Changes for C to C++. Adding extern C to header files for compatibility.

Also converting to .cc

1 files changed, 249 insertions, 0 deletions

diff --git a/src/core/ext/filters/client_channel/channel_connectivity.cc b/src/core/ext/filters/client_channel/channel_connectivity.cc
new file mode 100644
index 0000000000..3844b98021
--- /dev/null
+++ b/src/core/ext/filters/client_channel/channel_connectivity.cc
@@ -0,0 +1,249 @@
+/*
+ *
+ * Copyright 2015 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 "src/core/lib/surface/channel.h"
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+
+#include "src/core/ext/filters/client_channel/client_channel.h"
+#include "src/core/lib/iomgr/timer.h"
+#include "src/core/lib/surface/api_trace.h"
+#include "src/core/lib/surface/completion_queue.h"
+
+grpc_connectivity_state grpc_channel_check_connectivity_state(
+    grpc_channel *channel, int try_to_connect) {
+  /* forward through to the underlying client channel */
+  grpc_channel_element *client_channel_elem =
+      grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  grpc_connectivity_state state;
+  GRPC_API_TRACE(
+      "grpc_channel_check_connectivity_state(channel=%p, try_to_connect=%d)", 2,
+      (channel, try_to_connect));
+  if (client_channel_elem->filter == &grpc_client_channel_filter) {
+    state = grpc_client_channel_check_connectivity_state(
+        &exec_ctx, client_channel_elem, try_to_connect);
+    grpc_exec_ctx_finish(&exec_ctx);
+    return state;
+  }
+  gpr_log(GPR_ERROR,
+          "grpc_channel_check_connectivity_state called on something that is "
+          "not a client channel, but '%s'",
+          client_channel_elem->filter->name);
+  grpc_exec_ctx_finish(&exec_ctx);
+  return GRPC_CHANNEL_SHUTDOWN;
+}
+
+typedef enum {
+  WAITING,
+  READY_TO_CALL_BACK,
+  CALLING_BACK_AND_FINISHED,
+} callback_phase;
+
+typedef struct {
+  gpr_mu mu;
+  callback_phase phase;
+  grpc_closure on_complete;
+  grpc_closure on_timeout;
+  grpc_closure watcher_timer_init;
+  grpc_timer alarm;
+  grpc_connectivity_state state;
+  grpc_completion_queue *cq;
+  grpc_cq_completion completion_storage;
+  grpc_channel *channel;
+  grpc_error *error;
+  void *tag;
+} state_watcher;
+
+static void delete_state_watcher(grpc_exec_ctx *exec_ctx, state_watcher *w) {
+  grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
+      grpc_channel_get_channel_stack(w->channel));
+  if (client_channel_elem->filter == &grpc_client_channel_filter) {
+    GRPC_CHANNEL_INTERNAL_UNREF(exec_ctx, w->channel,
+                                "watch_channel_connectivity");
+  } else {
+    abort();
+  }
+  gpr_mu_destroy(&w->mu);
+  gpr_free(w);
+}
+
+static void finished_completion(grpc_exec_ctx *exec_ctx, void *pw,
+                                grpc_cq_completion *ignored) {
+  bool should_delete = false;
+  state_watcher *w = (state_watcher *)pw;
+  gpr_mu_lock(&w->mu);
+  switch (w->phase) {
+    case WAITING:
+    case READY_TO_CALL_BACK:
+      GPR_UNREACHABLE_CODE(return );
+    case CALLING_BACK_AND_FINISHED:
+      should_delete = true;
+      break;
+  }
+  gpr_mu_unlock(&w->mu);
+
+  if (should_delete) {
+    delete_state_watcher(exec_ctx, w);
+  }
+}
+
+static void partly_done(grpc_exec_ctx *exec_ctx, state_watcher *w,
+                        bool due_to_completion, grpc_error *error) {
+  if (due_to_completion) {
+    grpc_timer_cancel(exec_ctx, &w->alarm);
+  } else {
+    grpc_channel_element *client_channel_elem = grpc_channel_stack_last_element(
+        grpc_channel_get_channel_stack(w->channel));
+    grpc_client_channel_watch_connectivity_state(
+        exec_ctx, client_channel_elem,
+        grpc_polling_entity_create_from_pollset(grpc_cq_pollset(w->cq)), NULL,
+        &w->on_complete, NULL);
+  }
+
+  gpr_mu_lock(&w->mu);
+
+  if (due_to_completion) {
+    if (GRPC_TRACER_ON(grpc_trace_operation_failures)) {
+      GRPC_LOG_IF_ERROR("watch_completion_error", GRPC_ERROR_REF(error));
+    }
+    GRPC_ERROR_UNREF(error);
+    error = GRPC_ERROR_NONE;
+  } else {
+    if (error == GRPC_ERROR_NONE) {
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "Timed out waiting for connection state change");
+    } else if (error == GRPC_ERROR_CANCELLED) {
+      error = GRPC_ERROR_NONE;
+    }
+  }
+  switch (w->phase) {
+    case WAITING:
+      GRPC_ERROR_REF(error);
+      w->error = error;
+      w->phase = READY_TO_CALL_BACK;
+      break;
+    case READY_TO_CALL_BACK:
+      if (error != GRPC_ERROR_NONE) {
+        GPR_ASSERT(!due_to_completion);
+        GRPC_ERROR_UNREF(w->error);
+        GRPC_ERROR_REF(error);
+        w->error = error;
+      }
+      w->phase = CALLING_BACK_AND_FINISHED;
+      grpc_cq_end_op(exec_ctx, w->cq, w->tag, w->error, finished_completion, w,
+                     &w->completion_storage);
+      break;
+    case CALLING_BACK_AND_FINISHED:
+      GPR_UNREACHABLE_CODE(return );
+      break;
+  }
+  gpr_mu_unlock(&w->mu);
+
+  GRPC_ERROR_UNREF(error);
+}
+
+static void watch_complete(grpc_exec_ctx *exec_ctx, void *pw,
+                           grpc_error *error) {
+  partly_done(exec_ctx, (state_watcher *)pw, true, GRPC_ERROR_REF(error));
+}
+
+static void timeout_complete(grpc_exec_ctx *exec_ctx, void *pw,
+                             grpc_error *error) {
+  partly_done(exec_ctx, (state_watcher *)pw, false, GRPC_ERROR_REF(error));
+}
+
+int grpc_channel_num_external_connectivity_watchers(grpc_channel *channel) {
+  grpc_channel_element *client_channel_elem =
+      grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
+  return grpc_client_channel_num_external_connectivity_watchers(
+      client_channel_elem);
+}
+
+typedef struct watcher_timer_init_arg {
+  state_watcher *w;
+  gpr_timespec deadline;
+} watcher_timer_init_arg;
+
+static void watcher_timer_init(grpc_exec_ctx *exec_ctx, void *arg,
+                               grpc_error *error_ignored) {
+  watcher_timer_init_arg *wa = (watcher_timer_init_arg *)arg;
+
+  grpc_timer_init(exec_ctx, &wa->w->alarm,
+                  gpr_convert_clock_type(wa->deadline, GPR_CLOCK_MONOTONIC),
+                  &wa->w->on_timeout, gpr_now(GPR_CLOCK_MONOTONIC));
+  gpr_free(wa);
+}
+
+int grpc_channel_support_connectivity_watcher(grpc_channel *channel) {
+  grpc_channel_element *client_channel_elem =
+      grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
+  return client_channel_elem->filter != &grpc_client_channel_filter ? 0 : 1;
+}
+
+void grpc_channel_watch_connectivity_state(
+    grpc_channel *channel, grpc_connectivity_state last_observed_state,
+    gpr_timespec deadline, grpc_completion_queue *cq, void *tag) {
+  grpc_channel_element *client_channel_elem =
+      grpc_channel_stack_last_element(grpc_channel_get_channel_stack(channel));
+  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
+  state_watcher *w = (state_watcher *)gpr_malloc(sizeof(*w));
+
+  GRPC_API_TRACE(
+      "grpc_channel_watch_connectivity_state("
+      "channel=%p, last_observed_state=%d, "
+      "deadline=gpr_timespec { tv_sec: %" PRId64
+      ", tv_nsec: %d, clock_type: %d }, "
+      "cq=%p, tag=%p)",
+      7, (channel, (int)last_observed_state, deadline.tv_sec, deadline.tv_nsec,
+          (int)deadline.clock_type, cq, tag));
+
+  GPR_ASSERT(grpc_cq_begin_op(cq, tag));
+
+  gpr_mu_init(&w->mu);
+  GRPC_CLOSURE_INIT(&w->on_complete, watch_complete, w,
+                    grpc_schedule_on_exec_ctx);
+  GRPC_CLOSURE_INIT(&w->on_timeout, timeout_complete, w,
+                    grpc_schedule_on_exec_ctx);
+  w->phase = WAITING;
+  w->state = last_observed_state;
+  w->cq = cq;
+  w->tag = tag;
+  w->channel = channel;
+  w->error = NULL;
+
+  watcher_timer_init_arg *wa =
+      (watcher_timer_init_arg *)gpr_malloc(sizeof(watcher_timer_init_arg));
+  wa->w = w;
+  wa->deadline = deadline;
+  GRPC_CLOSURE_INIT(&w->watcher_timer_init, watcher_timer_init, wa,
+                    grpc_schedule_on_exec_ctx);
+
+  if (client_channel_elem->filter == &grpc_client_channel_filter) {
+    GRPC_CHANNEL_INTERNAL_REF(channel, "watch_channel_connectivity");
+    grpc_client_channel_watch_connectivity_state(
+        &exec_ctx, client_channel_elem,
+        grpc_polling_entity_create_from_pollset(grpc_cq_pollset(cq)), &w->state,
+        &w->on_complete, &w->watcher_timer_init);
+  } else {
+    abort();
+  }
+
+  grpc_exec_ctx_finish(&exec_ctx);
+}