1 files changed, 173 insertions, 0 deletions
diff --git a/index/typ.py b/index/typ.py
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index 00000000..ad988285
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+++ b/index/typ.py
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+"""Module with additional types used by the index"""
+
+from util import (
+					pack, 
+					unpack
+				)
+
+from binascii import (
+						b2a_hex,
+					)
+
+from git.objects import Blob
+__all__ = ('BlobFilter', 'BaseIndexEntry', 'IndexEntry')
+
+#{ Invariants
+CE_NAMEMASK = 0x0fff
+CE_STAGEMASK = 0x3000
+CE_EXTENDED = 0x4000
+CE_VALID = 0x8000
+CE_STAGESHIFT = 12
+
+#} END invariants
+
+class BlobFilter(object):
+	"""
+	Predicate to be used by iter_blobs allowing to filter only return blobs which
+	match the given list of directories or files.
+
+	The given paths are given relative to the repository.
+	"""
+	__slots__ = 'paths'
+
+	def __init__(self, paths):
+		""":param paths:
+			tuple or list of paths which are either pointing to directories or
+			to files relative to the current repository
+		"""
+		self.paths = paths
+
+	def __call__(self, stage_blob):
+		path = stage_blob[1].path
+		for p in self.paths:
+			if path.startswith(p):
+				return True
+		# END for each path in filter paths
+		return False
+
+
+class BaseIndexEntry(tuple):
+	"""Small Brother of an index entry which can be created to describe changes
+	done to the index in which case plenty of additional information is not requried.
+
+	As the first 4 data members match exactly to the IndexEntry type, methods
+	expecting a BaseIndexEntry can also handle full IndexEntries even if they
+	use numeric indices for performance reasons. """
+
+	def __str__(self):
+		return "%o %s %i\t%s" % (self.mode, self.hexsha, self.stage, self.path)
+		
+	def __repr__(self):
+		return "(%o, %s, %i, %s)" % (self.mode, self.hexsha, self.stage, self.path)
+
+	@property
+	def mode(self):
+		""" File Mode, compatible to stat module constants """
+		return self[0]
+
+	@property
+	def binsha(self):
+		"""binary sha of the blob """
+		return self[1]
+		
+	@property
+	def hexsha(self):
+		"""hex version of our sha"""
+		return b2a_hex(self[1])
+
+	@property
+	def stage(self):
+		"""Stage of the entry, either:
+		
+			* 0 = default stage
+			* 1 = stage before a merge or common ancestor entry in case of a 3 way merge
+			* 2 = stage of entries from the 'left' side of the merge
+			* 3 = stage of entries from the right side of the merge
+		
+		:note: For more information, see http://www.kernel.org/pub/software/scm/git/docs/git-read-tree.html
+		"""
+		return (self[2] & CE_STAGEMASK) >> CE_STAGESHIFT
+
+	@property
+	def path(self):
+		""":return: our path relative to the repository working tree root"""
+		return self[3]
+
+	@property
+	def flags(self):
+		""":return: flags stored with this entry"""
+		return self[2]
+
+	@classmethod
+	def from_blob(cls, blob, stage = 0):
+		""":return: Fully equipped BaseIndexEntry at the given stage"""
+		return cls((blob.mode, blob.binsha, stage << CE_STAGESHIFT, blob.path))
+		
+	def to_blob(self, repo):
+		""":return: Blob using the information of this index entry"""
+		return Blob(repo, self.binsha, self.mode, self.path) 
+
+
+class IndexEntry(BaseIndexEntry):
+	"""Allows convenient access to IndexEntry data without completely unpacking it.
+
+	Attributes usully accessed often are cached in the tuple whereas others are
+	unpacked on demand.
+
+	See the properties for a mapping between names and tuple indices. """
+	@property
+	def ctime(self):
+		"""
+		:return:
+			Tuple(int_time_seconds_since_epoch, int_nano_seconds) of the
+			file's creation time"""
+		return unpack(">LL", self[4])
+
+	@property
+	def mtime(self):
+		"""See ctime property, but returns modification time """
+		return unpack(">LL", self[5])
+
+	@property
+	def dev(self):
+		""" Device ID """
+		return self[6]
+
+	@property
+	def inode(self):
+		""" Inode ID """
+		return self[7]
+
+	@property
+	def uid(self):
+		""" User ID """
+		return self[8]
+
+	@property
+	def gid(self):
+		""" Group ID """
+		return self[9]
+
+	@property
+	def size(self):
+		""":return: Uncompressed size of the blob """
+		return self[10]
+		
+	@classmethod
+	def from_base(cls, base):
+		""" 
+		:return:
+			Minimal entry as created from the given BaseIndexEntry instance.
+			Missing values will be set to null-like values
+
+		:param base: Instance of type BaseIndexEntry"""
+		time = pack(">LL", 0, 0)
+		return IndexEntry((base.mode, base.binsha, base.flags, base.path, time, time, 0, 0, 0, 0, 0))
+
+	@classmethod
+	def from_blob(cls, blob, stage = 0):
+		""":return: Minimal entry resembling the given blob object"""
+		time = pack(">LL", 0, 0)
+		return IndexEntry((blob.mode, blob.binsha, stage << CE_STAGESHIFT, blob.path, time, time, 0, 0, 0, 0, blob.size))
+
+