src/core/ext/filters/client_channel/resolver/sockaddr/sockaddr_resolver.cc - third_party/grpc - Git at Google

 /*
  *
  * Copyright 2015-2016 gRPC authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  */

 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>

 #include <grpc/support/alloc.h>
 #include <grpc/support/host_port.h>
 #include <grpc/support/port_platform.h>
 #include <grpc/support/string_util.h>

 #include "src/core/ext/filters/client_channel/lb_policy_factory.h"
 #include "src/core/ext/filters/client_channel/parse_address.h"
 #include "src/core/ext/filters/client_channel/resolver_registry.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/gpr/string.h"
 #include "src/core/lib/iomgr/combiner.h"
 #include "src/core/lib/iomgr/resolve_address.h"
 #include "src/core/lib/iomgr/unix_sockets_posix.h"
 #include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"

 typedef struct {
   /** base class: must be first */
   grpc_resolver base;
   /** the addresses that we've 'resolved' */
   grpc_lb_addresses* addresses;
   /** channel args */
   grpc_channel_args* channel_args;
   /** have we published? */
   bool published;
   /** pending next completion, or NULL */
   grpc_closure* next_completion;
   /** target result address for next completion */
   grpc_channel_args** target_result;
 } sockaddr_resolver;

 static void sockaddr_destroy(grpc_resolver* r);

 static void sockaddr_maybe_finish_next_locked(sockaddr_resolver* r);

 static void sockaddr_shutdown_locked(grpc_resolver* r);
 static void sockaddr_channel_saw_error_locked(grpc_resolver* r);
 static void sockaddr_next_locked(grpc_resolver* r,
                                  grpc_channel_args** target_result,
                                  grpc_closure* on_complete);

 static const grpc_resolver_vtable sockaddr_resolver_vtable = {
     sockaddr_destroy, sockaddr_shutdown_locked,
     sockaddr_channel_saw_error_locked, sockaddr_next_locked};

 static void sockaddr_shutdown_locked(grpc_resolver* resolver) {
   sockaddr_resolver* r = (sockaddr_resolver*)resolver;
   if (r->next_completion != nullptr) {
     *r->target_result = nullptr;
     GRPC_CLOSURE_SCHED(r->next_completion, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                                                "Resolver Shutdown"));
     r->next_completion = nullptr;
   }
 }

 static void sockaddr_channel_saw_error_locked(grpc_resolver* resolver) {
   sockaddr_resolver* r = (sockaddr_resolver*)resolver;
   r->published = false;
   sockaddr_maybe_finish_next_locked(r);
 }

 static void sockaddr_next_locked(grpc_resolver* resolver,
                                  grpc_channel_args** target_result,
                                  grpc_closure* on_complete) {
   sockaddr_resolver* r = (sockaddr_resolver*)resolver;
   GPR_ASSERT(!r->next_completion);
   r->next_completion = on_complete;
   r->target_result = target_result;
   sockaddr_maybe_finish_next_locked(r);
 }

 static void sockaddr_maybe_finish_next_locked(sockaddr_resolver* r) {
   if (r->next_completion != nullptr && !r->published) {
     r->published = true;
     grpc_arg arg = grpc_lb_addresses_create_channel_arg(r->addresses);
     *r->target_result =
         grpc_channel_args_copy_and_add(r->channel_args, &arg, 1);
     GRPC_CLOSURE_SCHED(r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = nullptr;
   }
 }

 static void sockaddr_destroy(grpc_resolver* gr) {
   sockaddr_resolver* r = (sockaddr_resolver*)gr;
   grpc_lb_addresses_destroy(r->addresses);
   grpc_channel_args_destroy(r->channel_args);
   gpr_free(r);
 }

 static char* ip_get_default_authority(grpc_uri* uri) {
   const char* path = uri->path;
   if (path[0] == '/') ++path;
   return gpr_strdup(path);
 }

 static char* ipv4_get_default_authority(grpc_resolver_factory* factory,
                                         grpc_uri* uri) {
   return ip_get_default_authority(uri);
 }

 static char* ipv6_get_default_authority(grpc_resolver_factory* factory,
                                         grpc_uri* uri) {
   return ip_get_default_authority(uri);
 }

 #ifdef GRPC_HAVE_UNIX_SOCKET
 char* unix_get_default_authority(grpc_resolver_factory* factory,
                                  grpc_uri* uri) {
   return gpr_strdup("localhost");
 }
 #endif

 static void do_nothing(void* ignored) {}

 static grpc_resolver* sockaddr_create(grpc_resolver_args* args,
                                       bool parse(const grpc_uri* uri,
                                                  grpc_resolved_address* dst)) {
   if (0 != strcmp(args->uri->authority, "")) {
     gpr_log(GPR_ERROR, "authority based uri's not supported by the %s scheme",
             args->uri->scheme);
     return nullptr;
   }
   /* Construct addresses. */
   grpc_slice path_slice =
       grpc_slice_new(args->uri->path, strlen(args->uri->path), do_nothing);
   grpc_slice_buffer path_parts;
   grpc_slice_buffer_init(&path_parts);
   grpc_slice_split(path_slice, ",", &path_parts);
   grpc_lb_addresses* addresses = grpc_lb_addresses_create(
       path_parts.count, nullptr /* user_data_vtable */);
   bool errors_found = false;
   for (size_t i = 0; i < addresses->num_addresses; i++) {
     grpc_uri ith_uri = *args->uri;
     char* part_str = grpc_slice_to_c_string(path_parts.slices[i]);
     ith_uri.path = part_str;
     if (!parse(&ith_uri, &addresses->addresses[i].address)) {
       errors_found = true; /* GPR_TRUE */
     }
     gpr_free(part_str);
     if (errors_found) break;
   }
   grpc_slice_buffer_destroy_internal(&path_parts);
   grpc_slice_unref_internal(path_slice);
   if (errors_found) {
     grpc_lb_addresses_destroy(addresses);
     return nullptr;
   }
   /* Instantiate resolver. */
   sockaddr_resolver* r =
       (sockaddr_resolver*)gpr_zalloc(sizeof(sockaddr_resolver));
   r->addresses = addresses;
   r->channel_args = grpc_channel_args_copy(args->args);
   grpc_resolver_init(&r->base, &sockaddr_resolver_vtable, args->combiner);
   return &r->base;
 }

 /*
  * FACTORY
  */

 static void sockaddr_factory_ref(grpc_resolver_factory* factory) {}

 static void sockaddr_factory_unref(grpc_resolver_factory* factory) {}

 #define DECL_FACTORY(name)                                                  \
   static grpc_resolver* name##_factory_create_resolver(                     \
       grpc_resolver_factory* factory, grpc_resolver_args* args) {           \
     return sockaddr_create(args, grpc_parse_##name);                        \
   }                                                                         \
   static const grpc_resolver_factory_vtable name##_factory_vtable = {       \
       sockaddr_factory_ref, sockaddr_factory_unref,                         \
       name##_factory_create_resolver, name##_get_default_authority, #name}; \
   static grpc_resolver_factory name##_resolver_factory = {                  \
       &name##_factory_vtable}

 #ifdef GRPC_HAVE_UNIX_SOCKET
 DECL_FACTORY(unix);
 #endif
 DECL_FACTORY(ipv4);
 DECL_FACTORY(ipv6);

 void grpc_resolver_sockaddr_init(void) {
   grpc_register_resolver_type(&ipv4_resolver_factory);
   grpc_register_resolver_type(&ipv6_resolver_factory);
 #ifdef GRPC_HAVE_UNIX_SOCKET
   grpc_register_resolver_type(&unix_resolver_factory);
 #endif
 }

 void grpc_resolver_sockaddr_shutdown(void) {}
	/*
	*
	* Copyright 2015-2016 gRPC authors.
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*
	*/

	#include <stdbool.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>

	#include <grpc/support/alloc.h>
	#include <grpc/support/host_port.h>
	#include <grpc/support/port_platform.h>
	#include <grpc/support/string_util.h>

	#include "src/core/ext/filters/client_channel/lb_policy_factory.h"
	#include "src/core/ext/filters/client_channel/parse_address.h"
	#include "src/core/ext/filters/client_channel/resolver_registry.h"
	#include "src/core/lib/channel/channel_args.h"
	#include "src/core/lib/gpr/string.h"
	#include "src/core/lib/iomgr/combiner.h"
	#include "src/core/lib/iomgr/resolve_address.h"
	#include "src/core/lib/iomgr/unix_sockets_posix.h"
	#include "src/core/lib/slice/slice_internal.h"
	#include "src/core/lib/slice/slice_string_helpers.h"

	typedef struct {
	/** base class: must be first */
	grpc_resolver base;
	/** the addresses that we've 'resolved' */
	grpc_lb_addresses* addresses;
	/** channel args */
	grpc_channel_args* channel_args;
	/** have we published? */
	bool published;
	/** pending next completion, or NULL */
	grpc_closure* next_completion;
	/** target result address for next completion */
	grpc_channel_args** target_result;
	} sockaddr_resolver;

	static void sockaddr_destroy(grpc_resolver* r);

	static void sockaddr_maybe_finish_next_locked(sockaddr_resolver* r);

	static void sockaddr_shutdown_locked(grpc_resolver* r);
	static void sockaddr_channel_saw_error_locked(grpc_resolver* r);
	static void sockaddr_next_locked(grpc_resolver* r,
	grpc_channel_args** target_result,
	grpc_closure* on_complete);

	static const grpc_resolver_vtable sockaddr_resolver_vtable = {
	sockaddr_destroy, sockaddr_shutdown_locked,
	sockaddr_channel_saw_error_locked, sockaddr_next_locked};

	static void sockaddr_shutdown_locked(grpc_resolver* resolver) {
	sockaddr_resolver* r = (sockaddr_resolver*)resolver;
	if (r->next_completion != nullptr) {
	*r->target_result = nullptr;
	GRPC_CLOSURE_SCHED(r->next_completion, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
	"Resolver Shutdown"));
	r->next_completion = nullptr;
	}
	}

	static void sockaddr_channel_saw_error_locked(grpc_resolver* resolver) {
	sockaddr_resolver* r = (sockaddr_resolver*)resolver;
	r->published = false;
	sockaddr_maybe_finish_next_locked(r);
	}

	static void sockaddr_next_locked(grpc_resolver* resolver,
	grpc_channel_args** target_result,
	grpc_closure* on_complete) {
	sockaddr_resolver* r = (sockaddr_resolver*)resolver;
	GPR_ASSERT(!r->next_completion);
	r->next_completion = on_complete;
	r->target_result = target_result;
	sockaddr_maybe_finish_next_locked(r);
	}

	static void sockaddr_maybe_finish_next_locked(sockaddr_resolver* r) {
	if (r->next_completion != nullptr && !r->published) {
	r->published = true;
	grpc_arg arg = grpc_lb_addresses_create_channel_arg(r->addresses);
	*r->target_result =
	grpc_channel_args_copy_and_add(r->channel_args, &arg, 1);
	GRPC_CLOSURE_SCHED(r->next_completion, GRPC_ERROR_NONE);
	r->next_completion = nullptr;
	}
	}

	static void sockaddr_destroy(grpc_resolver* gr) {
	sockaddr_resolver* r = (sockaddr_resolver*)gr;
	grpc_lb_addresses_destroy(r->addresses);
	grpc_channel_args_destroy(r->channel_args);
	gpr_free(r);
	}

	static char* ip_get_default_authority(grpc_uri* uri) {
	const char* path = uri->path;
	if (path[0] == '/') ++path;
	return gpr_strdup(path);
	}

	static char* ipv4_get_default_authority(grpc_resolver_factory* factory,
	grpc_uri* uri) {
	return ip_get_default_authority(uri);
	}

	static char* ipv6_get_default_authority(grpc_resolver_factory* factory,
	grpc_uri* uri) {
	return ip_get_default_authority(uri);
	}

	#ifdef GRPC_HAVE_UNIX_SOCKET
	char* unix_get_default_authority(grpc_resolver_factory* factory,
	grpc_uri* uri) {
	return gpr_strdup("localhost");
	}
	#endif

	static void do_nothing(void* ignored) {}

	static grpc_resolver* sockaddr_create(grpc_resolver_args* args,
	bool parse(const grpc_uri* uri,
	grpc_resolved_address* dst)) {
	if (0 != strcmp(args->uri->authority, "")) {
	gpr_log(GPR_ERROR, "authority based uri's not supported by the %s scheme",
	args->uri->scheme);
	return nullptr;
	}
	/* Construct addresses. */
	grpc_slice path_slice =
	grpc_slice_new(args->uri->path, strlen(args->uri->path), do_nothing);
	grpc_slice_buffer path_parts;
	grpc_slice_buffer_init(&path_parts);
	grpc_slice_split(path_slice, ",", &path_parts);
	grpc_lb_addresses* addresses = grpc_lb_addresses_create(
	path_parts.count, nullptr /* user_data_vtable */);
	bool errors_found = false;
	for (size_t i = 0; i < addresses->num_addresses; i++) {
	grpc_uri ith_uri = *args->uri;
	char* part_str = grpc_slice_to_c_string(path_parts.slices[i]);
	ith_uri.path = part_str;
	if (!parse(&ith_uri, &addresses->addresses[i].address)) {
	errors_found = true; /* GPR_TRUE */
	}
	gpr_free(part_str);
	if (errors_found) break;
	}
	grpc_slice_buffer_destroy_internal(&path_parts);
	grpc_slice_unref_internal(path_slice);
	if (errors_found) {
	grpc_lb_addresses_destroy(addresses);
	return nullptr;
	}
	/* Instantiate resolver. */
	sockaddr_resolver* r =
	(sockaddr_resolver*)gpr_zalloc(sizeof(sockaddr_resolver));
	r->addresses = addresses;
	r->channel_args = grpc_channel_args_copy(args->args);
	grpc_resolver_init(&r->base, &sockaddr_resolver_vtable, args->combiner);
	return &r->base;
	}

	/*
	* FACTORY
	*/

	static void sockaddr_factory_ref(grpc_resolver_factory* factory) {}

	static void sockaddr_factory_unref(grpc_resolver_factory* factory) {}

	#define DECL_FACTORY(name) \
	static grpc_resolver* name##_factory_create_resolver( \
	grpc_resolver_factory* factory, grpc_resolver_args* args) { \
	return sockaddr_create(args, grpc_parse_##name); \
	} \
	static const grpc_resolver_factory_vtable name##_factory_vtable = { \
	sockaddr_factory_ref, sockaddr_factory_unref, \
	name##_factory_create_resolver, name##_get_default_authority, #name}; \
	static grpc_resolver_factory name##_resolver_factory = { \
	&name##_factory_vtable}

	#ifdef GRPC_HAVE_UNIX_SOCKET
	DECL_FACTORY(unix);
	#endif
	DECL_FACTORY(ipv4);
	DECL_FACTORY(ipv6);

	void grpc_resolver_sockaddr_init(void) {
	grpc_register_resolver_type(&ipv4_resolver_factory);
	grpc_register_resolver_type(&ipv6_resolver_factory);
	#ifdef GRPC_HAVE_UNIX_SOCKET
	grpc_register_resolver_type(&unix_resolver_factory);
	#endif
	}

	void grpc_resolver_sockaddr_shutdown(void) {}