3 * Copyright 2015 gRPC authors.
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
9 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 #ifndef GRPC_CORE_LIB_CHANNEL_CHANNEL_ARGS_H
20 #define GRPC_CORE_LIB_CHANNEL_CHANNEL_ARGS_H
22 #include <grpc/support/port_platform.h>
24 #include <grpc/grpc.h>
26 // Channel args are intentionally immutable, to avoid the need for locking.
28 /** Copy the arguments in \a src into a new instance */
29 grpc_channel_args* grpc_channel_args_copy(const grpc_channel_args* src);
31 /** Copy the arguments in \a src into a new instance, stably sorting keys */
32 grpc_channel_args* grpc_channel_args_normalize(const grpc_channel_args* src);
34 /** Copy the arguments in \a src and append \a to_add. If \a to_add is NULL, it
35 * is equivalent to calling \a grpc_channel_args_copy. */
36 grpc_channel_args* grpc_channel_args_copy_and_add(const grpc_channel_args* src,
37 const grpc_arg* to_add,
40 /** Copies the arguments in \a src except for those whose keys are in
42 grpc_channel_args* grpc_channel_args_copy_and_remove(
43 const grpc_channel_args* src, const char** to_remove, size_t num_to_remove);
45 /** Copies the arguments from \a src except for those whose keys are in
46 \a to_remove and appends the arguments in \a to_add. */
47 grpc_channel_args* grpc_channel_args_copy_and_add_and_remove(
48 const grpc_channel_args* src, const char** to_remove, size_t num_to_remove,
49 const grpc_arg* to_add, size_t num_to_add);
51 /** Perform the union of \a a and \a b, prioritizing \a a entries */
52 grpc_channel_args* grpc_channel_args_union(const grpc_channel_args* a,
53 const grpc_channel_args* b);
55 /** Destroy arguments created by \a grpc_channel_args_copy */
56 void grpc_channel_args_destroy(grpc_channel_args* a);
57 inline void grpc_channel_args_destroy(const grpc_channel_args* a) {
58 grpc_channel_args_destroy(const_cast<grpc_channel_args*>(a));
61 int grpc_channel_args_compare(const grpc_channel_args* a,
62 const grpc_channel_args* b);
64 /** Returns the value of argument \a name from \a args, or NULL if not found. */
65 const grpc_arg* grpc_channel_args_find(const grpc_channel_args* args,
68 bool grpc_channel_args_want_minimal_stack(const grpc_channel_args* args);
70 typedef struct grpc_integer_options {
71 int default_value; // Return this if value is outside of expected bounds.
74 } grpc_integer_options;
76 /** Returns the value of \a arg, subject to the constraints in \a options. */
77 int grpc_channel_arg_get_integer(const grpc_arg* arg,
78 const grpc_integer_options options);
79 /** Similar to the above, but needs to find the arg from \a args by the name
81 int grpc_channel_args_find_integer(const grpc_channel_args* args,
83 const grpc_integer_options options);
85 /** Returns the value of \a arg if \a arg is of type GRPC_ARG_STRING.
86 Otherwise, emits a warning log, and returns nullptr.
87 If arg is nullptr, returns nullptr, and does not emit a warning. */
88 char* grpc_channel_arg_get_string(const grpc_arg* arg);
89 /** Similar to the above, but needs to find the arg from \a args by the name
91 char* grpc_channel_args_find_string(const grpc_channel_args* args,
93 /** If \a arg is of type GRPC_ARG_INTEGER, returns true if it's non-zero.
94 * Returns \a default_value if \a arg is of other types. */
95 bool grpc_channel_arg_get_bool(const grpc_arg* arg, bool default_value);
96 /** Similar to the above, but needs to find the arg from \a args by the name
98 bool grpc_channel_args_find_bool(const grpc_channel_args* args,
99 const char* name, bool default_value);
101 // Helpers for creating channel args.
102 grpc_arg grpc_channel_arg_string_create(char* name, char* value);
103 grpc_arg grpc_channel_arg_integer_create(char* name, int value);
104 grpc_arg grpc_channel_arg_pointer_create(char* name, void* value,
105 const grpc_arg_pointer_vtable* vtable);
107 // Returns a string representing channel args in human-readable form.
108 // Callers takes ownership of result.
109 char* grpc_channel_args_string(const grpc_channel_args* args);
111 #endif /* GRPC_CORE_LIB_CHANNEL_CHANNEL_ARGS_H */