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# objects.py -- Acces to base git objects
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# Copyright (C) 2007 James Westby <jw+debian@jameswestby.net>
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# The header parsing code is based on that from git itself, which is
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# Copyright (C) 2005 Linus Torvalds
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# and licensed under v2 of the GPL.
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# This program is free software; you can redistribute it and/or
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# modify it under the terms of the GNU General Public License
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# as published by the Free Software Foundation; version 2
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU General Public License for more details.
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
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committer_id = "committer"
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def _decompress(string):
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dcomp = zlib.decompressobj()
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dcomped = dcomp.decompress(string)
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dcomped += dcomp.flush()
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"""Takes a string and returns the hex of the sha within"""
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hexsha += "0%x" % ord(c)
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hexsha += "%x" % ord(c)
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assert len(hexsha) == 40, "Incorrect length of sha1 string: %d" % \
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class ShaFile(object):
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def _update_contents(self):
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"""Update the _contents from the _text"""
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self._contents = [ord(c) for c in self._text]
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def _parse_legacy_object(cls, map):
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"""Parse a legacy object, creating it and setting object._text"""
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text = _decompress(map)
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for posstype in type_map.keys():
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if text.startswith(posstype):
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object = type_map[posstype]()
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text = text[len(posstype):]
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assert object is not None, "%s is not a known object type" % text[:9]
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assert text[0] == ' ', "%s is not a space" % text[0]
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while text[0] >= '0' and text[0] <= '9':
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if i > 0 and size == 0:
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assert False, "Size is not in canonical format"
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size = (size * 10) + int(text[0])
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assert text[0] == "\0", "Size not followed by null"
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object._update_contents()
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def _parse_object(cls, map):
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"""Parse a new style object , creating it and setting object._text"""
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num_type = (byte >> 4) & 7
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object = num_type_map[num_type]()
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assert False, "Not a known type: %d" % num_type
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while((byte & 0x80) != 0):
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object._text = _decompress(raw)
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object._update_contents()
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def _parse_file(cls, map):
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word = (ord(map[0]) << 8) + ord(map[1])
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if ord(map[0]) == 0x78 and (word % 31) == 0:
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return cls._parse_legacy_object(map)
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return cls._parse_object(map)
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"""Don't call this directly"""
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def _parse_text(self):
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"""For subclasses to do initialistion time parsing"""
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def from_file(cls, filename):
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"""Get the contents of a SHA file on disk"""
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size = os.path.getsize(filename)
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f = open(filename, 'rb+')
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map = mmap.mmap(f.fileno(), size)
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shafile = cls._parse_file(map)
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shafile._parse_text()
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return "%s %lu\0" % (self._type, len(self._contents))
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"""The raw bytes of this object"""
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return self._contents
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"""The SHA1 object that is the name of this object."""
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ressha.update(self._header())
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ressha.update(self._text)
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"""A Git Blob object."""
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"""The text contained within the blob object."""
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def from_file(cls, filename):
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blob = ShaFile.from_file(filename)
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assert blob._type == cls._type, "%s is not a blob object" % filename
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def from_string(cls, string):
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"""Create a blob from a string."""
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shafile._text = string
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shafile._update_contents()
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"""A Git tree object"""
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def from_file(cls, filename):
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tree = ShaFile.from_file(filename)
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assert tree._type == cls._type, "%s is not a tree object" % filename
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"""Reutrn a list of tuples describing the tree entries"""
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def _parse_text(self):
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"""Grab the entries in the tree"""
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while count < len(self._text):
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chr = self._text[count]
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assert chr >= '0' and chr <= '7', "%s is not a valid mode char" % chr
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mode = (mode << 3) + (ord(chr) - ord('0'))
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chr = self._text[count]
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chr = self._text[count]
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chr = self._text[count]
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chr = self._text[count]
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sha = self._text[count:count+20]
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hexsha = sha_to_hex(sha)
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self._entries.append((mode, name, hexsha))
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class Commit(ShaFile):
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"""A git commit object"""
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def from_file(cls, filename):
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commit = ShaFile.from_file(filename)
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assert commit._type == cls._type, "%s is not a commit object" % filename
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def _parse_text(self):
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assert text.startswith(tree_id), "Invlid commit object, " \
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"must start with %s" % tree_id
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count += len(tree_id)
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assert text[count] == ' ', "Invalid commit object, " \
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"%s must be followed by space not %s" % (tree_id, text[count])
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self._tree = text[count:count+40]
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assert text[count] == "\n", "Invalid commit object, " \
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"tree sha must be followed by newline"
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while text[count:].startswith(parent_id):
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count += len(parent_id)
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assert text[count] == ' ', "Invalid commit object, " \
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"%s must be followed by space not %s" % (parent_id, text[count])
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self._parents.append(text[count:count+40])
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assert text[count] == "\n", "Invalid commit object, " \
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"parent sha must be followed by newline"
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if text[count:].startswith(author_id):
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count += len(author_id)
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assert text[count] == ' ', "Invalid commit object, " \
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"%s must be followed by space not %s" % (author_id, text[count])
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while text[count] != '\n':
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self._author += text[count]
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self._committer = None
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if text[count:].startswith(committer_id):
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count += len(committer_id)
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assert text[count] == ' ', "Invalid commit object, " \
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"%s must be followed by space not %s" % (committer_id, text[count])
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while text[count] != '\n':
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self._committer += text[count]
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assert text[count] == '\n', "There must be a new line after the headers"
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self._message = text[count:]
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"""Returns the tree that is the state of this commit"""
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"""Return a list of parents of this commit."""
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"""Returns the name of the author of the commit"""
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"""Returns the name of the committer of the commit"""
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return self._committer
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"""Returns the commit message"""
added
removed
git/objects.py
