diff --git a/integrations/perforce/git_p4.py b/integrations/perforce/git_p4.py
new file mode 100644
index 00000000..06a3cc61
--- /dev/null
+++ b/integrations/perforce/git_p4.py
@@ -0,0 +1,3287 @@
+#!/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
+
+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_\-.]+$'
+
+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 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, shell=expand)
+    pipe = p.stdout
+    val = pipe.read()
+    if p.wait() and not ignore_error:
+        die('Command failed: %s' % str(c))
+
+    return val
+
+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):
+    expand = isinstance(cmd,basestring)
+    if verbose:
+        sys.stderr.write("executing %s\n" % str(cmd))
+    retcode = subprocess.call(cmd, shell=expand)
+    if retcode:
+        raise CalledProcessError(retcode, cmd)
+
+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):
+    p4_system(["edit", 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_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(file):
+    results = p4CmdList(["fstat", "-T", "headType", file])
+    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(".*\((.+)\)\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 += "/"
+    depotPath = depotPath + "..."
+    outputList = p4CmdList(["where", depotPath])
+    output = None
+    for entry in outputList:
+        if "depotFile" in entry:
+            if entry["depotFile"] == depotPath:
+                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():
+    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):
+    if not _gitConfig.has_key(key):
+        cmd = [ "git", "config", 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):
+        cmd = [ "git", "config", "--bool", key ]
+        s = read_pipe(cmd, ignore_error=True)
+        v = s.strip()
+        _gitConfig[key] = v == "true"
+    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)
+    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 p4ChangesForPaths(depotPaths, changeRange):
+    assert depotPaths
+    cmd = ['changes']
+    for p in depotPaths:
+        cmd += ["%s...%s" % (p, changeRange)]
+    output = p4_read_pipe_lines(cmd)
+
+    changes = {}
+    for line in output:
+        changeNum = int(line.split(" ")[1])
+        changes[changeNum] = True
+
+    changelist = changes.keys()
+    changelist.sort()
+    return changelist
+
+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 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"]
+
+
+        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
+
+    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 result:
+            if r.has_key('code'):
+                if r['code'] == 'error':
+                    die("Could not modify user field of changelist %s to %s:%s" % (changelist, newUser, r['data']))
+            if r.has_key('data'):
+                print("Updated user field for changelist %s to %s" % (changelist, newUser))
+                return
+        die("Could not modify user field of changelist %s to %s" % (changelist, newUser))
+
+    def canChangeChangelists(self):
+        # check to see if we have p4 admin or super-user permissions, either of
+        # which are required to modify changelists.
+        results = p4CmdList(["protects", self.depotPath])
+        for r in results:
+            if r.has_key('perm'):
+                if r['perm'] == 'admin':
+                    return 1
+                if r['perm'] == 'super':
+                    return 1
+        return 0
+
+    def prepareSubmitTemplate(self):
+        """Run "p4 change -o" to grab a change specification template.
+           This does not use "p4 -G", as it is nice to keep the submission
+           template in original order, since a human might edit it.
+
+           Remove lines in the Files section that show changes to files
+           outside the depot path we're committing into."""
+
+        template = ""
+        inFilesSection = False
+        for line in p4_read_pipe_lines(['change', '-o']):
+            if line.endswith("\r\n"):
+                line = line[:-2] + "\n"
+            if inFilesSection:
+                if line.startswith("\t"):
+                    # path starts and ends with a tab
+                    path = line[1:]
+                    lastTab = path.rfind("\t")
+                    if lastTab != -1:
+                        path = path[:lastTab]
+                        if not p4PathStartsWith(path, self.depotPath):
+                            continue
+                else:
+                    inFilesSection = False
+            else:
+                if line.startswith("Files:"):
+                    inFilesSection = True
+
+            template += line
+
+        return template
+
+    def edit_template(self, template_file):
+        """Invoke the editor to let the user change the submission
+           message.  Return true if okay to continue with the submit."""
+
+        # if configured to skip the editing part, just submit
+        if gitConfigBool("git-p4.skipSubmitEdit"):
+            return True
+
+        # look at the modification time, to check later if the user saved
+        # the file
+        mtime = os.stat(template_file).st_mtime
+
+        # invoke the editor
+        if os.environ.has_key("P4EDITOR") and (os.environ.get("P4EDITOR") != ""):
+            editor = os.environ.get("P4EDITOR")
+        else:
+            editor = read_pipe("git var GIT_EDITOR").strip()
+        system(editor + " " + template_file)
+
+        # If the file was not saved, prompt to see if this patch should
+        # be skipped.  But skip this verification step if configured so.
+        if gitConfigBool("git-p4.skipSubmitEditCheck"):
+            return True
+
+        # modification time updated means user saved the file
+        if os.stat(template_file).st_mtime > mtime:
+            return True
+
+        while True:
+            response = raw_input("Submit template unchanged. Submit anyway? [y]es, [n]o (skip this patch) ")
+            if response == 'y':
+                return True
+            if response == 'n':
+                return False
+
+    def applyCommit(self, id):
+        """Apply one commit, return True if it succeeded."""
+
+        print "Applying", read_pipe(["git", "show", "-s",
+                                     "--format=format:%h %s", id])
+
+        (p4User, gitEmail) = self.p4UserForCommit(id)
+
+        diff = read_pipe_lines("git diff-tree -r %s \"%s^\" \"%s\"" % (self.diffOpts, id, id))
+        filesToAdd = set()
+        filesToDelete = set()
+        editedFiles = set()
+        pureRenameCopy = set()
+        filesToChangeExecBit = {}
+
+        for line in diff:
+            diff = parseDiffTreeEntry(line)
+            modifier = diff['status']
+            path = diff['src']
+            if modifier == "M":
+                p4_edit(path)
+                if isModeExecChanged(diff['src_mode'], diff['dst_mode']):
+                    filesToChangeExecBit[path] = diff['dst_mode']
+                editedFiles.add(path)
+            elif modifier == "A":
+                filesToAdd.add(path)
+                filesToChangeExecBit[path] = diff['dst_mode']
+                if path in filesToDelete:
+                    filesToDelete.remove(path)
+            elif modifier == "D":
+                filesToDelete.add(path)
+                if path in filesToAdd:
+                    filesToAdd.remove(path)
+            elif modifier == "C":
+                src, dest = diff['src'], diff['dst']
+                p4_integrate(src, dest)
+                pureRenameCopy.add(dest)
+                if diff['src_sha1'] != diff['dst_sha1']:
+                    p4_edit(dest)
+                    pureRenameCopy.discard(dest)
+                if isModeExecChanged(diff['src_mode'], diff['dst_mode']):
+                    p4_edit(dest)
+                    pureRenameCopy.discard(dest)
+                    filesToChangeExecBit[dest] = diff['dst_mode']
+                if self.isWindows:
+                    # turn off read-only attribute
+                    os.chmod(dest, stat.S_IWRITE)
+                os.unlink(dest)
+                editedFiles.add(dest)
+            elif modifier == "R":
+                src, dest = diff['src'], diff['dst']
+                if self.p4HasMoveCommand:
+                    p4_edit(src)        # src must be open before move
+                    p4_move(src, dest)  # opens for (move/delete, move/add)
+                else:
+                    p4_integrate(src, dest)
+                    if diff['src_sha1'] != diff['dst_sha1']:
+                        p4_edit(dest)
+                    else:
+                        pureRenameCopy.add(dest)
+                if isModeExecChanged(diff['src_mode'], diff['dst_mode']):
+                    if not self.p4HasMoveCommand:
+                        p4_edit(dest)   # with move: already open, writable
+                    filesToChangeExecBit[dest] = diff['dst_mode']
+                if not self.p4HasMoveCommand:
+                    if self.isWindows:
+                        os.chmod(dest, stat.S_IWRITE)
+                    os.unlink(dest)
+                    filesToDelete.add(src)
+                editedFiles.add(dest)
+            else:
+                die("unknown modifier %s for %s" % (modifier, path))
+
+        diffcmd = "git format-patch -k --stdout \"%s^\"..\"%s\"" % (id, id)
+        patchcmd = diffcmd + " | git apply "
+        tryPatchCmd = patchcmd + "--check -"
+        applyPatchCmd = patchcmd + "--check --apply -"
+        patch_succeeded = True
+
+        if os.system(tryPatchCmd) != 0:
+            fixed_rcs_keywords = False
+            patch_succeeded = False
+            print "Unfortunately applying the change failed!"
+
+            # Patch failed, maybe it's just RCS keyword woes. Look through
+            # the patch to see if that's possible.
+            if gitConfigBool("git-p4.attemptRCSCleanup"):
+                file = None
+                pattern = None
+                kwfiles = {}
+                for file in editedFiles | filesToDelete:
+                    # did this file's delta contain RCS keywords?
+                    pattern = p4_keywords_regexp_for_file(file)
+
+                    if pattern:
+                        # this file is a possibility...look for RCS keywords.
+                        regexp = re.compile(pattern, re.VERBOSE)
+                        for line in read_pipe_lines(["git", "diff", "%s^..%s" % (id, id), file]):
+                            if regexp.search(line):
+                                if verbose:
+                                    print "got keyword match on %s in %s in %s" % (pattern, line, file)
+                                kwfiles[file] = pattern
+                                break
+
+                for file in kwfiles:
+                    if verbose:
+                        print "zapping %s with %s" % (line,pattern)
+                    # File is being deleted, so not open in p4.  Must
+                    # disable the read-only bit on windows.
+                    if self.isWindows and file not in editedFiles:
+                        os.chmod(file, stat.S_IWRITE)
+                    self.patchRCSKeywords(file, kwfiles[file])
+                    fixed_rcs_keywords = True
+
+            if fixed_rcs_keywords:
+                print "Retrying the patch with RCS keywords cleaned up"
+                if os.system(tryPatchCmd) == 0:
+                    patch_succeeded = True
+
+        if not patch_succeeded:
+            for f in editedFiles:
+                p4_revert(f)
+            return False
+
+        #
+        # Apply the patch for real, and do add/delete/+x handling.
+        #
+        system(applyPatchCmd)
+
+        for f in filesToAdd:
+            p4_add(f)
+        for f in filesToDelete:
+            p4_revert(f)
+            p4_delete(f)
+
+        # Set/clear executable bits
+        for f in filesToChangeExecBit.keys():
+            mode = filesToChangeExecBit[f]
+            setP4ExecBit(f, mode)
+
+        #
+        # Build p4 change description, starting with the contents
+        # of the git commit message.
+        #
+        logMessage = extractLogMessageFromGitCommit(id)
+        logMessage = logMessage.strip()
+        (logMessage, jobs) = self.separate_jobs_from_description(logMessage)
+
+        template = self.prepareSubmitTemplate()
+        submitTemplate = self.prepareLogMessage(template, logMessage, jobs)
+
+        if self.preserveUser:
+           submitTemplate += "\n######## Actual user %s, modified after commit\n" % p4User
+
+        if self.checkAuthorship and not self.p4UserIsMe(p4User):
+            submitTemplate += "######## git author %s does not match your p4 account.\n" % gitEmail
+            submitTemplate += "######## Use option --preserve-user to modify authorship.\n"
+            submitTemplate += "######## Variable git-p4.skipUserNameCheck hides this message.\n"
+
+        separatorLine = "######## everything below this line is just the diff #######\n"
+
+        # diff
+        if os.environ.has_key("P4DIFF"):
+            del(os.environ["P4DIFF"])
+        diff = ""
+        for editedFile in editedFiles:
+            diff += p4_read_pipe(['diff', '-du',
+                                  wildcard_encode(editedFile)])
+
+        # new file diff
+        newdiff = ""
+        for newFile in filesToAdd:
+            newdiff += "==== new file ====\n"
+            newdiff += "--- /dev/null\n"
+            newdiff += "+++ %s\n" % newFile
+            f = open(newFile, "r")
+            for line in f.readlines():
+                newdiff += "+" + line
+            f.close()
+
+        # change description file: submitTemplate, separatorLine, diff, newdiff
+        (handle, fileName) = tempfile.mkstemp()
+        tmpFile = os.fdopen(handle, "w+")
+        if self.isWindows:
+            submitTemplate = submitTemplate.replace("\n", "\r\n")
+            separatorLine = separatorLine.replace("\n", "\r\n")
+            newdiff = newdiff.replace("\n", "\r\n")
+        tmpFile.write(submitTemplate + separatorLine + diff + newdiff)
+        tmpFile.close()
+
+        if self.prepare_p4_only:
+            #
+            # Leave the p4 tree prepared, and the submit template around
+            # and let the user decide what to do next
+            #
+            print
+            print "P4 workspace prepared for submission."
+            print "To submit or revert, go to client workspace"
+            print "  " + self.clientPath
+            print
+            print "To submit, use \"p4 submit\" to write a new description,"
+            print "or \"p4 submit -i %s\" to use the one prepared by" \
+                  " \"git p4\"." % fileName
+            print "You can delete the file \"%s\" when finished." % fileName
+
+            if self.preserveUser and p4User and not self.p4UserIsMe(p4User):
+                print "To preserve change ownership by user %s, you must\n" \
+                      "do \"p4 change -f <change>\" after submitting and\n" \
+                      "edit the User field."
+            if pureRenameCopy:
+                print "After submitting, renamed files must be re-synced."
+                print "Invoke \"p4 sync -f\" on each of these files:"
+                for f in pureRenameCopy:
+                    print "  " + f
+
+            print
+            print "To revert the changes, use \"p4 revert ...\", and delete"
+            print "the submit template file \"%s\"" % fileName
+            if filesToAdd:
+                print "Since the commit adds new files, they must be deleted:"
+                for f in filesToAdd:
+                    print "  " + f
+            print
+            return True
+
+        #
+        # Let the user edit the change description, then submit it.
+        #
+        if self.edit_template(fileName):
+            # read the edited message and submit
+            ret = True
+            tmpFile = open(fileName, "rb")
+            message = tmpFile.read()
+            tmpFile.close()
+            submitTemplate = message[:message.index(separatorLine)]
+            if self.isWindows:
+                submitTemplate = submitTemplate.replace("\r\n", "\n")
+            p4_write_pipe(['submit', '-i'], submitTemplate)
+
+            if self.preserveUser:
+                if p4User:
+                    # Get last changelist number. Cannot easily get it from
+                    # the submit command output as the output is
+                    # unmarshalled.
+                    changelist = self.lastP4Changelist()
+                    self.modifyChangelistUser(changelist, p4User)
+
+            # The rename/copy happened by applying a patch that created a
+            # new file.  This leaves it writable, which confuses p4.
+            for f in pureRenameCopy:
+                p4_sync(f, "-f")
+
+        else:
+            # skip this patch
+            ret = False
+            print "Submission cancelled, undoing p4 changes."
+            for f in editedFiles:
+                p4_revert(f)
+            for f in filesToAdd:
+                p4_revert(f)
+                os.remove(f)
+            for f in filesToDelete:
+                p4_revert(f)
+
+        os.remove(fileName)
+        return ret
+
+    # Export git tags as p4 labels. Create a p4 label and then tag
+    # with that.
+    def exportGitTags(self, gitTags):
+        validLabelRegexp = gitConfig("git-p4.labelExportRegexp")
+        if len(validLabelRegexp) == 0:
+            validLabelRegexp = defaultLabelRegexp
+        m = re.compile(validLabelRegexp)
+
+        for name in gitTags:
+
+            if not m.match(name):
+                if verbose:
+                    print "tag %s does not match regexp %s" % (name, validLabelRegexp)
+                continue
+
+            # Get the p4 commit this corresponds to
+            logMessage = extractLogMessageFromGitCommit(name)
+            values = extractSettingsGitLog(logMessage)
+
+            if not values.has_key('change'):
+                # a tag pointing to something not sent to p4; ignore
+                if verbose:
+                    print "git tag %s does not give a p4 commit" % name
+                continue
+            else:
+                changelist = values['change']
+
+            # Get the tag details.
+            inHeader = True
+            isAnnotated = False
+            body = []
+            for l in read_pipe_lines(["git", "cat-file", "-p", name]):
+                l = l.strip()
+                if inHeader:
+                    if re.match(r'tag\s+', l):
+                        isAnnotated = True
+                    elif re.match(r'\s*$', l):
+                        inHeader = False
+                        continue
+                else:
+                    body.append(l)
+
+            if not isAnnotated:
+                body = ["lightweight tag imported by git p4\n"]
+
+            # Create the label - use the same view as the client spec we are using
+            clientSpec = getClientSpec()
+
+            labelTemplate  = "Label: %s\n" % name
+            labelTemplate += "Description:\n"
+            for b in body:
+                labelTemplate += "\t" + b + "\n"
+            labelTemplate += "View:\n"
+            for depot_side in clientSpec.mappings:
+                labelTemplate += "\t%s\n" % depot_side
+
+            if self.dry_run:
+                print "Would create p4 label %s for tag" % name
+            elif self.prepare_p4_only:
+                print "Not creating p4 label %s for tag due to option" \
+                      " --prepare-p4-only" % name
+            else:
+                p4_write_pipe(["label", "-i"], labelTemplate)
+
+                # Use the label
+                p4_system(["tag", "-l", name] +
+                          ["%s@%s" % (depot_side, changelist) for depot_side in clientSpec.mappings])
+
+                if verbose:
+                    print "created p4 label for tag %s" % name
+
+    def run(self, args):
+        if len(args) == 0:
+            self.master = currentGitBranch()
+            if len(self.master) == 0 or not gitBranchExists("refs/heads/%s" % self.master):
+                die("Detecting current git branch failed!")
+        elif len(args) == 1:
+            self.master = args[0]
+            if not branchExists(self.master):
+                die("Branch %s does not exist" % self.master)
+        else:
+            return False
+
+        allowSubmit = gitConfig("git-p4.allowSubmit")
+        if len(allowSubmit) > 0 and not self.master in allowSubmit.split(","):
+            die("%s is not in git-p4.allowSubmit" % self.master)
+
+        [upstream, settings] = findUpstreamBranchPoint()
+        self.depotPath = settings['depot-paths'][0]
+        if len(self.origin) == 0:
+            self.origin = upstream
+
+        if self.preserveUser:
+            if not self.canChangeChangelists():
+                die("Cannot preserve user names without p4 super-user or admin permissions")
+
+        # if not set from the command line, try the config file
+        if self.conflict_behavior is None:
+            val = gitConfig("git-p4.conflict")
+            if val:
+                if val not in self.conflict_behavior_choices:
+                    die("Invalid value '%s' for config git-p4.conflict" % val)
+            else:
+                val = "ask"
+            self.conflict_behavior = val
+
+        if self.verbose:
+            print "Origin branch is " + self.origin
+
+        if len(self.depotPath) == 0:
+            print "Internal error: cannot locate perforce depot path from existing branches"
+            sys.exit(128)
+
+        self.useClientSpec = False
+        if gitConfigBool("git-p4.useclientspec"):
+            self.useClientSpec = True
+        if self.useClientSpec:
+            self.clientSpecDirs = getClientSpec()
+
+        if self.useClientSpec:
+            # all files are relative to the client spec
+            self.clientPath = getClientRoot()
+        else:
+            self.clientPath = p4Where(self.depotPath)
+
+        if self.clientPath == "":
+            die("Error: Cannot locate perforce checkout of %s in client view" % self.depotPath)
+
+        print "Perforce checkout for depot path %s located at %s" % (self.depotPath, self.clientPath)
+        self.oldWorkingDirectory = os.getcwd()
+
+        # ensure the clientPath exists
+        new_client_dir = False
+        if not os.path.exists(self.clientPath):
+            new_client_dir = True
+            os.makedirs(self.clientPath)
+
+        chdir(self.clientPath, is_client_path=True)
+        if self.dry_run:
+            print "Would synchronize p4 checkout in %s" % self.clientPath
+        else:
+            print "Synchronizing p4 checkout..."
+            if new_client_dir:
+                # old one was destroyed, and maybe nobody told p4
+                p4_sync("...", "-f")
+            else:
+                p4_sync("...")
+        self.check()
+
+        commits = []
+        for line in read_pipe_lines(["git", "rev-list", "--no-merges", "%s..%s" % (self.origin, self.master)]):
+            commits.append(line.strip())
+        commits.reverse()
+
+        if self.preserveUser or gitConfigBool("git-p4.skipUserNameCheck"):
+            self.checkAuthorship = False
+        else:
+            self.checkAuthorship = True
+
+        if self.preserveUser:
+            self.checkValidP4Users(commits)
+
+        #
+        # Build up a set of options to be passed to diff when
+        # submitting each commit to p4.
+        #
+        if self.detectRenames:
+            # command-line -M arg
+            self.diffOpts = "-M"
+        else:
+            # If not explicitly set check the config variable
+            detectRenames = gitConfig("git-p4.detectRenames")
+
+            if detectRenames.lower() == "false" or detectRenames == "":
+                self.diffOpts = ""
+            elif detectRenames.lower() == "true":
+                self.diffOpts = "-M"
+            else:
+                self.diffOpts = "-M%s" % detectRenames
+
+        # no command-line arg for -C or --find-copies-harder, just
+        # config variables
+        detectCopies = gitConfig("git-p4.detectCopies")
+        if detectCopies.lower() == "false" or detectCopies == "":
+            pass
+        elif detectCopies.lower() == "true":
+            self.diffOpts += " -C"
+        else:
+            self.diffOpts += " -C%s" % detectCopies
+
+        if gitConfigBool("git-p4.detectCopiesHarder"):
+            self.diffOpts += " --find-copies-harder"
+
+        #
+        # Apply the commits, one at a time.  On failure, ask if should
+        # continue to try the rest of the patches, or quit.
+        #
+        if self.dry_run:
+            print "Would apply"
+        applied = []
+        last = len(commits) - 1
+        for i, commit in enumerate(commits):
+            if self.dry_run:
+                print " ", read_pipe(["git", "show", "-s",
+                                      "--format=format:%h %s", commit])
+                ok = True
+            else:
+                ok = self.applyCommit(commit)
+            if ok:
+                applied.append(commit)
+            else:
+                if self.prepare_p4_only and i < last:
+                    print "Processing only the first commit due to option" \
+                          " --prepare-p4-only"
+                    break
+                if i < last:
+                    quit = False
+                    while True:
+                        # prompt for what to do, or use the option/variable
+                        if self.conflict_behavior == "ask":
+                            print "What do you want to do?"
+                            response = raw_input("[s]kip this commit but apply"
+                                                 " the rest, or [q]uit? ")
+                            if not response:
+                                continue
+                        elif self.conflict_behavior == "skip":
+                            response = "s"
+                        elif self.conflict_behavior == "quit":
+                            response = "q"
+                        else:
+                            die("Unknown conflict_behavior '%s'" %
+                                self.conflict_behavior)
+
+                        if response[0] == "s":
+                            print "Skipping this commit, but applying the rest"
+                            break
+                        if response[0] == "q":
+                            print "Quitting"
+                            quit = True
+                            break
+                    if quit:
+                        break
+
+        chdir(self.oldWorkingDirectory)
+
+        if self.dry_run:
+            pass
+        elif self.prepare_p4_only:
+            pass
+        elif len(commits) == len(applied):
+            print "All commits applied!"
+
+            sync = P4Sync()
+            if self.branch:
+                sync.branch = self.branch
+            sync.run([])
+
+            rebase = P4Rebase()
+            rebase.rebase()
+
+        else:
+            if len(applied) == 0:
+                print "No commits applied."
+            else:
+                print "Applied only the commits marked with '*':"
+                for c in commits:
+                    if c in applied:
+                        star = "*"
+                    else:
+                        star = " "
+                    print star, read_pipe(["git", "show", "-s",
+                                           "--format=format:%h %s",  c])
+                print "You will have to do 'git p4 sync' and rebase."
+
+        if gitConfigBool("git-p4.exportLabels"):
+            self.exportLabels = True
+
+        if self.exportLabels:
+            p4Labels = getP4Labels(self.depotPath)
+            gitTags = getGitTags()
+
+            missingGitTags = gitTags - p4Labels
+            self.exportGitTags(missingGitTags)
+
+        # exit with error unless everything applied perfectly
+        if len(commits) != len(applied):
+                sys.exit(1)
+
+        return True
+
+class View(object):
+    """Represent a p4 view ("p4 help views"), and map files in a
+       repo according to the view."""
+
+    def __init__(self, client_name):
+        self.mappings = []
+        self.client_prefix = "//%s/" % client_name
+        # cache results of "p4 where" to lookup client file locations
+        self.client_spec_path_cache = {}
+
+    def append(self, view_line):
+        """Parse a view line, splitting it into depot and client
+           sides.  Append to self.mappings, preserving order.  This
+           is only needed for tag creation."""
+
+        # Split the view line into exactly two words.  P4 enforces
+        # structure on these lines that simplifies this quite a bit.
+        #
+        # Either or both words may be double-quoted.
+        # Single quotes do not matter.
+        # Double-quote marks cannot occur inside the words.
+        # A + or - prefix is also inside the quotes.
+        # There are no quotes unless they contain a space.
+        # The line is already white-space stripped.
+        # The two words are separated by a single space.
+        #
+        if view_line[0] == '"':
+            # First word is double quoted.  Find its end.
+            close_quote_index = view_line.find('"', 1)
+            if close_quote_index <= 0:
+                die("No first-word closing quote found: %s" % view_line)
+            depot_side = view_line[1:close_quote_index]
+            # skip closing quote and space
+            rhs_index = close_quote_index + 1 + 1
+        else:
+            space_index = view_line.find(" ")
+            if space_index <= 0:
+                die("No word-splitting space found: %s" % view_line)
+            depot_side = view_line[0:space_index]
+            rhs_index = space_index + 1
+
+        # prefix + means overlay on previous mapping
+        if depot_side.startswith("+"):
+            depot_side = depot_side[1:]
+
+        # prefix - means exclude this path, leave out of mappings
+        exclude = False
+        if depot_side.startswith("-"):
+            exclude = True
+            depot_side = depot_side[1:]
+
+        if not exclude:
+            self.mappings.append(depot_side)
+
+    def convert_client_path(self, clientFile):
+        # chop off //client/ part to make it relative
+        if not clientFile.startswith(self.client_prefix):
+            die("No prefix '%s' on clientFile '%s'" %
+                (self.client_prefix, clientFile))
+        return clientFile[len(self.client_prefix):]
+
+    def update_client_spec_path_cache(self, files):
+        """ Caching file paths by "p4 where" batch query """
+
+        # List depot file paths exclude that already cached
+        fileArgs = [f['path'] for f in files if f['path'] not in self.client_spec_path_cache]
+
+        if len(fileArgs) == 0:
+            return  # All files in cache
+
+        where_result = p4CmdList(["-x", "-", "where"], stdin=fileArgs)
+        for res in where_result:
+            if "code" in res and res["code"] == "error":
+                # assume error is "... file(s) not in client view"
+                continue
+            if "clientFile" not in res:
+                die("No clientFile from 'p4 where %s'" % depot_path)
+            if "unmap" in res:
+                # it will list all of them, but only one not unmap-ped
+                continue
+            self.client_spec_path_cache[res['depotFile']] = self.convert_client_path(res["clientFile"])
+
+        # not found files or unmap files set to ""
+        for depotFile in fileArgs:
+            if depotFile not in self.client_spec_path_cache:
+                self.client_spec_path_cache[depotFile] = ""
+
+    def map_in_client(self, depot_path):
+        """Return the relative location in the client where this
+           depot file should live.  Returns "" if the file should
+           not be mapped in the client."""
+
+        if depot_path in self.client_spec_path_cache:
+            return self.client_spec_path_cache[depot_path]
+
+        die( "Error: %s is not found in client spec path" % depot_path )
+        return ""
+
+class P4Sync(Command, P4UserMap):
+    delete_actions = ( "delete", "move/delete", "purge" )
+
+    def __init__(self):
+        Command.__init__(self)
+        P4UserMap.__init__(self)
+        self.options = [
+                optparse.make_option("--branch", dest="branch"),
+                optparse.make_option("--detect-branches", dest="detectBranches", action="store_true"),
+                optparse.make_option("--changesfile", dest="changesFile"),
+                optparse.make_option("--silent", dest="silent", action="store_true"),
+                optparse.make_option("--detect-labels", dest="detectLabels", action="store_true"),
+                optparse.make_option("--import-labels", dest="importLabels", action="store_true"),
+                optparse.make_option("--import-local", dest="importIntoRemotes", action="store_false",
+                                     help="Import into refs/heads/ , not refs/remotes"),
+                optparse.make_option("--max-changes", dest="maxChanges"),
+                optparse.make_option("--keep-path", dest="keepRepoPath", action='store_true',
+                                     help="Keep entire BRANCH/DIR/SUBDIR prefix during import"),
+                optparse.make_option("--use-client-spec", dest="useClientSpec", action='store_true',
+                                     help="Only sync files that are included in the Perforce Client Spec")
+        ]
+        self.description = """Imports from Perforce into a git repository.\n
+    example:
+    //depot/my/project/ -- to import the current head
+    //depot/my/project/@all -- to import everything
+    //depot/my/project/@1,6 -- to import only from revision 1 to 6
+
+    (a ... is not needed in the path p4 specification, it's added implicitly)"""
+
+        self.usage += " //depot/path[@revRange]"
+        self.silent = False
+        self.createdBranches = set()
+        self.committedChanges = set()
+        self.branch = ""
+        self.detectBranches = False
+        self.detectLabels = False
+        self.importLabels = False
+        self.changesFile = ""
+        self.syncWithOrigin = True
+        self.importIntoRemotes = True
+        self.maxChanges = ""
+        self.keepRepoPath = False
+        self.depotPaths = None
+        self.p4BranchesInGit = []
+        self.cloneExclude = []
+        self.useClientSpec = False
+        self.useClientSpec_from_options = False
+        self.clientSpecDirs = None
+        self.tempBranches = []
+        self.tempBranchLocation = "git-p4-tmp"
+
+        if gitConfig("git-p4.syncFromOrigin") == "false":
+            self.syncWithOrigin = False
+
+    # Force a checkpoint in fast-import and wait for it to finish
+    def checkpoint(self):
+        self.gitStream.write("checkpoint\n\n")
+        self.gitStream.write("progress checkpoint\n\n")
+        out = self.gitOutput.readline()
+        if self.verbose:
+            print "checkpoint finished: " + out
+
+    def extractFilesFromCommit(self, commit):
+        self.cloneExclude = [re.sub(r"\.\.\.$", "", path)
+                             for path in self.cloneExclude]
+        files = []
+        fnum = 0
+        while commit.has_key("depotFile%s" % fnum):
+            path =  commit["depotFile%s" % fnum]
+
+            if [p for p in self.cloneExclude
+                if p4PathStartsWith(path, p)]:
+                found = False
+            else:
+                found = [p for p in self.depotPaths
+                         if p4PathStartsWith(path, p)]
+            if not found:
+                fnum = fnum + 1
+                continue
+
+            file = {}
+            file["path"] = path
+            file["rev"] = commit["rev%s" % fnum]
+            file["action"] = commit["action%s" % fnum]
+            file["type"] = commit["type%s" % fnum]
+            files.append(file)
+            fnum = fnum + 1
+        return files
+
+    def stripRepoPath(self, path, prefixes):
+        """When streaming files, this is called to map a p4 depot path
+           to where it should go in git.  The prefixes are either
+           self.depotPaths, or self.branchPrefixes in the case of
+           branch detection."""
+
+        if self.useClientSpec:
+            # branch detection moves files up a level (the branch name)
+            # from what client spec interpretation gives
+            path = self.clientSpecDirs.map_in_client(path)
+            if self.detectBranches:
+                for b in self.knownBranches:
+                    if path.startswith(b + "/"):
+                        path = path[len(b)+1:]
+
+        elif self.keepRepoPath:
+            # Preserve everything in relative path name except leading
+            # //depot/; just look at first prefix as they all should
+            # be in the same depot.
+            depot = re.sub("^(//[^/]+/).*", r'\1', prefixes[0])
+            if p4PathStartsWith(path, depot):
+                path = path[len(depot):]
+
+        else:
+            for p in prefixes:
+                if p4PathStartsWith(path, p):
+                    path = path[len(p):]
+                    break
+
+        path = wildcard_decode(path)
+        return path
+
+    def splitFilesIntoBranches(self, commit):
+        """Look at each depotFile in the commit to figure out to what
+           branch it belongs."""
+
+        if self.clientSpecDirs:
+            files = self.extractFilesFromCommit(commit)
+            self.clientSpecDirs.update_client_spec_path_cache(files)
+
+        branches = {}
+        fnum = 0
+        while commit.has_key("depotFile%s" % fnum):
+            path =  commit["depotFile%s" % fnum]
+            found = [p for p in self.depotPaths
+                     if p4PathStartsWith(path, p)]
+            if not found:
+                fnum = fnum + 1
+                continue
+
+            file = {}
+            file["path"] = path
+            file["rev"] = commit["rev%s" % fnum]
+            file["action"] = commit["action%s" % fnum]
+            file["type"] = commit["type%s" % fnum]
+            fnum = fnum + 1
+
+            # start with the full relative path where this file would
+            # go in a p4 client
+            if self.useClientSpec:
+                relPath = self.clientSpecDirs.map_in_client(path)
+            else:
+                relPath = self.stripRepoPath(path, self.depotPaths)
+
+            for branch in self.knownBranches.keys():
+                # add a trailing slash so that a commit into qt/4.2foo
+                # doesn't end up in qt/4.2, e.g.
+                if relPath.startswith(branch + "/"):
+                    if branch not in branches:
+                        branches[branch] = []
+                    branches[branch].append(file)
+                    break
+
+        return branches
+
+    # output one file from the P4 stream
+    # - helper for streamP4Files
+
+    def streamOneP4File(self, file, contents):
+        relPath = self.stripRepoPath(file['depotFile'], self.branchPrefixes)
+        if verbose:
+            sys.stderr.write("%s\n" % relPath)
+
+        (type_base, type_mods) = split_p4_type(file["type"])
+
+        git_mode = "100644"
+        if "x" in type_mods:
+            git_mode = "100755"
+        if type_base == "symlink":
+            git_mode = "120000"
+            # p4 print on a symlink sometimes contains "target\n";
+            # if it does, remove the newline
+            data = ''.join(contents)
+            if data[-1] == '\n':
+                contents = [data[:-1]]
+            else:
+                contents = [data]
+
+        if type_base == "utf16":
+            # p4 delivers different text in the python output to -G
+            # than it does when using "print -o", or normal p4 client
+            # operations.  utf16 is converted to ascii or utf8, perhaps.
+            # But ascii text saved as -t utf16 is completely mangled.
+            # Invoke print -o to get the real contents.
+            #
+            # On windows, the newlines will always be mangled by print, so put
+            # them back too.  This is not needed to the cygwin windows version,
+            # just the native "NT" type.
+            #
+            text = p4_read_pipe(['print', '-q', '-o', '-', file['depotFile']])
+            if p4_version_string().find("/NT") >= 0:
+                text = text.replace("\r\n", "\n")
+            contents = [ text ]
+
+        if type_base == "apple":
+            # Apple filetype files will be streamed as a concatenation of
+            # its appledouble header and the contents.  This is useless
+            # on both macs and non-macs.  If using "print -q -o xx", it
+            # will create "xx" with the data, and "%xx" with the header.
+            # This is also not very useful.
+            #
+            # Ideally, someday, this script can learn how to generate
+            # appledouble files directly and import those to git, but
+            # non-mac machines can never find a use for apple filetype.
+            print "\nIgnoring apple filetype file %s" % file['depotFile']
+            return
+
+        # Note that we do not try to de-mangle keywords on utf16 files,
+        # even though in theory somebody may want that.
+        pattern = p4_keywords_regexp_for_type(type_base, type_mods)
+        if pattern:
+            regexp = re.compile(pattern, re.VERBOSE)
+            text = ''.join(contents)
+            text = regexp.sub(r'$\1$', text)
+            contents = [ text ]
+
+        self.gitStream.write("M %s inline %s\n" % (git_mode, relPath))
+
+        # total length...
+        length = 0
+        for d in contents:
+            length = length + len(d)
+
+        self.gitStream.write("data %d\n" % length)
+        for d in contents:
+            self.gitStream.write(d)
+        self.gitStream.write("\n")
+
+    def streamOneP4Deletion(self, file):
+        relPath = self.stripRepoPath(file['path'], self.branchPrefixes)
+        if verbose:
+            sys.stderr.write("delete %s\n" % relPath)
+        self.gitStream.write("D %s\n" % relPath)
+
+    # handle another chunk of streaming data
+    def streamP4FilesCb(self, marshalled):
+
+        # catch p4 errors and complain
+        err = None
+        if "code" in marshalled:
+            if marshalled["code"] == "error":
+                if "data" in marshalled:
+                    err = marshalled["data"].rstrip()
+        if err:
+            f = None
+            if self.stream_have_file_info:
+                if "depotFile" in self.stream_file:
+                    f = self.stream_file["depotFile"]
+            # force a failure in fast-import, else an empty
+            # commit will be made
+            self.gitStream.write("\n")
+            self.gitStream.write("die-now\n")
+            self.gitStream.close()
+            # ignore errors, but make sure it exits first
+            self.importProcess.wait()
+            if f:
+                die("Error from p4 print for %s: %s" % (f, err))
+            else:
+                die("Error from p4 print: %s" % err)
+
+        if marshalled.has_key('depotFile') and self.stream_have_file_info:
+            # start of a new file - output the old one first
+            self.streamOneP4File(self.stream_file, self.stream_contents)
+            self.stream_file = {}
+            self.stream_contents = []
+            self.stream_have_file_info = False
+
+        # pick up the new file information... for the
+        # 'data' field we need to append to our array
+        for k in marshalled.keys():
+            if k == 'data':
+                self.stream_contents.append(marshalled['data'])
+            else:
+                self.stream_file[k] = marshalled[k]
+
+        self.stream_have_file_info = True
+
+    # Stream directly from "p4 files" into "git fast-import"
+    def streamP4Files(self, files):
+        filesForCommit = []
+        filesToRead = []
+        filesToDelete = []
+
+        for f in files:
+            # if using a client spec, only add the files that have
+            # a path in the client
+            if self.clientSpecDirs:
+                if self.clientSpecDirs.map_in_client(f['path']) == "":
+                    continue
+
+            filesForCommit.append(f)
+            if f['action'] in self.delete_actions:
+                filesToDelete.append(f)
+            else:
+                filesToRead.append(f)
+
+        # deleted files...
+        for f in filesToDelete:
+            self.streamOneP4Deletion(f)
+
+        if len(filesToRead) > 0:
+            self.stream_file = {}
+            self.stream_contents = []
+            self.stream_have_file_info = False
+
+            # curry self argument
+            def streamP4FilesCbSelf(entry):
+                self.streamP4FilesCb(entry)
+
+            fileArgs = ['%s#%s' % (f['path'], f['rev']) for f in filesToRead]
+
+            p4CmdList(["-x", "-", "print"],
+                      stdin=fileArgs,
+                      cb=streamP4FilesCbSelf)
+
+            # do the last chunk
+            if self.stream_file.has_key('depotFile'):
+                self.streamOneP4File(self.stream_file, self.stream_contents)
+
+    def make_email(self, userid):
+        if userid in self.users:
+            return self.users[userid]
+        else:
+            return "%s <a@b>" % userid
+
+    # Stream a p4 tag
+    def streamTag(self, gitStream, labelName, labelDetails, commit, epoch):
+        if verbose:
+            print "writing tag %s for commit %s" % (labelName, commit)
+        gitStream.write("tag %s\n" % labelName)
+        gitStream.write("from %s\n" % commit)
+
+        if labelDetails.has_key('Owner'):
+            owner = labelDetails["Owner"]
+        else:
+            owner = None
+
+        # Try to use the owner of the p4 label, or failing that,
+        # the current p4 user id.
+        if owner:
+            email = self.make_email(owner)
+        else:
+            email = self.make_email(self.p4UserId())
+        tagger = "%s %s %s" % (email, epoch, self.tz)
+
+        gitStream.write("tagger %s\n" % tagger)
+
+        print "labelDetails=",labelDetails
+        if labelDetails.has_key('Description'):
+            description = labelDetails['Description']
+        else:
+            description = 'Label from git p4'
+
+        gitStream.write("data %d\n" % len(description))
+        gitStream.write(description)
+        gitStream.write("\n")
+
+    def commit(self, details, files, branch, parent = ""):
+        epoch = details["time"]
+        author = details["user"]
+
+        if self.verbose:
+            print "commit into %s" % branch
+
+        # start with reading files; if that fails, we should not
+        # create a commit.
+        new_files = []
+        for f in files:
+            if [p for p in self.branchPrefixes if p4PathStartsWith(f['path'], p)]:
+                new_files.append (f)
+            else:
+                sys.stderr.write("Ignoring file outside of prefix: %s\n" % f['path'])
+
+        if self.clientSpecDirs:
+            self.clientSpecDirs.update_client_spec_path_cache(files)
+
+        self.gitStream.write("commit %s\n" % branch)
+#        gitStream.write("mark :%s\n" % details["change"])
+        self.committedChanges.add(int(details["change"]))
+        committer = ""
+        if author not in self.users:
+            self.getUserMapFromPerforceServer()
+        committer = "%s %s %s" % (self.make_email(author), epoch, self.tz)
+
+        self.gitStream.write("committer %s\n" % committer)
+
+        self.gitStream.write("data <<EOT\n")
+        self.gitStream.write(details["desc"])
+        self.gitStream.write("\n[git-p4: depot-paths = \"%s\": change = %s" %
+                             (','.join(self.branchPrefixes), details["change"]))
+        if len(details['options']) > 0:
+            self.gitStream.write(": options = %s" % details['options'])
+        self.gitStream.write("]\nEOT\n\n")
+
+        if len(parent) > 0:
+            if self.verbose:
+                print "parent %s" % parent
+            self.gitStream.write("from %s\n" % parent)
+
+        self.streamP4Files(new_files)
+        self.gitStream.write("\n")
+
+        change = int(details["change"])
+
+        if self.labels.has_key(change):
+            label = self.labels[change]
+            labelDetails = label[0]
+            labelRevisions = label[1]
+            if self.verbose:
+                print "Change %s is labelled %s" % (change, labelDetails)
+
+            files = p4CmdList(["files"] + ["%s...@%s" % (p, change)
+                                                for p in self.branchPrefixes])
+
+            if len(files) == len(labelRevisions):
+
+                cleanedFiles = {}
+                for info in files:
+                    if info["action"] in self.delete_actions:
+                        continue
+                    cleanedFiles[info["depotFile"]] = info["rev"]
+
+                if cleanedFiles == labelRevisions:
+                    self.streamTag(self.gitStream, 'tag_%s' % labelDetails['label'], labelDetails, branch, epoch)
+
+                else:
+                    if not self.silent:
+                        print ("Tag %s does not match with change %s: files do not match."
+                               % (labelDetails["label"], change))
+
+            else:
+                if not self.silent:
+                    print ("Tag %s does not match with change %s: file count is different."
+                           % (labelDetails["label"], change))
+
+    # Build a dictionary of changelists and labels, for "detect-labels" option.
+    def getLabels(self):
+        self.labels = {}
+
+        l = p4CmdList(["labels"] + ["%s..." % p for p in self.depotPaths])
+        if len(l) > 0 and not self.silent:
+            print "Finding files belonging to labels in %s" % `self.depotPaths`
+
+        for output in l:
+            label = output["label"]
+            revisions = {}
+            newestChange = 0
+            if self.verbose:
+                print "Querying files for label %s" % label
+            for file in p4CmdList(["files"] +
+                                      ["%s...@%s" % (p, label)
+                                          for p in self.depotPaths]):
+                revisions[file["depotFile"]] = file["rev"]
+                change = int(file["change"])
+                if change > newestChange:
+                    newestChange = change
+
+            self.labels[newestChange] = [output, revisions]
+
+        if self.verbose:
+            print "Label changes: %s" % self.labels.keys()
+
+    # Import p4 labels as git tags. A direct mapping does not
+    # exist, so assume that if all the files are at the same revision
+    # then we can use that, or it's something more complicated we should
+    # just ignore.
+    def importP4Labels(self, stream, p4Labels):
+        if verbose:
+            print "import p4 labels: " + ' '.join(p4Labels)
+
+        ignoredP4Labels = gitConfigList("git-p4.ignoredP4Labels")
+        validLabelRegexp = gitConfig("git-p4.labelImportRegexp")
+        if len(validLabelRegexp) == 0:
+            validLabelRegexp = defaultLabelRegexp
+        m = re.compile(validLabelRegexp)
+
+        for name in p4Labels:
+            commitFound = False
+
+            if not m.match(name):
+                if verbose:
+                    print "label %s does not match regexp %s" % (name,validLabelRegexp)
+                continue
+
+            if name in ignoredP4Labels:
+                continue
+
+            labelDetails = p4CmdList(['label', "-o", name])[0]
+
+            # get the most recent changelist for each file in this label
+            change = p4Cmd(["changes", "-m", "1"] + ["%s...@%s" % (p, name)
+                                for p in self.depotPaths])
+
+            if change.has_key('change'):
+                # find the corresponding git commit; take the oldest commit
+                changelist = int(change['change'])
+                gitCommit = read_pipe(["git", "rev-list", "--max-count=1",
+                     "--reverse", ":/\[git-p4:.*change = %d\]" % changelist])
+                if len(gitCommit) == 0:
+                    print "could not find git commit for changelist %d" % changelist
+                else:
+                    gitCommit = gitCommit.strip()
+                    commitFound = True
+                    # Convert from p4 time format
+                    try:
+                        tmwhen = time.strptime(labelDetails['Update'], "%Y/%m/%d %H:%M:%S")
+                    except ValueError:
+                        print "Could not convert label time %s" % labelDetails['Update']
+                        tmwhen = 1
+
+                    when = int(time.mktime(tmwhen))
+                    self.streamTag(stream, name, labelDetails, gitCommit, when)
+                    if verbose:
+                        print "p4 label %s mapped to git commit %s" % (name, gitCommit)
+            else:
+                if verbose:
+                    print "Label %s has no changelists - possibly deleted?" % name
+
+            if not commitFound:
+                # We can't import this label; don't try again as it will get very
+                # expensive repeatedly fetching all the files for labels that will
+                # never be imported. If the label is moved in the future, the
+                # ignore will need to be removed manually.
+                system(["git", "config", "--add", "git-p4.ignoredP4Labels", name])
+
+    def guessProjectName(self):
+        for p in self.depotPaths:
+            if p.endswith("/"):
+                p = p[:-1]
+            p = p[p.strip().rfind("/") + 1:]
+            if not p.endswith("/"):
+               p += "/"
+            return p
+
+    def getBranchMapping(self):
+        lostAndFoundBranches = set()
+
+        user = gitConfig("git-p4.branchUser")
+        if len(user) > 0:
+            command = "branches -u %s" % user
+        else:
+            command = "branches"
+
+        for info in p4CmdList(command):
+            details = p4Cmd(["branch", "-o", info["branch"]])
+            viewIdx = 0
+            while details.has_key("View%s" % viewIdx):
+                paths = details["View%s" % viewIdx].split(" ")
+                viewIdx = viewIdx + 1
+                # require standard //depot/foo/... //depot/bar/... mapping
+                if len(paths) != 2 or not paths[0].endswith("/...") or not paths[1].endswith("/..."):
+                    continue
+                source = paths[0]
+                destination = paths[1]
+                ## HACK
+                if p4PathStartsWith(source, self.depotPaths[0]) and p4PathStartsWith(destination, self.depotPaths[0]):
+                    source = source[len(self.depotPaths[0]):-4]
+                    destination = destination[len(self.depotPaths[0]):-4]
+
+                    if destination in self.knownBranches:
+                        if not self.silent:
+                            print "p4 branch %s defines a mapping from %s to %s" % (info["branch"], source, destination)
+                            print "but there exists another mapping from %s to %s already!" % (self.knownBranches[destination], destination)
+                        continue
+
+                    self.knownBranches[destination] = source
+
+                    lostAndFoundBranches.discard(destination)
+
+                    if source not in self.knownBranches:
+                        lostAndFoundBranches.add(source)
+
+        # Perforce does not strictly require branches to be defined, so we also
+        # check git config for a branch list.
+        #
+        # Example of branch definition in git config file:
+        # [git-p4]
+        #   branchList=main:branchA
+        #   branchList=main:branchB
+        #   branchList=branchA:branchC
+        configBranches = gitConfigList("git-p4.branchList")
+        for branch in configBranches:
+            if branch:
+                (source, destination) = branch.split(":")
+                self.knownBranches[destination] = source
+
+                lostAndFoundBranches.discard(destination)
+
+                if source not in self.knownBranches:
+                    lostAndFoundBranches.add(source)
+
+
+        for branch in lostAndFoundBranches:
+            self.knownBranches[branch] = branch
+
+    def getBranchMappingFromGitBranches(self):
+        branches = p4BranchesInGit(self.importIntoRemotes)
+        for branch in branches.keys():
+            if branch == "master":
+                branch = "main"
+            else:
+                branch = branch[len(self.projectName):]
+            self.knownBranches[branch] = branch
+
+    def updateOptionDict(self, d):
+        option_keys = {}
+        if self.keepRepoPath:
+            option_keys['keepRepoPath'] = 1
+
+        d["options"] = ' '.join(sorted(option_keys.keys()))
+
+    def readOptions(self, d):
+        self.keepRepoPath = (d.has_key('options')
+                             and ('keepRepoPath' in d['options']))
+
+    def gitRefForBranch(self, branch):
+        if branch == "main":
+            return self.refPrefix + "master"
+
+        if len(branch) <= 0:
+            return branch
+
+        return self.refPrefix + self.projectName + branch
+
+    def gitCommitByP4Change(self, ref, change):
+        if self.verbose:
+            print "looking in ref " + ref + " for change %s using bisect..." % change
+
+        earliestCommit = ""
+        latestCommit = parseRevision(ref)
+
+        while True:
+            if self.verbose:
+                print "trying: earliest %s latest %s" % (earliestCommit, latestCommit)
+            next = read_pipe("git rev-list --bisect %s %s" % (latestCommit, earliestCommit)).strip()
+            if len(next) == 0:
+                if self.verbose:
+                    print "argh"
+                return ""
+            log = extractLogMessageFromGitCommit(next)
+            settings = extractSettingsGitLog(log)
+            currentChange = int(settings['change'])
+            if self.verbose:
+                print "current change %s" % currentChange
+
+            if currentChange == change:
+                if self.verbose:
+                    print "found %s" % next
+                return next
+
+            if currentChange < change:
+                earliestCommit = "^%s" % next
+            else:
+                latestCommit = "%s" % next
+
+        return ""
+
+    def importNewBranch(self, branch, maxChange):
+        # make fast-import flush all changes to disk and update the refs using the checkpoint
+        # command so that we can try to find the branch parent in the git history
+        self.gitStream.write("checkpoint\n\n");
+        self.gitStream.flush();
+        branchPrefix = self.depotPaths[0] + branch + "/"
+        range = "@1,%s" % maxChange
+        #print "prefix" + branchPrefix
+        changes = p4ChangesForPaths([branchPrefix], range)
+        if len(changes) <= 0:
+            return False
+        firstChange = changes[0]
+        #print "first change in branch: %s" % firstChange
+        sourceBranch = self.knownBranches[branch]
+        sourceDepotPath = self.depotPaths[0] + sourceBranch
+        sourceRef = self.gitRefForBranch(sourceBranch)
+        #print "source " + sourceBranch
+
+        branchParentChange = int(p4Cmd(["changes", "-m", "1", "%s...@1,%s" % (sourceDepotPath, firstChange)])["change"])
+        #print "branch parent: %s" % branchParentChange
+        gitParent = self.gitCommitByP4Change(sourceRef, branchParentChange)
+        if len(gitParent) > 0:
+            self.initialParents[self.gitRefForBranch(branch)] = gitParent
+            #print "parent git commit: %s" % gitParent
+
+        self.importChanges(changes)
+        return True
+
+    def searchParent(self, parent, branch, target):
+        parentFound = False
+        for blob in read_pipe_lines(["git", "rev-list", "--reverse",
+                                     "--no-merges", parent]):
+            blob = blob.strip()
+            if len(read_pipe(["git", "diff-tree", blob, target])) == 0:
+                parentFound = True
+                if self.verbose:
+                    print "Found parent of %s in commit %s" % (branch, blob)
+                break
+        if parentFound:
+            return blob
+        else:
+            return None
+
+    def importChanges(self, changes):
+        cnt = 1
+        for change in changes:
+            description = p4_describe(change)
+            self.updateOptionDict(description)
+
+            if not self.silent:
+                sys.stdout.write("\rImporting revision %s (%s%%)" % (change, cnt * 100 / len(changes)))
+                sys.stdout.flush()
+            cnt = cnt + 1
+
+            try:
+                if self.detectBranches:
+                    branches = self.splitFilesIntoBranches(description)
+                    for branch in branches.keys():
+                        ## HACK  --hwn
+                        branchPrefix = self.depotPaths[0] + branch + "/"
+                        self.branchPrefixes = [ branchPrefix ]
+
+                        parent = ""
+
+                        filesForCommit = branches[branch]
+
+                        if self.verbose:
+                            print "branch is %s" % branch
+
+                        self.updatedBranches.add(branch)
+
+                        if branch not in self.createdBranches:
+                            self.createdBranches.add(branch)
+                            parent = self.knownBranches[branch]
+                            if parent == branch:
+                                parent = ""
+                            else:
+                                fullBranch = self.projectName + branch
+                                if fullBranch not in self.p4BranchesInGit:
+                                    if not self.silent:
+                                        print("\n    Importing new branch %s" % fullBranch);
+                                    if self.importNewBranch(branch, change - 1):
+                                        parent = ""
+                                        self.p4BranchesInGit.append(fullBranch)
+                                    if not self.silent:
+                                        print("\n    Resuming with change %s" % change);
+
+                                if self.verbose:
+                                    print "parent determined through known branches: %s" % parent
+
+                        branch = self.gitRefForBranch(branch)
+                        parent = self.gitRefForBranch(parent)
+
+                        if self.verbose:
+                            print "looking for initial parent for %s; current parent is %s" % (branch, parent)
+
+                        if len(parent) == 0 and branch in self.initialParents:
+                            parent = self.initialParents[branch]
+                            del self.initialParents[branch]
+
+                        blob = None
+                        if len(parent) > 0:
+                            tempBranch = "%s/%d" % (self.tempBranchLocation, change)
+                            if self.verbose:
+                                print "Creating temporary branch: " + tempBranch
+                            self.commit(description, filesForCommit, tempBranch)
+                            self.tempBranches.append(tempBranch)
+                            self.checkpoint()
+                            blob = self.searchParent(parent, branch, tempBranch)
+                        if blob:
+                            self.commit(description, filesForCommit, branch, blob)
+                        else:
+                            if self.verbose:
+                                print "Parent of %s not found. Committing into head of %s" % (branch, parent)
+                            self.commit(description, filesForCommit, branch, parent)
+                else:
+                    files = self.extractFilesFromCommit(description)
+                    self.commit(description, files, self.branch,
+                                self.initialParent)
+                    # only needed once, to connect to the previous commit
+                    self.initialParent = ""
+            except IOError:
+                print self.gitError.read()
+                sys.exit(1)
+
+    def importHeadRevision(self, revision):
+        print "Doing initial import of %s from revision %s into %s" % (' '.join(self.depotPaths), revision, self.branch)
+
+        details = {}
+        details["user"] = "git perforce import user"
+        details["desc"] = ("Initial import of %s from the state at revision %s\n"
+                           % (' '.join(self.depotPaths), revision))
+        details["change"] = revision
+        newestRevision = 0
+
+        fileCnt = 0
+        fileArgs = ["%s...%s" % (p,revision) for p in self.depotPaths]
+
+        for info in p4CmdList(["files"] + fileArgs):
+
+            if 'code' in info and info['code'] == 'error':
+                sys.stderr.write("p4 returned an error: %s\n"
+                                 % info['data'])
+                if info['data'].find("must refer to client") >= 0:
+                    sys.stderr.write("This particular p4 error is misleading.\n")
+                    sys.stderr.write("Perhaps the depot path was misspelled.\n");
+                    sys.stderr.write("Depot path:  %s\n" % " ".join(self.depotPaths))
+                sys.exit(1)
+            if 'p4ExitCode' in info:
+                sys.stderr.write("p4 exitcode: %s\n" % info['p4ExitCode'])
+                sys.exit(1)
+
+
+            change = int(info["change"])
+            if change > newestRevision:
+                newestRevision = change
+
+            if info["action"] in self.delete_actions:
+                # don't increase the file cnt, otherwise details["depotFile123"] will have gaps!
+                #fileCnt = fileCnt + 1
+                continue
+
+            for prop in ["depotFile", "rev", "action", "type" ]:
+                details["%s%s" % (prop, fileCnt)] = info[prop]
+
+            fileCnt = fileCnt + 1
+
+        details["change"] = newestRevision
+
+        # Use time from top-most change so that all git p4 clones of
+        # the same p4 repo have the same commit SHA1s.
+        res = p4_describe(newestRevision)
+        details["time"] = res["time"]
+
+        self.updateOptionDict(details)
+        try:
+            self.commit(details, self.extractFilesFromCommit(details), self.branch)
+        except IOError:
+            print "IO error with git fast-import. Is your git version recent enough?"
+            print self.gitError.read()
+
+
+    def run(self, args):
+        self.depotPaths = []
+        self.changeRange = ""
+        self.previousDepotPaths = []
+        self.hasOrigin = False
+
+        # map from branch depot path to parent branch
+        self.knownBranches = {}
+        self.initialParents = {}
+
+        if self.importIntoRemotes:
+            self.refPrefix = "refs/remotes/p4/"
+        else:
+            self.refPrefix = "refs/heads/p4/"
+
+        if self.syncWithOrigin:
+            self.hasOrigin = originP4BranchesExist()
+            if self.hasOrigin:
+                if not self.silent:
+                    print 'Syncing with origin first, using "git fetch origin"'
+                system("git fetch origin")
+
+        branch_arg_given = bool(self.branch)
+        if len(self.branch) == 0:
+            self.branch = self.refPrefix + "master"
+            if gitBranchExists("refs/heads/p4") and self.importIntoRemotes:
+                system("git update-ref %s refs/heads/p4" % self.branch)
+                system("git branch -D p4")
+
+        # accept either the command-line option, or the configuration variable
+        if self.useClientSpec:
+            # will use this after clone to set the variable
+            self.useClientSpec_from_options = True
+        else:
+            if gitConfigBool("git-p4.useclientspec"):
+                self.useClientSpec = True
+        if self.useClientSpec:
+            self.clientSpecDirs = getClientSpec()
+
+        # TODO: should always look at previous commits,
+        # merge with previous imports, if possible.
+        if args == []:
+            if self.hasOrigin:
+                createOrUpdateBranchesFromOrigin(self.refPrefix, self.silent)
+
+            # branches holds mapping from branch name to sha1
+            branches = p4BranchesInGit(self.importIntoRemotes)
+
+            # restrict to just this one, disabling detect-branches
+            if branch_arg_given:
+                short = self.branch.split("/")[-1]
+                if short in branches:
+                    self.p4BranchesInGit = [ short ]
+            else:
+                self.p4BranchesInGit = branches.keys()
+
+            if len(self.p4BranchesInGit) > 1:
+                if not self.silent:
+                    print "Importing from/into multiple branches"
+                self.detectBranches = True
+                for branch in branches.keys():
+                    self.initialParents[self.refPrefix + branch] = \
+                        branches[branch]
+
+            if self.verbose:
+                print "branches: %s" % self.p4BranchesInGit
+
+            p4Change = 0
+            for branch in self.p4BranchesInGit:
+                logMsg =  extractLogMessageFromGitCommit(self.refPrefix + branch)
+
+                settings = extractSettingsGitLog(logMsg)
+
+                self.readOptions(settings)
+                if (settings.has_key('depot-paths')
+                    and settings.has_key ('change')):
+                    change = int(settings['change']) + 1
+                    p4Change = max(p4Change, change)
+
+                    depotPaths = sorted(settings['depot-paths'])
+                    if self.previousDepotPaths == []:
+                        self.previousDepotPaths = depotPaths
+                    else:
+                        paths = []
+                        for (prev, cur) in zip(self.previousDepotPaths, depotPaths):
+                            prev_list = prev.split("/")
+                            cur_list = cur.split("/")
+                            for i in range(0, min(len(cur_list), len(prev_list))):
+                                if cur_list[i] <> prev_list[i]:
+                                    i = i - 1
+                                    break
+
+                            paths.append ("/".join(cur_list[:i + 1]))
+
+                        self.previousDepotPaths = paths
+
+            if p4Change > 0:
+                self.depotPaths = sorted(self.previousDepotPaths)
+                self.changeRange = "@%s,#head" % p4Change
+                if not self.silent and not self.detectBranches:
+                    print "Performing incremental import into %s git branch" % self.branch
+
+        # accept multiple ref name abbreviations:
+        #    refs/foo/bar/branch -> use it exactly
+        #    p4/branch -> prepend refs/remotes/ or refs/heads/
+        #    branch -> prepend refs/remotes/p4/ or refs/heads/p4/
+        if not self.branch.startswith("refs/"):
+            if self.importIntoRemotes:
+                prepend = "refs/remotes/"
+            else:
+                prepend = "refs/heads/"
+            if not self.branch.startswith("p4/"):
+                prepend += "p4/"
+            self.branch = prepend + self.branch
+
+        if len(args) == 0 and self.depotPaths:
+            if not self.silent:
+                print "Depot paths: %s" % ' '.join(self.depotPaths)
+        else:
+            if self.depotPaths and self.depotPaths != args:
+                print ("previous import used depot path %s and now %s was specified. "
+                       "This doesn't work!" % (' '.join (self.depotPaths),
+                                               ' '.join (args)))
+                sys.exit(1)
+
+            self.depotPaths = sorted(args)
+
+        revision = ""
+        self.users = {}
+
+        # Make sure no revision specifiers are used when --changesfile
+        # is specified.
+        bad_changesfile = False
+        if len(self.changesFile) > 0:
+            for p in self.depotPaths:
+                if p.find("@") >= 0 or p.find("#") >= 0:
+                    bad_changesfile = True
+                    break
+        if bad_changesfile:
+            die("Option --changesfile is incompatible with revision specifiers")
+
+        newPaths = []
+        for p in self.depotPaths:
+            if p.find("@") != -1:
+                atIdx = p.index("@")
+                self.changeRange = p[atIdx:]
+                if self.changeRange == "@all":
+                    self.changeRange = ""
+                elif ',' not in self.changeRange:
+                    revision = self.changeRange
+                    self.changeRange = ""
+                p = p[:atIdx]
+            elif p.find("#") != -1:
+                hashIdx = p.index("#")
+                revision = p[hashIdx:]
+                p = p[:hashIdx]
+            elif self.previousDepotPaths == []:
+                # pay attention to changesfile, if given, else import
+                # the entire p4 tree at the head revision
+                if len(self.changesFile) == 0:
+                    revision = "#head"
+
+            p = re.sub ("\.\.\.$", "", p)
+            if not p.endswith("/"):
+                p += "/"
+
+            newPaths.append(p)
+
+        self.depotPaths = newPaths
+
+        # --detect-branches may change this for each branch
+        self.branchPrefixes = self.depotPaths
+
+        self.loadUserMapFromCache()
+        self.labels = {}
+        if self.detectLabels:
+            self.getLabels();
+
+        if self.detectBranches:
+            ## FIXME - what's a P4 projectName ?
+            self.projectName = self.guessProjectName()
+
+            if self.hasOrigin:
+                self.getBranchMappingFromGitBranches()
+            else:
+                self.getBranchMapping()
+            if self.verbose:
+                print "p4-git branches: %s" % self.p4BranchesInGit
+                print "initial parents: %s" % self.initialParents
+            for b in self.p4BranchesInGit:
+                if b != "master":
+
+                    ## FIXME
+                    b = b[len(self.projectName):]
+                self.createdBranches.add(b)
+
+        self.tz = "%+03d%02d" % (- time.timezone / 3600, ((- time.timezone % 3600) / 60))
+
+        self.importProcess = subprocess.Popen(["git", "fast-import"],
+                                              stdin=subprocess.PIPE,
+                                              stdout=subprocess.PIPE,
+                                              stderr=subprocess.PIPE);
+        self.gitOutput = self.importProcess.stdout
+        self.gitStream = self.importProcess.stdin
+        self.gitError = self.importProcess.stderr
+
+        if revision:
+            self.importHeadRevision(revision)
+        else:
+            changes = []
+
+            if len(self.changesFile) > 0:
+                output = open(self.changesFile).readlines()
+                changeSet = set()
+                for line in output:
+                    changeSet.add(int(line))
+
+                for change in changeSet:
+                    changes.append(change)
+
+                changes.sort()
+            else:
+                # catch "git p4 sync" with no new branches, in a repo that
+                # does not have any existing p4 branches
+                if len(args) == 0:
+                    if not self.p4BranchesInGit:
+                        die("No remote p4 branches.  Perhaps you never did \"git p4 clone\" in here.")
+
+                    # The default branch is master, unless --branch is used to
+                    # specify something else.  Make sure it exists, or complain
+                    # nicely about how to use --branch.
+                    if not self.detectBranches:
+                        if not branch_exists(self.branch):
+                            if branch_arg_given:
+                                die("Error: branch %s does not exist." % self.branch)
+                            else:
+                                die("Error: no branch %s; perhaps specify one with --branch." %
+                                    self.branch)
+
+                if self.verbose:
+                    print "Getting p4 changes for %s...%s" % (', '.join(self.depotPaths),
+                                                              self.changeRange)
+                changes = p4ChangesForPaths(self.depotPaths, self.changeRange)
+
+                if len(self.maxChanges) > 0:
+                    changes = changes[:min(int(self.maxChanges), len(changes))]
+
+            if len(changes) == 0:
+                if not self.silent:
+                    print "No changes to import!"
+            else:
+                if not self.silent and not self.detectBranches:
+                    print "Import destination: %s" % self.branch
+
+                self.updatedBranches = set()
+
+                if not self.detectBranches:
+                    if args:
+                        # start a new branch
+                        self.initialParent = ""
+                    else:
+                        # build on a previous revision
+                        self.initialParent = parseRevision(self.branch)
+
+                self.importChanges(changes)
+
+                if not self.silent:
+                    print ""
+                    if len(self.updatedBranches) > 0:
+                        sys.stdout.write("Updated branches: ")
+                        for b in self.updatedBranches:
+                            sys.stdout.write("%s " % b)
+                        sys.stdout.write("\n")
+
+        if gitConfigBool("git-p4.importLabels"):
+            self.importLabels = True
+
+        if self.importLabels:
+            p4Labels = getP4Labels(self.depotPaths)
+            gitTags = getGitTags()
+
+            missingP4Labels = p4Labels - gitTags
+            self.importP4Labels(self.gitStream, missingP4Labels)
+
+        self.gitStream.close()
+        if self.importProcess.wait() != 0:
+            die("fast-import failed: %s" % self.gitError.read())
+        self.gitOutput.close()
+        self.gitError.close()
+
+        # Cleanup temporary branches created during import
+        if self.tempBranches != []:
+            for branch in self.tempBranches:
+                read_pipe("git update-ref -d %s" % branch)
+            os.rmdir(os.path.join(os.environ.get("GIT_DIR", ".git"), self.tempBranchLocation))
+
+        # Create a symbolic ref p4/HEAD pointing to p4/<branch> to allow
+        # a convenient shortcut refname "p4".
+        if self.importIntoRemotes:
+            head_ref = self.refPrefix + "HEAD"
+            if not gitBranchExists(head_ref) and gitBranchExists(self.branch):
+                system(["git", "symbolic-ref", head_ref, self.branch])
+
+        return True
+
+class P4Rebase(Command):
+    def __init__(self):
+        Command.__init__(self)
+        self.options = [
+                optparse.make_option("--import-labels", dest="importLabels", action="store_true"),
+        ]
+        self.importLabels = False
+        self.description = ("Fetches the latest revision from perforce and "
+                            + "rebases the current work (branch) against it")
+
+    def run(self, args):
+        sync = P4Sync()
+        sync.importLabels = self.importLabels
+        sync.run([])
+
+        return self.rebase()
+
+    def rebase(self):
+        if os.system("git update-index --refresh") != 0:
+            die("Some files in your working directory are modified and different than what is in your index. You can use git update-index <filename> to bring the index up-to-date or stash away all your changes with git stash.");
+        if len(read_pipe("git diff-index HEAD --")) > 0:
+            die("You have uncommitted changes. Please commit them before rebasing or stash them away with git stash.");
+
+        [upstream, settings] = findUpstreamBranchPoint()
+        if len(upstream) == 0:
+            die("Cannot find upstream branchpoint for rebase")
+
+        # the branchpoint may be p4/foo~3, so strip off the parent
+        upstream = re.sub("~[0-9]+$", "", upstream)
+
+        print "Rebasing the current branch onto %s" % upstream
+        oldHead = read_pipe("git rev-parse HEAD").strip()
+        system("git rebase %s" % upstream)
+        system("git diff-tree --stat --summary -M %s HEAD" % oldHead)
+        return True
+
+class P4Clone(P4Sync):
+    def __init__(self):
+        P4Sync.__init__(self)
+        self.description = "Creates a new git repository and imports from Perforce into it"
+        self.usage = "usage: %prog [options] //depot/path[@revRange]"
+        self.options += [
+            optparse.make_option("--destination", dest="cloneDestination",
+                                 action='store', default=None,
+                                 help="where to leave result of the clone"),
+            optparse.make_option("-/", dest="cloneExclude",
+                                 action="append", type="string",
+                                 help="exclude depot path"),
+            optparse.make_option("--bare", dest="cloneBare",
+                                 action="store_true", default=False),
+        ]
+        self.cloneDestination = None
+        self.needsGit = False
+        self.cloneBare = False
+
+    # This is required for the "append" cloneExclude action
+    def ensure_value(self, attr, value):
+        if not hasattr(self, attr) or getattr(self, attr) is None:
+            setattr(self, attr, value)
+        return getattr(self, attr)
+
+    def defaultDestination(self, args):
+        ## TODO: use common prefix of args?
+        depotPath = args[0]
+        depotDir = re.sub("(@[^@]*)$", "", depotPath)
+        depotDir = re.sub("(#[^#]*)$", "", depotDir)
+        depotDir = re.sub(r"\.\.\.$", "", depotDir)
+        depotDir = re.sub(r"/$", "", depotDir)
+        return os.path.split(depotDir)[1]
+
+    def run(self, args):
+        if len(args) < 1:
+            return False
+
+        if self.keepRepoPath and not self.cloneDestination:
+            sys.stderr.write("Must specify destination for --keep-path\n")
+            sys.exit(1)
+
+        depotPaths = args
+
+        if not self.cloneDestination and len(depotPaths) > 1:
+            self.cloneDestination = depotPaths[-1]
+            depotPaths = depotPaths[:-1]
+
+        self.cloneExclude = ["/"+p for p in self.cloneExclude]
+        for p in depotPaths:
+            if not p.startswith("//"):
+                sys.stderr.write('Depot paths must start with "//": %s\n' % p)
+                return False
+
+        if not self.cloneDestination:
+            self.cloneDestination = self.defaultDestination(args)
+
+        print "Importing from %s into %s" % (', '.join(depotPaths), self.cloneDestination)
+
+        if not os.path.exists(self.cloneDestination):
+            os.makedirs(self.cloneDestination)
+        chdir(self.cloneDestination)
+
+        init_cmd = [ "git", "init" ]
+        if self.cloneBare:
+            init_cmd.append("--bare")
+        retcode = subprocess.call(init_cmd)
+        if retcode:
+            raise CalledProcessError(retcode, init_cmd)
+
+        if not P4Sync.run(self, depotPaths):
+            return False
+
+        # create a master branch and check out a work tree
+        if gitBranchExists(self.branch):
+            system([ "git", "branch", "master", self.branch ])
+            if not self.cloneBare:
+                system([ "git", "checkout", "-f" ])
+        else:
+            print 'Not checking out any branch, use ' \
+                  '"git checkout -q -b master <branch>"'
+
+        # auto-set this variable if invoked with --use-client-spec
+        if self.useClientSpec_from_options:
+            system("git config --bool git-p4.useclientspec true")
+
+        return True
+
+class P4Branches(Command):
+    def __init__(self):
+        Command.__init__(self)
+        self.options = [ ]
+        self.description = ("Shows the git branches that hold imports and their "
+                            + "corresponding perforce depot paths")
+        self.verbose = False
+
+    def run(self, args):
+        if originP4BranchesExist():
+            createOrUpdateBranchesFromOrigin()
+
+        cmdline = "git rev-parse --symbolic "
+        cmdline += " --remotes"
+
+        for line in read_pipe_lines(cmdline):
+            line = line.strip()
+
+            if not line.startswith('p4/') or line == "p4/HEAD":
+                continue
+            branch = line
+
+            log = extractLogMessageFromGitCommit("refs/remotes/%s" % branch)
+            settings = extractSettingsGitLog(log)
+
+            print "%s <= %s (%s)" % (branch, ",".join(settings["depot-paths"]), settings["change"])
+        return True
+
+class HelpFormatter(optparse.IndentedHelpFormatter):
+    def __init__(self):
+        optparse.IndentedHelpFormatter.__init__(self)
+
+    def format_description(self, description):
+        if description:
+            return description + "\n"
+        else:
+            return ""
+
+def printUsage(commands):
+    print "usage: %s <command> [options]" % sys.argv[0]
+    print ""
+    print "valid commands: %s" % ", ".join(commands)
+    print ""
+    print "Try %s <command> --help for command specific help." % sys.argv[0]
+    print ""
+
+commands = {
+    "debug" : P4Debug,
+    "submit" : P4Submit,
+    "commit" : P4Submit,
+    "sync" : P4Sync,
+    "rebase" : P4Rebase,
+    "clone" : P4Clone,
+    "rollback" : P4RollBack,
+    "branches" : P4Branches
+}
+
+
+def main():
+    if len(sys.argv[1:]) == 0:
+        printUsage(commands.keys())
+        sys.exit(2)
+
+    cmdName = sys.argv[1]
+    try:
+        klass = commands[cmdName]
+        cmd = klass()
+    except KeyError:
+        print "unknown command %s" % cmdName
+        print ""
+        printUsage(commands.keys())
+        sys.exit(2)
+
+    options = cmd.options
+    cmd.gitdir = os.environ.get("GIT_DIR", None)
+
+    args = sys.argv[2:]
+
+    options.append(optparse.make_option("--verbose", "-v", dest="verbose", action="store_true"))
+    if cmd.needsGit:
+        options.append(optparse.make_option("--git-dir", dest="gitdir"))
+
+    parser = optparse.OptionParser(cmd.usage.replace("%prog", "%prog " + cmdName),
+                                   options,
+                                   description = cmd.description,
+                                   formatter = HelpFormatter())
+
+    (cmd, args) = parser.parse_args(sys.argv[2:], cmd);
+    global verbose
+    verbose = cmd.verbose
+    if cmd.needsGit:
+        if cmd.gitdir == None:
+            cmd.gitdir = os.path.abspath(".git")
+            if not isValidGitDir(cmd.gitdir):
+                cmd.gitdir = read_pipe("git rev-parse --git-dir").strip()
+                if os.path.exists(cmd.gitdir):
+                    cdup = read_pipe("git rev-parse --show-cdup").strip()
+                    if len(cdup) > 0:
+                        chdir(cdup);
+
+        if not isValidGitDir(cmd.gitdir):
+            if isValidGitDir(cmd.gitdir + "/.git"):
+                cmd.gitdir += "/.git"
+            else:
+                die("fatal: cannot locate git repository at %s" % cmd.gitdir)
+
+        os.environ["GIT_DIR"] = cmd.gitdir
+
+    if not cmd.run(args):
+        parser.print_help()
+        sys.exit(2)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/integrations/perforce/license.txt b/integrations/perforce/license.txt
new file mode 100644
index 00000000..411b58f9
--- /dev/null
+++ b/integrations/perforce/license.txt
@@ -0,0 +1,26 @@
+git_p4.py was downloaded from https://raw.github.com/git/git/34022ba/git-p4.py
+
+The header of that file references <http://opensource.org/licenses/mit-license.php>,
+the textual contents of which are included below.
+
+The MIT License (MIT)
+
+Copyright (c) <year> <copyright holders>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.