[stgit] / stgit / gitmergeonefile.py

"""Performs a 3-way merge for GIT files
"""

__copyright__ = """
Copyright (C) 2006, Catalin Marinas <catalin.marinas@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2 as
published by the Free Software Foundation.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
"""

import sys, os
from stgit import basedir
from stgit.config import config, file_extensions
from stgit.utils import append_string


class GitMergeException(Exception):
    pass


#
# Options
#
try:
    merger = config.get('stgit', 'merger')
    keeporig = config.get('stgit', 'keeporig')
except Exception, err:
    raise GitMergeException, 'Configuration error: %s' % err


#
# Utility functions
#
def __str2none(x):
    if x == '':
        return None
    else:
        return x

def __output(cmd):
    f = os.popen(cmd, 'r')
    string = f.readline().rstrip()
    if f.close():
        raise GitMergeException, 'Error: failed to execute "%s"' % cmd
    return string

def __checkout_files(orig_hash, file1_hash, file2_hash,
                     path,
                     orig_mode, file1_mode, file2_mode):
    """Check out the files passed as arguments
    """
    global orig, src1, src2

    extensions = file_extensions()

    if orig_hash:
        orig = path + extensions['ancestor']
        tmp = __output('git-unpack-file %s' % orig_hash)
        os.chmod(tmp, int(orig_mode, 8))
        os.renames(tmp, orig)
    if file1_hash:
        src1 = path + extensions['current']
        tmp = __output('git-unpack-file %s' % file1_hash)
        os.chmod(tmp, int(file1_mode, 8))
        os.renames(tmp, src1)
    if file2_hash:
        src2 = path + extensions['patched']
        tmp = __output('git-unpack-file %s' % file2_hash)
        os.chmod(tmp, int(file2_mode, 8))
        os.renames(tmp, src2)

def __remove_files(orig_hash, file1_hash, file2_hash):
    """Remove any temporary files
    """
    if orig_hash:
        os.remove(orig)
    if file1_hash:
        os.remove(src1)
    if file2_hash:
        os.remove(src2)
    pass

def __conflict(path):
    """Write the conflict file for the 'path' variable and exit
    """
    append_string(os.path.join(basedir.get(), 'conflicts'), path)


#
# Main algorithm
#
def merge(orig_hash, file1_hash, file2_hash,
          path,
          orig_mode, file1_mode, file2_mode):
    """Three-way merge for one file algorithm
    """
    __checkout_files(orig_hash, file1_hash, file2_hash,
                     path,
                     orig_mode, file1_mode, file2_mode)

    # file exists in origin
    if orig_hash:
        # modified in both
        if file1_hash and file2_hash:
            # if modes are the same (git-read-tree probably dealt with it)
            if file1_hash == file2_hash:
                if os.system('git-update-index --cacheinfo %s %s %s'
                             % (file1_mode, file1_hash, path)) != 0:
                    print >> sys.stderr, 'Error: git-update-index failed'
                    __conflict(path)
                    return 1
                if os.system('git-checkout-index -u -f -- %s' % path):
                    print >> sys.stderr, 'Error: git-checkout-index failed'
                    __conflict(path)
                    return 1
                if file1_mode != file2_mode:
                    print >> sys.stderr, \
                          'Error: File added in both, permissions conflict'
                    __conflict(path)
                    return 1
            # 3-way merge
            else:
                merge_ok = os.system(merger % {'branch1': src1,
                                               'ancestor': orig,
                                               'branch2': src2,
                                               'output': path }) == 0

                if merge_ok:
                    os.system('git-update-index -- %s' % path)
                    __remove_files(orig_hash, file1_hash, file2_hash)
                    return 0
                else:
                    print >> sys.stderr, \
                          'Error: three-way merge tool failed for file "%s"' \
                          % path
                    # reset the cache to the first branch
                    os.system('git-update-index --cacheinfo %s %s %s'
                              % (file1_mode, file1_hash, path))
                    if keeporig != 'yes':
                        __remove_files(orig_hash, file1_hash, file2_hash)
                    __conflict(path)
                    return 1
        # file deleted in both or deleted in one and unchanged in the other
        elif not (file1_hash or file2_hash) \
               or file1_hash == orig_hash or file2_hash == orig_hash:
            if os.path.exists(path):
                os.remove(path)
            __remove_files(orig_hash, file1_hash, file2_hash)
            return os.system('git-update-index --remove -- %s' % path)
        # file deleted in one and changed in the other
        else:
            # Do something here - we must at least merge the entry in
            # the cache, instead of leaving it in U(nmerged) state. In
            # fact, stg resolved does not handle that.

            # Do the same thing cogito does - remove the file in any case.
            os.system('git-update-index --remove -- %s' % path)

            #if file1_hash:
                ## file deleted upstream and changed in the patch. The
                ## patch is probably going to move the changes
                ## elsewhere.

                #os.system('git-update-index --remove -- %s' % path)
            #else:
                ## file deleted in the patch and changed upstream. We
                ## could re-delete it, but for now leave it there -
                ## and let the user check if he still wants to remove
                ## the file.

                ## reset the cache to the first branch
                #os.system('git-update-index --cacheinfo %s %s %s'
                #          % (file1_mode, file1_hash, path))
            __conflict(path)
            return 1

    # file does not exist in origin
    else:
        # file added in both
        if file1_hash and file2_hash:
            # files are the same
            if file1_hash == file2_hash:
                if os.system('git-update-index --add --cacheinfo %s %s %s'
                             % (file1_mode, file1_hash, path)) != 0:
                    print >> sys.stderr, 'Error: git-update-index failed'
                    __conflict(path)
                    return 1
                if os.system('git-checkout-index -u -f -- %s' % path):
                    print >> sys.stderr, 'Error: git-checkout-index failed'
                    __conflict(path)
                    return 1
                if file1_mode != file2_mode:
                    print >> sys.stderr, \
                          'Error: File "s" added in both, ' \
                          'permissions conflict' % path
                    __conflict(path)
                    return 1
            # files are different
            else:
                # reset the index to the current file
                os.system('git-update-index -- %s' % path)
                print >> sys.stderr, \
                      'Error: File "%s" added in branches but different' % path
                __conflict(path)
                return 1
        # file added in one
        elif file1_hash or file2_hash:
            if file1_hash:
                mode = file1_mode
                obj = file1_hash
            else:
                mode = file2_mode
                obj = file2_hash
            if os.system('git-update-index --add --cacheinfo %s %s %s'
                         % (mode, obj, path)) != 0:
                print >> sys.stderr, 'Error: git-update-index failed'
                __conflict(path)
                return 1
            __remove_files(orig_hash, file1_hash, file2_hash)
            return os.system('git-checkout-index -u -f -- %s' % path)

    # Unhandled case
    print >> sys.stderr, 'Error: Unhandled merge conflict: ' \
          '"%s" "%s" "%s" "%s" "%s" "%s" "%s"' \
          % (orig_hash, file1_hash, file2_hash,
             path,
             orig_mode, file1_mode, file2_mode)
    __conflict(path)
    return 1
Commit	Line	Data
3659ef88 CM	1	"""Performs a 3-way merge for GIT files
	2	"""
	3
	4	__copyright__ = """
	5	Copyright (C) 2006, Catalin Marinas <catalin.marinas@gmail.com>
	6
	7	This program is free software; you can redistribute it and/or modify
	8	it under the terms of the GNU General Public License version 2 as
	9	published by the Free Software Foundation.
	10
	11	This program is distributed in the hope that it will be useful,
	12	but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	GNU General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with this program; if not, write to the Free Software
	18	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	"""
	20
	21	import sys, os
170f576b	22	from stgit import basedir
d7fade4b	23	from stgit.config import config, file_extensions
3659ef88 CM	24	from stgit.utils import append_string
	25
	26
	27	class GitMergeException(Exception):
	28	pass
	29
	30
	31	#
	32	# Options
	33	#
	34	try:
c19dc3db CM	35	merger = config.get('stgit', 'merger')
c19dc3db CM	36	keeporig = config.get('stgit', 'keeporig')
3659ef88 CM	37	except Exception, err:
	38	raise GitMergeException, 'Configuration error: %s' % err
	39
3659ef88 CM	40
	41	#
	42	# Utility functions
	43	#
	44	def __str2none(x):
	45	if x == '':
	46	return None
	47	else:
	48	return x
	49
	50	def __output(cmd):
	51	f = os.popen(cmd, 'r')
	52	string = f.readline().rstrip()
	53	if f.close():
	54	raise GitMergeException, 'Error: failed to execute "%s"' % cmd
	55	return string
	56
	57	def __checkout_files(orig_hash, file1_hash, file2_hash,
	58	path,
	59	orig_mode, file1_mode, file2_mode):
	60	"""Check out the files passed as arguments
	61	"""
	62	global orig, src1, src2
	63
1e075406 CM	64	extensions = file_extensions()
1e075406 CM	65
3659ef88	66	if orig_hash:
1e075406	67	orig = path + extensions['ancestor']
3659ef88 CM	68	tmp = __output('git-unpack-file %s' % orig_hash)
	69	os.chmod(tmp, int(orig_mode, 8))
	70	os.renames(tmp, orig)
	71	if file1_hash:
1e075406	72	src1 = path + extensions['current']
3659ef88 CM	73	tmp = __output('git-unpack-file %s' % file1_hash)
	74	os.chmod(tmp, int(file1_mode, 8))
	75	os.renames(tmp, src1)
	76	if file2_hash:
1e075406	77	src2 = path + extensions['patched']
3659ef88 CM	78	tmp = __output('git-unpack-file %s' % file2_hash)
	79	os.chmod(tmp, int(file2_mode, 8))
	80	os.renames(tmp, src2)
	81
	82	def __remove_files(orig_hash, file1_hash, file2_hash):
	83	"""Remove any temporary files
	84	"""
	85	if orig_hash:
	86	os.remove(orig)
	87	if file1_hash:
	88	os.remove(src1)
	89	if file2_hash:
	90	os.remove(src2)
	91	pass
	92
3659ef88 CM	93	def __conflict(path):
	94	"""Write the conflict file for the 'path' variable and exit
	95	"""
170f576b	96	append_string(os.path.join(basedir.get(), 'conflicts'), path)
3659ef88 CM	97
	98
	99	#
	100	# Main algorithm
	101	#
	102	def merge(orig_hash, file1_hash, file2_hash,
	103	path,
	104	orig_mode, file1_mode, file2_mode):
	105	"""Three-way merge for one file algorithm
	106	"""
	107	__checkout_files(orig_hash, file1_hash, file2_hash,
	108	path,
	109	orig_mode, file1_mode, file2_mode)
	110
	111	# file exists in origin
	112	if orig_hash:
	113	# modified in both
	114	if file1_hash and file2_hash:
	115	# if modes are the same (git-read-tree probably dealt with it)
	116	if file1_hash == file2_hash:
	117	if os.system('git-update-index --cacheinfo %s %s %s'
	118	% (file1_mode, file1_hash, path)) != 0:
	119	print >> sys.stderr, 'Error: git-update-index failed'
	120	__conflict(path)
	121	return 1
	122	if os.system('git-checkout-index -u -f -- %s' % path):
	123	print >> sys.stderr, 'Error: git-checkout-index failed'
	124	__conflict(path)
	125	return 1
	126	if file1_mode != file2_mode:
	127	print >> sys.stderr, \
	128	'Error: File added in both, permissions conflict'
	129	__conflict(path)
	130	return 1
	131	# 3-way merge
	132	else:
	133	merge_ok = os.system(merger % {'branch1': src1,
	134	'ancestor': orig,
	135	'branch2': src2,
	136	'output': path }) == 0
	137
	138	if merge_ok:
	139	os.system('git-update-index -- %s' % path)
	140	__remove_files(orig_hash, file1_hash, file2_hash)
	141	return 0
	142	else:
	143	print >> sys.stderr, \
	144	'Error: three-way merge tool failed for file "%s"' \
	145	% path
	146	# reset the cache to the first branch
	147	os.system('git-update-index --cacheinfo %s %s %s'
	148	% (file1_mode, file1_hash, path))
	149	if keeporig != 'yes':
	150	__remove_files(orig_hash, file1_hash, file2_hash)
	151	__conflict(path)
	152	return 1
	153	# file deleted in both or deleted in one and unchanged in the other
	154	elif not (file1_hash or file2_hash) \
	155	or file1_hash == orig_hash or file2_hash == orig_hash:
	156	if os.path.exists(path):
	157	os.remove(path)
	158	__remove_files(orig_hash, file1_hash, file2_hash)
	159	return os.system('git-update-index --remove -- %s' % path)
	160	# file deleted in one and changed in the other
161	else:
162	# Do something here - we must at least merge the entry in
163	# the cache, instead of leaving it in U(nmerged) state. In
164	# fact, stg resolved does not handle that.
165
166	# Do the same thing cogito does - remove the file in any case.
167	os.system('git-update-index --remove -- %s' % path)
168
169	#if file1_hash:
170	## file deleted upstream and changed in the patch. The
171	## patch is probably going to move the changes
172	## elsewhere.
173
174	#os.system('git-update-index --remove -- %s' % path)
175	#else:
176	## file deleted in the patch and changed upstream. We
177	## could re-delete it, but for now leave it there -
178	## and let the user check if he still wants to remove
179	## the file.
180
181	## reset the cache to the first branch
182	#os.system('git-update-index --cacheinfo %s %s %s'
183	# % (file1_mode, file1_hash, path))
184	__conflict(path)
185	return 1
186
187	# file does not exist in origin
188	else:
189	# file added in both
190	if file1_hash and file2_hash:
191	# files are the same
192	if file1_hash == file2_hash:
193	if os.system('git-update-index --add --cacheinfo %s %s %s'
194	% (file1_mode, file1_hash, path)) != 0:
195	print >> sys.stderr, 'Error: git-update-index failed'
196	__conflict(path)
197	return 1
198	if os.system('git-checkout-index -u -f -- %s' % path):
199	print >> sys.stderr, 'Error: git-checkout-index failed'
200	__conflict(path)
201	return 1
202	if file1_mode != file2_mode:
203	print >> sys.stderr, \
204	'Error: File "s" added in both, ' \
205	'permissions conflict' % path
206	__conflict(path)
207	return 1
208	# files are different
209	else:
56df21ed CM	210	# reset the index to the current file
56df21ed CM	211	os.system('git-update-index -- %s' % path)
3659ef88 CM	212	print >> sys.stderr, \
	213	'Error: File "%s" added in branches but different' % path
	214	__conflict(path)
	215	return 1
	216	# file added in one
	217	elif file1_hash or file2_hash:
	218	if file1_hash:
	219	mode = file1_mode
	220	obj = file1_hash
	221	else:
	222	mode = file2_mode
	223	obj = file2_hash
	224	if os.system('git-update-index --add --cacheinfo %s %s %s'
	225	% (mode, obj, path)) != 0:
	226	print >> sys.stderr, 'Error: git-update-index failed'
	227	__conflict(path)
	228	return 1
	229	__remove_files(orig_hash, file1_hash, file2_hash)
	230	return os.system('git-checkout-index -u -f -- %s' % path)
	231
	232	# Unhandled case
	233	print >> sys.stderr, 'Error: Unhandled merge conflict: ' \
	234	'"%s" "%s" "%s" "%s" "%s" "%s" "%s"' \
	235	% (orig_hash, file1_hash, file2_hash,
	236	path,
	237	orig_mode, file1_mode, file2_mode)
	238	__conflict(path)
	239	return 1