Initial checkin of gRPC to third_party/

third_party/grpc/src/core/channel/connected_channel.c

Index: third_party/grpc/src/core/channel/connected_channel.c
diff --git a/third_party/grpc/src/core/channel/connected_channel.c b/third_party/grpc/src/core/channel/connected_channel.c
new file mode 100644
index 0000000000000000000000000000000000000000..e8eb9dcfc5cb2f78953ab04bf875366f8b389d91
--- /dev/null
+++ b/third_party/grpc/src/core/channel/connected_channel.c
@@ -0,0 +1,167 @@
+/*
+ *
+ * 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/channel/connected_channel.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "src/core/support/string.h"
+#include "src/core/transport/transport.h"
+#include "src/core/profiling/timers.h"
+#include <grpc/byte_buffer.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/log.h>
+#include <grpc/support/slice_buffer.h>
+
+#define MAX_BUFFER_LENGTH 8192
+
+typedef struct connected_channel_channel_data {
+  grpc_transport *transport;
+} channel_data;
+
+typedef struct connected_channel_call_data { void *unused; } call_data;
+
+/* We perform a small hack to locate transport data alongside the connected
+   channel data in call allocations, to allow everything to be pulled in minimal
+   cache line requests */
+#define TRANSPORT_STREAM_FROM_CALL_DATA(calld) ((grpc_stream *)((calld) + 1))
+#define CALL_DATA_FROM_TRANSPORT_STREAM(transport_stream) \
+  (((call_data *)(transport_stream)) - 1)
+
+/* Intercept a call operation and either push it directly up or translate it
+   into transport stream operations */
+static void con_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
+                                          grpc_call_element *elem,
+                                          grpc_transport_stream_op *op) {
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
+  GRPC_CALL_LOG_OP(GPR_INFO, elem, op);
+
+  grpc_transport_perform_stream_op(exec_ctx, chand->transport,
+                                   TRANSPORT_STREAM_FROM_CALL_DATA(calld), op);
+}
+
+static void con_start_transport_op(grpc_exec_ctx *exec_ctx,
+                                   grpc_channel_element *elem,
+                                   grpc_transport_op *op) {
+  channel_data *chand = elem->channel_data;
+  grpc_transport_perform_op(exec_ctx, chand->transport, op);
+}
+
+/* Constructor for call_data */
+static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                           grpc_call_element_args *args) {
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  int r;
+
+  GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
+  r = grpc_transport_init_stream(
+      exec_ctx, chand->transport, TRANSPORT_STREAM_FROM_CALL_DATA(calld),
+      &args->call_stack->refcount, args->server_transport_data);
+  GPR_ASSERT(r == 0);
+}
+
+static void set_pollset(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                        grpc_pollset *pollset) {
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  grpc_transport_set_pollset(exec_ctx, chand->transport,
+                             TRANSPORT_STREAM_FROM_CALL_DATA(calld), pollset);
+}
+
+/* Destructor for call_data */
+static void destroy_call_elem(grpc_exec_ctx *exec_ctx,
+                              grpc_call_element *elem) {
+  call_data *calld = elem->call_data;
+  channel_data *chand = elem->channel_data;
+  GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
+  grpc_transport_destroy_stream(exec_ctx, chand->transport,
+                                TRANSPORT_STREAM_FROM_CALL_DATA(calld));
+}
+
+/* Constructor for channel_data */
+static void init_channel_elem(grpc_exec_ctx *exec_ctx,
+                              grpc_channel_element *elem,
+                              grpc_channel_element_args *args) {
+  channel_data *cd = (channel_data *)elem->channel_data;
+  GPR_ASSERT(args->is_last);
+  GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
+  cd->transport = NULL;
+}
+
+/* Destructor for channel_data */
+static void destroy_channel_elem(grpc_exec_ctx *exec_ctx,
+                                 grpc_channel_element *elem) {
+  channel_data *cd = (channel_data *)elem->channel_data;
+  GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
+  grpc_transport_destroy(exec_ctx, cd->transport);
+}
+
+static char *con_get_peer(grpc_exec_ctx *exec_ctx, grpc_call_element *elem) {
+  channel_data *chand = elem->channel_data;
+  return grpc_transport_get_peer(exec_ctx, chand->transport);
+}
+
+const grpc_channel_filter grpc_connected_channel_filter = {
+    con_start_transport_stream_op, con_start_transport_op, sizeof(call_data),
+    init_call_elem, set_pollset, destroy_call_elem, sizeof(channel_data),
+    init_channel_elem, destroy_channel_elem, con_get_peer, "connected",
+};
+
+void grpc_connected_channel_bind_transport(grpc_channel_stack *channel_stack,
+                                           grpc_transport *transport) {
+  /* Assumes that the connected channel filter is always the last filter
+     in a channel stack */
+  grpc_channel_element *elem = grpc_channel_stack_last_element(channel_stack);
+  channel_data *cd = (channel_data *)elem->channel_data;
+  GPR_ASSERT(elem->filter == &grpc_connected_channel_filter);
+  GPR_ASSERT(cd->transport == NULL);
+  cd->transport = transport;
+
+  /* HACK(ctiller): increase call stack size for the channel to make space
+     for channel data. We need a cleaner (but performant) way to do this,
+     and I'm not sure what that is yet.
+     This is only "safe" because call stacks place no additional data after
+     the last call element, and the last call element MUST be the connected
+     channel. */
+  channel_stack->call_stack_size += grpc_transport_stream_size(transport);
+}
+
+grpc_stream *grpc_connected_channel_get_stream(grpc_call_element *elem) {
+  call_data *calld = elem->call_data;
+  return TRANSPORT_STREAM_FROM_CALL_DATA(calld);
+}