Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 1 | /* |
| 2 | * |
Craig Tiller | 0605995 | 2015-02-18 08:34:56 -0800 | [diff] [blame] | 3 | * Copyright 2015, Google Inc. |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 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 | |
Nicolas "Pixel" Noble | 1ff52d5 | 2015-03-01 05:24:36 +0100 | [diff] [blame] | 34 | #ifndef GRPC_INTERNAL_CORE_CHANNEL_CHANNEL_STACK_H |
| 35 | #define GRPC_INTERNAL_CORE_CHANNEL_CHANNEL_STACK_H |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 36 | |
| 37 | /* A channel filter defines how operations on a channel are implemented. |
| 38 | Channel filters are chained together to create full channels, and if those |
| 39 | chains are linear, then channel stacks provide a mechanism to minimize |
| 40 | allocations for that chain. |
| 41 | Call stacks are created by channel stacks and represent the per-call data |
| 42 | for that stack. */ |
| 43 | |
| 44 | #include <stddef.h> |
| 45 | |
| 46 | #include <grpc/grpc.h> |
| 47 | #include <grpc/support/log.h> |
Craig Tiller | 6e7c622 | 2015-02-20 15:31:21 -0800 | [diff] [blame] | 48 | #include "src/core/debug/trace.h" |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 49 | #include "src/core/transport/transport.h" |
| 50 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 51 | typedef struct grpc_channel_element grpc_channel_element; |
| 52 | typedef struct grpc_call_element grpc_call_element; |
| 53 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 54 | /* Channel filters specify: |
| 55 | 1. the amount of memory needed in the channel & call (via the sizeof_XXX |
| 56 | members) |
| 57 | 2. functions to initialize and destroy channel & call data |
| 58 | (init_XXX, destroy_XXX) |
| 59 | 3. functions to implement call operations and channel operations (call_op, |
| 60 | channel_op) |
| 61 | 4. a name, which is useful when debugging |
| 62 | |
| 63 | Members are laid out in approximate frequency of use order. */ |
| 64 | typedef struct { |
| 65 | /* Called to eg. send/receive data on a call. |
| 66 | See grpc_call_next_op on how to call the next element in the stack */ |
Craig Tiller | 3f47542 | 2015-06-25 10:43:05 -0700 | [diff] [blame] | 67 | void (*start_transport_stream_op)(grpc_call_element *elem, |
Craig Tiller | 079a11b | 2015-06-30 10:07:15 -0700 | [diff] [blame] | 68 | grpc_transport_stream_op *op); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 69 | /* Called to handle channel level operations - e.g. new calls, or transport |
| 70 | closure. |
| 71 | See grpc_channel_next_op on how to call the next element in the stack */ |
Craig Tiller | 3f47542 | 2015-06-25 10:43:05 -0700 | [diff] [blame] | 72 | void (*start_transport_op)(grpc_channel_element *elem, grpc_transport_op *op); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 73 | |
| 74 | /* sizeof(per call data) */ |
| 75 | size_t sizeof_call_data; |
| 76 | /* Initialize per call data. |
| 77 | elem is initialized at the start of the call, and elem->call_data is what |
| 78 | needs initializing. |
| 79 | The filter does not need to do any chaining. |
| 80 | server_transport_data is an opaque pointer. If it is NULL, this call is |
| 81 | on a client; if it is non-NULL, then it points to memory owned by the |
| 82 | transport and is on the server. Most filters want to ignore this |
| 83 | argument.*/ |
| 84 | void (*init_call_elem)(grpc_call_element *elem, |
Craig Tiller | 3f2c221 | 2015-04-23 07:56:33 -0700 | [diff] [blame] | 85 | const void *server_transport_data, |
Craig Tiller | b7959a0 | 2015-06-25 08:50:54 -0700 | [diff] [blame] | 86 | grpc_transport_stream_op *initial_op); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 87 | /* Destroy per call data. |
| 88 | The filter does not need to do any chaining */ |
| 89 | void (*destroy_call_elem)(grpc_call_element *elem); |
| 90 | |
| 91 | /* sizeof(per channel data) */ |
| 92 | size_t sizeof_channel_data; |
| 93 | /* Initialize per-channel data. |
| 94 | elem is initialized at the start of the call, and elem->channel_data is |
| 95 | what needs initializing. |
| 96 | is_first, is_last designate this elements position in the stack, and are |
| 97 | useful for asserting correct configuration by upper layer code. |
| 98 | The filter does not need to do any chaining */ |
Craig Tiller | 079a11b | 2015-06-30 10:07:15 -0700 | [diff] [blame] | 99 | void (*init_channel_elem)(grpc_channel_element *elem, grpc_channel *master, |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 100 | const grpc_channel_args *args, |
| 101 | grpc_mdctx *metadata_context, int is_first, |
| 102 | int is_last); |
| 103 | /* Destroy per channel data. |
| 104 | The filter does not need to do any chaining */ |
| 105 | void (*destroy_channel_elem)(grpc_channel_element *elem); |
| 106 | |
Craig Tiller | 1b22b9d | 2015-07-20 13:42:22 -0700 | [diff] [blame] | 107 | /* Implement grpc_call_get_peer() */ |
| 108 | char *(*get_peer)(grpc_call_element *elem); |
| 109 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 110 | /* The name of this filter */ |
| 111 | const char *name; |
| 112 | } grpc_channel_filter; |
| 113 | |
| 114 | /* A channel_element tracks its filter and the filter requested memory within |
| 115 | a channel allocation */ |
| 116 | struct grpc_channel_element { |
| 117 | const grpc_channel_filter *filter; |
| 118 | void *channel_data; |
| 119 | }; |
| 120 | |
| 121 | /* A call_element tracks its filter, the filter requested memory within |
| 122 | a channel allocation, and the filter requested memory within a call |
| 123 | allocation */ |
| 124 | struct grpc_call_element { |
| 125 | const grpc_channel_filter *filter; |
| 126 | void *channel_data; |
| 127 | void *call_data; |
| 128 | }; |
| 129 | |
| 130 | /* A channel stack tracks a set of related filters for one channel, and |
| 131 | guarantees they live within a single malloc() allocation */ |
| 132 | typedef struct { |
| 133 | size_t count; |
| 134 | /* Memory required for a call stack (computed at channel stack |
| 135 | initialization) */ |
| 136 | size_t call_stack_size; |
| 137 | } grpc_channel_stack; |
| 138 | |
| 139 | /* A call stack tracks a set of related filters for one call, and guarantees |
| 140 | they live within a single malloc() allocation */ |
Craig Tiller | 6e7c622 | 2015-02-20 15:31:21 -0800 | [diff] [blame] | 141 | typedef struct { size_t count; } grpc_call_stack; |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 142 | |
| 143 | /* Get a channel element given a channel stack and its index */ |
| 144 | grpc_channel_element *grpc_channel_stack_element(grpc_channel_stack *stack, |
| 145 | size_t i); |
| 146 | /* Get the last channel element in a channel stack */ |
| 147 | grpc_channel_element *grpc_channel_stack_last_element( |
| 148 | grpc_channel_stack *stack); |
| 149 | /* Get a call stack element given a call stack and an index */ |
| 150 | grpc_call_element *grpc_call_stack_element(grpc_call_stack *stack, size_t i); |
| 151 | |
| 152 | /* Determine memory required for a channel stack containing a set of filters */ |
| 153 | size_t grpc_channel_stack_size(const grpc_channel_filter **filters, |
| 154 | size_t filter_count); |
| 155 | /* Initialize a channel stack given some filters */ |
| 156 | void grpc_channel_stack_init(const grpc_channel_filter **filters, |
Craig Tiller | 079a11b | 2015-06-30 10:07:15 -0700 | [diff] [blame] | 157 | size_t filter_count, grpc_channel *master, |
| 158 | const grpc_channel_args *args, |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 159 | grpc_mdctx *metadata_context, |
| 160 | grpc_channel_stack *stack); |
| 161 | /* Destroy a channel stack */ |
| 162 | void grpc_channel_stack_destroy(grpc_channel_stack *stack); |
| 163 | |
| 164 | /* Initialize a call stack given a channel stack. transport_server_data is |
| 165 | expected to be NULL on a client, or an opaque transport owned pointer on the |
| 166 | server. */ |
| 167 | void grpc_call_stack_init(grpc_channel_stack *channel_stack, |
| 168 | const void *transport_server_data, |
Craig Tiller | b7959a0 | 2015-06-25 08:50:54 -0700 | [diff] [blame] | 169 | grpc_transport_stream_op *initial_op, |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 170 | grpc_call_stack *call_stack); |
| 171 | /* Destroy a call stack */ |
| 172 | void grpc_call_stack_destroy(grpc_call_stack *stack); |
| 173 | |
Craig Tiller | 83f88d9 | 2015-04-21 16:02:05 -0700 | [diff] [blame] | 174 | /* Call the next operation in a call stack */ |
Craig Tiller | b7959a0 | 2015-06-25 08:50:54 -0700 | [diff] [blame] | 175 | void grpc_call_next_op(grpc_call_element *elem, grpc_transport_stream_op *op); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 176 | /* Call the next operation (depending on call directionality) in a channel |
| 177 | stack */ |
Craig Tiller | 3f47542 | 2015-06-25 10:43:05 -0700 | [diff] [blame] | 178 | void grpc_channel_next_op(grpc_channel_element *elem, grpc_transport_op *op); |
Craig Tiller | 1b22b9d | 2015-07-20 13:42:22 -0700 | [diff] [blame] | 179 | /* Pass through a request to get_peer to the next child element */ |
| 180 | char *grpc_call_next_get_peer(grpc_call_element *elem); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 181 | |
| 182 | /* Given the top element of a channel stack, get the channel stack itself */ |
| 183 | grpc_channel_stack *grpc_channel_stack_from_top_element( |
| 184 | grpc_channel_element *elem); |
| 185 | /* Given the top element of a call stack, get the call stack itself */ |
| 186 | grpc_call_stack *grpc_call_stack_from_top_element(grpc_call_element *elem); |
| 187 | |
| 188 | void grpc_call_log_op(char *file, int line, gpr_log_severity severity, |
Craig Tiller | b7959a0 | 2015-06-25 08:50:54 -0700 | [diff] [blame] | 189 | grpc_call_element *elem, grpc_transport_stream_op *op); |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 190 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 191 | void grpc_call_element_send_cancel(grpc_call_element *cur_elem); |
| 192 | |
Craig Tiller | faa8480 | 2015-03-01 21:56:38 -0800 | [diff] [blame] | 193 | extern int grpc_trace_channel; |
| 194 | |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 195 | #define GRPC_CALL_LOG_OP(sev, elem, op) \ |
Craig Tiller | faa8480 | 2015-03-01 21:56:38 -0800 | [diff] [blame] | 196 | if (grpc_trace_channel) grpc_call_log_op(sev, elem, op) |
Nicolas Noble | b7ebd3b | 2014-11-26 16:33:03 -0800 | [diff] [blame] | 197 | |
Craig Tiller | 87d5b19 | 2015-04-16 14:37:57 -0700 | [diff] [blame] | 198 | #endif /* GRPC_INTERNAL_CORE_CHANNEL_CHANNEL_STACK_H */ |