FM / lockfile

/usr/lib/python2.6/site-packages/pip-7.1.2-py2.6.egg/pip/_vendor/lockfile/

/usr/lib/python2.6/site-packages/pip-7.1.2-py2.6.egg/pip/_vendor/lockfile

Name	Size	Mode	Actions
linklockfile.py	2649	0644	edit dl rm
linklockfile.pyc	3079	0644	edit dl rm
mkdirlockfile.py	3098	0644	edit dl rm
mkdirlockfile.pyc	3617	0644	edit dl rm
pidlockfile.py	6221	0644	edit dl rm
pidlockfile.pyc	6348	0644	edit dl rm
sqlitelockfile.py	5540	0644	edit dl rm
sqlitelockfile.pyc	4917	0644	edit dl rm
symlinklockfile.py	2613	0644	edit dl rm
symlinklockfile.pyc	3038	0644	edit dl rm
__init__.py	9162	0644	edit dl rm
__init__.pyc	12089	0644	edit dl rm

Edit: /usr/lib/python2.6/site-packages/pip-7.1.2-py2.6.egg/pip/_vendor/lockfile/sqlitelockfile.py (5540B)

from __future__ import absolute_import, division

import time
import os

try:
    unicode
except NameError:
    unicode = str

from . import LockBase, NotLocked, NotMyLock, LockTimeout, AlreadyLocked

class SQLiteLockFile(LockBase):
    "Demonstrate SQL-based locking."

testdb = None

def __init__(self, path, threaded=True, timeout=None):
        """
        >>> lock = SQLiteLockFile('somefile')
        >>> lock = SQLiteLockFile('somefile', threaded=False)
        """
        LockBase.__init__(self, path, threaded, timeout)
        self.lock_file = unicode(self.lock_file)
        self.unique_name = unicode(self.unique_name)

if SQLiteLockFile.testdb is None:
            import tempfile
            _fd, testdb = tempfile.mkstemp()
            os.close(_fd)
            os.unlink(testdb)
            del _fd, tempfile
            SQLiteLockFile.testdb = testdb

import sqlite3
        self.connection = sqlite3.connect(SQLiteLockFile.testdb)
        
        c = self.connection.cursor()
        try:
            c.execute("create table locks"
                      "("
                      "   lock_file varchar(32),"
                      "   unique_name varchar(32)"
                      ")")
        except sqlite3.OperationalError:
            pass
        else:
            self.connection.commit()
            import atexit
            atexit.register(os.unlink, SQLiteLockFile.testdb)

def acquire(self, timeout=None):
        timeout = timeout is not None and timeout or self.timeout
        end_time = time.time()
        if timeout is not None and timeout > 0:
            end_time += timeout

if timeout is None:
            wait = 0.1
        elif timeout <= 0:
            wait = 0
        else:
            wait = timeout / 10

cursor = self.connection.cursor()

while True:
            if not self.is_locked():
                # Not locked.  Try to lock it.
                cursor.execute("insert into locks"
                               "  (lock_file, unique_name)"
                               "  values"
                               "  (?, ?)",
                               (self.lock_file, self.unique_name))
                self.connection.commit()

# Check to see if we are the only lock holder.
                cursor.execute("select * from locks"
                               "  where unique_name = ?",
                               (self.unique_name,))
                rows = cursor.fetchall()
                if len(rows) > 1:
                    # Nope.  Someone else got there.  Remove our lock.
                    cursor.execute("delete from locks"
                                   "  where unique_name = ?",
                                   (self.unique_name,))
                    self.connection.commit()
                else:
                    # Yup.  We're done, so go home.
                    return
            else:
                # Check to see if we are the only lock holder.
                cursor.execute("select * from locks"
                               "  where unique_name = ?",
                               (self.unique_name,))
                rows = cursor.fetchall()
                if len(rows) == 1:
                    # We're the locker, so go home.
                    return
                    
            # Maybe we should wait a bit longer.
            if timeout is not None and time.time() > end_time:
                if timeout > 0:
                    # No more waiting.
                    raise LockTimeout("Timeout waiting to acquire"
                                      " lock for %s" %
                                      self.path)
                else:
                    # Someone else has the lock and we are impatient..
                    raise AlreadyLocked("%s is already locked" % self.path)

# Well, okay.  We'll give it a bit longer.
            time.sleep(wait)

def release(self):
        if not self.is_locked():
            raise NotLocked("%s is not locked" % self.path)
        if not self.i_am_locking():
            raise NotMyLock("%s is locked, but not by me (by %s)" %
                            (self.unique_name, self._who_is_locking()))
        cursor = self.connection.cursor()
        cursor.execute("delete from locks"
                       "  where unique_name = ?",
                       (self.unique_name,))
        self.connection.commit()

def _who_is_locking(self):
        cursor = self.connection.cursor()
        cursor.execute("select unique_name from locks"
                       "  where lock_file = ?",
                       (self.lock_file,))
        return cursor.fetchone()[0]
        
    def is_locked(self):
        cursor = self.connection.cursor()
        cursor.execute("select * from locks"
                       "  where lock_file = ?",
                       (self.lock_file,))
        rows = cursor.fetchall()
        return not not rows

def i_am_locking(self):
        cursor = self.connection.cursor()
        cursor.execute("select * from locks"
                       "  where lock_file = ?"
                       "    and unique_name = ?",
                       (self.lock_file, self.unique_name))
        return not not cursor.fetchall()

def break_lock(self):
        cursor = self.connection.cursor()
        cursor.execute("delete from locks"
                       "  where lock_file = ?",
                       (self.lock_file,))
        self.connection.commit()

cmd: