Initial checkin of gRPC to third_party/

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

Index: third_party/grpc/src/core/channel/channel_stack.c
diff --git a/third_party/grpc/src/core/channel/channel_stack.c b/third_party/grpc/src/core/channel/channel_stack.c
new file mode 100644
index 0000000000000000000000000000000000000000..3e616883640d1f91428aefbde37e3b397aaef122
--- /dev/null
+++ b/third_party/grpc/src/core/channel/channel_stack.c
@@ -0,0 +1,262 @@
+/*
+ *
+ * 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/channel_stack.h"
+#include <grpc/support/log.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+int grpc_trace_channel = 0;
+
+/* Memory layouts.
+
+   Channel stack is laid out as: {
+     grpc_channel_stack stk;
+     padding to GPR_MAX_ALIGNMENT
+     grpc_channel_element[stk.count];
+     per-filter memory, aligned to GPR_MAX_ALIGNMENT
+   }
+
+   Call stack is laid out as: {
+     grpc_call_stack stk;
+     padding to GPR_MAX_ALIGNMENT
+     grpc_call_element[stk.count];
+     per-filter memory, aligned to GPR_MAX_ALIGNMENT
+   } */
+
+/* Given a size, round up to the next multiple of sizeof(void*) */
+#define ROUND_UP_TO_ALIGNMENT_SIZE(x) \
+  (((x) + GPR_MAX_ALIGNMENT - 1u) & ~(GPR_MAX_ALIGNMENT - 1u))
+
+size_t grpc_channel_stack_size(const grpc_channel_filter **filters,
+                               size_t filter_count) {
+  /* always need the header, and size for the channel elements */
+  size_t size =
+      ROUND_UP_TO_ALIGNMENT_SIZE(sizeof(grpc_channel_stack)) +
+      ROUND_UP_TO_ALIGNMENT_SIZE(filter_count * sizeof(grpc_channel_element));
+  size_t i;
+
+  GPR_ASSERT((GPR_MAX_ALIGNMENT & (GPR_MAX_ALIGNMENT - 1)) == 0 &&
+             "GPR_MAX_ALIGNMENT must be a power of two");
+
+  /* add the size for each filter */
+  for (i = 0; i < filter_count; i++) {
+    size += ROUND_UP_TO_ALIGNMENT_SIZE(filters[i]->sizeof_channel_data);
+  }
+
+  return size;
+}
+
+#define CHANNEL_ELEMS_FROM_STACK(stk)                                   \
+  ((grpc_channel_element *)((char *)(stk) + ROUND_UP_TO_ALIGNMENT_SIZE( \
+                                                sizeof(grpc_channel_stack))))
+
+#define CALL_ELEMS_FROM_STACK(stk)       \
+  ((grpc_call_element *)((char *)(stk) + \
+                         ROUND_UP_TO_ALIGNMENT_SIZE(sizeof(grpc_call_stack))))
+
+grpc_channel_element *grpc_channel_stack_element(
+    grpc_channel_stack *channel_stack, size_t index) {
+  return CHANNEL_ELEMS_FROM_STACK(channel_stack) + index;
+}
+
+grpc_channel_element *grpc_channel_stack_last_element(
+    grpc_channel_stack *channel_stack) {
+  return grpc_channel_stack_element(channel_stack, channel_stack->count - 1);
+}
+
+grpc_call_element *grpc_call_stack_element(grpc_call_stack *call_stack,
+                                           size_t index) {
+  return CALL_ELEMS_FROM_STACK(call_stack) + index;
+}
+
+void grpc_channel_stack_init(grpc_exec_ctx *exec_ctx, int initial_refs,
+                             grpc_iomgr_cb_func destroy, void *destroy_arg,
+                             const grpc_channel_filter **filters,
+                             size_t filter_count,
+                             const grpc_channel_args *channel_args,
+                             const char *name, grpc_channel_stack *stack) {
+  size_t call_size =
+      ROUND_UP_TO_ALIGNMENT_SIZE(sizeof(grpc_call_stack)) +
+      ROUND_UP_TO_ALIGNMENT_SIZE(filter_count * sizeof(grpc_call_element));
+  grpc_channel_element *elems;
+  grpc_channel_element_args args;
+  char *user_data;
+  size_t i;
+
+  stack->count = filter_count;
+  GRPC_STREAM_REF_INIT(&stack->refcount, initial_refs, destroy, destroy_arg,
+                       name);
+  elems = CHANNEL_ELEMS_FROM_STACK(stack);
+  user_data =
+      ((char *)elems) +
+      ROUND_UP_TO_ALIGNMENT_SIZE(filter_count * sizeof(grpc_channel_element));
+
+  /* init per-filter data */
+  for (i = 0; i < filter_count; i++) {
+    args.channel_stack = stack;
+    args.channel_args = channel_args;
+    args.is_first = i == 0;
+    args.is_last = i == (filter_count - 1);
+    elems[i].filter = filters[i];
+    elems[i].channel_data = user_data;
+    elems[i].filter->init_channel_elem(exec_ctx, &elems[i], &args);
+    user_data += ROUND_UP_TO_ALIGNMENT_SIZE(filters[i]->sizeof_channel_data);
+    call_size += ROUND_UP_TO_ALIGNMENT_SIZE(filters[i]->sizeof_call_data);
+  }
+
+  GPR_ASSERT(user_data > (char *)stack);
+  GPR_ASSERT((uintptr_t)(user_data - (char *)stack) ==
+             grpc_channel_stack_size(filters, filter_count));
+
+  stack->call_stack_size = call_size;
+}
+
+void grpc_channel_stack_destroy(grpc_exec_ctx *exec_ctx,
+                                grpc_channel_stack *stack) {
+  grpc_channel_element *channel_elems = CHANNEL_ELEMS_FROM_STACK(stack);
+  size_t count = stack->count;
+  size_t i;
+
+  /* destroy per-filter data */
+  for (i = 0; i < count; i++) {
+    channel_elems[i].filter->destroy_channel_elem(exec_ctx, &channel_elems[i]);
+  }
+}
+
+void grpc_call_stack_init(grpc_exec_ctx *exec_ctx,
+                          grpc_channel_stack *channel_stack, int initial_refs,
+                          grpc_iomgr_cb_func destroy, void *destroy_arg,
+                          grpc_call_context_element *context,
+                          const void *transport_server_data,
+                          grpc_call_stack *call_stack) {
+  grpc_channel_element *channel_elems = CHANNEL_ELEMS_FROM_STACK(channel_stack);
+  grpc_call_element_args args;
+  size_t count = channel_stack->count;
+  grpc_call_element *call_elems;
+  char *user_data;
+  size_t i;
+
+  call_stack->count = count;
+  GRPC_STREAM_REF_INIT(&call_stack->refcount, initial_refs, destroy,
+                       destroy_arg, "CALL_STACK");
+  call_elems = CALL_ELEMS_FROM_STACK(call_stack);
+  user_data = ((char *)call_elems) +
+              ROUND_UP_TO_ALIGNMENT_SIZE(count * sizeof(grpc_call_element));
+
+  /* init per-filter data */
+  for (i = 0; i < count; i++) {
+    args.call_stack = call_stack;
+    args.server_transport_data = transport_server_data;
+    args.context = context;
+    call_elems[i].filter = channel_elems[i].filter;
+    call_elems[i].channel_data = channel_elems[i].channel_data;
+    call_elems[i].call_data = user_data;
+    call_elems[i].filter->init_call_elem(exec_ctx, &call_elems[i], &args);
+    user_data +=
+        ROUND_UP_TO_ALIGNMENT_SIZE(call_elems[i].filter->sizeof_call_data);
+  }
+}
+
+void grpc_call_stack_set_pollset(grpc_exec_ctx *exec_ctx,
+                                 grpc_call_stack *call_stack,
+                                 grpc_pollset *pollset) {
+  size_t count = call_stack->count;
+  grpc_call_element *call_elems;
+  char *user_data;
+  size_t i;
+
+  call_elems = CALL_ELEMS_FROM_STACK(call_stack);
+  user_data = ((char *)call_elems) +
+              ROUND_UP_TO_ALIGNMENT_SIZE(count * sizeof(grpc_call_element));
+
+  /* init per-filter data */
+  for (i = 0; i < count; i++) {
+    call_elems[i].filter->set_pollset(exec_ctx, &call_elems[i], pollset);
+    user_data +=
+        ROUND_UP_TO_ALIGNMENT_SIZE(call_elems[i].filter->sizeof_call_data);
+  }
+}
+
+void grpc_call_stack_ignore_set_pollset(grpc_exec_ctx *exec_ctx,
+                                        grpc_call_element *elem,
+                                        grpc_pollset *pollset) {}
+
+void grpc_call_stack_destroy(grpc_exec_ctx *exec_ctx, grpc_call_stack *stack) {
+  grpc_call_element *elems = CALL_ELEMS_FROM_STACK(stack);
+  size_t count = stack->count;
+  size_t i;
+
+  /* destroy per-filter data */
+  for (i = 0; i < count; i++) {
+    elems[i].filter->destroy_call_elem(exec_ctx, &elems[i]);
+  }
+}
+
+void grpc_call_next_op(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
+                       grpc_transport_stream_op *op) {
+  grpc_call_element *next_elem = elem + 1;
+  next_elem->filter->start_transport_stream_op(exec_ctx, next_elem, op);
+}
+
+char *grpc_call_next_get_peer(grpc_exec_ctx *exec_ctx,
+                              grpc_call_element *elem) {
+  grpc_call_element *next_elem = elem + 1;
+  return next_elem->filter->get_peer(exec_ctx, next_elem);
+}
+
+void grpc_channel_next_op(grpc_exec_ctx *exec_ctx, grpc_channel_element *elem,
+                          grpc_transport_op *op) {
+  grpc_channel_element *next_elem = elem + 1;
+  next_elem->filter->start_transport_op(exec_ctx, next_elem, op);
+}
+
+grpc_channel_stack *grpc_channel_stack_from_top_element(
+    grpc_channel_element *elem) {
+  return (grpc_channel_stack *)((char *)(elem)-ROUND_UP_TO_ALIGNMENT_SIZE(
+      sizeof(grpc_channel_stack)));
+}
+
+grpc_call_stack *grpc_call_stack_from_top_element(grpc_call_element *elem) {
+  return (grpc_call_stack *)((char *)(elem)-ROUND_UP_TO_ALIGNMENT_SIZE(
+      sizeof(grpc_call_stack)));
+}
+
+void grpc_call_element_send_cancel(grpc_exec_ctx *exec_ctx,
+                                   grpc_call_element *cur_elem) {
+  grpc_transport_stream_op op;
+  memset(&op, 0, sizeof(op));
+  op.cancel_with_status = GRPC_STATUS_CANCELLED;
+  grpc_call_next_op(exec_ctx, cur_elem, &op);
+}