Merge pull request #45 from poanetwork/log_operations

log operations

.dialyzer.ignore-warnings

@@ -44,6 +44,7 @@ lib/evm/interface/mock/mock_account_interface.ex:138: The inferred return type o
 lib/evm/interface/mock/mock_account_interface.ex:199: The return type {integer(),atom(),#{'__struct__':='Elixir.EVM.SubState', 'logs':=binary(), 'refund':=integer(), 'suicide_list':=[<<_:160>>]}} in the specification of create_contract/9 is not a subtype of {atom(),integer(),#{'__struct__':='Elixir.EVM.SubState', 'logs':=binary(), 'refund':=integer(), 'suicide_list':=[<<_:160>>]}}, which is the expected return type for the callback of the 'Elixir.EVM.Interface.AccountInterface' behaviour
 lib/evm/interface/mock/mock_account_interface.ex:199: Invalid type specification for function 'Elixir.EVM.Interface.AccountInterface.EVM.Interface.Mock.MockAccountInterface':create_contract/9. The success typing is (atom() | #{'contract_result':='nil' | [{atom(),_}] | map(), _=>_},_,_,_,_,_,_,_,_) -> {atom() | #{'contract_result':='nil' | [{_,_}] | map(), _=>_},_,_}
 lib/evm/interface/mock/mock_block_interface.ex:10: Invalid type specification for function 'Elixir.EVM.Interface.Mock.MockBlockInterface':new/2. The success typing is (_,_) -> #{'__struct__':='Elixir.EVM.Interface.Mock.MockBlockInterface', 'block_header':=_, 'block_map':=_}
+lib/evm/interface/mock/mock_account_interface.ex:199: The return type {integer(),atom(),#{'__struct__':='Elixir.EVM.SubState', 'logs':=[#{'__struct__':='Elixir.EVM.LogEntry', 'address':=<<_:160>>, 'data':=binary(), 'topics':=[binary()]}], 'refund':=integer(), 'suicide_list':=[<<_:160>>]}} in the specification of create_contract/9 is not a subtype of {atom(),integer(),#{'__struct__':='Elixir.EVM.SubState', 'logs':=[#{'__struct__':='Elixir.EVM.LogEntry', 'address':=<<_:160>>, 'data':=binary(), 'topics':=[binary()]}], 'refund':=integer(), 'suicide_list':=[<<_:160>>]}}, which is the expected return type for the callback of the 'Elixir.EVM.Interface.AccountInterface' behaviour
 
 lib/evm/machine_code.ex:113: The variable _@1 can never match since previous clauses completely covered the type bitstring()
 lib/evm/machine_code.ex:113: Cons will produce an improper list since its 2nd argument is binary(

lib/evm.ex

@@ -6,17 +6,17 @@ defmodule EVM do
   # σ[a]
   @type account :: %{
           # σ[a]n
-          :nonce => integer(),
+          nonce: integer(),
           # σ[a]b
-          :balance => integer(),
+          balance: integer(),
           # σ[a]s
-          :storage => MerklePatriciaTree.Trie.t(),
+          storage: MerklePatriciaTree.Trie.t(),
           # σ[a]c
-          :code => binary()
+          code: binary()
         }
   # σ
   @type world_state :: %{
-          binary() => account()
+          address() => account()
         }
   @type trie_root :: MerklePatriciaTree.Trie.root_hash()
   @type val :: integer()

lib/evm/gas.ex

@@ -107,7 +107,7 @@ defmodule EVM.Gas do
   @push_instrs Enum.map(0..32, fn n -> :"push#{n}" end)
   @dup_instrs Enum.map(0..16, fn n -> :"dup#{n}" end)
   @swap_instrs Enum.map(0..16, fn n -> :"swap#{n}" end)
-  @log_instrs Enum.map(1..4, fn n -> :"log#{n}" end)
+  @log_instrs Enum.map(0..4, fn n -> :"log#{n}" end)
   @w_very_low_instr [
                       :add,
                       :sub,
@@ -390,6 +390,26 @@ defmodule EVM.Gas do
     @g_call + call_value_cost(value) + gas_limit
   end
 
+  def operation_cost(:log0, [_offset, size | _], _machine_state, _exec_end) do
+    @g_log + @g_logdata * size
+  end
+
+  def operation_cost(:log1, [_offset, size | _], _machine_state, _exec_end) do
+    @g_log + @g_logdata * size + @g_logtopic
+  end
+
+  def operation_cost(:log2, [_offset, size | _], _machine_state, _exec_end) do
+    @g_log + @g_logdata * size + @g_logtopic * 2
+  end
+
+  def operation_cost(:log3, [_offset, size | _], _machine_state, _exec_end) do
+    @g_log + @g_logdata * size + @g_logtopic * 3
+  end
+
+  def operation_cost(:log4, [_offset, size | _], _machine_state, _exec_end) do
+    @g_log + @g_logdata * size + @g_logtopic * 4
+  end
+
   def operation_cost(operation, _inputs, _machine_state, _exec_env) do
     cond do
       operation in @w_very_low_instr -> @g_verylow
@@ -405,7 +425,6 @@ defmodule EVM.Gas do
       operation == :balance -> @g_balance
       operation == :sload -> @g_sload
       operation == :jumpdest -> @g_jumpdest
-      operation in @log_instrs -> 0
       true -> 0
     end
   end

lib/evm/log_entry.ex

@@ -0,0 +1,100 @@
+defmodule EVM.LogEntry do
+  @moduledoc """
+  This module contains functions to work with logs.
+  """
+
+  alias EVM.{Address, Helpers}
+
+  defstruct address: nil, topics: [], data: nil
+
+  @type t :: %__MODULE__{
+          address: EVM.address(),
+          topics: [binary()],
+          data: binary()
+        }
+
+  @doc """
+  Creates new log entry.
+
+  ## Examples
+
+      iex> EVM.LogEntry.new(0, [0, 0, 0, 0], <<1>>)
+      %EVM.LogEntry{
+        address: <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0>>,
+        data: <<1>>,
+        topics: [0, 0, 0, 0]
+      }
+
+      iex> EVM.LogEntry.new( <<15, 87, 46, 82, 149, 197, 127, 21, 136, 111, 155, 38, 62, 47, 109, 45, 108, 123, 94, 198>>, [0, 0, 0, 0], <<1>>)
+      %EVM.LogEntry{
+        address: <<15, 87, 46, 82, 149, 197, 127, 21, 136, 111, 155, 38, 62, 47, 109,
+          45, 108, 123, 94, 198>>,
+        data: <<1>>,
+        topics: [0, 0, 0, 0]
+      }
+  """
+  @spec new(integer() | binary(), [integer()], binary()) :: t()
+  def new(address, topics, data) do
+    address = if is_number(address), do: address |> Address.new(), else: address
+
+    %__MODULE__{
+      address: address,
+      topics: topics,
+      data: data
+    }
+  end
+
+  @doc """
+  Converts log struct to standard Ethereum list representation.
+
+  ## Examples
+
+      iex> log = %EVM.LogEntry{
+      ...> address: <<15, 87, 46, 82, 149, 197, 127, 21, 136, 111, 155, 38, 62, 47, 109,
+      ...>       45, 108, 123, 94, 198>>,
+      ...> data: <<255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      ...>       255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+      ...>       255, 255, 255>>,
+      ...> topics: [0, 0, 0]
+      ...> }
+      iex> log |> EVM.LogEntry.to_list
+      [
+        <<15, 87, 46, 82, 149, 197, 127, 21, 136, 111, 155, 38, 62, 47, 109, 45, 108,
+          123, 94, 198>>,
+        [
+          <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0, 0, 0>>,
+          <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0, 0, 0>>,
+          <<0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0, 0, 0>>
+        ],
+        <<255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+          255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
+          255, 255>>
+      ]
+
+  """
+  @spec to_list(t()) :: [binary()]
+  def to_list(log) do
+    topics =
+      log.topics
+      |> Enum.map(fn topic ->
+        topic |> Helpers.left_pad_bytes()
+      end)
+
+    [log.address, topics, log.data]
+  end
+end
+
+defimpl ExRLP.Encode, for: EVM.LogEntry do
+  alias ExRLP.Encode
+  alias EVM.LogEntry
+
+  @spec encode(LogEntry.t(), keyword()) :: binary()
+  def encode(log, options \\ []) do
+    log
+    |> LogEntry.to_list()
+    |> Encode.encode(options)
+  end
+end

lib/evm/operation.ex

@@ -220,10 +220,6 @@ defmodule EVM.Operation do
       # nil
       iex> EVM.Operation.run_operation(EVM.Operation.metadata(:stop), %EVM.MachineState{stack: [1, 2]}, %EVM.SubState{}, %EVM.ExecEnv{})
       {%EVM.MachineState{stack: [1, 2]}, %EVM.SubState{}, %EVM.ExecEnv{}}
-
-      # Unimplemented
-      iex> EVM.Operation.run_operation(EVM.Operation.metadata(:log0), %EVM.MachineState{stack: [1, 2]}, %EVM.SubState{}, %EVM.ExecEnv{})
-      {%EVM.MachineState{stack: []}, %EVM.SubState{}, %EVM.ExecEnv{}}
   """
   @spec run_operation(EVM.Operation.Metadata.t(), MachineState.t(), SubState.t(), ExecEnv.t()) ::
           {MachineState.t(), SubState.t(), ExecEnv.t()}
@@ -316,9 +312,6 @@ defmodule EVM.Operation do
       iex> EVM.Operation.merge_state(:noop, EVM.Operation.metadata(:add), %EVM.MachineState{}, %EVM.SubState{}, %EVM.ExecEnv{})
       {%EVM.MachineState{}, %EVM.SubState{}, %EVM.ExecEnv{}}
 
-      iex> EVM.Operation.merge_state(:unimplemented, EVM.Operation.metadata(:blarg), %EVM.MachineState{}, %EVM.SubState{}, %EVM.ExecEnv{})
-      {%EVM.MachineState{}, %EVM.SubState{}, %EVM.ExecEnv{}}
-
       iex> EVM.Operation.merge_state(%{stack: [1, 2, 3]}, :add, %EVM.MachineState{}, %EVM.SubState{}, %EVM.ExecEnv{})
       {%EVM.MachineState{stack: [1, 2, 3]}, %EVM.SubState{}, %EVM.ExecEnv{}}
 
@@ -348,12 +341,6 @@ defmodule EVM.Operation do
     {machine_state, sub_state, exec_env}
   end
 
-  def merge_state(:unimplemented, operation, machine_state, sub_state, exec_env) do
-    Logger.debug("Executing (and ignoring) unimplemented operation: #{operation}")
-
-    {machine_state, sub_state, exec_env}
-  end
-
   def merge_state(
         updated_machine_state = %EVM.MachineState{},
         _operation,