| # coding=utf-8 |
| # Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| """Utility functions to handle patches.""" |
| |
| import posixpath |
| import os |
| import re |
| |
| |
| class UnsupportedPatchFormat(Exception): |
| def __init__(self, filename, status): |
| super(UnsupportedPatchFormat, self).__init__(filename, status) |
| self.filename = filename |
| self.status = status |
| |
| def __str__(self): |
| out = 'Can\'t process patch for file %s.' % self.filename |
| if self.status: |
| out += '\n%s' % self.status |
| return out |
| |
| |
| class FilePatchBase(object): |
| """Defines a single file being modified. |
| |
| '/' is always used instead of os.sep for consistency. |
| """ |
| is_delete = False |
| is_binary = False |
| is_new = False |
| |
| def __init__(self, filename): |
| assert self.__class__ is not FilePatchBase |
| self.filename = self._process_filename(filename) |
| # Set when the file is copied or moved. |
| self.source_filename = None |
| |
| @property |
| def filename_utf8(self): |
| return self.filename.encode('utf-8') |
| |
| @property |
| def source_filename_utf8(self): |
| if self.source_filename is not None: |
| return self.source_filename.encode('utf-8') |
| |
| @staticmethod |
| def _process_filename(filename): |
| filename = filename.replace('\\', '/') |
| # Blacklist a few characters for simplicity. |
| for i in ('$', '..', '\'', '"', '<', '>', ':', '|', '?', '*'): |
| if i in filename: |
| raise UnsupportedPatchFormat( |
| filename, 'Can\'t use \'%s\' in filename.' % i) |
| if filename.startswith('/'): |
| raise UnsupportedPatchFormat( |
| filename, 'Filename can\'t start with \'/\'.') |
| if filename == 'CON': |
| raise UnsupportedPatchFormat( |
| filename, 'Filename can\'t be \'CON\'.') |
| if re.match(r'COM\d', filename): |
| raise UnsupportedPatchFormat( |
| filename, 'Filename can\'t be \'%s\'.' % filename) |
| return filename |
| |
| def set_relpath(self, relpath): |
| if not relpath: |
| return |
| relpath = relpath.replace('\\', '/') |
| if relpath[0] == '/': |
| self._fail('Relative path starts with %s' % relpath[0]) |
| self.filename = self._process_filename( |
| posixpath.join(relpath, self.filename)) |
| if self.source_filename: |
| self.source_filename = self._process_filename( |
| posixpath.join(relpath, self.source_filename)) |
| |
| def _fail(self, msg): |
| """Shortcut function to raise UnsupportedPatchFormat.""" |
| raise UnsupportedPatchFormat(self.filename, msg) |
| |
| def __str__(self): |
| # Use a status-like board. |
| out = '' |
| if self.is_binary: |
| out += 'B' |
| else: |
| out += ' ' |
| if self.is_delete: |
| out += 'D' |
| else: |
| out += ' ' |
| if self.is_new: |
| out += 'N' |
| else: |
| out += ' ' |
| if self.source_filename: |
| out += 'R' |
| else: |
| out += ' ' |
| out += ' ' |
| if self.source_filename: |
| out += '%s->' % self.source_filename_utf8 |
| return out + self.filename_utf8 |
| |
| def dump(self): |
| """Dumps itself in a verbose way to help diagnosing.""" |
| return str(self) |
| |
| |
| class FilePatchDelete(FilePatchBase): |
| """Deletes a file.""" |
| is_delete = True |
| |
| def __init__(self, filename, is_binary): |
| super(FilePatchDelete, self).__init__(filename) |
| self.is_binary = is_binary |
| |
| |
| class FilePatchBinary(FilePatchBase): |
| """Content of a new binary file.""" |
| is_binary = True |
| |
| def __init__(self, filename, data, svn_properties, is_new): |
| super(FilePatchBinary, self).__init__(filename) |
| self.data = data |
| self.svn_properties = svn_properties or [] |
| self.is_new = is_new |
| |
| def get(self): |
| return self.data |
| |
| def __str__(self): |
| return str(super(FilePatchBinary, self)) + ' %d bytes' % len(self.data) |
| |
| |
| class Hunk(object): |
| """Parsed hunk data container.""" |
| |
| def __init__(self, start_src, lines_src, start_dst, lines_dst): |
| self.start_src = start_src |
| self.lines_src = lines_src |
| self.start_dst = start_dst |
| self.lines_dst = lines_dst |
| self.variation = self.lines_dst - self.lines_src |
| self.text = [] |
| |
| def __repr__(self): |
| return '%s<(%d, %d) to (%d, %d)>' % ( |
| self.__class__.__name__, |
| self.start_src, self.lines_src, self.start_dst, self.lines_dst) |
| |
| |
| class FilePatchDiff(FilePatchBase): |
| """Patch for a single file.""" |
| |
| def __init__(self, filename, diff, svn_properties): |
| super(FilePatchDiff, self).__init__(filename) |
| if not diff: |
| self._fail('File doesn\'t have a diff.') |
| self.diff_header, self.diff_hunks = self._split_header(diff) |
| self.svn_properties = svn_properties or [] |
| self.is_git_diff = self._is_git_diff_header(self.diff_header) |
| self.patchlevel = 0 |
| if self.is_git_diff: |
| self._verify_git_header() |
| else: |
| self._verify_svn_header() |
| self.hunks = self._split_hunks() |
| if self.source_filename and not self.is_new: |
| self._fail('If source_filename is set, is_new must be also be set') |
| |
| def get(self, for_git): |
| if for_git or not self.source_filename: |
| return self.diff_header + self.diff_hunks |
| else: |
| # patch is stupid. It patches the source_filename instead so get rid of |
| # any source_filename reference if needed. |
| return ( |
| self.diff_header.replace( |
| self.source_filename_utf8, self.filename_utf8) + |
| self.diff_hunks) |
| |
| def set_relpath(self, relpath): |
| old_filename = self.filename_utf8 |
| old_source_filename = self.source_filename_utf8 or self.filename_utf8 |
| super(FilePatchDiff, self).set_relpath(relpath) |
| # Update the header too. |
| filename = self.filename_utf8 |
| source_filename = self.source_filename_utf8 or self.filename_utf8 |
| lines = self.diff_header.splitlines(True) |
| for i, line in enumerate(lines): |
| if line.startswith('diff --git'): |
| lines[i] = line.replace( |
| 'a/' + old_source_filename, source_filename).replace( |
| 'b/' + old_filename, filename) |
| elif re.match(r'^\w+ from .+$', line) or line.startswith('---'): |
| lines[i] = line.replace(old_source_filename, source_filename) |
| elif re.match(r'^\w+ to .+$', line) or line.startswith('+++'): |
| lines[i] = line.replace(old_filename, filename) |
| self.diff_header = ''.join(lines) |
| |
| def _split_header(self, diff): |
| """Splits a diff in two: the header and the hunks.""" |
| header = [] |
| hunks = diff.splitlines(True) |
| while hunks: |
| header.append(hunks.pop(0)) |
| if header[-1].startswith('--- '): |
| break |
| else: |
| # Some diff may not have a ---/+++ set like a git rename with no change or |
| # a svn diff with only property change. |
| pass |
| |
| if hunks: |
| if not hunks[0].startswith('+++ '): |
| self._fail('Inconsistent header') |
| header.append(hunks.pop(0)) |
| if hunks: |
| if not hunks[0].startswith('@@ '): |
| self._fail('Inconsistent hunk header') |
| |
| # Mangle any \\ in the header to /. |
| header_lines = ('Index:', 'diff', 'copy', 'rename', '+++', '---') |
| basename = os.path.basename(self.filename_utf8) |
| for i in xrange(len(header)): |
| if (header[i].split(' ', 1)[0] in header_lines or |
| header[i].endswith(basename)): |
| header[i] = header[i].replace('\\', '/') |
| return ''.join(header), ''.join(hunks) |
| |
| @staticmethod |
| def _is_git_diff_header(diff_header): |
| """Returns True if the diff for a single files was generated with git.""" |
| # Delete: http://codereview.chromium.org/download/issue6368055_22_29.diff |
| # Rename partial change: |
| # http://codereview.chromium.org/download/issue6250123_3013_6010.diff |
| # Rename no change: |
| # http://codereview.chromium.org/download/issue6287022_3001_4010.diff |
| return any(l.startswith('diff --git') for l in diff_header.splitlines()) |
| |
| def _split_hunks(self): |
| """Splits the hunks and does verification.""" |
| hunks = [] |
| for line in self.diff_hunks.splitlines(True): |
| if line.startswith('@@'): |
| match = re.match(r'^@@ -([\d,]+) \+([\d,]+) @@.*$', line) |
| # File add will result in "-0,0 +1" but file deletion will result in |
| # "-1,N +0,0" where N is the number of lines deleted. That's from diff |
| # and svn diff. git diff doesn't exhibit this behavior. |
| # svn diff for a single line file rewrite "@@ -1 +1 @@". Fun. |
| # "@@ -1 +1,N @@" is also valid where N is the length of the new file. |
| if not match: |
| self._fail('Hunk header is unparsable') |
| count = match.group(1).count(',') |
| if not count: |
| start_src = int(match.group(1)) |
| lines_src = 1 |
| elif count == 1: |
| start_src, lines_src = map(int, match.group(1).split(',', 1)) |
| else: |
| self._fail('Hunk header is malformed') |
| |
| count = match.group(2).count(',') |
| if not count: |
| start_dst = int(match.group(2)) |
| lines_dst = 1 |
| elif count == 1: |
| start_dst, lines_dst = map(int, match.group(2).split(',', 1)) |
| else: |
| self._fail('Hunk header is malformed') |
| new_hunk = Hunk(start_src, lines_src, start_dst, lines_dst) |
| if hunks: |
| if new_hunk.start_src <= hunks[-1].start_src: |
| self._fail('Hunks source lines are not ordered') |
| if new_hunk.start_dst <= hunks[-1].start_dst: |
| self._fail('Hunks destination lines are not ordered') |
| hunks.append(new_hunk) |
| continue |
| hunks[-1].text.append(line) |
| |
| if len(hunks) == 1: |
| if hunks[0].start_src == 0 and hunks[0].lines_src == 0: |
| self.is_new = True |
| if hunks[0].start_dst == 0 and hunks[0].lines_dst == 0: |
| self.is_delete = True |
| |
| if self.is_new and self.is_delete: |
| self._fail('Hunk header is all 0') |
| |
| if not self.is_new and not self.is_delete: |
| for hunk in hunks: |
| variation = ( |
| len([1 for i in hunk.text if i.startswith('+')]) - |
| len([1 for i in hunk.text if i.startswith('-')])) |
| if variation != hunk.variation: |
| self._fail( |
| 'Hunk header is incorrect: %d vs %d; %r' % ( |
| variation, hunk.variation, hunk)) |
| if not hunk.start_src: |
| self._fail( |
| 'Hunk header start line is incorrect: %d' % hunk.start_src) |
| if not hunk.start_dst: |
| self._fail( |
| 'Hunk header start line is incorrect: %d' % hunk.start_dst) |
| hunk.start_src -= 1 |
| hunk.start_dst -= 1 |
| if self.is_new and hunks: |
| hunks[0].start_dst -= 1 |
| if self.is_delete and hunks: |
| hunks[0].start_src -= 1 |
| return hunks |
| |
| def mangle(self, string): |
| """Mangle a file path.""" |
| return '/'.join(string.replace('\\', '/').split('/')[self.patchlevel:]) |
| |
| def _verify_git_header(self): |
| """Sanity checks the header. |
| |
| Expects the following format: |
| |
| <garbage> |
| diff --git (|a/)<filename> (|b/)<filename> |
| <similarity> |
| <filemode changes> |
| <index> |
| <copy|rename from> |
| <copy|rename to> |
| --- <filename> |
| +++ <filename> |
| |
| Everything is optional except the diff --git line. |
| """ |
| lines = self.diff_header.splitlines() |
| |
| # Verify the diff --git line. |
| old = None |
| new = None |
| while lines: |
| match = re.match(r'^diff \-\-git (.*?) (.*)$', lines.pop(0)) |
| if not match: |
| continue |
| if match.group(1).startswith('a/') and match.group(2).startswith('b/'): |
| self.patchlevel = 1 |
| old = self.mangle(match.group(1)) |
| new = self.mangle(match.group(2)) |
| |
| # The rename is about the new file so the old file can be anything. |
| if new not in (self.filename_utf8, 'dev/null'): |
| self._fail('Unexpected git diff output name %s.' % new) |
| if old == 'dev/null' and new == 'dev/null': |
| self._fail('Unexpected /dev/null git diff.') |
| break |
| |
| if not old or not new: |
| self._fail('Unexpected git diff; couldn\'t find git header.') |
| |
| if old not in (self.filename_utf8, 'dev/null'): |
| # Copy or rename. |
| self.source_filename = old.decode('utf-8') |
| self.is_new = True |
| |
| last_line = '' |
| |
| while lines: |
| line = lines.pop(0) |
| self._verify_git_header_process_line(lines, line, last_line) |
| last_line = line |
| |
| # Cheap check to make sure the file name is at least mentioned in the |
| # 'diff' header. That the only remaining invariant. |
| if not self.filename_utf8 in self.diff_header: |
| self._fail('Diff seems corrupted.') |
| |
| def _verify_git_header_process_line(self, lines, line, last_line): |
| """Processes a single line of the header. |
| |
| Returns True if it should continue looping. |
| |
| Format is described to |
| http://www.kernel.org/pub/software/scm/git/docs/git-diff.html |
| """ |
| match = re.match(r'^(rename|copy) from (.+)$', line) |
| old = self.source_filename_utf8 or self.filename_utf8 |
| if match: |
| if old != match.group(2): |
| self._fail('Unexpected git diff input name for line %s.' % line) |
| if not lines or not lines[0].startswith('%s to ' % match.group(1)): |
| self._fail( |
| 'Confused %s from/to git diff for line %s.' % |
| (match.group(1), line)) |
| return |
| |
| match = re.match(r'^(rename|copy) to (.+)$', line) |
| if match: |
| if self.filename_utf8 != match.group(2): |
| self._fail('Unexpected git diff output name for line %s.' % line) |
| if not last_line.startswith('%s from ' % match.group(1)): |
| self._fail( |
| 'Confused %s from/to git diff for line %s.' % |
| (match.group(1), line)) |
| return |
| |
| match = re.match(r'^deleted file mode (\d{6})$', line) |
| if match: |
| # It is necessary to parse it because there may be no hunk, like when the |
| # file was empty. |
| self.is_delete = True |
| return |
| |
| match = re.match(r'^new(| file) mode (\d{6})$', line) |
| if match: |
| mode = match.group(2) |
| # Only look at owner ACL for executable. |
| if bool(int(mode[4]) & 1): |
| self.svn_properties.append(('svn:executable', '.')) |
| elif not self.source_filename and self.is_new: |
| # It's a new file, not from a rename/copy, then there's no property to |
| # delete. |
| self.svn_properties.append(('svn:executable', None)) |
| return |
| |
| match = re.match(r'^--- (.*)$', line) |
| if match: |
| if last_line[:3] in ('---', '+++'): |
| self._fail('--- and +++ are reversed') |
| if match.group(1) == '/dev/null': |
| self.is_new = True |
| elif self.mangle(match.group(1)) != old: |
| # git patches are always well formatted, do not allow random filenames. |
| self._fail('Unexpected git diff: %s != %s.' % (old, match.group(1))) |
| if not lines or not lines[0].startswith('+++'): |
| self._fail('Missing git diff output name.') |
| return |
| |
| match = re.match(r'^\+\+\+ (.*)$', line) |
| if match: |
| if not last_line.startswith('---'): |
| self._fail('Unexpected git diff: --- not following +++.') |
| if '/dev/null' == match.group(1): |
| self.is_delete = True |
| elif self.filename_utf8 != self.mangle(match.group(1)): |
| self._fail( |
| 'Unexpected git diff: %s != %s.' % (self.filename, match.group(1))) |
| if lines: |
| self._fail('Crap after +++') |
| # We're done. |
| return |
| |
| def _verify_svn_header(self): |
| """Sanity checks the header. |
| |
| A svn diff can contain only property changes, in that case there will be no |
| proper header. To make things worse, this property change header is |
| localized. |
| """ |
| lines = self.diff_header.splitlines() |
| last_line = '' |
| |
| while lines: |
| line = lines.pop(0) |
| self._verify_svn_header_process_line(lines, line, last_line) |
| last_line = line |
| |
| # Cheap check to make sure the file name is at least mentioned in the |
| # 'diff' header. That the only remaining invariant. |
| if not self.filename_utf8 in self.diff_header: |
| self._fail('Diff seems corrupted.') |
| |
| def _verify_svn_header_process_line(self, lines, line, last_line): |
| """Processes a single line of the header. |
| |
| Returns True if it should continue looping. |
| """ |
| match = re.match(r'^--- ([^\t]+).*$', line) |
| if match: |
| if last_line[:3] in ('---', '+++'): |
| self._fail('--- and +++ are reversed') |
| if match.group(1) == '/dev/null': |
| self.is_new = True |
| elif self.mangle(match.group(1)) != self.filename_utf8: |
| # guess the source filename. |
| self.source_filename = match.group(1).decode('utf-8') |
| self.is_new = True |
| if not lines or not lines[0].startswith('+++'): |
| self._fail('Nothing after header.') |
| return |
| |
| match = re.match(r'^\+\+\+ ([^\t]+).*$', line) |
| if match: |
| if not last_line.startswith('---'): |
| self._fail('Unexpected diff: --- not following +++.') |
| if match.group(1) == '/dev/null': |
| self.is_delete = True |
| elif self.mangle(match.group(1)) != self.filename_utf8: |
| self._fail('Unexpected diff: %s.' % match.group(1)) |
| if lines: |
| self._fail('Crap after +++') |
| # We're done. |
| return |
| |
| def dump(self): |
| """Dumps itself in a verbose way to help diagnosing.""" |
| return str(self) + '\n' + self.get(True) |
| |
| |
| class PatchSet(object): |
| """A list of FilePatch* objects.""" |
| |
| def __init__(self, patches): |
| for p in patches: |
| assert isinstance(p, FilePatchBase) |
| |
| def key(p): |
| """Sort by ordering of application. |
| |
| File move are first. |
| Deletes are last. |
| """ |
| # The bool is necessary because None < 'string' but the reverse is needed. |
| return ( |
| p.is_delete, |
| # False is before True, so files *with* a source file will be first. |
| not bool(p.source_filename), |
| p.source_filename_utf8, |
| p.filename_utf8) |
| |
| self.patches = sorted(patches, key=key) |
| |
| def set_relpath(self, relpath): |
| """Used to offset the patch into a subdirectory.""" |
| for patch in self.patches: |
| patch.set_relpath(relpath) |
| |
| def __iter__(self): |
| for patch in self.patches: |
| yield patch |
| |
| def __getitem__(self, key): |
| return self.patches[key] |
| |
| @property |
| def filenames(self): |
| return [p.filename for p in self.patches] |
