EVM-C: Rename evm_result_code -> evm_status_code

examples/capi.c

@@ -112,7 +112,7 @@ static void evm_log(struct evm_context* context, const struct evm_uint160be* add
     printf("EVM-C: LOG%d\n", (int)topics_count);
 }
 
-static const struct evm_host example_host = {
+static const struct evm_context_fn_table ctx_fn_table = {
     account_exists,
     get_storage,
     set_storage,
@@ -139,11 +139,13 @@ int main(int argc, char *argv[]) {
     struct evm_uint160be addr = {{0, 1, 2,}};
     int64_t gas = 200000;
 
+    struct evm_context ctx = {&ctx_fn_table};
+
     struct evm_message msg = {addr, addr, value, input, sizeof(input),
                               code_hash, gas, 0};
 
     struct evm_result result =
-        jit->execute(jit, NULL, EVM_HOMESTEAD, &msg, code, code_size);
+        jit->execute(jit, &ctx, EVM_HOMESTEAD, &msg, code, code_size);
 
     printf("Execution result:\n");
     if (result.code != EVM_SUCCESS) {

examples/examplevm.c

@@ -1,15 +1,15 @@
+#include <evm.h>
+
+#include <limits.h>
+#include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <limits.h>
-#include <evm.h>
 
 
 struct examplevm
 {
     struct evm_instance instance;
-    const struct evm_host* host;
+    int verbose;
-
-    int example_option;
 };
 
 static void evm_destroy(struct evm_instance* evm)
@@ -25,11 +25,11 @@ int evm_set_option(struct evm_instance* instance,
                    char const* value)
 {
     struct examplevm* vm = (struct examplevm*)instance;
-    if (strcmp(name, "example-option") == 0) {
+    if (strcmp(name, "verbose") == 0) {
         long int v = strtol(value, NULL, 0);
         if (v > INT_MAX || v < INT_MIN)
             return 0;
-        vm->example_option = (int)v;
+        vm->verbose = (int)v;
         return 1;
     }
 
@@ -77,7 +77,7 @@ static struct evm_result execute(struct evm_instance* instance,
     const char counter[] = "600160005401600055";
 
     if (code_size == strlen(return_address) &&
-        strncmp((const char*)code, return_address, code_size)) {
+        strncmp((const char*)code, return_address, code_size) == 0) {
         static const size_t address_size = sizeof(msg->address);
         uint8_t* output_data = (uint8_t*)malloc(address_size);
         if (!output_data) {
@@ -93,12 +93,12 @@ static struct evm_result execute(struct evm_instance* instance,
         return ret;
     }
     else if (code_size == strlen(counter) &&
-        strncmp((const char*)code, counter, code_size)) {
+        strncmp((const char*)code, counter, code_size) == 0) {
         struct evm_uint256be value;
         const struct evm_uint256be index = {{0,}};
-        vm->host->get_storage(&value, context, &msg->address, &index);
+        context->fn_table->get_storage(&value, context, &msg->address, &index);
         value.bytes[31] += 1;
-        vm->host->set_storage(context, &msg->address, &index, &value);
+        context->fn_table->set_storage(context, &msg->address, &index, &value);
         ret.code = EVM_SUCCESS;
         return ret;
     }
@@ -107,6 +107,9 @@ static struct evm_result execute(struct evm_instance* instance,
     ret.code = EVM_FAILURE;
     ret.gas_left = 0;
 
+    if (vm->verbose)
+        printf("Execution done.\n");
+
     return ret;
 }
 

include/evm.h

@@ -98,8 +98,8 @@ typedef void (*evm_get_block_hash_fn)(struct evm_uint256be* result,
                                       struct evm_context* context,
                                       int64_t number);
 
-/// The execution result code.
+/// The execution status code.
-enum evm_result_code {
+enum evm_status_code {
     EVM_SUCCESS = 0,               ///< Execution finished with success.
     EVM_FAILURE = 1,               ///< Generic execution failure.
     EVM_OUT_OF_GAS = 2,
@@ -107,7 +107,7 @@ enum evm_result_code {
     EVM_BAD_JUMP_DESTINATION = 4,
     EVM_STACK_OVERFLOW = 5,
     EVM_STACK_UNDERFLOW = 6,
-    EVM_REVERT = 7,  ///< Execution terminated with REVERT opcode.
+    EVM_REVERT = 7,                ///< Execution terminated with REVERT opcode.
 
     /// EVM implementation internal error.
     ///
@@ -132,7 +132,7 @@ typedef void (*evm_release_result_fn)(struct evm_result const* result);
 struct evm_result {
     /// The execution result code.
     /// FIXME: Rename to 'status' or 'status_code'.
-    enum evm_result_code code;
+    enum evm_status_code code;
 
     /// The amount of gas left after the execution.
     ///
@@ -295,13 +295,13 @@ typedef void (*evm_call_fn)(struct evm_result* result,
                             struct evm_context* context,
                             const struct evm_message* msg);
 
-/// The Host interface.
+/// The context interface.
 ///
 /// The set of all callback functions expected by EVM instances. This is C
-/// realisation of OOP interface (only virtual methods, no data).
+/// 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 evm_host {
+struct evm_context_fn_table {
     evm_account_exists_fn account_exists;
     evm_get_storage_fn get_storage;
     evm_set_storage_fn set_storage;
@@ -325,8 +325,8 @@ struct evm_host {
 /// Optionally, The Host MAY include in the context additional data.
 struct evm_context {
 
-    /// Function table defining the context interface.
+    /// Function table defining the context interface (vtable).
-    const struct evm_host* fn_table;
+    const struct evm_context_fn_table* fn_table;
 };
 
 
@@ -434,6 +434,8 @@ struct evm_instance {
     ///
     /// For future use to detect ABI incompatibilities. The EVM-C ABI version
     /// represented by this file is in ::EVM_ABI_VERSION.
+    ///
+    /// @todo Consider removing this field.
     const int abi_version;
 
     /// Pointer to function destroying the EVM instance.
@@ -467,7 +469,6 @@ struct evm_instance {
 ///
 /// @return  EVM instance.
 /// @todo Specify if this function can return null pointer to indicate error.
-/// @todo Can we return const pointer?
 struct evm_instance* examplevm_create(void);