Warn about conflicting p4 branch mappings and use the first one found.

diff --git a/contrib/fast-import/git-p4 b/contrib/fast-import/git-p4
index b3f27fe90f21158cec74e1b8c276be81d92b61a9..2040591383e93db3544b50a118f8151062591d3d 100755 (executable)
--- a/contrib/fast-import/git-p4
+++ b/contrib/fast-import/git-p4
@@ -637,6 +637,7 @@ class P4Sync(Command):
         self.isWindows = (platform.system() == "Windows")
         self.keepRepoPath = False
         self.depotPaths = None
+        self.p4BranchesInGit = []
 
         if gitConfig("git-p4.syncFromOrigin") == "false":
             self.syncWithOrigin = False
@@ -699,6 +700,7 @@ class P4Sync(Command):
                     if branch not in branches:
                         branches[branch] = []
                     branches[branch].append(file)
+                    break
 
         return branches
 
@@ -710,9 +712,23 @@ class P4Sync(Command):
         if not files:
             return
 
-        filedata = p4CmdList('print %s' % ' '.join(['"%s#%s"' % (f['path'],
-                                                                 f['rev'])
-                                                    for f in files]))
+        # We cannot put all the files on the command line
+        # OS have limitations on the max lenght of arguments
+        # POSIX says it's 4096 bytes, default for Linux seems to be 130 K.
+        # and all OS from the table below seems to be higher than POSIX.
+        # See http://www.in-ulm.de/~mascheck/various/argmax/
+        argmax = min(4000, os.sysconf('SC_ARG_MAX'))
+        chunk = ''
+        filedata = []
+        for i in xrange(len(files)):
+            f = files[i]
+            chunk += '"%s#%s" ' % (f['path'], f['rev'])
+            if len(chunk) > argmax or i == len(files)-1:
+                data = p4CmdList('print %s' % chunk)
+                if "p4ExitCode" in data[0]:
+                    die("Problems executing p4. Error: [%d]." % (data[0]['p4ExitCode']));
+                filedata.extend(data)
+                chunk = ''
 
         j = 0;
         contents = {}
@@ -923,6 +939,8 @@ class P4Sync(Command):
             return p
 
     def getBranchMapping(self):
+        lostAndFoundBranches = set()
+
         for info in p4CmdList("branches"):
             details = p4Cmd("branch -o %s" % info["branch"])
             viewIdx = 0
@@ -938,10 +956,23 @@ class P4Sync(Command):
                 if source.startswith(self.depotPaths[0]) and destination.startswith(self.depotPaths[0]):
                     source = source[len(self.depotPaths[0]):-4]
                     destination = destination[len(self.depotPaths[0]):-4]
-                    if destination not in self.knownBranches:
-                        self.knownBranches[destination] = source
+
+                    if destination in self.knownBranches:
+                        if not self.silent:
+                            print "p4 branch %s defines a mapping from %s to %s" % (info["branch"], source, destination)
+                            print "but there exists another mapping from %s to %s already!" % (self.knownBranches[destination], destination)
+                        continue
+
+                    self.knownBranches[destination] = source
+
+                    lostAndFoundBranches.discard(destination)
+
                     if source not in self.knownBranches:
-                        self.knownBranches[source] = source
+                        lostAndFoundBranches.add(source)
+
+
+        for branch in lostAndFoundBranches:
+            self.knownBranches[branch] = branch
 
     def listExistingP4GitBranches(self):
         self.p4BranchesInGit = []