index: improve constness for reading blob data

diff --git a/git-p4.py b/git-p4.py
index 13bf44768b352c2cd5b34e718bdc7aaef7d6014d..22e3f57e7d93783ef6bb3f0bfd4ef2f6bbd0f93f 100755 (executable)
--- a/git-p4.py
+++ b/git-p4.py
@@ -25,6 +25,7 @@
 import zipfile
 import zlib
 import ctypes
+import errno
 
 try:
     from subprocess import CalledProcessError
@@ -90,6 +91,16 @@ def p4_build_cmd(cmd):
         real_cmd += cmd
     return real_cmd
 
+def git_dir(path):
+    """ Return TRUE if the given path is a git directory (/path/to/dir/.git).
+        This won't automatically add ".git" to a directory.
+    """
+    d = read_pipe(["git", "--git-dir", path, "rev-parse", "--git-dir"], True).strip()
+    if not d or len(d) == 0:
+        return None
+    else:
+        return d
+
 def chdir(path, is_client_path=False):
     """Do chdir to the given path, and set the PWD environment
        variable for use by P4.  It does not look at getcwd() output.
@@ -572,10 +583,7 @@ def currentGitBranch():
         return read_pipe(["git", "name-rev", "HEAD"]).split(" ")[1].strip()
 
 def isValidGitDir(path):
-    if (os.path.exists(path + "/HEAD")
-        and os.path.exists(path + "/refs") and os.path.exists(path + "/objects")):
-        return True;
-    return False
+    return git_dir(path) != None
 
 def parseRevision(ref):
     return read_pipe("git rev-parse %s" % ref).strip()
@@ -831,7 +839,7 @@ def p4ChangesForPaths(depotPaths, changeRange, requestedBlockSize):
                 die("cannot use --changes-block-size with non-numeric revisions")
             block_size = None
 
-    changes = []
+    changes = set()
 
     # Retrieve changes a block at a time, to prevent running
     # into a MaxResults/MaxScanRows error from the server.
@@ -850,7 +858,7 @@ def p4ChangesForPaths(depotPaths, changeRange, requestedBlockSize):
 
         # Insert changes in chronological order
         for line in reversed(p4_read_pipe_lines(cmd)):
-            changes.append(int(line.split(" ")[1]))
+            changes.add(int(line.split(" ")[1]))
 
         if not block_size:
             break
@@ -1112,10 +1120,10 @@ def generateGitAttributes(self):
                 '# Git LFS (see https://git-lfs.github.com/)\n',
                 '#\n',
             ] +
-            ['*.' + f.replace(' ', '[[:space:]]') + ' filter=lfs -text\n'
+            ['*.' + f.replace(' ', '[[:space:]]') + ' filter=lfs diff=lfs merge=lfs -text\n'
                 for f in sorted(gitConfigList('git-p4.largeFileExtensions'))
             ] +
-            ['/' + f.replace(' ', '[[:space:]]') + ' filter=lfs -text\n'
+            ['/' + f.replace(' ', '[[:space:]]') + ' filter=lfs diff=lfs merge=lfs -text\n'
                 for f in sorted(self.largeFiles) if not self.hasLargeFileExtension(f)
             ]
         )
@@ -1564,7 +1572,7 @@ def edit_template(self, template_file):
             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"])
@@ -1579,10 +1587,17 @@ def get_diff_description(self, editedFiles, 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()
+
+            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')
 
@@ -1600,6 +1615,7 @@ def applyCommit(self, id):
         filesToDelete = set()
         editedFiles = set()
         pureRenameCopy = set()
+        symlinks = set()
         filesToChangeExecBit = {}
         all_files = list()
 
@@ -1619,6 +1635,11 @@ def applyCommit(self, id):
                 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:
@@ -1760,7 +1781,7 @@ def applyCommit(self, id):
         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")
@@ -3725,6 +3746,7 @@ def main():
         if cmd.gitdir == None:
             cmd.gitdir = os.path.abspath(".git")
             if not isValidGitDir(cmd.gitdir):
+                # "rev-parse --git-dir" without arguments will try $PWD/.git
                 cmd.gitdir = read_pipe("git rev-parse --git-dir").strip()
                 if os.path.exists(cmd.gitdir):
                     cdup = read_pipe("git rev-parse --show-cdup").strip()
@@ -3737,6 +3759,7 @@ def main():
             else:
                 die("fatal: cannot locate git repository at %s" % cmd.gitdir)
 
+        # so git commands invoked from the P4 workspace will succeed
         os.environ["GIT_DIR"] = cmd.gitdir
 
     if not cmd.run(args):