Sha1 verification works as well, forgot to fill in the base buffer for delta-application, and fixed the broken DeltaApplyReader's seek method

Author: Byron

fun.py

@@ -200,7 +200,7 @@ def apply_delta_data(src_buf, src_buf_size, delta_buf, delta_buf_size, target_fi
 			if (cp_off + cp_size < cp_size or
 			    cp_off + cp_size > src_buf_size):
 				break
-			twrite(src_buf[cp_off:cp_off+cp_size])
+			twrite(buffer(src_buf, cp_off, cp_size))
 		elif c:
 			twrite(db[i:i+c])
 			i += c

pack.py

@@ -611,6 +611,7 @@ def is_valid_stream(self, sha, use_crc=False):
 			# write a loose object, which is the basis for the sha
 			write_object(stream.type, stream.size, stream.read, shawriter.write)
 
+			assert shawriter.sha(as_hex=False) == sha
 			return shawriter.sha(as_hex=False) == sha
 		# END handle crc/sha verification
 		return True

stream.py

@@ -358,6 +358,7 @@ def _set_cache_(self, attr):
 		# Allocate private memory map big enough to hold the first base buffer
 		# We need random access to it
 		bbuf = allocate_memory(base_size)
+		stream_copy(self._bstream.read, bbuf.write, base_size, 256*mmap.PAGESIZE)
 
 		# allocate memory map large enough for the largest (intermediate) target
 		# We will use it as scratch space for all delta ops. If the final 
@@ -408,6 +409,8 @@ def read(self, count=0):
 		bl = self._size - self._br		# bytes left
 		if count < 1 or count > bl:
 			count = bl
+		# NOTE: we could check for certain size limits, and possibly
+		# return buffers instead of strings to prevent byte copying
 		data = self._mm_target.read(count)
 		self._br += len(data)
 		return data
@@ -418,7 +421,8 @@ def seek(self, offset, whence=os.SEEK_SET):
 		if offset != 0 or whence != os.SEEK_SET:
 			raise ValueError("Can only seek to position 0")
 		# END handle offset
-		self._size
+		self._br = 0
+		self._mm_target.seek(0)
 
 	#{ Interface 
 

test/test_pack.py

@@ -90,7 +90,13 @@ def _assert_pack_file(self, pack, version, size):
 			# END get deltastream
 
 			# read all
-			assert len(dstream.read()) == dstream.size 
+			data = dstream.read()
+			assert len(data) == dstream.size
+			
+			# test seek
+			dstream.seek(0)
+			assert dstream.read() == data
+			
 
 			# read chunks
 			# NOTE: the current implementation is safe, it basically transfers
@@ -119,7 +125,6 @@ def test_pack_entity(self):
 										(self.packfile_v2_2, self.packindexfile_v2)):
 			packfile, version, size = packinfo
 			indexfile, version, size = indexinfo
-			print packfile
 			entity = PackEntity(packfile)
 			assert entity.pack().path() == packfile
 			assert entity.index().path() == indexfile
@@ -136,7 +141,6 @@ def test_pack_entity(self):
 				assert not info.type_id in delta_types
 
 				# verify the stream
-				print info
 				try:
 					assert entity.is_valid_stream(info.sha, use_crc=True)
 				except UnsupportedOperation: