Multiple git instances launched by repo compete for SSH key passphrase user input

[GoogleCodeExporter]

Affected Version: VERSION = (1, 21)

STEPS TO REPRODUCE:
1) Use SSH keys protected with a passphrase;
2) repo init --no-repo-verify -u [email protected]:foo/bar.git

repo quite obviously launches more than a single instance of git, and each 
instance attempts to attach to STDIN in order to wait for the user to enter 
passphrase:

-----
Enter passphrase for key '/home/eligovm/.ssh/id_rsa': Enter passphrase for key 
'/home/eligovm/.ssh/id_rsa':
-----

at which point race condition for user input ensues.


EXPECTED ACTION: instances of git DO NOT run in parallel, allowing the user to 
enter key passphrase for each instance separately, without interference from 
the other.

Original issue reported on code.google.com by [email protected] on 6 Aug 2014 at 9:29

[GoogleCodeExporter]

OK, I found that the problem lies in the fact that "['ssh', '-M', '-N', '-o', 
'ControlPath" is not given the opportuinty to obtain the passphrase.

I changed the code in git_config.py around line 457::

    try:
      Trace(': %s', ' '.join(command))
      print(command)
      p = subprocess.Popen(command)
      time.sleep(10) <<<<<<<<<<<<<<<<<<<<<< added this

Then I have enough time to enter the passphrase, and after that everything 
works automatically.

Original comment by [email protected] on 6 Aug 2014 at 9:49