hgext/convert/p4.py

convert: when getting file from Perforce concatenate data at the end

As it turned out, even when getting relatively small files, concatenating
string data every time when new chunk is received is very inefficient.
Maintaining a string list of data chunks and concatenating everything in one go
at the end seems much more efficient - in my testing it made getting 40 MB file
7 times faster, whilst converting of a particularly big changelist with some big
files went down from 20 hours to 3 hours.

# Perforce source for convert extension.
#
# Copyright 2009, Frank Kingswood <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from mercurial import util
from mercurial.i18n import _

from common import commit, converter_source, checktool, NoRepo
import marshal
import re

def loaditer(f):
    "Yield the dictionary objects generated by p4"
    try:
        while True:
            d = marshal.load(f)
            if not d:
                break
            yield d
    except EOFError:
        pass

def decodefilename(filename):
    """Perforce escapes special characters @, #, *, or %
    with %40, %23, %2A, or %25 respectively

    >>> decodefilename('portable-net45%252Bnetcore45%252Bwp8%252BMonoAndroid')
    'portable-net45%2Bnetcore45%2Bwp8%2BMonoAndroid'
    >>> decodefilename('//Depot/Directory/%2525/%2523/%23%40.%2A')
    '//Depot/Directory/%25/%23/#@.*'
    """
    replacements = [('%2A', '*'), ('%23', '#'), ('%40', '@'), ('%25', '%')]
    for k, v in replacements:
        filename = filename.replace(k, v)
    return filename

class p4_source(converter_source):
    def __init__(self, ui, path, revs=None):
        super(p4_source, self).__init__(ui, path, revs=revs)

        if "/" in path and not path.startswith('//'):
            raise NoRepo(_('%s does not look like a P4 repository') % path)

        checktool('p4', abort=False)

        self.p4changes = {}
        self.heads = {}
        self.changeset = {}
        self.files = {}
        self.copies = {}
        self.tags = {}
        self.lastbranch = {}
        self.parent = {}
        self.encoding = "latin_1"
        self.depotname = {}           # mapping from local name to depot name
        self.localname = {} # mapping from depot name to local name
        self.re_type = re.compile(
            "([a-z]+)?(text|binary|symlink|apple|resource|unicode|utf\d+)"
            "(\+\w+)?$")
        self.re_keywords = re.compile(
            r"\$(Id|Header|Date|DateTime|Change|File|Revision|Author)"
            r":[^$\n]*\$")
        self.re_keywords_old = re.compile("\$(Id|Header):[^$\n]*\$")

        if revs and len(revs) > 1:
            raise util.Abort(_("p4 source does not support specifying "
                               "multiple revisions"))
        self._parse(ui, path)

    def _parse_view(self, path):
        "Read changes affecting the path"
        cmd = 'p4 -G changes -s submitted %s' % util.shellquote(path)
        stdout = util.popen(cmd, mode='rb')
        for d in loaditer(stdout):
            c = d.get("change", None)
            if c:
                self.p4changes[c] = True

    def _parse(self, ui, path):
        "Prepare list of P4 filenames and revisions to import"
        ui.status(_('reading p4 views\n'))

        # read client spec or view
        if "/" in path:
            self._parse_view(path)
            if path.startswith("//") and path.endswith("/..."):
                views = {path[:-3]:""}
            else:
                views = {"//": ""}
        else:
            cmd = 'p4 -G client -o %s' % util.shellquote(path)
            clientspec = marshal.load(util.popen(cmd, mode='rb'))

            views = {}
            for client in clientspec:
                if client.startswith("View"):
                    sview, cview = clientspec[client].split()
                    self._parse_view(sview)
                    if sview.endswith("...") and cview.endswith("..."):
                        sview = sview[:-3]
                        cview = cview[:-3]
                    cview = cview[2:]
                    cview = cview[cview.find("/") + 1:]
                    views[sview] = cview

        # list of changes that affect our source files
        self.p4changes = self.p4changes.keys()
        self.p4changes.sort(key=int)

        # list with depot pathnames, longest first
        vieworder = views.keys()
        vieworder.sort(key=len, reverse=True)

        # handle revision limiting
        startrev = self.ui.config('convert', 'p4.startrev', default=0)
        self.p4changes = [x for x in self.p4changes
                          if ((not startrev or int(x) >= int(startrev)) and
                              (not self.revs or int(x) <= int(self.revs[0])))]

        # now read the full changelists to get the list of file revisions
        ui.status(_('collecting p4 changelists\n'))
        lastid = None
        for change in self.p4changes:
            cmd = "p4 -G describe -s %s" % change
            stdout = util.popen(cmd, mode='rb')
            d = marshal.load(stdout)
            desc = self.recode(d.get("desc", ""))
            shortdesc = desc.split("\n", 1)[0]
            t = '%s %s' % (d["change"], repr(shortdesc)[1:-1])
            ui.status(util.ellipsis(t, 80) + '\n')

            if lastid:
                parents = [lastid]
            else:
                parents = []

            date = (int(d["time"]), 0)     # timezone not set
            c = commit(author=self.recode(d["user"]),
                       date=util.datestr(date, '%Y-%m-%d %H:%M:%S %1%2'),
                       parents=parents, desc=desc, branch=None,
                       extra={"p4": change})

            files = []
            copies = {}
            copiedfiles = []
            i = 0
            while ("depotFile%d" % i) in d and ("rev%d" % i) in d:
                oldname = d["depotFile%d" % i]
                filename = None
                for v in vieworder:
                    if oldname.lower().startswith(v.lower()):
                        filename = decodefilename(views[v] + oldname[len(v):])
                        break
                if filename:
                    files.append((filename, d["rev%d" % i]))
                    self.depotname[filename] = oldname
                    if (d.get("action%d" % i) == "move/add"):
                        copiedfiles.append(filename)
                    self.localname[oldname] = filename
                i += 1

            # Collect information about copied files
            for filename in copiedfiles:
                oldname = self.depotname[filename]

                flcmd = 'p4 -G filelog %s' \
                      % util.shellquote(oldname)
                flstdout = util.popen(flcmd, mode='rb')

                copiedfilename = None
                for d in loaditer(flstdout):
                    copiedoldname = None

                    i = 0
                    while ("change%d" % i) in d:
                        if (d["change%d" % i] == change and
                            d["action%d" % i] == "move/add"):
                            j = 0
                            while ("file%d,%d" % (i, j)) in d:
                                if d["how%d,%d" % (i, j)] == "moved from":
                                    copiedoldname = d["file%d,%d" % (i, j)]
                                    break
                                j += 1
                        i += 1

                    if copiedoldname and copiedoldname in self.localname:
                        copiedfilename = self.localname[copiedoldname]
                        break

                if copiedfilename:
                    copies[filename] = copiedfilename
                else:
                    ui.warn(_("cannot find source for copied file: %s@%s\n")
                            % (filename, change))

            self.changeset[change] = c
            self.files[change] = files
            self.copies[change] = copies
            lastid = change

        if lastid:
            self.heads = [lastid]

    def getheads(self):
        return self.heads

    def getfile(self, name, rev):
        cmd = 'p4 -G print %s' \
            % util.shellquote("%s#%s" % (self.depotname[name], rev))

        lasterror = None
        while True:
            stdout = util.popen(cmd, mode='rb')

            mode = None
            contents = []
            keywords = None

            for d in loaditer(stdout):
                code = d["code"]
                data = d.get("data")

                if code == "error":
                    # if this is the first time error happened
                    # re-attempt getting the file
                    if not lasterror:
                        lasterror = IOError(d["generic"], data)
                        # this will exit inner-most for-loop
                        break
                    else:
                        raise lasterror

                elif code == "stat":
                    action = d.get("action")
                    if action in ["purge", "delete", "move/delete"]:
                        return None, None
                    p4type = self.re_type.match(d["type"])
                    if p4type:
                        mode = ""
                        flags = ((p4type.group(1) or "")
                               + (p4type.group(3) or ""))
                        if "x" in flags:
                            mode = "x"
                        if p4type.group(2) == "symlink":
                            mode = "l"
                        if "ko" in flags:
                            keywords = self.re_keywords_old
                        elif "k" in flags:
                            keywords = self.re_keywords

                elif code == "text" or code == "binary":
                    contents.append(data)

                lasterror = None

            if not lasterror:
                break

        if mode is None:
            return None, None

        contents = ''.join(contents)

        if keywords:
            contents = keywords.sub("$\\1$", contents)
        if mode == "l" and contents.endswith("\n"):
            contents = contents[:-1]

        return contents, mode

    def getchanges(self, rev, full):
        if full:
            raise util.Abort(_("convert from p4 do not support --full"))
        return self.files[rev], self.copies[rev], set()

    def getcommit(self, rev):
        return self.changeset[rev]

    def gettags(self):
        return self.tags

    def getchangedfiles(self, rev, i):
        return sorted([x[0] for x in self.files[rev]])