• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  *
3  * Copyright 2016 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 #include <grpc/support/port_platform.h>
20 
21 #include "src/core/lib/surface/channel_init.h"
22 
23 #include <grpc/support/alloc.h>
24 
25 typedef struct stage_slot {
26   grpc_channel_init_stage fn;
27   void* arg;
28   int priority;
29   size_t insertion_order;
30 } stage_slot;
31 
32 typedef struct stage_slots {
33   stage_slot* slots;
34   size_t num_slots;
35   size_t cap_slots;
36 } stage_slots;
37 
38 static stage_slots g_slots[GRPC_NUM_CHANNEL_STACK_TYPES];
39 static bool g_finalized;
40 
grpc_channel_init_init(void)41 void grpc_channel_init_init(void) {
42   for (int i = 0; i < GRPC_NUM_CHANNEL_STACK_TYPES; i++) {
43     g_slots[i].slots = nullptr;
44     g_slots[i].num_slots = 0;
45     g_slots[i].cap_slots = 0;
46   }
47   g_finalized = false;
48 }
49 
grpc_channel_init_register_stage(grpc_channel_stack_type type,int priority,grpc_channel_init_stage stage,void * stage_arg)50 void grpc_channel_init_register_stage(grpc_channel_stack_type type,
51                                       int priority,
52                                       grpc_channel_init_stage stage,
53                                       void* stage_arg) {
54   GPR_ASSERT(!g_finalized);
55   if (g_slots[type].cap_slots == g_slots[type].num_slots) {
56     g_slots[type].cap_slots = GPR_MAX(8, 3 * g_slots[type].cap_slots / 2);
57     g_slots[type].slots = static_cast<stage_slot*>(
58         gpr_realloc(g_slots[type].slots,
59                     g_slots[type].cap_slots * sizeof(*g_slots[type].slots)));
60   }
61   stage_slot* s = &g_slots[type].slots[g_slots[type].num_slots++];
62   s->insertion_order = g_slots[type].num_slots;
63   s->priority = priority;
64   s->fn = stage;
65   s->arg = stage_arg;
66 }
67 
compare_slots(const void * a,const void * b)68 static int compare_slots(const void* a, const void* b) {
69   const stage_slot* sa = static_cast<const stage_slot*>(a);
70   const stage_slot* sb = static_cast<const stage_slot*>(b);
71 
72   int c = GPR_ICMP(sa->priority, sb->priority);
73   if (c != 0) return c;
74   return GPR_ICMP(sa->insertion_order, sb->insertion_order);
75 }
76 
grpc_channel_init_finalize(void)77 void grpc_channel_init_finalize(void) {
78   GPR_ASSERT(!g_finalized);
79   for (int i = 0; i < GRPC_NUM_CHANNEL_STACK_TYPES; i++) {
80     qsort(g_slots[i].slots, g_slots[i].num_slots, sizeof(*g_slots[i].slots),
81           compare_slots);
82   }
83   g_finalized = true;
84 }
85 
grpc_channel_init_shutdown(void)86 void grpc_channel_init_shutdown(void) {
87   for (int i = 0; i < GRPC_NUM_CHANNEL_STACK_TYPES; i++) {
88     gpr_free(g_slots[i].slots);
89     g_slots[i].slots =
90         static_cast<stage_slot*>((void*)static_cast<uintptr_t>(0xdeadbeef));
91   }
92 }
93 
grpc_channel_init_create_stack(grpc_channel_stack_builder * builder,grpc_channel_stack_type type)94 bool grpc_channel_init_create_stack(grpc_channel_stack_builder* builder,
95                                     grpc_channel_stack_type type) {
96   GPR_ASSERT(g_finalized);
97 
98   grpc_channel_stack_builder_set_name(builder,
99                                       grpc_channel_stack_type_string(type));
100 
101   for (size_t i = 0; i < g_slots[type].num_slots; i++) {
102     const stage_slot* slot = &g_slots[type].slots[i];
103     if (!slot->fn(builder, slot->arg)) {
104       return false;
105     }
106   }
107 
108   return true;
109 }
110