Merge pull request #136 from ethereum/set-option

Introduce evmc_set_option_result enum

bindings/go/evmc/evmc.go

@@ -15,9 +15,9 @@ package evmc
 #include <stdlib.h>
 #include <string.h>
 
-static inline int set_option(struct evmc_instance* instance, char* name, char* value)
+static inline enum evmc_set_option_result set_option(struct evmc_instance* instance, char* name, char* value)
 {
-	int ret = evmc_set_option(instance, name, value);
+	enum evmc_set_option_result ret = evmc_set_option(instance, name, value);
 	free(name);
 	free(value);
 	return ret;
@@ -188,8 +188,12 @@ func (instance *Instance) Version() string {
 func (instance *Instance) SetOption(name string, value string) (err error) {
 
 	r := C.set_option(instance.handle, C.CString(name), C.CString(value))
-	if r != 1 {
+	switch r {
+	case C.EVMC_SET_OPTION_INVALID_NAME:
 		err = fmt.Errorf("evmc: option '%s' not accepted", name)
+	case C.EVMC_SET_OPTION_INVALID_VALUE:
+		err = fmt.Errorf("evmc: option '%s' has invalid value", name)
+	case C.EVMC_SET_OPTION_SUCCESS:
 	}
 	return err
 }

docs/EVMC.md

@@ -16,7 +16,7 @@ to access Ethereum environment and state.
    – a collection of utility functions for easier integration with EVMC.
 - [EVM Instructions](@ref instructions) 
    – the library with collection of metrics for EVM1 instruction set.
-- [EMVC VM Tester](@ref vmtester)
+- [EVMC VM Tester](@ref vmtester)
    – the EVMC-compatibility testing tool for VM implementations.
 
 

examples/example_vm.c

@@ -31,19 +31,21 @@ static void destroy(struct evmc_instance* evm)
 /// Example options.
 ///
 /// VMs are allowed to omit this function implementation.
-static int set_option(struct evmc_instance* instance, char const* name, char const* value)
+static enum evmc_set_option_result set_option(struct evmc_instance* instance,
+                                              char const* name,
+                                              char const* value)
 {
     struct example_vm* vm = (struct example_vm*)instance;
     if (strcmp(name, "verbose") == 0)
     {
         long int v = strtol(value, NULL, 0);
         if (v > INT_MAX || v < INT_MIN)
-            return 0;
+            return EVMC_SET_OPTION_INVALID_VALUE;
         vm->verbose = (int)v;
-        return 1;
+        return EVMC_SET_OPTION_SUCCESS;
     }
 
-    return 0;
+    return EVMC_SET_OPTION_INVALID_NAME;
 }
 
 static void release_result(struct evmc_result const* result)

include/evmc/evmc.h

@@ -654,6 +654,15 @@ struct evmc_instance;
  */
 typedef void (*evmc_destroy_fn)(struct evmc_instance* evm);
 
+/**
+ * Possible outcomes of evmc_set_option.
+ */
+enum evmc_set_option_result
+{
+    EVMC_SET_OPTION_SUCCESS = 0,
+    EVMC_SET_OPTION_INVALID_NAME = 1,
+    EVMC_SET_OPTION_INVALID_VALUE = 2
+};
 
 /**
  * Configures the EVM instance.
@@ -666,9 +675,11 @@ typedef void (*evmc_destroy_fn)(struct evmc_instance* evm);
  *  @param evm    The EVM instance to be configured.
  *  @param name   The option name. NULL-terminated string. Cannot be NULL.
  *  @param value  The new option value. NULL-terminated string. Cannot be NULL.
- *  @return       1 if the option set successfully, 0 otherwise.
+ *  @return       The outcome of the operation.
  */
-typedef int (*evmc_set_option_fn)(struct evmc_instance* evm, char const* name, char const* value);
+typedef enum evmc_set_option_result (*evmc_set_option_fn)(struct evmc_instance* evm,
+                                                          char const* name,
+                                                          char const* value);
 
 
 /**

include/evmc/helpers.h

@@ -56,13 +56,13 @@ static inline void evmc_destroy(struct evmc_instance* instance)
  *
  * @see evmc_set_option_fn
  */
-static inline int evmc_set_option(struct evmc_instance* instance,
+static inline enum evmc_set_option_result evmc_set_option(struct evmc_instance* instance,
                                                           char const* name,
                                                           char const* value)
 {
     if (instance->set_option)
         return instance->set_option(instance, name, value);
-    return 0;
+    return EVMC_SET_OPTION_INVALID_NAME;
 }
 
 /**

test/vmtester/tests.cpp

@@ -64,10 +64,10 @@ TEST_F(evmc_vm_test, set_option_unknown)
 {
     if (vm->set_option)
     {
-        int r = vm->set_option(vm, "unknown_option_csk9twq", "v");
-        EXPECT_EQ(r, 0);
+        enum evmc_set_option_result r = vm->set_option(vm, "unknown_option_csk9twq", "v");
+        EXPECT_EQ(r, EVMC_SET_OPTION_INVALID_NAME);
         r = vm->set_option(vm, "unknown_option_csk9twq", "x");
-        EXPECT_EQ(r, 0);
+        EXPECT_EQ(r, EVMC_SET_OPTION_INVALID_NAME);
     }
 }
 
@@ -75,8 +75,8 @@ TEST_F(evmc_vm_test, set_option_empty_value)
 {
     if (vm->set_option)
     {
-        int r = vm->set_option(vm, "unknown_option_csk9twq", nullptr);
-        EXPECT_EQ(r, 0);
+        enum evmc_set_option_result r = vm->set_option(vm, "unknown_option_csk9twq", nullptr);
+        EXPECT_EQ(r, EVMC_SET_OPTION_INVALID_NAME);
     }
 }