1 /* 2 * 3 * Copyright 2015 gRPC authors. 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 * 17 */ 18 19 #ifndef GRPC_CORE_LIB_TRANSPORT_METADATA_BATCH_H 20 #define GRPC_CORE_LIB_TRANSPORT_METADATA_BATCH_H 21 22 #include <grpc/support/port_platform.h> 23 24 #include <stdbool.h> 25 26 #include <grpc/grpc.h> 27 #include <grpc/slice.h> 28 #include <grpc/support/time.h> 29 #include "src/core/lib/iomgr/exec_ctx.h" 30 #include "src/core/lib/transport/metadata.h" 31 #include "src/core/lib/transport/static_metadata.h" 32 33 typedef struct grpc_linked_mdelem { 34 grpc_mdelem md; 35 struct grpc_linked_mdelem* next; 36 struct grpc_linked_mdelem* prev; 37 void* reserved; 38 } grpc_linked_mdelem; 39 40 typedef struct grpc_mdelem_list { 41 size_t count; 42 size_t default_count; // Number of default keys. 43 grpc_linked_mdelem* head; 44 grpc_linked_mdelem* tail; 45 } grpc_mdelem_list; 46 47 typedef struct grpc_metadata_batch { 48 /** Metadata elements in this batch */ 49 grpc_mdelem_list list; 50 grpc_metadata_batch_callouts idx; 51 /** Used to calculate grpc-timeout at the point of sending, 52 or GRPC_MILLIS_INF_FUTURE if this batch does not need to send a 53 grpc-timeout */ 54 grpc_millis deadline; 55 } grpc_metadata_batch; 56 57 void grpc_metadata_batch_init(grpc_metadata_batch* batch); 58 void grpc_metadata_batch_destroy(grpc_metadata_batch* batch); 59 void grpc_metadata_batch_clear(grpc_metadata_batch* batch); 60 bool grpc_metadata_batch_is_empty(grpc_metadata_batch* batch); 61 62 /* Returns the transport size of the batch. */ 63 size_t grpc_metadata_batch_size(grpc_metadata_batch* batch); 64 65 /** Remove \a storage from the batch, unreffing the mdelem contained */ 66 void grpc_metadata_batch_remove(grpc_metadata_batch* batch, 67 grpc_linked_mdelem* storage); 68 69 /** Substitute a new mdelem for an old value */ 70 grpc_error* grpc_metadata_batch_substitute(grpc_metadata_batch* batch, 71 grpc_linked_mdelem* storage, 72 grpc_mdelem new_value); 73 74 void grpc_metadata_batch_set_value(grpc_linked_mdelem* storage, 75 grpc_slice value); 76 77 /** Add \a storage to the beginning of \a batch. storage->md is 78 assumed to be valid. 79 \a storage is owned by the caller and must survive for the 80 lifetime of batch. This usually means it should be around 81 for the lifetime of the call. */ 82 grpc_error* grpc_metadata_batch_link_head(grpc_metadata_batch* batch, 83 grpc_linked_mdelem* storage) 84 GRPC_MUST_USE_RESULT; 85 86 /** Add \a storage to the end of \a batch. storage->md is 87 assumed to be valid. 88 \a storage is owned by the caller and must survive for the 89 lifetime of batch. This usually means it should be around 90 for the lifetime of the call. */ 91 grpc_error* grpc_metadata_batch_link_tail(grpc_metadata_batch* batch, 92 grpc_linked_mdelem* storage) 93 GRPC_MUST_USE_RESULT; 94 95 /** Add \a elem_to_add as the first element in \a batch, using 96 \a storage as backing storage for the linked list element. 97 \a storage is owned by the caller and must survive for the 98 lifetime of batch. This usually means it should be around 99 for the lifetime of the call. 100 Takes ownership of \a elem_to_add */ 101 grpc_error* grpc_metadata_batch_add_head( 102 grpc_metadata_batch* batch, grpc_linked_mdelem* storage, 103 grpc_mdelem elem_to_add) GRPC_MUST_USE_RESULT; 104 105 /** Add \a elem_to_add as the last element in \a batch, using 106 \a storage as backing storage for the linked list element. 107 \a storage is owned by the caller and must survive for the 108 lifetime of batch. This usually means it should be around 109 for the lifetime of the call. 110 Takes ownership of \a elem_to_add */ 111 grpc_error* grpc_metadata_batch_add_tail( 112 grpc_metadata_batch* batch, grpc_linked_mdelem* storage, 113 grpc_mdelem elem_to_add) GRPC_MUST_USE_RESULT; 114 115 grpc_error* grpc_attach_md_to_error(grpc_error* src, grpc_mdelem md); 116 117 typedef struct { 118 grpc_error* error; 119 grpc_mdelem md; 120 } grpc_filtered_mdelem; 121 122 #define GRPC_FILTERED_ERROR(error) \ 123 { (error), GRPC_MDNULL } 124 #define GRPC_FILTERED_MDELEM(md) \ 125 { GRPC_ERROR_NONE, (md) } 126 #define GRPC_FILTERED_REMOVE() \ 127 { GRPC_ERROR_NONE, GRPC_MDNULL } 128 129 typedef grpc_filtered_mdelem (*grpc_metadata_batch_filter_func)( 130 void* user_data, grpc_mdelem elem); 131 grpc_error* grpc_metadata_batch_filter( 132 grpc_metadata_batch* batch, grpc_metadata_batch_filter_func func, 133 void* user_data, const char* composite_error_string) GRPC_MUST_USE_RESULT; 134 135 #ifndef NDEBUG 136 void grpc_metadata_batch_assert_ok(grpc_metadata_batch* comd); 137 #else 138 #define grpc_metadata_batch_assert_ok(comd) \ 139 do { \ 140 } while (0) 141 #endif 142 143 /// Copies \a src to \a dst. \a storage must point to an array of 144 /// \a grpc_linked_mdelem structs of at least the same size as \a src. 145 void grpc_metadata_batch_copy(grpc_metadata_batch* src, 146 grpc_metadata_batch* dst, 147 grpc_linked_mdelem* storage); 148 149 void grpc_metadata_batch_move(grpc_metadata_batch* src, 150 grpc_metadata_batch* dst); 151 152 #endif /* GRPC_CORE_LIB_TRANSPORT_METADATA_BATCH_H */ 153
