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-rwxr-xr-xscripts/automation/trex_control_plane/python_lib/lockfile-0.10.2/lockfile/sqlitelockfile.py155
1 files changed, 155 insertions, 0 deletions
diff --git a/scripts/automation/trex_control_plane/python_lib/lockfile-0.10.2/lockfile/sqlitelockfile.py b/scripts/automation/trex_control_plane/python_lib/lockfile-0.10.2/lockfile/sqlitelockfile.py
new file mode 100755
index 00000000..7dee4a85
--- /dev/null
+++ b/scripts/automation/trex_control_plane/python_lib/lockfile-0.10.2/lockfile/sqlitelockfile.py
@@ -0,0 +1,155 @@
+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()