/* * * Copyright 2015, Google Inc. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following disclaimer * in the documentation and/or other materials provided with the * distribution. * * Neither the name of Google Inc. nor the names of its * contributors may be used to endorse or promote products derived from * this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * */ #include "src/core/ext/filters/client_channel/resolver_registry.h" #include #include #include #include #define MAX_RESOLVERS 10 #define DEFAULT_RESOLVER_PREFIX_MAX_LENGTH 32 static grpc_resolver_factory *g_all_of_the_resolvers[MAX_RESOLVERS]; static int g_number_of_resolvers = 0; static char g_default_resolver_prefix[DEFAULT_RESOLVER_PREFIX_MAX_LENGTH] = "dns:///"; void grpc_resolver_registry_init() {} void grpc_resolver_registry_shutdown(void) { for (int i = 0; i < g_number_of_resolvers; i++) { grpc_resolver_factory_unref(g_all_of_the_resolvers[i]); } // FIXME(ctiller): this should live in grpc_resolver_registry_init, // however that would have the client_channel plugin call this AFTER we start // registering resolvers from third party plugins, and so they'd never show // up. // We likely need some kind of dependency system for plugins.... what form // that takes is TBD. g_number_of_resolvers = 0; } void grpc_resolver_registry_set_default_prefix( const char *default_resolver_prefix) { const size_t len = strlen(default_resolver_prefix); GPR_ASSERT(len < DEFAULT_RESOLVER_PREFIX_MAX_LENGTH && "default resolver prefix too long"); GPR_ASSERT(len > 0 && "default resolver prefix can't be empty"); // By the previous assert, default_resolver_prefix is safe to be copied with a // plain strcpy. strcpy(g_default_resolver_prefix, default_resolver_prefix); } void grpc_register_resolver_type(grpc_resolver_factory *factory) { int i; for (i = 0; i < g_number_of_resolvers; i++) { GPR_ASSERT(0 != strcmp(factory->vtable->scheme, g_all_of_the_resolvers[i]->vtable->scheme)); } GPR_ASSERT(g_number_of_resolvers != MAX_RESOLVERS); grpc_resolver_factory_ref(factory); g_all_of_the_resolvers[g_number_of_resolvers++] = factory; } static grpc_resolver_factory *lookup_factory(const char *name) { int i; for (i = 0; i < g_number_of_resolvers; i++) { if (0 == strcmp(name, g_all_of_the_resolvers[i]->vtable->scheme)) { return g_all_of_the_resolvers[i]; } } return NULL; } grpc_resolver_factory *grpc_resolver_factory_lookup(const char *name) { grpc_resolver_factory *f = lookup_factory(name); if (f) grpc_resolver_factory_ref(f); return f; } static grpc_resolver_factory *lookup_factory_by_uri(grpc_uri *uri) { if (!uri) return NULL; return lookup_factory(uri->scheme); } static grpc_resolver_factory *resolve_factory(grpc_exec_ctx *exec_ctx, const char *target, grpc_uri **uri, char **canonical_target) { grpc_resolver_factory *factory = NULL; GPR_ASSERT(uri != NULL); *uri = grpc_uri_parse(exec_ctx, target, 1); factory = lookup_factory_by_uri(*uri); if (factory == NULL) { grpc_uri_destroy(*uri); gpr_asprintf(canonical_target, "%s%s", g_default_resolver_prefix, target); *uri = grpc_uri_parse(exec_ctx, *canonical_target, 1); factory = lookup_factory_by_uri(*uri); if (factory == NULL) { grpc_uri_destroy(grpc_uri_parse(exec_ctx, target, 0)); grpc_uri_destroy(grpc_uri_parse(exec_ctx, *canonical_target, 0)); gpr_log(GPR_ERROR, "don't know how to resolve '%s' or '%s'", target, *canonical_target); } } return factory; } grpc_resolver *grpc_resolver_create(grpc_exec_ctx *exec_ctx, const char *target, const grpc_channel_args *args, grpc_pollset_set *pollset_set, grpc_combiner *combiner) { grpc_uri *uri = NULL; char *canonical_target = NULL; grpc_resolver_factory *factory = resolve_factory(exec_ctx, target, &uri, &canonical_target); grpc_resolver *resolver; grpc_resolver_args resolver_args; memset(&resolver_args, 0, sizeof(resolver_args)); resolver_args.uri = uri; resolver_args.args = args; resolver_args.pollset_set = pollset_set; resolver_args.combiner = combiner; resolver = grpc_resolver_factory_create_resolver(exec_ctx, factory, &resolver_args); grpc_uri_destroy(uri); gpr_free(canonical_target); return resolver; } char *grpc_get_default_authority(grpc_exec_ctx *exec_ctx, const char *target) { grpc_uri *uri = NULL; char *canonical_target = NULL; grpc_resolver_factory *factory = resolve_factory(exec_ctx, target, &uri, &canonical_target); char *authority = grpc_resolver_factory_get_default_authority(factory, uri); grpc_uri_destroy(uri); gpr_free(canonical_target); return authority; } char *grpc_resolver_factory_add_default_prefix_if_needed( grpc_exec_ctx *exec_ctx, const char *target) { grpc_uri *uri = NULL; char *canonical_target = NULL; resolve_factory(exec_ctx, target, &uri, &canonical_target); grpc_uri_destroy(uri); return canonical_target == NULL ? gpr_strdup(target) : canonical_target; }