Namecoin / AuxPoW: Optimize away hex/binary conversions in parent coi…

…nbase transaction parsing in deserialize_auxpow_header.

lib/auxpow.py

@@ -80,10 +80,9 @@ def deserialize_auxpow_header(base_header, s, expect_trailing_data=False):
 
     # The parent coinbase transaction is first.
     # Deserialize it and save the trailing data.
-    parent_coinbase_tx = Transaction(bh2u(s), expect_trailing_data=True)
-    parent_coinbase_tx_dict, s_hex = fast_tx_deserialize(parent_coinbase_tx)
+    parent_coinbase_tx = Transaction(None, expect_trailing_data=True, raw_bytes=s, expect_trailing_bytes=True)
+    parent_coinbase_tx_dict, s = fast_tx_deserialize(parent_coinbase_tx)
     auxpow_header['parent_coinbase_tx'] = parent_coinbase_tx
-    s = bfh(s_hex)
 
     # Next is the parent block hash.  According to the Bitcoin.it wiki,
     # this field is not actually consensus-critical.  So we don't save it.
@@ -304,7 +303,7 @@ def hex_to_int(s):
 # This is calculated the same as the Transaction.txid() method, but doesn't
 # reserialize it.
 def fast_txid(tx):
-    return bh2u(Hash(bfh(tx.raw))[::-1])
+    return bh2u(Hash(tx.raw_bytes)[::-1])
 
 def fast_tx_deserialize(tx):
     def stub(_bytes, *, net=None):

lib/transaction.py

@@ -560,8 +560,9 @@ def parse_output(vds, i):
     return d
 
 
-def deserialize(raw: str, force_full_parse=False, expect_trailing_data=False) -> dict:
-    raw_bytes = bfh(raw)
+def deserialize(raw: str, force_full_parse=False, expect_trailing_data=False, raw_bytes=None, expect_trailing_bytes=False) -> dict:
+    if raw_bytes is None:
+        raw_bytes = bfh(raw)
     d = {}
     if raw_bytes[:5] == PARTIAL_TXN_HEADER_MAGIC:
         d['partial'] = is_partial = True
@@ -596,6 +597,9 @@ def deserialize(raw: str, force_full_parse=False, expect_trailing_data=False) ->
         raise SerializationError('extra junk at the end')
     if not expect_trailing_data:
         return d
+    # The caller is expecting trailing data to be present; return that trailing data in bytes format
+    if expect_trailing_bytes:
+        return d, raw_bytes[vds.read_cursor:]
     # The caller is expecting trailing data to be present; return that trailing data in hex format
     return d, bh2u(raw_bytes[vds.read_cursor:])
 
@@ -623,13 +627,16 @@ def __str__(self):
             self.raw = self.serialize()
         return self.raw
 
-    def __init__(self, raw, expect_trailing_data=False):
+    def __init__(self, raw, expect_trailing_data=False, raw_bytes=None, expect_trailing_bytes=False):
         if raw is None:
             self.raw = None
+            self.raw_bytes = raw_bytes
         elif isinstance(raw, str):
             self.raw = raw.strip() if raw else None
+            self.raw_bytes = raw_bytes
         elif isinstance(raw, dict):
             self.raw = raw['hex']
+            self.raw_bytes = raw_bytes
         else:
             raise Exception("cannot initialize transaction", raw)
         self._inputs = None
@@ -641,6 +648,7 @@ def __init__(self, raw, expect_trailing_data=False):
         self.is_partial_originally = True
         self._segwit_ser = None  # None means "don't know"
         self.expect_trailing_data = expect_trailing_data
+        self.expect_trailing_bytes = expect_trailing_bytes
 
     def update(self, raw):
         self.raw = raw
@@ -717,23 +725,32 @@ def add_signature_to_txin(cls, txin, signingPos, sig):
         txin['witness'] = None    # force re-serialization
 
     def deserialize(self, force_full_parse=False):
-        if self.raw is None:
+        if self.raw is None and self.raw_bytes is None:
             return
             #self.raw = self.serialize()
         if self._inputs is not None:
             return
         if self.expect_trailing_data:
-            d, trailing_data = deserialize(self.raw, force_full_parse, expect_trailing_data=self.expect_trailing_data)
+            d, trailing_data = deserialize(self.raw, force_full_parse, expect_trailing_data=self.expect_trailing_data, raw_bytes=self.raw_bytes, expect_trailing_bytes=self.expect_trailing_bytes)
         else:
-            d = deserialize(self.raw, force_full_parse)
+            d = deserialize(self.raw, force_full_parse, raw_bytes=self.raw_bytes)
         self._inputs = d['inputs']
         self._outputs = [(x['type'], x['address'], x['value']) for x in d['outputs']]
         self.locktime = d['lockTime']
         self.version = d['version']
         self.is_partial_originally = d['partial']
         self._segwit_ser = d['segwit_ser']
         if self.expect_trailing_data:
-            self.raw = self.raw[:-len(trailing_data)]
+            if self.expect_trailing_bytes:
+                if self.raw is not None:
+                    self.raw = self.raw[:(-2*len(trailing_data))]
+                if self.raw_bytes is not None:
+                    self.raw_bytes = self.raw_bytes[:-len(trailing_data)]
+            else:
+                if self.raw is not None:
+                    self.raw = self.raw[:-len(trailing_data)]
+                if self.raw_bytes is not None:
+                    self.raw_bytes = self.raw_bytes[:(-len(trailing_data)//2)]
             self.expect_trailing_data = False
             return d, trailing_data
         else: