author | Yuya Nishihara <yuya@tcha.org> |
Fri, 20 Mar 2015 00:22:37 +0900 | |
changeset 24389 | 93d3e1a8bfb0 |
parent 24255 | 4bfe9f2d9761 |
child 25948 | 34bd1a5eef5b |
permissions | -rw-r--r-- |
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# filelog.py - file history class for mercurial |
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# |
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# Copyright 2005-2007 Matt Mackall <mpm@selenic.com> |
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# |
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# This software may be used and distributed according to the terms of the |
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# GNU General Public License version 2 or any later version. |
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import error, mdiff, revlog |
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import re, struct |
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_mdre = re.compile('\1\n') |
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def parsemeta(text): |
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"""return (metadatadict, keylist, metadatasize)""" |
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# text can be buffer, so we can't use .startswith or .index |
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if text[:2] != '\1\n': |
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return None, None |
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s = _mdre.search(text, 2).start() |
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mtext = text[2:s] |
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meta = {} |
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for l in mtext.splitlines(): |
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k, v = l.split(": ", 1) |
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meta[k] = v |
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return meta, (s + 2) |
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def packmeta(meta, text): |
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keys = sorted(meta.iterkeys()) |
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metatext = "".join("%s: %s\n" % (k, meta[k]) for k in keys) |
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return "\1\n%s\1\n%s" % (metatext, text) |
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def _censoredtext(text): |
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m, offs = parsemeta(text) |
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return m and "censored" in m |
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class filelog(revlog.revlog): |
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def __init__(self, opener, path): |
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super(filelog, self).__init__(opener, |
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"/".join(("data", path + ".i"))) |
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def read(self, node): |
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t = self.revision(node) |
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if not t.startswith('\1\n'): |
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return t |
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s = t.index('\1\n', 2) |
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return t[s + 2:] |
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def add(self, text, meta, transaction, link, p1=None, p2=None): |
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if meta or text.startswith('\1\n'): |
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text = packmeta(meta, text) |
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return self.addrevision(text, transaction, link, p1, p2) |
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def renamed(self, node): |
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if self.parents(node)[0] != revlog.nullid: |
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return False |
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t = self.revision(node) |
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m = parsemeta(t)[0] |
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if m and "copy" in m: |
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return (m["copy"], revlog.bin(m["copyrev"])) |
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return False |
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def size(self, rev): |
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"""return the size of a given revision""" |
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# for revisions with renames, we have to go the slow way |
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node = self.node(rev) |
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if self.renamed(node): |
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return len(self.read(node)) |
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if self.iscensored(rev): |
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return 0 |
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# XXX if self.read(node).startswith("\1\n"), this returns (size+4) |
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return super(filelog, self).size(rev) |
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def cmp(self, node, text): |
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"""compare text with a given file revision |
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returns True if text is different than what is stored. |
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""" |
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t = text |
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if text.startswith('\1\n'): |
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t = '\1\n\1\n' + text |
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samehashes = not super(filelog, self).cmp(node, t) |
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if samehashes: |
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return False |
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# censored files compare against the empty file |
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if self.iscensored(self.rev(node)): |
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return text != '' |
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# renaming a file produces a different hash, even if the data |
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# remains unchanged. Check if it's the case (slow): |
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if self.renamed(node): |
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t2 = self.read(node) |
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return t2 != text |
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return True |
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def checkhash(self, text, p1, p2, node, rev=None): |
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try: |
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super(filelog, self).checkhash(text, p1, p2, node, rev=rev) |
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except error.RevlogError: |
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if _censoredtext(text): |
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raise error.CensoredNodeError(self.indexfile, node, text) |
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raise |
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def iscensored(self, rev): |
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"""Check if a file revision is censored.""" |
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return self.flags(rev) & revlog.REVIDX_ISCENSORED |
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def _peek_iscensored(self, baserev, delta, flush): |
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"""Quickly check if a delta produces a censored revision.""" |
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# Fragile heuristic: unless new file meta keys are added alphabetically |
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# preceding "censored", all censored revisions are prefixed by |
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# "\1\ncensored:". A delta producing such a censored revision must be a |
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parents:
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changeset
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116 |
# full-replacement delta, so we inspect the first and only patch in the |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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117 |
# delta for this prefix. |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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118 |
hlen = struct.calcsize(">lll") |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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119 |
if len(delta) <= hlen: |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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120 |
return False |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
Mike Edgar <adgar@google.com>
parents:
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changeset
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121 |
|
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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122 |
oldlen = self.rawsize(baserev) |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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123 |
newlen = len(delta) - hlen |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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124 |
if delta[:hlen] != mdiff.replacediffheader(oldlen, newlen): |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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125 |
return False |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
Mike Edgar <adgar@google.com>
parents:
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changeset
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126 |
|
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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127 |
add = "\1\ncensored:" |
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revlog: addgroup checks if incoming deltas add censored revs, sets flag bit
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parents:
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changeset
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128 |
addlen = len(add) |
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parents:
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129 |
return newlen >= addlen and delta[hlen:hlen + addlen] == add |