git-p4: avoid crash adding symlinked directory

When submitting to P4, if git-p4 came across a symlinked
directory, then during the generation of the submit diff, it would
try to open it as a normal file and fail.

Spot symlinks (of any type) and output a description of the symlink
instead.

Add a test case.

Signed-off-by: Luke Diamand <luke@diamand.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 20 insertions, 6 deletions

diff --git a/git-p4.py b/git-p4.py
index fd5ca5246..16d0b8a6e 100755
--- a/git-p4.py
+++ b/git-p4.py
@@ -25,6 +25,7 @@ import stat
 import zipfile
 import zlib
 import ctypes
+import errno
 
 try:
     from subprocess import CalledProcessError
@@ -1538,7 +1539,7 @@ class P4Submit(Command, P4UserMap):
             if response == 'n':
                 return False
 
-    def get_diff_description(self, editedFiles, filesToAdd):
+    def get_diff_description(self, editedFiles, filesToAdd, symlinks):
         # diff
         if os.environ.has_key("P4DIFF"):
             del(os.environ["P4DIFF"])
@@ -1553,10 +1554,17 @@ class P4Submit(Command, P4UserMap):
             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()
+
+            is_link = os.path.islink(newFile)
+            expect_link = newFile in symlinks
+
+            if is_link and expect_link:
+                newdiff += "+%s\n" % os.readlink(newFile)
+            else:
+                f = open(newFile, "r")
+                for line in f.readlines():
+                    newdiff += "+" + line
+                f.close()
 
         return (diff + newdiff).replace('\r\n', '\n')
 
@@ -1574,6 +1582,7 @@ class P4Submit(Command, P4UserMap):
         filesToDelete = set()
         editedFiles = set()
         pureRenameCopy = set()
+        symlinks = set()
         filesToChangeExecBit = {}
 
         for line in diff:
@@ -1590,6 +1599,11 @@ class P4Submit(Command, P4UserMap):
                 filesToChangeExecBit[path] = diff['dst_mode']
                 if path in filesToDelete:
                     filesToDelete.remove(path)
+
+                dst_mode = int(diff['dst_mode'], 8)
+                if dst_mode == 0120000:
+                    symlinks.add(path)
+
             elif modifier == "D":
                 filesToDelete.add(path)
                 if path in filesToAdd:
@@ -1727,7 +1741,7 @@ class P4Submit(Command, P4UserMap):
         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)
+            submitTemplate += self.get_diff_description(editedFiles, filesToAdd, symlinks)
 
         (handle, fileName) = tempfile.mkstemp()
         tmpFile = os.fdopen(handle, "w+b")