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

30 files changed, 348 insertions, 145 deletions

diff --git a/include/grpc++/impl/codegen/call.h b/include/grpc++/impl/codegen/call.h
index d081b7d9c5..d457f03fa6 100644
--- a/include/grpc++/impl/codegen/call.h
+++ b/include/grpc++/impl/codegen/call.h
@@ -329,8 +329,11 @@ class CallOpGenericRecvMessage {
 
   template <class R>
   void RecvMessage(R* message) {
-    deserialize_.reset(
-        new CallOpGenericRecvMessageHelper::DeserializeFuncType<R>(message));
+    // Use an explicit base class pointer to avoid resolution error in the
+    // following unique_ptr::reset for some old implementations.
+    CallOpGenericRecvMessageHelper::DeserializeFunc* func =
+        new CallOpGenericRecvMessageHelper::DeserializeFuncType<R>(message);
+    deserialize_.reset(func);
   }
 
   bool got_message;
diff --git a/src/core/lib/channel/compress_filter.c b/src/core/lib/channel/compress_filter.c
index 5510c79b18..0e548c61b8 100644
--- a/src/core/lib/channel/compress_filter.c
+++ b/src/core/lib/channel/compress_filter.c
@@ -47,7 +47,7 @@
 #include "src/core/lib/support/string.h"
 #include "src/core/lib/transport/static_metadata.h"
 
-int grpc_compress_filter_trace = 0;
+int grpc_compression_trace = 0;
 
 typedef struct call_data {
   gpr_slice_buffer slices; /**< Buffers up input slices to be compressed */
@@ -171,7 +171,7 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
   did_compress =
       grpc_msg_compress(calld->compression_algorithm, &calld->slices, &tmp);
   if (did_compress) {
-    if (grpc_compress_filter_trace) {
+    if (grpc_compression_trace) {
       char *algo_name;
       const size_t before_size = calld->slices.length;
       const size_t after_size = tmp.length;
@@ -185,12 +185,14 @@ static void finish_send_message(grpc_exec_ctx *exec_ctx,
     gpr_slice_buffer_swap(&calld->slices, &tmp);
     calld->send_flags |= GRPC_WRITE_INTERNAL_COMPRESS;
   } else {
-    if (grpc_compress_filter_trace) {
+    if (grpc_compression_trace) {
       char *algo_name;
       GPR_ASSERT(grpc_compression_algorithm_name(calld->compression_algorithm,
                                                  &algo_name));
-      gpr_log(GPR_DEBUG, "Algorithm '%s' enabled but decided not to compress.",
-              algo_name);
+      gpr_log(
+          GPR_DEBUG,
+          "Algorithm '%s' enabled but decided not to compress. Input size: %d",
+          algo_name, calld->slices.length);
     }
   }
 
diff --git a/src/core/lib/channel/compress_filter.h b/src/core/lib/channel/compress_filter.h
index cf5879d82e..0ce5d08837 100644
--- a/src/core/lib/channel/compress_filter.h
+++ b/src/core/lib/channel/compress_filter.h
@@ -38,7 +38,7 @@
 
 #define GRPC_COMPRESS_REQUEST_ALGORITHM_KEY "grpc-internal-encoding-request"
 
-extern int grpc_compress_filter_trace;
+extern int grpc_compression_trace;
 
 /** Compression filter for outgoing data.
  *
diff --git a/src/core/lib/surface/byte_buffer_reader.c b/src/core/lib/surface/byte_buffer_reader.c
index 809fd5f1fa..c97079f638 100644
--- a/src/core/lib/surface/byte_buffer_reader.c
+++ b/src/core/lib/surface/byte_buffer_reader.c
@@ -62,12 +62,19 @@ void grpc_byte_buffer_reader_init(grpc_byte_buffer_reader *reader,
     case GRPC_BB_RAW:
       gpr_slice_buffer_init(&decompressed_slices_buffer);
       if (is_compressed(reader->buffer_in)) {
-        grpc_msg_decompress(reader->buffer_in->data.raw.compression,
-                            &reader->buffer_in->data.raw.slice_buffer,
-                            &decompressed_slices_buffer);
-        reader->buffer_out =
-            grpc_raw_byte_buffer_create(decompressed_slices_buffer.slices,
-                                        decompressed_slices_buffer.count);
+        if (grpc_msg_decompress(reader->buffer_in->data.raw.compression,
+                                &reader->buffer_in->data.raw.slice_buffer,
+                                &decompressed_slices_buffer) == 0) {
+          gpr_log(GPR_ERROR,
+                  "Unexpected error decompressing data for algorithm with enum "
+                  "value '%d'. Reading data as if it were uncompressed.",
+                  reader->buffer_in->data.raw.compression);
+          reader->buffer_out = reader->buffer_in;
+        } else { /* all fine */
+          reader->buffer_out =
+              grpc_raw_byte_buffer_create(decompressed_slices_buffer.slices,
+                                          decompressed_slices_buffer.count);
+        }
         gpr_slice_buffer_destroy(&decompressed_slices_buffer);
       } else { /* not compressed, use the input buffer as output */
         reader->buffer_out = reader->buffer_in;
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 99bb4798aa..b5469e1ff9 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -267,6 +267,8 @@ grpc_call *grpc_call_create(grpc_channel *channel, grpc_call *parent_call,
   call->channel = channel;
   call->cq = cq;
   call->parent = parent_call;
+  /* Always support no compression */
+  GPR_BITSET(&call->encodings_accepted_by_peer, GRPC_COMPRESS_NONE);
   call->is_client = server_transport_data == NULL;
   if (call->is_client) {
     GPR_ASSERT(add_initial_metadata_count < MAX_SEND_EXTRA_METADATA_COUNT);
@@ -414,6 +416,7 @@ static void set_status_code(grpc_call *call, status_source source,
 
 static void set_compression_algorithm(grpc_call *call,
                                       grpc_compression_algorithm algo) {
+  GPR_ASSERT(algo < GRPC_COMPRESS_ALGORITHMS_COUNT);
   call->compression_algorithm = algo;
 }
 
@@ -888,12 +891,16 @@ static uint32_t decode_status(grpc_mdelem *md) {
   return status;
 }
 
-static uint32_t decode_compression(grpc_mdelem *md) {
+static grpc_compression_algorithm decode_compression(grpc_mdelem *md) {
   grpc_compression_algorithm algorithm =
       grpc_compression_algorithm_from_mdstr(md->value);
   if (algorithm == GRPC_COMPRESS_ALGORITHMS_COUNT) {
     const char *md_c_str = grpc_mdstr_as_c_string(md->value);
-    gpr_log(GPR_ERROR, "Invalid compression algorithm: '%s'", md_c_str);
+    gpr_log(GPR_ERROR,
+            "Invalid incoming compression algorithm: '%s'. Interpreting "
+            "incoming data as uncompressed.",
+            md_c_str);
+    return GRPC_COMPRESS_NONE;
   }
   return algorithm;
 }
@@ -1136,6 +1143,7 @@ static void receiving_stream_ready(grpc_exec_ctx *exec_ctx, void *bctlp,
 static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
                                        batch_control *bctl) {
   grpc_call *call = bctl->call;
+  /* validate call->compression_algorithm */
   if (call->compression_algorithm != GRPC_COMPRESS_NONE) {
     const grpc_compression_algorithm algo = call->compression_algorithm;
     char *error_msg = NULL;
@@ -1161,6 +1169,23 @@ static void validate_filtered_metadata(grpc_exec_ctx *exec_ctx,
     }
     gpr_free(error_msg);
   }
+
+  /* make sure the received grpc-encoding is amongst the ones listed in
+   * grpc-accept-encoding */
+  GPR_ASSERT(call->encodings_accepted_by_peer != 0);
+  if (!GPR_BITGET(call->encodings_accepted_by_peer,
+                  call->compression_algorithm)) {
+    extern int grpc_compression_trace;
+    if (grpc_compression_trace) {
+      char *algo_name;
+      grpc_compression_algorithm_name(call->compression_algorithm, &algo_name);
+      gpr_log(GPR_ERROR,
+              "Compression algorithm (grpc-encoding = '%s') not present in "
+              "the bitset of accepted encodings (grpc-accept-encodings: "
+              "'0x%x')",
+              algo_name, call->encodings_accepted_by_peer);
+    }
+  }
 }
 
 static void receiving_initial_metadata_ready(grpc_exec_ctx *exec_ctx,
@@ -1568,7 +1593,8 @@ grpc_call_error grpc_call_start_batch(grpc_call *call, const grpc_op *ops,
   grpc_call_error err;
 
   GRPC_API_TRACE(
-      "grpc_call_start_batch(call=%p, ops=%p, nops=%lu, tag=%p, reserved=%p)",
+      "grpc_call_start_batch(call=%p, ops=%p, nops=%lu, tag=%p, "
+      "reserved=%p)",
       5, (call, ops, (unsigned long)nops, tag, reserved));
 
   if (reserved != NULL) {
diff --git a/src/core/lib/surface/init.c b/src/core/lib/surface/init.c
index 57c6897626..1c8b709015 100644
--- a/src/core/lib/surface/init.c
+++ b/src/core/lib/surface/init.c
@@ -164,7 +164,7 @@ void grpc_init(void) {
     grpc_register_tracer("channel_stack_builder",
                          &grpc_trace_channel_stack_builder);
     grpc_register_tracer("http1", &grpc_http1_trace);
-    grpc_register_tracer("compression", &grpc_compress_filter_trace);
+    grpc_register_tracer("compression", &grpc_compression_trace);
     grpc_security_pre_init();
     grpc_iomgr_init();
     grpc_executor_init();
diff --git a/src/php/ext/grpc/call.c b/src/php/ext/grpc/call.c
index a2c1c08169..884130e7d4 100644
--- a/src/php/ext/grpc/call.c
+++ b/src/php/ext/grpc/call.c
@@ -89,7 +89,7 @@ zend_object_value create_wrapped_grpc_call(zend_class_entry *class_type
 
 /* Wraps a grpc_call struct in a PHP object. Owned indicates whether the struct
    should be destroyed at the end of the object's lifecycle */
-zval *grpc_php_wrap_call(grpc_call *wrapped, bool owned) {
+zval *grpc_php_wrap_call(grpc_call *wrapped, bool owned TSRMLS_DC) {
   zval *call_object;
   MAKE_STD_ZVAL(call_object);
   object_init_ex(call_object, grpc_ce_call);
@@ -102,7 +102,7 @@ zval *grpc_php_wrap_call(grpc_call *wrapped, bool owned) {
 
 /* Creates and returns a PHP array object with the data in a
  * grpc_metadata_array. Returns NULL on failure */
-zval *grpc_parse_metadata_array(grpc_metadata_array *metadata_array) {
+zval *grpc_parse_metadata_array(grpc_metadata_array *metadata_array TSRMLS_DC) {
   int count = metadata_array->count;
   grpc_metadata *elements = metadata_array->metadata;
   int i;
@@ -127,7 +127,7 @@ zval *grpc_parse_metadata_array(grpc_metadata_array *metadata_array) {
     if (zend_hash_find(array_hash, str_key, key_len, (void **)data) ==
         SUCCESS) {
       if (Z_TYPE_P(*data) != IS_ARRAY) {
-        zend_throw_exception(zend_exception_get_default(),
+        zend_throw_exception(zend_exception_get_default(TSRMLS_C),
                              "Metadata hash somehow contains wrong types.",
                              1 TSRMLS_CC);
         efree(str_key);
@@ -454,7 +454,7 @@ PHP_METHOD(Call, startBatch) {
         add_property_bool(result, "send_status", true);
         break;
       case GRPC_OP_RECV_INITIAL_METADATA:
-        array = grpc_parse_metadata_array(&recv_metadata);
+        array = grpc_parse_metadata_array(&recv_metadata TSRMLS_CC);
         add_property_zval(result, "metadata", array);
         Z_DELREF_P(array);
         break;
@@ -470,7 +470,7 @@ PHP_METHOD(Call, startBatch) {
       case GRPC_OP_RECV_STATUS_ON_CLIENT:
         MAKE_STD_ZVAL(recv_status);
         object_init(recv_status);
-        array = grpc_parse_metadata_array(&recv_trailing_metadata);
+        array = grpc_parse_metadata_array(&recv_trailing_metadata TSRMLS_CC);
         add_property_zval(recv_status, "metadata", array);
         Z_DELREF_P(array);
         add_property_long(recv_status, "code", status);
diff --git a/src/php/ext/grpc/call.h b/src/php/ext/grpc/call.h
index 73efadae35..36c5f2d272 100644
--- a/src/php/ext/grpc/call.h
+++ b/src/php/ext/grpc/call.h
@@ -60,11 +60,11 @@ typedef struct wrapped_grpc_call {
 void grpc_init_call(TSRMLS_D);
 
 /* Creates a Call object that wraps the given grpc_call struct */
-zval *grpc_php_wrap_call(grpc_call *wrapped, bool owned);
+zval *grpc_php_wrap_call(grpc_call *wrapped, bool owned TSRMLS_DC);
 
 /* Creates and returns a PHP associative array of metadata from a C array of
  * call metadata */
-zval *grpc_parse_metadata_array(grpc_metadata_array *metadata_array);
+zval *grpc_parse_metadata_array(grpc_metadata_array *metadata_array TSRMLS_DC);
 
 /* Populates a grpc_metadata_array with the data in a PHP array object.
    Returns true on success and false on failure */
diff --git a/src/php/ext/grpc/call_credentials.c b/src/php/ext/grpc/call_credentials.c
index 285c4e7c85..ec0e6b9181 100644
--- a/src/php/ext/grpc/call_credentials.c
+++ b/src/php/ext/grpc/call_credentials.c
@@ -83,7 +83,7 @@ zend_object_value create_wrapped_grpc_call_credentials(
   return retval;
 }
 
-zval *grpc_php_wrap_call_credentials(grpc_call_credentials *wrapped) {
+zval *grpc_php_wrap_call_credentials(grpc_call_credentials *wrapped TSRMLS_DC) {
   zval *credentials_object;
   MAKE_STD_ZVAL(credentials_object);
   object_init_ex(credentials_object, grpc_ce_call_credentials);
@@ -122,7 +122,7 @@ PHP_METHOD(CallCredentials, createComposite) {
   grpc_call_credentials *creds =
       grpc_composite_call_credentials_create(cred1->wrapped, cred2->wrapped,
                                              NULL);
-  zval *creds_object = grpc_php_wrap_call_credentials(creds);
+  zval *creds_object = grpc_php_wrap_call_credentials(creds TSRMLS_CC);
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
@@ -141,7 +141,7 @@ PHP_METHOD(CallCredentials, createFromPlugin) {
   memset(fci_cache, 0, sizeof(zend_fcall_info_cache));
 
   /* "f" == 1 function */
-  if (zend_parse_parameters(ZEND_NUM_ARGS(), "f", fci,
+  if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "f", fci,
                             fci_cache,
                             fci->params,
                             fci->param_count) == FAILURE) {
@@ -167,7 +167,7 @@ PHP_METHOD(CallCredentials, createFromPlugin) {
 
   grpc_call_credentials *creds = grpc_metadata_credentials_create_from_plugin(
       plugin, NULL);
-  zval *creds_object = grpc_php_wrap_call_credentials(creds);
+  zval *creds_object = grpc_php_wrap_call_credentials(creds TSRMLS_CC);
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
@@ -175,6 +175,8 @@ PHP_METHOD(CallCredentials, createFromPlugin) {
 void plugin_get_metadata(void *ptr, grpc_auth_metadata_context context,
                          grpc_credentials_plugin_metadata_cb cb,
                          void *user_data) {
+  TSRMLS_FETCH();
+
   plugin_state *state = (plugin_state *)ptr;
 
   /* prepare to call the user callback function with info from the
@@ -192,7 +194,7 @@ void plugin_get_metadata(void *ptr, grpc_auth_metadata_context context,
   state->fci->retval_ptr_ptr = &retval;
 
   /* call the user callback function */
-  zend_call_function(state->fci, state->fci_cache);
+  zend_call_function(state->fci, state->fci_cache TSRMLS_CC);
 
   if (Z_TYPE_P(retval) != IS_ARRAY) {
     zend_throw_exception(spl_ce_InvalidArgumentException,
diff --git a/src/php/ext/grpc/channel.c b/src/php/ext/grpc/channel.c
index eba2c81424..9f0431908f 100644
--- a/src/php/ext/grpc/channel.c
+++ b/src/php/ext/grpc/channel.c
@@ -84,7 +84,7 @@ zend_object_value create_wrapped_grpc_channel(zend_class_entry *class_type
   return retval;
 }
 
-void php_grpc_read_args_array(zval *args_array, grpc_channel_args *args) {
+void php_grpc_read_args_array(zval *args_array, grpc_channel_args *args TSRMLS_DC) {
   HashTable *array_hash;
   HashPosition array_pointer;
   int args_index;
@@ -168,7 +168,7 @@ PHP_METHOD(Channel, __construct) {
       zend_hash_del(array_hash, "credentials", 12);
     }
   }
-  php_grpc_read_args_array(args_array, &args);
+  php_grpc_read_args_array(args_array, &args TSRMLS_CC);
   if (creds == NULL) {
     channel->wrapped = grpc_insecure_channel_create(target, &args, NULL);
   } else {
diff --git a/src/php/ext/grpc/channel.h b/src/php/ext/grpc/channel.h
index 78a16ed0c9..cc5823ee7f 100755
--- a/src/php/ext/grpc/channel.h
+++ b/src/php/ext/grpc/channel.h
@@ -59,6 +59,6 @@ typedef struct wrapped_grpc_channel {
 void grpc_init_channel(TSRMLS_D);
 
 /* Iterates through a PHP array and populates args with the contents */
-void php_grpc_read_args_array(zval *args_array, grpc_channel_args *args);
+void php_grpc_read_args_array(zval *args_array, grpc_channel_args *args TSRMLS_DC);
 
 #endif /* NET_GRPC_PHP_GRPC_CHANNEL_H_ */
diff --git a/src/php/ext/grpc/channel_credentials.c b/src/php/ext/grpc/channel_credentials.c
index ae9a9897fc..5c537378a6 100644
--- a/src/php/ext/grpc/channel_credentials.c
+++ b/src/php/ext/grpc/channel_credentials.c
@@ -82,7 +82,7 @@ zend_object_value create_wrapped_grpc_channel_credentials(
   return retval;
 }
 
-zval *grpc_php_wrap_channel_credentials(grpc_channel_credentials *wrapped) {
+zval *grpc_php_wrap_channel_credentials(grpc_channel_credentials *wrapped TSRMLS_DC) {
   zval *credentials_object;
   MAKE_STD_ZVAL(credentials_object);
   object_init_ex(credentials_object, grpc_ce_channel_credentials);
@@ -99,7 +99,7 @@ zval *grpc_php_wrap_channel_credentials(grpc_channel_credentials *wrapped) {
  */
 PHP_METHOD(ChannelCredentials, createDefault) {
   grpc_channel_credentials *creds = grpc_google_default_credentials_create();
-  zval *creds_object = grpc_php_wrap_channel_credentials(creds);
+  zval *creds_object = grpc_php_wrap_channel_credentials(creds TSRMLS_CC);
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
@@ -134,7 +134,7 @@ PHP_METHOD(ChannelCredentials, createSsl) {
   grpc_channel_credentials *creds = grpc_ssl_credentials_create(
       pem_root_certs,
       pem_key_cert_pair.private_key == NULL ? NULL : &pem_key_cert_pair, NULL);
-  zval *creds_object = grpc_php_wrap_channel_credentials(creds);
+  zval *creds_object = grpc_php_wrap_channel_credentials(creds TSRMLS_CC);
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
@@ -165,7 +165,7 @@ PHP_METHOD(ChannelCredentials, createComposite) {
   grpc_channel_credentials *creds =
       grpc_composite_channel_credentials_create(cred1->wrapped, cred2->wrapped,
                                                 NULL);
-  zval *creds_object = grpc_php_wrap_channel_credentials(creds);
+  zval *creds_object = grpc_php_wrap_channel_credentials(creds TSRMLS_CC);
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
diff --git a/src/php/ext/grpc/server.c b/src/php/ext/grpc/server.c
index ca129e76ca..6df2e4f978 100644
--- a/src/php/ext/grpc/server.c
+++ b/src/php/ext/grpc/server.c
@@ -111,7 +111,7 @@ PHP_METHOD(Server, __construct) {
   if (args_array == NULL) {
     server->wrapped = grpc_server_create(NULL, NULL);
   } else {
-    php_grpc_read_args_array(args_array, &args);
+    php_grpc_read_args_array(args_array, &args TSRMLS_CC);
     server->wrapped = grpc_server_create(&args, NULL);
     efree(args.args);
   }
@@ -154,12 +154,12 @@ PHP_METHOD(Server, requestCall) {
                          1 TSRMLS_CC);
     goto cleanup;
   }
-  add_property_zval(result, "call", grpc_php_wrap_call(call, true));
+  add_property_zval(result, "call", grpc_php_wrap_call(call, true TSRMLS_CC));
   add_property_string(result, "method", details.method, true);
   add_property_string(result, "host", details.host, true);
   add_property_zval(result, "absolute_deadline",
-                    grpc_php_wrap_timeval(details.deadline));
-  add_property_zval(result, "metadata", grpc_parse_metadata_array(&metadata));
+                    grpc_php_wrap_timeval(details.deadline TSRMLS_CC));
+  add_property_zval(result, "metadata", grpc_parse_metadata_array(&metadata TSRMLS_CC));
 cleanup:
   grpc_call_details_destroy(&details);
   grpc_metadata_array_destroy(&metadata);
diff --git a/src/php/ext/grpc/server_credentials.c b/src/php/ext/grpc/server_credentials.c
index f3951b31fe..505da10a28 100644
--- a/src/php/ext/grpc/server_credentials.c
+++ b/src/php/ext/grpc/server_credentials.c
@@ -81,7 +81,7 @@ zend_object_value create_wrapped_grpc_server_credentials(
   return retval;
 }
 
-zval *grpc_php_wrap_server_credentials(grpc_server_credentials *wrapped) {
+zval *grpc_php_wrap_server_credentials(grpc_server_credentials *wrapped TSRMLS_DC) {
   zval *server_credentials_object;
   MAKE_STD_ZVAL(server_credentials_object);
   object_init_ex(server_credentials_object, grpc_ce_server_credentials);
@@ -120,7 +120,7 @@ PHP_METHOD(ServerCredentials, createSsl) {
   grpc_server_credentials *creds = grpc_ssl_server_credentials_create_ex(
       pem_root_certs, &pem_key_cert_pair, 1,
       GRPC_SSL_DONT_REQUEST_CLIENT_CERTIFICATE, NULL);
-  zval *creds_object = grpc_php_wrap_server_credentials(creds);
+  zval *creds_object = grpc_php_wrap_server_credentials(creds TSRMLS_CC);
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
diff --git a/src/php/ext/grpc/timeval.c b/src/php/ext/grpc/timeval.c
index 4fd069e19a..5e242162a8 100644
--- a/src/php/ext/grpc/timeval.c
+++ b/src/php/ext/grpc/timeval.c
@@ -72,7 +72,7 @@ zend_object_value create_wrapped_grpc_timeval(zend_class_entry *class_type
   return retval;
 }
 
-zval *grpc_php_wrap_timeval(gpr_timespec wrapped) {
+zval *grpc_php_wrap_timeval(gpr_timespec wrapped TSRMLS_DC) {
   zval *timeval_object;
   MAKE_STD_ZVAL(timeval_object);
   object_init_ex(timeval_object, grpc_ce_timeval);
@@ -122,7 +122,7 @@ PHP_METHOD(Timeval, add) {
   wrapped_grpc_timeval *other =
       (wrapped_grpc_timeval *)zend_object_store_get_object(other_obj TSRMLS_CC);
   zval *sum =
-      grpc_php_wrap_timeval(gpr_time_add(self->wrapped, other->wrapped));
+      grpc_php_wrap_timeval(gpr_time_add(self->wrapped, other->wrapped) TSRMLS_CC);
   RETURN_DESTROY_ZVAL(sum);
 }
 
@@ -146,7 +146,7 @@ PHP_METHOD(Timeval, subtract) {
   wrapped_grpc_timeval *other =
       (wrapped_grpc_timeval *)zend_object_store_get_object(other_obj TSRMLS_CC);
   zval *diff =
-      grpc_php_wrap_timeval(gpr_time_sub(self->wrapped, other->wrapped));
+      grpc_php_wrap_timeval(gpr_time_sub(self->wrapped, other->wrapped) TSRMLS_CC);
   RETURN_DESTROY_ZVAL(diff);
 }
 
@@ -208,7 +208,7 @@ PHP_METHOD(Timeval, similar) {
  * @return Timeval The current time
  */
 PHP_METHOD(Timeval, now) {
-  zval *now = grpc_php_wrap_timeval(gpr_now(GPR_CLOCK_REALTIME));
+  zval *now = grpc_php_wrap_timeval(gpr_now(GPR_CLOCK_REALTIME) TSRMLS_CC);
   RETURN_DESTROY_ZVAL(now);
 }
 
@@ -218,7 +218,7 @@ PHP_METHOD(Timeval, now) {
  */
 PHP_METHOD(Timeval, zero) {
   zval *grpc_php_timeval_zero =
-      grpc_php_wrap_timeval(gpr_time_0(GPR_CLOCK_REALTIME));
+      grpc_php_wrap_timeval(gpr_time_0(GPR_CLOCK_REALTIME) TSRMLS_CC);
   RETURN_ZVAL(grpc_php_timeval_zero,
               false, /* Copy original before returning? */
               true /* Destroy original before returning */);
@@ -230,7 +230,7 @@ PHP_METHOD(Timeval, zero) {
  */
 PHP_METHOD(Timeval, infFuture) {
   zval *grpc_php_timeval_inf_future =
-      grpc_php_wrap_timeval(gpr_inf_future(GPR_CLOCK_REALTIME));
+      grpc_php_wrap_timeval(gpr_inf_future(GPR_CLOCK_REALTIME) TSRMLS_CC);
   RETURN_DESTROY_ZVAL(grpc_php_timeval_inf_future);
 }
 
@@ -240,7 +240,7 @@ PHP_METHOD(Timeval, infFuture) {
  */
 PHP_METHOD(Timeval, infPast) {
   zval *grpc_php_timeval_inf_past =
-      grpc_php_wrap_timeval(gpr_inf_past(GPR_CLOCK_REALTIME));
+      grpc_php_wrap_timeval(gpr_inf_past(GPR_CLOCK_REALTIME) TSRMLS_CC);
   RETURN_DESTROY_ZVAL(grpc_php_timeval_inf_past);
 }
 
diff --git a/src/php/ext/grpc/timeval.h b/src/php/ext/grpc/timeval.h
index 07cef037cb..7456eb6d58 100755
--- a/src/php/ext/grpc/timeval.h
+++ b/src/php/ext/grpc/timeval.h
@@ -63,6 +63,6 @@ void grpc_init_timeval(TSRMLS_D);
 void grpc_shutdown_timeval(TSRMLS_D);
 
 /* Creates a Timeval object that wraps the given timeval struct */
-zval *grpc_php_wrap_timeval(gpr_timespec wrapped);
+zval *grpc_php_wrap_timeval(gpr_timespec wrapped TSRMLS_DC);
 
 #endif /* NET_GRPC_PHP_GRPC_TIMEVAL_H_ */
diff --git a/src/python/grpcio/grpc/_adapter/_low.py b/src/python/grpcio/grpc/_adapter/_low.py
index b13d8dd9dd..00788bd4cf 100644
--- a/src/python/grpcio/grpc/_adapter/_low.py
+++ b/src/python/grpcio/grpc/_adapter/_low.py
@@ -195,26 +195,30 @@ class Call(_types.Call):
         translated_op = cygrpc.operation_send_initial_metadata(
             cygrpc.Metadata(
                 cygrpc.Metadatum(key, value)
-                for key, value in op.initial_metadata))
+                for key, value in op.initial_metadata),
+            op.flags)
       elif op.type == _types.OpType.SEND_MESSAGE:
-        translated_op = cygrpc.operation_send_message(op.message)
+        translated_op = cygrpc.operation_send_message(op.message, op.flags)
       elif op.type == _types.OpType.SEND_CLOSE_FROM_CLIENT:
-        translated_op = cygrpc.operation_send_close_from_client()
+        translated_op = cygrpc.operation_send_close_from_client(op.flags)
       elif op.type == _types.OpType.SEND_STATUS_FROM_SERVER:
         translated_op = cygrpc.operation_send_status_from_server(
             cygrpc.Metadata(
                 cygrpc.Metadatum(key, value)
                 for key, value in op.trailing_metadata),
             op.status.code,
-            op.status.details)
+            op.status.details,
+            op.flags)
       elif op.type == _types.OpType.RECV_INITIAL_METADATA:
-        translated_op = cygrpc.operation_receive_initial_metadata()
+        translated_op = cygrpc.operation_receive_initial_metadata(
+            op.flags)
       elif op.type == _types.OpType.RECV_MESSAGE:
-        translated_op = cygrpc.operation_receive_message()
+        translated_op = cygrpc.operation_receive_message(op.flags)
       elif op.type == _types.OpType.RECV_STATUS_ON_CLIENT:
-        translated_op = cygrpc.operation_receive_status_on_client()
+        translated_op = cygrpc.operation_receive_status_on_client(
+            op.flags)
       elif op.type == _types.OpType.RECV_CLOSE_ON_SERVER:
-        translated_op = cygrpc.operation_receive_close_on_server()
+        translated_op = cygrpc.operation_receive_close_on_server(op.flags)
       else:
         raise ValueError('unexpected operation type {}'.format(op.type))
       translated_ops.append(translated_op)
diff --git a/src/python/grpcio/grpc/_adapter/_types.py b/src/python/grpcio/grpc/_adapter/_types.py
index 8ca7ff4b60..f8405949d4 100644
--- a/src/python/grpcio/grpc/_adapter/_types.py
+++ b/src/python/grpcio/grpc/_adapter/_types.py
@@ -152,7 +152,7 @@ class OpArgs(collections.namedtuple(
         'trailing_metadata',
         'message',
         'status',
-        'write_flags',
+        'flags',
     ])):
   """Arguments passed into a GRPC operation.
 
@@ -165,7 +165,7 @@ class OpArgs(collections.namedtuple(
     message (bytes): Only valid if type == OpType.SEND_MESSAGE, else is None.
     status (Status): Only valid if type == OpType.SEND_STATUS_FROM_SERVER, else
       is None.
-    write_flags (int): a bit OR'ing of 0 or more OpWriteFlags values.
+    flags (int): a bitwise OR'ing of 0 or more OpWriteFlags values.
   """
 
   @staticmethod
diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/grpc.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/grpc.pxi
index 3d158a7707..66e6e6b549 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/grpc.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/grpc.pxi
@@ -140,6 +140,9 @@ cdef extern from "grpc/_cython/loader.h":
   const char *GRPC_ARG_PRIMARY_USER_AGENT_STRING
   const char *GRPC_ARG_SECONDARY_USER_AGENT_STRING
   const char *GRPC_SSL_TARGET_NAME_OVERRIDE_ARG
+  const char *GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM
+  const char *GRPC_COMPRESSION_CHANNEL_DEFAULT_LEVEL
+  const char *GRPC_COMPRESSION_CHANNEL_ENABLED_ALGORITHMS_BITSET
 
   const int GRPC_WRITE_BUFFER_HINT
   const int GRPC_WRITE_NO_COMPRESS
@@ -425,3 +428,38 @@ cdef extern from "grpc/_cython/loader.h":
 
   grpc_call_credentials *grpc_metadata_credentials_create_from_plugin(
       grpc_metadata_credentials_plugin plugin, void *reserved) nogil
+
+  ctypedef enum grpc_compression_algorithm:
+    GRPC_COMPRESS_NONE
+    GRPC_COMPRESS_DEFLATE
+    GRPC_COMPRESS_GZIP
+    GRPC_COMPRESS_ALGORITHMS_COUNT
+
+  ctypedef enum grpc_compression_level:
+    GRPC_COMPRESS_LEVEL_NONE
+    GRPC_COMPRESS_LEVEL_LOW
+    GRPC_COMPRESS_LEVEL_MED
+    GRPC_COMPRESS_LEVEL_HIGH
+    GRPC_COMPRESS_LEVEL_COUNT
+
+  ctypedef struct grpc_compression_options:
+    uint32_t enabled_algorithms_bitset
+    grpc_compression_algorithm default_compression_algorithm
+
+  int grpc_compression_algorithm_parse(
+      const char *name, size_t name_length,
+      grpc_compression_algorithm *algorithm) nogil
+  int grpc_compression_algorithm_name(grpc_compression_algorithm algorithm,
+                                      char **name) nogil
+  grpc_compression_algorithm grpc_compression_algorithm_for_level(
+      grpc_compression_level level, uint32_t accepted_encodings) nogil
+  void grpc_compression_options_init(grpc_compression_options *opts) nogil
+  void grpc_compression_options_enable_algorithm(
+      grpc_compression_options *opts,
+      grpc_compression_algorithm algorithm) nogil
+  void grpc_compression_options_disable_algorithm(
+      grpc_compression_options *opts,
+      grpc_compression_algorithm algorithm) nogil
+  int grpc_compression_options_is_algorithm_enabled(
+      const grpc_compression_options *opts,
+      grpc_compression_algorithm algorithm) nogil
diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/records.pxd.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/records.pxd.pxi
index 30397818a1..0474697af8 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/records.pxd.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/records.pxd.pxi
@@ -124,3 +124,7 @@ cdef class Operations:
   cdef size_t c_nops
   cdef list operations
 
+
+cdef class CompressionOptions:
+
+  cdef grpc_compression_options c_options
diff --git a/src/python/grpcio/grpc/_cython/_cygrpc/records.pyx.pxi b/src/python/grpcio/grpc/_cython/_cygrpc/records.pyx.pxi
index c2202bdab2..c7539f0d49 100644
--- a/src/python/grpcio/grpc/_cython/_cygrpc/records.pyx.pxi
+++ b/src/python/grpcio/grpc/_cython/_cygrpc/records.pyx.pxi
@@ -103,6 +103,19 @@ class OperationType:
   receive_close_on_server = GRPC_OP_RECV_CLOSE_ON_SERVER
 
 
+class CompressionAlgorithm:
+  none = GRPC_COMPRESS_NONE
+  deflate = GRPC_COMPRESS_DEFLATE
+  gzip = GRPC_COMPRESS_GZIP
+
+
+class CompressionLevel:
+  none = GRPC_COMPRESS_LEVEL_NONE
+  low = GRPC_COMPRESS_LEVEL_LOW
+  medium = GRPC_COMPRESS_LEVEL_MED
+  high = GRPC_COMPRESS_LEVEL_HIGH
+
+
 cdef class Timespec:
 
   def __cinit__(self, time):
@@ -473,6 +486,10 @@ cdef class Operation:
     return self.c_op.type
 
   @property
+  def flags(self):
+    return self.c_op.flags
+
+  @property
   def has_status(self):
     return self.c_op.type == GRPC_OP_RECV_STATUS_ON_CLIENT
 
@@ -553,9 +570,10 @@ cdef class Operation:
       with nogil:
         gpr_free(self._received_status_details)
 
-def operation_send_initial_metadata(Metadata metadata):
+def operation_send_initial_metadata(Metadata metadata, int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_SEND_INITIAL_METADATA
+  op.c_op.flags = flags
   op.c_op.data.send_initial_metadata.count = metadata.c_metadata_array.count
   op.c_op.data.send_initial_metadata.metadata = (
       metadata.c_metadata_array.metadata)
@@ -563,23 +581,25 @@ def operation_send_initial_metadata(Metadata metadata):
   op.is_valid = True
   return op
 
-def operation_send_message(data):
+def operation_send_message(data, int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_SEND_MESSAGE
+  op.c_op.flags = flags
   byte_buffer = ByteBuffer(data)
   op.c_op.data.send_message = byte_buffer.c_byte_buffer
   op.references.append(byte_buffer)
   op.is_valid = True
   return op
 
-def operation_send_close_from_client():
+def operation_send_close_from_client(int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_SEND_CLOSE_FROM_CLIENT
+  op.c_op.flags = flags
   op.is_valid = True
   return op
 
 def operation_send_status_from_server(
-    Metadata metadata, grpc_status_code code, details):
+    Metadata metadata, grpc_status_code code, details, int flags):
   if isinstance(details, bytes):
     pass
   elif isinstance(details, basestring):
@@ -588,6 +608,7 @@ def operation_send_status_from_server(
     raise TypeError("expected a str or bytes object for details")
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_SEND_STATUS_FROM_SERVER
+  op.c_op.flags = flags
   op.c_op.data.send_status_from_server.trailing_metadata_count = (
       metadata.c_metadata_array.count)
   op.c_op.data.send_status_from_server.trailing_metadata = (
@@ -599,18 +620,20 @@ def operation_send_status_from_server(
   op.is_valid = True
   return op
 
-def operation_receive_initial_metadata():
+def operation_receive_initial_metadata(int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_RECV_INITIAL_METADATA
+  op.c_op.flags = flags
   op._received_metadata = Metadata([])
   op.c_op.data.receive_initial_metadata = (
       &op._received_metadata.c_metadata_array)
   op.is_valid = True
   return op
 
-def operation_receive_message():
+def operation_receive_message(int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_RECV_MESSAGE
+  op.c_op.flags = flags
   op._received_message = ByteBuffer(None)
   # n.b. the c_op.data.receive_message field needs to be deleted by us,
   # anyway, so we just let that be handled by the ByteBuffer() we allocated
@@ -619,9 +642,10 @@ def operation_receive_message():
   op.is_valid = True
   return op
 
-def operation_receive_status_on_client():
+def operation_receive_status_on_client(int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_RECV_STATUS_ON_CLIENT
+  op.c_op.flags = flags
   op._received_metadata = Metadata([])
   op.c_op.data.receive_status_on_client.trailing_metadata = (
       &op._received_metadata.c_metadata_array)
@@ -634,9 +658,10 @@ def operation_receive_status_on_client():
   op.is_valid = True
   return op
 
-def operation_receive_close_on_server():
+def operation_receive_close_on_server(int flags):
   cdef Operation op = Operation()
   op.c_op.type = GRPC_OP_RECV_CLOSE_ON_SERVER
+  op.c_op.flags = flags
   op.c_op.data.receive_close_on_server.cancelled = &op._received_cancelled
   op.is_valid = True
   return op
@@ -692,3 +717,36 @@ cdef class Operations:
   def __iter__(self):
     return _OperationsIterator(self)
 
+
+cdef class CompressionOptions:
+
+  def __cinit__(self):
+    with nogil:
+      grpc_compression_options_init(&self.c_options)
+
+  def enable_algorithm(self, grpc_compression_algorithm algorithm):
+    with nogil:
+      grpc_compression_options_enable_algorithm(&self.c_options, algorithm)
+
+  def disable_algorithm(self, grpc_compression_algorithm algorithm):
+    with nogil:
+      grpc_compression_options_disable_algorithm(&self.c_options, algorithm)
+
+  def is_algorithm_enabled(self, grpc_compression_algorithm algorithm):
+    cdef int result
+    with nogil:
+      result = grpc_compression_options_is_algorithm_enabled(
+          &self.c_options, algorithm)
+    return result
+
+  def to_channel_arg(self):
+    return ChannelArg(GRPC_COMPRESSION_CHANNEL_ENABLED_ALGORITHMS_BITSET,
+                      self.c_options.enabled_algorithms_bitset)
+
+
+def compression_algorithm_name(grpc_compression_algorithm algorithm):
+  cdef char* name
+  with nogil:
+    grpc_compression_algorithm_name(algorithm, &name)
+  # Let Cython do the right thing with string casting
+  return name
diff --git a/src/python/grpcio/grpc/_cython/imports.generated.h b/src/python/grpcio/grpc/_cython/imports.generated.h
index 54c8aaad13..6de295414a 100644
--- a/src/python/grpcio/grpc/_cython/imports.generated.h
+++ b/src/python/grpcio/grpc/_cython/imports.generated.h
@@ -870,14 +870,15 @@ void pygrpc_load_imports(HMODULE library);
 
 #else /* !GPR_WIN32 */
 
-#include <grpc/support/alloc.h>
-#include <grpc/support/slice.h>
-#include <grpc/support/time.h>
-#include <grpc/status.h>
 #include <grpc/byte_buffer.h>
 #include <grpc/byte_buffer_reader.h>
+#include <grpc/compression.h>
 #include <grpc/grpc.h>
 #include <grpc/grpc_security.h>
+#include <grpc/support/alloc.h>
+#include <grpc/support/slice.h>
+#include <grpc/support/time.h>
+#include <grpc/status.h>
 
 #endif /* !GPR_WIN32 */
 
diff --git a/src/python/grpcio/tests/unit/_cython/cygrpc_test.py b/src/python/grpcio/tests/unit/_cython/cygrpc_test.py
index 876da88de9..0a511101f0 100644
--- a/src/python/grpcio/tests/unit/_cython/cygrpc_test.py
+++ b/src/python/grpcio/tests/unit/_cython/cygrpc_test.py
@@ -40,6 +40,7 @@ from tests.unit import resources
 _SSL_HOST_OVERRIDE = 'foo.test.google.fr'
 _CALL_CREDENTIALS_METADATA_KEY = 'call-creds-key'
 _CALL_CREDENTIALS_METADATA_VALUE = 'call-creds-value'
+_EMPTY_FLAGS = 0
 
 def _metadata_plugin_callback(context, callback):
   callback(cygrpc.Metadata(
@@ -76,7 +77,7 @@ class TypeSmokeTest(unittest.TestCase):
 
   def testOperationsIteration(self):
     operations = cygrpc.Operations([
-        cygrpc.operation_send_message('asdf')])
+        cygrpc.operation_send_message('asdf', _EMPTY_FLAGS)])
     iterator = iter(operations)
     operation = next(iterator)
     self.assertIsInstance(operation, cygrpc.Operation)
@@ -85,6 +86,11 @@ class TypeSmokeTest(unittest.TestCase):
     with self.assertRaises(StopIteration):
       next(iterator)
 
+  def testOperationFlags(self):
+    operation = cygrpc.operation_send_message('asdf',
+                                              cygrpc.WriteFlag.no_compress)
+    self.assertEqual(cygrpc.WriteFlag.no_compress, operation.flags)
+
   def testTimespec(self):
     now = time.time()
     timespec = cygrpc.Timespec(now)
@@ -188,12 +194,13 @@ class InsecureServerInsecureClient(unittest.TestCase):
                          CLIENT_METADATA_ASCII_VALUE),
         cygrpc.Metadatum(CLIENT_METADATA_BIN_KEY, CLIENT_METADATA_BIN_VALUE)])
     client_start_batch_result = client_call.start_batch(cygrpc.Operations([
-        cygrpc.operation_send_initial_metadata(client_initial_metadata),
-        cygrpc.operation_send_message(REQUEST),
-        cygrpc.operation_send_close_from_client(),
-        cygrpc.operation_receive_initial_metadata(),
-        cygrpc.operation_receive_message(),
-        cygrpc.operation_receive_status_on_client()
+        cygrpc.operation_send_initial_metadata(client_initial_metadata,
+                                               _EMPTY_FLAGS),
+        cygrpc.operation_send_message(REQUEST, _EMPTY_FLAGS),
+        cygrpc.operation_send_close_from_client(_EMPTY_FLAGS),
+        cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),
+        cygrpc.operation_receive_message(_EMPTY_FLAGS),
+        cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS)
     ]), client_call_tag)
     self.assertEqual(cygrpc.CallError.ok, client_start_batch_result)
     client_event_future = test_utilities.CompletionQueuePollFuture(
@@ -223,12 +230,14 @@ class InsecureServerInsecureClient(unittest.TestCase):
         cygrpc.Metadatum(SERVER_TRAILING_METADATA_KEY,
                          SERVER_TRAILING_METADATA_VALUE)])
     server_start_batch_result = server_call.start_batch([
-        cygrpc.operation_send_initial_metadata(server_initial_metadata),
-        cygrpc.operation_receive_message(),
-        cygrpc.operation_send_message(RESPONSE),
-        cygrpc.operation_receive_close_on_server(),
+        cygrpc.operation_send_initial_metadata(server_initial_metadata,
+                                               _EMPTY_FLAGS),
+        cygrpc.operation_receive_message(_EMPTY_FLAGS),
+        cygrpc.operation_send_message(RESPONSE, _EMPTY_FLAGS),
+        cygrpc.operation_receive_close_on_server(_EMPTY_FLAGS),
         cygrpc.operation_send_status_from_server(
-            server_trailing_metadata, SERVER_STATUS_CODE, SERVER_STATUS_DETAILS)
+            server_trailing_metadata, SERVER_STATUS_CODE,
+            SERVER_STATUS_DETAILS, _EMPTY_FLAGS)
     ], server_call_tag)
     self.assertEqual(cygrpc.CallError.ok, server_start_batch_result)
 
@@ -349,12 +358,13 @@ class SecureServerSecureClient(unittest.TestCase):
                          CLIENT_METADATA_ASCII_VALUE),
         cygrpc.Metadatum(CLIENT_METADATA_BIN_KEY, CLIENT_METADATA_BIN_VALUE)])
     client_start_batch_result = client_call.start_batch(cygrpc.Operations([
-        cygrpc.operation_send_initial_metadata(client_initial_metadata),
-        cygrpc.operation_send_message(REQUEST),
-        cygrpc.operation_send_close_from_client(),
-        cygrpc.operation_receive_initial_metadata(),
-        cygrpc.operation_receive_message(),
-        cygrpc.operation_receive_status_on_client()
+        cygrpc.operation_send_initial_metadata(client_initial_metadata,
+                                               _EMPTY_FLAGS),
+        cygrpc.operation_send_message(REQUEST, _EMPTY_FLAGS),
+        cygrpc.operation_send_close_from_client(_EMPTY_FLAGS),
+        cygrpc.operation_receive_initial_metadata(_EMPTY_FLAGS),
+        cygrpc.operation_receive_message(_EMPTY_FLAGS),
+        cygrpc.operation_receive_status_on_client(_EMPTY_FLAGS)
     ]), client_call_tag)
     self.assertEqual(cygrpc.CallError.ok, client_start_batch_result)
     client_event_future = test_utilities.CompletionQueuePollFuture(
@@ -387,12 +397,14 @@ class SecureServerSecureClient(unittest.TestCase):
         cygrpc.Metadatum(SERVER_TRAILING_METADATA_KEY,
                          SERVER_TRAILING_METADATA_VALUE)])
     server_start_batch_result = server_call.start_batch([
-        cygrpc.operation_send_initial_metadata(server_initial_metadata),
-        cygrpc.operation_receive_message(),
-        cygrpc.operation_send_message(RESPONSE),
-        cygrpc.operation_receive_close_on_server(),
+        cygrpc.operation_send_initial_metadata(server_initial_metadata,
+                                               _EMPTY_FLAGS),
+        cygrpc.operation_receive_message(_EMPTY_FLAGS),
+        cygrpc.operation_send_message(RESPONSE, _EMPTY_FLAGS),
+        cygrpc.operation_receive_close_on_server(_EMPTY_FLAGS),
         cygrpc.operation_send_status_from_server(
-            server_trailing_metadata, SERVER_STATUS_CODE, SERVER_STATUS_DETAILS)
+            server_trailing_metadata, SERVER_STATUS_CODE,
+            SERVER_STATUS_DETAILS, _EMPTY_FLAGS)
     ], server_call_tag)
     self.assertEqual(cygrpc.CallError.ok, server_start_batch_result)
 
diff --git a/templates/src/python/grpcio/grpc/_cython/imports.generated.h.template b/templates/src/python/grpcio/grpc/_cython/imports.generated.h.template
index 8e7c183180..26e717e58d 100644
--- a/templates/src/python/grpcio/grpc/_cython/imports.generated.h.template
+++ b/templates/src/python/grpcio/grpc/_cython/imports.generated.h.template
@@ -64,14 +64,15 @@
 
   #else /* !GPR_WIN32 */
 
-  #include <grpc/support/alloc.h>
-  #include <grpc/support/slice.h>
-  #include <grpc/support/time.h>
-  #include <grpc/status.h>
   #include <grpc/byte_buffer.h>
   #include <grpc/byte_buffer_reader.h>
+  #include <grpc/compression.h>
   #include <grpc/grpc.h>
   #include <grpc/grpc_security.h>
+  #include <grpc/support/alloc.h>
+  #include <grpc/support/slice.h>
+  #include <grpc/support/time.h>
+  #include <grpc/status.h>
 
   #endif /* !GPR_WIN32 */
 
diff --git a/test/core/util/port_posix.c b/test/core/util/port_posix.c
index f13960156f..265e0acee1 100644
--- a/test/core/util/port_posix.c
+++ b/test/core/util/port_posix.c
@@ -89,6 +89,7 @@ static int free_chosen_port(int port) {
       grpc_free_port_using_server(env, port);
     }
   }
+  gpr_free(env);
   return found;
 }
 
diff --git a/test/cpp/interop/interop_client.cc b/test/cpp/interop/interop_client.cc
index cba52b111f..189e4a8aab 100644
--- a/test/cpp/interop/interop_client.cc
+++ b/test/cpp/interop/interop_client.cc
@@ -60,7 +60,7 @@ static const char* kRandomFile = "test/cpp/interop/rnd.dat";
 namespace {
 // The same value is defined by the Java client.
 const std::vector<int> request_stream_sizes = {27182, 8, 1828, 45904};
-const std::vector<int> response_stream_sizes = {31415, 9, 2653, 58979};
+const std::vector<int> response_stream_sizes = {31415, 59, 2653, 58979};
 const int kNumResponseMessages = 2000;
 const int kResponseMessageSize = 1030;
 const int kReceiveDelayMilliSeconds = 20;
diff --git a/tools/distrib/check_include_guards.py b/tools/distrib/check_include_guards.py
index 9c23a70e00..ef770b30b4 100755
--- a/tools/distrib/check_include_guards.py
+++ b/tools/distrib/check_include_guards.py
@@ -98,6 +98,7 @@ class GuardValidator(object):
     match = self.ifndef_re.search(fcontents)
     if not match:
       print 'something drastically wrong with: %s' % fpath
+      return False # failed
     if match.lastindex is None:
       # No ifndef. Request manual addition with hints
       self.fail(fpath, match.re, match.string, '', '', False)
diff --git a/tools/run_tests/performance/scenario_config.py b/tools/run_tests/performance/scenario_config.py
index 4fe66dff41..77b158f27e 100644
--- a/tools/run_tests/performance/scenario_config.py
+++ b/tools/run_tests/performance/scenario_config.py
@@ -69,6 +69,10 @@ DEEP=100
 # wide is the number of client channels in multi-channel tests (1 otherwise)
 WIDE=64
 
+# For most synchronous clients, DEEP*WIDE threads will be created.
+SYNC_DEEP=10
+SYNC_WIDE=8
+
 
 def _get_secargs(is_secure):
   if is_secure:
@@ -81,6 +85,7 @@ def remove_nonproto_fields(scenario):
   """Remove special-purpose that contains some extra info about the scenario
   but don't belong to the ScenarioConfig protobuf message"""
   scenario.pop('CATEGORIES', None)
+  scenario.pop('CLIENT_LANGUAGE', None)
   scenario.pop('SERVER_LANGUAGE', None)
   return scenario
 
@@ -89,7 +94,8 @@ def _ping_pong_scenario(name, rpc_type,
                         client_type, server_type,
                         secure=True,
                         use_generic_payload=False,
-                        use_unconstrained_client=False,
+                        unconstrained_client=None,
+                        client_language=None,
                         server_language=None,
                         server_core_limit=0,
                         async_server_threads=0,
@@ -130,18 +136,28 @@ def _ping_pong_scenario(name, rpc_type,
     # For proto payload, only the client should get the config.
     scenario['client_config']['payload_config'] = EMPTY_PROTO_PAYLOAD
 
-  if use_unconstrained_client:
+  if unconstrained_client:
+    if unconstrained_client == 'async':
+      deep = DEEP
+      wide = WIDE
+    elif unconstrained_client == 'sync':
+      deep = SYNC_DEEP
+      wide = SYNC_WIDE
+    else:
+      raise Exception('Illegal value of unconstrained_client option.')
+
     scenario['num_clients'] = 0  # use as many client as available.
-    # TODO(jtattermusch): for SYNC_CLIENT, this will create 100*64 threads
-    # and that's probably too much (at least for wrapped languages).
-    scenario['client_config']['outstanding_rpcs_per_channel'] = DEEP
-    scenario['client_config']['client_channels'] = WIDE
+    scenario['client_config']['outstanding_rpcs_per_channel'] = deep
+    scenario['client_config']['client_channels'] = wide
     scenario['client_config']['async_client_threads'] = 0
   else:
     scenario['client_config']['outstanding_rpcs_per_channel'] = 1
     scenario['client_config']['client_channels'] = 1
     scenario['client_config']['async_client_threads'] = 1
 
+  if client_language:
+    # the CLIENT_LANGUAGE field is recognized by run_performance_tests.py
+    scenario['CLIENT_LANGUAGE'] = client_language
   if server_language:
     # the SERVER_LANGUAGE field is recognized by run_performance_tests.py
     scenario['SERVER_LANGUAGE'] = server_language
@@ -196,27 +212,27 @@ class CXXLanguage:
       yield _ping_pong_scenario(
           'cpp_protobuf_async_unary_qps_unconstrained_%s' % secstr, rpc_type='UNARY',
           client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-          use_unconstrained_client=True,
+          unconstrained_client='async',
           secure=secure,
           categories=smoketest_categories)
 
       yield _ping_pong_scenario(
           'cpp_protobuf_async_streaming_qps_unconstrained_%s' % secstr, rpc_type='STREAMING',
           client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-          use_unconstrained_client=True,
+          unconstrained_client='async',
           secure=secure)
 
       yield _ping_pong_scenario(
           'cpp_generic_async_streaming_qps_unconstrained_%s' % secstr, rpc_type='STREAMING',
           client_type='ASYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
-          use_unconstrained_client=True, use_generic_payload=True,
+          unconstrained_client='async', use_generic_payload=True,
           secure=secure,
           categories=smoketest_categories)
 
       yield _ping_pong_scenario(
           'cpp_generic_async_streaming_qps_one_server_core_%s' % secstr, rpc_type='STREAMING',
           client_type='ASYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
-          use_unconstrained_client=True, use_generic_payload=True,
+          unconstrained_client='async', use_generic_payload=True,
           server_core_limit=1, async_server_threads=1,
           secure=secure)
 
@@ -258,13 +274,13 @@ class CSharpLanguage:
     yield _ping_pong_scenario(
         'csharp_protobuf_async_unary_qps_unconstrained', rpc_type='UNARY',
         client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-        use_unconstrained_client=True,
+        unconstrained_client='async',
         categories=[SMOKETEST])
 
     yield _ping_pong_scenario(
         'csharp_protobuf_async_streaming_qps_unconstrained', rpc_type='STREAMING',
         client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-        use_unconstrained_client=True)
+        unconstrained_client='async')
 
     yield _ping_pong_scenario(
         'csharp_to_cpp_protobuf_sync_unary_ping_pong', rpc_type='UNARY',
@@ -277,6 +293,22 @@ class CSharpLanguage:
         client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
         server_language='c++', server_core_limit=1, async_server_threads=1)
 
+    yield _ping_pong_scenario(
+        'csharp_to_cpp_protobuf_async_unary_qps_unconstrained', rpc_type='UNARY',
+        client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
+        unconstrained_client='async', server_language='c++')
+
+    yield _ping_pong_scenario(
+        'csharp_to_cpp_protobuf_sync_to_async_unary_qps_unconstrained', rpc_type='UNARY',
+        client_type='SYNC_CLIENT', server_type='ASYNC_SERVER',
+        unconstrained_client='sync', server_language='c++')
+
+    yield _ping_pong_scenario(
+        'cpp_to_csharp_protobuf_async_unary_qps_unconstrained', rpc_type='UNARY',
+        client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
+        unconstrained_client='async', client_language='c++')
+
+
   def __str__(self):
     return 'csharp'
 
@@ -313,14 +345,14 @@ class NodeLanguage:
     yield _ping_pong_scenario(
         'node_protobuf_async_unary_qps_unconstrained', rpc_type='UNARY',
         client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-        use_unconstrained_client=True,
+        unconstrained_client='async',
         categories=[SMOKETEST])
 
     # TODO(jtattermusch): make this scenario work
     #yield _ping_pong_scenario(
     #    'node_protobuf_async_streaming_qps_unconstrained', rpc_type='STREAMING',
     #    client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-    #    use_unconstrained_client=True)
+    #    unconstrained_client='async')
 
     # TODO(jtattermusch): make this scenario work
     #yield _ping_pong_scenario(
@@ -369,19 +401,15 @@ class PythonLanguage:
         client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
         categories=[SMOKETEST])
 
-    # TODO(jtattermusch): 
-    # The qps_worker server gets thread starved with ~6400 threads, the GIL
-    # enforces that a single thread runs at a time, with no way to set thread
-    # priority.  Re-evaluate after changing DEEP and WIDE.
-    #yield _ping_pong_scenario(
-    #    'python_protobuf_sync_unary_qps_unconstrained', rpc_type='UNARY',
-    #    client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
-    #    use_unconstrained_client=True)
+    yield _ping_pong_scenario(
+        'python_protobuf_sync_unary_qps_unconstrained', rpc_type='UNARY',
+        client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
+        unconstrained_client='sync')
 
     yield _ping_pong_scenario(
         'python_protobuf_async_streaming_qps_unconstrained', rpc_type='STREAMING',
         client_type='ASYNC_CLIENT', server_type='SYNC_SERVER',
-        use_unconstrained_client=True)
+        unconstrained_client='async')
 
     yield _ping_pong_scenario(
         'python_to_cpp_protobuf_sync_unary_ping_pong', rpc_type='UNARY',
@@ -420,17 +448,15 @@ class RubyLanguage:
         client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
         categories=[SMOKETEST])
 
-    # TODO: scenario reports QPS of 0.0
-    #yield _ping_pong_scenario(
-    #    'ruby_protobuf_sync_unary_qps_unconstrained', rpc_type='UNARY',
-    #    client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
-    #    use_unconstrained_client=True)
+    yield _ping_pong_scenario(
+        'ruby_protobuf_sync_unary_qps_unconstrained', rpc_type='UNARY',
+        client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
+        unconstrained_client='sync')
 
-    # TODO: scenario reports QPS of 0.0
-    #yield _ping_pong_scenario(
-    #    'ruby_protobuf_sync_streaming_qps_unconstrained', rpc_type='STREAMING',
-    #    client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
-    #    use_unconstrained_client=True)
+    yield _ping_pong_scenario(
+        'ruby_protobuf_sync_streaming_qps_unconstrained', rpc_type='STREAMING',
+        client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
+        unconstrained_client='sync')
 
     yield _ping_pong_scenario(
         'ruby_to_cpp_protobuf_sync_unary_ping_pong', rpc_type='UNARY',
@@ -492,26 +518,26 @@ class JavaLanguage:
       yield _ping_pong_scenario(
           'java_protobuf_async_unary_qps_unconstrained_%s' % secstr, rpc_type='UNARY',
           client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-          use_unconstrained_client=True,
+          unconstrained_client='async',
           secure=secure, warmup_seconds=JAVA_WARMUP_SECONDS,
           categories=smoketest_categories)
 
       yield _ping_pong_scenario(
           'java_protobuf_async_streaming_qps_unconstrained_%s' % secstr, rpc_type='STREAMING',
           client_type='ASYNC_CLIENT', server_type='ASYNC_SERVER',
-          use_unconstrained_client=True,
+          unconstrained_client='async',
           secure=secure, warmup_seconds=JAVA_WARMUP_SECONDS)
 
       yield _ping_pong_scenario(
           'java_generic_async_streaming_qps_unconstrained_%s' % secstr, rpc_type='STREAMING',
           client_type='ASYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
-          use_unconstrained_client=True, use_generic_payload=True,
+          unconstrained_client='async', use_generic_payload=True,
           secure=secure, warmup_seconds=JAVA_WARMUP_SECONDS)
 
       yield _ping_pong_scenario(
           'java_generic_async_streaming_qps_one_server_core_%s' % secstr, rpc_type='STREAMING',
           client_type='ASYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
-          use_unconstrained_client=True, use_generic_payload=True,
+          unconstrained_client='async', use_generic_payload=True,
           async_server_threads=1,
           secure=secure, warmup_seconds=JAVA_WARMUP_SECONDS)
 
@@ -560,25 +586,28 @@ class GoLanguage:
           secure=secure,
           categories=smoketest_categories)
 
+      # unconstrained_client='async' is intended (client uses goroutines)
       yield _ping_pong_scenario(
           'go_protobuf_sync_unary_qps_unconstrained_%s' % secstr, rpc_type='UNARY',
           client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
-          use_unconstrained_client=True,
+          unconstrained_client='async',
           secure=secure,
           categories=smoketest_categories)
 
+      # unconstrained_client='async' is intended (client uses goroutines)
       yield _ping_pong_scenario(
           'go_protobuf_sync_streaming_qps_unconstrained_%s' % secstr, rpc_type='STREAMING',
           client_type='SYNC_CLIENT', server_type='SYNC_SERVER',
-          use_unconstrained_client=True,
+          unconstrained_client='async',
           secure=secure)
 
+      # unconstrained_client='async' is intended (client uses goroutines)
       # ASYNC_GENERIC_SERVER for Go actually uses a sync streaming server,
       # but that's mostly because of lack of better name of the enum value.
       yield _ping_pong_scenario(
           'go_generic_sync_streaming_qps_unconstrained_%s' % secstr, rpc_type='STREAMING',
           client_type='SYNC_CLIENT', server_type='ASYNC_GENERIC_SERVER',
-          use_unconstrained_client=True, use_generic_payload=True,
+          unconstrained_client='async', use_generic_payload=True,
           secure=secure)
 
       # TODO(jtattermusch): add scenarios go vs C++ 
diff --git a/tools/run_tests/run_interop_tests.py b/tools/run_tests/run_interop_tests.py
index e813473421..edbdf05e2a 100755
--- a/tools/run_tests/run_interop_tests.py
+++ b/tools/run_tests/run_interop_tests.py
@@ -82,10 +82,10 @@ class CXXLanguage:
     return {}
 
   def unimplemented_test_cases(self):
-    return _SKIP_ADVANCED + _SKIP_COMPRESSION
+    return _SKIP_ADVANCED
 
   def unimplemented_test_cases_server(self):
-    return _SKIP_ADVANCED + _SKIP_COMPRESSION
+    return _SKIP_ADVANCED
 
   def __str__(self):
     return 'c++'
diff --git a/tools/run_tests/run_performance_tests.py b/tools/run_tests/run_performance_tests.py
index a7728e7f7d..181d62bf4a 100755
--- a/tools/run_tests/run_performance_tests.py
+++ b/tools/run_tests/run_performance_tests.py
@@ -304,7 +304,11 @@ def create_scenarios(languages, workers_by_lang, remote_host=None, regex='.*',
           # 'SERVER_LANGUAGE' is an indicator for this script to pick
           # a server in different language.
           custom_server_lang = scenario_json.get('SERVER_LANGUAGE', None)
+          custom_client_lang = scenario_json.get('CLIENT_LANGUAGE', None)
           scenario_json = scenario_config.remove_nonproto_fields(scenario_json)
+          if custom_server_lang and custom_client_lang:
+            raise Exception('Cannot set both custom CLIENT_LANGUAGE and SERVER_LANGUAGE'
+                            'in the same scenario')
           if custom_server_lang:
             if not workers_by_lang.get(custom_server_lang, []):
               print 'Warning: Skipping scenario %s as' % scenario_json['name']
@@ -314,6 +318,16 @@ def create_scenarios(languages, workers_by_lang, remote_host=None, regex='.*',
             for idx in range(0, scenario_json['num_servers']):
               # replace first X workers by workers of a different language
               workers[idx] = workers_by_lang[custom_server_lang][idx]
+          if custom_client_lang:
+            if not workers_by_lang.get(custom_client_lang, []):
+              print 'Warning: Skipping scenario %s as' % scenario_json['name']
+              print('CLIENT_LANGUAGE is set to %s yet the language has '
+                    'not been selected with -l' % custom_client_lang)
+              continue
+            for idx in range(scenario_json['num_servers'], len(workers)):
+              # replace all client workers by workers of a different language,
+              # leave num_server workers as they are server workers.
+              workers[idx] = workers_by_lang[custom_client_lang][idx]
           scenario = create_scenario_jobspec(scenario_json,
                                              workers,
                                              remote_host=remote_host,
@@ -360,8 +374,8 @@ argp.add_argument('--bq_result_table', default=None, type=str,
                   help='Bigquery "dataset.table" to upload results to.')
 argp.add_argument('--category',
                   choices=['smoketest','all'],
-                  default='smoketest',
-                  help='Select a category of tests to run. Smoketest runs by default.')
+                  default='all',
+                  help='Select a category of tests to run.')
 argp.add_argument('--netperf',
                   default=False,
                   action='store_const',