Proposed homestead changes v0.1

Author: vub

ethereum/blocks.py

@@ -39,7 +39,10 @@
 def calc_difficulty(parent, timestamp):
     config = parent.config
     offset = parent.difficulty // config['BLOCK_DIFF_FACTOR']
-    sign = 1 if timestamp - parent.timestamp < config['DIFF_ADJUSTMENT_CUTOFF'] else -1
+    if parent.number < config['HOMESTEAD_FORK_BLKNUM']:
+        sign = 1 if timestamp - parent.timestamp < config['DIFF_ADJUSTMENT_CUTOFF'] else -1
+    else:
+        sign = max(1 - 2 * ((timestamp - parent.timestamp) // config['HOMESTEAD_DIFF_ADJUSTMENT_CUTOFF']), -99)
     # If we enter a special mode where the genesis difficulty starts off below
     # the minimal difficulty, we allow low-difficulty blocks (this will never
     # happen in the official protocol)

ethereum/config.py

@@ -43,6 +43,9 @@
     EXPDIFF_FREE_PERIODS=2,
     # Blank account initial nonce
     ACCOUNT_INITIAL_NONCE=0,
+    # Homestead fork (500k on livenet?)
+    HOMESTEAD_FORK_BLKNUM=2**100,
+    HOMESTEAD_DIFF_ADJUSTMENT_CUTOFF=16,
 )
 assert default_config['NEPHEW_REWARD'] == \
     default_config['BLOCK_REWARD'] // 32

ethereum/processblock.py

@@ -124,10 +124,18 @@ def apply_transaction(block, tx):
     block.increment_nonce(tx.sender)
     # print block.get_nonce(tx.sender), '@@@'
 
+    intrinsic_gas = intrinsic_gas_used(tx)
+    if block.number >= block.config['HOMESTEAD_FORK_BLKNUM']:
+        assert tx.s * 2 < transactions.secpk1n
+        if not tx.to or tx.to == CREATE_CONTRACT_ADDRESS:
+            intrinsic_gas += opcodes.CREATE[3]
+            if tx.startgas < intrinsic_gas:
+                raise InsufficientStartGas(rp('startgas', tx.startgas, intrinsic_gas))
+                
     # buy startgas
     assert block.get_balance(tx.sender) >= tx.startgas * tx.gasprice
     block.delta_balance(tx.sender, -tx.startgas * tx.gasprice)
-    message_gas = tx.startgas - intrinsic_gas_used(tx)
+    message_gas = tx.startgas - intrinsic_gas
     message_data = vm.CallData([safe_ord(x) for x in tx.data], 0, len(tx.data))
     message = vm.Message(tx.sender, tx.to, tx.value, message_gas, message_data, code_address=tx.to)
 
@@ -293,6 +301,8 @@ def create_contract(ext, msg):
         else:
             dat = []
             #print('CONTRACT CREATION OOG', 'have', gas, 'want', gcost)
+            if ext._block.number >= ext._block.config['HOMESTEAD_FORK_BLKNUM']:
+                return 0, 0, b''
             log_msg.debug('CONTRACT CREATION OOG', have=gas, want=gcost)
         ext._block.set_code(msg.to, b''.join(map(ascii_chr, dat)))
         return 1, gas, msg.to

ethereum/transactions.py

@@ -53,10 +53,7 @@ class Transaction(rlp.Serializable):
     _sender = None
 
     def __init__(self, nonce, gasprice, startgas, to, value, data, v=0, r=0, s=0):
-        if len(to) in (40, 48):
-            to = decode_hex(to)
-        if len(to) == 24:
-            to = utils.check_and_strip_checksum(to)
+        to = utils.normalize_address(to, allow_blank=True)
         assert len(to) == 20 or len(to) == 0
         super(Transaction, self).__init__(nonce, gasprice, startgas, to, value, data, v, r, s)
         self.logs = []