third_party/grpc/src/core/client_config/lb_policy_registry.c

/*
 *
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#include "src/core/client_config/lb_policy_registry.h"

#include <string.h>

#define MAX_POLICIES 10

static grpc_lb_policy_factory *g_all_of_the_lb_policies[MAX_POLICIES];
static int g_number_of_lb_policies = 0;

static grpc_lb_policy_factory *g_default_lb_policy_factory;

void grpc_lb_policy_registry_init(grpc_lb_policy_factory *default_factory) {
  g_number_of_lb_policies = 0;
  g_default_lb_policy_factory = default_factory;
}

void grpc_lb_policy_registry_shutdown(void) {
  int i;
  for (i = 0; i < g_number_of_lb_policies; i++) {
    grpc_lb_policy_factory_unref(g_all_of_the_lb_policies[i]);
  }
}

void grpc_register_lb_policy(grpc_lb_policy_factory *factory) {
  int i;
  for (i = 0; i < g_number_of_lb_policies; i++) {
    GPR_ASSERT(0 != strcmp(factory->vtable->name,
                           g_all_of_the_lb_policies[i]->vtable->name));
  }
  GPR_ASSERT(g_number_of_lb_policies != MAX_POLICIES);
  grpc_lb_policy_factory_ref(factory);
  g_all_of_the_lb_policies[g_number_of_lb_policies++] = factory;
}

static grpc_lb_policy_factory *lookup_factory(const char *name) {
  int i;

  if (name == NULL) return NULL;

  for (i = 0; i < g_number_of_lb_policies; i++) {
    if (0 == strcmp(name, g_all_of_the_lb_policies[i]->vtable->name)) {
      return g_all_of_the_lb_policies[i];
    }
  }

  return NULL;
}

grpc_lb_policy *grpc_lb_policy_create(const char *name,
                                      grpc_lb_policy_args *args) {
  grpc_lb_policy_factory *factory = lookup_factory(name);
  grpc_lb_policy *lb_policy =
      grpc_lb_policy_factory_create_lb_policy(factory, args);
  return lb_policy;
}