[Python-checkins] python/dist/src/Lib copy_reg.py,1.10,1.11 pickle.py,1.120,1.121
gvanrossum@users.sourceforge.net
gvanrossum@users.sourceforge.net
Tue, 28 Jan 2003 22:14:14 -0800
Update of /cvsroot/python/python/dist/src/Lib
In directory sc8-pr-cvs1:/tmp/cvs-serv24309a
Modified Files:
copy_reg.py pickle.py
Log Message:
Support for extension codes. (By accident I checked in the tests first.)
Index: copy_reg.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/copy_reg.py,v
retrieving revision 1.10
retrieving revision 1.11
diff -C2 -d -r1.10 -r1.11
*** copy_reg.py 27 Dec 2001 16:27:28 -0000 1.10
--- copy_reg.py 29 Jan 2003 06:14:11 -0000 1.11
***************
*** 71,72 ****
--- 71,131 ----
else:
return _reconstructor, args
+
+ # A registry of extension codes. This is an ad-hoc compression
+ # mechanism. Whenever a global reference to <module>, <name> is about
+ # to be pickled, the (<module>, <name>) tuple is looked up here to see
+ # if it is a registered extension code for it. Extension codes are
+ # universal, so that the meaning of a pickle does not depend on
+ # context. (There are also some codes reserved for local use that
+ # don't have this restriction.) Codes are positive ints; 0 is
+ # reserved.
+
+ extension_registry = {} # key -> code
+ inverted_registry = {} # code -> key
+ extension_cache = {} # code -> object
+
+ def add_extension(module, name, code):
+ """Register an extension code."""
+ code = int(code)
+ if not 1 <= code < 0x7fffffff:
+ raise ValueError, "code out of range"
+ key = (module, name)
+ if (extension_registry.get(key) == code and
+ inverted_registry.get(code) == key):
+ return # Redundant registrations are benign
+ if key in extension_registry:
+ raise ValueError("key %s is already registered with code %s" %
+ (key, extension_registry[key]))
+ if code in inverted_registry:
+ raise ValueError("code %s is already in use for key %s" %
+ (code, inverted_registry[code]))
+ extension_registry[key] = code
+ inverted_registry[code] = key
+
+ def remove_extension(module, name, code):
+ """Unregister an extension code. For testing only."""
+ key = (module, name)
+ if (extension_registry.get(key) != code or
+ inverted_registry.get(code) != key):
+ raise ValueError("key %s is not registered with code %s" %
+ (key, code))
+ del extension_registry[key]
+ del inverted_registry[code]
+ if code in extension_cache:
+ del extension_cache[code]
+
+ def clear_extension_cache():
+ extension_cache.clear()
+
+ # Standard extension code assignments
+
+ # Reserved ranges
+
+ # First Last Count Purpose
+ # 1 127 127 Reserved for Python standard library
+ # 128 191 64 Reserved for Zope 3
+ # 192 239 48 Reserved for 3rd parties
+ # 240 255 16 Reserved for private use (will never be assigned)
+ # 256 Inf Inf Reserved for future assignment
+
+ # Extension codes are assigned by the Python Software Foundation.
Index: pickle.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/pickle.py,v
retrieving revision 1.120
retrieving revision 1.121
diff -C2 -d -r1.120 -r1.121
*** pickle.py 29 Jan 2003 00:56:17 -0000 1.120
--- pickle.py 29 Jan 2003 06:14:11 -0000 1.121
***************
*** 29,32 ****
--- 29,33 ----
from types import *
from copy_reg import dispatch_table, _reconstructor
+ from copy_reg import extension_registry, inverted_registry, extension_cache
import marshal
import sys
***************
*** 396,409 ****
if isinstance(obj, list):
! write(MARK)
! for x in obj:
! save(x)
! write(APPENDS)
elif isinstance(obj, dict):
! write(MARK)
! for k, v in obj.iteritems():
save(k)
save(v)
! write(SETITEMS)
getstate = getattr(obj, "__getstate__", None)
--- 397,422 ----
if isinstance(obj, list):
! n = len(obj)
! if n > 1:
! write(MARK)
! for x in obj:
! save(x)
! write(APPENDS)
! elif n == 1:
! save(obj[0])
! write(APPEND)
elif isinstance(obj, dict):
! n = len(obj)
! if n > 1:
! write(MARK)
! for k, v in obj.iteritems():
! save(k)
! save(v)
! write(SETITEMS)
! elif n == 1:
! k, v = obj.items()[0]
save(k)
save(v)
! write(SETITEM)
getstate = getattr(obj, "__getstate__", None)
***************
*** 421,424 ****
--- 434,439 ----
if not getstate:
state = getattr(obj, "__dict__", None)
+ if not state:
+ state = None
# If there are slots, the state becomes a tuple of two
# items: the first item the regular __dict__ or None, and
***************
*** 704,708 ****
dispatch[InstanceType] = save_inst
! def save_global(self, obj, name = None):
write = self.write
memo = self.memo
--- 719,723 ----
dispatch[InstanceType] = save_inst
! def save_global(self, obj, name=None, pack=struct.pack):
write = self.write
memo = self.memo
***************
*** 730,733 ****
--- 745,760 ----
(obj, module, name))
+ if self.proto >= 2:
+ code = extension_registry.get((module, name))
+ if code:
+ assert code > 0
+ if code <= 0xff:
+ write(EXT1 + chr(code))
+ elif code <= 0xffff:
+ write(EXT2 + chr(code&0xff) + chr(code>>8))
+ else:
+ write(EXT4 + pack("<i", code))
+ return
+
write(GLOBAL + module + '\n' + name + '\n')
self.memoize(obj)
***************
*** 1081,1084 ****
--- 1108,1139 ----
self.append(klass)
dispatch[GLOBAL] = load_global
+
+ def load_ext1(self):
+ code = ord(self.read(1))
+ self.get_extension(code)
+ dispatch[EXT1] = load_ext1
+
+ def load_ext2(self):
+ code = mloads('i' + self.read(2) + '\000\000')
+ self.get_extension(code)
+ dispatch[EXT2] = load_ext2
+
+ def load_ext4(self):
+ code = mloads('i' + self.read(4))
+ self.get_extension(code)
+ dispatch[EXT4] = load_ext4
+
+ def get_extension(self, code):
+ nil = []
+ obj = extension_cache.get(code, nil)
+ if obj is not nil:
+ self.append(obj)
+ return
+ key = inverted_registry.get(code)
+ if not key:
+ raise ValueError("unregistered extension code %d" % code)
+ obj = self.find_class(*key)
+ extension_cache[code] = obj
+ self.append(obj)
def find_class(self, module, name):