src/core/ext/resolver/sockaddr/sockaddr_resolver.c - platform/external/grpc-grpc - Gitiles

 /*
  *
  * Copyright 2015-2016, 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 <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/client_channel/lb_policy_factory.h"
 #include "src/core/ext/client_channel/parse_address.h"
 #include "src/core/ext/client_channel/resolver_registry.h"
 #include "src/core/lib/channel/channel_args.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"
 #include "src/core/lib/support/string.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_exec_ctx *exec_ctx, grpc_resolver *r);

 static void sockaddr_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
                                               sockaddr_resolver *r);

 static void sockaddr_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_resolver *r);
 static void sockaddr_channel_saw_error_locked(grpc_exec_ctx *exec_ctx,
                                               grpc_resolver *r);
 static void sockaddr_next_locked(grpc_exec_ctx *exec_ctx, 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_exec_ctx *exec_ctx,
                                      grpc_resolver *resolver) {
   sockaddr_resolver *r = (sockaddr_resolver *)resolver;
   if (r->next_completion != NULL) {
     *r->target_result = NULL;
     grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
   }
 }

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

 static void sockaddr_next_locked(grpc_exec_ctx *exec_ctx,
                                  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(exec_ctx, r);
 }

 static void sockaddr_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
                                               sockaddr_resolver *r) {
   if (r->next_completion != NULL && !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(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
     r->next_completion = NULL;
   }
 }

 static void sockaddr_destroy(grpc_exec_ctx *exec_ctx, grpc_resolver *gr) {
   sockaddr_resolver *r = (sockaddr_resolver *)gr;
   grpc_lb_addresses_destroy(exec_ctx, r->addresses);
   grpc_channel_args_destroy(exec_ctx, 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_exec_ctx *exec_ctx,
                                       grpc_resolver_args *args,
                                       int parse(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 NULL;
   }
   /* 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, NULL /* 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(exec_ctx, &path_parts);
   grpc_slice_unref_internal(exec_ctx, path_slice);
   if (errors_found) {
     grpc_lb_addresses_destroy(exec_ctx, addresses);
     return NULL;
   }
   /* Instantiate resolver. */
   sockaddr_resolver *r = gpr_malloc(sizeof(sockaddr_resolver));
   memset(r, 0, sizeof(*r));
   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_exec_ctx *exec_ctx, grpc_resolver_factory *factory,              \
       grpc_resolver_args *args) {                                           \
     return sockaddr_create(exec_ctx, args, 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, 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 <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/client_channel/lb_policy_factory.h"
	#include "src/core/ext/client_channel/parse_address.h"
	#include "src/core/ext/client_channel/resolver_registry.h"
	#include "src/core/lib/channel/channel_args.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"
	#include "src/core/lib/support/string.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_exec_ctx exec_ctx, grpc_resolver r);

	static void sockaddr_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
	sockaddr_resolver *r);

	static void sockaddr_shutdown_locked(grpc_exec_ctx exec_ctx, grpc_resolver r);
	static void sockaddr_channel_saw_error_locked(grpc_exec_ctx *exec_ctx,
	grpc_resolver *r);
	static void sockaddr_next_locked(grpc_exec_ctx exec_ctx, 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_exec_ctx *exec_ctx,
	grpc_resolver *resolver) {
	sockaddr_resolver r = (sockaddr_resolver )resolver;
	if (r->next_completion != NULL) {
	*r->target_result = NULL;
	grpc_closure_sched(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
	r->next_completion = NULL;
	}
	}

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

	static void sockaddr_next_locked(grpc_exec_ctx *exec_ctx,
	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(exec_ctx, r);
	}

	static void sockaddr_maybe_finish_next_locked(grpc_exec_ctx *exec_ctx,
	sockaddr_resolver *r) {
	if (r->next_completion != NULL && !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(exec_ctx, r->next_completion, GRPC_ERROR_NONE);
	r->next_completion = NULL;
	}
	}

	static void sockaddr_destroy(grpc_exec_ctx exec_ctx, grpc_resolver gr) {
	sockaddr_resolver r = (sockaddr_resolver )gr;
	grpc_lb_addresses_destroy(exec_ctx, r->addresses);
	grpc_channel_args_destroy(exec_ctx, 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_exec_ctx exec_ctx,
	grpc_resolver_args *args,
	int parse(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 NULL;
	}
	/* 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, NULL /* 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(exec_ctx, &path_parts);
	grpc_slice_unref_internal(exec_ctx, path_slice);
	if (errors_found) {
	grpc_lb_addresses_destroy(exec_ctx, addresses);
	return NULL;
	}
	/* Instantiate resolver. */
	sockaddr_resolver *r = gpr_malloc(sizeof(sockaddr_resolver));
	memset(r, 0, sizeof(*r));
	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_exec_ctx exec_ctx, grpc_resolver_factory factory, \
	grpc_resolver_args *args) { \
	return sockaddr_create(exec_ctx, args, 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) {}