[PATCH v7 5/7] git-p4: check free space during streaming

[larsxschneider@gmail.com]

From: Lars Schneider <larsxschneider@gmail.com>

git-p4 will just halt if there is not enough disk space while
streaming content from P4 to Git. Add a check to ensure at least
4 times (arbitrarily chosen) the size of a streamed file is available.

Signed-off-by: Lars Schneider <larsxschneider@gmail.com>
---
 git-p4.py | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/git-p4.py b/git-p4.py
index fabc900..3931989 100755
--- a/git-p4.py
+++ b/git-p4.py
@@ -104,6 +104,16 @@ def chdir(path, is_client_path=False):
         path = os.getcwd()
     os.environ['PWD'] = path
 
+def calcDiskFree(dirname):
+    """Return free space in bytes on the disk of the given dirname."""
+    if platform.system() == 'Windows':
+        free_bytes = ctypes.c_ulonglong(0)
+        ctypes.windll.kernel32.GetDiskFreeSpaceExW(ctypes.c_wchar_p(dirname), None, None, ctypes.pointer(free_bytes))
+        return free_bytes.value
+    else:
+        st = os.statvfs(dirname)
+        return st.f_bavail * st.f_frsize
+
 def die(msg):
     if verbose:
         raise Exception(msg)
@@ -2045,6 +2055,14 @@ class P4Sync(Command, P4UserMap):
         self.clientSpecDirs = None
         self.tempBranches = []
         self.tempBranchLocation = "git-p4-tmp"
+        self.largeFileSystem = None
+        self.cloneDestination = None
+
+        if gitConfig('git-p4.largeFileSystem'):
+            largeFileSystemConstructor = globals()[gitConfig('git-p4.largeFileSystem')]
+            self.largeFileSystem = largeFileSystemConstructor(
+                lambda git_mode, relPath, contents: self.writeToGitStream(git_mode, relPath, contents)
+            )
 
         if gitConfig("git-p4.syncFromOrigin") == "false":
             self.syncWithOrigin = False
@@ -2273,6 +2291,14 @@ class P4Sync(Command, P4UserMap):
             if marshalled["code"] == "error":
                 if "data" in marshalled:
                     err = marshalled["data"].rstrip()
+
+        if not err and self.cloneDestination and 'fileSize' in self.stream_file:
+            required_bytes = int((4 * int(self.stream_file["fileSize"])) - calcDiskFree(self.cloneDestination))
+            if required_bytes > 0:
+                err = 'Not enough space left on %s! Free at least %i MB.' % (
+                    os.path.abspath(self.cloneDestination), required_bytes/1024/1024
+                )
+
         if err:
             f = None
             if self.stream_have_file_info:
@@ -3244,7 +3270,6 @@ class P4Clone(P4Sync):
             optparse.make_option("--bare", dest="cloneBare",
                                  action="store_true", default=False),
         ]
-        self.cloneDestination = None
         self.needsGit = False
         self.cloneBare = False
 
-- 
2.5.1