Imported Upstream version 2.30.0
[platform/upstream/git.git] / git-p4.py
index 882b1bb..6ae5bbf 100755 (executable)
--- a/git-p4.py
+++ b/git-p4.py
@@ -7,16 +7,55 @@
 #            2007 Trolltech ASA
 # License: MIT <http://www.opensource.org/licenses/mit-license.php>
 #
-
-import optparse, sys, os, marshal, subprocess, shelve
-import tempfile, getopt, os.path, time, platform
-import re, shutil
+# pylint: disable=invalid-name,missing-docstring,too-many-arguments,broad-except
+# pylint: disable=no-self-use,wrong-import-position,consider-iterating-dictionary
+# pylint: disable=wrong-import-order,unused-import,too-few-public-methods
+# pylint: disable=too-many-lines,ungrouped-imports,fixme,too-many-locals
+# pylint: disable=line-too-long,bad-whitespace,superfluous-parens
+# pylint: disable=too-many-statements,too-many-instance-attributes
+# pylint: disable=too-many-branches,too-many-nested-blocks
+#
+import sys
+if sys.version_info.major < 3 and sys.version_info.minor < 7:
+    sys.stderr.write("git-p4: requires Python 2.7 or later.\n")
+    sys.exit(1)
+import os
+import optparse
+import functools
+import marshal
+import subprocess
+import tempfile
+import time
+import platform
+import re
+import shutil
+import stat
+import zipfile
+import zlib
+import ctypes
+import errno
+import glob
+
+# On python2.7 where raw_input() and input() are both availble,
+# we want raw_input's semantics, but aliased to input for python3
+# compatibility
+# support basestring in python3
+try:
+    if raw_input and input:
+        input = raw_input
+except:
+    pass
 
 verbose = False
 
 # Only labels/tags matching this will be imported/exported
 defaultLabelRegexp = r'[a-zA-Z0-9_\-.]+$'
 
+# The block size is reduced automatically if required
+defaultBlockSize = 1<<20
+
+p4_access_checked = False
+
 def p4_build_cmd(cmd):
     """Build a suitable p4 command line.
 
@@ -46,32 +85,199 @@ def p4_build_cmd(cmd):
     if len(client) > 0:
         real_cmd += ["-c", client]
 
+    retries = gitConfigInt("git-p4.retries")
+    if retries is None:
+        # Perform 3 retries by default
+        retries = 3
+    if retries > 0:
+        # Provide a way to not pass this option by setting git-p4.retries to 0
+        real_cmd += ["-r", str(retries)]
 
-    if isinstance(cmd,basestring):
+    if not isinstance(cmd, list):
         real_cmd = ' '.join(real_cmd) + ' ' + cmd
     else:
         real_cmd += cmd
+
+    # now check that we can actually talk to the server
+    global p4_access_checked
+    if not p4_access_checked:
+        p4_access_checked = True    # suppress access checks in p4_check_access itself
+        p4_check_access()
+
     return real_cmd
 
-def chdir(dir):
-    # P4 uses the PWD environment variable rather than getcwd(). Since we're
-    # not using the shell, we have to set it ourselves.  This path could
-    # be relative, so go there first, then figure out where we ended up.
-    os.chdir(dir)
-    os.environ['PWD'] = os.getcwd()
+def git_dir(path):
+    """ Return TRUE if the given path is a git directory (/path/to/dir/.git).
+        This won't automatically add ".git" to a directory.
+    """
+    d = read_pipe(["git", "--git-dir", path, "rev-parse", "--git-dir"], True).strip()
+    if not d or len(d) == 0:
+        return None
+    else:
+        return d
+
+def chdir(path, is_client_path=False):
+    """Do chdir to the given path, and set the PWD environment
+       variable for use by P4.  It does not look at getcwd() output.
+       Since we're not using the shell, it is necessary to set the
+       PWD environment variable explicitly.
+
+       Normally, expand the path to force it to be absolute.  This
+       addresses the use of relative path names inside P4 settings,
+       e.g. P4CONFIG=.p4config.  P4 does not simply open the filename
+       as given; it looks for .p4config using PWD.
+
+       If is_client_path, the path was handed to us directly by p4,
+       and may be a symbolic link.  Do not call os.getcwd() in this
+       case, because it will cause p4 to think that PWD is not inside
+       the client path.
+       """
+
+    os.chdir(path)
+    if not is_client_path:
+        path = os.getcwd()
+    os.environ['PWD'] = path
+
+def calcDiskFree():
+    """Return free space in bytes on the disk of the given dirname."""
+    if platform.system() == 'Windows':
+        free_bytes = ctypes.c_ulonglong(0)
+        ctypes.windll.kernel32.GetDiskFreeSpaceExW(ctypes.c_wchar_p(os.getcwd()), None, None, ctypes.pointer(free_bytes))
+        return free_bytes.value
+    else:
+        st = os.statvfs(os.getcwd())
+        return st.f_bavail * st.f_frsize
 
 def die(msg):
+    """ Terminate execution. Make sure that any running child processes have been wait()ed for before
+        calling this.
+    """
     if verbose:
         raise Exception(msg)
     else:
         sys.stderr.write(msg + "\n")
         sys.exit(1)
 
+def prompt(prompt_text):
+    """ Prompt the user to choose one of the choices
+
+    Choices are identified in the prompt_text by square brackets around
+    a single letter option.
+    """
+    choices = set(m.group(1) for m in re.finditer(r"\[(.)\]", prompt_text))
+    while True:
+        sys.stderr.flush()
+        sys.stdout.write(prompt_text)
+        sys.stdout.flush()
+        response=sys.stdin.readline().strip().lower()
+        if not response:
+            continue
+        response = response[0]
+        if response in choices:
+            return response
+
+# We need different encoding/decoding strategies for text data being passed
+# around in pipes depending on python version
+if bytes is not str:
+    # For python3, always encode and decode as appropriate
+    def decode_text_stream(s):
+        return s.decode() if isinstance(s, bytes) else s
+    def encode_text_stream(s):
+        return s.encode() if isinstance(s, str) else s
+else:
+    # For python2.7, pass read strings as-is, but also allow writing unicode
+    def decode_text_stream(s):
+        return s
+    def encode_text_stream(s):
+        return s.encode('utf_8') if isinstance(s, unicode) else s
+
+def decode_path(path):
+    """Decode a given string (bytes or otherwise) using configured path encoding options
+    """
+    encoding = gitConfig('git-p4.pathEncoding') or 'utf_8'
+    if bytes is not str:
+        return path.decode(encoding, errors='replace') if isinstance(path, bytes) else path
+    else:
+        try:
+            path.decode('ascii')
+        except:
+            path = path.decode(encoding, errors='replace')
+            if verbose:
+                print('Path with non-ASCII characters detected. Used {} to decode: {}'.format(encoding, path))
+        return path
+
+def run_git_hook(cmd, param=[]):
+    """Execute a hook if the hook exists."""
+    if verbose:
+        sys.stderr.write("Looking for hook: %s\n" % cmd)
+        sys.stderr.flush()
+
+    hooks_path = gitConfig("core.hooksPath")
+    if len(hooks_path) <= 0:
+        hooks_path = os.path.join(os.environ["GIT_DIR"], "hooks")
+
+    if not isinstance(param, list):
+        param=[param]
+
+    # resolve hook file name, OS depdenent
+    hook_file = os.path.join(hooks_path, cmd)
+    if platform.system() == 'Windows':
+        if not os.path.isfile(hook_file):
+            # look for the file with an extension
+            files = glob.glob(hook_file + ".*")
+            if not files:
+                return True
+            files.sort()
+            hook_file = files.pop()
+            while hook_file.upper().endswith(".SAMPLE"):
+                # The file is a sample hook. We don't want it
+                if len(files) > 0:
+                    hook_file = files.pop()
+                else:
+                    return True
+
+    if not os.path.isfile(hook_file) or not os.access(hook_file, os.X_OK):
+        return True
+
+    return run_hook_command(hook_file, param) == 0
+
+def run_hook_command(cmd, param):
+    """Executes a git hook command
+       cmd = the command line file to be executed. This can be
+       a file that is run by OS association.
+
+       param = a list of parameters to pass to the cmd command
+
+       On windows, the extension is checked to see if it should
+       be run with the Git for Windows Bash shell.  If there
+       is no file extension, the file is deemed a bash shell
+       and will be handed off to sh.exe. Otherwise, Windows
+       will be called with the shell to handle the file assocation.
+
+       For non Windows operating systems, the file is called
+       as an executable.
+    """
+    cli = [cmd] + param
+    use_shell = False
+    if platform.system() == 'Windows':
+        (root,ext) = os.path.splitext(cmd)
+        if ext == "":
+            exe_path = os.environ.get("EXEPATH")
+            if exe_path is None:
+                exe_path = ""
+            else:
+                exe_path = os.path.join(exe_path, "bin")
+            cli = [os.path.join(exe_path, "SH.EXE")] + cli
+        else:
+            use_shell = True
+    return subprocess.call(cli, shell=use_shell)
+
+
 def write_pipe(c, stdin):
     if verbose:
         sys.stderr.write('Writing pipe: %s\n' % str(c))
 
-    expand = isinstance(c,basestring)
+    expand = not isinstance(c, list)
     p = subprocess.Popen(c, stdin=subprocess.PIPE, shell=expand)
     pipe = p.stdin
     val = pipe.write(stdin)
@@ -83,36 +289,64 @@ def write_pipe(c, stdin):
 
 def p4_write_pipe(c, stdin):
     real_cmd = p4_build_cmd(c)
+    if bytes is not str and isinstance(stdin, str):
+        stdin = encode_text_stream(stdin)
     return write_pipe(real_cmd, stdin)
 
-def read_pipe(c, ignore_error=False):
+def read_pipe_full(c):
+    """ Read output from  command. Returns a tuple
+        of the return status, stdout text and stderr
+        text.
+    """
     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))
+    expand = not isinstance(c, list)
+    p = subprocess.Popen(c, stdout=subprocess.PIPE, stderr=subprocess.PIPE, shell=expand)
+    (out, err) = p.communicate()
+    return (p.returncode, out, decode_text_stream(err))
 
-    return val
+def read_pipe(c, ignore_error=False, raw=False):
+    """ Read output from  command. Returns the output text on
+        success. On failure, terminates execution, unless
+        ignore_error is True, when it returns an empty string.
 
-def p4_read_pipe(c, ignore_error=False):
+        If raw is True, do not attempt to decode output text.
+    """
+    (retcode, out, err) = read_pipe_full(c)
+    if retcode != 0:
+        if ignore_error:
+            out = ""
+        else:
+            die('Command failed: %s\nError: %s' % (str(c), err))
+    if not raw:
+        out = decode_text_stream(out)
+    return out
+
+def read_pipe_text(c):
+    """ Read output from a command with trailing whitespace stripped.
+        On error, returns None.
+    """
+    (retcode, out, err) = read_pipe_full(c)
+    if retcode != 0:
+        return None
+    else:
+        return decode_text_stream(out).rstrip()
+
+def p4_read_pipe(c, ignore_error=False, raw=False):
     real_cmd = p4_build_cmd(c)
-    return read_pipe(real_cmd, ignore_error)
+    return read_pipe(real_cmd, ignore_error, raw=raw)
 
 def read_pipe_lines(c):
     if verbose:
         sys.stderr.write('Reading pipe: %s\n' % str(c))
 
-    expand = isinstance(c, basestring)
+    expand = not isinstance(c, list)
     p = subprocess.Popen(c, stdout=subprocess.PIPE, shell=expand)
     pipe = p.stdout
-    val = pipe.readlines()
+    val = [decode_text_stream(line) for line in pipe.readlines()]
     if pipe.close() or p.wait():
         die('Command failed: %s' % str(c))
-
     return val
 
 def p4_read_pipe_lines(c):
@@ -129,17 +363,107 @@ def p4_has_command(cmd):
     p.communicate()
     return p.returncode == 0
 
-def system(cmd):
-    expand = isinstance(cmd,basestring)
+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()
+    err = decode_text_stream(err)
+    # return code will be 1 in either case
+    if err.find("Invalid option") >= 0:
+        return False
+    if err.find("disabled") >= 0:
+        return False
+    # assume it failed because @... was invalid changelist
+    return True
+
+def system(cmd, ignore_error=False):
+    expand = not isinstance(cmd, list)
     if verbose:
         sys.stderr.write("executing %s\n" % str(cmd))
-    subprocess.check_call(cmd, shell=expand)
+    retcode = subprocess.call(cmd, shell=expand)
+    if retcode and not ignore_error:
+        raise CalledProcessError(retcode, cmd)
+
+    return retcode
 
 def p4_system(cmd):
     """Specifically invoke p4 as the system command. """
     real_cmd = p4_build_cmd(cmd)
-    expand = isinstance(real_cmd, basestring)
-    subprocess.check_call(real_cmd, shell=expand)
+    expand = not isinstance(real_cmd, list)
+    retcode = subprocess.call(real_cmd, shell=expand)
+    if retcode:
+        raise CalledProcessError(retcode, real_cmd)
+
+def die_bad_access(s):
+    die("failure accessing depot: {0}".format(s.rstrip()))
+
+def p4_check_access(min_expiration=1):
+    """ Check if we can access Perforce - account still logged in
+    """
+    results = p4CmdList(["login", "-s"])
+
+    if len(results) == 0:
+        # should never get here: always get either some results, or a p4ExitCode
+        assert("could not parse response from perforce")
+
+    result = results[0]
+
+    if 'p4ExitCode' in result:
+        # p4 returned non-zero status, e.g. P4PORT invalid, or p4 not in path
+        die_bad_access("could not run p4")
+
+    code = result.get("code")
+    if not code:
+        # we get here if we couldn't connect and there was nothing to unmarshal
+        die_bad_access("could not connect")
+
+    elif code == "stat":
+        expiry = result.get("TicketExpiration")
+        if expiry:
+            expiry = int(expiry)
+            if expiry > min_expiration:
+                # ok to carry on
+                return
+            else:
+                die_bad_access("perforce ticket expires in {0} seconds".format(expiry))
+
+        else:
+            # account without a timeout - all ok
+            return
+
+    elif code == "error":
+        data = result.get("data")
+        if data:
+            die_bad_access("p4 error: {0}".format(data))
+        else:
+            die_bad_access("unknown error")
+    elif code == "info":
+        return
+    else:
+        die_bad_access("unknown error code {0}".format(code))
+
+_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)])
@@ -157,8 +481,8 @@ def p4_add(f):
 def p4_delete(f):
     p4_system(["delete", wildcard_encode(f)])
 
-def p4_edit(f):
-    p4_system(["edit"wildcard_encode(f)])
+def p4_edit(f, *options):
+    p4_system(["edit"] + list(options) + [wildcard_encode(f)])
 
 def p4_revert(f):
     p4_system(["revert", wildcard_encode(f)])
@@ -166,9 +490,45 @@ def p4_revert(f):
 def p4_reopen(type, f):
     p4_system(["reopen", "-t", type, wildcard_encode(f)])
 
+def p4_reopen_in_change(changelist, files):
+    cmd = ["reopen", "-c", str(changelist)] + files
+    p4_system(cmd)
+
 def p4_move(src, dest):
     p4_system(["move", "-k", wildcard_encode(src), wildcard_encode(dest)])
 
+def p4_last_change():
+    results = p4CmdList(["changes", "-m", "1"], skip_info=True)
+    return int(results[0]['change'])
+
+def p4_describe(change, shelved=False):
+    """Make sure it returns a valid result by checking for
+       the presence of field "time".  Return a dict of the
+       results."""
+
+    cmd = ["describe", "-s"]
+    if shelved:
+        cmd += ["-S"]
+    cmd += [str(change)]
+
+    ds = p4CmdList(cmd, skip_info=True)
+    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"
@@ -207,8 +567,8 @@ def split_p4_type(p4type):
 #
 # return the raw p4 type of a file (text, text+ko, etc)
 #
-def p4_type(file):
-    results = p4CmdList(["fstat", "-T", "headType", file])
+def p4_type(f):
+    results = p4CmdList(["fstat", "-T", "headType", wildcard_encode(f)])
     return results[0]['headType']
 
 #
@@ -227,7 +587,7 @@ def p4_keywords_regexp_for_type(base, type_mods):
         pattern = r"""
             \$              # Starts with a dollar, followed by...
             (%s)            # one of the keywords, followed by...
-            (:[^$]+)?       # possibly an old expansion, followed by...
+            (:[^$\n]+)?     # possibly an old expansion, followed by...
             \$              # another dollar
             """ % kwords
         return pattern
@@ -265,7 +625,7 @@ 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)
+    match = re.match(".*\((.+)\)( \*exclusive\*)?\r?$", result)
     if match:
         return match.group(1)
     else:
@@ -274,7 +634,7 @@ def getP4OpenedType(file):
 # Return the set of all p4 labels
 def getP4Labels(depotPaths):
     labels = set()
-    if isinstance(depotPaths,basestring):
+    if not isinstance(depotPaths, list):
         depotPaths = [depotPaths]
 
     for l in p4CmdList(["labels"] + ["%s..." % p for p in depotPaths]):
@@ -291,12 +651,7 @@ def getGitTags():
         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
+_diff_tree_pattern = None
 
 def parseDiffTreeEntry(entry):
     """Parses a single diff tree entry into its component elements.
@@ -317,7 +672,11 @@ def parseDiffTreeEntry(entry):
 
     If the pattern is not matched, None is returned."""
 
-    match = diffTreePattern().next().match(entry)
+    global _diff_tree_pattern
+    if not _diff_tree_pattern:
+        _diff_tree_pattern = re.compile(':(\d+) (\d+) (\w+) (\w+) ([A-Z])(\d+)?\t(.*?)((\t(.*))|$)')
+
+    match = _diff_tree_pattern.match(entry)
     if match:
         return {
             'src_mode': match.group(1),
@@ -336,12 +695,40 @@ def isModeExec(mode):
     # otherwise False.
     return mode[-3:] == "755"
 
+class P4Exception(Exception):
+    """ Base class for exceptions from the p4 client """
+    def __init__(self, exit_code):
+        self.p4ExitCode = exit_code
+
+class P4ServerException(P4Exception):
+    """ Base class for exceptions where we get some kind of marshalled up result from the server """
+    def __init__(self, exit_code, p4_result):
+        super(P4ServerException, self).__init__(exit_code)
+        self.p4_result = p4_result
+        self.code = p4_result[0]['code']
+        self.data = p4_result[0]['data']
+
+class P4RequestSizeException(P4ServerException):
+    """ One of the maxresults or maxscanrows errors """
+    def __init__(self, exit_code, p4_result, limit):
+        super(P4RequestSizeException, self).__init__(exit_code, p4_result)
+        self.limit = limit
+
+class P4CommandException(P4Exception):
+    """ Something went wrong calling p4 which means we have to give up """
+    def __init__(self, msg):
+        self.msg = msg
+
+    def __str__(self):
+        return self.msg
+
 def isModeExecChanged(src_mode, dst_mode):
     return isModeExec(src_mode) != isModeExec(dst_mode)
 
-def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None):
+def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None, skip_info=False,
+        errors_as_exceptions=False):
 
-    if isinstance(cmd,basestring):
+    if not isinstance(cmd, list):
         cmd = "-G " + cmd
         expand = True
     else:
@@ -358,11 +745,12 @@ def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None):
     stdin_file = None
     if stdin is not None:
         stdin_file = tempfile.TemporaryFile(prefix='p4-stdin', mode=stdin_mode)
-        if isinstance(stdin,basestring):
+        if not isinstance(stdin, list):
             stdin_file.write(stdin)
         else:
             for i in stdin:
-                stdin_file.write(i + '\n')
+                stdin_file.write(encode_text_stream(i))
+                stdin_file.write(b'\n')
         stdin_file.flush()
         stdin_file.seek(0)
 
@@ -375,6 +763,23 @@ def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None):
     try:
         while True:
             entry = marshal.load(p4.stdout)
+            if bytes is not str:
+                # Decode unmarshalled dict to use str keys and values, except for:
+                #   - `data` which may contain arbitrary binary data
+                #   - `depotFile[0-9]*`, `path`, or `clientFile` which may contain non-UTF8 encoded text
+                decoded_entry = {}
+                for key, value in entry.items():
+                    key = key.decode()
+                    if isinstance(value, bytes) and not (key in ('data', 'path', 'clientFile') or key.startswith('depotFile')):
+                        value = value.decode()
+                    decoded_entry[key] = value
+                # Parse out data if it's an error response
+                if decoded_entry.get('code') == 'error' and 'data' in decoded_entry:
+                    decoded_entry['data'] = decoded_entry['data'].decode()
+                entry = decoded_entry
+            if skip_info:
+                if 'code' in entry and entry['code'] == 'info':
+                    continue
             if cb is not None:
                 cb(entry)
             else:
@@ -383,9 +788,25 @@ def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None):
         pass
     exitCode = p4.wait()
     if exitCode != 0:
-        entry = {}
-        entry["p4ExitCode"] = exitCode
-        result.append(entry)
+        if errors_as_exceptions:
+            if len(result) > 0:
+                data = result[0].get('data')
+                if data:
+                    m = re.search('Too many rows scanned \(over (\d+)\)', data)
+                    if not m:
+                        m = re.search('Request too large \(over (\d+)\)', data)
+
+                    if m:
+                        limit = int(m.group(1))
+                        raise P4RequestSizeException(exitCode, result, limit)
+
+                raise P4ServerException(exitCode, result)
+            else:
+                raise P4Exception(exitCode)
+        else:
+            entry = {}
+            entry["p4ExitCode"] = exitCode
+            result.append(entry)
 
     return result
 
@@ -399,12 +820,15 @@ def p4Cmd(cmd):
 def p4Where(depotPath):
     if not depotPath.endswith("/"):
         depotPath += "/"
-    depotPath = depotPath + "..."
-    outputList = p4CmdList(["where", depotPath])
+    depotPathLong = depotPath + "..."
+    outputList = p4CmdList(["where", depotPathLong])
     output = None
     for entry in outputList:
         if "depotFile" in entry:
-            if entry["depotFile"] == depotPath:
+            # Search for the base client side depot path, as long as it starts with the branch's P4 path.
+            # The base path always ends with "/...".
+            entry_path = decode_path(entry['depotFile'])
+            if entry_path.find(depotPath) == 0 and entry_path[-4:] == "/...":
                 output = entry
                 break
         elif "data" in entry:
@@ -419,24 +843,21 @@ def p4Where(depotPath):
         return ""
     clientPath = ""
     if "path" in output:
-        clientPath = output.get("path")
+        clientPath = decode_path(output['path'])
     elif "data" in output:
         data = output.get("data")
-        lastSpace = data.rfind(" ")
-        clientPath = data[lastSpace + 1:]
+        lastSpace = data.rfind(b" ")
+        clientPath = decode_path(data[lastSpace + 1:])
 
     if clientPath.endswith("..."):
         clientPath = clientPath[:-3]
     return clientPath
 
 def currentGitBranch():
-    return read_pipe("git name-rev HEAD").split(" ")[1].strip()
+    return read_pipe_text(["git", "symbolic-ref", "--short", "-q", "HEAD"])
 
 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
+    return git_dir(path) != None
 
 def parseRevision(ref):
     return read_pipe("git rev-parse %s" % ref).strip()
@@ -451,7 +872,7 @@ def extractLogMessageFromGitCommit(commit):
 
     ## fixme: title is first line of commit, not 1st paragraph.
     foundTitle = False
-    for log in read_pipe_lines("git cat-file commit %s" % commit):
+    for log in read_pipe_lines(["git", "cat-file", "commit", commit]):
        if not foundTitle:
            if len(log) == 1:
                foundTitle = True
@@ -490,44 +911,96 @@ def gitBranchExists(branch):
                             stderr=subprocess.PIPE, stdout=subprocess.PIPE);
     return proc.wait() == 0;
 
+def gitUpdateRef(ref, newvalue):
+    subprocess.check_call(["git", "update-ref", ref, newvalue])
+
+def gitDeleteRef(ref):
+    subprocess.check_call(["git", "update-ref", "-d", ref])
+
 _gitConfig = {}
-def gitConfig(key, args = None): # set args to "--bool", for instance
-    if not _gitConfig.has_key(key):
-        argsFilter = ""
-        if args != None:
-            argsFilter = "%s " % args
-        cmd = "git config %s%s" % (argsFilter, key)
-        _gitConfig[key] = read_pipe(cmd, ignore_error=True).strip()
+
+def gitConfig(key, typeSpecifier=None):
+    if key not in _gitConfig:
+        cmd = [ "git", "config" ]
+        if typeSpecifier:
+            cmd += [ typeSpecifier ]
+        cmd += [ key ]
+        s = read_pipe(cmd, ignore_error=True)
+        _gitConfig[key] = s.strip()
+    return _gitConfig[key]
+
+def gitConfigBool(key):
+    """Return a bool, using git config --bool.  It is True only if the
+       variable is set to true, and False if set to false or not present
+       in the config."""
+
+    if key not in _gitConfig:
+        _gitConfig[key] = gitConfig(key, '--bool') == "true"
+    return _gitConfig[key]
+
+def gitConfigInt(key):
+    if key not in _gitConfig:
+        cmd = [ "git", "config", "--int", key ]
+        s = read_pipe(cmd, ignore_error=True)
+        v = s.strip()
+        try:
+            _gitConfig[key] = int(gitConfig(key, '--int'))
+        except ValueError:
+            _gitConfig[key] = None
     return _gitConfig[key]
 
 def gitConfigList(key):
-    if not _gitConfig.has_key(key):
-        _gitConfig[key] = read_pipe("git config --get-all %s" % key, ignore_error=True).strip().split(os.linesep)
+    if key not in _gitConfig:
+        s = read_pipe(["git", "config", "--get-all", key], ignore_error=True)
+        _gitConfig[key] = s.strip().splitlines()
+        if _gitConfig[key] == ['']:
+            _gitConfig[key] = []
     return _gitConfig[key]
 
-def p4BranchesInGit(branchesAreInRemotes = True):
+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"
+        cmdline += "--remotes"
     else:
-        cmdline += " --branches"
+        cmdline += "--branches"
 
     for line in read_pipe_lines(cmdline):
         line = line.strip()
 
-        ## only import to p4/
-        if not line.startswith('p4/') or line == "p4/HEAD":
+        # only import to p4/
+        if not line.startswith('p4/'):
+            continue
+        # special symbolic ref to p4/master
+        if line == "p4/HEAD":
             continue
-        branch = line
 
-        # strip off p4
-        branch = re.sub ("^p4/", "", line)
+        # 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()
+    out = decode_text_stream(out)
+    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
@@ -536,7 +1009,7 @@ def findUpstreamBranchPoint(head = "HEAD"):
         tip = branches[branch]
         log = extractLogMessageFromGitCommit(tip)
         settings = extractSettingsGitLog(log)
-        if settings.has_key("depot-paths"):
+        if "depot-paths" in settings:
             paths = ",".join(settings["depot-paths"])
             branchByDepotPath[paths] = "remotes/p4/" + branch
 
@@ -546,9 +1019,9 @@ def findUpstreamBranchPoint(head = "HEAD"):
         commit = head + "~%s" % parent
         log = extractLogMessageFromGitCommit(commit)
         settings = extractSettingsGitLog(log)
-        if settings.has_key("depot-paths"):
+        if "depot-paths" in settings:
             paths = ",".join(settings["depot-paths"])
-            if branchByDepotPath.has_key(paths):
+            if paths in branchByDepotPath:
                 return [branchByDepotPath[paths], settings]
 
         parent = parent + 1
@@ -557,7 +1030,7 @@ def findUpstreamBranchPoint(head = "HEAD"):
 
 def createOrUpdateBranchesFromOrigin(localRefPrefix = "refs/remotes/p4/", silent=True):
     if not silent:
-        print ("Creating/updating branch(es) in %s based on origin branch(es)"
+        print("Creating/updating branch(es) in %s based on origin branch(es)"
                % localRefPrefix)
 
     originPrefix = "origin/p4/"
@@ -572,29 +1045,29 @@ def createOrUpdateBranchesFromOrigin(localRefPrefix = "refs/remotes/p4/", silent
         originHead = line
 
         original = extractSettingsGitLog(extractLogMessageFromGitCommit(originHead))
-        if (not original.has_key('depot-paths')
-            or not original.has_key('change')):
+        if ('depot-paths' not in original
+            or 'change' not in original):
             continue
 
         update = False
         if not gitBranchExists(remoteHead):
             if verbose:
-                print "creating %s" % remoteHead
+                print("creating %s" % remoteHead)
             update = True
         else:
             settings = extractSettingsGitLog(extractLogMessageFromGitCommit(remoteHead))
-            if settings.has_key('change') > 0:
+            if 'change' in settings:
                 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). "
+                        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 "
+                    print("Ignoring: %s was imported from %s while "
                            "%s was imported from %s"
                            % (originHead, ','.join(original['depot-paths']),
                               remoteHead, ','.join(settings['depot-paths'])))
@@ -605,21 +1078,98 @@ def createOrUpdateBranchesFromOrigin(localRefPrefix = "refs/remotes/p4/", silent
 def originP4BranchesExist():
         return gitBranchExists("origin") or gitBranchExists("origin/p4") or gitBranchExists("origin/p4/master")
 
-def p4ChangesForPaths(depotPaths, changeRange):
+
+def p4ParseNumericChangeRange(parts):
+    changeStart = int(parts[0][1:])
+    if parts[1] == '#head':
+        changeEnd = p4_last_change()
+    else:
+        changeEnd = int(parts[1])
+
+    return (changeStart, changeEnd)
+
+def chooseBlockSize(blockSize):
+    if blockSize:
+        return blockSize
+    else:
+        return defaultBlockSize
+
+def p4ChangesForPaths(depotPaths, changeRange, requestedBlockSize):
     assert depotPaths
-    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
+    # Parse the change range into start and end. Try to find integer
+    # revision ranges as these can be broken up into blocks to avoid
+    # hitting server-side limits (maxrows, maxscanresults). But if
+    # that doesn't work, fall back to using the raw revision specifier
+    # strings, without using block mode.
+
+    if changeRange is None or changeRange == '':
+        changeStart = 1
+        changeEnd = p4_last_change()
+        block_size = chooseBlockSize(requestedBlockSize)
+    else:
+        parts = changeRange.split(',')
+        assert len(parts) == 2
+        try:
+            (changeStart, changeEnd) = p4ParseNumericChangeRange(parts)
+            block_size = chooseBlockSize(requestedBlockSize)
+        except ValueError:
+            changeStart = parts[0][1:]
+            changeEnd = parts[1]
+            if requestedBlockSize:
+                die("cannot use --changes-block-size with non-numeric revisions")
+            block_size = None
+
+    changes = set()
+
+    # Retrieve changes a block at a time, to prevent running
+    # into a MaxResults/MaxScanRows error from the server. If
+    # we _do_ hit one of those errors, turn down the block size
+
+    while True:
+        cmd = ['changes']
+
+        if block_size:
+            end = min(changeEnd, changeStart + block_size)
+            revisionRange = "%d,%d" % (changeStart, end)
+        else:
+            revisionRange = "%s,%s" % (changeStart, changeEnd)
+
+        for p in depotPaths:
+            cmd += ["%s...@%s" % (p, revisionRange)]
+
+        # fetch the changes
+        try:
+            result = p4CmdList(cmd, errors_as_exceptions=True)
+        except P4RequestSizeException as e:
+            if not block_size:
+                block_size = e.limit
+            elif block_size > e.limit:
+                block_size = e.limit
+            else:
+                block_size = max(2, block_size // 2)
+
+            if verbose: print("block size error, retrying with block size {0}".format(block_size))
+            continue
+        except P4Exception as e:
+            die('Error retrieving changes description ({0})'.format(e.p4ExitCode))
+
+        # Insert changes in chronological order
+        for entry in reversed(result):
+            if 'change' not in entry:
+                continue
+            changes.add(int(entry['change']))
+
+        if not block_size:
+            break
 
-    changelist = changes.keys()
-    changelist.sort()
-    return changelist
+        if end >= changeEnd:
+            break
+
+        changeStart = end + 1
+
+    changes = sorted(changes)
+    return changes
 
 def p4PathStartsWith(path, prefix):
     # This method tries to remedy a potential mixed-case issue:
@@ -629,8 +1179,7 @@ def p4PathStartsWith(path, prefix):
     #
     # we may or may not have a problem. If you have core.ignorecase=true,
     # we treat DirA and dira as the same directory
-    ignorecase = gitConfig("core.ignorecase", "--bool") == "true"
-    if ignorecase:
+    if gitConfigBool("core.ignorecase"):
         return path.lower().startswith(prefix.lower())
     return path.startswith(prefix)
 
@@ -646,11 +1195,14 @@ def getClientSpec():
     # 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()
+    view = View(client_name)
 
     # append the lines, in order, to the view
     for view_num in range(len(view_keys)):
@@ -700,14 +1252,216 @@ def wildcard_encode(path):
     return path
 
 def wildcard_present(path):
-    return path.translate(None, "*#@%") != path
+    m = re.search("[*#@%]", path)
+    return m is not None
+
+class LargeFileSystem(object):
+    """Base class for large file system support."""
+
+    def __init__(self, writeToGitStream):
+        self.largeFiles = set()
+        self.writeToGitStream = writeToGitStream
+
+    def generatePointer(self, cloneDestination, contentFile):
+        """Return the content of a pointer file that is stored in Git instead of
+           the actual content."""
+        assert False, "Method 'generatePointer' required in " + self.__class__.__name__
+
+    def pushFile(self, localLargeFile):
+        """Push the actual content which is not stored in the Git repository to
+           a server."""
+        assert False, "Method 'pushFile' required in " + self.__class__.__name__
+
+    def hasLargeFileExtension(self, relPath):
+        return functools.reduce(
+            lambda a, b: a or b,
+            [relPath.endswith('.' + e) for e in gitConfigList('git-p4.largeFileExtensions')],
+            False
+        )
+
+    def generateTempFile(self, contents):
+        contentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=False)
+        for d in contents:
+            contentFile.write(d)
+        contentFile.close()
+        return contentFile.name
+
+    def exceedsLargeFileThreshold(self, relPath, contents):
+        if gitConfigInt('git-p4.largeFileThreshold'):
+            contentsSize = sum(len(d) for d in contents)
+            if contentsSize > gitConfigInt('git-p4.largeFileThreshold'):
+                return True
+        if gitConfigInt('git-p4.largeFileCompressedThreshold'):
+            contentsSize = sum(len(d) for d in contents)
+            if contentsSize <= gitConfigInt('git-p4.largeFileCompressedThreshold'):
+                return False
+            contentTempFile = self.generateTempFile(contents)
+            compressedContentFile = tempfile.NamedTemporaryFile(prefix='git-p4-large-file', delete=True)
+            with zipfile.ZipFile(compressedContentFile, mode='w') as zf:
+                zf.write(contentTempFile, compress_type=zipfile.ZIP_DEFLATED)
+                compressedContentsSize = zf.infolist()[0].compress_size
+            os.remove(contentTempFile)
+            if compressedContentsSize > gitConfigInt('git-p4.largeFileCompressedThreshold'):
+                return True
+        return False
+
+    def addLargeFile(self, relPath):
+        self.largeFiles.add(relPath)
+
+    def removeLargeFile(self, relPath):
+        self.largeFiles.remove(relPath)
+
+    def isLargeFile(self, relPath):
+        return relPath in self.largeFiles
+
+    def processContent(self, git_mode, relPath, contents):
+        """Processes the content of git fast import. This method decides if a
+           file is stored in the large file system and handles all necessary
+           steps."""
+        if self.exceedsLargeFileThreshold(relPath, contents) or self.hasLargeFileExtension(relPath):
+            contentTempFile = self.generateTempFile(contents)
+            (pointer_git_mode, contents, localLargeFile) = self.generatePointer(contentTempFile)
+            if pointer_git_mode:
+                git_mode = pointer_git_mode
+            if localLargeFile:
+                # Move temp file to final location in large file system
+                largeFileDir = os.path.dirname(localLargeFile)
+                if not os.path.isdir(largeFileDir):
+                    os.makedirs(largeFileDir)
+                shutil.move(contentTempFile, localLargeFile)
+                self.addLargeFile(relPath)
+                if gitConfigBool('git-p4.largeFilePush'):
+                    self.pushFile(localLargeFile)
+                if verbose:
+                    sys.stderr.write("%s moved to large file system (%s)\n" % (relPath, localLargeFile))
+        return (git_mode, contents)
+
+class MockLFS(LargeFileSystem):
+    """Mock large file system for testing."""
+
+    def generatePointer(self, contentFile):
+        """The pointer content is the original content prefixed with "pointer-".
+           The local filename of the large file storage is derived from the file content.
+           """
+        with open(contentFile, 'r') as f:
+            content = next(f)
+            gitMode = '100644'
+            pointerContents = 'pointer-' + content
+            localLargeFile = os.path.join(os.getcwd(), '.git', 'mock-storage', 'local', content[:-1])
+            return (gitMode, pointerContents, localLargeFile)
+
+    def pushFile(self, localLargeFile):
+        """The remote filename of the large file storage is the same as the local
+           one but in a different directory.
+           """
+        remotePath = os.path.join(os.path.dirname(localLargeFile), '..', 'remote')
+        if not os.path.exists(remotePath):
+            os.makedirs(remotePath)
+        shutil.copyfile(localLargeFile, os.path.join(remotePath, os.path.basename(localLargeFile)))
+
+class GitLFS(LargeFileSystem):
+    """Git LFS as backend for the git-p4 large file system.
+       See https://git-lfs.github.com/ for details."""
+
+    def __init__(self, *args):
+        LargeFileSystem.__init__(self, *args)
+        self.baseGitAttributes = []
+
+    def generatePointer(self, contentFile):
+        """Generate a Git LFS pointer for the content. Return LFS Pointer file
+           mode and content which is stored in the Git repository instead of
+           the actual content. Return also the new location of the actual
+           content.
+           """
+        if os.path.getsize(contentFile) == 0:
+            return (None, '', None)
+
+        pointerProcess = subprocess.Popen(
+            ['git', 'lfs', 'pointer', '--file=' + contentFile],
+            stdout=subprocess.PIPE
+        )
+        pointerFile = decode_text_stream(pointerProcess.stdout.read())
+        if pointerProcess.wait():
+            os.remove(contentFile)
+            die('git-lfs pointer command failed. Did you install the extension?')
+
+        # Git LFS removed the preamble in the output of the 'pointer' command
+        # starting from version 1.2.0. Check for the preamble here to support
+        # earlier versions.
+        # c.f. https://github.com/github/git-lfs/commit/da2935d9a739592bc775c98d8ef4df9c72ea3b43
+        if pointerFile.startswith('Git LFS pointer for'):
+            pointerFile = re.sub(r'Git LFS pointer for.*\n\n', '', pointerFile)
+
+        oid = re.search(r'^oid \w+:(\w+)', pointerFile, re.MULTILINE).group(1)
+        # if someone use external lfs.storage ( not in local repo git )
+        lfs_path = gitConfig('lfs.storage')
+        if not lfs_path:
+            lfs_path = 'lfs'
+        if not os.path.isabs(lfs_path):
+            lfs_path = os.path.join(os.getcwd(), '.git', lfs_path)
+        localLargeFile = os.path.join(
+            lfs_path,
+            'objects', oid[:2], oid[2:4],
+            oid,
+        )
+        # LFS Spec states that pointer files should not have the executable bit set.
+        gitMode = '100644'
+        return (gitMode, pointerFile, localLargeFile)
+
+    def pushFile(self, localLargeFile):
+        uploadProcess = subprocess.Popen(
+            ['git', 'lfs', 'push', '--object-id', 'origin', os.path.basename(localLargeFile)]
+        )
+        if uploadProcess.wait():
+            die('git-lfs push command failed. Did you define a remote?')
+
+    def generateGitAttributes(self):
+        return (
+            self.baseGitAttributes +
+            [
+                '\n',
+                '#\n',
+                '# Git LFS (see https://git-lfs.github.com/)\n',
+                '#\n',
+            ] +
+            ['*.' + f.replace(' ', '[[:space:]]') + ' filter=lfs diff=lfs merge=lfs -text\n'
+                for f in sorted(gitConfigList('git-p4.largeFileExtensions'))
+            ] +
+            ['/' + f.replace(' ', '[[:space:]]') + ' filter=lfs diff=lfs merge=lfs -text\n'
+                for f in sorted(self.largeFiles) if not self.hasLargeFileExtension(f)
+            ]
+        )
+
+    def addLargeFile(self, relPath):
+        LargeFileSystem.addLargeFile(self, relPath)
+        self.writeToGitStream('100644', '.gitattributes', self.generateGitAttributes())
+
+    def removeLargeFile(self, relPath):
+        LargeFileSystem.removeLargeFile(self, relPath)
+        self.writeToGitStream('100644', '.gitattributes', self.generateGitAttributes())
+
+    def processContent(self, git_mode, relPath, contents):
+        if relPath == '.gitattributes':
+            self.baseGitAttributes = contents
+            return (git_mode, self.generateGitAttributes())
+        else:
+            return LargeFileSystem.processContent(self, git_mode, relPath, contents)
 
 class Command:
+    delete_actions = ( "delete", "move/delete", "purge" )
+    add_actions = ( "add", "branch", "move/add" )
+
     def __init__(self):
         self.usage = "usage: %prog [options]"
         self.needsGit = True
         self.verbose = False
 
+    # This is required for the "append" update_shelve 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)
+
 class P4UserMap:
     def __init__(self):
         self.userMapFromPerforceServer = False
@@ -719,7 +1473,7 @@ class P4UserMap:
 
         results = p4CmdList("user -o")
         for r in results:
-            if r.has_key('User'):
+            if 'User' in r:
                 self.myP4UserId = r['User']
                 return r['User']
         die("Could not find your p4 user id")
@@ -743,24 +1497,33 @@ class P4UserMap:
         self.emails = {}
 
         for output in p4CmdList("users"):
-            if not output.has_key("User"):
+            if "User" not in output:
                 continue
             self.users[output["User"]] = output["FullName"] + " <" + output["Email"] + ">"
             self.emails[output["Email"]] = output["User"]
 
+        mapUserConfigRegex = re.compile(r"^\s*(\S+)\s*=\s*(.+)\s*<(\S+)>\s*$", re.VERBOSE)
+        for mapUserConfig in gitConfigList("git-p4.mapUser"):
+            mapUser = mapUserConfigRegex.findall(mapUserConfig)
+            if mapUser and len(mapUser[0]) == 3:
+                user = mapUser[0][0]
+                fullname = mapUser[0][1]
+                email = mapUser[0][2]
+                self.users[user] = fullname + " <" + email + ">"
+                self.emails[email] = user
 
         s = ''
         for (key, val) in self.users.items():
             s += "%s\t%s\n" % (key.expandtabs(1), val.expandtabs(1))
 
-        open(self.getUserCacheFilename(), "wb").write(s)
+        open(self.getUserCacheFilename(), 'w').write(s)
         self.userMapFromPerforceServer = True
 
     def loadUserMapFromCache(self):
         self.users = {}
         self.userMapFromPerforceServer = False
         try:
-            cache = open(self.getUserCacheFilename(), "rb")
+            cache = open(self.getUserCacheFilename(), 'r')
             lines = cache.readlines()
             cache.close()
             for line in lines:
@@ -779,9 +1542,9 @@ class P4Debug(Command):
     def run(self, args):
         j = 0
         for output in p4CmdList(args):
-            print 'Element: %d' % j
+            print('Element: %d' % j)
             j += 1
-            print output
+            print(output)
         return True
 
 class P4RollBack(Command):
@@ -822,14 +1585,14 @@ class P4RollBack(Command):
 
                 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)
+                    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)
+                        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)
@@ -839,7 +1602,7 @@ class P4RollBack(Command):
                     change = settings['change']
 
                 if changed:
-                    print "%s rewound to %s" % (ref, change)
+                    print("%s rewound to %s" % (ref, change))
 
         return True
 
@@ -859,19 +1622,76 @@ class P4Submit(Command, P4UserMap):
                 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)
+                                     choices=self.conflict_behavior_choices),
+                optparse.make_option("--branch", dest="branch"),
+                optparse.make_option("--shelve", dest="shelve", action="store_true",
+                                     help="Shelve instead of submit. Shelved files are reverted, "
+                                     "restoring the workspace to the state before the shelve"),
+                optparse.make_option("--update-shelve", dest="update_shelve", action="append", type="int",
+                                     metavar="CHANGELIST",
+                                     help="update an existing shelved changelist, implies --shelve, "
+                                           "repeat in-order for multiple shelved changelists"),
+                optparse.make_option("--commit", dest="commit", metavar="COMMIT",
+                                     help="submit only the specified commit(s), one commit or xxx..xxx"),
+                optparse.make_option("--disable-rebase", dest="disable_rebase", action="store_true",
+                                     help="Disable rebase after submit is completed. Can be useful if you "
+                                     "work from a local git branch that is not master"),
+                optparse.make_option("--disable-p4sync", dest="disable_p4sync", action="store_true",
+                                     help="Skip Perforce sync of p4/master after submit or shelve"),
+                optparse.make_option("--no-verify", dest="no_verify", action="store_true",
+                                     help="Bypass p4-pre-submit and p4-changelist hooks"),
         ]
-        self.description = "Submit changes from git to the perforce depot."
+        self.description = """Submit changes from git to the perforce depot.\n
+    The `p4-pre-submit` hook is executed if it exists and is executable. It
+    can be bypassed with the `--no-verify` command line option. The hook takes
+    no parameters and nothing from standard input. Exiting with a non-zero status
+    from this script prevents `git-p4 submit` from launching.
+
+    One usage scenario is to run unit tests in the hook.
+
+    The `p4-prepare-changelist` hook is executed right after preparing the default
+    changelist message and before the editor is started. It takes one parameter,
+    the name of the file that contains the changelist text. Exiting with a non-zero
+    status from the script will abort the process.
+
+    The purpose of the hook is to edit the message file in place, and it is not
+    supressed by the `--no-verify` option. This hook is called even if
+    `--prepare-p4-only` is set.
+
+    The `p4-changelist` hook is executed after the changelist message has been
+    edited by the user. It can be bypassed with the `--no-verify` option. It
+    takes a single parameter, the name of the file that holds the proposed
+    changelist text. Exiting with a non-zero status causes the command to abort.
+
+    The hook is allowed to edit the changelist file and can be used to normalize
+    the text into some project standard format. It can also be used to refuse the
+    Submit after inspect the message file.
+
+    The `p4-post-changelist` hook is invoked after the submit has successfully
+    occurred in P4. It takes no parameters and is meant primarily for notification
+    and cannot affect the outcome of the git p4 submit action.
+    """
+
         self.usage += " [name of git branch to submit into perforce depot]"
         self.origin = ""
         self.detectRenames = False
-        self.preserveUser = gitConfig("git-p4.preserveUser").lower() == "true"
+        self.preserveUser = gitConfigBool("git-p4.preserveUser")
         self.dry_run = False
+        self.shelve = False
+        self.update_shelve = list()
+        self.commit = ""
+        self.disable_rebase = gitConfigBool("git-p4.disableRebase")
+        self.disable_p4sync = gitConfigBool("git-p4.disableP4Sync")
         self.prepare_p4_only = False
         self.conflict_behavior = None
         self.isWindows = (platform.system() == "Windows")
         self.exportLabels = False
-        self.p4HasMoveCommand = p4_has_command("move")
+        self.p4HasMoveCommand = p4_has_move_command()
+        self.branch = None
+        self.no_verify = False
+
+        if gitConfig('git-p4.largeFileSystem'):
+            die("Large file system not supported for git-p4 submit command. Please remove it from config.")
 
     def check(self):
         if len(p4CmdList("opened ...")) > 0:
@@ -951,17 +1771,18 @@ class P4Submit(Command, P4UserMap):
         except:
             # cleanup our temporary file
             os.unlink(outFileName)
-            print "Failed to strip RCS keywords in %s" % file
+            print("Failed to strip RCS keywords in %s" % file)
             raise
 
-        print "Patched up RCS keywords in %s" % file
+        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' %s" % id)
+        gitEmail = read_pipe(["git", "log", "--max-count=1",
+                              "--format=%ae", id])
         gitEmail = gitEmail.strip()
-        if not self.emails.has_key(gitEmail):
+        if gitEmail not in self.emails:
             return (None,gitEmail)
         else:
             return (self.emails[gitEmail],gitEmail)
@@ -972,8 +1793,8 @@ class P4Submit(Command, P4UserMap):
             (user,email) = self.p4UserForCommit(id)
             if not user:
                 msg = "Cannot find p4 user for email %s in commit %s." % (email, id)
-                if gitConfig('git-p4.allowMissingP4Users').lower() == "true":
-                    print "%s" % msg
+                if gitConfigBool("git-p4.allowMissingP4Users"):
+                    print("%s" % msg)
                 else:
                     die("Error: %s\nSet git-p4.allowMissingP4Users to true to allow this." % msg)
 
@@ -985,14 +1806,14 @@ class P4Submit(Command, P4UserMap):
         results = p4CmdList("client -o")        # find the current client
         client = None
         for r in results:
-            if r.has_key('Client'):
+            if 'Client' in r:
                 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'):
+            if 'change' in r:
                 return r['change']
         die("Could not get changelist number for last submit - cannot patch up user details")
 
@@ -1006,14 +1827,15 @@ class P4Submit(Command, P4UserMap):
         c = changes[0]
         if c['User'] == newUser: return   # nothing to do
         c['User'] = newUser
-        input = marshal.dumps(c)
+        # p4 does not understand format version 3 and above
+        input = marshal.dumps(c, 2)
 
         result = p4CmdList("change -f -i", stdin=input)
         for r in result:
-            if r.has_key('code'):
+            if 'code' in r:
                 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'):
+            if 'data' in r:
                 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))
@@ -1023,14 +1845,14 @@ class P4Submit(Command, P4UserMap):
         # which are required to modify changelists.
         results = p4CmdList(["protects", self.depotPath])
         for r in results:
-            if r.has_key('perm'):
+            if 'perm' in r:
                 if r['perm'] == 'admin':
                     return 1
                 if r['perm'] == 'super':
                     return 1
         return 0
 
-    def prepareSubmitTemplate(self):
+    def prepareSubmitTemplate(self, changelist=None):
         """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.
@@ -1038,28 +1860,64 @@ class P4Submit(Command, P4UserMap):
            Remove lines in the Files section that show changes to files
            outside the depot path we're committing into."""
 
-        template = ""
+        [upstream, settings] = findUpstreamBranchPoint()
+
+        template = """\
+# A Perforce Change Specification.
+#
+#  Change:      The change number. 'new' on a new changelist.
+#  Date:        The date this specification was last modified.
+#  Client:      The client on which the changelist was created.  Read-only.
+#  User:        The user who created the changelist.
+#  Status:      Either 'pending' or 'submitted'. Read-only.
+#  Type:        Either 'public' or 'restricted'. Default is 'public'.
+#  Description: Comments about the changelist.  Required.
+#  Jobs:        What opened jobs are to be closed by this changelist.
+#               You may delete jobs from this list.  (New changelists only.)
+#  Files:       What opened files from the default changelist are to be added
+#               to this changelist.  You may delete files from this list.
+#               (New changelists only.)
+"""
+        files_list = []
         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
+        change_entry = None
+        args = ['change', '-o']
+        if changelist:
+            args.append(str(changelist))
+        for entry in p4CmdList(args):
+            if 'code' not in entry:
+                continue
+            if entry['code'] == 'stat':
+                change_entry = entry
+                break
+        if not change_entry:
+            die('Failed to decode output of p4 change -o')
+        for key, value in change_entry.items():
+            if key.startswith('File'):
+                if 'depot-paths' in settings:
+                    if not [p for p in settings['depot-paths']
+                            if p4PathStartsWith(value, p)]:
+                        continue
                 else:
-                    inFilesSection = False
-            else:
-                if line.startswith("Files:"):
-                    inFilesSection = True
-
-            template += line
-
+                    if not p4PathStartsWith(value, self.depotPath):
+                        continue
+                files_list.append(value)
+                continue
+        # Output in the order expected by prepareLogMessage
+        for key in ['Change', 'Client', 'User', 'Status', 'Description', 'Jobs']:
+            if key not in change_entry:
+                continue
+            template += '\n'
+            template += key + ':'
+            if key == 'Description':
+                template += '\n'
+            for field_line in change_entry[key].splitlines():
+                template += '\t'+field_line+'\n'
+        if len(files_list) > 0:
+            template += '\n'
+            template += 'Files:\n'
+        for path in files_list:
+            template += '\t'+path+'\n'
         return template
 
     def edit_template(self, template_file):
@@ -1067,7 +1925,7 @@ class P4Submit(Command, P4UserMap):
            message.  Return true if okay to continue with the submit."""
 
         # if configured to skip the editing part, just submit
-        if gitConfig("git-p4.skipSubmitEdit") == "true":
+        if gitConfigBool("git-p4.skipSubmitEdit"):
             return True
 
         # look at the modification time, to check later if the user saved
@@ -1075,47 +1933,80 @@ class P4Submit(Command, P4UserMap):
         mtime = os.stat(template_file).st_mtime
 
         # invoke the editor
-        if os.environ.has_key("P4EDITOR") and (os.environ.get("P4EDITOR") != ""):
+        if "P4EDITOR" in os.environ and (os.environ.get("P4EDITOR") != ""):
             editor = os.environ.get("P4EDITOR")
         else:
             editor = read_pipe("git var GIT_EDITOR").strip()
-        system(editor + " " + template_file)
+        system(["sh", "-c", ('%s "$@"' % editor), 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 gitConfig("git-p4.skipSubmitEditCheck") == "true":
+        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
+        response = prompt("Submit template unchanged. Submit anyway? [y]es, [n]o (skip this patch) ")
+        if response == 'y':
+            return True
+        if response == 'n':
+            return False
+
+    def get_diff_description(self, editedFiles, filesToAdd, symlinks):
+        # diff
+        if "P4DIFF" in os.environ:
+            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
+
+            is_link = os.path.islink(newFile)
+            expect_link = newFile in symlinks
+
+            if is_link and expect_link:
+                newdiff += "+%s\n" % os.readlink(newFile)
+            else:
+                f = open(newFile, "r")
+                for line in f.readlines():
+                    newdiff += "+" + line
+                f.close()
+
+        return (diff + newdiff).replace('\r\n', '\n')
 
     def applyCommit(self, id):
         """Apply one commit, return True if it succeeded."""
 
-        print "Applying", read_pipe(["git", "show", "-s",
-                                     "--format=format:%h %s", id])
+        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()
+        filesToChangeType = set()
         filesToDelete = set()
         editedFiles = set()
         pureRenameCopy = set()
+        symlinks = set()
         filesToChangeExecBit = {}
+        all_files = list()
 
         for line in diff:
             diff = parseDiffTreeEntry(line)
             modifier = diff['status']
             path = diff['src']
+            all_files.append(path)
+
             if modifier == "M":
                 p4_edit(path)
                 if isModeExecChanged(diff['src_mode'], diff['dst_mode']):
@@ -1126,12 +2017,18 @@ class P4Submit(Command, P4UserMap):
                 filesToChangeExecBit[path] = diff['dst_mode']
                 if path in filesToDelete:
                     filesToDelete.remove(path)
+
+                dst_mode = int(diff['dst_mode'], 8)
+                if dst_mode == 0o120000:
+                    symlinks.add(path)
+
             elif modifier == "D":
                 filesToDelete.add(path)
                 if path in filesToAdd:
                     filesToAdd.remove(path)
             elif modifier == "C":
                 src, dest = diff['src'], diff['dst']
+                all_files.append(dest)
                 p4_integrate(src, dest)
                 pureRenameCopy.add(dest)
                 if diff['src_sha1'] != diff['dst_sha1']:
@@ -1141,10 +2038,14 @@ class P4Submit(Command, P4UserMap):
                     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']
+                all_files.append(dest)
                 if self.p4HasMoveCommand:
                     p4_edit(src)        # src must be open before move
                     p4_move(src, dest)  # opens for (move/delete, move/add)
@@ -1159,26 +2060,33 @@ class P4Submit(Command, P4UserMap):
                         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)
+            elif modifier == "T":
+                filesToChangeType.add(path)
             else:
                 die("unknown modifier %s for %s" % (modifier, path))
 
-        diffcmd = "git format-patch -k --stdout \"%s^\"..\"%s\"" % (id, id)
+        diffcmd = "git diff-tree --full-index -p \"%s\"" % (id)
         patchcmd = diffcmd + " | git apply "
         tryPatchCmd = patchcmd + "--check -"
         applyPatchCmd = patchcmd + "--check --apply -"
         patch_succeeded = True
 
+        if verbose:
+            print("TryPatch: %s" % tryPatchCmd)
+
         if os.system(tryPatchCmd) != 0:
             fixed_rcs_keywords = False
             patch_succeeded = False
-            print "Unfortunately applying the change failed!"
+            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 gitConfig("git-p4.attemptRCSCleanup","--bool") == "true":
+            if gitConfigBool("git-p4.attemptRCSCleanup"):
                 file = None
                 pattern = None
                 kwfiles = {}
@@ -1192,20 +2100,25 @@ class P4Submit(Command, P4UserMap):
                         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)
+                                    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)
+                        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"
+                print("Retrying the patch with RCS keywords cleaned up")
                 if os.system(tryPatchCmd) == 0:
                     patch_succeeded = True
+                    print("Patch succeesed this time with RCS keywords cleaned")
 
         if not patch_succeeded:
             for f in editedFiles:
@@ -1217,6 +2130,8 @@ class P4Submit(Command, P4UserMap):
         #
         system(applyPatchCmd)
 
+        for f in filesToChangeType:
+            p4_edit(f, "-t", "auto")
         for f in filesToAdd:
             p4_add(f)
         for f in filesToDelete:
@@ -1228,6 +2143,11 @@ class P4Submit(Command, P4UserMap):
             mode = filesToChangeExecBit[f]
             setP4ExecBit(f, mode)
 
+        update_shelve = 0
+        if len(self.update_shelve) > 0:
+            update_shelve = self.update_shelve.pop(0)
+            p4_reopen_in_change(update_shelve, all_files)
+
         #
         # Build p4 change description, starting with the contents
         # of the git commit message.
@@ -1236,7 +2156,7 @@ class P4Submit(Command, P4UserMap):
         logMessage = logMessage.strip()
         (logMessage, jobs) = self.separate_jobs_from_description(logMessage)
 
-        template = self.prepareSubmitTemplate()
+        template = self.prepareSubmitTemplate(update_shelve)
         submitTemplate = self.prepareLogMessage(template, logMessage, jobs)
 
         if self.preserveUser:
@@ -1248,112 +2168,124 @@ class P4Submit(Command, P4UserMap):
             submitTemplate += "######## Variable git-p4.skipUserNameCheck hides this message.\n"
 
         separatorLine = "######## everything below this line is just the diff #######\n"
+        if not self.prepare_p4_only:
+            submitTemplate += separatorLine
+            submitTemplate += self.get_diff_description(editedFiles, filesToAdd, symlinks)
 
-        # 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+")
+        tmpFile = os.fdopen(handle, "w+b")
         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.write(encode_text_stream(submitTemplate))
         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
+        submitted = False
 
-        #
-        # 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")
+        try:
+            # Allow the hook to edit the changelist text before presenting it
+            # to the user.
+            if not run_git_hook("p4-prepare-changelist", [fileName]):
+                return False
 
-        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)
+            if self.prepare_p4_only:
+                #
+                # Leave the p4 tree prepared, and the submit template around
+                # and let the user decide what to do next
+                #
+                submitted = True
+                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("")
+                sys.stdout.flush()
+                return True
 
-        os.remove(fileName)
-        return ret
+            if self.edit_template(fileName):
+                if not self.no_verify:
+                    if not run_git_hook("p4-changelist", [fileName]):
+                        print("The p4-changelist hook failed.")
+                        sys.stdout.flush()
+                        return False
+
+                # read the edited message and submit
+                tmpFile = open(fileName, "rb")
+                message = decode_text_stream(tmpFile.read())
+                tmpFile.close()
+                if self.isWindows:
+                    message = message.replace("\r\n", "\n")
+                if message.find(separatorLine) != -1:
+                    submitTemplate = message[:message.index(separatorLine)]
+                else:
+                    submitTemplate = message
+
+                if len(submitTemplate.strip()) == 0:
+                    print("Changelist is empty, aborting this changelist.")
+                    sys.stdout.flush()
+                    return False
+
+                if update_shelve:
+                    p4_write_pipe(['shelve', '-r', '-i'], submitTemplate)
+                elif self.shelve:
+                    p4_write_pipe(['shelve', '-i'], submitTemplate)
+                else:
+                    p4_write_pipe(['submit', '-i'], submitTemplate)
+                    # 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")
+
+                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)
+
+                submitted = True
+
+                run_git_hook("p4-post-changelist")
+        finally:
+            # Revert changes if we skip this patch
+            if not submitted or self.shelve:
+                if self.shelve:
+                    print ("Reverting shelved files.")
+                else:
+                    print ("Submission cancelled, undoing p4 changes.")
+                sys.stdout.flush()
+                for f in editedFiles | filesToDelete:
+                    p4_revert(f)
+                for f in filesToAdd:
+                    p4_revert(f)
+                    os.remove(f)
+
+            if not self.prepare_p4_only:
+                os.remove(fileName)
+        return submitted
 
     # Export git tags as p4 labels. Create a p4 label and then tag
     # with that.
@@ -1367,17 +2299,17 @@ class P4Submit(Command, P4UserMap):
 
             if not m.match(name):
                 if verbose:
-                    print "tag %s does not match regexp %s" % (name, validLabelRegexp)
+                    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'):
+            if 'change' not in values:
                 # a tag pointing to something not sent to p4; ignore
                 if verbose:
-                    print "git tag %s does not give a p4 commit" % name
+                    print("git tag %s does not give a p4 commit" % name)
                 continue
             else:
                 changelist = values['change']
@@ -1408,29 +2340,27 @@ class P4Submit(Command, P4UserMap):
             for b in body:
                 labelTemplate += "\t" + b + "\n"
             labelTemplate += "View:\n"
-            for mapping in clientSpec.mappings:
-                labelTemplate += "\t%s\n" % mapping.depot_side.path
+            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
+                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
+                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" % (mapping.depot_side.path, changelist) for mapping in clientSpec.mappings])
+                          ["%s@%s" % (depot_side, changelist) for depot_side in clientSpec.mappings])
 
                 if verbose:
-                    print "created p4 label for tag %s" % name
+                    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):
@@ -1438,15 +2368,23 @@ class P4Submit(Command, P4UserMap):
         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)
+        for i in self.update_shelve:
+            if i <= 0:
+                sys.exit("invalid changelist %d" % i)
+
+        if self.master:
+            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 len(self.update_shelve) > 0:
+            self.shelve = True
+
         if self.preserveUser:
             if not self.canChangeChangelists():
                 die("Cannot preserve user names without p4 super-user or admin permissions")
@@ -1462,19 +2400,22 @@ class P4Submit(Command, P4UserMap):
             self.conflict_behavior = val
 
         if self.verbose:
-            print "Origin branch is " + self.origin
+            print("Origin branch is " + self.origin)
 
         if len(self.depotPath) == 0:
-            print "Internal error: cannot locate perforce depot path from existing branches"
+            print("Internal error: cannot locate perforce depot path from existing branches")
             sys.exit(128)
 
         self.useClientSpec = False
-        if gitConfig("git-p4.useclientspec", "--bool") == "true":
+        if gitConfigBool("git-p4.useclientspec"):
             self.useClientSpec = True
         if self.useClientSpec:
             self.clientSpecDirs = getClientSpec()
 
-        if self.useClientSpec:
+        # Check for the existence of P4 branches
+        branchesDetected = (len(p4BranchesInGit().keys()) > 1)
+
+        if self.useClientSpec and not branchesDetected:
             # all files are relative to the client spec
             self.clientPath = getClientRoot()
         else:
@@ -1483,7 +2424,7 @@ class P4Submit(Command, P4UserMap):
         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)
+        print("Perforce checkout for depot path %s located at %s" % (self.depotPath, self.clientPath))
         self.oldWorkingDirectory = os.getcwd()
 
         # ensure the clientPath exists
@@ -1492,11 +2433,11 @@ class P4Submit(Command, P4UserMap):
             new_client_dir = True
             os.makedirs(self.clientPath)
 
-        chdir(self.clientPath)
+        chdir(self.clientPath, is_client_path=True)
         if self.dry_run:
-            print "Would synchronize p4 checkout in %s" % self.clientPath
+            print("Would synchronize p4 checkout in %s" % self.clientPath)
         else:
-            print "Synchronizing p4 checkout..."
+            print("Synchronizing p4 checkout...")
             if new_client_dir:
                 # old one was destroyed, and maybe nobody told p4
                 p4_sync("...", "-f")
@@ -1505,11 +2446,25 @@ class P4Submit(Command, P4UserMap):
         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.master:
+            committish = self.master
+        else:
+            committish = 'HEAD'
+
+        if self.commit != "":
+            if self.commit.find("..") != -1:
+                limits_ish = self.commit.split("..")
+                for line in read_pipe_lines(["git", "rev-list", "--no-merges", "%s..%s" % (limits_ish[0], limits_ish[1])]):
+                    commits.append(line.strip())
+                commits.reverse()
+            else:
+                commits.append(self.commit)
+        else:
+            for line in read_pipe_lines(["git", "rev-list", "--no-merges", "%s..%s" % (self.origin, committish)]):
+                commits.append(line.strip())
+            commits.reverse()
 
-        if self.preserveUser or (gitConfig("git-p4.skipUserNameCheck") == "true"):
+        if self.preserveUser or gitConfigBool("git-p4.skipUserNameCheck"):
             self.checkAuthorship = False
         else:
             self.checkAuthorship = True
@@ -1545,89 +2500,104 @@ class P4Submit(Command, P4UserMap):
         else:
             self.diffOpts += " -C%s" % detectCopies
 
-        if gitConfig("git-p4.detectCopiesHarder", "--bool") == "true":
+        if gitConfigBool("git-p4.detectCopiesHarder"):
             self.diffOpts += " --find-copies-harder"
 
+        num_shelves = len(self.update_shelve)
+        if num_shelves > 0 and num_shelves != len(commits):
+            sys.exit("number of commits (%d) must match number of shelved changelist (%d)" %
+                     (len(commits), num_shelves))
+
+        if not self.no_verify:
+            try:
+                if not run_git_hook("p4-pre-submit"):
+                    print("\nThe p4-pre-submit hook failed, aborting the submit.\n\nYou can skip " \
+                        "this pre-submission check by adding\nthe command line option '--no-verify', " \
+                        "however,\nthis will also skip the p4-changelist hook as well.")
+                    sys.exit(1)
+            except Exception as e:
+                print("\nThe p4-pre-submit hook failed, aborting the submit.\n\nThe hook failed "\
+                    "with the error '{0}'".format(e.message) )
+                sys.exit(1)
+
         #
         # 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"
+            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])
+                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"
+                if self.prepare_p4_only:
+                    if i < last:
+                        print("Processing only the first commit due to option" \
+                                " --prepare-p4-only")
                     break
+            else:
                 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:
+                    # prompt for what to do, or use the option/variable
+                    if self.conflict_behavior == "ask":
+                        print("What do you want to do?")
+                        response = prompt("[s]kip this commit but apply the rest, or [q]uit? ")
+                    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 == "s":
+                        print("Skipping this commit, but applying the rest")
+                    if response == "q":
+                        print("Quitting")
                         break
 
         chdir(self.oldWorkingDirectory)
-
+        shelved_applied = "shelved" if self.shelve else "applied"
         if self.dry_run:
             pass
         elif self.prepare_p4_only:
             pass
         elif len(commits) == len(applied):
-            print "All commits applied!"
+            print("All commits {0}!".format(shelved_applied))
 
             sync = P4Sync()
-            sync.run([])
+            if self.branch:
+                sync.branch = self.branch
+            if self.disable_p4sync:
+                sync.sync_origin_only()
+            else:
+                sync.run([])
 
-            rebase = P4Rebase()
-            rebase.rebase()
+                if not self.disable_rebase:
+                    rebase = P4Rebase()
+                    rebase.rebase()
 
         else:
             if len(applied) == 0:
-                print "No commits applied."
+                print("No commits {0}.".format(shelved_applied))
             else:
-                print "Applied only the commits marked with '*':"
+                print("{0} only the commits marked with '*':".format(shelved_applied.capitalize()))
                 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."
+                    print(star, read_pipe(["git", "show", "-s",
+                                           "--format=format:%h %s",  c]))
+                print("You will have to do 'git p4 sync' and rebase.")
 
-        if gitConfig("git-p4.exportLabels", "--bool") == "true":
+        if gitConfigBool("git-p4.exportLabels"):
             self.exportLabels = True
 
         if self.exportLabels:
@@ -1637,7 +2607,7 @@ class P4Submit(Command, P4UserMap):
             missingGitTags = gitTags - p4Labels
             self.exportGitTags(missingGitTags)
 
-        # exit with error unless everything applied perfecly
+        # exit with error unless everything applied perfectly
         if len(commits) != len(applied):
                 sys.exit(1)
 
@@ -1647,117 +2617,16 @@ class View(object):
     """Represent a p4 view ("p4 help views"), and map files in a
        repo according to the view."""
 
-    class Path(object):
-        """A depot or client path, possibly containing wildcards.
-           The only one supported is ... at the end, currently.
-           Initialize with the full path, with //depot or //client."""
-
-        def __init__(self, path, is_depot):
-            self.path = path
-            self.is_depot = is_depot
-            self.find_wildcards()
-            # remember the prefix bit, useful for relative mappings
-            m = re.match("(//[^/]+/)", self.path)
-            if not m:
-                die("Path %s does not start with //prefix/" % self.path)
-            prefix = m.group(1)
-            if not self.is_depot:
-                # strip //client/ on client paths
-                self.path = self.path[len(prefix):]
-
-        def find_wildcards(self):
-            """Make sure wildcards are valid, and set up internal
-               variables."""
-
-            self.ends_triple_dot = False
-            # There are three wildcards allowed in p4 views
-            # (see "p4 help views").  This code knows how to
-            # handle "..." (only at the end), but cannot deal with
-            # "%%n" or "*".  Only check the depot_side, as p4 should
-            # validate that the client_side matches too.
-            if re.search(r'%%[1-9]', self.path):
-                die("Can't handle %%n wildcards in view: %s" % self.path)
-            if self.path.find("*") >= 0:
-                die("Can't handle * wildcards in view: %s" % self.path)
-            triple_dot_index = self.path.find("...")
-            if triple_dot_index >= 0:
-                if triple_dot_index != len(self.path) - 3:
-                    die("Can handle only single ... wildcard, at end: %s" %
-                        self.path)
-                self.ends_triple_dot = True
-
-        def ensure_compatible(self, other_path):
-            """Make sure the wildcards agree."""
-            if self.ends_triple_dot != other_path.ends_triple_dot:
-                 die("Both paths must end with ... if either does;\n" +
-                     "paths: %s %s" % (self.path, other_path.path))
-
-        def match_wildcards(self, test_path):
-            """See if this test_path matches us, and fill in the value
-               of the wildcards if so.  Returns a tuple of
-               (True|False, wildcards[]).  For now, only the ... at end
-               is supported, so at most one wildcard."""
-            if self.ends_triple_dot:
-                dotless = self.path[:-3]
-                if test_path.startswith(dotless):
-                    wildcard = test_path[len(dotless):]
-                    return (True, [ wildcard ])
-            else:
-                if test_path == self.path:
-                    return (True, [])
-            return (False, [])
-
-        def match(self, test_path):
-            """Just return if it matches; don't bother with the wildcards."""
-            b, _ = self.match_wildcards(test_path)
-            return b
-
-        def fill_in_wildcards(self, wildcards):
-            """Return the relative path, with the wildcards filled in
-               if there are any."""
-            if self.ends_triple_dot:
-                return self.path[:-3] + wildcards[0]
-            else:
-                return self.path
-
-    class Mapping(object):
-        def __init__(self, depot_side, client_side, overlay, exclude):
-            # depot_side is without the trailing /... if it had one
-            self.depot_side = View.Path(depot_side, is_depot=True)
-            self.client_side = View.Path(client_side, is_depot=False)
-            self.overlay = overlay  # started with "+"
-            self.exclude = exclude  # started with "-"
-            assert not (self.overlay and self.exclude)
-            self.depot_side.ensure_compatible(self.client_side)
-
-        def __str__(self):
-            c = " "
-            if self.overlay:
-                c = "+"
-            if self.exclude:
-                c = "-"
-            return "View.Mapping: %s%s -> %s" % \
-                   (c, self.depot_side.path, self.client_side.path)
-
-        def map_depot_to_client(self, depot_path):
-            """Calculate the client path if using this mapping on the
-               given depot path; does not consider the effect of other
-               mappings in a view.  Even excluded mappings are returned."""
-            matches, wildcards = self.depot_side.match_wildcards(depot_path)
-            if not matches:
-                return ""
-            client_path = self.client_side.fill_in_wildcards(wildcards)
-            return client_path
-
-    #
-    # View methods
-    #
-    def __init__(self):
+    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."""
+           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.
@@ -1785,79 +2654,78 @@ class View(object):
             depot_side = view_line[0:space_index]
             rhs_index = space_index + 1
 
-        if view_line[rhs_index] == '"':
-            # Second word is double quoted.  Make sure there is a
-            # double quote at the end too.
-            if not view_line.endswith('"'):
-                die("View line with rhs quote should end with one: %s" %
-                    view_line)
-            # skip the quotes
-            client_side = view_line[rhs_index+1:-1]
-        else:
-            client_side = view_line[rhs_index:]
-
         # prefix + means overlay on previous mapping
-        overlay = False
         if depot_side.startswith("+"):
-            overlay = True
             depot_side = depot_side[1:]
 
-        # prefix - means exclude this path
+        # prefix - means exclude this path, leave out of mappings
         exclude = False
         if depot_side.startswith("-"):
             exclude = True
             depot_side = depot_side[1:]
 
-        m = View.Mapping(depot_side, client_side, overlay, exclude)
-        self.mappings.append(m)
+        if not exclude:
+            self.mappings.append(depot_side)
+
+    def convert_client_path(self, clientFile):
+        # chop off //client/ part to make it relative
+        if not decode_path(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 decode_path(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 in 'p4 where' output")
+            if "unmap" in res:
+                # it will list all of them, but only one not unmap-ped
+                continue
+            depot_path = decode_path(res['depotFile'])
+            if gitConfigBool("core.ignorecase"):
+                depot_path = depot_path.lower()
+            self.client_spec_path_cache[depot_path] = self.convert_client_path(res["clientFile"])
+
+        # not found files or unmap files set to ""
+        for depotFile in fileArgs:
+            depotFile = decode_path(depotFile)
+            if gitConfigBool("core.ignorecase"):
+                depotFile = depotFile.lower()
+            if depotFile not in self.client_spec_path_cache:
+                self.client_spec_path_cache[depotFile] = b''
 
     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."""
 
-        paths_filled = []
-        client_path = ""
-
-        # look at later entries first
-        for m in self.mappings[::-1]:
-
-            # see where will this path end up in the client
-            p = m.map_depot_to_client(depot_path)
+        if gitConfigBool("core.ignorecase"):
+            depot_path = depot_path.lower()
 
-            if p == "":
-                # Depot path does not belong in client.  Must remember
-                # this, as previous items should not cause files to
-                # exist in this path either.  Remember that the list is
-                # being walked from the end, which has higher precedence.
-                # Overlap mappings do not exclude previous mappings.
-                if not m.overlay:
-                    paths_filled.append(m.client_side)
-
-            else:
-                # This mapping matched; no need to search any further.
-                # But, the mapping could be rejected if the client path
-                # has already been claimed by an earlier mapping (i.e.
-                # one later in the list, which we are walking backwards).
-                already_mapped_in_client = False
-                for f in paths_filled:
-                    # this is View.Path.match
-                    if f.match(p):
-                        already_mapped_in_client = True
-                        break
-                if not already_mapped_in_client:
-                    # Include this file, unless it is from a line that
-                    # explicitly said to exclude it.
-                    if not m.exclude:
-                        client_path = p
+        if depot_path in self.client_spec_path_cache:
+            return self.client_spec_path_cache[depot_path]
 
-                # a match, even if rejected, always stops the search
-                break
+        die( "Error: %s is not found in client spec path" % depot_path )
+        return ""
 
-        return client_path
+def cloneExcludeCallback(option, opt_str, value, parser):
+    # prepend "/" because the first "/" was consumed as part of the option itself.
+    # ("-//depot/A/..." becomes "/depot/A/..." after option parsing)
+    parser.values.cloneExclude += ["/" + re.sub(r"\.\.\.$", "", value)]
 
 class P4Sync(Command, P4UserMap):
-    delete_actions = ( "delete", "move/delete", "purge" )
 
     def __init__(self):
         Command.__init__(self)
@@ -1871,11 +2739,17 @@ class P4Sync(Command, P4UserMap):
                 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("--max-changes", dest="maxChanges",
+                                     help="Maximum number of changes to import"),
+                optparse.make_option("--changes-block-size", dest="changes_block_size", type="int",
+                                     help="Internal block size to use when iteratively calling p4 changes"),
                 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")
+                                     help="Only sync files that are included in the Perforce Client Spec"),
+                optparse.make_option("-/", dest="cloneExclude",
+                                     action="callback", callback=cloneExcludeCallback, type="string",
+                                     help="exclude depot path"),
         ]
         self.description = """Imports from Perforce into a git repository.\n
     example:
@@ -1897,7 +2771,7 @@ class P4Sync(Command, P4UserMap):
         self.syncWithOrigin = True
         self.importIntoRemotes = True
         self.maxChanges = ""
-        self.isWindows = (platform.system() == "Windows")
+        self.changes_block_size = None
         self.keepRepoPath = False
         self.depotPaths = None
         self.p4BranchesInGit = []
@@ -1906,33 +2780,59 @@ class P4Sync(Command, P4UserMap):
         self.useClientSpec_from_options = False
         self.clientSpecDirs = None
         self.tempBranches = []
-        self.tempBranchLocation = "git-p4-tmp"
+        self.tempBranchLocation = "refs/git-p4-tmp"
+        self.largeFileSystem = None
+        self.suppress_meta_comment = False
+
+        if gitConfig('git-p4.largeFileSystem'):
+            largeFileSystemConstructor = globals()[gitConfig('git-p4.largeFileSystem')]
+            self.largeFileSystem = largeFileSystemConstructor(
+                lambda git_mode, relPath, contents: self.writeToGitStream(git_mode, relPath, contents)
+            )
 
         if gitConfig("git-p4.syncFromOrigin") == "false":
             self.syncWithOrigin = False
 
+        self.depotPaths = []
+        self.changeRange = ""
+        self.previousDepotPaths = []
+        self.hasOrigin = False
+
+        # map from branch depot path to parent branch
+        self.knownBranches = {}
+        self.initialParents = {}
+
+        self.tz = "%+03d%02d" % (- time.timezone / 3600, ((- time.timezone % 3600) / 60))
+        self.labels = {}
+
     # 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")
+        self.gitStream.flush()
         out = self.gitOutput.readline()
         if self.verbose:
-            print "checkpoint finished: " + out
+            print("checkpoint finished: " + out)
+
+    def isPathWanted(self, path):
+        for p in self.cloneExclude:
+            if p.endswith("/"):
+                if p4PathStartsWith(path, p):
+                    return False
+            # "-//depot/file1" without a trailing "/" should only exclude "file1", but not "file111" or "file1_dir/file2"
+            elif path.lower() == p.lower():
+                return False
+        for p in self.depotPaths:
+            if p4PathStartsWith(path, decode_path(p)):
+                return True
+        return False
 
-    def extractFilesFromCommit(self, commit):
-        self.cloneExclude = [re.sub(r"\.\.\.$", "", path)
-                             for path in self.cloneExclude]
+    def extractFilesFromCommit(self, commit, shelved=False, shelved_cl = 0):
         files = []
         fnum = 0
-        while commit.has_key("depotFile%s" % fnum):
+        while "depotFile%s" % fnum in commit:
             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)]
+            found = self.isPathWanted(decode_path(path))
             if not found:
                 fnum = fnum + 1
                 continue
@@ -1942,10 +2842,21 @@ class P4Sync(Command, P4UserMap):
             file["rev"] = commit["rev%s" % fnum]
             file["action"] = commit["action%s" % fnum]
             file["type"] = commit["type%s" % fnum]
+            if shelved:
+                file["shelved_cl"] = int(shelved_cl)
             files.append(file)
             fnum = fnum + 1
         return files
 
+    def extractJobsFromCommit(self, commit):
+        jobs = []
+        jnum = 0
+        while "job%s" % jnum in commit:
+            job = commit["job%s" % jnum]
+            jobs.append(job)
+            jnum = jnum + 1
+        return jobs
+
     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
@@ -1955,10 +2866,10 @@ class P4Sync(Command, P4UserMap):
         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)
+            path = decode_path(self.clientSpecDirs.map_in_client(path))
             if self.detectBranches:
                 for b in self.knownBranches:
-                    if path.startswith(b + "/"):
+                    if p4PathStartsWith(path, b + "/"):
                         path = path[len(b)+1:]
 
         elif self.keepRepoPath:
@@ -1982,18 +2893,22 @@ class P4Sync(Command, P4UserMap):
         """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)]
+        while "depotFile%s" % fnum in commit:
+            raw_path = commit["depotFile%s" % fnum]
+            path = decode_path(raw_path)
+            found = self.isPathWanted(path)
             if not found:
                 fnum = fnum + 1
                 continue
 
             file = {}
-            file["path"] = path
+            file["path"] = raw_path
             file["rev"] = commit["rev%s" % fnum]
             file["action"] = commit["action%s" % fnum]
             file["type"] = commit["type%s" % fnum]
@@ -2002,14 +2917,14 @@ class P4Sync(Command, P4UserMap):
             # 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)
+                relPath = decode_path(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 p4PathStartsWith(relPath, branch + "/"):
                     if branch not in branches:
                         branches[branch] = []
                     branches[branch].append(file)
@@ -2017,13 +2932,39 @@ class P4Sync(Command, P4UserMap):
 
         return branches
 
+    def writeToGitStream(self, gitMode, relPath, contents):
+        self.gitStream.write(encode_text_stream(u'M {} inline {}\n'.format(gitMode, relPath)))
+        self.gitStream.write('data %d\n' % sum(len(d) for d in contents))
+        for d in contents:
+            self.gitStream.write(d)
+        self.gitStream.write('\n')
+
+    def encodeWithUTF8(self, path):
+        try:
+            path.decode('ascii')
+        except:
+            encoding = 'utf8'
+            if gitConfig('git-p4.pathEncoding'):
+                encoding = gitConfig('git-p4.pathEncoding')
+            path = path.decode(encoding, 'replace').encode('utf8', 'replace')
+            if self.verbose:
+                print('Path with non-ASCII characters detected. Used %s to encode: %s ' % (encoding, path))
+        return path
+
     # output one file from the P4 stream
     # - helper for streamP4Files
 
     def streamOneP4File(self, file, contents):
-        relPath = self.stripRepoPath(file['depotFile'], self.branchPrefixes)
+        file_path = file['depotFile']
+        relPath = self.stripRepoPath(decode_path(file_path), self.branchPrefixes)
+
         if verbose:
-            sys.stderr.write("%s\n" % relPath)
+            if 'fileSize' in self.stream_file:
+                size = int(self.stream_file['fileSize'])
+            else:
+                size = 0 # deleted files don't get a fileSize apparently
+            sys.stdout.write('\r%s --> %s (%i MB)\n' % (file_path, relPath, size/1024/1024))
+            sys.stdout.flush()
 
         (type_base, type_mods) = split_p4_type(file["type"])
 
@@ -2032,9 +2973,20 @@ class P4Sync(Command, P4UserMap):
             git_mode = "100755"
         if type_base == "symlink":
             git_mode = "120000"
-            # p4 print on a symlink contains "target\n"; remove the newline
-            data = ''.join(contents)
-            contents = [data[:-1]]
+            # p4 print on a symlink sometimes contains "target\n";
+            # if it does, remove the newline
+            data = ''.join(decode_text_stream(c) for c in contents)
+            if not data:
+                # Some version of p4 allowed creating a symlink that pointed
+                # to nothing.  This causes p4 errors when checking out such
+                # a change, and errors here too.  Work around it by ignoring
+                # the bad symlink; hopefully a future change fixes it.
+                print("\nIgnoring empty symlink in %s" % file_path)
+                return
+            elif data[-1] == '\n':
+                contents = [data[:-1]]
+            else:
+                contents = [data]
 
         if type_base == "utf16":
             # p4 delivers different text in the python output to -G
@@ -2042,8 +2994,22 @@ class P4Sync(Command, P4UserMap):
             # 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.
-            text = p4_read_pipe(['print', '-q', '-o', '-', file['depotFile']])
-            contents = [ text ]
+            #
+            # 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.
+            #
+            try:
+                text = p4_read_pipe(['print', '-q', '-o', '-', '%s@%s' % (decode_path(file['depotFile']), file['change'])], raw=True)
+            except Exception as e:
+                if 'Translation of file content failed' in str(e):
+                    type_base = 'binary'
+                else:
+                    raise e
+            else:
+                if p4_version_string().find('/NT') >= 0:
+                    text = text.replace(b'\r\n', b'\n')
+                contents = [ text ]
 
         if type_base == "apple":
             # Apple filetype files will be streamed as a concatenation of
@@ -2055,49 +3021,68 @@ class P4Sync(Command, P4UserMap):
             # 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']
+            print("\nIgnoring apple filetype file %s" % file['depotFile'])
             return
 
-        # Perhaps windows wants unicode, utf16 newlines translated too;
-        # but this is not doing it.
-        if self.isWindows and type_base == "text":
-            mangled = []
-            for data in contents:
-                data = data.replace("\r\n", "\n")
-                mangled.append(data)
-            contents = mangled
-
         # 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 = ''.join(decode_text_stream(c) for c in contents)
             text = regexp.sub(r'$\1$', text)
             contents = [ text ]
 
-        self.gitStream.write("M %s inline %s\n" % (git_mode, relPath))
+        if self.largeFileSystem:
+            (git_mode, contents) = self.largeFileSystem.processContent(git_mode, relPath, contents)
 
-        # 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")
+        self.writeToGitStream(git_mode, relPath, contents)
 
     def streamOneP4Deletion(self, file):
-        relPath = self.stripRepoPath(file['path'], self.branchPrefixes)
+        relPath = self.stripRepoPath(decode_path(file['path']), self.branchPrefixes)
         if verbose:
-            sys.stderr.write("delete %s\n" % relPath)
-        self.gitStream.write("D %s\n" % relPath)
+            sys.stdout.write("delete %s\n" % relPath)
+            sys.stdout.flush()
+        self.gitStream.write(encode_text_stream(u'D {}\n'.format(relPath)))
+
+        if self.largeFileSystem and self.largeFileSystem.isLargeFile(relPath):
+            self.largeFileSystem.removeLargeFile(relPath)
 
     # handle another chunk of streaming data
     def streamP4FilesCb(self, marshalled):
 
-        if marshalled.has_key('depotFile') and self.stream_have_file_info:
+        # catch p4 errors and complain
+        err = None
+        if "code" in marshalled:
+            if marshalled["code"] == "error":
+                if "data" in marshalled:
+                    err = marshalled["data"].rstrip()
+
+        if not err and 'fileSize' in self.stream_file:
+            required_bytes = int((4 * int(self.stream_file["fileSize"])) - calcDiskFree())
+            if required_bytes > 0:
+                err = 'Not enough space left on %s! Free at least %i MB.' % (
+                    os.getcwd(), required_bytes/1024/1024
+                )
+
+        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 'depotFile' in marshalled 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 = {}
@@ -2108,10 +3093,23 @@ class P4Sync(Command, P4UserMap):
         # 'data' field we need to append to our array
         for k in marshalled.keys():
             if k == 'data':
+                if 'streamContentSize' not in self.stream_file:
+                    self.stream_file['streamContentSize'] = 0
+                self.stream_file['streamContentSize'] += len(marshalled['data'])
                 self.stream_contents.append(marshalled['data'])
             else:
                 self.stream_file[k] = marshalled[k]
 
+        if (verbose and
+            'streamContentSize' in self.stream_file and
+            'fileSize' in self.stream_file and
+            'depotFile' in self.stream_file):
+            size = int(self.stream_file["fileSize"])
+            if size > 0:
+                progress = 100*self.stream_file['streamContentSize']/size
+                sys.stdout.write('\r%s %d%% (%i MB)' % (self.stream_file['depotFile'], progress, int(size/1024/1024)))
+                sys.stdout.flush()
+
         self.stream_have_file_info = True
 
     # Stream directly from "p4 files" into "git fast-import"
@@ -2121,12 +3119,6 @@ class P4Sync(Command, P4UserMap):
         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)
@@ -2146,14 +3138,23 @@ class P4Sync(Command, P4UserMap):
             def streamP4FilesCbSelf(entry):
                 self.streamP4FilesCb(entry)
 
-            fileArgs = ['%s#%s' % (f['path'], f['rev']) for f in filesToRead]
+            fileArgs = []
+            for f in filesToRead:
+                if 'shelved_cl' in f:
+                    # Handle shelved CLs using the "p4 print file@=N" syntax to print
+                    # the contents
+                    fileArg = f['path'] + encode_text_stream('@={}'.format(f['shelved_cl']))
+                else:
+                    fileArg = f['path'] + encode_text_stream('#{}'.format(f['rev']))
+
+                fileArgs.append(fileArg)
 
             p4CmdList(["-x", "-", "print"],
                       stdin=fileArgs,
                       cb=streamP4FilesCbSelf)
 
             # do the last chunk
-            if self.stream_file.has_key('depotFile'):
+            if 'depotFile' in self.stream_file:
                 self.streamOneP4File(self.stream_file, self.stream_contents)
 
     def make_email(self, userid):
@@ -2162,14 +3163,17 @@ class P4Sync(Command, P4UserMap):
         else:
             return "%s <a@b>" % userid
 
-    # Stream a p4 tag
     def streamTag(self, gitStream, labelName, labelDetails, commit, epoch):
+        """ Stream a p4 tag.
+        commit is either a git commit, or a fast-import mark, ":<p4commit>"
+        """
+
         if verbose:
-            print "writing tag %s for commit %s" % (labelName, commit)
+            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'):
+        if 'Owner' in labelDetails:
             owner = labelDetails["Owner"]
         else:
             owner = None
@@ -2184,8 +3188,8 @@ class P4Sync(Command, P4UserMap):
 
         gitStream.write("tagger %s\n" % tagger)
 
-        print "labelDetails=",labelDetails
-        if labelDetails.has_key('Description'):
+        print("labelDetails=",labelDetails)
+        if 'Description' in labelDetails:
             description = labelDetails['Description']
         else:
             description = 'Label from git p4'
@@ -2194,24 +3198,86 @@ class P4Sync(Command, P4UserMap):
         gitStream.write(description)
         gitStream.write("\n")
 
-    def commit(self, details, files, branch, parent = ""):
+    def inClientSpec(self, path):
+        if not self.clientSpecDirs:
+            return True
+        inClientSpec = self.clientSpecDirs.map_in_client(path)
+        if not inClientSpec and self.verbose:
+            print('Ignoring file outside of client spec: {0}'.format(path))
+        return inClientSpec
+
+    def hasBranchPrefix(self, path):
+        if not self.branchPrefixes:
+            return True
+        hasPrefix = [p for p in self.branchPrefixes
+                        if p4PathStartsWith(path, p)]
+        if not hasPrefix and self.verbose:
+            print('Ignoring file outside of prefix: {0}'.format(path))
+        return hasPrefix
+
+    def findShadowedFiles(self, files, change):
+        # Perforce allows you commit files and directories with the same name,
+        # so you could have files //depot/foo and //depot/foo/bar both checked
+        # in.  A p4 sync of a repository in this state fails.  Deleting one of
+        # the files recovers the repository.
+        #
+        # Git will not allow the broken state to exist and only the most recent
+        # of the conflicting names is left in the repository.  When one of the
+        # conflicting files is deleted we need to re-add the other one to make
+        # sure the git repository recovers in the same way as perforce.
+        deleted = [f for f in files if f['action'] in self.delete_actions]
+        to_check = set()
+        for f in deleted:
+            path = decode_path(f['path'])
+            to_check.add(path + '/...')
+            while True:
+                path = path.rsplit("/", 1)[0]
+                if path == "/" or path in to_check:
+                    break
+                to_check.add(path)
+        to_check = ['%s@%s' % (wildcard_encode(p), change) for p in to_check
+            if self.hasBranchPrefix(p)]
+        if to_check:
+            stat_result = p4CmdList(["-x", "-", "fstat", "-T",
+                "depotFile,headAction,headRev,headType"], stdin=to_check)
+            for record in stat_result:
+                if record['code'] != 'stat':
+                    continue
+                if record['headAction'] in self.delete_actions:
+                    continue
+                files.append({
+                    'action': 'add',
+                    'path': record['depotFile'],
+                    'rev': record['headRev'],
+                    'type': record['headType']})
+
+    def commit(self, details, files, branch, parent = "", allow_empty=False):
         epoch = details["time"]
         author = details["user"]
+        jobs = self.extractJobsFromCommit(details)
 
         if self.verbose:
-            print "commit into %s" % branch
+            print('commit into {0}'.format(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'])
+        files = [f for f in files
+            if self.hasBranchPrefix(decode_path(f['path']))]
+        self.findShadowedFiles(files, details['change'])
+
+        if self.clientSpecDirs:
+            self.clientSpecDirs.update_client_spec_path_cache(files)
+
+        files = [f for f in files if self.inClientSpec(decode_path(f['path']))]
+
+        if gitConfigBool('git-p4.keepEmptyCommits'):
+            allow_empty = True
+
+        if not files and not allow_empty:
+            print('Ignoring revision {0} as it would produce an empty commit.'
+                .format(details['change']))
+            return
 
         self.gitStream.write("commit %s\n" % branch)
-#        gitStream.write("mark :%s\n" % details["change"])
+        self.gitStream.write("mark :%s\n" % details["change"])
         self.committedChanges.add(int(details["change"]))
         committer = ""
         if author not in self.users:
@@ -2222,28 +3288,34 @@ class P4Sync(Command, P4UserMap):
 
         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(jobs) > 0:
+            self.gitStream.write("\nJobs: %s" % (' '.join(jobs)))
+
+        if not self.suppress_meta_comment:
+            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("]\n")
+
+        self.gitStream.write("EOT\n\n")
 
         if len(parent) > 0:
             if self.verbose:
-                print "parent %s" % parent
+                print("parent %s" % parent)
             self.gitStream.write("from %s\n" % parent)
 
-        self.streamP4Files(new_files)
+        self.streamP4Files(files)
         self.gitStream.write("\n")
 
         change = int(details["change"])
 
-        if self.labels.has_key(change):
+        if change in self.labels:
             label = self.labels[change]
             labelDetails = label[0]
             labelRevisions = label[1]
             if self.verbose:
-                print "Change %s is labelled %s" % (change, labelDetails)
+                print("Change %s is labelled %s" % (change, labelDetails))
 
             files = p4CmdList(["files"] + ["%s...@%s" % (p, change)
                                                 for p in self.branchPrefixes])
@@ -2261,12 +3333,12 @@ class P4Sync(Command, P4UserMap):
 
                 else:
                     if not self.silent:
-                        print ("Tag %s does not match with change %s: files do not match."
+                        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."
+                    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.
@@ -2275,14 +3347,14 @@ class P4Sync(Command, P4UserMap):
 
         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`
+            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
+                print("Querying files for label %s" % label)
             for file in p4CmdList(["files"] +
                                       ["%s...@%s" % (p, label)
                                           for p in self.depotPaths]):
@@ -2294,7 +3366,7 @@ class P4Sync(Command, P4UserMap):
             self.labels[newestChange] = [output, revisions]
 
         if self.verbose:
-            print "Label changes: %s" % self.labels.keys()
+            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
@@ -2302,7 +3374,7 @@ class P4Sync(Command, P4UserMap):
     # just ignore.
     def importP4Labels(self, stream, p4Labels):
         if verbose:
-            print "import p4 labels: " + ' '.join(p4Labels)
+            print("import p4 labels: " + ' '.join(p4Labels))
 
         ignoredP4Labels = gitConfigList("git-p4.ignoredP4Labels")
         validLabelRegexp = gitConfig("git-p4.labelImportRegexp")
@@ -2315,7 +3387,7 @@ class P4Sync(Command, P4UserMap):
 
             if not m.match(name):
                 if verbose:
-                    print "label %s does not match regexp %s" % (name,validLabelRegexp)
+                    print("label %s does not match regexp %s" % (name,validLabelRegexp))
                 continue
 
             if name in ignoredP4Labels:
@@ -2327,30 +3399,36 @@ class P4Sync(Command, P4UserMap):
             change = p4Cmd(["changes", "-m", "1"] + ["%s...@%s" % (p, name)
                                 for p in self.depotPaths])
 
-            if change.has_key('change'):
+            if 'change' in 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()
+                if changelist in self.committedChanges:
+                    gitCommit = ":%d" % changelist       # use a fast-import mark
                     commitFound = True
+                else:
+                    gitCommit = read_pipe(["git", "rev-list", "--max-count=1",
+                        "--reverse", ":/\[git-p4:.*change = %d\]" % changelist], ignore_error=True)
+                    if len(gitCommit) == 0:
+                        print("importing label %s: could not find git commit for changelist %d" % (name, changelist))
+                    else:
+                        commitFound = True
+                        gitCommit = gitCommit.strip()
+
+                if commitFound:
                     # 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" % labelDetail['Update']
+                        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)
+                        print("p4 label %s mapped to git commit %s" % (name, gitCommit))
             else:
                 if verbose:
-                    print "Label %s has no changelists - possibly deleted?" % name
+                    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
@@ -2380,7 +3458,7 @@ class P4Sync(Command, P4UserMap):
         for info in p4CmdList(command):
             details = p4Cmd(["branch", "-o", info["branch"]])
             viewIdx = 0
-            while details.has_key("View%s" % viewIdx):
+            while "View%s" % viewIdx in details:
                 paths = details["View%s" % viewIdx].split(" ")
                 viewIdx = viewIdx + 1
                 # require standard //depot/foo/... //depot/bar/... mapping
@@ -2395,8 +3473,8 @@ class P4Sync(Command, P4UserMap):
 
                     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)
+                            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
@@ -2438,13 +3516,6 @@ class P4Sync(Command, P4UserMap):
                 branch = branch[len(self.projectName):]
             self.knownBranches[branch] = branch
 
-    def listExistingP4GitBranches(self):
-        # branches holds mapping from name to commit
-        branches = p4BranchesInGit(self.importIntoRemotes)
-        self.p4BranchesInGit = branches.keys()
-        for branch in branches.keys():
-            self.initialParents[self.refPrefix + branch] = branches[branch]
-
     def updateOptionDict(self, d):
         option_keys = {}
         if self.keepRepoPath:
@@ -2453,7 +3524,7 @@ class P4Sync(Command, P4UserMap):
         d["options"] = ' '.join(sorted(option_keys.keys()))
 
     def readOptions(self, d):
-        self.keepRepoPath = (d.has_key('options')
+        self.keepRepoPath = ('options' in d
                              and ('keepRepoPath' in d['options']))
 
     def gitRefForBranch(self, branch):
@@ -2467,34 +3538,36 @@ class P4Sync(Command, P4UserMap):
 
     def gitCommitByP4Change(self, ref, change):
         if self.verbose:
-            print "looking in ref " + ref + " for change %s using bisect..." % change
+            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)
+                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"
+                    print("argh")
                 return ""
             log = extractLogMessageFromGitCommit(next)
             settings = extractSettingsGitLog(log)
             currentChange = int(settings['change'])
             if self.verbose:
-                print "current change %s" % currentChange
+                print("current change %s" % currentChange)
 
             if currentChange == change:
                 if self.verbose:
-                    print "found %s" % next
+                    print("found %s" % next)
                 return next
 
             if currentChange < change:
                 earliestCommit = "^%s" % next
             else:
-                latestCommit = "%s" % next
+                if next == latestCommit:
+                    die("Infinite loop while looking in ref %s for change %s. Check your branch mappings" % (ref, change))
+                latestCommit = "%s^@" % next
 
         return ""
 
@@ -2506,7 +3579,7 @@ class P4Sync(Command, P4UserMap):
         branchPrefix = self.depotPaths[0] + branch + "/"
         range = "@1,%s" % maxChange
         #print "prefix" + branchPrefix
-        changes = p4ChangesForPaths([branchPrefix], range)
+        changes = p4ChangesForPaths([branchPrefix], range, self.changes_block_size)
         if len(changes) <= 0:
             return False
         firstChange = changes[0]
@@ -2528,22 +3601,23 @@ class P4Sync(Command, P4UserMap):
 
     def searchParent(self, parent, branch, target):
         parentFound = False
-        for blob in read_pipe_lines(["git", "rev-list", "--reverse", "--no-merges", parent]):
+        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)
+                    print("Found parent of %s in commit %s" % (branch, blob))
                 break
         if parentFound:
             return blob
         else:
             return None
 
-    def importChanges(self, changes):
+    def importChanges(self, changes, origin_revision=0):
         cnt = 1
         for change in changes:
-            description = p4Cmd(["describe", str(change)])
+            description = p4_describe(change)
             self.updateOptionDict(description)
 
             if not self.silent:
@@ -2564,7 +3638,7 @@ class P4Sync(Command, P4UserMap):
                         filesForCommit = branches[branch]
 
                         if self.verbose:
-                            print "branch is %s" % branch
+                            print("branch is %s" % branch)
 
                         self.updatedBranches.add(branch)
 
@@ -2585,13 +3659,13 @@ class P4Sync(Command, P4UserMap):
                                         print("\n    Resuming with change %s" % change);
 
                                 if self.verbose:
-                                    print "parent determined through known branches: %s" % parent
+                                    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)
+                            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]
@@ -2599,9 +3673,9 @@ class P4Sync(Command, P4UserMap):
 
                         blob = None
                         if len(parent) > 0:
-                            tempBranch = os.path.join(self.tempBranchLocation, "%d" % (change))
+                            tempBranch = "%s/%d" % (self.tempBranchLocation, change)
                             if self.verbose:
-                                print "Creating temporary branch: " + tempBranch
+                                print("Creating temporary branch: " + tempBranch)
                             self.commit(description, filesForCommit, tempBranch)
                             self.tempBranches.append(tempBranch)
                             self.checkpoint()
@@ -2610,19 +3684,28 @@ class P4Sync(Command, P4UserMap):
                             self.commit(description, filesForCommit, branch, blob)
                         else:
                             if self.verbose:
-                                print "Parent of %s not found. Committing into head of %s" % (branch, parent)
+                                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()
+                print(self.gitError.read())
                 sys.exit(1)
 
+    def sync_origin_only(self):
+        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")
+
     def importHeadRevision(self, revision):
-        print "Doing initial import of %s from revision %s into %s" % (' '.join(self.depotPaths), revision, self.branch)
+        print("Doing initial import of %s from revision %s into %s" % (' '.join(self.depotPaths), revision, self.branch))
 
         details = {}
         details["user"] = "git perforce import user"
@@ -2667,61 +3750,134 @@ class P4Sync(Command, P4UserMap):
 
         # Use time from top-most change so that all git p4 clones of
         # the same p4 repo have the same commit SHA1s.
-        res = p4CmdList("describe -s %d" % newestRevision)
-        newestTime = None
-        for r in res:
-            if r.has_key('time'):
-                newestTime = int(r['time'])
-        if newestTime is None:
-            die("\"describe -s\" on newest change %d did not give a time")
-        details["time"] = newestTime
+        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()
+        except IOError as err:
+            print("IO error with git fast-import. Is your git version recent enough?")
+            print("IO error details: {}".format(err))
+            print(self.gitError.read())
 
 
-    def run(self, args):
-        self.depotPaths = []
-        self.changeRange = ""
-        self.initialParent = ""
-        self.previousDepotPaths = []
+    def importRevisions(self, args, branch_arg_given):
+        changes = []
 
-        # map from branch depot path to parent branch
-        self.knownBranches = {}
-        self.initialParents = {}
-        self.hasOrigin = originP4BranchesExist()
-        if not self.syncWithOrigin:
-            self.hasOrigin = False
+        if len(self.changesFile) > 0:
+            with open(self.changesFile) as f:
+                output = f.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:
+                    raise P4CommandException("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:
+                            raise P4CommandException("Error: branch %s does not exist." % self.branch)
+                        else:
+                            raise P4CommandException("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, self.changes_block_size)
+
+            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")
+
+    def openStreams(self):
+        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 bytes is not str:
+            # Wrap gitStream.write() so that it can be called using `str` arguments
+            def make_encoded_write(write):
+                def encoded_write(s):
+                    return write(s.encode() if isinstance(s, str) else s)
+                return encoded_write
+
+            self.gitStream.write = make_encoded_write(self.gitStream.write)
+
+    def closeStreams(self):
+        if self.gitStream is None:
+            return
+        self.gitStream.close()
+        if self.importProcess.wait() != 0:
+            die("fast-import failed: %s" % self.gitError.read())
+        self.gitOutput.close()
+        self.gitError.close()
+        self.gitStream = None
 
+    def run(self, args):
         if self.importIntoRemotes:
             self.refPrefix = "refs/remotes/p4/"
         else:
             self.refPrefix = "refs/heads/p4/"
 
-        if self.syncWithOrigin and self.hasOrigin:
-            if not self.silent:
-                print "Syncing with origin first by calling git fetch origin"
-            system("git fetch origin")
+        self.sync_origin_only()
 
+        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");
-            # create it /after/ importing, when master exists
-            if not gitBranchExists(self.refPrefix + "HEAD") and self.importIntoRemotes and gitBranchExists(self.branch):
-                system("git symbolic-ref %sHEAD %s" % (self.refPrefix, 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 gitConfig("git-p4.useclientspec", "--bool") == "true":
+            if gitConfigBool("git-p4.useclientspec"):
                 self.useClientSpec = True
         if self.useClientSpec:
             self.clientSpecDirs = getClientSpec()
@@ -2731,15 +3887,28 @@ class P4Sync(Command, P4UserMap):
         if args == []:
             if self.hasOrigin:
                 createOrUpdateBranchesFromOrigin(self.refPrefix, self.silent)
-            self.listExistingP4GitBranches()
+
+            # 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"
+                    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
+                print("branches: %s" % self.p4BranchesInGit)
 
             p4Change = 0
             for branch in self.p4BranchesInGit:
@@ -2748,8 +3917,8 @@ class P4Sync(Command, P4UserMap):
                 settings = extractSettingsGitLog(logMsg)
 
                 self.readOptions(settings)
-                if (settings.has_key('depot-paths')
-                    and settings.has_key ('change')):
+                if ('depot-paths' in settings
+                    and 'change' in settings):
                     change = int(settings['change']) + 1
                     p4Change = max(p4Change, change)
 
@@ -2762,7 +3931,7 @@ class P4Sync(Command, P4UserMap):
                             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]:
+                                if cur_list[i] != prev_list[i]:
                                     i = i - 1
                                     break
 
@@ -2773,20 +3942,28 @@ class P4Sync(Command, P4UserMap):
             if p4Change > 0:
                 self.depotPaths = sorted(self.previousDepotPaths)
                 self.changeRange = "@%s,#head" % p4Change
-                if not self.detectBranches:
-                    self.initialParent = parseRevision(self.branch)
                 if not self.silent and not self.detectBranches:
-                    print "Performing incremental import into %s git branch" % self.branch
+                    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/"):
-            self.branch = "refs/heads/" + self.branch
+            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)
+                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. "
+                print("previous import used depot path %s and now %s was specified. "
                        "This doesn't work!" % (' '.join (self.depotPaths),
                                                ' '.join (args)))
                 sys.exit(1)
@@ -2853,8 +4030,8 @@ class P4Sync(Command, P4UserMap):
             else:
                 self.getBranchMapping()
             if self.verbose:
-                print "p4-git branches: %s" % self.p4BranchesInGit
-                print "initial parents: %s" % self.initialParents
+                print("p4-git branches: %s" % self.p4BranchesInGit)
+                print("initial parents: %s" % self.initialParents)
             for b in self.p4BranchesInGit:
                 if b != "master":
 
@@ -2862,77 +4039,36 @@ class P4Sync(Command, P4UserMap):
                     b = b[len(self.projectName):]
                 self.createdBranches.add(b)
 
-        self.tz = "%+03d%02d" % (- time.timezone / 3600, ((- time.timezone % 3600) / 60))
-
-        importProcess = subprocess.Popen(["git", "fast-import"],
-                                         stdin=subprocess.PIPE, stdout=subprocess.PIPE,
-                                         stderr=subprocess.PIPE);
-        self.gitOutput = importProcess.stdout
-        self.gitStream = importProcess.stdin
-        self.gitError = importProcess.stderr
-
-        if revision:
-            self.importHeadRevision(revision)
-        else:
-            changes = []
+        p4_check_access()
 
-            if len(self.changesFile) > 0:
-                output = open(self.changesFile).readlines()
-                changeSet = set()
-                for line in output:
-                    changeSet.add(int(line))
+        self.openStreams()
 
-                for change in changeSet:
-                    changes.append(change)
+        err = None
 
-                changes.sort()
+        try:
+            if revision:
+                self.importHeadRevision(revision)
             else:
-                # catch "git p4 sync" with no new branches, in a repo that
-                # does not have any existing p4 branches
-                if len(args) == 0 and not self.p4BranchesInGit:
-                    die("No remote p4 branches.  Perhaps you never did \"git p4 clone\" in here.");
-                if self.verbose:
-                    print "Getting p4 changes for %s...%s" % (', '.join(self.depotPaths),
-                                                              self.changeRange)
-                changes = p4ChangesForPaths(self.depotPaths, self.changeRange)
+                self.importRevisions(args, branch_arg_given)
 
-                if len(self.maxChanges) > 0:
-                    changes = changes[:min(int(self.maxChanges), len(changes))]
+            if gitConfigBool("git-p4.importLabels"):
+                self.importLabels = True
 
-            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
+            if self.importLabels:
+                p4Labels = getP4Labels(self.depotPaths)
+                gitTags = getGitTags()
 
-                self.updatedBranches = set()
+                missingP4Labels = p4Labels - gitTags
+                self.importP4Labels(self.gitStream, missingP4Labels)
 
-                self.importChanges(changes)
+        except P4CommandException as e:
+            err = e
 
-                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 gitConfig("git-p4.importLabels", "--bool") == "true":
-            self.importLabels = True
-
-        if self.importLabels:
-            p4Labels = getP4Labels(self.depotPaths)
-            gitTags = getGitTags()
+        finally:
+            self.closeStreams()
 
-            missingP4Labels = p4Labels - gitTags
-            self.importP4Labels(self.gitStream, missingP4Labels)
-
-        self.gitStream.close()
-        if importProcess.wait() != 0:
-            die("fast-import failed: %s" % self.gitError.read())
-        self.gitOutput.close()
-        self.gitError.close()
+        if err:
+            die(str(err))
 
         # Cleanup temporary branches created during import
         if self.tempBranches != []:
@@ -2940,6 +4076,13 @@ class P4Sync(Command, P4UserMap):
                 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):
@@ -2961,9 +4104,9 @@ class P4Rebase(Command):
 
     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.");
+            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 uncommited changes. Please commit them before rebasing or stash them away with git stash.");
+            die("You have uncommitted changes. Please commit them before rebasing or stash them away with git stash.");
 
         [upstream, settings] = findUpstreamBranchPoint()
         if len(upstream) == 0:
@@ -2972,10 +4115,10 @@ class P4Rebase(Command):
         # 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
+        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)
+        system("git diff-tree --stat --summary -M %s HEAD --" % oldHead)
         return True
 
 class P4Clone(P4Sync):
@@ -2987,9 +4130,6 @@ class P4Clone(P4Sync):
             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),
         ]
@@ -2997,12 +4137,6 @@ class P4Clone(P4Sync):
         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]
@@ -3026,15 +4160,15 @@ class P4Clone(P4Sync):
             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)
+        print("Importing from %s into %s" % (', '.join(depotPaths), self.cloneDestination))
 
         if not os.path.exists(self.cloneDestination):
             os.makedirs(self.cloneDestination)
@@ -3043,21 +4177,21 @@ class P4Clone(P4Sync):
         init_cmd = [ "git", "init" ]
         if self.cloneBare:
             init_cmd.append("--bare")
-        subprocess.check_call(init_cmd)
+        retcode = subprocess.call(init_cmd)
+        if retcode:
+            raise CalledProcessError(retcode, init_cmd)
 
         if not P4Sync.run(self, depotPaths):
             return False
-        if self.branch != "master":
-            if self.importIntoRemotes:
-                masterbranch = "refs/remotes/p4/master"
-            else:
-                masterbranch = "refs/heads/p4/master"
-            if gitBranchExists(masterbranch):
-                system("git branch master %s" % masterbranch)
-                if not self.cloneBare:
-                    system("git checkout -f")
-            else:
-                print "Could not detect main branch. No checkout/master branch created."
+
+        # create a master branch and check out a work tree
+        if gitBranchExists(self.branch):
+            system([ "git", "branch", currentGitBranch(), 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:
@@ -3065,6 +4199,121 @@ class P4Clone(P4Sync):
 
         return True
 
+class P4Unshelve(Command):
+    def __init__(self):
+        Command.__init__(self)
+        self.options = []
+        self.origin = "HEAD"
+        self.description = "Unshelve a P4 changelist into a git commit"
+        self.usage = "usage: %prog [options] changelist"
+        self.options += [
+                optparse.make_option("--origin", dest="origin",
+                    help="Use this base revision instead of the default (%s)" % self.origin),
+        ]
+        self.verbose = False
+        self.noCommit = False
+        self.destbranch = "refs/remotes/p4-unshelved"
+
+    def renameBranch(self, branch_name):
+        """ Rename the existing branch to branch_name.N
+        """
+
+        found = True
+        for i in range(0,1000):
+            backup_branch_name = "{0}.{1}".format(branch_name, i)
+            if not gitBranchExists(backup_branch_name):
+                gitUpdateRef(backup_branch_name, branch_name) # copy ref to backup
+                gitDeleteRef(branch_name)
+                found = True
+                print("renamed old unshelve branch to {0}".format(backup_branch_name))
+                break
+
+        if not found:
+            sys.exit("gave up trying to rename existing branch {0}".format(sync.branch))
+
+    def findLastP4Revision(self, starting_point):
+        """ Look back from starting_point for the first commit created by git-p4
+            to find the P4 commit we are based on, and the depot-paths.
+        """
+
+        for parent in (range(65535)):
+            log = extractLogMessageFromGitCommit("{0}~{1}".format(starting_point, parent))
+            settings = extractSettingsGitLog(log)
+            if 'change' in settings:
+                return settings
+
+        sys.exit("could not find git-p4 commits in {0}".format(self.origin))
+
+    def createShelveParent(self, change, branch_name, sync, origin):
+        """ Create a commit matching the parent of the shelved changelist 'change'
+        """
+        parent_description = p4_describe(change, shelved=True)
+        parent_description['desc'] = 'parent for shelved changelist {}\n'.format(change)
+        files = sync.extractFilesFromCommit(parent_description, shelved=False, shelved_cl=change)
+
+        parent_files = []
+        for f in files:
+            # if it was added in the shelved changelist, it won't exist in the parent
+            if f['action'] in self.add_actions:
+                continue
+
+            # if it was deleted in the shelved changelist it must not be deleted
+            # in the parent - we might even need to create it if the origin branch
+            # does not have it
+            if f['action'] in self.delete_actions:
+                f['action'] = 'add'
+
+            parent_files.append(f)
+
+        sync.commit(parent_description, parent_files, branch_name,
+                parent=origin, allow_empty=True)
+        print("created parent commit for {0} based on {1} in {2}".format(
+            change, self.origin, branch_name))
+
+    def run(self, args):
+        if len(args) != 1:
+            return False
+
+        if not gitBranchExists(self.origin):
+            sys.exit("origin branch {0} does not exist".format(self.origin))
+
+        sync = P4Sync()
+        changes = args
+
+        # only one change at a time
+        change = changes[0]
+
+        # if the target branch already exists, rename it
+        branch_name = "{0}/{1}".format(self.destbranch, change)
+        if gitBranchExists(branch_name):
+            self.renameBranch(branch_name)
+        sync.branch = branch_name
+
+        sync.verbose = self.verbose
+        sync.suppress_meta_comment = True
+
+        settings = self.findLastP4Revision(self.origin)
+        sync.depotPaths = settings['depot-paths']
+        sync.branchPrefixes = sync.depotPaths
+
+        sync.openStreams()
+        sync.loadUserMapFromCache()
+        sync.silent = True
+
+        # create a commit for the parent of the shelved changelist
+        self.createShelveParent(change, branch_name, sync, self.origin)
+
+        # create the commit for the shelved changelist itself
+        description = p4_describe(change, True)
+        files = sync.extractFilesFromCommit(description, True, change)
+
+        sync.commit(description, files, branch_name, "")
+        sync.closeStreams()
+
+        print("unshelved changelist {0} into {1}".format(change, branch_name))
+
+        return True
+
 class P4Branches(Command):
     def __init__(self):
         Command.__init__(self)
@@ -3090,7 +4339,7 @@ class P4Branches(Command):
             log = extractLogMessageFromGitCommit("refs/remotes/%s" % branch)
             settings = extractSettingsGitLog(log)
 
-            print "%s <= %s (%s)" % (branch, ",".join(settings["depot-paths"]), settings["change"])
+            print("%s <= %s (%s)" % (branch, ",".join(settings["depot-paths"]), settings["change"]))
         return True
 
 class HelpFormatter(optparse.IndentedHelpFormatter):
@@ -3104,12 +4353,12 @@ class HelpFormatter(optparse.IndentedHelpFormatter):
             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 ""
+    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,
@@ -3119,23 +4368,22 @@ commands = {
     "rebase" : P4Rebase,
     "clone" : P4Clone,
     "rollback" : P4RollBack,
-    "branches" : P4Branches
+    "branches" : P4Branches,
+    "unshelve" : P4Unshelve,
 }
 
-
 def main():
     if len(sys.argv[1:]) == 0:
         printUsage(commands.keys())
         sys.exit(2)
 
-    cmd = ""
     cmdName = sys.argv[1]
     try:
         klass = commands[cmdName]
         cmd = klass()
     except KeyError:
-        print "unknown command %s" % cmdName
-        print ""
+        print("unknown command %s" % cmdName)
+        print("")
         printUsage(commands.keys())
         sys.exit(2)
 
@@ -3153,13 +4401,19 @@ def main():
                                    description = cmd.description,
                                    formatter = HelpFormatter())
 
-    (cmd, args) = parser.parse_args(sys.argv[2:], cmd);
+    try:
+        (cmd, args) = parser.parse_args(sys.argv[2:], cmd);
+    except:
+        parser.print_help()
+        raise
+
     global verbose
     verbose = cmd.verbose
     if cmd.needsGit:
         if cmd.gitdir == None:
             cmd.gitdir = os.path.abspath(".git")
             if not isValidGitDir(cmd.gitdir):
+                # "rev-parse --git-dir" without arguments will try $PWD/.git
                 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()
@@ -3172,6 +4426,7 @@ def main():
             else:
                 die("fatal: cannot locate git repository at %s" % cmd.gitdir)
 
+        # so git commands invoked from the P4 workspace will succeed
         os.environ["GIT_DIR"] = cmd.gitdir
 
     if not cmd.run(args):