-#######->WARNING<-####### Directory structure changed, see commit message

If you use git-python as a submodule of your own project, which alters the sys.path to import it,
you will have to adjust your code to take the changed directory structure into consideration.

Previously, you would put the path
 ./git-python/lib

into your syspath. All modules moved two levels up, which means that the 'git-python' directory
now is a package itself. This implies that the submodule's path must change so that the root
directory is called 'git'.

Your code must now put the directory containing the submodule into the sys.path.

For example, if you previously would have the following configuration:

 ./ext/git-python/lib/git/__init__.py

you would now change your submodule path to the following:

 ./ext/git

On the latets revision, the directory structure is changed so that
the git/__init__.py file is at the following path:

 ./ext/git/__init__.py

To be able to import git, you need to put ./ext into your sys.path.

1 files changed, 348 insertions, 0 deletions

diff --git a/util.py b/util.py
new file mode 100644
index 00000000..c945e6a3
--- /dev/null
+++ b/util.py
@@ -0,0 +1,348 @@
+# utils.py
+# Copyright (C) 2008, 2009 Michael Trier (mtrier@gmail.com) and contributors
+#
+# This module is part of GitPython and is released under
+# the BSD License: http://www.opensource.org/licenses/bsd-license.php
+
+import os
+import sys
+import time
+import tempfile
+
+from gitdb.util import (
+							make_sha, 
+							LockedFD, 
+							file_contents_ro, 
+							LazyMixin, 
+							to_hex_sha, 
+							to_bin_sha
+						)
+
+__all__ = ( "stream_copy", "join_path", "to_native_path_windows", "to_native_path_linux", 
+			"join_path_native", "Stats", "IndexFileSHA1Writer", "Iterable", "IterableList", 
+			"BlockingLockFile", "LockFile" )
+
+def stream_copy(source, destination, chunk_size=512*1024):
+	"""Copy all data from the source stream into the destination stream in chunks
+	of size chunk_size
+	
+	:return: amount of bytes written"""
+	br = 0
+	while True:
+		chunk = source.read(chunk_size)
+		destination.write(chunk)
+		br += len(chunk)
+		if len(chunk) < chunk_size:
+			break
+	# END reading output stream
+	return br
+
+def join_path(a, *p):
+	"""Join path tokens together similar to os.path.join, but always use 
+	'/' instead of possibly '\' on windows."""
+	path = a
+	for b in p:
+		if b.startswith('/'):
+			path += b[1:]
+		elif path == '' or path.endswith('/'):
+			path +=	 b
+		else:
+			path += '/' + b
+	return path
+	
+def to_native_path_windows(path):
+	return path.replace('/','\\')
+	
+def to_native_path_linux(path):
+	return path.replace('\\','/')
+
+if sys.platform.startswith('win'):
+	to_native_path = to_native_path_windows
+else:
+	# no need for any work on linux
+	def to_native_path_linux(path):
+		return path
+	to_native_path = to_native_path_linux
+
+def join_path_native(a, *p):
+	"""As join path, but makes sure an OS native path is returned. This is only 
+	needed to play it safe on my dear windows and to assure nice paths that only 
+	use '\'"""
+	return to_native_path(join_path(a, *p))
+
+
+class Stats(object):
+	"""
+	Represents stat information as presented by git at the end of a merge. It is 
+	created from the output of a diff operation.
+	
+	``Example``::
+	
+	 c = Commit( sha1 )
+	 s = c.stats
+	 s.total		 # full-stat-dict
+	 s.files		 # dict( filepath : stat-dict )
+	 
+	``stat-dict``
+	
+	A dictionary with the following keys and values::
+	 
+	  deletions = number of deleted lines as int
+	  insertions = number of inserted lines as int
+	  lines = total number of lines changed as int, or deletions + insertions
+	  
+	``full-stat-dict``
+	
+	In addition to the items in the stat-dict, it features additional information::
+	
+	 files = number of changed files as int"""
+	__slots__ = ("total", "files")
+	
+	def __init__(self, total, files):
+		self.total = total
+		self.files = files
+
+	@classmethod
+	def _list_from_string(cls, repo, text):
+		"""Create a Stat object from output retrieved by git-diff.
+		
+		:return: git.Stat"""
+		hsh = {'total': {'insertions': 0, 'deletions': 0, 'lines': 0, 'files': 0}, 'files': dict()}
+		for line in text.splitlines():
+			(raw_insertions, raw_deletions, filename) = line.split("\t")
+			insertions = raw_insertions != '-' and int(raw_insertions) or 0
+			deletions = raw_deletions != '-' and int(raw_deletions) or 0
+			hsh['total']['insertions'] += insertions
+			hsh['total']['deletions'] += deletions
+			hsh['total']['lines'] += insertions + deletions
+			hsh['total']['files'] += 1
+			hsh['files'][filename.strip()] = {'insertions': insertions,
+											  'deletions': deletions,
+											  'lines': insertions + deletions}
+		return Stats(hsh['total'], hsh['files'])
+
+
+class IndexFileSHA1Writer(object):
+	"""Wrapper around a file-like object that remembers the SHA1 of 
+	the data written to it. It will write a sha when the stream is closed
+	or if the asked for explicitly usign write_sha.
+	
+	Only useful to the indexfile
+	
+	:note: Based on the dulwich project"""
+	__slots__ = ("f", "sha1")
+	
+	def __init__(self, f):
+		self.f = f
+		self.sha1 = make_sha("")
+
+	def write(self, data):
+		self.sha1.update(data)
+		return self.f.write(data)
+
+	def write_sha(self):
+		sha = self.sha1.digest()
+		self.f.write(sha)
+		return sha
+
+	def close(self):
+		sha = self.write_sha()
+		self.f.close()
+		return sha
+
+	def tell(self):
+		return self.f.tell()
+
+
+class LockFile(object):
+	"""Provides methods to obtain, check for, and release a file based lock which 
+	should be used to handle concurrent access to the same file.
+	
+	As we are a utility class to be derived from, we only use protected methods.
+	
+	Locks will automatically be released on destruction"""
+	__slots__ = ("_file_path", "_owns_lock")
+	
+	def __init__(self, file_path):
+		self._file_path = file_path
+		self._owns_lock = False
+	
+	def __del__(self):
+		self._release_lock()
+	
+	def _lock_file_path(self):
+		""":return: Path to lockfile"""
+		return "%s.lock" % (self._file_path)
+	
+	def _has_lock(self):
+		""":return: True if we have a lock and if the lockfile still exists
+		:raise AssertionError: if our lock-file does not exist"""
+		if not self._owns_lock:
+			return False
+		
+		return True
+		
+	def _obtain_lock_or_raise(self):
+		"""Create a lock file as flag for other instances, mark our instance as lock-holder
+		
+		:raise IOError: if a lock was already present or a lock file could not be written"""
+		if self._has_lock():
+			return 
+		lock_file = self._lock_file_path()
+		if os.path.isfile(lock_file):
+			raise IOError("Lock for file %r did already exist, delete %r in case the lock is illegal" % (self._file_path, lock_file))
+			
+		try:
+			fd = os.open(lock_file, os.O_WRONLY | os.O_CREAT | os.O_EXCL, 0)
+			os.close(fd)
+		except OSError,e:
+			raise IOError(str(e))
+		
+		self._owns_lock = True
+		
+	def _obtain_lock(self):
+		"""The default implementation will raise if a lock cannot be obtained.
+		Subclasses may override this method to provide a different implementation"""
+		return self._obtain_lock_or_raise()
+		
+	def _release_lock(self):
+		"""Release our lock if we have one"""
+		if not self._has_lock():
+			return
+			
+		# if someone removed our file beforhand, lets just flag this issue
+		# instead of failing, to make it more usable.
+		lfp = self._lock_file_path()
+		try:
+			# on bloody windows, the file needs write permissions to be removable.
+			# Why ... 
+			if os.name == 'nt':
+				os.chmod(lfp, 0777)
+			# END handle win32
+			os.remove(lfp)
+		except OSError:
+			pass
+		self._owns_lock = False
+
+
+class BlockingLockFile(LockFile):
+	"""The lock file will block until a lock could be obtained, or fail after 
+	a specified timeout.
+	
+	:note: If the directory containing the lock was removed, an exception will 
+		be raised during the blocking period, preventing hangs as the lock 
+		can never be obtained."""
+	__slots__ = ("_check_interval", "_max_block_time")
+	def __init__(self, file_path, check_interval_s=0.3, max_block_time_s=sys.maxint):
+		"""Configure the instance
+		
+		:parm check_interval_s:
+			Period of time to sleep until the lock is checked the next time.
+			By default, it waits a nearly unlimited time
+		
+		:parm max_block_time_s: Maximum amount of seconds we may lock"""
+		super(BlockingLockFile, self).__init__(file_path)
+		self._check_interval = check_interval_s
+		self._max_block_time = max_block_time_s
+		
+	def _obtain_lock(self):
+		"""This method blocks until it obtained the lock, or raises IOError if 
+		it ran out of time or if the parent directory was not available anymore.
+		If this method returns, you are guranteed to own the lock"""
+		starttime = time.time()
+		maxtime = starttime + float(self._max_block_time)
+		while True:
+			try:
+				super(BlockingLockFile, self)._obtain_lock()
+			except IOError:
+				# synity check: if the directory leading to the lockfile is not
+				# readable anymore, raise an execption
+				curtime = time.time()
+				if not os.path.isdir(os.path.dirname(self._lock_file_path())):
+					msg = "Directory containing the lockfile %r was not readable anymore after waiting %g seconds" % (self._lock_file_path(), curtime - starttime)
+					raise IOError(msg)
+				# END handle missing directory
+				
+				if curtime >= maxtime:
+					msg = "Waited %g seconds for lock at %r" % ( maxtime - starttime, self._lock_file_path())
+					raise IOError(msg)
+				# END abort if we wait too long
+				time.sleep(self._check_interval)
+			else:
+				break
+		# END endless loop
+	
+
+class IterableList(list):
+	"""
+	List of iterable objects allowing to query an object by id or by named index::
+	 
+	 heads = repo.heads
+	 heads.master
+	 heads['master']
+	 heads[0]
+	 
+	It requires an id_attribute name to be set which will be queried from its 
+	contained items to have a means for comparison.
+	
+	A prefix can be specified which is to be used in case the id returned by the 
+	items always contains a prefix that does not matter to the user, so it 
+	can be left out."""
+	__slots__ = ('_id_attr', '_prefix')
+	
+	def __new__(cls, id_attr, prefix=''):
+		return super(IterableList,cls).__new__(cls)
+		
+	def __init__(self, id_attr, prefix=''):
+		self._id_attr = id_attr
+		self._prefix = prefix
+		if not isinstance(id_attr, basestring):
+			raise ValueError("First parameter must be a string identifying the name-property. Extend the list after initialization")
+		# END help debugging !
+		
+	def __getattr__(self, attr):
+		attr = self._prefix + attr
+		for item in self:
+			if getattr(item, self._id_attr) == attr:
+				return item
+		# END for each item
+		return list.__getattribute__(self, attr)
+		
+	def __getitem__(self, index):
+		if isinstance(index, int):
+			return list.__getitem__(self,index)
+		
+		try:
+			return getattr(self, index)
+		except AttributeError:
+			raise IndexError( "No item found with id %r" % (self._prefix + index) )
+			
+
+class Iterable(object):
+	"""Defines an interface for iterable items which is to assure a uniform 
+	way to retrieve and iterate items within the git repository"""
+	__slots__ = tuple()
+	_id_attribute_ = "attribute that most suitably identifies your instance"
+	
+	@classmethod
+	def list_items(cls, repo, *args, **kwargs):
+		"""
+		Find all items of this type - subclasses can specify args and kwargs differently.
+		If no args are given, subclasses are obliged to return all items if no additional 
+		arguments arg given.
+		
+		:note: Favor the iter_items method as it will
+		
+		:return:list(Item,...) list of item instances"""
+		out_list = IterableList( cls._id_attribute_ )
+		out_list.extend(cls.iter_items(repo, *args, **kwargs))
+		return out_list
+		
+		
+	@classmethod
+	def iter_items(cls, repo, *args, **kwargs):
+		"""For more information about the arguments, see list_items
+		:return:  iterator yielding Items"""
+		raise NotImplementedError("To be implemented by Subclass")
+		
+