/git-p4.py

Large files files are truncated, but you can click here to view the full file

#!/usr/bin/env python
#
# git-p4.py -- A tool for bidirectional operation between a Perforce depot and git.
#
# Author: Simon Hausmann <simon@lst.de>
# Copyright: 2007 Simon Hausmann <simon@lst.de>
#            2007 Trolltech ASA
# License: MIT <http://www.opensource.org/licenses/mit-license.php>
#
import sys
if sys.hexversion < 0x02040000:
    # The limiter is the subprocess module
    sys.stderr.write("git-p4: requires Python 2.4 or later.\n")
    sys.exit(1)
import os
import optparse
import marshal
import subprocess
import tempfile
import time
import platform
import re
import shutil
import stat
import zipfile
import zlib
import ctypes

try:
    from subprocess import CalledProcessError
except ImportError:
    # from python2.7:subprocess.py
    # Exception classes used by this module.
    class CalledProcessError(Exception):
        """This exception is raised when a process run by check_call() returns
        a non-zero exit status.  The exit status will be stored in the
        returncode attribute."""
        def __init__(self, returncode, cmd):
            self.returncode = returncode
            self.cmd = cmd
        def __str__(self):
            return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)

verbose = False

# Only labels/tags matching this will be imported/exported
defaultLabelRegexp = r'[a-zA-Z0-9_\-.]+$'

# Grab changes in blocks of this many revisions, unless otherwise requested
defaultBlockSize = 512

def p4_build_cmd(cmd):
    """Build a suitable p4 command line.

    This consolidates building and returning a p4 command line into one
    location. It means that hooking into the environment, or other configuration
    can be done more easily.
    """
    real_cmd = ["p4"]

    user = gitConfig("git-p4.user")
    if len(user) > 0:
        real_cmd += ["-u",user]

    password = gitConfig("git-p4.password")
    if len(password) > 0:
        real_cmd += ["-P", password]

    port = gitConfig("git-p4.port")
    if len(port) > 0:
        real_cmd += ["-p", port]

    host = gitConfig("git-p4.host")
    if len(host) > 0:
        real_cmd += ["-H", host]

    client = gitConfig("git-p4.client")
    if len(client) > 0:
        real_cmd += ["-c", client]


    if isinstance(cmd,basestring):
        real_cmd = ' '.join(real_cmd) + ' ' + cmd
    else:
        real_cmd += cmd
    return real_cmd

def chdir(path, is_client_path=False):
    """Do chdir to the given path, and set the PWD environment
       variable for use by P4.  It does not look at getcwd() output.
       Since we're not using the shell, it is necessary to set the
       PWD environment variable explicitly.

       Normally, expand the path to force it to be absolute.  This
       addresses the use of relative path names inside P4 settings,
       e.g. P4CONFIG=.p4config.  P4 does not simply open the filename
       as given; it looks for .p4config using PWD.

       If is_client_path, the path was handed to us directly by p4,
       and may be a symbolic link.  Do not call os.getcwd() in this
       case, because it will cause p4 to think that PWD is not inside
       the client path.
       """

    os.chdir(path)
    if not is_client_path:
        path = os.getcwd()
    os.environ['PWD'] = path

def calcDiskFree():
    """Return free space in bytes on the disk of the given dirname."""
    if platform.system() == 'Windows':
        free_bytes = ctypes.c_ulonglong(0)
        ctypes.windll.kernel32.GetDiskFreeSpaceExW(ctypes.c_wchar_p(os.getcwd()), None, None, ctypes.pointer(free_bytes))
        return free_bytes.value
    else:
        st = os.statvfs(os.getcwd())
        return st.f_bavail * st.f_frsize

def die(msg):
    if verbose:
        raise Exception(msg)
    else:
        sys.stderr.write(msg + "\n")
        sys.exit(1)

def write_pipe(c, stdin):
    if verbose:
        sys.stderr.write('Writing pipe: %s\n' % str(c))

    expand = isinstance(c,basestring)
    p = subprocess.Popen(c, stdin=subprocess.PIPE, shell=expand)
    pipe = p.stdin
    val = pipe.write(stdin)
    pipe.close()
    if p.wait():
        die('Command failed: %s' % str(c))

    return val

def p4_write_pipe(c, stdin):
    real_cmd = p4_build_cmd(c)
    return write_pipe(real_cmd, stdin)

def read_pipe(c, ignore_error=False):
    if verbose:
        sys.stderr.write('Reading pipe: %s\n' % str(c))

    expand = isinstance(c,basestring)
    p = subprocess.Popen(c, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=expand)
    (out, err) = p.communicate()
    if p.returncode != 0 and not ignore_error:
        die('Command failed: %s\nError: %s' % (str(c), err))
    return out

def p4_read_pipe(c, ignore_error=False):
    real_cmd = p4_build_cmd(c)
    return read_pipe(real_cmd, ignore_error)

def read_pipe_lines(c):
    if verbose:
        sys.stderr.write('Reading pipe: %s\n' % str(c))

    expand = isinstance(c, basestring)
    p = subprocess.Popen(c, stdout=subprocess.PIPE, shell=expand)
    pipe = p.stdout
    val = pipe.readlines()
    if pipe.close() or p.wait():
        die('Command failed: %s' % str(c))

    return val

def p4_read_pipe_lines(c):
    """Specifically invoke p4 on the command supplied. """
    real_cmd = p4_build_cmd(c)
    return read_pipe_lines(real_cmd)

def p4_has_command(cmd):
    """Ask p4 for help on this command.  If it returns an error, the
       command does not exist in this version of p4."""
    real_cmd = p4_build_cmd(["help", cmd])
    p = subprocess.Popen(real_cmd, stdout=subprocess.PIPE,
                                   stderr=subprocess.PIPE)
    p.communicate()
    return p.returncode == 0

def p4_has_move_command():
    """See if the move command exists, that it supports -k, and that
       it has not been administratively disabled.  The arguments
       must be correct, but the filenames do not have to exist.  Use
       ones with wildcards so even if they exist, it will fail."""

    if not p4_has_command("move"):
        return False
    cmd = p4_build_cmd(["move", "-k", "@from", "@to"])
    p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    (out, err) = p.communicate()
    # return code will be 1 in either case
    if err.find("Invalid option") >= 0:
        return False
    if err.find("disabled") >= 0:
        return False
    # assume it failed because @... was invalid changelist
    return True

def system(cmd, ignore_error=False):
    expand = isinstance(cmd,basestring)
    if verbose:
        sys.stderr.write("executing %s\n" % str(cmd))
    retcode = subprocess.call(cmd, shell=expand)
    if retcode and not ignore_error:
        raise CalledProcessError(retcode, cmd)

    return retcode

def p4_system(cmd):
    """Specifically invoke p4 as the system command. """
    real_cmd = p4_build_cmd(cmd)
    expand = isinstance(real_cmd, basestring)
    retcode = subprocess.call(real_cmd, shell=expand)
    if retcode:
        raise CalledProcessError(retcode, real_cmd)

_p4_version_string = None
def p4_version_string():
    """Read the version string, showing just the last line, which
       hopefully is the interesting version bit.

       $ p4 -V
       Perforce - The Fast Software Configuration Management System.
       Copyright 1995-2011 Perforce Software.  All rights reserved.
       Rev. P4/NTX86/2011.1/393975 (2011/12/16).
    """
    global _p4_version_string
    if not _p4_version_string:
        a = p4_read_pipe_lines(["-V"])
        _p4_version_string = a[-1].rstrip()
    return _p4_version_string

def p4_integrate(src, dest):
    p4_system(["integrate", "-Dt", wildcard_encode(src), wildcard_encode(dest)])

def p4_sync(f, *options):
    p4_system(["sync"] + list(options) + [wildcard_encode(f)])

def p4_add(f):
    # forcibly add file names with wildcards
    if wildcard_present(f):
        p4_system(["add", "-f", f])
    else:
        p4_system(["add", f])

def p4_delete(f):
    p4_system(["delete", wildcard_encode(f)])

def p4_edit(f, *options):
    p4_system(["edit"] + list(options) + [wildcard_encode(f)])

def p4_revert(f):
    p4_system(["revert", wildcard_encode(f)])

def p4_reopen(type, f):
    p4_system(["reopen", "-t", type, wildcard_encode(f)])

def p4_move(src, dest):
    p4_system(["move", "-k", wildcard_encode(src), wildcard_encode(dest)])

def p4_last_change():
    results = p4CmdList(["changes", "-m", "1"])
    return int(results[0]['change'])

def p4_describe(change):
    """Make sure it returns a valid result by checking for
       the presence of field "time".  Return a dict of the
       results."""

    ds = p4CmdList(["describe", "-s", str(change)])
    if len(ds) != 1:
        die("p4 describe -s %d did not return 1 result: %s" % (change, str(ds)))

    d = ds[0]

    if "p4ExitCode" in d:
        die("p4 describe -s %d exited with %d: %s" % (change, d["p4ExitCode"],
                                                      str(d)))
    if "code" in d:
        if d["code"] == "error":
            die("p4 describe -s %d returned error code: %s" % (change, str(d)))

    if "time" not in d:
        die("p4 describe -s %d returned no \"time\": %s" % (change, str(d)))

    return d

#
# Canonicalize the p4 type and return a tuple of the
# base type, plus any modifiers.  See "p4 help filetypes"
# for a list and explanation.
#
def split_p4_type(p4type):

    p4_filetypes_historical = {
        "ctempobj": "binary+Sw",
        "ctext": "text+C",
        "cxtext": "text+Cx",
        "ktext": "text+k",
        "kxtext": "text+kx",
        "ltext": "text+F",
        "tempobj": "binary+FSw",
        "ubinary": "binary+F",
        "uresource": "resource+F",
        "uxbinary": "binary+Fx",
        "xbinary": "binary+x",
        "xltext": "text+Fx",
        "xtempobj": "binary+Swx",
        "xtext": "text+x",
        "xunicode": "unicode+x",
        "xutf16": "utf16+x",
    }
    if p4type in p4_filetypes_historical:
        p4type = p4_filetypes_historical[p4type]
    mods = ""
    s = p4type.split("+")
    base = s[0]
    mods = ""
    if len(s) > 1:
        mods = s[1]
    return (base, mods)

#
# return the raw p4 type of a file (text, text+ko, etc)
#
def p4_type(f):
    results = p4CmdList(["fstat", "-T", "headType", wildcard_encode(f)])
    return results[0]['headType']

#
# Given a type base and modifier, return a regexp matching
# the keywords that can be expanded in the file
#
def p4_keywords_regexp_for_type(base, type_mods):
    if base in ("text", "unicode", "binary"):
        kwords = None
        if "ko" in type_mods:
            kwords = 'Id|Header'
        elif "k" in type_mods:
            kwords = 'Id|Header|Author|Date|DateTime|Change|File|Revision'
        else:
            return None
        pattern = r"""
            \$              # Starts with a dollar, followed by...
            (%s)            # one of the keywords, followed by...
            (:[^$\n]+)?     # possibly an old expansion, followed by...
            \$              # another dollar
            """ % kwords
        return pattern
    else:
        return None

#
# Given a file, return a regexp matching the possible
# RCS keywords that will be expanded, or None for files
# with kw expansion turned off.
#
def p4_keywords_regexp_for_file(file):
    if not os.path.exists(file):
        return None
    else:
        (type_base, type_mods) = split_p4_type(p4_type(file))
        return p4_keywords_regexp_for_type(type_base, type_mods)

def setP4ExecBit(file, mode):
    # Reopens an already open file and changes the execute bit to match
    # the execute bit setting in the passed in mode.

    p4Type = "+x"

    if not isModeExec(mode):
        p4Type = getP4OpenedType(file)
        p4Type = re.sub('^([cku]?)x(.*)', '\\1\\2', p4Type)
        p4Type = re.sub('(.*?\+.*?)x(.*?)', '\\1\\2', p4Type)
        if p4Type[-1] == "+":
            p4Type = p4Type[0:-1]

    p4_reopen(p4Type, file)

def getP4OpenedType(file):
    # Returns the perforce file type for the given file.

    result = p4_read_pipe(["opened", wildcard_encode(file)])
    match = re.match(".*\((.+)\)( \*exclusive\*)?\r?$", result)
    if match:
        return match.group(1)
    else:
        die("Could not determine file type for %s (result: '%s')" % (file, result))

# Return the set of all p4 labels
def getP4Labels(depotPaths):
    labels = set()
    if isinstance(depotPaths,basestring):
        depotPaths = [depotPaths]

    for l in p4CmdList(["labels"] + ["%s..." % p for p in depotPaths]):
        label = l['label']
        labels.add(label)

    return labels

# Return the set of all git tags
def getGitTags():
    gitTags = set()
    for line in read_pipe_lines(["git", "tag"]):
        tag = line.strip()
        gitTags.add(tag)
    return gitTags

def diffTreePattern():
    # This is a simple generator for the diff tree regex pattern. This could be
    # a class variable if this and parseDiffTreeEntry were a part of a class.
    pattern = re.compile(':(\d+) (\d+) (\w+) (\w+) ([A-Z])(\d+)?\t(.*?)((\t(.*))|$)')
    while True:
        yield pattern

def parseDiffTreeEntry(entry):
    """Parses a single diff tree entry into its component elements.

    See git-diff-tree(1) manpage for details about the format of the diff
    output. This method returns a dictionary with the following elements:

    src_mode - The mode of the source file
    dst_mode - The mode of the destination file
    src_sha1 - The sha1 for the source file
    dst_sha1 - The sha1 fr the destination file
    status - The one letter status of the diff (i.e. 'A', 'M', 'D', etc)
    status_score - The score for the status (applicable for 'C' and 'R'
                   statuses). This is None if there is no score.
    src - The path for the source file.
    dst - The path for the destination file. This is only present for
          copy or renames. If it is not present, this is None.

    If the pattern is not matched, None is returned."""

    match = diffTreePattern().next().match(entry)
    if match:
        return {
            'src_mode': match.group(1),
            'dst_mode': match.group(2),
            'src_sha1': match.group(3),
            'dst_sha1': match.group(4),
            'status': match.group(5),
            'status_score': match.group(6),
            'src': match.group(7),
            'dst': match.group(10)
        }
    return None

def isModeExec(mode):
    # Returns True if the given git mode represents an executable file,
    # otherwise False.
    return mode[-3:] == "755"

def isModeExecChanged(src_mode, dst_mode):
    return isModeExec(src_mode) != isModeExec(dst_mode)

def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None):

    if isinstance(cmd,basestring):
        cmd = "-G " + cmd
        expand = True
    else:
        cmd = ["-G"] + cmd
        expand = False

    cmd = p4_build_cmd(cmd)
    if verbose:
        sys.stderr.write("Opening pipe: %s\n" % str(cmd))

    # Use a temporary file to avoid deadlocks without
    # subprocess.communicate(), which would put another copy
    # of stdout into memory.
    stdin_file = None
    if stdin is not None:
        stdin_file = tempfile.TemporaryFile(prefix='p4-stdin', mode=stdin_mode)
        if isinstance(stdin,basestring):
            stdin_file.write(stdin)
        else:
            for i in stdin:
                stdin_file.write(i + '\n')
        stdin_file.flush()
        stdin_file.seek(0)

    p4 = subprocess.Popen(cmd,
                          shell=expand,
                          stdin=stdin_file,
                          stdout=subprocess.PIPE)

    result = []
    try:
        while True:
            entry = marshal.load(p4.stdout)
            if cb is not None:
                cb(entry)
            else:
                result.append(entry)
    except EOFError:
        pass
    exitCode = p4.wait()
    if exitCode != 0:
        entry = {}
        entry["p4ExitCode"] = exitCode
        result.append(entry)

    return result

def p4Cmd(cmd):
    list = p4CmdList(cmd)
    result = {}
    for entry in list:
        result.update(entry)
    return result;

def p4Where(depotPath):
    if not depotPath.endswith("/"):
        depotPath += "/"
    depotPathLong = depotPath + "..."
    outputList = p4CmdList(["where", depotPathLong])
    output = None
    for entry in outputList:
        if "depotFile" in entry:
            # Search for the base client side depot path, as long as it starts with the branch's P4 path.
            # The base path always ends with "/...".
            if entry["depotFile"].find(depotPath) == 0 and entry["depotFile"][-4:] == "/...":
                output = entry
                break
        elif "data" in entry:
            data = entry.get("data")
            space = data.find(" ")
            if data[:space] == depotPath:
                output = entry
                break
    if output == None:
        return ""
    if output["code"] == "error":
        return ""
    clientPath = ""
    if "path" in output:
        clientPath = output.get("path")
    elif "data" in output:
        data = output.get("data")
        lastSpace = data.rfind(" ")
        clientPath = data[lastSpace + 1:]

    if clientPath.endswith("..."):
        clientPath = clientPath[:-3]
    return clientPath

def currentGitBranch():
    retcode = system(["git", "symbolic-ref", "-q", "HEAD"], ignore_error=True)
    if retcode != 0:
        # on a detached head
        return None
    else:
        return read_pipe(["git", "name-rev", "HEAD"]).split(" ")[1].strip()

def isValidGitDir(path):
    if (os.path.exists(path + "/HEAD")
        and os.path.exists(path + "/refs") and os.path.exists(path + "/objects")):
        return True;
    return False

def parseRevision(ref):
    return read_pipe("git rev-parse %s" % ref).strip()

def branchExists(ref):
    rev = read_pipe(["git", "rev-parse", "-q", "--verify", ref],
                     ignore_error=True)
    return len(rev) > 0

def extractLogMessageFromGitCommit(commit):
    logMessage = ""

    ## fixme: title is first line of commit, not 1st paragraph.
    foundTitle = False
    for log in read_pipe_lines("git cat-file commit %s" % commit):
       if not foundTitle:
           if len(log) == 1:
               foundTitle = True
           continue

       logMessage += log
    return logMessage

def extractSettingsGitLog(log):
    values = {}
    for line in log.split("\n"):
        line = line.strip()
        m = re.search (r"^ *\[git-p4: (.*)\]$", line)
        if not m:
            continue

        assignments = m.group(1).split (':')
        for a in assignments:
            vals = a.split ('=')
            key = vals[0].strip()
            val = ('='.join (vals[1:])).strip()
            if val.endswith ('\"') and val.startswith('"'):
                val = val[1:-1]

            values[key] = val

    paths = values.get("depot-paths")
    if not paths:
        paths = values.get("depot-path")
    if paths:
        values['depot-paths'] = paths.split(',')
    return values

def gitBranchExists(branch):
    proc = subprocess.Popen(["git", "rev-parse", branch],
                            stderr=subprocess.PIPE, stdout=subprocess.PIPE);
    return proc.wait() == 0;

_gitConfig = {}

def gitConfig(key, typeSpecifier=None):
    if not _gitConfig.has_key(key):
        cmd = [ "git", "config" ]
        if typeSpecifier:
            cmd += [ typeSpecifier ]
        cmd += [ key ]
        s = read_pipe(cmd, ignore_error=True)
        _gitConfig[key] = s.strip()
    return _gitConfig[key]

def gitConfigBool(key):
    """Return a bool, using git config --bool.  It is True only if the
       variable is set to true, and False if set to false or not present
       in the config."""

    if not _gitConfig.has_key(key):
        _gitConfig[key] = gitConfig(key, '--bool') == "true"
    return _gitConfig[key]

def gitConfigInt(key):
    if not _gitConfig.has_key(key):
        cmd = [ "git", "config", "--int", key ]
        s = read_pipe(cmd, ignore_error=True)
        v = s.strip()
        try:
            _gitConfig[key] = int(gitConfig(key, '--int'))
        except ValueError:
            _gitConfig[key] = None
    return _gitConfig[key]

def gitConfigList(key):
    if not _gitConfig.has_key(key):
        s = read_pipe(["git", "config", "--get-all", key], ignore_error=True)
        _gitConfig[key] = s.strip().split(os.linesep)
        if _gitConfig[key] == ['']:
            _gitConfig[key] = []
    return _gitConfig[key]

def p4BranchesInGit(branchesAreInRemotes=True):
    """Find all the branches whose names start with "p4/", looking
       in remotes or heads as specified by the argument.  Return
       a dictionary of { branch: revision } for each one found.
       The branch names are the short names, without any
       "p4/" prefix."""

    branches = {}

    cmdline = "git rev-parse --symbolic "
    if branchesAreInRemotes:
        cmdline += "--remotes"
    else:
        cmdline += "--branches"

    for line in read_pipe_lines(cmdline):
        line = line.strip()

        # only import to p4/
        if not line.startswith('p4/'):
            continue
        # special symbolic ref to p4/master
        if line == "p4/HEAD":
            continue

        # strip off p4/ prefix
        branch = line[len("p4/"):]

        branches[branch] = parseRevision(line)

    return branches

def branch_exists(branch):
    """Make sure that the given ref name really exists."""

    cmd = [ "git", "rev-parse", "--symbolic", "--verify", branch ]
    p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    out, _ = p.communicate()
    if p.returncode:
        return False
    # expect exactly one line of output: the branch name
    return out.rstrip() == branch

def findUpstreamBranchPoint(head = "HEAD"):
    branches = p4BranchesInGit()
    # map from depot-path to branch name
    branchByDepotPath = {}
    for branch in branches.keys():
        tip = branches[branch]
        log = extractLogMessageFromGitCommit(tip)
        settings = extractSettingsGitLog(log)
        if settings.has_key("depot-paths"):
            paths = ",".join(settings["depot-paths"])
            branchByDepotPath[paths] = "remotes/p4/" + branch

    settings = None
    parent = 0
    while parent < 65535:
        commit = head + "~%s" % parent
        log = extractLogMessageFromGitCommit(commit)
        settings = extractSettingsGitLog(log)
        if settings.has_key("depot-paths"):
            paths = ",".join(settings["depot-paths"])
            if branchByDepotPath.has_key(paths):
                return [branchByDepotPath[paths], settings]

        parent = parent + 1

    return ["", settings]

def createOrUpdateBranchesFromOrigin(localRefPrefix = "refs/remotes/p4/", silent=True):
    if not silent:
        print ("Creating/updating branch(es) in %s based on origin branch(es)"
               % localRefPrefix)

    originPrefix = "origin/p4/"

    for line in read_pipe_lines("git rev-parse --symbolic --remotes"):
        line = line.strip()
        if (not line.startswith(originPrefix)) or line.endswith("HEAD"):
            continue

        headName = line[len(originPrefix):]
        remoteHead = localRefPrefix + headName
        originHead = line

        original = extractSettingsGitLog(extractLogMessageFromGitCommit(originHead))
        if (not original.has_key('depot-paths')
            or not original.has_key('change')):
            continue

        update = False
        if not gitBranchExists(remoteHead):
            if verbose:
                print "creating %s" % remoteHead
            update = True
        else:
            settings = extractSettingsGitLog(extractLogMessageFromGitCommit(remoteHead))
            if settings.has_key('change') > 0:
                if settings['depot-paths'] == original['depot-paths']:
                    originP4Change = int(original['change'])
                    p4Change = int(settings['change'])
                    if originP4Change > p4Change:
                        print ("%s (%s) is newer than %s (%s). "
                               "Updating p4 branch from origin."
                               % (originHead, originP4Change,
                                  remoteHead, p4Change))
                        update = True
                else:
                    print ("Ignoring: %s was imported from %s while "
                           "%s was imported from %s"
                           % (originHead, ','.join(original['depot-paths']),
                              remoteHead, ','.join(settings['depot-paths'])))

        if update:
            system("git update-ref %s %s" % (remoteHead, originHead))

def originP4BranchesExist():
        return gitBranchExists("origin") or gitBranchExists("origin/p4") or gitBranchExists("origin/p4/master")


def p4ParseNumericChangeRange(parts):
    changeStart = int(parts[0][1:])
    if parts[1] == '#head':
        changeEnd = p4_last_change()
    else:
        changeEnd = int(parts[1])

    return (changeStart, changeEnd)

def chooseBlockSize(blockSize):
    if blockSize:
        return blockSize
    else:
        return defaultBlockSize

def p4ChangesForPaths(depotPaths, changeRange, requestedBlockSize):
    assert depotPaths

    # Parse the change range into start and end. Try to find integer
    # revision ranges as these can be broken up into blocks to avoid
    # hitting server-side limits (maxrows, maxscanresults). But if
    # that doesn't work, fall back to using the raw revision specifier
    # strings, without using block mode.

    if changeRange is None or changeRange == '':
        changeStart = 1
        changeEnd = p4_last_change()
        block_size = chooseBlockSize(requestedBlockSize)
    else:
        parts = changeRange.split(',')
        assert len(parts) == 2
        try:
            (changeStart, changeEnd) = p4ParseNumericChangeRange(parts)
            block_size = chooseBlockSize(requestedBlockSize)
        except:
            changeStart = parts[0][1:]
            changeEnd = parts[1]
            if requestedBlockSize:
                die("cannot use --changes-block-size with non-numeric revisions")
            block_size = None

    changes = []

    # Retrieve changes a block at a time, to prevent running
    # into a MaxResults/MaxScanRows error from the server.

    while True:
        cmd = ['changes']

        if block_size:
            end = min(changeEnd, changeStart + block_size)
            revisionRange = "%d,%d" % (changeStart, end)
        else:
            revisionRange = "%s,%s" % (changeStart, changeEnd)

        for p in depotPaths:
            cmd += ["%s...@%s" % (p, revisionRange)]

        # Insert changes in chronological order
        for line in reversed(p4_read_pipe_lines(cmd)):
            changes.append(int(line.split(" ")[1]))

        if not block_size:
            break

        if end >= changeEnd:
            break

        changeStart = end + 1

    changes = sorted(changes)
    return changes

def p4PathStartsWith(path, prefix):
    # This method tries to remedy a potential mixed-case issue:
    #
    # If UserA adds  //depot/DirA/file1
    # and UserB adds //depot/dira/file2
    #
    # we may or may not have a problem. If you have core.ignorecase=true,
    # we treat DirA and dira as the same directory
    if gitConfigBool("core.ignorecase"):
        return path.lower().startswith(prefix.lower())
    return path.startswith(prefix)

def getClientSpec():
    """Look at the p4 client spec, create a View() object that contains
       all the mappings, and return it."""

    specList = p4CmdList("client -o")
    if len(specList) != 1:
        die('Output from "client -o" is %d lines, expecting 1' %
            len(specList))

    # dictionary of all client parameters
    entry = specList[0]

    # the //client/ name
    client_name = entry["Client"]

    # just the keys that start with "View"
    view_keys = [ k for k in entry.keys() if k.startswith("View") ]

    # hold this new View
    view = View(client_name)

    # append the lines, in order, to the view
    for view_num in range(len(view_keys)):
        k = "View%d" % view_num
        if k not in view_keys:
            die("Expected view key %s missing" % k)
        view.append(entry[k])

    return view

def getClientRoot():
    """Grab the client directory."""

    output = p4CmdList("client -o")
    if len(output) != 1:
        die('Output from "client -o" is %d lines, expecting 1' % len(output))

    entry = output[0]
    if "Root" not in entry:
        die('Client has no "Root"')

    return entry["Root"]

#
# P4 wildcards are not allowed in filenames.  P4 complains
# if you simply add them, but you can force it with "-f", in
# which case it translates them into %xx encoding internally.
#
def wildcard_decode(path):
    # Search for and fix just these four characters.  Do % last so
    # that fixing it does not inadvertently create new %-escapes.
    # Cannot have * in a filename in windows; untested as to
    # what p4 would do in such a case.
    if not platform.system() == "Windows":
        path = path.replace("%2A", "*")
    path = path.replace("%23", "#") \
               .replace("%40", "@") \
               .replace("%25", "%")
    return path

def wildcard_encode(path):
    # do % first to avoid double-encoding the %s introduced here
    path = path.replace("%", "%25") \
               .replace("*", "%2A") \
               .replace("#", "%23") \
               .replace("@", "%40")
    return path

def wildcard_present(path):
    m = re.search("[*#@%]", path)
    return m is not None

class LargeFileSystem(object):
    """Base class for large file system support."""

    def __init__(self, writeToGitStream):
        self.largeFiles = set()
        self.writeToGitStream = writeToGitStream

    def generatePointer(self, cloneDestination, contentFile):
        """Return the content of a pointer file that is stored in Git instead of
           the actual content."""
        assert False, "Method 'generatePointer' required in " + self.__class__.__name__

    def pushFile(self, localLargeFile):
        """Push the actual content which is not stored in the Git repository to
           a server."""
        assert False, "Method 'pushFile' required in " + self.__class__.__name__

    def hasLargeFileExtension(self, relPath):
        return reduce(
            lambda a, b: a or b,
            [relPath.endswith('.' + e) for e in gitConfigList('git-p4.largeFileExtensions')],
            False
        )

    def generateTempFile(self, contents):
        contentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=False)
        for d in contents:
            contentFile.write(d)
        contentFile.close()
        return contentFile.name

    def exceedsLargeFileThreshold(self, relPath, contents):
        if gitConfigInt('git-p4.largeFileThreshold'):
            contentsSize = sum(len(d) for d in contents)
            if contentsSize > gitConfigInt('git-p4.largeFileThreshold'):
                return True
        if gitConfigInt('git-p4.largeFileCompressedThreshold'):
            contentsSize = sum(len(d) for d in contents)
            if contentsSize <= gitConfigInt('git-p4.largeFileCompressedThreshold'):
                return False
            contentTempFile = self.generateTempFile(contents)
            compressedContentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=False)
            zf = zipfile.ZipFile(compressedContentFile.name, mode='w')
            zf.write(contentTempFile, compress_type=zipfile.ZIP_DEFLATED)
            zf.close()
            compressedContentsSize = zf.infolist()[0].compress_size
            os.remove(contentTempFile)
            os.remove(compressedContentFile.name)
            if compressedContentsSize > gitConfigInt('git-p4.largeFileCompressedThreshold'):
                return True
        return False

    def addLargeFile(self, relPath):
        self.largeFiles.add(relPath)

    def removeLargeFile(self, relPath):
        self.largeFiles.remove(relPath)

    def isLargeFile(self, relPath):
        return relPath in self.largeFiles

    def processContent(self, git_mode, relPath, contents):
        """Processes the content of git fast import. This method decides if a
           file is stored in the large file system and handles all necessary
           steps."""
        if self.exceedsLargeFileThreshold(relPath, contents) or self.hasLargeFileExtension(relPath):
            contentTempFile = self.generateTempFile(contents)
            (git_mode, contents, localLargeFile) = self.generatePointer(contentTempFile)

            # Move temp file to final location in large file system
            largeFileDir = os.path.dirname(localLargeFile)
            if not os.path.isdir(largeFileDir):
                os.makedirs(largeFileDir)
            shutil.move(contentTempFile, localLargeFile)
            self.addLargeFile(relPath)
            if gitConfigBool('git-p4.largeFilePush'):
                self.pushFile(localLargeFile)
            if verbose:
                sys.stderr.write("%s moved to large file system (%s)\n" % (relPath, localLargeFile))
        return (git_mode, contents)

class MockLFS(LargeFileSystem):
    """Mock large file system for testing."""

    def generatePointer(self, contentFile):
        """The pointer content is the original content prefixed with "pointer-".
           The local filename of the large file storage is derived from the file content.
           """
        with open(contentFile, 'r') as f:
            content = next(f)
            gitMode = '100644'
            pointerContents = 'pointer-' + content
            localLargeFile = os.path.join(os.getcwd(), '.git', 'mock-storage', 'local', content[:-1])
            return (gitMode, pointerContents, localLargeFile)

    def pushFile(self, localLargeFile):
        """The remote filename of the large file storage is the same as the local
           one but in a different directory.
           """
        remotePath = os.path.join(os.path.dirname(localLargeFile), '..', 'remote')
        if not os.path.exists(remotePath):
            os.makedirs(remotePath)
        shutil.copyfile(localLargeFile, os.path.join(remotePath, os.path.basename(localLargeFile)))

class GitLFS(LargeFileSystem):
    """Git LFS as backend for the git-p4 large file system.
       See https://git-lfs.github.com/ for details."""

    def __init__(self, *args):
        LargeFileSystem.__init__(self, *args)
        self.baseGitAttributes = []

    def generatePointer(self, contentFile):
        """Generate a Git LFS pointer for the content. Return LFS Pointer file
           mode and content which is stored in the Git repository instead of
           the actual content. Return also the new location of the actual
           content.
           """
        pointerProcess = subprocess.Popen(
            ['git', 'lfs', 'pointer', '--file=' + contentFile],
            stdout=subprocess.PIPE
        )
        pointerFile = pointerProcess.stdout.read()
        if pointerProcess.wait():
            os.remove(contentFile)
            die('git-lfs pointer command failed. Did you install the extension?')

        # Git LFS removed the preamble in the output of the 'pointer' command
        # starting from version 1.2.0. Check for the preamble here to support
        # earlier versions.
        # c.f. https://github.com/github/git-lfs/commit/da2935d9a739592bc775c98d8ef4df9c72ea3b43
        if pointerFile.startswith('Git LFS pointer for'):
            pointerFile = re.sub(r'Git LFS pointer for.*\n\n', '', pointerFile)

        oid = re.search(r'^oid \w+:(\w+)', pointerFile, re.MULTILINE).group(1)
        localLargeFile = os.path.join(
            os.getcwd(),
            '.git', 'lfs', 'objects', oid[:2], oid[2:4],
            oid,
        )
        # LFS Spec states that pointer files should not have the executable bit set.
        gitMode = '100644'
        return (gitMode, pointerFile, localLargeFile)

    def pushFile(self, localLargeFile):
        uploadProcess = subprocess.Popen(
            ['git', 'lfs', 'push', '--object-id', 'origin', os.path.basename(localLargeFile)]
        )
        if uploadProcess.wait():
            die('git-lfs push command failed. Did you define a remote?')

    def generateGitAttributes(self):
        return (
            self.baseGitAttributes +
            [
                '\n',
                '#\n',
                '# Git LFS (see https://git-lfs.github.com/)\n',
                '#\n',
            ] +
            ['*.' + f.replace(' ', '[[:space:]]') + ' filter=lfs -text\n'
                for f in sorted(gitConfigList('git-p4.largeFileExtensions'))
            ] +
            ['/' + f.replace(' ', '[[:space:]]') + ' filter=lfs -text\n'
                for f in sorted(self.largeFiles) if not self.hasLargeFileExtension(f)
            ]
        )

    def addLargeFile(self, relPath):
        LargeFileSystem.addLargeFile(self, relPath)
        self.writeToGitStream('100644', '.gitattributes', self.generateGitAttributes())

    def removeLargeFile(self, relPath):
        LargeFileSystem.removeLargeFile(self, relPath)
        self.writeToGitStream('100644', '.gitattributes', self.generateGitAttributes())

    def processContent(self, git_mode, relPath, contents):
        if relPath == '.gitattributes':
            self.baseGitAttributes = contents
            return (git_mode, self.generateGitAttributes())
        else:
            return LargeFileSystem.processContent(self, git_mode, relPath, contents)

class Command:
    def __init__(self):
        self.usage = "usage: %prog [options]"
        self.needsGit = True
        self.verbose = False

class P4UserMap:
    def __init__(self):
        self.userMapFromPerforceServer = False
        self.myP4UserId = None

    def p4UserId(self):
        if self.myP4UserId:
            return self.myP4UserId

        results = p4CmdList("user -o")
        for r in results:
            if r.has_key('User'):
                self.myP4UserId = r['User']
                return r['User']
        die("Could not find your p4 user id")

    def p4UserIsMe(self, p4User):
        # return True if the given p4 user is actually me
        me = self.p4UserId()
        if not p4User or p4User != me:
            return False
        else:
            return True

    def getUserCacheFilename(self):
        home = os.environ.get("HOME", os.environ.get("USERPROFILE"))
        return home + "/.gitp4-usercache.txt"

    def getUserMapFromPerforceServer(self):
        if self.userMapFromPerforceServer:
            return
        self.users = {}
        self.emails = {}

        for output in p4CmdList("users"):
            if not output.has_key("User"):
                continue
            self.users[output["User"]] = output["FullName"] + " <" + output["Email"] + ">"
            self.emails[output["Email"]] = output["User"]

        mapUserConfigRegex = re.compile(r"^\s*(\S+)\s*=\s*(.+)\s*<(\S+)>\s*$", re.VERBOSE)
        for mapUserConfig in gitConfigList("git-p4.mapUser"):
            mapUser = mapUserConfigRegex.findall(mapUserConfig)
            if mapUser and len(mapUser[0]) == 3:
                user = mapUser[0][0]
                fullname = mapUser[0][1]
                email = mapUser[0][2]
                self.users[user] = fullname + " <" + email + ">"
                self.emails[email] = user

        s = ''
        for (key, val) in self.users.items():
            s += "%s\t%s\n" % (key.expandtabs(1), val.expandtabs(1))

        open(self.getUserCacheFilename(), "wb").write(s)
        self.userMapFromPerforceServer = True

    def loadUserMapFromCache(self):
        self.users = {}
        self.userMapFromPerforceServer = False
        try:
            cache = open(self.getUserCacheFilename(), "rb")
            lines = cache.readlines()
            cache.close()
            for line in lines:
                entry = line.strip().split("\t")
                self.users[entry[0]] = entry[1]
        except IOError:
            self.getUserMapFromPerforceServer()

class P4Debug(Command):
    def __init__(self):
        Command.__init__(self)
        self.options = []
        self.description = "A tool to debug the output of p4 -G."
        self.needsGit = False

    def run(self, args):
        j = 0
        for output in p4CmdList(args):
            print 'Element: %d' % j
            j += 1
            print output
        return True

class P4RollBack(Command):
    def __init__(self):
        Command.__init__(self)
        self.options = [
            optparse.make_option("--local", dest="rollbackLocalBranches", action="store_true")
        ]
        self.description = "A tool to debug the multi-branch import. Don't use :)"
        self.rollbackLocalBranches = False

    def run(self, args):
        if len(args) != 1:
            return False
        maxChange = int(args[0])

        if "p4ExitCode" in p4Cmd("changes -m 1"):
            die("Problems executing p4");

        if self.rollbackLocalBranches:
            refPrefix = "refs/heads/"
            lines = read_pipe_lines("git rev-parse --symbolic --branches")
        else:
            refPrefix = "refs/remotes/"
            lines = read_pipe_lines("git rev-parse --symbolic --remotes")

        for line in lines:
            if self.rollbackLocalBranches or (line.startswith("p4/") and line != "p4/HEAD\n"):
                line = line.strip()
                ref = refPrefix + line
                log = extractLogMessageFromGitCommit(ref)
                settings = extractSettingsGitLog(log)

                depotPaths = settings['depot-paths']
                change = settings['change']

                changed = False

                if len(p4Cmd("changes -m 1 "  + ' '.join (['%s...@%s' % (p, maxChange)
                                                           for p in depotPaths]))) == 0:
                    print "Branch %s did not exist at change %s, deleting." % (ref, maxChange)
                    system("git update-ref -d %s `git rev-parse %s`" % (ref, ref))
                    continue

                while change and int(change) > maxChange:
                    changed = True
                    if self.verbose:
                        print "%s is at %s ; rewinding towards %s" % (ref, change, maxChange)
                    system("git update-ref %s \"%s^\"" % (ref, ref))
                    log = extractLogMessageFromGitCommit(ref)
                    settings =  extractSettingsGitLog(log)


                    depotPaths = settings['depot-paths']
                    change = settings['change']

                if changed:
                    print "%s rewound to %s" % (ref, change)

        return True

class P4Submit(Command, P4UserMap):

    conflict_behavior_choices = ("ask", "skip", "quit")

    def __init__(self):
        Command.__init__(self)
        P4UserMap.__init__(self)
        self.options = [
                optparse.make_option("--origin", dest="origin"),
                optparse.make_option("-M", dest="detectRenames", action="store_true"),
                # preserve the user, requires relevant p4 permissions
                optparse.make_option("--preserve-user", dest="preserveUser", action="store_true"),
                optparse.make_option("--export-labels", dest="exportLabels", action="store_true"),
                optparse.make_option("--dry-run", "-n", dest="dry_run", action="store_true"),
                optparse.make_option("--prepare-p4-only", dest="prepare_p4_only", action="store_true"),
                optparse.make_option("--conflict", dest="conflict_behavior",
                                     choices=self.conflict_behavior_choices),
                optparse.make_option("--branch", dest="branch"),
        ]
        self.description = "Submit changes from git to the perforce depot."
        self.usage += " [name of git branch to submit into perforce depot]"
        self.origin = ""
        self.detectRenames = False
        self.preserveUser = gitConfigBool("git-p4.preserveUser")
        self.dry_run = False
        self.prepare_p4_only = False
        self.conflict_behavior = None
        self.isWindows = (platform.system() == "Windows")
        self.exportLabels = False
        self.p4HasMoveCommand = p4_has_move_command()
        self.branch = None

        if gitConfig('git-p4.largeFileSystem'):
            die("Large file system not supported for git-p4 submit command. Please remove it from config.")

    def check(self):
        if len(p4CmdList("opened ...")) > 0:
            die("You have files opened with perforce! Close them before starting the sync.")

    def separate_jobs_from_description(self, message):
        """Extract and return a possible Jobs field in the commit
           message.  It goes into a separate section in the p4 change
           specification.

           A jobs line starts with "Jobs:" and looks like a new field
           in a form.  Values are white-space separated on the same
           line or on following lines that start with a tab.

           This does not parse and extract the full git commit message
           like a p4 form.  It just sees the Jobs: line as a marker
           to pass everything from then on directly into the p4 form,
           but outside the description section.

           Return a tuple (stripped log message, jobs string)."""

        m = re.search(r'^Jobs:', message, re.MULTILINE)
        if m is None:
            return (message, None)

        jobtext = message[m.start():]
        stripped_message = message[:m.start()].rstrip()
        return (stripped_message, jobtext)

    def prepareLogMessage(self, template, message, jobs):
        """Edits the template returned from "p4 change -o" to insert
           the message in the Description field, and the jobs text in
           the Jobs field."""
        result = ""

        inDescriptionSection = False

        for line in template.split("\n"):
            if line.startswith("#"):
                result += line + "\n"
                continue

            if inDescriptionSection:
                if line.startswith("Files:") or line.startswith("Jobs:"):
                    inDescriptionSection = False
                    # insert Jobs section
                    if jobs:
                        result += jobs + "\n"
                else:
                    continue
            else:
                if line.startswith("Description:"):
                    inDescriptionSection = True
                    line += "\n"
                    for messageLine in message.split("\n"):
                        line += "\t" + messageLine + "\n"

            result += line + "\n"

        return result

    def patchRCSKeywords(self, file, pattern):
        # Attempt to zap the RCS keywords in a p4 controlled file matching the given pattern
        (handle, outFileName) = tempfile.mkstemp(dir='.')
        try:
            outFile = os.fdopen(handle, "w+")
            inFile = open(file, "r")
            regexp = re.compile(pattern, re.VERBOSE)
            for line in inFile.readlines():
                line = regexp.sub(r'$\1$', line)
                outFile.write(line)
            inFile.close()
            outFile.close()
            # Forcibly overwrite the original file
            os.unlink(file)
            shutil.move(outFileName, file)
        except:
            # cleanup our temporary file
            os.unlink(outFileName)
            print "Failed to strip RCS keywords in %s" % file
            raise

        print "Patched up RCS keywords in %s" % file

    def p4UserForCommit(self,id):
        # Return the tuple (perforce user,git email) for a given git commit id
        self.getUserMapFromPerforceServer()
        gitEmail = read_pipe(["git", "log", "--max-count=1",
                              "--format=%ae", id])
        gitEmail = gitEmail.strip()
        if not self.emails.has_key(gitEmail):
            return (None,gitEmail)
        else:
            return (self.emails[gitEmail],gitEmail)

    def checkValidP4Users(self,commits):
        # check if any git authors cannot be mapped to p4 users
        for id in commits:
            (user,email) = self.p4UserForCommit(id)
            if not user:
                msg = "Cannot find p4 user for email %s in commit %s." % (email, id)
                if gitConfigBool("git-p4.allowMissingP4Users"):
                    print "%s" % msg
                else:
                    die("Error: %s\nSet git-p4.allowMissingP4Users to true to allow this." % msg)

    def lastP4Changelist(self):
        # Get back the last changelist number submitted in this client spec. This
        # then gets used to patch up the username in the change. If the same
        # client spec is being used by multiple processes then this might go
        # wrong.
        results = p4CmdList("client -o")        # find the current client
        client = None
        for r in results:
            if r.has_key('Client'):
                client = r['Client']
                break
        if not client:
            die("could not get client spec")
        results = p4CmdList(["changes", "-c", client, "-m", "1"])
        for r in results:
            if r.has_key('change'):
                return r['change']
        die("Could not get changelist number for last submit - cannot patch up user details")

    def modifyChangelistUser(self, changelist, newUser):
        # fixup the user field of a changelist after it has been submitted.
        changes = p4CmdList("change -o %s" % changelist)
        if len(changes) != 1:
            die("Bad output from p4 change modifying %s to user %s" %
                (changelist, newUser))

        c = changes[0]
        if c['User'] == newUser: return   # nothing to do
        c['User'] = newUser
        input = marshal.dumps(c)

        result = p4CmdList("change -f -i", stdin=input)
        for r in …