Separate the posix part of the c-ares driver
diff --git a/BUILD b/BUILD
index 3df4be8..44b8777 100644
--- a/BUILD
+++ b/BUILD
@@ -1333,6 +1333,7 @@
name = "grpc_resolver_dns_ares",
srcs = [
"src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc",
+ "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc",
"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc",
"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc",
"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc",
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1bcac91..4dc8d98 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1213,6 +1213,7 @@
src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc
src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc
+ src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc
@@ -2503,6 +2504,7 @@
src/core/ext/transport/inproc/inproc_plugin.cc
src/core/ext/transport/inproc/inproc_transport.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc
+ src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc
diff --git a/Makefile b/Makefile
index 1b4fc6a..ab60451 100644
--- a/Makefile
+++ b/Makefile
@@ -3588,6 +3588,7 @@
src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc \
src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc \
+ src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc \
@@ -4844,6 +4845,7 @@
src/core/ext/transport/inproc/inproc_plugin.cc \
src/core/ext/transport/inproc/inproc_transport.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc \
+ src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc \
diff --git a/build.yaml b/build.yaml
index ffe2feb..11060b6 100644
--- a/build.yaml
+++ b/build.yaml
@@ -725,6 +725,7 @@
- src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h
src:
- src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc
+ - src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc
- src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc
- src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc
- src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc
diff --git a/config.m4 b/config.m4
index 8190485..a5b041f 100644
--- a/config.m4
+++ b/config.m4
@@ -370,6 +370,7 @@
src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc \
src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc \
+ src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc \
diff --git a/config.w32 b/config.w32
index db7679c..cd51b4d 100644
--- a/config.w32
+++ b/config.w32
@@ -346,6 +346,7 @@
"src\\core\\ext\\filters\\client_channel\\lb_policy\\pick_first\\pick_first.cc " +
"src\\core\\ext\\filters\\client_channel\\lb_policy\\round_robin\\round_robin.cc " +
"src\\core\\ext\\filters\\client_channel\\resolver\\dns\\c_ares\\dns_resolver_ares.cc " +
+ "src\\core\\ext\\filters\\client_channel\\resolver\\dns\\c_ares\\grpc_ares_ev_driver.cc " +
"src\\core\\ext\\filters\\client_channel\\resolver\\dns\\c_ares\\grpc_ares_ev_driver_posix.cc " +
"src\\core\\ext\\filters\\client_channel\\resolver\\dns\\c_ares\\grpc_ares_wrapper.cc " +
"src\\core\\ext\\filters\\client_channel\\resolver\\dns\\c_ares\\grpc_ares_wrapper_fallback.cc " +
diff --git a/gRPC-Core.podspec b/gRPC-Core.podspec
index 399368bab..ca6df16 100644
--- a/gRPC-Core.podspec
+++ b/gRPC-Core.podspec
@@ -785,6 +785,7 @@
'src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc',
'src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc',
+ 'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc',
diff --git a/grpc.gemspec b/grpc.gemspec
index 5ab3713..1a3b5bd 100644
--- a/grpc.gemspec
+++ b/grpc.gemspec
@@ -725,6 +725,7 @@
s.files += %w( src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc )
s.files += %w( src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc )
s.files += %w( src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc )
+ s.files += %w( src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc )
s.files += %w( src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc )
s.files += %w( src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc )
s.files += %w( src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc )
diff --git a/grpc.gyp b/grpc.gyp
index f893862..20e463e 100644
--- a/grpc.gyp
+++ b/grpc.gyp
@@ -536,6 +536,7 @@
'src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc',
'src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc',
+ 'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc',
@@ -1246,6 +1247,7 @@
'src/core/ext/transport/inproc/inproc_plugin.cc',
'src/core/ext/transport/inproc/inproc_transport.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc',
+ 'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc',
diff --git a/package.xml b/package.xml
index 220256c..5be18bd 100644
--- a/package.xml
+++ b/package.xml
@@ -730,6 +730,7 @@
<file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc" role="src" />
<file baseinstalldir="/" name="src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc" role="src" />
<file baseinstalldir="/" name="src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc" role="src" />
+ <file baseinstalldir="/" name="src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc" role="src" />
<file baseinstalldir="/" name="src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc" role="src" />
<file baseinstalldir="/" name="src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc" role="src" />
<file baseinstalldir="/" name="src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc" role="src" />
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc
new file mode 100644
index 0000000..06a6e85
--- /dev/null
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc
@@ -0,0 +1,311 @@
+/*
+ *
+ * Copyright 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 <grpc/support/port_platform.h>
+
+#include "src/core/lib/iomgr/port.h"
+#if GRPC_ARES == 1 && defined(GRPC_POSIX_SOCKET_ARES_EV_DRIVER)
+
+#include <ares.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h"
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/time.h>
+#include "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.h"
+#include "src/core/lib/gpr/string.h"
+#include "src/core/lib/iomgr/ev_posix.h"
+#include "src/core/lib/iomgr/iomgr_internal.h"
+#include "src/core/lib/iomgr/sockaddr_utils.h"
+
+typedef struct fd_node {
+ /** the owner of this fd node */
+ grpc_ares_ev_driver* ev_driver;
+ /** a closure wrapping on_readable_locked, which should be
+ invoked when the grpc_fd in this node becomes readable. */
+ grpc_closure read_closure;
+ /** a closure wrapping on_writable_locked, which should be
+ invoked when the grpc_fd in this node becomes writable. */
+ grpc_closure write_closure;
+ /** next fd node in the list */
+ struct fd_node* next;
+
+ /** wrapped fd that's polled by grpc's poller for the current platform */
+ grpc_core::GrpcPolledFd* grpc_polled_fd;
+ /** if the readable closure has been registered */
+ bool readable_registered;
+ /** if the writable closure has been registered */
+ bool writable_registered;
+ /** if the fd has been shutdown yet from grpc iomgr perspective */
+ bool already_shutdown;
+} fd_node;
+
+struct grpc_ares_ev_driver {
+ /** the ares_channel owned by this event driver */
+ ares_channel channel;
+ /** pollset set for driving the IO events of the channel */
+ grpc_pollset_set* pollset_set;
+ /** refcount of the event driver */
+ gpr_refcount refs;
+
+ /** combiner to synchronize c-ares and I/O callbacks on */
+ grpc_combiner* combiner;
+ /** a list of grpc_fd that this event driver is currently using. */
+ fd_node* fds;
+ /** is this event driver currently working? */
+ bool working;
+ /** is this event driver being shut down */
+ bool shutting_down;
+};
+
+static void grpc_ares_notify_on_event_locked(grpc_ares_ev_driver* ev_driver);
+
+static grpc_ares_ev_driver* grpc_ares_ev_driver_ref(
+ grpc_ares_ev_driver* ev_driver) {
+ gpr_log(GPR_DEBUG, "Ref ev_driver %" PRIuPTR, (uintptr_t)ev_driver);
+ gpr_ref(&ev_driver->refs);
+ return ev_driver;
+}
+
+static void grpc_ares_ev_driver_unref(grpc_ares_ev_driver* ev_driver) {
+ gpr_log(GPR_DEBUG, "Unref ev_driver %" PRIuPTR, (uintptr_t)ev_driver);
+ if (gpr_unref(&ev_driver->refs)) {
+ gpr_log(GPR_DEBUG, "destroy ev_driver %" PRIuPTR, (uintptr_t)ev_driver);
+ GPR_ASSERT(ev_driver->fds == nullptr);
+ GRPC_COMBINER_UNREF(ev_driver->combiner, "free ares event driver");
+ ares_destroy(ev_driver->channel);
+ gpr_free(ev_driver);
+ }
+}
+
+static void fd_node_destroy_locked(fd_node* fdn) {
+ gpr_log(GPR_DEBUG, "delete fd: %s", fdn->grpc_polled_fd->GetName());
+ GPR_ASSERT(!fdn->readable_registered);
+ GPR_ASSERT(!fdn->writable_registered);
+ GPR_ASSERT(fdn->already_shutdown);
+ grpc_core::Delete(fdn->grpc_polled_fd);
+ gpr_free(fdn);
+}
+
+static void fd_node_shutdown_locked(fd_node* fdn, const char* reason) {
+ if (!fdn->already_shutdown) {
+ fdn->already_shutdown = true;
+ fdn->grpc_polled_fd->ShutdownLocked(
+ GRPC_ERROR_CREATE_FROM_STATIC_STRING(reason));
+ }
+}
+
+grpc_error* grpc_ares_ev_driver_create_locked(grpc_ares_ev_driver** ev_driver,
+ grpc_pollset_set* pollset_set,
+ grpc_combiner* combiner) {
+ *ev_driver = static_cast<grpc_ares_ev_driver*>(
+ gpr_malloc(sizeof(grpc_ares_ev_driver)));
+ ares_options opts;
+ memset(&opts, 0, sizeof(opts));
+ opts.flags |= ARES_FLAG_STAYOPEN;
+ int status = ares_init_options(&(*ev_driver)->channel, &opts, ARES_OPT_FLAGS);
+ grpc_core::ConfigureAresChannelLocked(&(*ev_driver)->channel);
+ gpr_log(GPR_DEBUG, "grpc_ares_ev_driver_create_locked");
+ if (status != ARES_SUCCESS) {
+ char* err_msg;
+ gpr_asprintf(&err_msg, "Failed to init ares channel. C-ares error: %s",
+ ares_strerror(status));
+ grpc_error* err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_msg);
+ gpr_free(err_msg);
+ gpr_free(*ev_driver);
+ return err;
+ }
+ (*ev_driver)->combiner = GRPC_COMBINER_REF(combiner, "ares event driver");
+ gpr_ref_init(&(*ev_driver)->refs, 1);
+ (*ev_driver)->pollset_set = pollset_set;
+ (*ev_driver)->fds = nullptr;
+ (*ev_driver)->working = false;
+ (*ev_driver)->shutting_down = false;
+ return GRPC_ERROR_NONE;
+}
+
+void grpc_ares_ev_driver_destroy_locked(grpc_ares_ev_driver* ev_driver) {
+ // We mark the event driver as being shut down. If the event driver
+ // is working, grpc_ares_notify_on_event_locked will shut down the
+ // fds; if it's not working, there are no fds to shut down.
+ ev_driver->shutting_down = true;
+ grpc_ares_ev_driver_unref(ev_driver);
+}
+
+void grpc_ares_ev_driver_shutdown_locked(grpc_ares_ev_driver* ev_driver) {
+ ev_driver->shutting_down = true;
+ fd_node* fn = ev_driver->fds;
+ while (fn != nullptr) {
+ fd_node_shutdown_locked(fn, "grpc_ares_ev_driver_shutdown");
+ fn = fn->next;
+ }
+}
+
+// Search fd in the fd_node list head. This is an O(n) search, the max possible
+// value of n is ARES_GETSOCK_MAXNUM (16). n is typically 1 - 2 in our tests.
+static fd_node* pop_fd_node_locked(fd_node** head, ares_socket_t as) {
+ fd_node dummy_head;
+ dummy_head.next = *head;
+ fd_node* node = &dummy_head;
+ while (node->next != nullptr) {
+ if (node->next->grpc_polled_fd->GetWrappedAresSocketLocked() == as) {
+ fd_node* ret = node->next;
+ node->next = node->next->next;
+ *head = dummy_head.next;
+ return ret;
+ }
+ node = node->next;
+ }
+ return nullptr;
+}
+
+static void on_readable_locked(void* arg, grpc_error* error) {
+ fd_node* fdn = static_cast<fd_node*>(arg);
+ grpc_ares_ev_driver* ev_driver = fdn->ev_driver;
+ const ares_socket_t as = fdn->grpc_polled_fd->GetWrappedAresSocketLocked();
+ fdn->readable_registered = false;
+ gpr_log(GPR_DEBUG, "readable on %s", fdn->grpc_polled_fd->GetName());
+ if (error == GRPC_ERROR_NONE) {
+ do {
+ ares_process_fd(ev_driver->channel, as, ARES_SOCKET_BAD);
+ } while (fdn->grpc_polled_fd->IsFdStillReadableLocked());
+ } 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
+ // by the following ares_cancel() and the on_done callbacks will be invoked
+ // with a status of ARES_ECANCELLED. The remaining file descriptors in this
+ // ev_driver will be cleaned up in the follwing
+ // grpc_ares_notify_on_event_locked().
+ ares_cancel(ev_driver->channel);
+ }
+ grpc_ares_notify_on_event_locked(ev_driver);
+ grpc_ares_ev_driver_unref(ev_driver);
+}
+
+static void on_writable_locked(void* arg, grpc_error* error) {
+ fd_node* fdn = static_cast<fd_node*>(arg);
+ grpc_ares_ev_driver* ev_driver = fdn->ev_driver;
+ const ares_socket_t as = fdn->grpc_polled_fd->GetWrappedAresSocketLocked();
+ fdn->writable_registered = false;
+ gpr_log(GPR_DEBUG, "writable on %s", fdn->grpc_polled_fd->GetName());
+ if (error == GRPC_ERROR_NONE) {
+ ares_process_fd(ev_driver->channel, ARES_SOCKET_BAD, as);
+ } 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
+ // by the following ares_cancel() and the on_done callbacks will be invoked
+ // with a status of ARES_ECANCELLED. The remaining file descriptors in this
+ // ev_driver will be cleaned up in the follwing
+ // grpc_ares_notify_on_event_locked().
+ ares_cancel(ev_driver->channel);
+ }
+ grpc_ares_notify_on_event_locked(ev_driver);
+ grpc_ares_ev_driver_unref(ev_driver);
+}
+
+ares_channel* grpc_ares_ev_driver_get_channel_locked(
+ grpc_ares_ev_driver* ev_driver) {
+ return &ev_driver->channel;
+}
+
+// Get the file descriptors used by the ev_driver's ares channel, register
+// driver_closure with these filedescriptors.
+static void grpc_ares_notify_on_event_locked(grpc_ares_ev_driver* ev_driver) {
+ fd_node* new_list = nullptr;
+ if (!ev_driver->shutting_down) {
+ ares_socket_t socks[ARES_GETSOCK_MAXNUM];
+ int socks_bitmask =
+ ares_getsock(ev_driver->channel, socks, ARES_GETSOCK_MAXNUM);
+ for (size_t i = 0; i < ARES_GETSOCK_MAXNUM; i++) {
+ if (ARES_GETSOCK_READABLE(socks_bitmask, i) ||
+ ARES_GETSOCK_WRITABLE(socks_bitmask, i)) {
+ fd_node* fdn = pop_fd_node_locked(&ev_driver->fds, socks[i]);
+ // Create a new fd_node if sock[i] is not in the fd_node list.
+ if (fdn == nullptr) {
+ fdn = static_cast<fd_node*>(gpr_malloc(sizeof(fd_node)));
+ fdn->grpc_polled_fd = grpc_core::NewGrpcPolledFdLocked(
+ socks[i], ev_driver->pollset_set);
+ gpr_log(GPR_DEBUG, "new fd: %s", fdn->grpc_polled_fd->GetName());
+ fdn->ev_driver = ev_driver;
+ fdn->readable_registered = false;
+ fdn->writable_registered = false;
+ fdn->already_shutdown = false;
+ GRPC_CLOSURE_INIT(&fdn->read_closure, on_readable_locked, fdn,
+ grpc_combiner_scheduler(ev_driver->combiner));
+ GRPC_CLOSURE_INIT(&fdn->write_closure, on_writable_locked, fdn,
+ grpc_combiner_scheduler(ev_driver->combiner));
+ }
+ fdn->next = new_list;
+ new_list = fdn;
+ // Register read_closure if the socket is readable and read_closure has
+ // not been registered with this socket.
+ if (ARES_GETSOCK_READABLE(socks_bitmask, i) &&
+ !fdn->readable_registered) {
+ grpc_ares_ev_driver_ref(ev_driver);
+ gpr_log(GPR_DEBUG, "notify read on: %s",
+ fdn->grpc_polled_fd->GetName());
+ fdn->grpc_polled_fd->RegisterForOnReadableLocked(&fdn->read_closure);
+ fdn->readable_registered = true;
+ }
+ // Register write_closure if the socket is writable and write_closure
+ // has not been registered with this socket.
+ if (ARES_GETSOCK_WRITABLE(socks_bitmask, i) &&
+ !fdn->writable_registered) {
+ gpr_log(GPR_DEBUG, "notify write on: %s",
+ fdn->grpc_polled_fd->GetName());
+ grpc_ares_ev_driver_ref(ev_driver);
+ fdn->grpc_polled_fd->RegisterForOnWriteableLocked(
+ &fdn->write_closure);
+ fdn->writable_registered = true;
+ }
+ }
+ }
+ }
+ // Any remaining fds in ev_driver->fds were not returned by ares_getsock() and
+ // are therefore no longer in use, so they can be shut down and removed from
+ // the list.
+ while (ev_driver->fds != nullptr) {
+ fd_node* cur = ev_driver->fds;
+ ev_driver->fds = ev_driver->fds->next;
+ fd_node_shutdown_locked(cur, "c-ares fd shutdown");
+ if (!cur->readable_registered && !cur->writable_registered) {
+ fd_node_destroy_locked(cur);
+ } else {
+ cur->next = new_list;
+ new_list = cur;
+ }
+ }
+ ev_driver->fds = new_list;
+ // If the ev driver has no working fd, all the tasks are done.
+ if (new_list == nullptr) {
+ ev_driver->working = false;
+ gpr_log(GPR_DEBUG, "ev driver stop working");
+ }
+}
+
+void grpc_ares_ev_driver_start_locked(grpc_ares_ev_driver* ev_driver) {
+ if (!ev_driver->working) {
+ ev_driver->working = true;
+ grpc_ares_notify_on_event_locked(ev_driver);
+ }
+}
+
+#endif /* GRPC_ARES == 1 && defined(GRPC_POSIX_SOCKET_ARES_EV_DRIVER) */
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
index 27d1511..7002c8f 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h
@@ -22,6 +22,7 @@
#include <grpc/support/port_platform.h>
#include <ares.h>
+#include "src/core/lib/gprpp/abstract.h"
#include "src/core/lib/iomgr/pollset_set.h"
typedef struct grpc_ares_ev_driver grpc_ares_ev_driver;
@@ -51,5 +52,40 @@
/* Shutdown all the grpc_fds used by \a ev_driver */
void grpc_ares_ev_driver_shutdown_locked(grpc_ares_ev_driver* ev_driver);
+namespace grpc_core {
+
+/* A wrapped fd that integrates with the grpc iomgr of the current platform.
+ * A GrpcPolledFd knows how to create grpc platform-specific iomgr endpoints
+ * from "ares_socket_t" sockets, and then sign up for readability/writeability
+ * with that poller, and do shutdown and destruction. */
+class GrpcPolledFd {
+ public:
+ virtual ~GrpcPolledFd() {}
+ /* Called when c-ares library is interested and there's no pending callback */
+ virtual void RegisterForOnReadableLocked(grpc_closure* read_closure)
+ GRPC_ABSTRACT;
+ /* Called when c-ares library is interested and there's no pending callback */
+ virtual void RegisterForOnWriteableLocked(grpc_closure* write_closure)
+ GRPC_ABSTRACT;
+ /* Indicates if there is data left even after just being read from */
+ virtual bool IsFdStillReadableLocked() GRPC_ABSTRACT;
+ /* Called once and only once. Must cause cancellation of any pending
+ * read/write callbacks. */
+ virtual void ShutdownLocked(grpc_error* error) GRPC_ABSTRACT;
+ /* Get the underlying ares_socket_t that this was created from */
+ virtual ares_socket_t GetWrappedAresSocketLocked() GRPC_ABSTRACT;
+ /* A unique name, for logging */
+ virtual const char* GetName() GRPC_ABSTRACT;
+
+ GRPC_ABSTRACT_BASE_CLASS
+};
+
+/* Creates a new wrapped fd for the current platform */
+GrpcPolledFd* NewGrpcPolledFdLocked(ares_socket_t as,
+ grpc_pollset_set* driver_pollset_set);
+void ConfigureAresChannelLocked(ares_channel* channel);
+
+} // namespace grpc_core
+
#endif /* GRPC_CORE_EXT_FILTERS_CLIENT_CHANNEL_RESOLVER_DNS_C_ARES_GRPC_ARES_EV_DRIVER_H \
*/
diff --git a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc
index b73e979..5db832b 100644
--- a/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc
+++ b/src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc
@@ -36,286 +36,60 @@
#include "src/core/lib/iomgr/iomgr_internal.h"
#include "src/core/lib/iomgr/sockaddr_utils.h"
-typedef struct fd_node {
- /** the owner of this fd node */
- grpc_ares_ev_driver* ev_driver;
- /** a closure wrapping on_readable_locked, which should be
- invoked when the grpc_fd in this node becomes readable. */
- grpc_closure read_closure;
- /** a closure wrapping on_writable_locked, which should be
- invoked when the grpc_fd in this node becomes writable. */
- grpc_closure write_closure;
- /** next fd node in the list */
- struct fd_node* next;
+namespace grpc_core {
- /** 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 has been shutdown yet from grpc iomgr perspective */
- bool already_shutdown;
-} fd_node;
+class GrpcPolledFdPosix : public GrpcPolledFd {
+ public:
+ GrpcPolledFdPosix(ares_socket_t as, grpc_pollset_set* driver_pollset_set)
+ : as_(as) {
+ gpr_asprintf(&name_, "c-ares fd: %d", (int)as);
+ fd_ = grpc_fd_create((int)as, name_, false);
+ grpc_pollset_set_add_fd(driver_pollset_set, fd_);
+ }
-struct grpc_ares_ev_driver {
- /** the ares_channel owned by this event driver */
- ares_channel channel;
- /** pollset set for driving the IO events of the channel */
- grpc_pollset_set* pollset_set;
- /** refcount of the event driver */
- gpr_refcount refs;
+ ~GrpcPolledFdPosix() {
+ gpr_free(name_);
+ /* c-ares library will close 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. */
+ int dummy_release_fd;
+ grpc_fd_orphan(fd_, nullptr, &dummy_release_fd, "c-ares query finished");
+ }
- /** combiner to synchronize c-ares and I/O callbacks on */
- grpc_combiner* combiner;
- /** a list of grpc_fd that this event driver is currently using. */
- fd_node* fds;
- /** is this event driver currently working? */
- bool working;
- /** is this event driver being shut down */
- bool shutting_down;
+ void RegisterForOnReadableLocked(grpc_closure* read_closure) override {
+ grpc_fd_notify_on_read(fd_, read_closure);
+ }
+
+ void RegisterForOnWriteableLocked(grpc_closure* write_closure) override {
+ grpc_fd_notify_on_write(fd_, write_closure);
+ }
+
+ bool IsFdStillReadableLocked() override {
+ size_t bytes_available = 0;
+ return ioctl(grpc_fd_wrapped_fd(fd_), FIONREAD, &bytes_available) == 0 &&
+ bytes_available > 0;
+ }
+
+ void ShutdownLocked(grpc_error* error) override {
+ grpc_fd_shutdown(fd_, error);
+ }
+
+ ares_socket_t GetWrappedAresSocketLocked() override { return as_; }
+
+ const char* GetName() override { return name_; }
+
+ char* name_;
+ ares_socket_t as_;
+ grpc_fd* fd_;
};
-static void grpc_ares_notify_on_event_locked(grpc_ares_ev_driver* ev_driver);
-
-static grpc_ares_ev_driver* grpc_ares_ev_driver_ref(
- grpc_ares_ev_driver* ev_driver) {
- gpr_log(GPR_DEBUG, "Ref ev_driver %" PRIuPTR, (uintptr_t)ev_driver);
- gpr_ref(&ev_driver->refs);
- return ev_driver;
+GrpcPolledFd* NewGrpcPolledFdLocked(ares_socket_t as,
+ grpc_pollset_set* driver_pollset_set) {
+ return grpc_core::New<GrpcPolledFdPosix>(as, driver_pollset_set);
}
-static void grpc_ares_ev_driver_unref(grpc_ares_ev_driver* ev_driver) {
- gpr_log(GPR_DEBUG, "Unref ev_driver %" PRIuPTR, (uintptr_t)ev_driver);
- if (gpr_unref(&ev_driver->refs)) {
- gpr_log(GPR_DEBUG, "destroy ev_driver %" PRIuPTR, (uintptr_t)ev_driver);
- GPR_ASSERT(ev_driver->fds == nullptr);
- GRPC_COMBINER_UNREF(ev_driver->combiner, "free ares event driver");
- ares_destroy(ev_driver->channel);
- gpr_free(ev_driver);
- }
-}
+void ConfigureAresChannelLocked(ares_channel* channel) {}
-static void fd_node_destroy_locked(fd_node* fdn) {
- gpr_log(GPR_DEBUG, "delete fd: %d", grpc_fd_wrapped_fd(fdn->fd));
- GPR_ASSERT(!fdn->readable_registered);
- GPR_ASSERT(!fdn->writable_registered);
- GPR_ASSERT(fdn->already_shutdown);
- /* c-ares library will close 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. */
- int dummy_release_fd;
- grpc_fd_orphan(fdn->fd, nullptr, &dummy_release_fd, "c-ares query finished");
- gpr_free(fdn);
-}
-
-static void fd_node_shutdown_locked(fd_node* fdn, const char* reason) {
- if (!fdn->already_shutdown) {
- fdn->already_shutdown = true;
- grpc_fd_shutdown(fdn->fd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(reason));
- }
-}
-
-grpc_error* grpc_ares_ev_driver_create_locked(grpc_ares_ev_driver** ev_driver,
- grpc_pollset_set* pollset_set,
- grpc_combiner* combiner) {
- *ev_driver = static_cast<grpc_ares_ev_driver*>(
- gpr_malloc(sizeof(grpc_ares_ev_driver)));
- ares_options opts;
- memset(&opts, 0, sizeof(opts));
- opts.flags |= ARES_FLAG_STAYOPEN;
- int status = ares_init_options(&(*ev_driver)->channel, &opts, ARES_OPT_FLAGS);
- gpr_log(GPR_DEBUG, "grpc_ares_ev_driver_create_locked");
- if (status != ARES_SUCCESS) {
- char* err_msg;
- gpr_asprintf(&err_msg, "Failed to init ares channel. C-ares error: %s",
- ares_strerror(status));
- grpc_error* err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_msg);
- gpr_free(err_msg);
- gpr_free(*ev_driver);
- return err;
- }
- (*ev_driver)->combiner = GRPC_COMBINER_REF(combiner, "ares event driver");
- gpr_ref_init(&(*ev_driver)->refs, 1);
- (*ev_driver)->pollset_set = pollset_set;
- (*ev_driver)->fds = nullptr;
- (*ev_driver)->working = false;
- (*ev_driver)->shutting_down = false;
- return GRPC_ERROR_NONE;
-}
-
-void grpc_ares_ev_driver_destroy_locked(grpc_ares_ev_driver* ev_driver) {
- // We mark the event driver as being shut down. If the event driver
- // is working, grpc_ares_notify_on_event_locked will shut down the
- // fds; if it's not working, there are no fds to shut down.
- ev_driver->shutting_down = true;
- grpc_ares_ev_driver_unref(ev_driver);
-}
-
-void grpc_ares_ev_driver_shutdown_locked(grpc_ares_ev_driver* ev_driver) {
- ev_driver->shutting_down = true;
- fd_node* fn = ev_driver->fds;
- while (fn != nullptr) {
- fd_node_shutdown_locked(fn, "grpc_ares_ev_driver_shutdown");
- fn = fn->next;
- }
-}
-
-// Search fd in the fd_node list head. This is an O(n) search, the max possible
-// value of n is ARES_GETSOCK_MAXNUM (16). n is typically 1 - 2 in our tests.
-static fd_node* pop_fd_node_locked(fd_node** head, int fd) {
- fd_node dummy_head;
- dummy_head.next = *head;
- fd_node* node = &dummy_head;
- while (node->next != nullptr) {
- if (grpc_fd_wrapped_fd(node->next->fd) == fd) {
- fd_node* ret = node->next;
- node->next = node->next->next;
- *head = dummy_head.next;
- return ret;
- }
- node = node->next;
- }
- return nullptr;
-}
-
-/* Check if \a fd is still readable */
-static bool grpc_ares_is_fd_still_readable_locked(
- 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_locked(void* arg, grpc_error* error) {
- fd_node* fdn = static_cast<fd_node*>(arg);
- grpc_ares_ev_driver* ev_driver = fdn->ev_driver;
- const int fd = grpc_fd_wrapped_fd(fdn->fd);
- fdn->readable_registered = false;
- gpr_log(GPR_DEBUG, "readable on %d", fd);
- if (error == GRPC_ERROR_NONE) {
- do {
- ares_process_fd(ev_driver->channel, fd, ARES_SOCKET_BAD);
- } while (grpc_ares_is_fd_still_readable_locked(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
- // by the following ares_cancel() and the on_done callbacks will be invoked
- // with a status of ARES_ECANCELLED. The remaining file descriptors in this
- // ev_driver will be cleaned up in the follwing
- // grpc_ares_notify_on_event_locked().
- ares_cancel(ev_driver->channel);
- }
- grpc_ares_notify_on_event_locked(ev_driver);
- grpc_ares_ev_driver_unref(ev_driver);
-}
-
-static void on_writable_locked(void* arg, grpc_error* error) {
- fd_node* fdn = static_cast<fd_node*>(arg);
- grpc_ares_ev_driver* ev_driver = fdn->ev_driver;
- const int fd = grpc_fd_wrapped_fd(fdn->fd);
- fdn->writable_registered = false;
- gpr_log(GPR_DEBUG, "writable on %d", fd);
- if (error == GRPC_ERROR_NONE) {
- 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
- // by the following ares_cancel() and the on_done callbacks will be invoked
- // with a status of ARES_ECANCELLED. The remaining file descriptors in this
- // ev_driver will be cleaned up in the follwing
- // grpc_ares_notify_on_event_locked().
- ares_cancel(ev_driver->channel);
- }
- grpc_ares_notify_on_event_locked(ev_driver);
- grpc_ares_ev_driver_unref(ev_driver);
-}
-
-ares_channel* grpc_ares_ev_driver_get_channel_locked(
- grpc_ares_ev_driver* ev_driver) {
- return &ev_driver->channel;
-}
-
-// Get the file descriptors used by the ev_driver's ares channel, register
-// driver_closure with these filedescriptors.
-static void grpc_ares_notify_on_event_locked(grpc_ares_ev_driver* ev_driver) {
- fd_node* new_list = nullptr;
- if (!ev_driver->shutting_down) {
- ares_socket_t socks[ARES_GETSOCK_MAXNUM];
- int socks_bitmask =
- ares_getsock(ev_driver->channel, socks, ARES_GETSOCK_MAXNUM);
- for (size_t i = 0; i < ARES_GETSOCK_MAXNUM; i++) {
- if (ARES_GETSOCK_READABLE(socks_bitmask, i) ||
- ARES_GETSOCK_WRITABLE(socks_bitmask, i)) {
- fd_node* fdn = pop_fd_node_locked(&ev_driver->fds, socks[i]);
- // Create a new fd_node if sock[i] is not in the fd_node list.
- if (fdn == nullptr) {
- char* fd_name;
- gpr_asprintf(&fd_name, "ares_ev_driver-%" PRIuPTR, i);
- fdn = static_cast<fd_node*>(gpr_malloc(sizeof(fd_node)));
- gpr_log(GPR_DEBUG, "new fd: %d", socks[i]);
- fdn->fd = grpc_fd_create(socks[i], fd_name, false);
- fdn->ev_driver = ev_driver;
- fdn->readable_registered = false;
- fdn->writable_registered = false;
- fdn->already_shutdown = false;
- GRPC_CLOSURE_INIT(&fdn->read_closure, on_readable_locked, fdn,
- grpc_combiner_scheduler(ev_driver->combiner));
- GRPC_CLOSURE_INIT(&fdn->write_closure, on_writable_locked, fdn,
- grpc_combiner_scheduler(ev_driver->combiner));
- grpc_pollset_set_add_fd(ev_driver->pollset_set, fdn->fd);
- gpr_free(fd_name);
- }
- fdn->next = new_list;
- new_list = fdn;
- // Register read_closure if the socket is readable and read_closure has
- // not been registered with this socket.
- 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->fd));
- grpc_fd_notify_on_read(fdn->fd, &fdn->read_closure);
- fdn->readable_registered = true;
- }
- // Register write_closure if the socket is writable and write_closure
- // has not been registered with this socket.
- if (ARES_GETSOCK_WRITABLE(socks_bitmask, i) &&
- !fdn->writable_registered) {
- gpr_log(GPR_DEBUG, "notify write on: %d",
- grpc_fd_wrapped_fd(fdn->fd));
- grpc_ares_ev_driver_ref(ev_driver);
- grpc_fd_notify_on_write(fdn->fd, &fdn->write_closure);
- fdn->writable_registered = true;
- }
- }
- }
- }
- // Any remaining fds in ev_driver->fds were not returned by ares_getsock() and
- // are therefore no longer in use, so they can be shut down and removed from
- // the list.
- while (ev_driver->fds != nullptr) {
- fd_node* cur = ev_driver->fds;
- ev_driver->fds = ev_driver->fds->next;
- fd_node_shutdown_locked(cur, "c-ares fd shutdown");
- if (!cur->readable_registered && !cur->writable_registered) {
- fd_node_destroy_locked(cur);
- } else {
- cur->next = new_list;
- new_list = cur;
- }
- }
- ev_driver->fds = new_list;
- // If the ev driver has no working fd, all the tasks are done.
- if (new_list == nullptr) {
- ev_driver->working = false;
- gpr_log(GPR_DEBUG, "ev driver stop working");
- }
-}
-
-void grpc_ares_ev_driver_start_locked(grpc_ares_ev_driver* ev_driver) {
- if (!ev_driver->working) {
- ev_driver->working = true;
- grpc_ares_notify_on_event_locked(ev_driver);
- }
-}
+} // namespace grpc_core
#endif /* GRPC_ARES == 1 && defined(GRPC_POSIX_SOCKET_ARES_EV_DRIVER) */
diff --git a/src/python/grpcio/grpc_core_dependencies.py b/src/python/grpcio/grpc_core_dependencies.py
index 5511bf9..d7d489c 100644
--- a/src/python/grpcio/grpc_core_dependencies.py
+++ b/src/python/grpcio/grpc_core_dependencies.py
@@ -345,6 +345,7 @@
'src/core/ext/filters/client_channel/lb_policy/pick_first/pick_first.cc',
'src/core/ext/filters/client_channel/lb_policy/round_robin/round_robin.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc',
+ 'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc',
'src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper_fallback.cc',
diff --git a/tools/doxygen/Doxyfile.core.internal b/tools/doxygen/Doxyfile.core.internal
index 589e862..478c417 100644
--- a/tools/doxygen/Doxyfile.core.internal
+++ b/tools/doxygen/Doxyfile.core.internal
@@ -913,6 +913,7 @@
src/core/ext/filters/client_channel/resolver.h \
src/core/ext/filters/client_channel/resolver/README.md \
src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc \
+src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc \
src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc \
diff --git a/tools/run_tests/generated/sources_and_headers.json b/tools/run_tests/generated/sources_and_headers.json
index 4b5f7d5..413efa5 100644
--- a/tools/run_tests/generated/sources_and_headers.json
+++ b/tools/run_tests/generated/sources_and_headers.json
@@ -10136,6 +10136,7 @@
"name": "grpc_resolver_dns_ares",
"src": [
"src/core/ext/filters/client_channel/resolver/dns/c_ares/dns_resolver_ares.cc",
+ "src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.cc",
"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver.h",
"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_ev_driver_posix.cc",
"src/core/ext/filters/client_channel/resolver/dns/c_ares/grpc_ares_wrapper.cc",
