivity of the lb_policy */ |
| 69 | grpc_connectivity_state (*check_connectivity)(grpc_lb_policy *policy); |
| 70 | |
| 71 | /** call notify when the connectivity state of a channel changes from *state. |
| 72 | Updates *state with the new state of the policy */ |
Craig Tiller | 4ab82d2 | 2015-06-29 09:40:33 -0700 | [diff] [blame] | 73 | void (*notify_on_state_change)(grpc_lb_policy *policy, |
| 74 | grpc_connectivity_state *state, |
| 75 | grpc_iomgr_closure *closure); |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 76 | }; |
| 77 | |
Craig Tiller | 1ada6ad | 2015-07-16 16:19:14 -0700 | [diff] [blame^] | 78 | #define GRPC_LB_POLICY_REFCOUNT_DEBUG |
| 79 | |
Craig Tiller | d7b68e7 | 2015-06-28 11:41:09 -0700 | [diff] [blame] | 80 | #ifdef GRPC_LB_POLICY_REFCOUNT_DEBUG |
Craig Tiller | 4ab82d2 | 2015-06-29 09:40:33 -0700 | [diff] [blame] | 81 | #define GRPC_LB_POLICY_REF(p, r) \ |
| 82 | grpc_lb_policy_ref((p), __FILE__, __LINE__, (r)) |
| 83 | #define GRPC_LB_POLICY_UNREF(p, r) \ |
| 84 | grpc_lb_policy_unref((p), __FILE__, __LINE__, (r)) |
| 85 | void grpc_lb_policy_ref(grpc_lb_policy *policy, const char *file, int line, |
| 86 | const char *reason); |
| 87 | void grpc_lb_policy_unref(grpc_lb_policy *policy, const char *file, int line, |
| 88 | const char *reason); |
Craig Tiller | d7b68e7 | 2015-06-28 11:41:09 -0700 | [diff] [blame] | 89 | #else |
| 90 | #define GRPC_LB_POLICY_REF(p, r) grpc_lb_policy_ref((p)) |
| 91 | #define GRPC_LB_POLICY_UNREF(p, r) grpc_lb_policy_unref((p)) |
Craig Tiller | f5f1712 | 2015-06-25 08:47:26 -0700 | [diff] [blame] | 92 | void grpc_lb_policy_ref(grpc_lb_policy *policy); |
| 93 | void grpc_lb_policy_unref(grpc_lb_policy *policy); |
Craig Tiller | d7b68e7 | 2015-06-28 11:41:09 -0700 | [diff] [blame] | 94 | #endif |
| 95 | |
| 96 | /** called by concrete implementations to initialize the base struct */ |
Craig Tiller | 4ab82d2 | 2015-06-29 09:40:33 -0700 | [diff] [blame] | 97 | void grpc_lb_policy_init(grpc_lb_policy *policy, |
| 98 | const grpc_lb_policy_vtable *vtable); |
Craig Tiller | f5f1712 | 2015-06-25 08:47:26 -0700 | [diff] [blame] | 99 | |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 100 | /** Start shutting down (fail any pending picks) */ |
| 101 | void grpc_lb_policy_shutdown(grpc_lb_policy *policy); |
| 102 | |
| 103 | /** Given initial metadata in \a initial_metadata, find an appropriate |
| 104 | target for this rpc, and 'return' it by calling \a on_complete after setting |
| 105 | \a target. |
| 106 | Picking can be asynchronous. Any IO should be done under \a pollset. */ |
| 107 | void grpc_lb_policy_pick(grpc_lb_policy *policy, grpc_pollset *pollset, |
| 108 | grpc_metadata_batch *initial_metadata, |
Craig Tiller | af69180 | 2015-06-23 14:57:07 -0700 | [diff] [blame] | 109 | grpc_subchannel **target, |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 110 | grpc_iomgr_closure *on_complete); |
| 111 | |
Craig Tiller | ca3e9d3 | 2015-06-27 18:37:27 -0700 | [diff] [blame] | 112 | void grpc_lb_policy_broadcast(grpc_lb_policy *policy, grpc_transport_op *op); |
| 113 | |
Craig Tiller | 48cb07c | 2015-07-15 16:16:15 -0700 | [diff] [blame] | 114 | void grpc_lb_policy_exit_idle(grpc_lb_policy *policy); |
| 115 | |
Craig Tiller | 1ada6ad | 2015-07-16 16:19:14 -0700 | [diff] [blame^] | 116 | void grpc_lb_policy_notify_on_state_change(grpc_lb_policy *policy, grpc_connectivity_state *state, |
| 117 | grpc_iomgr_closure *closure); |
| 118 | |
| 119 | grpc_connectivity_state grpc_lb_policy_check_connectivity(grpc_lb_policy *policy); |
| 120 | |
Craig Tiller | 9d0e047 | 2015-06-23 09:12:48 -0700 | [diff] [blame] | 121 | #endif /* GRPC_INTERNAL_CORE_CONFIG_LB_POLICY_H */ |