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Diffstat (limited to 'src/core/ext/filters/client_channel/resolver/dns')
-rw-r--r--src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c6
-rw-r--r--src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c82
-rw-r--r--src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c36
3 files changed, 81 insertions, 43 deletions
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
index b87a3b7082..9bb229ad95 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.c
@@ -204,7 +204,7 @@ static char *choose_service_config(char *service_config_choice_json) {
int random_pct = rand() % 100;
int percentage;
if (sscanf(field->value, "%d", &percentage) != 1 ||
- random_pct > percentage) {
+ random_pct > percentage || percentage == 0) {
service_config_json = NULL;
break;
}
@@ -249,7 +249,7 @@ static void dns_ares_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
service_config_string);
args_to_remove[num_args_to_remove++] = GRPC_ARG_SERVICE_CONFIG;
new_args[num_args_to_add++] = grpc_channel_arg_string_create(
- GRPC_ARG_SERVICE_CONFIG, service_config_string);
+ (char *)GRPC_ARG_SERVICE_CONFIG, service_config_string);
service_config = grpc_service_config_create(service_config_string);
if (service_config != NULL) {
const char *lb_policy_name =
@@ -257,7 +257,7 @@ static void dns_ares_on_resolved_locked(grpc_exec_ctx *exec_ctx, void *arg,
if (lb_policy_name != NULL) {
args_to_remove[num_args_to_remove++] = GRPC_ARG_LB_POLICY_NAME;
new_args[num_args_to_add++] = grpc_channel_arg_string_create(
- GRPC_ARG_LB_POLICY_NAME, (char *)lb_policy_name);
+ (char *)GRPC_ARG_LB_POLICY_NAME, (char *)lb_policy_name);
}
}
}
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
index 9747d39a16..c30cc93b6f 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.c
@@ -20,6 +20,7 @@
#if GRPC_ARES == 1 && defined(GRPC_POSIX_SOCKET)
#include <ares.h>
+#include <sys/ioctl.h>
#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h"
@@ -37,8 +38,6 @@
typedef struct fd_node {
/** the owner of this fd node */
grpc_ares_ev_driver *ev_driver;
- /** the grpc_fd owned by this fd node */
- grpc_fd *grpc_fd;
/** a closure wrapping on_readable_cb, which should be invoked when the
grpc_fd in this node becomes readable. */
grpc_closure read_closure;
@@ -50,10 +49,14 @@ typedef struct fd_node {
/** mutex guarding the rest of the state */
gpr_mu mu;
+ /** the grpc_fd owned by this fd node */
+ grpc_fd *fd;
/** if the readable closure has been registered */
bool readable_registered;
/** if the writable closure has been registered */
bool writable_registered;
+ /** if the fd is being shut down */
+ bool shutting_down;
} fd_node;
struct grpc_ares_ev_driver {
@@ -96,19 +99,31 @@ static void grpc_ares_ev_driver_unref(grpc_ares_ev_driver *ev_driver) {
}
static void fd_node_destroy(grpc_exec_ctx *exec_ctx, fd_node *fdn) {
- gpr_log(GPR_DEBUG, "delete fd: %d", grpc_fd_wrapped_fd(fdn->grpc_fd));
+ gpr_log(GPR_DEBUG, "delete fd: %d", grpc_fd_wrapped_fd(fdn->fd));
GPR_ASSERT(!fdn->readable_registered);
GPR_ASSERT(!fdn->writable_registered);
gpr_mu_destroy(&fdn->mu);
- grpc_pollset_set_del_fd(exec_ctx, fdn->ev_driver->pollset_set, fdn->grpc_fd);
/* c-ares library has closed the fd inside grpc_fd. This fd may be picked up
immediately by another thread, and should not be closed by the following
grpc_fd_orphan. */
- grpc_fd_orphan(exec_ctx, fdn->grpc_fd, NULL, NULL, true /* already_closed */,
+ grpc_fd_orphan(exec_ctx, fdn->fd, NULL, NULL, true /* already_closed */,
"c-ares query finished");
gpr_free(fdn);
}
+static void fd_node_shutdown(grpc_exec_ctx *exec_ctx, fd_node *fdn) {
+ gpr_mu_lock(&fdn->mu);
+ fdn->shutting_down = true;
+ if (!fdn->readable_registered && !fdn->writable_registered) {
+ gpr_mu_unlock(&fdn->mu);
+ fd_node_destroy(exec_ctx, fdn);
+ } else {
+ grpc_fd_shutdown(exec_ctx, fdn->fd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+ "c-ares fd shutdown"));
+ gpr_mu_unlock(&fdn->mu);
+ }
+}
+
grpc_error *grpc_ares_ev_driver_create(grpc_ares_ev_driver **ev_driver,
grpc_pollset_set *pollset_set) {
*ev_driver = (grpc_ares_ev_driver *)gpr_malloc(sizeof(grpc_ares_ev_driver));
@@ -150,9 +165,8 @@ void grpc_ares_ev_driver_shutdown(grpc_exec_ctx *exec_ctx,
ev_driver->shutting_down = true;
fd_node *fn = ev_driver->fds;
while (fn != NULL) {
- grpc_fd_shutdown(
- exec_ctx, fn->grpc_fd,
- GRPC_ERROR_CREATE_FROM_STATIC_STRING("grpc_ares_ev_driver_shutdown"));
+ grpc_fd_shutdown(exec_ctx, fn->fd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+ "grpc_ares_ev_driver_shutdown"));
fn = fn->next;
}
gpr_mu_unlock(&ev_driver->mu);
@@ -165,7 +179,7 @@ static fd_node *pop_fd_node(fd_node **head, int fd) {
dummy_head.next = *head;
fd_node *node = &dummy_head;
while (node->next != NULL) {
- if (grpc_fd_wrapped_fd(node->next->grpc_fd) == fd) {
+ if (grpc_fd_wrapped_fd(node->next->fd) == fd) {
fd_node *ret = node->next;
node->next = node->next->next;
*head = dummy_head.next;
@@ -176,18 +190,33 @@ static fd_node *pop_fd_node(fd_node **head, int fd) {
return NULL;
}
+/* Check if \a fd is still readable */
+static bool grpc_ares_is_fd_still_readable(grpc_ares_ev_driver *ev_driver,
+ int fd) {
+ size_t bytes_available = 0;
+ return ioctl(fd, FIONREAD, &bytes_available) == 0 && bytes_available > 0;
+}
+
static void on_readable_cb(grpc_exec_ctx *exec_ctx, void *arg,
grpc_error *error) {
fd_node *fdn = (fd_node *)arg;
grpc_ares_ev_driver *ev_driver = fdn->ev_driver;
gpr_mu_lock(&fdn->mu);
+ const int fd = grpc_fd_wrapped_fd(fdn->fd);
fdn->readable_registered = false;
+ if (fdn->shutting_down && !fdn->writable_registered) {
+ gpr_mu_unlock(&fdn->mu);
+ fd_node_destroy(exec_ctx, fdn);
+ grpc_ares_ev_driver_unref(ev_driver);
+ return;
+ }
gpr_mu_unlock(&fdn->mu);
- gpr_log(GPR_DEBUG, "readable on %d", grpc_fd_wrapped_fd(fdn->grpc_fd));
+ gpr_log(GPR_DEBUG, "readable on %d", fd);
if (error == GRPC_ERROR_NONE) {
- ares_process_fd(ev_driver->channel, grpc_fd_wrapped_fd(fdn->grpc_fd),
- ARES_SOCKET_BAD);
+ do {
+ ares_process_fd(ev_driver->channel, fd, ARES_SOCKET_BAD);
+ } while (grpc_ares_is_fd_still_readable(ev_driver, fd));
} else {
// If error is not GRPC_ERROR_NONE, it means the fd has been shutdown or
// timed out. The pending lookups made on this ev_driver will be cancelled
@@ -208,13 +237,19 @@ static void on_writable_cb(grpc_exec_ctx *exec_ctx, void *arg,
fd_node *fdn = (fd_node *)arg;
grpc_ares_ev_driver *ev_driver = fdn->ev_driver;
gpr_mu_lock(&fdn->mu);
+ const int fd = grpc_fd_wrapped_fd(fdn->fd);
fdn->writable_registered = false;
+ if (fdn->shutting_down && !fdn->readable_registered) {
+ gpr_mu_unlock(&fdn->mu);
+ fd_node_destroy(exec_ctx, fdn);
+ grpc_ares_ev_driver_unref(ev_driver);
+ return;
+ }
gpr_mu_unlock(&fdn->mu);
- gpr_log(GPR_DEBUG, "writable on %d", grpc_fd_wrapped_fd(fdn->grpc_fd));
+ gpr_log(GPR_DEBUG, "writable on %d", fd);
if (error == GRPC_ERROR_NONE) {
- ares_process_fd(ev_driver->channel, ARES_SOCKET_BAD,
- grpc_fd_wrapped_fd(fdn->grpc_fd));
+ ares_process_fd(ev_driver->channel, ARES_SOCKET_BAD, fd);
} else {
// If error is not GRPC_ERROR_NONE, it means the fd has been shutdown or
// timed out. The pending lookups made on this ev_driver will be cancelled
@@ -253,17 +288,17 @@ static void grpc_ares_notify_on_event_locked(grpc_exec_ctx *exec_ctx,
gpr_asprintf(&fd_name, "ares_ev_driver-%" PRIuPTR, i);
fdn = (fd_node *)gpr_malloc(sizeof(fd_node));
gpr_log(GPR_DEBUG, "new fd: %d", socks[i]);
- fdn->grpc_fd = grpc_fd_create(socks[i], fd_name);
+ fdn->fd = grpc_fd_create(socks[i], fd_name);
fdn->ev_driver = ev_driver;
fdn->readable_registered = false;
fdn->writable_registered = false;
+ fdn->shutting_down = false;
gpr_mu_init(&fdn->mu);
GRPC_CLOSURE_INIT(&fdn->read_closure, on_readable_cb, fdn,
grpc_schedule_on_exec_ctx);
GRPC_CLOSURE_INIT(&fdn->write_closure, on_writable_cb, fdn,
grpc_schedule_on_exec_ctx);
- grpc_pollset_set_add_fd(exec_ctx, ev_driver->pollset_set,
- fdn->grpc_fd);
+ grpc_pollset_set_add_fd(exec_ctx, ev_driver->pollset_set, fdn->fd);
gpr_free(fd_name);
}
fdn->next = new_list;
@@ -274,9 +309,8 @@ static void grpc_ares_notify_on_event_locked(grpc_exec_ctx *exec_ctx,
if (ARES_GETSOCK_READABLE(socks_bitmask, i) &&
!fdn->readable_registered) {
grpc_ares_ev_driver_ref(ev_driver);
- gpr_log(GPR_DEBUG, "notify read on: %d",
- grpc_fd_wrapped_fd(fdn->grpc_fd));
- grpc_fd_notify_on_read(exec_ctx, fdn->grpc_fd, &fdn->read_closure);
+ gpr_log(GPR_DEBUG, "notify read on: %d", grpc_fd_wrapped_fd(fdn->fd));
+ grpc_fd_notify_on_read(exec_ctx, fdn->fd, &fdn->read_closure);
fdn->readable_registered = true;
}
// Register write_closure if the socket is writable and write_closure
@@ -284,9 +318,9 @@ static void grpc_ares_notify_on_event_locked(grpc_exec_ctx *exec_ctx,
if (ARES_GETSOCK_WRITABLE(socks_bitmask, i) &&
!fdn->writable_registered) {
gpr_log(GPR_DEBUG, "notify write on: %d",
- grpc_fd_wrapped_fd(fdn->grpc_fd));
+ grpc_fd_wrapped_fd(fdn->fd));
grpc_ares_ev_driver_ref(ev_driver);
- grpc_fd_notify_on_write(exec_ctx, fdn->grpc_fd, &fdn->write_closure);
+ grpc_fd_notify_on_write(exec_ctx, fdn->fd, &fdn->write_closure);
fdn->writable_registered = true;
}
gpr_mu_unlock(&fdn->mu);
@@ -299,7 +333,7 @@ static void grpc_ares_notify_on_event_locked(grpc_exec_ctx *exec_ctx,
while (ev_driver->fds != NULL) {
fd_node *cur = ev_driver->fds;
ev_driver->fds = ev_driver->fds->next;
- fd_node_destroy(exec_ctx, cur);
+ fd_node_shutdown(exec_ctx, cur);
}
ev_driver->fds = new_list;
// If the ev driver has no working fd, all the tasks are done.
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
index 0d71f3560e..04379975e1 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.c
@@ -123,8 +123,8 @@ static void grpc_ares_request_unref(grpc_exec_ctx *exec_ctx,
static grpc_ares_hostbyname_request *create_hostbyname_request(
grpc_ares_request *parent_request, char *host, uint16_t port,
bool is_balancer) {
- grpc_ares_hostbyname_request *hr =
- gpr_zalloc(sizeof(grpc_ares_hostbyname_request));
+ grpc_ares_hostbyname_request *hr = (grpc_ares_hostbyname_request *)gpr_zalloc(
+ sizeof(grpc_ares_hostbyname_request));
hr->parent_request = parent_request;
hr->host = gpr_strdup(host);
hr->port = port;
@@ -174,7 +174,7 @@ static void on_hostbyname_done_cb(void *arg, int status, int timeouts,
grpc_lb_addresses_set_address(
*lb_addresses, i, &addr, addr_len,
hr->is_balancer /* is_balancer */,
- hr->is_balancer ? strdup(hr->host) : NULL /* balancer_name */,
+ hr->is_balancer ? hr->host : NULL /* balancer_name */,
NULL /* user_data */);
char output[INET6_ADDRSTRLEN];
ares_inet_ntop(AF_INET6, &addr.sin6_addr, output, INET6_ADDRSTRLEN);
@@ -195,7 +195,7 @@ static void on_hostbyname_done_cb(void *arg, int status, int timeouts,
grpc_lb_addresses_set_address(
*lb_addresses, i, &addr, addr_len,
hr->is_balancer /* is_balancer */,
- hr->is_balancer ? strdup(hr->host) : NULL /* balancer_name */,
+ hr->is_balancer ? hr->host : NULL /* balancer_name */,
NULL /* user_data */);
char output[INET_ADDRSTRLEN];
ares_inet_ntop(AF_INET, &addr.sin_addr, output, INET_ADDRSTRLEN);
@@ -275,14 +275,15 @@ static void on_txt_done_cb(void *arg, int status, int timeouts,
gpr_log(GPR_DEBUG, "on_txt_done_cb");
char *error_msg;
grpc_ares_request *r = (grpc_ares_request *)arg;
+ const size_t prefix_len = sizeof(g_service_config_attribute_prefix) - 1;
+ struct ares_txt_ext *result = NULL;
+ struct ares_txt_ext *reply = NULL;
+ grpc_error *error = GRPC_ERROR_NONE;
gpr_mu_lock(&r->mu);
if (status != ARES_SUCCESS) goto fail;
- struct ares_txt_ext *reply = NULL;
status = ares_parse_txt_reply_ext(buf, len, &reply);
if (status != ARES_SUCCESS) goto fail;
// Find service config in TXT record.
- const size_t prefix_len = sizeof(g_service_config_attribute_prefix) - 1;
- struct ares_txt_ext *result;
for (result = reply; result != NULL; result = result->next) {
if (result->record_start &&
memcmp(result->txt, g_service_config_attribute_prefix, prefix_len) ==
@@ -313,7 +314,7 @@ static void on_txt_done_cb(void *arg, int status, int timeouts,
fail:
gpr_asprintf(&error_msg, "C-ares TXT lookup status is not ARES_SUCCESS: %s",
ares_strerror(status));
- grpc_error *error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg);
+ error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg);
gpr_free(error_msg);
if (r->error == GRPC_ERROR_NONE) {
r->error = error;
@@ -331,6 +332,9 @@ static grpc_ares_request *grpc_dns_lookup_ares_impl(
grpc_closure *on_done, grpc_lb_addresses **addrs, bool check_grpclb,
char **service_config_json) {
grpc_error *error = GRPC_ERROR_NONE;
+ grpc_ares_hostbyname_request *hr = NULL;
+ grpc_ares_request *r = NULL;
+ ares_channel *channel = NULL;
/* TODO(zyc): Enable tracing after #9603 is checked in */
/* if (grpc_dns_trace) {
gpr_log(GPR_DEBUG, "resolve_address (blocking): name=%s, default_port=%s",
@@ -360,8 +364,7 @@ static grpc_ares_request *grpc_dns_lookup_ares_impl(
error = grpc_ares_ev_driver_create(&ev_driver, interested_parties);
if (error != GRPC_ERROR_NONE) goto error_cleanup;
- grpc_ares_request *r =
- (grpc_ares_request *)gpr_zalloc(sizeof(grpc_ares_request));
+ r = (grpc_ares_request *)gpr_zalloc(sizeof(grpc_ares_request));
gpr_mu_init(&r->mu);
r->ev_driver = ev_driver;
r->on_done = on_done;
@@ -369,7 +372,7 @@ static grpc_ares_request *grpc_dns_lookup_ares_impl(
r->service_config_json_out = service_config_json;
r->success = false;
r->error = GRPC_ERROR_NONE;
- ares_channel *channel = grpc_ares_ev_driver_get_channel(r->ev_driver);
+ channel = grpc_ares_ev_driver_get_channel(r->ev_driver);
// If dns_server is specified, use it.
if (dns_server != NULL) {
@@ -410,12 +413,12 @@ static grpc_ares_request *grpc_dns_lookup_ares_impl(
}
gpr_ref_init(&r->pending_queries, 1);
if (grpc_ipv6_loopback_available()) {
- grpc_ares_hostbyname_request *hr = create_hostbyname_request(
- r, host, strhtons(port), false /* is_balancer */);
+ hr = create_hostbyname_request(r, host, strhtons(port),
+ false /* is_balancer */);
ares_gethostbyname(*channel, hr->host, AF_INET6, on_hostbyname_done_cb, hr);
}
- grpc_ares_hostbyname_request *hr = create_hostbyname_request(
- r, host, strhtons(port), false /* is_balancer */);
+ hr = create_hostbyname_request(r, host, strhtons(port),
+ false /* is_balancer */);
ares_gethostbyname(*channel, hr->host, AF_INET, on_hostbyname_done_cb, hr);
if (check_grpclb) {
/* Query the SRV record */
@@ -527,7 +530,8 @@ static void grpc_resolve_address_ares_impl(grpc_exec_ctx *exec_ctx,
grpc_closure *on_done,
grpc_resolved_addresses **addrs) {
grpc_resolve_address_ares_request *r =
- gpr_zalloc(sizeof(grpc_resolve_address_ares_request));
+ (grpc_resolve_address_ares_request *)gpr_zalloc(
+ sizeof(grpc_resolve_address_ares_request));
r->addrs_out = addrs;
r->on_resolve_address_done = on_done;
GRPC_CLOSURE_INIT(&r->on_dns_lookup_done, on_dns_lookup_done_cb, r,