Merge branch 'master' into packet-coalescing-core

18 files changed, 231 insertions, 154 deletions

diff --git a/src/core/ext/census/tracing.c b/src/core/ext/census/tracing.c
index 3b5d6dab2b..9371fffc8d 100644
--- a/src/core/ext/census/tracing.c
+++ b/src/core/ext/census/tracing.c
@@ -31,15 +31,21 @@
  *
  */
 
+//#include "src/core/ext/census/tracing.h"
+
 #include <grpc/census.h>
+#include <stdlib.h>
 
 /* TODO(aveitch): These are all placeholder implementations. */
 
 int census_trace_mask(const census_context *context) {
+  abort();
   return CENSUS_TRACE_MASK_NONE;
 }
 
-void census_set_trace_mask(int trace_mask) {}
+void census_set_trace_mask(int trace_mask) { abort(); }
 
 void census_trace_print(census_context *context, uint32_t type,
-                        const char *buffer, size_t n) {}
+                        const char *buffer, size_t n) {
+  abort();
+}
diff --git a/src/core/ext/client_channel/connector.h b/src/core/ext/client_channel/connector.h
index 3de061620e..395f89b3b2 100644
--- a/src/core/ext/client_channel/connector.h
+++ b/src/core/ext/client_channel/connector.h
@@ -48,9 +48,6 @@ struct grpc_connector {
 typedef struct {
   /** set of pollsets interested in this connection */
   grpc_pollset_set *interested_parties;
-  /** address to connect to */
-  const grpc_resolved_address *addr;
-  size_t addr_len;
   /** initial connect string to send */
   grpc_slice initial_connect_string;
   /** deadline for connection */
diff --git a/src/core/ext/client_channel/resolver_registry.h b/src/core/ext/client_channel/resolver_registry.h
index 4fb16131db..a4606463eb 100644
--- a/src/core/ext/client_channel/resolver_registry.h
+++ b/src/core/ext/client_channel/resolver_registry.h
@@ -60,7 +60,9 @@ void grpc_register_resolver_type(grpc_resolver_factory *factory);
     return it.
     If a resolver factory was not found, return NULL.
     \a args is a set of channel arguments to be included in the result
-    (typically the set of arguments passed in from the client API). */
+    (typically the set of arguments passed in from the client API).
+    \a pollset_set is used to drive IO in the name resolution process, it
+    should not be NULL. */
 grpc_resolver *grpc_resolver_create(grpc_exec_ctx *exec_ctx, const char *target,
                                     const grpc_channel_args *args,
                                     grpc_pollset_set *pollset_set);
diff --git a/src/core/ext/client_channel/subchannel.c b/src/core/ext/client_channel/subchannel.c
index 1bac82b451..8bd284507d 100644
--- a/src/core/ext/client_channel/subchannel.c
+++ b/src/core/ext/client_channel/subchannel.c
@@ -38,12 +38,16 @@
 
 #include <grpc/support/alloc.h>
 #include <grpc/support/avl.h>
+#include <grpc/support/string_util.h>
 
 #include "src/core/ext/client_channel/client_channel.h"
 #include "src/core/ext/client_channel/initial_connect_string.h"
+#include "src/core/ext/client_channel/parse_address.h"
 #include "src/core/ext/client_channel/subchannel_index.h"
+#include "src/core/ext/client_channel/uri_parser.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
+#include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/iomgr/timer.h"
 #include "src/core/lib/profiling/timers.h"
 #include "src/core/lib/slice/slice_internal.h"
@@ -95,8 +99,6 @@ struct grpc_subchannel {
   size_t num_filters;
   /** channel arguments */
   grpc_channel_args *args;
-  /** address to connect to */
-  grpc_resolved_address *addr;
 
   grpc_subchannel_key *key;
 
@@ -211,7 +213,6 @@ static void subchannel_destroy(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_subchannel *c = arg;
   gpr_free((void *)c->filters);
   grpc_channel_args_destroy(exec_ctx, c->args);
-  gpr_free(c->addr);
   grpc_slice_unref_internal(exec_ctx, c->initial_connect_string);
   grpc_connectivity_state_destroy(exec_ctx, &c->state_tracker);
   grpc_connector_unref(exec_ctx, c->connector);
@@ -327,12 +328,17 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
   } else {
     c->filters = NULL;
   }
-  c->addr = gpr_malloc(sizeof(grpc_resolved_address));
-  if (args->addr->len)
-    memcpy(c->addr, args->addr, sizeof(grpc_resolved_address));
   c->pollset_set = grpc_pollset_set_create();
-  grpc_set_initial_connect_string(&c->addr, &c->initial_connect_string);
-  c->args = grpc_channel_args_copy(args->args);
+  grpc_resolved_address *addr = gpr_malloc(sizeof(*addr));
+  grpc_get_subchannel_address_arg(args->args, addr);
+  grpc_set_initial_connect_string(&addr, &c->initial_connect_string);
+  static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS};
+  grpc_arg new_arg = grpc_create_subchannel_address_arg(addr);
+  gpr_free(addr);
+  c->args = grpc_channel_args_copy_and_add_and_remove(
+      args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &new_arg, 1);
+  gpr_free(new_arg.value.string);
+
   c->root_external_state_watcher.next = c->root_external_state_watcher.prev =
       &c->root_external_state_watcher;
   grpc_closure_init(&c->connected, subchannel_connected, c,
@@ -385,7 +391,6 @@ static void continue_connect_locked(grpc_exec_ctx *exec_ctx,
   grpc_connect_in_args args;
 
   args.interested_parties = c->pollset_set;
-  args.addr = c->addr;
   args.deadline = c->next_attempt;
   args.channel_args = c->args;
   args.initial_connect_string = c->initial_connect_string;
@@ -771,3 +776,37 @@ grpc_call_stack *grpc_subchannel_call_get_call_stack(
     grpc_subchannel_call *subchannel_call) {
   return SUBCHANNEL_CALL_TO_CALL_STACK(subchannel_call);
 }
+
+static void grpc_uri_to_sockaddr(char *uri_str, grpc_resolved_address *addr) {
+  grpc_uri *uri = grpc_uri_parse(uri_str, 0 /* suppress_errors */);
+  GPR_ASSERT(uri != NULL);
+  if (strcmp(uri->scheme, "ipv4") == 0) {
+    GPR_ASSERT(parse_ipv4(uri, addr));
+  } else if (strcmp(uri->scheme, "ipv6") == 0) {
+    GPR_ASSERT(parse_ipv6(uri, addr));
+  } else {
+    GPR_ASSERT(parse_unix(uri, addr));
+  }
+  grpc_uri_destroy(uri);
+}
+
+void grpc_get_subchannel_address_arg(const grpc_channel_args *args,
+                                     grpc_resolved_address *addr) {
+  const grpc_arg *addr_arg =
+      grpc_channel_args_find(args, GRPC_ARG_SUBCHANNEL_ADDRESS);
+  GPR_ASSERT(addr_arg != NULL);  // Should have been set by LB policy.
+  GPR_ASSERT(addr_arg->type == GRPC_ARG_STRING);
+  memset(addr, 0, sizeof(*addr));
+  if (*addr_arg->value.string != '\0') {
+    grpc_uri_to_sockaddr(addr_arg->value.string, addr);
+  }
+}
+
+grpc_arg grpc_create_subchannel_address_arg(const grpc_resolved_address *addr) {
+  grpc_arg new_arg;
+  new_arg.key = GRPC_ARG_SUBCHANNEL_ADDRESS;
+  new_arg.type = GRPC_ARG_STRING;
+  new_arg.value.string =
+      addr->len > 0 ? grpc_sockaddr_to_uri(addr) : gpr_strdup("");
+  return new_arg;
+}
diff --git a/src/core/ext/client_channel/subchannel.h b/src/core/ext/client_channel/subchannel.h
index 24aa9f73dc..684675eb37 100644
--- a/src/core/ext/client_channel/subchannel.h
+++ b/src/core/ext/client_channel/subchannel.h
@@ -40,6 +40,9 @@
 #include "src/core/lib/transport/connectivity_state.h"
 #include "src/core/lib/transport/metadata.h"
 
+// Channel arg containing a grpc_resolved_address to connect to.
+#define GRPC_ARG_SUBCHANNEL_ADDRESS "grpc.subchannel_address"
+
 /** A (sub-)channel that knows how to connect to exactly one target
     address. Provides a target for load balancing. */
 typedef struct grpc_subchannel grpc_subchannel;
@@ -164,8 +167,6 @@ struct grpc_subchannel_args {
   size_t filter_count;
   /** Channel arguments to be supplied to the newly created channel */
   const grpc_channel_args *args;
-  /** Address to connect to */
-  grpc_resolved_address *addr;
 };
 
 /** create a subchannel given a connector */
@@ -173,4 +174,12 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
                                         grpc_connector *connector,
                                         const grpc_subchannel_args *args);
 
+/// Sets \a addr from \a args.
+void grpc_get_subchannel_address_arg(const grpc_channel_args *args,
+                                     grpc_resolved_address *addr);
+
+/// Returns a new channel arg encoding the subchannel address as a string.
+/// Caller is responsible for freeing the string.
+grpc_arg grpc_create_subchannel_address_arg(const grpc_resolved_address *addr);
+
 #endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_SUBCHANNEL_H */
diff --git a/src/core/ext/client_channel/subchannel_index.c b/src/core/ext/client_channel/subchannel_index.c
index 1ebe03ef11..11889300a2 100644
--- a/src/core/ext/client_channel/subchannel_index.c
+++ b/src/core/ext/client_channel/subchannel_index.c
@@ -86,11 +86,6 @@ static grpc_subchannel_key *create_key(
   } else {
     k->args.filters = NULL;
   }
-  k->args.addr = gpr_malloc(sizeof(grpc_resolved_address));
-  k->args.addr->len = args->addr->len;
-  if (k->args.addr->len > 0) {
-    memcpy(k->args.addr, args->addr, sizeof(grpc_resolved_address));
-  }
   k->args.args = copy_channel_args(args->args);
   return k;
 }
@@ -108,14 +103,8 @@ static int subchannel_key_compare(grpc_subchannel_key *a,
                                   grpc_subchannel_key *b) {
   int c = GPR_ICMP(a->connector, b->connector);
   if (c != 0) return c;
-  c = GPR_ICMP(a->args.addr->len, b->args.addr->len);
-  if (c != 0) return c;
   c = GPR_ICMP(a->args.filter_count, b->args.filter_count);
   if (c != 0) return c;
-  if (a->args.addr->len) {
-    c = memcmp(a->args.addr->addr, b->args.addr->addr, a->args.addr->len);
-    if (c != 0) return c;
-  }
   if (a->args.filter_count > 0) {
     c = memcmp(a->args.filters, b->args.filters,
                a->args.filter_count * sizeof(*a->args.filters));
@@ -129,7 +118,6 @@ void grpc_subchannel_key_destroy(grpc_exec_ctx *exec_ctx,
   grpc_connector_unref(exec_ctx, k->connector);
   gpr_free((grpc_channel_args *)k->args.filters);
   grpc_channel_args_destroy(exec_ctx, (grpc_channel_args *)k->args.args);
-  gpr_free(k->args.addr);
   gpr_free(k);
 }
 
diff --git a/src/core/ext/lb_policy/pick_first/pick_first.c b/src/core/ext/lb_policy/pick_first/pick_first.c
index 821becff69..9f2aa461be 100644
--- a/src/core/ext/lb_policy/pick_first/pick_first.c
+++ b/src/core/ext/lb_policy/pick_first/pick_first.c
@@ -36,7 +36,9 @@
 #include <grpc/support/alloc.h>
 
 #include "src/core/ext/client_channel/lb_policy_registry.h"
+#include "src/core/ext/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
+#include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/transport/connectivity_state.h"
 
 typedef struct pending_pick {
@@ -466,11 +468,15 @@ static grpc_lb_policy *create_pick_first(grpc_exec_ctx *exec_ctx,
     }
 
     memset(&sc_args, 0, sizeof(grpc_subchannel_args));
-    sc_args.addr = &addresses->addresses[i].address;
-    sc_args.args = args->args;
-
+    grpc_arg addr_arg =
+        grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
+    grpc_channel_args *new_args =
+        grpc_channel_args_copy_and_add(args->args, &addr_arg, 1);
+    gpr_free(addr_arg.value.string);
+    sc_args.args = new_args;
     grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
         exec_ctx, args->client_channel_factory, &sc_args);
+    grpc_channel_args_destroy(exec_ctx, new_args);
 
     if (subchannel != NULL) {
       p->subchannels[subchannel_idx++] = subchannel;
diff --git a/src/core/ext/lb_policy/round_robin/round_robin.c b/src/core/ext/lb_policy/round_robin/round_robin.c
index cb679489c3..d17d8fa057 100644
--- a/src/core/ext/lb_policy/round_robin/round_robin.c
+++ b/src/core/ext/lb_policy/round_robin/round_robin.c
@@ -64,8 +64,10 @@
 #include <grpc/support/alloc.h>
 
 #include "src/core/ext/client_channel/lb_policy_registry.h"
+#include "src/core/ext/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/debug/trace.h"
+#include "src/core/lib/iomgr/sockaddr_utils.h"
 #include "src/core/lib/transport/connectivity_state.h"
 #include "src/core/lib/transport/static_metadata.h"
 
@@ -729,11 +731,15 @@ static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
     if (addresses->addresses[i].is_balancer) continue;
 
     memset(&sc_args, 0, sizeof(grpc_subchannel_args));
-    sc_args.addr = &addresses->addresses[i].address;
-    sc_args.args = args->args;
-
+    grpc_arg addr_arg =
+        grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
+    grpc_channel_args *new_args =
+        grpc_channel_args_copy_and_add(args->args, &addr_arg, 1);
+    gpr_free(addr_arg.value.string);
+    sc_args.args = new_args;
     grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
         exec_ctx, args->client_channel_factory, &sc_args);
+    grpc_channel_args_destroy(exec_ctx, new_args);
 
     if (subchannel != NULL) {
       subchannel_data *sd = gpr_malloc(sizeof(*sd));
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.c b/src/core/ext/transport/chttp2/client/chttp2_connector.c
index 2c5dfaea60..013c96dc70 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.c
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.c
@@ -43,6 +43,7 @@
 
 #include "src/core/ext/client_channel/connector.h"
 #include "src/core/ext/client_channel/http_connect_handshaker.h"
+#include "src/core/ext/client_channel/subchannel.h"
 #include "src/core/ext/transport/chttp2/transport/chttp2_transport.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/handshaker.h"
@@ -220,6 +221,8 @@ static void chttp2_connector_connect(grpc_exec_ctx *exec_ctx,
                                      grpc_connect_out_args *result,
                                      grpc_closure *notify) {
   chttp2_connector *c = (chttp2_connector *)con;
+  grpc_resolved_address addr;
+  grpc_get_subchannel_address_arg(args->channel_args, &addr);
   gpr_mu_lock(&c->mu);
   GPR_ASSERT(c->notify == NULL);
   c->notify = notify;
@@ -231,8 +234,8 @@ static void chttp2_connector_connect(grpc_exec_ctx *exec_ctx,
   GPR_ASSERT(!c->connecting);
   c->connecting = true;
   grpc_tcp_client_connect(exec_ctx, &c->connected, &c->endpoint,
-                          args->interested_parties, args->channel_args,
-                          args->addr, args->deadline);
+                          args->interested_parties, args->channel_args, &addr,
+                          args->deadline);
   gpr_mu_unlock(&c->mu);
 }
 
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.c b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
index 8fe12a2690..68a6a2155d 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
@@ -62,7 +62,7 @@
 #define DEFAULT_WINDOW 65535
 #define DEFAULT_CONNECTION_WINDOW_TARGET (1024 * 1024)
 #define MAX_WINDOW 0x7fffffffu
-
+#define MAX_WRITE_BUFFER_SIZE (64 * 1024 * 1024)
 #define DEFAULT_MAX_HEADER_LIST_SIZE (16 * 1024)
 
 #define MAX_CLIENT_STREAM_ID 0x7fffffffu
@@ -271,6 +271,7 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
      window -- this should by rights be 0 */
   t->force_send_settings = 1 << GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
   t->sent_local_settings = 0;
+  t->write_buffer_size = DEFAULT_WINDOW;
 
   if (is_client) {
     grpc_slice_buffer_add(&t->outbuf, grpc_slice_from_copied_string(
@@ -321,6 +322,11 @@ static void init_transport(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
           grpc_chttp2_hpack_compressor_set_max_usable_size(&t->hpack_compressor,
                                                            (uint32_t)value);
         }
+      } else if (0 == strcmp(channel_args->args[i].key,
+                             GRPC_ARG_HTTP2_WRITE_BUFFER_SIZE)) {
+        t->write_buffer_size = (uint32_t)grpc_channel_arg_get_integer(
+            &channel_args->args[i],
+            (grpc_integer_options){0, 0, MAX_WRITE_BUFFER_SIZE});
       } else {
         static const struct {
           const char *channel_arg_name;
@@ -899,15 +905,22 @@ static bool contains_non_ok_status(grpc_metadata_batch *batch) {
   return false;
 }
 
+static void maybe_become_writable_due_to_send_msg(grpc_exec_ctx *exec_ctx,
+                                                  grpc_chttp2_transport *t,
+                                                  grpc_chttp2_stream *s) {
+  if (s->id != 0 && (!s->write_buffering ||
+                     s->flow_controlled_buffer.length > t->write_buffer_size)) {
+    grpc_chttp2_become_writable(exec_ctx, t, s, true, "op.send_message");
+  }
+}
+
 static void add_fetched_slice_locked(grpc_exec_ctx *exec_ctx,
                                      grpc_chttp2_transport *t,
                                      grpc_chttp2_stream *s) {
   s->fetched_send_message_length +=
       (uint32_t)GRPC_SLICE_LENGTH(s->fetching_slice);
   grpc_slice_buffer_add(&s->flow_controlled_buffer, s->fetching_slice);
-  if (s->id != 0) {
-    grpc_chttp2_become_writable(exec_ctx, t, s, true, "op.send_message");
-  }
+  maybe_become_writable_due_to_send_msg(exec_ctx, t, s);
 }
 
 static void continue_fetching_send_locked(grpc_exec_ctx *exec_ctx,
@@ -1100,14 +1113,13 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
                                    (int64_t)len;
       s->complete_fetch_covered_by_poller = op->covered_by_poller;
       if (flags & GRPC_WRITE_BUFFER_HINT) {
-        /* allow up to 64kb to be buffered */
-        /* TODO(ctiller): make this configurable */
-        s->next_message_end_offset -= 65536;
+        s->next_message_end_offset -= t->write_buffer_size;
+        s->write_buffering = true;
+      } else {
+        s->write_buffering = false;
       }
       continue_fetching_send_locked(exec_ctx, t, s);
-      if (s->id != 0) {
-        grpc_chttp2_become_writable(exec_ctx, t, s, true, "op.send_message");
-      }
+      maybe_become_writable_due_to_send_msg(exec_ctx, t, s);
     }
   }
 
@@ -1116,6 +1128,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
     on_complete->next_data.scratch |= CLOSURE_BARRIER_MAY_COVER_WRITE;
     s->send_trailing_metadata_finished = add_closure_barrier(on_complete);
     s->send_trailing_metadata = op->send_trailing_metadata;
+    s->write_buffering = false;
     const size_t metadata_size =
         grpc_metadata_batch_size(op->send_trailing_metadata);
     const size_t metadata_peer_limit =
diff --git a/src/core/ext/transport/chttp2/transport/internal.h b/src/core/ext/transport/chttp2/transport/internal.h
index a52acbacdb..ea7beb4c2b 100644
--- a/src/core/ext/transport/chttp2/transport/internal.h
+++ b/src/core/ext/transport/chttp2/transport/internal.h
@@ -249,6 +249,9 @@ struct grpc_chttp2_transport {
   int64_t announce_incoming_window;
   /** how much window would we like to have for incoming_window */
   uint32_t connection_window_target;
+  /** how much data are we willing to buffer when the WRITE_BUFFER_HINT is set?
+   */
+  uint32_t write_buffer_size;
 
   /** have we seen a goaway */
   uint8_t seen_goaway;
@@ -403,6 +406,9 @@ struct grpc_chttp2_stream {
   /** Has this stream seen an error.
       If true, then pending incoming frames can be thrown away. */
   bool seen_error;
+  /** Are we buffering writes on this stream? If yes, we won't become writable
+      until there's enough queued up in the flow_controlled_buffer */
+  bool write_buffering;
 
   /** the error that resulted in this stream being read-closed */
   grpc_error *read_closed_error;
diff --git a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
index df1acddcc0..477cf07f45 100644
--- a/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
+++ b/src/core/ext/transport/cronet/client/secure/cronet_channel_create.c
@@ -60,7 +60,7 @@ GRPCAPI grpc_channel *grpc_cronet_secure_channel_create(
   ct->host = gpr_malloc(strlen(target) + 1);
   strcpy(ct->host, target);
   gpr_log(GPR_DEBUG,
-          "grpc_create_cronet_transport: cronet_engine = %p, target=%s", engine,
+          "grpc_create_cronet_transport: stream_engine = %p, target=%s", engine,
           ct->host);
 
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
diff --git a/src/core/ext/transport/cronet/transport/cronet_api_dummy.c b/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
index 38755604b9..74327a4214 100644
--- a/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
+++ b/src/core/ext/transport/cronet/transport/cronet_api_dummy.c
@@ -38,46 +38,45 @@ library, so we can build it in all environments */
 
 #include <grpc/support/log.h>
 
-#include "third_party/objective_c/Cronet/cronet_c_for_grpc.h"
+#include "third_party/Cronet/bidirectional_stream_c.h"
 
 #ifdef GRPC_COMPILE_WITH_CRONET
 /* link with the real CRONET library in the build system */
 #else
 /* Dummy implementation of cronet API just to test for build-ability */
-cronet_bidirectional_stream* cronet_bidirectional_stream_create(
-    cronet_engine* engine, void* annotation,
-    cronet_bidirectional_stream_callback* callback) {
+bidirectional_stream* bidirectional_stream_create(
+    stream_engine* engine, void* annotation,
+    bidirectional_stream_callback* callback) {
   GPR_ASSERT(0);
   return NULL;
 }
 
-int cronet_bidirectional_stream_destroy(cronet_bidirectional_stream* stream) {
+int bidirectional_stream_destroy(bidirectional_stream* stream) {
   GPR_ASSERT(0);
   return 0;
 }
 
-int cronet_bidirectional_stream_start(
-    cronet_bidirectional_stream* stream, const char* url, int priority,
-    const char* method, const cronet_bidirectional_stream_header_array* headers,
-    bool end_of_stream) {
+int bidirectional_stream_start(bidirectional_stream* stream, const char* url,
+                               int priority, const char* method,
+                               const bidirectional_stream_header_array* headers,
+                               bool end_of_stream) {
   GPR_ASSERT(0);
   return 0;
 }
 
-int cronet_bidirectional_stream_read(cronet_bidirectional_stream* stream,
-                                     char* buffer, int capacity) {
+int bidirectional_stream_read(bidirectional_stream* stream, char* buffer,
+                              int capacity) {
   GPR_ASSERT(0);
   return 0;
 }
 
-int cronet_bidirectional_stream_write(cronet_bidirectional_stream* stream,
-                                      const char* buffer, int count,
-                                      bool end_of_stream) {
+int bidirectional_stream_write(bidirectional_stream* stream, const char* buffer,
+                               int count, bool end_of_stream) {
   GPR_ASSERT(0);
   return 0;
 }
 
-void cronet_bidirectional_stream_cancel(cronet_bidirectional_stream* stream) {
+void bidirectional_stream_cancel(bidirectional_stream* stream) {
   GPR_ASSERT(0);
 }
 
diff --git a/src/core/ext/transport/cronet/transport/cronet_transport.c b/src/core/ext/transport/cronet/transport/cronet_transport.c
index 96ff6ef772..447f3f31ec 100644
--- a/src/core/ext/transport/cronet/transport/cronet_transport.c
+++ b/src/core/ext/transport/cronet/transport/cronet_transport.c
@@ -49,7 +49,7 @@
 #include "src/core/lib/transport/metadata_batch.h"
 #include "src/core/lib/transport/static_metadata.h"
 #include "src/core/lib/transport/transport_impl.h"
-#include "third_party/objective_c/Cronet/cronet_c_for_grpc.h"
+#include "third_party/Cronet/bidirectional_stream_c.h"
 
 #define GRPC_HEADER_SIZE_IN_BYTES 5
 
@@ -86,19 +86,18 @@ enum e_op_id {
 
 /* Cronet callbacks. See cronet_c_for_grpc.h for documentation for each. */
 
-static void on_stream_ready(cronet_bidirectional_stream *);
+static void on_stream_ready(bidirectional_stream *);
 static void on_response_headers_received(
-    cronet_bidirectional_stream *,
-    const cronet_bidirectional_stream_header_array *, const char *);
-static void on_write_completed(cronet_bidirectional_stream *, const char *);
-static void on_read_completed(cronet_bidirectional_stream *, char *, int);
+    bidirectional_stream *, const bidirectional_stream_header_array *,
+    const char *);
+static void on_write_completed(bidirectional_stream *, const char *);
+static void on_read_completed(bidirectional_stream *, char *, int);
 static void on_response_trailers_received(
-    cronet_bidirectional_stream *,
-    const cronet_bidirectional_stream_header_array *);
-static void on_succeeded(cronet_bidirectional_stream *);
-static void on_failed(cronet_bidirectional_stream *, int);
-static void on_canceled(cronet_bidirectional_stream *);
-static cronet_bidirectional_stream_callback cronet_callbacks = {
+    bidirectional_stream *, const bidirectional_stream_header_array *);
+static void on_succeeded(bidirectional_stream *);
+static void on_failed(bidirectional_stream *, int);
+static void on_canceled(bidirectional_stream *);
+static bidirectional_stream_callback cronet_callbacks = {
     on_stream_ready,
     on_response_headers_received,
     on_read_completed,
@@ -111,7 +110,7 @@ static cronet_bidirectional_stream_callback cronet_callbacks = {
 /* Cronet transport object */
 struct grpc_cronet_transport {
   grpc_transport base; /* must be first element in this structure */
-  cronet_engine *engine;
+  stream_engine *engine;
   char *host;
 };
 typedef struct grpc_cronet_transport grpc_cronet_transport;
@@ -181,8 +180,8 @@ struct stream_obj {
   grpc_transport_stream_op *curr_op;
   grpc_cronet_transport curr_ct;
   grpc_stream *curr_gs;
-  cronet_bidirectional_stream *cbs;
-  cronet_bidirectional_stream_header_array header_array;
+  bidirectional_stream *cbs;
+  bidirectional_stream_header_array header_array;
 
   /* Stream level state. Some state will be tracked both at stream and stream_op
    * level */
@@ -352,11 +351,11 @@ static void execute_from_storage(stream_obj *s) {
 /*
   Cronet callback
 */
-static void on_failed(cronet_bidirectional_stream *stream, int net_error) {
+static void on_failed(bidirectional_stream *stream, int net_error) {
   CRONET_LOG(GPR_DEBUG, "on_failed(%p, %d)", stream, net_error);
   stream_obj *s = (stream_obj *)stream->annotation;
   gpr_mu_lock(&s->mu);
-  cronet_bidirectional_stream_destroy(s->cbs);
+  bidirectional_stream_destroy(s->cbs);
   s->state.state_callback_received[OP_FAILED] = true;
   s->cbs = NULL;
   if (s->header_array.headers) {
@@ -375,11 +374,11 @@ static void on_failed(cronet_bidirectional_stream *stream, int net_error) {
 /*
   Cronet callback
 */
-static void on_canceled(cronet_bidirectional_stream *stream) {
+static void on_canceled(bidirectional_stream *stream) {
   CRONET_LOG(GPR_DEBUG, "on_canceled(%p)", stream);
   stream_obj *s = (stream_obj *)stream->annotation;
   gpr_mu_lock(&s->mu);
-  cronet_bidirectional_stream_destroy(s->cbs);
+  bidirectional_stream_destroy(s->cbs);
   s->state.state_callback_received[OP_CANCELED] = true;
   s->cbs = NULL;
   if (s->header_array.headers) {
@@ -398,11 +397,11 @@ static void on_canceled(cronet_bidirectional_stream *stream) {
 /*
   Cronet callback
 */
-static void on_succeeded(cronet_bidirectional_stream *stream) {
+static void on_succeeded(bidirectional_stream *stream) {
   CRONET_LOG(GPR_DEBUG, "on_succeeded(%p)", stream);
   stream_obj *s = (stream_obj *)stream->annotation;
   gpr_mu_lock(&s->mu);
-  cronet_bidirectional_stream_destroy(s->cbs);
+  bidirectional_stream_destroy(s->cbs);
   s->state.state_callback_received[OP_SUCCEEDED] = true;
   s->cbs = NULL;
   free_read_buffer(s);
@@ -413,7 +412,7 @@ static void on_succeeded(cronet_bidirectional_stream *stream) {
 /*
   Cronet callback
 */
-static void on_stream_ready(cronet_bidirectional_stream *stream) {
+static void on_stream_ready(bidirectional_stream *stream) {
   CRONET_LOG(GPR_DEBUG, "W: on_stream_ready(%p)", stream);
   stream_obj *s = (stream_obj *)stream->annotation;
   gpr_mu_lock(&s->mu);
@@ -429,7 +428,7 @@ static void on_stream_ready(cronet_bidirectional_stream *stream) {
 #ifdef GRPC_CRONET_WITH_PACKET_COALESCING
   if (s->state.flush_cronet_when_ready) {
     CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_flush (%p)", s->cbs);
-    cronet_bidirectional_stream_flush(stream);
+    bidirectional_stream_flush(stream);
   }
 #endif
   gpr_mu_unlock(&s->mu);
@@ -440,8 +439,8 @@ static void on_stream_ready(cronet_bidirectional_stream *stream) {
   Cronet callback
 */
 static void on_response_headers_received(
-    cronet_bidirectional_stream *stream,
-    const cronet_bidirectional_stream_header_array *headers,
+    bidirectional_stream *stream,
+    const bidirectional_stream_header_array *headers,
     const char *negotiated_protocol) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   CRONET_LOG(GPR_DEBUG, "R: on_response_headers_received(%p, %p, %s)", stream,
@@ -467,9 +466,9 @@ static void on_response_headers_received(
     s->state.rs.read_buffer = s->state.rs.grpc_header_bytes;
     s->state.rs.received_bytes = 0;
     s->state.rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
-    CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
-    cronet_bidirectional_stream_read(s->cbs, s->state.rs.read_buffer,
-                                     s->state.rs.remaining_bytes);
+    CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
+    bidirectional_stream_read(s->cbs, s->state.rs.read_buffer,
+                              s->state.rs.remaining_bytes);
   }
   gpr_mu_unlock(&s->mu);
   grpc_exec_ctx_finish(&exec_ctx);
@@ -479,8 +478,7 @@ static void on_response_headers_received(
 /*
   Cronet callback
 */
-static void on_write_completed(cronet_bidirectional_stream *stream,
-                               const char *data) {
+static void on_write_completed(bidirectional_stream *stream, const char *data) {
   stream_obj *s = (stream_obj *)stream->annotation;
   CRONET_LOG(GPR_DEBUG, "W: on_write_completed(%p, %s)", stream, data);
   gpr_mu_lock(&s->mu);
@@ -496,7 +494,7 @@ static void on_write_completed(cronet_bidirectional_stream *stream,
 /*
   Cronet callback
 */
-static void on_read_completed(cronet_bidirectional_stream *stream, char *data,
+static void on_read_completed(bidirectional_stream *stream, char *data,
                               int count) {
   stream_obj *s = (stream_obj *)stream->annotation;
   CRONET_LOG(GPR_DEBUG, "R: on_read_completed(%p, %p, %d)", stream, data,
@@ -504,16 +502,16 @@ static void on_read_completed(cronet_bidirectional_stream *stream, char *data,
   gpr_mu_lock(&s->mu);
   s->state.state_callback_received[OP_RECV_MESSAGE] = true;
   if (count > 0 && s->state.flush_read) {
-    CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
-    cronet_bidirectional_stream_read(s->cbs, s->state.rs.read_buffer, 4096);
+    CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
+    bidirectional_stream_read(s->cbs, s->state.rs.read_buffer, 4096);
     gpr_mu_unlock(&s->mu);
   } else if (count > 0) {
     s->state.rs.received_bytes += count;
     s->state.rs.remaining_bytes -= count;
     if (s->state.rs.remaining_bytes > 0) {
-      CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
+      CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
       s->state.state_op_done[OP_READ_REQ_MADE] = true;
-      cronet_bidirectional_stream_read(
+      bidirectional_stream_read(
           s->cbs, s->state.rs.read_buffer + s->state.rs.received_bytes,
           s->state.rs.remaining_bytes);
       gpr_mu_unlock(&s->mu);
@@ -536,8 +534,8 @@ static void on_read_completed(cronet_bidirectional_stream *stream, char *data,
   Cronet callback
 */
 static void on_response_trailers_received(
-    cronet_bidirectional_stream *stream,
-    const cronet_bidirectional_stream_header_array *trailers) {
+    bidirectional_stream *stream,
+    const bidirectional_stream_header_array *trailers) {
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   CRONET_LOG(GPR_DEBUG, "R: on_response_trailers_received(%p,%p)", stream,
              trailers);
@@ -567,12 +565,12 @@ static void on_response_trailers_received(
   if (!s->state.state_op_done[OP_SEND_TRAILING_METADATA] &&
       !(s->state.state_op_done[OP_CANCEL_ERROR] ||
         s->state.state_callback_received[OP_FAILED])) {
-    CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_write (%p, 0)", s->cbs);
+    CRONET_LOG(GPR_DEBUG, "bidirectional_stream_write (%p, 0)", s->cbs);
     s->state.state_callback_received[OP_SEND_MESSAGE] = false;
-    cronet_bidirectional_stream_write(s->cbs, "", 0, true);
+    bidirectional_stream_write(s->cbs, "", 0, true);
 #ifdef GRPC_CRONET_WITH_PACKET_COALESCING
-    CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_flush (%p)", s->cbs);
-    cronet_bidirectional_stream_flush(s->cbs);
+    CRONET_LOG(GPR_DEBUG, "bidirectional_stream_flush (%p)", s->cbs);
+    bidirectional_stream_flush(s->cbs);
 #endif
     s->state.state_op_done[OP_SEND_TRAILING_METADATA] = true;
 
@@ -614,7 +612,7 @@ static void create_grpc_frame(grpc_slice_buffer *write_slice_buffer,
 */
 static void convert_metadata_to_cronet_headers(
     grpc_linked_mdelem *head, const char *host, char **pp_url,
-    cronet_bidirectional_stream_header **pp_headers, size_t *p_num_headers,
+    bidirectional_stream_header **pp_headers, size_t *p_num_headers,
     const char **method) {
   grpc_linked_mdelem *curr = head;
   /* Walk the linked list and get number of header fields */
@@ -625,9 +623,9 @@ static void convert_metadata_to_cronet_headers(
   }
   /* Allocate enough memory. It is freed in the on_stream_ready callback
    */
-  cronet_bidirectional_stream_header *headers =
-      (cronet_bidirectional_stream_header *)gpr_malloc(
-          sizeof(cronet_bidirectional_stream_header) * num_headers_available);
+  bidirectional_stream_header *headers =
+      (bidirectional_stream_header *)gpr_malloc(
+          sizeof(bidirectional_stream_header) * num_headers_available);
   *pp_headers = headers;
 
   /* Walk the linked list again, this time copying the header fields.
@@ -857,12 +855,12 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
      * on_failed */
     GPR_ASSERT(s->cbs == NULL);
     GPR_ASSERT(!stream_state->state_op_done[OP_SEND_INITIAL_METADATA]);
-    s->cbs = cronet_bidirectional_stream_create(s->curr_ct.engine, s->curr_gs,
-                                                &cronet_callbacks);
-    CRONET_LOG(GPR_DEBUG, "%p = cronet_bidirectional_stream_create()", s->cbs);
+    s->cbs = bidirectional_stream_create(s->curr_ct.engine, s->curr_gs,
+                                         &cronet_callbacks);
+    CRONET_LOG(GPR_DEBUG, "%p = bidirectional_stream_create()", s->cbs);
 #ifdef GRPC_CRONET_WITH_PACKET_COALESCING
-    cronet_bidirectional_stream_disable_auto_flush(s->cbs, true);
-    cronet_bidirectional_stream_delay_request_headers_until_flush(s->cbs, true);
+    bidirectional_stream_disable_auto_flush(s->cbs, true);
+    bidirectional_stream_delay_request_headers_until_flush(s->cbs, true);
 #endif
     char *url = NULL;
     const char *method = "POST";
@@ -871,10 +869,8 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
         stream_op->send_initial_metadata->list.head, s->curr_ct.host, &url,
         &s->header_array.headers, &s->header_array.count, &method);
     s->header_array.capacity = s->header_array.count;
-    CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_start(%p, %s)", s->cbs,
-               url);
-    cronet_bidirectional_stream_start(s->cbs, url, 0, method, &s->header_array,
-                                      false);
+    CRONET_LOG(GPR_DEBUG, "bidirectional_stream_start(%p, %s)", s->cbs, url);
+    bidirectional_stream_start(s->cbs, url, 0, method, &s->header_array, false);
     stream_state->state_op_done[OP_SEND_INITIAL_METADATA] = true;
 #ifdef GRPC_CRONET_WITH_PACKET_COALESCING
     if (!stream_op->send_message && !stream_op->send_trailing_metadata) {
@@ -912,16 +908,16 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
         size_t write_buffer_size;
         create_grpc_frame(&write_slice_buffer, &stream_state->ws.write_buffer,
                           &write_buffer_size);
-        CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_write (%p, %p)",
-                   s->cbs, stream_state->ws.write_buffer);
+        CRONET_LOG(GPR_DEBUG, "bidirectional_stream_write (%p, %p)", s->cbs,
+                   stream_state->ws.write_buffer);
         stream_state->state_callback_received[OP_SEND_MESSAGE] = false;
-        cronet_bidirectional_stream_write(s->cbs, stream_state->ws.write_buffer,
-                                          (int)write_buffer_size, false);
+        bidirectional_stream_write(s->cbs, stream_state->ws.write_buffer,
+                                   (int)write_buffer_size, false);
 #ifdef GRPC_CRONET_WITH_PACKET_COALESCING
         if (!stream_op->send_trailing_metadata) {
-          CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_flush (%p)",
+          CRONET_LOG(GPR_DEBUG, "bidirectional_stream_flush (%p)",
                      s->cbs);
-          cronet_bidirectional_stream_flush(s->cbs);
+          bidirectional_stream_flush(s->cbs);
           result = ACTION_TAKEN_WITH_CALLBACK;
         } else {
           stream_state->pending_write_for_trailer = true;
@@ -944,13 +940,13 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       result = NO_ACTION_POSSIBLE;
       CRONET_LOG(GPR_DEBUG, "Stream is either cancelled or failed.");
     } else {
-      CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_write (%p, 0)",
+      CRONET_LOG(GPR_DEBUG, "bidirectional_stream_write (%p, 0)",
                  s->cbs);
       stream_state->state_callback_received[OP_SEND_MESSAGE] = false;
-      cronet_bidirectional_stream_write(s->cbs, "", 0, true);
+      bidirectional_stream_write(s->cbs, "", 0, true);
 #ifdef GRPC_CRONET_WITH_PACKET_COALESCING
-      CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_flush (%p)", s->cbs);
-      cronet_bidirectional_stream_flush(s->cbs);
+      CRONET_LOG(GPR_DEBUG, "bidirectional_stream_flush (%p)", s->cbs);
+      bidirectional_stream_flush(s->cbs);
 #endif
       result = ACTION_TAKEN_WITH_CALLBACK;
     }
@@ -981,14 +977,13 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
     if (stream_state->state_op_done[OP_CANCEL_ERROR]) {
       CRONET_LOG(GPR_DEBUG, "Stream is cancelled.");
       grpc_closure_sched(exec_ctx, stream_op->recv_message_ready,
-                         GRPC_ERROR_CANCELLED);
+                         GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
       result = ACTION_TAKEN_NO_CALLBACK;
     } else if (stream_state->state_callback_received[OP_FAILED]) {
       CRONET_LOG(GPR_DEBUG, "Stream failed.");
-      grpc_closure_sched(
-          exec_ctx, stream_op->recv_message_ready,
-          make_error_with_desc(GRPC_STATUS_UNAVAILABLE, "Unavailable."));
+      grpc_closure_sched(exec_ctx, stream_op->recv_message_ready,
+                         GRPC_ERROR_NONE);
       stream_state->state_op_done[OP_RECV_MESSAGE] = true;
       result = ACTION_TAKEN_NO_CALLBACK;
     } else if (stream_state->rs.read_stream_closed == true) {
@@ -1014,11 +1009,11 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
           GPR_ASSERT(stream_state->rs.read_buffer);
           stream_state->rs.remaining_bytes = stream_state->rs.length_field;
           stream_state->rs.received_bytes = 0;
-          CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
+          CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
           stream_state->state_op_done[OP_READ_REQ_MADE] =
               true; /* Indicates that at least one read request has been made */
-          cronet_bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
-                                           stream_state->rs.remaining_bytes);
+          bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
+                                    stream_state->rs.remaining_bytes);
           result = ACTION_TAKEN_WITH_CALLBACK;
         } else {
           stream_state->rs.remaining_bytes = 0;
@@ -1037,10 +1032,10 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
           stream_state->rs.read_buffer = stream_state->rs.grpc_header_bytes;
           stream_state->rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
           stream_state->rs.received_bytes = 0;
-          CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
+          CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
           stream_state->state_op_done[OP_READ_REQ_MADE] =
               true; /* Indicates that at least one read request has been made */
-          cronet_bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
+          bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
                                            stream_state->rs.remaining_bytes);
           result = ACTION_TAKEN_NO_CALLBACK;
         }
@@ -1049,11 +1044,11 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
         stream_state->rs.read_buffer = stream_state->rs.grpc_header_bytes;
         stream_state->rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
         stream_state->rs.received_bytes = 0;
-        CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
+        CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
         stream_state->state_op_done[OP_READ_REQ_MADE] =
             true; /* Indicates that at least one read request has been made */
-        cronet_bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
-                                         stream_state->rs.remaining_bytes);
+        bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
+                                  stream_state->rs.remaining_bytes);
         result = ACTION_TAKEN_WITH_CALLBACK;
       } else {
         result = NO_ACTION_POSSIBLE;
@@ -1083,9 +1078,9 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       stream_state->rs.received_bytes = 0;
       stream_state->rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
       stream_state->rs.length_field_received = false;
-      CRONET_LOG(GPR_DEBUG, "cronet_bidirectional_stream_read(%p)", s->cbs);
-      cronet_bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
-                                       stream_state->rs.remaining_bytes);
+      CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
+      bidirectional_stream_read(s->cbs, stream_state->rs.read_buffer,
+                                stream_state->rs.remaining_bytes);
       result = ACTION_TAKEN_NO_CALLBACK;
     }
   } else if (stream_op->recv_trailing_metadata &&
@@ -1104,9 +1099,9 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
              op_can_be_run(stream_op, stream_state, &oas->state,
                            OP_CANCEL_ERROR)) {
     CRONET_LOG(GPR_DEBUG, "running: %p  OP_CANCEL_ERROR", oas);
-    CRONET_LOG(GPR_DEBUG, "W: cronet_bidirectional_stream_cancel(%p)", s->cbs);
+    CRONET_LOG(GPR_DEBUG, "W: bidirectional_stream_cancel(%p)", s->cbs);
     if (s->cbs) {
-      cronet_bidirectional_stream_cancel(s->cbs);
+      bidirectional_stream_cancel(s->cbs);
       result = ACTION_TAKEN_WITH_CALLBACK;
     } else {
       result = ACTION_TAKEN_NO_CALLBACK;
@@ -1207,18 +1202,17 @@ static void perform_stream_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
       header_has_authority(op->send_initial_metadata->list.head)) {
     /* Cronet does not support :authority header field. We cancel the call when
        this field is present in metadata */
-    cronet_bidirectional_stream_header_array header_array;
-    cronet_bidirectional_stream_header *header;
-    cronet_bidirectional_stream cbs;
+    bidirectional_stream_header_array header_array;
+    bidirectional_stream_header *header;
+    bidirectional_stream cbs;
     CRONET_LOG(GPR_DEBUG,
                ":authority header is provided but not supported;"
                " cancel operations");
     /* Notify application that operation is cancelled by forging trailers */
     header_array.count = 1;
     header_array.capacity = 1;
-    header_array.headers =
-        gpr_malloc(sizeof(cronet_bidirectional_stream_header));
-    header = (cronet_bidirectional_stream_header *)header_array.headers;
+    header_array.headers = gpr_malloc(sizeof(bidirectional_stream_header));
+    header = (bidirectional_stream_header *)header_array.headers;
     header->key = "grpc-status";
     header->value = "1"; /* Return status GRPC_STATUS_CANCELLED */
     cbs.annotation = (void *)s;
diff --git a/src/core/lib/iomgr/ev_epoll_linux.c b/src/core/lib/iomgr/ev_epoll_linux.c
index d6664aead2..715d057c51 100644
--- a/src/core/lib/iomgr/ev_epoll_linux.c
+++ b/src/core/lib/iomgr/ev_epoll_linux.c
@@ -796,7 +796,7 @@ static polling_island *polling_island_merge(polling_island *p,
     gpr_atm_rel_store(&p->merged_to, (gpr_atm)q);
     PI_ADD_REF(q, "pi_merge"); /* To account for the new incoming ref from p */
 
-    workqueue_move_items_to_parent(q);
+    workqueue_move_items_to_parent(p);
   }
   /* else if p == q, nothing needs to be done */
 
diff --git a/src/core/lib/iomgr/ev_poll_posix.c b/src/core/lib/iomgr/ev_poll_posix.c
index 5bc5621443..9477ac3688 100644
--- a/src/core/lib/iomgr/ev_poll_posix.c
+++ b/src/core/lib/iomgr/ev_poll_posix.c
@@ -413,9 +413,7 @@ static void fd_orphan(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
                       const char *reason) {
   fd->on_done_closure = on_done;
   fd->released = release_fd != NULL;
-  if (!fd->released) {
-    shutdown(fd->fd, SHUT_RDWR);
-  } else {
+  if (fd->released) {
     *release_fd = fd->fd;
   }
   gpr_mu_lock(&fd->mu);
diff --git a/src/core/lib/iomgr/resource_quota.c b/src/core/lib/iomgr/resource_quota.c
index 42a044df77..31590cd53b 100644
--- a/src/core/lib/iomgr/resource_quota.c
+++ b/src/core/lib/iomgr/resource_quota.c
@@ -691,6 +691,11 @@ grpc_resource_user *grpc_resource_user_create(
   return resource_user;
 }
 
+grpc_resource_quota *grpc_resource_user_quota(
+    grpc_resource_user *resource_user) {
+  return resource_user->resource_quota;
+}
+
 static void ru_ref_by(grpc_resource_user *resource_user, gpr_atm amount) {
   GPR_ASSERT(amount > 0);
   GPR_ASSERT(gpr_atm_no_barrier_fetch_add(&resource_user->refs, amount) != 0);
diff --git a/src/core/lib/iomgr/resource_quota.h b/src/core/lib/iomgr/resource_quota.h
index ef286c2fce..d1127ce9ea 100644
--- a/src/core/lib/iomgr/resource_quota.h
+++ b/src/core/lib/iomgr/resource_quota.h
@@ -88,6 +88,12 @@ typedef struct grpc_resource_user grpc_resource_user;
 
 grpc_resource_user *grpc_resource_user_create(
     grpc_resource_quota *resource_quota, const char *name);
+
+/* Returns a borrowed reference to the underlying resource quota for this
+   resource user. */
+grpc_resource_quota *grpc_resource_user_quota(
+    grpc_resource_user *resource_user);
+
 void grpc_resource_user_ref(grpc_resource_user *resource_user);
 void grpc_resource_user_unref(grpc_exec_ctx *exec_ctx,
                               grpc_resource_user *resource_user);