mercurial/filelog.py
author Alexis S. L. Carvalho <alexis@cecm.usp.br>
Tue, 05 Jun 2007 19:55:27 -0300
changeset 4508 0026ccc2bf23
parent 4267 b11a2fb59cf5
child 4635 63b9d2deed48
permissions -rw-r--r--
Remove atomicfile class. The interface provided by opener(atomic=True) is inherently unsafe: if an exception is raised in the code using the atomic file, the possibly incomplete file will be renamed to its final destination, defeating the whole purpose of atomic files. To get around this, we would either need some bad hacks involving sys.exc_info (to make sure things work in except: blocks), or an interface to say "file is complete; rename it". This is the exact interface provided by atomictempfile. Since there are no remaining users of the atomicfile class, just remove it.

# filelog.py - file history class for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.

from revlog import *
import os

class filelog(revlog):
    def __init__(self, opener, path):
        revlog.__init__(self, opener,
                        "/".join(("data", self.encodedir(path + ".i"))))

    # This avoids a collision between a file named foo and a dir named
    # foo.i or foo.d
    def encodedir(self, path):
        return (path
                .replace(".hg/", ".hg.hg/")
                .replace(".i/", ".i.hg/")
                .replace(".d/", ".d.hg/"))

    def decodedir(self, path):
        return (path
                .replace(".d.hg/", ".d/")
                .replace(".i.hg/", ".i/")
                .replace(".hg.hg/", ".hg/"))

    def read(self, node):
        t = self.revision(node)
        if not t.startswith('\1\n'):
            return t
        s = t.index('\1\n', 2)
        return t[s+2:]

    def _readmeta(self, node):
        t = self.revision(node)
        if not t.startswith('\1\n'):
            return {}
        s = t.index('\1\n', 2)
        mt = t[2:s]
        m = {}
        for l in mt.splitlines():
            k, v = l.split(": ", 1)
            m[k] = v
        return m

    def add(self, text, meta, transaction, link, p1=None, p2=None):
        if meta or text.startswith('\1\n'):
            mt = ""
            if meta:
                mt = [ "%s: %s\n" % (k, v) for k,v in meta.items() ]
            text = "\1\n%s\1\n%s" % ("".join(mt), text)
        return self.addrevision(text, transaction, link, p1, p2)

    def renamed(self, node):
        if self.parents(node)[0] != nullid:
            return False
        m = self._readmeta(node)
        if m and m.has_key("copy"):
            return (m["copy"], bin(m["copyrev"]))
        return False

    def size(self, rev):
        """return the size of a given revision"""

        # for revisions with renames, we have to go the slow way
        node = self.node(rev)
        if self.renamed(node):
            return len(self.read(node))

        return revlog.size(self, rev)

    def cmp(self, node, text):
        """compare text with a given file revision"""

        # for renames, we have to go the slow way
        if self.renamed(node):
            t2 = self.read(node)
            return t2 != text

        return revlog.cmp(self, node, text)