Change grpc_channel_filter init_call_elem() method to return grpc_error.

17 files changed, 100 insertions, 56 deletions

diff --git a/src/core/ext/census/grpc_filter.c b/src/core/ext/census/grpc_filter.c
index 72e4e5427e..dd2e2e0124 100644
--- a/src/core/ext/census/grpc_filter.c
+++ b/src/core/ext/census/grpc_filter.c
@@ -124,13 +124,14 @@ static void server_start_transport_op(grpc_exec_ctx *exec_ctx,
   grpc_call_next_op(exec_ctx, elem, op);
 }
 
-static void client_init_call_elem(grpc_exec_ctx *exec_ctx,
-                                  grpc_call_element *elem,
-                                  grpc_call_element_args *args) {
+static grpc_error* client_init_call_elem(grpc_exec_ctx *exec_ctx,
+                                         grpc_call_element *elem,
+                                         grpc_call_element_args *args) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   memset(d, 0, sizeof(*d));
   d->start_ts = gpr_now(GPR_CLOCK_REALTIME);
+  return GRPC_ERROR_NONE;
 }
 
 static void client_destroy_call_elem(grpc_exec_ctx *exec_ctx,
@@ -142,15 +143,16 @@ static void client_destroy_call_elem(grpc_exec_ctx *exec_ctx,
   /* TODO(hongyu): record rpc client stats and census_rpc_end_op here */
 }
 
-static void server_init_call_elem(grpc_exec_ctx *exec_ctx,
-                                  grpc_call_element *elem,
-                                  grpc_call_element_args *args) {
+static grpc_error* server_init_call_elem(grpc_exec_ctx *exec_ctx,
+                                         grpc_call_element *elem,
+                                         grpc_call_element_args *args) {
   call_data *d = elem->call_data;
   GPR_ASSERT(d != NULL);
   memset(d, 0, sizeof(*d));
   d->start_ts = gpr_now(GPR_CLOCK_REALTIME);
   /* TODO(hongyu): call census_tracing_start_op here. */
   grpc_closure_init(&d->finish_recv, server_on_done_recv, elem);
+  return GRPC_ERROR_NONE;
 }
 
 static void server_destroy_call_elem(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/ext/client_config/client_channel.c b/src/core/ext/client_config/client_channel.c
index 1d5a7d5224..b0a09dab93 100644
--- a/src/core/ext/client_config/client_channel.c
+++ b/src/core/ext/client_config/client_channel.c
@@ -430,10 +430,12 @@ static int cc_pick_subchannel(grpc_exec_ctx *exec_ctx, void *elemp,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   grpc_subchannel_call_holder_init(elem->call_data, cc_pick_subchannel, elem,
                                    args->call_stack);
+  return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data */
diff --git a/src/core/ext/client_config/subchannel.c b/src/core/ext/client_config/subchannel.c
index 468067ea57..2e9cf7d7d4 100644
--- a/src/core/ext/client_config/subchannel.c
+++ b/src/core/ext/client_config/subchannel.c
@@ -709,8 +709,11 @@ grpc_subchannel_call *grpc_connected_subchannel_create_call(
   grpc_call_stack *callstk = SUBCHANNEL_CALL_TO_CALL_STACK(call);
   call->connection = con;
   GRPC_CONNECTED_SUBCHANNEL_REF(con, "subchannel_call");
-  grpc_call_stack_init(exec_ctx, chanstk, 1, subchannel_call_destroy, call,
-                       NULL, NULL, callstk);
+  grpc_error* error = grpc_call_stack_init(exec_ctx, chanstk, 1,
+                                           subchannel_call_destroy, call,
+                                           NULL, NULL, callstk);
+// FIXME: handle error (probably requires changing this function's API)
+GPR_ASSERT(error == GRPC_ERROR_NONE);
   grpc_call_stack_set_pollset_or_pollset_set(exec_ctx, callstk, pollent);
   return call;
 }
diff --git a/src/core/ext/load_reporting/load_reporting_filter.c b/src/core/ext/load_reporting/load_reporting_filter.c
index f372f88c3a..cfe752d6e2 100644
--- a/src/core/ext/load_reporting/load_reporting_filter.c
+++ b/src/core/ext/load_reporting/load_reporting_filter.c
@@ -56,10 +56,12 @@ static void invoke_lr_fn_locked(grpc_load_reporting_config *lrc,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   memset(calld, 0, sizeof(call_data));
+  return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data */
diff --git a/src/core/lib/channel/channel_stack.c b/src/core/lib/channel/channel_stack.c
index bbba85d80b..0613f94c29 100644
--- a/src/core/lib/channel/channel_stack.c
+++ b/src/core/lib/channel/channel_stack.c
@@ -157,12 +157,13 @@ void grpc_channel_stack_destroy(grpc_exec_ctx *exec_ctx,
   }
 }
 
-void grpc_call_stack_init(grpc_exec_ctx *exec_ctx,
-                          grpc_channel_stack *channel_stack, int initial_refs,
-                          grpc_iomgr_cb_func destroy, void *destroy_arg,
-                          grpc_call_context_element *context,
-                          const void *transport_server_data,
-                          grpc_call_stack *call_stack) {
+grpc_error* grpc_call_stack_init(grpc_exec_ctx *exec_ctx,
+                                 grpc_channel_stack *channel_stack,
+                                 int initial_refs, grpc_iomgr_cb_func destroy,
+                                 void *destroy_arg,
+                                 grpc_call_context_element *context,
+                                 const void *transport_server_data,
+                                 grpc_call_stack *call_stack) {
   grpc_channel_element *channel_elems = CHANNEL_ELEMS_FROM_STACK(channel_stack);
   grpc_call_element_args args;
   size_t count = channel_stack->count;
@@ -185,10 +186,14 @@ void grpc_call_stack_init(grpc_exec_ctx *exec_ctx,
     call_elems[i].filter = channel_elems[i].filter;
     call_elems[i].channel_data = channel_elems[i].channel_data;
     call_elems[i].call_data = user_data;
-    call_elems[i].filter->init_call_elem(exec_ctx, &call_elems[i], &args);
+    grpc_error* error = call_elems[i].filter->init_call_elem(
+        exec_ctx, &call_elems[i], &args);
+    if (error != GRPC_ERROR_NONE)
+      return error;
     user_data +=
         ROUND_UP_TO_ALIGNMENT_SIZE(call_elems[i].filter->sizeof_call_data);
   }
+  return GRPC_ERROR_NONE;
 }
 
 void grpc_call_stack_set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/channel/channel_stack.h b/src/core/lib/channel/channel_stack.h
index 41dd4a0d8a..f56c654067 100644
--- a/src/core/lib/channel/channel_stack.h
+++ b/src/core/lib/channel/channel_stack.h
@@ -110,8 +110,9 @@ typedef struct {
      on a client; if it is non-NULL, then it points to memory owned by the
      transport and is on the server. Most filters want to ignore this
      argument. */
-  void (*init_call_elem)(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                         grpc_call_element_args *args);
+  grpc_error* (*init_call_elem)(grpc_exec_ctx *exec_ctx,
+                                grpc_call_element *elem,
+                                grpc_call_element_args *args);
   void (*set_pollset_or_pollset_set)(grpc_exec_ctx *exec_ctx,
                                      grpc_call_element *elem,
                                      grpc_polling_entity *pollent);
@@ -209,12 +210,13 @@ void grpc_channel_stack_destroy(grpc_exec_ctx *exec_ctx,
 /* Initialize a call stack given a channel stack. transport_server_data is
    expected to be NULL on a client, or an opaque transport owned pointer on the
    server. */
-void grpc_call_stack_init(grpc_exec_ctx *exec_ctx,
-                          grpc_channel_stack *channel_stack, int initial_refs,
-                          grpc_iomgr_cb_func destroy, void *destroy_arg,
-                          grpc_call_context_element *context,
-                          const void *transport_server_data,
-                          grpc_call_stack *call_stack);
+grpc_error* grpc_call_stack_init(grpc_exec_ctx *exec_ctx,
+                                 grpc_channel_stack *channel_stack,
+                                 int initial_refs, grpc_iomgr_cb_func destroy,
+                                 void *destroy_arg,
+                                 grpc_call_context_element *context,
+                                 const void *transport_server_data,
+                                 grpc_call_stack *call_stack);
 /* Set a pollset or a pollset_set for a call stack: must occur before the first
  * op is started */
 void grpc_call_stack_set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/channel/compress_filter.c b/src/core/lib/channel/compress_filter.c
index 32ebe53ee6..bcc8e17a9d 100644
--- a/src/core/lib/channel/compress_filter.c
+++ b/src/core/lib/channel/compress_filter.c
@@ -256,8 +256,9 @@ static void compress_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
 
@@ -266,6 +267,8 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
   calld->has_compression_algorithm = 0;
   grpc_closure_init(&calld->got_slice, got_slice, elem);
   grpc_closure_init(&calld->send_done, send_done, elem);
+
+  return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data */
diff --git a/src/core/lib/channel/connected_channel.c b/src/core/lib/channel/connected_channel.c
index 0a7d27a1dc..8dde688df2 100644
--- a/src/core/lib/channel/connected_channel.c
+++ b/src/core/lib/channel/connected_channel.c
@@ -81,16 +81,17 @@ static void con_start_transport_op(grpc_exec_ctx *exec_ctx,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
-  int r;
-
-  r = grpc_transport_init_stream(
+  int r = grpc_transport_init_stream(
       exec_ctx, chand->transport, TRANSPORT_STREAM_FROM_CALL_DATA(calld),
       &args->call_stack->refcount, args->server_transport_data);
-  GPR_ASSERT(r == 0);
+  return r == 0
+         ? GRPC_ERROR_NONE
+         : GRPC_ERROR_CREATE("transport initialization failed");
 }
 
 static void set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/channel/http_client_filter.c b/src/core/lib/channel/http_client_filter.c
index ab6c6c9ef0..30f4ed1f6f 100644
--- a/src/core/lib/channel/http_client_filter.c
+++ b/src/core/lib/channel/http_client_filter.c
@@ -169,11 +169,13 @@ static void hc_start_transport_op(grpc_exec_ctx *exec_ctx,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   calld->on_done_recv = NULL;
   grpc_closure_init(&calld->hc_on_recv, hc_on_recv, elem);
+  return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data */
diff --git a/src/core/lib/channel/http_server_filter.c b/src/core/lib/channel/http_server_filter.c
index d0beebd817..960d1ce45e 100644
--- a/src/core/lib/channel/http_server_filter.c
+++ b/src/core/lib/channel/http_server_filter.c
@@ -224,13 +224,15 @@ static void hs_start_transport_op(grpc_exec_ctx *exec_ctx,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   /* initialize members */
   memset(calld, 0, sizeof(*calld));
   grpc_closure_init(&calld->hs_on_recv, hs_on_recv, elem);
+  return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data */
diff --git a/src/core/lib/security/transport/client_auth_filter.c b/src/core/lib/security/transport/client_auth_filter.c
index 76be2acd72..6179b9e18c 100644
--- a/src/core/lib/security/transport/client_auth_filter.c
+++ b/src/core/lib/security/transport/client_auth_filter.c
@@ -264,10 +264,12 @@ static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   memset(calld, 0, sizeof(*calld));
+  return GRPC_ERROR_NONE;
 }
 
 static void set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/security/transport/server_auth_filter.c b/src/core/lib/security/transport/server_auth_filter.c
index 12e789bde9..379247131b 100644
--- a/src/core/lib/security/transport/server_auth_filter.c
+++ b/src/core/lib/security/transport/server_auth_filter.c
@@ -199,8 +199,9 @@ static void auth_start_transport_op(grpc_exec_ctx *exec_ctx,
 }
 
 /* Constructor for call_data */
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   /* grab pointers to our data from the call element */
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
@@ -222,6 +223,8 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
   args->context[GRPC_CONTEXT_SECURITY].value = server_ctx;
   args->context[GRPC_CONTEXT_SECURITY].destroy =
       grpc_server_security_context_destroy;
+
+  return GRPC_ERROR_NONE;
 }
 
 /* Destructor for call_data */
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 04291b0ee0..d64ca64a15 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -262,9 +262,12 @@ grpc_call *grpc_call_create(
   call->send_deadline = send_deadline;
   GRPC_CHANNEL_INTERNAL_REF(channel, "call");
   /* initial refcount dropped by grpc_call_destroy */
-  grpc_call_stack_init(&exec_ctx, channel_stack, 1, destroy_call, call,
-                       call->context, server_transport_data,
-                       CALL_STACK_FROM_CALL(call));
+  grpc_error* error = grpc_call_stack_init(&exec_ctx, channel_stack, 1,
+                                           destroy_call, call, call->context,
+                                           server_transport_data,
+                                           CALL_STACK_FROM_CALL(call));
+// FIXME: handle error (probably requires changing this function's API)
+GPR_ASSERT(error == GRPC_ERROR_NONE);
   if (cq != NULL) {
     GPR_ASSERT(
         pollset_set_alternative == NULL &&
diff --git a/src/core/lib/surface/lame_client.c b/src/core/lib/surface/lame_client.c
index 5ea4cba5d1..7d9168f2e0 100644
--- a/src/core/lib/surface/lame_client.c
+++ b/src/core/lib/surface/lame_client.c
@@ -107,8 +107,11 @@ static void lame_start_transport_op(grpc_exec_ctx *exec_ctx,
   GRPC_ERROR_UNREF(op->disconnect_with_error);
 }
 
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {}
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
+  return GRPC_ERROR_NONE;
+}
 
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
                               const grpc_call_stats *stats,
diff --git a/src/core/lib/surface/server.c b/src/core/lib/surface/server.c
index def6e5068b..0a0c224b4d 100644
--- a/src/core/lib/surface/server.c
+++ b/src/core/lib/surface/server.c
@@ -848,8 +848,9 @@ static void channel_connectivity_changed(grpc_exec_ctx *exec_ctx, void *cd,
   }
 }
 
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
   memset(calld, 0, sizeof(call_data));
@@ -861,6 +862,7 @@ static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
                     server_on_recv_initial_metadata, elem);
 
   server_ref(chand->server);
+  return GRPC_ERROR_NONE;
 }
 
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
diff --git a/test/core/channel/channel_stack_test.c b/test/core/channel/channel_stack_test.c
index f9561bed70..9c6a47eb52 100644
--- a/test/core/channel/channel_stack_test.c
+++ b/test/core/channel/channel_stack_test.c
@@ -53,10 +53,12 @@ static void channel_init_func(grpc_exec_ctx *exec_ctx,
   *(int *)(elem->channel_data) = 0;
 }
 
-static void call_init_func(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {
+static grpc_error* call_init_func(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
   ++*(int *)(elem->channel_data);
   *(int *)(elem->call_data) = 0;
+  return GRPC_ERROR_NONE;
 }
 
 static void channel_destroy_func(grpc_exec_ctx *exec_ctx,
@@ -132,8 +134,10 @@ static void test_create_channel_stack(void) {
   GPR_ASSERT(*channel_data == 0);
 
   call_stack = gpr_malloc(channel_stack->call_stack_size);
-  grpc_call_stack_init(&exec_ctx, channel_stack, 1, free_call, call_stack, NULL,
-                       NULL, call_stack);
+  grpc_error* error = grpc_call_stack_init(&exec_ctx, channel_stack, 1,
+                                           free_call, call_stack, NULL, NULL,
+                                           call_stack);
+  GPR_ASSERT(error == GRPC_ERROR_NONE);
   GPR_ASSERT(call_stack->count == 1);
   call_elem = grpc_call_stack_element(call_stack, 0);
   GPR_ASSERT(call_elem->filter == channel_elem->filter);
diff --git a/test/core/end2end/tests/filter_causes_close.c b/test/core/end2end/tests/filter_causes_close.c
index 526c05ca3e..3ff0abed63 100644
--- a/test/core/end2end/tests/filter_causes_close.c
+++ b/test/core/end2end/tests/filter_causes_close.c
@@ -233,8 +233,11 @@ static void start_transport_stream_op(grpc_exec_ctx *exec_ctx,
   grpc_call_next_op(exec_ctx, elem, op);
 }
 
-static void init_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
-                           grpc_call_element_args *args) {}
+static grpc_error* init_call_elem(grpc_exec_ctx *exec_ctx,
+                                  grpc_call_element *elem,
+                                  grpc_call_element_args *args) {
+  return GRPC_ERROR_NONE;
+}
 
 static void destroy_call_elem(grpc_exec_ctx *exec_ctx, grpc_call_element *elem,
                               const grpc_call_stats *stats,