Merge pull request ethereum#111 from ethereum/go-host-type-checks

go: Add Host exported functions type checks

bindings/go/evmc/host.c

@@ -7,6 +7,19 @@
 
 #include <stdlib.h>
 
+
+void evmc_go_free_result_output(const struct evmc_result* result)
+{
+    free((void*)result->output_data);
+}
+
+
+/* Go does not support exporting functions with parameters with const modifiers,
+ * so we have to cast function pointers to the function types defined in EVMC.
+ * This disables any type checking of exported Go functions. To mitigate this
+ * 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 = {
     (evmc_account_exists_fn)accountExists,
     (evmc_get_storage_fn)getStorage,
@@ -22,7 +35,70 @@ const struct evmc_context_fn_table evmc_go_fn_table = {
     (evmc_emit_log_fn)emitLog,
 };
 
-void evmc_go_free_result_output(const struct evmc_result* result)
+
+#pragma GCC diagnostic error "-Wconversion"
+static inline void go_exported_functions_type_checks()
 {
-    free((void*)result->output_data);
+    struct evmc_context* context = NULL;
+    struct evmc_address* address = NULL;
+    struct evmc_uint256be* uint256be = NULL;
+    uint8_t* data = NULL;
+    size_t size = 0;
+    int64_t number = 0;
+    struct evmc_message* message = NULL;
+    struct evmc_result* result = NULL;
+    struct evmc_tx_context* tx_context = NULL;
+
+    enum evmc_storage_status storage_status;
+    (void)storage_status;
+    int status;
+    (void)status;
+
+    evmc_account_exists_fn account_exists_fn = NULL;
+    status = account_exists_fn(context, address);
+    status = accountExists(context, address);
+
+    evmc_get_storage_fn get_storage_fn = NULL;
+    get_storage_fn(uint256be, context, address, uint256be);
+    getStorage(uint256be, context, address, uint256be);
+
+    evmc_set_storage_fn set_storage_fn = NULL;
+    storage_status = set_storage_fn(context, address, uint256be, uint256be);
+    storage_status = setStorage(context, address, uint256be, uint256be);
+
+    evmc_get_balance_fn get_balance_fn = NULL;
+    get_balance_fn(uint256be, context, address);
+    getBalance(uint256be, context, address);
+
+    evmc_get_code_size_fn get_code_size_fn = NULL;
+    size = get_code_size_fn(context, address);
+    size = getCodeSize(context, address);
+
+    evmc_get_code_hash_fn get_code_hash_fn = NULL;
+    get_code_hash_fn(uint256be, context, address);
+    getCodeHash(uint256be, context, address);
+
+    evmc_copy_code_fn copy_code_fn = NULL;
+    size = copy_code_fn(context, address, size, data, size);
+    size = copyCode(context, address, size, data, size);
+
+    evmc_selfdestruct_fn selfdestruct_fn = NULL;
+    selfdestruct_fn(context, address, address);
+    selfdestruct(context, address, address);
+
+    evmc_call_fn call_fn = NULL;
+    call_fn(result, context, message);
+    call(result, context, message);
+
+    evmc_get_tx_context_fn get_tx_context_fn = NULL;
+    get_tx_context_fn(tx_context, context);
+    getTxContext(tx_context, context);
+
+    evmc_get_block_hash_fn get_block_hash_fn = NULL;
+    get_block_hash_fn(uint256be, context, number);
+    getBlockHash(uint256be, context, number);
+
+    evmc_emit_log_fn emit_log_fn = NULL;
+    emit_log_fn(context, address, data, size, uint256be, size);
+    emitLog(context, address, data, size, uint256be, size);
 }