diff options
Diffstat (limited to 'src/core/ext/filters/client_channel/resolver_registry.c')
| -rw-r--r-- | src/core/ext/filters/client_channel/resolver_registry.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/src/core/ext/filters/client_channel/resolver_registry.c b/src/core/ext/filters/client_channel/resolver_registry.c new file mode 100644 index 0000000000..fa997bd68f --- /dev/null +++ b/src/core/ext/filters/client_channel/resolver_registry.c @@ -0,0 +1,174 @@ +/* + * + * 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 <string.h> + +#include <grpc/support/alloc.h> +#include <grpc/support/log.h> +#include <grpc/support/string_util.h> + +#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; +} |