Cache the output of "p4 users" for faster syncs on high latency links.
[gitweb.git] / contrib / fast-import / git-p4
index e6a34f4f478db2451de28687a55c9387d16c7c9d..e5e7c6be12d97d0ec436dbdcede040db30f3717d 100755 (executable)
@@ -8,12 +8,15 @@
 # License: MIT <http://www.opensource.org/licenses/mit-license.php>
 #
 
-import optparse, sys, os, marshal, popen2, shelve
-import tempfile, getopt, sha, os.path, time
+import optparse, sys, os, marshal, popen2, subprocess, shelve
+import tempfile, getopt, sha, os.path, time, platform
 from sets import Set;
 
 gitdir = os.environ.get("GIT_DIR", "")
 
+def mypopen(command):
+    return os.popen(command, "rb");
+
 def p4CmdList(cmd):
     cmd = "p4 -G %s" % cmd
     pipe = os.popen(cmd, "rb")
@@ -36,18 +39,37 @@ def p4Cmd(cmd):
         result.update(entry)
     return result;
 
+def p4Where(depotPath):
+    if not depotPath.endswith("/"):
+        depotPath += "/"
+    output = p4Cmd("where %s..." % depotPath)
+    clientPath = ""
+    if "path" in output:
+        clientPath = output.get("path")
+    elif "data" in output:
+        data = output.get("data")
+        lastSpace = data.rfind(" ")
+        clientPath = data[lastSpace + 1:]
+
+    if clientPath.endswith("..."):
+        clientPath = clientPath[:-3]
+    return clientPath
+
 def die(msg):
     sys.stderr.write(msg + "\n")
     sys.exit(1)
 
 def currentGitBranch():
-    return os.popen("git-name-rev HEAD").read().split(" ")[1][:-1]
+    return mypopen("git name-rev HEAD").read().split(" ")[1][:-1]
 
 def isValidGitDir(path):
     if os.path.exists(path + "/HEAD") and os.path.exists(path + "/refs") and os.path.exists(path + "/objects"):
         return True;
     return False
 
+def parseRevision(ref):
+    return mypopen("git rev-parse %s" % ref).read()[:-1]
+
 def system(cmd):
     if os.system(cmd) != 0:
         die("command failed: %s" % cmd)
@@ -55,10 +77,10 @@ def system(cmd):
 def extractLogMessageFromGitCommit(commit):
     logMessage = ""
     foundTitle = False
-    for log in os.popen("git-cat-file commit %s" % commit).readlines():
+    for log in mypopen("git cat-file commit %s" % commit).readlines():
        if not foundTitle:
            if len(log) == 1:
-               foundTitle = 1
+               foundTitle = True
            continue
 
        logMessage += log
@@ -84,11 +106,13 @@ def extractDepotPathAndChangeFromGitLog(log):
     return values.get("depot-path"), values.get("change")
 
 def gitBranchExists(branch):
-    return os.system("git-rev-parse %s 2>/dev/null >/dev/null") == 0
+    proc = subprocess.Popen(["git", "rev-parse", branch], stderr=subprocess.PIPE, stdout=subprocess.PIPE);
+    return proc.wait() == 0;
 
 class Command:
     def __init__(self):
         self.usage = "usage: %prog [options]"
+        self.needsGit = True
 
 class P4Debug(Command):
     def __init__(self):
@@ -96,73 +120,33 @@ class P4Debug(Command):
         self.options = [
         ]
         self.description = "A tool to debug the output of p4 -G."
+        self.needsGit = False
 
     def run(self, args):
         for output in p4CmdList(" ".join(args)):
             print output
         return True
 
-class P4CleanTags(Command):
-    def __init__(self):
-        Command.__init__(self)
-        self.options = [
-#                optparse.make_option("--branch", dest="branch", default="refs/heads/master")
-        ]
-        self.description = "A tool to remove stale unused tags from incremental perforce imports."
-    def run(self, args):
-        branch = currentGitBranch()
-        print "Cleaning out stale p4 import tags..."
-        sout, sin, serr = popen2.popen3("git-name-rev --tags `git-rev-parse %s`" % branch)
-        output = sout.read()
-        try:
-            tagIdx = output.index(" tags/p4/")
-        except:
-            print "Cannot find any p4/* tag. Nothing to do."
-            sys.exit(0)
-
-        try:
-            caretIdx = output.index("^")
-        except:
-            caretIdx = len(output) - 1
-        rev = int(output[tagIdx + 9 : caretIdx])
-
-        allTags = os.popen("git tag -l p4/").readlines()
-        for i in range(len(allTags)):
-            allTags[i] = int(allTags[i][3:-1])
-
-        allTags.sort()
-
-        allTags.remove(rev)
-
-        for rev in allTags:
-            print os.popen("git tag -d p4/%s" % rev).read()
-
-        print "%s tags removed." % len(allTags)
-        return True
-
-class P4Sync(Command):
+class P4Submit(Command):
     def __init__(self):
         Command.__init__(self)
         self.options = [
                 optparse.make_option("--continue", action="store_false", dest="firstTime"),
                 optparse.make_option("--origin", dest="origin"),
                 optparse.make_option("--reset", action="store_true", dest="reset"),
-                optparse.make_option("--master", dest="master"),
                 optparse.make_option("--log-substitutions", dest="substFile"),
                 optparse.make_option("--noninteractive", action="store_false"),
                 optparse.make_option("--dry-run", action="store_true"),
-                optparse.make_option("--apply-as-patch", action="store_true", dest="applyAsPatch")
         ]
         self.description = "Submit changes from git to the perforce depot."
+        self.usage += " [name of git branch to submit into perforce depot]"
         self.firstTime = True
         self.reset = False
         self.interactive = True
         self.dryRun = False
         self.substFile = ""
         self.firstTime = True
-        self.origin = "origin"
-        self.master = ""
-        self.applyAsPatch = True
+        self.origin = ""
 
         self.logSubstitutions = {}
         self.logSubstitutions["<enter description here>"] = "%log%"
@@ -174,19 +158,15 @@ class P4Sync(Command):
 
     def start(self):
         if len(self.config) > 0 and not self.reset:
-            die("Cannot start sync. Previous sync config found at %s" % self.configFile)
+            die("Cannot start sync. Previous sync config found at %s\nIf you want to start submitting again from scratch maybe you want to call git-p4 submit --reset" % self.configFile)
 
         commits = []
-        for line in os.popen("git-rev-list --no-merges %s..%s" % (self.origin, self.master)).readlines():
+        for line in mypopen("git rev-list --no-merges %s..%s" % (self.origin, self.master)).readlines():
             commits.append(line[:-1])
         commits.reverse()
 
         self.config["commits"] = commits
 
-        if not self.applyAsPatch:
-            print "Creating temporary p4-sync branch from %s ..." % self.origin
-            system("git checkout -f -b p4-sync %s" % self.origin)
-
     def prepareLogMessage(self, template, message):
         result = ""
 
@@ -211,15 +191,17 @@ class P4Sync(Command):
         return result
 
     def apply(self, id):
-        print "Applying %s" % (os.popen("git-log --max-count=1 --pretty=oneline %s" % id).read())
-        diff = os.popen("git diff-tree -r --name-status \"%s^\" \"%s\"" % (id, id)).readlines()
+        print "Applying %s" % (mypopen("git log --max-count=1 --pretty=oneline %s" % id).read())
+        diff = mypopen("git diff-tree -r --name-status \"%s^\" \"%s\"" % (id, id)).readlines()
         filesToAdd = set()
         filesToDelete = set()
+        editedFiles = set()
         for line in diff:
             modifier = line[0]
             path = line[1:].strip()
             if modifier == "M":
-                system("p4 edit %s" % path)
+                system("p4 edit \"%s\"" % path)
+                editedFiles.add(path)
             elif modifier == "A":
                 filesToAdd.add(path)
                 if path in filesToDelete:
@@ -231,11 +213,33 @@ class P4Sync(Command):
             else:
                 die("unknown modifier %s for %s" % (modifier, path))
 
-        if self.applyAsPatch:
-            system("git-diff-tree -p --diff-filter=ACMRTUXB \"%s^\" \"%s\" | patch -p1" % (id, id))
-        else:
-            system("git-diff-files --name-only -z | git-update-index --remove -z --stdin")
-            system("git cherry-pick --no-commit \"%s\"" % id)
+        diffcmd = "git diff-tree -p --diff-filter=ACMRTUXB \"%s^\" \"%s\"" % (id, id)
+        patchcmd = diffcmd + " | patch -p1"
+
+        if os.system(patchcmd + " --dry-run --silent") != 0:
+            print "Unfortunately applying the change failed!"
+            print "What do you want to do?"
+            response = "x"
+            while response != "s" and response != "a" and response != "w":
+                response = raw_input("[s]kip this patch / [a]pply the patch forcibly and with .rej files / [w]rite the patch to a file (patch.txt) ")
+            if response == "s":
+                print "Skipping! Good luck with the next patches..."
+                return
+            elif response == "a":
+                os.system(patchcmd)
+                if len(filesToAdd) > 0:
+                    print "You may also want to call p4 add on the following files:"
+                    print " ".join(filesToAdd)
+                if len(filesToDelete):
+                    print "The following files should be scheduled for deletion with p4 delete:"
+                    print " ".join(filesToDelete)
+                die("Please resolve and submit the conflict manually and continue afterwards with git-p4 submit --continue")
+            elif response == "w":
+                system(diffcmd + " > patch.txt")
+                print "Patch saved to patch.txt in %s !" % self.clientPath
+                die("Please resolve and submit the conflict manually and continue afterwards with git-p4 submit --continue")
+
+        system(patchcmd)
 
         for f in filesToAdd:
             system("p4 add %s" % f)
@@ -247,11 +251,11 @@ class P4Sync(Command):
         logMessage = logMessage.replace("\n", "\n\t")
         logMessage = logMessage[:-1]
 
-        template = os.popen("p4 change -o").read()
+        template = mypopen("p4 change -o").read()
 
         if self.interactive:
             submitTemplate = self.prepareLogMessage(template, logMessage)
-            diff = os.popen("p4 diff -du ...").read()
+            diff = mypopen("p4 diff -du ...").read()
 
             for newFile in filesToAdd:
                 diff += "==== new file ====\n"
@@ -262,22 +266,28 @@ class P4Sync(Command):
                     diff += "+" + line
                 f.close()
 
-            separatorLine = "######## everything below this line is just the diff #######\n"
+            separatorLine = "######## everything below this line is just the diff #######"
+            if platform.system() == "Windows":
+                separatorLine += "\r"
+            separatorLine += "\n"
 
             response = "e"
             firstIteration = True
             while response == "e":
                 if not firstIteration:
-                    response = raw_input("Do you want to submit this change (y/e/n)? ")
+                    response = raw_input("Do you want to submit this change? [y]es/[e]dit/[n]o/[s]kip ")
                 firstIteration = False
                 if response == "e":
                     [handle, fileName] = tempfile.mkstemp()
                     tmpFile = os.fdopen(handle, "w+")
                     tmpFile.write(submitTemplate + separatorLine + diff)
                     tmpFile.close()
-                    editor = os.environ.get("EDITOR", "vi")
+                    defaultEditor = "vi"
+                    if platform.system() == "Windows":
+                        defaultEditor = "notepad"
+                    editor = os.environ.get("EDITOR", defaultEditor);
                     system(editor + " " + fileName)
-                    tmpFile = open(fileName, "r")
+                    tmpFile = open(fileName, "rb")
                     message = tmpFile.read()
                     tmpFile.close()
                     os.remove(fileName)
@@ -288,9 +298,18 @@ class P4Sync(Command):
                    print submitTemplate
                    raw_input("Press return to continue...")
                else:
-                    pipe = os.popen("p4 submit -i", "w")
+                    pipe = os.popen("p4 submit -i", "wb")
                     pipe.write(submitTemplate)
                     pipe.close()
+            elif response == "s":
+                for f in editedFiles:
+                    system("p4 revert \"%s\"" % f);
+                for f in filesToAdd:
+                    system("p4 revert \"%s\"" % f);
+                    system("rm %s" %f)
+                for f in filesToDelete:
+                    system("p4 delete \"%s\"" % f);
+                return
             else:
                 print "Not submitting!"
                 self.interactive = False
@@ -302,6 +321,49 @@ class P4Sync(Command):
             print "Perforce submit template written as %s. Please review/edit and then use p4 submit -i < %s to submit directly!" % (fileName, fileName)
 
     def run(self, args):
+        global gitdir
+        # make gitdir absolute so we can cd out into the perforce checkout
+        gitdir = os.path.abspath(gitdir)
+        os.environ["GIT_DIR"] = gitdir
+
+        if len(args) == 0:
+            self.master = currentGitBranch()
+            if len(self.master) == 0 or not os.path.exists("%s/refs/heads/%s" % (gitdir, self.master)):
+                die("Detecting current git branch failed!")
+        elif len(args) == 1:
+            self.master = args[0]
+        else:
+            return False
+
+        depotPath = ""
+        if gitBranchExists("p4"):
+            [depotPath, dummy] = extractDepotPathAndChangeFromGitLog(extractLogMessageFromGitCommit("p4"))
+        if len(depotPath) == 0 and gitBranchExists("origin"):
+            [depotPath, dummy] = extractDepotPathAndChangeFromGitLog(extractLogMessageFromGitCommit("origin"))
+
+        if len(depotPath) == 0:
+            print "Internal error: cannot locate perforce depot path from existing branches"
+            sys.exit(128)
+
+        self.clientPath = p4Where(depotPath)
+
+        if len(self.clientPath) == 0:
+            print "Error: Cannot locate perforce checkout of %s in client view" % depotPath
+            sys.exit(128)
+
+        print "Perforce checkout for depot path %s located at %s" % (depotPath, self.clientPath)
+        oldWorkingDirectory = os.getcwd()
+        os.chdir(self.clientPath)
+        response = raw_input("Do you want to sync %s with p4 sync? [y]es/[n]o " % self.clientPath)
+        if response == "y" or response == "yes":
+            system("p4 sync ...")
+
+        if len(self.origin) == 0:
+            if gitBranchExists("p4"):
+                self.origin = "p4"
+            else:
+                self.origin = "origin"
+
         if self.reset:
             self.firstTime = True
 
@@ -310,11 +372,6 @@ class P4Sync(Command):
                 tokens = line[:-1].split("=")
                 self.logSubstitutions[tokens[0]] = tokens[1]
 
-        if len(self.master) == 0:
-            self.master = currentGitBranch()
-            if len(self.master) == 0 or not os.path.exists("%s/refs/heads/%s" % (gitdir, self.master)):
-                die("Detecting current git branch failed!")
-
         self.check()
         self.configFile = gitdir + "/p4-git-sync.cfg"
         self.config = shelve.open(self.configFile, writeback=True)
@@ -340,18 +397,16 @@ class P4Sync(Command):
                 print "No changes found to apply between %s and current HEAD" % self.origin
             else:
                 print "All changes applied!"
-                if not self.applyAsPatch:
-                    print "Deleting temporary p4-sync branch and going back to %s" % self.master
-                    system("git checkout %s" % self.master)
-                    system("git branch -D p4-sync")
-                    print "Cleaning out your perforce checkout by doing p4 edit ... ; p4 revert ..."
-                    system("p4 edit ... >/dev/null")
-                    system("p4 revert ... >/dev/null")
+                response = raw_input("Do you want to sync from Perforce now using git-p4 rebase? [y]es/[n]o ")
+                if response == "y" or response == "yes":
+                    os.chdir(oldWorkingDirectory)
+                    rebase = P4Rebase()
+                    rebase.run([])
             os.remove(self.configFile)
 
         return True
 
-class GitSync(Command):
+class P4Sync(Command):
     def __init__(self):
         Command.__init__(self)
         self.options = [
@@ -359,9 +414,9 @@ class GitSync(Command):
                 optparse.make_option("--detect-branches", dest="detectBranches", action="store_true"),
                 optparse.make_option("--changesfile", dest="changesFile"),
                 optparse.make_option("--silent", dest="silent", action="store_true"),
-                optparse.make_option("--known-branches", dest="knownBranches"),
-                optparse.make_option("--cache", dest="doCache", action="store_true"),
-                optparse.make_option("--command-cache", dest="commandCache", action="store_true")
+                optparse.make_option("--detect-labels", dest="detectLabels", action="store_true"),
+                optparse.make_option("--with-origin", dest="syncWithOrigin", action="store_true"),
+                optparse.make_option("--verbose", dest="verbose", action="store_true")
         ]
         self.description = """Imports from Perforce into a git repository.\n
     example:
@@ -373,15 +428,15 @@ class GitSync(Command):
 
         self.usage += " //depot/path[@revRange]"
 
-        self.dataCache = False
-        self.commandCache = False
         self.silent = False
-        self.knownBranches = Set()
         self.createdBranches = Set()
         self.committedChanges = Set()
         self.branch = ""
         self.detectBranches = False
+        self.detectLabels = False
         self.changesFile = ""
+        self.syncWithOrigin = False
+        self.verbose = False
 
     def p4File(self, depotPath):
         return os.popen("p4 print -q \"%s\"" % depotPath, "rb").read()
@@ -391,9 +446,9 @@ class GitSync(Command):
         fnum = 0
         while commit.has_key("depotFile%s" % fnum):
             path =  commit["depotFile%s" % fnum]
-            if not path.startswith(self.globalPrefix):
+            if not path.startswith(self.depotPath):
     #            if not self.silent:
-    #                print "\nchanged files: ignoring path %s outside of %s in change %s" % (path, self.globalPrefix, change)
+    #                print "\nchanged files: ignoring path %s outside of %s in change %s" % (path, self.depotPath, change)
                 fnum = fnum + 1
                 continue
 
@@ -406,124 +461,48 @@ class GitSync(Command):
             fnum = fnum + 1
         return files
 
-    def isSubPathOf(self, first, second):
-        if not first.startswith(second):
-            return False
-        if first == second:
-            return True
-        return first[len(second)] == "/"
+    def splitFilesIntoBranches(self, commit):
+        branches = {}
 
-    def branchesForCommit(self, files):
-        branches = Set()
-
-        for file in files:
-            relativePath = file["path"][len(self.globalPrefix):]
-            # strip off the filename
-            relativePath = relativePath[0:relativePath.rfind("/")]
-
-    #        if len(branches) == 0:
-    #            branches.add(relativePath)
-    #            knownBranches.add(relativePath)
-    #            continue
-
-            ###### this needs more testing :)
-            knownBranch = False
-            for branch in branches:
-                if relativePath == branch:
-                    knownBranch = True
-                    break
-    #            if relativePath.startswith(branch):
-                if self.isSubPathOf(relativePath, branch):
-                    knownBranch = True
-                    break
-    #            if branch.startswith(relativePath):
-                if self.isSubPathOf(branch, relativePath):
-                    branches.remove(branch)
-                    break
-
-            if knownBranch:
+        fnum = 0
+        while commit.has_key("depotFile%s" % fnum):
+            path =  commit["depotFile%s" % fnum]
+            if not path.startswith(self.depotPath):
+    #            if not self.silent:
+    #                print "\nchanged files: ignoring path %s outside of %s in change %s" % (path, self.depotPath, change)
+                fnum = fnum + 1
                 continue
 
-            for branch in knownBranches:
-                #if relativePath.startswith(branch):
-                if self.isSubPathOf(relativePath, branch):
-                    if len(branches) == 0:
-                        relativePath = branch
-                    else:
-                        knownBranch = True
-                    break
+            file = {}
+            file["path"] = path
+            file["rev"] = commit["rev%s" % fnum]
+            file["action"] = commit["action%s" % fnum]
+            file["type"] = commit["type%s" % fnum]
+            fnum = fnum + 1
 
-            if knownBranch:
-                continue
+            relPath = path[len(self.depotPath):]
 
-            branches.add(relativePath)
-            self.knownBranches.add(relativePath)
+            for branch in self.knownBranches.keys():
+                if relPath.startswith(branch):
+                    if branch not in branches:
+                        branches[branch] = []
+                    branches[branch].append(file)
 
         return branches
 
-    def findBranchParent(self, branchPrefix, files):
-        for file in files:
-            path = file["path"]
-            if not path.startswith(branchPrefix):
-                continue
-            action = file["action"]
-            if action != "integrate" and action != "branch":
-                continue
-            rev = file["rev"]
-            depotPath = path + "#" + rev
-
-            log = p4CmdList("filelog \"%s\"" % depotPath)
-            if len(log) != 1:
-                print "eek! I got confused by the filelog of %s" % depotPath
-                sys.exit(1);
-
-            log = log[0]
-            if log["action0"] != action:
-                print "eek! wrong action in filelog for %s : found %s, expected %s" % (depotPath, log["action0"], action)
-                sys.exit(1);
-
-            branchAction = log["how0,0"]
-    #        if branchAction == "branch into" or branchAction == "ignored":
-    #            continue # ignore for branching
-
-            if not branchAction.endswith(" from"):
-                continue # ignore for branching
-    #            print "eek! file %s was not branched from but instead: %s" % (depotPath, branchAction)
-    #            sys.exit(1);
-
-            source = log["file0,0"]
-            if source.startswith(branchPrefix):
-                continue
-
-            lastSourceRev = log["erev0,0"]
-
-            sourceLog = p4CmdList("filelog -m 1 \"%s%s\"" % (source, lastSourceRev))
-            if len(sourceLog) != 1:
-                print "eek! I got confused by the source filelog of %s%s" % (source, lastSourceRev)
-                sys.exit(1);
-            sourceLog = sourceLog[0]
-
-            relPath = source[len(self.globalPrefix):]
-            # strip off the filename
-            relPath = relPath[0:relPath.rfind("/")]
-
-            for branch in self.knownBranches:
-                if self.isSubPathOf(relPath, branch):
-    #                print "determined parent branch branch %s due to change in file %s" % (branch, source)
-                    return branch
-    #            else:
-    #                print "%s is not a subpath of branch %s" % (relPath, branch)
-
-        return ""
-
-    def commit(self, details, files, branch, branchPrefix, parent = "", merged = ""):
+    def commit(self, details, files, branch, branchPrefix, parent = ""):
         epoch = details["time"]
         author = details["user"]
 
+        if self.verbose:
+            print "commit into %s" % branch
+
         self.gitStream.write("commit %s\n" % branch)
     #    gitStream.write("mark :%s\n" % details["change"])
         self.committedChanges.add(int(details["change"]))
         committer = ""
+        if author not in self.users:
+            self.getUserMapFromPerforceServer()
         if author in self.users:
             committer = "%s %s %s" % (self.users[author], epoch, self.tz)
         else:
@@ -537,11 +516,10 @@ class GitSync(Command):
         self.gitStream.write("EOT\n\n")
 
         if len(parent) > 0:
+            if self.verbose:
+                print "parent %s" % parent
             self.gitStream.write("from %s\n" % parent)
 
-        if len(merged) > 0:
-            self.gitStream.write("merge %s\n" % merged)
-
         for file in files:
             path = file["path"]
             if not path.startswith(branchPrefix):
@@ -573,230 +551,285 @@ class GitSync(Command):
 
         self.gitStream.write("\n")
 
-        self.lastChange = int(details["change"])
+        change = int(details["change"])
 
-    def extractFilesInCommitToBranch(self, files, branchPrefix):
-        newFiles = []
+        if self.labels.has_key(change):
+            label = self.labels[change]
+            labelDetails = label[0]
+            labelRevisions = label[1]
+            if self.verbose:
+                print "Change %s is labelled %s" % (change, labelDetails)
 
-        for file in files:
-            path = file["path"]
-            if path.startswith(branchPrefix):
-                newFiles.append(file)
+            files = p4CmdList("files %s...@%s" % (branchPrefix, change))
 
-        return newFiles
+            if len(files) == len(labelRevisions):
 
-    def findBranchSourceHeuristic(self, files, branch, branchPrefix):
-        for file in files:
-            action = file["action"]
-            if action != "integrate" and action != "branch":
-                continue
-            path = file["path"]
-            rev = file["rev"]
-            depotPath = path + "#" + rev
+                cleanedFiles = {}
+                for info in files:
+                    if info["action"] == "delete":
+                        continue
+                    cleanedFiles[info["depotFile"]] = info["rev"]
 
-            log = p4CmdList("filelog \"%s\"" % depotPath)
-            if len(log) != 1:
-                print "eek! I got confused by the filelog of %s" % depotPath
-                sys.exit(1);
-
-            log = log[0]
-            if log["action0"] != action:
-                print "eek! wrong action in filelog for %s : found %s, expected %s" % (depotPath, log["action0"], action)
-                sys.exit(1);
-
-            branchAction = log["how0,0"]
-
-            if not branchAction.endswith(" from"):
-                continue # ignore for branching
-    #            print "eek! file %s was not branched from but instead: %s" % (depotPath, branchAction)
-    #            sys.exit(1);
-
-            source = log["file0,0"]
-            if source.startswith(branchPrefix):
-                continue
+                if cleanedFiles == labelRevisions:
+                    self.gitStream.write("tag tag_%s\n" % labelDetails["label"])
+                    self.gitStream.write("from %s\n" % branch)
 
-            lastSourceRev = log["erev0,0"]
-
-            sourceLog = p4CmdList("filelog -m 1 \"%s%s\"" % (source, lastSourceRev))
-            if len(sourceLog) != 1:
-                print "eek! I got confused by the source filelog of %s%s" % (source, lastSourceRev)
-                sys.exit(1);
-            sourceLog = sourceLog[0]
+                    owner = labelDetails["Owner"]
+                    tagger = ""
+                    if author in self.users:
+                        tagger = "%s %s %s" % (self.users[owner], epoch, self.tz)
+                    else:
+                        tagger = "%s <a@b> %s %s" % (owner, epoch, self.tz)
+                    self.gitStream.write("tagger %s\n" % tagger)
+                    self.gitStream.write("data <<EOT\n")
+                    self.gitStream.write(labelDetails["Description"])
+                    self.gitStream.write("EOT\n\n")
 
-            relPath = source[len(self.globalPrefix):]
-            # strip off the filename
-            relPath = relPath[0:relPath.rfind("/")]
+                else:
+                    if not self.silent:
+                        print "Tag %s does not match with change %s: files do not match." % (labelDetails["label"], change)
 
-            for candidate in self.knownBranches:
-                if self.isSubPathOf(relPath, candidate) and candidate != branch:
-                    return candidate
+            else:
+                if not self.silent:
+                    print "Tag %s does not match with change %s: file count is different." % (labelDetails["label"], change)
 
-        return ""
+    def getUserMapFromPerforceServer(self):
+        self.users = {}
 
-    def changeIsBranchMerge(self, sourceBranch, destinationBranch, change):
-        sourceFiles = {}
-        for file in p4CmdList("files %s...@%s" % (self.globalPrefix + sourceBranch + "/", change)):
-            if file["action"] == "delete":
+        for output in p4CmdList("users"):
+            if not output.has_key("User"):
                 continue
-            sourceFiles[file["depotFile"]] = file
-
-        destinationFiles = {}
-        for file in p4CmdList("files %s...@%s" % (self.globalPrefix + destinationBranch + "/", change)):
-            destinationFiles[file["depotFile"]] = file
-
-        for fileName in sourceFiles.keys():
-            integrations = []
-            deleted = False
-            integrationCount = 0
-            for integration in p4CmdList("integrated \"%s\"" % fileName):
-                toFile = integration["fromFile"] # yes, it's true, it's fromFile
-                if not toFile in destinationFiles:
-                    continue
-                destFile = destinationFiles[toFile]
-                if destFile["action"] == "delete":
-    #                print "file %s has been deleted in %s" % (fileName, toFile)
-                    deleted = True
-                    break
-                integrationCount += 1
-                if integration["how"] == "branch from":
-                    continue
-
-                if int(integration["change"]) == change:
-                    integrations.append(integration)
-                    continue
-                if int(integration["change"]) > change:
-                    continue
+            self.users[output["User"]] = output["FullName"] + " <" + output["Email"] + ">"
 
-                destRev = int(destFile["rev"])
+        cache = open(gitdir + "/p4-usercache.txt", "wb")
+        for user in self.users.keys():
+            cache.write("%s\t%s\n" % (user, self.users[user]))
+        cache.close();
 
-                startRev = integration["startFromRev"][1:]
-                if startRev == "none":
-                    startRev = 0
-                else:
-                    startRev = int(startRev)
+    def loadUserMapFromCache(self):
+        self.users = {}
+        try:
+            cache = open(gitdir + "/p4-usercache.txt", "rb")
+            lines = cache.readlines()
+            cache.close()
+            for line in lines:
+                entry = line[:-1].split("\t")
+                self.users[entry[0]] = entry[1]
+        except IOError:
+            self.getUserMapFromPerforceServer()
+
+    def getLabels(self):
+        self.labels = {}
+
+        l = p4CmdList("labels %s..." % self.depotPath)
+        if len(l) > 0 and not self.silent:
+            print "Finding files belonging to labels in %s" % self.depotPath
+
+        for output in l:
+            label = output["label"]
+            revisions = {}
+            newestChange = 0
+            if self.verbose:
+                print "Querying files for label %s" % label
+            for file in p4CmdList("files %s...@%s" % (self.depotPath, label)):
+                revisions[file["depotFile"]] = file["rev"]
+                change = int(file["change"])
+                if change > newestChange:
+                    newestChange = change
+
+            self.labels[newestChange] = [output, revisions]
+
+        if self.verbose:
+            print "Label changes: %s" % self.labels.keys()
+
+    def getBranchMapping(self):
+        self.projectName = self.depotPath[self.depotPath[:-1].rfind("/") + 1:]
+
+        for info in p4CmdList("branches"):
+            details = p4Cmd("branch -o %s" % info["branch"])
+            viewIdx = 0
+            while details.has_key("View%s" % viewIdx):
+                paths = details["View%s" % viewIdx].split(" ")
+                viewIdx = viewIdx + 1
+                # require standard //depot/foo/... //depot/bar/... mapping
+                if len(paths) != 2 or not paths[0].endswith("/...") or not paths[1].endswith("/..."):
+                    continue
+                source = paths[0]
+                destination = paths[1]
+                if source.startswith(self.depotPath) and destination.startswith(self.depotPath):
+                    source = source[len(self.depotPath):-4]
+                    destination = destination[len(self.depotPath):-4]
+                    if destination not in self.knownBranches:
+                        self.knownBranches[destination] = source
+                    if source not in self.knownBranches:
+                        self.knownBranches[source] = source
+
+    def listExistingP4GitBranches(self):
+        self.p4BranchesInGit = []
+
+        for line in mypopen("git rev-parse --symbolic --remotes").readlines():
+            if line.startswith("p4/") and line != "p4/HEAD\n":
+                branch = line[3:-1]
+                self.p4BranchesInGit.append(branch)
+                self.initialParents["refs/remotes/p4/" + branch] = parseRevision(line[:-1])
 
-                endRev = integration["endFromRev"][1:]
-                if endRev == "none":
-                    endRev = 0
+    def run(self, args):
+        self.depotPath = ""
+        self.changeRange = ""
+        self.initialParent = ""
+        self.previousDepotPath = ""
+        # map from branch depot path to parent branch
+        self.knownBranches = {}
+        self.initialParents = {}
+
+        self.listExistingP4GitBranches()
+
+        if self.syncWithOrigin and gitBranchExists("origin") and gitBranchExists("refs/remotes/p4/master") and not self.detectBranches:
+            ### needs to be ported to multi branch import
+
+            print "Syncing with origin first as requested by calling git fetch origin"
+            system("git fetch origin")
+            [originPreviousDepotPath, originP4Change] = extractDepotPathAndChangeFromGitLog(extractLogMessageFromGitCommit("origin"))
+            [p4PreviousDepotPath, p4Change] = extractDepotPathAndChangeFromGitLog(extractLogMessageFromGitCommit("p4"))
+            if len(originPreviousDepotPath) > 0 and len(originP4Change) > 0 and len(p4Change) > 0:
+                if originPreviousDepotPath == p4PreviousDepotPath:
+                    originP4Change = int(originP4Change)
+                    p4Change = int(p4Change)
+                    if originP4Change > p4Change:
+                        print "origin (%s) is newer than p4 (%s). Updating p4 branch from origin." % (originP4Change, p4Change)
+                        system("git update-ref refs/remotes/p4/master origin");
                 else:
-                    endRev = int(endRev)
-
-                initialBranch = (destRev == 1 and integration["how"] != "branch into")
-                inRange = (destRev >= startRev and destRev <= endRev)
-                newer = (destRev > startRev and destRev > endRev)
+                    print "Cannot sync with origin. It was imported from %s while remotes/p4 was imported from %s" % (originPreviousDepotPath, p4PreviousDepotPath)
 
-                if initialBranch or inRange or newer:
-                    integrations.append(integration)
+        if len(self.branch) == 0:
+            self.branch = "refs/remotes/p4/master"
+            if gitBranchExists("refs/heads/p4"):
+                system("git update-ref %s refs/heads/p4" % self.branch)
+                system("git branch -D p4");
+            if not gitBranchExists("refs/remotes/p4/HEAD"):
+                system("git symbolic-ref refs/remotes/p4/HEAD %s" % self.branch)
+
+        if len(args) == 0:
+            if not gitBranchExists(self.branch) and gitBranchExists("origin") and not self.detectBranches:
+                ### needs to be ported to multi branch import
+                if not self.silent:
+                    print "Creating %s branch in git repository based on origin" % self.branch
+                branch = self.branch
+                if not branch.startswith("refs"):
+                    branch = "refs/heads/" + branch
+                system("git update-ref %s origin" % branch)
 
-            if deleted:
-                continue
+            if self.verbose:
+                print "branches: %s" % self.p4BranchesInGit
 
-            if len(integrations) == 0 and integrationCount > 1:
-                print "file %s was not integrated from %s into %s" % (fileName, sourceBranch, destinationBranch)
-                return False
+            p4Change = 0
+            for branch in self.p4BranchesInGit:
+                depotPath, change = extractDepotPathAndChangeFromGitLog(extractLogMessageFromGitCommit("refs/remotes/p4/" + branch))
 
-        return True
+                if self.verbose:
+                    print "path %s change %s" % (depotPath, change)
 
-    def getUserMap(self):
-        self.users = {}
+                if len(depotPath) > 0 and len(change) > 0:
+                    change = int(change) + 1
+                    p4Change = max(p4Change, change)
 
-        for output in p4CmdList("users"):
-            if not output.has_key("User"):
-                continue
-            self.users[output["User"]] = output["FullName"] + " <" + output["Email"] + ">"
+                    if len(self.previousDepotPath) == 0:
+                        self.previousDepotPath = depotPath
+                    else:
+                        i = 0
+                        l = min(len(self.previousDepotPath), len(depotPath))
+                        while i < l and self.previousDepotPath[i] == depotPath[i]:
+                            i = i + 1
+                        self.previousDepotPath = self.previousDepotPath[:i]
+
+            if p4Change > 0:
+                self.depotPath = self.previousDepotPath
+                self.changeRange = "@%s,#head" % p4Change
+                self.initialParent = parseRevision(self.branch)
+                if not self.silent:
+                    print "Performing incremental import into %s git branch" % self.branch
 
-    def run(self, args):
-        if len(self.branch) == 0:
-            self.branch = "p4"
+        if not self.branch.startswith("refs/"):
+            self.branch = "refs/heads/" + self.branch
 
-        self.branch = "refs/heads/" + self.branch
-        self.globalPrefix = self.previousDepotPath = os.popen("git-repo-config --get p4.depotpath").read()
-        if len(self.globalPrefix) != 0:
-            self.globalPrefix = self.globalPrefix[:-1]
+        if len(self.depotPath) != 0:
+            self.depotPath = self.depotPath[:-1]
 
-        if len(args) == 0 and len(self.globalPrefix) != 0:
+        if len(args) == 0 and len(self.depotPath) != 0:
             if not self.silent:
-                print "[using previously specified depot path %s]" % self.globalPrefix
+                print "Depot path: %s" % self.depotPath
         elif len(args) != 1:
             return False
         else:
-            if len(self.globalPrefix) != 0 and self.globalPrefix != args[0]:
-                print "previous import used depot path %s and now %s was specified. this doesn't work!" % (self.globalPrefix, args[0])
+            if len(self.depotPath) != 0 and self.depotPath != args[0]:
+                print "previous import used depot path %s and now %s was specified. this doesn't work!" % (self.depotPath, args[0])
                 sys.exit(1)
-            self.globalPrefix = args[0]
+            self.depotPath = args[0]
 
-        self.changeRange = ""
         self.revision = ""
         self.users = {}
-        self.initialParent = ""
-        self.lastChange = 0
-        self.initialTag = ""
 
-        if self.globalPrefix.find("@") != -1:
-            atIdx = self.globalPrefix.index("@")
-            self.changeRange = self.globalPrefix[atIdx:]
+        if self.depotPath.find("@") != -1:
+            atIdx = self.depotPath.index("@")
+            self.changeRange = self.depotPath[atIdx:]
             if self.changeRange == "@all":
                 self.changeRange = ""
             elif self.changeRange.find(",") == -1:
                 self.revision = self.changeRange
                 self.changeRange = ""
-            self.globalPrefix = self.globalPrefix[0:atIdx]
-        elif self.globalPrefix.find("#") != -1:
-            hashIdx = self.globalPrefix.index("#")
-            self.revision = self.globalPrefix[hashIdx:]
-            self.globalPrefix = self.globalPrefix[0:hashIdx]
+            self.depotPath = self.depotPath[0:atIdx]
+        elif self.depotPath.find("#") != -1:
+            hashIdx = self.depotPath.index("#")
+            self.revision = self.depotPath[hashIdx:]
+            self.depotPath = self.depotPath[0:hashIdx]
         elif len(self.previousDepotPath) == 0:
             self.revision = "#head"
 
-        if self.globalPrefix.endswith("..."):
-            self.globalPrefix = self.globalPrefix[:-3]
+        if self.depotPath.endswith("..."):
+            self.depotPath = self.depotPath[:-3]
 
-        if not self.globalPrefix.endswith("/"):
-            self.globalPrefix += "/"
+        if not self.depotPath.endswith("/"):
+            self.depotPath += "/"
 
-        self.getUserMap()
+        self.loadUserMapFromCache()
+        self.labels = {}
+        if self.detectLabels:
+            self.getLabels();
 
-        if len(self.changeRange) == 0:
-            try:
-                sout, sin, serr = popen2.popen3("git-name-rev --tags `git-rev-parse %s`" % self.branch)
-                output = sout.read()
-                if output.endswith("\n"):
-                    output = output[:-1]
-                tagIdx = output.index(" tags/p4/")
-                caretIdx = output.find("^")
-                endPos = len(output)
-                if caretIdx != -1:
-                    endPos = caretIdx
-                self.rev = int(output[tagIdx + 9 : endPos]) + 1
-                self.changeRange = "@%s,#head" % self.rev
-                self.initialParent = os.popen("git-rev-parse %s" % self.branch).read()[:-1]
-                self.initialTag = "p4/%s" % (int(self.rev) - 1)
-            except:
-                pass
-
-        self.tz = - time.timezone / 36
-        tzsign = ("%s" % self.tz)[0]
-        if tzsign != '+' and tzsign != '-':
-            self.tz = "+" + ("%s" % self.tz)
-
-        self.gitOutput, self.gitStream, self.gitError = popen2.popen3("git-fast-import")
+        if self.detectBranches:
+            self.getBranchMapping();
+            if self.verbose:
+                print "p4-git branches: %s" % self.p4BranchesInGit
+                print "initial parents: %s" % self.initialParents
+            for b in self.p4BranchesInGit:
+                if b != "master":
+                    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 len(self.revision) > 0:
-            print "Doing initial import of %s from revision %s" % (self.globalPrefix, self.revision)
+            print "Doing initial import of %s from revision %s" % (self.depotPath, self.revision)
 
             details = { "user" : "git perforce import user", "time" : int(time.time()) }
-            details["desc"] = "Initial import of %s from the state at revision %s" % (self.globalPrefix, self.revision)
+            details["desc"] = "Initial import of %s from the state at revision %s" % (self.depotPath, self.revision)
             details["change"] = self.revision
             newestRevision = 0
 
             fileCnt = 0
-            for info in p4CmdList("files %s...%s" % (self.globalPrefix, self.revision)):
+            for info in p4CmdList("files %s...%s" % (self.depotPath, self.revision)):
                 change = int(info["change"])
                 if change > newestRevision:
                     newestRevision = change
 
                 if info["action"] == "delete":
-                    fileCnt = fileCnt + 1
+                    # don't increase the file cnt, otherwise details["depotFile123"] will have gaps!
+                    #fileCnt = fileCnt + 1
                     continue
 
                 for prop in [ "depotFile", "rev", "action", "type" ]:
@@ -807,8 +840,9 @@ class GitSync(Command):
             details["change"] = newestRevision
 
             try:
-                self.commit(details, self.extractFilesFromCommit(details), self.branch, self.globalPrefix)
+                self.commit(details, self.extractFilesFromCommit(details), self.branch, self.depotPath)
             except IOError:
+                print "IO error with git fast-import. Is your git version recent enough?"
                 print self.gitError.read()
 
         else:
@@ -825,7 +859,9 @@ class GitSync(Command):
 
                 changes.sort()
             else:
-                output = os.popen("p4 changes %s...%s" % (self.globalPrefix, self.changeRange)).readlines()
+                if self.verbose:
+                    print "Getting p4 changes for %s...%s" % (self.depotPath, self.changeRange)
+                output = mypopen("p4 changes %s...%s" % (self.depotPath, self.changeRange)).readlines()
 
                 for line in output:
                     changeNum = line.split(" ")[1]
@@ -836,7 +872,7 @@ class GitSync(Command):
             if len(changes) == 0:
                 if not self.silent:
                     print "no changes to import!"
-                sys.exit(1)
+                return True
 
             cnt = 1
             for change in changes:
@@ -848,40 +884,52 @@ class GitSync(Command):
                 cnt = cnt + 1
 
                 try:
-                    files = self.extractFilesFromCommit(description)
                     if self.detectBranches:
-                        for branch in self.branchesForCommit(files):
-                            self.knownBranches.add(branch)
-                            branchPrefix = self.globalPrefix + branch + "/"
+                        branches = self.splitFilesIntoBranches(description)
+                        for branch in branches.keys():
+                            branchPrefix = self.depotPath + branch + "/"
 
-                            filesForCommit = self.extractFilesInCommitToBranch(files, branchPrefix)
-
-                            merged = ""
                             parent = ""
-                            ########### remove cnt!!!
-                            if branch not in self.createdBranches and cnt > 2:
+
+                            filesForCommit = branches[branch]
+
+                            if self.verbose:
+                                print "branch is %s" % branch
+
+                            if branch not in self.createdBranches:
                                 self.createdBranches.add(branch)
-                                parent = self.findBranchParent(branchPrefix, files)
+                                parent = self.knownBranches[branch]
                                 if parent == branch:
                                     parent = ""
-            #                    elif len(parent) > 0:
-            #                        print "%s branched off of %s" % (branch, parent)
+                                elif self.verbose:
+                                    print "parent determined through known branches: %s" % parent
+
+                            # main branch? use master
+                            if branch == "main":
+                                branch = "master"
+                            else:
+                                branch = self.projectName + branch
 
-                            if len(parent) == 0:
-                                merged = self.findBranchSourceHeuristic(filesForCommit, branch, branchPrefix)
-                                if len(merged) > 0:
-                                    print "change %s could be a merge from %s into %s" % (description["change"], merged, branch)
-                                    if not self.changeIsBranchMerge(merged, branch, int(description["change"])):
-                                        merged = ""
+                            if parent == "main":
+                                parent = "master"
+                            elif len(parent) > 0:
+                                parent = self.projectName + parent
 
-                            branch = "refs/heads/" + branch
+                            branch = "refs/remotes/p4/" + branch
                             if len(parent) > 0:
-                                parent = "refs/heads/" + parent
-                            if len(merged) > 0:
-                                merged = "refs/heads/" + merged
-                            self.commit(description, files, branch, branchPrefix, parent, merged)
+                                parent = "refs/remotes/p4/" + parent
+
+                            if self.verbose:
+                                print "looking for initial parent for %s; current parent is %s" % (branch, parent)
+
+                            if len(parent) == 0 and branch in self.initialParents:
+                                parent = self.initialParents[branch]
+                                del self.initialParents[branch]
+
+                            self.commit(description, filesForCommit, branch, branchPrefix, parent)
                     else:
-                        self.commit(description, files, self.branch, self.globalPrefix, self.initialParent)
+                        files = self.extractFilesFromCommit(description)
+                        self.commit(description, files, self.branch, self.depotPath, self.initialParent)
                         self.initialParent = ""
                 except IOError:
                     print self.gitError.read()
@@ -890,18 +938,83 @@ class GitSync(Command):
         if not self.silent:
             print ""
 
-        self.gitStream.write("reset refs/tags/p4/%s\n" % self.lastChange)
-        self.gitStream.write("from %s\n\n" % self.branch);
-
 
         self.gitStream.close()
+        if importProcess.wait() != 0:
+            die("fast-import failed: %s" % self.gitError.read())
         self.gitOutput.close()
         self.gitError.close()
 
-        os.popen("git-repo-config p4.depotpath %s" % self.globalPrefix).read()
-        if len(self.initialTag) > 0:
-            os.popen("git tag -d %s" % self.initialTag).read()
+        return True
+
+class P4Rebase(Command):
+    def __init__(self):
+        Command.__init__(self)
+        self.options = [ optparse.make_option("--with-origin", dest="syncWithOrigin", action="store_true") ]
+        self.description = "Fetches the latest revision from perforce and rebases the current work (branch) against it"
+        self.syncWithOrigin = False
 
+    def run(self, args):
+        sync = P4Sync()
+        sync.syncWithOrigin = self.syncWithOrigin
+        sync.run([])
+        print "Rebasing the current branch"
+        oldHead = mypopen("git rev-parse HEAD").read()[:-1]
+        system("git rebase p4")
+        system("git diff-tree --stat --summary -M %s HEAD" % oldHead)
+        return True
+
+class P4Clone(P4Sync):
+    def __init__(self):
+        P4Sync.__init__(self)
+        self.description = "Creates a new git repository and imports from Perforce into it"
+        self.usage = "usage: %prog [options] //depot/path[@revRange] [directory]"
+        self.needsGit = False
+
+    def run(self, args):
+        if len(args) < 1:
+            return False
+        depotPath = args[0]
+        dir = ""
+        if len(args) == 2:
+            dir = args[1]
+        elif len(args) > 2:
+            return False
+
+        if not depotPath.startswith("//"):
+            return False
+
+        if len(dir) == 0:
+            dir = depotPath
+            atPos = dir.rfind("@")
+            if atPos != -1:
+                dir = dir[0:atPos]
+            hashPos = dir.rfind("#")
+            if hashPos != -1:
+                dir = dir[0:hashPos]
+
+            if dir.endswith("..."):
+                dir = dir[:-3]
+
+            if dir.endswith("/"):
+               dir = dir[:-1]
+
+            slashPos = dir.rfind("/")
+            if slashPos != -1:
+                dir = dir[slashPos + 1:]
+
+        print "Importing from %s into %s" % (depotPath, dir)
+        os.makedirs(dir)
+        os.chdir(dir)
+        system("git init")
+        if not P4Sync.run(self, [depotPath]):
+            return False
+        if self.branch != "master":
+            if gitBranchExists("refs/remotes/p4/master"):
+                system("git branch master refs/remotes/p4/master")
+                system("git checkout -f")
+            else:
+                print "Could not detect main branch. No checkout/master branch created."
         return True
 
 class HelpFormatter(optparse.IndentedHelpFormatter):
@@ -924,9 +1037,10 @@ def printUsage(commands):
 
 commands = {
     "debug" : P4Debug(),
-    "clean-tags" : P4CleanTags(),
-    "submit" : P4Sync(),
-    "sync" : GitSync()
+    "submit" : P4Submit(),
+    "sync" : P4Sync(),
+    "rebase" : P4Rebase(),
+    "clone" : P4Clone()
 }
 
 if len(sys.argv[1:]) == 0:
@@ -945,30 +1059,37 @@ except KeyError:
 
 options = cmd.options
 cmd.gitdir = gitdir
-options.append(optparse.make_option("--git-dir", dest="gitdir"))
 
-parser = optparse.OptionParser(cmd.usage.replace("%prog", "%prog " + cmdName),
-                               options,
-                               description = cmd.description,
-                               formatter = HelpFormatter())
+args = sys.argv[2:]
 
-(cmd, args) = parser.parse_args(sys.argv[2:], cmd);
+if len(options) > 0:
+    options.append(optparse.make_option("--git-dir", dest="gitdir"))
 
-gitdir = cmd.gitdir
-if len(gitdir) == 0:
-    gitdir = ".git"
-    if not isValidGitDir(gitdir):
-        cdup = os.popen("git-rev-parse --show-cdup").read()[:-1]
-        if isValidGitDir(cdup + "/" + gitdir):
-            os.chdir(cdup)
+    parser = optparse.OptionParser(cmd.usage.replace("%prog", "%prog " + cmdName),
+                                   options,
+                                   description = cmd.description,
+                                   formatter = HelpFormatter())
+
+    (cmd, args) = parser.parse_args(sys.argv[2:], cmd);
+
+if cmd.needsGit:
+    gitdir = cmd.gitdir
+    if len(gitdir) == 0:
+        gitdir = ".git"
+        if not isValidGitDir(gitdir):
+            gitdir = mypopen("git rev-parse --git-dir").read()[:-1]
+            if os.path.exists(gitdir):
+                cdup = mypopen("git rev-parse --show-cdup").read()[:-1];
+                if len(cdup) > 0:
+                    os.chdir(cdup);
 
-if not isValidGitDir(gitdir):
-    if isValidGitDir(gitdir + "/.git"):
-        gitdir += "/.git"
-    else:
-        die("fatal: cannot locate git repository at %s" % gitdir)
+    if not isValidGitDir(gitdir):
+        if isValidGitDir(gitdir + "/.git"):
+            gitdir += "/.git"
+        else:
+            die("fatal: cannot locate git repository at %s" % gitdir)
 
-os.environ["GIT_DIR"] = gitdir
+    os.environ["GIT_DIR"] = gitdir
 
 if not cmd.run(args):
     parser.print_help()