Merge branch 'master' of github.com:grpc/grpc into grpclb_api

26 files changed, 381 insertions, 356 deletions

diff --git a/src/core/transport/chttp2/frame_data.c b/src/core/transport/chttp2/frame_data.c
index e07fbb2cc7..60a3ce23d5 100644
--- a/src/core/transport/chttp2/frame_data.c
+++ b/src/core/transport/chttp2/frame_data.c
@@ -53,7 +53,8 @@ void grpc_chttp2_data_parser_destroy(grpc_exec_ctx *exec_ctx,
                                      grpc_chttp2_data_parser *parser) {
   grpc_byte_stream *bs;
   if (parser->parsing_frame) {
-    grpc_chttp2_incoming_byte_stream_finished(exec_ctx, parser->parsing_frame);
+    grpc_chttp2_incoming_byte_stream_finished(exec_ctx, parser->parsing_frame,
+                                              0, 1);
   }
   while (
       (bs = grpc_chttp2_incoming_frame_queue_pop(&parser->incoming_frames))) {
@@ -118,7 +119,7 @@ void grpc_chttp2_encode_data(gpr_uint32 id, gpr_slice_buffer *inbuf,
 
   hdr = gpr_slice_malloc(9);
   p = GPR_SLICE_START_PTR(hdr);
-  GPR_ASSERT(write_bytes < 16777316);
+  GPR_ASSERT(write_bytes < (1 << 24));
   *p++ = (gpr_uint8)(write_bytes >> 16);
   *p++ = (gpr_uint8)(write_bytes >> 8);
   *p++ = (gpr_uint8)(write_bytes);
@@ -218,7 +219,8 @@ grpc_chttp2_parse_error grpc_chttp2_data_parser_parse(
         grpc_chttp2_incoming_byte_stream_push(
             exec_ctx, p->parsing_frame,
             gpr_slice_sub(slice, (size_t)(cur - beg), (size_t)(end - beg)));
-        grpc_chttp2_incoming_byte_stream_finished(exec_ctx, p->parsing_frame);
+        grpc_chttp2_incoming_byte_stream_finished(exec_ctx, p->parsing_frame, 1,
+                                                  1);
         p->parsing_frame = NULL;
         p->state = GRPC_CHTTP2_DATA_FH_0;
         return GRPC_CHTTP2_PARSE_OK;
@@ -227,7 +229,8 @@ grpc_chttp2_parse_error grpc_chttp2_data_parser_parse(
             exec_ctx, p->parsing_frame,
             gpr_slice_sub(slice, (size_t)(cur - beg),
                           (size_t)(cur + p->frame_size - beg)));
-        grpc_chttp2_incoming_byte_stream_finished(exec_ctx, p->parsing_frame);
+        grpc_chttp2_incoming_byte_stream_finished(exec_ctx, p->parsing_frame, 1,
+                                                  1);
         p->parsing_frame = NULL;
         cur += p->frame_size;
         goto fh_0; /* loop */
diff --git a/src/core/transport/chttp2/frame_data.h b/src/core/transport/chttp2/frame_data.h
index 472f9cebdb..27d4d0043b 100644
--- a/src/core/transport/chttp2/frame_data.h
+++ b/src/core/transport/chttp2/frame_data.h
@@ -94,9 +94,6 @@ grpc_chttp2_parse_error grpc_chttp2_data_parser_parse(
     grpc_chttp2_transport_parsing *transport_parsing,
     grpc_chttp2_stream_parsing *stream_parsing, gpr_slice slice, int is_last);
 
-/* create a slice with an empty data frame and is_last set */
-gpr_slice grpc_chttp2_data_frame_create_empty_close(gpr_uint32 id);
-
 void grpc_chttp2_encode_data(gpr_uint32 id, gpr_slice_buffer *inbuf,
                              gpr_uint32 write_bytes, int is_eof,
                              gpr_slice_buffer *outbuf);
diff --git a/src/core/transport/chttp2/frame_ping.c b/src/core/transport/chttp2/frame_ping.c
index 4d2c54269d..8e763278ff 100644
--- a/src/core/transport/chttp2/frame_ping.c
+++ b/src/core/transport/chttp2/frame_ping.c
@@ -76,7 +76,6 @@ grpc_chttp2_parse_error grpc_chttp2_ping_parser_parse(
   gpr_uint8 *const end = GPR_SLICE_END_PTR(slice);
   gpr_uint8 *cur = beg;
   grpc_chttp2_ping_parser *p = parser;
-  grpc_chttp2_outstanding_ping *ping;
 
   while (p->byte != 8 && cur != end) {
     p->opaque_8bytes[p->byte] = *cur;
@@ -87,15 +86,7 @@ grpc_chttp2_parse_error grpc_chttp2_ping_parser_parse(
   if (p->byte == 8) {
     GPR_ASSERT(is_last);
     if (p->is_ack) {
-      for (ping = transport_parsing->pings.next;
-           ping != &transport_parsing->pings; ping = ping->next) {
-        if (0 == memcmp(p->opaque_8bytes, ping->id, 8)) {
-          grpc_exec_ctx_enqueue(exec_ctx, ping->on_recv, 1);
-        }
-        ping->next->prev = ping->prev;
-        ping->prev->next = ping->next;
-        gpr_free(ping);
-      }
+      grpc_chttp2_ack_ping(exec_ctx, transport_parsing, p->opaque_8bytes);
     } else {
       gpr_slice_buffer_add(&transport_parsing->qbuf,
                            grpc_chttp2_ping_create(1, p->opaque_8bytes));
diff --git a/src/core/transport/chttp2/frame_settings.c b/src/core/transport/chttp2/frame_settings.c
index d7c9f7ed69..383b6e7f93 100644
--- a/src/core/transport/chttp2/frame_settings.c
+++ b/src/core/transport/chttp2/frame_settings.c
@@ -44,6 +44,8 @@
 #include "src/core/transport/chttp2/http2_errors.h"
 #include "src/core/transport/chttp2_transport.h"
 
+#define MAX_MAX_HEADER_LIST_SIZE (1024 * 1024 * 1024)
+
 /* HTTP/2 mandated initial connection settings */
 const grpc_chttp2_setting_parameters
     grpc_chttp2_settings_parameters[GRPC_CHTTP2_NUM_SETTINGS] = {
@@ -60,8 +62,9 @@ const grpc_chttp2_setting_parameters
          GRPC_CHTTP2_FLOW_CONTROL_ERROR},
         {"MAX_FRAME_SIZE", 16384, 16384, 16777215,
          GRPC_CHTTP2_DISCONNECT_ON_INVALID_VALUE, GRPC_CHTTP2_PROTOCOL_ERROR},
-        {"MAX_HEADER_LIST_SIZE", 0xffffffffu, 0, 0xffffffffu,
-         GRPC_CHTTP2_CLAMP_INVALID_VALUE, GRPC_CHTTP2_PROTOCOL_ERROR},
+        {"MAX_HEADER_LIST_SIZE", MAX_MAX_HEADER_LIST_SIZE, 0,
+         MAX_MAX_HEADER_LIST_SIZE, GRPC_CHTTP2_CLAMP_INVALID_VALUE,
+         GRPC_CHTTP2_PROTOCOL_ERROR},
 };
 
 static gpr_uint8 *fill_header(gpr_uint8 *out, gpr_uint32 length,
diff --git a/src/core/transport/chttp2/hpack_encoder.c b/src/core/transport/chttp2/hpack_encoder.c
index 28d5433d15..6c558bc1cb 100644
--- a/src/core/transport/chttp2/hpack_encoder.c
+++ b/src/core/transport/chttp2/hpack_encoder.c
@@ -365,10 +365,10 @@ static void hpack_enc(grpc_chttp2_hpack_compressor *c, grpc_mdelem *elem,
   GPR_ASSERT(GPR_SLICE_LENGTH(elem->key->slice) > 0);
   if (GPR_SLICE_START_PTR(elem->key->slice)[0] != ':') { /* regular header */
     st->seen_regular_header = 1;
-  } else if (st->seen_regular_header != 0) { /* reserved header */
-    gpr_log(GPR_ERROR,
-            "Reserved header (colon-prefixed) happening after regular ones.");
-    abort();
+  } else {
+    GPR_ASSERT(
+        st->seen_regular_header == 0 &&
+        "Reserved header (colon-prefixed) happening after regular ones.");
   }
 
   inc_filter(HASH_FRAGMENT_1(elem_hash), &c->filter_elems_sum, c->filter_elems);
@@ -458,12 +458,6 @@ static void deadline_enc(grpc_chttp2_hpack_compressor *c, gpr_timespec deadline,
   GRPC_MDELEM_UNREF(mdelem);
 }
 
-gpr_slice grpc_chttp2_data_frame_create_empty_close(gpr_uint32 id) {
-  gpr_slice slice = gpr_slice_malloc(9);
-  fill_header(GPR_SLICE_START_PTR(slice), GRPC_CHTTP2_FRAME_DATA, id, 0, 1);
-  return slice;
-}
-
 static gpr_uint32 elems_for_bytes(gpr_uint32 bytes) {
   return (bytes + 31) / 32;
 }
diff --git a/src/core/transport/chttp2/hpack_parser.c b/src/core/transport/chttp2/hpack_parser.c
index d38ff68754..fea0000896 100644
--- a/src/core/transport/chttp2/hpack_parser.c
+++ b/src/core/transport/chttp2/hpack_parser.c
@@ -728,6 +728,7 @@ static int finish_indexed_field(grpc_chttp2_hpack_parser *p,
 /* parse an indexed field with index < 127 */
 static int parse_indexed_field(grpc_chttp2_hpack_parser *p,
                                const gpr_uint8 *cur, const gpr_uint8 *end) {
+  p->dynamic_table_update_allowed = 0;
   p->index = (*cur) & 0x7f;
   return finish_indexed_field(p, cur + 1, end);
 }
@@ -737,6 +738,7 @@ static int parse_indexed_field_x(grpc_chttp2_hpack_parser *p,
                                  const gpr_uint8 *cur, const gpr_uint8 *end) {
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       finish_indexed_field};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = 0x7f;
   p->parsing.value = &p->index;
@@ -748,6 +750,7 @@ static int parse_indexed_field_x(grpc_chttp2_hpack_parser *p,
 static int finish_lithdr_incidx(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
+  GPR_ASSERT(md != NULL); /* handled in string parsing */
   return on_hdr(p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
                                                      take_string(p, &p->value)),
                 1) &&
@@ -768,6 +771,7 @@ static int parse_lithdr_incidx(grpc_chttp2_hpack_parser *p,
                                const gpr_uint8 *cur, const gpr_uint8 *end) {
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_value_string_with_indexed_key, finish_lithdr_incidx};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = (*cur) & 0x3f;
   return parse_string_prefix(p, cur + 1, end);
@@ -779,6 +783,7 @@ static int parse_lithdr_incidx_x(grpc_chttp2_hpack_parser *p,
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_string_prefix, parse_value_string_with_indexed_key,
       finish_lithdr_incidx};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = 0x3f;
   p->parsing.value = &p->index;
@@ -791,6 +796,7 @@ static int parse_lithdr_incidx_v(grpc_chttp2_hpack_parser *p,
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_key_string, parse_string_prefix,
       parse_value_string_with_literal_key, finish_lithdr_incidx_v};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   return parse_string_prefix(p, cur + 1, end);
 }
@@ -799,6 +805,7 @@ static int parse_lithdr_incidx_v(grpc_chttp2_hpack_parser *p,
 static int finish_lithdr_notidx(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
+  GPR_ASSERT(md != NULL); /* handled in string parsing */
   return on_hdr(p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
                                                      take_string(p, &p->value)),
                 0) &&
@@ -819,6 +826,7 @@ static int parse_lithdr_notidx(grpc_chttp2_hpack_parser *p,
                                const gpr_uint8 *cur, const gpr_uint8 *end) {
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_value_string_with_indexed_key, finish_lithdr_notidx};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = (*cur) & 0xf;
   return parse_string_prefix(p, cur + 1, end);
@@ -830,6 +838,7 @@ static int parse_lithdr_notidx_x(grpc_chttp2_hpack_parser *p,
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_string_prefix, parse_value_string_with_indexed_key,
       finish_lithdr_notidx};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = 0xf;
   p->parsing.value = &p->index;
@@ -842,6 +851,7 @@ static int parse_lithdr_notidx_v(grpc_chttp2_hpack_parser *p,
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_key_string, parse_string_prefix,
       parse_value_string_with_literal_key, finish_lithdr_notidx_v};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   return parse_string_prefix(p, cur + 1, end);
 }
@@ -850,6 +860,7 @@ static int parse_lithdr_notidx_v(grpc_chttp2_hpack_parser *p,
 static int finish_lithdr_nvridx(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   grpc_mdelem *md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
+  GPR_ASSERT(md != NULL); /* handled in string parsing */
   return on_hdr(p, grpc_mdelem_from_metadata_strings(GRPC_MDSTR_REF(md->key),
                                                      take_string(p, &p->value)),
                 0) &&
@@ -870,6 +881,7 @@ static int parse_lithdr_nvridx(grpc_chttp2_hpack_parser *p,
                                const gpr_uint8 *cur, const gpr_uint8 *end) {
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_value_string_with_indexed_key, finish_lithdr_nvridx};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = (*cur) & 0xf;
   return parse_string_prefix(p, cur + 1, end);
@@ -881,6 +893,7 @@ static int parse_lithdr_nvridx_x(grpc_chttp2_hpack_parser *p,
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_string_prefix, parse_value_string_with_indexed_key,
       finish_lithdr_nvridx};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   p->index = 0xf;
   p->parsing.value = &p->index;
@@ -893,6 +906,7 @@ static int parse_lithdr_nvridx_v(grpc_chttp2_hpack_parser *p,
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       parse_key_string, parse_string_prefix,
       parse_value_string_with_literal_key, finish_lithdr_nvridx_v};
+  p->dynamic_table_update_allowed = 0;
   p->next_state = and_then;
   return parse_string_prefix(p, cur + 1, end);
 }
@@ -908,6 +922,10 @@ static int finish_max_tbl_size(grpc_chttp2_hpack_parser *p,
 /* parse a max table size change, max size < 15 */
 static int parse_max_tbl_size(grpc_chttp2_hpack_parser *p, const gpr_uint8 *cur,
                               const gpr_uint8 *end) {
+  if (p->dynamic_table_update_allowed == 0) {
+    return 0;
+  }
+  p->dynamic_table_update_allowed--;
   p->index = (*cur) & 0x1f;
   return finish_max_tbl_size(p, cur + 1, end);
 }
@@ -917,6 +935,10 @@ static int parse_max_tbl_size_x(grpc_chttp2_hpack_parser *p,
                                 const gpr_uint8 *cur, const gpr_uint8 *end) {
   static const grpc_chttp2_hpack_parser_state and_then[] = {
       finish_max_tbl_size};
+  if (p->dynamic_table_update_allowed == 0) {
+    return 0;
+  }
+  p->dynamic_table_update_allowed--;
   p->next_state = and_then;
   p->index = 0x1f;
   p->parsing.value = &p->index;
@@ -1044,7 +1066,7 @@ static int parse_value4(grpc_chttp2_hpack_parser *p, const gpr_uint8 *cur,
 error:
   gpr_log(GPR_ERROR,
           "integer overflow in hpack integer decoding: have 0x%08x, "
-          "got byte 0x%02x",
+          "got byte 0x%02x on byte 5",
           *p->parsing.value, *cur);
   return parse_error(p, cur, end);
 }
@@ -1069,7 +1091,8 @@ static int parse_value5up(grpc_chttp2_hpack_parser *p, const gpr_uint8 *cur,
 
   gpr_log(GPR_ERROR,
           "integer overflow in hpack integer decoding: have 0x%08x, "
-          "got byte 0x%02x sometime after byte 4");
+          "got byte 0x%02x sometime after byte 5",
+          *p->parsing.value, *cur);
   return parse_error(p, cur, end);
 }
 
@@ -1300,7 +1323,10 @@ static is_binary_header is_binary_literal_header(grpc_chttp2_hpack_parser *p) {
 
 static is_binary_header is_binary_indexed_header(grpc_chttp2_hpack_parser *p) {
   grpc_mdelem *elem = grpc_chttp2_hptbl_lookup(&p->table, p->index);
-  if (!elem) return ERROR_HEADER;
+  if (!elem) {
+    gpr_log(GPR_ERROR, "Invalid HPACK index received: %d", p->index);
+    return ERROR_HEADER;
+  }
   return grpc_is_binary_header(
              (const char *)GPR_SLICE_START_PTR(elem->key->slice),
              GPR_SLICE_LENGTH(elem->key->slice))
@@ -1338,15 +1364,7 @@ static int parse_value_string_with_literal_key(grpc_chttp2_hpack_parser *p,
 /* PUBLIC INTERFACE */
 
 static void on_header_not_set(void *user_data, grpc_mdelem *md) {
-  char *keyhex = gpr_dump_slice(md->key->slice, GPR_DUMP_HEX | GPR_DUMP_ASCII);
-  char *valuehex =
-      gpr_dump_slice(md->value->slice, GPR_DUMP_HEX | GPR_DUMP_ASCII);
-  gpr_log(GPR_ERROR, "on_header callback not set; key=%s value=%s", keyhex,
-          valuehex);
-  gpr_free(keyhex);
-  gpr_free(valuehex);
-  GRPC_MDELEM_UNREF(md);
-  abort();
+  GPR_UNREACHABLE_CODE(return );
 }
 
 void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p) {
@@ -1359,6 +1377,7 @@ void grpc_chttp2_hpack_parser_init(grpc_chttp2_hpack_parser *p) {
   p->value.str = NULL;
   p->value.capacity = 0;
   p->value.length = 0;
+  p->dynamic_table_update_allowed = 2;
   grpc_chttp2_hptbl_init(&p->table);
 }
 
@@ -1400,20 +1419,25 @@ grpc_chttp2_parse_error grpc_chttp2_header_parser_parse(
       GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
       return GRPC_CHTTP2_CONNECTION_ERROR;
     }
-    if (parser->is_boundary) {
-      stream_parsing
-          ->got_metadata_on_parse[stream_parsing->header_frames_received] = 1;
-      stream_parsing->header_frames_received++;
-      grpc_chttp2_list_add_parsing_seen_stream(transport_parsing,
-                                               stream_parsing);
-    }
-    if (parser->is_eof) {
-      stream_parsing->received_close = 1;
+    /* need to check for null stream: this can occur if we receive an invalid
+       stream id on a header */
+    if (stream_parsing != NULL) {
+      if (parser->is_boundary) {
+        stream_parsing
+            ->got_metadata_on_parse[stream_parsing->header_frames_received] = 1;
+        stream_parsing->header_frames_received++;
+        grpc_chttp2_list_add_parsing_seen_stream(transport_parsing,
+                                                 stream_parsing);
+      }
+      if (parser->is_eof) {
+        stream_parsing->received_close = 1;
+      }
     }
     parser->on_header = on_header_not_set;
     parser->on_header_user_data = NULL;
     parser->is_boundary = 0xde;
     parser->is_eof = 0xde;
+    parser->dynamic_table_update_allowed = 2;
   }
   GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
   return GRPC_CHTTP2_PARSE_OK;
diff --git a/src/core/transport/chttp2/hpack_parser.h b/src/core/transport/chttp2/hpack_parser.h
index fb894b5735..bd36357124 100644
--- a/src/core/transport/chttp2/hpack_parser.h
+++ b/src/core/transport/chttp2/hpack_parser.h
@@ -85,6 +85,8 @@ struct grpc_chttp2_hpack_parser {
   gpr_uint8 binary;
   /* is the current string huffman encoded? */
   gpr_uint8 huff;
+  /* is a dynamic table update allowed? */
+  gpr_uint8 dynamic_table_update_allowed;
   /* set by higher layers, used by grpc_chttp2_header_parser_parse to signal
      it should append a metadata boundary at the end of frame */
   gpr_uint8 is_boundary;
diff --git a/src/core/transport/chttp2/incoming_metadata.c b/src/core/transport/chttp2/incoming_metadata.c
index 956afc8e9d..315bc2faa1 100644
--- a/src/core/transport/chttp2/incoming_metadata.c
+++ b/src/core/transport/chttp2/incoming_metadata.c
@@ -56,16 +56,6 @@ void grpc_chttp2_incoming_metadata_buffer_destroy(
   gpr_free(buffer->elems);
 }
 
-void grpc_chttp2_incoming_metadata_buffer_reset(
-    grpc_chttp2_incoming_metadata_buffer *buffer) {
-  size_t i;
-  GPR_ASSERT(!buffer->published);
-  for (i = 0; i < buffer->count; i++) {
-    GRPC_MDELEM_UNREF(buffer->elems[i].md);
-  }
-  buffer->count = 0;
-}
-
 void grpc_chttp2_incoming_metadata_buffer_add(
     grpc_chttp2_incoming_metadata_buffer *buffer, grpc_mdelem *elem) {
   GPR_ASSERT(!buffer->published);
@@ -83,14 +73,6 @@ void grpc_chttp2_incoming_metadata_buffer_set_deadline(
   buffer->deadline = deadline;
 }
 
-void grpc_chttp2_incoming_metadata_buffer_swap(
-    grpc_chttp2_incoming_metadata_buffer *a,
-    grpc_chttp2_incoming_metadata_buffer *b) {
-  GPR_ASSERT(!a->published);
-  GPR_ASSERT(!b->published);
-  GPR_SWAP(grpc_chttp2_incoming_metadata_buffer, *a, *b);
-}
-
 void grpc_chttp2_incoming_metadata_buffer_publish(
     grpc_chttp2_incoming_metadata_buffer *buffer, grpc_metadata_batch *batch) {
   GPR_ASSERT(!buffer->published);
diff --git a/src/core/transport/chttp2/incoming_metadata.h b/src/core/transport/chttp2/incoming_metadata.h
index 0e1dabe825..ea74cfc64b 100644
--- a/src/core/transport/chttp2/incoming_metadata.h
+++ b/src/core/transport/chttp2/incoming_metadata.h
@@ -49,8 +49,6 @@ void grpc_chttp2_incoming_metadata_buffer_init(
     grpc_chttp2_incoming_metadata_buffer *buffer);
 void grpc_chttp2_incoming_metadata_buffer_destroy(
     grpc_chttp2_incoming_metadata_buffer *buffer);
-void grpc_chttp2_incoming_metadata_buffer_reset(
-    grpc_chttp2_incoming_metadata_buffer *buffer);
 void grpc_chttp2_incoming_metadata_buffer_publish(
     grpc_chttp2_incoming_metadata_buffer *buffer, grpc_metadata_batch *batch);
 
diff --git a/src/core/transport/chttp2/internal.h b/src/core/transport/chttp2/internal.h
index 3952f8a0e8..4ad900378b 100644
--- a/src/core/transport/chttp2/internal.h
+++ b/src/core/transport/chttp2/internal.h
@@ -65,6 +65,7 @@ typedef enum {
   GRPC_CHTTP2_LIST_WRITTEN,
   GRPC_CHTTP2_LIST_PARSING_SEEN,
   GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_PARSING,
+  GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_WRITING,
   GRPC_CHTTP2_LIST_STALLED_BY_TRANSPORT,
   /** streams that are waiting to start because there are too many concurrent
       streams on the connection */
@@ -151,6 +152,7 @@ struct grpc_chttp2_incoming_byte_stream {
   grpc_byte_stream base;
   gpr_refcount refs;
   struct grpc_chttp2_incoming_byte_stream *next_message;
+  int failed;
 
   grpc_chttp2_transport *transport;
   grpc_chttp2_stream *stream;
@@ -283,9 +285,6 @@ struct grpc_chttp2_transport_parsing {
   gpr_slice goaway_text;
 
   gpr_int64 outgoing_window;
-
-  /** pings awaiting responses */
-  grpc_chttp2_outstanding_ping pings;
 };
 
 struct grpc_chttp2_transport {
@@ -394,8 +393,6 @@ typedef struct {
   gpr_uint8 write_closed;
   /** is this stream reading half-closed (boolean) */
   gpr_uint8 read_closed;
-  /** is this stream finished closing (and reportably closed) */
-  gpr_uint8 finished_close;
   /** is this stream in the stream map? (boolean) */
   gpr_uint8 in_stream_map;
   /** has this stream seen an error? if 1, then pending incoming frames
@@ -512,9 +509,6 @@ void grpc_chttp2_publish_reads(grpc_exec_ctx *exec_ctx,
 void grpc_chttp2_list_add_writable_stream(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global);
-void grpc_chttp2_list_add_first_writable_stream(
-    grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global *stream_global);
 int grpc_chttp2_list_pop_writable_stream(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_transport_writing *transport_writing,
@@ -592,6 +586,13 @@ int grpc_chttp2_list_pop_closed_waiting_for_parsing(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global **stream_global);
 
+void grpc_chttp2_list_add_closed_waiting_for_writing(
+    grpc_chttp2_transport_global *transport_global,
+    grpc_chttp2_stream_global *stream_global);
+int grpc_chttp2_list_pop_closed_waiting_for_writing(
+    grpc_chttp2_transport_global *transport_global,
+    grpc_chttp2_stream_global **stream_global);
+
 grpc_chttp2_stream_parsing *grpc_chttp2_parsing_lookup_stream(
     grpc_chttp2_transport_parsing *transport_parsing, gpr_uint32 id);
 grpc_chttp2_stream_parsing *grpc_chttp2_parsing_accept_stream(
@@ -748,6 +749,11 @@ void grpc_chttp2_incoming_byte_stream_push(grpc_exec_ctx *exec_ctx,
                                            grpc_chttp2_incoming_byte_stream *bs,
                                            gpr_slice slice);
 void grpc_chttp2_incoming_byte_stream_finished(
-    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs);
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs, int success,
+    int from_parsing_thread);
+
+void grpc_chttp2_ack_ping(grpc_exec_ctx *exec_ctx,
+                          grpc_chttp2_transport_parsing *parsing,
+                          const gpr_uint8 *opaque_8bytes);
 
 #endif
diff --git a/src/core/transport/chttp2/parsing.c b/src/core/transport/chttp2/parsing.c
index eb2cb6b4c2..7604e7b681 100644
--- a/src/core/transport/chttp2/parsing.c
+++ b/src/core/transport/chttp2/parsing.c
@@ -604,7 +604,7 @@ static void on_initial_header(void *tp, grpc_mdelem *md) {
                                       cached_timeout)) {
         gpr_log(GPR_ERROR, "Ignoring bad timeout value '%s'",
                 grpc_mdstr_as_c_string(md->value));
-        *cached_timeout = gpr_inf_future(GPR_CLOCK_REALTIME);
+        *cached_timeout = gpr_inf_future(GPR_TIMESPAN);
       }
       grpc_mdelem_set_user_data(md, free_timeout, cached_timeout);
     }
diff --git a/src/core/transport/chttp2/stream_lists.c b/src/core/transport/chttp2/stream_lists.c
index a81ffcce79..49f951d08b 100644
--- a/src/core/transport/chttp2/stream_lists.c
+++ b/src/core/transport/chttp2/stream_lists.c
@@ -108,23 +108,6 @@ static void stream_list_maybe_remove(grpc_chttp2_transport *t,
   }
 }
 
-static void stream_list_add_head(grpc_chttp2_transport *t,
-                                 grpc_chttp2_stream *s,
-                                 grpc_chttp2_stream_list_id id) {
-  grpc_chttp2_stream *old_head;
-  GPR_ASSERT(!s->included[id]);
-  old_head = t->lists[id].head;
-  s->links[id].next = old_head;
-  s->links[id].prev = NULL;
-  if (old_head) {
-    old_head->links[id].prev = s;
-  } else {
-    t->lists[id].tail = s;
-  }
-  t->lists[id].head = s;
-  s->included[id] = 1;
-}
-
 static void stream_list_add_tail(grpc_chttp2_transport *t,
                                  grpc_chttp2_stream *s,
                                  grpc_chttp2_stream_list_id id) {
@@ -161,15 +144,6 @@ void grpc_chttp2_list_add_writable_stream(
                   STREAM_FROM_GLOBAL(stream_global), GRPC_CHTTP2_LIST_WRITABLE);
 }
 
-void grpc_chttp2_list_add_first_writable_stream(
-    grpc_chttp2_transport_global *transport_global,
-    grpc_chttp2_stream_global *stream_global) {
-  GPR_ASSERT(stream_global->id != 0);
-  stream_list_add_head(TRANSPORT_FROM_GLOBAL(transport_global),
-                       STREAM_FROM_GLOBAL(stream_global),
-                       GRPC_CHTTP2_LIST_WRITABLE);
-}
-
 int grpc_chttp2_list_pop_writable_stream(
     grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_transport_writing *transport_writing,
@@ -379,6 +353,26 @@ int grpc_chttp2_list_pop_closed_waiting_for_parsing(
   return r;
 }
 
+void grpc_chttp2_list_add_closed_waiting_for_writing(
+    grpc_chttp2_transport_global *transport_global,
+    grpc_chttp2_stream_global *stream_global) {
+  stream_list_add(TRANSPORT_FROM_GLOBAL(transport_global),
+                  STREAM_FROM_GLOBAL(stream_global),
+                  GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_WRITING);
+}
+
+int grpc_chttp2_list_pop_closed_waiting_for_writing(
+    grpc_chttp2_transport_global *transport_global,
+    grpc_chttp2_stream_global **stream_global) {
+  grpc_chttp2_stream *stream;
+  int r = stream_list_pop(TRANSPORT_FROM_GLOBAL(transport_global), &stream,
+                          GRPC_CHTTP2_LIST_CLOSED_WAITING_FOR_WRITING);
+  if (r != 0) {
+    *stream_global = &stream->global;
+  }
+  return r;
+}
+
 void grpc_chttp2_register_stream(grpc_chttp2_transport *t,
                                  grpc_chttp2_stream *s) {
   stream_list_add_tail(t, s, GRPC_CHTTP2_LIST_ALL_STREAMS);
diff --git a/src/core/transport/chttp2/timeout_encoding.c b/src/core/transport/chttp2/timeout_encoding.c
index 8a9b290ecb..7ec8b4e8bf 100644
--- a/src/core/transport/chttp2/timeout_encoding.c
+++ b/src/core/transport/chttp2/timeout_encoding.c
@@ -36,14 +36,15 @@
 #include <stdio.h>
 #include <string.h>
 
+#include <grpc/support/port_platform.h>
 #include "src/core/support/string.h"
 
-static int round_up(int x, int divisor) {
+static gpr_int64 round_up(gpr_int64 x, gpr_int64 divisor) {
   return (x / divisor + (x % divisor != 0)) * divisor;
 }
 
 /* round an integer up to the next value with three significant figures */
-static int round_up_to_three_sig_figs(int x) {
+static gpr_int64 round_up_to_three_sig_figs(gpr_int64 x) {
   if (x < 1000) return x;
   if (x < 10000) return round_up(x, 10);
   if (x < 100000) return round_up(x, 100);
@@ -57,13 +58,13 @@ static int round_up_to_three_sig_figs(int x) {
 /* encode our minimum viable timeout value */
 static void enc_tiny(char *buffer) { memcpy(buffer, "1n", 3); }
 
-static void enc_ext(char *buffer, long value, char ext) {
-  int n = gpr_ltoa(value, buffer);
+static void enc_ext(char *buffer, gpr_int64 value, char ext) {
+  int n = gpr_int64toa(value, buffer);
   buffer[n] = ext;
   buffer[n + 1] = 0;
 }
 
-static void enc_seconds(char *buffer, long sec) {
+static void enc_seconds(char *buffer, gpr_int64 sec) {
   if (sec % 3600 == 0) {
     enc_ext(buffer, sec / 3600, 'H');
   } else if (sec % 60 == 0) {
@@ -73,7 +74,7 @@ static void enc_seconds(char *buffer, long sec) {
   }
 }
 
-static void enc_nanos(char *buffer, int x) {
+static void enc_nanos(char *buffer, gpr_int64 x) {
   x = round_up_to_three_sig_figs(x);
   if (x < 100000) {
     if (x % 1000 == 0) {
@@ -97,7 +98,7 @@ static void enc_nanos(char *buffer, int x) {
   }
 }
 
-static void enc_micros(char *buffer, int x) {
+static void enc_micros(char *buffer, gpr_int64 x) {
   x = round_up_to_three_sig_figs(x);
   if (x < 100000) {
     if (x % 1000 == 0) {
@@ -123,7 +124,7 @@ void grpc_chttp2_encode_timeout(gpr_timespec timeout, char *buffer) {
     enc_nanos(buffer, timeout.tv_nsec);
   } else if (timeout.tv_sec < 1000 && timeout.tv_nsec != 0) {
     enc_micros(buffer,
-               (int)(timeout.tv_sec * 1000000) +
+               (gpr_int64)(timeout.tv_sec * 1000000) +
                    (timeout.tv_nsec / 1000 + (timeout.tv_nsec % 1000 != 0)));
   } else {
     enc_seconds(buffer, timeout.tv_sec + (timeout.tv_nsec != 0));
diff --git a/src/core/transport/chttp2/varint.h b/src/core/transport/chttp2/varint.h
index 4dfcc76773..5acb15d032 100644
--- a/src/core/transport/chttp2/varint.h
+++ b/src/core/transport/chttp2/varint.h
@@ -50,7 +50,8 @@ void grpc_chttp2_hpack_write_varint_tail(gpr_uint32 tail_value,
 /* maximum value that can be bitpacked with the opcode if the opcode has a
    prefix
    of length prefix_bits */
-#define GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits) ((1 << (8 - (prefix_bits))) - 1)
+#define GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits) \
+  ((gpr_uint32)((1 << (8 - (prefix_bits))) - 1))
 
 /* length required to bitpack a value */
 #define GRPC_CHTTP2_VARINT_LENGTH(n, prefix_bits) \
@@ -65,7 +66,8 @@ void grpc_chttp2_hpack_write_varint_tail(gpr_uint32 tail_value,
     if ((length) == 1u) {                                                     \
       (tgt)[0] = (gpr_uint8)((prefix_or) | (n));                              \
     } else {                                                                  \
-      (tgt)[0] = (prefix_or) | GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits);        \
+      (tgt)[0] =                                                              \
+          (prefix_or) | (gpr_uint8)GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits);    \
       grpc_chttp2_hpack_write_varint_tail(                                    \
           (n)-GRPC_CHTTP2_MAX_IN_PREFIX(prefix_bits), (tgt) + 1, (length)-1); \
     }                                                                         \
diff --git a/src/core/transport/chttp2/writing.c b/src/core/transport/chttp2/writing.c
index 805d05222d..b5ca42d69c 100644
--- a/src/core/transport/chttp2/writing.c
+++ b/src/core/transport/chttp2/writing.c
@@ -332,17 +332,12 @@ void grpc_chttp2_cleanup_writing(
 
   while (grpc_chttp2_list_pop_written_stream(
       transport_global, transport_writing, &stream_global, &stream_writing)) {
-    if (stream_writing->sent_trailing_metadata) {
-      grpc_chttp2_mark_stream_closed(exec_ctx, transport_global, stream_global,
-                                     !transport_global->is_client, 1);
-    }
     if (stream_writing->sent_initial_metadata) {
       grpc_chttp2_complete_closure_step(
           exec_ctx, &stream_global->send_initial_metadata_finished, 1);
     }
     if (stream_writing->sent_message) {
       GPR_ASSERT(stream_writing->send_message == NULL);
-      GPR_ASSERT(stream_global->send_message_finished);
       grpc_chttp2_complete_closure_step(
           exec_ctx, &stream_global->send_message_finished, 1);
       stream_writing->sent_message = 0;
@@ -351,6 +346,10 @@ void grpc_chttp2_cleanup_writing(
       grpc_chttp2_complete_closure_step(
           exec_ctx, &stream_global->send_trailing_metadata_finished, 1);
     }
+    if (stream_writing->sent_trailing_metadata) {
+      grpc_chttp2_mark_stream_closed(exec_ctx, transport_global, stream_global,
+                                     !transport_global->is_client, 1);
+    }
     GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2_writing");
   }
   gpr_slice_buffer_reset_and_unref(&transport_writing->outbuf);
diff --git a/src/core/transport/chttp2_transport.c b/src/core/transport/chttp2_transport.c
index 3e88f69abf..c3847bb6c5 100644
--- a/src/core/transport/chttp2_transport.c
+++ b/src/core/transport/chttp2_transport.c
@@ -134,6 +134,9 @@ static void connectivity_state_set(
 static void check_read_ops(grpc_exec_ctx *exec_ctx,
                            grpc_chttp2_transport_global *transport_global);
 
+static void fail_pending_writes(grpc_exec_ctx *exec_ctx, 
+                                grpc_chttp2_stream_global *stream_global);
+
 /*
  * CONSTRUCTION/DESTRUCTION/REFCOUNTING
  */
@@ -625,6 +628,7 @@ void grpc_chttp2_terminate_writing(grpc_exec_ctx *exec_ctx,
                                    void *transport_writing_ptr, int success) {
   grpc_chttp2_transport_writing *transport_writing = transport_writing_ptr;
   grpc_chttp2_transport *t = TRANSPORT_FROM_WRITING(transport_writing);
+  grpc_chttp2_stream_global *stream_global;
 
   GPR_TIMER_BEGIN("grpc_chttp2_terminate_writing", 0);
 
@@ -638,6 +642,11 @@ void grpc_chttp2_terminate_writing(grpc_exec_ctx *exec_ctx,
 
   grpc_chttp2_cleanup_writing(exec_ctx, &t->global, &t->writing);
 
+  while (grpc_chttp2_list_pop_closed_waiting_for_writing(&t->global, &stream_global)) {
+    fail_pending_writes(exec_ctx, stream_global);
+    GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "finish_writes");
+  }
+
   /* leave the writing flag up on shutdown to prevent further writes in unlock()
      from starting */
   t->writing_active = 0;
@@ -901,6 +910,26 @@ static void send_ping_locked(grpc_chttp2_transport *t, grpc_closure *on_recv) {
   gpr_slice_buffer_add(&t->global.qbuf, grpc_chttp2_ping_create(0, p->id));
 }
 
+void grpc_chttp2_ack_ping(grpc_exec_ctx *exec_ctx,
+                          grpc_chttp2_transport_parsing *transport_parsing,
+                          const gpr_uint8 *opaque_8bytes) {
+  grpc_chttp2_outstanding_ping *ping;
+  grpc_chttp2_transport *t = TRANSPORT_FROM_PARSING(transport_parsing);
+  grpc_chttp2_transport_global *transport_global = &t->global;
+  lock(t);
+  for (ping = transport_global->pings.next; ping != &transport_global->pings;
+       ping = ping->next) {
+    if (0 == memcmp(opaque_8bytes, ping->id, 8)) {
+      grpc_exec_ctx_enqueue(exec_ctx, ping->on_recv, 1);
+      ping->next->prev = ping->prev;
+      ping->prev->next = ping->next;
+      gpr_free(ping);
+      break;
+    }
+  }
+  unlock(exec_ctx, t);
+}
+
 static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
                                  grpc_transport_op *op) {
   grpc_chttp2_transport *t = (grpc_chttp2_transport *)gt;
@@ -910,7 +939,7 @@ static void perform_transport_op(grpc_exec_ctx *exec_ctx, grpc_transport *gt,
 
   grpc_exec_ctx_enqueue(exec_ctx, op->on_consumed, 1);
 
-  if (op->on_connectivity_state_change) {
+  if (op->on_connectivity_state_change != NULL) {
     grpc_connectivity_state_notify_on_state_change(
         exec_ctx, &t->channel_callback.state_tracker, op->connectivity_state,
         op->on_connectivity_state_change);
@@ -1020,6 +1049,12 @@ static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     t->parsing.incoming_stream = NULL;
     grpc_chttp2_parsing_become_skip_parser(exec_ctx, &t->parsing);
   }
+  if (s->parsing.data_parser.parsing_frame != NULL) {
+    grpc_chttp2_incoming_byte_stream_finished(
+        exec_ctx, s->parsing.data_parser.parsing_frame, 0, 0);
+    s->parsing.data_parser.parsing_frame = NULL;
+  }
+
   if (grpc_chttp2_unregister_stream(t, s) && t->global.sent_goaway) {
     close_transport_locked(exec_ctx, t);
   }
@@ -1087,6 +1122,16 @@ void grpc_chttp2_fake_status(grpc_exec_ctx *exec_ctx,
   }
 }
 
+static void fail_pending_writes(grpc_exec_ctx *exec_ctx, 
+                                grpc_chttp2_stream_global *stream_global) {
+  grpc_chttp2_complete_closure_step(
+      exec_ctx, &stream_global->send_initial_metadata_finished, 0);
+  grpc_chttp2_complete_closure_step(
+      exec_ctx, &stream_global->send_trailing_metadata_finished, 0);
+  grpc_chttp2_complete_closure_step(exec_ctx,
+                                    &stream_global->send_message_finished, 0);
+}
+
 void grpc_chttp2_mark_stream_closed(
     grpc_exec_ctx *exec_ctx, grpc_chttp2_transport_global *transport_global,
     grpc_chttp2_stream_global *stream_global, int close_reads,
@@ -1103,6 +1148,13 @@ void grpc_chttp2_mark_stream_closed(
   }
   if (close_writes && !stream_global->write_closed) {
     stream_global->write_closed = 1;
+    if (TRANSPORT_FROM_GLOBAL(transport_global)->writing_active) {
+      GRPC_CHTTP2_STREAM_REF(stream_global, "finish_writes");
+      grpc_chttp2_list_add_closed_waiting_for_writing(transport_global,
+                                                      stream_global);
+    } else {
+      fail_pending_writes(exec_ctx, stream_global);
+    }
   }
   if (stream_global->read_closed && stream_global->write_closed) {
     if (stream_global->id != 0 &&
@@ -1114,7 +1166,6 @@ void grpc_chttp2_mark_stream_closed(
         remove_stream(exec_ctx, TRANSPORT_FROM_GLOBAL(transport_global),
                       stream_global->id);
       }
-      stream_global->finished_close = 1;
       GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2");
     }
   }
@@ -1328,7 +1379,6 @@ static void recv_data(grpc_exec_ctx *exec_ctx, void *tp, int success) {
       GPR_ASSERT(stream_global->write_closed);
       GPR_ASSERT(stream_global->read_closed);
       remove_stream(exec_ctx, t, stream_global->id);
-      stream_global->finished_close = 1;
       GRPC_CHTTP2_STREAM_UNREF(exec_ctx, stream_global, "chttp2");
     }
   }
@@ -1459,6 +1509,10 @@ static int incoming_byte_stream_next(grpc_exec_ctx *exec_ctx,
     *slice = gpr_slice_buffer_take_first(&bs->slices);
     unlock(exec_ctx, bs->transport);
     return 1;
+  } else if (bs->failed) {
+    grpc_exec_ctx_enqueue(exec_ctx, on_complete, 0);
+    unlock(exec_ctx, bs->transport);
+    return 0;
   } else {
     bs->on_next = on_complete;
     bs->next = slice;
@@ -1493,7 +1547,29 @@ void grpc_chttp2_incoming_byte_stream_push(grpc_exec_ctx *exec_ctx,
 }
 
 void grpc_chttp2_incoming_byte_stream_finished(
-    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs) {
+    grpc_exec_ctx *exec_ctx, grpc_chttp2_incoming_byte_stream *bs, int success,
+    int from_parsing_thread) {
+  if (!success) {
+    if (from_parsing_thread) {
+      gpr_mu_lock(&bs->transport->mu);
+    }
+    grpc_exec_ctx_enqueue(exec_ctx, bs->on_next, 0);
+    bs->on_next = NULL;
+    bs->failed = 1;
+    if (from_parsing_thread) {
+      gpr_mu_unlock(&bs->transport->mu);
+    }
+  } else {
+#ifndef NDEBUG
+    if (from_parsing_thread) {
+      gpr_mu_lock(&bs->transport->mu);
+    }
+    GPR_ASSERT(bs->on_next == NULL);
+    if (from_parsing_thread) {
+      gpr_mu_unlock(&bs->transport->mu);
+    }
+#endif
+  }
   incoming_byte_stream_unref(bs);
 }
 
@@ -1514,6 +1590,7 @@ grpc_chttp2_incoming_byte_stream *grpc_chttp2_incoming_byte_stream_create(
   gpr_slice_buffer_init(&incoming_byte_stream->slices);
   incoming_byte_stream->on_next = NULL;
   incoming_byte_stream->is_tail = 1;
+  incoming_byte_stream->failed = 0;
   if (add_to_queue->head == NULL) {
     add_to_queue->head = incoming_byte_stream;
   } else {
diff --git a/src/core/transport/connectivity_state.c b/src/core/transport/connectivity_state.c
index 09b298c131..3c3fd4671d 100644
--- a/src/core/transport/connectivity_state.c
+++ b/src/core/transport/connectivity_state.c
@@ -54,8 +54,7 @@ const char *grpc_connectivity_state_name(grpc_connectivity_state state) {
     case GRPC_CHANNEL_FATAL_FAILURE:
       return "FATAL_FAILURE";
   }
-  abort();
-  return "UNKNOWN";
+  GPR_UNREACHABLE_CODE(return "UNKNOWN");
 }
 
 void grpc_connectivity_state_init(grpc_connectivity_state_tracker *tracker,
@@ -88,7 +87,7 @@ void grpc_connectivity_state_destroy(grpc_exec_ctx *exec_ctx,
 grpc_connectivity_state grpc_connectivity_state_check(
     grpc_connectivity_state_tracker *tracker) {
   if (grpc_connectivity_state_trace) {
-    gpr_log(GPR_DEBUG, "CONWATCH: %s: get %s", tracker->name,
+    gpr_log(GPR_DEBUG, "CONWATCH: %p %s: get %s", tracker, tracker->name,
             grpc_connectivity_state_name(tracker->current_state));
   }
   return tracker->current_state;
@@ -98,42 +97,47 @@ int grpc_connectivity_state_notify_on_state_change(
     grpc_exec_ctx *exec_ctx, grpc_connectivity_state_tracker *tracker,
     grpc_connectivity_state *current, grpc_closure *notify) {
   if (grpc_connectivity_state_trace) {
-    gpr_log(GPR_DEBUG, "CONWATCH: %s: from %s [cur=%s] notify=%p",
-            tracker->name, grpc_connectivity_state_name(*current),
-            grpc_connectivity_state_name(tracker->current_state), notify);
+    if (current == NULL) {
+      gpr_log(GPR_DEBUG, "CONWATCH: %p %s: unsubscribe notify=%p", tracker,
+              tracker->name, notify);
+    } else {
+      gpr_log(GPR_DEBUG, "CONWATCH: %p %s: from %s [cur=%s] notify=%p", tracker,
+              tracker->name, grpc_connectivity_state_name(*current),
+              grpc_connectivity_state_name(tracker->current_state), notify);
+    }
   }
-  if (tracker->current_state != *current) {
-    *current = tracker->current_state;
-    grpc_exec_ctx_enqueue(exec_ctx, notify, 1);
+  if (current == NULL) {
+    grpc_connectivity_state_watcher *w = tracker->watchers;
+    if (w != NULL && w->notify == notify) {
+      grpc_exec_ctx_enqueue(exec_ctx, notify, 0);
+      tracker->watchers = w->next;
+      gpr_free(w);
+      return 0;
+    }
+    while (w != NULL) {
+      grpc_connectivity_state_watcher *rm_candidate = w->next;
+      if (rm_candidate != NULL && rm_candidate->notify == notify) {
+        grpc_exec_ctx_enqueue(exec_ctx, notify, 0);
+        w->next = w->next->next;
+        gpr_free(rm_candidate);
+        return 0;
+      }
+      w = w->next;
+    }
+    return 0;
   } else {
-    grpc_connectivity_state_watcher *w = gpr_malloc(sizeof(*w));
-    w->current = current;
-    w->notify = notify;
-    w->next = tracker->watchers;
-    tracker->watchers = w;
-  }
-  return tracker->current_state == GRPC_CHANNEL_IDLE;
-}
-
-int grpc_connectivity_state_change_unsubscribe(
-    grpc_exec_ctx *exec_ctx, grpc_connectivity_state_tracker *tracker,
-    grpc_closure *subscribed_notify) {
-  grpc_connectivity_state_watcher *w = tracker->watchers;
-  if (w != NULL && w->notify == subscribed_notify) {
-    tracker->watchers = w->next;
-    gpr_free(w);
-    return 1;
-  }
-  while (w != NULL) {
-    grpc_connectivity_state_watcher *rm_candidate = w->next;
-    if (rm_candidate != NULL && rm_candidate->notify == subscribed_notify) {
-      w->next = w->next->next;
-      gpr_free(rm_candidate);
-      return 1;
+    if (tracker->current_state != *current) {
+      *current = tracker->current_state;
+      grpc_exec_ctx_enqueue(exec_ctx, notify, 1);
+    } else {
+      grpc_connectivity_state_watcher *w = gpr_malloc(sizeof(*w));
+      w->current = current;
+      w->notify = notify;
+      w->next = tracker->watchers;
+      tracker->watchers = w;
     }
-    w = w->next;
+    return tracker->current_state == GRPC_CHANNEL_IDLE;
   }
-  return 0;
 }
 
 void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
@@ -142,7 +146,7 @@ void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
                                  const char *reason) {
   grpc_connectivity_state_watcher *w;
   if (grpc_connectivity_state_trace) {
-    gpr_log(GPR_DEBUG, "SET: %s: %s --> %s [%s]", tracker->name,
+    gpr_log(GPR_DEBUG, "SET: %p %s: %s --> %s [%s]", tracker, tracker->name,
             grpc_connectivity_state_name(tracker->current_state),
             grpc_connectivity_state_name(state), reason);
   }
diff --git a/src/core/transport/connectivity_state.h b/src/core/transport/connectivity_state.h
index 119b1c1554..a4eb6652e5 100644
--- a/src/core/transport/connectivity_state.h
+++ b/src/core/transport/connectivity_state.h
@@ -57,6 +57,8 @@ typedef struct {
 
 extern int grpc_connectivity_state_trace;
 
+const char *grpc_connectivity_state_name(grpc_connectivity_state state);
+
 void grpc_connectivity_state_init(grpc_connectivity_state_tracker *tracker,
                                   grpc_connectivity_state init_state,
                                   const char *name);
@@ -73,16 +75,11 @@ void grpc_connectivity_state_set(grpc_exec_ctx *exec_ctx,
 grpc_connectivity_state grpc_connectivity_state_check(
     grpc_connectivity_state_tracker *tracker);
 
-/** Return 1 if the channel should start connecting, 0 otherwise */
+/** Return 1 if the channel should start connecting, 0 otherwise.
+    If current==NULL cancel notify if it is already queued (success==0 in that
+    case) */
 int grpc_connectivity_state_notify_on_state_change(
     grpc_exec_ctx *exec_ctx, grpc_connectivity_state_tracker *tracker,
     grpc_connectivity_state *current, grpc_closure *notify);
 
-/** Remove \a subscribed_notify from the list of closures to be called on a
- * state change if present, returning 1. Otherwise, nothing is done and return
- * 0. */
-int grpc_connectivity_state_change_unsubscribe(
-    grpc_exec_ctx *exec_ctx, grpc_connectivity_state_tracker *tracker,
-    grpc_closure *subscribed_notify);
-
 #endif /* GRPC_INTERNAL_CORE_TRANSPORT_CONNECTIVITY_STATE_H */
diff --git a/src/core/transport/metadata.c b/src/core/transport/metadata.c
index d6fb255eb6..02b2402820 100644
--- a/src/core/transport/metadata.c
+++ b/src/core/transport/metadata.c
@@ -225,7 +225,8 @@ void grpc_mdctx_global_shutdown(void) {
     gc_mdtab(shard);
     /* TODO(ctiller): GPR_ASSERT(shard->count == 0); */
     if (shard->count != 0) {
-      gpr_log(GPR_DEBUG, "WARNING: %d metadata elements were leaked", shard->count);
+      gpr_log(GPR_DEBUG, "WARNING: %d metadata elements were leaked",
+              shard->count);
     }
     gpr_free(shard->elems);
   }
@@ -234,7 +235,8 @@ void grpc_mdctx_global_shutdown(void) {
     gpr_mu_destroy(&shard->mu);
     /* TODO(ctiller): GPR_ASSERT(shard->count == 0); */
     if (shard->count != 0) {
-      gpr_log(GPR_DEBUG, "WARNING: %d metadata strings were leaked", shard->count);
+      gpr_log(GPR_DEBUG, "WARNING: %d metadata strings were leaked",
+              shard->count);
     }
     gpr_free(shard->strs);
   }
@@ -701,7 +703,7 @@ static int conforms_to(grpc_mdstr *s, const gpr_uint8 *legal_bits) {
 
 int grpc_mdstr_is_legal_header(grpc_mdstr *s) {
   static const gpr_uint8 legal_header_bits[256 / 8] = {
-      0x00, 0x00, 0x00, 0x00, 0x00, 0x20, 0xff, 0x03, 0x00, 0x00, 0x00,
+      0x00, 0x00, 0x00, 0x00, 0x00, 0x60, 0xff, 0x03, 0x00, 0x00, 0x00,
       0x80, 0xfe, 0xff, 0xff, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
   return conforms_to(s, legal_header_bits);
@@ -709,7 +711,7 @@ int grpc_mdstr_is_legal_header(grpc_mdstr *s) {
 
 int grpc_mdstr_is_legal_nonbin_header(grpc_mdstr *s) {
   static const gpr_uint8 legal_header_bits[256 / 8] = {
-      0x00, 0x00, 0x00, 0x00, 0xff, 0xef, 0xff, 0xff, 0xff, 0xff, 0xff,
+      0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
       0xff, 0xff, 0xff, 0xff, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
   return conforms_to(s, legal_header_bits);
diff --git a/src/core/transport/metadata_batch.c b/src/core/transport/metadata_batch.c
index c5d39e0c9f..1266862f82 100644
--- a/src/core/transport/metadata_batch.c
+++ b/src/core/transport/metadata_batch.c
@@ -133,16 +133,6 @@ void grpc_metadata_batch_link_tail(grpc_metadata_batch *batch,
   link_tail(&batch->list, storage);
 }
 
-void grpc_metadata_batch_merge(grpc_metadata_batch *target,
-                               grpc_metadata_batch *to_add) {
-  grpc_linked_mdelem *l;
-  grpc_linked_mdelem *next;
-  for (l = to_add->list.head; l; l = next) {
-    next = l->next;
-    link_tail(&target->list, l);
-  }
-}
-
 void grpc_metadata_batch_move(grpc_metadata_batch *dst,
                               grpc_metadata_batch *src) {
   *dst = *src;
diff --git a/src/core/transport/metadata_batch.h b/src/core/transport/metadata_batch.h
index fc3a46004f..1b0d1fda3e 100644
--- a/src/core/transport/metadata_batch.h
+++ b/src/core/transport/metadata_batch.h
@@ -63,8 +63,6 @@ typedef struct grpc_metadata_batch {
 
 void grpc_metadata_batch_init(grpc_metadata_batch *batch);
 void grpc_metadata_batch_destroy(grpc_metadata_batch *batch);
-void grpc_metadata_batch_merge(grpc_metadata_batch *target,
-                               grpc_metadata_batch *add);
 void grpc_metadata_batch_clear(grpc_metadata_batch *batch);
 int grpc_metadata_batch_is_empty(grpc_metadata_batch *batch);
 
diff --git a/src/core/transport/static_metadata.c b/src/core/transport/static_metadata.c
index e7aff325c2..6e42379eee 100644
--- a/src/core/transport/static_metadata.c
+++ b/src/core/transport/static_metadata.c
@@ -33,11 +33,11 @@
  * WARNING: Auto-generated code.
  *
  * To make changes to this file, change
- * tools/codegen/core/gen_static_metadata.py,
+ *tools/codegen/core/gen_static_metadata.py,
  * and then re-run it.
  *
  * See metadata.h for an explanation of the interface here, and metadata.c for
- * an
+ *an
  * explanation of what's going on.
  */
 
@@ -54,103 +54,34 @@ gpr_uintptr grpc_static_mdelem_user_data[GRPC_STATIC_MDELEM_COUNT] = {
 
 const gpr_uint8
     grpc_static_metadata_elem_indices[GRPC_STATIC_MDELEM_COUNT * 2] = {
-        11, 33, 10, 33, 12, 33, 12, 47, 13, 33, 14, 33, 15, 33, 16, 33, 17, 33,
-        19, 33, 20, 33, 21, 33, 22, 33, 23, 33, 24, 33, 25, 33, 26, 33, 27, 33,
-        28, 18, 28, 33, 29, 33, 30, 33, 34, 33, 35, 33, 36, 33, 37, 33, 40, 31,
-        40, 32, 40, 46, 40, 51, 40, 52, 40, 53, 40, 54, 41, 31, 41, 46, 41, 51,
-        44, 0,  44, 1,  44, 2,  48, 33, 55, 33, 56, 33, 57, 33, 58, 33, 59, 33,
-        60, 33, 61, 33, 62, 33, 63, 33, 64, 38, 64, 66, 65, 76, 65, 77, 67, 33,
-        68, 33, 69, 33, 70, 33, 71, 33, 72, 33, 73, 39, 73, 49, 73, 50, 74, 33,
-        75, 33, 78, 3,  78, 4,  78, 5,  78, 6,  78, 7,  78, 8,  78, 9,  79, 33,
-        80, 81, 82, 33, 83, 33, 84, 33, 85, 33, 86, 33};
+        11, 35, 10, 35, 12, 35, 12, 49, 13, 35, 14, 35, 15, 35, 16, 35, 17, 35,
+        19, 35, 20, 35, 21, 35, 24, 35, 25, 35, 26, 35, 27, 35, 28, 35, 29, 35,
+        30, 18, 30, 35, 31, 35, 32, 35, 36, 35, 37, 35, 38, 35, 39, 35, 42, 33,
+        42, 34, 42, 48, 42, 53, 42, 54, 42, 55, 42, 56, 43, 33, 43, 48, 43, 53,
+        46, 0,  46, 1,  46, 2,  50, 35, 57, 35, 58, 35, 59, 35, 60, 35, 61, 35,
+        62, 35, 63, 35, 64, 35, 65, 35, 66, 40, 66, 68, 67, 78, 67, 79, 69, 35,
+        70, 35, 71, 35, 72, 35, 73, 35, 74, 35, 75, 41, 75, 51, 75, 52, 76, 35,
+        77, 35, 80, 3,  80, 4,  80, 5,  80, 6,  80, 7,  80, 8,  80, 9,  81, 35,
+        82, 83, 84, 35, 85, 35, 86, 35, 87, 35, 88, 35};
 
 const char *const grpc_static_metadata_strings[GRPC_STATIC_MDSTR_COUNT] = {
-    "0",
-    "1",
-    "2",
-    "200",
-    "204",
-    "206",
-    "304",
-    "400",
-    "404",
-    "500",
-    "accept",
-    "accept-charset",
-    "accept-encoding",
-    "accept-language",
-    "accept-ranges",
-    "access-control-allow-origin",
-    "age",
-    "allow",
-    "application/grpc",
-    ":authority",
-    "authorization",
-    "cache-control",
-    "content-disposition",
-    "content-encoding",
-    "content-language",
-    "content-length",
-    "content-location",
-    "content-range",
-    "content-type",
-    "cookie",
-    "date",
-    "deflate",
-    "deflate,gzip",
-    "",
-    "etag",
-    "expect",
-    "expires",
-    "from",
-    "GET",
-    "grpc",
-    "grpc-accept-encoding",
-    "grpc-encoding",
-    "grpc-internal-encoding-request",
-    "grpc-message",
-    "grpc-status",
-    "grpc-timeout",
-    "gzip",
-    "gzip, deflate",
-    "host",
-    "http",
-    "https",
-    "identity",
-    "identity,deflate",
-    "identity,deflate,gzip",
-    "identity,gzip",
-    "if-match",
-    "if-modified-since",
-    "if-none-match",
-    "if-range",
-    "if-unmodified-since",
-    "last-modified",
-    "link",
-    "location",
-    "max-forwards",
-    ":method",
-    ":path",
-    "POST",
-    "proxy-authenticate",
-    "proxy-authorization",
-    "range",
-    "referer",
-    "refresh",
-    "retry-after",
-    ":scheme",
-    "server",
-    "set-cookie",
-    "/",
-    "/index.html",
-    ":status",
-    "strict-transport-security",
-    "te",
-    "trailers",
-    "transfer-encoding",
-    "user-agent",
-    "vary",
-    "via",
+    "0", "1", "2", "200", "204", "206", "304", "400", "404", "500", "accept",
+    "accept-charset", "accept-encoding", "accept-language", "accept-ranges",
+    "access-control-allow-origin", "age", "allow", "application/grpc",
+    ":authority", "authorization", "cache-control", "census", "census-bin",
+    "content-disposition", "content-encoding", "content-language",
+    "content-length", "content-location", "content-range", "content-type",
+    "cookie", "date", "deflate", "deflate,gzip", "", "etag", "expect",
+    "expires", "from", "GET", "grpc", "grpc-accept-encoding", "grpc-encoding",
+    "grpc-internal-encoding-request", "grpc-message", "grpc-status",
+    "grpc-timeout", "gzip", "gzip, deflate", "host", "http", "https",
+    "identity", "identity,deflate", "identity,deflate,gzip", "identity,gzip",
+    "if-match", "if-modified-since", "if-none-match", "if-range",
+    "if-unmodified-since", "last-modified", "link", "location", "max-forwards",
+    ":method", ":path", "POST", "proxy-authenticate", "proxy-authorization",
+    "range", "referer", "refresh", "retry-after", ":scheme", "server",
+    "set-cookie", "/", "/index.html", ":status", "strict-transport-security",
+    "te", "trailers", "transfer-encoding", "user-agent", "vary", "via",
     "www-authenticate"};
 
 const gpr_uint8 grpc_static_accept_encoding_metadata[8] = {0,  29, 26, 30,
diff --git a/src/core/transport/static_metadata.h b/src/core/transport/static_metadata.h
index e9055fb45c..0e630b1b03 100644
--- a/src/core/transport/static_metadata.h
+++ b/src/core/transport/static_metadata.h
@@ -46,7 +46,7 @@
 
 #include "src/core/transport/metadata.h"
 
-#define GRPC_STATIC_MDSTR_COUNT 87
+#define GRPC_STATIC_MDSTR_COUNT 89
 extern grpc_mdstr grpc_static_mdstr_table[GRPC_STATIC_MDSTR_COUNT];
 /* "0" */
 #define GRPC_MDSTR_0 (&grpc_static_mdstr_table[0])
@@ -92,137 +92,141 @@ extern grpc_mdstr grpc_static_mdstr_table[GRPC_STATIC_MDSTR_COUNT];
 #define GRPC_MDSTR_AUTHORIZATION (&grpc_static_mdstr_table[20])
 /* "cache-control" */
 #define GRPC_MDSTR_CACHE_CONTROL (&grpc_static_mdstr_table[21])
+/* "census" */
+#define GRPC_MDSTR_CENSUS (&grpc_static_mdstr_table[22])
+/* "census-bin" */
+#define GRPC_MDSTR_CENSUS_BIN (&grpc_static_mdstr_table[23])
 /* "content-disposition" */
-#define GRPC_MDSTR_CONTENT_DISPOSITION (&grpc_static_mdstr_table[22])
+#define GRPC_MDSTR_CONTENT_DISPOSITION (&grpc_static_mdstr_table[24])
 /* "content-encoding" */
-#define GRPC_MDSTR_CONTENT_ENCODING (&grpc_static_mdstr_table[23])
+#define GRPC_MDSTR_CONTENT_ENCODING (&grpc_static_mdstr_table[25])
 /* "content-language" */
-#define GRPC_MDSTR_CONTENT_LANGUAGE (&grpc_static_mdstr_table[24])
+#define GRPC_MDSTR_CONTENT_LANGUAGE (&grpc_static_mdstr_table[26])
 /* "content-length" */
-#define GRPC_MDSTR_CONTENT_LENGTH (&grpc_static_mdstr_table[25])
+#define GRPC_MDSTR_CONTENT_LENGTH (&grpc_static_mdstr_table[27])
 /* "content-location" */
-#define GRPC_MDSTR_CONTENT_LOCATION (&grpc_static_mdstr_table[26])
+#define GRPC_MDSTR_CONTENT_LOCATION (&grpc_static_mdstr_table[28])
 /* "content-range" */
-#define GRPC_MDSTR_CONTENT_RANGE (&grpc_static_mdstr_table[27])
+#define GRPC_MDSTR_CONTENT_RANGE (&grpc_static_mdstr_table[29])
 /* "content-type" */
-#define GRPC_MDSTR_CONTENT_TYPE (&grpc_static_mdstr_table[28])
+#define GRPC_MDSTR_CONTENT_TYPE (&grpc_static_mdstr_table[30])
 /* "cookie" */
-#define GRPC_MDSTR_COOKIE (&grpc_static_mdstr_table[29])
+#define GRPC_MDSTR_COOKIE (&grpc_static_mdstr_table[31])
 /* "date" */
-#define GRPC_MDSTR_DATE (&grpc_static_mdstr_table[30])
+#define GRPC_MDSTR_DATE (&grpc_static_mdstr_table[32])
 /* "deflate" */
-#define GRPC_MDSTR_DEFLATE (&grpc_static_mdstr_table[31])
+#define GRPC_MDSTR_DEFLATE (&grpc_static_mdstr_table[33])
 /* "deflate,gzip" */
-#define GRPC_MDSTR_DEFLATE_COMMA_GZIP (&grpc_static_mdstr_table[32])
+#define GRPC_MDSTR_DEFLATE_COMMA_GZIP (&grpc_static_mdstr_table[34])
 /* "" */
-#define GRPC_MDSTR_EMPTY (&grpc_static_mdstr_table[33])
+#define GRPC_MDSTR_EMPTY (&grpc_static_mdstr_table[35])
 /* "etag" */
-#define GRPC_MDSTR_ETAG (&grpc_static_mdstr_table[34])
+#define GRPC_MDSTR_ETAG (&grpc_static_mdstr_table[36])
 /* "expect" */
-#define GRPC_MDSTR_EXPECT (&grpc_static_mdstr_table[35])
+#define GRPC_MDSTR_EXPECT (&grpc_static_mdstr_table[37])
 /* "expires" */
-#define GRPC_MDSTR_EXPIRES (&grpc_static_mdstr_table[36])
+#define GRPC_MDSTR_EXPIRES (&grpc_static_mdstr_table[38])
 /* "from" */
-#define GRPC_MDSTR_FROM (&grpc_static_mdstr_table[37])
+#define GRPC_MDSTR_FROM (&grpc_static_mdstr_table[39])
 /* "GET" */
-#define GRPC_MDSTR_GET (&grpc_static_mdstr_table[38])
+#define GRPC_MDSTR_GET (&grpc_static_mdstr_table[40])
 /* "grpc" */
-#define GRPC_MDSTR_GRPC (&grpc_static_mdstr_table[39])
+#define GRPC_MDSTR_GRPC (&grpc_static_mdstr_table[41])
 /* "grpc-accept-encoding" */
-#define GRPC_MDSTR_GRPC_ACCEPT_ENCODING (&grpc_static_mdstr_table[40])
+#define GRPC_MDSTR_GRPC_ACCEPT_ENCODING (&grpc_static_mdstr_table[42])
 /* "grpc-encoding" */
-#define GRPC_MDSTR_GRPC_ENCODING (&grpc_static_mdstr_table[41])
+#define GRPC_MDSTR_GRPC_ENCODING (&grpc_static_mdstr_table[43])
 /* "grpc-internal-encoding-request" */
-#define GRPC_MDSTR_GRPC_INTERNAL_ENCODING_REQUEST (&grpc_static_mdstr_table[42])
+#define GRPC_MDSTR_GRPC_INTERNAL_ENCODING_REQUEST (&grpc_static_mdstr_table[44])
 /* "grpc-message" */
-#define GRPC_MDSTR_GRPC_MESSAGE (&grpc_static_mdstr_table[43])
+#define GRPC_MDSTR_GRPC_MESSAGE (&grpc_static_mdstr_table[45])
 /* "grpc-status" */
-#define GRPC_MDSTR_GRPC_STATUS (&grpc_static_mdstr_table[44])
+#define GRPC_MDSTR_GRPC_STATUS (&grpc_static_mdstr_table[46])
 /* "grpc-timeout" */
-#define GRPC_MDSTR_GRPC_TIMEOUT (&grpc_static_mdstr_table[45])
+#define GRPC_MDSTR_GRPC_TIMEOUT (&grpc_static_mdstr_table[47])
 /* "gzip" */
-#define GRPC_MDSTR_GZIP (&grpc_static_mdstr_table[46])
+#define GRPC_MDSTR_GZIP (&grpc_static_mdstr_table[48])
 /* "gzip, deflate" */
-#define GRPC_MDSTR_GZIP_COMMA_DEFLATE (&grpc_static_mdstr_table[47])
+#define GRPC_MDSTR_GZIP_COMMA_DEFLATE (&grpc_static_mdstr_table[49])
 /* "host" */
-#define GRPC_MDSTR_HOST (&grpc_static_mdstr_table[48])
+#define GRPC_MDSTR_HOST (&grpc_static_mdstr_table[50])
 /* "http" */
-#define GRPC_MDSTR_HTTP (&grpc_static_mdstr_table[49])
+#define GRPC_MDSTR_HTTP (&grpc_static_mdstr_table[51])
 /* "https" */
-#define GRPC_MDSTR_HTTPS (&grpc_static_mdstr_table[50])
+#define GRPC_MDSTR_HTTPS (&grpc_static_mdstr_table[52])
 /* "identity" */
-#define GRPC_MDSTR_IDENTITY (&grpc_static_mdstr_table[51])
+#define GRPC_MDSTR_IDENTITY (&grpc_static_mdstr_table[53])
 /* "identity,deflate" */
-#define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE (&grpc_static_mdstr_table[52])
+#define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE (&grpc_static_mdstr_table[54])
 /* "identity,deflate,gzip" */
 #define GRPC_MDSTR_IDENTITY_COMMA_DEFLATE_COMMA_GZIP \
-  (&grpc_static_mdstr_table[53])
+  (&grpc_static_mdstr_table[55])
 /* "identity,gzip" */
-#define GRPC_MDSTR_IDENTITY_COMMA_GZIP (&grpc_static_mdstr_table[54])
+#define GRPC_MDSTR_IDENTITY_COMMA_GZIP (&grpc_static_mdstr_table[56])
 /* "if-match" */
-#define GRPC_MDSTR_IF_MATCH (&grpc_static_mdstr_table[55])
+#define GRPC_MDSTR_IF_MATCH (&grpc_static_mdstr_table[57])
 /* "if-modified-since" */
-#define GRPC_MDSTR_IF_MODIFIED_SINCE (&grpc_static_mdstr_table[56])
+#define GRPC_MDSTR_IF_MODIFIED_SINCE (&grpc_static_mdstr_table[58])
 /* "if-none-match" */
-#define GRPC_MDSTR_IF_NONE_MATCH (&grpc_static_mdstr_table[57])
+#define GRPC_MDSTR_IF_NONE_MATCH (&grpc_static_mdstr_table[59])
 /* "if-range" */
-#define GRPC_MDSTR_IF_RANGE (&grpc_static_mdstr_table[58])
+#define GRPC_MDSTR_IF_RANGE (&grpc_static_mdstr_table[60])
 /* "if-unmodified-since" */
-#define GRPC_MDSTR_IF_UNMODIFIED_SINCE (&grpc_static_mdstr_table[59])
+#define GRPC_MDSTR_IF_UNMODIFIED_SINCE (&grpc_static_mdstr_table[61])
 /* "last-modified" */
-#define GRPC_MDSTR_LAST_MODIFIED (&grpc_static_mdstr_table[60])
+#define GRPC_MDSTR_LAST_MODIFIED (&grpc_static_mdstr_table[62])
 /* "link" */
-#define GRPC_MDSTR_LINK (&grpc_static_mdstr_table[61])
+#define GRPC_MDSTR_LINK (&grpc_static_mdstr_table[63])
 /* "location" */
-#define GRPC_MDSTR_LOCATION (&grpc_static_mdstr_table[62])
+#define GRPC_MDSTR_LOCATION (&grpc_static_mdstr_table[64])
 /* "max-forwards" */
-#define GRPC_MDSTR_MAX_FORWARDS (&grpc_static_mdstr_table[63])
+#define GRPC_MDSTR_MAX_FORWARDS (&grpc_static_mdstr_table[65])
 /* ":method" */
-#define GRPC_MDSTR_METHOD (&grpc_static_mdstr_table[64])
+#define GRPC_MDSTR_METHOD (&grpc_static_mdstr_table[66])
 /* ":path" */
-#define GRPC_MDSTR_PATH (&grpc_static_mdstr_table[65])
+#define GRPC_MDSTR_PATH (&grpc_static_mdstr_table[67])
 /* "POST" */
-#define GRPC_MDSTR_POST (&grpc_static_mdstr_table[66])
+#define GRPC_MDSTR_POST (&grpc_static_mdstr_table[68])
 /* "proxy-authenticate" */
-#define GRPC_MDSTR_PROXY_AUTHENTICATE (&grpc_static_mdstr_table[67])
+#define GRPC_MDSTR_PROXY_AUTHENTICATE (&grpc_static_mdstr_table[69])
 /* "proxy-authorization" */
-#define GRPC_MDSTR_PROXY_AUTHORIZATION (&grpc_static_mdstr_table[68])
+#define GRPC_MDSTR_PROXY_AUTHORIZATION (&grpc_static_mdstr_table[70])
 /* "range" */
-#define GRPC_MDSTR_RANGE (&grpc_static_mdstr_table[69])
+#define GRPC_MDSTR_RANGE (&grpc_static_mdstr_table[71])
 /* "referer" */
-#define GRPC_MDSTR_REFERER (&grpc_static_mdstr_table[70])
+#define GRPC_MDSTR_REFERER (&grpc_static_mdstr_table[72])
 /* "refresh" */
-#define GRPC_MDSTR_REFRESH (&grpc_static_mdstr_table[71])
+#define GRPC_MDSTR_REFRESH (&grpc_static_mdstr_table[73])
 /* "retry-after" */
-#define GRPC_MDSTR_RETRY_AFTER (&grpc_static_mdstr_table[72])
+#define GRPC_MDSTR_RETRY_AFTER (&grpc_static_mdstr_table[74])
 /* ":scheme" */
-#define GRPC_MDSTR_SCHEME (&grpc_static_mdstr_table[73])
+#define GRPC_MDSTR_SCHEME (&grpc_static_mdstr_table[75])
 /* "server" */
-#define GRPC_MDSTR_SERVER (&grpc_static_mdstr_table[74])
+#define GRPC_MDSTR_SERVER (&grpc_static_mdstr_table[76])
 /* "set-cookie" */
-#define GRPC_MDSTR_SET_COOKIE (&grpc_static_mdstr_table[75])
+#define GRPC_MDSTR_SET_COOKIE (&grpc_static_mdstr_table[77])
 /* "/" */
-#define GRPC_MDSTR_SLASH (&grpc_static_mdstr_table[76])
+#define GRPC_MDSTR_SLASH (&grpc_static_mdstr_table[78])
 /* "/index.html" */
-#define GRPC_MDSTR_SLASH_INDEX_DOT_HTML (&grpc_static_mdstr_table[77])
+#define GRPC_MDSTR_SLASH_INDEX_DOT_HTML (&grpc_static_mdstr_table[79])
 /* ":status" */
-#define GRPC_MDSTR_STATUS (&grpc_static_mdstr_table[78])
+#define GRPC_MDSTR_STATUS (&grpc_static_mdstr_table[80])
 /* "strict-transport-security" */
-#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (&grpc_static_mdstr_table[79])
+#define GRPC_MDSTR_STRICT_TRANSPORT_SECURITY (&grpc_static_mdstr_table[81])
 /* "te" */
-#define GRPC_MDSTR_TE (&grpc_static_mdstr_table[80])
+#define GRPC_MDSTR_TE (&grpc_static_mdstr_table[82])
 /* "trailers" */
-#define GRPC_MDSTR_TRAILERS (&grpc_static_mdstr_table[81])
+#define GRPC_MDSTR_TRAILERS (&grpc_static_mdstr_table[83])
 /* "transfer-encoding" */
-#define GRPC_MDSTR_TRANSFER_ENCODING (&grpc_static_mdstr_table[82])
+#define GRPC_MDSTR_TRANSFER_ENCODING (&grpc_static_mdstr_table[84])
 /* "user-agent" */
-#define GRPC_MDSTR_USER_AGENT (&grpc_static_mdstr_table[83])
+#define GRPC_MDSTR_USER_AGENT (&grpc_static_mdstr_table[85])
 /* "vary" */
-#define GRPC_MDSTR_VARY (&grpc_static_mdstr_table[84])
+#define GRPC_MDSTR_VARY (&grpc_static_mdstr_table[86])
 /* "via" */
-#define GRPC_MDSTR_VIA (&grpc_static_mdstr_table[85])
+#define GRPC_MDSTR_VIA (&grpc_static_mdstr_table[87])
 /* "www-authenticate" */
-#define GRPC_MDSTR_WWW_AUTHENTICATE (&grpc_static_mdstr_table[86])
+#define GRPC_MDSTR_WWW_AUTHENTICATE (&grpc_static_mdstr_table[88])
 
 #define GRPC_STATIC_MDELEM_COUNT 78
 extern grpc_mdelem grpc_static_mdelem_table[GRPC_STATIC_MDELEM_COUNT];
diff --git a/src/core/transport/transport.c b/src/core/transport/transport.c
index f2bebc62f3..2ab978be46 100644
--- a/src/core/transport/transport.c
+++ b/src/core/transport/transport.c
@@ -40,8 +40,8 @@
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
 void grpc_stream_ref(grpc_stream_refcount *refcount, const char *reason) {
   gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
-  gpr_log(GPR_DEBUG, "STREAM %p:%p   REF %d->%d %s", refcount,
-          refcount->destroy.cb_arg, val, val + 1, reason);
+  gpr_log(GPR_DEBUG, "%s %p:%p   REF %d->%d %s", refcount->object_type,
+          refcount, refcount->destroy.cb_arg, val, val + 1, reason);
 #else
 void grpc_stream_ref(grpc_stream_refcount *refcount) {
 #endif
@@ -52,8 +52,8 @@ void grpc_stream_ref(grpc_stream_refcount *refcount) {
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx, grpc_stream_refcount *refcount,
                        const char *reason) {
   gpr_atm val = gpr_atm_no_barrier_load(&refcount->refs.count);
-  gpr_log(GPR_DEBUG, "STREAM %p:%p UNREF %d->%d %s", refcount,
-          refcount->destroy.cb_arg, val, val - 1, reason);
+  gpr_log(GPR_DEBUG, "%s %p:%p UNREF %d->%d %s", refcount->object_type,
+          refcount, refcount->destroy.cb_arg, val, val - 1, reason);
 #else
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx,
                        grpc_stream_refcount *refcount) {
@@ -63,6 +63,19 @@ void grpc_stream_unref(grpc_exec_ctx *exec_ctx,
   }
 }
 
+#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
+                          grpc_iomgr_cb_func cb, void *cb_arg,
+                          const char *object_type) {
+  refcount->object_type = object_type;
+#else
+void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
+                          grpc_iomgr_cb_func cb, void *cb_arg) {
+#endif
+  gpr_ref_init(&refcount->refs, initial_refs);
+  grpc_closure_init(&refcount->destroy, cb, cb_arg);
+}
+
 size_t grpc_transport_stream_size(grpc_transport *transport) {
   return transport->vtable->sizeof_stream;
 }
diff --git a/src/core/transport/transport.h b/src/core/transport/transport.h
index f296ce8251..f94f0ae76e 100644
--- a/src/core/transport/transport.h
+++ b/src/core/transport/transport.h
@@ -50,19 +50,32 @@ typedef struct grpc_transport grpc_transport;
    for a stream. */
 typedef struct grpc_stream grpc_stream;
 
+/*#define GRPC_STREAM_REFCOUNT_DEBUG*/
+
 typedef struct grpc_stream_refcount {
   gpr_refcount refs;
   grpc_closure destroy;
+#ifdef GRPC_STREAM_REFCOUNT_DEBUG
+  const char *object_type;
+#endif
 } grpc_stream_refcount;
 
-/*#define GRPC_STREAM_REFCOUNT_DEBUG*/
 #ifdef GRPC_STREAM_REFCOUNT_DEBUG
+void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
+                          grpc_iomgr_cb_func cb, void *cb_arg,
+                          const char *object_type);
 void grpc_stream_ref(grpc_stream_refcount *refcount, const char *reason);
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx, grpc_stream_refcount *refcount,
                        const char *reason);
+#define GRPC_STREAM_REF_INIT(rc, ir, cb, cb_arg, objtype) \
+  grpc_stream_ref_init(rc, ir, cb, cb_arg, objtype)
 #else
+void grpc_stream_ref_init(grpc_stream_refcount *refcount, int initial_refs,
+                          grpc_iomgr_cb_func cb, void *cb_arg);
 void grpc_stream_ref(grpc_stream_refcount *refcount);
 void grpc_stream_unref(grpc_exec_ctx *exec_ctx, grpc_stream_refcount *refcount);
+#define GRPC_STREAM_REF_INIT(rc, ir, cb, cb_arg, objtype) \
+  grpc_stream_ref_init(rc, ir, cb, cb_arg)
 #endif
 
 /* Transport stream op: a set of operations to perform on a transport
@@ -96,7 +109,7 @@ typedef struct grpc_transport_stream_op {
 typedef struct grpc_transport_op {
   /** called when processing of this op is done */
   grpc_closure *on_consumed;
-  /** connectivity monitoring */
+  /** connectivity monitoring - set connectivity_state to NULL to unsubscribe */
   grpc_closure *on_connectivity_state_change;
   grpc_connectivity_state *connectivity_state;
   /** should the transport be disconnected */
diff --git a/src/core/transport/transport_op_string.c b/src/core/transport/transport_op_string.c
index f3b6db29d6..98b51afc88 100644
--- a/src/core/transport/transport_op_string.c
+++ b/src/core/transport/transport_op_string.c
@@ -63,8 +63,8 @@ static void put_metadata_list(gpr_strvec *b, grpc_metadata_batch md) {
   }
   if (gpr_time_cmp(md.deadline, gpr_inf_future(md.deadline.clock_type)) != 0) {
     char *tmp;
-    gpr_asprintf(&tmp, " deadline=%d.%09d", md.deadline.tv_sec,
-                 md.deadline.tv_nsec);
+    gpr_asprintf(&tmp, " deadline=%lld.%09d", (long long)md.deadline.tv_sec,
+                 (int)md.deadline.tv_nsec);
     gpr_strvec_add(b, tmp);
   }
 }