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Merge pull request #78: EVM-C: description fixes and ExampleVM

This commit is contained in:
Paweł Bylica 2016-08-23 09:26:29 +02:00 committed by GitHub
parent 6c4089ad80 8c2f9d44e8
commit 82f89664a0
4 changed files with 164 additions and 13 deletions
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8
examples/CMakeLists.txt
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@ -1,2 +1,6 @@
add_library(example-capi STATIC EXCLUDE_FROM_ALL capi.c)
target_include_directories(example-capi PRIVATE ../include)
add_library(example-vm STATIC EXCLUDE_FROM_ALL examplevm.c)
target_include_directories(example-vm PRIVATE ../include)
add_executable(example-capi EXCLUDE_FROM_ALL capi.c)
target_include_directories(example-capi PRIVATE ../include)
target_link_libraries(example-capi PRIVATE example-vm)

67
examples/capi.c
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@ -1,11 +1,25 @@
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "evm.h"
struct evm_uint256 balance(struct evm_env*, struct evm_hash160 address);
struct evm_uint256 balance(struct evm_env* env, struct evm_hash160 address)
{
struct evm_uint256 ret = { .words = { 1 } };
return ret;
}
struct evm_hash160 address(struct evm_env* env)
{
struct evm_hash160 ret = { .bytes = { 1, 2, 3, 4 } };
return ret;
}
union evm_variant query(struct evm_env* env,
enum evm_query_key key,
union evm_variant arg) {
union evm_variant result;
printf("EVM-C: QUERY %d\n", key);
switch (key) {
case EVM_GAS_LIMIT: result.int64 = 314; break;
@ -13,25 +27,70 @@ union evm_variant query(struct evm_env* env,
result.uint256 = balance(env, arg.address);
break;
case EVM_ADDRESS:
result.address = address(env);
break;
default: result.int64 = 0; break;
}
return result;
}
void update(struct evm_env* env,
enum evm_update_key key,
union evm_variant arg1,
union evm_variant arg2)
{
printf("EVM-C: UPDATE %d\n", key);
}
int64_t call(
struct evm_env* _opaqueEnv,
enum evm_call_kind _kind,
int64_t _gas,
struct evm_hash160 _address,
struct evm_uint256 _value,
uint8_t const* _inputData,
size_t _inputSize,
uint8_t* _outputData,
size_t _outputSize
)
{
printf("EVM-C: CALL %d\n", _kind);
return EVM_EXCEPTION;
}
/// Example how the API is supposed to be used.
void example() {
struct evm_instance* jit = evm_create(query, 0, 0);
int main(int argc, char *argv[]) {
printf("Using VM: %s (%s)\n", evm_get_info(EVM_NAME), evm_get_info(EVM_VERSION));
struct evm_instance* jit = evm_create(query, update, call);
char const code[] = "exec()";
const size_t code_size = sizeof(code);
struct evm_hash256 code_hash = {.words = {1, 2, 3}};
char const input[] = "Hello World!";
struct evm_uint256 value = {{1, 0, 0, 0}};
int64_t gas = 200000;
struct evm_result result =
evm_execute(jit, NULL, code_hash, code, sizeof(code), gas, input,
evm_execute(jit, NULL, EVM_HOMESTEAD, code_hash, (const uint8_t *)code, code_size, gas, (const uint8_t *)input,
sizeof(input), value);
printf("Execution result:\n");
if (result.gas_left & EVM_EXCEPTION) {
printf(" EVM eception\n");
}
printf(" Gas used: %lld\n", gas - result.gas_left);
printf(" Gas left: %lld\n", result.gas_left);
printf(" Output size: %zd\n", result.output_size);
printf(" Output: ");
for (int i = 0; i < result.output_size; i++) {
printf("%02x ", result.output_data[i]);
}
printf("\n");
evm_destroy_result(result);
evm_destroy(jit);
}

88
examples/examplevm.c Normal file
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@ -0,0 +1,88 @@
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include "evm.h"
struct evm_instance {
evm_query_fn query_fn;
evm_update_fn update_fn;
evm_call_fn call_fn;
};
EXPORT char const* evm_get_info(enum evm_info_key key)
{
switch(key) {
case EVM_NAME: return "ExampleVM"; break;
case EVM_VERSION: return "git"; break;
}
return "";
}
EXPORT struct evm_instance* evm_create(evm_query_fn query_fn,
evm_update_fn update_fn,
evm_call_fn call_fn)
{
struct evm_instance *ret = calloc(1, sizeof(struct evm_instance));
if (ret) {
ret->query_fn = query_fn;
ret->update_fn = update_fn;
ret->call_fn = call_fn;
}
return ret;
}
EXPORT void evm_destroy(struct evm_instance* evm)
{
free(evm);
}
EXPORT bool evm_set_option(struct evm_instance* evm,
char const* name,
char const* value)
{
return false;
}
EXPORT struct evm_result evm_execute(struct evm_instance* instance,
struct evm_env* env,
enum evm_mode mode,
struct evm_hash256 code_hash,
uint8_t const* code,
size_t code_size,
int64_t gas,
uint8_t const* input,
size_t input_size,
struct evm_uint256 value)
{
struct evm_result ret;
memset(&ret, 0, sizeof(struct evm_result));
// Execute code and refer to callbacks: instance->query_fn()
ret.gas_left = 0;
return ret;
}
EXPORT void evm_destroy_result(struct evm_result result)
{
}
EXPORT bool evmjit_is_code_ready(struct evm_instance* instance,
enum evm_mode mode,
struct evm_hash256 code_hash)
{
return true;
}
EXPORT void evmjit_compile(struct evm_instance* instance,
enum evm_mode mode,
uint8_t const* code,
size_t code_size,
struct evm_hash256 code_hash)
{
}

14
include/evm.h
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@ -39,7 +39,7 @@ struct evm_uint256 {
uint64_t words[4];
};
/// 160-bit hash suitable for keeping an Ethereum address.
/// Big-endian 160-bit hash suitable for keeping an Ethereum address.
struct evm_hash160 {
/// The 20 bytes of the hash.
uint8_t bytes[20];
@ -191,7 +191,7 @@ enum evm_update_key {
/// ----------------------| -------------------- | --------------------
/// ::EVM_SSTORE | evm_variant::uint256 | evm_variant::uint256
/// ::EVM_LOG | evm_variant::data | evm_variant::data
/// ::EVM_SELFDESTRUCT | evm_variant::address |
/// ::EVM_SELFDESTRUCT | evm_variant::address | n/a
typedef void (*evm_update_fn)(struct evm_env* env,
enum evm_update_key key,
union evm_variant arg1,
@ -215,14 +215,14 @@ enum evm_call_kind {
/// of CREATE.
/// @param value The value sent to the callee. The endowment in case of
/// CREATE.
/// @param input The call input data or the create init code.
/// @param input The call input data or the CREATE init code.
/// @param input_size The size of the input data.
/// @param output The reference to the memory where the call output is to
/// be copied. In case of create, the memory is guaranteed
/// to be at least 160 bytes to hold the address of the
/// be copied. In case of CREATE, the memory is guaranteed
/// to be at least 20 bytes to hold the address of the
/// created contract.
/// @param output_data The size of the output data. In case of create, expected
/// value is 160.
/// @param output_data The size of the output data. In case of CREATE, expected
/// value is 20.
/// @return If non-negative - the amount of gas left,
/// If negative - an exception occurred during the call/create.
/// There is no need to set 0 address in the output in this case.