diff options
Diffstat (limited to 'src/core/ext/filters/client_channel/channel_connectivity.c')
| -rw-r--r-- | src/core/ext/filters/client_channel/channel_connectivity.c | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/src/core/ext/filters/client_channel/channel_connectivity.c b/src/core/ext/filters/client_channel/channel_connectivity.c new file mode 100644 index 0000000000..62f58fb278 --- /dev/null +++ b/src/core/ext/filters/client_channel/channel_connectivity.c @@ -0,0 +1,226 @@ +/* + * + * Copyright 2015, 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 "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, + CALLING_BACK, + CALLING_BACK_AND_FINISHED, + CALLED_BACK +} callback_phase; + +typedef struct { + gpr_mu mu; + callback_phase phase; + grpc_closure on_complete; + grpc_closure on_timeout; + grpc_timer alarm; + grpc_connectivity_state state; + grpc_completion_queue *cq; + grpc_cq_completion completion_storage; + grpc_channel *channel; + 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) { + int delete = 0; + state_watcher *w = pw; + gpr_mu_lock(&w->mu); + switch (w->phase) { + case WAITING: + case CALLED_BACK: + GPR_UNREACHABLE_CODE(return ); + case CALLING_BACK: + w->phase = CALLED_BACK; + break; + case CALLING_BACK_AND_FINISHED: + delete = 1; + break; + } + gpr_mu_unlock(&w->mu); + + if (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) { + int delete = 0; + + if (due_to_completion) { + grpc_timer_cancel(exec_ctx, &w->alarm); + } + + gpr_mu_lock(&w->mu); + + if (due_to_completion) { + if (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: + w->phase = CALLING_BACK; + grpc_cq_end_op(exec_ctx, w->cq, w->tag, GRPC_ERROR_REF(error), + finished_completion, w, &w->completion_storage); + break; + case CALLING_BACK: + w->phase = CALLING_BACK_AND_FINISHED; + break; + case CALLING_BACK_AND_FINISHED: + GPR_UNREACHABLE_CODE(return ); + case CALLED_BACK: + delete = 1; + break; + } + gpr_mu_unlock(&w->mu); + + if (delete) { + delete_state_watcher(exec_ctx, w); + } + + GRPC_ERROR_UNREF(error); +} + +static void watch_complete(grpc_exec_ctx *exec_ctx, void *pw, + grpc_error *error) { + partly_done(exec_ctx, pw, true, GRPC_ERROR_REF(error)); +} + +static void timeout_complete(grpc_exec_ctx *exec_ctx, void *pw, + grpc_error *error) { + partly_done(exec_ctx, pw, false, GRPC_ERROR_REF(error)); +} + +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 = 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)); + + 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; + + grpc_timer_init(&exec_ctx, &w->alarm, + gpr_convert_clock_type(deadline, GPR_CLOCK_MONOTONIC), + &w->on_timeout, gpr_now(GPR_CLOCK_MONOTONIC)); + + 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_cq_pollset(cq), &w->state, + &w->on_complete); + } else { + abort(); + } + + grpc_exec_ctx_finish(&exec_ctx); +} |