Merge pull request #125 from ethereum/host-interface

Host interface

bindings/go/evmc/evmc.go

@@ -29,7 +29,7 @@ struct extended_context
 	int64_t index;
 };
 
-extern const struct evmc_context_fn_table evmc_go_fn_table;
+extern const struct evmc_host_interface evmc_go_host;
 
 static struct evmc_result execute_wrapper(struct evmc_instance* instance, int64_t context_index, enum evmc_revision rev,
 	const struct evmc_address* destination, const struct evmc_address* sender, const struct evmc_uint256be* value,
@@ -51,7 +51,7 @@ static struct evmc_result execute_wrapper(struct evmc_instance* instance, int64_
 		flags,
 	};
 
-	struct extended_context ctx = {{&evmc_go_fn_table}, context_index};
+	struct extended_context ctx = {{&evmc_go_host}, context_index};
 	return evmc_execute(instance, &ctx.context, rev, &msg, code, code_size);
 }
 */

bindings/go/evmc/host.c

@@ -20,7 +20,7 @@ void evmc_go_free_result_output(const struct evmc_result* result)
  * problem the go_exported_functions_type_checks() function simulates usage
  * of Go exported functions with expected types to check them during compilation.
  */
-const struct evmc_context_fn_table evmc_go_fn_table = {
+const struct evmc_host_interface evmc_go_host = {
     (evmc_account_exists_fn)accountExists,
     (evmc_get_storage_fn)getStorage,
     (evmc_set_storage_fn)setStorage,

examples/example_host.cpp

@@ -129,14 +129,14 @@ static void emit_log(evmc_context* context,
     (void)topics_count;
 }
 
-static const evmc_context_fn_table methods = {
+static const evmc_host_interface interface = {
     account_exists, get_storage,  set_storage, get_balance,    get_code_size,  get_code_hash,
     copy_code,      selfdestruct, call,        get_tx_context, get_block_hash, emit_log,
 };
 
 struct example_host_context : evmc_context
 {
-    example_host_context() : evmc_context{&methods} {}
+    example_host_context() : evmc_context{&interface} {}
 };
 
 extern "C" {

examples/example_vm.c

@@ -108,9 +108,9 @@ static struct evmc_result execute(struct evmc_instance* instance,
     {
         struct evmc_uint256be value;
         const struct evmc_uint256be index = {{0}};
-        context->fn_table->get_storage(&value, context, &msg->destination, &index);
+        context->host->get_storage(&value, context, &msg->destination, &index);
         value.bytes[31]++;
-        context->fn_table->set_storage(context, &msg->destination, &index, &value);
+        context->host->set_storage(context, &msg->destination, &index, &value);
         ret.status_code = EVMC_SUCCESS;
         return ret;
     }

include/evmc/evmc.h

@@ -579,14 +579,14 @@ typedef struct evmc_result (*evmc_call_fn)(struct evmc_context* context,
                                            const struct evmc_message* msg);
 
 /**
- * The context interface.
+ * The Host interface.
  *
- *  The set of all callback functions expected by EVM instances. This is C
- *  realisation of vtable for OOP interface (only virtual methods, no data).
- *  Host implementations SHOULD create constant singletons of this (similarly
- *  to vtables) to lower the maintenance and memory management cost.
+ * The set of all callback functions expected by VM instances. This is C
+ * realisation of vtable for OOP interface (only virtual methods, no data).
+ * Host implementations SHOULD create constant singletons of this (similarly
+ * to vtables) to lower the maintenance and memory management cost.
  */
-struct evmc_context_fn_table
+struct evmc_host_interface
 {
     /** Check account existence callback function. */
     evmc_account_exists_fn account_exists;
@@ -638,8 +638,8 @@ struct evmc_context_fn_table
  */
 struct evmc_context
 {
-    /** Function table defining the context interface (vtable). */
-    const struct evmc_context_fn_table* fn_table;
+    /** The Host interface. */
+    const struct evmc_host_interface* host;
 };