make update-server-info more robust
[gitweb.git] / git-p4.py
index 0682e61e90dca3f88f399c20aa19c5336274bc95..ff132b2117c5ed7529d6b1237a9f26069cb4ef8a 100755 (executable)
--- a/git-p4.py
+++ b/git-p4.py
@@ -7,10 +7,21 @@
 #            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
+import sys
+if sys.hexversion < 0x02040000:
+    # The limiter is the subprocess module
+    sys.stderr.write("git-p4: requires Python 2.4 or later.\n")
+    sys.exit(1)
+import os
+import optparse
+import marshal
+import subprocess
+import tempfile
+import time
+import platform
+import re
+import shutil
+import stat
 
 try:
     from subprocess import CalledProcessError
@@ -68,12 +79,27 @@ def p4_build_cmd(cmd):
         real_cmd += cmd
     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 chdir(path, is_client_path=False):
+    """Do chdir to the given path, and set the PWD environment
+       variable for use by P4.  It does not look at getcwd() output.
+       Since we're not using the shell, it is necessary to set the
+       PWD environment variable explicitly.
+
+       Normally, expand the path to force it to be absolute.  This
+       addresses the use of relative path names inside P4 settings,
+       e.g. P4CONFIG=.p4config.  P4 does not simply open the filename
+       as given; it looks for .p4config using PWD.
+
+       If is_client_path, the path was handed to us directly by p4,
+       and may be a symbolic link.  Do not call os.getcwd() in this
+       case, because it will cause p4 to think that PWD is not inside
+       the client path.
+       """
+
+    os.chdir(path)
+    if not is_client_path:
+        path = os.getcwd()
+    os.environ['PWD'] = path
 
 def die(msg):
     if verbose:
@@ -179,6 +205,22 @@ def p4_system(cmd):
     if retcode:
         raise CalledProcessError(retcode, real_cmd)
 
+_p4_version_string = None
+def p4_version_string():
+    """Read the version string, showing just the last line, which
+       hopefully is the interesting version bit.
+
+       $ p4 -V
+       Perforce - The Fast Software Configuration Management System.
+       Copyright 1995-2011 Perforce Software.  All rights reserved.
+       Rev. P4/NTX86/2011.1/393975 (2011/12/16).
+    """
+    global _p4_version_string
+    if not _p4_version_string:
+        a = p4_read_pipe_lines(["-V"])
+        _p4_version_string = a[-1].rstrip()
+    return _p4_version_string
+
 def p4_integrate(src, dest):
     p4_system(["integrate", "-Dt", wildcard_encode(src), wildcard_encode(dest)])
 
@@ -268,8 +310,8 @@ 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']
 
 #
@@ -552,43 +594,75 @@ def gitBranchExists(branch):
     return proc.wait() == 0;
 
 _gitConfig = {}
-def gitConfig(key, args = None): # set args to "--bool", for instance
+
+def gitConfig(key):
     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()
+        cmd = [ "git", "config", key ]
+        s = read_pipe(cmd, ignore_error=True)
+        _gitConfig[key] = s.strip()
+    return _gitConfig[key]
+
+def gitConfigBool(key):
+    """Return a bool, using git config --bool.  It is True only if the
+       variable is set to true, and False if set to false or not present
+       in the config."""
+
+    if not _gitConfig.has_key(key):
+        cmd = [ "git", "config", "--bool", key ]
+        s = read_pipe(cmd, ignore_error=True)
+        v = s.strip()
+        _gitConfig[key] = v == "true"
     return _gitConfig[key]
 
 def gitConfigList(key):
     if not _gitConfig.has_key(key):
-        _gitConfig[key] = read_pipe("git config --get-all %s" % key, ignore_error=True).strip().split(os.linesep)
+        s = read_pipe(["git", "config", "--get-all", key], ignore_error=True)
+        _gitConfig[key] = s.strip().split(os.linesep)
     return _gitConfig[key]
 
-def p4BranchesInGit(branchesAreInRemotes = True):
+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()
+    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
@@ -690,8 +764,7 @@ 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)
 
@@ -707,11 +780,14 @@ 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)):
@@ -921,19 +997,21 @@ def __init__(self):
                 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"),
         ]
         self.description = "Submit changes from git to the perforce depot."
         self.usage += " [name of git branch to submit into perforce depot]"
         self.origin = ""
         self.detectRenames = False
-        self.preserveUser = gitConfig("git-p4.preserveUser").lower() == "true"
+        self.preserveUser = gitConfigBool("git-p4.preserveUser")
         self.dry_run = False
         self.prepare_p4_only = False
         self.conflict_behavior = None
         self.isWindows = (platform.system() == "Windows")
         self.exportLabels = False
         self.p4HasMoveCommand = p4_has_move_command()
+        self.branch = None
 
     def check(self):
         if len(p4CmdList("opened ...")) > 0:
@@ -1021,7 +1099,8 @@ def patchRCSKeywords(self, file, pattern):
     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):
             return (None,gitEmail)
@@ -1034,7 +1113,7 @@ def checkValidP4Users(self,commits):
             (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":
+                if gitConfigBool("git-p4.allowMissingP4Users"):
                     print "%s" % msg
                 else:
                     die("Error: %s\nSet git-p4.allowMissingP4Users to true to allow this." % msg)
@@ -1129,7 +1208,7 @@ def edit_template(self, template_file):
            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
@@ -1141,11 +1220,11 @@ def edit_template(self, template_file):
             editor = os.environ.get("P4EDITOR")
         else:
             editor = read_pipe("git var GIT_EDITOR").strip()
-        system(editor + " " + template_file)
+        system([editor, template_file])
 
         # If the file was not saved, prompt to see if this patch should
         # be skipped.  But skip this verification step if configured so.
-        if gitConfig("git-p4.skipSubmitEditCheck") == "true":
+        if gitConfigBool("git-p4.skipSubmitEditCheck"):
             return True
 
         # modification time updated means user saved the file
@@ -1159,6 +1238,28 @@ def edit_template(self, template_file):
             if response == 'n':
                 return False
 
+    def get_diff_description(self, editedFiles, filesToAdd):
+        # 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()
+
+        return (diff + newdiff).replace('\r\n', '\n')
+
     def applyCommit(self, id):
         """Apply one commit, return True if it succeeded."""
 
@@ -1203,6 +1304,9 @@ def applyCommit(self, id):
                     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":
@@ -1221,13 +1325,15 @@ def applyCommit(self, id):
                         p4_edit(dest)   # with move: already open, writable
                     filesToChangeExecBit[dest] = diff['dst_mode']
                 if not self.p4HasMoveCommand:
+                    if self.isWindows:
+                        os.chmod(dest, stat.S_IWRITE)
                     os.unlink(dest)
                     filesToDelete.add(src)
                 editedFiles.add(dest)
             else:
                 die("unknown modifier %s for %s" % (modifier, path))
 
-        diffcmd = "git format-patch -k --stdout \"%s^\"..\"%s\"" % (id, id)
+        diffcmd = "git diff-tree --full-index -p \"%s\"" % (id)
         patchcmd = diffcmd + " | git apply "
         tryPatchCmd = patchcmd + "--check -"
         applyPatchCmd = patchcmd + "--check --apply -"
@@ -1240,7 +1346,7 @@ def applyCommit(self, id):
 
             # 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 = {}
@@ -1261,6 +1367,10 @@ def applyCommit(self, id):
                 for file in kwfiles:
                     if verbose:
                         print "zapping %s with %s" % (line,pattern)
+                    # File is being deleted, so not open in p4.  Must
+                    # disable the read-only bit on windows.
+                    if self.isWindows and file not in editedFiles:
+                        os.chmod(file, stat.S_IWRITE)
                     self.patchRCSKeywords(file, kwfiles[file])
                     fixed_rcs_keywords = True
 
@@ -1310,34 +1420,15 @@ def applyCommit(self, id):
             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)
 
-        # 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(submitTemplate)
         tmpFile.close()
 
         if self.prepare_p4_only:
@@ -1384,9 +1475,9 @@ def applyCommit(self, id):
             tmpFile = open(fileName, "rb")
             message = tmpFile.read()
             tmpFile.close()
-            submitTemplate = message[:message.index(separatorLine)]
             if self.isWindows:
-                submitTemplate = submitTemplate.replace("\r\n", "\n")
+                message = message.replace("\r\n", "\n")
+            submitTemplate = message[:message.index(separatorLine)]
             p4_write_pipe(['submit', '-i'], submitTemplate)
 
             if self.preserveUser:
@@ -1470,8 +1561,8 @@ def exportGitTags(self, gitTags):
             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
@@ -1483,7 +1574,7 @@ def exportGitTags(self, gitTags):
 
                 # 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
@@ -1531,7 +1622,7 @@ def run(self, args):
             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()
@@ -1554,7 +1645,7 @@ def run(self, args):
             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
         else:
@@ -1567,11 +1658,11 @@ def run(self, args):
         self.check()
 
         commits = []
-        for line in read_pipe_lines("git rev-list --no-merges %s..%s" % (self.origin, self.master)):
+        for line in read_pipe_lines(["git", "rev-list", "--no-merges", "%s..%s" % (self.origin, self.master)]):
             commits.append(line.strip())
         commits.reverse()
 
-        if self.preserveUser or (gitConfig("git-p4.skipUserNameCheck") == "true"):
+        if self.preserveUser or gitConfigBool("git-p4.skipUserNameCheck"):
             self.checkAuthorship = False
         else:
             self.checkAuthorship = True
@@ -1607,7 +1698,7 @@ def run(self, args):
         else:
             self.diffOpts += " -C%s" % detectCopies
 
-        if gitConfig("git-p4.detectCopiesHarder", "--bool") == "true":
+        if gitConfigBool("git-p4.detectCopiesHarder"):
             self.diffOpts += " --find-copies-harder"
 
         #
@@ -1670,6 +1761,8 @@ def run(self, args):
             print "All commits applied!"
 
             sync = P4Sync()
+            if self.branch:
+                sync.branch = self.branch
             sync.run([])
 
             rebase = P4Rebase()
@@ -1689,7 +1782,7 @@ def run(self, args):
                                            "--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:
@@ -1699,7 +1792,7 @@ def run(self, args):
             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)
 
@@ -1709,117 +1802,16 @@ 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.
@@ -1847,76 +1839,62 @@ def append(self, view_line):
             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 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."""
+    def convert_client_path(self, clientFile):
+        # chop off //client/ part to make it relative
+        if not clientFile.startswith(self.client_prefix):
+            die("No prefix '%s' on clientFile '%s'" %
+                (self.client_prefix, clientFile))
+        return clientFile[len(self.client_prefix):]
 
-        paths_filled = []
-        client_path = ""
+    def update_client_spec_path_cache(self, files):
+        """ Caching file paths by "p4 where" batch query """
 
-        # look at later entries first
-        for m in self.mappings[::-1]:
+        # List depot file paths exclude that already cached
+        fileArgs = [f['path'] for f in files if f['path'] not in self.client_spec_path_cache]
 
-            # see where will this path end up in the client
-            p = m.map_depot_to_client(depot_path)
+        if len(fileArgs) == 0:
+            return  # All files in cache
 
-            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)
+        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
+            self.client_spec_path_cache[res['depotFile']] = self.convert_client_path(res["clientFile"])
 
-            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
+        # not found files or unmap files set to ""
+        for depotFile in fileArgs:
+            if depotFile not in self.client_spec_path_cache:
+                self.client_spec_path_cache[depotFile] = ""
 
-                # a match, even if rejected, always stops the search
-                break
+    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."""
 
-        return client_path
+        if depot_path in self.client_spec_path_cache:
+            return self.client_spec_path_cache[depot_path]
+
+        die( "Error: %s is not found in client spec path" % depot_path )
+        return ""
 
 class P4Sync(Command, P4UserMap):
     delete_actions = ( "delete", "move/delete", "purge" )
@@ -1959,7 +1937,6 @@ def __init__(self):
         self.syncWithOrigin = True
         self.importIntoRemotes = True
         self.maxChanges = ""
-        self.isWindows = (platform.system() == "Windows")
         self.keepRepoPath = False
         self.depotPaths = None
         self.p4BranchesInGit = []
@@ -2044,6 +2021,10 @@ def splitFilesIntoBranches(self, commit):
         """Look at each depotFile in the commit to figure out to what
            branch it belongs."""
 
+        if self.clientSpecDirs:
+            files = self.extractFilesFromCommit(commit)
+            self.clientSpecDirs.update_client_spec_path_cache(files)
+
         branches = {}
         fnum = 0
         while commit.has_key("depotFile%s" % fnum):
@@ -2094,9 +2075,20 @@ def streamOneP4File(self, file, contents):
             git_mode = "100755"
         if type_base == "symlink":
             git_mode = "120000"
-            # p4 print on a symlink contains "target\n"; remove the newline
+            # p4 print on a symlink sometimes contains "target\n";
+            # if it does, remove the newline
             data = ''.join(contents)
-            contents = [data[:-1]]
+            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['depotFile']
+                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
@@ -2104,7 +2096,14 @@ def streamOneP4File(self, file, contents):
             # operations.  utf16 is converted to ascii or utf8, perhaps.
             # But ascii text saved as -t utf16 is completely mangled.
             # Invoke print -o to get the real contents.
+            #
+            # On windows, the newlines will always be mangled by print, so put
+            # them back too.  This is not needed to the cygwin windows version,
+            # just the native "NT" type.
+            #
             text = p4_read_pipe(['print', '-q', '-o', '-', file['depotFile']])
+            if p4_version_string().find("/NT") >= 0:
+                text = text.replace("\r\n", "\n")
             contents = [ text ]
 
         if type_base == "apple":
@@ -2120,15 +2119,6 @@ def streamOneP4File(self, file, contents):
             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)
@@ -2295,6 +2285,9 @@ def commit(self, details, files, branch, parent = ""):
             else:
                 sys.stderr.write("Ignoring file outside of prefix: %s\n" % f['path'])
 
+        if self.clientSpecDirs:
+            self.clientSpecDirs.update_client_spec_path_cache(files)
+
         self.gitStream.write("commit %s\n" % branch)
 #        gitStream.write("mark :%s\n" % details["change"])
         self.committedChanges.add(int(details["change"]))
@@ -2523,13 +2516,6 @@ def getBranchMappingFromGitBranches(self):
                 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:
@@ -2613,7 +2599,8 @@ def importNewBranch(self, branch, maxChange):
 
     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
@@ -2684,7 +2671,7 @@ def importChanges(self, changes):
 
                         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
                             self.commit(description, filesForCommit, tempBranch)
@@ -2701,6 +2688,7 @@ def importChanges(self, changes):
                     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()
@@ -2766,41 +2754,38 @@ def importHeadRevision(self, revision):
     def run(self, args):
         self.depotPaths = []
         self.changeRange = ""
-        self.initialParent = ""
         self.previousDepotPaths = []
+        self.hasOrigin = False
 
         # map from branch depot path to parent branch
         self.knownBranches = {}
         self.initialParents = {}
-        self.hasOrigin = originP4BranchesExist()
-        if not self.syncWithOrigin:
-            self.hasOrigin = False
 
         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")
+        if self.syncWithOrigin:
+            self.hasOrigin = originP4BranchesExist()
+            if self.hasOrigin:
+                if not self.silent:
+                    print 'Syncing with origin first, using "git fetch origin"'
+                system("git fetch origin")
 
+        branch_arg_given = bool(self.branch)
         if len(self.branch) == 0:
             self.branch = self.refPrefix + "master"
             if gitBranchExists("refs/heads/p4") and self.importIntoRemotes:
                 system("git update-ref %s refs/heads/p4" % self.branch)
-                system("git branch -D p4");
-            # 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()
@@ -2810,12 +2795,25 @@ def run(self, args):
         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"
                 self.detectBranches = True
+                for branch in branches.keys():
+                    self.initialParents[self.refPrefix + branch] = \
+                        branches[branch]
 
             if self.verbose:
                 print "branches: %s" % self.p4BranchesInGit
@@ -2852,13 +2850,21 @@ def run(self, args):
             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
 
+        # 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:
@@ -2969,8 +2975,21 @@ def run(self, args):
             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 len(args) == 0:
+                    if not self.p4BranchesInGit:
+                        die("No remote p4 branches.  Perhaps you never did \"git p4 clone\" in here.")
+
+                    # The default branch is master, unless --branch is used to
+                    # specify something else.  Make sure it exists, or complain
+                    # nicely about how to use --branch.
+                    if not self.detectBranches:
+                        if not branch_exists(self.branch):
+                            if branch_arg_given:
+                                die("Error: branch %s does not exist." % self.branch)
+                            else:
+                                die("Error: no branch %s; perhaps specify one with --branch." %
+                                    self.branch)
+
                 if self.verbose:
                     print "Getting p4 changes for %s...%s" % (', '.join(self.depotPaths),
                                                               self.changeRange)
@@ -2988,6 +3007,14 @@ def run(self, args):
 
                 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:
@@ -2998,7 +3025,7 @@ def run(self, args):
                             sys.stdout.write("%s " % b)
                         sys.stdout.write("\n")
 
-        if gitConfig("git-p4.importLabels", "--bool") == "true":
+        if gitConfigBool("git-p4.importLabels"):
             self.importLabels = True
 
         if self.importLabels:
@@ -3020,6 +3047,13 @@ def run(self, args):
                 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):
@@ -3043,7 +3077,7 @@ def rebase(self):
         if os.system("git update-index --refresh") != 0:
             die("Some files in your working directory are modified and different than what is in your index. You can use git update-index <filename> to bring the index up-to-date or stash away all your changes with git stash.");
         if len(read_pipe("git diff-index HEAD --")) > 0:
-            die("You have 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:
@@ -3055,7 +3089,7 @@ def rebase(self):
         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):
@@ -3109,6 +3143,7 @@ def run(self, args):
         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:
@@ -3129,17 +3164,15 @@ def run(self, args):
 
         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", "master", self.branch ])
+            if not self.cloneBare:
+                system([ "git", "checkout", "-f" ])
+        else:
+            print 'Not checking out any branch, use ' \
+                  '"git checkout -q -b master <branch>"'
 
         # auto-set this variable if invoked with --use-client-spec
         if self.useClientSpec_from_options: